Specific Staining Research Articles

Sclerosing Odontogenic Carcinoma: A Unique Odontogenic Carcinoma with Metastatic Potential.

The recent World Health Organization (WHO) classification of odontogenic tumours defines Sclerosing Odontogenic Carcinoma (SOC) as a rare primary intraosseous carcinoma (PIOC) of the jaws. With the exception of one case, there have been no cases of SOC with metastatic disease. We report a unique case of SOC with neck node metastases, further expanding the clinical, radiological and histological spectrum of this rare intriguing tumour. A 52-year-old female presented with a destructive radiolucent lesion of right mandible. Incisional biopsy was interpreted as desmoplastic ameloblastoma. The segmental mandibulectomy specimen was histologically consistent with SOC with positive anterior margin. Further resection with neck dissection revealed positive right levels IB and IIA nodes. Immunohistochemistry and Fluroscent In Situ Hybridization (FISH) were performed to confirm the diagnosis. The tumour was positive for CK5, p63, p40 and negative for CK19, CK20, CK7, SOX-10, S100, ER, PR, BRAFV600E, and EWSR1 gene rearrangements. Ki67 was 15%. To avoid confusion with PIOC, a high grade squamous cell carcinoma of the jaws with poor prognosis, SOC may be best defined as a rare infiltrative and locally aggressive odontogenic carcinoma with metastatic potential but with a reasonably favourable outcome. SOC shares similar histologic features with many benign and malignant tumours. An appropriate panel of immunohistochemical markers, in conjunction with special stains and molecular studies can help refine the differential diagnosis. It appears that a Ki67 proliferation index of more than 10%, may pose a risk for nodal metastasis and may assist in planning the clinical management. To achieve lower rates of positive margins and tumour recurrence, a wider resection margin (more than a centimetre) is recommended.

Detection of viral antigen and inflammatory mediators in fatal pediatric dengue: a study on lung immunopathogenesis

IntroductionThe dengue virus (DENV) is the etiological agent that causes dengue fever illness, an arbovirus with a major endemic potential that has become increasingly prevalent in Brazil and has already been associated with fatal cases in children. DENV has tropism for several organs, including lungs causing pulmonary complications. The aim of this article was to evaluate the inflammatory and histopathological profile of the lung tissue of three fatal cases of children infected with DENV, which represents a group more susceptible to fatality due to its incomplete development.MethodsHistopathological analysis was carried out using Hematoxylin and Eosin staining and special stains. While the characterization of the inflammatory response and cellular expression was done by marking the viral protein, macrophages, lymphocytes and pro-inflammatory cytokines.Results and discussionThe results confirm that vascular dysfunctions such as hemorrhage, vascular congestion and edema associated with a mononuclear infiltrate were observed in all three cases. In addition, the presence of viral replication and increased expression of inflammatory markers were also observed. Such findings contribute to the study and description of dengue, especially its effects on lung tissue.

Analysis of Histochemical Characteristics of Submandibular Gland of the Bactrian Camel

The ultrastructure of submandibular gland (SMG) of Bactrian camels was observed by a transmission electron microscope. Routine HE staining, special staining combined with immunohistochemistry, and immunofluorescence techniques were used to study the histochemical characteristics of the submandibular gland and the localisation and distribution characteristics of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR). HE results showed that the submandibular gland of Bactrian camels was composed of mixed serous and mucinous acini glands. The submandibular striated duct was highly developed and connected with intercalated ducts with larger diameter. Intercalated ducts are shorter and directly connected to acini. In AB-PAS staining, it was observed that the inner wall of striated tube was strongly positive for AB staining. The distribution of the reticular fibres around the follicles and ducts of the submandibular gland is distinct, with collagen fibres distributed mainly in the periphery of the ducts and sparse collagen fibres in the periphery of the acini. Immunohistochemistry and fluorescence show that EGF is strongly positive in striated and intercalated ducts, and EGFR is weakly positive in striated and intercalated ducts. Bactrian camel SMGs secrete more acidic mucins, and EGF and EGFR were mainly secreted and play a role in the pipeline system of SMGs.

