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51.
V. A. Arankalle J. Jha M. O. Favorov A. Chaudhari H. A. Fields K. Banerjee 《Journal of viral hepatitis》1995,2(4):189-193
Summary. During 1990, 38 patients with fulminant non-A, non-B hepatitis (NANB) died in Government Medical College Hospital, Aurangabad. Serum samples from these patients were tested for antibodies to hepatitis C virus (anti-HCV) and IgM antibodies to hepatitis E virus (IgM-anti-HEV). All samples were also subjected to polymerase chain reaction (PCR) for the detection of HBV DNA, HCV RNA and HEV RNA. None of the patients had circulating anti-HCV antibodies; three had HCV RNA. Based on anti-HEV-IgM positivity 14 patients (37%) could be diagnosed as suffering from hepatitis E. None was positive for HEV RNA. In the absence of serological markers, HBV DNA was present in three cases. None of the HBV DNA positive patients had anti-δ antibodies. Dual infections (HBV with HEV, and HBV with HCV) were seen in two cases. The aetiology of half of the NANB cases could not be assigned to the known hepatitis viruses using current techniques. 相似文献
52.
Jeremy Z. Fields Mark Jacyno Roxana Wasyliw Daniel Winship Ali Keshavarzian 《Alcoholism, clinical and experimental research》1995,19(6):1403-1413
Acute ethanol (EtOH) in vivo decreases both the pressure of the lower esophageal sphincter (LES) and the amplitude of contractions of the smooth muscle of the lower esophageal body (LEB) in both man and cat. However, the mechanism of this inhibitory effect of EtOH is unclear. This inhibitory effect could be caused by a direct effect of EtOH on the esophagus or be secondary to known inhibitory effects of EtOH on the central nervous system. To this end, we evaluated the in vitro effect of EtOH on contractility of smooth muscle strips from both LES and LEB. Circular muscle strips from LES and LEB were isolated from cats. Changes in resting tension of LES strips and changes in stimulant-induced tension of LES or LEB strips were measured in the presence of up to five concentrations of EtOH (12.5–100 mM). Stimulants included electric field stimulation (EFS) and carbachol. EtOH at 75 mM significantly decreased resting LES tension. EtOH also decreased maximal contractile responses to carbachol in both LES and LEB and increased the EC50 of carbachol for LES, but not LEB. EtOH also modulated EFS-induced esophageal contractility; EtOH potentiated EFS-induced "on-response relaxation" in LES and decreased EFS-induced "off-response contractions" in LEB. EtOH-induced inhibition of esophageal contractility seemed to be reversible. EtOH did not result in muscle fatigue. Thus, EtOH can directly inhibit contractility of the esophagus, and does so reversibly and at pharmacologically relevant concentrations. 相似文献
53.
Loop Ileostomy Closure at an Ambulatory Surgery Facility 总被引:1,自引:0,他引:1
Kalady MF Fields RC Klein S Nielsen KC Mantyh CR Ludwig KA Nielson KC 《Diseases of the colon and rectum》2003,46(4):486-490
INTRODUCTION: Temporary loop ileostomies have become widely used in colorectal surgery. Subsequent ileostomy closure has traditionally required hospital admission with observation until return of bowel function. On the basis of clinical observation, the authors hypothesized that loop ileostomy closure may be performed safely without prolonged in-hospital observation.
METHODS: A protocol for 23-hour observation after loop ileostomy closure was implemented at a single institution and applied to 28 patients at an ambulatory surgery facility. Patient outcomes were reviewed and results compared with a cohort of 30 patients undergoing loop ileostomy closure before introduction of the protocol.
RESULTS: The study and control groups were statistically similar in age, gender, diseases, and duration after original operation. Twenty-eight patients underwent loop ileostomy closure, and all were discharged the following day. Two patients were admitted for nausea and vomiting within 48 hours after closure and remained in the hospital for two and four days, respectively. One of these patients was readmitted 12 days after surgery with an abdominal abscess that was drained percutaneously. The mean cost per patient in the study group was $2,665. For the control population, the mean hospital stay was 2.9 days. Return of bowel function was delayed in two patients, resulting in prolonged hospital stays of six and eight days, respectively. Two patients were readmitted after discharge for nausea and vomiting. The mean cost per cohort patient was $3,811.
