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41.
Summary The immunological phenotypes of the lymphoid cells in 39 cutaneous malignant melanomas have been investigated by staining cryostat sections with a panel of 20 monoclonal antibodies against lymphoid cells and their subsets. Staining was performed by the alkaline phosphatase: anti-alkaline phosphatase (APAAP) method in which the substrate label (red) is easily distinguishable from melanin. The lymphoid infiltrates had an essentially identical composition in all cases, consisting of T-lymphocytes associated with both Langerhans cells and HLA-DR-positive tissue macrophages. B-lymphocytes and natural killer cells were either absent or only present in low numbers. The ratio between T8 (suppressor/cytotoxic) and T4 (helper/inducer) lymphocytes varied and showed no correlation with melanoma subtype, level of invasion or magnitude of lymphocytic response. Examination for markers associated with T-cell activation and/or with cell proliferation revealed that all lesions contained HLA-DR-positive T-lymphocytes, whereas expression of the transferrin receptor and the interleukin-2 receptor (Tac-antigen) occurred mainly in melanomas with a significant inflammatory infiltrate. These data support the concept that malignant melanomas are capable of evoking autologous T-cell immune reactions.  相似文献   
42.
It has long been recognized that intestinal blood flow increases at mealtimes. Mesenteric hyperaemia is also evoked by activation of sensory peptidergic nerves. Our studies explored the possible role of endogenous nitric oxide (NO) in the rat intestinal vasodilator response to luminal instillation of an oleic acid plus bile mixture before and after acute intrajejunal instillation of capsaicin and after chronic pretreatment with capsaicin. In anaesthetized rats we measured jejunal blood flow (BF) with an ultrasonic Doppler flowmeter and systemic arterial pressure (AP) with a pressure transducer. Intestinal perfusion with 80 mM oleic acid in bile increased BF by 98±12%. Instillation of 4 mg of capsaicin into the jejunal lumen initially increased BF by 42±9% but was followed by vasoconstriction. Inhibition of NO synthase with 25 mg/kg i.v. N-nitro-L-arginine (L-NNA) decreased BF by 27±5% and increased AP by 37±11%. After treatment with L-NNA and after acute and chronic administration of capsaicin, the bile-oleate-induced maximal increases in BF above control levels were 42±7%, 65±12%, and 58±8%, respectively. The observed inhibitory effect of L-NNA on the intestinal hyperaemic response to the bile-oleate mixture was reversed by pretreatment with L-arginine (100 mg/kg i.V.). In capsaicin pretreated rats the subsequent bile-oleate-induced hyperaemia was reduced in magnitude but the inhibitory effects of L-NNA were proportionately the same as in animals not receiving capsaicin. These findings support the hypothesis that NO is involved with bile-oleate-induced mesenteric hyperaemia.  相似文献   
43.
The activity of erythrocyte enzymes in rats subjected to running exercises   总被引:1,自引:0,他引:1  
Summary The studies were carried out on male Wistar rats subjected to running within an electric rotating drum. The animals were divided into four experimental groups, differing one from another as to the duration of training. Each training session lasted 30 days. In the first group the daily run lasted 3 min, in the second group 5 min; in the third group, a 1 min run on the first day, and one min longer on each successive day; in the fourth group a 2 min run on the first day and for two min longer on each successive day.The determinations made prior to and after training included the peripheral blood erythrocyte (Er) and reticulocyte (Ret.) count, the hemoglobin concentration (Hb) and packed cell volume (PCV) and, determined by spectrophotometric methods, the activity of pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G6PD) and glutathione reductase (GR). Training induced an improvement of all enzymatic activities. The heavier the physical exertion, the more intensive was the enzymatic activity of red blood cells, due to the intensification of bone marrow erythropoetic activity under physical exertion and the appearance of young red cells in peripheral blood. All the experimental groups revealed a drop in erythrocyte count (Er), hemoglobin concentration (Hb), and hematocrit values (PCV), as well as an increase in the reticulocytes count (Ret) and in the activity of all the enzymes investigated. In the fourth group anemia was detected: prolonged endurance training decreased the RBC by 24.2%, Hb by 31.1%, PCV by 26.2% and increased the reticulocyte count by 881.6%. Pronounced loading with physical effort leads to shifts in the glucose utilization ratio along particular erythrocyte metabolic pathways. This change in enzymatic activities may prove to be one of the causes of faster elimination of old RBCs.  相似文献   
44.