Histopathological evaluation of renal allograft biopsies: a single center study in Dhaka, Bangladesh

Background: Renal transplantation is gradually increasing in Bangladesh due to introduction of live transplantation procedure in some of the urology centers in Dhaka. Graft dysfunction followed by graft failure is one of the worst complications of renal transplantation and graft biopsy is the gold standard to evaluate the cause of failure in addition to clinical parameters. This study was designed to evaluate the causes of graft dysfunction according to Banff classification and correlation with clinical and laboratory parameters. Methods: All the renal graft biopsy samples received at Armed Forces Institute of Pathology during the period from July 2020 to June 2022 were included in the study. Standard histological procedure for renal biopsy including special stains (PAS, Masson Trichrom, Silver) and DIF (IgG, IgA, IgM, C3, C1q, Kappa, Lambda) were applied for all the cases. Immunohistochemistry for C4d and CD3 were also performed for each case. Polyoma virus marker could not be evaluated due to unavailability. BANFF classification was done with the available findings. Results: Total 23 cases were included in this study. All the cases were from live related donors. Mean age of the patients was 34.39 years with male: female ratio 2.28. Time of kidney biopsy from renal transplantation varied from 7 days to 130 months with the average 27.66 months. Graft dysfunction was the indication of the biopsy with average serum creatinine 4.23 mg/dl (range 1.15 to 12.4 mg/dl). Ten (43.48%) of the patients had proteinuria ranging from 1.5 gm to 3 gm/24 hours and 7 (30.43%) patients had haematuria. Among all the cases, 10 (43.48%) came out as Banff category 2 (antibody mediated rejection, ABMR) among them 9 was acute ABMR and one was chronic ABMR. The next common Banff category was Banff 6 (6, 26.09%), which includes IgA nephropathy (2), MPGN (1), CNI toxicity (1), crystal nephropathy (1) and RCN (1). Three (13.04%) were diagnosed as Banff-4 (T cell mediated rejection, TCMR), one (4.34%) was Banff-3 (borderline) and one (4.34%) was Banff-5 (IFTA). Mixed category was observed in 2 cases (Banff-2 + Banff-6). None of the case was diagnosed as Banff-1. Mean age of ABMR was 34.92 years, average duration since transplantation was 20.93 months and mean serum creatinine level was 3.67 mg/dl. Mean age of patients having TCMR was 38.33 years, average duration from transplantation was 59.33 months and mean serum creatinine level 4.71 mg/dl. CNI toxicity was found in a female of 16 years after 10 days of transplantation. One 55 years diabetic male developed graft dysfunction due to crystal nephropathy. One 28-year-old male developed anuria after 7 days of transplantation and diagnosed as post transplant RCN. A 45-year-old male had graft dysfunction after 5 years of transplantation with very high serum creatinine level (12.4 mg/dl) diagnosed as IFTA. Conclusion: Acute ABMR was found to be the prime cause of graft rejection in this study which occured mostly within 2 years of renal transplantation. TCMR occured mostly after 3 years of transplantation. Graft dysfunction due to other than rejection covered 30.43% cases. BIRDEM Med J 2025; 15(1): 28-33

