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排序方式: 共有1402条查询结果,搜索用时 46 毫秒
71.
Chidambaram Ramanathan Thomas Lackie Drake H. Williams Paul S. Simone Yufeng Zhang Richard J. Bloomer 《Nutrients》2022,14(2)
As a redox-sensitive coenzyme, nicotinamide adenine dinucleotide (NAD+) plays a central role in cellular energy metabolism and homeostasis. Low NAD+ levels are linked to multiple disease states, including age-related diseases, such as metabolic and neurodegenerative diseases. Consequently, restoring/increasing NAD+ levels in vivo has emerged as an important intervention targeting age-related neurodegenerative diseases. One of the widely studied approaches to increase NAD+ levels in vivo is accomplished by using NAD+ precursors, such as nicotinamide mononucleotide (NMN). Oral administration of NMN has been shown to successfully increase NAD+ levels in a variety of tissues; however, it remains unclear whether NMN can cross the blood–brain barrier to increase brain NAD+ levels. This study evaluated the effects of oral NMN administration on NAD+ levels in C57/B6J mice brain tissues. Our results demonstrate that oral gavage of 400 mg/kg NMN successfully increases brain NAD+ levels in mice after 45 min. These findings provide evidence that NMN may be used as an intervention to increase NAD+ levels in the brain. 相似文献
72.
C A McCloskey G V Ramani M A Mathier P R Schauer G M Eid S G Mattar A P Courcoulas R Ramanathan 《Surgery for obesity and related diseases》2007,3(5):503-507
BACKGROUND: Longstanding morbid obesity can be associated with severe cardiomyopathy. However, the safety and efficacy of bariatric surgery in patients with severe cardiomyopathy has not been studied, and the effect of surgical weight loss on postoperative cardiac function is also unknown. In addition, morbidly obese patients have significantly increased mortality associated with cardiac transplantation, often precluding them from becoming recipients. METHODS: A retrospective study of patients with a left ventricular ejection fraction < or =35% who underwent bariatric surgery (1998-2005) was performed. Short-term morbidity/mortality, length of stay, excess weight loss, pre- and postoperative left ventricular ejection fraction, and New York Heart Association (NYHA) functional class were assessed. RESULTS: A total of 14 patients (10 men and 4 women) with a mean preoperative body mass index of 50.8 +/- 2.04 kg/m(2) underwent bariatric surgery (10 underwent laparoscopic Roux-en-Y gastric bypass, 1 open Roux-en-Y gastric bypass, 2 sleeve gastrectomy, and 1 laparoscopic gastric banding). The complications were pulmonary edema in 1, hypotension in 1, and transient renal insufficiency in 2. The median length of stay was 3.0 days (range 2-9). The mean excess weight loss at 6 months was 50.4%, with a decrease in the mean body mass index from 50.8 +/- 2.04 kg/m(2) to 36.8 +/- 1.72 kg/m(2). The mean left ventricular ejection fraction at 6 months had significantly improved from 23% +/- 2% to 32% +/- 4% (P = .04), correlating with improved functional capacity, as measured by the NYHA classification. Preoperatively, 2 patients (14%) had an NYHA classification of IV, 6 (43%) a classification of III, and 6 (43%) a classification of II. At 6 months postoperatively, no patient had an NYHA classification of IV, 2 (14%) had a classification of III, and 12 (86%) an NYHA classification of II. Two patients had undergone cardiac transplant evaluations preoperatively and underwent successful transplantation after weight loss. CONCLUSION: The results of our study have shown that bariatric surgery for patients with cardiomyopathy is feasible and effective. Surgically induced weight loss results in both subjective and objective improvement in cardiac function. In addition, surgical weight loss can provide a bridge to transplantation in patients who were prohibited secondary to their morbid obesity. 相似文献
73.
