The calcium-activated chloride channel-associated protein rCLCA2 is expressed throughout rat epidermis, facilitates apoptosis and is downmodulated by UVB.

The rodent chloride channel regulatory proteins mCLCA2 and its porcine and human homologues pCLCA2 and hCLCA2 are expressed in keratinocytes but their localization and significance in the epidermis have remained elusive. hCLCA2 regulates cancer cell migration, invasion and apoptosis, and its loss predicts poor prognosis in many tumors. Here, we studied the influences of epidermal maturation and UV-irradiation (UVR) on rCLCA2 (previous rCLCA5) expression in cultured rat epidermal keratinocytes (REK) and correlated the results with mCLCA2 expression in mouse skin in vivo. Furthermore, we explored the influence of rCLCA2 silencing on UVR-induced apoptosis. rClca2 mRNA was strongly expressed in REK cells, and its level in organotypic cultures remained unchanged during the epidermal maturation process from a single cell layer to fully differentiated, stratified cultures. Immunostaining confirmed its uniform localization throughout the epidermal layers in REK cultures and in rat skin. A single dose of UVR modestly downregulated rClca2 expression in organotypic REK cultures. The immunohistochemical staining showed that CLCA2 localized in basal and spinous layers also in mouse skin, and repeated UVR induced its partial loss. Interestingly, silencing of rCLCA2 reduced the number of apoptotic cells induced by UVR, suggesting that by facilitating apoptosis, CLCA2 may protect keratinocytes against the risk of malignancy posed by UVB-induced corrupt DNA.

Prevalence of cirrhotic cardiomyopathy and its relationship with serum pro-brain natriuretic peptide, hepatorenal syndrome, spontaneous bacterial peritonitis, and mortality.

OBJECTIVES: This study aims at estimating the prevalence of cirrhotic cardiomyopathy in a cohort of cirrhosis patients in northern India using the World Congress of Gastroenterology 2005 criteria and its relationship with grades of cirrhosis, its complications, and all-cause mortality. METHODS: This was a prospective study in which 53 cirrhosis patients underwent the 2D color Doppler, and tissue Doppler echocardiography. Echocardiography findings were compared with thirty age- and sex-matched healthy controls. Additionally, serum pro-brain natriuretic peptide (pro-BNP) and troponin-T levels were measured. Patients were followed up for 6 months to look for complications and mortality. RESULT: 2D echocardiography findings revealed that diastolic cardiomyopathy with no gross systolic dysfunction was significantly prevalent in cirrhosis patients. Using the Montreal criteria, we found the incidence of diastolic cardiomyopathy to be 56.6%. Tissue Doppler echocardiography findings were also correlated. Diastolic dysfunction correlated with the severity of cirrhosis, and patients with higher Child score had more diastolic dysfunction. Serum pro-BNP levels and QTc interval were also higher in patients with diastolic dysfunction. On survival analysis, patients with cirrhotic cardiomyopathy had shorter survival and greater frequency of encephalopathy and hepatorenal syndrome (HRS) episodes as compared with cirrhotic patients without cardiomyopathy, though the differences were not statistically significant. CONCLUSION: The study showed that diastolic dysfunction was highly prevalent (56.6% of the study population) in cirrhosis patients. QTc interval and pro-BNP were also significantly raised. Also, complications of cirrhosis like HRS, spontaneous bacterial peritonitis, and hepatic encephalopathy were more common in the cirrhotic cardiomyopathy group.

A Review of the Diagnosis and Management of Hepatitis E.

Purpose of review: We aim to provide the readers an up-to-date knowledge of the structure, epidemiology, and transmission followed by a detailed discussion on testing, diagnostics and management of hepatitis E virus infection. We have also included a comprehensive review of hepatitis E in pregnancy. Recent findings: European Association for the Study of the Liver established clinical practice guidelines for testing and treatment of suspected hepatitis E virus infections in 2018. Evidence suggests chronic hepatitis E may follow a course similar to hepatitis B/C with progression to cirrhosis and possibly hepatocellular carcinoma in immunocompromised patients. Summary: Hepatitis E virus is the most common cause of acute viral hepatitis worldwide. A combination of serology and nucleic acid amplification testing is the recommended strategy for suspected patients. Ribavirin therapy for a period of 3 months is the drug of choice for severe acute hepatitis, acute-on chronic liver failure, and chronic infections from hepatitis E virus in immunocompromised patients who are unresponsive to decreased immunosuppression. PEGylated interferon α can be used for ribavirin-resistant liver transplant patients with chronic hepatitis E. Further research in therapeutic options is essential considering the stormy course of hepatitis E infection during pregnancy and teratogenicity of all available options.

Effects of mutations in the post-translational modification sites on the trafficking of hyaluronan synthase 2 (HAS2).

