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11.
Pleuropulmonary blastoma (PPB) is a rare malignant mesenchymal pediatric tumor with a well-recognized association with congenital cystic adenomatoid malformation (CCAM). Recently, it has been described in a patient with CCAM, multiple jejunal polyps, and cystic nephroma. We describe a similar case of a unique presentation of PPB, arising in association with CCAM and with a history of intussception caused by multiple small bowel polyps.  相似文献   
12.
13.
We aimed to evaluate patient factors including nonadherence and viral infection and de novo donor‐specific antibody (dnDSA) characteristics [total immunoglobulin G (IgG), C1q, IgG3, and IgG4] as predictors of renal allograft failure in a multicenter cohort with dnDSA. We performed a retrospective observational study of 113 kidney transplant recipients with dnDSA and stored sera for analysis. Predictors of death‐censored allograft loss were assessed by Cox proportional modeling. Death‐censored allograft survival was 77.0% (87/113) during a median follow‐up of 2.2 (IQR 1.2–3.7) years after dnDSA detection. Predictors of allograft failure included medication nonadherence [HR 6.5 (95% CI 2.6–15.9)], prior viral infection requiring immunosuppression reduction [HR 5.3 (95% CI 2.1–13.5)], IgG3 positivity [HR 3.8 (95% CI 1.5, 9.3)], and time post‐transplant (years) until donor‐specific antibody (DSA) detection [HR 1.2 (95% CI 1.0, 1.3)]. In the 67 patients who were biopsied at dnDSA detection, chronic antibody‐mediated rejection [HR 11.4 (95% CI 2.3, 56.0)] and mixed rejection [HR 7.4 (95% CI 2.2, 24.8)] were associated with allograft failure. We conclude that patient factors, including a history of viral infection requiring immunosuppression reduction or medication nonadherence, combined with DSA and histologic parameters must be considered to understand the risk of allograft failure in patients with dnDSA.  相似文献   
14.
Our previous studies demonstrated fibrin glue (FG) prepared from cryoprecipitate (cryo) inhibits intra-abdominal adhesions in rats. A new FG, Hemaseel APR, is Food and Drug Administration (FDA) approved for hemostasis during cardiac surgery and splenic trauma. This study was undertaken to determine if Hemaseel FG prevents intra-abdominal adhesions, and to compare it to cryo FG. Forty-five rats underwent laparotomy. Bilateral peritoneal-muscular defects were created. Polypropylene mesh was sewn into each defect with a running silk suture. The bowel was abraded with gauze. The rats were then randomized to mesh covered with Hemaseel FG, cryo FG, or control. On postoperative day 7, the severity of adhesions were graded by percentage of mesh covered by adhesion (0-100%) and degree of adhesion (0-3). The mean percentage of mesh covered by adhesion was 9% for Hemaseel FG, 43% for cryo FG (p = .005), and 65% for the controls (p < .0001). The mean density adhesion score was 0.5 for Hemaseel FG, 1.2 for cryo FG (p = .04), and 2.1 for the controls (p < .0001). In the Hemaseel FG group, 77% of patches had no adhesions, compared with 37% in the cryo FG group (p = .004) and 13% in the controls (p < .0001). Thus, Hemaseel FG significantly decreases intra-abdominal adhesions, and is more effective than cryo FG.  相似文献   
15.
Respiratory center (RC) output has been shown to be increased in hypoxemic Chronic Obstructive patients at sea level. In order to asses the separate role of chronic hypoxia on the RC output we studied 30 normal subjects all of them native and residents of Mexico City (altitude: 2,240 m, PaO2: 65-70 torr.). The parameters studied were: occlussion pressure (P0.1), mean inspiratory flow (Vi), and the ratio inspiratory time to total duration of the respiratory cycle (Ti/Ttot). The inspiratory impedance of the respiratory system as well as the minute ventilation (VE) and lastly to ensure isocapnic conditions, the end-tidal CO2 (PECO2), were also measured. These parameters were determined: 1) While breathing room air (RA), 2) after 30 min of breathing an inspired oxygen fraction (FiO2) of 30% and again 3) after 30 min of breathing and FiO2 of 100%. Fifteen of the subjects were studied on supine and the other 15 in the seated position. In most of the subjects the baseline (RA) values of P0.1 were found to be higher than those reported for normals at sea level. In every case, independent of body position, the P0.1 decreased (less than 0.01) to normal sea level values after 30 min of breathing O2 30%. Likewise, Vi and mechanical impedance also decreased (p less than 0.01) and no changes in Ti/Ttot were noted at this FiO2. No further changes occurred after breathing 100%. The above results show that: 1) The RC output in normal people at altitude (i.e. without mechanical abnormalities but with chronic hypoxia) is increased as compared to sea level.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
16.
Hydralazine was administered short-term to 13 patients who had stable interstitial lung disease (ILD), pulmonary arterial hypertension (PAH); mean pulmonary arterial pressure ( [PAP]=26 +/- 9 mm Hg), and cor pulmonale (CP). All patients were studied at rest and during exercise. After intravenous hydralazine at rest, there were statistically significant increases in cardiac index (CI) (p less than 0.001), arterial oxygen saturation (SaO2) (p less than 0.01), and mixed venous saturation (S-vO2) (p less than 0.01). Pulmonary vascular resistance (Rp) (p less than 0.005) and systemic resistance (Rs) decreased (p less than 0.001), and PAP did not change. During exercise, PAP did not change; however, CI (p less than 0.01), PaO2 (p less than 0.001), and S-vO2 (p less than 0.01) increased further. The increase in Rp was significantly reduced (p less than 0.01). After continuation of oral hydralazine therapy in 12 patients for 7 days, PAP at rest was not statistically different from control; Rp and Rs remained decreased (p less than 0.001). The same results were found for CI, PaO2, S-vO2, and Rs during exercise. Although PAP did not change from control values, the drug significantly reduced the increase in Rp (p less than 0.005). Vasodilator therapy with hydralazine could be useful in patients with stable ILD who have inflammation with minimal to moderate fibrosis and PAH and might be used as an adjunct to conventional therapy for ILD and CP.  相似文献   
17.