P-773. Mycobacterium Tuberculosis Liver Abscess in Kidney Transplant Recipients

Abstract Background Recipients of solid organ transplant (SOT) have higher risk for infections, and the prevalence of mycobacterium tuberculosis liver abscess (MTB-LA) without pulmonary/disseminated MTB is 0.34%. However, there is little research on MTB-LA in SOT recipients. Mycobacterium tuberculosis Liver Abscess Cases Upon extensive literature review, this chart details all published, English-language cases of mycobacterium tuberculosis liver abscess in solid organ transplant recipients. Methods We conducted an extensive literature review of MTB-LA in adult SOT recipients. Results Our review showed 4 cases of MTB-LA in SOT recipients (table below). We detail 1 additional case. A 58-year-old male with ESRD due to type 2 diabetes mellitus, and latent MTB underwent kidney transplantation in March 2023. He completed a 6-month course of isoniazid and vitamin B6 for latent MTB 1 month before transplant. His post-operative course was uncomplicated; he was discharged to follow up with his nephrologist. He later developed norovirus illness with fever, which was conservatively managed. He developed new fevers 3 months post-transplant and CT of the abdomen/pelvis revealed a liver abscess, which was treated with empiric broad spectrum antibiotics, and was not amenable to aspiration. At his 4-month post-transplantation, he complained of fatigue, night sweats, poor appetite, and weight loss requiring hospitalization, wherein an MRI of the abdomen/pelvis identified a 3.6 x 3.2 x 6.2 cm liver abscess. The liver abscess aspirate was positive on acid fast bacilli smear and MTB polymerase chain reaction. He was initiated on antituberculosis therapy with isoniazid, rifabutin, pyrazinamide, and ethambutol. Susceptibilities identified pyrazinamide resistance, and led to substitution with levofloxacin. Labs, imaging and microbiology testing were negative for evidence of pulmonary/disseminated MTB. His donor’s information was reviewed; no obvious risk factors for active MTB were found. The recipient of the mate kidney is doing well without evidence of MTB infection. After 2 months of 4-drug antituberculosis therapy, ethambutol was discontinued. CT scan of the abdomen and pelvis at 4 months post anti-tuberculosus therapy revealed a 3 cm area of residual inflammation at the site of prior MTB-LA, in the setting of resolution of prior symptoms. Conclusion Early imaging and diagnostic aspiration of liver abscess with specific stains, culture and PCR testing can facilitate rapid diagnosis and initiation of antituberculosis therapy. Disclosures All Authors: No reported disclosures

P-2267. Autopsies: Revisiting the Gold Standard

Abstract Background Infections in solid organ transplant (SOT) recipients continue to be a clinical challenge despite modern diagnostics. Autopsies have the potential to identify missed infectious diagnoses thereby informing the practice of transplant infectious diseases. We sought to evaluate the clinical value of autopsies by analyzing pre-and post-mortem infectious diagnoses of deceased SOT recipients. Methods We retrospectively reviewed deceased adult SOT recipients who underwent autopsies at our institution from January 2017 to December 2022. Electronic medical chart review of these recipients was conducted to determine the clinical infectious diagnoses during the hospitalization in which death occurred. Autopsy reports were reviewed for post-mortem pathological findings. Patients who expired near admission without clinical information or did not expire from infection were excluded. Two physicians independently reviewed clinical information and pathological data and applied the Modified Goldman Criteria to categorize clinical and autopsy infectious discrepancies. Results During the study period, 21 autopsies were performed (Table 1). Pre-mortem infectious diagnoses included bloodstream infections (n = 11), pneumonia alone including 1 case of Rhizopus and 1 case of Pneumocystis (n = 7), CMV viremia (n = 2), cholangitis (n = 1), and sepsis of undetermined etiology (n = 2). In no instances did an autopsy exam reveal an infection undiagnosed pre-mortem, and thus there were no diagnostic errors that met Modified Goldman Criteria. No specific histopathological staining was performed in the cases with CMV viremia or suspected Pneumocystis pneumonia. In the case of Rhizopus, no comment regarding evidence of angioinvasion or extent of infection was made in the autopsy report. Conclusion We did not identify any missed infectious diagnoses on post-mortem evaluation that would have impacted management or outcome. These findings emphasize the importance of collaboration between infectious disease specialists and anatomic pathologists to direct histopathologic and microbiologic testing on tissues of clinical interest. Accurate autopsy diagnoses for SOT recipients, who are at risk for opportunistic and emerging infections, can critically advance transplant medicine. Disclosures All Authors: No reported disclosures

Advancing preservation: plastination and deplastination of human osteochondral units for enhanced histological analyses in Education and Forensic Sciences

