The crosstalk between gut barrier impairment, mitochondrial dysfunction, and microbiota alterations in people living with HIV.

Functional and structural damage of the intestinal mucosal barrier significantly contribute to translocation of gut microbial products into the bloodstream and are largely involved in HIV-1 associated chronic immune activation. This microbial translocation is largely due to a progressive exhaustion of intestinal macrophage phagocytic function, which leads to extracellular accumulation of microbial derived components and results in HIV-1 disease progression. This study aims to better understand whether the modulation of gut microbiota promotes an intestinal immune restoration in people living with HIV (PLWH). Long-term virologically suppressed PLWH underwent blood, colonic, and fecal sampling before (T0) and after 6 months (T6) of oral bacteriotherapy. Age- and gender-matched uninfected controls (UC) were also included. 16S rRNA gene sequencing was applied to all participants' fecal microbiota. Apoptosis machinery, mitochondria, and apical junctional complex (AJC) morphology and physiological functions were analyzed in gut biopsies. At T0, PLWH showed a different pattern of gut microbial flora composition, lower levels of occludin (p = 0.002) and zonulin (p = 0.01), higher claudin-2 levels (p = 0.002), a reduction of mitochondria number (p = 0.002), and diameter (p = 0.002), as well as increased levels of lipopolysaccharide (LPS) (p = 0.018) and cCK18 (p = 0.011), compared to UC. At T6, an increase in size (p = 0.005) and number (p = 0.008) of mitochondria, as well as amelioration in AJC structures (p < 0.0001) were observed. Restoration of bacterial richness (Simpson index) and biodiversity (Shannon index) was observed in all PLWH receiving oral bacteriotherapy (p < 0.05). Increased mitochondria size (p = 0.005) and number (p = 0.008) and amelioration of AJC structure (p < 0.0001) were found at T6 compared to T0. Moreover, increased occludin and zonulin concentration were observed in PLWH intestinal tracts and decreased levels of claudin-2, LPS, and cCK18 were found after oral bacteriotherapy (T0 vs. T6, p < 0.05 for all these measures). Oral bacteriotherapy supplementation might restore the balance of intestinal flora and support the structural and functional recovery of the gut mucosa in antiretroviral therapy treated PLWH.

Zebrafish ambra1b knockout reveals a novel role for Ambra1 in primordial germ cells survival, sex differentiation and reproduction.

BACKGROUND: AMBRA1 is an intrinsically disordered protein, working as a scaffold molecule to coordinate, by protein-protein interaction, many cellular processes, including autophagy, mitophagy, apoptosis and cell cycle progression. The zebrafish genome contains two ambra1 paralogous genes (a and b), both involved in development and expressed at high levels in the gonads. Characterization of the zebrafish paralogous genes mutant lines generated by CRISPR/Cas9 approach showed that ambra1b knockout leads to an all-male population. RESULTS: We demonstrated that the silencing of the ambra1b gene determines a reduction of primordial germ cells (PGCs), a condition that, in the zebrafish, leads to the development of all-male progeny. PGC reduction was confirmed by knockdown experiments and rescued by injection of ambra1b and human AMBRA1 mRNAs, but not ambra1a mRNA. Moreover, PGC loss was not rescued by injection with human AMBRA1 mRNA mutated in the CUL4-DDB1 binding region, thus suggesting that interaction with this complex is involved in PGC protection from loss. Results from zebrafish embryos injected with murine Stat3 mRNA and stat3 morpholino suggest that Ambra1b could indirectly regulate this protein through CUL4-DDB1 interaction. According to this, Ambra1+/- mice showed a reduced Stat3 expression in the ovary together with a low number of antral follicles and an increase of atretic follicles, indicating a function of Ambra1 in the ovary of mammals as well. Moreover, in agreement with the high expression of these genes in the testis and ovary, we found significant impairment of the reproductive process and pathological alterations, including tumors, mainly limited to the gonads. CONCLUSIONS: By exploiting ambra1a and ambra1b knockout zebrafish lines, we prove the sub-functionalization between the two paralogous zebrafish genes and uncover a novel function of Ambra1 in the protection from excessive PGC loss, which seems to require binding with the CUL4-DDB1 complex. Both genes seem to play a role in the regulation of reproductive physiology.

