Structure-based drug design of DNA minor groove binders and evaluation of their antibacterial and anticancer properties

Antimicrobial and chemotherapy resistance are escalating medical problem of paramount importance. Yet, research for novel antimicrobial and anticancer agents remains lagging behind. With their reported medical applications, DNA minor groove binders (MGBs) are worthy of exploration. In this study, the approach of structure-based drug design was implemented to generate 11 MGB compounds including a novel class of bioactive alkyne-linked MGBs. The NCI screening protocol was utilized to evaluate the antitumor activity of the target MGBs. Furthermore, a variety of bactericidal, cytopathogenicity, MIC90, and cytotoxicity assays were carried out using these MGBs against 6 medically relevant bacteria: Salmonella enterica, Escherichia coli, Serratia marcescens, Bacillus cereus, Streptococcus pneumoniae and Streptococcus pyogenes. Moreover, molecular docking, molecular dynamic simulations, DNA melting, and isothermal titration calorimetry (ITC) analyses were utilized to explore the binding mode and interactions between the most potent MGBs and the DNA duplex d(CGACTAGTCG)2. NCI results showed that alkyne-linked MGBs (26 & 28) displayed the most significant growth inhibition among the NCI-60 panel. In addition, compounds MGB3, MGB4, MGB28, and MGB32 showed significant bactericidal effects, inhibited B. cereus and S. enterica-mediated cytopathogenicity, and exhibited low cytotoxicity. MGB28 and MGB32 demonstrated significant inhibition of S. pyogenes, whereas MGB28 notably inhibited S. marcescens and all four minor groove binders significantly inhibited B. cereus. The ability of these compounds to bind with DNA and distort its groove dimensions provides the molecular basis for the allosteric perturbation of proteins-DNA interactions by MGBs. This study shed light on the mechanism of action of MGBs and revealed the important structural features for their antitumor and antibacterial activities, which are important to guide future development of MGB derivatives as novel antibacterial and anticancer agents.

Self-assembled micelles loaded with itraconazole as anti-Acanthamoeba nano-formulation

Acanthamoeba castellanii are opportunistic pathogens known to cause infection of the central nervous system termed: granulomatous amoebic encephalitis, that mostly effects immunocompromised individuals, and a sight threatening keratitis, known as Acanthamoeba keratitis, which mostly affects contact lens wearers. The current treatment available is problematic, and is toxic. Herein, an amphiphilic star polymer with AB2 miktoarms [A = hydrophobic poly(ℇ-Caprolacton) and B = hydrophilic poly (ethylene glycol)] was synthesized by ring opening polymerization and CuI catalyzed azide-alkyne cycloaddition. Characterization by 1H and 13C NMR spectroscopy, size-exclusion chromatography and fluorescence spectroscopy was accomplished. The hydrophobic drug itraconazole (ITZ) was incorporated in self-assembled micellar structure of AB2 miktoarms through co-solvent evaporation. The properties of ITZ loaded (ITZ-PCL-PEG2) and blank micelles (PCL-PEG2) were investigated through zeta sizer, scanning electron microscopy and Fourier-transform infrared spectroscopy. Itraconazole alone (ITZ), polymer (DPB-PCL), empty polymeric micelles (PCL-PEG2) alone, and itraconazole loaded in polymeric micelles (ITZ-PCL-PEG2) were tested for anti-amoebic potential against Acanthamoeba, and the cytotoxicity on human cells were determined. The polymer was able to self-assemble in aqueous conditions and exhibited low value for critical micelle concentration (CMC) 0.05-0.06 µg/mL. The maximum entrapment efficiency of ITZ was 68%. Of note, ITZ, DPB, PCL-PEG2 and ITZ-PCL-PEG2 inhibited amoebae trophozoites by 37.34%, 36.30%, 35.77%, and 68.24%, respectively, as compared to controls. Moreover, ITZ-PCL-PEG2 revealed limited cytotoxicity against human keratinocyte cells. These results are indicative that ITZ-PCL-PEG2 micelle show significantly better anti-amoebic effects as compared to ITZ alone and thus should be investigated further in vivo to determine its clinical potential.

Serum multi-omics analysis in hindlimb unloading mice model: Insights into systemic molecular changes and potential diagnostic and therapeutic biomarkers

Microgravity, in space travel and prolonged bed rest conditions, induces cardiovascular deconditioning along with skeletal muscle mass loss and weakness. The findings of microgravity research may also aid in the understanding and treatment of human health conditions on Earth such as muscle atrophy, and cardiovascular diseases. Due to the paucity of biomarkers and the unknown underlying mechanisms of cardiovascular and skeletal muscle deconditioning in these environments, there are insufficient diagnostic and preventative measures. In this study, we employed hindlimb unloading (HU) mouse model, which mimics astronauts in space and bedridden patients, to first evaluate cardiovascular and skeletal muscle function, followed by proteomics and metabolomics LC-MS/MS-based analysis using serum samples. Three weeks of unloading caused changes in the function of the cardiovascular system in c57/Bl6 mice, as seen by a decrease in mean arterial pressure and heart weight. Unloading for three weeks also changed skeletal muscle function, causing a loss in grip strength in HU mice and atrophy of skeletal muscle indicated by a reduction in muscle mass. These modifications were partially reversed by a two-week recovery period of reloading condition, emphasizing the significance of the recovery process. Proteomics analysis revealed 12 dysregulated proteins among the groups, such as phospholipid transfer protein, Carbonic anhydrase 3, Parvalbumin alpha, Major urinary protein 20 (Mup20), Thrombospondin-1, and Apolipoprotein C-IV. On the other hand, metabolomics analysis showed altered metabolites among the groups such as inosine, hypoxanthine, xanthosine, sphinganine, l-valine, 3,4-Dihydroxyphenylglycol, and l-Glutamic acid. The joint data analysis revealed that HU conditions mainly impacted pathways such as ABC transporters, complement and coagulation cascades, nitrogen metabolism, and purine metabolism. Overall, our results indicate that microgravity environment induces significant alterations in the function, proteins, and metabolites of these mice. These observations suggest the potential utilization of these proteins and metabolites as novel biomarkers for assessing and mitigating cardiovascular and skeletal muscle deconditioning associated with such conditions.

An impactful prospective study on pulmonary tuberculosis in geriatric populations besides its clinical outcomes and implications in the Indian subcontinent

OBJECTIVE

Geriatric populations are most at risk for the tuberculosis pandemic, and as people age, the rate of infection rises steadily and drastically. Geriatric individuals frequently experience diagnostic challenges with a wide range of comorbidities, but employing all available standard and novel methods to diagnose any infection is crucial. The prophylactic and therapeutic management for the geriatric population presents a significant difficulty and challenge in assessing an appropriate and effective therapeutic outcome due to prolonged drug therapy and adverse drug reactions. The present study aims to determine the prevalence of tuberculosis in the geriatric population in the Indian subcontinent, its risk factors, clinical outcomes, and adherence to the medication.

PATIENTS AND METHODS

A prospective observational investigation was conducted in a tertiary care Hospital in Erode, Tamil Nadu, India, from April 2021 to September 2022. A total of 1,014 patients were screened, and 176 participants were selected. The participants were then subjected to medication adherence evaluation, and clinical data was collected.  The statistical analysis was performed using SPSS version 20.0.

RESULTS

Among 176 participants, 135 (76.70%) were old (65-74 age), 37 (21.02%) were very old (75-84 age) TB patients, and 4 (2.27%) patients were extremely old TB patients (>85). Medication adherence was improved from baseline to the end of the study (p≤0.000). 110 patients completed the treatment (62.5%). 41 patients were cured in between treatments (23.29%), 13 patients died during the treatment (7.38%), 9 patients lost their follow-up (5.11%), 3 patients failed to respond to the treatment (1.70%).

CONCLUSIONS

The effectiveness of therapy critically depends on the patient's medication adherence to anti-TB therapy. In addition to having a higher likelihood of therapy failure, elderly patients did not appropriately respond to the treatment and completely recovered from the infection even after effective pharmacotherapy.

