Light-induced reversible reorganizations in closed Type II reaction centre complexes: physiological roles and physical mechanisms.

The purpose of this review is to outline our understanding of the nature, mechanism and physiological significance of light-induced reversible reorganizations in closed Type II reaction centre (RC) complexes. In the so-called 'closed' state, purple bacterial RC (bRC) and photosystem II (PSII) RC complexes are incapable of generating additional stable charge separation. Yet, upon continued excitation they display well-discernible changes in their photophysical and photochemical parameters. Substantial stabilization of their charge-separated states has been thoroughly documented-uncovering light-induced reorganizations in closed RCs and revealing their physiological importance in gradually optimizing the operation of the photosynthetic machinery during the dark-to-light transition. A range of subtle light-induced conformational changes has indeed been detected experimentally in different laboratories using different bRC and PSII-containing preparations. In general, the presently available data strongly suggest similar structural dynamics of closed bRC and PSII RC complexes, and similar physical mechanisms, in which dielectric relaxation processes and structural memory effects of proteins are proposed to play important roles.

Relation of Obesity with Breast Cancer among the Patients Attending at National Institute of Cancer Research & Hospital.

Breast cancer among women is gradually increasing in Bangladesh day by day. A number of breast cancer related etiological factors identified as age, reproductive factors, menarche, menopausal status, life style, hormone replacement therapy, genetics and alcohol intake. Obesity is an important factor for developing breast cancer in different countries. Obesity is one of the modifiable factors. The aim of the study was to find out the factors which might be associated with obesity among female breast cancer patients in Bangladesh. It was a case-control study conducted at the Department of Medical Oncology, National Institute of Cancer Research & Hospital (NICRH), Dhaka, Bangladesh from August 2014 to July 2015. Ninety one case and equal numbers of age matched controls were included in the study. The mean age of the case was 42.99 (±9.24) years and that of the control was 44.11±8.97 years. Majority of patients i.e. 59.3% (n=54) in case group was in pre-menopausal state where as 52.7% (n=48) of respondents in control group were in menopausal state. Increased waist to hip ratio (>0.85) was associated with increased risk of breast cancer (OR: 8.1). This was also true for increased BMI of ≥25kg/m² (OR: 4.57), increased waist circumference (OR: 3.52) and ever OCP use (OR: 2.11). However, para >3, education and moderate to heavy work were found to be protective against breast cancer (OR: <1). In clinical setting waist-to-hip ratio, body mass index (BMI) and waist circumference (WC) can be used effectively to identify women with an increased risk of breast cancer.

Evaluating feasibility and acceptability of a group WHO trans-diagnostic intervention for women with common mental disorders in rural Pakistan: a cluster randomised controlled feasibility trial.

AIMS: The aim of this feasibility trial was to evaluate the feasibility and acceptability of the locally adapted Group Problem Management Plus (PM+) intervention for women in the conflict affected settings in Swat, Pakistan. METHODS: This mixed-methods study incorporated a quantitative component consisting of a two arm cluster randomised controlled feasibility trial, and qualitative evaluation of the acceptability of the Group PM+ to a range of stakeholder groups. For the quantitative component, on average from each of the 20 Lady Health Workers (LHWs) catchment area (20 clusters), six women were screened and recruited for the trial with score of >2 on the General Health Questionnaire and score of >16 on the WHO Disability Assessment Schedule. These LHW clusters were randomised on a 1 : 1 allocation ratio using a computer-based software through a simple randomisation method to the Group PM+ intervention or Enhanced Usual Care. The Group PM+ intervention consisted of five weekly sessions of 2 h duration delivered by local non-specialist females under supervision. The primary outcome was individual psychological distress, measured by levels of anxiety and depression on the Hospital Anxiety and Depression Scale at 7th week after baseline. Secondary outcomes include symptoms of depression, post-traumatic stress disorder (PTSD), general psychological profile, levels of functioning and generalised psychological distress. Intervention acceptability was explored through in-depth interviews. RESULTS: The results show that lay-helpers with no prior mental health experience can be trained to achieve the desired competency to successfully deliver the intervention in community settings under supervision. There was a good intervention uptake, with Group PM+ considered useful by participants, their families and lay-helpers. The outcome evaluation, which was not based on a large enough study to identify statistically significant results, indicated statistically significant improvements in depression, anxiety, general psychological profile and functioning. The PTSD symptoms and depressive disorder scores showed a trend in favour of the intervention. CONCLUSION: This trial showed robust acceptance in the local settings with delivery by non-specialists under supervision by local trained females. The trial paves the way for further adaptation and exploration of the outcomes through larger-scale implementation and definitive randomised controlled trials in the local settings.