In the realm of medical education and research, the preservation of anatomical specimens has traditionally relied on formaldehyde-based fixatives, posing challenges such as loss of 3D orientation, unpleasant odor, and tissue alterations during extended storage. A more contemporary approach introduced in the late 20th century is plastination, which replaces water and fat with durable polymers, providing odorless and stable specimens for ultra-long-term storage. Despite the success of plastination, its impact on subsequent histopathological studies, particularly regarding special stains and immunohistochemistry (IHC), remains largely unexplored. This study delves into assessing the feasibility of staining deplastinated osteochondral units (OCU). Employing a comprehensive multi-step methodology involving fixation, decalcification, plastination, deplastination, paraffin embedding, and various staining protocols, the study meticulously evaluates tissue integrity and staining outcomes using human OCU. Significantly, the plastinated and deplastinated OCUs exhibit well-preserved tissue morphology in Hematoxylin and Eosin staining, successful glycosaminoglycan staining with Safranin O, and effective visualization of collagen types II and X through IHC analysis. A noteworthy observation is the potential to stain plastinated bone-containing specimens after deplastination, addressing the drawbacks of long-term tissue preservation using formalin. This innovation allows subsequent staining as needed, and the direct handling of plastinated specimens enhances three-dimensional visualization, rendering them valuable tools in forensic examinations. These findings open promising avenues for refining methodologies in medical education and forensic settings. The establishment of reliable staining and deplastination protocols holds the potential to significantly improve result accuracy and reproducibility, ultimately expanding applications in these critical fields.

Solitary Rectal Ulcer Syndrome - A Rare Entity in the Pediatric Population.

To study and correlate the clinicopathological findings of Solitary Rectal Ulcer Syndrome (SRUS) in 10 pediatric patients. This study is a retrospective study of patients from January 2017 to June 2024. The clinical records were reviewed for details of the clinical presentation, colonoscopic findings, associated local and systemic diseases, and other investigations. The mean age of presentation was 10±1 years, and the youngest child was 6 years old. The most common clinical presentation was rectal bleeding and a single ulcer on endoscopy. Histological findings included crypt distortion, crypt branching, and fibromuscular obliteration of the lamina propria. Immunohistochemistry (IHC) for Smooth Muscle Actin (SMA) and special staining with Masson Trichrome (MT) were used to highlight fibromuscular areas whenever in doubt. The pathogenesis of SRUS is not well understood. It may be associated with chronic mucosal and hypoperfusion-induced ischemic injury to the rectal mucosa due to trauma or increased rectal pressure during straining. Solitary rectal ulcer is a misnomer, as the patient may present with multiple or no ulcers. Endoscopy and histopathology help to diagnose SRUS. Timely and correct diagnosis reduces the morbidity associated with this entity.

IForensic, multicentric validation of digital whole slide images (WSI) in forensic histopathology setting according to the College of American Pathologists guidelines.

Pathology has benefited from the rapid progress of image-digitizing technology during the last decade. However, the application of digital whole slide images (WSI) in forensic pathology still needs to be improved. WSI validation is crucial to ensure diagnostic performance, at least equivalent to glass slides and light microscopy. The College of American Pathologists Pathology and Laboratory Quality Center recently updated internal digital pathology system validation recommendations. Following these guidelines, this pilot study aimed to validate the performance of a digital approach for forensic histopathological diagnosis. Six independent skilled forensic pathologists from different forensic medicine institutes evaluated 100 glass slides of forensic interest (80 stained with standard hematoxylin and eosin, 20 with special staining), including different organs and tissues, with light microscopy (Olympus BX51, Tokyo, Japan). Glass slides were scanned using the AperioGT 450 DX Digital Slides Scanner (Leica Biosystems, Nussloch, Germany). After two wash-out weeks, forensic pathologists evaluated WSIs in front of a widescreen using computer devices with dedicated software (O3 viewer, O3 Enterprise, Zucchetti, Trieste, Italy). Side-by-side comparisons between diagnoses performed on tissue glass slides versus WSIs were above the threshold stated in the validation guidelines (mean concordance of 97.8%). CSUQ Version 3 questionnaire showed high satisfaction for all pathologists (mean result: 6.6/7). Our institutional digital forensic pathology system has been validated for practical casework application. This approach opens new scenarios in practical forensic casework investigations, such as sharing live histological ex-glass slides online, as well as educational and research perspectives, with improving impacts on the whole daily workflow.

