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1.
BACKGROUND: Usually, atrophic body gastritis has been considered an autoimmune disease characterized by the presence of parietal cell antibodies. Previous investigations into the role of Helicobacter pylori infection have obtained conflicting results. The aim of this study was to investigate the prevalence and role of H. pylori in a prospectively investigated population of patients with corpus-predominant atrophic gastritis. PATIENTS AND METHODS: A consecutive series of 67 newly diagnosed cases of atrophic body gastritis was derived from a screening of 326 patients with unexplained anemia or dyspepsia. Criteria for diagnosis were fasting hypergastrinemia, pentagastrin-resistant achlorhydria, and histological confirmation of body atrophy. In all 67 patients, H. pylori infection was evaluated independently by histological assay and urease test. The gastritis status of both the fundic and antral mucosa were graded according to the Sydney system. Parietal cell and intrinsic factor antibodies also were determined. RESULTS: Active H. pylori infection was present in 26.8% of our patients and allowed us to identify a patient's subpopulation with a significantly smaller degree of body mucosa damage as shown by functional parameters (gastrin, gastric acid secretion, pepsinogen I) and histological assessment. In this subpopulation, a higher prevalence of gastric cancer familial history was found. Presence of parietal cell antibodies showed a similar prevalence in H. pylori-positive and H. pylori-negative patients (61.1% vs. 69.4%) and was not associated with significant functional and histological differences. Cure of infection determined an evident improvement of corporal atrophy as well as a reduction of hypergastrinemia. CONCLUSION: Active H. pylori infection, a potential cause of oxyntic gland atrophy, is found in one-fourth of patients with newly diagnosed atrophic body gastritis.  相似文献   

2.
Vascular occlusion and vasculopathy underlie much of the morbidity in patients with sickle cell anaemia. Platelets may play a role in this vasculopathy. Samples from 43 patients with sickle cell disease (SCD) were examined for evidence of platelet activation using fluorescent-labelled monoclonal antibodies and flow cytometry. There was increased expression of activation-dependent antigens on the platelets from patients with SCD compared to those from both Caucasian and African-American controls. In addition, SCD patients had increased levels of platelet microparticles. Platelets are activated in patients with sickle cell disease. The contribution of platelet activation to sickle cell pathophysiology is under active investigation in our laboratories.  相似文献   

3.
The possible activation of monocytes to express tissue factor procoagulant activity (TF-PCA) during CPB (cardiopulmonary bypass) was investigated. 22 patients undergoing myocardial revascularization were randomly assigned to two groups. In group C, heparin-coated circuits (Duraflo II) and reduced systemic heparinization (ACT > 250s) were used. In group NC, non-coated circuits and standard heparin administration (ACT > 480s) were used. Adherent monocytes retrieved from the oxygenators immediately after bypass arrest showed a 2-3-fold increase in TF-PCA when compared to circulating cells pre-CPB (P < 0.01). When cell PCA was expressed as percent change from pre-CPB (baseline) values, circulating monocytes in group NC at CPB-arrest showed a 2-fold increase in PCA compared to group C (P < 0.05). Moreover, the percent increase in PCA of oxygenator-retrieved monocytes was 7-fold in group NC and 2-fold in group C (P < 0.008 and P < 0.004, respectively). Thus, heparin-coating of the extracorporeal circuit reduced induction of adherent cell TF-PCA by 70% (P < 0.05). Thus, monocyte TF-PCA may cause activation of the extrinsic coagulation pathway during CPB surgery. It is apparent that heparin-coating enhanced biocompatibility of extracorporeal circuits. Reduced systemic heparinization in group C proved to be safe. However, further reduction of heparin administration may not be advisable, since monocytes were still activated in the coated oxygenator.  相似文献   

4.
Protein C levels were determined in 40 Gabonese children with sickle cell disease, in the steady state and during vasoocclusive crisis. In comparison with 40 healthy controls matched for age and sex, there was a significant decrease in protein C activity in the patients, although no difference was found between protein C levels in the steady state and during crisis.  相似文献   

