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21.

Background and objectives

Plasma copeptin, a marker of arginine vasopressin, is elevated in patients with autosomal dominant polycystic kidney disease and predicts disease progression. It is unknown whether elevated copeptin levels result from decreased kidney clearance or as compensation for impaired concentrating capacity. Data from patients with autosomal dominant polycystic kidney disease and healthy kidney donors before and after donation were used, because after donation, overall GFR decreases with a functionally normal kidney.

Design, setting, participants, & measurements

Data were obtained between October of 2008 and January of 2012 from healthy kidney donors who visited the institution for routine measurements predonation and postdonation and patients with autosomal dominant polycystic kidney disease who visited the institution for kidney function measurement. Plasma copeptin levels were measured using a sandwich immunoassay, GFR was measured as 125I-iothalamate clearance, and urine concentrating capacity was measured as urine-to-plasma ratio of urea. In patients with autosomal dominant polycystic kidney disease, total kidney volume was measured with magnetic resonance imaging.

Results

Patients with autosomal dominant polycystic kidney disease (n=122, age=40 years, men=56%) had significantly higher copeptin levels (median=6.8 pmol/L; interquartile range=3.4–15.7 pmol/L) compared with donors (n=134, age=52 years, men=49%) both predonation and postdonation (median=3.8 pmol/L; interquartile range=2.8–6.3 pmol/L; P<0.001; median=4.4 pmol/L; interquartile range=3.6–6.1 pmol/L; P<0.001). In donors, copeptin levels did not change after donation, despite a significant fall in GFR (from 105±17 to 66±10; P<0.001). Copeptin and GFR were significantly associated in patients with autosomal dominant polycystic kidney disease (β=−0.45, P<0.001) but not in donors. In patients with autosomal dominant polycystic kidney disease, GFR and total kidney volume were both associated significantly with urine-to-plasma ratio of urea (β=0.84, P<0.001; β=−0.51, P<0.001, respectively).

Conclusions

On the basis of the finding in donors that kidney clearance is not a main determinant of plasma copeptin levels, it was hypothesized that, in patients with autosomal dominant polycystic kidney disease, kidney damage and associated impaired urine concentration capacity determine copeptin levels.  相似文献   
22.
AIM:To investigate if the presence of relevant genetic polymorphisms has effect on the effectual clearance of bacteria by monocytes and granulocytes in patients with Crohn’s disease(CD).METHODS:In this study,we assessed the differential responses in phagocytosis by measuring the phagocytic activity and the percentage of active phagocytic monocytes and granulocytes in inflammatory bowel disease patients as well as healthy controls.As both autophagy related like 1(ATG16L1)and immunityrelated guanosine triphosphatase gene are autophagy genes associated with CD and more recently nucleo-tide-binding ligomerization domain-containing protein2(NOD2)has been identified as a potent inducer of autophagy we genotyped the patients for these variants and correlated this to the phagocytic reaction.The genotyping was done with restriction fragment length polymorphisms analysis and the phagocytosis was determined with the pHrodo?Escherichia coli Bioparticles Phagocytosis kit for flowcytometry.RESULTS:In this study,we demonstrate that analysis of the monocyte and granulocyte populations of patients with CD and ulcerative colitis showed a comparable phagocytic activity(ratio of mean fluorescence intensity)between the patient groups and the healthy controls.CD patients show a significantly higher phagocytic capacity(ratio mean percentage of phagocytic cells)compared to healthy controls(51.91%±2.85%vs 37.67%±7.06%,P=0.05).The extend of disease was not of influence.However,variants of ATG16L1(WT:2.03±0.19 vs homozygoot variant:4.38±0.37,P<0.009)as well as NOD2(C-ins)(heterozygous variant:42.08±2.94 vs homozygous variant:75.58±4.34(P=0.05)are associated with the phagocytic activity in patients with CD.CONCLUSION:Monocytes of CD patients show enhanced phagocytosis associated with the presence of ATG16L1 and NOD2 variants.This could be part of the pathophysiological mechanism resulting in the disease.  相似文献   
23.
Helminths and their products can suppress the host immune response which may benefit parasite survival. Trichinella spiralis can establish chronic infections in a wide range of mammalian hosts including humans and mice. Here, we aim at studying the effect of T. spiralis muscle larvae excretory/secretory products (TspES) on the functionality of DC and T cell activation. We found that TspES suppress in vitro DC maturation induced by both S- and R-form lipopolysaccharide(LPS) from enterobacteria. Using different toll-like receptor (TLR) agonists, we show that the suppressive effect of TspES on DC maturation is restricted to TLR4. These helminth products also interfere with the expression of several genes related to the TLR-mediated signal transduction pathways. To investigate the effect of TspES on T cell activation, we used splenocytes derived from OVA-TCR transgenic D011.10 that were incubated with OVA and TspES-pulsed DC. Results indicate that the presence of TspES resulted in the expansion of CD4(+) CD25(+) Foxp3+ T cells. These regulatory T (Treg) cells were shown to have suppressive activity and to produce TGF-β. Together these results suggest that T. spiralis secretion products can suppress DC maturation and induce the expansion of functional Treg cells in vitro.  相似文献   
24.
25.

