Muscle Bundles Research Articles

A case of mitral regurgitation due to bilateral undifferentiated papillary muscles with detailed preoperative diagnosis of associated morphological abnormalities

Incomplete differentiation of the mitral valve structures during fetal life results in the papillary muscles and tendon cords becoming hypoplastic, a condition termed undifferentiated papillary muscles (UDPM). This fetal abnormality causes a group of diseases that cause mitral valve dysfunction in adult life. Here, we report a case of UDPM centered on the medial posterior apex in which detailed morphological abnormalities were diagnosed preoperatively using echocardiography and three-dimensional computed tomography (3DCT) analysis, contributing to plastic surgery.The patient was a 64-year-old man who was followed up for several years for atrial functional mitral regurgitation (MR), ultimately developing heart failure. His MR was severe, and he was referred for surgery.Echocardiography revealed restrictive tendon cords primarily in the posterior apex, abnormal muscle bundles in the lower part of the valve, and findings indicative of UDPM; this was considered the main cause of MR. The patient had surgery findings similar to the preoperative diagnosis, which greatly aided the surgery. Postoperatively, the MR was well-controlled and mild.UDPM may present as various morphologic and functional abnormalities, including partial club-shaped tendinous MR and rheumatoid mitral stenosis, which are rarely accurately diagnosed preoperatively. Detailed analysis of morphological abnormalities using 3DCT or other methods may be beneficial for a successful plasty.

Rhabdomyomatous Mesenchymal Hamartoma: Report of 4 Cases With Histochemical and Immunohistochemical Findings and Emphasis on Potential Pitfalls.

Rhabdomyomatous mesenchymal hamartoma (RMH) typically presents as a congenital midline head and neck cutaneous polyp in infants. Perianal and mucocutaneous lesions have been reported, and recently, acquired adult-onset variants have been proposed. This makes the true prevalence, etiopathogenesis, and clinicopathologic distribution and classification of RMHs in children compared with those in adults uncertain. We performed a retrospective review to highlight the salient histopathologic, histochemical, and immunohistochemical features in RMHs and to emphasize their specific clinicopathologic criteria to avoid diagnostic pitfalls. We found 4 (0.3%) infants [2 female infants and 2 male infants, average age: 4 months] with mental, nasal, lingual, and perianal midline RMHs (average size: 1.0 cm) of 1303 patients with cutaneous polypoid lesions. Three were isolated, and 1 was associated with Goldenhar syndrome. The cutaneous polyps demonstrated intermixed skeletal muscle, adipose, and fibrocollagenous core stroma that extended into the dermis and around the dermal appendages. The lingual lesion demonstrated skeletal muscle and fibrocollagenous stroma with prominent nerve bundles and little adipose tissue. All showed interstitial loose mesenchyme. Masson trichome demarcated the triphasic stromal components. Alcian blue demonstrated the loose myxoid mesenchyme. Elastic van Gieson did not show elastic fibers. Desmin demonstrated the skeletal muscle bundles, S100 highlighted the adipose tissue lobules and the nerve bundles, and CD34 displayed the mesenchymal stroma. Ki67 showed a low proliferation index in the loose mesenchyme. Smooth muscle actin did not reveal smooth muscle bundles, but with CD31, they highlighted the thick blood vessels. CD117 revealed prominent mast cells. From our retrospective review series, 4 cases that originally diagnosed as RMHs were excluded. Likewise, we found some examples of the reported cases in the English literature that might have been mistaken for RMHs. This is because they did not fulfill the diagnostic clinicopathologic criteria. RMH constitutes a rare entity with specific clinicopathologic features. Most lesions are isolated. Some are associated with congenital anomalies and syndromes. Strict clinicopathologic diagnostic criteria should be applied to avoid mislabeling look-alike lesions for RMHs.