Caudal peduncle mineralized lesion resembling calcinosis circumscripta in a wels catfish Silurus glanis.

This report presents an intriguing case of a mineralized lesion resembling calcinosis circumscripta observed in the caudal peduncle of a wels catfish, housed in a public aquarium in northern Italy. The investigation encompasses a comprehensive analysis of various aspects, including clinical presentation, diagnostic imaging, as well as gross and microscopic pathology, and immunohistochemistry. Histopathology, in particular, highlighted a severe focally extensive granulomatous reaction, confirmed by dense histiocytic inflammatory infiltrates and the massive presence of multinucleated foreign body type giant cells localized around lakes and aggregates of mineralized material. Moreover, the usefulness and limitations of immunohistochemistry and special stains in characterizing fish tissues and cell types are highlighted. Although reported in elasmobranchs and sturgeons, to our knowledge, this is the first description of calcinosis circumscripta in teleost fish and it offers valuable insights into the understanding of similar pathologies in aquatic organisms.

Nodular gill disease in Northeastern Italy: An investigation on the prevalence of the disease and the risks of introduction in rainbow trout farms.

Nodular Gill Disease (NGD) is an emerging pathogenic condition that causes gill damage and mainly affects farmed freshwater fish, rainbow trout (Oncorhynchus mykiss) in particular, and this inevitably generates noticeable economic losses for the industry. The present study aimed to assess the prevalence of NGD in the Autonomous Province of Trento, a highly productive area located in Northeastern Italy, traditionally suited to rainbow trout production, and to identify possible risk factors for the introduction of this disease in trout farms. The necessary data were obtained through a questionnaire and the collection of fish samples. According to the data analysis, 42% of the investigated farms tested positive for NGD. The two possible risk factors identified for its introduction in farms are the presence of other diseases in the same farm (OR = 17.5; 95% CI = 2.7; 111.5) and having farms located 5 km upstream (OR = 24.8; 95% CI = 2.9; 211.1). These results highlight (i) a possible impairment of the immune system caused by other diseases as a predisposing factor to the manifestation of the pathology and (ii) the role of water in spreading pathogens.

Cutaneous angiomatosis-like presentation in koi carp (Cyprinus carpio koi): Clinical-pathological investigations.

The skin represents an indicator of an animal's health status. Causes of cutaneous diseases in fish most often trace back to biological agents. However, fish skin diseases can also arise from a complex interaction of infectious and non-infectious causes, making it more difficult to identify a specific aetiology. In the period between April and September of the years 2019-2022, four koi carp (Cyprinus carpio koi) from two European countries presented with multifocal, irregularly round, few mm to 1 cm, variably raised cutaneous reddened areas. The fish displayed good general condition. Cutaneous samples, investigated by microbiological and molecular methods and microscopy, did not indicate a primary pathogenic agent. Gross and histological findings of the cutaneous biopsies were consistent with a multifocal/reactive process centred on dermal vessels. The histological features were reminiscent of angiomatosis, a benign proliferative condition affecting the dermal vessels of mammals, including human patients. The clinical-pathological presentation and the dermatologic condition that affected the koi carp are discussed and compared with the veterinary and human literature.

Homozygous CADPS2 Mutations Cause Neurodegenerative Disease with Lewy Body-like Pathology in Parrots.

