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1.
Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献2.
BACKGROUND: The 1997 National Asthma Education and Prevention Program (NAEPP) recommends a severity classification scheme to optimize the use of anti-inflammatory therapy for persistent asthma. Physician documentation of asthma severity is often used as a quality assurance measure. OBJECTIVE: To test the hypothesis that physician documentation of asthma severity is associated with appropriate use of anti-inflammatory therapy. DESIGN/METHODS: Setting: inner-city academic health center. First, we reviewed a consecutive sample of charts of scheduled pediatric patients. Then, we administered a structured parent survey regarding the child's asthma symptoms and current asthma therapy. We used NAEPP guidelines to classify patients' severity of asthma. The main outcome measure was appropriate use of anti-inflammatory therapy. Appropriate therapy was defined as: (1) mild persistent asthmatics using anti-inflammatory therapy, and (2) moderate-severe persistent asthmatics using inhaled steroids. Chart classification of asthma severity was compared with the NAEPP-applied classification. RESULTS: Of 784 charts, 214 (27%) were asthmatic. Of these, 176 (82%) were surveyed. The mean age was 7.4 years; 61% were males. Severity classification was documented in 77% of charts. Chart documentation differed significantly from survey classification for the same patients: (mild intermittent 54% vs. 40%, mild persistent 21% vs. 14%, moderate persistent 24% vs. 36%, severe persistent 1% vs. 10%; all p < .001). Correctly classified patients were more likely to be on appropriate therapy. CONCLUSIONS: Physicians underestimated the severity classification of asthmatic patients. Incorrect classification was associated with inappropriate asthma therapy. These findings have implications for the institution of asthma quality improvement programs. 相似文献
3.
Pilomatrixoma are neoplasms of the hair cortical cells. They are most common during the first two decades of life and, usually, involve the head, neck, and upper extremities. These tumors may be encountered during aspiration biopsy of subcutaneous masses, and are, occasionally, confused with other neoplasms, particularly squamous cell carcinomas and epidermal inclusion cysts. The cytologic features of three such neoplasms are presented, and the characteristics that differentiate them from other benign and malignant lesions of the skin are discussed. The presence of two cell populations, the anucleated shadow cells and the basaloid cells, which lack nuclear features of malignancy, is fairly specific for pilomatrixoma. In addition, the specimens obtained from aspiration may be misinterpreted as originating from a hyperplastic lymph node in view of the intense chronic inflammatory and foreign body reaction seen in the background. Calcific deposits that lack lamellations, unlike psammoma bodies, help in establishing the definitive diagnosis of these benign neoplasms. 相似文献
4.
Maite Sainz De La Maza Ramzy K. Hemady C. Stephen Foster 《Documenta ophthalmologica. Advances in ophthalmology》1993,83(1):33-41
While systemic autoimmune diseases are the main possibilities in the differential diagnosis of scleritis, other less common etiologies such as infections must also be considered. The authors report four cases of infectious scleritis to review predisposing factors, clinical characteristics, methods of diagnostic approach, and response to therapy. Two patients had primary scleritis and two patients had secondary scleritis following extension of primary corneal infection (corneoscleritis). Diagnoses included three local infections (one each withStaphylococcus. Acanthamoeba, and herpes simplex) and one systemic infection (Lyme disease). Stains, cultures, or immunologic studies from scleral, conjunctival, and/or corneal tissues, and serologic tests were used to make the diagnosis. Medical therapy, including antimicrobial agents, was instituted in all patients, and surgical procedures were additionally required in two patients (scleral grafting in one and two penetrating keratoplasties in another); the patient who required two penetrating keratoplasties had corneoscleritis and underwent eventual enucleation. Infectious agents should be considered in the differential diagnosis of scleritis. 相似文献
5.
Shunichi Takaya MD Shunzaburo Iwatsuki Takashi Noguchi Hisaaki Koie Iman Zaghloul Raman Venkataramanan Thomas E. Starzl 《Surgery today》1989,19(1):49-56
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined
in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy
or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin,
and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of
CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax
decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy.
At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration
curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL
also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6
per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent
and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment
significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those
in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain
an adequate blood concentration of CsA without causing side effects.
This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh,
USA 相似文献
6.
Kemal Yucesoy Iman Feiz-Erfan Robert F. Spetzler Patrick P. Han Stephen Coons 《Skull base》2004,14(3):169-173
A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment. 相似文献
7.
8.
Iman Al‐Saleh Andrew Taylor Richard Hinton 《International journal of environmental health research》1992,2(4):184-191
Erythrocyte protoporphyrin and blood lead concentrations were measured in samples from 583 Saudi children attending the outpatient clinics. Erythrocyte protoporphyrin concentrations showed poor correlation with blood lead concentrations of 25 ug dl?1 and below. Measurement of erythrocyte protoporphyrin as a primary test for lead exposure is not recommended. 相似文献
9.
10.
Genome-scale reconstruction of the Saccharomyces cerevisiae metabolic network 总被引:9,自引:0,他引:9 下载免费PDF全文
The metabolic network in the yeast Saccharomyces cerevisiae was reconstructed using currently available genomic, biochemical, and physiological information. The metabolic reactions were compartmentalized between the cytosol and the mitochondria, and transport steps between the compartments and the environment were included. A total of 708 structural open reading frames (ORFs) were accounted for in the reconstructed network, corresponding to 1035 metabolic reactions. Further, 140 reactions were included on the basis of biochemical evidence resulting in a genome-scale reconstructed metabolic network containing 1175 metabolic reactions and 584 metabolites. The number of gene functions included in the reconstructed network corresponds to approximately 16% of all characterized ORFs in S. cerevisiae. Using the reconstructed network, the metabolic capabilities of S. cerevisiae were calculated and compared with Escherichia coli. The reconstructed metabolic network is the first comprehensive network for a eukaryotic organism, and it may be used as the basis for in silico analysis of phenotypic functions. 相似文献