New Records of the Spider Fauna From Sarawak, Malaysia

SHORT COMMUNICATION New Records of the Spider Fauna from Sarawak, Malaysi

Age, Disease Severity and Ethnicity Influence Humoral Responses in a Multi-Ethnic COVID-19 Cohort

The COVID-19 pandemic has affected all individuals across the globe in some way. Despite large numbers of reported seroprevalence studies, there remains a limited understanding of how the magnitude and epitope utilization of the humoral immune response to SARS-CoV-2 viral anti-gens varies within populations following natural infection. Here, we designed a quantitative, multi-epitope protein microarray comprising various nucleocapsid protein structural motifs, including two structural domains and three intrinsically disordered regions. Quantitative data from the microarray provided complete differentiation between cases and pre-pandemic controls (100% sensitivity and specificity) in a case-control cohort (n = 100). We then assessed the influence of disease severity, age, and ethnicity on the strength and breadth of the humoral response in a multi-ethnic cohort (n = 138). As expected, patients with severe disease showed significantly higher antibody titers and interestingly also had significantly broader epitope coverage. A significant increase in antibody titer and epitope coverage was observed with increasing age, in both mild and severe disease, which is promising for vaccine efficacy in older individuals. Additionally, we observed significant differences in the breadth and strength of the humoral immune response in relation to ethnicity, which may reflect differences in genetic and lifestyle factors. Furthermore, our data enabled localization of the immuno-dominant epitope to the C-terminal structural domain of the viral nucleocapsid protein in two independent cohorts. Overall, we have designed, validated, and tested an advanced serological assay that enables accurate quantitation of the humoral response post natural infection and that has revealed unexpected differences in the magnitude and epitope utilization within a population

Field Survey of Foliage-dwelling Spiders (Arachnida, Araneae) in Peninsular Malaysia

Diversity of spider groups have received less research attention and there are limited published references for spiders from Peninsular Malaysia. The current survey was conducted to locate and identify foliage-dwelling spiders (Arachnida, Araneae) at five different sites in Peninsular Malaysia. Spider specimens were collected using manual search and sweep-netting between September 2012 and November 2012. A total of 92 morpho-species from 65 genera that belong to 15 families have been successfully recorded and identified. The greatest proportion of specimens captured (40%) were Foliage-runners (Clubionidae, Miturgidae, Oxyopidae, Pisauridae, Salticidae, Scytodidae, Thomisidae), followed by orb-weavers (Araniedae, Nephilidae, Tetragnathidae, Uloboridae) (36.5%), space-weavers (Pholcidae, Psechridae Theridiidae) (21.5%) and ground-dwellers (Sparassidae) (2.0%). Cluster analysis has revealed that the same habitat types share a more similar diversity composition compared to different habitat types, which indicates that spider assemblage composition was partly co-dependent on vegetation structure. However, no significant difference in spider assemblage composition was found between all the five sites which follows that these diurnal group of spiders are actually adaptable to various habitat types

Tumorigenic role of podoplanin in esophageal squamous-cell carcinoma

Background. Podoplanin, a mucin-type transmembrane glycoprotein, is thought to be one of the cancer stem cell markers for squamous-cell carcinoma of the vulva. The objectives of the present study were to examine the role of podoplanin in esophageal squamous-cell carcinoma (ESCC). Methods. Expression of podoplanin was examined immunohistochemically in 61 cases of ESCC that had not been treated with chemotherapy or radiotherapy before surgery. Because cancer stem-cell quantities have been reported to increase with chemotherapy and radiotherapy, cases in patients who did not receive such prior therapies were included in this study. Cases with[10% tumor cells showing signals for podoplanin were categorized as podoplanin high, and the others were classified as podoplanin low. The effects of podoplanin on the behavior of cancer cells were evaluated in ESCC cell lines in which podoplanin expression was knocked down. Results. To examine whether podoplanin could be used as a cancer stem cell marker for ESCC, podoplanin-positive and podoplanin-negative fractions were sorted separately from the ESCC cell line and cultured. Podoplanin-positive ESCC cells yielded both podoplanin-positive and podoplanin- negative cells, whereas few cells were obtained from podoplanin-negative ESCC cells. When podoplanin expression was knocked down, ESCC cell lines became vulnerable to anticancer drugs and showed defective invasion and tumorigenic activities. Nineteen (31.1%) of 61 cases were categorized as podoplanin high. Podoplaninhigh cases were correlated with T category, stage of disease, lymphatic and vascular invasion, recurrence, and prognosis of patients. Podoplanin-low cases showed better overall and disease-free survival. Conclusions. There is a role for podoplanin in tumorigenesis and malignant progression in ESCC. Cancer cells comprise a heterogeneous group of cells, among which only a small population of cells possesses the ability to reconstitute a whole tumor.1–3 This population, called cancer stem cells (CSCs), efficiently forms colonies in semisolid culture and is xenotransplantable in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice.4 CSCs were first identified in leukemia and subsequently isolated from solid tumors, such as those of breast, brain, prostate, melanoma, colon, pancreas, head/neck, liver, and gastric cancers.5–15 CSCs are known to be resistant to chemotherapy and radiotherapy and are more invasive than non-CSCs. Recognition of CSCs and their efficient elimination may be a valuable strategy for treatment of cancers. Therefore, studies to search for markers of CSCs have been performed. First, successful isolation of CD34? CD38- leukemic stem cells was reported.5 However, subsequent studies showed that markers for CSCs differ among cancers originating from different organs. Atsumi et al. reported that podoplanin, a mucin-type transmembrane glycoprotein, is a possible candidate CSC marker for squamous-cell carcinoma (SCC).16 Cultured cells from the SCC cell line A431, which is derived from the vulva, consist of two populations: podoplanin-positive and podoplanin-negative cells. CSCs are known to produce both CSC and non-CSC