A novel small-molecule fluorescent probe caused by minimal structural modifications for specific staining of the cell nuclear membrane.

The nuclear membrane is a double-layered structure that physically protects the cell's DNA from the chemical reactions occurring in other parts of the cell. In this study, we present the first brand-new small-molecule fluorescent probe that selectively stains the nuclear membrane, allowing for the visualization of nuclear morphology without interfering with the DNA's activity.

Robust differentiation and potent immunomodulation of human mesenchymal stromal cells cultured with a xeno-free GMP protein supplement.

Human mesenchymal stromal cells (hMSC) are multipotent adult cells commonly used in regenerative medicine as advanced therapy medicinal products. The expansion of these cells in xeno-free supplements is highly encouraged by regulatory agencies due to safety concerns. However, the number of supplements with robust performance and consistency for hMSC expansion are limited. Here, we evaluate a xeno-free human plasma-derived protein supplement (Plastem, Grifols) for the expansion and functional evaluation of hMSCs. hMSC from bone marrow, adipose tissue and umbilical cord were obtained from two suppliers and cultured in Dulbecco's modified Eagle's medium (DMEM/F-12) supplemented with fetal bovine serum 10% (FBS), human platelet lysate 5% (hPL) or Plastem 10%+ hPL0.5%. Cell proliferation was evaluated after culturing hMSC for 13 days with trypan blue exclusion. hMSC immunophenotype was assessed by flow cytometry of surface markers expression. Multipotentiality assay determined the ability of hMSC to differentiate into osteogenic, chondrogenic and adipogenic lineages after 21 days, by using specific staining. Immunomodulatory properties of hMSC were analyzed by measuring suppression of human peripheral blood mononuclear cell (PBMC) proliferation in co-culture with hMSC. Plastem 10% + hPL 0.5% supported robust and sustained hMSC growth with a similar efficiency to the reference supplement FBS 10%. hMSC cultured with the xeno-free supplement presented a similar morphology comparable to FBS-supplemented cells and maintained typical expression of markers: positive (>95%) for CD90, CD73 and CD105; and negative (<5%) for CD45, CD14, CD19, CD34 and HLA-DR. Likewise, hMSC showed potent, in vitro differentiation potential into osteogenic, chondrogenic and adipogenic lineages, outperforming the results obtained with traditional reference supplements in several instances. They retained their immunomodulatory properties, inhibiting the proliferation of phytohemagglutinin (PHA)-stimulated PBMCs with a notable enhancement of the immunomodulatory capacity of hMSCs compared to conventional reference supplements. Plastem allowed hMSC expansion while preserving phenotype and showed remarkable differentiation and immunomodulatory properties, supporting its use for cell therapy manufacturing processes as a robust, xeno-free alternative to FBS and hPL. Moreover, Plastem can be manufactured at an industrial level, making it a scalable solution for widespread application.

Antitumor activity of edible fishes (Channa striata and Anabas testudineus) and gastropods (Helix aspersa and Pila virens) rudimentary mucus against HT-29 cell line and its biochemical properties

BackgroundThe mucus from fish and gastropods contains a wide range of bioactive molecules with biomedical properties. The fish and gastropods were collected from Oragadam lake, Kanchipuram district, Tamil Nadu, India. In this study, we wanted to examine the anticancer potential of fish and gastropods mucus. The biochemical components of the crude mucus were screened.ResultsThe biochemical analysis showed that the mucus of Anabas testudineus and Pila virens contained a high level of carbohydrates (2.8 and 1.5 mg/ml), the mucus of Channa striata contained a high level of lipids (0.9 mg/ml), and the mucus of Helix aspersa contained a high level of protein (1.3 mg/ml). The results showed morphological variations in the HT-29 cells upon treatment with crude mucus. Upon 24 h of gestation, the frozen cells began to shrink and seem round in shape. Using the MTT assay, the mucus crude extract was evaluated for its anticancer properties against the human colon cancer cell line (HT 29). The inhibitory concentration (IC50) was determined at 100 µg/ml after 24 h. Using specific staining techniques; fluorescent microscopy was utilized to examine the cell morphology and early and late apoptotic stages. Propidium iodide staining showed nuclear damage followed by DNA damage. This showed that the rudimentary mucus could prompt cell death and increased the number of fragments and mucus concentration, respectively.ConclusionThis study showed that the edible or commercially important fish and gastropod mucus have potential anticancer activity against HT-29 cancer cells.

