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1.
Primer pairs for PCR were designed from the gene encoding the 17,000-molecular-weight genus-common antigen of Rickettsia japonica, Rickettsia rickettsii, Rickettsia conorii, Rickettsia typhi and Rickettsia prowazekii. Primers R1, R2 were designed for amplifying the genomic DNA from spotted fever group (SFG) rickettsiae and epidemic typhus rickettsiae. Primers Rj5, Rj10 were designed for amplifying the genomic DNA from only R. japonica. Using the primers R1, R2, about a 540-bp fragment was observed by amplifying the genomic DNA from R. japonica, R. rickettsii, R. conorii, Thai tick typhus TT-118, Rickettsia sibirica, Rickettsia montana, Rickettsia askari, R. typhi, R. prowazekii and Katayama strain isolated from the patient infected with SFG rickettsiae. Using the primers Rj5, Rj10, the 357-bp fragment was observed by amplifying the genomic DNA from R. japonica and Katayama strain. Therefore, the Katayama strain was identified to belong to R. japonica. With primers R1, R2 and Rj5, Rj10, 537 bp and 357 bp bands were amplified from blood of the patients infected with SFG rickettsiae in Kanagawa prefecture. These findings indicate that the causative agent of SFG rickettsiosis in these two patients was R. japonica. The ticks, Ixodes ovatus and Haemaphysalis flava, were collected by out field research in Kanagawa prefecture. With primers R1, R2 and Rj5, Rj10, 537 bp and 357 bp were amplified from these ticks. This indicates that I. ovatus and H. flava were the vector of R. japonica in Kanagawa prefecture. Also, with the primers R1, R2, about a 540 bp fragment was amplified but with primers Rj5, Rj10, no fragments were amplified from I. ovatus and H. flava. Therefore, these ticks may have SFG rickettsiae other than R. japonica and epidemic typhus rickettsiae.  相似文献   

2.
Using pulsed-field gel electrophoresis, we studied the chromosomes of spotted fever group rickettsiae. We digested the DNA of 16 species currently known to belong to this group with SmaI, EagI, and BssHII. The genome size of 13 rickettsiae was between 1,200 and 1,300 kb. "Rickettsia massiliae" and "R. helvetica" genome sizes were 1,370 and 1,397 kb, respectively, and that of R. bellii was 1,660 kb. It was possible to obtain distinctive patterns for each species, but in R. conorii, 10 isolates exhibited the same profiles, showing that pulsed-field gel electrophoresis is a good interspecies identification tool. We achieved a phylogenetic analysis of these bacteria by using the Dice coefficient and UPGMA and Package Philip programming. We established a dendrogram of the genetic relationships between the different species showing the existence of a cluster in the spotted fever group rickettsiae including R. conorii, R. rickettsii, R. parkeri, R. sibirica, "R. africae," "R. slovaca," Thai tick typhus rickettsia, and Israeli tick typhus rickettsia. We located three genes previously cloned and sequenced (genes encoding the R. rickettsii surface proteins of 120 and 190 kDa and the R. prowazekii citrate synthase gene), using Southern hybridization. The genes encoding citrate synthase and the surface protein of 190 kDa were usually located on the same band, and it is hypothesized that they are relatively close on the chromosome.  相似文献   

3.
The spotted fever group (SFG) is made up of more than 20 different rickettsial species and strains. Study of the taxonomic relationships among the group has been attempted by phenotypic, genotypic, and phylogenetic analyses. In this study, we determined taxonomic relationships among the SFG rickettsiae by comparative analysis of immunogenic epitopes reactive against a panel of monoclonal antibodies. A total of 98 monoclonal antibodies, which were directed against epitopes on the major immunodominant proteins or on the lipopolysaccharide-like antigens of strains of Rickettsia africae, Rickettsia conorii, Rickettsia massiliae, Rickettsia akari, Rickettsia sibirica, and Rickettsia slovaca, were used in the study. The distribution and expression of the epitopes among 29 SFG rickettsiae and Rickettsia bellii were assessed by determination of reaction titers in a microimmunofluorescence assay. The results were scored as numerical taxonomic data, and cluster analysis was used to construct a dendrogram. The architecture of this dendrogram was consistent with previous taxonomic studies, and the implications of this and other findings are discussed.  相似文献   

4.
Tick-borne rickettsioses are important zoonoses in many tropical and subtropical areas. There has recently been an increase in the number of reported cases among tourists returning to Scandinavia. In this article we present all five serologically confirmed cases of tick-borne rickettsioses imported into Norway in 1997. The patients were Norwegian tourists who had visited South Africa (three cases), Zimbabwe, and Italy. Four cases had typical eschar and three had maculopapular exanthema. The patients were treated with either doxycycline or ciprofloxacin. No complications were reported. The diagnosis of tick-borne rickettsiosis was confirmed by the detection of specific IgM antibodies to Rickettsia conorii using micro-immunofluorescence in serum samples.  相似文献   