Assessment of Serum Homocysteine Level to Predict Early Prognosis of Ischaemic Stroke

Cerebrovascular disease is the third most familiar cause of mortality worldwide and in Bangladesh. The reported prevalence of stroke in Bangladesh is 0.3%. Age, high serum glucose, elevated admission blood pressure, fever, large infarction size, and hyperhomocysteinemia has been reported to be risk factor for early post-stroke neurological deterioration. Early serum homocysteine level estimation can predict the early prognosis of ischemic stroke. In a developing country like Bangladesh, an earlier stroke outcome prediction for guiding therapeutic approach is essential. This study aimed to specify the role of estimating serum homocysteine during the early phase of acute ischemic stroke to assume an early prognosis that would guide- a management plan, the need to stay in the hospital and the need for intervention. This cross-sectional descriptive study was performed at the Department of Medicine, Mymensingh Medical College Hospital, Bangladesh from October 2021 to April 2022. Radiologically confirmed all ischemic stroke patients admitted at the Department of Medicine, Mymensingh Medical College Hospital, during the study period fulfilling the inclusion and exclusion criteria were included in this study. Non-probability purposive sampling technique was used. Data was collected using a pre-designed case record form. Quantitative data were represented as mean and standard deviation and qualitative data as frequency and percentage. The comparison was made by Chi-square test and independent samples t-test using SPSS (version 26.0). During the study period, among 716 stroke patients, 59 ischemic stroke patients were included in this study. The mean age of the patients was 64.0±11.72 years. After 72 hours of supportive treatment, early neurological outcomes were observed using NIHSS scoring. Out of 59 patients, the condition of 45(76.0%) patients improved or remained stable (END-) and the state of 14(24.0%) patients worsened (END+). Elderly age-raised temperature and elevated blood glucose level are known to increase infarction size, but only elevated temperature (p value 0.009) has statistical significance in this study. The mean homocysteine level ±SD was 20.22±6.95μmol/L, which is above the normal (<15μmol/L). The level was above average for both outcome groups. Serum homocysteine level was significantly higher in END(+) group (31.59±2.98μmol/L) than END(-) group (16.69±2.66μmol/L) and p value was <0.001.

The study of healthcare professionals' perspective towards the quality of diabetic care services in Abha

OBJECTIVE

The aim of this study was to investigate the relationship between organizational characteristics and diabetes care from the perspective of health care professionals (HCPs) in Abha, Kingdom of Saudi Arabia.

SUBJECTS AND METHODS

A cross-sectional, self-reported survey of healthcare professionals was done. The study comprised a total of 106 HCPs from various departments involved with diabetes patient clinics or service providers. The electronic data collecting form was used to gather the data.

RESULTS

The study revealed a stronger association between the availability of bed facilities and better glycemic control. Moreover, the majority of HCPs believes that urbanization and sedentary lifestyles are the main contributors to the rise of diabetes mellitus in Saudi Arabia. Depending on organizational features, the regulations that are available for monitoring defaulter patients and running continuous medical education (CME) programs are vastly different. The main cause of the reported lack of medications for managing diabetic care was described as being a problem with the central medical supply store's drug supply, which was influenced by the type of health sector.

CONCLUSIONS

Facilitating change at all levels, including patient education, HCPs education, and organizational development, can improve the quality of treatment. The current study can provide insight into the focus of interventional strategies to deliver diabetes patients with high-quality patient care.

Knowledge, beliefs, and attitudes among general population towards bipolar disorders: a cross-sectional report from the Southern region of Saudi Arabia

OBJECTIVE

The aim of this study was to understand the impact of demographic characteristics and to describe the gender differences in knowledge, beliefs, and attitudes towards bipolar disorders among common residents in the Southern region of Saudi Arabia.

SUBJECTS AND METHODS

This cross-sectional survey was conducted between January 2021 and March 2021. The survey was conducted among the common residents in the southern region of the Kingdom of Saudi Arabia. The data were collected by using a structured, self-administered, validated questionnaire comprised of a dichotomous type of questions along with Likert scale.

RESULTS

There is a significant difference in the distribution of knowledge scores between male and female study participants (p=0.000). No significant gender differences have been identified in beliefs and attitudes toward bipolar disorder (p=0.229) and in overall score (p=0.159). The traumatic event was reported as the major cause of bipolar disorder. The age group and employment status were found to be the major predictor of knowledge, beliefs, and attitudes about bipolar disorder.

CONCLUSIONS

Although the knowledge awareness rate on bipolar disorder is high among public in the Southern region, there is a vast scope for improving it. Education should be disseminated to promote mental health awareness and improve attitudes and beliefs on bipolar disorders and reduce stigma and discrimination against patients with bipolar disorders.

Long-COVID, Metabolic and Endocrine Disease

In the aftermath of the corona pandemic, long-COVID or post-acute COVID-19 syndrome still represents a great challenge, and this topic will continue to represent a significant health problem in the coming years. At present, the impact of long-COVID on our health system cannot be fully assessed but according to current studies, up to 40% of people who have been infected with SARS-CoV-2 suffer from clinically relevant symptoms of long-COVID syndrome several weeks to months after the acute phase. The main symptoms are chronic fatigue, dyspnea, and various cognitive symptoms. Initial studies have shown that people with overweight and diabetes mellitus have a higher risk of developing long-COVID associated symptoms. Furthermore, repeated treatment of acute COVID-19 and long-COVID with steroids can contribute to long-term metabolic and endocrine disorders. Therefore, a structured program with rehabilitation and physical activity as well as optimal dietary management is of utmost importance, especially for patients with metabolic diseases and/or long-COVID. Furthermore, the removal of autoantibodies and specific therapeutic apheresis procedures could lead to a significant improvement in the symptoms of long-COVID in individual patients.

Role of oxidative stress in angiogenesis and the therapeutic potential of antioxidants in breast cancer

The escalation of cancer cases globally, especially breast cancer, is of concern. Angiogenesis is hallmark of cancer pathogenesis and plays an important role in cancer progression and metastasis. Pro-angiogenic agents, secreted by tumor cells, form new blood vessels, and produce reactive oxygen species (ROS). ROS promote angiogenesis via two major pathways: namely Vascular Endothelial Growth Factor (VEGF) dependent and non-VEGF dependent pathways. As a consequence of unbalanced ROS overproduction and low antioxidants levels, oxidative stress occurs and promotes angiogenesis in breast cancer tissues. Thus, the potential use of antioxidants as a preventive therapy in breast cancer. Preclinical studies depict that vitamins A and E may counter oxidative stress resulting in reduction of metastasis and viability of breast cancer. Furthermore, clinical studies demonstrate a decline in breast cancer risk in postmenopausal women upon the consumption of antioxidants. Herein, we discuss various pro-angiogenic agents that may play an important role in breast cancer angiogenesis. Moreover, the contribution of oxidative stress in inducing the angiogenic process is extensively reviewed here. Furthermore, the findings of pre-clinical and clinical studies on the use of antioxidants, namely vitamins A and E, in breast cancer are deliberated upon, along with the role of angiogenesis in cancer therapy.

Assessment of knowledge and practice of mammography and breast self-examination among the general female population in Asir region of KSA

OBJECTIVE

Breast cancer is the most common malignancy in Kingdom of Saudi Arabia (KSA) and an increasing burden in terms of incidence, morbidity and mortality. It accounts for about 28.7% of all new cancers in women. In 2015, the Saudi cancer registry shows that breast cancer was graded first among women and it accounts for 16.7% of all cancers reported among Saudi nationals. This study was designed to assess breast cancer screening knowledge and practices among women in the Asir region, Kingdom of Saudi Arabia.

MATERIALS AND METHODS

A cross-sectional study recruiting 1,021 female participants was performed. The variables included breast cancer knowledge, socio-demographic features, breast self-examination knowledge and practice. Descriptive statistics was used to compare and analyze the collected data while chi-square test was used to check the statistical significance among the selected variables. Saudi married women from Asir region were the participants of this cross-sectional study.

