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1.
Field isolates of Plasmodium falciparum collected from endemic areas of Southeast Asia, Solomon Islands, tropical African countries and Brazil were analyzed for the genetic diversity of the exon II of serine repeat antigen gene (SERA) by sequencing of genomic DNA. Of sixty-nine isolates, as compared to the reported FCR3, K1 and Honduras-1 types of exon II sequences, 5, 9 and 20 new allelic forms were found in 23 isolates of the FCR3 type, 36 of the K1 type and 10 of the Honduras-1 type. A group of novel non-synonymous substitutions, 4 new insertions and 3 new deletions of octamer units were found in the octamer repeat region (OR) of the exon II, and most of them clustered within a 40-residues domain. An octamer "SNPVSSEP" revealed in the OR was confirmed as a new repeat unit. Based on the sequences of the serine repeat region (SR) of the exon II, the allelic forms of the Honduras-1 type were conjectured to be the recombinant forms between the K1 type and FCR3 type. The allelic forms of K1 type with less or more repeat serine residues in the serine stretch of the SR than the reported 21 serine residues had most of the variations in the OR. Moreover, a biased geographical distribution of allelic forms was observed. Isolates from African and Southeast Asian countries accounted for most of the new allelic forms (29/33). All of the three types were detected in Southeast Asia but none of the FCR3 type in Africa. One of two groups of FCR3 new allelic forms was found solely in Brazil while another was mainly in Solomon Islands.  相似文献   

2.
Cat-scratch disease (CSD) is the most frequent presentation of Bartonella henselae infection. It has a worldwide distribution and is associated with a previous history of scratch or bite from a cat or dog. CSD affects children and teenagers more often (80%) than adults, and it usually has a self-limiting clinical course. Atypical clinical course or systemic symptoms are described in 5%–20% of patients. Among them, hepatosplenic (HS) forms (abscess) have been described. The majority of published cases have affected children or immunosuppressed patients. Few cases of HS forms of CSD in immunocompetent adult hosts have been reported, and data about the management of this condition are scarce. Herein, we present 3 new cases of HS forms of CSD in immunocompetent adults and review 33 other cases retrieved from the literature. We propose an approach to clinical diagnosis and treatment with oral azithromycin.  相似文献   

3.
In a series of 100 patients with intracardiac myxoma, the lesion was in the right atrium in 10 cases. The authors attempt to define the particular features of right atrial myxoma in terms of clinical aspects, outcome and pathology. The diagnostic difficulty raised by complex clinical pictures (including right ventricular failure, pseudopericardial forms and forms with a predominance of systemic problems) has now been resolved by imaging and, above all echocardiography. Consequences for the right side of the heart may involve the pulmonary artery with myxomatous emboli causing multiple fusiform aneurysms and pulmonary hypertension, or, more rarely, the tricuspid (with need for valve replacement), vena cava (Budd-Chiari syndrome) or atrial septum (right/left shunt). Alongside systemic problems due to interleukin 6, erythrocyte abnormalities are a new feature. Frequent etiological inclusion in a Carney complex explains recurrences and multi-cavity forms. The dominant pathological feature is tumor calcifications, no doubt as a result of the long presymptomatic phase of myxoma.  相似文献   

4.
溶血离心培养法检测肺结核患者外周血分支杆菌及其L型   总被引:14,自引:4,他引:10  
目的 建立一种自血液中分离分支杆菌及其L型的新方法。方法 肺结核患者的外周血直接或溶血离心后取沉淀种入 92 3TB和 92 3TBL液体培养基培养 ,培养物用免疫酶染色 (ABC法 )鉴定。结果  6 5份标本分支杆菌和分支杆菌L型血培养的阳性率、总检出率分别为 15 %、2 6 %、32 % ;溶血离心培养法的阳性率明显高于直接培养法 (P <0 0 5 ) ;相应痰培养中 ,抗酸杆菌和抗酸菌L型的阳性率、总检出率分别为 38%、2 0 %和 5 2 % ,高于肺结核患者外周血培养的阳性率 (P <0 0 5 ) ;但血、痰配对检测总阳性率可达 6 5 %。结论 肺结核患者外周血存在分支杆菌及其L型 ,并以L型为主 ;溶血离心液体培养结合免疫酶染色可常规用于检测血液中分支杆菌及其L型 ;结合痰标本检测 ,可提高肺结核患者细菌学检查的阳性率  相似文献   

