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81.
Mary Courtney Moore Marta S. Smith Vikram P. Sinha John M. Beals M. Dodson Michael Scott J. Jacober Alan D. Cherrington 《Diabetes》2014,63(2):494-504
The impact of the novel basal insulin LY2605541 (LY) on hepatic and nonhepatic glucose uptake (non-HGU) was evaluated. Conscious dogs underwent euglycemic clamps with tracer and hepatic balance measurements. Clamp period infusions were peripheral venous regular insulin (0.1 nmol ⋅ kg−1 ⋅ h−1 [control], n = 6) or LY (bolus [nmol/kg], continuous [nmol ⋅ kg−1 ⋅ h−1]: 0.5, 0.5 [n = 6]; 0.375, 0.375 [n = 5]; 0.25, 0.25 [n = 4]), somatostatin, and glucose, as well as intraportal glucagon (basal). During the clamp, the dogs switched from net hepatic glucose output to uptake (rates reached 2.1 ± 1.2, 0.9 ± 2.1, 8.6 ± 2.3, and 6.0 ± 1.1 µmol ⋅ kg−1 ⋅ min−1 within 5 h in control, LY0.25, LY0.375, and LY0.5, respectively). Non-HGU in LY increased less than in control; the ratio of change from basal in non-HGU to change in net hepatic glucose balance, calculated when glucose infusion rates (GIRs) were ~20 µmol ⋅ kg-1 ⋅ min−1 in all groups, was higher in control (1.17 ± 0.38) versus LY0.25 (0.39 ± 0.33), LY0.375 (−0.01 ± 0.13), and LY0.5 (−0.09 ± 0.07). Likewise, the change from baseline in glucose Rd-to-Ra ratio was greatest in control (1.4 ± 0.3 vs. 0.6 ± 0.4, 0.5 ± 0.2, and 0.6 ± 0.2 in LY0.25, LY0.375, and LY0.5, respectively). In contrast to exogenously administered human insulin, LY demonstrated preferential hepatic effects, similar to endogenously secreted insulin. Therefore, the analog might reduce complications associated with current insulin therapy. 相似文献
82.
Andrew X. Zhu MD Darrell R. Borger MD Yuhree Kim MD David Cosgrove MD Aslam Ejaz MD Sorin Alexandrescu MD Ryan Thomas Groeschl MD Vikram Deshpande MD James M. Lindberg MD Cristina Ferrone MD Christine Sempoux MD Thomas Yau MD Ronnie Poon MD Irinel Popescu MD Todd W. Bauer MD T. Clark Gamblin MD Jean Francois Gigot MD Robert A. Anders MD Timothy M. Pawlik MD MPH PhD 《Annals of surgical oncology》2014,21(12):3827-3834
Background
The molecular alterations that drive tumorigenesis in intrahepatic cholangiocarcinoma (ICC) remain poorly defined. We sought to determine the incidence and prognostic significance of mutations associated with ICC among patients undergoing surgical resection.Methods
Multiplexed mutational profiling was performed using nucleic acids that were extracted from 200 resected ICC tumor specimens from 7 centers. The frequency of mutations was ascertained and the effect on outcome was determined.Results
The majority of patients (61.5 %) had no genetic mutation identified. Among the 77 patients (38.5 %) with a genetic mutation, only a small number of gene mutations were identified with a frequency of >5 %: IDH1 (15.5 %) and KRAS (8.6 %). Other genetic mutations were identified in very low frequency: BRAF (4.9 %), IDH2 (4.5 %), PIK3CA (4.3 %), NRAS (3.1 %), TP53 (2.5 %), MAP2K1 (1.9 %), CTNNB1 (0.6 %), and PTEN (0.6 %). Among patients with an IDH1-mutant tumor, approximately 7 % were associated with a concurrent PIK3CA gene mutation or a mutation in MAP2K1 (4 %). No concurrent mutations in IDH1 and KRAS were noted. Compared with ICC tumors that had no identified mutation, IDH1-mutant tumors were more often bilateral (odds ratio 2.75), while KRAS-mutant tumors were more likely to be associated with R1 margin (odds ratio 6.51) (both P < 0.05). Although clinicopathological features such as tumor number and nodal status were associated with survival, no specific mutation was associated with prognosis.Conclusions
Most somatic mutations in resected ICC tissue are found at low frequency, supporting a need for broad-based mutational profiling in these patients. IDH1 and KRAS were the most common mutations noted. Although certain mutations were associated with ICC clinicopathological features, mutational status did not seemingly affect long-term prognosis. 相似文献83.
