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41.
Yadav PN Chaturvedi K Howells RD 《The Journal of pharmacology and experimental therapeutics》2007,320(3):1186-1194
This study was designed to test the hypothesis that inhibition of agonist-induced delta-receptor down-regulation would block the development of opioid tolerance in a cell-based model. A human embryonic kidney 293 cell line was established that expressed an epitope-tagged delta-opioid receptor (DOR). Treatment of DOR cells with Tyr-d-Ala-Gly-Phe-d-Leu-enkephalin (DADL) resulted in a time-dependent decrease in the B(max) of delta-opioid receptor binding sites and immunoreactive receptor protein. When cells were coincubated with the proteasome inhibitor N-benzyloxycarbonyl-l-leucyl-l-leucyl-l-leucinal (ZLLL) and DADL, the magnitude of the agonist-induced decrease in B(max) and immunoreactive receptor protein was reduced compared with DADL treatment alone. Acute treatment of DOR cells with DADL caused a 3-fold increase in the level of phosphorylated mitogen-activated protein (MAP) kinase. Prior exposure of DOR cells to DADL completely abrogated the agonist-induced activation of MAP kinase. When DOR cells were coincubated with DADL and ZLLL, the proteasome inhibitor prevented the loss of agonist activation of MAP kinase. Acute treatment of DOR cell membranes with DADL stimulated [(35)S]guanosine 5'-3-O-(thio-)triphosphate (GTPgammaS) binding. When DOR cells were preincubated with DADL, the agonist-induced increase in [(35)S]GTPgammaS binding was attenuated. Coincubation of ZLLL and agonist partially prevented the decreased responsiveness to agonist stimulation. The results of this study demonstrated that inhibition of agonist-induced down regulation with a proteasome inhibitor attenuated opioid tolerance in a cellular model, and suggest that coadministration of a proteasome inhibitor with chronic opioid agonist treatment may be useful for limiting opioid tolerance in vivo. 相似文献
42.
Health care services are being confronted by a daily dilemma of who can receive critical care and who cannot. In a palliative care clinic, this apprehension gets exemplified, as these patients have limited life expectancy. The head and neck region further makes things critical, as it comprises of all the sites through which the SARS‐CoV‐2 can be transmitted. This document strives to define the ways in which the head and neck cancer services can contribute to better patient care in a triage context. Practical steps suggested are protective equipment use, ensuring access to critical drugs (such as opioids), greater use of telemedicine consultations, discussing advance care plans, and embracing the role of a wider community support. 相似文献
43.
44.
Serum ferritin (SF) values 10 µg/l are diagnostic of absent Bone Marrow Iron (BMI) stores and therefore of iron deficiency (ID). However, SF, which may be elevated as a part of acute phase reaction, is an unreliable indicator of BMI stores in the setting of chronic disorders, making it difficult to diagnose ID in these patients. Thus, in chronic disorders (CD) such as tuberculosis, bone marrow examination is the only reliable way to establish ID. This study was done in order to identify levels of SF that would be indicative of absent BMI stores and also to study a combination of hematological and biochemical parameters that would be helpful in raising the predictive power of SF in patients of tuberculosis. Fifty-five tuberculosis patients were studied and classified into Iron Deplete (ID) and Iron Replete (IR) based on BMI. Raising the cut-off values of SF from 10 µg/l to 30 µg/l diagnosed 88% of ID cases correctly, as compared with 61% when cut-off levels of 10 µg/l were used. At cut-off values higher than 30 µg/l, the sensitivity was markedly reduced. Therefore, raising cut-off levels of SF to 30 µg/l was most effective in predicting absent BMI, especially in a population where ID is highly prevalent. Combination of SF 30 µg/l with mean corpuscular volume (MCV), erythrocyte sedimentation rate (ESR) and total iron binding capacity (TIBC) did not improve the predictive power of SF further. Also, 89.5% cases could be correctly classified by logistic regression equations using SF with ESR and C- reactive protein (CRP).Abbreviations
SF
Serum ferritin
-
BMI
Bone marrow iron
-
ID
Iron deplete
-
IR
Iron replete
-
CD
Chronic disorders
-
MCV
Mean corpuscular volume
-
TIBC
Total iron binding capacity
-
ESR
Erythrocyte sedimentation rate
-
ACD
Anemia of chronic disorders
-
IDA
Iron deficiency anemia
-
Hb
Hemoglobin concentration
-
TLC
Total leukocyte count
-
RBC
Red blood cell
-
RDW
Red cell distribution width
-
% TS
Percent transferrin saturation
-
SI
Serum iron 相似文献
45.