RESULTS

Our findings suggested that participants had a satisfactory level of knowledge about breast self-examination and mammograms at a rate of > 90% and 44.76% respectively. Over 90% of participants had good breast self-exam knowledge, however, only 6.37% was always performed breast self-examination. Similarly, nearly 40% of participants performed mammograms, while 40.5% were unaware. Leaflets and doctors were the primary sources of information for participants regarding the information of breast cancer screening.

CONCLUSIONS

Breast self-examination is a crucial approach to the timely detection of breast cancer and is subsequently critical for effective treatment. From the findings of this study we concluded that most women in the Asir region have a good awareness of breast cancer screening methods. However, either screening of self-examination or mammogram for breast cancer was not carried out thoroughly and regularly. This means that we must continue to emphasize the importance of primary health care in the earliest stages of breast cancer.

Biodiversity of commercially important finfish species caught by mid-water and bottom trawls from two different coasts of Arabian Sea: Threats and conservation strategies

This study was conducted to estimate the diversity and the occurrence of commercially important finfish species collected by twenty fish sampling site of Sindh and Baluchistan coasts of the Arabian Sea in Pakistan from January to December 2019. Additionally, physicochemical characteristics of seawater were analyzed from these selected sites and found to be within suitable ranges required for fish growth and survive. A total of 81287 fish individuals were collected and identified as 49 species belonging to 26 families in our study. The most diversified family was Sparidae (13 species) followed by Carangidae and Lutjanidae (4 species), Mullidae, Serranidae, Ariidae (3 species), and Sciaenidae (2 species). The remaining 20 families were represented by only one species. The values of Shannon diversity index calculated for the four selected habitats revealed that high fish diversity was reported at Sonmiani Coast (H'=1.81), while less at Ormara Coast (H'=0.23). Likewise, Evenness index (E) was high at Sonmiani Coast (E=0.50) and less fish diversity was reported at Ormara Coast (E=0.06). Reducing risks to threatened marine species in coastal habitats also requires conservation actions at multiple scales. Thus, it was concluded that our study could be valuable in providing the more information's regarding to the diversity of finfish species and their occurrence along the Pakistan Coast. Further, to better understand the effects, regular monitoring and conservation measures should be taken to mitigate the influence of anthropogenic activities and protect finfish diversity from further decline.

Machine learning based decipherment of Cell Population Data: a promising hospital front-door screening tool for COVID-19

Introduction/Objective

Key challenges against early diagnosis of COVID-19 are its symptoms sharing nature and prolong SARS-CoV-2 PCR turnaround time. Hither machine learning (ML) tools experienced by routinely generated clinical data; potentially grant early prediction.

Methods/Case Report

Routine and earlier diagnostic data along demographic information were extracted for total of 21,672 subsequent presentations. Along conventional statistics, multilayer perceptron (MLP) and radial basis function (RBF) were applied to predict COVID-19 from pre-pandemic control. Three feature sets were prepared, and performance evaluated through stratified 10-fold cross validation. With differing predominance of COVID-19, multiple test sets were created and predictive efficiency was evaluated to simulate real-fashion performance against fluctuating course of pandemic. Models validation was also inducted in prospective manner on independent dataset, equating framework forecasting to conclusions from PCR.

Results (if a Case Study enter NA)

RBF model attained superior cross entropy error 20.761(7.883) and 20.782(3.991) for Q-Flags and Routine Items respectively while MLP outperformed for cell population data (CPD) parameters with value of 6.968(1.259) for ‘training(testing)’. Our CPD driven MLP framework in challenge of lower (<5%) COVID-19 predominance affords greater negative predictive values (NPV >99%). Higher accuracy (%correct 92.5) was offered during prospective validation using independent dataset. Sensitivity analysis advances illusive accuracy (%correct 94.1) and NPV (96.9%). LY-WZ, Blasts/Abn Lympho?, ‘HGB Interf?’, and ‘RBC Agglutination?’ are among novel enlightening study attributes.

Conclusion

CPD driven ML tools offer efficient screening of COVID-19 patients at presentation to hospital to backing early expulsion and directing patients’ flow-from amid the initial presentation to hospital.

Anticancer Properties of Asian Water Monitor Lizard (Varanus salvator), Python (Malayopython reticulatus) and Tortoise (Cuora kamaroma amboinensis)

BACKGROUND

Cancer contributes to significant morbidity and mortality despite advances in treatment and supportive care. There is a need for the identification of effective anticancer agents. Reptiles such as tortoise, python, and water monitor lizards are exposed to heavy metals, tolerate high levels of radiation, feed on rotten/germ-infested feed, thrive in unsanitary habitat and yet have prolonged lifespans. Such species are rarely reported to develop cancer, suggesting the presence of anticancer molecules/mechanisms.

METHODS

Here, we tested effects from sera of Asian water monitor lizard (Varanus salvator), python (Malayopython reticulatus) and tortoise (Cuora kamaroma amboinensis) against cancer cells. Sera were collected and cytotoxicity assays were performed using prostate cancer cells (PC3), Henrietta Lacks cervical adenocarcinoma cells (HeLa) and human breast adenocarcinoma cells (MCF7), as well as human keratinized skin cells (Hacat), by measuring lactate dehydrogenase release as an indicator for cell death. Growth inhibition assays were performed to determine the effects on cancer cell proliferation. Liquid chromatography mass spectrometry was performed for molecular identification.

RESULTS

The findings revealed that reptilian sera, but not bovine serum, abolished viability of Hela, PC3 and MCF7 cells. Samples were subjected to liquid chromatography mass spectrometry, which detected 57 molecules from V. salvator, 81 molecules from Malayopython reticulatus and 33 molecules from C. kamaroma amboinensis and putatively identified 9 molecules from V. salvator, 20 molecules from Malayopython reticulatus and 9 molecules from C. kamaroma amboinensis when matched against METLIN database. Based on peptide amino acid composition, binary profile, dipeptide composition and pseudo-amino acid composition, 123 potential Anticancer Peptides (ACPs) were identified from 883 peptides from V. salvator, 306 potential ACPs from 1074 peptides from Malayopython reticulatus and 235 potential ACPs from 885 peptides from C. kamaroma amboinensis.

CONCLUSION

To our knowledge, for the first time, we reported comprehensive analyses of selected reptiles' sera using liquid chromatography mass spectrometry, leading to the identification of potentially novel anticancer agents. We hope that the discovery of molecules from these animals will pave the way for the rational development of new anticancer agents.

Phosphorus supplementation modulates nitric oxide biosynthesis and stabilizes the defence system to improve arsenic stress tolerance in mustard

The interaction of mineral nutrients with metals/metalloids and signalling molecules is well known. In the present study, we investigated the effect of phosphorus (P) in mitigation of arsenic (As) stress in mustard (Brassica juncea L.). The study was conducted to investigate potential of 30 mg P·kg^-1 soil P supplement (diammonium phosphate) to cope up with the adverse effects of As stress (24 mg As·kg^-1 soil) in mustard plants Supplementation of P influenced nitric oxide (NO) generation, which up-regulated proline metabolism, ascorbate-glutathione system and glyoxalase system and alleviated the effects of on photosynthesis and growth. Arsenic stress generated ROS and methylglyoxal content was scavenged through P-mediated NO, and reduced As translocation from roots to leaves. The involvement of NO under P-mediated alleviation of As stress was substantiated with the use of cPTIO (NO biosynthesis inhibitor) and SNP (NO inducer). The reversal of P effects on photosynthesis under As stress with the use of cPTIO emphasized the role of P-mediated NO in mitigation of As stress and protection of photosynthesis The results suggested that P reversed As-induced oxidative stress by modulation of NO formation, which regulated antioxidant machinery. Thus, P-induced regulatory interaction between NO and reversal of As-induced oxidative stress for the protection of photosynthesis may be suggested for sustainable crops.

