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51.

Background  

Smoking cessation interventions in pregnancy could influence a woman's social behaviour and her partner's smoking behaviour, but this has not been examined in any published randomized trials.  相似文献   
52.
Toll-like receptor 9 (TLR9) modulators have potent Th1-adjuvant activity. We recently reported the development of immunomodulatory oligonucleotides (IMOs) containing novel structures (immunomers) and synthetic immunostimulatory CpR (R=2'-deoxy-7-deazguanosine) or R'pG (R'=1-(2'-deoxy-beta-D-ribofuranosyl)-2-oxo-7-deaza-8-methyl-purine) motifs. IMOs activate TLR9 pathways, resulting in cytokine secretion profiles different from those induced by CpG DNA. In the present study we evaluated the adjuvant activity of IMOs containing CpG, CpR, or R'pG motifs in combination with hepatitis B surface antigen (HBsAg) in a mouse model. Mice immunized with HBsAg plus IMO produced higher levels of IgG2a and lower levels of IgG1 than did mice immunized with HBsAg alone or with alum. High IgG2a responses were found at week 4 and remained high until 14 weeks after immunization. Adoptive transfer of splenocytes from HBsAg/IMO-immunized mice to na?ve mice resulted in strong IgG2a production in response to antigen boost. Splenocytes of mice immunized with HBsAg/IMO produced high levels of IFN-gamma, but not Th2 cytokines IL-4 and IL-5, in antigen-recall experiments in vitro. The use of IMOs as adjuvants to HBsAg resulted in the production of strong anti-HBsAg antibodies at antigen doses as low as 0.2 microg. These data demonstrate that IMOs enhance the immunogenicity of HBsAg through potent Th1 immune responses, which may allow lower doses of antigen in vaccination.  相似文献   
53.
Delivery to the CNS via the nasal cavity has been pursued as a means to circumvent the blood-brain barrier (BBB), yet the mechanism of drug transport across this novel route is not well understood. Hydroxyzine and triprolidine have been reported to readily reach the CNS following nasal administration, whereas no measurable amounts of chlorcyclizine or chlorpheniramine, structurally similar antihistamines, were observed in the CSF. The permeation of chlorpheniramine and chlorcyclizine in vitro across the bovine olfactory mucosa was studied to investigate the biological and physicochemical characteristics that contribute to the limited CNS disposition of these compounds following nasal administration. The submucosal to mucosal fluxes (J(s-m)) of chlorcyclizine and chlorpheniramine across the olfactory mucosa were significantly greater than the mucosal to submucosal fluxes (J(m-s)). Moreover, the submucosal-mucosal permeability of both compounds was temperature dependent and saturable. In the presence of metabolic inhibitors (ouabain and 2,4-dinitrophenol) and P-glycoprotein (P-gp)/multidrug resistance protein 1 (MRP1) inhibitors (quinidine and verapamil), the J(m-s) increased and J(s-m) decreased significantly. These results indicate that chlorpheniramine and chlorcyclizine are effluxed from the olfactory mucosa by efflux transporters such as P-gp and MRP1. Transport studies across inert polymeric membranes demonstrated that the permeability of chlorpheniramine and chlorcyclizine decreased at donor concentrations higher than 3 mM suggesting that physicochemical properties such as self-aggregation also play a role in the reduced olfactory mucosal permeability of these compounds at higher concentrations.  相似文献   
54.

Background:

There have been an increasing number of reports world-wide relating improved outcomes after pancreatic resections to high volumes thereby supporting the idea of centralization of pancreatic resectional surgery. To date there has been no collective attempt from India at addressing this issue. This cohort study analysed peri-operative outcomes after pancreatoduodenectomy (PD) at seven major Indian centres.

Materials and Methods:

Between January 2005 and December 2007, retrospective data on PDs, including intra-operative and post-operative factors, were obtained from seven major centres for pancreatic surgery in India.

Results:

Between January 2005 and December 2007, a total of 718 PDs were performed in India at the seven centres. The median number of PDs performed per year was 34 (range 9–54). The median number of PDs per surgeon per year was 16 (range 7–38). Ninety-four per cent of surgeries were performed for suspected malignancy in the pancreatic head and periampullary region. The median mortality rate per centre was four (range 2–5%). Wound infections were the commonest complication with a median incidence per centre of 18% (range 9.3–32.2%), and the median post-operative duration of hospital stay was 16 days (range 4–100 days).

Conclusions:

This is the first multi-centric report of peri-operative outcomes of PD from India. The results from these specialist centers are very acceptable, and appear to support the thrust towards centralization.  相似文献   
55.

Background

Medical intelligence of disease vectors deals with understanding vector distribution and control.

Methods

An entomological baseline survey using standard vector sampling techniques was done as a pilot study to map the vectors of defence importance in two cantonments of Pune with a view to establish a vector databank and impart training to armed forces personnel in vector surveillance.

