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21.
Objective: Pulmonary endarterectomy (PEA) is the standard therapy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). In the immediate postoperative period, persistent pulmonary hypertension increases the risk of acute respiratory or right heart failure. In pulmonary arterial hypertension, prostanoid inhalation has been found to improve pulmonary hemodynamics, right ventricular function, gas exchange, and clinical outcome. We report the results of a double-blinded randomized trial with the aerosolized prostacyclin analogue iloprost in patients with residual pulmonary hypertension after PEA. Methods: Twenty-two patients (age, 55 ± 13 years; 8 females; propofol- and sufentanil-based anesthesia; pressure-controlled mechanical ventilation) were randomized to receive either a single dose of 25 μg aerosolized iloprost (iloprost group; n = 11) or normal saline (placebo group; n = 11) immediately after postoperative ICU admission. Primary endpoints were changes in gas exchange, pulmonary and systemic hemodynamics, and clinical outcome. Results: Iloprost significantly enhanced cardiac index (CI) and reduced mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance [PVR (dyn s cm−5)] in contrast to placebo. Placebo: pre-inhalation 413 ± 195 versus post-inhalation 404 ± 196 at 30 min (p = 0.051), 415 ± 189 at 90 min (p = 0.929). Iloprost: pre-inhalation 503 ± 238 versus post-inhalation 328 ± 215 at 30 min (p = 0.001), 353 ± 156 at 90 min (p = 0.003). Blood oxygenation remained unchanged. Conclusion: In addition to the effect of PEA, iloprost reduces residual postoperative pulmonary hypertension, decreases right ventricular afterload and may facilitate the early postoperative management after PEA.  相似文献   
22.
Microalbuminuria, an early feature of diabetic nephropathy, indicates intrarenal endothelial damage. In type 2 diabetes, microalbuminuria is strongly related to insulin resistance. We therefore investigated whether rosiglitazone, an insulin-sensitizing drug that is known to improve endothelial dysfunction, was able to improve intrarenal endothelial dysfunction and microalbuminuria. Nineteen type 2 diabetic patients participated in this double-blind cross-over trial. Nine patients with newly diagnosed disease without microalbuminuria were randomized to a treatment with rosiglitazone or nateglinide, each for 12 weeks. Ten patients with microalbuminuria were randomized to rosiglitazone or placebo, each for 12 weeks in addition to their previous antidiabetic medication. After each treatment, glomerular filtration rate (GFR), renal plasma flow, and filtration fraction were measured before and after blockade of nitric oxide (NO) by intravenous administration of N-monomethyl-L-arginine-acetate (L-NMMA). Ten healthy subjects served as control subjects. Type 2 diabetic patients at baseline showed glomerular hyperfiltration compared with healthy control subjects. Rosiglitazone reduced elevated GFR and filtration fraction toward control primarily in patients with microalbuminuria (GFR: 133.4 +/- 9.8 vs. 119.6 +/- 8.7 ml/min; filtration fraction: 23.2 +/- 1.7 vs. 20.5 +/- 1.6% before and after rosiglitazone, respectively; control subjects: GFR 111.7 +/- 8.6 ml/min, filtration fraction 20.4 +/- 1.5%). Rosiglitazone improved intrarenal NO bioavailability in type 2 diabetes toward control as shown by infusion of L-NMMA. Rosiglitazone reduced albumin excretion in type 2 diabetes with microalbuminuria from 116.5 +/- 31 to 40.4 +/- 12 mg/day. Rosiglitazone ameliorated glomerular hyperfiltration in early type 2 diabetes, improved NO bioavailability, and lessened renal end-organ damage in type 2 diabetes with microalbuminuria.  相似文献   
23.