Clinicopathologic and endoscopic characteristics of ten patients with gastric hamartomatous inverted polyp: a single center case series

BackgroundGastric hamartomatous inverted polyps (GHIPs) are not well characterized and remain diagnostically challenging due to rarity. Therefore, this study aims to investigate the clinicopathologic and endoscopic characteristics of patients with GHIP.MethodsWe retrospectively reviewed clinicopathologic and endoscopic features of ten patients with GHIP who were admitted to Beijing Friendship Hospital from March 2013 to July 2022. All patients were treated successfully by endoscopic resection.ResultsGHIPs were usually asymptomatic and found incidentally during gastroscopic examination. They may be sessile or pedunculated, with diffuse or local surface redness or erosion. On endoscopic ultrasonography, the sessile submucosal tumor-type GHIP demonstrated a heterogeneous lesion with cystic areas in the third layer of the gastric wall. Histologically, GHIPs were characterized by a submucosal inverted proliferation of cystically dilated hyperplastic gastric glands accompanied by a branching proliferation of smooth muscle bundles. Inflammatory cells infiltration was observed in the stroma, whereas only one patient was complicated with glandular low-grade dysplasia. Assessment of the surrounding mucosa demonstrated that six patients (60%) had atrophic gastritis or Helicobacter pylori–associated gastritis, and four patients (40%) had non-specific gastritis. Endoscopic resection was safe and effective.ConclusionsGHIPs often arise from the background of abnormal mucosa, such as atrophic or H.pylori-associated gastritis. We make the hypothesis that acquired inflammation might lead to the development of GHIPs. We recommend to make a full assessment of the background mucosa and H. pylori infection status for evaluation of underlying gastric mucosal abnormalities, which may be the preneoplastic condition of the stomach.

The role of the extracellular matrix in the reduction of lateral force transmission in muscle bundles: A finite element analysis

Background and objectiveAging is associated with a reduction in muscle performance, but muscle weakness is characterized by a much greater loss of force loss compared to mass loss. The aim of this work is to assess the contribution of the extracellular matrix (ECM) to the lateral transmission of force in humans and the loss of transmitted force due to age-related modifications. MethodsFinite element models of muscle bundles are developed for young and elderly human subjects, by considering a few fibers connected through an ECM layer. Bundles of young and elderly subjects are assumed to differ in terms of ECM thickness, as observed experimentally. A three-element-based Hill model is adopted to describe the active behavior of muscle fibers, while the ECM is modeled assuming an isotropic hyperelastic neo-Hookean constitutive formulation. Numerical analyses are carried out by mimicking, at the scale of a bundle, two experimental protocols from the literature. ResultsWhen comparing numerical results obtained for bundles of young and elderly subjects, a greater reduction in the total transmitted force is observed in the latter. The loss of transmitted force is 22 % for the elderly subjects, while it is limited to 7.5 % for the young subjects. The result for the elderly subjects is in line with literature studies on animal models, showing a reduction in the range of 20–34 %. This can be explained by an alteration in the mechanism of lateral force transmission due to the lower shear stiffness of the ECM in elderly subjects, related to its higher thickness. ConclusionsComputational modeling allows to evaluate at the bundle level how the age-related increase of the ECM amount between fibers affects the lateral transmission of force. The results suggest that the observed increase in ECM thickness in aging alone can explain the reduction of the total transmitted force, due to the impaired lateral transmission of force of each fiber.

Investigating the role connective tissue fibroblasts play in the altered muscle anatomy associated with the limb abnormality, Radial Dysplasia.

