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Neurosyphilis-induced dementia represents a severe manifestation of tertiary syphilis, characterized by cognitive and neuropsychiatric impairments. This condition arises from the progression of syphilis to the central nervous system, where the spirochete causes damage through invasion, chronic inflammation, and neurodegeneration. The pathophysiology involves chronic inflammatory responses, direct bacterial damage, and proteinopathies. Treponema pallidum triggers an inflammatory cascade, resulting in neuronal injury and synaptic dysfunction. Abnormal protein accumulations, including TAR DNA-binding protein 43 (TDP-43) and tau, contribute to neuronal loss and cognitive decline. Seizures, psychiatric symptoms, and motor deficits further complicate the progression of dementia. Diagnosis includes clinical assessment, cerebrospinal fluid analysis, and neuroimaging. Diagnostic tests include CSF-VDRL, FTA-ABS, and neuroimaging techniques such as MRI and PET scans, which help detect structural changes and confirm neurosyphilis. Management of neurosyphilis-induced dementia involves antibiotic therapy and psychotropic medications to address both infectious and symptomatic components. While penicillin remains the cornerstone of treatment, psychotropic agents, including haloperidol, risperidone, quetiapine, and divalproex sodium, can manage psychiatric symptoms. However, careful monitoring is required due to potential side effects and interactions with ongoing treatment. Overall, early diagnosis and comprehensive management are crucial for mitigating the cognitive and neuropsychiatric impairments associated with neurosyphilis-induced dementia.

Antibiotic development is not new to the medical community, but the emergence of antibiotic resistance has become the most serious threat to global health and food security. It results in longer hospital stays, more expensive medical treatments, and greater mortality rates around the world. The basic categories used to describe antibiotic resistance originating from both natural and genetically driven processes are natural, acquired, cross-resistance, multidrug, and pan-drug resistance. Bacterial intrinsic resistance is characterized by continued improvement of resistance mechanisms via cell wall structure and other cellular features. Resistant drug uptake, target site change, efflux pump mechanism, and target site mutation are examples of resistance mechanisms. The presence of resistant bacteria and antibiotic residues in the environment requires urgent global action to combat antimicrobial resistance (AMR). Discovering new antibiotics is not the only prerequisite for dealing with this scenario; continuous national surveillance of antibiotic resistance gene level dissemination is also necessary. This review provides the most up-to-date status of the mechanisms of AMR against several antibiotics on the market and how the resistant bacteria have evolved with diverse mechanisms for their survival. It also discusses the significant clinical consequences and the impact of resistant bacteria exposure on public health. Further, it puts together a global understanding of the prevalence of resistant genes and offers recommendations to stop the further spread with some guidelines.

Objectives: Monkeypox (MPox) is a zoonotic virus in the genus Orthopoxvirus. It is transmitted from animal to human, and between humans. The clinical presentations vary, starting with a prodrome phase to different skin findings and systemic complications. Methods: We present two distinctive cases of MPox co-infected with other viruses (hepatitis C virus [HCV] and HIV) by clinical and histopathological analysis. Results: Surprisingly, the MPox patient with a history of HCV developed different skin pathological characteristics (less severe inflammatory changes than the classic patient with HCV or MPox alone). In contrast, patients living with HIV presenting with MPox had severe inflammatory cutaneous changes and distortion of the skin architecture. Conclusion: Our findings strongly suggest that MPox infections likely occur in the presence of one or more previous other viral infections, and the prior infection with specific microbes determines the severity of MPox infection.