BACKGROUND: Several genetic models that recapitulate neurodegenerative features of Parkinson's disease (PD) exist, which have been largely based on genes discovered in monogenic PD families. However, spontaneous genetic mutations have not been linked to the pathological hallmarks of PD in non-human vertebrates. OBJECTIVE: To describe the genetic and pathological findings of three Yellow-crowned parrot (Amazona ochrocepahala) siblings with a severe and rapidly progressive neurological phenotype. METHODS: The phenotype of the three parrots included severe ataxia, rigidity, and tremor, while their parents were phenotypically normal. Tests to identify avian viral infections and brain imaging studies were all negative. Due to their severe impairment, they were all euthanized at age 3 months and their brains underwent neuropathological examination and proteasome activity assays. Whole genome sequencing (WGS) was performed on the three affected parrots and their parents. RESULTS: The brains of affected parrots exhibited neuronal loss, spongiosis, and widespread Lewy body-like inclusions in many regions including the midbrain, basal ganglia, and neocortex. Proteasome activity was significantly reduced in these animals compared to a control (P < 0.05). WGS identified a single homozygous missense mutation (p.V559L) in a highly conserved amino acid within the pleckstrin homology (PH) domain of the calcium-dependent secretion activator 2 (CADPS2) gene. CONCLUSIONS: Our data suggest that a homozygous mutation in the CADPS2 gene causes a severe neurodegenerative phenotype with Lewy body-like pathology in parrots. Although CADPS2 variants have not been reported to cause PD, further investigation of the gene might provide important insights into the pathophysiology of Lewy body disorders. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Pulmonary bleeding in racehorses: A gross, histologic, and ultrastructural comparison of exercise-induced pulmonary hemorrhage and exercise-associated fatal pulmonary hemorrhage.

Exercise-induced pulmonary hemorrhage (EIPH) is a common condition of Thoroughbred racehorses that is usually responsible for reduced performance, while exercise-associated fatal pulmonary hemorrhage (EAFPH) is characterized by severe pulmonary bleeding of unknown pathogenesis resulting in sudden death during strenuous exercise. The aim of the study was to characterize and compare anamnestic data together with pulmonary gross, histologic, and ultrastructural findings in racehorses with EIPH (n = 10), EAFPH (n = 10), and control horses (n = 5). No differences in anamnesis were identified between the 3 groups. Grossly cranial lobe reddening and edema scores were significantly more prevalent and severe in the EAFPH group compared with the EIPH and control groups. Histologically, hemorrhage scores were higher in the EAFPH group, while hemosiderophages, iron encrustations of collagen and elastin fibers, and vascular remodeling scores were significantly higher in EIPH group compared with the EAFPH and control groups. In all groups, caudal lung locations exhibited a significantly higher score for vascular remodeling, hemosiderophage accumulation, iron encrustation, and type II pneumocyte hyperplasia when compared with cranial, dorsal, and ventral locations. Ultrastructural analysis of perivascular collagen showed fibrils with significantly larger diameters in the EAFPH group compared with the EIPH group but not compared with the control group. This study demonstrates that lungs of horses that experienced EAFPH show significantly less vascular remodeling and other long-term pulmonary abnormalities that characterize horses with EIPH.

Severe gastroenteropathy associated with Clostridium perfringens isolation in starving juvenile sturgeons.

In November 2020 a mortality episode (30%) in juvenile Siberian and Russian sturgeons (Acipenser baerii, Brandt, and A. gueldenstaedtii, Brandt & Ratzeburg) and GUBA hybrid sturgeons (A. gueldenstaedtii × A. baerii) occurred in a hatchery in Northern Italy, associated with severe coelomic distension and abnormal reverse surface swimming. The fish were reared in concrete tanks supplied by well water, fed at 0.4% of body weight (b.w.) per day. Thirty sturgeon specimens were collected for necropsy, histological, bacteriological and virological examination. Macroscopic findings included diffuse and severe bloating of gastrointestinal tracts due to foamy contents with thinning and stretching of the gastrointestinal walls. Histological analysis revealed variable degrees of sloughing and necrosis of the intestinal epithelium, and the presence of bacterial aggregates. Anaerobic Gram-positive bacteria were investigated, and Clostridium perfringens was isolated from the gut. Specific PCRs identified the toxinotype A and the ß2 toxin gene. The daily feed administration was increased to 1.5% b.w. and after 5 days, the mortality ceased. A new animal cohort from the same groups was examined after 12 weeks, showing neither gut alterations nor isolation of C. perfringens. The imbalance of intestinal microbiota, presumably caused by underfeeding, favoured C. perfringens overgrowth and severe gas formation. The diet increase possibly restored the normal microbiota.

Ultrasound-guided erector spinae plane block in horses: a cadaver study.

