Anterior Part Research Articles

The Hounsfield Unit Values of Talar Subchondral Bone Predict Articular Cartilage Degeneration in Patients With Ankle Osteoarthritis.

Therapeutic strategies for ankle osteoarthritis (OA) are determined based on OA staging, alignment, and articular cartilage conditions. However, it is difficult to evaluate the degeneration of the remaining cartilage using imaging modalities. Subchondral bone plays a crucial role in maintaining cartilage homeostasis. Measurement of local Hounsfield unit (HU) values allows for the quantitative assessment of small changes in the subchondral bone. This study aimed to evaluate a relationship between the HU values of the subchondral bone and the histologic findings of articular cartilage in ankle OA. The talar articular surface was harvested from 14 ankles during arthroplasty. The talus was divided into anterior, middle, and posterior parts, and histologic specimens were prepared. Safranin O staining was performed and histologic findings were evaluated using the modified Mankin score. The regions of interest (ROIs) were set in the medial, central, and lateral regions of the specimens and computed tomography (CT) images, and the relationship between the HU values and histologic findings was analyzed. As OA progressed, cartilage defects increased. In conjunction with cartilage degeneration, the subchondral bone plate thickened, and the HU values increased. The HU value significantly and positively correlated with the modified Mankin score (r = 0.756), subchondral bone thickness (r = 0.674, P < .01), and trabecular bone area (r = 0.637). The cutoff HU values were 594 (sensitivity, 0.813; specificity, 0.944) for 3 points and 727 (sensitivity, 0.929; specificity, 0.782) for 11 points on the modified Mankin score. Significant correlations between HU values and cartilage degeneration in ankle OA were noted. Measuring HU values on CT images can be useful for evaluating the joint surface condition, including histologic findings of the remaining cartilage.

Dynamic balance and gait impairments in Parkinson's disease: novel cholinergic patterns.

The cholinergic system has been implicated in postural deficits, in particular falls, in Parkinson's disease (PD). Falls and freezing of gait typically occur during dynamic and challenging balance and gait conditions, such as when initiating gait, experiencing postural perturbations, or making turns. However, the precise cholinergic neural substrate underlying dynamic postural and gait changes remains poorly understood. The aim of this study was to investigate whether brain vesicular acetylcholine transporter binding, as measured with [18F]-fluoroethoxybenzovesamicol binding PET, correlates with dynamic gait and balance impairments in 125 patients with PD (mean age 66.89 ± 7.71 years) using the abbreviated balance evaluation systems test total and its four functional domain sub-scores (anticipatory postural control, reactive postural control, dynamic gait, and sensory integration). Whole brain false discovery-corrected (P < 0.05) correlations for total abbreviated balance evaluation systems test scores included the following bilateral or asymmetric hemispheric regions: gyrus rectus, orbitofrontal cortex, anterior part of the dorsomedial prefrontal cortex, dorsolateral prefrontal cortex, cingulum, frontotemporal opercula, insula, fimbria, right temporal pole, mesiotemporal, parietal and visual cortices, caudate nucleus, lateral and medial geniculate bodies, thalamus, lingual gyrus, cerebellar hemisphere lobule VI, left cerebellar crus I, superior cerebellar peduncles, flocculus, and nodulus. No significant correlations were found for the putamen or anteroventral putamen. The four domain-specific sub-scores demonstrated overlapping cholinergic topography in the metathalamus, fimbria, thalamus proper, and prefrontal cortices but also showed distinct topographic variations. For example, reactive postural control functions involved the right flocculus but not the upper brainstem regions. The anterior cingulum associated with reactive postural control whereas the posterior cingulum correlated with anticipatory control. The spatial extent of associated cholinergic system changes were least for dynamic gait and sensory orientation functional domains compared to the anticipatory and reactive postural control functions. We conclude that specific aspects of dynamic balance and gait deficits in PD associate with overlapping but also distinct patterns of cerebral cholinergic system changes in numerous brain regions. Our study also presents novel evidence of cholinergic topography involved in dynamic balance and gait in PD that have not been typically associated with mobility disturbances, such as the right anterior temporal pole, right anterior part of the dorsomedial prefrontal cortex, gyrus rectus, fimbria, lingual gyrus, flocculus, nodulus, and right cerebellar hemisphere lobules VI and left crus I.