5.
6.
The aim of this study was to characterize the molecular wt forms of inhibins A and B and its free alpha-subunit present in serum from women with ovarian cancer as a basis for developing improved monoclonal antibody-based inhibin assays for monitoring ovarian cancer. Three new inhibin alpha-subunit (alphaC) ELISAs were developed using monoclonal antibodies directed to three nonoverlapping peptide regions of the alphaC region of the inhibin alpha-subunit. To characterize serum inhibin molecular wt forms present in women with ovarian cancer, existing inhibin immunoassays (inhibin A, inhibin B, and pro-alphaC) and the new alphaC ELISAs were applied to sera from women with granulosa cell tumors and mucinous carcinomas previously fractionated using a combined immunoaffinity chromatography, preparative SDS-PAGE, and electroelution procedure. The distribution and molecular size of dimeric inhibins and alpha-subunit detected were consistent with known mol wt forms of inhibins A and B and inhibin alpha-subunit and their precursor forms present in serum and follicular fluid from healthy women. The alphaC ELISAs recognized all known forms of inhibin and the free inhibin alpha-subunit, although differences between alphaC ELISAs were observed in their ability to detect high mol wt forms. To assess which of the alphaC ELISAs was preferred in application to ovarian cancer, the alphaC ELISAs were applied to serum from a range of normal postmenopausal women (n = 61) and postmenopausal women (n = 152) with ovarian (serous, mucinous, endometrioid, clear cell carcinomas, and granulosa cell tumors) and nonovarian (breast and colon) cancers. Despite differences in their ability to detect high mol wt forms of inhibin, the alphaC ELISAs showed similar sensitivity (i.e. proportion of cancer patients correctly detected) and specificity (proportion of controls correctly detected) indexes in the detection of mucinous carcinomas (84% and 95%) and granulosa cell tumors (100% and 95%) compared with earlier inhibin RIA or polyclonal antibody-based immunofluorometric assays. A combination of the alphaC ELISAs with the CA125 assay, an ovarian tumor marker that has a high sensitivity and specificity for other ovarian cancers (serous, clear cell, and endometrioid), resulted in an increase in sensitivity/specificity indexes (95% and 95%) for the all ovarian cancer group. These new monoclonal antibody-based inhibin alphaC ELISAs now provide practical and sensitive assays suitable for evaluation as diagnostic tests for monitoring ovarian cancers.  相似文献   

7.
Synovial fluid eosinophilia is defined as the presence of eosinophils, irrespective of quantity, in the synovial fluid and is a rare finding that is probably underestimated. The pathogenesis of this entity remains incompletely understood. Secondary and idiopathic forms have been described. Idiopathic forms are those not associated with systemic or rheumatic inflammatory disease or associated with chronic non-inflammatory rheumatic diseases. Idiopathic forms can be divided into pure or pseudoallergic forms when they occur in patients with an atopic background and/or intensely positive dermographism. Both forms are usually monoarthritis of the large joints with a substantial component of joint effusion but few inflammatory signs. Synovial fluid usually contains between 2,000 and 10,000 leukocytes/mm3, with a variable percentage of eosinophils. Although a major form (>10% eosinophils) and a minor form (<10% eosinophils) have been distinguished, both seem to have the same significance in terms of clinical manifestations and prognosis. Peripheral eosinophilia (>600 eosinophils/mm3) is a rare association and is not usually severe. Symptoms resolve within a few days without specific therapy and recurrences occur in approximately half of patients. Non-steroidal anti-inflammatory drugs are usually sufficient to control symptoms. Synovial fluid eosinophilia has not been associated with the development of new joint deformities nor has it been described as a chronic form of arthritis.  相似文献   