Radial dysplasia (RD) is a congenital upper limb birth defect that presents with changes to the upper limb anatomy, including a shortened or absent radius, bowed ulna, thumb malformations, a radially deviated hand and a range of muscle and tendon malformations, including absent or abnormally shaped muscle bundles. Current treatments to address wrist instability caused by a shortened or absent radius frequently require an initial soft tissue distraction intervention followed by a wrist stabilisation procedure. Following these surgical interventions, however, recurrence of the wrist deviation remains a common, long-term problem following treatment. The impact of the abnormal soft connective tissue (muscle and tendon) anatomy on the clinical presentation of RD and the complications following surgery are not understood. To address this, we have examined the muscle, fascia and the fascial irregular connective tissue (ICT) fibroblasts found within soft connective tissues, from RD patients. We show that ICT fibroblasts isolated from RD patients are functionally abnormal when compared to the same cells isolated from control patients and secrete a relatively disordered extracellular matrix (ECM). Furthermore, we show that ICT fibroblast dysfunction is a unifying feature found in RD patients, even when the RD clinical presentation is caused by distinct genetic syndromes.

Accelerated pork salting using needle electrode-derived pulsed electric fields

This study aimed to evaluate the effects of pulsed electric field (PEF) pretreatment on the NaCl content, protein composition, and microstructure of pork during the marination process. The results showed that needle PEF could promote salt penetration into the center of pork pieces. Under optimal PEF conditions (3.0 kV/cm, 200 Hz, and 2400 pulses), the marination time could be reduced by almost 12 h. Protein characterization also revealed that PEF pretreatment changes myofibrillar protein properties by promoting salt penetration toward the center of pork. Furthermore, microstructural analysis demonstrated that the enhanced marination effect could be attributed to the PEF treatment-induced expansion of gaps between muscle bundles. Industrial relevanceIn this study, a PEF-assisted curing technique significantly (P < 0.05) improved salt penetration into the center of pork. Reducing the differences between internal and external salt concentrations can produce a more homogeneous marinade and reduce the marination time. Our findings suggest that PEF pretreatment is a promising and effective pretreatment technique for curing meat products.

Lingual adaptations of the Tarentola annularis with new insights into its papillary system adaptations: Ultrastructure, histochemistry, and immunohistochemical observations

Our research aims to conduct a comprehensive ultrastructural, histochemical, and immunohistochemical examination of Tarentola annularis' tongue, utilizing various techniques such as light, scanning electron microscopy, and morphometric analysis. The complex papillary system consisted of four conical subtypes and one filiform type. The apex carried three conical subtypes (elongated, quadrilateral, and round); the midtongue carried two papillary types (quadrilateral conical and rectangular pointed filiform); and the hindtongue carried two conical subtypes (quadrilateral and elongated serrated). The dorsal papillary surface carried little taste pores on the foretongue and taste buds on the midtongue. The foretongue had a slightly stratum corneum that spread to coat the papillae, while the mid- and hindtongue did not. The glands are absent from the foretongue but are found in the interpapillary spaces of the mid- and hindtongue. Histochemical analysis reveals the presence of collagen fibers in the muscle bundles and the papillary core. The midtongue glands exhibited a strong reaction to AB and PAS, while the hindtongue showed moderate AB positivity and strong positive PAS. The cytokeratin expression in the foretongue papilla was positive, whereas the papillae in other regions were negative. The Tarentola annularis exhibits distinctive lingual structural characteristics due to its varied feeding habits influenced by available food particles.

Histological morphology and gene expression in the digestive system of Procambarus clarkii