A new species of the genus Subeucalanus (Copepoda: Calanoida: Eucalanidae) from the Sea of Oman

A new species of the genus Subeucalanus Geletin, 1976 (Copepoda: Calanoida: Eucalanidae), Subeucalanus dextrolateralis sp. nov., is described based on female and male specimens collected in the Sea of Oman in October 2019. The new species is placed in the S. pileatus species–group. Subeucalanus dextrolateralis sp. nov. differs from its congeners in the shape of the anterior part of the head and the spermathecae pattern in the female, the structure of the fifth leg in the male, and the right-sided position of the longest caudal seta in both sexes. Morphological characters of the ten known species of the genus Subeucalanus (including the new species) are discussed. A key to the species of this genus is provided.

Anatomical Position of the Mentonian Foramen in Relation to the Alveolar Ridge and Mandibular Base using Cone Beam Computed Tomography in Dentate Patients

Introduction: The mentonian foramen is an important structure of the anterior part of the mandible, referent in surgical procedures of the mandible, mainly of the interforaminal area. Therefore, for a more precise analysis of this anatomical structure we use Cone Beam CT scans, since it provides us with a three-dimensional image of higher quality of the maxillofacial massif as it does not present overlapping images, geometric distortion and false negatives that could increase the risk of iatrogenic lesions. Objective: To determine the distance of the mentonian foramen in relation to the alveolar ridge and the mandibular base by means of Cone Beam Computed Tomography of dentate patients. Methodology: The study was descriptive, cross-sectional and retrospective; 109 Cone Beam Computed Tomography scans of dentate patients were evaluated from March to October 2020, taken from the Maxillofacial Diagnostic Institute (IDM) Lima, Peru; between 18 and 50 years old, distributed in three age groups: 18 to 28 years old, 29 to 39 years old and 40 to 50 years old. The distances from the upper edge of the mentonian foramen to the alveolar ridge and from the lower edge of the mentonian foramen to the mandibular base were analyzed, taking into account sex and age group. For the statistical analysis, SPSS Statistics version 26.0 was used and the T student test for related tests was applied to evaluate the differences between the right and left sides, T student for independent tests to analyze the measures with the male and female sexes and ANOVA of one factor for the analysis with the age groups. All tests were performed at a significance level of 5%. Results: The mentonian foramen is closer to the mandibular base than to the alveolar ridge, whose means are 13.81mm and 14mm, respectively. The average distance was shorter in the 40 to 50 years age group and the female sex presented shorter distances. Conclusion: The mentonian foramen is 13.81mm above the mandibular base, the greatest distances were found in the male sex and the shortest distances in the 40 to 50 years age group.

Morphology and morphometry of the anterior cerebral-anterior communicating artery complex.

The variations of Cerebral arterial circle (Circle of Willis) are not rare. The study is done to assess the pattern of the component vessels of its anterior part with regard to Right- Left variations and compare with other studies. 56 formalin fixed cadavers were analyzed. The diameter, length and variations of the following vessels were observed: Anterior Cerebral Artery (proximal A1 segment to distal A2 segment) and anterior communicating artery. Statistical analysis was done by Statistica 14.0.1 software. 53.57% had normal anterior cerebral artery- anterior communicating artery complex. Length and diameter were slightly more on left side. Unilateral hypoplasia, Azygos and Tripple Anterior Cerebral Artery was present in 21.43%, 3.57 and 1.78% respectively. Aplastic, double and fenestration type anterior communicating artery were present in 5.3%, 8.92% and 1.78% respectively. Anatomical knowledge of variations should be updated regularly for neurosurgeons, radiologists and clinicians to avoid unexpected consequences.

