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31.
Background: The impact of marathon running on kidney function has not been previously described. Methods: From 425 marathon runners, 13 women and 12 men were randomly selected and cardiovascular magnetic resonance imaging (MRI) and blood/urine biomarkers were performed 4 weeks before (baseline), immediately after (peak), and 24 h after the race (recovery). Results: Participants were 38.7 ± 9.0 years old and completed the marathon in 256.2 ± 43.5 min. A total of 10/25 (40.0%) met the Acute Kidney Injury Network definition of acute kidney injury (AKI) based on a rise in serum creatinine. There were parallel and similar mean rises in serum creatinine and cystatin C from baseline, to peak, and return to normal in recovery. Urine neutrophil gelatinase‐associated lipocalin rose from 8.2 ± 4.0 to 47.0 ± 28.6 and returned to 10.6 ± 7.2 ng/mL, P < 0.0001. Likewise, the mean urinary kidney injury molecule‐1 levels were 2.6 ± 1.6, 3.5 ± 1.6 and 2.7 ± 1.6 ng/mL (P = 0.001). The mean and minimum pre‐ and post‐IVC (inferior vena cava) diameters by MRI were 24.9, 18.8 and 25.3, 17.5 mm, respectively, suggesting that runners were not volume depleted at the first post‐race measurement. Conclusion: Approximately 40% of marathon runners experience a transient rise in serum creatinine that meets criteria of AKI with a parallel elevation of cystatin C, and supportive elevations of neutrophil gelatinase‐associated lipocalin and kidney injury molecule‐1 in the urine. All biomarker elevations resolved by 24 h. These data suggest that AKI with a transient and minor change in renal filtration function occurs with the stress of marathon running. The impact of repetitive episodes of AKI with long‐distance running is unknown.  相似文献   
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BACKGROUND: Bariatric surgery achieves long-term weight loss in obese adults with improvement of diabetes and hypertension. Little is known about the effect of this weight loss on renal parameters. METHODS: We performed a retrospective study of 94 obese adults who had Roux-en-Y gastric bypass surgery with a mean 12-month follow-up. Baseline (preoperative) mean age was 49 years, 76% were female, 37 had blood pressure (BP) >or= 140/90 mmHg and 32 had Type 2 diabetes. 73 patients had normoalbuminuria (urine albumin creatinine ratio (ACR) <30 mg/g) while 21 had microalbuminuria (ACR 30<300 mg/g). RESULTS: At follow-up (postoperative), we observed a decrease in mean body weight (133.6 to 97.9 kg, p<0.0001), mean hemoglobin A1c (6.3 to 5.6%, p<0.0001) and mean systolic blood pressure (132.7 to 114.0 mmHg, p<0.0001). There was a significant reduction in ACR (median with interquartile range) from 9.5 (5-28) to 5.5 (3-10) mg/g, p < 0.0001. Fewer patients had microalbuminuria (22.2 to 6.2%, p=0.004) after surgery. Subgroup analysis revealed that significant decrease in ACR was present in the 32 patients with diabetes (16.5 (5-67) to 6.0 (4-11) mg/g, p=0.001) and in the 37 patients with metabolic syndrome (8.0 (5-16) to 6.0 (3-13) mg/g, p=0.012), while 25 patients with obesity alone had a lower ACR (6.5 (4-13) to 4.5 (3-8) mg/g, p=0.270). Multiple linear regression analysis showed change in hemoglobin A1c (p=0.011) and baseline level of ACR (p<0.0001) to be significantly associated with change in ACR. CONCLUSION: We conclude that obese adults have a reduction in albuminuria after surgical weight loss, most importantly in patients with diabetes or metabolic syndrome.  相似文献   
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Disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. However, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. Here we show decreased cortical bone turnover during hibernation with balanced formation and resorption in grizzly bear femurs. Hibernating grizzly bear femurs were less porous and more mineralized, and did not demonstrate any changes in cortical bone geometry or whole bone mechanical properties compared to active grizzly bear femurs. The activation frequency of intracortical remodeling was 75% lower during hibernation than during periods of physical activity, but the normalized mineral apposition rate was unchanged. These data indicate that bone turnover decreases during hibernation, but osteons continue to refill at normal rates. There were no changes in regional variation of porosity, geometry, or remodeling indices in femurs from hibernating bears, indicating that hibernation did not preferentially affect one region of the cortex. Thus, grizzly bears prevent bone loss during disuse by decreasing bone turnover and maintaining balanced formation and resorption, which preserves bone structure and strength. These results support the idea that bears possess a biological mechanism to prevent disuse osteoporosis.  相似文献   
34.