Methanol extract of Melastoma malabathricum leaves exerted antioxidant and liver protective activity in rats

Background Melastoma malabathricum L. (Melastomaceae) is a small shrub with various medicinal uses. The present study was carried out to determine the hepatoprotective activity of methanol extract of M. malabathricum leaves (MEMM) against the paracetamol-induced liver toxicity in rats model. Methods The respective chemicals and herbal solutions (10% DMSO, 200 mg/kg silymarin or MEMM (50, 250 and 500 mg/kg)) were administered orally to rats once everyday for 7 days followed by the hepatotoxicity assay. The blood samples and livers were collected and subjected to biochemical and microscopical analysis. Prior to the hepatoprotective study, MEMM was subjected to determination of the total phenolic content (TPC) and the antioxidant properties using several standard assays (e.g. 2, 2-diphenyl-1-picrylhydrazyl- and superoxide anion- radical scavenging assay, and oxygen radical absorbance capacity assay). Results MEMM exerted significant (p < 0.05) and high antioxidant activity in which high TPC was recorded; while in the hepatotoxicity study, the extract exhibited significant hepatoprotective effects against the paracetamol-induced hepatotoxic model. The results observed for serum liver enzymes (ALT, ALP and AST) as well as the microscopic observations and microscopic scoring supported the hepatoprotective potential of MEMM. The phytochemical and HPLC analysis of MEMM demonstrated the presence of flavonoids as its major constituents. Conclusions The MEMM-induced hepatoprotective activity could be allied partly to its antioxidant activity and the presence of flavonoids

Hepatoprotective action of various partitions of methanol extract of Bauhinia purpurea leaves against paracetamol-induced liver toxicity: involvement of the antioxidant mechanisms

Background: Methanol extract of Bauhinia purpurea L. (family Fabaceae) (MEBP) possesses high antioxidant and anti-inflammatory activities and recently reported to exert hepatoprotection against paracetamol (PCM)-induced liver injury in rats. In an attempt to identify the hepatoprotective bioactive compounds in MEBP, the extract was prepared in different partitions and subjected to the PCM-induced liver injury model in rats. Methods: Dried MEBP was partitioned successively to obtain petroleum ether (PEBP), ethylacetate (EABP) and aqueous (AQBP) partitions, respectively. All partitions were subjected to in vitro antioxidant (i.e. total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH)- and superoxide-radicals scavenging assay, and oxygen radical absorbance capacity (ORAC) assay) and anti-inflammatory (i.e. lipooxygenase (LOX) and xanthine oxidase (XO) assay) analysis. The partitions, prepared in the dose range of 50, 250 and 500 mg/kg, together with a vehicle (10 % DMSO) and standard drug (200 mg/kg silymarin) were administered orally for 7 consecutive days prior to subjection to the 3 mg/kg PCM-induced liver injury model in rats. Following the hepatic injury induction, blood samples and liver were collected for the respective biochemical parameter and histopathological studies. Body weight changes and liver weight were also recorded. The partitions were also subjected to the phytochemical screening and HPLC analysis. Results: Of all partitions, EABP possessed high TPC value and demonstrated remarkable antioxidant activity when assessed using the DPPH- and superoxide-radical scavenging assay, as well as ORAC assay, which was followed by AQBP and PEBP. All partitions also showed low anti-inflammatory activity via the LOX and XO pathways. In the hepatoprotective study, the effectiveness of the partitions is in the order of EABP>AQBP>PEBP, which is supported by the microscopic analysis and histopathological scoring. In the biochemical analysis, EABP also exerted the most effective effect by reducing the serum level of alanine transaminase (ALT) and aspartate transaminase (AST) at all doses tested in comparison to the other partitions. Phytochemical screening and HPLC analysis suggested the presence of: flavonoids, condensed tannins and triterpenes in EABP; flavonoids, condensed tannins and saponins in PEBP and; only saponins in AQBP. Conclusion: EABP demonstrates the most effective hepatoprotection against PCM-induced liver injury in rats. This observation could be attributed to its remarkable antioxidant activity and the presence of flavonoids that might probably act synergistically with other biocompounds to cause the hepatoprotection