Intact Group Research Articles

Impact of pesticide use on farmers health condition: case control design

With global populations growing, it is becoming increasingly impossible to ignore food and energy demands. Livestock and agricultural activities produce a large quantity of food. Though the use of agrochemicals has increased agricultural output, they have also been linked to a number of harmful clear adverse effects on human. chemical Pesticides poisonous compounds that negative effect on consumers. the study conducted a case-control was carried out to investigate variations among intact groups on an independent variable of interest. A random sampling approach was employed for 201 farmers. 098Farmers in the research group were exposed to pesticides, whereas farmers in the control group did not apply pesticides. The data were gathered using a survey (PHQ-15)-based on interviews conducted by the investigator. The current study was carried out in five districts (Al-Mashkhab, Al-Abbasiya, Al-hrea, Al-hera, and Al-qadisya). According to the study findings, total farmers' reactions to general physical condition among study group participants are substantially influenced, however, participant of control group show not effected. The negative health effect for farmers spray and exposed to pesticides shows nausea or vomiting, blurred vision, headache, bronchial sensitivity, skin irritation, and shortness of breath eye irritation. the current survey show the Insecticides are the most often used chemicals. The research indicated that pesticide use and exposure have an influence on human health and have a wide range of adverse health effects. According to the findings of the current study, it is critical to use personal protection equipment (PPE) while spraying. Also, undertake a comprehensive exam on farmers on a regular basis.

IMMUNOMODULATING ACTIVITY OF INDIVIDUAL SUBSTANСES ISOLATED FROM THE AERIAL PART OF RHAPONTICUM UNIFLORUM (L.) DC IN EXPERIMENTAL IMMUNODEFICIENCY

Introduction. The development and introduction of new drugs with immunomodulatory effects is one of the priorities of modern medicine. Numerous studies have proven the immunotropic activity of individual substances isolated from medicinal plants (flavonoids, phenylpropanoids, polysaccharides, ecdysteroids, terpenoids, etc.). In this study, it is of interest to determine the immunomodulatory effect of individual substances isolated from Rhaponticum uniflorum (L.) DC. The purpose of the study. Determine the immunomodulatory properties of 20-hydroxyecdysone, 5-О-caffeoylquinic acid and arabino-3,6-galactan, isolated from the aerial part of Rhaponticum uniflorum (L.) DC, in relation to the cellular and humoral components of the immune response during exper-imental immunosuppression caused by cyclophosphamide. Material and methods. The experiments were performed on 100 male mice of the F1 line (CBAxC57Bl/6) weighing 18-20 g. Immunodeficiency was simulated by in traperitoneal administration of cyclophosphamide at a dose of 250 mg/kg once. The experimental group of animals received individual substances intragastricallyin the following doses: 5-О-caffeoylquinic acid - 10 mg/kg, arabino-3,6-galactan - 10 mg/kg, 20-hydroxyecdysone - 3 mg/kg, once a day for 14 days. The intact group of mice received purified water according to the analogous scheme. The state of humoral chain of the im-mune response was estimated according to the quantity of antibody-forming cells (AFC) determined with the use of Cunningham's plaque assay (1965). The state of the cellular chain of the immune response was estimated according to the delayed hypersensitivity reaction. Study results. It has been established that 20-hydroxyecdysone, 5-О-caffeoylquinic acid and arabino-3,6-galactan, isolated from the aerial part of Rhaponticum uniflorum (L.) DC, have immunomodulatory effect on the cellular and humoral components of the immune response in immunosuppres-sion caused by cyclophosphamide. Conclusions. The obtained results argues the feasibility of further research of individual substances, isolated from the aerial part of Rhaponticum uni-florum (L.) DC, with a view to creating new effective immunomodulators of plant origin.

Level of digital competencies in students of Information and Communication Technologies (ICT) at an Ecuadorian university

The present research consists of an exploratory study on student digital competencies. The objective is to analyze the level in its five areas: information, communication, content creation, security and problem solving, in students of the subject 'Computer Projects' of the ninth cycle of the systems engineering career of the Technical University "Luis Vargas Torres" of Esmeraldas. The research had a quantitative approach, with a non-experimental design and two intact groups. As an instrument, a test called "Ikanos", for testing digital competencies of universal character and validated in university students in Europe and Latin America. The results showed that the two groups are not equivalent and have an Intermediate level. This indicated that, despite being students of the ICT career, they could not be placed mostly in Advanced and Expert level. It is concluded about the need to include the development of digital competence as a fundamental element throughout the academic curriculum, from the beginning of the career of Information and Communication Technologies of UTLVTE, implementing strategies, from the first academic cycle, in the career.