Ramanathan AK Nader ND Dryjski ML Dosluoglu HH Cherr GS Curl GR Kuritzky AS Harris LM 《Vascular》2011,19(2):97-104
This study compares outcomes of basilic and cephalic vein fistulas for hemodialysis. A retrospective review of arteriovenous fistulas in a university hospital system was performed using charts and hemodialysis records. Patency and demographic data were assessed with life table analysis. One hundred fifty-six patients (88 males; 68 females) underwent creation of 172 autogenous fistulas (mean age 61 years; mean follow-up 78 weeks). There were 101 basilic vein transpositions and 71 cephalic vein fistulas. Primary patency did not differ significantly, while assisted primary patency was significantly better for basilic vein fistulas at one year (73% versus 53%: P = 0.024). Secondary patency was significantly better for basilic fistulas through three years (58% versus 52%; P = 0.027). Primary failure (thrombosis before access or failed maturation) was significantly higher for cephalic than basilic fistulas (28% versus 13%; P = 0.01). Maturation time, usage time and complications were not significantly significant. Thirty-three (33%) basilic vein-based fistulas and 12 (17%) cephalic vein fistulas required revision during follow-up. Basilic vein-based fistulas perform as well as or better than cephalic vein-based fistulas in terms of patency, maturation time, and usage time and complication rates, though requiring more re-interventions. 相似文献
74.
Pritam Chanda Lara Sucheston Aidong Zhang Murali Ramanathan 《European journal of human genetics : EJHG》2009,17(10):1274-1286
We developed an information-theoretic metric called the Interaction Index for prioritizing genetic variations and environmental variables for follow-up in detailed sequencing studies. The Interaction Index was found to be effective for prioritizing the genetic and environmental variables involved in GEI for a diverse range of simulated data sets. The metric was also evaluated for a 103-SNP Crohn''s disease dataset and a simulated data set containing 9187 SNPs and multiple covariates that was modeled on a rheumatoid arthritis data set. Our results demonstrate that the Interaction Index algorithm is effective and efficient for prioritizing interacting variables for a diverse range of epidemiologic data sets containing complex combinations of direct effects, multiple GGI and GEI. 相似文献
75.
Vijayakumar Raju Sundar Ramanathan Raman Manjeri Lakshmanan Natarajan Subramanian 《Indian Journal of Thoracic and Cardiovascular Surgery》2010,26(2):167-169
Secondary involvement of the heart and pericardium by systemic lymphoma is well documented. Primary Cardiac lymphomas (PCL)
are extremely rare. Incidence of PCL is increasing in immunocompromised patients. However PCL in immunocompetent is much rarer.
We report such a case of PCL in an immunocompetent elderly female masquerading as right atrial myxoma causing complete heart
block which was surgically debulked successfully. Her rhythm resumed to Sinus rhythm following surgical debulking. Immunohistochemistry
of the excised tumour revealed Diffuse Large B cell lymphoma. With combination chemotherapy, she is symptom free on six months
follow up. 相似文献
76.
R. Ramanathan L. Reyderman A.-D. Su N. Alvarez S. K. Chowdhury K. B. Alton 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(7):770-787
The absorption, metabolism and excretion of desloratadine (DL, Clarinex®) were characterized in six healthy male volunteers. Subjects received a single oral 10-mg dose of [14C]DL (~104?µCi). Blood, urine and feces were collected over 240?h. DL was well absorbed; drug-derived radioactivity was excreted in both urine (41%) and feces (47%). With the exception of a single subject, DL was extensively metabolized; the major biotransformation pathway consisted of hydroxylation at the 3 position of the pyridine ring and subsequent glucuronidation (3-OH-DL-glucuronide or M13). In five of the six subjects, DL was slowly eliminated (mean t½?=?19.5?h) and persisted in the plasma for 48–120?h post-dose. This is in contrast to a t½ of ~110?h and quantifiable plasma DL concentrations for the entire 240-h sampling period in one subject, who was identified phenotypically as a poor metabolizer of DL. This subject also exhibited correspondingly lower amounts of M13 in urine and 3-OH-DL (M40) in feces. Disposition of DL in this subject was characterized by slow absorption, slow metabolism and prolonged elimination. Further clinical studies confirmed the lack of safety issues associated with polymorphism of DL metabolism (Prenner et al. 2006, Expert Opinion on Drug Safety, 5: 211–223). 相似文献
77.