Sperm characteristics of the Telorchiidae (Digenea, Plagiorchioidea): First ultrastructural data on Telorchis attenuatus an intestinal parasite of Trachemys scripta elegans

The ultrastructural features of the mature spermatozoon of Telorchis attenuatus (Digenea, Telorchiidae), an intestinal parasite of the red-eared turtle Trachemys scripta elegans (Testudines, Emydidae), are described using transmission electron microscopy (TEM). The mature spermatozoon of T. attenuatus is a filiform cell tapered at both ends and displays Bakhoum et al.’s type IV of digenean sperm cells. Spermatozoa of T. attenuatus have: (i) two axonemes of different lengths with the 9+'1' pattern of trepaxonematan Platyhelminthes, surrounded by a continuous submembranous layer of cortical microtubules at their anterior end, (ii) an external ornamentation of the plasma membrane following Quilichini et al.'s type 2 and associated with cortical microtubules, (iii) two bundles of parallel cortical microtubules with the maximum number situated in the anterior part of the sperm cell, (iv) spine-like bodies, (v) two mitochondria, and (vi) a large number of irregularly distributed glycogen granules. Furthermore, the morphology of the posterior spermatozoon extremity in T. attenuatus corresponds to the Quilichini et al.'s fasciolidean type. The results of the current study are especially compared to the existing information from other families within the superfamily Plagiorchioidea.

DESCRIPTIONS AND PHYLOGENETIC AFFINITIES OF TWO NEW SPECIES OF RHABDIAS STILES AND HASSALL, 1905 (NEMATODA: RHABDIASIDAE) FROM NORTH AMERICAN FROGS: ARE WE STILL ONLY SCRATCHING THE SURFACE?

Two new species of lung-dwelling nematodes are described from North American frogs: Rhabdias aurorae n. sp. from Rana aurora and Rhabdias conni n. sp. from Rana clamitans and Rana catesbeiana from Arkansas; the latter species was also found in Oklahoma and Georgia. Rhabdias aurorae n. sp. differs from other Nearctic congeners in the combination of the following characteristics: buccal capsule 22-25 μm wide, elongated tail covered with inflated cuticle, esophagus with prominent dilatation in anterior part and 6 small circumoral lips. Rhabdias conni n. sp. is morphologically closest to Rhabdias ranae Walton, 1929 and Rhabdias joaquinensisIngles, 1936; it differs from them in the shape of lateral pseudolabia, the dimensions of the body, and the egg size. Both new species were found to be significantly different from the Nearctic congeners in the nucleotide sequences of nuclear ribosomal DNA (18S-ITS-28S region), 12S, and CO1 mitochondrial genes. The 2 new species differ from other currently sequenced Nearctic congeners by 1.1-2.7% of nucleotide positions in the nuclear rDNA region, 1.3-3.4% in the 12S gene, and 3.4-9.4% in CO1 gene. Molecular phylogenetic analysis based on nuclear ribosomal DNA sequences placed both new species into the clade consisting of Nearctic and Neotropical Rhabdias spp. The position of Rh. aurorae n. sp. within the clade is uncertain because of a polytomy, but Rh. conni n. sp. is nested within the "Rh. joaquinensis complex" related to Rh. ranae and Rhabdias tarichaeKuzmin, Tkach, and Snyder, 2003. The phylogenetic analysis based on nuclear ribosomal DNA sequences has revealed 3 evolutionary host-switching events from anuran to caudatan hosts among Rhabdias spp. that occurred in the Nearctic and Palearctic. The molecular phylogeny also suggests that Rhabdias may have originally evolved in what is now Africa.