D Kuh R Hardy N Chaturvedi M E J Wadsworth 《International journal of obesity (2005)》2002,26(1):40-47
OBJECTIVE: To examine the relationship of adult abdominal obesity to birth weight, childhood growth and lifetime socioeconomic circumstances. METHODS: A cohort of 3200 men and women with measured waist and hip circumference, height and weight at age 43 who have been followed since their birth in March 1946 in England, Scotland and Wales. Regression models were used to examine mean waist-hip ratio and waist circumference in relation to prospective measures of birth weight, weight relative to height in childhood at ages 4, 7, 11 and 15 and adult body mass index, and to test the independent and interactive nature of the associations and adjust for childhood and adult social class. RESULTS: There was a small inverse effect of birth weight on waist-hip ratio (P=0.037) but not waist circumference in women, after adjustment for current body size. Relative weight at age 7 was inversely related to waist-hip ratio and waist circumference in men (P<0.001 for both) and waist circumference in women (P=0.007) after adjustment for current body size. These relationships were attenuated in men of large body mass index (P<0.01 for interactions between relative weight at 7 y and body mass index in both cases) but were not modified by birth weight. Relative weights at other ages showed similar patterns to those observed at age 7, the effect being weakest at age 4. These findings were independent of lifetime socioeconomic circumstances. CONCLUSION: This study found a small prenatal inverse effect of fetal growth on adult waist-hip ratio due to a reduced hip size. There was also an inverse postnatal effect of childhood growth such that for any given adult body size those who had been lighter in childhood were more at risk of abdominal obesity. These relationships were independent of childhood socioeconomic circumstances and support the idea that insulin resistance may be linked to low weight in childhood. 相似文献
46.
Background
Current reports on nipple-sparing mastectomy (NSM) are limited to single-institution series. We use the National Cancer Institute's Surveillance, Epidemiology, and End Results database to report on the national experience with NSM.Methods
Population-level deidentified data were extracted from the Surveillance, Epidemiology, and End Results database. All female breast cancer patients treated with NSM from 2005 to 2009 were included. Case analysis was performed with respect to demographic and oncologic characteristics.Results
Four hundred forty-nine patients underwent therapeutic NSM; this number increased from 66 patients in 2005 to 133 in 2009. Patients were distributed across 16 regions, although nearly 50% were from a region of California. Tumor diameter was <2 cm in 224 patients (50%). Lymph nodes were positive in 59 patients (13%), while radiation was delivered to 74 patients (16%).Conclusions
NSM use has been increasing over the past several years. A majority of patients have tumor size <2 cm, although the number of patients with tumor size ≥2 cm has increased over time. Further population-based studies of NSM may benefit from collection of oncologic data such as tumor-to-nipple distance and tumor location. 相似文献47.
Jeffrey H. Kozlow Jeffrey Lisiecki Michael N. Terjimanian Jacob Rinkinen Robert Cameron Brownley Shailesh Agarwal Stewart C. Wang Benjamin Levi 《The Journal of surgical research》2014
Background
Sternal reconstruction with vascularized flaps is central to the management of sternal wound infections and mediastinitis but carries a high risk of complications. There is a need to identify reliable predictors of complication risk to help inform patients and clinicians in preparation for surgery. Unfortunately, body mass index and serum albumin may not be reliable predictors of complication rates. Analytic morphomics provides a robust quantitative method to measure patients' obesity as it pertains to their risk of complications in undergoing sternal reconstruction.Methods
We identified 34 patients with preoperative computed tomography scans of the abdomen from a cohort of sternal reconstructions performed between 1997 and 2010. Using semiautomated analytic morphomics, we identified the patients' skin and fascia layers between the ninth and 12th thoracic spine levels; from these landmarks, we calculated morphomic measurements of the patients' abdomens, including their total body cross sectional area and the cross sectional area of their subcutaneous fat. We obtained the incidence of complications from chart review and correlated the incidence of complications (including seroma, hematoma, recurrent wounds, mediastinitis, tracheostomy, and death) with patients' morphomic measurements.Results
Sixty-two percent of patients (n = 21) suffered complications after their operation. Those who suffered from complications, relative to those who did not have complications, had increased visceral fat area (12,547.2 mm2versus 6569.9 mm2, P = 0.0080), subcutaneous fat area (16,520.2 mm2versus 8020.1 mm2, P = 0.0036), total body area (91,028.6 mm2versus 67,506.5 mm2, P = 0.0022), fascia area (69,238.4 mm2versus 56,730.9 mm2, P = 0.0118), total body circumference (1101.8 mm versus 950.2 mm, P = 0.0017), and fascia circumference (967.5 mm versus 868.1 mm, P = 0.0077). We also demonstrated a significant positive correlation between the previously mentioned morphomic measurements and the incidence of complications in multivariate logistic regression models, with odds ratios ranging from 1.19–3.10 (P values ranging from 0.010–0.022).Conclusions
Increases in abdominal morphomic measurements correlate strongly with the incidence of complications in patients undergoing sternal reconstruction. This finding may influence preoperative risk stratification and surgical decision making in this patient population. 相似文献48.