Gut microbiota of animals living in polluted environments are a potential resource of anticancer molecules

Cancer is a prominent cause of morbidity and mortality worldwide, in spite of advances in therapeutic interventions and supportive care. In 2018 alone, there were 18·1 million new cancer cases and 9·6 million deaths indicating the need for novel anticancer agents. Plant-based products have often been linked with protective effects against communicable and non-communicable diseases. Recently, we have shown that animals such as crocodiles thrive in polluted environments and are often exposed to carcinogenic agents, but still benefit from prolonged lifespan. The protective mechanisms shielding them from cancer could be attributed to the immune system, and/or it is possible that their gut microbiota produce anticancer molecules. In support, several lines of evidence suggest that gut microbiota plays a critical role in the physiology of its host. Here, we reviewed the available literature to assess whether the gut microbiota of animals thriving in polluted environment possess anticancer molecules.

Gut microbiome and human health under the space environment

The gut microbiome is well recognized to have a pivotal role in regulation of the health and behaviour of the host, affecting digestion, metabolism, immunity, and has been linked to changes in bones, muscles and the brain, to name a few. However, the impact of microgravity environment on gut bacteria is not well understood. In space environments, astronauts face several health issues including stress, high iron diet, radiation and being in a closed system during extended space missions. Herein, we discuss the role of gut bacteria in the space environment, in relation to factors such as microgravity, radiation and diet. Gut bacteria may exact their effects by synthesis of molecules, their absorption, and through physiological effects on the host. Moreover we deliberate the role of these challenges in the dysbiosis of the human microbiota and possible dysregulation of the immune system.

Identification of Antibacterial Molecule(s) from Animals Living in Polluted Environments

BACKGROUND

Snakes feed on germ-infested rodents, while water monitor lizards thrive on rotten matter in unhygienic conditions. We hypothesize that such creatures survive the assault of superbugs and are able to fend off disease by producing antimicrobial substances. In this study, we investigated the potential antibacterial activity of sera/lysates of animals living in polluted environments.

METHODS

Snake (Reticulatus malayanus), rats (Rattus rattus), water monitor lizard (Varanus salvator), frog (Lithobates catesbeianus), fish (Oreochromis mossambicus), chicken (Gallus gallus domesticus), and pigeon (Columba livia) were dissected and their organ lysates/sera were collected. Crude extracts were tested for bactericidal effects against neuropathogenic E. coli K1, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pyogenes, Pseudomonas aeruginosa, Bacillus cereus and Klebsiella pneumoniae. To determine whether lysates/sera protect human cells against bacterialmediated damage, cytotoxicity assays were performed by measuring lactate dehydrogenase release as an indicator of cell death. Lysates/sera were partially characterized using heat-treatment and pronasetreatment and peptide sequences were determined using the Liquid Chromatography Mass Spectrometry (LC-MS).

RESULTS

Snake and water monitor lizard sera exhibited potent broad-spectrum bactericidal effects against all bacteria tested. Heat inactivation and pronase-treatment inhibited bactericidal effects indicating that activity is heat-labile and pronase-sensitive suggesting that active molecules are proteinaceous in nature. LCMS analyses revealed the molecular identities of peptides.

CONCLUSION

The results revealed that python that feeds on germ-infested rodents and water monitor lizards that feed on rotten organic waste possess antibacterial activity in a heat-sensitive manner and several peptides were identified. We hope that the discovery of antibacterial activity in the sera of animals living in polluted environments will stimulate research in finding antibacterial agents from unusual sources as this has the potential for the development of novel strategies in the control of infectious diseases.

Sera/Organ Lysates of Selected Animals Living in Polluted Environments Exhibit Cytotoxicity against Cancer Cell Lines

Background:

Species of crocodiles and cockroaches can withstand high radiation, reside in unsanitary conditions, thrive on germ-infested feed, and are exposed to heavy metals, yet they are not reported to develop cancer. It has been postulated that such species have mechanisms to defend themselves against developing cancer. Here, selected species have been tested for potential cytotoxicity against selected cancer cell lines.

Methods:

In this study, various species of vertebrates and invertebrates were procured including Columba livia, Gallus gallus domesticus, Varanus salvator, Cuora kamamora amboinensis, Reticulatus malayanus, Oreochromis mossambicus, Rattus rattus, American bullfrog, Donax sp., Polymesoda coaxans, Tenebrio molitor, Lumbricus terrestris, Blatta lateralis, Grammostola rosea, and Penaeus monodon. Species were dissected and their organ lysates/sera/haemolymph were prepared. Cytotoxicity assays were performed using Prostate Cancer cells (PC3), Henrietta Lacks cervical adenocarcinoma cells (HeLa) and human breast adenocarcinoma cells (MCF7) as well as human keratinized skin cells (Hacat), by measuring lactate dehydrogenase release as an indicator for cell death. Growth inhibition assays were performed to determine the effects on cancer cell proliferation. Liquid Chromatography-Mass Spectrometry (LC-MS/MS) was performed for molecular identification.

Results:

The results revealed that body lysates of Polymesoda coaxans demonstrated more than 99% growth inhibition of all cancer cell lines tested but not on normal Hacat cells. More importantly, the serum of M. reticulatus abolished growth and produced cytotoxicity. Hence these samples were subjected to Liquid Chromatography- Mass Spectrometry (LC-MS/MS), which detected 81 small molecules and putatively identified 20 molecules when matched against the METLIN database. Out of 1094 peptides, 21 peptides were identified, while 1074 peptides were categorized as novel peptides. Based on properties such as peptide amino acid composition, binary profile, dipeptide composition and pseudo-amino acid composition, 306 potential peptides were identified.

Conclusion:

To our knowledge, here for the first time, we report a comprehensive analysis of sera exhibiting cytotoxicity against cancer cell lines tested and identified several molecules using LC-MS/MS.

Synthetic Dihydropyridines as Novel Antiacanthamoebic Agents

BACKGROUND

Acanthamoeba is an opportunistic pathogen widely spread in the environment. Acanthamoeba causes excruciating keratitis which can lead to blindness. The lack of effective drugs and its ability to form highly resistant cyst are one of the foremost limitations against successful prognosis. Current treatment involves mixture of drugs at high doses but still recurrence of infection can occur due to ineffectiveness of drugs against the cyst form. Pyridine and its natural and synthetic derivatives are potential chemotherapeutic agents due to their diverse biological activities.

OBJECTIVE

To study the antiamoebic effects of four novel synthetic dihydropyridine (DHP) compounds against Acanthamoeba castellanii belonging to the T4 genotype. Furthermore, to evaluate their activity against amoeba-mediated host cells cytopathogenicity as well as their cytotoxicity against human cells.

METHODS

Dihydropyridines were synthesized by cyclic dimerization of alkylidene malononitrile derivatives. Four analogues of functionally diverse DHPs were tested against Acanthamoeba castellanii by using amoebicidal, encystation and excystation assays. Moreover, Lactate dehydrogenase assays were carried out to study cytopathogenicity and cytotoxicity against human cells.

RESULTS

These compounds showed significant amoebicidal and cysticidal effects at 50 μM concentration, whereas, two of the DHP derivatives also significantly reduced Acanthamoebamediated host cell cytotoxicity. Moreover, these DHPs were found to have low cytotoxicity against human cells suggesting a good safety profile.

CONCLUSION

The results suggest that DHPs have potential against Acanthamoeba especially against the more resistant cyst stage and can be assessed further for drug development.

Molecular characterization of Orientia tsutsugamushi causing scrub typhus among febrile patients in north-central Bangladesh

Scrub typhus is a mite-borne rickettsial disease caused by Orientia tsutsugamushi, which is endemic in Asia Pacific region. In this study, infection rate and molecular epidemiologic traits of O. tsutsugamushi was investigated in Mymensingh, located in north-central Bangladesh. Among the blood samples from 453 febrile patients who visited Mymensingh medical college hospital in 2018, the 47 kDa protein gene of O. tsutsugamushi was detected in 78 samples (17.2%) by nested PCR. Phylogenetic analysis of the O. tsutsugamushi 56 kDa protein gene (18 samples) revealed a predominance of Karp-related genotype (89%), while the remaining belonged to Gilliam genotype. Samples of the Karp-related genotype mostly clustered with those of China, Taiwan, Thailand and India, etc., in emergent subgroups clades 2 and 4, which were distinct from clade 1, including prototype Karp strains. Among the 18 samples, three variable domains (VD) of 56 kDa type-specific antigen had different types of sequence diversity; VDI contained two or three repeats of eight amino acid units, while VDII and VDIII had amino acid substitution, deletion or insertion. The present study documented a potentially high prevalence of genetically diverse O. tsutsugamushi in north-central Bangladesh.