Changes in the Cellular Composition of the Rat Thymus 90 Days After Urethane Injection Against the Background of Selenium Intake

The aim of the study is to assess the cellular composition of rat thymus when isolated administration of selenium, urethane and combined exposure to two factors. Material and methods. The study was performed on 34 male Wistar rats, which were divided into 4 groups: 1 – intact, 2 – rats, which received selenium only for 1 month, 3 – animals, which were injected once intraperitoneal urethane, 4 – rats with combined selenium and urethane action. Histological preparations of the thymus were prepared according to generally accepted methods and further evaluated by the method of review microscopy, morphometry, immunohistochemical reactions, electron microscopy, statistical processing of data. Results. Ninety days after selenium, the rat thymus structure is slightly different from intact animals. The introduction of urethane leads to the development of excitation involution of the thymus, which is characterized by morphological changes, and manifests itself in a change in the shape of the organ lobes, in the expansion of the intercole gaps and in the fat tissue thereof, hyperplasia of the cortical substance of the thymus by increasing the number of mature lymphocytes, epithelial cells positive to pancytokeratin. At the ultramicroscopic level, the thymus lymphocyte decreases its nuclear-cytoplasmic index, and increases the number of mitochondria that have a light matrix with a small amount of crystal. Apoptotic bodies and a large number of electron-transparent vacuoles are visualized. When combined, the thymus structure differs from the intact group by an enlarged brain substance, but the number of epithelial cells that are positive to pancytokeratin and Ki67+-cells, as well as cells that express apoptosisregulating protein, decreases. Electron microscopy also indicates a large amount of mitochondria, but with welldefined crystals, when combined with selenium and urethane. There are a small number of electron-transparent vacuoles. Conclusion. The obtained data make it possible to draw a conclusion about the positive influence of the exchange rate of selenium on the T-cell link of immunity, at least for this period of study. In the course of the experiment, it was found that, against the background of the development of the adenoma of the lung caused by the introduction of urethane, at the stage of alveolar epithelium dysplasia signs of excitant thymus involution were detected. When selenium and urethane are combined, less pronounced changes are observed in the examined organ than in the isolated administration of urethane.

Impact of Pronator Quadratus Muscle Tear in Distal Radius Fractures on Patient Outcomes: Analyses of 55 Patients in a Volar Locking Plate Arm of a Randomized Clinical Trial.

Background The advantage of pronator quadratus (PQ) repair following internal fixation via the volar approach in distal radius fracture (DRF) surgery remains unconfirmed in the literature. The aim of this study was to compare grip strength, patient-reported outcomes, and functional results between patients with an intact PQ and those with a ruptured PQ before undergoing surgery with a volar locking plate for dorsally displaced unstable extra-articular DRFs. Methods A total of 120 patients aged 55 years and older were included in a randomized controlled trial comparing a volar locking plate with a dorsal nail plate. Of the 60 patients randomized to the volar plate group, the integrity of the PQ muscle was recorded during surgery for 55 patients, who were included in this study. The outcomes measured were the Quick Disabilities of the Arm, Shoulder, and Hand Outcome Measure (QuickDASH) score, the Patient-Rated Wrist Evaluation (PRWE) score, the EQ-5D index, the visual analog scale (VAS) score, grip strength, and range of motion (ROM). Results The median age was 67 years (range 55 to 88), and the one-year follow-up rate was 98%. Patients with an identified intact PQ (28/55) before surgical release had better QuickDASH scores after one year (2.5 vs 8.0, mean difference 5.5, 95% CI: 1.3 to 9.8, p=0.028). Patients in the intact group also had better EQ-5D Index scores after one year (0.94 vs 0.85, mean difference 0.089, 95% CI: 0.004 to 0.174, p=0.031), and demonstrated better grip strength throughout the trial; after one year: 24 kg vs 20 kg (mean difference 3.9; 95% CI: 0.3 to 7.6, p=0.016). After one year, the intact group had regained 96% of their grip strength and the nonintact group had regained 93% of their grip strength compared to the uninjured side. The observed differences may be of questionable clinical importance, as they were lower than those of previously proposed minimal clinically important differences (MCIDs). Conclusions Patients with a DRF and a ruptured PQ prior to surgery exhibited higher QuickDASH scores and lower EQ-5D index scores after one year. The integrity of the PQ should be reported in future studies.

M2 macrophage-derived soluble factors enhance neuronal density in the frontal cortex of depression-like mice

