Isolation, purification and characterization of phytase from Bacillus subtilis MJA

In this study, three strains of bacteria were isolated from soil. Among the three isolated strains, one was identified morphologically and confirmed by the molecular techniques as Bacillus subtilis MJA with high phytase activity. The phytase-producing bacteria were isolated using phytate screening agar media (PSM) with only 1.5% glucose and 0.5% sodium phytate as only source for carbon. In order to optimize the phytase production by B. subtilis MJA, different factors were studied. A combination of 0.5% glucose and 0.5% sucrose showed to be the best carbon source. Also, malt extract used as a source of nitrogen gave the highest phytase production. Also, the maximum phytase production was detected after incubation for four days (720 U/ml) at an optimum pH value of 7. The produced phytase was purified through various chromatographic techniques. The estimated enzyme molecular mass was about 38 kDa and the phytase had an optimal temperature and pH of 37°C and 5 to 6, respectively. On the other hand, studying the enzyme stability showed that enzyme was stable at low temperature, and had good pH stability by retaining 80% of its initial activity over a wide range of pH from 2 to 8. Kinetic values of Vmax and Km for the purified enzyme were 510 U/mg and 0.485 mM, respectively. The phytase activity was affected by different divalent metal ions. Cations such as Cu2+ or Fe2+ showed an inhibition effect on the phytase activity and the effect was in a dose dependent manner while, cations such as Mg2+ or Ca2+ showed an increase in the phytase activity. On the other hand, among different matricesused to immobilize the cells for phytase production, agar-agar matrix indicated a promising immobilization matrix used for phytase production by B. subtilis MJA.Keywords: Phytase, microbial sources, optimization, purification, characterization, immobilizationAfrican Journal of BiotechnologyVol. 12(20), pp. 2957-296

The dilemma of widal test - which brand to use? a study of four different widal brands: a cross sectional comparative study

<p>Abstract</p> <p>Background</p> <p>Serodiagnosis of typhoid fever by Widal test based on demonstrating the presence of agglutinins (antibodies) in the serum of an infected patient, against the H (flagellar) and O (somatic) antigens of <it>Salmonella enterica </it>serotype Typhi has been associated with many debates. This is why the aim of this study was to: (i) Compare the diagnostic accuracy of four different commercial kits used to perform Widal test (Remel, BioSystems, Dialab and Biotec). (ii) Compare the sensitivity and specificity of both anti-O and anti-H antibodies. (iii) Compare the validity of single versus paired serum samples with a rising titer for the diagnosis of typhoid fever.</p> <p>Methods</p> <p>Duplicate serum samples were obtained from150 patients clinically diagnosed as typhoid fever patients. Moreover, single serum samples were obtained from 25 patients with febrile diseases other than typhoid fever. All samples were tested using the four different Widal brands and <it>Salmonella </it>Typhi IgM anti-LPS ELISA</p> <p>Results</p> <p><b>-</b>The results of Widal tests differed markedly using the four Widal brands in terms of sensitivity and specificity at three cut-off values of 1/80, 1/160 and 1/320. Remel brand gave the highest sensitivities and the lowest specificities and Dialab brand gave the highest specificities and the lowest sensitivities for both anti-O and anti-H antibodies at the three cut-off values.</p> <p><b>-</b>Four fold rise in the antibodies titer was not demonstrable among clinically diagnosed typhoid fever patients</p> <p>-H agglutinins were less sensitive and less specific than O agglutinins</p> <p>Conclusions</p> <p>-Widal test results showed marked discrepancies using different Widal brands. None of the serum samples of the typhoid fever patients showed four fold rise in the antibody titers. Raised O agglutinins were of slightly greater diagnostic value than raised H agglutinins.</p> <p>Significance and impact of study</p> <p>Widal test done sequentially using two brands could be of value in typhoid fever diagnosis. Single serum sample could be used for typhoid fever diagnosis relying on anti O titer.</p

Oxidative stress pattern in hepatitis C patients co-infected with schistosomiasis

