Migration and Histologic Effects of Visible Implant Elastomer (VIE) and Passive Integrated Transponder (PIT) Tags in the Marine Toad (Rhinella marina)

Passive integrated transponder (PIT) and visible implant elastomer (VIE) tags are commonly used to identify reptiles, amphibians, and fish. Despite reports of good retention rates and little to no negative effect on survival time, migration remains a concern and histologic changes have not been widely evaluated. Fifty-six wild-caught marine toads (Rhinella marina) were marked with a PIT tag in the left caudal thigh and a VIE tag over the right gastrocnemius muscle prior to transport to the North Carolina Zoo. Fourteen toads were then humanely euthanized on day 9, 15, 32, and 62 for postmortem examination and histopathology which were compared to 10 control toads with no tags. All PIT tags were functional and 95% remained at the insertion site with minimal to no histologic changes. Externally, 48% of VIE tags were visible through the skin at the original site of injection under fluorescent or UV light. Upon gross examination of the tissues, VIE tags had an overall retention rate of 62% at the injection site, with similar retention rates across time points. Migrated VIE material was visible grossly and histologically in the kidneys of 98% of toads and along the right leg, proximally and distally, in 25% of toads. VIE material was also found sporadically in mesentery, colon, and free in the coelomic cavity. Histologically, VIE material in the skin was surrounded by minimal to mild granulomatous inflammation while in the kidney it was associated with dilation of the small vessels, edema, and granulomatous nephritis that progressed in severity over time. Based on these findings, the authors recommend the use of PIT tags over VIE tags for identification of adult anurans, when feasible.

Histologic Findings in Surgical Pathology Specimens From Individuals Taking Masculinizing Hormone Therapy for the Purpose of Gender Transition: A Systematic Scoping Review

Context.— Transgender men and transmasculine persons experience a discordance between the female sex they were assigned at birth and their gender. They may choose to take hormone therapy and/or undergo surgery to masculinize the body. Understanding the common (and less common) histologic changes present in patients taking masculinizing hormones will empower pathologists to better serve this unique patient population. Objective.— To summarize histologic findings in surgical pathology specimens from persons taking masculinizing hormones as a part of gender transition. Data Sources.— A systematic review of the OVID Medline and PubMed databases was performed to identify all studies describing histologic findings in surgical pathology specimens from transgender men from January 1946 to January 2021. Conclusions.— Publication in this area has markedly increased in the last 2 decades. However, most of the studies identified were descriptive and case reports describing changes seen in specimens removed as a part of masculinizing surgical procedures. Benign histologic findings include stromal hyalinization and epithelial atrophy in the breast, polycystic ovarian syndrome–like changes in the ovary, and transitional cell metaplasia in the cervix. The most commonly reported neoplastic finding was adenocarcinoma of the breast, with rare cases of ovarian, endometrial, cervical, vaginal, pituitary, pancreatic, and cardiovascular neoplasia also reported. Ongoing research in this area is needed to better characterize the histologic findings in persons taking masculinizing hormones to provide a deeper understanding of the effect of these treatments on different tissues and facilitate better patient management.

Histological Tracking into the Third Dimension

Using a novel three-dimensional (3D) approach, we tracked histological changes to elucidate the earliest stages of renal clear cell neoplasia in normal kidney tissue of patients with von Hippel-Lindau (VHL) disease. Tissue blocks of interest were procured, serially sectioned, and 3D reconstruction of the entirety of pathologic events was performed. The results reveal an abundance of foci with aberrant clear cell proliferation that initially develop along the tubular lining, but have the potential to aggregate within individual tubules. This stage is followed by the extension of clear cell aggregates beyond the tubular basement membrane, which allows for the recruitment of angiogenesis derived from interstitial vasculature. The results suggest that the most frequent pathologic event in VHL kidneys is the presence of isolated or aggregated clear cells within the tubular epithelium, potentially developing further into a protracted process of neoplasia. The abundance of independent pathologic events in VHL kidneys confirms developmental mechanisms to precede tumor initiation. To our knowledge, this is the first report demonstrating that tracking of histologic changes in the 3rd dimension enables the confirmation of the sequence of events from the earliest pathologic change in the VHL kidney to the neoplastic stage. This approach is not only useful for visualization and quantification of pathologic changes but also for targeted sampling allowing selective analysis of the earliest stages of clear cell carcinogenesis.

