177 research outputs found
A Prospective Study of Doppler Velocimetry in Pregnancy-induced Hypertension in a Rural Population of a Developing Country
Background: Pregnancy-induced hypertension (PIH) remains a great challenge to obstetricians. Doppler velocimetry can detect fetal compromise much before other antepartum tests.Aim: The aim of this study is to detect the changes of uterine artery, umbilical artery and middle cerebral artery in PIH by Doppler velocimetry.Subjects and Methods: This prospective study was conducted on hundred subjects with PIH. Doppler studies were carried, and parameters recorded in uterine, umbilical and middle cerebral artery (MCA) were Systolic/Diastolic ratio, Resistance Index, Cerebro Placental Index (CPI). Fetal outcomes were monitored. Statistical analysis was performed using Epi InfoTM software (Version 3.5.1, CDC, Atlanta). Test for significance was done with student’s t-test and Chi-square where applicable. A P- value of<0.05 was considered as significant.Results: Among the 100 subjects, 76 (76%) of fetuses had abnormal and 24% normal umbilical artery Doppler velocimetry; 62% had abnormal and 38% normal MCA Doppler velocimetry; 64% fetuses had abnormal and 36% normal CPI. In 95% of subjects having abnormal umbilical Doppler studies, caesarean section had to be done for acute fetal distress. Incidence of caesarean section was 61% in abnormal MCA group and 63% in abnormal CPI group. Among 14 patients who had abnormal uterine artery Doppler, four developed pre-eclampsia, 2 IUGR. In patients with notches in uterine artery Doppler, 38% developed pre-eclampsia, 38% had IUGR, 13% babies were still born and 25% of newborns required NICU admission. In umbilical artery Doppler, when S/D ratio was abnormal, 60% developed pre-eclampsia, 40% had IUGR and 40% of newborns had to be admitted in NICU.Conclusion: Doppler study for fetal surveillance in pregnancy-induced hypertension is a very useful device and abnormal umbilical artery and uterine artery velocimetry seems to have worse pregnancy outcomes in the present study. Notch as a single parameter is the best indicator with highest sensitivity and positive predicative values. However, combination of parameters is the best indicator. Keywords: Doppler study, fetomaternal outcome, pregnancy-induced hypertensio
Mapping coherence in measurement via full quantum tomography of a hybrid optical detector
Quantum states and measurements exhibit wave-like --- continuous, or
particle-like --- discrete, character. Hybrid discrete-continuous photonic
systems are key to investigating fundamental quantum phenomena, generating
superpositions of macroscopic states, and form essential resources for
quantum-enhanced applications, e.g. entanglement distillation and quantum
computation, as well as highly efficient optical telecommunications. Realizing
the full potential of these hybrid systems requires quantum-optical
measurements sensitive to complementary observables such as field quadrature
amplitude and photon number. However, a thorough understanding of the practical
performance of an optical detector interpolating between these two regions is
absent. Here, we report the implementation of full quantum detector tomography,
enabling the characterization of the simultaneous wave and photon-number
sensitivities of quantum-optical detectors. This yields the largest
parametrization to-date in quantum tomography experiments, requiring the
development of novel theoretical tools. Our results reveal the role of
coherence in quantum measurements and demonstrate the tunability of hybrid
quantum-optical detectors.Comment: 7 pages, 3 figure
Atomic scale investigation of silicon nanowires and nanoclusters
In this study, we have performed nanoscale characterization of Si-clusters and Si-nanowires with a laser-assisted tomographic atom probe. Intrinsic and p-type silicon nanowires (SiNWs) are elaborated by chemical vapor deposition method using gold as catalyst, silane as silicon precursor, and diborane as dopant reactant. The concentration and distribution of impurity (gold) and dopant (boron) in SiNW are investigated and discussed. Silicon nanoclusters are produced by thermal annealing of silicon-rich silicon oxide and silica multilayers. In this process, atom probe tomography (APT) provides accurate information on the silicon nanoparticles and the chemistry of the nanolayers