Clostridial myonecrosis, commonly known as gas gangrene (GG), is a rapidly progressing and potentially fatal bacterial infection that primarily affects muscle and soft tissue. In the United States, the incidence of GG is roughly 1000 cases per year, while, in developing countries, the incidence is higher. This condition is most often caused by Clostridium perfringens, a Gram-positive, spore-forming anaerobic bacterium widely distributed in the environment, although other Clostridium species have also been reported to cause GG. The CP genome contains over 200 transport-related genes, including ABC transporters, which facilitate the uptake of sugars, amino acids, nucleotides, and ions from the host environment. There are two main subtypes of GG: traumatic GG, resulting from injuries that introduce Clostridium spores into deep tissue, where anaerobic conditions allow for bacterial growth and toxin production, and spontaneous GG, which is rarer and often occurs in immunocompromised patients. Clostridium species produce various toxins (e.g., alpha, theta, beta) that induce specific downstream signaling changes in cellular pathways, causing apoptosis or severe, fatal immunological conditions. For example, the Clostridium perfringens alpha toxin (CPA) targets the host cell’s plasma membrane, hydrolyzing sphingomyelin and phosphatidylcholine, which triggers necrosis and apoptosis. The clinical manifestations of clostridial myonecrosis vary. Some patients experience the sudden onset of severe pain, swelling, and muscle tenderness, with the infection progressing rapidly to widespread tissue necrosis, systemic toxicity, and, if untreated, death. Other patients present with discharge, pain, and features of cellulitis. The diagnosis of GG primarily involves clinical evaluation, imaging studies such as X-rays, computer tomography (CT) scans, and culture. The treatment of GG involves surgical exploration, broad-spectrum antibiotics, antitoxin, and hyperbaric oxygen therapy, which is considered an adjunctive treatment to inhibit anaerobic bacterial growth and enhance the antibiotic efficacy. Early recognition and prompt, comprehensive treatment are critical to improving the outcomes for patients affected by this severe and life-threatening condition.

The COVID-19 pandemic has been one of the most impactful events in our lifetime, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Multiple SARS-CoV-2 variants were reported globally, and a wide range of symptoms existed. Individuals who contract COVID-19 continue to suffer for a long time, known as long COVID or post-acute sequelae of COVID-19 (PASC). While COVID-19 vaccines were widely deployed, both unvaccinated and vaccinated individuals experienced long-term complications. To date, there are no treatments to eradicate long COVID. We recently conceived a new approach to treat COVID in which a 15-amino-acid synthetic peptide (SPIKENET, SPK) is targeted to the ACE2 receptor binding domain of SARS-CoV-2, which prevents the virus from attaching to the host. We also found that SPK precludes the binding of spike glycoproteins with the receptor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) of a coronavirus, murine hepatitis virus-1 (MHV-1), and with all SARS-CoV-2 variants. Further, SPK reversed the development of severe inflammation, oxidative stress, tissue edema, and animal death post-MHV-1 infection in mice. SPK also protects against multiple organ damage in acute and long-term post-MHV-1 infection. Our findings collectively suggest a potential therapeutic benefit of SPK for treating COVID-19.

The COVID-19 pandemic, which emerged in early 2020, has had a profound and lasting impact on global health, resulting in over 7.0 million deaths and persistent challenges. In addition to acute concerns, there is growing attention being given to the long COVID health consequences for survivors of COVID-19 with documented cases of cardiovascular abnormalities, liver disturbances, lung complications, kidney issues, and noticeable cognitive deficits. Recent studies have investigated the physiological changes in various organs following prolonged exposure to murine hepatitis virus-1 (MHV-1), a coronavirus, in mouse models. One significant finding relates to the effects on the gastrointestinal tract, an area previously understudied regarding the long-lasting effects of COVID-19. This research sheds light on important observations in the intestines during both the acute and the prolonged phases following MHV-1 infection, which parallel specific changes seen in humans after exposure to SARS-CoV-2. Our study investigates the histopathological alterations in the small intestine following MHV-1 infection in murine models, revealing significant changes reminiscent of inflammatory bowel disease (IBD), celiac disease. Notable findings include mucosal inflammation, lymphoid hyperplasia, goblet cell hyperplasia, and immune cell infiltration, mirroring pathological features observed in IBD. Additionally, MHV-1 infection induces villous atrophy, altered epithelial integrity, and inflammatory responses akin to celiac disease and IBD. SPIKENET (SPK) treatment effectively mitigates intestinal damage caused by MHV-1 infection, restoring tissue architecture and ameliorating inflammatory responses. Furthermore, investigation into long COVID reveals intricate inflammatory profiles, highlighting the potential of SPK to modulate intestinal responses and restore tissue homeostasis. Understanding these histopathological alterations provides valuable insights into the pathogenesis of COVID-induced gastrointestinal complications and informs the development of targeted therapeutic strategies.

