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41.
Ata Mahmoodpoor Hadi Hamishehkar Kamran Shadvar Mohammadtaghi Beigmohammadi Afshin Iranpour Sarvin Sanaie 《Indian Journal of Critical Care Medicine》2016,20(2):67-71
Background and Aims:
The association between hyperglycemia and mortality is believed to be influenced by the presence of diabetes mellitus (DM). In this study, we evaluated the effect of preexisting hyperglycemia on the association between acute blood glucose management and mortality in critically ill patients. The primary objective of the study was the relationship between HbA1c and mortality in critically ill patients. Secondary objectives of the study were relationship between Intensive Care Unit (ICU) admission blood glucose and glucose control during ICU stay with mortality in critically ill patients.Materials and Methods:
Five hundred patients admitted to two ICUs were enrolled. Blood sugar and hemoglobin A1c (HbA1c) concentrations on ICU admission were measured. Age, sex, history of DM, comorbidities, Acute Physiology and Chronic Health Evaluation II score, sequential organ failure assessment score, hypoglycemic episodes, drug history, mortality, and development of acute kidney injury and liver failure were noted for all patients.Results:
Without considering the history of diabetes, nonsurvivors had significantly higher HbA1c values compared to survivors (7.25 ± 1.87 vs. 6.05 ± 1.22, respectively, P < 0.001). Blood glucose levels in ICU admission showed a significant correlation with risk of death (P < 0.006, confidence interval [CI]: 1.004–1.02, relative risk [RR]: 1.01). Logistic regression analysis revealed that HbA1c increased the risk of death; with each increase in HbA1c level, the risk of death doubled. However, this relationship was not statistically significant (P: 0.161, CI: 0.933–1.58, RR: 1.2).Conclusions:
Acute hyperglycemia significantly affects mortality in the critically ill patients; this relation is also influenced by chronic hyperglycemia. 相似文献42.
43.
Afshin A. Divani Tamara L. Berezina Gabriela Vazquez Sergey B. Zaets Ramachandra Tummala Adnan I. Qureshi 《Annals of biomedical engineering》2009,37(12):2428-2435
The objective of this study was to assess the effect of flow diversion by external carotid artery (ECA) occlusion on ipsilateral
regional cerebral blood flow (rCBF). Local cerebral hyperperfusion in rats (n = 12) was induced by ligating the right ECA. Ipsilateral rCBF was determined pre- and post-ligation for 120 min using a laser
Doppler flow meter. Sham animals (n = 6) were subjected to the craniotomy without ligation of the right ECA. In a separate series of rats (n = 5), brain tissue oxygen levels (pO2) in the right and left brain hemispheres were determined before and 90 min after ligation of the right ECA using a tissue
oxygenation monitoring unit. We investigated the effect of ECA occlusion hemispheric changes in rCBF in one clinical case
as a proof of concept. Ligation of ECA resulted in a statistically significant increase in rCBF on the ipsilateral side compared
to the sham-operated rats (p < 0.0001). On average we observed a 34% increase (95% CI: 24–45%) in rCBF in the ipsilateral territory in the treated group
compared with sham-operated rats. There was no significant variation in MAP for the treated animals. Vascular permeability
and cerebral water content in the right hemisphere after ligation of ECA did not significantly differ from the contralateral
hemisphere. Ipsilateral hemisphere tissue pO2 was significantly higher compared to the contralateral area (p < 0.002) post-ligation or to the ipsilateral area (p < 0.001) prior to ligation. In the clinical case, occlusion of ECA resulted in 3.6% and 12.1% increase in peak value and
rise-time of the time-density curves. Flow diversion by temporary occlusion of the ECA can result in increased rCBF and cerebral
pO2 on the ipsilateral side. The strategy may represent a viable option to augment rCBF in focal cerebral ischemia. 相似文献
44.