Effects of dexmedetomidine on depression-like behaviour in chronic restraint stress mice: Involvement of specific brain regions

It is crucial to develop novel antidepressants. Dexmedetomidine (DEX) can exert antidepressant effects, but its underlying mechanism remains unclear. We used chronic restraint stress (CRS) to induce depression-like behaviour in mice and administered low-dose DEX (2 μg/kg per day) during CRS modelling or one injection of high-dose DEX (20 μg/kg) after CRS. The results of the behavioural tests revealed that both methods ameliorated CRS-induced depression. The brain slices of the mice were subjected to immunohistochemical staining for c-fos and phosphorylated ERK (pERK). Results showed that the continuous low-dose DEX-treated group, but not the single high-dose DEX-treated group expressed less c-fos in the nucleus locus coeruleus (LC) with a mean optical density (MOD) of 0.06. Other brain regions, including the dentate gyrus (DG), pyriform cortex (Pir), anterior part of paraventricular thalamic nucleus (PVA), arcuate nucleus (Arc), and core or shell of accumbens nucleus (Acbc or Acbs), presented differences in c-fos expression. In contrast, the low-dose DEX-treated group exhibited three-fold greater pERK expression in the LC of the CRS mice, with a MOD of 0.15. Pir, cingulate cortex (Cg) and, anterior and posterior part of paraventricular thalamic nucleus (PVA and PVP) exhibited pERK expression differences due to distinct reagent treatments. These changes indicate that the responses of brain regions to different DEX administration methods and doses vary. This study confirmed the ability of DEX to ameliorate CRS-induced depression and identified candidate target brain regions, thus providing new information for the antidepressant mechanism of DEX.

Laparoscopic repair of a symptomatic right congenital morgagni hernia in an elderly patient: a rare case report

Morgagni hernia is a rare form of congenital diaphragmatic defect on the anterior part of the diaphragm with a prevalence of 2-3%. We report a case of a 70-year-old female who presented with burning chest pain, intermittent and colicky upper abdominal pain occasionally associated with nausea and vomiting, and constipation for 4 months. Imaging studies, including X-ray, ultrasound, CT scan, and MRI, were suggestive of a right-sided congenital Morgagni hernia. Late diagnosis of this condition in adults is extremely rare, and in the elderly, it is even rarer. The patient underwent successful laparoscopic diaphragmatic hernia repair with prosthetic mesh placement. The postoperative period was uneventful, and the patient was discharged on the fifth postoperative day. Minimally invasive surgical techniques provide definitive treatment for patients with uncomplicated Morgagni hernia cases, offering a shorter recovery time and a low complication rate.

Odorant transport in a hagfish

Odorant transport is of fundamental and applied importance. Using computational simulations, we studied odorant transport in an anatomically accurate model of the nasal passage of a hagfish (probably Eptatretus stoutii). We found that ambient water is sampled widely, with a significant ventral element. Additionally, there is a bilateral element to olfactory flow, which enters the single nostril in two narrow, laminar streams that are then split prior to the nasal chamber by the anterior edge of the central olfactory lamella. An appendage on this lamella directs a small portion (10–14%) of the overall nasal flow to the olfactory sensory channels. Much of the remaining flow is diverted away from the sensory channels by two peripheral channels. The anterior edge of the central olfactory lamella, together with a jet-impingement mechanism, disperses flow over the olfactory surfaces. Diffusion of odorant from bulk water to the olfactory surfaces is facilitated by the large surface area:volume ratio of the sensory channels, and by a resistance-based hydrodynamic mechanism that leads to long residence times (up to 4.5 s) in the sensory channels. With increasing volumetric flow rate, the rate of odorant transfer to the olfactory surfaces increases, but the efficiency of odorant uptake decreases, falling in the range 2–6%. Odorant flux decreases caudally across the olfactory surfaces, suggesting in vivo a preponderance of olfactory sensory neurons on the anterior part of each olfactory surface. We conclude that the hagfish has a subtle anatomy for locating and capturing odorant molecules.

Analysis of the Application Value of Dynamic Navigation Guidance in Oral Implantation.