Spectral functions of one-dimensional systems with correlated disorder

We investigate the spectral function of Bloch states in a one-dimensional tight-binding non-interacting chain with two different models of static correlated disorder, at zero temperature. We report numerical calculations of the single-particle spectral function based on the Kernel polynomial method, which has an [Formula: see text] computational complexity. These results are then confirmed by analytical calculations, where precise conditions were obtained for the appearance of a classical limit in a single-band lattice system. Spatial correlations in the disordered potential give rise to non-perturbative spectral functions shaped as the probability distribution of the random on-site energies, even at low disorder strengths. In the case of disordered potentials with an algebraic power-spectrum, [Formula: see text] [Formula: see text], we show that the spectral function is not self-averaging for [Formula: see text].

Out-of-office blood pressure measurement for the diagnosis of hypertension in pregnancy: Survey of Canadian Obstetric Medicine and Maternal Fetal Medicine specialists

Background

Multiple hypertension guidelines recommend out-of-office measurements for the diagnosis of hypertension in non-pregnant adults, whereas pregnancy guidelines recommend in-office blood pressure measurements. The objective of our study was to determine how Canadian Obstetric Medicine and Maternal Fetal Medicine specialists measure blood pressure in pregnancy.

Methods

An email survey was sent to 69 Canadian Obstetric Medicine and Maternal Fetal Medicine specialists in academic centers across Canada to explore the practice patterns of blood pressure measurement in pregnant women.

Results

The response rate was 48%. The majority of respondents (63.6%) preferred office blood pressure measurement for diagnosing hypertension, but relied on home blood pressure readings for ongoing monitoring and management of hypertension during pregnancy (59.4%). The preferred method of out-of-office blood pressure measurement was home monitoring; 24-hour ambulatory blood pressure monitoring was not used due to limited availability and cost.

Conclusions

There is wide practice variation in methods of measuring blood pressure among Canadian specialists managing hypertension in pregnancy.

Adenoma Malignum of the Uterine Cervix: A Case Report

Adenoma malignum (AM) of the uterine cervix, otherwise known as minimal deviation adenocarcinoma, is a rare variant of cervical adenocarcinoma, which represents a diagnostic challenge, due to its benign-resembling histological characteristics. We present a case of 54-year-old nullipara woman presented with menorrhagia for 2 years and that had worsened over the past few months. Transabdominal ultrasound fibroid uterus with cluster of nabothian cysts was in the cervix. Subsequently MRI was done for better characterization and showed intramural myomas in the uterine body. A large ovoid mass containing multiple cystic components in the left side of cervix communicating with a tract to the cervical canal, which was consistent with features of adenoma malignum of the cervix. Then the differential diagnosis was included tunnel cluster nabothian cysts. The patient underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. The final histopathologic diagnosis revealed adenoma malignum of the cervix and intramural myomas. Subsequently, a review of literature was performed and the results demonstrated that early diagnosis, clinical stage and surgical protocols are the main factors affecting the prognosis of AM. Close follow-up of the cases may provide more information regarding this disease and the efficacy of the available therapeutic methods.

Gut bacteria of cockroaches are a potential source of antibacterial compound(s)

Here, we hypothesized that the microbial gut flora of animals/pests living in polluted environments, produce substances to thwart bacterial infections. The overall aim of this study was to source microbes inhabiting unusual environmental niches for potential antimicrobial activity. Two cockroach species, Gromphadorhina portentosa (Madagascar) and Blaptica dubia (Dubia) were selected. The gut bacteria from these species were isolated and grown in RPMI 1640 and conditioned media were prepared. Conditioned media were tested against a panel of Gram-positive (Methicillin-resistant Staphylococcus aureus, Streptococcus pyogenes, Bacillus cereus) and Gram-negative (Escherichia coli K1, Salmonella enterica, Serratia marcescens, Pseudomonas aeruginosa, Klebsiella pneumoniae) bacteria, as well as the protist pathogen, Acanthamoeba castellanii. The results revealed that the gut bacteria of cockroaches produce active molecule(s) with potent antibacterial properties, as well as exhibit antiamoebic effects. However, heat-inactivation at 95°C for 10 min had no effect on conditioned media-mediated antibacterial and antiamoebic properties. These results suggest that bacteria from novel sources i.e. from the cockroach's gut produce molecules with bactericidal as well as amoebicidal properties that can ultimately lead to the development of therapeutic drugs.

SIGNIFICANCE AND IMPACT OF THE STUDY

The bacteria isolated from unusual dwellings such as the cockroaches' gut are a useful source of antibacterial and antiamoebal molecules. These are remarkable findings that will open several avenues in our search for novel antimicrobials from unique sources. Furthermore studies will lead to the identification of molecules to develop future antibacterials from insects.

Escherichia coli K1 utilizes host macropinocytic pathways for invasion of brain microvascular endothelial cells

Eukaryotic cells utilize multiple endocytic pathways for specific uptake of ligands or molecules, and these pathways are commonly hijacked by pathogens to enable host cell invasion. Escherichia coli K1, a pathogenic bacterium that causes neonatal meningitis, invades the endothelium of the blood-brain barrier, but the entry route remains unclear. Here, we demonstrate that the bacteria trigger an actin-mediated uptake route, stimulating fluid phase uptake, membrane ruffling and macropinocytosis. The route of uptake requires intact lipid rafts as shown by cholesterol depletion. Using a variety of perturbants we demonstrate that small Rho GTPases and their downstream effectors have a significant effect on bacterial invasion. Furthermore, clathrin-mediated endocytosis appears to play an indirect role in E. coli K1 uptake. The data suggest that the bacteria effect a complex interplay between the Rho GTPases to increase their chances of uptake by macropinocytosis into human brain microvascular endothelial cells.

Effect of different levels of protein concentrates supplementation on the growth performance, plasma amino acids profile and mTOR cascade genes expression in early-weaned yak calves

Objective

This study evaluated the effects of different levels of protein concentrate supplementation on the growth performance of yak calves, and correlated the growth rate to changes occurring in the plasma- amino acids, -insulin profile, and signaling activity of mammalian target of rapamycin (mTOR) cascade to characterize the mechanism through which the protein synthesis can be improved in early weaned yaks.

Methods

For this study, 48 early (3 months old) weaned yak calves were selected, and assigned into four dietary treatments according to randomized complete block design. The four blocks were balanced for body weight and sex. The yaks were either grazed on natural pasture (control diet) in a single herd or the grazing yaks was supplemented with one of the three protein rich supplements containing low (17%; LP), medium (19%; MP), or high (21%; HP) levels of crude proteins for a period of 30 days.

Results

Results showed that the average daily gain of calves increased (0.14 vs 0.23–0.26 kg; p<0.05) with protein concentrates supplementation. The concentration of plasma methionine increased (p<0.05; 8.6 vs 10.1–12.4 μmol/L), while those of serine and tyrosine did not change (p>0.05) when the grazing calves were supplemented with protein concentrates. Compared to control diet, the insulin level of calves increased (p<0.05; 1.86 vs 2.16–2.54 μIU/mL) with supplementation of protein concentrates. Addition of protein concentrates up-regulated (p<0.05) expression of mTOR-raptor, mammalian vacuolar protein sorting 34 homolog, the translational regulators eukaryotic translation initiation factor 4E binding protein 1, and S6 kinase 1 genes in both Longissimus dorsi and semitendinosus. In contrast, the expression of sequestosome 1 was down-regulated in the concentrate supplemented calves.

Conclusion

Our results show that protein supplementation improves the growth performance of early weaned yak calves, and that plasma methionine and insulin concentrations were the key mediator for gene expression and protein deposition in the muscles.