Result

The project trained 142 armed forces personnel in surveillance techniques in three years. Seventeen species of mosquitoes comprising of eight vector species were collected. Three other vectors viz. Rhipicephalus sanguineus, Xenopsylla cheopis and Leptotrombidium deliense are reported.

Conclusion

The study emphasizes the need for vector mapping /surveillance in each area for preventing morbidity and mortality amongst troops. It also focuses on indigenous fabrication of vector sampling tools and training of personnel for capacity building which in turn will enable such surveys to be undertaken in other units and deployment areas.Key Words: Leptotrombidium, Mosquitoes, Rhipicephalus, Surveillance, Xenopsylla  相似文献   
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58.
Oligonucleotides are being employed for gene-silencing activity by a variety of mechanisms, including antisense, ribozyme, and siRNA. In the present studies, we designed novel oligonucleotides complementary to targeted mRNAs and studied the effect of 3'-end exposure and oligonucleotide length on gene-silencing activity. We synthesized both oligoribonucleotides (RNAs) and oligodeoxynucleotides (DNAs) with phosphorothioate backbones, consisting of two identical segments complementary to the targeted mRNA attached through their 5'-ends, thereby containing two accessible 3'-ends; these compounds are referred to as gene-silencing oligonucleotides (GSOs). RNA and/or DNA GSOs targeted to MyD88, VEGF, and TLR9 mRNAs had more potent gene-silencing activity than did antisense phosphorothioate oligonucleotides (PS-oligos) in cell-based assays and in vivo. Of the different lengths of GSOs evaluated, 19-mer long RNA and DNA GSOs had the best gene-silencing activity both in vitro and in vivo. These results suggest that GSOs are novel agents for gene silencing that can be delivered systemically with broader applicability.  相似文献   
59.
Dichlorvos is a synthetic insecticide that belongs to the family of chemically related organophosphate (OP) pesticides. It can be released into the environment as a major degradation product of other OPs, such as trichlorfon, naled, and metrifonate. Dichlorvos exerts its toxic effects in humans and animals by inhibiting neural acetylcholinesterase. Chronic low-level exposure to dichlorvos has been shown to result in inhibition of the mitochondrial complex I and cytochrome oxidase in rat brain, resulting in generation of reactive oxygen species (ROS). Enhanced ROS production leads to disruption of cellular antioxidant defense systems and release of cytochrome c (cyt c) from mitochondria to cytosol resulting in apoptotic cell death. MitoQ is an antioxidant, selectively targeted to mitochondria and protects it from oxidative damage and has been shown to decrease mitochondrial damage in various animal models of oxidative stress. We hypothesized that if oxidative damage to mitochondria does play a significant role in dichlorvos induced neurodegeneration, then MitoQ should ameliorate neuronal apoptosis. Administration of MitoQ (100 μmol/kg body wt/day) reduced dichlorvos (6 mg/kg body wt/day) induced oxidative stress (decreased ROS production, increased MnSOD activity and glutathione levels) with decreased lipid peroxidation, protein and DNA oxidation. In addition, MitoQ also suppressed DNA fragmentation, cyt c release and caspase-3 activity in dichlorvos treated rats compared to the control group. Further electron microscopic studies revealed that MitoQ attenuates dichlorvos induced mitochondrial swelling, loss of cristae and chromatin condensation. These results indicate that MitoQ may be beneficial against OP (dichlorvos) induced neurodegeneration.  相似文献   
60.
Alzheimer's disease amyloid β (Aβ) proteins accumulate in the cerebral vasculature and cause cerebral amyloid angiopathy (CAA). The objective of this study was to resolve critical formulation issues in developing nanoparticles (NPs) capable of permeating the blood brain barrier (BBB) and targeting cerebrovascular Aβ proteins. To achieve this objective we designed immuno-nanovehicles, which are chitosan-coated poly lactic-co-glycolic acid (PLGA) NPs conjugated with a novel anti-Aβ antibody. Measurements made according to Derjaguin-Landau-Verwey-Overbeek (DLVO) theory indicated that the immuno-nanovehicles have a much lower propensity to aggregate than the control nanovehicles. Immuno-nanovehicles showed enhanced uptake at the BBB and better targeting of the Aβ proteins deposited in the CAA model in vitro in comparison with the control nanovehicles. In addition, chitosan enhanced aqueous dispersibility and increased the stability of immuno-nanovehicles during lyophilization, thus transforming them into ideal vehicles for delivering therapeutic and diagnostic agents to the cerebral vasculature ridden with vascular amyloid. FROM THE CLINICAL EDITOR: In this study, the authors report the development of chitosan-coated PLGA nanoparticles conjugated with anti-amyloid antibody to be used as immuno-nanovehicles to image cerebral amyloid angiopathy deposits in vivo. This method enables delivering therapeutic and diagnostic agents to the cerebral vasculature ridden with vascular amyloid.  相似文献   
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