Purpose

In peptide receptor radionuclide therapy (PRRT), the bone marrow (BM) is one of the dose-limiting organs. The accepted dose limit for BM is 2 Gy, adopted from 131I treatment. We investigated the incidence and duration of haematological toxicity and its risk factors in patients treated with PRRT with 177Lu-DOTA0-Tyr3-octreotate (177Lu-DOTATATE). Also, absorbed BM dose estimates were evaluated and compared with the accepted 2 Gy dose limit.

Methods

The incidence and duration of grade 3 or 4 haematological toxicity (according to CTCAE v3.0) and risk factors were analysed. Mean BM dose per unit (gigabecquerels) of administered radioactivity was calculated and the correlations between doses to the BM and haematological risk factors were determined.

Results

Haematological toxicity (grade 3/4) occurred in 34 (11 %) of 320 patients. In 15 of the 34 patients, this lasted more than 6 months or blood transfusions were required. Risk factors significantly associated with haematological toxicity were: poor renal function, white blood cell (WBC) count <4.0?×?109/l, age over 70 years, extensive tumour mass and high tumour uptake on the OctreoScan. Previous chemotherapy was not associated. The mean BM dose per administered activity in 23 evaluable patients was 67?±?7 mGy/GBq, resulting in a mean BM dose of 2 Gy in patients who received four cycles of 7.4 GBq 177Lu-DOTATATE. Significant correlations between (cumulative) BM dose and platelet and WBC counts were found in a selected group of patients.

Conclusion

The incidence of subacute haematological toxicity after PRRT with 177Lu-DOTATATE is acceptable (11 %). Patients with impaired renal function, low WBC count, extensive tumour mass, high tumour uptake on the OctreoScan and/or advanced age are more likely to develop grade 3/4 haematological toxicity. The BM dose limit of 2 Gy, adopted from 131I, seems not to be valid for PRRT with 177Lu-DOTATATE.
  相似文献   
26.
BACKGROUND: Little is known on the actual diagnostic and therapeutic management of recurrent miscarriage and the impact of introducing guidelines on this topic. The objective of this study was to evaluate any changes in the management of recurrent miscarriage among Dutch gynaecologists after the introduction of the Dutch guideline 'Recurrent Miscarriage' in 1999. METHODS: Questionnaires were sent to all practices for obstetrics and gynaecology in the Netherlands. Data concerned definition, diagnosis and treatment of recurrent miscarriage. Results were compared with a similar study conducted before the introduction of the guideline and with the recommendations in the guideline. RESULTS: The response rate was 83%. Regarding gestational age, only 3% of the respondents used the definition as advised in the guideline. After the introduction of the guideline, thrombophilia factors were tested more frequently, anticoagulants were prescribed more frequently and more respondents reported to correct uterine malformations. Therapies not described in the guideline, e.g. donor insemination and oocyte donation, were still applied. CONCLUSIONS: The adherence to the Dutch guideline 'Recurrent Miscarriage' was rather poor, presumably due to guideline-related as well as physician-related barriers. Too many diagnostic tests and ineffective therapeutic interventions were performed. This study demonstrates the importance of appropriate implementation and revision.  相似文献   
27.
Biomarkers that predict treatment effects may be used to guide treatment decisions, thus improving patient outcomes. A meta‐analysis of individual participant data (IPD) is potentially more powerful than a single‐study data analysis in evaluating markers for treatment selection. Our study was motivated by the IPD that were collected from 2 randomized controlled trials of hypertension and preeclampsia among pregnant women to evaluate the effect of labor induction over expectant management of the pregnancy in preventing progression to severe maternal disease. The existing literature on statistical methods for biomarker evaluation in IPD meta‐analysis have evaluated a marker's performance in terms of its ability to predict risk of disease outcome, which do not directly apply to the treatment selection problem. In this study, we propose a statistical framework for evaluating a marker for treatment selection given IPD from a small number of individual clinical trials. We derive marker‐based treatment rules by minimizing the average expected outcome across studies. The application of the proposed methods to the IPD from 2 studies in women with hypertension in pregnancy is presented.  相似文献   
28.