Bacteria and pathogenesis of human salivary calculus 总被引:2,自引:0,他引:2
Teymoortash A Wollstein AC Lippert BM Peldszus R Werner JA 《Acta oto-laryngologica》2002,122(2):210-214
The exact cause of salivary calculus formation is unknown and the aim of this study was to ascertain whether bacteria play a role. Sialoliths from nine patients with chronic obstructive sialadenitis of the submandibular gland were analysed. Bacterial gene fragments were amplified from DNA extracted from salivary calculi by means of polymerase chain reaction using a universal bacterial primer pair. Comparative 16S ribosomal RNA sequence analysis was used for identification. We detected and identified oral bacteria (predominantly Streptococcus species) in all samples. The present results suggest a potential role for bacteria in the etiopathogenesis of sialolithiasis. 相似文献
45.
Effect of allogeneic Schwann cell transplantation on peripheral nerve regeneration 总被引:24,自引:0,他引:24
Transplantation of allogeneic Schwann cells (SC) would make it feasible to reconstruct immediately peripheral nerve defects, compared to using autologous SC; however, this treatment modality has not been adequately evaluated. The aim of this study was to characterize and compare the effects of allogeneic versus syngeneic SC transplantation following peripheral nerve injury. Polyhydroxybutyrate conduits were used to bridge a 10-mm gap in the rat sciatic nerve. The conduits were filled with alginate hydrogel with or without cultured allogeneic or syngeneic genetically labeled SC, without the use of immunosuppressive therapy, and examined after 2, 3, and 6 weeks with 5-bromo-4-chloro-3-indoyl-beta-D-galactosidase chemical staining and immunohistochemistry to quantify SC migration into the conduit, axonal regeneration, the state of SC differentiation, and the expression of major histocompatibility complexes (MHC) I and II, as well as to quantify macrophage and B- and T-lymphocyte infiltration. Allogeneic SC were rejected by 6 weeks, whereas syngeneic SC could still be identified. Allogeneic and syngeneic SC equally enhanced the axonal regeneration distance but the quantity of axons was greater using syngeneic SC. The ingrowth of SC into the conduits containing allogeneic SC was similar to that observed in the presence of syngeneic SC, indicating the absence of deleterious immune response. SC continued to express phenotypic markers of nonmyelination and these were highest in conduits with allogeneic SC. Expression of MHC I and II was higher in the conduits with allogeneic SC at 3 weeks and without significant difference in the number of macrophages and lymphocytes, except at 6 weeks, when there was a larger number of lymphocytes using syngeneic SC. In conclusion, allogeneic SC enhanced axonal regeneration distance and did not induce a deleterious immune response. In a clinical setting the immediate availability of allogeneic SC for transplantation may compensate for the better outcome achieved by the use of autologous SC that require a longer preparation time in culture. 相似文献
46.
Afshin Dowlati Kelly Robertson Tomas Radivoyevitch John Waas Nicholas P Ziats Paul Hartman Fadi W Abdul-Karim Jay K Wasman Jack Jesberger Jonathan Lewin Keith McCrae Percy Ivy Scot C Remick 《Clinical cancer research》2005,11(21):7938-7944
PURPOSE: To determine the biological modulatory dose of SU5416, we employed a novel trial design, where "dose de-escalation" was based on demonstrable biological changes observed at the maximum tolerated dose. If such an effect was shown, dose de-escalation to a predefined dose level would occur to determine if the lower dose exhibited the same amount of pharmacodynamic effect as the higher dose. EXPERIMENTAL DESIGN: Ten patients with advanced solid tumors were enrolled at each dose level. One of the following pharmacodynamic effects was considered significant: (a) a 35% decrease in microvessel density in sequential tumor biopsies and (b) a 35% decrease in blood flow within tumor as assessed by dynamic contrast-enhanced magnetic resonance imaging. In addition, soluble E-selectin, soluble intercellular adhesion molecule, soluble vascular cell adhesion molecule, and plasma vascular endothelial growth factor were measured sequentially. RESULTS: Nineteen patients were enrolled. Sequential tumor biopsies in all evaluable patients showed an increase in microvessel density. Only one patient met the intended pharmacodynamic end point of >35% reduction in blood flow. There was a significant increase in both soluble E-selectin and soluble intercellular adhesion molecule levels pretreatment versus levels at the time of removal of patients from study (P = 0.04 and P = 0.0007, respectively). Levels of serum fibrinogen rose with therapy. There was a trend toward increase in plasma vascular endothelial growth factor levels. CONCLUSION: SU5416 does not result in decreased blood flow in tumors or a decrease in microvessel density. This corresponds to the lack of clinical activity seen with this agent. Our clinical trial design termed dose de-escalation is a novel approach to determine the in vivo biological effects of targeted therapies in cancer patients. 相似文献
47.