CONCLUSIONS: Patients undergoing loop ileostomy closure may be discharged safely after overnight observation without increased complications or hospital readmissions. This practice significantly reduces the use of hospital resources and decreases economic cost without compromising care. 相似文献
54.
Alterations in intervertebral disc composition,matrix homeostasis and biomechanical behavior in the UCD‐T2DM rat model of type 2 diabetes 下载免费PDF全文
Aaron J. Fields Britta Berg‐Johansen Lionel N. Metz Stephanie Miller Brandan La Ellen C. Liebenberg Dezba G. Coughlin James L. Graham Kimber L. Stanhope Peter J. Havel Jeffrey C. Lotz 《Journal of orthopaedic research》2015,33(5):738-746
Type 2 diabetes (T2D) adversely affects many tissues, and the greater incidence of discogenic low back pain among diabetic patients suggests that the intervertebral disc is affected too. Using a rat model of polygenic obese T2D, we demonstrate that diabetes compromises several aspects of disc composition, matrix homeostasis, and biomechanical behavior. Coccygeal motion segments were harvested from 6‐month‐old lean Sprague‐Dawley rats, obese Sprague‐Dawley rats, and diabetic obese UCD‐T2DM rats (diabetic for 69 ± 7 days). Findings indicated that diabetes but not obesity reduced disc glycosaminoglycan and water contents, and these degenerative changes correlated with increased vertebral endplate thickness and decreased endplate porosity, and with higher levels of the advanced glycation end‐product (AGE) pentosidine. Consistent with their diminished glycosaminoglycan and water contents and their higher AGE levels, discs from diabetic rats were stiffer and exhibited less creep when compressed. At the matrix level, elevated expression of hypoxia‐inducible genes and catabolic markers in the discs from diabetic rats coincided with increased oxidative stress and greater interactions between AGEs and one of their receptors (RAGE). Taken together, these findings indicate that endplate sclerosis, increased oxidative stress, and AGE/RAGE‐mediated interactions could be important factors for explaining the greater incidence of disc pathology in T2D. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:738–746, 2015. 相似文献
55.
Defining the domains of type I collagen involved in heparin- binding and endothelial tube formation 总被引:2,自引:0,他引:2
Shawn M. Sweeney Cynthia A. Guy Gregg B. Fields James D. San Antonio 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(13):7275-7280
Cell surface heparan sulfate proteoglycan (HSPG) interactions with type I collagen may be a ubiquitous cell adhesion mechanism. However, the HSPG binding sites on type I collagen are unknown. Previously we mapped heparin binding to the vicinity of the type I collagen N terminus by electron microscopy. The present study has identified type I collagen sequences used for heparin binding and endothelial cell–collagen interactions. Using affinity coelectrophoresis, we found heparin to bind as follows: to type I collagen with high affinity (Kd ≈ 150 nM); triple-helical peptides (THPs) including the basic N-terminal sequence α1(I)87–92, KGHRGF, with intermediate affinities (Kd ≈ 2 μM); and THPs including other collagenous sequences, or single-stranded sequences, negligibly (Kd 10 μM). Thus, heparin–type I collagen binding likely relies on an N-terminal basic triple-helical domain represented once within each monomer, and at multiple sites within fibrils. We next defined the features of type I collagen necessary for angiogenesis in a system in which type I collagen and heparin rapidly induce endothelial tube formation in vitro. When peptides, denatured or monomeric type I collagen, or type V collagen was substituted for type I collagen, no tubes formed. However, when peptides and type I collagen were tested together, only the most heparin-avid THPs inhibited tube formation, likely by influencing cell interactions with collagen–heparin complexes. Thus, induction of endothelial tube morphogenesis by type I collagen may depend upon its triple-helical and fibrillar conformations and on the N-terminal heparin-binding site identified here. 相似文献
56.