To unravel the intricate morphological structure and functional aspects of the digestive system in Procambarus clarkii, this study employed histology and transcriptome sequencing techniques for a comprehensive analysis of its digestive system. The investigation revealed that the digestive system of P. clarkii comprises the esophagus, stomach (including cardiac and pyloric regions), caeca, midgut, hindgut, and hepatopancreas. The esophageal lumen displayed an "X" shape, with clearly visible radial muscle bundles within the connecting tissues. The internal architecture of the stomach and intestines mirrored that of the esophagus. Notably, the pyloric region of the stomach exhibited a comb-like structure, which facilitated food selection and filtration. The caeca showcased a larger lumen within the intestines, while the hindgut displayed smaller folds. The hepatopancreas, representing the digestive glands, demonstrated predominant bilaterally symmetrical features, encompassing the midgut on both sides. It consisted of multi-stage branching hepatic ducts, crucial for digestion and absorption. Transcriptomic analysis of the digestive system revealed significant gene expression in the esophagus, stomach, caeca, midgut, hindgut, and hepatopancreas, with 23,006, 22,208, 23,485, 23,196, 22,781, and 21,375 genes expressed, respectively. Moreover, tissue-specific expression was observed in 161, 459, 374, 547, 337, and 1080 genes. Additionally, a subset of 447, 453, 553, 506, 433, and 711 genes exhibited high expression levels. Further analysis led to the identification of 36 digestive enzyme genes across six distinct digestive tissues, categorized into three groups: carbohydrate metabolism, lipid breakdown, and protein metabolism. In conclusion, this study provides a comprehensive understanding of the morphological structure, gene expression characteristics, and classification of digestive enzyme genes in the digestive system of P. clarkii. These findings lay a solid foundation for future investigations on the digestive physiology and food digestion in P. clarkii.

Immunological and molecular evaluation of zoonotic metacercarial infection in freshwater fish: A cross-sectional analysis

Improperly cooked fish, carrying active metacercariae (MCs), can pose a significant risk for transmitting fish-borne zoonotic trematodes (FBZTs) to human consumers. This study aimed to enhance our understanding of FBZTs by conducting a comprehensive cross-sectional analysis involving various fish species, such as Nile tilapia (Oreochromis niloticus), African catfish (Clarias gariepinus), and red-belly tilapia (Tilapia zillii). These fish specimens were collected from distinct Egyptian governorates, specifically Giza, Kafr al-Shaykh, and Fayoum. The recovered flukes from experimentally infected domestic pigeons were identified as Prohemistomum vivax, Haplorchis pumilio, and Pygidiopsis genata based on morphological features. Furthermore, the identity of the retrieved adult flukes was confirmed using three species-specific primers for PCR amplification and sequencing analysis of the ITS rDNA region and have been deposited in GenBank with the following accession numbers: P. vivax (OR291421.1 and OR291422.1), P. genata (OP099561.1), and H. pumilio (OM439581.1-OP090510.1).Quantitative real-time PCR targeting the immunological genes Tumor Necrosis Factor-alpha (TNF-alpha) and Interleukin-1 (IL-1Β) was employed to compare the cellular immune response between infected with EMCs and uninfected O. niloticus. The results indicated a significant increase in TNF- and IL-1Β levels in FBZTs-infected vs un-infected fishes. Importantly, the presence of adult flukes and EMCs led to substantial histological alterations in both experimentally infected pigeons and naturally infected fish tissues. These changes included the necrosis of fish muscle bundles and a pronounced inflammatory reaction with muscular necrosis in the digestive tracts of experimentally infected pigeons.

Verrucous gastritis-like lesion in intramucosal Helicobacter pylori-uninfected signet ring cell carcinoma with poorly differentiated adenocarcinoma.

In Japan, accessible Helicobacter pylori (Hp) eradication therapy is associated with an increase in the prevalence of gastric cancers (GCs) in Hp uninfected stomachs. Signet ring cell carcinoma (SRCC) is the most common of these GCs. Intramucosal SRCC with poorly differentiated adenocarcinoma (PDA) occurring in Hp uninfected gastric mucosa is rare; furthermore, many Hp uninfected pure SRCCs exhibit discoloration and flat or slightly depressed lesions, and morphological elevation is relatively rare. We report a case of intramucosal SRCC with PDA with an elevated, verrucous gastritis-like lesion in a 57-year-old male patient. In the present case, the PDA area showed dense tumor cell growth and coexisting desmoplastic and fibrotic reactions. Histopathology and immunohistochemical staining identified extensive fibromuscular obliteration with smooth muscle bundles extending from the muscularis mucosa into the lamina propria. The patient underwent curative endoscopic submucosal dissection. The reporting and analysis of such rare cases may lead to a better understanding of the characteristics of advanced Hp uninfected GCs.