Malnutrition is a common problem in patients with head and neck cancer (HNC), including oropharyngeal cancer (OPC). It is caused by insufficient food intake due to dysphagia, odynophagia, and a lack of appetite caused by the tumor. It is also secondary to the oncological treatment of the basic disease, such as radiotherapy (RT) and chemoradiotherapy (CRT), as a consequence of mucositis with the dry mouth, loss of taste, and dysphagia. The severe dysphagia leads to a definitive total impossibility of eating through the mouth in 20–30% of patients. These patients usually require enteral nutritional support. Feeding tubes are a commonly used nutritional intervention during radiotherapy, most frequently percutaneous gastrostomy tube. Recently, a novel HPV-related type of OPC has been described. Patients with HPV-associated OPC are different from the HPV− ones. Typical HPV− OPC is associated with smoking and alcohol abuse. Patients with HPV+ OPC are younger and healthy (without comorbidities) at diagnosis compared to HPV− ones. Patients with OPC are at high nutritional risk, and therefore, they require nutritional support in order to improve the treatment results and quality of life. Some authors noted the high incidence of critical weight loss (CWL) in patients with HPV-related OPC. Other authors have observed the increased acute toxicities during oncological treatment in HPV+ OPC patients compared to HPV− ones. The aim of this paper is to review and discuss the indications for nutritional support and the kinds of nutrition, including immunonutrition (IN), in HNC, particularly OPC patients, undergoing RT/CRT, considering HPV status.  相似文献   
45.
BackgroundThe aim of this study was to assess the analgesic efficacy of sufentanil in dressings after surgical treatment of burn wounds.Patients and methodsTwenty adult patients, who underwent surgical treatment of third–degree burn wounds under general anesthesia, were included. Two of the patients underwent surgery twice. During surgery, patients received 50–100 μg fentanyl every 20–30 min and, after surgery, patients received 100 mg ketoprofen twice daily. Additionally, ten patients (group 1) received 50 μg sufentanil added to the burn wound dressings soaked in octenidine and phenoxyethanol while 10 patients (group 2) received 25 μg sufentanil added to the same dressings. The rescue analgesic, which was administered when pain intensified, was 5 mg subcutaneous morphine. Plasma sufentanil concentrations were assayed at 1, 2, 3, and 6 h after surgery completion and when pain was reported, along with pain intensity evaluation.ResultsSufentanil was not detected in the serum of any patients. Rescue morphine was given during the postoperative period (24 h) in one patient in group 1 (who underwent surgery twice) and three patients in group 2. The mean sufentanil concentration in dressings was higher in group 1 (0.13 ± 0.03) than group 2 (0.06 ± 0.03 μg/mL; p < 0.001). The group 1 patient who received rescue morphine had a sufentanil concentration of 0.10 μg/mL, which was the lowest concentration in group 1. Group 2 patients who received rescue morphine had sufentanil concentrations of at least two–fold lower (0.03–0.05 μg/mL). No adverse effects were observed.ConclusionsSufentanil in dressings after burn wound surgery provides effective and safe analgesia and the sufentanil concentration in dressings should be ≥0.10 μg/mL in a solution of octenidine and phenoxyethanol.  相似文献   
46.
BackgroundArteriovenous fistulae (AVFs) may remain patent after kidney transplantation (KTx), contributing to maladaptive cardiac remodeling. The flow in AVFs is associated with the diameter of its vessels and thus with the AVF location. The main objective of this study is to assess the influence of AVF location and its patency on the self-reported quality of life (QOL) of kidney transplant recipients (KTRs) with past history of hemodialysis.MethodsTo gain clinical data, during a scheduled visit, 353 KTRs were asked to fill out an anonymous questionnaire. From this group, 284 respondents were found eligible for analysis. The outcome was defined as prevalence of symptoms and health status, measured with the Left Ventricular Dysfunction-36 (LVD-36) Questionnaire in symptomatic patients.ResultsThe hemodialysis patients (n = 243) were divided into two groups according to AVF location, i.e., DAVF – distally located AVF – (n = 174) and PAVF – proximally located AVF – (n = 69). The proportion of patients with heart failure (HF) was higher in PAVF group (24% vs. 12%, p = 0.0482). In the multivariable regression, PAVF, serum creatinine levels, and the presence of HF or coronary artery disease (CAD) remained independent predictors of lower functional capacity. Among patients with heart disease, the presence of active AVF was independently associated with worse functional outcome (higher LVD-36 scores).ConclusionsThe influence of persistent PAVF in KTRs seems to be unfavorable, especially when coexisting with CAD or HF. Abbreviations: AVF arteriovenous fistula; BMI body mass index; CAD coronary artery disease; D-AVF distally-located arteriovenous fistula; EC exercise capacity; HD hemodialysis; HF heart failure; KTx kidney transplantation; KTR kidney transplant recipient; LVD-36 Left Ventricle Disfunction – 36; LVEF left ventricle ejection fraction; LVH left ventricle hypertrophy; NYHA New York Heart Association; P-AVF proximally located arteriovenous fistula; PD peritoneal dialysis; PRO patient-reported outcomes; QOL quality of life.  相似文献   
47.