Background

The tissue-protective effects of erythropoietin (EPO) have been extensively investigated, and EPO administration can raise the hemoglobin (Hb) concentration. Recently, we reported that carbamylated erythropoietin (CEPO) protected kidneys from ischemia-reperfusion injury as well as EPO.

Methods

To investigate the clinical applications of CEPO, we next evaluated the long-term therapeutic effect of CEPO using a tubulointerstitial model rat. We randomized remnant kidney model rats to receive saline, EPO, or CEPO for 8?weeks.

Results

CEPO- and EPO-treated rats had improved serum creatinine levels compared with saline-treated remnant kidney model rats, although the Hb level was significantly increased in EPO-treated rats. Two-photon microscopy revealed that EPO/CEPO significantly ameliorated tubular epithelial cell damage assessed by endocytosis. In addition, CEPO or EPO protected endothelial cells with a sustained blood flow rate. EPO or CEPO suppressed the number of TUNEL-positive apoptotic cells with weak ??SMA staining. Furthermore, PCR analysis demonstrated that TGF-?? and type I collagen expression was attenuated in EPO- or CEPO-treated rats, accompanied by a significant decrease in interstitial fibrosis.

Conclusion

We established a long-term therapeutic approach to protect tubulointerstitial injury with CEPO, and thus, the therapeutic value of this approach warrants further attention and preclinical studies.  相似文献   
18.
Estrogen blunts neuroendocrine and metabolic responses to hypoglycemia   总被引:3,自引:0,他引:3  
This study tested the hypothesis that estrogen is the mechanism responsible for the sexual dimorphism present in the neuroendocrine and metabolic responses to hypoglycemia. Postmenopausal women receiving (E2; n = 8) or not receiving (NO E2; n = 9) estrogen replacement were compared with age- and BMI-matched male subjects (n = 8) during a single-step 2-h hyperinsulinemic-hypoglycemic clamp. Plasma insulin (599 +/- 28 pmol/l) and glucose (2.9 +/- 0.03 mmol/l) levels were similar among all groups during the glucose clamp. In response to hypoglycemia, epinephrine (2.8 +/- 0.6 vs. 5.8 +/- 0.8 and 4.4 +/- 0.5 nmol/l), glucagon (57 +/- 8 vs. 77 +/- 8 and 126 +/- 18 ng/l), and endogenous glucose production (2 +/- 2 vs. 10 +/- 2 and 6 +/- 3 micro mol x kg(-1) x min(-1)) were significantly lower in E2 vs. both NO E2 and male subjects (P < 0.05). These reduced counterregulatory responses resulted in significantly greater glucose infusion rates (16 +/- 2 vs. 6 +/- 2 and 6 +/- 3 micro mol x kg(-1) x min(-1); P < 0.01) in E2 vs. both NO E2 and male subjects. Pancreatic polypeptide was significantly lower (P < 0.05) in both the E2 and NO E2 groups compared with the male subjects (136 +/- 20 and 136 +/- 23 vs. 194 +/- 16 pmol/l). Last, glycerol (36 +/- 3 vs. 47 +/- 5 micro mol/l; P < 0.05), lactate (1.4 +/- 0.1 vs. 1.8 +/- 0.2 mmol/l; P < 0.05), and muscle sympathetic nerve activity (19 +/- 4 to 27 +/- 4 vs. 27 +/- 5 to 42 +/- 6 bursts/min; P < 0.05) responses to hypoglycemia were all significantly lower in E2 vs. NO E2 subjects. We conclude that estrogen appears to play a major role in the sexual dimorphism present in counterregulatory responses to hypoglycemia in healthy humans.  相似文献   
19.
Direct‐acting antiviral agents (DAA) combining daclatasvir (DCV) have reported good outcomes in the recurrence of hepatitis C virus (HCV) infection after liver transplant (LT). However, its effect on the severe recurrence and the risk of death remains controversial. We evaluated the efficacy, predictors of survival, and safety of DAC‐based regimens in a large real‐world cohort. A total of 331 patients received DCV‐based therapy. Duration of therapy and ribavirin use were at the investigator's discretion. The primary end point was sustained virological response (SVR) at week 12. A multivariate analysis of predictive factors of mortality was performed. Intention‐to‐treat (ITT) and per‐protocol SVR were 93.05% and 96.9%. ITT‐SVR was lower in cirrhosis (n = 163) (96.4% vs. 89.6% P = 0.017); the SVR in genotype 3 (n = 91) was similar, even in advanced fibrosis (96.7% vs. 88%, P = 0.2). Ten patients (3%) experienced virological failure. Therapy was stopped in 18 patients (5.44%), and ten died during treatment. A total of 22 patients (6.6%) died. Albumin (HR = 0.376; 95% CI 0.155–0.910) and baseline MELD (HR = 1.137; 95% CI: 1.061–1.218) were predictors of death. DCV‐based DAA treatment is efficacious and safe in patients with HCV infection after LT. Baseline MELD score and serum albumin are predictors of survival irrespective of viral response.  相似文献   