WHO Parents Skills Training (PST) programme for children with developmental disorders and delays delivered by Family Volunteers in rural Pakistan: study protocol for effectiveness implementation hybrid cluster randomized controlled trial.

BACKGROUND: Development disorders and delays are recognised as a public health priority and included in the WHO mental health gap action programme (mhGAP). Parents Skills Training (PST) is recommended as a key intervention for such conditions under the WHO mhGAP intervention guide. However, sustainable and scalable delivery of such evidence based interventions remains a challenge. This study aims to evaluate the effectiveness and scaled-up implementation of locally adapted WHO PST programme delivered by family volunteers in rural Pakistan. METHODS: The study is a two arm single-blind effectiveness implementation-hybrid cluster randomised controlled trial. WHO PST programme will be delivered by 'family volunteers' to the caregivers of children with developmental disorders and delays in community-based settings. The intervention consists of the WHO PST along with the WHO mhGAP intervention for developmental disorders adapted for delivery using the android application on a tablet device. A total of 540 parent-child dyads will be recruited from 30 clusters. The primary outcome is child's functioning, measured by WHO Disability Assessment Schedule - child version (WHODAS-Child) at 6 months post intervention. Secondary outcomes include children's social communication and joint engagement with their caregiver, social emotional well-being, parental health related quality of life, family empowerment and stigmatizing experiences. Mixed method will be used to collect data on implementation outcomes. Trial has been retrospectively registered at ClinicalTrials.gov (NCT02792894). DISCUSSION: This study addresses implementation challenges in the real world by incorporating evidence-based intervention strategies with social, technological and business innovations. If proven effective, the study will contribute to scaled-up implementation of evidence-based packages for public mental health in low resource settings. TRIAL REGISTRATION: Registered with ClinicalTrials.gov as Family Networks (FaNs) for Children with Developmental Disorders and Delays. Identifier: NCT02792894 Registered on 6 July 2016.

Maslinic acid protects against isoproterenol-induced cardiotoxicity in albino Wistar rats.

The present study aimed to evaluate the protective effect of maslinic acid (MA) on body weight, heart weight, lipids, lipoproteins, lipid peroxidation (LPO), cardiac marker enzymes, and paraoxonase (PON) in normal control and isoproterenol (ISO)-induced myocardial infarcted albino Wistar rats. After treatment with MA (15 mg/kg) for 7 days, myocardial infarction was induced by subcutaneous injection of ISO (85 mg/kg) for two consecutive days. ISO caused a considerable decrease in body weight and increased the heart weight. The concentrations of total cholesterol, triglycerides, very low-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol were higher, whereas that of high-density lipoprotein-cholesterol was lower, in the serum of ISO-administered rats. The activities of the cardiac marker enzymes creatine kinase, alanine transaminase, aspartate transaminase, and γ-glutamyl transferase and levels of malondialdehyde were elevated in the serum of ISO-treated rats. ISO-administered rats also exhibited a decline in the activity of PON. Pretreatment of rats with MA reduced the effects of ISO on all parameters tested. This is the first report of the protective effect of MA on ISO-induced cardiotoxicity and of an association between PON status and MA supplementation. The observed cardioprotective effects may be due to the antihyperlipidemic potential of MA, inhibition of LPO, and antioxidant activity.

Smoking restrictions in the home and secondhand smoke exposure among primary schoolchildren before and after introduction of the Scottish smoke-free legislation.