Abstract Background Epididymitis has several etiologies that can be related to infectious and non-infectious causes, autoimmune conditions, aseptic causes, and even certain pharmaceutical medications (amiodarone and chemotherapeutic agents). Some cases of epididymitis are complicated with pyocele formation that requires emergent surgical intervention to prevent testicular gangrene. This report describes the case of a 66-year-old male who developed severe bilateral epididymitis complicated by bilateral pyocele and ensuing sepsis. Astonishingly, the condition resolved completely without surgical intervention. Case presentation We are presenting a case of a non-sexually active male who developed bilateral severe epididymitis complicated by pyocele that led to the development of septic shock. Further history revealed that the patient was not sexually active with male or female partners and denied any form of trauma. Physical examination demonstrated scrotal swelling and erythema on inspection and severe tenderness on palpation. Digital rectal examination as well as abdominal examinations was unremarkable. Laboratory investigations disclosed severe leukocytosis with a neutrophil predominance (39,000 K/UL, normal range 4500–11,000 K/UL), as well as an elevation of systemic inflammatory markers such as erythrocyte sedimentation rate and C-reactive protein. Urine culture was positive for Escherichia coli. Ultrasound revealed bilateral epididymitis and pyocele. This patient was managed with a course of meropenem, resolving the epididymitis and pyocele without the need of surgical intervention. Conclusions Surgical intervention is considered the standard of care and the approved management for pyocele to avoid further complications such as Fournier’s gangrene. However, this patient was treated solely with antibiotics, and his condition was stabilized without the need of surgical intervention that would result in additional cost and length of stay for the patient. This case raises further questions regarding the potentially better bioavailability of this antibiotic in the scrotum compared to elsewhere in the body and the potential for a non-surgical alternative approach in the management of patients with pyocele and requires further research.

Hepatic encephalopathy (HE) is a major neuropsychological condition that occursas a result of impaired liver function. It is frequently observed in patients with advanced liver disease or cirrhosis. Memory impairment is among the symptoms of HE; the pathophysiologic mechanism for this enervating condition remains unclear. However, it is possible that neuroinflammation may be involved, as recent studies have emphasized such phenomena. Therefore, the aim of the present study is to assess short working memory (SWM) and examine the involvement of microglia in a chronic model of HE. The study was carried out with male Wistar rats that were induced by repeated thioacetamide (TAA) administration (100 mg/kg i.p injection for 10 days). SWM function was assessed through Y-maze, T-Maze, and novel object recognition (NOR) tests, together with an immunofluorescence study of microglia activation within the hippocampal areas. Our data showed impaired SWM in TAA-treated rats that was associated with microglial activation in the three hippocampal regions, and which contributed to cognitive impairment.

Hepatic encephalopathy (HE) is a neurological condition linked to liver failure. Acute HE (Type A) occurs with acute liver failure, while chronic HE (Type C) is tied to cirrhosis and portal hypertension. HE treatments lag due to gaps in understanding its development by gender and age. We studied how sex and age impact HE and its severity with combined liver toxins. Our findings indicate that drug-induced (thioacetamide, TAA) brain edema was more severe in aged males than in young males or young/aged female rats. However, adding alcohol (ethanol, EtOH) worsens TAA’s brain edema in both young and aged females, with females experiencing a more severe effect than males. These patterns also apply to Type A HE induced by azoxymethane (AZO) in mice. Similarly, TAA-induced behavioral deficits in Type C HE were milder in young and aged females than in males. Conversely, EtOH and TAA in young/aged males led to severe brain edema and fatality without noticeable behavioral changes. TAA metabolism was slower in aged males than in young or middle-aged rats. When TAA-treated aged male rats received EtOH, there was a slow and sustained plasma level of thioacetamide sulfoxide (TASO). This suggests that with EtOH, TAA-induced HE is more severe in aged males. TAA metabolism was similar in young, middle-aged, and aged female rats. However, with EtOH, young and aged females experience more severe drug-induced HE as compared to middle-aged adult rats. These findings strongly suggest that gender and age play a role in the severity of HE development and that the presence of one or more liver toxins may aggravate the severity of the disease progression.