Physiology and biomechanics researches of the special preparedness and contention activity of highly skilled kayakers

Purpose — development of methodology for individual evaluating special fitness and competitive activity of highly skilled kayakers.&#x0D; The rationality of the rower’s movement structure is largely determined by the character of work and interaction of the posterior and anterior bundles of the deltoid muscle, which perform the rower’s arm movements during applying both “pulling” and “pushing” efforts. The following causes of individual rowing technique errors significantly affecting sports result were identified: general muscle rigidity, lack of sufficiently complete and timely muscle relaxation; untimely involvement of muscles in work (appearance of mutual activity zones of antagonist muscles); late start of muscle activity (inertial moments of movement of rower's body biolinks are not provided before water entrapment); protracted, too long muscle activity (movement is performed entirely at the expense of muscular activity, without the use of inertial and propelling forces); low speed of muscle engagement in work leading, as a rule, to the “drop” of efforts on the oar. Two groups of athletes with diametrically opposite levels of physical capacity development and one group, which was characterized by their uniform development, were distinguished. The first group was distinguished by the high indices of power and efficiency of the work performed while covering the competitive distance. Such athletes showed higher sports results on short distances. The second group was distinguished by high indices of the efficiency of applying efforts, symmetry of movements, and successful performances on long competitive distances. Such rowers were classified as athletes with predominant development of special endurance quality. The rowers of the third group differed in the average values of the above mentioned indices and demonstrated equal success on both short and long competitive distances. Athletes with preferential development of speed-strength qualities and rowers with an advantageous development of special endurance have no significant difference in speed of covering 500 m distance and heart rate. However, there are significant differences in other indices of special fitness. Rowers with even development of physical qualities have differences in all recorded indices compared to those of the first two groups.&#x0D; The individual peculiarities of rowers’ movement coordination during covering a competitive distance of 500 m were determined. All rowers are divided into two groups. The first group is characterized by rational coordination of movements at the beginning of the distance covering and pronounced disturbances in the work dynamics of the muscles of the body turn and the nature of effort applied to the oar at the end of the distance. In the second group, we encounter the opposite phenomenon: with an irrational movement structure at the beginning of the distance, there is a transition of work to a more correct character at the end of its covering. The most preferable option for increasing the efficiency of athletes’ technical preparation is the use of the methodology for designing generalized and individual models of motor action structure. Preparation of rowers with account for their predisposition to the formation of the most important components of sportsmanship is the most preferable option. When drawing up individual plans for the preparation of athletes, the coaches should take into account these practical recommendations and adhere to the recommended directions of training. Repeated examinations (four months later) revealed the effectiveness of managing the process of technical preparation of kayakers based on the correction of intermuscular coordination.

Pathological Study of Rare Case of Duodenal Leiomyosarcoma in a Labrador Dog

The leiomyosarcoma is a tumor of mesenchymal origin of smooth, malignant, slow-growing muscles. The present study reports a case of duodenal leiomyosarcoma in Labrador dog. A 6 year old black female Labrador dog with history off feed, vomition and melena brought for necropsy examination. Gross lesions revealed tennis ball size tumorus mass at the initial portion of duodenum resulting into the obstruction of intestinal lumen. Microscopically, duodenum with tumours mass revealed smooth muscle bundles arranged in all the directions having elongated blunt ended nuclei along with numerous blood vessels and mitotic figure which is indicative of leiomyosarcoma.

[Gastric hamartomatous inverted polyps: a clinicopathological analysis of five cases].