OBJECTIVES: To describe dye distribution and spinal nerve involvement after a simulated erector spinae plane (ESP) block performed on fresh equine cadavers. STUDY DESIGN: Experimental cadaver study. ANIMALS: A group of 11 adult equine cadavers. METHODS: The spinal region surrounding the sixteenth thoracic vertebra (Th16) of one cadaver was removed and underwent magnetic resonance imaging. In 10 adult equine cadavers [body weight, 549 ± 58 kg (mean ± standard deviation)], 0.2 mL kg-1 of a 50:1 2% lidocaine/dye solution was injected bilaterally (n = 20 injections) into the fascial plane between the transverse process of Th16 and the erector spinae muscles. An in-plane ultrasound-guided technique with a convex transducer was used to guide injection. Dissection was performed immediately following injection. The craniocaudal and lateral extent of dye distribution was measured (cm) and the number of vertebral bodies involved were counted (n = 20). Abdominal and thoracic cavities as well as the epidural space were also examined for presence of dye (yes/no) (n = 20). Further dissection was performed to evaluate if staining of the dorsal and ventral rami of the spinal nerves and sympathetic chain occurred (n = 14). RESULTS: The thoracolumbar fascia was stained in 17/20 (85%) injections and three injections terminated intramuscularly. Multisegmental staining of the dorsal rami was observed in the 14 injections in which staining was evaluated. Ventral rami staining was observed in 3/14 injections where staining was evaluated. Epidural migration was observed in 4/20 (20%) injections. No evidence of dye was found in the thoracic and abdominal cavities or on the sympathetic chain. CONCLUSIONS AND CLINICAL RELEVANCE: The ESP block may prove beneficial to desensitize structures innervated by the dorsal rami of the thoracic spinal nerves. Further investigation is necessary to evaluate complications caused by epidural contamination.

Spontaneous neoplasia in captive syngnathid species: A retrospective case series (2003-2014) and literature review.

Syngnathidae (seahorses, pipefish and seadragons) are charismatic species commonly kept in commercial aquaria, but published literature on syngnathid diseases is limited and immunohistochemical techniques not routinely employed. A retrospective review of 2,541 syngnathid submissions received between March 2003 and October 2016 identified 18 neoplasms including germ cell tumours, exocrine pancreatic and intestinal carcinomas, chromatophoromas, and single cases of lymphoma, thyroid and renal carcinoma, swim bladder and pituitary adenoma. Big-bellied seahorses accounted for 19% of submissions, but 50% of neoplasms were diagnosed in this species. This study includes the first reported cases of germ cell tumours, chromatophoroma, thyroid carcinoma and pituitary adenoma in Syngnathidae and the first reports of neoplasia in pipefish species. Out of nine commercial antibodies trialled for immunohistochemical characterization of neoplastic tissue, only pan-cytokeratin proved cross-reactive. Electron microscopy was performed in four cases. Tumours should be considered as differential diagnosis in cases with buoyancy issues, debilitated or emaciated animals, and may predispose to secondary infections. This study highlights the value of histopathological disease surveillance for commercial aquarium settings.

Canine Clitoral Carcinoma: A Clinical, Cytologic, Histopathologic, Immunohistochemical, and Ultrastructural Study.

Vaginal and vulvar tumors are uncommon in dogs. Knowledge of canine primary clitoral neoplasia is restricted to a few case reports, and only carcinomas have been reported. Cytologic and histologic features reported in the literature seem to overlap with those of canine apocrine gland anal sac adenocarcinoma (AGASA). Clinical features also recall those of canine AGASA, such as locoregional metastases and hypercalcemia of malignancy (HM). In this study, 6 cases of primary canine clitoral carcinomas (CCCs), with and without HM, were investigated by means of cytology, histopathology, electron microscopy, and immunohistochemistry for neuroendocrine markers including chromogranin A (CGA), synaptophysin (SYN), neuron-specific enolase (NSE), and S-100. In all 6 tumors, cytologic findings were consistent with malignant epithelial neoplasia of apocrine gland origin. The tumors examined were classified into 3 different histological patterns representing different degrees of differentiation: tubular, solid, and rosette type. Both CGA and SYN were mildly expressed in 2 of 6 tumors, while NSE was consistently expressed in all 6 cases. None of the tumors were S-100 positive. Transmission electron microscopy revealed electron-dense cytoplasmic granules compatible with neuroendocrine granules in all 6 cases. CCCs presented clinicopathologic features resembling AGASAs with neuroendocrine characteristics, and 2 of 6 neoplasms were considered as carcinomas with neuroendocrine differentiation and were positive for 3 neuroendocrine markers. CCCs can often present with HM, and long-term outcome is likely poor. Our study concludes that CCC seems to be a rare tumor, but it might be underestimated because of the overlapping features with AGASA. Further studies should aim to define the true incidence of this disease.