5.
The effect of Ogi-Keishi-Gomotsu-To-Ka-Kojin (OKGK), a traditional Chinese herbal medicine (Kampo medicine), on cholesterol metabolism was studied in male Sprague-Dawley rats. Intake of OKGK at doses of 1.38 g/kg for 4 weeks significantly reduced total cholesterol levels in the serum and liver of hypercholesterolemia rats fed a cholesterol-enriched diet. OKGK suppressed cholesterol absorption through the intestine and stimulated excretion of cholesterol into feces as bile acids. Biochemical study indicated that OKGK treatment enhanced cholesterol 7alpha-hydroxylase activity the rate limiting enzyme of cholic acid synthesis, in the liver without any effect on the rate limiting enzyme of cholesterol synthesis, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. Further, cholesterol-enriched diet containing cholic acid suppressed cholesterol 7alpha-hydroxylase activity, whereas OKGK administration reversed the suppression. In conclusion, these results supported the idea that OKGK may be an effective agent for treatment of patients with hypercholesterolemia.  相似文献   

6.
Most of the basic knowledge about radical reactions comes from radiation chemical studies in vitro. In view of the rapidly increasing knowledge on radical reaction in vivo, it is important to reconcile the fundamental physico-chemical reaction characteristics of radicals with the need to explain their alleged biological effects. Severe problems in the understanding of their in vivo action remain unsolved. An example is phagocytosis, which seems to be a paradigm of a 'deleterious' radical process. The exact mechanism is not clear; so it is an open question whether the intruder is eventually killed by radicals (like OH) or by endproducts of radical reactions (like H2O2 and/or HOCl). It is even more difficult to understand signalling by radicals: owing to their chemical nature they are 'unspecifically' reacting species--they withdraw or add electrons--and thus their reactions are governed by redox-properties. Since all radicals have different redox characteristics and different molecular shapes, the usual key-and-keyhole picture for molecular interaction does not apply, as there, is no reactive site conceivable which has the property of reacting with radicals 'specifically. Our intent in this article is: (i) to briefly review some fundamental characteristics of in vitro radical reactions, (ii) to extrapolate from this to the conditions in vivo, and (iii) to discuss current hypotheses concerning the redox-regulation of cellular signalling. This leads us to the tentative conclusion that radicals per se must be tolerated by the cell and do not threaten its life, if they stay below a certain concentration limit. The main biological implication of radical-reactions seems to be that the cell derives signals from the balance of oxidative versus reductive processes and that radicals may interact with pathways of intra- and intercellular communication.  相似文献   

7.
Sedation in children poses a great challenge, with the main concern one of safety. The importance of providing adequate sedation to children was realized only in the last decade and a half, and relevant data are severely lacking. Use of potent sedative agents is not without risk. Children are given sedative agents in a wide variety of settings by practitioners with different degrees of experience with the drugs and management of adverse effects. Controversial issues must be addressed in this area, and appropriate tools developed to measure sedation and individualize treatment based on the drugs' pharmacokinetic and pharmacodynamic properties.  相似文献   

8.
The purpose of this review is to present current information from the literature regarding the pathoanatomy, clinical presentation, differential diagnosis, treatment, and outcome assessment methods for patients with lumbar spinal stenosis. Lumbar spinal stenosis is a frequently encountered condition, particularly in the elderly. Treatment requires an accurate diagnosis, but differential diagnosis of lumbar stenosis can be difficult. The literature to date has focused primarily on surgical treatment. The long-term efficacy of surgery has been questioned, and surgical procedures are associated with increased costs and risks of morbidity in an elderly population. A trial of conservative care is recommended in most cases, but there are presently no randomized controlled studies in the literature comparing surgical versus conservative management, or evaluating the effectiveness of any specific conservative treatment approach. The existing literature has further been criticized for having poorly defined outcome measures. The assessment of treatment outcomes should be multifactorial, including measures of pathoanatomy and impairments, as well as patient-centered measures such as level of disability, patient expectations, and satisfaction. The present level of understanding of lumbar spinal stenosis is deficient in many areas, including differential diagnosis, treatment, and outcome assessment. Future research should address these deficits to improve the management of patients with this condition.  相似文献   

