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21.
A patient with scleroderma who presented with pericarditis and effusion is described. Aspirates from this pericardial effusion had the characteristics of an exudate with no evidence of autoantibodies, immune complexes or complement depletion. These findings suggest that the mechanisms operating in the production of pericardial effusion in scleroderma may be different from those found in rheumatoid arthritis and systemic lupus erythematosus.  相似文献   
22.

Background

Liver steatosis is associated with poor outcome after liver transplantation and liver resection. There is a need for an accurate and reliable intraoperative tool to identify and quantify steatosis. This study aimed to investigate whether surface diffuse reflectance spectroscopy (DRS) measurements could detect liver steatosis on humans during liver surgery.

Methods

The DRS instrumentation setup consists of a computer, a high-power tungsten halogen light source and two spectrometers, connected through a trifurcated optical fiber to a hand-held probe. Patients scheduled for open resection for liver tumors were considered for inclusion. Multiple DRS measurements were performed on the liver surface after mobilization.

Results

In total, 1210 DRS spectra originated from 38 patients, were analyzed. When applying the data to an analytical model the volumetric absorption ratio factor of fat and water specified an explicit distinction between mild to moderate, and moderate to severe steatosis (p < 0.001). There were significant differences between none-to-mild and moderate-to-severe steatosis grade for the following parameters: reduced scattering coefficient (p < 0.001), Mie to total scattering fraction (p < 0.001), Mie slope (p = 0.003), lipid/(lipid + water) (p < 0.001), blood volume (p = 0.044) and bile volume (p < 0.001).