In Vivo Treatment Efficacy of Essential Oil Isolated from Seeds of Momordica charantia in Streptozotocin Induced Diabetes Mellitus

Background: All parts of Momordica charantia L have potential hypoglycemic property in reversing the metabolic disorder of diabetes mellitus. But there exists a need for preparing an effective and safer formulation of active phytochemical. We have also reviewed certain patents on such preparatory methods for Momordica charantia L and analysis. Objective: The objectives were isolation of the essential oil from the seeds of Momordica charantia L, analysis of its phytochemicals and study of their anti-diabetic effects. Methods: The essential oil was isolated by hydro distillation method, analyzed for phytochemicals by GC-MS and tested its acute toxicity in rats. Anti-diabetic effects were evaluated in Streptozotocin induced diabetic rats with 17.5 and 55 mg/kg b.wt of essential oil by evaluating blood glucose, serum lipid profile, liver glycogen, protein and other serum markers such as ALT, AST, ALP, urea and creatinine. The histologic changes in the liver, pancreas and kidney were evaluated using Haematoxylin and Eosin staining. Results : The phytochemicals, having hypoglycaemic and insulin induction potency were identified in the GC-MS analysis. A highly significant (p≤0.01; p≤0.001) reduction in blood glucose was resulted for 17.5 mg/kg and 55 mg/kg essential oil treatments respectively. The diabetes associated metabolic alterations (p≤0.001) observed in diabetic control rats such as lipid profile, enzymes, glycogen, protein, urea and creatinine were normalized upon treatment with essential oil. The histologic changes in vital organs reversed in treated rats. Conclusion: The essential oil of Momordica charantia L. seed has promising potency to normalize the metabolic changes of type II diabetes mellitus.

Recurrent Schowannoma With Extensive Xanthomatous Changes: A Case Report

Schwannoma is one of the most common benign intracranial tumors, which originates from the Schwann cells of neural structures in the upper part of the vestibular branch of the eighth cranial nerve. This report describes a 64-year-old woman with headache and vertigo who had a past surgical history of acoustic schwannoma about 10 years ago. The patient underwent excisional surgery. Histological examinations revealed schwannoma with extensive xanthomatous changes. Immunohistochemistry staining confirmed the diagnosis. Base on the diagnosis, the patient received no more treatment. After 6 months of close follow-up examinations, no recurrence and complication were observed. Schwannoma could be seen with a vast variety of histologic changes. Recurrence of Schownnoma is uncommon in patients without neurofibromatosis, but it should be considered in a proper clinical context.

Intravenous, Intratracheal, and Intranasal Inoculation of Swine with SARS-CoV-2

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the susceptibility of animals and their potential to act as reservoirs or intermediate hosts for the virus has been of significant interest. Pigs are susceptible to multiple coronaviruses and have been used as an animal model for other human infectious diseases. Research groups have experimentally challenged swine with human SARS-CoV-2 isolates with results suggesting limited to no viral replication. For this study, a SARS-CoV-2 isolate obtained from a tiger which is identical to human SARS-CoV-2 isolates detected in New York City and contains the D614G S mutation was utilized for inoculation. Pigs were challenged via intravenous, intratracheal, or intranasal routes of inoculation (n = 4/route). No pigs developed clinical signs, but at least one pig in each group had one or more PCR positive nasal/oral swabs or rectal swabs after inoculation. All pigs in the intravenous group developed a transient neutralizing antibody titer, but only three other challenged pigs developed titers greater than 1:8. No gross or histologic changes were observed in tissue samples collected at necropsy. In addition, no PCR positive samples were positive by virus isolation. Inoculated animals were unable to transmit virus to naïve contact animals. The data from this experiment as well as from other laboratories supports that swine are not likely to play a role in the epidemiology and spread of SARS-CoV-2.

Meningoencephalomyelitis in domestic cats: 3 cases of Pasteurella multocida infection and literature review

Neurologic diseases are common in domestic cats, and infectious agents are suspected to be the primary cause in 30–45% of cases. Among infectious etiologies, those of bacterial origin are only sporadically characterized in the literature, with few of these reports correlating gross and histologic findings with confirmatory bacteriologic identification. Here, we describe bacterial meningitis and meningoencephalomyelitis associated with Pasteurella multocida in 3 domestic cats. Purulent exudate expanding the cerebral meninges was grossly evident in 2 of the cases. In all 3 cases, histologic changes included multifocal suppurative-to-necrosuppurative meningitis and/or meningoencephalomyelitis of variable severity. Intralesional colonies of gram-negative, short rod-shaped to coccobacillary bacteria were evident histologically in only 1 case. P. multocida was confirmed by routine bacteriologic culture in all cases. Based on our cases, we hypothesize that the upper respiratory system serves as the main portal of entry for P. multocida, leading to invasion of the central nervous system and possible systemic hematogenous dissemination. A case series of meningoencephalomyelitis associated with P. multocida infection in cats has not been reported previously, to our knowledge. We also review briefly other causes of meningoencephalomyelitis in cats.