ObjectivesT-cell-mediated adaptive immunity contributes to the development and persistence of ankylosing spondylitis (AS). Mesenchymal stromal/stem cells (MSCs) have immunomodulatory potential and are able to inhibit T-cell proliferation, but their functionality in AS patients is relatively unknown. The aim of the study was to assess the direct anti-proliferative effects of MSCs isolated from subcutaneous abdominal adipose tissue of AS patients (AS/ASCs) on allogeneic T lymphocytes, using commercially available ASC lines from healthy donors (HD/ASCs) as a control.Material and methodsCD3+CD4+ T-cells were isolated from peripheral blood of healthy blood donors, activated with anti-CD3/CD28 beads, and co-cultured for 5 days with untreated and TNF+IFN-γ pre-stimulated HD/ASCs (5 cell lines) and AS/ASCs, obtained from 11 patients (6F/5M). The proliferative response of T-cells was analysed by flow cytometry, while the concentrations of kynurenines, prostaglandin E2 (PGE-2), interleukin 10 (IL-10), and interleukin 1 receptor antagonist (IL-1Ra) were measured spectrophotometrically or using a specific enzyme-linked immunosorbent assay (ELISA).ResultsHD/ASCs and AS/ASCs similarly reduced the T-cell proliferation response, i.e. the percentage of proliferating cells, the proliferation, and replication indices, and these effects were dependent mostly on soluble factors. In the co-cultures of activated CD4+ T-cells with HD/ASCs and AS/ASCs significant increases of kynurenines, PGE-2, and IL-1Ra, but not IL-10, production were observed. The release of these factors was dependent either on cell-to-cell contact (IL-10, IL-1Ra) or soluble factors (kynurenines, PGE-2). There was a moderate to strong negative correlation between T-cell proliferative response, and the concentrations of kynurenines, PGE-2, and IL-10, but not IL-1Ra. This association was more evident in the case of TI-treated AS/ASCs than HD/ASCs.ConclusionsAS/ASCs, similar to HD/ASCs, exert a direct effective anti-proliferative impact on CD4+ T cells, acting via soluble factors that are released in cell contact-dependent (IL-10) and independent (kynurenines, PGE-2) pathways. Thus, our results suggest that AS/ASCs are potentially useful for therapeutic application.  相似文献   
48.
The effect of butylated hydroxyanisole (BHA) administrationon the hepatic monooxygenase system of nuclear and microsomalfraction was investigated in male mice. Addition of BHA to thediet significantly lowered the content of cytochrome P-450 inliver nuclei and increased the specific activity of NADPH-cytochromec reductase and the content of cytochrome b5 in liver microsomes.Incubation of benzo[a]pyrene (BP) with liver nuclei from BHA-fedmice resulted in inhibition of binding of BP metabolites tonuclear macromolecules by 50% compared with control. However,there was no effect of BHA on the binding of BP metabolitesto macromolecules when BP was incubated with added DNA and livermicrosomes from BHA-fed mice. It has been postulated that modificationof nuclear monooxygenases by BHA may play a role in the inhibitoryeffect of BHA on BP carcinogenesis.  相似文献   
49.
Gastric cancer is the second most frequently diagnosed malignancy worldwide and therefore represents a significant healthcare burden. Environmental and genetic factors are involved in the development of gastric cancer. To date only one clear genetic predisposition has been identified involving mutations in the E-cadherin gene. The disease phenotype in patients harbouring E-cadherin mutations appears to be specifically related to diffuse gastric cancer. Little is known genetically about the other forms of gastric cancer. Since there is a growing awareness about the necessity of early intervention criteria have been developed that aid the identification of hereditary forms of gastric cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be provided with risk assessment and/or genetic testing.The results reveal that inclusion features described herein such as (a) gastric cancer diagnosed before 46 years of age; (b) two gastric cancers among first degree relatives diagnosed over the age of 50 are useful in identifying suspected hereditary gastric cancer patients.  相似文献   
50.
The aim of the study was to use the appraisal model of stress to compare hemodialysis (HD) and continuous peritoneal dialysis (CAPD) patients with special focus on the perception of end-stage renal disease and subsequent emotional profile and health related quality of life (HQoL) in. We hypothesize that different circumstances related to both modes of therapies will result in dissimilar perception of chronic illness with subsequent changes in emotional profile and heath related quality of life. The total of 88 patients with end stage renal disease (ESRD) enrolled in hemodialysis (n=52; HD) or continuous peritoneal dialysis (n=36; CAPD) were given a battery of psychological tests: The Profile of Mood States, The Nottingham Health Profile, The Stress Situation Assessment Questionnaire, The Social Appreciation Questionnaire and The Situation and Trait and Anxiety Inventory. All patients perceived ESRD in terms of a loss and a threat. Moreover, CAPD patients evaluated ESRD as a challenge. Despite different perception of ESRD no significant difference in the level of fear, anxiety or emotional profile was found. Both HD and CAPD patient were reported more fatigue/inertia and confusion/bewilderment than control groups. The main health related complaints were similar in both ESRD patients with major complaints of sleeping disturbances, motor limitations and lack of energy. From the psychological point of view, CAPD treatment seems more like challenge to the enrolled patient which is positive outcome. Despite different appraisal of stress mood and health related complaints were similar in both groups. This may be a result of optimal regulation of cognitive perception of the stress depending on the circumstances of therapy.  相似文献   
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