The coronavirus disease-19 (COVID-19) pandemic, declared in early 2020, has left an indelible mark on global health, with over 7.0 million deaths and persistent challenges. While the pharmaceutical industry raced to develop vaccines, the emergence of mutant severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) strains continues to pose a significant threat. Beyond the immediate concerns, the long-term health repercussions of COVID-19 survivors are garnering attention, particularly due to documented cases of cardiovascular issues, liver dysfunction, pulmonary complications, kidney impairments, and notable neurocognitive deficits. Recent studies have delved into the pathophysiological changes in various organs following post-acute infection with murine hepatitis virus-1 (MHV-1), a coronavirus, in mice. One aspect that stands out is the impact on the skin, a previously underexplored facet of long-term COVID-19 effects. The research reveals significant cutaneous findings during both the acute and long-term phases post-MHV-1 infection, mirroring certain alterations observed in humans post-SARS-CoV-2 infection. In the acute stages, mice exhibited destruction of the epidermal layer, increased hair follicles, extensive collagen deposition in the dermal layer, and hyperplasticity of sebaceous glands. Moreover, the thinning of the panniculus carnosus and adventitial layer was noted, consistent with human studies. A long-term investigation revealed the absence of hair follicles, destruction of adipose tissues, and further damage to the epidermal layer. Remarkably, treatment with a synthetic peptide, SPIKENET (SPK), designed to prevent Spike glycoprotein-1 binding with host receptors and elicit a potent anti-inflammatory response, showed protection against MHV-1 infection. Precisely, SPK treatment restored hair follicle loss in MHV-1 infection, re-architected the epidermal and dermal layers, and successfully overhauled fatty tissue destruction. These promising findings underscore the potential of SPK as a therapeutic intervention to prevent long-term skin alterations initiated by SARS-CoV-2, providing a glimmer of hope in the battle against the lingering effects of the pandemic.

Abstract The spectrum of presentation of airway foreign body can vary from having mild symptoms to sudden death. Smaller foreign body in distal airways, especially if the patient is unaware of aspiration can result in chronic symptoms mimicking asthma. Clove, has been used traditionally for its medicinal values and commonly used as a cough remedy. In this case series, we report four cases of this unusual airway foreign body which were essentially consumed with an intention to prevent cough, but unfortunately became the reason for their cough.

Purpura fulminans (PF) is a disorder with multifactorial causes that lead to acute localize skin microvasculature thrombosis. PF can be classified as one of the manifestations of disseminated vascular coagulation (DIC). Although, there are three types of PF including hereditary (autosomal dominant) due to mutations in single nucleotide polymorphisms (PROC and PROS1) and serpin family C member 1 (SERPINC1) genes. Idiopathic or acquired type of PF is complex and the pathophysiology is ambiguous, however, low levels of protein C and S were observed. The acute infectious form of PF occurs post-bacterial infection (e.g., Neisseria). The clinical presentation is limited to skin findings or systematic manifestation (shock, disseminated intravascular coagulation, or death). We are presenting two cases of PF sharing similar clinical manifestations developed within 12 h post-operatively with distinct micro-organisms infection. The first patient’s wound culture grew fluffy mold, and the sequencing confirmed a Mucormycosis, Absidia corymbifera species, while the second patient was infected by cutaneous Candida glabrata which led to the development of PF. Our findings suggest that surgery can trigger local immunological responses in susceptible individuals such as concealed protein C and S deficiency or microorganism toxins that initiated the rapidly developing of PF in those patients.

Abstract Background Sleep quality is among the indicators associated with the quality of life of patients with cancer. A multitude of factors may affect patient sleep quality and are considered as associated predictive factors. The aim of this study was to examine the predictors of poor sleep quality in Moroccan women with gynecological cancer after radical surgery. Methods A cross-sectional study was carried out at the Oncology Department of the Ibn Rochd University Hospital, Casablanca (Morocco), on women who had undergone radical surgery for gynecological cancer (n = 100; mean age: 50.94 years). To assess sleep quality, symptoms of depression and anxiety, self-esteem and body image, the following translated and validated Arabic versions of the tools were used: Pittsburgh Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale, Rosenberg’s Self-Esteem Scale and Body Image Scale. To determine predictors of sleep quality, multiple linear and hierarchical regressions were used. Results 78% of participants were considered poor sleepers, most of them exhibited very poor subjective quality (53%), longer sleep onset latency (55%), short period of sleep (42%) and low rate of usual sleep efficiency (47%). 79% of these patients did not use sleep medication and 28% were in poor shape during the day. Waking up in the middle of the night or early in the morning and getting up to use the bathroom were the main reasons for poor sleep quality. Higher PSQI scores were positively correlated with higher scores of anxiety, depression, body image dissatisfaction and with lower self-esteem (p