Ankit A. Chaturvedi Roger M.L.M. Lomme Thijs Hendriks Harry van Goor 《The Journal of surgical research》2014
Background
Ultrapure alginate gel is promising in terms of adhesion prevention. Because anti-adhesive barriers have been shown to disturb healing of bowel anastomoses, the effect of ultrapure alginate gel on the repair of colon anastomoses was studied.Materials and methods
In 102 male Wistar rats, a 0.5-cm segment was resected from the descending colon and continuity was restored by an inverted single-layer end-to-end anastomosis. Animals were randomized into a control, an alginate gel, and a sodium hyaluronate carboxymethyl cellulose film group, each n = 34. Half of each group was sacrificed at day 3 and 7 postoperatively. Anastomotic strength was assessed by measuring both bursting pressure and breaking strength. Hydroxyproline content was measured and histologic analysis was performed. The incidence of adhesion and abscess formation was scored at sacrifice.Results
No difference in either anastomotic-bursting pressure or breaking strength was found between experimental groups and the controls at any time point. Both the incidence of adhesion formation (35% versus 71%, P = 0.007) and the adhesion score (0.38 versus 0.79, P = 0.009) were significantly lower in the alginate gel group than in the controls. The abscess rate was higher (46% versus 18%, P = 0.030) in the hyaluronate carboxymethyl cellulose group than in the controls and unchanged in the alginate gel group.Conclusions
While reducing adhesion formation, ultrapure alginate gel does not interfere with the development of colonic anastomotic strength during the crucial early healing period. 相似文献49.
Nerve-sparing robotic radical hysterectomy: our technique 总被引:1,自引:0,他引:1
Shailesh P. Puntambekar Akhil Lawande Riddhi Desai Rahul Kenawadekar Saurabh Joshi Geetanjali Agarwal Joshi 《Journal of robotic surgery》2014,8(1):43-47
Robotic surgery is now becoming accepted for treatment of gynaecological malignancies. Nerve preservation during radical hysterectomy is increasingly being offered due to improved post-operative bladder and sexual function. We aimed to demonstrate the feasibility of performing a nerve-sparing radical hysterectomy robotically and to assess the oncological and functional outcomes associated with this surgery. Between August 2011 and January 2013, a total of 12 non-consecutive patients underwent robotic surgery for early stage cervical cancer at our institution. Patients comprising FIGO stage IA2 to IB1 were treated with nerve-sparing robotic radical hysterectomy using a C1 (Querleu–Morrow classification) type technique. The feasibility, operative time, blood loss, oncological outcome and post-operative bladder function were assessed. All the procedures were completed robotically without conversion to laparoscopy or laparotomy. The mean age of the patients was 56 years (range 44–76) and their mean body mass index was 22.6 kg/m2 (range 18.1–26.4). The mean operative time was 156 min (range 120–250); the mean blood loss was 120 ml (50–250). The Foley catheter was removed on the third post-operative day, with full recovery of bladder function in all patients except one who required prolonged catheterisation for 3 weeks. Residual urine was 40 ml (range 30–80). Parametrial margins of 2.5–3 cm, distal vaginal margins of 2–2.5 cm and a mean nodal harvest of 24 (range 18–30) were achieved. The mean hospital stay was 3 days (range 2–6). The median follow-up is 12 months. There is no loco-regional recurrence. All the patients are sexually active. Robotic nerve-sparing radical hysterectomy is technically feasible to perform, and is oncologically safe for early stage cervical carcinoma. 相似文献
50.
Akhil Lawande Rahul Kenawadekar Riddhi Desai Chaitanya Malireddy Kathya Nallapothula Shailesh P. Puntambekar 《Journal of robotic surgery》2014,8(1):93-96