Conclusion

This study shows that it is possible to evaluate steatosis grades with hepatic surface diffuse reflectance spectroscopy measurements.  相似文献   
23.
Summary The relationship between the blood flow pattern immediately following coronary artery occlusion and the resulting infarct 24 hours later was studied in dogs treated with isoproterenol (0.5 g/kg/min for 2 hours) or with propranolol (2mg/kg every 6 hours). The coronary artery of a closed chest dog was perfused via a special cannula with arterial blood. A 2-mm diameter plastic bead was introduced into the perfusate to embolize a coronary branch. One minute after occlusion, radiolabelled microspheres were injected into the perfusate. The dogs were then allowed to recover. 24 hours later the dogs were reanesthetized and their hearts removed. The hearts were sliced into 4 mm thick sections and the microsphere distribution was visualized by autoradiography of the tissue. Superimposition of developed autoradiographs and tracings of the infarct pattern of stained sections allowed direct comparison of the blood flow pattern immediately after occlusion to the eventual pattern of infarction. In all 8 control dogs, all 6 isoproterenol dogs and all 12 propranolol dogs the lateral borders of blood flow and infarction were superimposable indicating no lateral change in infarct size resulting from treatment. In the control group there was a subepicardial region of the ischemic zone which did not infarct (15.2±2.3% of the ischemic zone). Though isoproterenol did not significantly change the size of this zone, propranolol increased it to 35.9±6,5% (p<0.005) indicating vertical but not lateral salvage.Supported by Grant HL-20648 from NIH: HLBI and a Grant-in-aid from the American Heart Association and with funds contributed in part by the Northwest Ohio Chapter, Inc.  相似文献   
24.
Twenty-seven patients with hypertension were randomly allocated to a 10 month crossover study. Treatment consisted of spironolactone (200 mg/day for 2 months), propranolol (320 mg/day for 2 months) and combined administration of both drugs at half the dosage. Between treatment periods placebo was given for 2 months. Fourteen patients were previously untreated. The average pretreatment blood pressure for the entire group was 188/114 ± 16/7 (mean ± standard deviation) mm Hg supine and 188/118 ± 20/9 mm Hg standing. Both spironolactone and propranolol reduced blood pressure significantly in both the supine and standing positions.Upright plasma renin activity was determined by radioimmunoassay of angiotensin I. The average initial level was 1.9 ± 1.2 (range 0.4 to 5.0) ng/ml/hr. There was a close correlation between plasma renin activity and the effects of the drugs: With increasing renin level the response to propranolol was better whereas the opposite was true for spironolactone. The combination of spironolactone and propranolol decreased the blood pressure still further in the supine and standing positions, irrespective of initial plasma renin activity. All patients achieved a normal supine pressure. Blood pressure and plasma renin activity returned toward pretreatment values during placebo administration. It is concluded that pretreatment levels of plasma renin activity can predict the antihypertensive response to propranolol and spironolactone. The combination of the two drugs, which have different modes of action, will effectively reduce blood pressure in hypertension. The results support the concept that the renin-angiotensin-aldosterone system may be involved in primary hypertension.  相似文献   
25.
The frontal ganglion of the adult forms of the tobacco hornworm, Manduca sexta, was investigated immunocytochemically for the occurrence of the gastro-entero-pancreatic (GEP) neurohormonal peptides, namely insulin, nerve growth factor, epidermal growth factor, insulin C-peptide, somatostatin, glucagon, glicentin, pancreatic polypeptide (PP), polypeptide YY (PYY), secretin, vasoactive intestinal peptide (VIP), gastric inhibitory peptide (GIP), gastrin, cholecystokinin (CCK), enkephalin, alpha- and beta-endorphins, substance P, neurotensin, bombesin, motilin, ACTH, serotonin, and calcitonin. Among all the antisera tested, positive immunostaining was obtained with anti-insulin B-chain serum only. The insulin B-chain immunoreactivity was localized in 4-6 large (30-40 microns) neurons, in the neuropile, and in the recurrent nerve. It is speculated that the insulin-like immunoreactive material may be transported to the neurohaemal organ (corpora cardiaca) through the nervi cardiaco-somatogastrici.  相似文献   
26.
Pluronics have been demonstrated as excellent multidrug resistance (MDR) reversal agent in the form of unimers rather than micelles. However, the effective intracellular delivery of Pluronic® unimers to MDR cancer cells still remains a big challenge. To address this issue, a mixed micellar system based mainly on the pH-sensitive copolymer of poly (l-histidine)-poly (d,l-lactide)-polyethyleneglycol-poly (d,l-lactide)-poly (l-histidine) (PHis-PLA-PEG-PLA-PHis) and Pluronic® F127, some of which was conjugated with folate, was constructed to intracellularly deliver the unimers of Pluronic® P85 to MDR cells. The folate-mediated endosomal pH-sensitive mixed micelles (pHendoSM-P85/f) were prepared by a thin-film hydration method, by which Pluronic® P85 unimers and doxorubicin (DOX) were incoporated into the mixed micelles. The incorporation of Pluronic® P85 unimers was investigated by the surface tension test. The results indicated that the Pluronic® P85 unimers probably first inserted into the binary mixed micelles and then formed a triple-component mixed micelles with Pluronic® F127 and PHis-PLA-PEG-PLA-PHis as the loading content increased. Further analyzed with flow cytometry, confocal laser