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91.
Joseph A. Awad MD Eun Y. Lee MD Timothy C. Wang MD Katherine Deschryver-Kecskemeti MD Dr Ray E. Clouse MD 《Digestive diseases and sciences》1990,35(3):317-320
Gastric mucosal thickening of variable degree occurs in the vicinity of gastric carcinomas and is possibly related to simultaneous tumor expression of epidermal growth factor and its receptor. Seventeen cases in which both endoscopic biopsy and subsequent resection for gastric carcinoma had been performed were studied to see if putative tumor-related mucosal thickening had an effect on endoscopic biopsy sensitivity. Biopsy fragment positivity rate was greater in cases with exophytic, protruding tumor masses (46.8± 8.5%) than in all other cases (17.0± 4.7%; P=0.02). Thickness of nontumorous mucosa adjacent to carcinomas did not significantly affect the biopsy fragment positivity rate in cases with exophytic masses (thin subgroup, 51.0±16.2%; thick subgroup, 44.0±10.8%; P=0.7) but did reduce the positivity rate significantly (P=0.05) in ulcerative or infiltrative tumors without exophytic components (thin subgroup, 23.3±4.1%; thick subgroup, 8.4±2.1%). This reduction in biopsy sensitivity related to mucosal thickening occurring adjacent to nonprotuberant lesions may explain, at least in part, the variable rates of positive biopsies observed with gastric cancers.Supported in part by a grant (AM07130) from the United States Public Health Service. 相似文献
92.
Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells 总被引:2,自引:1,他引:2
Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage- inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES). (2) Anti-Gi inhibited their migration in response to MCP-1 or RANTES but not in response to MIP-1 alpha. Second, incubation of IANK cell membranes with anti-G protein antibodies before incubating with (gamma-35S) GTP or (gamma-32P) GTP, resulted in the following. (1) Anti-G(s), anti-G(o), or anti-G(z) inhibited GTP binding and GTPase activity in the presence of MIP-1 alpha, or RANTES. (2) Anti- G(i) inhibited GTP binding and GTPase activity in the presence of MCP-1 or RANTES but not in the presence of MIP-1 alpha. The inhibitory effect of anti-G protein antibodies was reversed upon incubating these antibodies with their respective synthetic peptides before addition to IANK cell membranes. These results suggest that MCP-1 and RANTES receptors are promiscuously coupled to multiple G proteins in IANK cell membranes and that this coupling is different from MIP-1 alpha receptors, which seem to be coupled to G(s), G(o), and G(z) but not to G(i). 相似文献
93.
Cardoso AA; Schultze JL; Boussiotis VA; Freeman GJ; Seamon MJ; Laszlo S; Billet A; Sallan SE; Gribben JG; Nadler LM 《Blood》1996,88(1):41-48
Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance. 相似文献
94.
Francesco Vairo Emanuele Nicastri Salma Masauni Yussuf Angela Cannas Silvia Meschi Mwanakheir AA Mahmoud Azza H. Mohamed Paul Mohamed Maiko Pasquale De Nardo Nazario Bevilacqua Concetta Castilletti Antonino Di Caro Vincenzo Racalbuto Giuseppe Ippolito 《Emerging infectious diseases》2014,20(3):465-468
We conducted a seroprevalence survey among 500 healthy adult donors at Zanzibar National Blood Transfusion Services. Dengue virus IgG seroprevalence was 50.6% and independently associated with age and urban residence. These data will aid in building a surveillance, preparedness, and response plan for dengue virus infections in the Zanzibar Archipelago.Key words: dengue, seroprevalence, Zanzibar, viruses, vector-borne infections 相似文献
95.
96.