5.
OBJECTIVE: Our purpose was to determine whether red blood cells from patients with severe preeclampsia may exhibit increased membrane exposure of procoagulant phospholipids (i.e., phosphatidylserine), which may initiate intravascular clotting and platelet activation. STUDY DESIGN: The study group comprised 28 women: 9 with severe preeclampsia in the third trimester of pregnancy, 10 normotensive with uncomplicated pregnancies, and 9 age-matched, nonpregnant, healthy women. The exposure of phosphatidylserine on the outer membrane phospholipid layer was analyzed with use of isolated, washed red blood cells that were added as a source of phospholipids to a "prothrombinase" coagulation complex. RESULTS: The resultant thrombin formed was measured by an amidolytic assay. Thrombin generation significantly increased on the addition of red blood cells from women with preeclampsia (741 +/- 132 mU/ml/min) compared with red blood cells from normotensive pregnant (422 +/- 228 mU/ml/min) and nonpregnant women (316 +/- 268 mU/ml/min, p = 0.0008). CONCLUSION: This study indicates that in patients with preeclampsia the red blood cells exhibit a significant procoagulant surface that may trigger thrombin formation, thereby playing a role in the hypercoagulable state.  相似文献   

6.
We investigated the effects of hypoxia on red blood cell (RBC)-endothelial cell (EC) adherence and the potential mechanism(s) involved in mediating this effect. We report that hypoxia significantly increased sickle RBC adherence to aortic EC when compared with the normoxia controls. However, hypoxia had no effect on the adherence of normal RBCs. In additional studies, we found that the least dense sickle RBCs containing CD36+ and VLA-4+ reticulocytes were involved in hypoxia-induced adherence. We next evaluated the effects of hypoxia on the expression of EC surface receptors involved in RBC adherence to macrovascular ECs, including vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), and the vitronectin receptor (VnR). Hypoxia upregulated the expression of both VCAM-1 and ICAM-1, whereas no effect on VnR was noted. Potential involvement of VCAM-1 and ICAM-1 in mediating hypoxia-induced sickle RBC-EC adhesion was next investigated using monoclonal antibodies against these receptors. Whereas anti-VCAM-1 had no effect on basal adherence, it inhibited hypoxia-induced sickle RBC adherence in a concentration-dependent manner, with 50% to 75% inhibition noted at 10 to 60 micrograms/mL antibody (n = 6, P < .05 to P < .01). Anti-ICAM-1 (10 to 60 micrograms/mL, n = 8) had no effect on either basal or hypoxia-induced adherence. As noted in the bovine aortic ECs, hypoxia stimulated the adherence of sickle RBCs to human retinal capillary ECs, and this response appeared to be mediated via mechanisms similar to those observed with macro-endothelium, ie, via the adhesive receptor combination VCAM-1-VLA-4. Our studies show that hypoxia enhances sickle RBC adhesion to both macrovascular and human microvascular ECs via the adhesive receptor VCAM-1. Our findings are of interest because hypoxia is an integral part of the pathophysiology of the vaso-occlusive phenomenon in sickle cell anemia.  相似文献   

7.
This paper describes a cost-effective technique that optimally utilizes all available diagnostic studies for three-dimensional treatment planning. A simulator unit modified to produce cross-sectional images (simulator-CT unit) is used to create a reference data set with the patient in the treatment position. Registration software (qsh) brings other diagnostic studies into agreement with this reference data set. Two cases are presented as examples of the use of this technique. Registration of abdominal scans from the same patient demonstrates the warping of a nontreatment position study to the treatment position. The second case is based on paired data sets through the head, in which the diagnostic study was obtained by using a gantry tilt to follow the base of the skull and to avoid sections passing through the teeth. The registration software provides a method for combining diagnostic studies into a single "master" data set. The success of the transformation depends on the operator's ability to identify corresponding anatomic landmarks for different data sets and on the magnitude of the variation in the patient's position from one procedure to the next. Limitations in image quality and the number of cross-sections obtainable from a simulator-CT unit can be partially overcome by using the described technique. Thus, the information contained in nontreatment position diagnostic tests can be used accurately for treatment planning at limited cost.  相似文献   