Moringa oleifera-rich diet and T cell calcium signaling in spontaneously hypertensive rats

Moringa oleifera is a plant whose fruits, roots and leaves have been advocated for traditional medicinal uses. The physicochemical analysis shows that Moringa oleifera contains more dietary polyunsaturated fatty acids (PUFA) than saturated fatty acids (SFA). The consumption of an experimental diet enriched with Moringa oleifera extracts lowered blood pressure in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) rats as compared to rats fed an unsupplemented control diet. Anti-CD3-stimulated T cell proliferation was diminished in both strains of rats fed the Moringa oleifera. The experimental diet lowered secretion of interleukin-2 in SHR, but not in WKY rats compared with rats fed the control diet. Studies of platelets from patients with primary hypertension and from SHR support the notion that the concentration of intracellular free calcium [Ca(2+)](i) is modified in both clinical and experimental hypertension. We observed that the basal, [Ca(2+)](i) was lower in T cells of SHR than in those of WKY rats fed the control diet. Feeding the diet with Moringa oleifera extracts to WKY rats did not alter basal [Ca(2+)](i) in T cells but increased basal [Ca(2+)](i) in SHR. Our study clearly demonstrated that Moringa oleifera exerts antihypertensive effects by inhibiting the secretion of IL-2 and modulates T cell calcium signaling in hypertensive rats.

Magnetic Resonance Cholangiopancreatography (MRCP) Evaluation of Obstructive Jaundice in Comparison with Endoscopic Retrograde Cholangiopancreatography (ERCP)

This cross sectional study was carried out in the department of Radiology and Imaging in collaboration with Department of Gastroenterology of Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from July 2013 to June 2014 to evaluate the efficacy of Magnetic resonance cholangiopancreatography (MRCP) and ERCP in the management of obstructive jaundice and also to determine diagnostic validity accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MRCP in evaluation of obstructive jaundice. For this purpose, a total of 60 patients with obstructive jaundice who underwent MRCP and Endoscopic retrograde cholangiopancreatography (ERCP) in the above mentioned hospital were enrolled. More than one third (35.0%) patients were in 5th decade and the mean age was 46.2±12.9 years. Male female ratio was 1.1:1. Most (45.0%) of the patients had filling defect, 28.3% had concentric stenosis and 26.7% eccentric stenosis. In MRCP findings more than one third (35.0%) patients had choledocholithiasis followed by 26.7% had cholangiocarcinoma, 10.0% benign CBD stricture and 8.3% had ascariasis. In ERCP findings 31.7% patients had choledocholithiasis followed by 16.7% had cholangiocarcinoma, 13.3% benign CBD stricture and 10.0% ascariasis. All patients had increased serum bilirubin.

Moringa olifeira Lam. Stimulates Activation of the Insulin-Dependent Akt Pathway. Antidiabetic Effect in a Diet-Induced Obesity (DIO) Mouse Model

We investigated the antidiabetic effect of Moringa olifeira Lam. in a diet-induced obesity (DIO) mouse model. Six mice were randomly selected as normal controls. Moringa olifeira Lam. leaf extract at a dose of 200, 400 or 600 mg/kg body weight, glibenclamide (Glib) at the dose of 10 mg/kg (positive control) and distilled water at 10 ml/kg (control group) were administered orally by gastric intubation, and each group consisted of six mice. Insulinsensitive tissues (liver, skeletal muscle) were collected to investigate antidiabetic effects and examine the plant's molecular mechanisms. Moringa olifeira Lam. leaf extract prevented weight gain. It also reduced blood glucose in DIO mice. Glib and Moringa olifeira Lam. leaf extract, 400 mg/kg, treatments restored insulin levels towards normal values (P < 0.05 versus diabetic control group). Western immunoblot analysis of different tissues, collected at the end of the study, demonstrated that Moringa olifeira Lam. stimulated activation of the insulin-dependent Akt pathway and increased the protein content of Glut 4 in skeletal muscle. The improvement of hepatic steatosis observed in DIO-treated mice was associated with a decrease in the hepatic content of SREBP-1, a transcription factor involved in de novo lipogenesis. The hepatic PPARα protein content in the plant extract- treated mice remained significantly higher than those of the control group (P < 0.05). In conclusion, this study provides the first evidence for direct action of Moringa olifeira Lam. on pancreatic β-cells, enhancing glucose-stimulated insulin secretion. This correlated with hypoglycaemic effects in diabetic mice associated with restored levels of plasma insulin.

A New Model of Master of Philosophy in Physiological Sciences

The objectives of Master of Philosophy (MPhil) in Physiological Sciences are: 1) to describe the new ways in which anatomy, biochemistry and physiology on one hand, and microbiology, pathology and pharmacology on other hand meet their functional requirements through multidisciplinary integrated concepts; 2) to elucidate relationships between cell biology, molecular biology and molecular genetics by connecting dots of how cell functions are driven by molecules and being controlled by genes. This forms the basis of cell, molecular and genetics [CMG] module upon which 7 multidisciplinary modules of Physiological Sciences follow; 3) these 24 credit hours provide the physiological basis for PhD studies as well as faculty development to enhance learning abilities of medical student; 4) the modules constitute Cardio- Respiratory Physiological Sciences, GI and Renal Physiological Sciences, Neurosciences, Endo-Reproductive Physiological Sciences.; 5) it has integrated microbiology, pathology and pharmacology in a unique way through CMG of microbes leading to associated pathology and mechanisms of prescribed drugs; 6) it has additional synopsis and thesis friendly course work leading to comprehensive examinations; 7) the year two deals with research work of 6 credit hours leading to defense of thesis; 8) The MPhil in Physiological Sciences is fundamentally different from what is being offered elsewhere. It prepares and offers a good spring board to dovetail PhD studies as well as faculty and institutional development.

This is the first study that deals with innovative programmes in research, learning and education in the field of physiological sciences. This broad-based MPhil would make its recipients competent, critical, confident and productive learner. This is a completely unique design of a curriculum that has no comparable examples elsewhere. Our mission is to educate graduate students in the field of Physiological Sciences such that they have a complete grasp over the broad-based integrated concepts of basic health sciences. Upon completion of their education, the students will be able to use the duality of imagination and skepticism. Hence, the students will contribute to their fields by unfolding their creative energy.

Improving management of type 2 diabetes in South Asian patients: a systematic review of intervention studies

OBJECTIVES

Optimal control of type 2 diabetes is challenging in many patient populations including in South Asian patients. We systematically reviewed studies on the effect of diabetes management interventions targeted at South Asian patients with type 2 diabetes on glycaemic control.

DESIGN

Systematic review of MEDLINE, EMBASE and CINAHL databases for randomised controlled trials (RCTs) and pre-post-test studies (January 1990 to February 2014). Studies were stratified by where interventions were conducted (South Asia vs Western countries).

PARTICIPANTS

Patients originating from Pakistan, Bangladesh or India with type 2 diabetes.

PRIMARY OUTCOME

Change in glycated haemoglobin (HbA1c). Secondary end points included change in blood pressure, lipid levels, anthropomorphics and knowledge.

RESULTS

23 studies (15 RCTs) met criteria for analysis with 7 from Western countries (n=2532) and 16 from South Asia (n=1081). Interventions in Western countries included translated diabetes education, additional clinical care, written materials, visual aids, and bilingual community-based peers and/or health professionals. Interventions conducted in South Asia included yoga, meditation or exercise, community-based peers, health professionals and dietary education (cooking exercises). Among RCTs in India (5 trials; n=390), 4 demonstrated significant reductions in HbA1c in the intervention group compared with usual care (yoga and exercise interventions). Among the 4 RCTs conducted in Europe (n=2161), only 1 study, an education intervention of 113 patients, reported a significant reduction in HbA1c with the intervention. Lipids, blood pressure and knowledge improved in both groups with studies from India more often reporting reductions in body mass index and waist circumference.

