A short-oligonucleotide microarray that allows improved detection of gastrointestinal tract microbial communities

Background  

The human gastrointestinal (GI) tract contains a diverse collection of bacteria, most of which are unculturable by conventional microbiological methods. Increasingly molecular profiling techniques are being employed to examine this complex microbial community. The purpose of this study was to develop a microarray technique based on 16S ribosomal gene sequences for rapidly monitoring the microbial population of the GI tract.     

Proteomic analysis of circulating human monocytes in coronary artery disease

Monocytes play an important role in inflammation and atherosclerosis; however, the molecular details underlying these diverse functions are not completely understood. Proteomic analysis of monocytes can provide new insights into their biological role in coronary artery disease (CAD). Twenty angiographically confirmed male, CAD patients (≥50% stenosis) attending cardiology clinic of Nehru Hospital, PGIMER, Chandigarh, and who were not receiving any lipid lowering therapy and 20 TMT negative subjects who served as controls were enrolled in the study. Circulating monocytes isolated from overnight fasting blood samples were analyzed by 2D gel electrophoresis (pH 4-7), and differentially expressed protein spots were subjected to mass spectrometry and identification of proteins. We observed 333 ± 40 protein spots in monocytes from patients and 312 ± 20 in controls; out of which 63 protein spots showed altered intensity in CAD patients. Thirteen spots showed fivefold increased and two protein spots showed fivefold decreased expression in CAD group as compared to control group, respectively. Two proteins showing decreased expression in monocytes from CAD patients were identified as: (i) glutathione transferase and (ii) heat shock protein 70 KDa. Proteins showing increased expression in CAD patients were identified as: (i) vimentin, (ii) mannose binding lectin receptor protein, and (iii) S100A8 calcium-binding protein. The results of our study offer identification of several proteins in monocytes which can provide new perspectives in role of monocytes in pathogenesis of atherosclerosis.     

Complex binding interactions between multicomponent mixtures and odorant receptors in the olfactory organ of the Caribbean spiny lobster Panulirus argus

Our study was designed to examine how components of complex mixtures caninhibit the binding of other components to receptor sites in the olfactorysystem of the spiny lobster Panulirus argus. Biochemical binding assayswere used to study how two- to six-component mixtures inhibit binding ofthe radiolabeled odorants taurine, L-glutamate andadenosine-5'-monophosphate to a tissue fraction rich in dendritic membraneof olfactory receptor neurons. Our results indicate that binding inhibitionby mixtures can be large and is dependent on the nature of the odorantligand and on the concentration and composition of the mixture. The bindinginhibition by mixtures of structurally related components was generallypredicted using a competitive binding model and binding inhibition data forthe individual components. This was not the case for binding inhibition bymost mixtures of structurally unrelated odorants. The binding inhibitionfor these mixtures was generally smaller than that for one or more of theircomponents, indicating that complex binding interactions between componentscan reduce their ability to inhibit binding. The magnitude of bindinginhibition was influenced more by the mixture's precise composition than bythe number of components in it, since mixtures with few components weresometimes more inhibitory than mixtures with more components. Thesefindings raise the possibility that complex binding interactions betweencomponents of a mixture and their receptors may shape the output ofolfactory receptor neurons to complex mixtures.     

Microarray Noninvasive Neuronal Seizure Recordings from Intact Larval Zebrafish

Zebrafish epilepsy models are emerging tools in experimental epilepsy. Zebrafish larvae, in particular, are advantageous because they can be easily genetically altered and used for developmental and drug studies since agents applied to the bath penetrate the organism easily. Methods for electrophysiological recordings in zebrafish are new and evolving. We present a novel multi-electrode array method to non-invasively record electrical activity from up to 61 locations of an intact larval zebrafish head. This method enables transcranial noninvasive recording of extracellular field potentials (which include multi-unit activity and EEG) to identify epileptic seizures. To record from the brains of zebrafish larvae, the dorsum of the head of an intact larva was secured onto a multi-electrode array. We recorded from individual electrodes for at least three hours and quantified neuronal firing frequency, spike patterns (continuous or bursting), and synchrony of neuronal firing. Following 15 mM potassium chloride- or pentylenetetrazole-infusion into the bath, spike and burst rate increased significantly. Additionally, synchrony of neuronal firing across channels, a hallmark of epileptic seizures, also increased. Notably, the fish survived the experiment. This non-invasive method complements present invasive zebrafish neurophysiological techniques: it affords the advantages of high spatial and temporal resolution, a capacity to measure multiregional activity and neuronal synchrony in seizures, and fish survival for future experiments, such as studies of epileptogenesis and development.     

Citrullus lanatus ‘sentinel’ (watermelon) extract reduces atherosclerosis in LDL receptor-deficient mice

Watermelon (Citrullus lanatus or C. lanatus) has many potentially bioactive compounds including citrulline, which may influence atherosclerosis. In this study, we determined the effects of C. lanatus, provided as an extract of the cultivar ‘sentinel,’ on hypercholesterolemia-induced atherosclerosis in mice. Male low-density lipoprotein receptor-deficient mice at 8 weeks old were given either C. lanatus ‘sentinel’ extract (2% vol/vol; n= 10) or a mixture of matching carbohydrates (2% vol/vol; n= 8) as the control in drinking water while being fed a saturated fat-enriched diet for 12 weeks ad libitum. Mice consuming C. lanatus ‘sentinel’ extract had significantly increased plasma citrulline concentrations. Systolic blood pressure was comparable between the two groups. Consumption of C. lanatus ‘sentinel’ extract led to lower body weight and fat mass without influencing lean mass. There were no differences in food and water intake and in urine output between the two groups. C. lanatus ‘sentinel’ extract administration decreased plasma cholesterol concentrations that were attributed to reductions of intermediate-/low-density lipoprotein cholesterol. Plasma concentrations of monocyte chemoattractant protein-1 and interferon-gamma were decreased and those of interleukin-10 were increased in mice consuming C. lanatus ‘sentinel’ extract. Intake of C. lanatus ‘sentinel’ extract resulted in reductions of atherosclerosis in both aortic arch and thoracic regions. In conclusion, consumption of C. lanatus ‘sentinel’ extract led to reduced body weight gain, decreased plasma cholesterol concentrations, improved homeostasis of pro- and anti-inflammatory cytokines, and attenuated development of atherosclerosis without affecting systolic blood pressure in hypercholesterolemic mice.     