IntroductionChronic inflammation in depression is associated with decreased levels of neurotrpohic factors and suppressed neurogenesis. We have previously shown that intranasal therapy with soluble factors from M2 macrophages polarized by interaction with apoptotic cells in serum deprivation conditions (M2(LS); LS - low serum) and characterized by anti-inflammatory and pro-regenerative activity leads to the correction of the behavioral pattern in mice with a depression-like state.ObjectivesThe present study focuses on the effect of M2(LS) macrophages on neuronal density in the frontal cortex and hippocampus of depression-like mice.MethodsDepressive-like state was formed in passive male mice (CBAxC57Bl/6)F1) as a result of repeated experience of defeat in agonistic interactions with aggressive partner during 20 days (the sensory contact model). Depression-like mice were then treated intranasally with M2(LS) macrophages conditioned medium for 7 days. After that, the number of mature neurons in the frontal cortex and hippocampus was assessed using Nissl staining.ResultsThe neuronal density in the pyramidal layer of the frontal cortex was significantly lower in depression-like mice than that in the intact control group of mice (p=0,047). At the same time, the number of neurons in the experimental group of mice that received soluble M2(LS) factors, was higher than that in depressive-like untreated control mice (p=0,003) and was comparable to that in the intact group of mice. At the same time the neuronal density in the CA1 and CA3 hippocampal areas did not change in depression-like mice following intranasal treatment with conditioned medium of M2(LS) macrophages.ConclusionsThe data obtained may indicate the neuroprotective effect of M2(LS) macrophages in the stress-induced depression model, which is realized through soluble factors and manifests itself in an increase of the pyramidal neurons density in the frontal cortex.Disclosure of InterestNone Declared

Peritoneal remodeling and changes in its lymphoid component in experimental modeling of adhesion disease in rats

Age changes, inflammatory processes, surgical interventions and heterogeneous pathological effects on the physiological processes of the peritoneum lead to certain changes in the structure of the components of the peritoneum, which leads to remodeling of the tissue structures of the abdominal cavity. According to the literature, the most frequent consequence of such remodeling of tissue structures of the peritoneum is the development of an adhesion process. To date, there are no data on the study of the lymphoid component of mesentery tissues, which is the goal of further research. The purpose of the work: to study the process of remodeling of peritoneal tissue during experimental adhesion formation and the specificity of changes in its lymphoid component in rats compared to the norm. Research materials and methods: preparation, macroscopic, microscopic, histological (production of film preparations), staining of preparations with hematoxylin and eosin, mathematical (morphometric grids - counting the number of immunocompetent cells per 1000 μm2 standard area), statistical processing according to Student. Results: experimental adhesion disease is characterized by a gradual process of remodeling of the mesenteric tissues of the small intestine and, as a result, the formation of connective tissue neoplasms. The mesentery of the small intestine loses its elasticity and mobility and thickens considerably. The process of experimental adhesion formation was accompanied by dynamic changes in the number of lymphocytes. Conclusions: these structures are thin and homogeneous on the 7th day; hard, dense and granular on the 14th day; contain solid conglomerates of heterogeneous structures on the 21st day after talc injection. The number of lymphocytes in this structure gradually increases: on day 7 - by 2 % in animals of group II, on day 14 - by 30 % in animals of group III, and on day 21 - by 36 % in animals of group IV, compared to animals of the intact group

ГЕПАТОПРОТЕКТОРНАЯ АКТИВНОСТЬ ПРОИЗВОДНОГО 2-АМИНОЭТАНСУЛЬФОНОВОЙ КИСЛОТЫ ПРИ ЛЕКАРСТВЕННОМ ПОРАЖЕНИИ ПЕЧЕНИ В ЭКСПЕРИМЕНТЕ

We studied the hepatoprotective activity of 2-aminoethanesulfonic acid derivative (laboratory code LBK-527) in antibiotic-associated liver injury. The studies were performed on 18 laboratory rats (Wistar line), divided into four groups: 1st - intact animals, 2nd - control group with tetracycline drug-induced liver injury (TDLI), 2nd group - experimental with DILI and injected LBK- 527 (28 mg/kg), group 3 – experimental with DILI, injected N-adenosyl-S-methionine for 14 days. DILI was induced by intragastric administration of tetracycline at a dose of 500 mg/kg for 5 days. Animals were removed from the experiment on 7 and 14 days and studied activity of aspartic (AST) and alanine (ALT) aminotransferases, total protein (TP), total bilirubin (TB), alkaline phosphatase (ALP), and creatinine (C). The liver was taken from all animals, weighed, and the macro- and microstructure was assessed, stained with hemotoxylin and eosin according to the standard method using a Nikon Eclipes Ni light microscope (Japan). Antibiotic-associated liver injury occurs of the cholestatic type and is characterized by an increase in ALP, TB and the ALT/ALP ratio by two times, decomposition of the hepatic beams, moderate necrosis, fatty degeneration of hepatocytes by 7 days. The administration of LBK-527 and N-adenosyl-S-methionine reduced the toxic effect of tetracycline on the liver, which was manifested in a decrease in the activity of cytolytic icholestatic syndromes, preservation of the beam structure of the liver, degeneration and congestion in the hepatic veins. By day 14, in the control group of animals there was a decrease in the activity of intracellular enzymatic systems of hepatocytes, but complete restoration of the liver structure did not occur in comparison with the intact group. Compound LBK-527 by day 14 The area of the cytoplasm, nucleus and nuclear-cytoplasmic ratio approached the values of the intact group. The appearance of multinucleated hepatocytes indicated the activation of the synthetic activity of the liver and the launch of regeneration mechanisms. Thus, we can conclude that the pharmaceutical composition under study has a hepatoprotective effect.