Novel insights on microbiome dynamics during a gill disease outbreak in farmed rainbow trout (Oncorhynchus mykiss).

The generic term "Gill disease" refers to a wide range of disorders that affect the gills and severely impact salmonid aquaculture systems worldwide. In rainbow trout freshwater aquaculture, various etiological agents causing gill diseases have been described, particularly Flavobacterium and Amoeba species, but research studies suggest a more complex and multifactorial aetiology. Here, a cohort of rainbow trout affected by gill disease is monitored both through standard laboratory techniques and 16S rRNA Next-Generation Sequencing (NGS) analysis during a natural disease outbreak and subsequent antibiotic treatment with Oxytetracycline. NGS results show a clear clustering of the samples between pre- and post-treatment based on the microbial community of the gills. Interestingly, the three main pathogenic bacteria species in rainbow trout (Yersinia ruckeri, Flavobacterium psychrophilum, and Flavobacterium branchiophilum) appear to be weak descriptors of the diversity between pre-treatment and post-treatment groups. In this study, the dynamics of the gill microbiome during the outbreak and subsequent treatment are far more complex than previously reported in the literature, and environmental factors seem of the utmost importance in determining gill disease. These findings present a potential novel perspective on the diagnosis and management of gill diseases, showing the limitations of conventional laboratory methodologies in elucidating the complexity of this disease in rainbow trout. To the authors' knowledge, this work is the first to describe the microbiome of rainbow trout gills during a natural outbreak and subsequent antibiotic treatment. The results of this study suggest that NGS can play a critical role in the analysis and comprehension of gill pathology. Using NGS in future research is highly recommended to gain deeper insights into such diseases correlating gill's microbiome with other possible cofactors and establish strong prevention guidelines.

Identification of druggable host dependency factors shared by multiple SARS-CoV-2 variants of concern.

The high mutation rate of SARS-CoV-2 leads to the emergence of multiple variants, some of which are resistant to vaccines and drugs targeting viral elements. Targeting host dependency factors, e.g. cellular proteins required for viral replication, would help prevent the development of resistance. However, it remains unclear whether different SARS-CoV-2 variants induce conserved cellular responses and exploit the same core host factors. To this end, we compared three variants of concern and found that the host transcriptional response was conserved, differing only in kinetics and magnitude. Clustered regularly interspaced short palindromic repeats screening identified host genes required for each variant during infection. Most of the genes were shared by multiple variants. We validated our hits with small molecules and repurposed the US Food and Drug Administration-approved drugs. All the drugs were highly active against all the tested variants, including new variants that emerged during the study (Delta and Omicron). Mechanistically, we identified reactive oxygen species production as a key step in early viral replication. Antioxidants such as N-acetyl cysteine (NAC) were effective against all the variants in both human lung cells and a humanized mouse model. Our study supports the use of available antioxidant drugs, such as NAC, as a general and effective anti-COVID-19 approach.

Persistent marked cerebrospinal fluid eosinophilia in a dog with primary central nervous system histiocytic sarcoma.