To investigate the application of dynamic navigation guidance technology in different implantation scenarios, and to provide a scientific basis for the innovation and advancement of implantation techniques. Fifteen cases of patients with malocclusions admitted between January 2021 and February 2023 were selected as the study subjects. All patients underwent dynamic navigation-guided oral implantation interventions. CBCT scans were taken after implantation surgery to record deviations of implantation points, including implantation point deviation, endpoint deviation, and angle deviation. Dynamic navigation guidance effectively improves the reliability and stability of implantation in oral implant patients. CBCT effectively evaluated the state of the patient's periodontal implant, analyzed the state of the patient's lesion area, and improved the quality of implant intervention through CBCT guidance. The implantation point deviation was (0.407±0.193) mm, the endpoint deviation was (0.492±0.201) mm, and the implant angle deviation was (2.162±0.283)°. There was no significant difference in implantation point deviation in the anterior and posterior parts of the upper and lower jaws after intervention (P>0.05). However, there were significant differences in endpoint deviation and implant angle deviation among the anterior and posterior parts of the upper and lower jaws (P<0.05). Dynamic navigation guidance effectively improves the reliability and stability of implantation in oral implant patients. However, there is relatively greater endpoint deviation and implant angle deviation in the posterior part of the upper jaw.

Reduced interhemispheric transfer in older adults: Evidence from a divided visual field one-back task.

One of the pivotal structural changes observed in the ageing brain pertains to the corpus callosum, the largest neural pathway interconnecting the two cerebral hemispheres. Studies have highlighted the degeneration of the corpus callosum, particularly in its anterior segments, as individuals age. This prompts an essential question regarding the potential functional repercussions of these structural changes on interhemispheric communication among older adults. Two experiments were conducted to explore potential compromises in the interhemispheric transfer of visual working memory (VWM) in older adults. Both young individuals (aged 18-28 years) and healthy older adults (aged 65-85 years) engaged in modified versions of the one-back paradigm. In this task, stimuli were sequentially presented in either the left or right hemifield, and participants indicated whether each stimulus matched the preceding one. Notably, when two stimuli are matched, they could appear either in the same hemifield or in opposite hemifields. The results revealed that, in comparison to young adults, older adults demonstrated a significant increase in matching errors when the two stimuli were presented in opposite hemifields rather than the same hemifield. This new finding strongly suggests a reduced interhemispheric transfer of VWM in older adults, potentially attributed to age-related atrophy in the anterior part of the corpus callosum. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Skeletal Muscle Complex Between the Vagina and Anal Canal: Implications for Perineal Laceration.

The anatomy of the skeletal muscles located between the vagina and anus is important during complex obstetric laceration reconstructions. We aimed to clarify the composition of skeletal muscles located between the vagina and anal canal and their three-dimensional configuration relevant to perineum repair. This observational study involved ten female cadavers. An anatomical dissection was performed to observe the muscles around the vagina and anal canal. Immunohistological analysis of the midsagittal section was performed to clarify the composition of the muscles, and dissection was performed to correspond to the cross-section. Wide-range serial sectioning and three-dimensional reconstruction were used to support these findings histologically and visualize the three-dimensional arrangement. The region between the vagina and anal canal included the anterior part of the external anal sphincter, superficial transverse perineal muscle approaching from the lateral side, and levator ani, located cranially. They converge three-dimensionally in the median from each direction, forming a muscle complex between the vagina and anal canal. The medial region between the vagina and anal canal in those giving birth includes a skeletal muscle complex formed by the confluence of the external anal sphincter, anterior bundle of the levator ani, and superficial transverse perineal muscle. In cases of severe perineal lacerations, these muscles could be injured. The anatomical knowledge that a part of the levator ani forms a muscle sling anterior to the anal canal is particularly important for obstetricians and gynecologists repairing obstetric lacerations and treating pelvic floor disorders.

Single versus Double Plate Fixation in Condylar Neck Fractures: Clinical Results and Biomechanics Simulation.