8.
H. Y. Reynolds 《Lung》1996,174(4):207-224
Respiratory infections, especially community-acquired forms of pneumonia (CAP), are challenging for clinicians because (1) a causative microorganism can only be found in about 50% of cases; (2) initial therapy, therefore, must be based on a probable or most likely etiology in the context of the patient's overall medical condition; and (3) new microbes or those considered previously as normal flora or less virulent forms seem responsible for some cases. It is important to be acquainted with new causes of infection which include Legionella species, Chlamydia pneumoniae, diphtheroids in certain instances (Corynebacterium pseudodiphtheriticum), and viruses such as the Hanta strains. Infections with Bordetella pertussis are increasing. However, the ever present and most common cause of CAP, Streptococcus pneumoniae, continues to present problems because of increasing antibiotic resistance, the high case fatality rate when bacteremia accompanies pneumonia, and the inability to give prophylactic immunization to all people with risk factors for this infection. Offprint requests to: H. Y. Reynolds  相似文献   

9.
Ischaemic or haemorrhagic cerebral vascular accidents (CVA) are the second cause of premature death in Western countries. Their pathophysiological mechanisms are very heterogeneous and implicate environmental and genetic factors. The recent identification of several genes implicated in the rare monogenic forms of CVA, such as hereditary cerebral amyloid angiopathy, cerebral cavernous angioma or CADASIL, has had immediate diagnostic applications for patients and their relatives, and has opened new insights into the mechanisms governing angiogenesis and/or vascular homeostasis. In the multifactorial forms of CVA, by far the most frequent, the role of a genetic factor is much more moderate, making identification of the implicated genes difficult. A very great number of association studies have been performed in order to examine the possible implication of candidate genes due to their known or supposed functions, but very few genetic variants have been associated with an increased risk of CVA, this increase being modest moreover. Quite recently an approach combining genetic linkage analysis and a haplotypic association study has allowed the localisation and identification of a new gene, phosphodiesterase 4D, implicated in ischaemic CVA, and the localisation on chromosome 7 of a gene implicated in the occurrence of cerebral aneurysms, thus raising new hopes in these multifactorial form.  相似文献   

10.
11.
DEFINITION AND CLASSIFICATION: Cardiomyopathies are disorders affecting the heart muscle that frequently result in congestive heart failure. Five major forms are recognized: dilated, hypertrophic, restrictive, right ventricular, and nonclassifiable cardiomyopathies with distinct hemodynamic properties. Furthermore, the new WHO/WHF definition also comprises inflammatory cardiomyopathy, defined as myocarditis in association with cardiac dysfunction. Idiopathic, autoimmune, and infectious forms of inflammatory cardiomyopathy were recognized. Viral cardiomyopathy is defined as viral persistence in a dilated heart. It may be accompanied by myocardial inflammation and then termed inflammatory viral cardiomyopathy (or viral myocarditis with cardiomegaly). If no inflammation is observed in the biopsy of a dilated heart (< 14 lymphocytes and macrophages/mm2), the term viral cardiomyopathy or viral persistence in dilated cardiomyopathy should be applied. DIAGNOSIS AND TREATMENT: In recent years, there have been breakthroughs in understanding the molecular and genetic mechanisms involved in this group of conditions, enabling improvement of diagnostic strategies and introduction of new therapies. Ongoing evaluation of antiviral, immunoglobulin, and immunosuppressive therapies including the European Study of Epidemiology and Treatment of Cardiac Inflammatory Diseases (ESETCID), removal of antibodies by immunoadsorption, anticytokine and gene therapy, as well as the mechanical support devices may provide new treatment options.  相似文献   

12.
Individuals with severe forms of congenital neutropenia suffer from recurrent infections. The therapeutic use of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to increase the neutrophil count is associated with fewer infections and an improved quality of life. However, the long-term effects of this new therapy are largely unknown. In particular, it is unclear if myeloid leukemia, a known complication of some forms of congenital neutropenia, will occur with increased frequency among patients who receive long-term treatment with hematopoietic growth factors. We report 13 patients with congenital disorders of myelopoiesis who developed leukemic transformation with either myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML) and 1 who acquired a clonal cytogenetic abnormality without evidence of MDS or AML while receiving rhG-CSF. The bone marrows of 10 patients showed monosomy 7 and 5 had activating RAS mutations. These abnormalities were not detected in pretreatment bone marrows and cessation of rhG-CSF was not associated with either clinical improvement or cytogenetic remission. We conclude that patients with severe forms of congenital neutropenia are at relatively high risk of developing MDS and AML. The occurrence of monosomy 7 and RAS mutations in these cases suggests that the myeloid progenitors of some patients are genetically predisposed to malignant transformation. The relationship between therapeutic rhG-CSF and leukemogenesis in patients with severe chronic neutropenia is unclear.  相似文献   