LOCOMOTOR ACTIVITY OF RATS WITH BLAST-INDUCED TRAUMATIC BRAIN INJURY IN A COMPLEX MAZE

Aim – to investigate the peculiarities of rats with blast-induced brain injury movement in the complex maze.Material and methods. The study was carried out on 15 sexually mature Wistar rats. All animals were randomly divided into 3 groups: experimental group (n=5), which was anesthetized and exposed to an air shock wave with an overpressure of 26-36 kPa; sham group (n=5), which was only anesthetized, and intact group (n=5). The study of locomotor activity was performed using a complex maze for 5 consecutive days, starting on the 1st day after the simulation of blast-induced brain injury. The route of rat`s movement through the maze of three groups was graphically depicted and visually analyzed.Results of the study. The complex maze is considered to be complicated due to the presence of a central zone and T-shaped branches to the right and left, ending with feeders. The complication of the situation and task lead to fear with rapid adaptation of healthy rats. However, if the brain functions are impaired, the experimental animal loses its physiological ability to adapt and shows signs of anxiety. The analysis of the images of the movement paths showed that on the 1st day of training, the rats of the experimental group moved more actively, despite the fact that the animals did not yet know that food was waiting for them. They performed monotonous movements and went to the side sectors more often. On 2nd day, the experimental rats were more active and explored the maze more stereotypically than intact animals. On 3rd and 4th days, clear signs of spatial memory impairment in the experimental group were found in terms of lengthening the path to the feeder. On the 5th day, it was found that the experimental rats were still poorly oriented in the maze, with a monotonous examination of the side sectors.Conclusions. Thus, mild blast-induced traumatic brain injury leads to persistent impairment of spatial memory, as well as behavioral disorders in the form of anxiety. The rats of the experimental group demonstrated stereotypical locomotor activity, as evidenced by the examination of the lateral sectors of the complex maze. At the same time, the memory for food reinforcement was well developed and retained.

DYNAMIC PORTRAIT OF ALVEOLAR MACROPHAGES IN EXPERIMENTAL DIABETES MELLITUS

SUMMARY. Diabetes mellitus (DM) is a globally prevalent metabolic disorder with profound implications for systemic organs, yet its intricate relationship with the respiratory system, particularly the alveolar macrophages (AM), remains underexplored. The aim – to comprehensively investigate the pathological alterations in AM during the progression of experimental diabetes mellitus. Material and Methods. An experimental investigation was conducted involving 88 male Wistar rats, categorized into intact (Group 1), control (Group 2), and experimental (Group 3) groups. Experimental diabetes was induced using streptozotocin (Sigma, USA), diluted in 0.1 M citrate buffer with a pH of 4.5, at a dose of 60 mg/kg of body weight. Tissue samples were collected at intervals of 14, 28, 42, and 70 days. Electron microscopy analysis was employed to examine lung tissue fragments. Results. On the 14th day, increased functional activity of AMs was observed, marked by distinct nuclear contours and shallow nucleolemic intussusceptions. Subsequent days revealed alterations in mitochondrial morphology, Golgi apparatus, and endoplasmic reticulum, culminating in dystrophic changes by the 70th day. The study period exhibited a dynamic temporal progression, showcasing the multifaceted responses of AMs to diabetic conditions. These responses include heightened functional activity, structural modifications in organelles, and a subsequent shift towards dystrophic changes, providing a comprehensive view of the evolving dynamics of AMs during the course of experimental diabetes mellitus. Conclusions. The study reveals a dynamic temporal progression in alveolar macrophages during the course of experimental diabetes mellitus. Early heightened functional activity transitions into dystrophic changes, providing insights into the evolving functional deficiency of macrophages as diabetes advances, contributing to the understanding of diabetes-related respiratory pathology.