scanning microscopy (CLSM) and MTT assay, the micelles with inserted Pluronic® P85 unimers demonstrated much more cellular uptake and higher cytotoxicity against MDR cells than the triple-component mixed micelles and plain Pluronic® micelles. The enhanced MDR reversal effect was attributed to the successful intracellular delivery of Pluronic® P85 unimers to the MDR cells, which was confirmed by the subcellular colocalization of Pluronic® P85 unimers with mitochondria, the decreased ATP energy and mitochondrial membrane potential (MP) in the MCF-7/ADR cells. The pHendoSM-P85/f/DOX also demonstrated more dramatic antitumor efficiency and remarkable reduction of ATP energy in the MDR cells in tumors than the control formulations. The intracellular delivery of Pluronic® P85 unimers to the MDR cells based on the targeted and endosomal pH triggerd release mixed micelles has been demonstrated as a promising approach to reverse MDR.  相似文献   
27.
Pure hair and nail ectodermal dysplasia (PHNED) is a rare genetic disorder characterized by hypotrichosis or complete alopecia, as well as nail dystrophy. Mutations in the type II hair keratin gene KRT85 and the HOXC13 gene on chromosome 12q have recently been identified in families with autosomal‐recessive PHNED. In the present study, we have analyzed a consanguineous Syrian family with an affected girl having complete alopecia and nail dystrophy since birth. The family clearly showed linkage to chromosome 12q13.13–12q14.3, which excluded the KRT85 gene. Sequencing of another candidate gene HOXC13 within the linkage interval identified a homozygous frameshift mutation (c.355delC; p.Leu119Trpfs*20). Expression studies in cultured cells revealed that the mutant HOXC13 protein mislocalized within the cytoplasm, and failed to upregulate the promoter activities of its target genes. Our results strongly suggest crucial roles of the HOXC13 gene in the development of hair and nails in humans.  相似文献   
28.
We have identified a deletion of 3 base pairs in the dystrophin gene (DMD), c.9711_9713del, in a family with nonspecific X-linked intellectual disability (ID) by sequencing of the exons of 86 known X-linked ID genes. This in-frame deletion results in the deletion of a single-amino-acid residue, Leu3238, in the brain-specific isoform Dp71 of dystrophin. Linkage analysis supported causality as the mutation was present in the 7.6 cM linkage interval on Xp22.11–Xp21.1 with a maximum positive LOD score of 2.41 (MRX85 locus). Molecular modeling predicts that the p.(Leu3238del) deletion results in the destabilization of the C-terminal domain of dystrophin and hence reduces the ability to interact with β-dystroglycan. Correspondingly, Dp71 protein levels in lymphoblastoid cells from the index patient are 6.7-fold lower than those in control cell lines (P=0.08). Subsequent determination of the creatine kinase levels in blood of the index patient showed a mild but significant elevation in serum creatine kinase, which is in line with impaired dystrophin function. In conclusion, we have identified the first DMD mutation in Dp71 that results in ID without muscular dystrophy.  相似文献   
29.
We present a child case of heterotaxy syndrome (asplenia syndrome) after Fontan procedure that showed extreme prolongation of QT interval and torsade de pointes (TdP) after administration of sodium channel blockers for paroxysmal atrial tachycardia. Despite low serum concentration of the drugs, QT prolongation persisted and TdP attacks with unconsciousness recurred, possibly in association with junctional bradycardia and myocardial damage although he had never experienced QT prolongation during bradycardia before. Temporal cardiac pacing via a venous route to exclude possible implication of bradycardia in induction of TdP was difficult to apply due to total cavopulmonary connection (TCPC) circulation. Continuous intravenous administration of low-dose isoproterenol was started but an appropriate heart rate for prevention of TdP was difficult to obtain. Finally, we were urged to conduct implantation of a DDD pacemaker combined with ICD surgically with epicardial leads, resulting in successful suppression of TdP and syncope. Screening of the genotype disclosed the KCNE1 D85N polymorphism, which is known as one of the typical disease-causing gene variants in long-QT syndrome (LQTS).  相似文献   
30.
Purpose: The correlation between the presence of specific gene sequence of M. tuberculosis and specific diagnosis of clinical tuberculosis is not known. This study compared the results of polymerase chain reaction (PCR) amplification of M. tuberculosis specific DNA sequences (IS6110, 65kDa, 38kDa and mRNA coding for 85 B protein) from different clinical samples of pulmonary and extrapulmonary tuberculosis. Methods: One hundred and seventy-two clinical samples from suspected tuberculosis patients were tested for smear examination, culture (LJ and rapid BACTEC 460 TB system) and PCR. PCR was performed with specific primers for the targets: IS6110, 65kDa, 38kDa and 85B. Results: Each PCR test was found to have a much higher positivity than conventional test and BACTEC culture (P 0.05). Smear positive samples (56) and the samples (36) showing positive results by conventional methods (smear and LJ medium culture) and BACTEC were found to be positive by all PCR protocols. No significant difference was found between the four PCR protocols (P >0.05). The primer specific for amplifying the 123bp IS6110 fragment gave the highest positivity (83%), followed by 65kDa, 38kDa and 85B RT-PCR in descending order. Conclusions: These data suggest that the presence of IS6110 correlates more closely with the diagnosis of clinical tuberculosis than that of 65kDa, 38kDa and 85B  相似文献   
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