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21.

Objective

Currently, there is no effective paradigm to identify patients who are at risk for renal dysfunction following cardiac surgery. The specific mechanisms of renal injury during surgery are incompletely understood. The aim of the study was to evaluate whether postoperative renal dysfunction can be predicted from intraoperative glomerular filtration rate (GFR).

Design

This is a prospective study.

Setting

The study was conducted in a tertiary care multi-specialty hospital.

Participants and interventions

GFR was measured in 24 patients (mean age 56.6 ± 11.09 years, 20 male) undergoing elective off-pump coronary artery bypass grafting during preoperative period, intraoperative period, 24 h after surgery (ICU GFR), and on the fifth postoperative day (final GFR ).

Measurements and main results

Patients were divided into two groups depending upon changes in intraoperative GFR. Group 1 (n = 10): who had a rise in intraoperative GFR in comparison with preoperative baseline measurement. All these 10 (41.7 %) patients with a rise in intraoperative GFR had an uneventful hospital course and achieved an improvement in final GFR. Group 2 (n = 14): 14 (58.3 %) patients had a fall in intraoperative GFR (mean 36.4 %) in comparison with preoperative baseline value. Of these 14 patients, 1 patient required dialysis support and 3 patients required ionotropic support. Among these 14 patients in group two, 7 had deterioration in final GFR (mean 28.7 %), when compared to preoperative baseline value.