DISTRIBUTION AND CHARACTERISTICS OF MESENTERIC MILK SPOTS IN HEALTHY RATS AND THOSE WITH ADHESION DISEASE

Introduction. The adhesion process occurs in more than 80% of cases after all abdominal operations. The process of adhesion formation and, as a consequence, chronic inflammation involve the lymphoid elements (Peyer's spots, solitary follicles) present in the peritoneum and submucosa of the intestine, causing a pathological immune response. Fat-associated lymphoid clusters (FALCs), known as mammary structures, are also found in other fat reservoirs, such as the pericardium, mediastinum, and pleural cavity. The problem of visualizing milk spots in various structures of the peritoneum remains open. Relevance. Despite the fact that as early as 1921, scientists emphasized the presence of milk spots in the abdominal cavity and their great biological significance, the results of experimental studies related to milk spots are still relatively few. The novelty consists in investigating the peculiarities of the distribution of milk spots in the mesentery of the intestine with adhesion disease in rats in comparison with the health animals.
 Objective of this study is to detect milk spots, to investigate their topography and structure in the mesentery of the intestine in the health and in adhesion disease.
 Materials and methods: The experiment involved tissue preparation, macroscopic examination, histological analysis of hematoxylin and eosin-stained film preparations.
 Results. Milk spots of the intestinal mesentery in rats from the intact group are represented by round formations, 1-2 μm in diameter, white in color, uniformly and diffusely located on the area of the mesentery of the small and large intestine. Microscopically, they are characterized as a cluster of lymphocytes, plasma cells, and macrophages belonging to FALC lymphoid tissue. The area of milk spots of the peritoneum in the experimental groups varies depending on the course of the process of adhesion formation. Individual small white and gray granulations were observed in the animals of the II experimental group on the 7th day. On the 14th day of observation in the III group, the diameter of the milk spots reached 2-2.5 mm, they appeared as white granular clusters. On the 21st day, the animals of the IV group demonstrated an abundant accumulation of elliptical whitish structures, 3-4 mm in diameter near the blood vessels that differed significantly from the indicators of the other groups.
 Conclusion. The study has expanded knowledge regarding the distribution and composition of milk spots in the normal mesentery compared to those observed in adhesion disease. According to data obtained, milk spots are lymphoid tissue, represented by various types of lymphocytes, macrophages and plasma cells. The question of whether the lymphocytes found in the milk spots belong to different subpopulations, the dynamics of their number during the main stages of adhesion formation, remains an open question requiring further scientific research.

EXPLORATORY ACTIVITY OF RATS IN THE ACUTE PERIOD OF MILD BLAST-INDUCED TRAUMATIC BRAIN INJURY

The relevance of this work is related to the widespread use of explosive devices in military conflicts. More common and "invisible" is mild blast-induced brain injury. This can manifest through anxiety, emotional dysregulation, and spatial memory impairments. However, significant variability exists in modeling blast-induced traumatic brain injury and spatial memory assessment methods. This study aimed to investigate the exploratory activity of rats during the acute phase of mild blast-induced traumatic brain injury modelled by using a newly developed device.
 The study carried out on 18 sexually mature male Wistar rats weighing 220-270 g. The selected rats were divided into three groups: an experimental group (n=6), animals were modeled with blast-induced trauma by generating an air shock wave with an overpressure of 26.4±3.6 kPa, sham group (n=6), animals were subjected only to inhalation anesthesia with halothane and fixed in a horizontal position, and an intact group (n=6). The exploratory activity was recorded by the iPhoneXR camera; the route of movement through the maze of rats from three groups was graphically depicted and visually analyzed, as well as the number of entries into the "false shelters" was counted and the performance of experimental, sham and intact rats was compared. On the 1st day of the post-traumatic period, the experimental rats explored a greater number of "false shelters", by 72% (p<0.01) compared to intact animals and by 65% (p<0.05) compared to control animals. On the 3rd day, this activity was higher by 53% (p<0.05) compared to intact and by 67% (p<0.05) compared to control rats. On day 7, experimental rats explored more, by 86% (p<0.01) compared to intact rats and also by 86% (p<0.01) compared to control animals. The obtained results indicate an increase in the exploratory activity of rats in the acute period of mild blast-induced brain injury.

Criteria-based assessment of analgesic activity of condensed 3-aminothieno[2,3-b]pyridines and 1,4-dihydropyridines derivatives based on dataexperimental studies

BACKGROUND: An urgent task in pharmacology is to identify highly effective drugs with analgesic and anti-inflammatory activity. Heterocyclic cyanothioacetamide compounds are of considerable interest. Most authors evaluate the results of studies with separate private indicators of analgesic activity, and their comprehensive criterion assessment is insufficiently defined.
 AIM: Development of a criterion assessment in the study of analgesic activity and the establishment of its generalized criteria for samples of chemical compounds of medicinal products.
 MATERIALS AND METHODS: The experiments were performed on 390 male rats weighing 250–280 g in the laboratory of the Department of Fundamental and Clinical Pharmacology of St. Luke Lugansk State Medical University. Intact, control and reference (comparison group) groups of ten animals in each group were formed for each pharmacological test. In the intact group, the rats were unharmed. The control group received 2 mL of 0.9% sodium chloride solution intragastrically before each pharmacological test to establish analgesic activity. The reference group was injected with sodium metamizole at a dose of 7 mg/kg intragastrally once 1.5 h before modelling an acute pain reaction. Ten experimental groups were also formed, in which rats were injected with appropriate samples of new original studied derivatives of condensed 3-aminothieno[2,3-b]pyridines and 1,4-dihydropyridine intragastrically at a dose of 5 mg/kg 1.5 h before modelling acute pain syndrome. Tests for orofacial trigeminal pain, thermal immersion and hot plate were simulated. The indicators of the analgesic effect were the frequency of scratching movements in the orofacial trigeminal pain test and a statistically significant increase in the latent reaction period after the administration of the studied substances in the thermal immersion tests of the tail and hot plate.
 RESULTS: The studied samples with ciphers AZ-023, AZ-331 and AZ-383 showed maximum analgesic activity. The proposed criterion of analgesic activity in the experimental groups receiving thienopyridine derivatives with the AZ-023 cipher, according to the results of three tests, was 50.1, exceeding the indicator in the comparison group by 42 times. The values of this criterion in the experimental groups that received new 1,4-dihydropyridine derivatives with laboratory ciphers AZ-331 and AZ-383 for preventive purposes were the maximum in this series of experiments (64.3 and 68.4), which is 53–57 times higher than that of sodium metamizole.
 CONCLUSION: The methodology for assessing analgesic activity can be improved based on a criteria-based approach with the aggregation of particular indicators into an abstract model that allows quantifying the degree of analgesic activity. An integral criterion for the analgesic activity of cyanothioacetamide derivatives based on experimental data is proposed. In the future, the proposed approach can be used in studies of various analgesic samples.