8.
9.
目的:探讨社区老年高血压患者危险因素状况及干预情况.方法:调查社区400名老年人,患高血压病148例(37.0%),统计合并高脂血症、肥胖、吸烟、糖尿病、缺乏体力活动、早发心血管病家族史以及冠心病、卒中或短暂性脑缺血发作的比例.结果:老年高血压患者合并其他心血管危险因素的比例较高,尤以高盐饮食(55.4%)和高脂血症(54.1%)最明显,且普遍存在多重危险因素.结论:社区老年高血压患者多存在多重危险因素和较高比例的心脑血管并发症如高脂血症尤为突出,是社区防治的重点目标.  相似文献   

10.
Insulin-like growth factor II (IGF-II) plays a key role in mammalian growth, influencing foetal cell division and differentiation and possibly metabolic regulation. The mature 67 amino acid peptide shares sequence homology with both insulin and IGF-I. The liver is the main endocrine source of IGFs, but autocrine/paracrine activity is found in most tissues. The type 1 receptor mediates most of the biological effects of IGF-I and IGF-II; the type 2 receptor is involved with IGF-II degradation. Binding proteins may both localise IGFs to the receptors and regulate their activities. The IGF2 gene is maternally imprinted in mouse and human. Relaxation of IGF2 imprinting occurs in the Beckwith-Wiedemann syndrome of somatic overgrowth, sporadic Wilms' tumour and a number of other cancers. In the general adult population, the IGF2-INS gene cluster may also influence body weight, in which case IGF-II function could become a target for therapeutic intervention in obesity.  相似文献   

11.
The procoagulant activity observed in many types of tissue and cultured cells is due to tissue factor, a 30 kd transmembrane protein. The mRNA for tissue factor is a 2.2-kb species, which in some non-cancer cells can be up-regulated or induced by cytokines or by serum stimulation. In this study, induction of procoagulant activity in cancer cells was evaluated using the breast cancer cell line, MCF-7, and an adriamycin resistant subline, AdrRMCF-7, which has increased tumorigenicity in nude mice compared to the parental cell line. Procoagulant activity was factor VIIa dependent and was inhibited by an anti-tissue factor antibody. MCF-7 cells had minimal tissue factor activity, while AdrRMCF-7 cells had an 10-fold increase compared to the parental line. This increase was not observed in MCF-7 cells transfected with the multi-drug resistant gene, which is associated with adriamycin resistance. Serum stimulation of quiescent MCF-7 cells increased tissue factor activity 5-fold over baseline level, but did not increase activity in cells grown in serum-replete medium. Tissue factor activity of AdrRMCF-7 quiescent cells and AdrMCF-7 cells grown in serum-replete medium was enhanced 2-fold by serum stimulation. The predominant tissue factor mRNA species in MCF-7 cells was a 3.2 to 3.4-kb band, which increased in response to serum stimulation of cells grown in serum-replete medium. The mature 2.2-kb tissue factor mRNA band was detected in quiescent MCF-7 cells within six hours of serum stimulation and remained present 24 hours after stimulation. Synthesis of the 2.2-kb tissue factor mRNA species in MCF-7 and AdrRMCF-7 cells correlated with appearance of procoagulant activity. Thus, while procoagulant activity correlates with the level of the 2.2-kb tissue factor mRNA species in these cancer cells, there are inherent differences in tissue factor activity, antigen, and mRNA levels, as well as in regulation of its synthesis between these cells.  相似文献   