The open reduction of mandibular condyle neck fractures is difficult due to the limited surgical field and complex facial nerve structures. The most effective fixation method for narrow fractured segments is debated as standard double four-hole plate fixation is often not feasible. This research compared bone stability and force resistance between single-long-plate and double-short-plate fixations using clinical outcomes, a Sawbones mandible model, and finite element analysis. In patients with condyle neck fractures, nine were fixed with single-long-plate and twelve with double-short-plate fixations, with no significant differences in malocclusion and facial palsy rates. In compression tests with a Sawbones model, displacements in the posterior part were similar in both fixation groups. In contrast, the anterior part had significantly higher displacements in the single-long-plate group. Finite element analysis showed higher displacements in both anterior and posterior parts in the single-plate group compared to the double-short-plate group. Maximum stresses were at the second screw hole in single-long-plate fixation and the turning point of the upper plate at the condyle neck in double-short-plate fixation. Double-short-plate fixations demonstrated better stability and force resistance than single-long-plate fixations.

A Comparative Study on the Efficacy and Safety of 10% Topical Minoxidil versus 5% Topical Minoxidil in the Treatment of Male Pattern Hair Loss

Abstract Background Androgenetic alopecia is a genetically disorder characterized by the gradual conversion of terminal hairs into vellus hairs, called miniaturized hairs. It is an extremely common disease that affects men and women. Specifically, DP cells that are the main regulators of hair growth and are the only site of 5α-DHT action. Male-pattern hair loss; Male note gradual recession of the frontal hair line early in the process. Men present with gradual thinning in the temporal areas, producing a reshaping of the anterior part of the hair line. Aim of this Study To evaluate and compare topical minoxidil 10% versus topical minoxidil 5% in the treatment of MPHL as regards the efficacy, safety and side effects. This study included 51 patients with MPHL divided into 2 groups received topical minoxidil 5% 1ml twice daily for 6 months and the second group received topical minoxidil 10% 1ml twice daily for 6 months. Patients and Methods: Results The current study revealed that there was significant difference between the studied groups as regard the percentage of improvement in Frontal Total hair count with superiority for 10% group. But the improvement in other parameters were comparable between the studied groups. Comparison of treatment response in both groups revealed nearly the same efficacy of both concentrations of topical minoxidil 5% and 10% in MPHL, higher concentration more than 5% could decrease the compliance and the tolerance. Conclusion We found that using higher doses of topical minoxidil was associated with higher improvement in frontal total hair count and higher side effects.

Registration of jaw centric relation with different deprogramming devices

BACKGROUND: There are several methods to register jaw centric relation for diagnosis and therapy of dysfunctional disorders of the temporomandibular joint. However, there is insufficient information in the literature regarding the choice of the optimal way to determine this indicator. AIM: To compare different methods for recording jaw centric relation according to the data of the computed tomography of temporomandibular joint. MATERIALS AND METHODS: The study includes participants with increased abrasion of hard tooth tissues and symptoms of musculoskeletal dysfunction of the temporomandibular joint. The main group (80 people) has been recorded jaw centric relation using deprogramming devices (Lucia jig — 1stsubgroup, Kois deprogrammer — 2ndsubgroup, sheet calibrator — 3rd subgroup, deprogrammer in combination with M. Rocаbado kinesiotherapy elements — 4th subgroup). The control group included 20 participants, who had not had deprogramming before registration of jaw centric relation. The results were monitored using computed tomography of temporomandibular joint and subsequent assessment of the sizes of the TMG articular gap in the coronary and sagittal sections at 3 stages of the study: diagnostic, after registration of jaws central relation and prosthetic treatment and 6 months after prosthetic rehabilitation. Since there were no more than 50 observations in each group, the Shapiro–Wilk W-test was used to verify compliance with the norm. RESULTS: According to the data obtained, the parameters of the temporomandibular joint gap have changed in the main group of the 1th subgroup, where indicators are approaching the physiological norm (98% of cases). In the 2ndsubgroup, 90% of the participants show a tendency to conform to the physiological norm. The exception is 10% of the participants with no tendency of improvement. The smaller part (75%) of the participants of the 3rd subgroup observed compliance of the parameters of the articular gap with the criteria of the norm. The dimensions of the anterior part of the articular gap of the temporomandibular joint exceed the dimensions of the distal part, which indicates the anterior position of the temporomandibular joint. Some patients in this group (25%) showed no positive results of computed tomography measurements after jaws centric relation registration. In the 4th subgroup, the patients returned to normal values (100% of the cases). The positive effect of prosthetic treatment and restoration of the position of the articular heads of the temporomandibular joint were obtained in 45 % of the participants in the control group. However, in 55% of the participants the location of the articular gap of the temporomandibular joint did not improve. CONCLUSIONS: Lucia jig in combination with the M. Rokabado’s complex of cranial-postural kinesiotherapy is the most effective method to register jaw centric relation within this study. The remaining methods are also applied among prosthetic dentists and gnathologists. However, in each clinical situation, it is necessary to consider temporomandibular joint pathology indications, type and degree of severity as well as the technical and financial capacity of both doctor and patient.