Pigmented fungus as a cause of chronic otitis externa: A rare case report

Abstract A sporadic infection by a pigmented fungus called chromoblastomycosis is seen in tropical and subtropical climates. It can affect lower extremities most commonly followed by upper extremities. Here, we report an unusual case of chromoblastomycosis causing otitis media in a young female. The ear is an uncommon site of involvement. She presented to the ear, nose, and throat outpatient department with a complaint of left earache for 1 week. On ear examination, the external auditory canal was occluded by debris. Debridement was done from the lesion and was sent for histopathological examination which revealed granulation tissue and fungal spores. Special stains were used to identify the fungus and the patient was treated with antifungals. We report this case to conclude that chromoblastomycosis though rare should be considered as one of the etiologies for otitis externa.

Amorphous Extracellular Eosinophilic Material – The Diagnostic Challenge in Histopathology

Abstract Amyloidosis encompasses a diverse group of conditions characterized by the extracellular accumulation of misfolded, insoluble proteinaceous material with a cross-beta-pleated sheet structure, leading to organ damage. Due to its varied origins and manifestations, different diagnostic tools are required for accurate diagnosis. A definitive diagnosis is achieved through biopsy, revealing amyloid deposits in the affected tissue. When stained with hematoxylin and eosin, amyloid material appears as amorphous eosinophilic acellular deposits. These morphological features are shared with other substances such as collagen, fibrin, plasma, hyaline globules, hyalinization, and necrosis, posing a diagnostic challenge for pathologists. However, morphology, surrounding tissue morphology, and special stains can differentiate between amyloid and amyloid-like material. This case series of six cases highlights the appropriate staining techniques for differentiating amyloid from amyloid-like material in histopathology.

Clinico-hematological and Cytogenetic Study of Myeloid Neoplasms: A cross-sectional Study from South India

ABSTRACT Background: Myeloid neoplasms are clonal diseases arising in hematopoietic stem or progenitor cells consisting of myeloproliferative neoplasm (MPN), myelodysplastic syndrome (MDS), and acute myeloid leukemia (AML). Aim: To re-classify the myeloid neoplasm as per the World Health Organization (WHO)-5 classification and to study the frequency of occurrence and clinical, hematological, and cytogenetic profile of myeloid neoplasms. Settings and Design: A cross-sectional study was conducted for a period of 1 and a 1/2 years from January 2019 to June 2020. Materials and Methods: All the cases newly diagnosed as myeloid neoplasms during this period were included in the study. Clinical features, and hematological and cytogenetic findings were compiled. Statistical Analysis: For categorical data, the number and percentage were used. The Chi-square (χ2) test was used for association between two categorical variables. If the P value was &lt; 0.05, then the results were considered to be statistically significant. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software v. 23 (IBM Statistics, Chicago, USA) and Microsoft Office 2007. Results and Conclusion: A total of 51 cases were observed during the study period. The cases ranged from 14 to 74 years with maximum cases occurring between 51 and 60 years with a male-to-female (M: F) ratio of 1:1.25. Among the 51 cases of myeloid neoplasms, 28 (55%) cases of MPN, 14 (27%) cases of AML, five (10%) cases of MDS, and four (8%) cases of MPN/MDS were observed in their decreasing frequency. The most common symptoms were constitutional symptoms, such as generalized weakness, easy fatigability, and fever. Bone marrow study played a major role in diagnosis. The cytogenetic study complemented the diagnosis. A high clinical suspicion along with a good morphological diagnosis using peripheral smear, bone marrow aspiration, and biopsy supplemented by special stains and molecular studies will enable early and efficient diagnosis of myeloid neoplasms.