Objective: To investigate the endoscopic and histopathological features, diagnosis and differential diagnosis of gastric hamartomatous inverted polyp (GHIP). Methods: Five cases of GHIP were collected at the University Town Hospital of Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China, from May 2021 to May 2023. The endoscopic, pathological and immunohistochemical features of the 5 GHIP cases were analyzed. The relevant literature was reviewed. Results: There were 3 males and 2 females, aged from 49 to 60 years, with a mean age of 56 years. The lesions were located in the fundus and body of the stomach, and presented as polyps or masses under endoscopy. Microscopically, the lesions were mainly in the submucosa and consisted of lobulated or clustered gastric glandular epithelium surrounded by hyperplastic smooth muscle. In some areas, there were differentiated glandular elements mimicking the normal gastric mucosa. The irregularly dilated glandular elements in the center were lined by hyperplastic foveolar epithelium, while the glands in the periphery were fundic or pyloric glands. In addition, in some areas, the glands showed cystic expansion, disordered arrangement and lack of differentiation. The hyperplastic glandular epithelium included foveolar epithelium, fundic gland and pyloric gland. There were scattered neuroendocrine cells and smooth muscle bundles in the stroma. Immunohistochemically, the tumor cells were positive for MUC5AC, MUC6, Pepsinogen Ⅰ and H+/K+ ATPase β, but negative for MUC2. The scattered neuroendocrine cells were positive for synaptophysin, and the desmin stain highlighted hyperplastic smooth muscle bundles. One case was classified as type 2 gastric inverted polyp, and 4 cases were classified as type 3. Conclusions: GHIP is a rare gastric polyp with unique histological features. It should be distinguished from inverted hyperplastic polyp, gastritis cystica profunda, adenomyoma, hyperplastic polyps and well-differentiated gastric tubular adenocarcinoma, etc. Improving the understanding of its pathogenesis and diagnostic features can help avoid misdiagnoses.

PM2.5 exposure-induced senescence-associated secretory phenotype in airway smooth muscle cells contributes to airway remodeling

Fine particulate matter (PM2.5) has been linked to increased severity and incidence of airway diseases, especially chronic obstructive pulmonary disease (COPD) and asthma. Airway remodeling is an important event in both COPD and asthma, and airway smooth muscle cells (ASMCs) are key cells which directly involved in airway remodeling. However, it was unclear how PM2.5 affected ASMCs. This study investigates the effects of PM2.5 on airway smooth muscle and its mechanism. We first showed that inhaled particulate matter was distributed in the airway smooth muscle bundle, combined with increased airway smooth muscle bundle and collagen deposition in vivo. Then, we demonstrated that PM2.5 induced up-regulation of collagen-I and alpha-smooth muscle actin (α-SMA) expression in rat and human ASMCs in vitro. Next, we found PM2.5 led to rat and human ASMCs senescence and exhibited senescence-associated secretory phenotype (SASP) by autophagy-induced GATA4/TRAF6/NF-κB signaling, which contributed to collagen-I and α-SMA synthesis as well as airway smooth muscle remodeling. Together, our results provided evidence that SASP induced by PM2.5 in airway smooth muscle cells prompted airway remodeling.

Fiber‐Format Dielectric Elastomer Actuators by the Meter

AbstractDielectric elastomers in the shape of thin films are heavily investigated, but they do not produce beneficial strains and forces comparable to that of skeletal muscles without entailing extremely complicated fabrication processes, rendering their practical use limited. Here, a silicone elastomer fiber is reported that can be produced by the meter and turned into an actuator by a simple process entailing the injection of an ionic liquid as the inner electrode and dipping in an ionogel to form the outer electrode. The fibers range from 174 to 439 µm in outer diameter with wall thicknesses from 62 to 108 µm and can be produced by the meter with regular diameter and thickness. The mechanical properties of the fibers are unaffected by the electrodes and actuation strains of 10% can be achieved, in both dry and wet environments. The fiber actuator can be bundled to mimic human skeletal muscle bundles or used in folded configurations, rendering it ideal as a building block for macroscopic actuators that can be used for many products such as body‐compliant actuators and wearables.