Vesicular trafficking of hyaluronan synthases (HAS1-3) from endoplasmic reticulum (ER) through Golgi to plasma membrane (PM), and either back to endosomes and lysosomes, or out into extracellular vesicles, is important for their activities. We studied how post-translational modifications affect the trafficking of HAS2 by mutagenesis of the sites of ubiquitination (K190R), phosphorylation (T110A) and O-GlcNAcylation (S221A), using Dendra2- and EGFP-HAS2 transfected into COS1 cells. Confocal microscopy showed HAS2 wild type (wt) and its K190R and S221A mutants in ER, Golgi and extracellular vesicles, while the T110A mutant remained mostly in the ER. HA synthesis was reduced by S221A, while completely blocked by K190R and T110A. Cell-surface biotinylation indicated that T110A was absent from PM, while S221A was close to the level of wt, and K190R was increased in PM. TIRF microscopy analysis gave similar results. Rab10 silencing increased HA secretion by HAS2, likely by inhibiting endocytosis of the enzyme from PM, as reported before for HAS3. Green-to-red photo-conversion of Dendra2-HAS2 constructs suggested slower decay of K190R and S221A than HAS2 wt, while T110A was barely degraded at all. S221D and S221E, the phosphomimetic mutants of this site, decayed faster and blocked hyaluronan synthesis, suggesting alternative O-GlcNAc/-PO4 substitution to regulate the stability of the enzyme. Probing the role of dynamic O-GlcNAcylation at S221 by adding glucosamine increased the half-life of only HAS2 wt. The Dendra2·HAS2 disappearance from Golgi was slower for K190R. Of the two inactive constructs, K190R co-transfected with HAS2 wt suppressed, whereas T110A had no effect on HA synthesis. Interestingly, the HAS2-stimulated shedding of extracellular vesicles was dependent on HAS residence in PM but independent of HA synthesis. The results indicate that post-translational modifications control the trafficking of HAS2, and that trafficking is an integral part of the post-translational regulation of HAS2 activity.

Hyaluronan metabolism enhanced during epidermal differentiation is suppressed by vitamin C.

BACKGROUND: Hyaluronan is a large, linear glycosaminoglycan present throughout the narrow extracellular space of the vital epidermis. Increased hyaluronan metabolism takes place in epidermal hypertrophy, wound healing and cancer. Hyaluronan is produced by hyaluronan synthases and catabolized by hyaluronidases, reactive oxygen species and KIAA1199. OBJECTIVES: To investigate the changes in hyaluronan metabolism during epidermal stratification and maturation, and the impact of vitamin C on these events. METHODS: Hyaluronan synthesis and expression of the hyaluronan-related genes were analysed during epidermal maturation from a simple epithelium to a fully differentiated epidermis in organotypic cultures of rat epidermal keratinocytes using quantitative reverse transcriptase polymerase chain reaction, immunostaining and Western blotting, in the presence and absence of vitamin C. RESULTS: With epidermal stratification, both the production and the degradation of hyaluronan were enhanced, resulting in an increase of hyaluronan fragments of various sizes. While the mRNA levels of Has3 and KIAA1199 remained stable during the maturation, Has1, Has2 and Hyal2 showed a transient upregulation during stratification, Hyal1 transcription remained permanently increased and transcription of the hyaluronan receptor, Cd44, decreased. At maturation, vitamin C downregulated Has2, Hyal2 and Cd44, whereas it increased high-molecular-mass hyaluronan in the epidermis, and reduced small fragments in the medium, suggesting stabilization of epidermal hyaluronan. CONCLUSIONS: Epidermal stratification and maturation is associated with enhanced hyaluronan turnover, and release of large amounts of hyaluronan fragments. The high turnover is suppressed by vitamin C, which is suggested to enhance normal epidermal differentiation in part through its effect on hyaluronan.

Hyaluronan synthase 1 (HAS1) produces a cytokine-and glucose-inducible, CD44-dependent cell surface coat.

Hyaluronan is a ubiquitous glycosaminoglycan involved in embryonic development, inflammation and cancer. In mammals, three hyaluronan synthase isoenzymes (HAS1-3) inserted in the plasma membrane produce hyaluronan directly on cell surface. The mRNA level and enzymatic activity of HAS1 are lower than those of HAS2 and HAS3 in many cells, obscuring the importance of HAS1. Here we demonstrate using immunocytochemistry and transfection of fluorescently tagged HAS1 that its enzymatic activity depends on the ER-Golgi-plasma membrane traffic, like reported for HAS2 and HAS3. When cultured in 5 mM glucose, HAS1-transfected MCF-7 cells show very little cell surface hyaluronan, detected with a fluorescent hyaluronan binding probe. However, a large hyaluronan coat was seen in cells grown in 20 mM glucose and 1 mM glucosamine, or treated with IL-1ß, TNF-α, or TGF-ß. The coats were mostly removed by the presence of hyaluronan hexasaccharides, or Hermes1 antibody, indicating that they depended on the CD44 receptor, which is in a contrast to the coat produced by HAS3, remaining attached to HAS3 itself. The findings suggest that HAS1-dependent coat is induced by inflammatory agents and glycemic stress, mediated by altered presentation of either CD44 or hyaluronan, and can offer a rapid cellular response to injury and inflammation.

Estimation of stature from foot length in adult Nepalese population and its clinical relevance.

BACKGROUND: Stature is the height of the person in the upright posture. It is an important measure of physical identity. Interrelationships among different body measurements may be used to estimate one from another in case of missing body parts. OBJECTIVE: Stature is an important indicator for identification. There are numerous means to establish stature and their significance lies in the simplicity of measurement, applicability and accuracy in prediction. The current study dealt with developing a regression equation for stature estimation from foot length and to find out the correlation between body height and foot length of Nepalese people. METHODS: The present study was carried out to establish the regression equation and correlation coefficient between individual height and mean foot length. It was conducted on 440 students of age group 17 to 25 years studying in Kathmandu University School of Medical Sciences, Dhulikhel, Nepal. Body height and foot length were measured in centimeter. RESULTS: There was significant correlation between height and foot length (r = 0. 703, p < 0.01).The regression equation for height and foot length was found to be Y = 3.179 X + 87.65, where X is the foot length and Y the height. CONCLUSIONS: This study will help in medico-legal cases in establishing identity of an individual and this would be useful for Anatomists and Anthropologists to calculate stature of adult Nepalese based on foot length.