Apolipoprotein E3 and E4 isoforms exhibit differing effects in countering endotoxins.

Apolipoprotein E (APOE) is distributed across various human tissues and plays a crucial role in lipid metabolism. Recent investigations have uncovered an additional facet of APOE's functionality, revealing its role in host defense against bacterial infections. To assess the antibacterial attributes of APOE3 and APOE4, we conducted antibacterial assays using P. aeruginosa and E. coli. Exploring the interaction between APOE isoforms and lipopolysaccharides (LPS) from E. coli, we conducted several experiments, including gel shift assays, circular dichroism, and fluorescence spectroscopy. Furthermore, the interaction between APOE isoforms and LPS was further substantiated through atomic resolution molecular dynamics (MD) simulations. The presence of LPS induced the aggregation of APOE isoforms, a phenomenon confirmed through specific amyloid staining, as well as fluorescence and electron microscopy. The scavenging effects of APOE3/4 isoforms were studied through both in vitro and in vivo experiments. In summary, our study established that APOE isoforms exhibit binding to LPS, with a more pronounced affinity and complex formation observed for APOE4 compared to APOE3. Furthermore, our data suggest that APOE isoforms neutralize LPS through aggregation, leading to a reduction of local inflammation in experimental animal models. Additionally, both isoforms demonstrated inhibitory effects on the growth of P. aeruginosa and E. coli. These findings provide new insights into the multifunctionality of APOE in the human body, particularly its role in innate immunity during bacterial infections.

Haemolymphatic tissues of captive boa constrictor (Boa constrictor): Morphological features in healthy individuals and with boid inclusion body disease.

Knowledge on the structure and composition of the haematopoietic tissue (HT) is essential to understand the basic immune functions of the immune system in any species. For reptiles, it is extremely limited, hence we undertook an in-depth in situ investigation of the HT (bone marrow, thymus, spleen, lymphatic tissue of the alimentary tract) in the common boa (Boa constrictor). We also assessed age- and disease-related changes, with a special focus on Boid Inclusion Body Disease, a highly relevant reptarenavirus-associated disease in boid snakes. The HT was subjected to gross, histological and ultrastructural examination, including special stains to highlight collagen and reticulin fibers and iron, immunohistochemistry, in situ hybridization and morphometric analyses. In general, the HT was dominated by T cells and lacked a clear structural organization, such as follicle formation. BIBD was associated with significantly higher cellularity and a granulomatous response in the spleen, and the presence of virus-infected haematopoietic cells in the bone marrow, suggesting the latter as a persistent source of viremia.

Abdominal Actinomycosis Mimicking Malignancy: A Case Report

Abstract Actinomycosis is an uncommon chronic granulomatous disease caused by filamentous, gram-positive anaerobic bacteria. Actinomyces Israeli is the major human pathogen. They are commensal inhabitants of the oral cavity and intestinal tract but acquire invasion of breached or necrotic tissue. We report a 34-year-old female with intra-abdominal actinomycosis with extensive involvement of abdomen mimicking malignancy. She presented with abdominal pain and mass post laparoscopic cholecystectomy and underwent multiple biopsies which were inconclusive and was treated with antimicrobials with no relief. She was referred to our center suspecting malignancy. Biopsy was repeated and histopathology with special stains revealed actinomycosis. She was treated with intravenous crystalline penicillin of 6 million units thrice daily as an inpatient for a week. She was discharged on oral amoxicillin 1 g twice daily. The total antibiotic duration was 12 months since she had extensive disease. She was on regular follow-up and her lesions gradually regressed.

P53 and Ki-67 combined with periodic acid-Schiff staining for the diagnosis of early stage esophageal squamous cell carcinoma lesions in biopsy specimens.