Beef tenderization without exacerbating the cooking loss: The way of enzymatic deamidation

Tenderization of beef using proteolytic enzymes often leads to high water loss due to harsh structural disruption. This study first verified the enzymatic deamidation (protein-glutaminase, PG) in softening grass-fed steak texture without exacerbating the cooking loss. PG deamidation at the deamidation degree (DD) of 5% (d5) or 7% (d7) significantly increased the tenderness and softened the texture whereas they negligibly affected the cooking loss. The muscle bundles were loosed while fibers were thickened probably as the result of charge induced myofibril dissociation (increased myofibril fraction index) and intermolecular repulsion. Compared to papain, the effect of PG deamidation on the water mobility was minor, though it was still seen a slight conversion of bound water into immobilized water in high DD steaks (d5 and d7). PG deamidation hardly hydrolyze individual proteins but partially altered the tertiary structure of muscle proteins, resulting in a slight decrease in denaturation enthalpies of muscle proteins including myosin, collagen and sarcoplasmic protein. These results demonstrated that PG deamidation appeared to be a novel and promising strategy in meat tenderization.

The Controversy of Using Insufficient Great Saphenous Veins in Coronary Artery Bypass Grafting: A Comparative Morphological Analysis of Healthy and Insufficient Veins Related to the Possibility of Using Them as a Graft.

Despite advancements in coronary artery bypass grafting (CABG), the optimal choice of graft material remains a subject of investigation. This study aimed to comprehensively analyze the morphological characteristics of varicose veins, exploring their potential utilization in CABG compared to healthy veins. The study included 178 patients, categorized into two groups based on healthy and varicose veins. Morphological parameters, including maximum venous diameter, wall thickness, and specific changes in tunica intima (TI), tunica media (TM), and tunica adventitia (TA), were analyzed through microscopic evaluation. Varicose veins exhibited a significantly larger maximum venous diameter (p = 0.0001) and increased wall thickness (p = 0.0001) compared to healthy veins. Although varicose veins showed thickening in TI and TM, the differences were not statistically significant. Notably, disorganized smooth muscle bundles were more prevalent in varicose veins (p = 0.001), suggesting potential wall weakness. The absence of vasa vasorum in TA was significantly higher in varicose veins (p = 0.050), influencing vascularization considerations. The comparative morphological microscopic analysis of the specimens of healthy and varicose veins reveals significant differences between the groups, which make the conclusion of this study to plead for avoiding the use of varicose veins as a graft.

Olf413 an octopamine biogenesis pathway gene is required for axon growth and pathfinding during embryonic nervous system development in Drosophila melanogaster

ObjectiveNeurotransmitters have been extensively studied as neural communication molecules. Genetic associations discovered, and indirect intervention studies in Humans and mammals have led to a general proposition that neurotransmitters have a role in structuring of neuronal network during development. olf413 is a Drosophila gene annotated as coding for dopamine beta-monooxygenase enzyme with a predicted function in octopaminergic pathway. The biological function of this gene is very little worked out. In this study we investigate the requirement of olf413 gene function for octopamine biogenesis and developmental patterning of embryonic nervous system.ResultIn our study we have used the newly characterized neuronal specific allele olf413SG1.1, and the gene disruption strain olf413MI02014 to dissect out the function of olf413. olf413 has an enhancer activity as depicted by reporter GFP expression, in the embryonic ventral nerve cord, peripheral nervous system and the somatic muscle bundles. Homozygous loss of function mutants show reduced levels of octopamine, and this finding supports the proposed function of the gene in octopamine biogenesis. Further, loss of function of olf413 causes embryonic lethality. FasII staining of these embryos reveal a range of phenotypes in the central and peripheral motor nerves, featuring axonal growth, pathfinding, branching and misrouting defects. Our findings are important as they implicate a key functional requirement of this gene in precise axonal patterning events, a novel developmental role imparted for an octopamine biosynthesis pathway gene in structuring of embryonic nervous system.

