Effects of melatonin on bone: a case control study

Background: There is a stereotypical notion of estrogen being the most relevant parameter for bone health in post-menopausal females, but apart from estrogen; advances in research have presented ample evidence that melatonin may also play a critical role in bone health outcomes.Methods: Our study consisted of 48 post-menopausal females, 24 subjects in the case group and 24 in control groups, to study the differences of certain parameters existing between the two. Serum Melatonin was calculated using ELISA test and Bone Mineral Density (BMD) was evaluated using a portable Ultrasound Bone Densitometer Testing Machine.Results: A strong Positive Pearson correlation exists between BMD and serum melatonin levels. Pearson correlation coefficient value (r) of 0.96 and 0.95 for the Control and Osteopenic group respectively. Linear regression for control group is (r2) 0.92. Linear regression for osteopenic group is (r2) 0.90.Conclusions: The results of our study exhibited strong interdependence between the serum melatonin levels and their effects on BMD. Osteopenic subjects who had a lower BMD were also found to have relatively lower levels of serum melatonin. Aligning with the results, similarly control group with normal BMD was found to have relatively higher level of serum melatonin

Conventional and Molecular Typing of Salmonella enterica serotype Typhi Locally Isolated In Baghdad

Phenotypic And genotypic characteristics of Salmonella enterica serotype Typhi have been determined for 29 isolates, from Baghdad in 2007. Conventional typing methods were performed by biochemical tests, and antimicrobial susceptibility test. Molecular typing performed by analysis plasmid DNA beside using the Random Amplified Polymorphic DNA (RAPD-PCR). For the latter, two universal primers that have selected for the high discriminatory power were used for RAPD analysis. All isolates were belong one biotype according to the differention by their ability to decarboxylat lysine, 29(100%) were lysine (+). All the isolates were susceptible to the Antibiotics used. However, all the strains free of plasmids. RAPD was capable of grouping the strains in 6 genotypic patterns using primer 784, in 4 genotypic patterns using primer 787. Conventional phenotypic typing methods, as well as the DNA plasmid analysis, presented non significant discriminatory power; however, RAPD-PCR analysis showed discriminatory power, reproducibility, easy interpretation and can be considered as a promising alternative typing method for S. Typhi

Numerical Simulation of Heat Transfer Enhancement in the Presence of an Electric Field at Low Reynolds Numbers

One way for optimization of the rational use of energy in thermal systems is to increase their rate of heat transfer. In this study, the effects of an electric field on the fluid flow and temperature field as an active method of enhancement is numerically investigated. The hydrodynamics and heat transfer behaviors of laminar duct flow with specific boundary conditions in the presence of an EHD actuator was taken into consideration. The partial difference equations of flow field and electric field namely continuity, momentum and energy equations for fluid flow and electric current and Poisson’s equations for electric field was numerically solved with finite volume method. At first, the electric equations were solved and then their results were imported to the fluid field for improvement of the body forces. The aim of this study is an application of the EHD actuator on local heat transfer enhancement by using wire-plate electrodes in laminar duct flow. The obtained results show for the flows with R

Mutations of rpob Gene Associated with Rifampin Resistance among Mycobacterium Tuberculosis Isolated in Tuberculosis Regional Reference Laboratory in Northeast of Iran during 2015-2016

Background: Drug resistance is a leading concern in control of TB. Resistance against rifampin as one of the most important drugs in the treatment of Mycobacterium tuberculosis is caused by mutations in the 81-base pair region of the rpoB gene encoding the β-subunit of RNA polymerase. This study aimed to characterize the mutations in the rpoB gene associated with rifampin resistance among M. tuberculosis. Methods: This study was conducted on referred samples of patients who did not respond to anti-TB treatment, in Tuberculosis Regional Reference Laboratory at Shariati Hospital. Drug susceptibility of M. tuberculosis isolates was surveyed using a proportional method on LJ medium. The isolates with resistant to rifampin were reconfirmed and then the rpoB gene was amplified and sequenced. Results: Among 27 resistant cases, 8, 11 and 8 people were from Iran, Afghanistan, and Turkmenistan, respectively. In 26 out of 27 isolates, rpoB gene mutations were observed. The most prevalent mutations belonged to the codon 53. The most prevalent mutations belonged to the TCG (Ser) 531TTG (leu) with prevalence 51.8 (n=14), and GAC (Asp)516TAC (Tyr), CAC (His) 526GAC (Asp) and CAC (His) 526TAC(Tyr) mutations with prevalence 14.8(n=4). Twenty-three isolates had just one mutation. Conclusion: The use of rpoB gene sequencing led to the lack of the need for growth of the organism in the culture medium, the direct use of clinical samples, reduction of biological risks and a detection about 96.3 of MDR TB cases lowering the cost of the treatment

Antibacterial Activity of Small Molecules Which Eradicate Methicillin-Resistant Staphylococcus aureus Persisters