Esophageal cancer is highly prevalent in China, predominantly represented by squamous cell carcinoma. This retrospective study sought to evaluate the diagnostic efficacy of four staining protocols in identifying early stage esophageal squamous cell carcinoma (ESCC). A consecutive series of ninety biopsy samples of esophageal mucosa, collected retrospectively from March 2016 to December 2019, were obtained at Beijing Chao-Yang Hospital, a tertiary care facility in Beijing, China. These samples were categorized into four groups: non-neoplastic squamous lesions (Non-NSL), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and early stage ESCC. Baseline, molecular analyses (p53 by immunohistochemistry and Ki-67 by immunohistochemistry), and staining analyses (hematoxylin & eosin (HE) and periodic acid-Schiff (PAS) were conducted across the categories. The staining protocols included HE, HE + p53 + Ki-67, HE + p53 + Ki-67 + PAS, and HE + p53/PAS + Ki-67/PAS. Patients with HGD and ESCC were significantly older and had larger lesions. Elevated p53 and Ki-67 mutation rates were observed in HGD and ESCC, while increased PAS positivity was noted in RE and LGD. The p53, Ki-67, and PAS staining results showed mostly no correlation among the four groups. Abnormal Ki-67 basal layer distribution pattern correlated with histological grades, with higher proportions in HGD and ESCC. HE + p53 + Ki-67 + PAS and HE + p53/PAS + Ki-67/PAS demonstrated complete consistency with the reference standard, with weighted κ values of 1. HE + p53 + Ki-67 + PAS and HE + p53/PAS + Ki-67/PAS protocols exhibited 100% accuracy, sensitivity, and specificity for diagnosing ESCC or ESCC combined with HGD, outperforming the other protocols. Incorporating specific staining protocols, particularly HE + p53 + Ki-67 + PAS and HE + p53/PAS + Ki-67/PAS, enhances the diagnostic accuracy for early stage ESCC, showing promise in advancing the pathology diagnostic pathway.

Widespread Distribution of α-Synuclein Oligomers in LRRK2-related Parkinson's Disease.

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial and sporadic Parkinson's disease (PD). While the clinical features of LRRK2-PD patients resemble those of typical PD, there are significant differences in the pathological findings. The pathological hallmark of definite PD is the presence of α-synuclein (αSYN)-positive Lewy-related pathology; however, approximately half of LRRK2-PD cases do not have Lewy-related pathology. Lewy-related pathology is a late-stage αSYN aggregation that can be visualized with hematoxylin and eosin stains or conventional immunohistochemistry (IHC). Increasing evidence has indicated that αSYN oligomers, which represent the early-stage of αSYN aggregation, may have neurotoxicity. Visualization of αSYN oligomers requires specialized staining techniques, such as αSYN-proximity ligation assay (PLA). The distribution and severity of αSYN oligomers in the human brain of LRRK2-PD patients remain unknown. In this study, we performed phosphorylated αSYN-IHC and αSYN-PLA staining on postmortem brain sections of patients with three pathogenic LRRK2 mutants: p.G2019S (n=5), p.I2020T (n=5), and p.R1441C (n=4). The severity of Lewy-related pathology and αSYN oligomers were assessed semi-quantitatively in the brainstem, limbic lobe, basal ganglia, and cerebral cortex. αSYN oligomers were detected in LRRK2-PD cases even in cases without Lewy-related pathology; a negative correlation was observed between Lewy-related pathology and αSYN oligomers (r=-0.26 [-0.39, -0.12]; P<0.0001). Our findings suggest that αSYN oligomers may represent a common pathological feature of LRRK2-PD. Notably, patients harboring p.G2019S and p.I2020T had significantly higher levels of αSYN oligomers in those without Lewy-related pathology compared to those with Lewy-related pathology. These cases also had a trend toward shorter disease duration. These results imply that in LRRK2-PD, αSYN oligomers may initially accumulate in the brain but do not progress to form Lewy-related pathology. The present study suggests that targeting αSYN oligomers may be a therapeutic strategy for LRRK2-PD even if there is no Lewy-related pathology.