13.
Lack of insulin production or abnormalities affecting insulin secretion are key to the development of almost all forms of diabetes, including the common type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes and the more rare forms of maturity-onset diabetes of the young (MODY). Because insulin has such a central role in the pathogenesis of both forms of diabetes, the insulin gene (INS) has always been considered a candidate susceptibility gene. A number of studies have shown that the allelic variation and parent-of-origin effects affect the transmission and expression of the insulin gene in pancreatic beta-cells and extra-pancreatic tissues. These observations have led to the formulation of new hypotheses to explain the biological mechanisms by which functional differences in the expression of the insulin gene may contribute to diabetes susceptibility.  相似文献   

14.
Recent advances in the treatment of cystinosis   总被引:4,自引:0,他引:4  
Summary Cysteamine bitartrate capsules (Cystagon) have been approved by the US Food and Drug Administration for use in patients with nephropathic cystinosis. Plasma cysteamine concentrations were virtually identical at various times following ingestion of either cysteamine hydrochloride or Cystagon capsules in 24 normal control subjects. A transfer study was done with eight cystinosis patients who had been receiving either cysteamine hydrochloride or phosphocysteamine for many years. The plasma cysteamine concentration was significantly higher 2h after Cystagon and the leukocyte cystine content was significantly lower at all times after Cystagon compared to older forms of the drug. These differences are probably the result of greater patient compliance in taking the capsules compared to the older, liquid forms of the drug. A new method for following the course of renal glomerular deterioration in diseases such as cystinosis has been published recently. This method was used to re-analyse data on the efficacy of cysteamine treatment and to re-analyse new data on treating cystinosis patients with either of two doses of cysteamine (1.30 g/m2 per day and 1.95 g/m2 per day). This new method agrees well with other methods and shows that both doses of drug are equally effective in maintaining glomerular function.  相似文献   

15.
Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy (TMA) disorder characterised by the association of haemolytic anaemia, thrombocytopenia and acute renal failure. Atypical forms (non-shigatoxin related forms) may be familial or sporadic, frequently with relapses and most of them lead to end stage renal failure. During the last years, different groups have demonstrated genetic predisposition to atypical HUS (aHUS) involving five genes encoding for complement components which play a role in the activation or control of the alternative pathway: encoding factor H (CFH), accounting for 30% of aHUS; CD46 (encoding membrane cofactor protein [MCP]) accounting for approximately 10% of aHUS; CFI (encoding factor I) accounting for an estimated 5-15% of patients; C3 (encoding C3) accounting for approximately 10% of aHUS; and rarely CFB (encoding factor B). Predisposition to aHUS is inherited with incomplete penetrance. It is admitted that mutations confer a predisposition to develop aHUS rather than directly causing the disease and that a second event (genetic or environmental) is required for disease manifestation. HUS onset follows a triggering event in most cases (frequently banal seasonal infection and pregnancy). Uncontrolled C3 convertase leads to increased deposition of C3b on vascular endothelium and participates to the prothrombotic state. The phenotype of aHUS is variable ranging from mild forms, with complete recovery of renal function to severe forms with end stage renal disease within the first year after the onset. Overall, the outcome is severe with a mortality rate of 10% and with more than 60% of patients on dialysis. The most severe prognosis was in the CFH mutation group. There is a high risk of recurrence of the disease after renal transplantation in patients with mutations in CFH, CFI, CFB and C3. Plasma therapy may allow complete haematological remission but frequently with persistent renal damage. Some patients are plasma resistant and some are plasma dependent. The recent progress in the determination of the susceptibility factors for aHUS, have allowed to propose new diagnostic tests including a molecular genetic testing and may permit to consider some new specific treatments in this disease (human plasma-derived CFH or complement inhibitors).  相似文献   

