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61.
Background: Increased leukocyte-endothelial cell interaction (LE) and deterioration of capillary perfusion represent key mechanisms of septic organ dysfunction. The type of volume support, however, which may be used during septic disorders, remains controversial. Using intravital microscopy, the authors studied the effect of different regimens of clinically relevant volume support on endotoxin-induced microcirculatory disorders, including the synthetic colloid hydroxyethyl starch (HES, 130 kD) and a crystalloid regimen with isotonic saline solution (NaCl).

Methods: In Syrian Golden hamsters, normotensive endotoxemia was induced by intravenous application of Escherichia coli lipopolysaccharide (LPS, 2 mg/kg). The microcirculation was analyzed in striated muscle of skinfold preparations. HES 130 kD (Voluven(R), 16 ml/kg, n = 7) or isotonic saline (NaCl, 66 ml/kg, n = 6) were infused 3 h after LPS exposure over a 1-h period (posttreatment mode). Animals receiving LPS without volume therapy served as control subjects (n = 8, control). LE, functional capillary density (FCD), and macromolecular leakage were repeatedly analyzed in the awake animals during a 24-h period using intravital fluorescence microscopy.

Results: HES 130 kD significantly reduced LPS-induced arteriolar and venular leukocyte adherence (P < 0.05), whereas NaCl resuscitation had no effect when compared with nontreated control animals. The LPS-induced decrease in FCD and increase in macromolecular leakage were also significantly attenuated by HES 130 kD but not by NaCl. Improvement of LPS-induced microcirculatory disorders by HES was unlikely the result of macro- and microhemodynamic changes because arterial blood pressure, heart rate, and venular wall shear rate did not differ between HES- and NaCl-treated animals.  相似文献   