Mona Kamal El-Ghamrawy Hanan F. El Behairy Amal El Menshawy Seham A. Awad Ahmed Ismail Mohamed Salah Gabal 《Indian journal of hematology & blood transfusion》2014,30(4):275-280
In sickle cell disease (SCD), ocular lesions result from stasis and occlusion of small eye vessels by sickled erythrocytes. Vaso-occlusive disease of the retina can be responsible for nonproliferative (NPR) and proliferative retinopathy (PR). Patients are often asymptomatic until serious complications arise as, vitreous hemorrhage and retinal detachment. This work aimed to study the frequency and pattern of ocular manifestations in Egyptian children and young adults with SCD. In this cross-sectional study, 40 steady state patients (80 eyes) aged 2–28 years (30 children and 10 young adults) with established diagnosis of SCD (26 with homozygous SS and 14 with S/β thalassemia underwent complete ophthalmic examination with dilated fundoscopy. Fluorescein angiography was performed for patients ≥12 years old. The overall frequency of retinal lesions was 47.5 % (46.2 and 50 % of SS and S/β patients respectively). PR and NPR were evident in 32.5 and 27.5 % of all enrolled patients respectively (five patients having both). Peripheral retinal occlusion was a frequent ocular finding in both groups; the youngest patient showing PR was 15 years old. Older age, longer disease duration and splenectomy were significantly more prevalent among patients with PR. Despite lack of visual symptoms, children and young adults are at risk of PR. Frequency of retinal lesions was comparable in SS and S/β patients. Periodic ophthalmologic examination starting at the age of 12 years is recommended for timely-identification of retinal lesions thus minimizing the risk of sight threatening retinopathy. 相似文献
97.
Dalal M. Al-Taweel Abdelmoneim I. Awad B. Julienne Johnson 《International journal of diabetes in developing countries.》2014,34(2):108-115
This study was designed to identify pharmacists’ potential contributions to the delivery of pharmaceutical care to patients with type 2 diabetes in Kuwait, and to identify and explore barriers that were preventing them from providing care to this specific group. A pretested self-administered questionnaire was distributed to all pharmacists registered in the Kuwait Pharmaceutical Association’s email registry (N?=?250). Invitations to a focus group interview were then sent to all pharmacists (N?=?50) who had responded to the questionnaire. Seven pharmacists accepted the invitation and participated in the focus group interview. Of the 50 respondents to the questionnaire, 31 (62.0 %; 95 % CI: 47.2–75.4) indicated that they were “comfortable” and “extremely comfortable” in discussing patient’s blood pressure target and annual screening with physicians rather than discussing smoking cessation advice or specific medication-related care issues. More than 75 % of the respondents were “comfortable” and “extremely comfortable” in sharing and verifying the patient’s drug history, blood pressure, cholesterol and stability of blood glucose with the healthcare team, and to maintain a pharmaceutical care plan for patients with diabetes. Overall, pharmacists indicated that they were more comfortable in undertaking clinical activities than discussing care issues with physicians. The focus group interview identified issues related to pharmacist-physician interaction, pharmacists’ confidence, pharmacists’ image by patients and physicians and barriers to implementing pharmaceutical care. This study shows that pharmacists in Kuwait perceive that their contribution to the delivery of pharmaceutical care could develop further with increased partnership between pharmacists and physicians and provision of further education, training and continuing professional development support. 相似文献
98.
Sherif Awad Sharon Carter Sanjay Purkayastha Sherif Hakky Krishna Moorthy Jonathan Cousins Ahmed R. Ahmed 《Obesity surgery》2014,24(5):753-758
There is paucity of data on Enhanced Recovery After Bariatric Surgery (ERABS) protocols. This feasibility study reports outcomes of this protocol utilized within a tertiary-referral bariatric centre. Data on consecutive primary procedures (laparoscopic gastric bypasses, sleeve gastrectomies and gastric bands) performed over 9 months within an ERABS protocol were prospectively recorded. Interventions utilized included shortened preoperative fasts, intra-operative humidification, early mobilization and feeding, avoidance of fluid overload, incentive spirometry, use of prokinetics and laxatives. Data collected included demographics, co-morbidities, morbidity, mortality, length of stay (LOS) and re-admissions. A total of 226 procedures (age [mean ± SD], 45?±?11 years, median [interquartile range] BMI 44.9 [41.0–49.0] kg/m2) were undertaken: 150 (66 %) bypasses, 47 (21 %) sleeves and 29 (13 %) bands. Hypertension, diabetes mellitus, sleep apnea and limited mobility were present in 40 %, 34 %, 24 % and 9 % of patients, respectively. No anastomotic or staple line leaks/bleeds were encountered. Ten (4.4 %) patients developed postoperative morbidity (mainly respiratory complications). One death occurred from massive pulmonary embolus in a high-risk patient (despite insertion of preoperative-IVC filter). Respective mean ± SD LOS for bypasses, sleeves and bands were 1.88?±?1.12, 2.30?±?1.69 and 0.69?±?0.81 days. Successful discharge on the first postoperative day was achieved in 37 % and 28 % of bypasses and sleeves, respectively. Day-case gastric bands were performed in 48 %. Thirty-day hospital re-admission occurred in six (2.7 %) patients. Applying an ERABS protocol was feasible, safe, associated with low morbidity, acceptable LOS and low 30-day re-admission rates. The presence of multiple medical co-morbidities should not preclude use of an ERABS protocol within bariatric patients. 相似文献
99.