Signs and symptoms involving multiple organ systems which persist for weeks or months to years after the initial SARS-CoV-2 infection (also known as PASC or long COVID) are common complications of individuals with COVID-19. We recently reported pathophysiological changes in various organs post-acute infection of mice with mouse hepatitis virus-1 (MHV-1, a coronavirus) (7 days) and after long-term post-infection (12 months). One of the organs severely affected in this animal model is the kidney, which correlated well with human studies showing kidney injury post-SARS-CoV-2 infection. Our long-term post-infection pathological observation in kidneys includes the development of edema and inflammation of the renal parenchyma, severe acute tubular necrosis, and infiltration of macrophages and lymphocytes, in addition to changes observed in both acute and long-term post-infection, which include tubular epithelial cell degenerative changes, peritubular vessel congestion, proximal and distal tubular necrosis, hemorrhage in the interstitial tissue, and vacuolation of renal tubules. These findings strongly suggest the possible development of renal fibrosis, in particular in the long-term post-infection. Accordingly, we investigated whether the signaling system that is known to initiate the above-mentioned changes in kidneys in other conditions is also activated in long-term post-MHV-1 infection. We found increased TGF-β1, FGF23, NGAL, IL-18, HIF1-α, TLR2, YKL-40, and B2M mRNA levels in long-term post-MHV-1 infection, but not EGFR, TNFR1, BCL3, and WFDC2. However, only neutrophil gelatinase-associated lipocalin (NGAL) increased in acute infection (7 days). Immunoblot studies showed an elevation in protein levels of HIF1-α, TLR-2, and EGFR in long-term post-MHV-1 infection, while KIM-1 and MMP-7 protein levels are increased in acute infection. Treatment with a synthetic peptide, SPIKENET (SPK), which inhibits spike protein binding, reduced NGAL mRNA in acute infection, and decreased TGF-β1, BCL3 mRNA, EGFR, HIF1-α, and TLR-2 protein levels long-term post-MHV-1 infection. These findings suggest that fibrotic events may initiate early in SARS-CoV-2 infection, leading to pronounced kidney fibrosis in long COVID. Targeting these factors therapeutically may prevent acute or long-COVID-associated kidney complications.

Severe disease from SARS-CoV-2 infection often progresses to multi-organ failure and results in an increased mortality rate amongst these patients. However, underlying mechanisms of SARS- CoV-2-induced multi-organ failure and subsequent death are still largely unknown. Cytokine storm, increased levels of inflammatory mediators, endothelial dysfunction, coagulation abnormalities, and infiltration of inflammatory cells into the organs contribute to the pathogenesis of COVID-19. One potential consequence of immune/inflammatory events is the acute progression of generalized edema, which may lead to death. We, therefore, examined the involvement of water channels in the development of edema in multiple organs and their contribution to organ dysfunction in a Murine Hepatitis Virus-1 (MHV-1) mouse model of COVID-19. Using this model, we recently reported multi-organ pathological abnormalities and animal death similar to that reported in humans with SARS-CoV-2 infection. We now identified an alteration in protein levels of AQPs 1, 4, 5, and 8 and associated oxidative stress, along with various degrees of tissue edema in multiple organs, which correlate well with animal survival post-MHV-1 infection. Furthermore, our newly created drug (a 15 amino acid synthetic peptide, known as SPIKENET) that was designed to prevent the binding of spike glycoproteins with their receptor(s), angiotensin- converting enzyme 2 (ACE2), and carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) (SARS-CoV-2 and MHV-1, respectively), ameliorated animal death and reversed altered levels of AQPs and oxidative stress post-MHV-1 infection. Collectively, our findings suggest the possible involvement of altered aquaporins and the subsequent edema, likely mediated by the virus-induced inflammatory and oxidative stress response, in the pathogenesis of COVID- 19 and the potential of SPIKENET as a therapeutic option.

