Landscape structure influences natural pest suppression in a rice agroecosystem.

Agricultural landscapes are constantly changing as farmers adopt new production practices and respond to changing environmental conditions. Some of these changes alter landscape structure with impacts on natural pest control, pesticide use, and conservation of biodiversity. In rice agroecosystems the effect of landscape structure on natural enemies and pest suppression is often poorly understood. Here we investigate the effect of landscape composition and configuration on a key pest of rice, the brown planthopper (Nilaparvata lugens). Using N. lugens as sentinel prey coupled with predator exclusions, we investigated landscape effects on herbivore suppression and rice grain yield at multiple spatial scales in two regions of Bangladesh. Ladybird beetles and spiders were the most abundant natural enemies of N. lugens with landscape effects observed at all scales on ladybird beetles. Specifically, ladybird beetles were positively influenced by road edges, and fallow land, while spiders were strongly influenced only by rice phenology. Predator exclusion cages showed that N. lugens abundance significantly increased in caged plots, reducing rice gain yield. We also used an estimated biocontrol service index that showed a significant positive relationship with landscape diversity and a significant negative impact on pest density and yield loss. These results suggest that promoting fallow lands and fragmented patches between rice fields could lead to more sustainable insect pest management in rice agroecosystems, potentially reducing the practice of prophylactic insecticide use.

ADC Histogram Analysis of Pediatric Low-Grade Glioma Treated with Selumetinib: A Report from the Pediatric Brain Tumor Consortium.

BACKGROUND AND PURPOSE: Selumetinib is a promising MAP (mitogen-activated protein) kinase (MEK) 1/2 inhibitor treatment for pediatric low-grade gliomas. We hypothesized that MR imaging-derived ADC histogram metrics would be associated with survival and response to treatment with selumetinib. MATERIALS AND METHODS: Children with recurrent, refractory, or progressive pediatric low-grade gliomas who had World Health Organization grade I pilocytic astrocytoma with KIAA1549-BRAF fusion or the BRAF V600E mutation (stratum 1), neurofibromatosis type 1-associated pediatric low-grade gliomas (stratum 3), or sporadic non-neurofibromatosis type 1 optic pathway and hypothalamic glioma (OPHG) (stratum 4) were treated with selumetinib for up to 2 years. Quantitative ADC histogram metrics were analyzed for total and enhancing tumor volumes at baseline and during treatment. RESULTS: Each stratum comprised 25 patients. Stratum 1 responders showed lower values of SD of baseline ADC_total as well as a larger decrease with time on treatment in ADC_total mean, mode, and median compared with nonresponders. Stratum 3 responders showed a greater longitudinal decrease in ADC_total. In stratum 4, higher baseline ADC_total skewness and kurtosis were associated with shorter progression-free survival. When all 3 strata were combined, responders showed a greater decrease with time in ADC_total mode and median. Compared with sporadic OPHG, neurofibromatosis type 1-associated OPHG had lower values of ADC_total mean, mode, and median as well as ADC_enhancement mean and median and higher values of ADC_total skewness and kurtosis at baseline. The longitudinal decrease in ADC_total median during treatment was significantly greater in sporadic OPHG compared with neurofibromatosis type 1-associated OPHG. CONCLUSIONS: ADC histogram metrics are associated with progression-free survival and response to treatment with selumetinib in pediatric low-grade gliomas.

Salinity Influences Plant-Pest-Predator Tritrophic Interactions.

Climate change-induced salinity intrusion into agricultural soils is known to negatively impact crop production and food security. However, the effects of salinity increase on plant-herbivore-natural enemy systems and repercussions for pest suppression services are largely unknown. Here, we examine the effects of increased salinity on communities of rice (Oryza sativa), brown planthopper (BPH), Nilaparvata lugens, and green mirid bug (GMB), Cyrtorhinus lividipennis, under greenhouse conditions. We found that elevated salinity significantly suppressed the growth of two rice cultivars. Meanwhile, BPH population size also generally decreased due to poor host plant quality induced by elevated salinity. The highest BPH density occurred at 2.0 dS/m salinity and declined thereafter with increasing salinity, irrespective of rice cultivar. The highest population density of GMB also occurred under control conditions and decreased significantly with increasing salinity. Higher salinity directly affected the rice crop by reducing plant quality measured with reference to biomass production and plant height, whereas inducing population developmental asynchrony between BPH and GMB observed at 2 dS/m salinity and potentially uncoupling prey-predator dynamics. Our results suggest that increased salinity has harmful effects on plants, herbivores, natural enemies, as well as plant-pest-predator interactions. The effects measured here suggest that the bottom-up effects of predatory insects on rice pests will likely decline in rice produced in coastal areas where salinity intrusion is common. Our findings indicate that elevated salinity influences tritrophic interactions in rice production landscapes, and further research should address resilient rice insect pest management combining multipests and predators in a changing environment.