9.
Temperature-sensitive (ts) mutant E/1/3 of Salmonella enteritidis was selected to evaluate its capacity to induce protective responses after peroral (p.o.) or intragastric (i.g.) inoculation to mice. This ts mutant of coasting phenotype was detected in Peyer's patches until day 4, and in spleen by days 3 and 4 after the mice were inoculated by the p.o. route with 10(10) colony forming units. Peroral immunization induced significant protection from oral challenge with 240 LD50 of the wild-type (wt) strain. Higher protection was achieved when the animals were boosted intraperitoneally after p.o. immunization. Intragastric inoculation with the same dose of the ts mutant increased both the level of protection, and colonization and persistence of the micro-organism in Peyer's patches and spleen. Immunization with a single i.g. inoculation induced 70% protection from p.o. challenge of the animals with the wt S. enteritidis. Two i.g. immunizations with E/1/3 raised the level of protection to 90%. Specific IgG, IgM and IgA antibodies, measured in plasma using a micro-ELISA method, were detected after i.g. immunization with ts mutant E/1/3. In addition, specific antibody-secreting cells were detected by means of an ELISPOT assay in spleen and mesenteric nodes of mice immunized with the ts mutant.  相似文献   

10.
This review of current literature on the relationship between unemployment and health covers time-series studies and critiques of this approach; micro-level studies of plant closures, which have yet to provide convincing data; and various studies dealing with mortality rates, physical health, mental health, women, children and families, and youth. At particular risk are youth, the economically marginal, and middle-age men. The most common disorders documented are emotional and cardiopulmonary disease. The key to the relationship between ill-health and unemployment may lie in the emerging epidemiological literature relating health status to social hierarchy. The article concludes with suggestions as to how current knowledge on the pathogenicity of unemployment may be of use to health policy planners on issues such as guaranteed annual incomes.  相似文献   

11.
12.
13.
Vocal fold scarring: current concepts and management   总被引:1,自引:0,他引:1  
Scarring of the vocal folds can occur as the result of blunt laryngeal trauma or, more commonly, as the result of surgical, iatrogenic injury after excision or removal of vocal fold lesions. The scarring results in replacement of healthy tissue by fibrous tissue and can irrevocably alter vocal fold function and lead to a decreased or absent vocal fold mucosal wave. The assessment and treatment of persistent dysphonia in patients with vocal fold scarring presents both diagnostic and therapeutic challenges to the voice treatment team. The common causes of vocal fold scarring are described, and prevention of vocal fold injury during removal of vocal fold lesions is stressed. The anatomic and histologic basis for the subsequent alterations in voice production and contemporary modalities for clinical and objective assessment will be discussed. Treatment options will be reviewed, including nonsurgical treatment and voice therapy, collagen injection, fat augmentation, endoscopic laryngoplasty, and Silastic medialization.  相似文献   

14.
15.
Etiology and pathogenesis of preeclampsia: current concepts   总被引:3,自引:0,他引:3  
The etiology of preeclampsia is unknown. At present, 4 hypotheses are the subject of extensive investigation, as follows: (1) Placental ischemia-Increased trophoblast deportation, as a consequence of ischemia, may inflict endothelial cell dysfunction. (2) Very low-density lipoprotein versus toxicity-preventing activity-In compensation for increased energy demand during pregnancy, nonesterified fatty acids are mobilized. In women with low albumin concentrations, transporting extra nonesterified fatty acids from adipose tissues to the liver is likely to reduce albumin's antitoxic activity to a point at which very-low density lipoprotein toxicity is expressed. (3) Immune maladaptation-Interaction between decidual leukocytes and invading cytotrophoblast cells is essential for normal trophoblast invasion and development. Immune maladaptation may cause shallow invasion of spiral arteries by endovascular cytotrophoblast cells and endothelial cell dysfunction mediated by an increased decidual release of cytokines, proteolytic enzymes, and free radical species. (4) Genetic imprinting-Development of preeclampsia-eclampsia may be based on a single recessive gene or a dominant gene with incomplete penetrance. Penetrance may be dependent on fetal genotype. The possibility of genetic imprinting should be considered in future genetic investigations of preeclampsia.  相似文献   

16.
Dramatic advances in replantation and microsurgery have somewhat altered the criteria we use in selecting patients to be candidates for upper extremity replantation surgery. We suggest that contraindications for such replantation are: presence of associated life-threatening injuries; serious anesthetic risk; preexisting medical or psychiatric problems; previous injury or disease of the amputated part; warm ischemic time greater than 6-8 hours for extremities or greater than 10-12 hours for digits; and single-digit amputations (except thumb, for grasp). Replantation is feasible when: amputated part is properly preserved; injury type is sharp amputation, mild to moderate crush, or selected avulsion, and amputation is proximal to the DIP joint. Careful preservation of the amputated part, not in dry ice, is mandatory. On an individual basis, the decision to attempt replantation rests on the prediction that the patient may have better function with such surgery than with a prosthesis.  相似文献   