COVID-19 is the most consequential pandemic of the 21st century. Since the earliest stage of the 2019-2020 epidemic, animal models have been useful in understanding the etiopathogenesis of SARS-CoV-2 infection and rapid development of vaccines/drugs to prevent, treat or eradicate SARS-CoV-2 infection. Early SARS-CoV-1 research using immortalized in-vitro cell lines have aided in understanding different cells and receptors needed for SARS-CoV-2 infection and, due to their ability to be easily manipulated, continue to broaden our understanding of COVID-19 disease in in-vivo models. The scientific community determined animal models as the most useful models which could demonstrate viral infection, replication, transmission, and spectrum of illness as seen in human populations. Until now, there have not been well-described animal models of SARS-CoV-2 infection although transgenic mouse models (i.e. mice with humanized ACE2 receptors with humanized receptors) have been proposed. Additionally, there are only limited facilities (Biosafety level 3 laboratories) available to contribute research to aid in eventually exterminating SARS-CoV-2 infection around the world. This review summarizes the most successful animal models of SARS-CoV-2 infection including studies in Non-Human Primates (NHPs) which were found to be susceptible to infection and transmitted the virus similarly to humans (e.g., Rhesus macaques, Cynomolgus, and African Green Monkeys), and animal models that do not require Biosafety level 3 laboratories (e.g., Mouse Hepatitis Virus models of COVID-19, Ferret model, Syrian Hamster model). Balancing safety, mimicking human COVID-19 and robustness of the animal model, the Murine Hepatitis Virus-1 Murine model currently represents the most optimal model for SARS-CoV-2/COVID19 research. Exploring future animal models will aid researchers/scientists in discovering the mechanisms of SARS-CoV-2 infection and in identifying therapies to prevent or treat COVID-19.

In the present study, chitin was extracted from marine crustacean shell waste (shrimp, crab, squilla and lobster) using traditional chemical methods (deproteinisation and demineralization) and its physicochemical and structural properties were characterized. The chitin content of crustacean shell waste ranged from 17.50% to 23.75% on a dry weight basis. The molecular weight analyses revealed that the crustacean chitin showed low molecular weight. The results of X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), Energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM) and thermogravimetry/differential thermal analysis (TG/DTA) confirmed that the α-chitins isolated from crustacean shell waste were similar to commercial crustacean chitin. The crystalline index value of the extracted chitin varied from 80.3% to 80.8%. The infrared spectroscopy analysis of the crustacean chitin exhibited two bands at around 1660 and 1620 cm−1. SEM analysis of the extracted chitin showed the nanofibre and nanopore structures. Additionally, thermal stability of the crustacean chitin was close to that of the commercial chitin. Therefore, the results of this study confirmed that the extracted chitin is in α-form.

Background: Breast cancer is the leading cause of cancer death in women worldwide with more than 1. 7 million new cases annually. Major advances have been made in the therapeutic management of this condition in many countries. However, neuropsychiatric disorders in patients with breast cancer constitute a significant concern due to their negative impact on patient's life and on the success of therapy itself.Methodology: In this study we aimed to evaluate psychological disorders in a population of 212 Moroccan women treated for breast cancer within the Mohammed VI Center for the Treatment of Cancers of Casablanca. A questionnaire was designed to this end on the basis of different validated scales, including the Hospital Anxiety Depression Scale (HADS), the Pittsburgh Sleep Quality Index (PSQI), and the Body Image Scale (BIS).Results: Data analysis has shown that 69.3% of participants had significant sleep disorders; 87% suffer from an anxiety-depressive syndrome (ADS), and 83.0% had significant body image dissatisfaction. A positive correlation was shown between ADS and both patients' national health insurance coverage and patients or husbands' education. Analysis further revealed that anxiety and depression were negatively correlated with different types of treatment. Similarly, both BIS and PSQI scores were positively associated with anxiety and depression disorders.Conclusion: The present investigation highlights the need to generalize and strengthen the psychological approach of patients treated for breast cancer in Morocco. We anticipate that such a strategy will alleviate suffering and promote therapy success in these patients and will diminish or prevent conjugal and familial impacts of the illness.