Hypertension in School Children of Dhaka City and Associated Risk Factors.

Hypertension has its origin in childhood but goes undetected unless specially looked for detection of hypertension in children will increase the awareness and lead to preventive strategies. The objective of the study was to determine the prevalence of hypertension in school children. This cross sectional study was conducted among children aged 10 to 17 years in three secondary level schools of Dhaka city, Bangladesh. This study included 1146 participants (both boys and girls) by systematic random sampling. Blood pressure was measured and plotted in Blood pressure (BP) chart to define hypertension and structured questionnaire were used to collect socio demographic information. The prevalence of hypertension in school children was 1.8% (male was 1.68% and female was 1.99%). It was noted that there was a strong correlation between body weight and BMI of the children with hypertension. A significant portion of the respondents had family history of hypertension, diabetes and obesity. There was also a positive relation between hypertension and food habit that include low vegetables and more fast food. It was concluded that hypertension exists among secondary level school children in Dhaka, Bangladesh and it is related with obesity, increased BMI, family history and dietary habit.

Establishing next-generation pest control services in rice fields: eco-agriculture.

Pesticides are commonly used in food crop production systems to control crop pests and diseases and ensure maximum yield with high market value. However, the accumulation of these chemical inputs in crop fields increases risks to biodiversity and human health. In addition, people are increasingly seeking foods in which pesticide residues are low or absent and that have been produced in a sustainable fashion. More than half of the world's human population is dependent on rice as a staple food and chemical pesticides to control pests is the dominant paradigm in rice production. In contrast, the use of natural enemies to suppress crop pests has the potential to reduce chemical pesticide inputs in rice production systems. Currently, predators and parasitoids often do not persist in rice production landscapes due to the absence of shelter or nutritional sources. In this study, we modified the existing rice landscape through an eco-engineering technique that aims to increase natural biocontrol agents for crop protection. In this system, planting nectar-rich flowering plants on rice bunds provides food and shelter to enhance biocontrol agent activity and reduce pest numbers, while maintaining grain yield. The abundance of predators and parasitoids and parasitism rates increased significantly in the eco-engineering plots compared to the insecticide-treated and control plots. Moreover, a significantly lower number of principal insect pests and damage symptoms were found in treatments where flowering plants were grown on bunds than in plots where such plants were not grown. This study indicates that manipulating habitat for natural enemies in rice landscapes enhances pest suppression and maintains equal yields while reducing the need for insecticide use in crop fields.

Coronary angiographic profile in bangladeshi patients with metabolic syndrome and ischemic heart disease.

The metabolic syndrome, which is characterized by a constellation of fasting hyperglycemia, hypertriglyceridemia, low HDL cholesterol, hypertension, and/or abdominal obesity, is a risk factor for the development of coronary artery disease (CAD) and cardiovascular events. We evaluated interrelationships between angiographic CAD and the metabolic syndrome, in 478 patients who were referred for coronary angiography to evaluate suspected myocardial ischemia in the department of cardiology of BSMMU between June 2007 and May 2008. We applied the criteria for the metabolic syndrome proposed by ATP III guideline. Study populations were divided into two groups on the basis of presence or absence of metabolic syndrome. Age was similar in both groups. Body mass index (BMI) was higher (26.22 ± 1.94 vs. 22.07 ± 1.55) in metabolic syndrome group (p ≤ 0.0001). All parameters, waist circumference (103.16 ± 10.21 vs. 91.45 ± 7.61) cm, blood pressure both systolic (141.34 ± 21.49 vs. 127.94 ± 13.01) and diastolic (86.8 5 ± 8.42 vs. 79.28 ± 7.77) mm of Hg, serum triglyceride (248.32 ± 77.88 vs. 128.35 ± 19.00)mg/dl, fasting blood glucose (125.40 ± 22.86 vs. 95.65 ± 10.63)mg/dl were significantly higher in metabolic syndrome group (p value=0.0001), whereas HDL (33.10 ± 6.55 vs. 39.30 ± 6.17)mg/dl was lower (p value = 0.0001). More subjects in metabolic syndrome were having type B (55.60% vs. 31.00%) and type C (9.50% vs. 2.70%) lesion as compared to non-metabolic syndrome group. Involvement of left main artery was more (4.80% vs. 0.90%) in metabolic syndrome group. Metabolic syndrome has primary predictive ability for CAD. A metabolic profile should form part of the risk assessment in all patients with coronary disease, not just those who are obese.

