Correlation of T cell independence of antibody responses with antigen dose reaching secondary lymphoid organs: implications for splenectomized patients and vaccine design.
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Many natural viral and bacterial pathogens activate B cells independently of Th cells (TI Ags). This study analyzed the characteristics of the activation of B cells after immunization with various forms of viral Ags using different immunization routes and found a decreasing dependence on T help with increasing amounts of Ag recruited to the spleen. Repetitive antigenic structure facilitated TI B cell responses if Ag was present in lymphoid organs. These results suggest that 1) Ag dose and localization in secondary lymphoid organs are the key for B cell activation in the absence of T help; 2) early TI Ab responses are crucial to protect against systemically spreading acute cytopathic infectious agents; and 3) there may be new rationales for improved vaccine design. (+info)
Aspects of treatment. The anatomical basis for portal decompressive surgery.
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Definitive surgical techniques used in the treatment of portal hypertension all aim to achieve portal venous decompression. The historic development of the various procedures currently employed provides a broad repertoire of surgical operations. Each of the procedures merits consideration and may be specifically indicated in a given situation. Description of the operative steps emphasizes the importance of the anatomical relationships of the various structures. (+info)
Human lymphocyte subpopulations effect of epinephrine.
(51/1406)
The effect of administration of 0-2 mg of epinephrine (Parke-Davis) on circulatory lymphocytes was investigated in fifteen normal subjects. Blood samples were taken prior to, 10 and 20 min after, subcutaneous injections. Thymus-derived (T) cells were assayed by sheep red blood cell rosettes, bone marrow-derived (B) cells by their complement receptors and immunofluorescent detection of Fc receptors plus surface immunoglobulins. Their percentages prior to injections were 72-2 +/- 1-4, 13-8 +/- 1-1, and 20-3 +/- 1-3. Ten minutes after injections, the absolute concentrations of these cells increased to 164 +/- 14%, 326 +/- 57%, and 272 +/- 45% respectively of the values prior to injection (averages +/- standard errors). Further, when cells with receptors for both sheep red blood cells and complement were assayed by simultaneous rosette technique, they increased from 2-5 +/- 0-4% to 10-5 +/- 1-3% of the lymphocytes. Such changes were also observed in three subjects who had undergone splenectomy more than 2 years previously, but not in four subjects receiving injections of saline instead of epinephrine. (+info)
Severity of iron overload in patients with sickle cell disease receiving chronic red blood cell transfusion therapy.
(52/1406)
Chronic transfusion therapy is being used more frequently to prevent and treat the complications of sickle cell disease. Previous studies have shown that the iron overload that results from such therapy in other patient populations is associated with significant morbidity and mortality. In this study we examined the extent of iron overload as well as the presence of liver injury and the predictive value of ferritin in estimating iron overload in children with sickle cell disease who receive chronic red blood cell transfusions. A poor correlation was observed between serum ferritin and the quantitative iron on liver biopsy (mean 13.68 +/- 6.64 mg/g dry weight; R = 0.350, P =.142). Quantitative iron was highly correlated with the months of transfusion (R = 0.795, P <.001), but serum ferritin at biopsy did not correlate with months of transfusion (R = 0.308, P =.200). Sixteen patients had abnormal biopsies showing mild to moderate changes on evaluation of inflammation or fibrosis. Liver iron was correlated with fibrosis score (R = 0.50, P =.042). No complications were associated with the liver biopsy. Our data suggest that, in patients with sickle cell disease, ferritin is a poor marker for accurately assessing iron overload and should not be used to direct long-term chelation therapy. Despite high levels of liver iron, the associated liver injury was not severe. (+info)
Splenectomy selectively affects the distribution and mobility of the recirculating lymphocyte pool.
(53/1406)
The spleen plays a major role in immune surveillance, but the impact that splenectomy exerts on the immune competence of an individual is not fully resolved. Here we show that neonatal splenectomy in sheep does not abrogate the development of a large, nonrecirculating pool of lymphocytes and that it has no effect on the acquisition of a normal blood lymphocyte profile. Splenectomy did, however, result in a significant decrease in blood residency time of recirculating lymphocytes and in an enhanced accumulation of recirculating lymphocytes in lymph nodes. Furthermore, nonrecirculating peripheral blood lymphocytes were less likely to migrate to the lung, possibly because of saturation of the marginal pool by recirculating lymphocytes. Although splenectomy has little effect on the development or distribution of lymphocyte subsets in blood and lymph, it has marked effects on the rate of recirculation of lymphocytes, which may have significant implications for peripheral immune surveillance in patients who undergo splenectomy. (+info)
Laparoscopic splenectomy in pediatric patients with hematologic diseases.
(54/1406)
OBJECTIVE: The aim of this study was to evaluate our experience with laparoscopic splenectomy in pediatric patients with hematologic diseases. METHODS: A retrospective chart review was performed to analyze the following: indication for splenectomy, pre- and peri-operative management, surgical technique, complications, duration of hospitalization, and outcome. RESULTS: Eleven patients underwent laparoscopic splenectomy for the following indications: recurrent thrombocytopenia (<10,000) in seven with chronic immune thrombocytopenic purpura; anemia in two with hereditary spherocytosis; and hypersplenism in one and recurrent splenic sequestration in another with homozygous hemoglobin S. The six girls and five boys had a median age of 7 years. The median operative time was 180 minutes, and the median hospitalization was 72 hours. Among the patients with immune thrombocytopenic purpura (median platelet count, 153,000), those patients (n=3) with platelet counts of <100,000 did not suffer any bleeding complications. The patient with hypersplenism and homozygous hemoglobin S required a small incision in the left lower quadrant to facilitate removal of a 558-gram spleen. This patient also underwent cholecystectomy for cholelithiasis. The operative time was 295 minutes, and he was hospitalized for 5 days because of atelectasis. CONCLUSIONS: Laparoscopic splenectomy is a safe and effective procedure in children with hematological disorders. (+info)
Pancreatic injury: an audit and a practical approach.