Chitosan based nanocomposite scaffolds have attracted wider applications in medicine, in the area of drug delivery, tissue engineering and wound healing. Chitosan matrix incorporated with nanometallic components has immense potential in the area of wound dressings due to its antimicrobial properties. This review focuses on the different combinations of Chitosan metal nanocomposites such as Chitosan/nAg, Chitosan/nAu, Chitosan/nCu, Chitosan/nZnO and Chitosan/nTiO2 towards enhancement of healing or infection control with special reference to the antimicrobial mechanism of action and toxicity. Keywords: Antimicrobial Chitosan nanocomposities, Silver, Zinc oxide, Gold, Copper, Wound healing

Hydrogels are a class of materials that has the property of injectability and in situ gel formation. This property of hydrogels is manipulated in this study to develop a biomimetic bioresorbable injectable system of alginate nanobeads interspersed in fibrin network. Alginate nanobeads developed by calcium cross-linking yielded a size of 200–500 nm. The alginate nanobeads fibrin hydrogel was formed using dual syringe apparatus. Characterization of the in situ injectable hydrogel was done by SEM, FTIR and Rheometer. The developed hydrogel showed mechanical strength of 19 kPa which provides the suitable compliance for soft tissue engineering. Cytocompatibility studies using human umbilical cord blood derived mesenchymal stem cells showed good attachment, proliferation and infiltration within the hydrogel similar to fibrin gel. The developed in situ forming hydrogel could be a suitable delivery carrier of stem cells for soft tissue regeneration.

Infection with SARS-CoV-2, the virus responsible for the global COVID-19 pandemic, causes a respiratory illness that can severely impact other organ systems and is possibly precipitated by cytokine storm, septic shock, thrombosis, and oxidative stress. SARS-CoV-2 infected individuals may be asymptomatic or may experience mild, moderate, or severe symptoms with or without pneumonia. The mechanisms by which SARS-CoV-2 infects humans are largely unknown. Mouse hepatitis virus 1 (MHV-1)-induced infection was used as a highly relevant surrogate animal model for this study. We further characterized this animal model and compared it with SARS-CoV-2 infection in humans. MHV-1 inoculated mice displayed death as well as weight loss, as reported earlier. We showed that MHV-1-infected mice at days 7–8 exhibit severe lung inflammation, peribronchiolar interstitial infiltration, bronchiolar epithelial cell necrosis and intra-alveolar necrotic debris, alveolar exudation (surrounding alveolar walls have capillaries that are dilated and filled with red blood cells), mononuclear cell infiltration, hyaline membrane formation, the presence of hemosiderin-laden macrophages, and interstitial edema. When compared to uninfected mice, the infected mice showed severe liver vascular congestion, luminal thrombosis of portal and sinusoidal vessels, hepatocyte degeneration, cell necrosis, and hemorrhagic changes. Proximal and distal tubular necrosis, hemorrhage in interstitial tissue, and the vacuolation of renal tubules were observed. The heart showed severe interstitial edema, vascular congestion, and dilation, as well as red blood cell extravasation into the interstitium. Upon examination of the MHV-1 infected mice brain, we observed congested blood vessels, perivascular cavitation, cortical pericellular halos, vacuolation of neuropils, darkly stained nuclei, pyknotic nuclei, and associated vacuolation of the neuropil in the cortex, as well as acute eosinophilic necrosis and necrotic neurons with fragmented nuclei and vacuolation in the hippocampus. Our findings suggest that the widespread thrombotic events observed in the surrogate animal model for SARS-CoV-2 mimic the reported findings in SARS-CoV-2 infected humans, representing a highly relevant and safe animal model for the study of the pathophysiologic mechanisms of SARS-CoV-2 for potential therapeutic interventions.

The adrenal glands produce a variety of hormones that play a key role in the regulation of blood pressure, electrolyte homeostasis, metabolism, immune system suppression, and the body’s physiologic response to stress. Adrenal neoplasms can be asymptomatic or can overproduce certain hormones that lead to different clinical manifestations. Oncocytic adrenal neoplasms are infrequent tumors that arise from cells in the adrenal cortex and display a characteristic increase in the number of cytoplasmic mitochondria. Since the rate-limiting step in steroidogenesis includes the transport of cholesterol across the mitochondrial membranes, in part carried out by the 18-kDa translocator protein (TSPO), we assessed the expression of TSPO in a case of adrenal oncocytic neoplasm using residual adrenal gland of the patient as internal control. We observed a significant loss of TSPO immunofluorescence expression in the adrenal oncocytic tumor cells when compared to adjacent normal adrenal tissue. We further confirmed this finding by employing Western blot analysis to semiquantify TSPO expression in tumor and normal adrenal cells. Our findings could suggest a potential role of TSPO in the tumorigenesis of this case of adrenocortical oncocytic neoplasm.