Association between variations in the TLR4 gene and incident type 2 diabetes is modified by the ratio of total cholesterol to HDL-cholesterol
<p>Abstract</p> <p>Background</p> <p>Toll-like receptor 4 (TLR4), the signaling receptor for lipopolysaccharides, is an important member of the innate immunity system. Since several studies have suggested that type 2 diabetes might be associated with changes in the innate immune response, we sought to investigate the association between genetic variants in the <it>TLR4 </it>gene and incident type 2 diabetes.</p> <p>Methods</p> <p>A case-cohort study was conducted in initially healthy, middle-aged subjects from the MONICA/KORA Augsburg studies including 498 individuals with incident type 2 diabetes and 1,569 non-cases. Seven SNPs were systematically selected in the <it>TLR4 </it>gene and haplotypes were reconstructed.</p> <p>Results</p> <p>The effect of <it>TLR4 </it>SNPs on incident type 2 diabetes was modified by the ratio of total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C). In men, four out of seven <it>TLR4 </it>variants showed significant interaction with TC/HDL-C after correction for multiple testing (p < 0.01). The influence of the minor alleles of those variants on the incidence of type 2 diabetes was observed particularly for male patients with high values of TC/HDL-C. Consistent with these findings, haplotype-based analyses also revealed that the effect of two haplotypes on incident type 2 diabetes was modified by TC/HDL-C in men (p < 10<sup>-3</sup>). However, none of the investigated variants or haplotypes was associated with type 2 diabetes in main effect models without assessment of effect modifications.</p> <p>Conclusion</p> <p>We conclude that minor alleles of several <it>TLR4 </it>variants, although not directly associated with type 2 diabetes might increase the risk for type 2 diabetes in subjects with high TC/HDL-C. Additionally, our results confirm previous studies reporting sex-related dissimilarities in the development of type 2 diabetes.</p
Inhibition of HCV 3a genotype entry through Host CD81 and HCV E2 antibodies
<p>Abstract</p> <p>Background</p> <p>HCV causes acute and chronic hepatitis which can eventually lead to permanent liver damage hepatocellular carcinoma and death. HCV glycoproteins play an important role in HCV entry by binding with CD81 receptors. Hence inhibition of virus at entry step is an important target to identify antiviral drugs against HCV.</p> <p>Methods and result</p> <p>The present study elaborated the role of CD81 and HCV glycoprotein E2 in HCV entry using retroviral pseudo-particles of 3a local genotype. Our results demonstrated that HCV specific antibody E2 and host antibody CD81 showed dose- dependent inhibition of HCV entry. HCV E2 antibody showed 50% reduction at a concentration of 1.5 ± 1 μg while CD81 exhibited 50% reduction at a concentration of 0.8 ± 1 μg. In addition, data obtained with HCVpp were also confirmed with the infection of whole virus of HCV genotype 3a in liver cells.</p> <p>Conclusion</p> <p>Our data suggest that HCV specific E2 and host CD81 antibodies reduce HCVpp entry and full length viral particle and combination of host and HCV specific antibodies showed synergistic effect in reducing the viral titer.</p
Beta catenin and cytokine pathway dysregulation in patients with manifestations of the "PTEN hamartoma tumor syndrome"
Background.
The "PTEN hamartoma tumor syndrome" (PHTS) includes a group of syndromes caused by germline mutations within the tumor suppressor gene "phosphatase and tensin homolog deleted on chromosome ten" (PTEN), characterized by multiple polyps in the gastrointestinal tract and by a highly increased risk of developing malignant tumours in many tissues.
The current work clarifies the molecular basis of PHTS in three unrelated Italian patients, and sheds light on molecular pathway disregulation constitutively associated to PTEN alteration.
Methods.
We performed a combination of RT-PCR, PCR, sequencing of the amplified fragments, Real Time PCR and western blot techniques.
Results.
Our data provide the first evidence of β-catenin accumulation in blood cells of patients with hereditary cancer syndrome caused by germ-line PTEN alteration. In addition, for the first time we show, in all PHTS patients analysed, alterations in the expression of TNFα, its receptors and IL-10. Importantly, the isoform of TNFRI that lacks the DEATH domain (TNFRSF1β) was found to be overexpressed.
Conclusion.