Comparative investigation on beam-to-beam connection with different types of connecting plates

The spliced glued laminated timber (glulam) beams have extensive applications in large-span timber structures since the length of the long solid wood beams is limited by transportation and construction. This paper investigated the flexural performance of glulam beam-to-beam connections with connecting plates and self-trapping screws. The influence of connecting plate types (steel plate, bamboo scrimber, and plybamboo plate) on the flexural performance of the spliced beams was studied. A total of 12 beams were designed, including the intact beam group (3 specimens) and the spliced beam group (9 specimens). The failure modes, ultimate bearing capacity, stiffness, moment-rotation curves, and carbon emissions of spliced beams with different connecting plates were studied. The test results showed that the failure mode of the spliced beams mainly included bending failure of glulam and fracture of the connecting plates. The average bearing capacity of the spliced beams with bamboo scrimber plates and those with steel plates could reach the intact beams. The average stiffness of the spliced beams with bamboo scrimber plates was higher than that of the splice beams with steel plates, reaching 97.6% of the intact beams. The average bearing capacity and stiffness of the splice beams with plybamboo plate reached 80.9% and 92.7% of the intact beams, respectively. A theoretical model of the spliced beams with bamboo scrimber plates was proposed and verified by tests data. Comparisons of the analytical and the test results reveal that the model can predict the moment capacity of the spliced beams with bamboo scrimber plates corresponding specific failure mode in this test.

Stress Changes in the Canine Radius after Locking Plate Fixation Using Finite Element Analysis.

The aim of this study was to evaluate the stress changes in the radii beneath the locking plates (LP) of dogs implanted with LP using finite element analysis (FEA). The study included radii harvested from eight dogs. After computed tomography (CT) scans of the forelimb, the articular surface of the radius was fixed using resin. Material tests were conducted to identify the yield and fracture points and for verification with FEA. The CT data of the radius were imported into FEA software. The radii were classified into three groups based on the placement of the LP (nonplate placement, intact group; 1 mm above the radial surface, LP + 1 mm group; 3 mm above the radial surface, LP + 3 mm group). Equivalent, maximum, and minimum principal stresses and minimum principal strain were measured after FEA at the radial diaphysis beneath the plate. In shell elements, the LP + 1 mm and LP + 3 mm groups showed a significantly lower maximum principal stress compared with the intact group. In solid elements, the LP + 1 mm and LP + 3 mm groups showed a significantly higher equivalent stress and a significantly lower maximum principal stress compared with the intact group. When an axial load is applied to the radius, LP placement reduces the tension stress on the cortical bone of the radius beneath the plate, possibly related to implant-induced osteoporosis and bone formation in the cortical bone beneath the plate.

Fascia Lata Autografts Achieve Interface Healing With the Supraspinatus Muscle Histologically and Mechanically in a Rat Supraspinatus Tendon Reconstruction Model for Massive Irreparable Rotator Cuff Tears

PurposeTo evaluate the histologic healing process and mechanical characteristics of the interface between a fascia lata autograft and supraspinatus muscle by establishing a supraspinatus tendon reconstruction model for chronic massive, irreparable rotator cuff tears (MIRCTs). MethodsA total of 40 rats were studied. Eight rats were sacrificed to establish an intact control group, and the other rats were first established as the chronic MIRCTs model and then developed as the supraspinatus tendon reconstruction model. Histology, fatty infiltration, mechanics and the open field test for the interface between the fascia lata autograft and muscle were assessed at 2, 4, 8 and 16 weeks postoperatively. ResultsHistologically, the interface between the fascia lata autograft and muscle gradually regenerated structural similarities to the normal muscle-tendon interface by 16 weeks postoperatively. The amounts of collagen I and III were both increased significantly during the healing time and stabilized at 8 weeks postoperatively. Fatty infiltration was obvious in the supraspinatus muscle 4 weeks after the MIRCTs model. However, the degree of fatty infiltration in the supraspinatus muscle gradually decreased after supraspinatus tendon reconstruction and stabilized at 8 weeks postoperatively. The ultimate failure force and the ultimate stress gradually increased from 2 to 16 weeks and reached the level of the intact control tendon at 16 weeks postoperatively (P=0.086). The movability of the forepaw returned to normal in the open field test (P=0.907). ConclusionsIn this rat supraspinatus tendon reconstruction model, fascia lata autografts showed good interface healing with the supraspinatus muscle, and fatty infiltration in the supraspinatus muscle was histologically decreased. The interface between the fascia lata autograft and muscle can sustain mechanical strength similar to the anatomical muscle–tendon interface. Clinical RelevanceThe supraspinatus tendon reconstruction technique using fascia lata autografts might be a good histological and biomechanical option for treating MIRCTs.

