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31.

Background

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a severely debilitating disease of unknown pathogenesis consisting of a variety of symptoms including severe fatigue. The objective of the study was to examine the efficacy and safety of a TLR-3 agonist, rintatolimod (Poly I: C12U), in patients with debilitating CFS/ME.

Methods and Findings

A Phase III prospective, double-blind, randomized, placebo-controlled trial comparing twice weekly IV rintatolimod versus placebo was conducted in 234 subjects with long-standing, debilitating CFS/ME at 12 sites. The primary endpoint was the intra-patient change from baseline at Week 40 in exercise tolerance (ET). Secondary endpoints included concomitant drug usage, the Karnofsky Performance Score (KPS), Activities of Daily Living (ADL), and Vitality Score (SF 36). Subjects receiving rintatolimod for 40 weeks improved intra-patient placebo-adjusted ET 21.3% (p = 0.047) from baseline in an intention-to-treat analysis. Correction for subjects with reduced dosing compliance increased placebo-adjusted ET improvement to 28% (p = 0.022). The improvement observed represents approximately twice the minimum considered medically significant by regulatory agencies. The rintatolimod cohort vs. placebo also reduced dependence on drugs commonly used by patients in an attempt to alleviate the symptoms of CFS/ME (p = 0.048). Placebo subjects crossed-over to receive rintatolimod demonstrated an intra-patient improvement in ET performance at 24 weeks of 39% (p = 0.04). Rintatolimod at 400 mg twice weekly was generally well-tolerated.

Conclusions/Significance

Rintatolimod produced objective improvement in ET and a reduction in CFS/ME related concomitant medication usage as well as other secondary outcomes.

Trial Registration

ClinicalTrials.gov NCT00215800  相似文献   
32.

Background

α-defensin-5 (HD5) is a key effector of the innate immune system with broad anti-bacterial and anti-viral activities. Specialized epithelial cells secrete HD5 in the genital and gastrointestinal mucosae, two anatomical sites that are critically involved in HIV-1 transmission and pathogenesis. We previously found that human neutrophil defensins (HNP)-1 and -2 inhibit HIV-1 entry by specific bilateral interaction both with the viral envelope and with its primary cellular receptor, CD4. Despite low amino acid identity, human defensin-5 (HD5) shares with HNPs a high degree of structural homology.

Methodology/Principal Findings

Here, we demonstrate that HD5 inhibits HIV-1 infection of primary CD4+ T lymphocytes at low micromolar concentration under serum-free and low-ionic-strength conditions similar to those occurring in mucosal fluids. Blockade of HIV-1 infection was observed with both primary and laboratory-adapted strains and was independent of the viral coreceptor-usage phenotype. Similar to HNPs, HD5 inhibits HIV-1 entry into the target cell by interfering with the reciprocal interaction between the external envelope glycoprotein, gp120, and CD4. At high concentrations, HD5 was also found to downmodulate expression of the CXCR4 coreceptor, but not of CCR5. Consistent with its broad spectrum of activity, antibody competition studies showed that HD5 binds to a region overlapping with the CD4- and coreceptor-binding sites of gp120, but not to the V3 loop region, which contains the major determinants of coreceptor-usage specificity.