17.
During percutaneous coronary revascularization, intracoronary stents are effective in the treatment of abrupt vessel closure and improvement of suboptimal angioplasty results, and compared to balloon angioplasty, they reduce stenosis recurrence. Opposing these benefits, subacute thrombosis of stents is associated with a substantial increase in periprocedural morbidity and mortality. To review factors associated with stent thrombosis and to study the impact of evolving procedural techniques on the incidence of stent thrombosis, we reviewed all English articles from MEDLINE (1988 to 1995) with key words "stent" and "thrombosis." Stent registry data and recent abstracts from scientific meetings were also reviewed. Factors related to the clinical setting, the lesion, the stent and the procedural technique that affect the risk of stent thrombosis were identified. Sixty clinical studies were reviewed and include 7,914 patients receiving intracoronary stents. Studies were separated into those reporting stents placed emergently or electively without adjunct high-pressure balloon inflations, stents placed in saphenous vein graft conduits, and stents placed with high-pressure balloon inflations but without subsequent oral anticoagulants. Overall, subacute thrombosis was substantially higher in stents placed emergently (10.1%) compared to those placed electively (4.3%). Among contemporary trials employing high-pressure balloon inflations, the rate of stent thrombosis appears markedly lower (1.3%) despite reduced postprocedural anticoagulation. Taken together, these studies suggest factors associated with a heightened risk of stent thrombosis, many of which can be avoided with proper case selection and contemporary techniques.  相似文献   

18.
OBJECTIVE: Leptin is the product of ob gene shown to regulate body fat in mice. It is produced by human adipose tissue as well, but its physiological functions in man are not known. We explored if there is a relationship in obese humans with serum leptin and energy and fuel metabolism. DESIGN: Cross-sectional study including 45 obese (10 men, 35 women; age and body mass index: 42 +/- 7 y and 35.1 +/- 3.6 kg/m2, respectively). MEASUREMENTS: Food intake by a four-day-food record, blood samples for serum leptin concentrations and resting energy expenditure by indirect calorimetry. RESULTS: Leptin concentrations showed an inverse association (adjusted for fat mass, age and sex) with resting energy expenditure, respiratory quotient and carbohydrate oxidation rate (r = -0.324, P < 0.05; r = -0.420, P < 0.01; r = 0.478, P = < 0.01, respectively), and interestingly, also with dietary fat intake (unadjusted r = -0.30, P < 0.05). Especially, leptin concentrations were elevated in those with low resting energy expenditure and respiratory quotient (below the median). CONCLUSION: Serum leptin concentrations in obese subjects showed an inverse association with resting energy expenditure, respiratory quotient and carbohydrate oxidation rate. The physiological significance of these associations is unclear at the moment but could indicate that obese subjects show resistance to the actions of leptin also outside the brain in terms of regulating metabolic rate and fuel metabolism.  相似文献   

19.
The recent advances in the treatment of Parkinson's disease have made for significant improvements in the quality of life and mortality rate of those who suffer from this neurodegenerative disease. At the same time, the number of options and the complexity of multi-drug regimens have posed a great challenge for the clinician caring for the patient with Parkinson's disease. Though there are still many questions to be answered in regard to the potential neuroprotective effects of several medications, a few general rational treatment plans can be outlined. In patients requiring treatment in the early stages of the disease, especially with a predominance of tremor, anticholinergics or amantadine should be considered initially. At this point, it would be reasonable to add selegiline for both therapeutic and possible neuroprotective effects. As a patient becomes more affected by the disease and additional therapy is necessary, starting either a dopamine agonist or levodopa would be a rational choice. Continuation of selegiline and, possibly, amantadine for neuroprotective reasons should be contemplated. Titration in levodopa therapy (with controlled-release or standard levodopa) to higher levels should prompt addition of a dopamine receptor agonist if one has not been started previously. Conversely, if a patient is receiving only a dopamine receptor agonist and is becoming progressively disabled, levodopa should be added to the regimen. Fluctuations in motor abilities may be improved further by the use of a COMT inhibitor. Patients with uncontrollable motor fluctuations should be considered for surgery. Undoubtedly, the coming years will bring more treatment options and more evidence on which sequences and combinations of therapies are the most beneficial. Differences in efficacy and adverse effects for each patient must be taken into consideration when outlining and carrying out a treatment plan. By using a rational approach to the treatment of Parkinson's disease, with the above guidelines in mind, the patient should be able to enjoy a good quality of life and level of function for many years.  相似文献   

20.
We describe five cases of Q fever in pregnant women that were diagnosed during the last 3 years in the town of Martigues in Southern France. Analysis of our cases and the 18 other published cases shows that Q fever is a significant cause of morbidity and mortality in pregnancy. The disease may present as an acute or chronic infection and can be reactivated during subsequent pregnancies, as is seen with other mammals. In Martigues, Q fever is present in at least one per 540 pregnancies and constitutes the most significant public health problem related to intrauterine infections.  相似文献   

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