78.
79.
Oxaliplatin pharmacokinetics and pharmacodynamics in adult cancer patients with impaired renal function. 总被引:1,自引:0,他引:1
Chris H Takimoto Martin A Graham Graham Lockwood Chee M Ng Andrew Goetz Dennis Greenslade Scot C Remick Sunil Sharma Sridhar Mani Ramesh K Ramanathan Timothy W Synold James H Doroshow Anne Hamilton Daniel L Mulkerin Percy Ivy Merrill J Egorin Jean L Grem 《Clinical cancer research》2007,13(16):4832-4839
PURPOSE: To characterize the pharmacokinetics and pharmacodynamics of oxaliplatin in cancer patients with impaired renal function. EXPERIMENTAL DESIGN: Thirty-four patients were stratified by 24-h urinary creatinine clearance (CrCL) into four renal dysfunction groups: group A (control, CrCL, >or=60 mL/min), B (mild, CrCL, 40-59 mL/min), C (moderate, CrCL, 20-39 mL/min), and D (severe, CrCL, <20 mL/min). Patients were treated with 60 to 130 mg/m2 oxaliplatin infused over 2 h every 3 weeks. Pharmacokinetic monitoring of platinum in plasma, plasma ultrafiltrates, and urine was done during cycles 1 and 2. RESULTS: Plasma ultrafiltrate platinum clearance strongly correlated with CrCL (r2 = 0.712). Platinum elimination from plasma was triphasic, and maximal platinum concentrations (Cmax) were consistent across all renal impairment groups. However, only the beta-half-life was significantly prolonged by renal impairment, with values of 14.0 +/- 4.3, 20.3 +/- 17.7, 29.2 +/- 29.6, and 68.1 h in groups A, B, C, and D, respectively (P = 0.002). At a dose level of 130 mg/m2, the area under the concentration time curve increased in with the degree of renal impairment, with values of 16.4 +/- 5.03, 39.7 +/- 11.5, and 44.6 +/- 14.6 mug.h/mL, in groups A, B, and C, respectively. However, there was no increase in pharmacodynamic drug-related toxicities. Estimated CrCL using the Cockcroft-Gault method approximated the measured 24-h urinary CrCL (mean prediction error, -5.0 mL/min). CONCLUSIONS: Oxaliplatin pharmacokinetics are altered in patients with renal impairment, but a corresponding increase in oxaliplatin-related toxicities is not observed. 相似文献
80.
OBJECTIVE: To compare objectively the pain associated with tubal occlusion by Silastic rings versus electrocoagulation during laparoscopic tubal ligation under local anesthesia. METHODS: Consecutive patients scheduled for laparoscopic tubal ligation under local anesthesia were randomized to Silastic rings (N = 50) or electrocoagulation (N = 52) as the method of tubal occlusion. Sterilization was performed under local anesthesia in a standard fashion. Bupivacaine 0.5% was used as the local anesthetic agent. Operative pain was measured based on intraoperative anesthesia requirements and a modified McGill pain questionnaire. This questionnaire was used to assess pain at 15 minutes, 1 hour, and 24 hours postoperatively. RESULTS: Demographics were similar for the two groups. Operative time was shorter in the Silastic-ring group (16.7 versus 21.8 minutes; P = .001), and this group also required less intraoperative anesthesia (P = .004). There were no statistical differences between the groups in self-reported pain intraoperatively or postoperatively. No patient in either group required antiemetics or pain medication in the recovery room. CONCLUSION: Silastic rings appear preferable to bipolar electrocoagulation for laparoscopic tubal sterilization under local anesthesia when long-acting local agents are used for tubal anesthesia. 相似文献