The polybasic furin cleavage site insertion with four amino acid motifs (PRRA) in spike protein's S1/S2 junction site is important in determining viral infectivity, transmission, and host range. However, there is no review so far explaining the effect of the furin cleavage site of the spike protein on SARS‐CoV‐2 replication and pathogenesis in the host and immune responses and vaccination. Therefore, here we specifically focused on genomic evolution and properties of the cleavage site of spike protein in the context of SARS‐CoV‐2 followed by its effect on viral entry, replication, and pathogenesis. We also explored whether the spike protein furin cleavage site affected the host immune responses and SARS‐CoV‐2 vaccination. This review will help to provide novel insights into the effects of polybasic furin cleavage site on the current COVID‐19 pandemic.

Diffuse reflectance spectroscopy is a widely used technique for medical applications that may analyze the optical characteristics of biological tissues. By using diffuse reflectance spectroscopy, different tissue types can be distinguished based on specific changes on reflected light spectrum that are a result of differences on a molecular level between compared tissues. Identification of the structural features of tissue can be performed by applying diffuse reflectance spectroscopy, and the spectra obtained from this technique could provide important diagnostic information about the tissue morphology and physiology. Moreover, different tissue types can be classified using diffuse reflectance spectroscopy, during surgery on the basis of their optical properties that are related to the tissue morphology and constituents. In recent years, several research groups have been shown the feasibility of diffuse reflectance spectroscopy in discriminating benign and malignant tissue, and thus making it a good competitor for margin assessment. Therefore, the diffuse reflectance spectroscopy has the possibility to become an important optical means for disease diagnosis, treatment and prognosis monitoring. This review represents a summary of the literature on diffuse reflectance spectroscopy and its important clinical applications.

Around 350 million people are living with hepatitis B virus (HBV), which can lead to death due to liver cirrhosis and hepatocellular carcinoma (HCC). Various antiviral drugs/nucleot(s)ide analogues are currently used to reduce or arrest the replication of this virus. However, many studies have reported that nucleot(s)ide analogue-resistant HBV is circulating. Cellular signaling pathways could be one of the targets against the viral replication. Several studies reported that viral proteins interacted with mitochondrial proteins and localized in the mitochondria, the powerhouse of the cell. And a recent study showed that mitochondrial turnover induced by thyroid hormones protected hepatocytes from hepatocarcinogenesis mediated by HBV. Strong downregulation of numerous cellular signaling pathways has also been reported to be accompanied by profound mitochondrial alteration, as confirmed by transcriptome profiling of HBV-specific CD8 T cells from chronic and acute HBV patients. In this review, we summarize the ongoing research into mitochondrial proteins and/or signaling involved with HBV proteins, which will continue to provide insight into the relationship between mitochondria and HBV and ultimately lead to advances in viral pathobiology and mitochondria-targeted antiviral therapy.

This study was carried out for the isolation and identification of Avibacterium paragallinarum, the etiological agent of infectious coryza (IC). Pathological changes were also investigated that occurred in organs in layer chickens obtained from some selected areas of Bangladesh. A nasal swabs (n=30) from dead chickens and four swabs from live chickens were collected aseptically. The organisms from swabs were cultured in different media, stained, and followed by sugar fermentation and biochemical tests for identification of causal agent. Histopathology of the affected tissues was also carried out. Swabs from nasal passage (n=30) of dead birds died of other diseases cultured but no A. paragallinarum was isolated and identified. Two out of four suspected clinical cases of IC was confirmed by isolation of A. paragallinarum. The clinical signs of all four cases were nasal discharge; conjunctivitis with swelling of the sinuses, face and wattles; decreased feed and water intake with reduced egg production. At necropsy, hemorrhages were in mucous membrane of nasal passage and trachea. Histopathology of the nasal septum showed acanthosis, congestion, mucous glandular cell hyperplasia, hyperplasia of nasal sinus and parakeratosis. Further studies involving serological and molecular identification of the etiological agent of IC are warranted. DOI: http://dx.doi.org/10.3329/jbau.v11i1.18218 J. Bangladesh Agril. Univ. 11(1): 87-96, 2013

Neuropilin-1 (NRP1) is a recently identified glycoprotein that is an important host factor for SARS-CoV-2 infection. On the other hand, angiotensin-converting enzyme-2 (ACE2) acts as a receptor for SARS-CoV-2. Additionally, both NRP1 and ACE2 express in the kidney and are associated with various renal diseases, including renal carcinoma. Therefore, the expression profiles of NRP1 and ACE2 in kidney renal clear cell carcinoma (KIRC) and kidney renal papillary cell carcinoma (KIRP) patients from the various cancer databases were investigated along with their impact on patients’ survivability. In addition, coexpression analysis of genes involved in COVID-19, KIRC, and KIRP concerning NRP1 and ACE2 was performed. The results demonstrated that both t NRP1 and ACE2 expressions are upregulated in KIRC and KIRP compared to healthy conditions and are significantly correlated with the survivability rate of KIRC patients. A total of 128 COVID-19-associated genes are coexpressed, which are positively associated with NRP1 and ACE2 both in KIRC and KIRP. Therefore, it might be suggested that, along with the ACE2, high expression of the newly identified host factor NRP1 in renal carcinomas may play a vital role in the increased risk of SARS-CoV-2 infection and survivability of COVID-19 patients suffering from kidney cancers. The findings of this investigation will be helpful for further molecular studies and prevention and/or treatment strategies for COVID-19 patients associated with renal carcinomas.

Serious health risks have been connected to ongoing, escalating exposure to environmental toxins and one of them is acrylamide (ACR), an organic compound. Although there are many published reports on ACR toxicity, limited information is available regarding the use of two potential antioxidants against ACR-instigated reproductive toxicity. The study focused on investigating the protective effects of vitamin C and 5-ASA against ACR-incited reproductive toxicity. A total of 50 male mice aged 4 weeks old were treated for 90 days with different concentrations either of ACR or ACR and vitamin C or ACR and 5- ASA or ACR, vitamin C, and 5- ASA. ACR significantly reduced serum testosterone level (p = 0.0037), sperm concentration (p = 0.0004), and percentage of sperm motility (p = 0.003), as well as increased sperm abnormality; head (p = 0.0058), tail (p = 0.001), and midpiece (p = 0.0339). Besides, the weight (p = 0.0006) and length (p = 0.0105) of testes, as well as weight (p = 0.0001) and length (p = 0.0021) of epididymis were decreased along with atrophy of seminiferous tubules of the testis, and disintegration of the tubular epithelium of epididymis on ACR exposed mice which were improved by vitamin C and 5-ASA administration. Vitamin C and 5-ASA can potentially mitigate the negative effects of ACR on male reproduction; however, combined application is recommended for better performance. In Bangladesh, this work is anticipated to address the health benefits of vitamin C and 5-ASA, particularly in improving the reproductive health of males against ACR toxicity.