Systemic administration of interleukin 2 enhances the therapeutic efficacy of dendritic cell-based tumor vaccines 总被引:15,自引:0,他引:15 下载免费PDF全文
Shimizu K Fields RC Giedlin M Mulé JJ 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(5):2268-2273
We have reported previously that murine bone marrow-derived dendritic cells (DC) pulsed with whole tumor lysates can mediate potent antitumor immune responses both in vitro and in vivo. Because successful therapy was dependent on host immune T cells, we have now evaluated whether the systemic administration of the T cell stimulatory/growth promoting cytokine interleukin-2 (IL-2) could enhance tumor lysate-pulsed DC-based immunizations to further promote protective immunity toward, and therapeutic rejection of, syngeneic murine tumors. In three separate approaches using a weakly immunogenic sarcoma (MCA-207), the systemic administration of nontoxic doses of recombinant IL-2 (20,000 and 40,000 IU/dose) was capable of mediating significant increases in the potency of DC-based immunizations. IL-2 could augment the efficacy of tumor lysate-pulsed DC to induce protective immunity to lethal tumor challenge as well as enhance splenic cytotoxic T lymphocyte activity and interferon-gamma production in these treated mice. Moreover, treatment with the combination of tumor lysate-pulsed DC and IL-2 could also mediate regressions of established pulmonary 3-day micrometastases and 7-day macrometastases as well as established 14- and 28-day s.c. tumors, leading to either significant cure rates or prolongation in overall survival. Collectively, these findings show that nontoxic doses of recombinant IL-2 can potentiate the antitumor effects of tumor lysate-pulsed DC in vivo and provide preclinical rationale for the use of IL-2 in DC-based vaccine strategies in patients with advanced cancer. 相似文献
57.
Trevor R. Banka Allison Ruel Kara Fields Jacques YaDeau Geoffrey Westrich 《HSS journal》2015,11(1):71-75
Background
Little is known about preoperative predictors of postoperative pain and referral to a recuperative pain management service after total knee arthroplasty (TKA).Questions/Purposes
We sought to identify the preoperative predictors of postoperative pain scores, referral to a pain management service, and narcotic usage in patients undergoing primary total knee arthroplasty.Methods
We performed a prospective cohort study of 97 TKAs from a single surgeon. Pre and 6-week postoperative WOMAC, visual analog pain scale (VAS) scores, narcotic usage, and catastrophizing pain scores were collected.Results
After adjusting for all other variables, higher age and catastrophizing pain scores were associated with lower odds of postoperative opioid usage. Increasing age and BMI were associated with lower odds of being referred to pain management. There was no relationship between self-reported preoperative pain tolerance and postoperative change in WOMAC or VAS pain scores.Conclusions
This information may help surgeons advise their patients preoperatively and set expectations during the recovery period.Electronic supplementary material
The online version of this article (doi:10.1007/s11420-014-9418-4) contains supplementary material, which is available to authorized users. 相似文献58.
AA Aksyuk VD Bowman B Kaufmann C Fields T Klose HA Holdaway VA Fischetti MG Rossmann 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(35):14001-14006
The Podoviridae phage C1 was one of the earliest isolated bacteriophages and the first virus documented to be active against streptococci. The icosahedral and asymmetric reconstructions of the virus were calculated using cryo-electron microscopy. The capsid protein has an HK97 fold arranged into a T = 4 icosahedral lattice. The C1 tail is terminated with a φ29-like knob, surrounded by a skirt of twelve long appendages with novel morphology. Several C1 structural proteins have been identified, including a candidate for an appendage. The crystal structure of the knob has an N-terminal domain with a fold observed previously in tube forming proteins of Siphoviridae and Myoviridae phages. The structure of C1 suggests the mechanisms by which the virus digests the cell wall and ejects its genome. Although there is little sequence similarity to other phages, conservation of the structural proteins demonstrates a common origin of the head and tail, but more recent evolution of the appendages. 相似文献
59.
We report a patient with chest pain who was classified as having low risk for pulmonary embolism with clinical gestalt and accepted clinical decision rules. An inadvertently ordered D-dimer and abnormal result, however, led to the identification of a large saddle embolus. This case illustrates the fallibility of even well-validated decision aids and that an embolism missed by these tools is not necessarily low risk or indicative of a low clot burden. 相似文献
60.
Adam L Boxer David S Knopman Daniel I Kaufer Murray Grossman Chiadi Onyike Neill Graf-Radford Mario Mendez Diana Kerwin Alan Lerner Chuang-Kuo Wu Mary Koestler Jill Shapira Kathryn Sullivan Kristen Klepac Kristine Lipowski Jerin Ullah Scott Fields Joel H Kramer Bruce L Miller 《Lancet neurology》2013,12(2):149-156