Clinical study on the efficacy of hepatitis B vaccination in hepatitis C virus related chronic liver diseases in Egypt.

BACKGROUND: Chronic hepatitis B (HBV) and C virus (HCV) infections represent significant public health issues internationally. HBV vaccination has high sero-conversion rates in patients with mild to moderate chronic liver disease but has reduced efficacy in advanced stages. AIM: to evaluate the efficacy of hepatitis B vaccination in HCV-related chronic liver disease and identify possible factors that may contribute to hypo-responsiveness in those patients. METHODS: Our study was a retrospective observational clinical study carried out at the tropical medicine department. It was conducted on 500 individuals (400 chronic HCV patients and 100 healthy controls). Individuals were divided into 5 groups: A (control group), B (cirrhotic patient not receiving treatment), C (chronic hepatitis patients receiving treatment), D (cirrhotic patients receiving treatment), and E (HCC patients receiving treatment). All individuals were subjected for comprehensive history taking, clinical examination, laboratory investigations, and assessment of anti-HBs titer. RESULTS: There is an inverse relationship between the level of anti-HBs Abs and the duration of vaccine. Diabetes and presence of cirrhosis have statistically significant relationship with serum anti-HBs Abs titer (P = 0.007). Oral DAAs therapy is associated with reduced response to HBV vaccine (only 31.75% of the patients were protected). CONCLUSION: HCV infection and its complications significantly impair HBV vaccine response. Levels of anti-HBs Abs decline progressively with increasing duration from the last dose in immunization schedule of HBV vaccine. Diabetes and presence of cirrhosis being the main risk factors for vaccine hypo-responsiveness, also oral DAAs therapy is associated with reduced response to HBV vaccine.

Triple-stage Quadrupole Mass Spectrometer to Determine Ubiquitously Present Per- and Polyfluorinated Alkyl Substances in Drinking Water at Part Per Trillion Levels Using Solid Phase Extraction Approach.

An accurate analytical method was developed to determine selected per- and polyfluorinated alkyl substances (PFAS) at the level of parts per trillion (ppt or ng/L) in drinking water. The method included a concentration step using solid phase extraction (SPE) approach in combination with a liquid chromatography-tandem mass spectrometry system (LC-MS/MS). This method was optimized and validated for the common PFAS contaminants in drinking water. An initial demonstration of capability was established with an acceptable initial calibration, minimum reporting limit (MRL), limit of detection (LOD), initial demonstration of low system background, and initial demonstration of precision (IDP). Isotopically labeled internal standards were used for quantification. Surrogate standards were used to monitor method performance. The current method will help in better understanding of PFAS crisis by providing an efficient measurement of PFAS in water. In this study, the recoveries of four surrogates were between 84 and 113%, and calculated limit of detection (DL) and minimum reporting limits (MRL) were generally 1.0-3.0 and 5-10 ng/L, respectively.

A Preliminary Toxicology Study on Eco-friendly Control Target of Spodoptera frugiperda.

Pyrethroid and indoxacarb are commonly used pesticides to control the fall armyworm (Spodoptera frugiperda) in the crops. There are a series of consequences caused by the use of pyrethroid and indoxacarb pesticides under emergency control, such as pest resistance development, contamination of soil, water, and farm products. This study analyzed the structure and physiological function of the sodium channel in S. frugiperda, which is an important step to elaborate the resistance mechanism of S. frugiperda to indoxacarb and pyrethroid pesticides. According to genetic analysis, the cloned cDNA sequences of sodium channel in S. frugiperda (SfNav) showed the shortest genetic distance with that of the sodium channel in Helicoverpa armigera. Under the induction of three pesticides, the expression of SfNav decreased in the first 12 h and then increased after 24 h. It was concluded that SfNav had a typical structure of the sodium channel of insects and its down-regulated expression can decrease the combination of S. frugiperda with pyrethroid and indoxacarb pesticides. The up-regulated expression of SfNav was conducive to the enhancement of the pesticide resistance.

Efficacy of antiviral therapy in patients with post-hepatitis C liver cirrhosis: is hyperuricaemia a potential adverse effect?

Hepatitis C virus (HCV) related liver cirrhosis is considered a major health problem; sofosbuvir (SOF)/ledipasvir (LDV) and SOF/daclatsvir (DACLA) are very promising direct antiviral agents (DAAS) especially in treating HCV genotype 4 which is the main genotype in Egypt. Uric acid elevation was reported in many systemic diseases and might be elevated during direct antiviral therapy. The aim is to evaluate efficacy and safety of SOF/LDV and SOF/DACLA plus ribavirin in treating HCV related child A liver cirrhosis and assess hyperuricaemia as a potential adverse effect to this regimen. METHODS: This prospective observatinal study included 128 HCV naive child A cirrhotic patients divided into two groups (77 patients were treated with SOF 400 mg, DACLA 60 mg and ribavirin 600 mg and 51 patients were treated with SOF 400 mg, LDV 90 mg and ribavirin 600 mg) for 12 weeks, during the treatment complete blood count, creatinine, bilirubin, alanine transaminase, aspartate transaminase and serum uric acid were monitored, HCV RNA quantitative PCR at 12 weeks after the end of treatment was done. RESULTS: Response to treatment in SOF/LDV (sof/led) group is about (98%), response to treatment in SOF/DACLA (sof/dacla) group is about (96%). Hyperuricaemia was noticed in 17.6% of patients received sof/led and in 15.5% of those received sof/dacla. CONCLUSION: SOF+LDV and SOF+DACLA plus ribavirin regimens are highly effective in treating chronic HCV patients with compensated liver cirrhosis. Hyperuricaemia is considered a potential adverse effect to DAAS containing ribavirin and may lead to serious side effects such as renal impairment.