16.
Each megakaryocyte forms 10(3) platelets and 10(11) platelets are replenished daily. The unique and amazing mechanisms that allow megakaryocytes to become giant and polyploid and to release such a large number of platelets are still poorly understood. The study of inherited thrombocytopenias offers the possibility to gain new information on these processes because several different forms, deriving from defective megakaryocytic commitment, differentiation, maturation, or platelet formation, have been identified. Moreover, in the presence of some genetic defects, megakaryocytes produce platelets with a shortened life span. In this review, we summarize what we have learned about inherited thrombocytopenias in the last few years.  相似文献   

17.
This study compared the effect of two forms of chest physiotherapy. In the "conventional" form of physiotherapy, postural drainage was combined with percussion and directed coughing. The other, relatively new form of physiotherapy, was the forced expiration technique, i.e. huffing combined with postural drainage, breathing exercises and, if necessary, coughing. Eight patients (six with cystic fibrosis, two with agammaglobulinaemia) took part in the study. No difference was found in tracheobronchial clearance, regional lung clearance, sputum production or lung function between the two forms of treatment. The forced expiration technique can be performed without an assistant. Therefore, it is concluded that in general the forced expiration technique is preferable.  相似文献   

18.
Fatty liver disease (FLD) represents a common form of hepatic dysfunction among adults and children. Recognition of steatosis is usually straightforward but the differential diagnosis is broad. Macrovesicular steatosis may occur due to alcohol use or metabolic factors including obesity and hyperinsulinemia. Steatosis is, in some patients, accompanied by varying degrees of inflammation, ballooning hepatocyte degeneration or fibrosis, or both. The pathologist's recognition and interpretation of these features, when present, is critical for the classification and prognostication of the disease. Recent advances in the study of FLD have yielded new information for the surgical pathologist to guide the interpretation of steatosis in children and adults, and in patients with other forms of liver disease such as chronic viral hepatitis. This article details the current terminology for various forms of FLD, highlights the key histological features and reviews recent advances in the field.  相似文献   

19.
Three different killer specificities in U. maydis are inherited cytoplasmically and transmitted by cell fusion. Each killer generates low frequencies of specifically immune forms in crosses with sensitive strains. The properties of immunity to each killer are also inherited cytoplasmically and transmitted by cell fusion. Killer strains carry virus-like particles about 41 nm in diameter. Each killer possesses distinct double-stranded RNA components that range in molecular weight from 0.46 X 10(6) to 2.9 X 10(6). Two components are shared by all three killers. Immune strains possess new forms. Crosses and heterokaryons between different killers revealed unilateral or mutual restrictions that prevent inclusion of two killer specificities in the same cell.  相似文献   

20.
Over the past two decades, the genetic and molecular basis of familial forms of diabetes insipidus has been elucidated. Diabetes insipidus is a clinical syndrome characterized by the excretion of abnormally large volumes of diluted urine (polyuria) and increased fluid intake (polydipsia). The most common type of diabetes insipidus is caused by lack of the antidiuretic hormone arginine vasopressin (vasopressin), which is produced in the hypothalamus and secreted by the neurohypophysis. This type of diabetes insipidus is referred to here as neurohypophyseal diabetes insipidus. The syndrome can also result from resistance to the antidiuretic effects of vasopressin on the kidney, either at the level of the vasopressin 2 receptor or the aquaporin 2 water channel (which mediates the re-absorption of water from urine), and is referred to as renal or nephrogenic diabetes insipidus. Differentiation between these two types of diabetes insipidus and primary polydipsia can be difficult owing to the existence of partial as well as complete forms of vasopressin deficiency or resistance. Seven different familial forms of diabetes insipidus are known to exist. The clinical presentation, genetic basis and cellular mechanisms responsible for them vary considerably. This information has led to improved methods of differential diagnosis and could provide the basis of new forms of therapy.  相似文献   

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