Conclusion

Postoperative renal dysfunction can be predicted from intraoperative GFR. Patients who have a rise in intraoperative GFR do not develop postoperative renal dysfunction, and only patients with intraoperative fall in GFR are at risk of postoperative renal dysfunction.
  相似文献   
22.
We studied the safety and feasibility of laparoscopic radical cystectomy (LRC) in patients with loco-regionally advanced bladder cancer and report the short-term oncological outcome. This study comprised a total of 13 patients (10 males, 3 females), who presented with myriad of symptoms and on imaging they were found to have radiologically evident advanced disease (6 pelvic lymphadenopathies, 10 extravesical tumor extensions, three prostate/seminal vesical invasions). In view of recalcitrant symptoms (hematuria, frequency and irritative voiding) all patients underwent LRC and bilateral modified pelvic lymphadenectomy with ileal conduit urinary diversion. Mean age of the patients was 56.3 years. Mean operative time was 310 min with an average blood loss of 556 ml. No major intra-operative complications were noted. One patient died in the post-operative period due to sepsis. Histopathology report revealed pT3b N0 in two patients; pT3b N1 in four; pT3b N2 in three; pT4a N0 in one, and pT4aN1 in three patients. Adjuvant chemotherapy was administered in nine patients. At mean follow up of 18 months (range 6–28), seven patients are alive and cancer-free, while two patients are alive with metastases. LRC provides an alternative approach for treatment of patients with loco-regionally advanced bladder cancer, who suffer from recurrent hematuria and severe irritative voiding symptoms, in whom open surgery was the standard approach hitherto. However, it should be considered experimental and should be attempted only by surgeons who have significant experience of laparoscopic pelvic surgery and advanced skills, and after discussing the potential risks and benefits with the patient.  相似文献   
23.
Leflunomide (LEF) is a synthetic isoxazole derivative with anti-inflammatory and antiviral properties, which has been reported to prevent acute rejection and delay progression of chronic allograft nephropathy (CAN) in animal models. We performed a pilot, crossover trial in 22 renal transplant recipients who were converted from azathioprine (AZA) or mycophenolate mofetil (MMF) to LEF in an effort to slow progression of renal dysfunction [deteriorating renal function (n = 5), cyclosporine (CyA) nephrotoxicity (n = 4) or biopsy-proven CAN (n = 13)]. Baseline maintenance immunosuppression consisted of CyA, AZA or MMF and prednisone. Six-month postconversion patient and graft survival was 100% and 91%, respectively. Mean serum creatinine 6months preconversion was 2.2 +/- 0.6mg/dL, at initiation was 3.0 +/- 1.1 mg/dL, and 6 months postconversion was 2.8 +/- 1.3 mg/dL. The rate of change in serum creatinine was 35 +/- 39%/6 months preconversion and -5 +/- 21%/6 months postconversion to LEF (p = 0.003). Two patients discontinued LEF for diarrhea and myalgia. No readmissions, increase in liver function tests, infections or acute rejection episodes occurred. Mean CyA levels did not change, 146 +/- 72 ng/ mL pre-LEF vs. 132 +/- 51 ng/mL post-LEF, p = NS. Conversion to LEF reversed progression of chronic renal allograft dysfunction with minimal toxicity.  相似文献   
24.
25.
A study of autologous melanocyte transfer in treatment of stable vitiligo   总被引:1,自引:0,他引:1  
BACKGROUND: Replenishing melanocytes selectively in vitiliginous macules by autologous melanocytes is a promising treatment. With expertise in culturing melanocytes, it has now become possible to treat larger recipient areas with smaller skin samples. AIM: To study the extent of repigmentation after autologous melanocyte transplantation in patients with stable vitiligo. METHODS: The melanocytes were harvested as an autologous melanocyte rich cell suspension from a donor split thickness graft. Melanocyte culture was performed in selected cases where the melanocyte cell count was insufficient to meet the requirement of the recipient area. These cells were then transplanted to the recipient area that had been superficially dermabraded. RESULTS: An excellent response was seen in 52.17% cases with the autologous melanocyte rich cell suspension (AMRCS) technique and in 50% with the melanocyte culture (MC) technique. CONCLUSION: Autologous melanocyte transplantation can be an effective form of surgical treatment in stable but recalcitrant lesions of vitiligo.  相似文献   
26.
27.
Contact precautions are recommended in hospitals to prevent the transmission of vancomycin-resistant enterococci (VRE); however, there is no clear policy for how long patients should be under contact precautions due to a lack of information on the duration of carriage of these organisms. We conducted a retrospective cohort study to understand the duration of carriage of VRE (by screening of a single stool culture) and associated factors among patients who had been identified with VRE infection and/or colonization since the year 2000 at our health facilities. Of the 345 eligible participants, 136 did not respond, 90 declined to participate, and 16 did not send in the required specimens. Of the 103 remaining participants, 13 were found to have current VRE fecal carriage. The proportion of colonized patients fell from 40% (2/5) in the first year to 23.3% (7/30) in year 4. None of the 40 patients who had VRE detected >4 years prior were found to be colonized at the time of the study. The longest duration of detected VRE positivity was 46.5 months. Univariate analysis revealed that recent exposure to any antibiotics (P = 0.016), multiple antibiotics (P = 0.001), amoxicillin-clavulanic acid (P = 0.021), piperacillin-tazobactam (P = 0.007), glycopeptides (P < 0.001), meropenem (P = 0.007), aminoglycosides (P = 0.021), or fluoroquinolones (P = 0.021), being the index case in a clinical specimen (P = 0.016), and recent hospitalization (P < 0.001) were significantly associated with continued carriage on follow-up. In the surviving outpatients, a significant proportion appeared to clear VRE carriage. Our results suggest that in the absence of recent risk factors, such as hospitalization or antibiotic use, patients with a remote history of colonization (>4 years) may no longer require contact isolation precautions.  相似文献   
28.
Preeclampsia is a major pregnancy complication with potential short- and long-term consequences for both mother and fetus. Understanding its pathogenesis and causative biomarkers is likely to yield insights for prediction and treatment. Herein, we provide evidence that transthyretin, a transporter of thyroxine and retinol, is aggregated in preeclampsia and is present at reduced levels in sera of preeclamptic women, as detected by proteomic screen. We demonstrate that transthyretin aggregates form deposits in preeclampsia placental tissue and cause apoptosis. By using in vitro approaches and a humanized mouse model, we provide evidence for a causal link between dysregulated transthyretin and preeclampsia. Native transthyretin inhibits all preeclampsia-like features in the humanized mouse model, including new-onset proteinuria, increased blood pressure, glomerular endotheliosis, and production of anti-angiogenic factors. Our findings suggest that a focus on transthyretin structure and function is a novel strategy to understand and combat preeclampsia.Preeclampsia occurs in 5% to 8% of pregnancies worldwide and is a major cause of fetal and