A new mud lobster of the genus Thalassina Latreille, 1806 (Crustacea: Decapoda: Gebiidea: Thalassinidae) from the mangrove forest of the Cần Giờ Mangrove Reserve, South Vietnam

A new species of mud lobster of the genus Thalassina Latreille, 1806 (Decapoda: Gebiidea: Thalassinidae), Thalassina cangioensis sp. nov., is described from mangrove forests of the Cần Giờ Mangrove Biosphere Reserve, located in the Soài Rạp River delta in the downstream of the Dongnai-Saigon River system, South Vietnam. The new species is morphologically mostly similar to T. anomala (Herbst, 1804) in the shape of the rostrum and anterior part of the carapace and the presence of a single median tubercle on pleonal sternites II–V. However, it differs in the strong spinulation on the posterior part of the carapace, the armature of the pereopods I (chelipeds), and the presence of spines on the proximal part of the pleopod I in males. The shape of the pleopod I in males of the new species is mostly similar to that of T. squamifera, but it can be distinguished by the downwardly bulging median part at the tip, which is unique to the genus. Molecular genetic analysis revealed that the new species strongly genetically diverged (by the mitochondrial COI gene marker) from all currently sequenced species of the genus Thalassina, such as T. anomala, T. gracilis, T. kelanang and T. squamifera.

In-vitro safety assessment of meropenem on human retinal pigment epithelium (RPE)

PurposeEndophthalmitis is a severe infection accompanied by inflammation that affects the anterior and posterior parts of the eye. It is typically treated with a combination of antibiotics that cover various microorganisms. However, retinal pigment epithelium (RPE) cells are highly susceptible to damage from intravitreal injection therapy. This study aimed to investigate the impact of clinically relevant concentrations of meropenem (alone or in combination with vancomycin) on the viability and inflammation of RPE cells. DesignIn-vitro Study. MethodsRPE cells from passages 5–7 were treated with different concentrations of meropenem (1/4x, x, and 4x; [x = 16 mg/L]), vancomycin (30 mg/L), and meropenem (x) plus vancomycin for 24 h. The morphology assessment and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay were performed to evaluate cytotoxicity due to drug treatment. Real-time PCR was used to measure the relative expression of apoptotic genes (BCL-2 and BAX) and inflammation biomarkers (IL-1b and IL-6). ResultsMeropenem (alone or in combination with vancomycin) did not have any significant effect on RPE cell morphology, density, and viability. Gene expression analysis confirmed these results, showing no significant changes in the BCL-2/BAX ratio in drug-treated RPE cells compared to controls. Treatment with meropenem significantly induced the expression of IL-1b at all studied concentrations. Additionally, at concentrations of x and 4x, it also significantly increased the expression of IL-6, which was dose-dependent. However, this effect was not observed with vancomycin alone or in combination with meropenem. ConclusionsThe results of this study suggest that meropenem, either alone or in combination with vancomycin, does not induce RPE cytotoxicity. There was an upregulation of IL-1b and IL-6 in meropenem monotherapy, the clinical implication of which should be elucidated in future in-vivo or clinical studies.