CONCLUSIONS

Overall, there was little improvement in HbA1c level in diabetes management interventions targeted at South Asians living in Europe compared with usual care, although other outcomes did improve. The smaller studies in India demonstrated significant improvements in glycaemic and other end points. Novel strategies are needed to improve glycaemic control in South Asians living outside of India.

A Comprehensive Study on Mo/CdTe Metal-Semiconductor Interface Deposited by Radio Frequency Magnetron Sputtering

Metal-semiconductor (MS) junction between Mo and CdTe, which is one of the fundamental issues for CdTe based solar cell, has been investigated for films deposited on different substrates. XRD pattern of Mo/CdTe films on the polyimide (PI) substrate shows a strong preferential orientation of MoTe2 in (100) at 2θ = 29.44 degrees, which becomes less apparent as deposition time of CdTe increases. However, on soda lime glass (SLG) no such XRD reflection pattern is observed. Moreover, from EDX measurement, Mo-Te compound also identifies MoTe2 at Mo/CdTe interface on PI substrate, which is not present on SLG. Bulk carrier concentration of Mo/CdTe films on PI substrate for lower deposition time of CdTe is found 1.42 x 10(18) cm(-3), which is almost equal to MoTe2. Thereafter, it decreases as CdTe growth time increases. The type of unintentionally formed MoTe2 on PI substrate is found to be n-type in nature. Lattice constants of a = 6.5 Å for CdTe and a = 3.52 Å for MoTe2 are found from nanostructure study by TEM.

Effect of Sn Doping on the Properties of Nano-Structured ZnO Thin Films Deposited by Co-Sputtering Technique

In this study, tin doped zinc oxide (ZnO:Sn) nano-structured thin films were successfully deposited by co-sputtering of ZnO and Sn on top of glass substrate. The effect of Sn doping on the microstructure, phase, morphology, optical and electrical properties of the films were extensively investigated by means of XRD, EDX, SEM, AFM, Hall Effect measurement, and UV-Vis spectrometry. The results showed that the undoped ZnO film exhibited preferred orientation along the c-axis of the hexagonal wurtzite structure. With increase of Sn doping, the peak position of the (002) plane was shifted to the higher 20 values, and ultimately changed to amorphous structure. The absorption edge was shifted to blue region which confirmed the excitonic quantum confinement effect in the films. Consequently, improved surface morphology with optical bandgap, reduced average particle size, reduced resistivity, enhanced Hall mobility and carrier concentration were observed in the doped films after vacuum annealing. Among all of the as-deposited and annealed ZnO:Sn films investigated in this study, annealed film doped with 8 at.% of Sn concentration exhibited the best properties with a bandgap of 3.84 eV, RMS roughness of 2.51 nm, resistivity of 2.36 ohm-cm, and Hall mobility of 83 cm2 V(-1) s(-1).

The Relationship between Total Water Intake and Cognitive Control among Prepubertal Children

BACKGROUND

Cognitive control (also known as executive function) encompasses mental processes that underlie goal-directed behavior, and it enables us to adjust our behavior according to changing environmental demands. Previous research among children has demonstrated that aerobic fitness and obesity have contrasting and selective effects on cognitive control. However, the relationship between water intake and childhood cognitive control remains inadequately studied. This study investigated the relationship between total water intake and cognitive control among prepubertal children (8-9-year olds).

METHODS

Children between 8 and 9 years of age (n = 63) performed a modified flanker task to assess cognitive control related to inhibition (ability to resist distractions and maintain focus). Diet was measured using 3-day food records. Total water was defined as water consumed from drinking water, beverages, and food.

RESULTS

A comparison of task performance across the median intake of total water revealed that children above the median exhibited shorter reaction times across multiple conditions of the flanker task, requiring variable amounts of cognitive control. Further, after adjustment of age, IQ, socioeconomic status, weight status, and aerobic fitness level, the proportion of intake comprised of water (%TW) was negatively correlated with reaction time interference, that is, the ability to maintain task performance when task conditions demanded greater inhibition.

CONCLUSIONS

These results indicate an association between water intake and cognitive control using a task that modulates inhibition. Specifically, higher water intake correlated with greater ability to maintain task performance when inhibitory demands are increased. Future work is needed to determine the mechanism by which water influences cognitive control among children.

Diabetes in the young: a population-based study of South Asian, Chinese and White people

AIMS

Rates of diabetes mellitus in the young have not been quantified on a population level, particularly in South Asian and Chinese populations, which bear high rates of diabetes. We determined the incidence of diabetes (Type 2 diabetes and diabetes using insulin only) and rates of hospitalizations among South Asian, Chinese and White people aged 5-29 years with newly diagnosed diabetes.

METHODS

People with newly diagnosed diabetes (1997-2006) in British Columbia, Canada were identified using population-based administrative data and pharmacy databases. Age-standardized incidence rates were calculated for people with diabetes prescribed insulin only and those with Type 2 diabetes. They were followed for up to 8 years for all hospitalizations and diabetes-related complications.

RESULTS

There were 712 South Asians, 498 Chinese and 6176 White people aged 5-29 years with diabetes. Most youth with diabetes had Type 2 diabetes (South Asian 86.4%; Chinese 87.1% and White 61.8%). The incidence of diabetes on insulin only was highest in White people compared with the other groups. The incidence of Type 2 diabetes was highest in South Asians, particularly in 20-29-year-olds, with rates 2.2 times that of White people and 3.1 times that of Chinese people. Hospitalization and diabetes-related complications were uncommon in all groups.

CONCLUSION

The incidence of Type 2 diabetes is higher than previously estimated among youth and is now surpassing diabetes on insulin only. Significant reductions in Type 2 diabetes screening ages in South Asians need to be considered and prevention efforts are urgently required in childhood and adolescence. Global estimates need to consider the epidemic of Type 2 diabetes in the young.

Application of SCAR markers linked with mungbean yellow mosaic virus disease-resistance gene in Pakistan mungbean germplasm

Mungbean yellow mosaic virus disease (MYMVD) caused by single-stranded DNA begomovirus is the most prominent threat to the mungbean crop in Pakistan. Mungbean genotypes consisting of 127 varieties/lines were screened for MYMVD under natural field conditions. No genotypes were found to be immune or highly resistant against MYMVD. Genotypes showing resistant and tolerant responses in field screening trials were screened using sequence characterized amplified region (SCAR) markers linked with the MYMVD-resistance gene. SCAR markers amplified the desired band only in the resistant and tolerant genotypes, while no amplification was observed in susceptible genotypes. SCAR markers will be useful for future breeding and varietal developmental programs and mungbean genotypes can be screened on the molecular level.

Is there evidence of sexual reproduction (meiosis) in Acanthamoeba?

Evolution of independently breeding species into males and females (gametes) has remained a puzzle. Given the significant advantages of sexual reproduction over asexual reproduction as a long-term species survival strategy; here, we pose the question whether there is some form of meiosis in Acanthamoeba species, which represents our ancient lineage. The recently available Acanthamoeba genome revealed several genes implicated in meiosis in sexual eukaryotes such as Spo11, Mre11, Rad50, Rad51, Rad52, Mnd1, Dmc1, Msh, and Mlh, suggesting that Acanthamoeba is capable of some form of meiosis, inferring the presence of sexual reproduction in Acanthamoeba, and that meiosis evolved early in eukaryotic evolution.

An update on Acanthamoeba keratitis: diagnosis, pathogenesis and treatment

Free-living amoebae of the genus Acanthamoeba are causal agents of a severe sight-threatening infection of the cornea known as Acanthamoeba keratitis. Moreover, the number of reported cases worldwide is increasing year after year, mostly in contact lens wearers, although cases have also been reported in non-contact lens wearers. Interestingly, Acanthamoeba keratitis has remained significant, despite our advances in antimicrobial chemotherapy and supportive care. In part, this is due to an incomplete understanding of the pathogenesis and pathophysiology of the disease, diagnostic delays and problems associated with chemotherapeutic interventions. In view of the devastating nature of this disease, here we present our current understanding of Acanthamoeba keratitis and molecular mechanisms associated with the disease, as well as virulence traits of Acanthamoeba that may be potential targets for improved diagnosis, therapeutic interventions and/or for the development of preventative measures. Novel molecular approaches such as proteomics, RNAi and a consensus in the diagnostic approaches for a suspected case of Acanthamoeba keratitis are proposed and reviewed based on data which have been compiled after years of working on this amoebic organism using many different techniques and listening to many experts in this field at conferences, workshops and international meetings. Altogether, this review may serve as the milestone for developing an effective solution for the prevention, control and treatment of Acanthamoeba infections.