maternal morbidity and mortality.1–3 It is a heterogeneous disease with varied presentations from mild self-limited hypertension and proteinuria to severe forms with significant end-organ dysfunction and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets).3 Although the cause of preeclampsia and its appropriate treatment remain elusive, this syndrome has been proposed to reflect at least two stages of complications during pregnancy. These begin with preclinical manifestations at the maternal-fetal interface, followed by systemic clinical symptoms.1,2 Hypertension, proteinuria, and edema, with a variable degree of fetal growth restriction, are the cardinal features of preeclampsia.3 Because the placenta is the nutritional and immunological gateway to normal fetal development and pregnancy outcome, placenta-related events are believed to be central to the pathogenesis of this disease. Evidence exists for the release of disease-initiating molecules into maternal circulation that triggers the clinical symptoms.1,4 Placental and systemic anomalies reflected by circulating placental debris, inflammation, impaired remodeling of spiral arteries, placental hypoxia/ischemia, excess production of anti-angiogenic factors [soluble fms-like tyrosine kinase-1 (sFlt-1)], and soluble endoglin (sEng), and angiotensin receptor autoantibodies have all emerged as contributors to the pathophysiological characteristics of preeclampsia.2,4–14Preeclampsia has remained enigmatic because of lack of well-defined etiology and animal models. Although normal mice do not develop preeclampsia spontaneously, mouse models have been judged to be particularly useful to uterine diseases and pregnancy complications because many similarities in female reproduction and placentation have been identified between the two species.15 Moreover, their tractable genetics provide an effective way to probe mechanisms more deeply than many other species.15–17 We recently showed that sera from preeclamptic women could function as a source of novel causative factors that induced hypertension, proteinuria, and kidney pathological characteristics, as well as intrauterine growth restriction (IUGR), in IL-10−/− mice in a pregnancy-specific manner.18 IL-10 functions as a potent vascular and anti-inflammatory cytokine and has been shown to be present at significantly reduced levels in preeclampsia placental tissue.19,20 Preeclampsia serum (PES) was found to disrupt endovascular cross talk between trophoblasts and endothelial cells and to induce placental hypoxia and excess production of sFlt-1 and sEng,18 soluble factors known to precipitate maternal symptoms.21,22 These results from our serum-based humanized mouse model suggest that the pathophysiological characteristics of preeclampsia are more complex than previously thought and are likely to involve interactions and dysregulation of multiple factors. By using serum proteomic screening by surface-enhanced laser-desorption ionization-time-of-flight (SELDI-TOF), our results suggest that PES contains a reduced abundance of transthyretin, a plasma transport protein for the thyroid hormone, thyroxine, and retinol-binding protein.23 More important, transthyretin has been widely studied for its role in amyloid diseases associated with protein misfolding and aggregation, resulting in deposits of toxic, fibrillar aggregates in specific organs.24–26 Dysregulated or reduced transthyretin has also been implicated in Alzheimer disease, and overexpression of a wild-type human transthyretin transgene has been shown to ameliorate the disease in the transgenic murine model of human Alzheimer disease.27,28 Transthyretin in its native form assumes a homotetrameric quaternary configuration (approximately 14 kDa per monomer). Post-translational modifications of the monomer result in detection of several isoforms.29 Circulating transthyretin is also a validated marker of malnutrition and has a putative role in oocyte maturation and inflammation.30–32 Although the presence of transthyretin during implantation in mice and in the placenta and trophoblasts in humans has been reported,33,34 its functional role in normal pregnancy or adverse pregnancy outcomes has not been recognized. We hypothesize that transthyretin in preeclampsia is structurally and functionally dysregulated and contributes to the onset of this serious pregnancy complication. Herein, we present complementary in vitro and in vivo approaches, which show that endogenously altered transthyretin is a preeclampsia-causing agent and that native transthyretin has the ability to block the onset of preeclampsia-like features.  相似文献   
29.
INTRODUCTIONTracheal stenosis is a late and usually non-life threatening complication of surgical and percutaneous tracheostomies (PDT) as well as delayed endotracheal extubation.METHODSWe undertook a retrospective review of all patients who underwent a surgical tracheostomy over a 10 year period. Patients were included in the study if they had CT or MRI imaging of the tracheostomy site both pre-operatively and six or more weeks post operatively. Patients whose imaging was not available were excluded (n = 3) as were those patients who still had a tracheostomy in situ (n = 8). In total 91 patients were included in the study. In the same period 1170 surgical tracheostomies were performed by the maxillofacial surgeons. The images were analysed by a radiologist and the degree of stenosis reported.RESULTSAll 91 patients underwent a tracheostomy with a window. 83 patients did not demonstrate any stenosis. Looking at the remaining 8 patients with stenosis: 6 patients had stenosis of less than 25%, 1 patient had stenosis between 25-50% and 1 patient had stenosis greater than 50%. Both patients with stenosis greater than 25% had more than one surgical tracheostomy.CONCULSIONWe have shown that the risk of stenosis is 8.8%, lower than often quoted in literature, and when it occurs it is likely to be symptomatic only in severe stenosis. Our main risk of stenosis was repeat surgical tracheostomies which also seems to be linked to a greater degree of stenosis.  相似文献   
30.
Abstract

Background: Natural opiate users constitute a large proportion of opioid dependent individuals in India, and enjoy socio-cultural sanction in certain parts of the country. However, no study has assessed the pathways to care among this population in India.

Objective: To assess the pathways to care among treatment-seeking natural opiate dependent individuals.

Method: This cross sectional, explorative study was conducted at a tertiary care drug treatment centre located in North India. A total of 125 male participants aged >18?years, seeking treatment for natural opiate dependence from our outpatient clinic were included. A semi-structured proforma and WHO mental health encounter form was applied to assess socio-demographic, treatment details and pathways to care.

Results: The mean age was 46.17 (±11.98) years. Poppy husk (phukki/doda/posht) was the most common primary natural opiate used (84%). First point of treatment contact was addiction psychiatrist (n?=?90; 72%) in majority. First time treatment seeking was either by self-referral (60.8%) or referral by relatives and friends (24.8%) with mean time lag of 18.63?years after the onset.

Conclusion: Natural opiates dependent patients seek treatment late in the course of their illness, often directly from a tertiary addiction treatment centre. Barriers to seek treatment needs to be addressed.  相似文献   
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