Detection of hepatitis C virus core antigen as an alternative method for diagnosis of hepatitis C virus infection in blood donors negative for hepatitis C virus antibody.

BACKGROUND: Screening of blood donors in many countries is based on the use of serologic assays to detect specific anti-HCV antibodies (HCV Ab), but it lacks detection sensitivity. So, HCV RNA detection using the current gold standard real-time PCR is a must to rule out HCV infection with the main disadvantage being of high cost. HCV core antigen (HCV-c-Ag) immunoassay is proposed as a more cost efficient alternative to HCV RNA detection with PCR. AIM: To evaluate the effectiveness of HCV-c-Ag detection as a cheap alternative to HCV RNA (PCR) in diagnosis of HCV infection in blood donors who are HCV Ab negative. METHODS AND RESULTS: One hundred eighty-six volunteer blood donors who tested negative for HCV Ab were examined for HCV-c-Ag. Seven cases out of these 186 cases were HCV-c-Ag positive (4%). HCV RNA detection (PCR technique) was done to 30 cases (seven cases who test positive for HCV-c-Ag and 23 cases who test negative). Six out of the seven cases who were HCV-c-Ag positive (86%) were HCV RNA positive. Twenty-two cases out of the 23 cases who were HCV-c-Ag negative (96%) were HCV RNA negative. CONCLUSION: HCV-c-Ag detection is an efficient method for diagnosis of HCV infection during screening of blood donors with high specificity (95.6%) and high negative predictive value (95.6%).

Buprofezin dissipation and safety assessment in open field cabbage and cauliflower using GC/ITMS employing an analyte protectant.

An analytical method for the determination of buprofezin residues in cabbage and cauliflower was developed and validated using gas chromatography with ion trap mass spectrometry. The analyte protectant d-sorbitol was used at a concentration level of 0.5 mg mL-1 in acetonitrile instead of in matrix for constructing the calibration curves of the buprofezin standard. The average recoveries ranged from 91.3 to 96.8%, with an RSD of ≤2.7%. The limits of detection and quantitation of the method in cabbage and cauliflower were 1.3, 1.7 and 4.3, 6.2 µg kg-1 , respectively. The residual levels and dissipation kinetics of buprofezin 25% wettabe powder in cabbage and cauliflower cultivated under open field conditions was investigated at the single (T1) and double (T2) recommended rates of application. Half-life periods were found to be 1.73 and 2.1 days in cabbage, whereas in cauliflower, these values were 1.85 and 2.36 days at T1 and T2, respectively. Based on the dissipation study, and the maximum residue limit value of 0.05 mg kg-1 , the proposed pre-harvest interval of buprofezin in cabbage was 3-6 days and that in cauliflower was 4-10 days. The results showed that buprofezin is safe for application at both recommended application rates.

Validation of QuEChERS based method for determination of fenitrothion residues in tomatoes by gas chromatography-flame photometric detector: Decline pattern and risk assessment.

A simple and rapid gas chromatography with flame photometric detector (GC-FPD) determination method was developed to detect residue levels and investigate the dissipation pattern and safe use of fenitrothion in tomatoes. A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) using an ethyl acetate-based extraction, followed by a dispersive solid-phase extraction (d-SPE) with primary-secondary amine (PSA) and graphite carbon black (GCB) for clean up, was applied prior to GC-FPD analysis. The method showed satisfactory linearity, recovery and precision. The limits of detection (LOD) and quantification (LOQ) were 0.005 and 0.01mg/kg, respectively. The residue levels of fenitrothion were best described by first order kinetics with a half-life of 2.2days in tomatoes. The potential health risks posed by fenitrothion were not significant, based on supervised residue trial data. The current findings could provide guidance for safe and reasonable use of fenitrothion in tomatoes and prevent health problems to consumers.

Safety assessment of chromafenozide residue level with decline study on tomato in Egypt.

The objective of this study is to perform a safety assessment of chromafenozide residue level on tomato at the Egyptian national level. An open field decline study of chromafenozide on tomato was performed. The theoretical maximum daily intake (TMDI) of chromafenozide was calculated for assessing the chronic dietary exposure indicating that the ADI value of chromafenozide (0.27 mg/kg bw/day) was not exceeded. As a result, the safety assessment of chromafenozide residue levels was attained. A validated method of the QuEChERS approach followed by HPLC-DAD analysis was used to determine the chromafenozide residues. The recoveries ranged from 70 to 88% with relative standard deviations ranging from 2.0 to 9.0%. The limit of quantitation was 0.01 mg/kg. The half-life of chromafenozide on tomatoes was 3.5 days.

Validation of quantitative method for azoxystrobin residues in green beans and peas.

This study presents a method validation for extraction and quantitative analysis of azoxystrobin residues in green beans and peas using HPLC-UV and the results confirmed by GC-MS. The employed method involved initial extraction with acetonitrile after the addition of salts (magnesium sulfate and sodium chloride), followed by a cleanup step by activated neutral carbon. Validation parameters; linearity, matrix effect, LOQ, specificity, trueness and repeatability precision were attained. The spiking levels for the trueness and the precision experiments were (0.1, 0.5, 3 mg/kg). For HPLC-UV analysis, mean recoveries ranged between 83.69% to 91.58% and 81.99% to 107.85% for green beans and peas, respectively. For GC-MS analysis, mean recoveries ranged from 76.29% to 94.56% and 80.77% to 100.91% for green beans and peas, respectively. According to these results, the method has been proven to be efficient for extraction and determination of azoxystrobin residues in green beans and peas.