Impact of nitric oxide precursor L-arginine on oxidative stress against typhoid.

OBJECTIVES: Typhoid fever is a global health problem caused by Salmonella. Salmonellae are gram-negative, flagellate, nonsporulating, facultative anaerobic bacilli that ferment glucose, reduce nitrate to nitrite, and synthesize peritrichous flagella when motile. Nowadays, most of the drugs are resistant, the fact of which compels the search for formulated drugs. Nitric oxide (NO) and its congeners react with different compounds or radicals probably mediating the broad-spectrum antimicrobial activity of reactive nitrogen species (RNS) as well as reactive oxygen species (ROS) against diverse microorganisms. Exogenous administration of L-arginine results in increased NO production. The formulation of NO precursors, (i.e. of L -arginine and ciprofloxacin) is used against experimentally induced salmonellosis. Lipid hydroperoxide can be decomposed to produce alkoxy and peroxy radicals which eventually yield numerous carbonyl products such as malondialdehyde (MDA). MATERIAL AND METHODS: Estimation of lipid peroxidation (LPO) was done by modified method of Utley et al (1967). RESULTS AND DISCUSSION: Infection with S. typhimurium significantly induced lipid peroxidation on days 8 and 11 as indicated by enhancement of MDA levels compared to the control mice (20 % and 9.52 %) (Tab. 1, Fig. 2, Ref. 20).

Pattern of congenital heart diseases.

This prospective observational study was done to find out the frequency of various forms of congenital heart disease (CHD) diagnosed by echocardiography. During the study period (January 2002 to December 2005) 2050 patients were screened by echocardiography. All patients were evaluated by cardiologists and had chest radiograph, electrocardiogram and echocardiography. Total 2050 patients were studied and among them 1071 had congenital heart disease. Male was 561(52.38%) and female was 510(47.62%). Atrial septal defect (ASD) was 374(34.92%), ventricular septal defect (VSD) was 318(29.69%), patent ductus arteriosus (PDA) 83(7.75%), pulmonary stenosis (PS) 58(5.42%), tetralogy of Fallot 162(15.13%), transposition of great vessels (TGA) 16(1.49%), Ebstein anomaly 5(0.4%), coarctation of aorta 1(0.09%) and single ventricle 2(0.19%). This distribution is more or less similar to that reported in studies at home and abroad. In this study atrial septal defect (ASD) was the commonest in acyanotic CHD and tetralogy of Fallot was the commonest cyanotic CHD.

Trimetazidine in the prevention of contrast induced nephropathy after coronary angiogram.

This prospective randomized, controlled trial was done to evaluate the efficacy of trimetazidine in the prevention of contrast induced nephropathy in patients with raised serum creatinine levels undergoing coronary angiogram. This study was performed in the Department of Cardiology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from April 2009 to March 2010. Contrast-induced nephropathy (CIN) is a serious complication of coronary angiography that is associated with considerably increased mortality and morbidity, including the need for short-term haemodialysis, extended hospitalisation and permanent impairment of renal function. Trimetazidine (TMZ) has been described as a cellular anti-ischaemic agent. This study was trial with 400 patients. Among them 200 patients treated with trimetazidine plus hydration with normal saline and 200 patients (control) given hydration by normal saline only. It was found that the incidence of CIN was significantly (p<0.05) reduced by trimetazidine administration with saline in comparison with saline alone in patients undergoing coronary angiogram (4% vs. 14%).

Clinical and angiographic profile of congenital anomalous origin of coronary arteries.

Coronary artery anomalies were found in 24(0.6%) patients undergoing coronary arteriography at University Cardiac Center, Bangabandhu Sheikh Mujib Medical University, Dhaka from 2004 to 2007. Of the 24 patient, 21(87.5%) had anomalies of origin and distribution and 3(12.5%) had coronary artery fistulae. Most coronary anomalies did not result in signs, symptoms or complications and usually were discovered as an incidental finding at the time of catheterization. Most of them were benign anomalies: i) separate origin of left anterior descending and circumflex from sinus of valsalva; ii) ectopic origin of circumflex from right sinus of valsalva; iii) Anomalous origin of left main coronary artery from right coronary artery; iv) anomalous coronary origin from ascending aorta; v) absent left circumflex; vi) double right coronary artery; vii) small coronary artery fistula. These anomalies may be associated with potentially serious sequelae such as angina pectoris, myocardial infarction, syncope, cardiac arrhythmias, congestive heart failure, or sudden death. In this study large coronary artery fistula was found as potentially serious anomaly. So coronary artery anomalies require accurate recognition for the appropriate management of the patients.