62.
Kimura disease is an uncommon chronic inflammatory condition of unknown etiology and is characterized by painless subcutaneous nodules, usually affecting the head and neck, eosinophilia, and markedly elevated immunoglobulin E levels. Several reports have described the main modalities of treatment; both corticosteroids and surgery have provided good results, but occasionally corticosteroids cannot be tapered as the disease flares up. We report here the case of an 8-year-old boy diagnosed with Kimura disease who was successfully treated with 1 dose of intravenous immunoglobulin as a steroid-sparing agent.  相似文献   
63.
Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and is characterized by a progressive accumulation of functionally incompetent monoclonal lymphocytes. Renal involvement has been described in CLL but is uncommon. Granulomatous interstitial nephritis is a rare but characteristic hallmark of certain diseases such as sarcoidosis and tuberculosis. These epithelial reactions have also been reported with medications, infections, inflammation, Wegener's granulomatosis, and jejunoileal bypass. We present a 74-year-old woman with a stage 0 chronic lymphocytic leukemia who developed acute renal failure following the initiation of alendronate. The renal biopsy revealed an acute granulomatous interstitial nephritis. Infectious and inflammatory etiologies were ruled out. Hemodialysis was required despite discontinuation of all medications. Partial recovery of renal function occurred after 6 weeks of prednisone therapy and cyclophosphamide. This report describes a unique case of acute granulomatous interstitial nephritis and leukemic cell kidney infiltration by CLL.  相似文献   
64.
Objective To determine the efficacy of minocycline and rifampin-impregnated catheters compared to non-impregnated catheters in critically ill patients.Design Prospective, randomized, double-blind, controlled, multicenter trial.Setting Intensive care units of seven acute-care teaching hospitals in Spain.Patients Intensive care unit patients requiring triple-lumen central venous catheter for more than 3 days.Interventions At catheter insertion, 228 patients were randomized to minocycline and rifampin-impregnated catheters and 237 to non-impregnated catheters. Skin, catheter tip, subcutaneous segment, hub cultures, peripheral blood and infusate cultures were performed at catheter withdrawal. The rate of colonization, catheter-related bloodstream infection (CRBSI) and catheter-related clinical infectious complications (purulence at the insertion site or CRBSI) were assessed.Measurements and main results In the intention-to-treat analysis (primary analysis), the episodes per 1000 catheter days of clinical infectious complications decreased from 8.6 to 5.7 (RR =0.67, 95% CI 0.31–1.44), CRBSI from 5.9 to 3.1 (RR =0.53, 95% CI 0.2–1.44) and tip colonization from 24 to 10.4 (RR =0.43, 95% CI 0.26–0.73). Antimicrobial-impregnated catheters were associated with a significant decrease of coagulase-negative staphylococci colonization (RR =0.24, 95% CI 0.13–0.45) and a significant increase of Candida spp. colonization (RR =5.84, 95% CI 1.31–26.1).Conclusions The use of antimicrobial-impregnated catheters was associated with a significantly lower rate of coagulase-negative staphylococci colonization and a significant increase in Candida spp. colonization, although a decrease in CRBSI, increase in 30-day survival or reduced length of stay was not observed.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00134-004-2378-2This study was supported by a grant from Cook Europe.  相似文献   
65.
We analyzed the clinical and molecular data of 205 patients with the three different clinical forms of 21-hydroxylase deficiency, in whom the clinical and molecular diagnosis were already defined. The most frequent mutations were I2 splice in the salt wasting form, I172N in the simple virilizing and V281L in the nonclassical form, presenting similar frequencies as those observed in other populations. We found a lower frequency of 21-hydroxylase gene deletion, similar to that previously identified in Argentinean and Mexican populations. Five new mutations were described in our population: G424S, H28+C, Ins 1003 1004 A, R408C and IVS2-2A>G. The genotype was classified in three groups according to the impairment of enzymatic activity observed in vitro, Group A: 0-2%, Group B: 3-7% and Group C: >20%. Group A mutations correlated with the salt wasting form, the Group B with simple virilizing form and Group C with the non classical form. The severity of genotype showed a positive correlation with higher 17OH-progesterone and testosterone levels. The I2 splice mutation in homo or hemizygosis confers classical form phenotype with both salt wasting and simple virilizing forms, precluding the prediction of the clinical form through genotype in pre and neonatal diagnosis. The good genotype-phenotype correlation in patients with 21-hydroxylase deficiency shows the usefulness of genotype to predict the clinical form for genetic counseling, prenatal diagnosis and to confirm neonatal screening diagnosis, except in cases with I2 splice mutation.  相似文献   
66.
The intercalated islands are intra-amigdaloid clusters of D1 receptor rich GABAergic neurons, which control impulse traffic between the basolateral complex and the central nucleus of the amygdala. As dopaminergic transmission within the amygdala may play a role in anxiety, the effect of the D1 antagonist SCH23390 microinjected mainly close to the rostral intercalated islands in rats was studied, using the White and Black Box test. SCH23390 reduced anxiety by an increase in the latency of the first entry into the black compartment and by an increase in the total time spent in the white compartment of the White and Black Box test, while there was no significant modification of locomotion. It is suggested that blockade of D1 receptors in the rostral intercalated islands may reduce anxiety through a reduction of GABA-mediated dishinibition of the central amygdaloid nucleus.  相似文献   
67.
The present study was performed in order to obtain the thiopurine methyltransferase (TPMT) activity frequency distribution histogram in a Spanish population. A total of 3640 Spanish clinical laboratory samples were evaluated, which included 1249 patients with Crohn's disease, 589 with ulcerative colitis, 348 with multiple sclerosis (MS), 487 with several autoimmune diseases different from the above-mentioned diseases and 967 a donor group. We have measured the TPMT activity in red blood cells (RBCs) by a radiochemical method, using S-adenosyl-L-[methyl-3H]methionine as methyl donor. The different groups present in their entirety a normal distribution histogram and a wide range of TPMT activity from 0 to 41 U/ml RBCs. The differences found between the Spanish population TPMT activity frequency distribution histogram and the pattern previously described in a North American population were not due to azathioprine treatment or gender. The effect of autoimmune diseases on TPMT activity was evaluated: the enzymatic activity was similar in the donor group (19.9 +/- 6.3 U/ml RBCs) and in the patients with Crohn's disease (20.0 +/- 5.8 U/ml RBCs) and ulcerative colitis (19.7 +/- 6.1 U/ml RBCs); however, it decreased significantly (p<0.0001) in MS patients (17.1 +/- 6.1 U/ml RBCs) with respect to the donor group. In conclusion, our results show that the Spanish population TPMT distribution is closer to that of the Jewish population of Israel than to North American populations, and that in MS the enzymatic activity of TPMT decreases significantly. This observation may take into account the usage of azathioprine as therapeutic agent in Spanish MS patients.  相似文献   
68.
Our study demonstrated that the development of seizures during the electrically induced kindling of seizures is associated with significant changes in the concentration of kynurenic acid (KYNA) and its precursor, tryptophan (TRP). The primary finding of our study was an increase in KYNA levels and the KYNA/TRP ratio (a theoretical index of activity of the kynurenine pathway) in the amygdala and hippocampus of kindled animals. We also found decreases in the concentration of tryptophan in the hippocampus and prefrontal cortex. Changes in the concentration of KYNA and TRP in the amygdala were accompanied by a significant decrease in γ-Aminobutryic Acid (GABA) levels and an increase in the glutamate/GABA ratio. Moreover, we found a significant negative correlation between the local concentrations of KYNA and glutamate in the amygdala of kindled rats. However, there were no changes in the local concentrations of the following amino acids: glutamate, aspartate, glutamine, glycine, taurine and alanine. In conclusion, these new results suggest a modulatory influence of KYNA on the process of epileptogenesis, characterized by a negative relationship between the KYNA and glutamate systems in the amygdala.  相似文献   
69.
A vigorous controversy exists over whether tau tangles or amyloid-beta plaques are the primary cause of neurodegeneration in Alzheimer's disease (AD), and it is not well established whether genetic variation in tau is associated with AD. A recently identified novel protein, named Saitohin (STH), shares tissue expression pattern with tau, and preliminary evidence in a North American population indicates that a polymorphism at codon 7 (Q7R) of the STH gene is a predisposing factor for sporadic AD. A case-control study utilizing a clinically well-defined group of 315 sporadic AD patients and 307 control subjects was performed to test this association. The current study reveals that increased risk of AD associated with the STH RR genotype (OR 2.17, p = 0.04) is limited to late-onset (after the age of 72 years) AD cases.  相似文献   
70.
We studied a patient with ptosis, ophthalmoparesis, and exercise intolerance who showed in her muscle biopsy ragged-red fibers and combined defects of the complexes I and IV of the mitochondrial respiratory chain. Molecular analysis revealed a T3273C transition in the mitochondrial DNA tRNA(Leu(UUR)) gene. The mutation was heteroplasmic and very abundant in muscle from the proposita, less abundant in her other tissues studied, and still less abundant in blood from her maternal relatives. Single muscle fiber analysis showed significantly higher levels of mutant genomes in ragged-red fibers than in normal fibers. The T3273C mutation affects a strictly conserved base pair in the anticodon stem and was not found in controls, thus satisfying the accepted criteria for pathogenicity.  相似文献   
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