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941.

Background

Congestive physical findings such as pulmonary rales and third heart sound (S3) are hallmarks of acute heart failure (AHF). However, their role in outcome prediction remains unclear. We sought to investigate the association between congestive physical findings upon admission, steady-state biomarkers at the time of discharge, and long-term outcomes in AHF patients.

Methods

We analyzed the data of 133 consecutive AHF patients with an established diagnosis of ischemic or non-ischemic (dilated or hypertrophic) cardiomyopathy, admitted to a single-center university hospital between 2006 and 2010. The treating physician prospectively recorded major symptoms and congestive physical findings of AHF: paroxysmal nocturnal dyspnea, orthopnea, pulmonary rales, jugular venous distension (JVD), S3, and edema. The primary endpoint was defined as rehospitalization for HF.

Results

Majority (63.9%) of the patients had non-ischemic etiology and, at the time of admission, S3 was seen in 69.9% of the patients, JVD in 54.1%, and pulmonary rales in 43.6%. The mean follow-up period was 726 ± 31days. Patients with pulmonary rales (p < 0.001) and S3 (p  =  0.011) had worse readmission rates than those without these findings; the presence of these findings was also associated with elevated troponin T (TnT) levels at the time of discharge (odds ratio [OR] 2.8; p  =  0.02 and OR 2.6; p  =  0.05, respectively).

Conclusion

Pulmonary rales and S3 were associated with inferior readmission rates and elevated TnT levels on discharge. The worsening of the readmission rate owing to congestive physical findings may be a consequence of on-going myocardial injury.  相似文献   
942.

Purpose

Since matrix metalloproteinase-2 (MMP-2) is an important marker of tumor malignancy, we developed an original drug design strategy, MMP-2 activity dependent anchoring probes (MDAP), for use in MMP-2 activity imaging, and evaluated the usefulness of this probe in in vitro and in vivo experiments.

Methods

We designed and synthesized MDAP1000, MDAP3000, and MDAP5000, which consist of 4 independent moieties: RI unit (111In hydrophilic chelate), MMP-2 substrate unit (short peptide), anchoring unit (alkyl chain), and anchoring inhibition unit (polyethylene glycol (PEGn; where n represents the approximate molecular weight, n = 1000, 3000, and 5000). Probe cleavage was evaluated by chromatography after MMP-2 treatment. Cellular uptake of the probes was then measured. Radioactivity accumulation in tumor xenografts was evaluated after intravenous injection of the probes, and probe cleavage was evaluated in tumor homogenates.

Results

MDAP1000, MDAP3000, and MDAP5000 were cleaved by MMP-2 in a concentration-dependent manner. MDAP3000 pretreated with MMP-2 showed higher accumulation in tumor cells, and was completely blocked by additional treatment with an MMP inhibitor. MDAP3000 exhibited rapid blood clearance and a high tumor accumulation after intravenous injection in a rodent model. Furthermore, pharmacokinetic analysis revealed that MDAP3000 exhibited a considerably slow washout rate from tumors to blood. A certain fraction of cleaved MDAP3000 existed in tumor xenografts in vivo.

Conclusions

The results indicate the possible usefulness of our MDAP strategy for tumor imaging.  相似文献   
943.

Objective

An Asian dust storm (ADS) contains airborne particles that affect conditions such as asthma, but the mechanism of exacerbation is unclear. The objective of this study was to compare immune adjuvant effects and airway inflammation induced by airborne particles collected on ADS days and the original ADS soil (CJ-1 soil) in asthma model mice.

Methods

Airborne particles were collected on ADS days in western Japan. NC/Nga mice were co-sensitized by intranasal instillation with ADS airborne particles and/or Dermatophagoides farinae (Df), and with CJ-1 soil and/or Df for 5 consecutive days. Df-sensitized mice were stimulated with Df challenge intranasally at 7 days after the last Df sensitization. At 24 hours after challenge, serum allergen specific antibody, differential leukocyte count and inflammatory cytokines in bronchoalveolar lavage fluid (BALF) were measured, and airway inflammation was examined histopathologically.

Results

Co-sensitization with ADS airborne particles and Df increased the neutrophil and eosinophil counts in BALF. Augmentation of airway inflammation was also observed in peribronchiolar and perivascular lung areas. Df-specific serum IgE was significantly elevated by ADS airborne particles, but not by CJ-1 soil. Levels of interleukin (IL)-5, IL-13, IL-6, and macrophage inflammatory protein-2 were higher in BALF in mice treated with ADS airborne particles.

Conclusion

These results suggest that substances attached to ADS airborne particles that are not in the original ADS soil may play important roles in immune adjuvant effects and airway inflammation.  相似文献   
944.

Objective

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is currently classified into clinical subtypes, including typical and atypical forms (multifocal acquired demyelinating sensory and motor neuropathy (MADSAM) and distal acquired demyelinating symmetric neuropathy (DADS)). The aim of this study was to elucidate the patterns and severity of breakdown of the blood-nerve barrier (BNB) in each CIDP subtype.

Methods

We evaluated the effects of sera obtained from patients with typical CIDP, MADSAM and DADS and control subjects on the expression levels of tight junction proteins and transendothelial electrical resistance (TEER) value in human peripheral nerve microvascular endothelial cells (PnMECs).

Results

The sera obtained from the patients with the three clinical phenotypes of CIDP decreased the amount of claudin-5 protein levels and TEER values in the PnMECs. In addition, the sera obtained from typical CIDP patients more prominently reduced claudin-5 protein levels and TEER values in the PnMECs than did that obtained from the MADSAM and DADS patients. Furthermore, the severity of BNB disruption after exposure to the sera was associated with higher Hughes grade, lower MRC score, more pronounced slowing of motor nerve conduction in the median nerve and higher frequency of abnormal temporal dispersion.