12.
Chelation therapy with deferoxamine is effective in preventing the risk of transfusional iron overload, but treatment failure is common because of noncompliance. To reduce the transfusional iron load, we have evaluated longterm erythrocytapheresis in 14 subjects with sickle cell disease and stroke (11) or other complications (3) as an alternative to simple transfusion. Subjects were treated with erythrocytapheresis using the Haemonetics V50 (Haemonetics Corp, Braintree, MA) to maintain the target pretransfusion hemoglobin S (Hb S) level less than 50% for 6 to 71 months. The transfusional iron load and the donor blood usage were analyzed for a 6- to 36-month study period and were compared with similar data from a subset of 7 subjects previously treated with conventional (target Hb S < 30%) and modified (target Hb S < 50%) simple transfusion protocols. The effect of erythrocytapheresis on iron accumulation was determined by assessment of serum ferritin levels in the absence of iron chelation. The mean transfusional iron load and donor blood usage with erythrocytapheresis were 19 +/- 14 mg iron/kg/yr (range, 6 to 50) and 188.4 +/- 55.2 mL packed-red blood cells (RBC)/kg/yr (range, 107 to 281), respectively. Of 6 subjects receiving no iron chelation therapy, 5 maintained normal or nearly normal serum ferritin levels during 11 to 36 months of erythrocytapheresis. In comparison with conventional simple transfusion and modified simple transfusion, erythrocytapheresis reduced iron loading by 87% (P < .01) and 82% (P < .01), respectively, but increased donor blood usage by 23% and 73%, respectively. Subjects with pre-erythrocytapheresis Hb levels > or = 8.0 g/dL had lower iron accumulation (P < .001) and less donor blood usage (P < .005) than subjects with Hb levels < or = 8.0 g/dL. Although donor blood usage is increased in comparison with simple transfusion, long-term erythrocytapheresis markedly reduces or prevents iron accumulation. This form of transfusion therapy allows the cessation of iron chelation in well-chelated subjects and, if used as the initial form of transfusion therapy, may prevent long-term complications of sickle cell disease without risk of iron overload and the need for chelation therapy.  相似文献   

13.
Sickle cell disease (SCD) is characterized by significant morbidity and early mortality. Children with this hemoglobinopathy exhibit many of the manifestations associated with immunodeficiency disorders. Serum was obtained from 56 healthy SCD subjects and 45 normal healthy controls. Type 2 cytokines interleukin (IL)-4, IL-6, and IL-10 serum levels were measured. Concentrations were determined by reference to a standard curve, and results were expressed in pg/mL. Results revealed significant levels of IL-4 in 6 (13%) of 45 SCD patients compared with 1 (2%) of 45 controls. Increased levels of IL-6 were present in 35 (78%) of 45 SCD patients and 12 (41%) of 29 controls. Elevated levels of IL-10 were detectable in 13 (41%) of 42 SCD patients and 1 (4%) of 25 controls. High circulating levels of type 2 cytokines may suppress both humoral and cell-mediated immune functions in SCD, with resultant increased morbidity.  相似文献   

14.
We describe two patients with sickle cell disease (SCD) who developed infections situated in the spleen. One patient had a splenic abscess and there was strong clinical evidence for an infected splenic infarct in the second patient. SCD predisposes to splenic infection because of functional hyposplenism, defective phagocyte function and splenic infarction. Splenic infections can occur in patients who might be considered to have an absent spleen and the diagnosis of splenic abscess should be considered in individuals with SCD who present with fever and abdominal pain.  相似文献   

15.
INTRODUCTION: Magnetic Resonance Imaging (MRI) has been proposed as the diagnostic technique of choice to characterize adrenal tumors. However, the results of the current studies are controversial. MATERIAL AND METHODS: Forty-nine patients with unilateral adrenal masses were submitted to MRI for lesion characterization on the basis of MR signal intensity. Cytology and/or histology demonstrated 14 pheochromocytomas (pheos), 11 adenomas, 3 cysts, 2 myelolipomas, 4 carcinomas, 3 metastases and 1 fibrosarcoma; a clinical diagnosis of adenoma was made in the remaining 11 patients. MR studies were performed using spin-echo (SE) sequences with T1 (TR/TE = 600/17 ms) and T2 (TR/TE = 2000/15-90 ms) weighting. T1-weighted images were also acquired after Gadolinium-DTPA (Gd-DTPA) administration. MR studies were integrated with in- and out-of-phase (TR/TE = 100/4-6 ms) chemical-shift (CS) sequences. MR signal intensity (SI) was analyzed qualitatively and quantitatively; MR results were correlated with tumor type and hormone secretion. RESULTS: The qualitative analysis of T2 images showed high signal intensity in the majority (80%) of adrenal lesions (14 pheos, 12 adenomas, 3 cysts, 2 myelolipomas and 8 malignancies). The quantitative analysis of post-Gd-DTPA T1 images permitted to distinguish adenomas, cysts and myelolipomas from pheos and malignancies. The qualitative analysis of post-Gd-DTPA T2 and T1 images permitted to distinguish pheos and cysts from adenomas and malignancies (p < .05); however, pheos and cysts as well as adenomas and malignancies were not differentiated. MR SI was similar in secreting and nonsecreting adenomas from both a qualitative and a quantitative viewpoints. CS MRI permitted to distinguish adenomas (decreased signal intensity on out-phase relative to in-phase images) from other benign and malignant lesions (no signal change from out-phase to in-phase images). CONCLUSIONS: The qualitative analysis of MR SI on conventional T1 and T2 images does not permit to differentiate adrenal masses. The qualitative evaluation of T1 images after Gd-DTPA administration, the quantitative analysis and CS sequences are technical options improving lesion characterization.  相似文献   