20.
OBJECTIVE—Glucagon-like peptide-1 (GLP-1) promotes glucose homeostasis through regulation of islet hormone secretion, as well as hepatic and gastric function. Because GLP-1 is also synthesized in the brain, where it regulates food intake, we hypothesized that the central GLP-1 system regulates glucose tolerance as well.RESEARCH DESIGN AND METHODS—We used glucose tolerance tests and hyperinsulinemic-euglycemic clamps to assess the role of the central GLP-1 system on glucose tolerance, insulin secretion, and hepatic and peripheral insulin sensitivity. Finally, in situ hybridization was used to examine colocalization of GLP-1 receptors with neuropeptide tyrosine and pro-opiomelanocortin neurons.RESULTS—We found that central, but not peripheral, administration of low doses of a GLP-1 receptor antagonist caused relative hyperglycemia during a glucose tolerance test, suggesting that activation of central GLP-1 receptors regulates key processes involved in the maintenance of glucose homeostasis. Central administration of GLP-1 augmented glucose-stimulated insulin secretion, and direct administration of GLP-1 into the arcuate, but not the paraventricular, nucleus of the hypothalamus reduced hepatic glucose production. Consistent with a role for GLP-1 receptors in the arcuate, GLP-1 receptor mRNA was found to be expressed in 68.1% of arcuate neurons that expressed pro-opiomelanocortin mRNA but was not significantly coexpressed with neuropeptide tyrosine.CONCLUSIONS—These data suggest that the arcuate GLP-1 receptors are a key component of the GLP-1 system for improving glucose homeostasis by regulating both insulin secretion and glucose production.The importance of gastrointestinal hormones signaling gut absorption of carbohydrates and downstream processes involved in glucose disposal has received increasing attention. Prominent among these is glucagon-like peptide-1 (GLP-1), which is produced by L-cells of the ileum and is secreted during meal ingestion. GLP-1 augments nutrient-induced insulin release (1,2), inhibits glucagon release (3), slows gastric emptying (4), and has islet-independent effects to reduce hepatic glucose production (58). Studies in animals and humans have demonstrated that GLP-1 signaling is necessary for normal glucose tolerance (9). Moreover, two newly approved therapies for type 2 diabetic patients act through GLP-1 signaling to improve glucose homeostasis.Most of the evidence demonstrating a role for GLP-1 in glucose homeostasis has focused on actions within the pancreatic islet. However, GLP-1 is also synthesized in a discrete population of neurons in the hindbrain (1012), and GLP-1 receptors are highly expressed in various regions of the hypothalamus (13) including the arcuate nucleus (ARC) and the paraventricular nucleus (PVN) (14), two areas where immunoreactive GLP-1 fibers terminate (11). Central nervous system (CNS) GLP-1 receptors have been linked to the control of food intake, endocrine and behavioral responses to stress, and visceral illness (1517). Although there is evidence that circulating GLP-1 agonists can activate CNS neurons (18) and that GLP-1 may cross the blood-brain barrier (19), central and peripheral GLP-1 signaling systems are generally held to be separate.Compelling recent evidence links a number of CNS systems to the regulation of peripheral glucose levels. While hypothalamic areas such as the PVN and the dorsal medial and the ventromedial hypothalamus may play a role in glucose homeostasis during stress (2022), there is strong evidence that the ARC plays a key role in maintaining normal glucose levels in response to anorectic peptides or nutrients by regulation of glucose production (2326). Given this emerging evidence for CNS involvement in the regulation of peripheral metabolism and the broad role that peripheral GLP-1 signaling plays in regulating glucose homeostasis, we hypothesized that CNS GLP-1 receptors would have multiple coordinated effects to improve glucose tolerance. Specifically, we focused on the ARC because GLP-1 receptors are found in this region, and previous studies have shown that neurons in this area regulate glucose production. Thus, a second hypothesis was that ARC GLP-1 receptors regulate glucose output. Finally, using dual in situ hybridization histochemistry, we evaluated ARC GLP-1 receptor expression on orexigenic neuropeptide tyrosine (NPY) and anorexigenic proopiomelanocortin (POMC) neurons.  相似文献   
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