Background

Cytoreductive surgery (CRS) with heated intraperitoneal chemotherapy (HIPEC) has gained acceptance in the treatment of peritoneal carcinomatosis with reported morbidity and mortality rates of 27–56 and 0–11 %, respectively. The safety and oncologic outcome of genitourinary repair at the time of CRS and HIPEC remains unclear.

Methods

We identified 170 patients who underwent CRS-HIPEC at our institution between July 2007 and August 2011 with a minimum follow-up of 6 months. Thirty-four (20 %) underwent concomitant urologic reconstruction at the time of CRS-HIPEC and were matched by disease burden (intraoperative peritoneal cancer index [PCI]) and extent of surgery (ΔPCI) with a cohort of 38 (22.3 %) subjects without genitourinary involvement. The primary end points considered for this analysis included the development of major surgical (Clavien–Dindo Class III–V) complications and overall survival.

Results

Median follow-up was 9.4 months. The most commonly performed urologic interventions included partial cystectomy with primary repair in 23 (65.7 %) and segmental ureteral resection and repair in 11 (31.4 %). Patients with genitourinary reconstruction had more total organ involvement (6.5 vs. 4.3, p < 0.001) and more commonly underwent enteric anastomoses (82.4 vs. 57.9 %, p = 0.025). No significant differences were observed with regard to major morbidity, need for transfusion, operative time, intensive care unit admission, or length of stay. Among patients with appendiceal or colonic tumors (n = 46), overall survival was similar between genitourinary reconstruction and matched cohorts: 22.5 versus 15.1 months, respectively (p = 0.66).

Conclusions

Genitourinary reconstruction at the time of CRS-HIPEC occurs more commonly in patients with extensive disease burden undergoing radical debulking, yet does not adversely influence surgical morbidity or survival.  相似文献   
29.

Background  

Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.  相似文献   
30.
The purpose of this report was to evaluate scintigraphy analysis of Southern blot hybridization as a method to quantify the breakpoint cluster region (BCR) rearrangement of Philadelphia chromosome (Ph)+ chronic myelogenous leukemia (CML). Cytogenetic and molecular studies performed simultaneously on 474 bone marrow and/or blood samples from 300 patients treated with alpha-interferon-based therapy were compared. Molecular results were expressed as the percentage of rearranged BCR bands versus the total scintigraphic signal. The percentage of Ph+ metaphases was calculated on 25 metaphases. The results of molecular studies obtained on both peripheral blood and bone marrow samples were identical. The rank correlation between the BCR quantification and the percentage of Ph positivity in 465 samples was excellent (r = .78). However, of 99 samples with a normal karyotype, 24% had a BCR rearrangement. Of 86 samples with no BCR rearrangement, 13% showed a Ph chromosome. Of 49 samples with partial cytogenetic remission (Ph+ metaphases, 1% to 34%), 23% had no BCR rearrangement. In samples with a minor or no cytogenetic response (Ph+ metaphases, > 34%), BCR analysis overestimated the degree of response in 73 of 326 samples (22%). Nevertheless, survival analysis by BCR quantification level showed statistically better outcome for patients in complete or partial molecular response (P < .01). Molecular quantification of BCR was useful in monitoring the course of Ph+ CML. This method, which can be used on peripheral blood, detected residual disease not shown by cytogenetic analysis and was prognostically relevant as a measure of disease suppression.  相似文献   
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