16.
A discrete neural circuit mediates the production of learned vocalizations in oscine songbirds. Although this circuit includes some bilateral pathways at midbrain and medullary levels, the forebrain components of the song control network are not directly connected across the midline. There have been no previous reports of bilateral projections from medullary and midbrain vocal control nuclei back to the forebrain song system, but the existence of such bilateral corollary discharge pathways was strongly suggested by the recent observation that unilateral stimulation of a forebrain song nucleus during singing leads to a rapid readjustment of premotor activity in the contralateral forebrain. In the present study, we used neuroanatomical tracers to demonstrate bilateral projections from (a) the rostral ventrolateral medulla (RVL), which may control respiratory aspects of vocalization, to nucleus uvaeformis (Uva), and (b) the dorsomedial intercollicular nucleus (DM), a midbrain vocal control region, to Uva. Both RVL and DM receive descending projections from the forebrain song nucleus robustus archistriatalis, and Uva projects directly to the forebrain song nuclei interfacialis and high vocal center. We suggest that the bilateral feedback projections from DM and RVL to Uva function to coordinate the two hemispheres during singing in adult songbirds and to convey internal feedback of premotor signals to the forebrain in young birds that are learning to sing.  相似文献   

17.
A lectin, which exerted a hypotensive action in rats after intravenous injection via the jugular vein, was isolated from the mycelia of the edible mushroom Tricholoma mongolicum. The lectin possessed a molecular weight of 37 K and its hypotensive activity was dose-dependent. Administration of the lectin at a dose of 10 mg/kg body weight caused a mean arterial blood pressure reduction of 95.3 +/- 7.4 mmHg. The lectin's hypotensive action was not mediated via autonomic ganglion transmission, alpha-adrenoceptors, beta-adrenoceptors, cholinergic receptors, histaminergic receptors, nor the renin-angiotensin system, but it was probably mediated through vasorelaxation via adenosine A2 receptors and/or nitric oxide production.  相似文献   

18.
The number and arrangement of scutellar bristles on the thorax of Drosophila melanogaster is largely invariant in wild-type stocks. This character therefore appears to be buffered against changes in phenotype, and has previously been described as a canalized character. Mutations that do alter this phenotype increase the variability in bristle number and can reveal otherwise cryptic genetic differences at other loci. This phenomenon is examined and possible mechanisms contributing to stability of this developmental event are discussed, but the notion that the character is canalized is found not to be heuristic.  相似文献   

19.
20.
It is demonstrated that fowlpox virus (FPV) protein FP26 located in the HindIII D fragment of the genome is related to the human deoxycytidine kinase (dCK) and probably possesses the same enzymatic activity. A homologous protein is not encoded by vaccinia virus. A multiple alignment of the amino acid sequences of the human and FPV dCKs, the thymidine kinases (TK) of herpesviruses, and cellular and vaccinia virus thymidylate kinases (ThyK) was generated and the conserved motifs, at least two of which are implicated in ATP binding, were characterized. An apparent duplication of ATP-binding motif B in the dCKs was revealed, leading to the reassignment of one of the catalytic residues. Phylogenetic analysis based on the multiple alignment suggested that the putative dCK of FPV probably has diverged from the common ancestor with the human dCK at a later stage of evolution than the herpesvirus TKs, with the ThyKs being peripheral members of the family. These results are compatible with hypothesis that genes for enzymes of nucleotide metabolism could be acquired independently by different DNA viruses (Koonin, E.V. and Senkevich, T.G., Virus Genes 6:187-196, 1992).  相似文献   

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