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81.
82.
Therapy-related acute myeloid leukemia (t-AML) characterized by the t(9;11)(p22;q23) translocation is one of the most frequent secondary malignancies. The timing of the initiation of translocation and of development of the malignant t(9;11) clone during chemotherapy is presently unknown. In the present study, we backtracked bone marrow samples from three children during treatment for acute lymphoblastic leukemia (ALL). Two patients developed a t(9;11)-positive t-AML 19 and 30 months after therapy start, whereas the third patient, diagnosed with a rare t(9;11)-positive ALL, suffered from an ALL relapse 23 months after initial diagnosis. The genomic MLL-MLLT3 (MLL-AF9) fusion site was amplified by a multiplex, nested long-range PCR and used as a clonal marker for quantification of the MLL-MLLT3-positive cells during chemotherapy. The t(9;11)-positive clone was detectable 13 and 18 months after therapy start in both t-AML cases, which was 6-12 months before clinical diagnosis of the secondary malignancy. In the t(9;11)-positive ALL patient, the identical leukemic clone reoccurred during maintenance therapy after a short molecular remission, 8 months before clinically overt ALL relapse. The time course and characteristics of the genomic breakpoints in the present t-AML cases support the hypothesis of translocation formation as a result of defective breakage repair after topoisomerase II cleavage.  相似文献   
83.
Although little is known about the neuroanatomical basis of skin conductance orienting in intact normal humans, the limited literature on animals and humans with neurological and clinical disorders implicate prefrontal, temporal/amygdala, and pons brain areas in mediating skin conductance orienting. This study relates area of these structures using magnetic resonance imaging techniques to skin conductance orienting responses in 17 normal humans in order to test hypotheses that larger area of these excitatory structures will be associated with more orienting responses. Left and right hand skin conductance orienting was significantly associated with left and right prefrontal area (r = .44-.60), area of the pons (r = .43-.54), and left but not right temporal/amygdala area (r = .47-.53). No relationships were observed with areas thought to be unrelated to skin conductance activity (cerebellum, nonfrontal cortical area), medial prefrontal cortex, or the third ventricle. This appears to be the first study relating brain structure to skin conductance orienting in intact normal humans. Although preliminary at the present time, these results implicate prefrontal, pons, and temporal/amygdala areas in the mediation of skin conductance orienting in normal humans.  相似文献   
84.
Screening women for sexually transmitted diseases (STD) in nonclinic settings is highly desirable because many infections are asymptomatic. This is especially true for military women, for whom logistical, social, and other job-related obstacles present barriers to accessing medical care. We assessed the accuracy of intravaginal swabs transported by mail in a wet versus a dry state for PCR (Amplicor CT/NG test) detection of chlamydia and gonorrhea infections in a cross-sectional study of 793 active-duty military women attending an STD clinic. PCR tests of vaginal swabs (wet and dry) were compared to local clinical methods used on cervical swabs. Standard wet vaginal swab PCR testing detected more chlamydia (11.6%) than cervical enzyme immunoassay (9.3%). For detection of chlamydia using wet swabs, the sensitivity and specificity compared with adjudicated true positives were 94.6% (87 of 92) and 99.3% (696 of 701), respectively. Comparing dry swabs to true-positives for chlamydia, the sensitivity was 91.3% (84 of 92) and the specificity was 99.3% (696 of 701). Standard wet vaginal swab PCR detected more gonorrhea (3.3%) than routine cervical culture (2.1%). The sensitivity and specificity of PCR testing of wet swabs compared to true-positives (infected patients) were 96.3% (26 of 27) and 98.2% (752 of 766) for gonorrhea, respectively. For gonorrhea, the sensitivity and specificity of dry swabs compared to true-positives (infected patients) were 88.9% (24 of 27) and 98.3% (753 of 766), respectively. PCR testing of wet and dry transported intravaginal swabs to detect chlamydia and gonorrhea infections was an accurate diagnostic method for military women.  相似文献   
85.