Hippocampal resting-state connectivity is associated with posterior-cortical cognitive impairment in Parkinson's disease.

Frontal and posterior-cortical cognitive subtypes in Parkinson's disease (PD) present with executive/attention and memory/visuospatial deficits, respectively. As the posterior-cortical subtype is predicted to progress rapidly toward dementia, the present study aimed to explore biological markers of this group using resting-state functional magnetic resonance imaging (rs-fMRI). K-means cluster analysis delineated subtypes (cognitively intact, frontal, posterior-cortical, and globally impaired) among 85 people with PD. A subset of PD participants (N=42) and 20 healthy controls (HCs) underwent rs-fMRI. Connectivity of bilateral hippocampi with regions of interest was compared between posterior-cortical, cognitively intact, and HC participants using seed-based analysis, controlling for age. Exploratory correlations were performed between areas of interest from the group analysis and a series of cognitive tests. The posterior-cortical subtype (N=19) showed weaker connectivity between the left hippocampus and right anterior temporal fusiform cortex compared to the cognitively intact (N=11) group, p-false discovery rate (FDR)=.01, and weaker connectivity between bilateral hippocampi and most fusiform regions compared to HCs (N=20). No differences were found between HCs and cognitively intact PD. Exploratory analyses revealed strongest associations between connectivity of the right anterior temporal fusiform cortex and left hippocampus with category fluency (p-FDR=.01). Results suggest that weakened connectivity between the hippocampus and fusiform region is a unique characteristic of posterior-cortical cognitive deficits in PD. Further exploration of hippocampal and fusiform functional integrity as a marker of cognitive decline in PD is warranted.

Influence of inner ear impedance on middle ear sound transfer functions

IntroductionFor experimental studies on sound transfer in the middle ear, it may be advantageous to perform the measurements without the inner ear. In this case, it is important to know the influence of inner ear impedance on the middle ear transfer function (METF). Previous studies provide contradictory results in this regard. With the current study, we investigate the influence of inner ear impedance in more detail and find possible reasons for deviations in the previous studies. Methods11 fresh frozen temporal bones were prepared in our study. The factors related to inner ear impedance, including round window membrane stiffness, cochleostomy, cochlea fluid and cochlea destruction were involved in the experimental design. After measuring in the intact specimen as a reference (step 1), the round window membrane was punctured (step 2), then completely removed (step 3). The cochleostomy was performed (step 4) before the cochlear fluid was carefully suctioned through scala tympani (step 5) and scala vestibuli (step 6). Finally, cochlea was destroyed by drilling (step 7). Translational and rotational movement of the stapes footplate were measured and calculated at each step. The results of the steps were compared to quantify the effect of inner ear impedance changing related to the process of cochlear drainage. ResultsAs the inner ear impedance decreases from step 1 to 7, the amplitudes of the METF curves at each frequency gradually increase in general. From step 6 on, the measured METF are significantly different with respect to the intact group at high frequencies above 3 kHz. The differences are frequency dependent. However, the significant decrement of rotational motion appears at the frequencies above 4.5 kHz from the step 5. ConclusionThis study confirms the influence of inner ear impedance on METF only at higher frequencies (≥3 kHz). The rotational motions are more sensitive to the drainage of fluid at the higher frequency. Study results that found no influence of cochlea impedance may be due to incomplete drainage of the cochlea.