An Innovative Histochemical Analysis of Aksaray Malaklý Dog Esophagus by Scanning Electron Microscopy (SEM)

Background: The esophagus of the Aksaray Malaklý Dog, a local breed, was examined using macroanatomical, histological, histochemical and SEM methods. Methods: The study examined 8 adult Aksaray Malaklý dogs (4 males, 4 females) that died of various reasons and were brought to Aksaray University Veterinary Faculty Animal Hospital for necropsy. Macroanatomical examination of the esophagus revealed that the esophagus started from the pharynx and was divided into three parts: pars cervicalis, pars thoracalis and pars abdominalis and ended in the cardia of the gaster. It was observed that the esophageal glands seen in the submucosa were located along the entire length of the organ and consisted of many mucous-character corpus glandulae and very few serous-character-secreting corpus glandulae. Result: The glands’ secretion characteristics in the Aksaray Malaklý dog’s esophagus were determined using three different staining methods (AB pH: 2.5; AB pH: 1.0 and PAS). Gordon Sweeth’s (GS) staining method showed good staining of reticular fibers. A positive reaction was observed throughout the entire organ, except for the lamina epithelialis, the wall of blood vessels and muscle tissue. The 4 layers (mucosa, submucosa, muscularis and adventitia) histologically distinguished in the cross-section of Aksaray Malaklý dog esophagus were also distinguished in the scanning electron microscopy findings. Esophageal glands in the submucosa, muscle bundles in the muscularis layer and abundant blood vessels in the adventitia were also observed. The esophagus examined shows significant histological similarities with those of other mammals, making this species reliable as an experimental model for digestive testing and research.

The tongue of the red-eared slider (Trachemys scripta elegans): morphological characterization through gross, light, scanning electron, and immunofluorescence microscopic examination

The red-eared slider (Trachemys scripta elegans) is renowned for its remarkable adaptations, yet much of its complex biology remains unknown. In this pioneering study, we utilized a combination of gross anatomy, scanning electron microscopy (SEM), light microscopy, and immunofluorescence techniques to examine the tongue’s omnivorous adaptation in this species. This research bridges a critical knowledge gap, enhancing our understanding of this intriguing reptile. Gross examination revealed a unique arrowhead-shaped tongue with a median lingual fissure and puzzle-piece-shaped tongue papillae. SEM unveiled rectangular filiform, conical, and fungiform papillae, with taste pores predominantly on the dorsal surface and mucous cells on the lateral surface of the papillae. Histologically, the tongue’s apex featured short rectangular filiform and fungiform papillae, while the body exhibited varying filiform shapes and multiple taste buds on fungiform papillae. The tongue’s root contained lymphatic tissue with numerous lymphocytes surrounding the central crypt, alongside lingual skeletal musculature, blood and lymph vessels, and Raffin corpuscles in the submucosa. The lingual striated muscle bundles had different orientations, and the lingual hyaline cartilage displayed a bluish coloration of the ground substance, along with a characteristic isogenous group of chondrocytes. Our research represents the first comprehensive application of immunofluorescence techniques to investigate the cellular intricacies of the red-eared slider’s tongue by employing seven distinct antibodies, revealing a wide array of compelling and significant findings. Vimentin revealed the presence of taste bud cells, while synaptophysin provided insights into taste bud and nerve bundle characteristics. CD34 and PDGFRα illuminated lingual stromal cells, and SOX9 and PDGFRα shed light on chondrocytes within the tongue’s cartilage. CD20 mapped B-cell lymphocyte distribution in the lingual tonsil, while alpha smooth actin (α-SMA) exposed the intricate myofibroblast and smooth muscle network surrounding the lingual blood vessels and salivary glands. In conclusion, our comprehensive study advances our knowledge of the red-eared slider’s tongue anatomy and physiology, addressing a significant research gap. These findings not only contribute to the field of turtle biology but also deepen our appreciation for the species’ remarkable adaptations in their specific ecological niches.