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N-butanol has unique physicochemical and combustion properties, similar to gasoline, which makes it an environmentally friendly alternative to conventional fuels. To improve the efficiency, the dehydration of butanol is necessary. This paper aims to investigate the performance of Deep Eutectic Solvents (DESs) based membranes for the dehydration of n-butanol by the pervaporation process. Three DES with different combinations of hydrogen bond donors and acceptors, i.e., DL-menthol: Lauric acid (DES), DL-menthol-Palmitic acid (DES), and [TETA] Cl: Thymol (DES), were used. We hypothesized that (i) incorporation of hydrophobic DES would increase the hydrophobicity of the membranes; (ii) specific functional groups (phenolic group, amine group) in DESs would enhance the butanol-philic character of membranes, and (iii) hydrophobic DESs would increase the butanol separation efficiency and permeability of membranes. FTIR analysis and physicochemical parameters of the resultant liquid mixture validated the DESs' production. The DESs were then filled into the permeable support, resulting in supported liquid membranes (SLMs). An additional layer of polydimethylsiloxane (PDMS) was coated directly on the DES-PSf layer to prevent leaching out of DES. A feed containing a 6 wt % aqueous solution of butanol under varying temperatures was studied. The results showed that among all membranes, [TETA] Cl: Thymol DES-based membrane showed the highest sorption of 36% at room temperature. The introduction of DES in membranes resulted in a remarkable increase in the separation factor while sustaining a reasonable flux. Among all the membranes, the DL-menthol: Lauric acid (DES) based membrane exhibited the highest separation factor of 57 with a total flux of 0.11 kg/m2. h. Significantly high butanol-water separation was attributed to the low viscosity and high butanol solubility of the chosen DES, which makes it a suitable substitute to conventional ILs.

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BACKGROUND: The purpose to perform this study was to screen blood donors for possible occult HBV by checking the seroprevalence of the hepatitis B antibodies in blood donors. It was a Cross-sectional study conducted at Blood Bank of Lahore General Hospital Lahore from April to June 2015 (3-months). METHODS: In this prospective study, 180 healthy blood donors, presenting to the blood bank of Lahore General Hospital were selected. Their detailed demographic data and blood samples were collected. HBsAg testing was done by ELISA and further HBc IgM testing was also done by ELISA. Those testing positive for HBc IgM were further evaluated by real-time PCR to detect HBV DNA. RESULTS: Mean duration of the life span was 26.51 years with a range of 18-61 years. Sex distribution show 93.9% (n=169) males and 6.1% (n=11) females. HBsAg was positive in 3.3% (n=6) while their HBc IgM was negative and HBc IGM was positive in 2.2% (n=4) of the healthy donors in whom HBsAg was found negative by ICT method. further qualitative HBV DNA by rt-PCR was done on those positive with anti HBc IgM and no patient had HBV DNA detected from their blood. CONCLUSION: Without routine screening of the sera for the HBc Antibody, the low-level HBV viraemia may not be detected as the nonappearance of the surface antigen in the blood of apparently healthy donors do not ensure the absence of circulating virus in the blood of these donors.

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MicroRNAs (miRNAs) are small, non-coding RNAs that regulate a variety of biological processes. Recently, human liver-specific miRNA miR-122 has been reported to facilitate hepatitis C virus (HCV) replication in liver cells. HCV is one of the leading causes of liver diseases worldwide. In Pakistan, the estimated prevalence is up to 10%. Here, we report hepatic and serum miR-122 expression profiling from paired liver and serum samples from treatment-naive chronic hepatitis C (CHC) patients and controls. We aimed to elucidate the biomarker potential of serum miR-122 for monitoring disease progression and predicting end treatment response (ETR). Hepatic miR-122 levels were significantly down-regulated in CHC patients. A significant inverse correlation was observed between hepatic and serum miR-122 levels, indicating that serum miR-122 levels reflect HCV-associated disease progression. Both hepatic and serum miR-122 were significantly correlated (P < 0.05) with several clinicopathological features of CHC. Receiver operator curve analysis showed that serum miR-122 had superior discriminatory ability even in patients with normal alanine transaminase levels. Multivariate logistic regression analysis highlighted pre-treatment serum miR-122 levels as independent predictors of ETR. In conclusion, serum miR-122 holds the potential to serve as a promising biomarker of disease progression and ETR in CHC patients.