Isolated TSH deficiency is a rare cause of congenital hypothyroidism. We here report four children from two consanguineous Turkish families with isolated TSH deficiency. Affected children who were screened at newborn age had an unremarkable TSH result and a low serum TSH level at diagnosis. Age at diagnosis and clinical phenotype were variable. All affected children carried an identical homozygous splice site mutation (IVS2 + 5 G--> A) in the TSHbeta gene. This mutation leads to skipping of exon 2 and a loss of the translational start codon without ability to produce a TSH-like protein. However, using specific monoclonal antibodies, we detected a very low concentration of authentic, heterodimeric TSH in serum, indicating the production of a small amount of correctly spliced TSH mRNA. By genotyping all family members with polymorphic markers at the TSHbeta locus, we show that the mutation arose on a common ancestral haplotype in three unrelated Turkish families indicating a founder mutation in the Turkish population. These results suggest that this TSHbeta mutation is among the more common TSHbeta gene mutations and stress the need for a biochemical and molecular genetic workup in children with symptoms suggestive of congenital hypothyroidism, even when the neonatal TSH screening is normal.  相似文献   
24.
Muta  Hiromi  Podack  Eckhard R. 《Immunologic research》2013,57(1-3):151-158
Immunologic Research - The FDA recently approved an agonistic anti-CD30 drug conjugate, Brentuximab vedotin, for the treatment for CD30-positive lymphomas. The potent clinical activity of...  相似文献   
25.
Yersinia enterocolitica is a human pathogen that is ubiquitous in livestock, especially pigs. The bacteria are able to colonize the intestinal tract of a variety of mammalian hosts, but the severity of induced gut-associated diseases (yersiniosis) differs significantly between hosts. To gain more information about the individual virulence determinants that contribute to colonization and induction of immune responses in different hosts, we analyzed and compared the interactions of different human- and animal-derived isolates of serotypes O:3, O:5,27, O:8, and O:9 with murine, porcine, and human intestinal cells and macrophages. The examined strains exhibited significant serotype-specific cell binding and entry characteristics, but adhesion and uptake into different host cells were not host specific and were independent of the source of the isolate. In contrast, survival and replication within macrophages and the induced proinflammatory response differed between murine, porcine, and human macrophages, suggesting a host-specific immune response. In fact, similar levels of the proinflammatory cytokine macrophage inflammatory protein 2 (MIP-2) were secreted by murine bone marrow-derived macrophages with all tested isolates, but the equivalent interleukin-8 (IL-8) response of porcine bone marrow-derived macrophages was strongly serotype specific and considerably lower in O:3 than in O:8 strains. In addition, all tested Y. enterocolitica strains caused a considerably higher level of secretion of the anti-inflammatory cytokine IL-10 by porcine than by murine macrophages. This could contribute to limiting the severity of the infection (in particular of serotype O:3 strains) in pigs, which are the primary reservoir of Y. enterocolitica strains pathogenic to humans.  相似文献   
26.
Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene)s (PPE‐PPVs) with various thiophene units (thiophene, bithiophene, and 3,4‐ethylenedioxythiophene) at the X position, with the general backbone design (Ph? C?C? X ? C?C? Ph? CH?CH? Ph? CH?CH? ), bearing identical solubilizing side chains at the phenylene rings of the polymers, are synthesized to study the effect of this structural alteration on the properties such as the photophysics, the electrochemical properties, the charge‐carrier mobility, and the morphology of the materials and its impact on their photovoltaic performance. The polymers are obtained in good yields with reasonable molecular weights and show solubility in ordinary organic solvents required for solution‐processing applications. The polymer with a basic thiophene ring at the X positions shows the highest open‐circuit voltage (VOC of 930 mV) and the polymer with a bithiophene unit at the X position shows the highest short‐circuit current density and charge‐carrier mobility, whereas the polymer with 3,4‐ethylenedioxythiophene shows the lowest photovoltaic performance.

  相似文献   

27.
We analyzed two mutant mouse lines, ATE1 and ATE2, that carry point mutations in the enamelin gene which result in premature stop codons in exon 8 and exon 7, respectively. Both mutant lines show amelogenesis imperfecta. To establish the effect of mutations within the enamelin gene on different organs, we performed a systematic, standardized phenotypic analysis of both mutant lines in the German Mouse Clinic. In addition to the initially characterized tooth phenotype that is present in both mutant lines, we detected effects of enamelin mutations on bone and energy metabolism, as well as on clinical chemical and hematological parameters. These data raise the hypothesis that enamelin defects have pleiotropic effects on organs other than the teeth.  相似文献   
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