In light of our findings, we suggest that the PTEN pathway disregulation could determine, in non-neoplastic cells of PHTS patients, cell survival and pro-inflammatory stimulation, mediated by the expression of molecules such as β-catenin, TNFα and TNFα receptors, which could predispose these patients to the development of multiple cancers
Diphenyl Difluoroketone: A Potent Chemotherapy Candidate for Human Hepatocellular Carcinoma
Diphenyl difluoroketone (EF24), a molecule having structural similarity to curcumin, was recently reported to inhibit proliferation of various cancer cells significantly. Here we try to determine the effect and mechanism of EF24 on hepatocellular carcinoma. 2 µM EF24 was found to inhibit the proliferation of PLC/PRF/5, Hep3B, HepG2, SK-HEP-1 and Huh 7 cell lines. However, even 8 µM EF24 treatment did not affect the proliferation of normal liver LO2 cells. Accordingly, 20 mg/kg/d EF24 inhibited the growth of the tumor xenografts conspicuously while causing no apparent change in liver, spleen or body weight. In addition, significant apoptosis and G2/M phase cell cycle arrest were found using flow cytometry. Besides, caspases and PARP activation and features typical of apoptosis including fragmented nuclei with condensed chromatin were also observed. Furthermore, the mechanism was targeted at the reduction of nuclear factor kappa b (NF-κB) pathway and the NF-κB–regulated gene products Bcl-2, COX-2, Cyclin B1. Our study has offered a strategy that EF24 being a therapeutic agent for hepatocellular carcinoma
Down-regulation of IRES containing 5'UTR of HCV genotype 3a using siRNAs
<p>Abstract</p> <p>Background</p> <p>Hepatitis C virus (HCV) is a major causative agent of liver associated diseases leading to the development of hepatocellular carcinoma (HCC) all over the world and genotype-3a responsible for most of the cases in Pakistan. Due to the limited efficiency of current chemotherapy of interferon-α (IFN-α) and ribavirin against HCV infection alternative options are desperately needed out of which the recently discovered RNAi represent a powerful silencing approach for molecular therapeutics through a sequence-specific RNA degradation process to silence virus infection or replication. HCV translation is mediated by a highly conserved internal ribosome entry site (IRES) within the 5'UTR region making it a relevant target for new drug development.</p> <p>Materials and methods</p> <p>The present study was proposed to assess and explore the possibility of HCV silencing using siRNA targeting 5'UTR. For this analysis full length HCV 5'UTR of HCV-3a (pCR3.1/5'UTR) was tagged with GFP protein for <it>in vitro </it>analysis in Huh-7 cells. siRNA targeting 5'UTR were designed, and tested against constructed vector in Huh-7 cell line both at RNA and Protein levels. Furthermore, the effect of these siRNAs was confirmed in HCV-3a serum infected Huh-7 cell line.</p> <p>Results</p> <p>The expression of 5'UTR-GFP was dramatically reduced both at mRNA and protein levels as compared with Mock transfected and control siRNAs treated cells using siRNAs against IRES of HCV-3a genotype. The potential of siRNAs specificity to inhibit HCV-3a replication in serum-infected Huh-7 cells was also investigated; upon treatment with siRNAs a significant decrease in HCV viral copy number and protein expression was observed.</p> <p>Conclusions</p> <p>Overall, the present work of siRNAs against HCV 5'UTR inhibits HCV-3a expression and represents effective future therapeutic opportunities against HCV-3a genotype.</p
Optimization of Time-Course Experiments for Kinetic Model Discrimination
Systems biology relies heavily on the construction of quantitative models of biochemical networks. These models must have predictive power to help unveiling the underlying molecular mechanisms of cellular physiology, but it is also paramount that they are consistent with the data resulting from key experiments. Often, it is possible to find several models that describe the data equally well, but provide significantly different quantitative predictions regarding particular variables of the network. In those cases, one is faced with a problem of model discrimination, the procedure of rejecting inappropriate models from a set of candidates in order to elect one as the best model to use for prediction
The Chemical Information Ontology: Provenance and Disambiguation for Chemical Data on the Biological Semantic Web
Cheminformatics is the application of informatics techniques to solve chemical problems in silico. There are many areas in biology where cheminformatics plays an important role in computational research, including metabolism, proteomics, and systems biology. One critical aspect in the application of cheminformatics in these fields is the accurate exchange of data, which is increasingly accomplished through the use of ontologies. Ontologies are formal representations of objects and their properties using a logic-based ontology language. Many such ontologies are currently being developed to represent objects across all the domains of science. Ontologies enable the definition, classification, and support for querying objects in a particular domain, enabling intelligent computer applications to be built which support the work of scientists both within the domain of interest and across interrelated neighbouring domains. Modern chemical research relies on computational techniques to filter and organise data to maximise research productivity. The objects which are manipulated in these algorithms and procedures, as well as the algorithms and procedures themselves, enjoy a kind of virtual life within computers. We will call these information entities. Here, we describe our work in developing an ontology of chemical information entities, with a primary focus on data-driven research and the integration of calculated properties (descriptors) of chemical entities within a semantic web context. Our ontology distinguishes algorithmic, or procedural information from declarative, or factual information, and renders of particular importance the annotation of provenance to calculated data. The Chemical Information Ontology is being developed as an open collaborative project. More details, together with a downloadable OWL file, are available at http://code.google.com/p/semanticchemistry/ (license: CC-BY-SA)
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