OBJECTIVE: To examine change in home smoking restrictions one year after introduction of Scottish smoke-free legislation, and whether type of restriction impacts upon secondhand smoke (SHS) exposure among children. DESIGN: Comparison of nationally representative, cross-sectional, class-based surveys carried out in the same schools before and after legislation. PARTICIPANTS: 2527 primary schoolchildren (aged around 11 years) surveyed in January 2006 and 2379 in January 2007. OUTCOME MEASURES: Self-reported home smoking restrictions, salivary cotinine concentrations. RESULTS: Children surveyed after implementation of legislation were more likely than those surveyed before its introduction to report complete home smoking restrictions as opposed to partial (relative risk ratio (partial vs complete) 0.75 (95% CI 0.63 to 0.89) or no restrictions (RR (no restrictions vs complete) 0.50 (0.40 to 0.63). Children living with smokers were less likely to have stringent restrictions in place compared with children living with non-smokers (for both vs neither parents smoke: RR (partial vs complete) 18.29 (13.26 to 25.22) and RR (no restrictions vs complete) 104.73 (70.61 to 155.33). Among smoking households, restriction type varied according to the number and gender of parents who smoke. In both smoking and non-smoking households, children's SHS exposure was directly related to type of home smoking restriction, with lowest exposures among those reporting complete restrictions. CONCLUSION: This study has shown an increase in the proportion of children reporting a complete ban on smoking in their household after the introduction of smoke-free legislation and supports growing evidence of the wider impact smoke-free legislation can have on smoker behaviour. However, quitting smoking combined with complete home smoking bans will still afford children the best protection from SHS exposure.

Role of nitric oxide in alcohol-induced changes in lipid profile of moderate and heavy alcoholics.

Biochemical changes in plasma and red cell membrane in moderate and heavy alcoholics were investigated to compare them with teetotalers in the present study. Significant changes in lipid, lipoprotein profile, and lipid peroxidation were evident from the study suggesting the cardioprotective effect in moderate alcoholics, and adverse changes leading to cardiovascular risk in heavy alcoholics. Both nitrite and nitrate levels in plasma of moderate alcoholics increased significantly when compared with teetotalers and the increase is more pronounced in heavy alcoholics. The results of the present study showed no significant difference in osmotic hemolysis in red cells from moderate and heavy alcoholics incubated with NaCl at concentrations ranging from 0.1% to 0.9%. Further, the study showed a possible relationship of nitric oxide (NO) with changes in plasma lipid profile. To sum up, these changes in both moderate and heavy alcoholics clearly indicated the involvement of NO in rendering tolerance to alcohol-induced effects and also in modulation of alcohol effects.

Partition controlled delivery of hydrophobic substances in toxicity tests using poly(dimethylsiloxane) (PDMS) films.

Interpretation of toxicity test results may be hampered when doubt exists about the actual exposure concentration. Processes that are responsible for differences between the nominal and the actual concentration in aqueous test systems may include sorption, precipitation, volatilization, chemical and biological degradation, and uptake into biological or test tissue. In this study, the use of a poly(dimethylsiloxane) (PDMS) film containing the test compound is introduced as a versatile technique for partition controlled delivery of hydrophobic compounds to aqueous toxicity tests. Two methods developed produced preloaded films, having toxicant added to the PDMS prepolymer solution before film deposition and curing, and postloaded films, which are created by the addition of toxicant in a solvent to an already-polymerized PDMS film. Preloaded films were generally more easily prepared, may better accommodate larger molecules, and have a higher capacity than postloaded films. Postloaded films provided film-solution partition coefficients with higher precision and allowed for the use of films from stock and thus for a more portable technique. Chemical analysis showed that equilibrium between films and the aqueous solution was established within 7-10 min and was maintained for a suite of aromatic compounds (log Kow ranging from 2.8 to 6.1). The reliability of the film technique was demonstrated by application to the Microtox bacterial toxicity tests of solutions of polycyclic aromatic hydrocarbons (PAHs).

Plasmodium falciparum and hepatitis E virus co-infection in fulminant hepatic failure.

Acute hepatitis E and falciparum malaria can each present with fulminant hepatic failure and are common in tropical countries. However, co-existence of these two conditions has not been reported. We report a 20-year-old girl who presented with fever and altered sensorium. Peripheral smear was positive for Plasmodium falciparum, and IgM anti-HEV was positive. She died despite antimalarial drugs and supportive management. Postmortem liver tissue showed changes suggestive of acute viral hepatitis.