This study was designed to investigate the role of hepatitis C virus (HCV)-induced oxidative stress in the pathogenesis of the disease with the measurement of tumor necrosis factor (TNF-∝) and super oxide dismutase (SOD). Eighty patients from Hepatology Unit, Faculty of Medicine, Ain Shams University, were investigated. Thirty patients with bilharzial HCV and 30 patients with non-bilharzial HCV as compared to 20 healthy controls of the same age and sex ratio were investigated. The concentrations of liver enzymes [glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), alkaline phosphatase (ALP)], bilirubin (Bil), albumin (Alb) and total protein (TP) as well as TNF-α and Mn-SOD were determined. The mean level of the different liver function tests in the three groups in the study showed that the levels of GOT, GPT and ALP were significantly higher in the HCV groups as compared to the control group (p &lt; 0.05). While serum bilirubin, albumin and total protein were non-significantly decreased in the HCV groups as compared to the control group (p &gt; 0.05). Furthermore, the mean level of TNF-α was significantly higher in the HCV groups as compared to the control group (p &lt; 0.001) and SOD was significantly decreased in the HCV groups as compared to the control group (p &lt; 0.001). There is a cause-effect relationship between increased levels of TNF-α and decreased levels of SOD, relative to progression of chronic HCV, especially with bilharzias co-infection. Supporting the view that oxidative damage plays a role in chronic HCV infection, also TNF-α establishes a positive auto regulatory loop that can amplify the inflammatory response and lead to chronic inflammation. More evidence indicates that HCV block apoptosis and prolong survival of the host cell in order to gain time for replication and increase viral progeny production.Key words: Hepatitis C virus, tumor necrosis factor-alpha, superoxide dismutase, oxidative stress, schistosomiasis

Hepcidin and its Related Hematological Biomarkers of Anemia in Children on Hemodialysis: Role of Carnitine Deficiency

BACKGROUND: Anemia is one of the most common complications in end-stage renal disease (ESRD) patients. Hepcidin is a hormone that regulates iron homeostasis in patients with ESRD. Carnitine deficiency is commonly seen in hemodialysis (HD) patients. AIM: This study aimed to investigate the relationship between hepcidin and inflammatory and other anemia markers in children with ESRD and to evaluate the association of carnitine deficiency with anemia in these patients. SUBJECTS AND METHODS: Thirty pediatric patients with ESRD undergoing HD, and thirty healthy, age- and sex-matched children served as controls were included in the study. Serum levels hepcidin, iron status, high-sensitivity C-reactive protein, and total carnitine were measured. RESULTS: Statistically significant increases in serum levels of hepcidin (100.7 ± 0.99 ng\ml vs. 77.43 ± 0.8 ng\ml, p = 0.000), was found in HD children as compared to healthy controls. Statistically significant increase in serum levels of hs-CRP (3.94 ± 0.19 mg/l vs. 1.36 ± 0.07 mg/l, p = 0.04) was found in HD children as compared to healthy controls. However, serum levels of carnitine (29.59 ± 2.46 μmol/L vs. 36 ± 2.39 μmol/L, p = 0.000) showed statistically significant decreases in HD children as compared to healthy controls positive correlation was found between hepcidin and hs-CRP (r = 0.059, p = 0.042). Furthermore, a positive correlation was present between serum carnitine levels and serum iron levels (r = 0.651, p = 0.042). CONCLUSION: Serum hepcidin may be a more useful biomarker of functional iron deficiency in children on HD. The efficacy of carnitine treatment for children on HD with carnitine deficiency and its effect on anemia needs to be studied

A method for comparing the impact on carcinogenicity of tobacco products : a case study on heated tobacco versus cigarettes

This work was funded by the Netherlands Food and Consumer Product Safety Authority (NVWA), Utrecht, The Netherlands.Comparing the harmful health effects related to two different tobacco products by applying common risk assessment methods to each individual compound is problematic. We developed a method that circumvents some of these problems by focusing on the change in cumulative exposure (CCE) of the compounds emitted by the two products considered. The method consists of six steps. The first three steps encompass dose‐response analysis of cancer data, resulting in relative potency factors with confidence intervals. The fourth step evaluates emission data, resulting in confidence intervals for the expected emission of each compound. The fifth step calculates the change in CCE, probabilistically, resulting in an uncertainty range for the CCE. The sixth step estimates the associated health impact by combining the CCE with relevant dose‐response information. As an illustrative case study, we applied the method to eight carcinogens occurring both in the emissions of heated tobacco products (HTPs), a novel class of tobacco products, and tobacco smoke. The CCE was estimated to be 10‐ to 25‐fold lower when using HTPs instead of cigarettes. Such a change indicates a substantially smaller reduction in expected life span, based on available dose‐response information in smokers. However, this is a preliminary conclusion, as only eight carcinogens were considered so far. Furthermore, an unfavorable health impact related to HTPs remains as compared to complete abstinence. Our method results in useful information that may help policy makers in better understanding the potential health impact of new tobacco and related products. A similar approach can be used to compare the carcinogenicity of other mixtures.Publisher PDFPeer reviewe