Pharmacologic activity of mGLUR4 agonist in a model of primary open-angle glaucoma: A preclinical experimental study

Background. Worldwide, more than 67 million people suffer from glaucoma. In Russia, this number exceeds 1.08 million people. Annually, the number of primary cases increases by 3–4%. The increasing prevalence of glaucoma intensifies the search for neuroprotectants that can reduce the loss of retinal ganglion cells, thereby impeding the progression of the disease. Objective. To study of the pharmacological activity of mGLUR4 agonist, ZC64-0001 substance, on a model of primary open-angle glaucoma. Methods. The conducted preclinical study involved 60 sexually mature male Wistar rats, weighing 180–220 g. The observation period was 73 days. The animals were divided into 6 groups with 10 animals in each. Group 1 included intact animals (without any manipulations); Group 2 included negative control animals with the water injected in the anterior chamber of the eye; in Group 3–6, primary open-angle glaucoma was modelled by injecting 1% hyaluronic acid solution into the anterior chamber of the eye once every 7 days from day 1 to day 62 of the study. Animals in Group 4 were treated intragastrically with H-[(4-chlorophenyl)methyl]-1,6-dihydro-4-methoxy-1-(2-methylphenyl)-6-oxo-3-pyridazinecarboxamide under the laboratory code of ZC64-0001 at a dose of 10 mg/kg. Animals in Group 5 received Mexidol as a comparison drug intramuscularly at a dose of 25.7 mg/kg. Animals in Group 6 were treated with a Timolol instillation at a dose of 0.009 ml/kg. The studied compounds were administered from day 63 of the study once a day for 10 days. The evaluated indicators included the level of microcirculation in the retina, the amplitude of a-wave and b-wave of the electroretinogram, and the number of retinal ganglionic layer nuclei in the setting of the conducted treatment. Statistical processing of the data was performed using the Statistica 10.0 software (StatSoft, USA). Differences were determined at the significance level of p ˂ 0.05. Results. ZC64-0001 increased the level of microcirculation relative to the group with modelled glaucoma by 11.5%, with this indicator being statistically significantly different from that both in the group with modelled glaucoma and the intact group ( р < 0.05). In the group of animals receiving ZC64-0001, the amplitude of a-wave increased relative to the primary glaucoma group by 17.7%, with this index being statistically different from the groups of intact animals and negative control (р < 0.05). The b-wave amplitude increased by 34.4% relative to the group with modelled glaucoma, being statistically different from the intact group, negative control group, pathology modelled group, and comparison drug groups ( р < 0.05). Administration of ZC64-0001 increased the number of retinal ganglion cell nuclei relative to the group with modelled glaucoma by 41.0%, which had a statistically significant difference from all the studied groups ( р < 0.05). Conclusion. The ZC64-0001 compound demonstrated high neuroprotective properties in a model of primary open-angle glaucoma, leading to an improvement in retinal microcirculation, an increase in the wave amplitude according to the conducted electrophysiological study, and an increase in the number of ganglion cell nuclei.

Differences in Clinical Outcomes Between Patients With Retear After Supraspinatus Tendon Repair and Those With Intact Repair at 5-Year Follow-up

Background: It is well known that rotator cuff repair is associated with an overall retear rate of 21% to 26%. However, a cuff retear may not necessarily be associated with poor clinical outcomes. Hypothesis: There would be no difference in clinical outcomes between patients with a cuff retear and those with an intact repair at a midterm follow-up of 5 years. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective study was conducted involving patients who received arthroscopic complete repair of the supraspinatus tendon between January 2009 and December 2017. Patients who did not have a postoperative magnetic resonance imaging (MRI) scan or who had a follow-up of <5 years were excluded. Clinical outcomes, including the visual analog scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, and active forward flexion (FF) of the involved shoulder were assessed at the 2-year and 5-year follow-up points. Results: The study group included 105 patients with a mean follow-up of 85 months. MRI scans were performed at a mean of 20 months. Fourteen full-thickness cuff retears and 91 intact repairs were identified using postoperative MRI scans. Significant improvement in VAS score, ASES score, and FF were found between the preoperative assessment and the 2 designated follow-up points (2 years and 5 years) in both the cuff retear and the intact repair groups (P < .001). The VAS and ASES scores at the 2-year follow-up for the intact repair group were 1.8 ± 2.0 and 80.7 ± 18.1, respectively. The corresponding values for the retear group were 2.3 ± 2.2 and 71.9 ± 19.5, respectively. No significant difference was found between the 2 groups in the VAS and ASES scores at the 2-year follow-up. However, patients with an intact repair had a better VAS score (1.4 ± 1.8; P = .049) and ASES score (81.7 ± 17; P = .019) than those with a cuff retear at the 5-year assessment (3.0 ± 2.8 and 67.1 ± 22.9, respectively). In the intact repair group, 91% of patients achieved the minimal clinically important difference for the 5-year VAS score, compared with 54% in the cuff retear group (P < .001). The corresponding values for the 5-year ASES score were 80% and 54%, respectively (P = .044). FF measurements at the 5-year follow-up in patients with intact repair and those with a cuff retear were 161°± 23° and 144°± 37°, respectively (P = .059). Continuous improvement in VAS score and FF between the 2-year and 5-year follow-up was observed in the intact repair group (P = .005 and P = .04, respectively). Conclusion: The patients with an intact repair had better VAS and ASES scores compared with those who had a cuff retear at a midterm follow-up of 5 years. Between the 2-year and the 5-year follow-up, some further improvement was observed in the VAS score and FF in the intact repair group.