Treatment of hypoplastic left heart syndrome through staged repairs has resulted in patients surviving into adulthood. Use of either aortic or pulmonary homografts in performing the neoaortic reconstruction has become the standard of practice with relatively few problems. We report the case of an asymptomatic adolescent boy who had an enlarging neoaortic aneurysm and mild neoaortic regurgitation develop after undergoing a stage I Norwood procedure using a pulmonary homograft. Given the risk for rupture and a concern for further functional deterioration of the neoaortic valve, the patient underwent repair. Histologic examination showed a striking accumulation of myxoid material as well as abnormal vasculature in both the native and engrafted portions of the neoaorta. 相似文献
48.
Harrison D Lloyd-Smith R Khazei A Hunte G Lepawsky M 《Current sports medicine reports》2005,4(5):275-281
Primary care and sports medicine physicians are frequently consulted on medical clearance for prospective recreational divers.
We discuss four common and controversial medical conditions—asthma, diabetes mellitus, coronary artery disease, and patent
foramen ovale—as they relate to fitness to dive. For each condition we review the relevant anatomy and physiology, current
recommendations, and the pertinent medical literature. Finally, we offer evidence-based recommendations regarding fitness
to dive for potential divers with these conditions. 相似文献
49.
Khalafi A Landsman AS Lautenschlager EP Kelikian AS 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2005,26(7):550-555
BACKGROUND: The aim of this study was to evaluate plantar pressure changes after second metatarsal neck osteotomy using the Weil technique. METHODS: Six below-knee cadaver specimens were used. Each specimen was held in a custom-built apparatus and loaded to 500 N for a period of 3 seconds. Using a computerized Musgrave pedobarograph, pressure measurements were made before and after osteotomy in both neutral and 45-degree heel rise positions. All osteotomies were made at an angle of approximately 20 degrees relative to the long axis of the metatarsal shaft. The metatarsal heads were displaced proximally by 5 mm and fixed with a single Kirschner wire. RESULTS: After osteotomy there was an average decrease in pressure beneath the second metatarsal from 70.6 to 45.1 kPa in neutral and from 813.0 to 281.4 kPa in heel rise, representing statistically significant (p < or = 0.05) decreases of 36% and 65%, respectively. There also were significant decreases beneath the third metatarsal in both neutral (39%) and heel rise (37%), and beneath the fourth metatarsal in neutral position (28%). A significant pressure increase occurred beneath the first metatarsal in neutral (23%). No significant pressure changes occurred under the fifth metatarsal in either position. CONCLUSION: Overall, our results indicated that the Weil metatarsal neck osteotomy is effective at offloading the second metatarsal head at neutral and heel rise positions. 相似文献
50.
Jawad?F.?KirmaniEmail author Nazli?Janjua Ammar?Al Kawi Shafiuddin?Ahmed Ismail?Khatri Ali?Ebrahimi Afshin?A.?Divani Adnan?I.?Qureshi 《Neurotherapeutics》2005,2(2):304-323
Rapid advances in the field of interventional neurology and the development of minimally invasive techniques have resulted
in a great expansion of potential therapeutic applications. We discuss therapeutic interventional neurology as applied in
clinical practice in one of the two possible ways: 1) embolization leading to occlusion of blood vessels; and 2) revascularization
leading to reopening of blood vessels. These procedures can be applied to a broad range of cerebrovascular diseases. In the
first section of this review, we will explore the evolution of these interventions to occlude aneurysms, arteriovenous malformations,
neurovascular tumors, and injuries. In the second section, revascularization in acute ischemic stroke, stenosis, and dural
venous thrombosis will be discussed. 相似文献