Novel implementation strategy to electronically screen and signpost patients to health behavior apps: Mixed methods implementation study (OptiMine study)

BACKGROUND: Behavior change apps have the potential to provide individual support on a population scale at low cost, but they face numerous barriers to implementation. Electronic health records (EHRs) in acute care hospitals provide a valuable resource for identifying patients at risk, who may benefit from behavior change apps. A novel, emerging implementation strategy is to use digital technologies not only for providing support to help-seeking individuals but also for signposting patients at risk to support services (also called proactive referral in the United States). OBJECTIVE: The OptiMine study aimed to increase the reach of behavior change apps by implementing electronic signposting for smoking cessation and alcohol reduction in a large, at-risk population that was identified through an acute care hospital EHR. METHODS: This 3-phase, mixed methods implementation study assessed the acceptability, feasibility, and reach of electronic signposting to behavior change apps by using a hospital\u27s EHR system to identify patients who are at risk. Phase 1 explored the acceptability of the implementation strategy among the patients and staff through focus groups. Phase 2 investigated the feasibility of using the hospital EHR to identify patients with target risk behaviors and contact them via SMS text message, email, or patient portal. Phase 3 assessed the impact of SMS text messages sent to patients who were identified as smokers or risky drinkers, which signposted them to behavior change apps. The primary outcome was the proportion of participants who clicked on the embedded link in the SMS text message to access information about the apps. The acceptability of the SMS text messages among the patients who had received them was also explored in a web-based survey. RESULTS: Our electronic signposting strategy-using SMS text messages to promote health behavior change apps to patients at risk-was found to be acceptable and feasible and had good reach. The hospital sent 1526 SMS text messages, signposting patients to either the National Health Service Smokefree or Drink Free Days apps. A total of 13.56% (207/1526) of the patients clicked on the embedded link to the apps, which exceeded our 5% a priori success criterion. Patients and staff contributed to the SMS text message content and delivery approach, which were perceived as acceptable before and after the delivery of the SMS text messages. The feasibility of the SMS text message format was determined and the target population was identified by mining the EHR. CONCLUSIONS: The OptiMine study demonstrated the proof of concept for this novel implementation strategy, which used SMS text messages to signpost at-risk individuals to behavior change apps at scale. The level of reach exceeded our a priori success criterion in a non-help-seeking population of patients receiving unsolicited SMS text messages, disconnected from hospital visits. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/23669

The OptiMine feasibility study: a novel implementation strategy to electronically screen and signpost patients to health behaviour apps

Background: Behavior change apps have the potential to provide individual support on a population scale at low cost, but they face numerous barriers to implementation. Electronic health records (EHRs) in acute care hospitals provide a valuable resource for identifying patients at risk, who may benefit from behavior change apps. A novel, emerging implementation strategy is to use digital technologies not only for providing support to help-seeking individuals but also for signposting patients at risk to support services (also called proactive referral in the United States). Objective: The OptiMine study aimed to increase the reach of behavior change apps by implementing electronic signposting for smoking cessation and alcohol reduction in a large, at-risk population that was identified through an acute care hospital EHR. Methods: This 3-phase, mixed methods implementation study assessed the acceptability, feasibility, and reach of electronic signposting to behavior change apps by using a hospital’s EHR system to identify patients who are at risk. Phase 1 explored the acceptability of the implementation strategy among the patients and staff through focus groups. Phase 2 investigated the feasibility of using the hospital EHR to identify patients with target risk behaviors and contact them via SMS text message, email, or patient portal. Phase 3 assessed the impact of SMS text messages sent to patients who were identified as smokers or risky drinkers, which signposted them to behavior change apps. The primary outcome was the proportion of participants who clicked on the embedded link in the SMS text message to access information about the apps. The acceptability of the SMS text messages among the patients who had received them was also explored in a web-based survey. Results: Our electronic signposting strategy—using SMS text messages to promote health behavior change apps to patients at risk—was found to be acceptable and feasible and had good reach. The hospital sent 1526 SMS text messages, signposting patients to either the National Health Service Smokefree or Drink Free Days apps. A total of 13.56% (207/1526) of the patients clicked on the embedded link to the apps, which exceeded our 5% a priori success criterion. Patients and staff contributed to the SMS text message content and delivery approach, which were perceived as acceptable before and after the delivery of the SMS text messages. The feasibility of the SMS text message format was determined and the target population was identified by mining the EHR. Conclusions: The OptiMine study demonstrated the proof of concept for this novel implementation strategy, which used SMS text messages to signpost at-risk individuals to behavior change apps at scale. The level of reach exceeded our a priori success criterion in a non–help-seeking population of patients receiving unsolicited SMS text messages, disconnected from hospital visits. International Registered Report Identifier (IRRID): RR2-10.2196/2366