High delta angle after reverse total shoulder arthroplasty increases stresses of the acromion: biomechanical study of different implant positions

BackgroundAcromial fractures after Reverse Total Shoulder Arthroplasty (RTSA) are a common complication. Nevertheless, only a few studies have identified risk factors for acromial fractures after RTSA. High delta angle (combination of inferiorization and medialization of the center of rotation) after RTSA was identified as a risk factor in recent studies. The aim of this study was the biomechanical exploration of different delta angles and implant configurations with regard to the acromial stress. MethodsIn a rigid body model of the upper extremity muscle, forces of the deltoid muscle were calculated before and after implanting RTSA in different arm and implant positions. The deltoid muscle was divided into an anterior, middle, and posterior part. Implant positions of the glenoid components were changed in the medialization, lateralization and inferiorization of the center of rotation (COR) as well as lateralization of the humeral component. Further, in a finite element model of the upper extremity, the stresses of the acromion in the same implant design configurations were measured. ResultsDifferences in acromial stress between different delta angle model configurations were observed. Lateralization (5 mm, 10 mm) of the glenosphere reduced maximal acromial stress by 21% (1.5 MPa) and 31% (1.3 MPa), respectively. Inferiorization (5 mm, 10 mm) of the glenosphere increased maximal acromial stress by 5% (2.0 MPa) and 15% (2.2MPa), respectively. Changes in positioning the humeral component was found to have the highest impact in this model configuration. A 10 mm lateralized humeral component reduced acromial stress by 37% (1.2 MPa) while in the 6 mm medialized configuration, an increase in acromial stress by 83% (3.48 MPa) was observed. There was a high correlation between delta angle and acromial stress (R-squared = 0.967). ConclusionImplant design configuration has an impact on the acromial stress. High delta angles correlate with an increase in acromial stress. Both lateralization of the COR and the humerus decreased the acromial stress in our study. The lateralization of the humerus has the highest impact in influencing acromial stress. Due to contrary results in the current literature, further studies with focus on the acromial stress influenced by different anatomical variants of the shoulder and the acromion are needed before a clinical recommendation can be made.

Assessment of Factors Associated with Mandibular Anterior Crowding in Mixed Dentition

ABSTRACT Introduction: Dental crowding can be defined as a disparity in the relationship between the tooth size and arch length, which results in imbrication and rotation of teeth. Crowding of permanent teeth, especially in the anterior part of the mandible, is believed to be the most frequent form of malocclusion in children. The appropriate age for treatment of crowding is the late mixed dentition period. Aim: To assess and compare the dental and skeletal factors associated with early crowding and non-crowding in children with mixed dentition. Methodology: This experimental cross-sectional study was conducted in Mangalore within 24 months. A total of sixty subjects between the age group of 7–10 years of both sexes were included in the study, in which the experimental group includes 30 subjects with mandibular crowding and the control group includes 30 subjects without lower anterior crowding. A comparison of model analysis parameters between the crowding group and the non-crowding group was done using Student’s t-test. Any P-value of ≤0.05 is considered statistically significant. Results: The result showed that dental parameters like total incisor width were greater and intercanine width was found to be reduced in the crowding group, whereas arch diameter was found to be increased in non-crowding group, which was statically significant (P-value). Skeletal parameters like SNA and SNB were found to be significantly decreased in crowding individuals (P-values of 0.011 and 0.04, respectively). Conclusion: The total incisor width was found to be greater in the crowding group when compared to the non-crowding group, and this could be one of the reasons for the cause of crowding in the early mixed dentition period. The intercanine width and arch diameter were reduced in the crowding group when compared to the non-crowding group. Crowding in the permanent dentition may either be eliminated or at least severity can be reduced if interceptive orthodontics is initiated at an early stage in such children.