Ahmed M. Zihni Ikechukwu Ohu Jaime A. Cavallo Jenny Ousley Sohyung Cho Michael M. Awad 《Surgical endoscopy》2014,28(8):2459-2465
Introduction
Robotic surgery may result in ergonomic benefits to surgeons. In this pilot study, we utilize surface electromyography (sEMG) to describe a method for identifying ergonomic differences between laparoscopic and robotic platforms using validated Fundamentals of Laparoscopic Surgery (FLS) tasks. We hypothesize that FLS task performance on laparoscopic and robotic surgical platforms will produce significant differences in mean muscle activation, as quantified by sEMG.Methods
Six right-hand-dominant subjects with varying experience performed FLS peg transfer (PT), pattern cutting (PC), and intracorporeal suturing (IS) tasks on laparoscopic and robotic platforms. sEMG measurements were obtained from each subject’s bilateral bicep, tricep, deltoid, and trapezius muscles. EMG measurements were normalized to the maximum voluntary contraction (MVC) of each muscle of each subject. Subjects repeated each task three times per platform, and mean values used for pooled analysis. Average normalized muscle activation (%MVC) was calculated for each muscle group in all subjects for each FLS task. We compared mean %MVC values with paired t tests and considered differences with a p value less than 0.05 to be statistically significant.Results
Mean activation of right bicep (2.7 %MVC lap, 1.3 %MVC robotic, p = 0.019) and right deltoid muscles (2.4 %MVC lap, 1.0 %MVC robotic, p = 0.019) were significantly elevated during the laparoscopic compared to the robotic IS task. The mean activation of the right trapezius muscle was significantly elevated during robotic compared to the laparoscopic PT (1.6 %MVC lap, 3.5 %MVC robotic, p = 0.040) and PC (1.3 %MVC lap, 3.6 %MVC robotic, p = 0.0018) tasks.Conclusions
FLS tasks are validated, readily available instruments that are feasible for use in demonstrating ergonomic differences between surgical platforms. In this study, we used FLS tasks to compare mean muscle activation of four muscle groups during laparoscopic and robotic task performance. FLS tasks can serve as the basis for larger studies to further describe ergonomic differences between laparoscopic and robotic surgery. 相似文献100.
Enas Al-Zayadneh Nedal Awad Alnawaiseh Salma Ajarmeh Areej Hamed Altarawneh Eman M Albataineh Eyas AlZayadneh Alia Shatanawi Ebaa M Alzayadneh 《The Journal of international medical research》2020,48(12)
ObjectivesTo assess serum 25-hydroxycholecalciferol (25-OH vitamin D) levels in Jordanian children with bronchial asthma, and to examine correlations between 25-OH vitamin D levels and asthma severity and control.MethodsA cross-sectional study was conducted at the Paediatric Chest Clinic, Al-Karak Governmental Hospital, Southern Jordan, between May 2015 and February 2016. Serum 25-hydroxyvitamin D level was determined in children aged 1–14 years diagnosed with bronchial asthma (6–14 years) or recurrent wheezing episodes (<6 years). Asthma severity was determined based on the Global Initiative for Asthma assessment, the Asthma Control Test, and the Childhood Asthma Control Test. Demographic and clinical characteristics were compared between patients with low and normal 25-OH vitamin D levels, and correlations between asthma severity and 25-OH vitamin D level were assessed.ResultsOut of 98 included children, 25-OH vitamin D levels were deficient and insufficient in 41 (41.8%) and 34 (34.7%) children, respectively. Only 23 (23.5%) had sufficient 25-OH vitamin D levels. A significant correlation was found between severity of asthma symptoms and 25-OH vitamin D deficiency.Conclusion25-OH vitamin D deficiency is highly prevalent in Jordanian children with bronchial asthma and correlates significantly with asthma severity. 相似文献