Conclusions

Sera derived from typical CIDP patients destroy the BNB more severely than those from MADSAM or DADS patients. The extent of BNB disruption in the setting of CIDP is associated with clinical disability and demyelination in the nerve trunk. These observations may explain the phenotypical differences between CIDP subtypes.  相似文献   
945.
946.
Many epidemiologic studies have suggested that diabetes may be an important risk factor for periodontal disease. To determine whether diabetes induces or enhances periodontal disease or dental caries, dental tissue from diabetic male and nondiabetic female WBN/KobSlc rats and male and female age-matched nondiabetic F344 rats was analyzed morphologically and morphometrically for these 2 types of lesions. Soft X-ray examination revealed that the incidence and severity of both molar caries and alveolar bone resorption were much higher in male WBN/KobSlc rats with chronic diabetes than in nondiabetic female rats of the same strain. Histopathologic examination showed that dental caries progressed from acute to subacute inflammation due to bacterial infections and necrosis in the pulp when the caries penetrated the dentin. In the most advanced stage of dental caries, inflammatory changes caused root abscess and subsequent apical periodontitis, with the formation of granulation tissue around the dental root. Inflammatory changes resulted in resorption of alveolar bone and correlated well with the severity of molar caries. Our results suggest that diabetic conditions enhance dental caries in WBN/KobSlc rats and that periodontal lesions may result from the apical periodontitis that is secondary to dental caries.  相似文献   
947.
Mouse embryonic fibroblasts (MEFs) are the most commonly used feeder cells for pluripotent stem cells. However, autogeneic feeder (AF) cells have several advantages such as no xenogeneic risks and reduced costs. In this report, we demonstrate that common marmoset embryonic stem (cmES) cells can be maintained on common marmoset AF (cmAF) cells. These cmES cells were maintained on cmAF cells for 6 months, retaining their morphology, normal karyotype, and expression patterns for the pluripotent markers Oct-3/4, Nanog, SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81, as well as their ability to differentiate into cardiac and neural cells. Antibody array analysis revealed equivalent protein expression profiles between cmES cells maintained on cmAF cells and MEFs. In addition, similarly prepared human embryonic stem (hES) and induced pluripotent stem (hiPS) cell-derived AF cells supported the growth of and maintained the morphology and pluripotent marker expressions of hES and hiPS cells, respectively. DNA microarray analysis revealed that these hES and hiPS cells had mRNA expression profiles similar to those of hES and hiPS cells maintained on MEFs, respectively. Taken together, these findings imply that AF cells can replace MEFs in the routine maintenance of primate pluripotent stem cells.  相似文献   
948.
Insulin and leptin intracellular signaling pathways converge and act synergistically on the hypothalamic phosphatidylinositol-3-OH kinase/3-phosphoinositide-dependent protein kinase 1 (PDK1). However, little is known about whether PDK1 in agouti-related peptide (AGRP) neurons contributes to energy homeostasis. We generated AGRP neuron-specific PDK1 knockout (AGRPPdk1(-/-)) mice and mice with selective expression of transactivation-defective Foxo1 (Δ256Foxo1(AGRP)Pdk1(-/-)). The AGRPPdk1(-/-) mice showed reductions in food intake, body length, and body weight. The Δ256Foxo1(AGRP)Pdk1(-/-) mice showed increased body weight, food intake, and reduced locomotor activity. After four weeks of calorie-restricted feeding, oxygen consumption and locomotor activity were elevated in AGRPPdk1(-/-) mice and reduced in Δ256Foxo1(AGRP)Pdk1(-/-) mice. In vitro, ghrelin-induced changes in [Ca(2+)](i) and inhibition of ghrelin by leptin were significantly attenuated in AGRPPdk1(-/-) neurons compared to control neurons. However, ghrelin-induced [Ca(2+)](i) changes and leptin inhibition were restored in Δ256Foxo1(AGRP)Pdk1(-/-) mice. These results suggested that PDK1 and Foxo1 signaling pathways play important roles in the control of energy homeostasis through AGRP-independent mechanisms.  相似文献   
949.
950.
In this study, we report experimental evidence of the thioautotrophic activity of the epibiotic microbial community associated with the setae of Shinkaia crosnieri, a galatheid crab that is endemic to deep-sea hydrothermal systems in the Okinawa Trough in Japan. Microbial consumption of reduced sulfur compounds under in situ hydrostatic and atmospheric pressure provided evidence of sulfur-oxidizing activity by the epibiotic microbial community; the rate of sulfur oxidation was similar under in situ and decompressed conditions. Results of the microbial consumption of reduced sulfur compounds and tracer experiments using 13C-labeled bicarbonate in the presence and absence of thiosulfate (used as a thioautotrophic substrate) convincingly demonstrated that the epibiotic microbial community on S. crosnieri drove primary production via an energy metabolism that was coupled with the oxidation of reductive sulfur compounds. A combination of tracer experiments, fluorescence in situ hybridization (FISH) and nano-scale secondary ion mass spectrometry (Nano-SIMS) indicated that the filamentous cells of the genus Sulfurovum belonging to the class Epsilonproteobacteria were thioautotrophs in the epibiotic community of S. crosnieri. In conclusion, our results strongly suggest that thioautotrophic production by Sulfurovum members present as the epibiotic microbial community play a predominant role in a probable nutritional ectosymbiosis with S. crosnieri.  相似文献   
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