A 6-year-old female spayed Jack Russell Terrier was evaluated for episodic seizure-like activity and intermittent obtundation over the previous 3 weeks. Magnetic resonance imaging (MRI) of the brain revealed mild generalized dilation of the ventricular system with periventricular edema. A focal area of mildly increased lepto- and pachymeningeal contrast uptake in the region of the right parietal and occipital lobes was observed. Analysis of cerebrospinal fluid (CSF) revealed marked mixed pleocytosis with 20% eosinophils and no atypical cells or microorganisms. The dog transiently improved with prednisolone for suspected eosinophilic meningoencephalitis/meningoencephalomyelitis of unknown origin (MUO) but worsened over the following 5 months. Brain MRI and CSF sampling were repeated. Additional multifocal lesions were evident in the brainstem and cerebellum. On CSF analysis, the eosinophilic pleocytosis and increased total protein persisted. The clinical signs progressed despite treatment, and the patient was euthanized 6 weeks later. A post-mortem examination was performed. Histopathology and immunohistochemistry revealed a multifocal neoplastic proliferation of cells in the brain, diffusely and strongly positive for ionized calcium-binding adapter molecule (Iba-1) and negative for AE1/AE3 pan-cytokeratin and glial-fibrillar-acid-protein (GFAP) immunostaining, consistent with a diagnosis of histiocytic sarcoma (HS). No other organic lesions were found; therefore, the neoplasm was considered a primary HS of the central nervous system (CNS). This case report stresses the importance of considering primary CNS HS in the differential diagnosis of dogs with marked CSF eosinophilia, even in the absence of atypical cells on cytologic examination.

What Is Your Diagnosis?

In collaboration with the American College of Veterinary Radiology.

Systematic validation and assessment of immunohistochemical markers for central nervous system pathology in cetaceans, with emphasis on auditory pathways.

Cetacean neuropathology is a developing field that aims to assess structural and neurochemical changes involved in neurodegenerative, infectious and traumatic processes, however markers used previously in cetaceans have rarely undergone systematic validation. This is a prerequisite to investigating the potential damage inflicted on the cetacean auditory system by anthropogenic noise. In order to assess apoptotic, neuroinflammatory and structural aberrations on a protein level, the baseline expression of biomarker proteins has to be characterized, implementing a systematic approach to validate the use of anti-human and anti-laboratory animal antibodies in dolphin tissues. This approach was taken to study 12 different antibodies associated with hypoxic-ischemic, inflammatory, plastic and excitatory-inhibitory changes implicated in acoustic trauma within the ventral cochlear nuclei and inferior colliculi of 20 bottlenose dolphins (Tursiops truncatus). Out of the 12 tested antibodies, pro-apoptotic protease factor 1 (Apaf-1), diacylglycerolkinase-ζ (DGK-ζ), B-cell lymphoma related protein 2 (Bcl-2), amyloid-ß peptide (Aß) and neurofilament 200 (NF200) were validated employing Western blot analyses and immunohistochemistry (IHC). The results of the validation process indicate specific patterns of immunoreactivity that are comparable to those reported in other mammals, thus suggesting a key panel of IHC biomarkers of pathological processes in the cetacean brain. As a consequence, the antibodies tested in this study may constitute a valid tool for supporting existing diagnostic methods in neurological diseases. The approach of systematic validation of IHC markers in cetaceans is proposed as a standard practice, in order for results to be transparent, reliable and comparable.

Natural cases of polyarthritis associated with feline calicivirus infection in cats.

The limping syndrome is occasionally reported during acute feline calicivirus (FCV) infections or as consequence of vaccination. In this retrospective study, three clinical cases of lameness in household cats naturally infected by FCV were described and phylogeny of the virus were investigated by analysing the hypervariable E region of the ORF2 viral gene. Cats were diagnosed with polyarthritis and FCV RNA or antigens were detected in symptomatic joints. One cat, euthanized for ethical reasons, underwent a complete post-mortem examination and was subjected to histopathological and immunohistochemical investigations. No phylogenetic subgrouping were evident for the sequenced FCV. Histopathology of the euthanized cat revealed diffuse fibrinous synovitis and osteoarthritis eight months after the onset of lameness and the first detection of FCV RNA, supporting the hypothesis of a persistent infection. FCV was demonstrated by immunohistochemistry in synoviocytes and fibroblasts of the synovial membranes. This study provides new data on the occurrence of polyarthritis in FCV-infected cats, demonstrates by immunohistochemistry the presence of FCV in the synovial membranes of a cat with persistent polyarthritis and supports the absence of correlation between limping syndrome and phylogenetic subgrouping of viruses.