The serious challenge posed by multidrug-resistant bacterial infections with concomitant treatment failure and high mortality rates presents an urgent threat to the global health. We herein report the discovery of a new class of potent antimicrobial compounds that are highly effective against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The compounds were efficiently synthesized in one-pot employing a cascade of Groebke-Blackburn-Bienayme and aza-Michael addition reactions. Phenotypic screening of the pilot library against various bacterial species including methicillin-sensitive and MRSA strains, has identified potent chemotypes with minimal inhibitory concentrations (MIC) of 3.125-6.25 mu g/ml. The most potent compounds were fast-acting at eradicating exponentially growing MRSA, with killing achieved after 30 min of exposure to the compounds. They were also able to kill MRSA persister cells which are tolerant to most available medications. Microscopic analysis using fluorescence microscope and atomic force microscope indicate that these compounds lead to disruption of bacterial cell envelopes. Most notably, bacterial resistance toward these compounds was not observed after 20 serial passages in stark contrast to the significant resistance developed rapidly upon exposure to a clinically relevant antibiotic. Furthermore, the compounds did not induce significant hemolysis to human red blood cells. In vivo safety studies revealed a high safety profile of these motifs. These small molecules hold a promise for further studies and development as new antibacterial agents against MRSA infections.This work was supported by the generous grants from the IsDB-Transformers Fund and the Research Funding Department, University of Sharjah, UAE (CoV19-0306)

Evaluation of systematic assessment of asthma-like symptoms and tobacco smoke exposure in early childhood by well-child professionals: A randomised trial

Objectives: This study aimed to evaluate the effectiveness of systematic assessment of asthma-like symptoms and environmental tobacco smoke (ETS) exposure during regular preventive well-child visits between age 1 and 4 years by wellchild professionals. Methods: Sixteen well-child centres in Rotterdam, the Netherlands, were randomised into 8 centres where the brief assessment form regarding asthma-like symptoms and ETS exposure was used and 8 centres that applied usual care. 3596 and 4179 children (born between April 2002 and January 2006) and their parents visited the intervention and control centres, respectively. At child's age 6 years, physician-diagnosed asthma ever, wheezing, fractional exhaled nitric oxide (FeNO), airway resistance (Rint), health-related quality of life (HRQOL) and ETS exposure at home ever were measured. Linear mixed models were applied. Results: No differences in asthma, wheezing, FeNO, Rint or HRQOL measurements between intervention and control group were found using multilevel regression in an intention-to-treat analysis (p>0.05). Children of whom the parents were interviewed by using the brief assessment form at the intervention well-child centres had a decreased risk on ETS exposure at home ever, compared to children who

Antimicrobial activity of nature-inspired molecules against multidrug-resistant bacteria

Multidrug-resistant bacterial infections present a serious challenge to global health. In addition to the spread of antibiotic resistance, some bacteria can form persister cells which are tolerant to most antibiotics and can lead to treatment failure or relapse. In the present work, we report the discovery of a new class of small molecules with potent antimicrobial activity against Gram-positive bacteria and moderate activity against Gram-negative drug-resistant bacterial pathogens. The lead compound SIMR 2404 had a minimal inhibitory concentration (MIC) of 2 μg/mL against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-intermediate Staphylococcus aureus (VISA). The MIC values against Gram-negative bacteria such as Escherichia coli and Actinobacteria baumannii were between 8–32 μg/mL. Time-kill experiments show that compound SIMR 2404 can rapidly kill tested bacteria. Compound SIMR 2404 was also found to rapidly kill MRSA persisters which display high levels of tolerance to conventional antibiotics. In antibiotic evolution experiments, MRSA quickly developed resistance to ciprofloxacin but failed to develop resistance to compound SIMR 2404 even after 24 serial passages. Compound SIMR 2404 was not toxic to normal human fibroblast at a concentration of 4 μg/mL which is twice the MIC concentration against MRSA. However, at a concentration of 8 μg/mL or higher, it showed cytotoxic activity indicating that it is not ideal as a candidate against Gram-negative bacteria. The acceptable toxicity profile and rapid antibacterial activity against MRSA highlight the potential of these molecules for further studies as anti-MRSA agents

Evaluation of systematic assessment of asthma-like symptoms and tobacco smoke exposure in early childhood by well-child professionals: A randomized trial

Asthma is a highly prevalent chronic condition associated with considerable morbidity, reduced health-related quality of life (HRQOL) and significant costs for public health [1], [2]. Interventions aimed at preventing childhood asthma are being developed and evaluated [3]-[9]. While the majority of asthma management education for parents occurs in the clinical setting, increasingly, multifaceted environmental interventions to decrease asthma-like symptoms are delivered by community health workers [7]. Previous studies identified positive outcomes associated with community health worker-delivered interventions, including decreased asthmalike symptoms [7]