Afibrinogenemia is a rare hereditary coagulation disorder characterized by a propensity toward bleeding. A 21-year-old Hispanic woman with afibrinogenemia developed ascites, a distended abdomen, an enlarged liver, scleral icterus, and umbilical vein and abdominal wall vein distension. Computed tomography (CT) scan showed occlusion of the hepatic veins and the infrahepatic vena cava consistent with Budd-Chiari syndrome. These developments led to her evaluation for, and placement on, the liver transplantation waiting list. The patient's unmeasurable international normalized ratio (INR) artifactually increased her Model for End-Stage Liver Disease (MELD) score to 40. Immediately before transplant surgery, an initial thrombelastogram (TEG) showed a flat line, indicating a complete lack of fibrin clot formation. Preoperatively, 20 units of cryoprecipitate were infused. The first intraoperative TEG demonstrated a tracing consistent with normal clot formation. Coagulation studies normalized with the newly functioning liver. The liver transplantation appears to have corrected the fibrinogen deficiency, presumably limiting the chance of recurrent Budd-Chiari syndrome. This case report discusses the essential role of fibrinogen in the coagulation cascade, as visualized by thrombelastography, and exposes the interplay between plasma fibrinogen and thrombin levels, which determine coagulation or fibrinolysis.  相似文献   
35.
The incidence of breast cancer diagnosed during pregnancy is increasing. We sought to characterize patient, treatment, pregnancy and lactation factors among young women with newly diagnosed breast cancer during pregnancy in a prospective cohort study. We identified all women who were pregnant when diagnosed with invasive breast cancer among those enrolled in the Young Women's Breast Cancer Study (NCT01468246), and collected details on pregnancy, birth and lactation from surveys, and treatment information medical record review. Of 1302 enrolled participants, 976 women with invasive breast cancer completed full baseline surveys, among whom 39 (4.0%) patients reported being pregnant at diagnosis. Median age at diagnosis was 34 years (range: 25‐40), with stage distribution: I, 28%; II, 44%; III, 23%; and IV, 5%. 74% of patients (29/39) had grade 3 tumors, 59% (23/39) ER‐positive, and 31% (12/39) HER2‐positive disease. 23 (59%) had surgery during pregnancy, 4 (17%) during the first trimester. Among the women who had surgery during pregnancy, 61% (14/23) underwent lumpectomy, 35% (8/23) unilateral, and 4% (1/23) bilateral mastectomy. All patients who had chemotherapy (51%, 20/39) received it in second and third trimesters, and had ACx4. There were 31 live births, 2 spontaneous, and 5 therapeutic abortions. Among live births, 16 (41%) were before 37 weeks of gestation. Three women reported breastfeeding. Within 6 months after delivery, comprehensive staging in 13 patients showed upstaging in four patients. In a contemporary cohort of young women with breast cancer, pregnancy at diagnosis is relatively uncommon. Treatment during pregnancy can generally be consistent with standard surgical and chemotherapy approaches, with attention to timing of therapies. Longer‐term outcomes including effects of some timing issues including delayed use of anti‐HER2 therapy on patient outcomes warrant further research.  相似文献   
36.
Annals of Surgical Oncology - The role of sentinel lymph node biopsy (SLNB) when ductal carcinoma in situ with microinvasion (DCISM) is identified on core biopsy is unclear. Our aim was to assess...  相似文献   
37.
This article presents an overview of factors associated with thoracic transplantation outcomes over the past decade and provides valuable information regarding the heart, lung, and heart-lung waiting lists and thoracic organ transplant recipients. Waiting list and post-transplant information is used to assess the importance of patient demographics, risk factors, and primary cardiopulmonary disease on outcomes.
The time that the typical listed patient has been waiting for a heart, lung, or heart-lung transplant has markedly increased over the past decade, while the number of transplants performed has declined slightly and survival after transplant has plateaued. Waiting list mortality, however, appears to be declining for each organ and for most diseases and high-severity subgroups, perhaps in response to recent changes in organ allocation algorithms. Based on perceived inequity in organ access and in response to a mandate from Health Resources and Services Administration, the lung transplant community is developing a lung allocation system designed to minimize deaths on the waiting list while maximizing the benefit of transplant by incorporating post-transplant survival and quality of life into the algorithm. Areas where improved data collection could inform evolving organ allocation and candidate selection policies are emphasized.  相似文献   
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The granulocyte immunofluorescence test (GIFT) is valuable for detecting allogeneic and autologous granulocyte antibodies. However, the original tube technique (macro GIFT) requires 50-100 microliters of serum and 10(6) granulocytes with time-consuming washing steps which cause cell loss. We report a modification (micro GIFT) using microtiter trays which requires only 20 microliters of serum and 2 X 10(5) granulocytes. The modified method conserves reagents, reduces the time required for washing by 67%, decreases cell loss in washing by 74%, reduces the volume of conjugate required by 67%, and compares favorably with the macro GIFT in accuracy, specificity, and sensitivity.  相似文献   
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