CD36 AA genotype is associated with decreased lipid taste perception in young obese, but not lean, children

BACKGROUND/OBJECTIVE

Obesity is an alarming threat for all age groups, including children. Fat overconsumption is one of the factors that directly influences this pathology. Recent studies have suggested that a common variant in the CD36 gene, that is, single-nucleotide polymorphism (SNP) rs1761667-A allele, that reduces CD36 expression, associates with high oral fat detection thresholds in some obese subjects. The objective was to assess fatty acid sensitivity in relation to CD36 SNP in young lean and obese children.

SUBJECTS/METHODS

We studied lingual detection thresholds for emulsions, containing oleic acid, in Algerian children (n=116, age=8±0.5 years) who were divided into two groups: obese (n=57; body mass index (BMI) z-score=2.513±0.490) and lean children (n=59; BMI z-score=-0.138±0.601) by alternative-forced choice method. To correlate the lipid taste perception thresholds with CD36 SNP, the children were genotyped for A/G SNP rs1761667 in 5'UTR region of CD36 by using PCR and restriction fragment length polymorphism.

RESULTS

We noticed significantly higher CD36 A-allele frequency (P=0.036) in young obese children compared with leans. CD36 A-allele was associated with higher lipid taste perception thresholds than G-allele in obese children, but not in lean controls. Moreover, waist circumference was positively correlated with reduced fat taste sensitivity in these children.

CONCLUSIONS

CD36 SNP A-allele, being present both in young lean and in obese children, is associated with high threshold for fatty acid taste sensitivity only in obese children.

Prescribing patterns and adherence to medication among South-Asian, Chinese and white people with type 2 diabetes mellitus: a population-based cohort study

AIM

To determine the prescribing of and adherence to oral hypoglycaemic agents, insulin, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and statin therapy among South-Asian, Chinese and white people with newly diagnosed diabetes.

METHODS

The present study was a population-based cohort study using administrative and pharmacy databases to include all South-Asian, Chinese and white people aged ≥ 35 years with diabetes living in British Columbia, Canada (1997-2006). Adherence to each class of medication was measured using proportion of days covered over 1 year with optimum adherence defined as ≥ 80%.

RESULTS

The study population included 9529 South-Asian, 14 084 Chinese and 143 630 white people with diabetes. The proportion of people who were prescribed angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statin or oral hypoglycaemic agents was ≤ 50% for all groups. South-Asian and Chinese people had significantly lower adherence for all medications than white people, with the lowest adherence to angiotensin-converting enzyme inhibitor treatment (South-Asian people: adjusted odds ratio 0.37, 95% CI 0.34-0.39; P<0.0001; Chinese people: adjusted odds ratio 0.50, 95% CI 0.47-0.54; P<0.0001) and statin therapy (South-Asian people: adjusted odds ratio 0.47, 95% CI 0.41 - 0.53, P < 0.0001; Chinese people: adjusted odds ratio 0.72, 95% CI 0.67 - 0.77; P<0.0001) compared with white people.

CONCLUSION

Adherence to evidence-based pharmacotherapy was substantially worse among the South-Asian and Chinese populations. Care providers need to be alerted to the high levels of non-adherence in these groups and the underlying causes need to be investigated.

Miliary nodules in a patient of allergic bronchopulmonary aspergilosis

Allergic bronchopulmonary aspergilosis (ABPA) is immunological pulmonary disease caused by hypersensitivity of aspergillus fumigatus usually occurs in patients with chronic asthma, cystic fibrosis and bronchiactasis. This disease may present with divers radiological presentation like; fleeting pulmonary opacities, bronchiactasis, mucoid impaction, perihilar opacity (hailer lymphadenopathy), and lung mass or pleural effusion. We describe the case of a 30 year old housewife who presented with progressive dysponea, low grade fever, dry cough, weight loss and miliary nodule in chest radiograph and high-resolution CT (HRCT) in a tertiary level hospital of Bangladesh. A diagnosis of ABPA was established on the basis of sputum routine microscopy and culture examination for fungus (Aspergillus).

Comparison of creatinine clearance estimates with routine measured creatinine clearance in hospitalized chronic kidney disease patients

The aim of this study was to determine the correlation between endogenous creatinine clearance (BSA adjusted), the Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault (BSA adjusted) equations in a Bangladeshi population with chronic kidney disease. It was an observational study conducted from July 2011 to January 2012 in the department of Medicine of Mymensingh Medical College Hospital, Mymensingh, Bangladesh. A total of 50 cases with diagnosed Chronic kidney disease (CKD) patients participated in this study. Results are expressed as mean and standard deviation (SD). Pearson correlation coefficient (r) was used to compare the results of conventional creatinine clearance on 24 hour urine collection (BSA adjusted) and creatinine clearance calculated by Cockcroft-Gault creatinine clearance (BSA adjusted) and MDRD creatinine clearance (ml/min/1.73m²) equation. Among 50 patients 30(60%) were male and 20(40%) were female. Mean age of the cases was 43±12.96 years with age range from 18 to 65 years. Mean creatinine clearance measured on 24 hours urine collection (BSA adjusted) was 13.86±8.72ml/min per 1.73m². Mean BSA adjusted Cockcroft-Gault creatinine clearance and MDRD creatinine clearance were 27.68±11.26 and 24.46±11.05ml/min per 1.73m² respectively. There was a positive correlation between both the Modification of Diet in Renal Disease (r=0.951, p<0.05) equation and the Cockcroft-Gault (r=0.948, p<0.05) equation with measured creatinine clearance; the former being statistically superior comparing the correlation coefficients. The creatinine based formulas with their inherent property of convenience and cost effectiveness can be a useful tool for monitoring the progression of disease.

Bilateral hypertrophic olivary nucleus degeneration on magnetic resonance imaging in children with Leigh and Leigh-like syndrome

OBJECTIVE

Bilateral hypertrophic olivary degeneration on brain MRI has been reported in a few metabolic, genetic and neurodegenerative disorders, including mitochondrial disorders. In this report, we sought to analyse whether bilateral symmetrical inferior olivary nucleus hypertrophy is specifically associated with mitochondrial disorders in children.

METHODS

This retrospective study included 125 children (mean age, 7.6 ± 5 years; male:female, 2.6:1) diagnosed with various metabolic and genetic disorders during 2005-2012. The routine MRI sequences (T1 weighted, T2 weighted and fluid-attenuated inversion-recovery sequences) were analysed for the presence of bilateral symmetrical olivary hypertrophy and central tegmental tract or dentate nuclei signal changes. The other imaging findings and the final diagnoses were noted.

RESULTS

The cohort included patients with Leigh and Leigh-like syndrome (n = 25), other mitochondrial diseases (n = 25), Wilson disease (n = 40), Type 1 glutaric aciduria (n = 14), maple syrup urine disease (n = 13), giant axonal neuropathy (n = 5) and L-2 hydroxy glutaric aciduria (n = 3). Bilateral inferior olivary nucleus hypertrophy was noted in 10 patients, all of whom belonged to the Leigh and Leigh-like syndrome group.

CONCLUSION

Bilateral hypertrophic olivary degeneration on MRI is relatively often, but not routinely, seen in children with Leigh and Leigh-like syndrome. Early detection of this finding by radiologists and physicians may facilitate targeted metabolic testing in these children.

ADVANCES IN KNOWLEDGE

This article highlights the occurrence of bilateral hypertrophic olivary nucleus degeneration on MRI in children with Leigh and Leigh-like syndrome, compared with other metabolic disorders.