84.
85.
Jigar N. Patel Amit Kumar Partap Singh Yadav Rajiv Chadha Vikram Datta Subhasis Roy Choudhury 《Journal of pediatric surgery》2018,53(8):1560-1565
Background/purpose
The anal position index (API) defines the normal anal position as the ratio of fourchette–anal distance to fourchette–coccyx distance for females and the scrotum–anal distance to scrotum‐coccyx distance for males. In this study, measurement of the API in newborns and infants with anorectal malformations (ARM), using the center of the midline anal dimple (AD) to represent the center of the proposed neoanus, was performed to assess whether or not the AD was located in a significantly abnormal position as correlated with the normal anal position.Methods
The cases comprised 65 consecutive newborn and infants with ARM, divided into 2 age-based groups (Group A: 1st day to 1 month; Group B: 1–12 months), without sacral or significant perineal abnormalities. Controls included an equal number of age and gender matched patients admitted for other conditions. The characteristics of the AD (‘well developed’ or ‘moderately developed’) as well as those of the midline perineal raphé in males and the perineal groove in females were also recorded.Results
Combining both age groups, the mean API ± SD was 0.41 ± 0.012 in male cases and 0.53 ± 0.07 in male controls (p value 0.003). The corresponding values for female cases and controls were 0.31 ± 0.09 and 0.36 ± 0.07 respectively (p = 0.040). In male newborns, the API in cases was significantly lower than the API in controls (p < 0.001). Combining both males and female newborns, the differences between the API in cases and controls was also statistically significant (p < 0.001). In older boys as well as in girls from both age groups, apart from cases of persistent cloaca, the API was lower in cases than in controls, especially in boys, although the difference was not statistically significant. On comparing the API in individual male ARM with that in male controls, cases of rectobulbar urethral fistula (RBUF) and rectovesical fistula had a statistically significant lower API (p < 0.001). In the 4 cases of persistent cloaca, the mean API (0.40 ± 0.1) was higher than the mean API in female controls and the AD was well developed with a well-delineated, narrow perineal groove. The majority (53/65; 81.53%) of patients had a ‘well developed’ AD. Twelve patients (18.47%) had a ‘moderately developed’ AD including 10 females and 2 males. There were 15 patients with a depressed AD (anal fossette); of these 12 (80%) were females. All boys had a well delineated perineal raphé in contrast to 10 girls (29.4% of total female ARM) who had a poorly delineated midline perineal groove.Conclusions
During definitive surgery for ARM, if the AD is taken as the site of the proposed neoanus, the neoanal position is likely to be anterior to the normal anal position in both males and females and especially so in males. Overall, girls with ARM appear to be more likely to have a relatively poorly developed and/ or depressed AD and a poorly delineated perineal groove.Type of study
Clinical Research.Level of evidence
Level III. 相似文献86.