Trends in Resource Utilization by Children with Neurological Impairment in the United States Inpatient Health Care System: A Repeat Cross-Sectional Study

Background

Care advances in the United States (US) have led to improved survival of children with neurological impairment (NI). Children with NI may account for an increasing proportion of hospital resources. However, this assumption has not been tested at a national level.

Methods and Findings

We conducted a study of 25,747,016 US hospitalizations of children recorded in the Kids'' Inpatient Database (years 1997, 2000, 2003, and 2006). Children with NI were identified with International Classification of Diseases, 9th Revision, Clinical Modification diagnoses resulting in functional and/or intellectual impairment. We assessed trends in inpatient resource utilization for children with NI with a Mantel-Haenszel chi-square test using all 4 y of data combined. Across the 4 y combined, children with NI accounted for 5.2% (1,338,590) of all hospitalizations. Epilepsy (52.2% [n = 538,978]) and cerebral palsy (15.9% [n = 164,665]) were the most prevalent NI diagnoses. The proportion of hospitalizations attributable to children with NI did not change significantly (p = 0.32) over time. In 2006, children with NI accounted for 5.3% (n = 345,621) of all hospitalizations, 13.9% (n = 3.4 million) of bed days, and 21.6% (US$17.7 billion) of all hospital charges within all hospitals. Over time, the proportion of hospitalizations attributable to children with NI decreased within non-children''s hospitals (3.0% [n = 146,324] in 1997 to 2.5% [n = 113,097] in 2006, p<.001) and increased within children''s hospitals (11.7% [n = 179,324] in 1997 to 13.5% [n = 209,708] in 2006, p<0.001). In 2006, children with NI accounted for 24.7% (2.1 million) of bed days and 29.0% (US$12.0 billion) of hospital charges within children''s hospitals.

Conclusions

Children with NI account for a substantial proportion of inpatient resources utilized in the US. Their impact is growing within children''s hospitals. We must ensure that the current health care system is staffed, educated, and equipped to serve this growing segment of vulnerable children. Please see later in the article for the Editors'' Summary     

The cover of living and dead corals from airborne remote sensing

Trends in coral cover are widely used to indicate the health of coral reefs but are costly to obtain from field survey over large areas. In situ studies of reflected spectra at the coral surface show that living and recently dead colonies can be distinguished. Here, we investigate whether such spectral differences can be detected using an airborne remote sensing instrument. The Compact Airborne Spectrographic Imager (Itres Research Ltd, Canada) was flown in two configurations: 10 spectral bands with 1-m² pixels and 6 spectral bands with 0.25-m² pixels. First, we show that an instrument with 10 spectral bands possesses adequate spectral resolution to distinguish living Porites, living Pocillopora spp., partially dead Porites, recently dead Porites (total colony mortality within 6 months), old dead (>6 months) Porites, Halimeda spp., and coralline red algae when there is no water column to confuse spectra. All substrata were distinguished using fourth-order spectral derivatives around 538 nm and 562 nm. Then, at a shallow site (Tivaru) at Rangiroa Atoll, Tuamotu Archipelago (French Polynesia), we show that live and dead coral can be distinguished from the air to a depth of at least 4 m using first- and fourth-order spectral derivatives between 562–580 nm. However, partially dead and recently dead Porites colonies could not be distinguished from an airborne platform. Spectral differences among substrata are then exploited to predict the cover of reef substrata in ten 25-m² plots at nearby Motu Nuhi (max depth 8 m). The actual cover in these plots was determined in situ using quadrats with a 0.01-m² grid. Considerable disparity occurred between field and image-based measures of substrate cover within individual 25-m² quadrats. At this small scale, disparity, measured as the absolute difference in cover between field and remote-sensing methods, reached 25% in some substrata but was always less than 10% for living coral (99% of which consisted of Porites spp.). At the scale of the reef (all ten 25-m² quadrats), however, disparities in percent cover between imagery and field data were less than 10% for all substrata and extremely low for some classes (e.g. <3% for living Porites, recently dead Porites and Halimeda). The least accurately estimated substrata were sand and coralline red algae, which were overestimated by absolute values 7.9% and 6.6%, respectively. The precision of sampling was similar for field and remote-sensing methods: field methods required 19 plots to detect a 10% difference in coral cover among three reefs with a statistical power of 95%. Remote-sensing methods required 21 plots. However, it took 1 h to acquire imagery over 92,500 m² of reef, which represents 3,700 plots of 25 m² each, compared with 3 days to survey 10 such plots underwater. There were no significant differences in accuracy between 1-m² and 0.25-m² image resolutions, suggesting that the advantage of using smaller pixels is offset by reduced spectral information and an increase in noise (noise was observed to be 1.6–1.8 times greater in 0.25-m² pixels). We show that airborne remote sensing can be used to monitor coral and algal cover over large areas, providing that water is shallow and clear, and that brown fleshy macroalgae are scarce, that depth is known independently (e.g. from sonar survey).