Complete sequence of the IncPbeta plasmid R751: implications for evolution and organisation of the IncP backbone.

The broad host range IncP plasmids are of particular interest because of their ability to promote gene spread between diverse bacterial species. To facilitate study of these plasmids we have compiled the complete sequence of the IncPbeta plasmid R751. Comparison with the sequence of the IncPalpha plasmids confirms the conservation of the IncP backbone of replication, conjugative transfer and stable inheritance functions between the two branches of this family. As in the IncPalpha genome the DNA of this backbone appears to have been enriched for the GCCG/CGGC motifs characteristic of the genome of organisms with a high G+C content, such as P. aeruginosa, suggesting that IncPbeta plasmids have been subjected during their evolution to similar mutational and selective forces as IncPalpha plasmids and may have evolved in pseudomonad hosts. The IncP genome is consistently interrupted by insertion of phenotypic markers and/or transposable elements between oriV and trfA and between the tra and trb operons. The R751 genome reveals a family of repeated sequences in these regions which may form the basis of a hot spot for insertion of foreign DNA. Sequence analysis of the cryptic transposon Tn4321 revealed that it is not a member of the Tn21 family as we had proposed previously from an inspection of its ends. Rather it is a composite transposon defined by inverted repeats of a 1347 bp IS element belonging to a recently discovered family which is distributed throughout the prokaryotes. The central unique region of Tn4321 encodes two predicted proteins, one of which is a regulatory protein while the other is presumably responsible for an as yet unidentified phenotype. The most striking feature of the IncPalpha plasmids, the global regulation of replication and transfer by the KorA and KorB proteins encoded in the central control operon, is conserved between the two plasmids although there appear to be significant differences in the specificity of repressor-operator interactions. The importance of these global regulatory circuits is emphasised by the observation that the operator sequences for KorB are highly conserved even in contexts where the surrounding region, either a protein coding or intergenic sequence, has diverged considerably. There appears to be no equivalent of the parABCDE region which in the IncPalpha plasmids provides multimer resolution, lethality to plasmid-free segregants and active partitioning functions. However, we found that the continuous sector from co-ordinate 0 to 9100 bp, encoding the co-regulated klc and kle operons as well as the central control region, could confer a high degree of segregational stability on a low copy number test vector. Thus R751 appears to exhibit very clearly what was first revealed by study of the IncPalpha plasmids, namely a fully functional co-ordinately regulated set of replication, transfer and stable inheritance functions.

Role of atrial ischaemia in development of atrial fibrillation following coronary artery bypass surgery.

OBJECTIVE: Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting (CABG) operations, occurring in 5 to 40% of cases. A number of studies have implicated atrial ischaemia in the genesis of this arrhythmia. The aim of this study was to examine the relationship between atrial coronary anatomy and the incidence of post operative atrial fibrillation. METHOD: To investigate a possible anatomical explanation to the onset of AF after CABG, 25 patients with documented AF after CABG were matched and compared to 25 patients which remained in sinus rhythm (SR). All coronary angiograms were reported blindly by a cardiac radiologist with reference to the blood supply of the sino-atrial (SA) node and atrio-ventricular (AV) node before and after surgery. RESULTS: Univariate analysis of risk factors did not identify any significant difference (Fisher exact test, P > 0.05) between the two groups in age, gender, left ventricular function, ischaemic time, number of vessels diseased or grafted, renal dysfunction and withdrawal of beta-blockade. However, significant disease in the SA nodal artery was present in 2 patients of the SR group when compared to 9 in the AF group. Significant disease of AV nodal artery was present in only 4 patients of the SR group when compared to 18 in the AF group. Comparison between the two groups showed a significantly increased incidence of SA or AV nodal artery disease in the AF group, (SA: P = 0.018, AV: P = 0.0001). Mean hospital stay was 8.1 days for the SR group and 9.1 days in the AF group (P = 0.175). CONCLUSION: Obstructive disease in the SA nodal and AV nodal arteries is more common in patients developing atrial fibrillation following coronary artery bypass surgery than those who remain in sinus rhythm. If the incidence of AF could be predicted by the anatomical distribution of arterial disease then targeting prophylaxis to this group may be possible.