Vikram L. Sundararaghavan Sivjot Binepal David E. Stec Puneet Sindhwani Terry D. Hinds 《Transplantation reviews (Orlando, Fla.)》2018,32(4):234-240
In patients with end-stage renal disease, kidney transplantation has been associated with numerous benefits, including increased daily activity, and better survival rates. However, over 20% of kidney transplants result in rejection within five years. Rejection is primarily due to a hypersensitive immune system and ischemia/reperfusion injury. Bilirubin has been shown to be a potent antioxidant that is capable of potentially reversing or preventing damage from reactive oxygen species generated from ischemia and reperfusion. Additionally, bilirubin has several immunomodulatory effects that can dampen the immune system to promote organ acceptance. Increased bilirubin has also been shown to have a positive impact on renal hemodynamics, which is critical post-transplantation. Lastly, bilirubin levels have been correlated with biomarkers of successful transplantation. In this review, we discuss a multitude of potentially beneficial effects that bilirubin has on kidney acceptance of transplantation based on numerous clinical trials and animal models. Exogenous bilirubin delivery or increasing endogenous levels pre- or post-transplantation may have therapeutic benefits. 相似文献
87.
Mahmoud B. Malas Jose Ignacio Leal Lorenzo Besma Nejim Todd M. Hanover Manish Mehta Vikram Kashyap Christopher J. Kwolek Richard Cambria 《Journal of vascular surgery》2019,69(6):1786-1796
ObjectiveWe report the 1-year outcomes of the Safety and Efficacy Study for Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial. This trial introduced a novel transcarotid neuroprotection system (NPS), the ENROUTE transcarotid NPS (Silk Road Medical Inc, Sunnyvale, Calif). Postoperative results demonstrated that the use of the ENROUTE transcarotid NPS is safe and effective. The aim of this study was to evaluate the safety of transcarotid artery revascularization (TCAR) and to present the 1-year outcomes.MethodsThis study is a prospective, single-arm clinical trial. Current enrollment occurs in 14 centers. Primary end points were incidence rates of ipsilateral stroke at 1 year after TCAR. Occurrence of stroke was ascertained by an independent Clinical Events Committee. Patients with anatomic or medical high-risk factors for carotid endarterectomy (CEA) were eligible to be enrolled in the ROADSTER trial.ResultsOverall, 165 patients were included in the long-term follow-up (112 of 141 patients from the pivotal phase and 53 of 78 patients from the extended access). Mean age was 73.9 years (range, 42.1-91.3 years). Patients aged 75 years and older were 43.3% of the cohort. The majority of patients were white (92.7%) and male (75.2%). Most patients were asymptomatic (79.9%). Anatomic risk factors were distributed as follows: contralateral carotid artery occlusion (11.0%), tandem stenosis of >70% (1.8%), high cervical carotid artery stenosis (25.0%), restenosis after CEA (25.6%), bilateral stenosis requiring treatment (4.3%), and hostile neck (14.6%). Medical high-risk criteria included two-vessel coronary artery disease (14.0%) and severe left ventricular dysfunction with ejection fraction <30% (1.8%). In general, 43.3% of patients had at least one anatomic high-risk factor, whereas 29.9% of patients had medical high-risk factors. Both subsets of factors were present simultaneously in 26.8% of the cohort. At 1-year follow-up, ipsilateral stroke incidence rate was 0.6%, and seven patients (4.2%) died. None of the deaths were neurologic in origin.ConclusionsTCAR with dynamic flow reversal had previously shown favorable 30-day perioperative outcomes. This excellent performance seems to extend to 1 year after TCAR as illustrated in this analysis. The promising results from the ROADSTER trial likely stem from the novel cerebral protection provided through the ENROUTE transcarotid NPS in comparison to distal embolic protection devices as well as the transcarotid approach's circumventing diseased aortic arch manipulation and minimizing embolization. TCAR offers a safe and durable revascularization option for patients who are deemed to be at high risk for CEA. 相似文献
88.