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Pancreatic injuries are uncommon, difficult to diagnose and there is no uniform standard for treatment. The purpose of this study was to audit the management of pancreatic injuries in our practice. Equally important is to attempt to find out a simple management plan particularly in the era of increasing conservative treatment of injured patients. There were 22 cases of pancreatic injury. The average Glasgow coma scale of 10.9 and injury severity score of 29.1. When computed tomography is used it has a sensitivity of 33.3% which became 100% if repeated or other injuries were identified. There was one case in grade I which was treated non-operatively. There were 15 patients in grade II and they were treated by drainage. Distal pancreatectomy and splenectomy was the treatment of 3 patients with grade III injury. One patient had pancreatico-jejunostomy for grade IV injury and subsequently developed pancreatic fistula. Pancreaticoduodenectomy was the treatment of choice for two patients with grade V and both subsequently died. The over all mortality of this series was 22.7% and intra-abdominal abscesses noted in 9.1%. This series indicated that there is a need to adopt 'bail out' procedures particularly in grade IV and V pancreatic injury. A simplified management plan is suggested. (+info)
Report of the Spanish Gaucher's disease registry: clinical and genetic characteristics.
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BACKGROUND AND OBJECTIVES: Since 1993 the demographic, clinical, analytical, genetic and follow-up data of Spanish patients with Gaucher's disease (GD) have been collected in an anonymous national database. Some statistical analyses of these data are reported concerning the distribution, clinical and genetic characteristics of GD in Spain and the response to enzyme replacement therapy (ERT) is evaluated. DESIGN AND METHODS: We performed a cohort study in Spanish GD patients by national inquiry, submitted by mail to 75 Spanish hospitals (over 300 beds) directed to internal medicine, hematology and pediatric departments. The questionnaire included 30 questions (gender, height, weight, date of birth, date of diagnosis, abode and number of relatives affected, bone crises, neurologic symptoms, other symptoms, liver and spleen size, hemoglobin, leukocyte and platelet count, tartrate resistant acid phosphatase, ALT/AST, chitotrioxidase activity, total plasma cholesterol, triglycerides, high density lipoprotein cholesterol, enzymatic activity of acid -glycosides, mutation, X-ray examination, magnetic resonance imaging-MRI-evaluation, spleen removal, and orthopedic procedures (ERT, date of first infusion). Each case with a presumed diagnosis was considered an enrolled patient. Written informed consent was obtained from all patients. The cases without enzymatic or genetic diagnosis were studied in a reference laboratory (the same for all the samples). Clinical status was evaluated by Zimran's severity score index. The enzymatic activity of acid -glycosides was determined in cellular extracts of peripheral blood granulocytes by a fluorescent method using an artificial substrate (4-methyl-umbelliferyl -D-glycoside). Polymerase chain reaction (PCR) molecular analysis was performed in DNA samples to characterize the mutations (N370S, L444P, IVS2+1, 84GG, D409H, R463C and G377S) of the glycoside genes. Two groups were created according to age at diagnosis: children under 15 years and adults, in order to evaluate clinical, genetics and follow-up. Effectiveness of ERT was evaluated using objective parameters (hemoglobin, platelets, liver and spleen size, skeletal lesions), before and after therapy. In patients under ERT, quality of life (QOL) was assessed by a SF-36 modified inquiry, including 22 questions. Statistical analysis including descriptive and frequency distribution for each variable was performed, the ANOVA test was used to identify differences between groups. Paired t-tests (before and during therapy) were carried out. The degree of linear association among measured variables was estimated by Pearson's correlation. RESULTS: By December 1999 one hundred and fifty-five patients from 117 families had been included from 66 Spanish Hospitals; the inquiry was complete for 114 patients. Mean age at diagnosis: 24.0+/-16.9 years, M/F: 72/83. No symptoms were present at diagnosis in 19.3%; visceral disease was present in 95.6% and bone disease in 62.4%. Hemoglobin levels, leukocyte and platelet counts were below the normal range in 62.3% of cases. Higher acid phosphatase levels were observed in 99% of cases; biochemical liver dysfunction tests were found in 42.9%. The test for acid glycosidase showed a marked decrease in enzymatic activity. Morphologic documentation (spleen or liver tissue, bone marrow biopsy or aspirate) of GD was obtained in 71% of the patients. The most frequent mutations observed were N370S (46.3% of the alleles detected), and L444P (18.5%). In 18.7% of the cases the disease was stable or progressing slightly; in 23.8% the spleen had been removed between 1-14 years after diagnosis and 60.6% were under ERT. Children showed both greater liver enlargement and higher SSI (p = 0.0001). There was a correlation between SSI and clinical or analytical data in adults patients for spleen size (Z: 3.142; CI: 0. 173-0.637; p= 0.0017). In 35 patients on ERT, clinical and analytic data improved as did self-evaluated QOL (p< 0.0001). (A (+info)