Conclusion/Significance

These findings provide new insights into the first line of immune defense against HIV-1 at the mucosal level and open new perspectives for the development of preventive and therapeutic strategies.  相似文献   
33.
ABSTRACT: BACKGROUND: Medical records accumulate data concerning patient health and the natural history of disease progression. However, methods to mine information systematically in a form other than an electronic health record are not yet available. The purpose of this study was to develop an object modeling technique as a first step towards a formal database of medical records. METHOD: Live Sequence Charts (LSC) were used to formalize the narrative text obtained during a patient interview. LSCs utilize a visual scenario-based programming language to build object models. LSC extends the classical language of UML message sequence charts (MSC), predominantly through addition of modalities and providing executable semantics. Interobject scenarios were defined to specify natural history event interactions and different scenarios in the narrative text. Result A simulated medical record was specified into LSC formalism by translating the text into an object model that comprised a set of entities and events. The entities described the participating components (i.e., doctor, patient and record) and the events described the interactions between elements. A conceptual model is presented to illustrate the approach. An object model was generated from data extracted from an actual new patient interview, where the individual was eventually diagnosed as suffering from Chronic Fatigue Syndrome (CFS). This yielded a preliminary formal designated vocabulary for CFS development that provided a basis for future formalism of these records. CONCLUSIONS: Translation of medical records into object models created the basis for a formal database of the patient narrative that temporally depicts the events preceding disease, the diagnosis and treatment approach. The LSCs object model of the medical narrative provided an intuitive, visual representation of the natural history of the patient's disease.  相似文献   
34.
We have investigated the interrelationship between diet, gut microbial ecology, and energy balance using a mouse model of obesity produced by consumption of a prototypic Western diet. Diet-induced obesity (DIO) produced a bloom in a single uncultured clade within the Mollicutes class of the Firmicutes, which was diminished by subsequent dietary manipulations that limit weight gain. Microbiota transplantation from mice with DIO to lean germ-free recipients promoted greater fat deposition than transplants from lean donors. Metagenomic and biochemical analysis of the gut microbiome together with sequencing and metabolic reconstructions of a related human gut-associated Mollicute (Eubacterium dolichum) revealed features that may provide a competitive advantage to members of the bloom in the Western diet nutrient milieu, including import and processing of simple sugars. Our study illustrates how combining comparative metagenomics with gnotobiotic mouse models and specific dietary manipulations can disclose the niches of previously uncharacterized members of the gut microbiota.  相似文献   
35.
The high alcohol-preferring (HAP) and low alcohol-preferring (LAP) mice were selectively bred for differences in alcohol preference and consumption. Recently, a large-effect QTL was identified on chromosome 9. The peak for this QTL is near the Drd2 (dopamine receptor 2) locus. The present study examined Drd2 mRNA expression differences between the HAP1 and LAP1 mice in brain regions important in the dopaminergic-reward pathway, including the nucleus accumbens, hippocampus, amygdala, and septum. Results show that alcohol-naïve HAP1 mice exhibited lower levels of Drd2 mRNA expression in the nucleus accumbens and the hippocampus compared to LAP1 mice. No differences were found in the amygdala or septum. To determine if a sequence difference might underlie the expression difference, the Drd2 cDNA was sequenced in each line and one single nucleotide polymorphism (SNP) was identified in the 3′ UTR. Both HAP and LAP 3′ UTR were cloned in the luc-pGL3-promoter-luc vector. The polymorphism in the Drd2 3′ UTR was assessed to determine its functional significance in modulating expression. In vitro expression analysis using neuroblastoma SK-N-SH cells resulted in a significant decrease in expression of the HAP 3′ UTR luc construct compared with the LAP 3′ UTR construct. This decreased expression is consistent with lower levels of Drd2 expression in the nucleus accumbens and the hippocampus as evidenced by qRT-PCR. These results suggest that the SNP may play a role in the differential expression of Drd2 between the HAP and LAP mice and that the polymorphism in Drd2 may contribute to alcohol preference.  相似文献   
36.
37.
Acanthaceae (Asteridae; Lamiales) include ~4000 species and encompass a range of morphological diversity, habitats, and biogeographic patterns. Although they are important components of tropical and subtropical habitats worldwide, inadequate knowledge of the family's phylogenetic framework has impeded comparative research. In this study, we sampled all known lineages of Acanthaceae including Andrographideae. Also included were eight of 13 genera whose relationships remain enigmatic. We used sequence data from nrITS and four chloroplast noncoding regions, and parsimony and Bayesian methods of analysis. Results strongly support most aspects of relationships including inclusion of Avicennia in Acanthaceae. Excepting Neuracanthus, newly sampled taxa are placed with strong support; Kudoacanthus is in Justicieae, Tetramerium lineage, and the remaining enigmatic genera are in Whitfieldieae or Barlerieae, and Andrographideae are sister to Barlerieae. This last result is unanticipated, but placement of Andrographideae based on structural characters has been elusive. Neuracanthus is monophyletic but placement relative to (Whitfieldieae (Andrographideae + Barlerieae)) is weakly supported. Many clades have clear morphological synapomorphies, but nonmolecular evidence for some remains elusive. Results suggest an Old World origin with multiple dispersal events to the New World. This study informs future work by clarifying sampling strategy and identifying aspects of relationships that require further study.  相似文献   
38.
The influence of membrane depolarization on somatostatin secretion and protein synthesis by fetal and neonatal cerebrocortical neurons was studied. Cortical cells obtained by mechanical dispersion were maintained as monolayer cultures for 8 days. The ability of fetal cerebrocortical and hypothalamic cells to release immunoreactive somatostatin (IR-SRIF) was confirmed. Total protein synthesis was determined by the incorporation of [3H]phenylalanine into trichloroacetic acid-precipitable proteins. To study the effect of acute depolarization on protein synthesis, cells were incubated for 30 min with [3H]phenylalanine or [3H]leucine and the depolarizing agent. In fetal cerebrocortical cells, potassium (30 and 56 mM) decreased protein synthesis and RNA levels and increased IR-SRIF release. Depolarization by veratridine, a sodium channel activator, induced a similar effect. The effect of veratridine on IR-SRIF and protein synthesis was reversed by tetrodotoxin, a sodium channel blocker, or verapamil, a calcium channel blocker. These findings suggest that protein synthesis by cerebrocortical cells is decreased in fetal brain cells by membrane depolarization and is dependent on Na+ and Ca2+ entry into cells. In postnatal (day 7) cerebrocortical cells, depolarization induced by high potassium concentrations led to a concomitant increase in protein synthesis, RNA content, and somatostatin release. These findings indicate that depolarization of the cellular membrane is coupled to an increase in protein synthesis in neonatal, but not in fetal, dispersed brain cells.  相似文献   
39.
Rhynchocyon udzungwensis is a recently described and poorly understood sengi (giant elephant-shrew) endemic to two small montane forests in Southern Tanzania, and surrounded in lower forests by R. cirnei reichardi. In this study, we investigate the molecular genetic relationship between R. udzungwensis and R. c. reichardi, and the possible role that shifting species distributions in response to climate fluctuations may have played in shaping their evolutionary history. Rhynchocyon udzungwensis and R. c. reichardi individuals were sampled from five localities for genetic analyses. Three mitochondrial and two nuclear loci were used to construct species trees for delimitation and to determine whether introgression was detectable either from ancient or ongoing hybridization. All species-tree results show R. udzungwensis and R. c. reichardi as distinct lineages, though mtDNA shows evidence of introgression in some populations. Nuclear loci of each species were monophyletic, implying introgression is exclusively historical. Because we found evidence of introgression, we used distribution data and species distribution modelling for present, glacial, and interglacial climate cycles to predict how shifting species distributions may have facilitated hybridization in some populations. Though interpretations are affected by the limited range of these species, a likely scenario is that the mtDNA introgression found in eastern mid-elevation populations was facilitated by low numbers of R. udzungwensis that expanded into lowland heavily occupied R. c. reichardi areas during interglacial climate cycles. These results imply that relationships within the genus Rhynchocyon may be confounded by porous species boundaries and introgression, even if species are not currently sympatric.  相似文献   
40.
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