Bone Geometry,Volumetric Density,Microarchitecture, and Estimated Bone Strength Assessed by HR‐pQCT in Adult Patients With Hypophosphatemic Rickets 下载免费PDF全文
Vikram V Shanbhogue Stinus Hansen Lars Folkestad Kim Brixen Signe Sparre Beck‐Nielsen 《Journal of bone and mineral research》2015,30(1):176-183
Hypophosphatemic rickets (HR) is characterized by a generalized mineralization defect. Although densitometric studies have found the patients to have an elevated bone mineral density (BMD), data on bone geometry and microstructure are scarce. The aim of this cross‐sectional in vivo study was to assess bone geometry, volumetric BMD (vBMD), microarchitecture, and estimated bone strength in adult patients with HR using high‐resolution peripheral quantitative computed tomography (HR‐pQCT). Twenty‐nine patients (aged 19 to 79 years; 21 female, 8 male patients), 26 of whom had genetically proven X‐linked HR, were matched with respect to age and sex with 29 healthy subjects. Eleven patients were currently receiving therapy with calcitriol and phosphate for a median duration of 29.1 years (12.0 to 43.0 years). Because of the disproportionate short stature in HR, the region of interest in HR‐pQCT images at the distal radius and tibia were placed in a constant proportion to the entire length of the bone in both patients and healthy volunteers. In age‐ and weight‐adjusted models, HR patients had significantly higher total bone cross‐sectional areas (radius 36%, tibia 20%; both p < 0.001) with significantly higher trabecular bone areas (radius 49%, tibia 14%; both p < 0.001) compared with controls. In addition, HR patients had lower total vBMD (radius ?20%, tibia ?14%; both p < 0.01), cortical vBMD (radius ?5%, p < 0.001), trabecular number (radius ?13%, tibia ?14%; both p < 0.01), and cortical thickness (radius ?19%; p < 0.01) compared with controls, whereas trabecular spacing (radius 18%, tibia 23%; p < 0.01) and trabecular network inhomogeneity (radius 29%, tibia 40%; both p < 0.01) were higher. Estimated bone strength was similar between the groups. In conclusion, in patients with HR, the negative impact of lower vBMD and trabecular number on bone strength seems to be compensated by an increase in bone diameter, resulting in HR patients having normal estimates of bone strength. © 2014 American Society for Bone and Mineral Research. 相似文献
89.
90.
Marc Jennewein Matthew A Lewis Dawen Zhao Edward Tsyganov Nikolai Slavine Jin He Linda Watkins Vikram D Kodibagkar Sean O'Kelly Padmakar Kulkarni Peter P Antich Alex Hermanne Frank R?sch Ralph P Mason Philip E Thorpe 《Clinical cancer research》2008,14(5):1377-1385
PURPOSE: We recently reported that anionic phospholipids, principally phosphatidylserine, become exposed on the external surface of vascular endothelial cells in tumors, probably in response to oxidative stresses present in the tumor microenvironment. In the present study, we tested the hypothesis that a chimeric monoclonal antibody that binds phosphatidylserine could be labeled with radioactive arsenic isotopes and used for molecular imaging of solid tumors in rats. EXPERIMENTAL DESIGN: Bavituximab was labeled with (74)As (beta(+), T(1/2) 17.8 days) or (77)As (beta(-), T(1/2) 1.6 days) using a novel procedure. The radionuclides of arsenic were selected because their long half-lives are consistent with the long biological half lives of antibodies in vivo and because their chemistry permits stable attachment to antibodies. The radiolabeled antibodies were tested for the ability to image subcutaneous Dunning prostate R3227-AT1 tumors in rats. RESULTS: Clear images of the tumors were obtained using planar gamma-scintigraphy and positron emission tomography. Biodistribution studies confirmed the specific localization of bavituximab to the tumors. The tumor-to-liver ratio 72 h after injection was 22 for bavituximab compared with 1.5 for an isotype-matched control chimeric antibody of irrelevant specificity. Immunohistochemical studies showed that the bavituximab was labeling the tumor vascular endothelium. CONCLUSIONS: These results show that radioarsenic-labeled bavituximab has potential as a new tool for imaging the vasculature of solid tumors. 相似文献