Mining electronic health records to promote the reach of digital interventions for cancer prevention through proactive electronic outreach:Protocol for the mixed methods OptiMine study

BACKGROUND: Digital behavior change interventions have demonstrated effectiveness for smoking cessation and reducing alcohol intake, which ultimately reduce cancer risk. Leveraging electronic health records (EHR) to identify at-risk patients and increasing the reach of digital interventions through proactive electronic outreach provide a novel approach that may increase the number of individuals who engage with evidence-based treatment. OBJECTIVE: This study aims to increase the reach of digital behavior change interventions by implementing a proactive electronic message system for smoking cessation and alcohol reduction among a large, at-risk population identified through an acute hospital EHR. METHODS: This protocol describes a 3-phase, mixed-methods implementation study to assess the acceptability, feasibility, and reach of a proactive electronic message system to digital interventions using a hospital's EHR system to identify eligible patients. In Phase 1, we will conduct focus group discussions with patients and hospital staff to assess the overall acceptability of the electronic message system. In Phase 2, we will conduct a descriptive analysis of the patient population in the hospital EHR regarding target risk behaviors and other person-level characteristics to determine the project's feasibility and potential reach. In Phase 3, we will send proactive messages to patients identified as smokers or risky drinkers. Messages will encourage and provide access to behavior change mobile apps via an embedded link; the primary outcome will be the proportion of participants who click on the link to access information about the apps. RESULTS: At the time of initial protocol submission, data collection was complete, but analysis had not begun. This study was funded by Cancer Research UK from April 2019 to March 2020. Health Research Authority approval was granted in June 2019. CONCLUSIONS: Increasing the reach of digital behavior change interventions can improve population health by reducing the burden of preventable death and disease. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/23669

Predictors of Serum 25-Hydroxyvitamin D Concentrations among a Sample of Egyptian Schoolchildren

Objective. To assess the level of 25-hydroxyvitamin D status among a sample of Egyptian schoolchildren and to evaluate predictors of deficiency and insufficiency. Subjects and Methods. A cross-sectional study comprising 200 prepubescent schoolchildren aged from 9 to 11 years was performed. A questionnaire including frequency of midday sun exposure, milk intake, physical activity, and level of maternal education was taken. Body mass index (BMI) was calculated; serum 25-hydroxyvitamin D [25(OH)D], serum calcium, phosphorus, and parathyroid hormone were measured. Results. Vitamin D deficiency [serum 25(OH)D < 20 ng/mL] was detected in 11.5% of subjects while its insufficiency (serum 25(OH)D is between 20 and 29.9 ng/mL) was detected in 15%. Results revealed that obesity, low physical activity, low sun exposure, and low maternal education level are significant predictors of insufficiency, though female gender, low maternal education level, and low milk intake are significant predictors of deficiency. Lower serum phosphorus and higher serum parathyroid hormone were significantly associated with both deficiency and insufficiency (p<0.05). Conclusion. Vitamin D deficiency and insufficiency are common among schoolchildren in Egypt. Food fortification, vitamin D supplementation, and increasing maternal awareness about the importance of physical activity and exposure of their children to ultraviolet light may help to overcome this problem