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The development of secondary batteries based on abundant and cheap elements is vital. Among various alternatives to conventional lithium-ion batteries, sodium-ion batteries (SIBs) are promising due to the abundant resources and low cost of sodium. While there are many challenges associated with the SIB system, cathode is an important factor in determining the electrochemical performance of this battery system. Accordingly, ongoing research in the field of SIBs is inclined towards the development of safe, cost effective cathode materials having improved performance. In particular, pyrophosphate cathodes have recently demonstrated decent electrochemical performance and thermal stability. Herein, we report the synthesis, electrochemical properties, and thermal behavior of a novel Na2Fe0.5Mn0.5P2O7 cathode for SIBs. The material was synthesized through a solid state process. The structural analysis reveals that the mixed substitution of manganese and iron has resulted in a triclinic crystal structure (P1[combining macron] space group). Galvanostatic charge/discharge measurements indicate that Na2Fe0.5Mn0.5P2O7 is electrochemically active with a reversible capacity of ∼80 mA h g(-1) at a C/20 rate with an average redox potential of 3.2 V. (vs. Na/Na(+)). It is noticed that 84% of initial capacity is preserved over 90 cycles showing promising cyclability. It is also noticed that the rate capability of Na2Fe0.5Mn0.5P2O7 is better than Na2MnP2O7. Ex situ and CV analyses indicate that Na2Fe0.5Mn0.5P2O7 undergoes a single phase reaction rather than a biphasic reaction due to different Na coordination environment and different Na site occupancy when compared to other pyrophosphate materials (Na2FeP2O7 and Na2MnP2O7). Thermogravimetric analysis (25-550 °C) confirms good thermal stability of Na2Fe0.5Mn0.5P2O7 with only 2% weight loss. Owing to promising electrochemical properties and decent thermal stability, Na2Fe0.5Mn0.5P2O7, can be an attractive cathode for SIBs.

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INTRODUCTION: Hepatitis C virus (HCV) is one of the most important causes of chronic liver diseases, which include inflammation, fibrosis, cirrhosis and hepatocellular carcinoma. Several factors have been proposed to determine the clinical outcome of HCV infection. The accurate mechanism by which HCV damages the liver remains poorly understood. In chronic hepatitis C patients, the relation between serum biochemical markers, HCV RNA titers and histological liver injury remain controversial. OBJECTIVES: The aim of this study was to investigate the relation between serum biochemical markers, HCV RNA titers and the degree of liver damage in patients with chronic HCV. MATERIALS AND METHODS: Liver biopsies were performed on 79 of a total of 100 enrolled patients. The histological activity was evaluated by the METAVER scoring system. HCV RNA quantification was performed by quantitative real-time PCR, and HCV genotyping was performed by nested PCR. Biochemical markers were measured with biochemical instruments. RESULTS: HCV RNA titers were significantly correlated with aspartate aminotransferase (AST) (P=0.004), alkaline phosphatase (ALP) (P=0.001) and total bilirubin (P=0.012) levels. HCV RNA titers were also significantly correlated with a progression of the fibrosis stage (P=0.000), but no correlation was observed with the change in inflammatory grades. It was observed that bilirubin levels were higher in later fibrosis stages as compared with the initial stage (P=0.000). Results revealed that in different fibrosis stages, the levels of AST (P=0.000), ALP (P=0.000) and alanine aminotransferase (ALT) (P=0.008), the age at diagnosis (P=0.000), the present age (P=0.000) and the BMI (P=0.009) were statistically significant. In the case of the inflammatory grade, levels of bilirubin (P=0.000), ALP (P=0.000), AST (P=0.016) and ALT (P=0.000) were statistically different between the inflammatory grades. CONCLUSION: Serum HCV RNA titers were correlated with AST, ALP and total bilirubin. Levels of ALT, AST, ALP and bilirubin had significant relation with the liver fibrosis stage and the inflammatory grade in genotype 3a. Hence, our study suggests that AST, ALP and ALT may correlate with liver damage.

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INTRODUCTION: Dengue virus (DENV) affects over half the world's population in 112 countries, and dengue fever (DF) is the second largest arthropod borne infectious global hazard after malaria with complications like Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS), accounting for significant morbidity and mortality world-over. Pakistan is significantly affected with DENV infection and to-date no study identifying risk factors associated with development of severe complications of DF has been done. METHODS: 997 confirmed cases of DF were collected from a tertiary care hospital in Lahore, Pakistan and their clinical and biochemical data were collected. Univariate, multivariate and logistics regression analysis was performed to identify risk factors associated with development of DHF and DSS. RESULTS: Bleeding OR 70.7 (CI 38.4-129.9), deranged liver function test OR 1.9 (CI 0.97-0.99), presence of urinary red blood cells OR 1.4 (95%CI 0.179-0.900) and presence of urinary protein OR 1.1 (95%CI 0.191-0.974) were related to development of DHF and DSS. DISCUSSION: Severe Dengue, like DHF and DSS can be predicted by the presence of clinical and biochemical factors like signs of bleeding, deranged liver function test, presence of urinary red blood cells and urinary protein; so that the patients at high risk for complication be identified early and started on treatment timely. CONCLUSION: Predictors of severe dengue are identified in this study but further large scale multi-centered studies are needed for better interpretation.