Common variable immunodeficiency (CVID) is associated with autoimmunity, most commonly immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA). In a retrospective chart review of 326 CVID patients, 35 (11%) patients had a history of autoimmune hematologic disease. Fifteen patients had ITP, 9 had AIHA, and 11 had Evans syndrome (both ITP and AIHA). The age at diagnosis for CVID ranged from 5 to 66 years and for autoimmunity, from 2 to 66 years. There were 16 males and 19 females. Nineteen patients (54%) had the first episode of thrombocytopenia or hemolytic anemia prior to the diagnosis of immunodeficiency, 11 (32%) were diagnosed concurrently, and 5 (14%) developed one or both of these autoimmune diseases following the diagnosis of CVID. Eight patients were known to have granulomatous changes in one or more organs. Treatments for autoimmunity included corticosteroids, anti-Rh immunoglobulin, and intravenous immunoglobulin; 11 patients underwent splenectomy. While 5 patients had recurrences of autoimmune hemolytic disease while receiving maintenance intravenous immunoglobulin, most episodes occurred for subjects not yet on this therapy (P < 0.0001). Most patients with frequent infections and hematologic autoimmunity should be evaluated for CVID.  相似文献   
86.
Neurons in trigeminal and geniculate ganglia extend neurites that share contiguous target tissue fields in the fungiform papillae and taste buds of the mammalian tongue and thereby have principal roles in lingual somatosensation and gustation. Although functional differentiation of these neurons is central to formation of lingual sensory circuits, there is little known about electrophysiological properties of developing trigeminal and geniculate ganglia or the extrinsic factors that might regulate neural development. We used whole cell recordings from embryonic day 16 rat ganglia, maintained in culture as explants for 3-10 days with neurotrophin support to characterize basic properties of trigeminal and geniculate neurons over time in vitro and in comparison to each other. Each ganglion was cultured with the neurotrophin that supports maximal neuron survival and that would be encountered by growing neurites at highest concentration in target fields. Resting membrane potential and time constant did not alter over days in culture, whereas membrane resistance decreased and capacitance increased in association with small increases in trigeminal and geniculate soma size. Small gradual differences in action potential properties were observed for both ganglion types, including an increase in threshold current to elicit an action potential and a decrease in duration and increase in rise and fall slopes so that action potentials became shorter and sharper with time in culture. Using a period of 5-8 days in culture when neural properties are generally stable, we compared trigeminal and geniculate ganglia and revealed major differences between these embryonic ganglia in passive membrane and action potential characteristics. Geniculate neurons had lower resting membrane potential and higher input resistance and smaller, shorter, and sharper action potentials with lower thresholds than trigeminal neurons. Whereas all trigeminal neurons produced a single action potential at threshold depolarization, 35% of geniculate neurons fired repetitively. Furthermore, all trigeminal neurons produced TTX-resistant action potentials, but geniculate action potentials were abolished in the presence of low concentrations of TTX. Both trigeminal and geniculate neurons had inflections on the falling phase of the action potential that were reduced in the presence of various pharmacological blockers of calcium channel activation. Use of nifedipine, omega-conotoxin-MVIIA and GVIA, and omega-agatoxin-TK indicated that currents through L-, N-, and P/Q- type calcium channels participate in the action potential inflection in embryonic trigeminal and geniculate neurons. The data on passive membrane, action potential, and ion channel characteristics demonstrate clear differences between trigeminal and geniculate ganglion neurons at an embryonic stage when target tissues are innervated but receptor organs have not developed or are still immature. Therefore these electrophysiological distinctions between embryonic ganglia are present before neural activity from differentiated receptive fields can influence functional phenotype.  相似文献   
87.
Endometriosis is subsequent to the ability of endometrial glands to invade normal tissues. Matrix metalloproteinases (MMPs)—enzymes that mediate normal tissue turnover, including endometrial breakdown during menstruation—appear to be involved in this invasive process. Here, we examined the immunohistochemical expression of MMP-2, MMP-3, MMP-11, tissue inhibitor metalloproteinase (TIMP)-1 and TIMP-2 in endometrium from women with (n=9) or without endometriosis (n=18) in comparison with peritoneal (n=20), ovarian (n=20) and colorectal endometriosis (n=20). Women with endometriosis showed decreased endometrial MMP-2 expression compared with women without endometriosis (mean±SD positive cells: 24.3±28.3% and 69.3±12.1%), together with loss of MMP-3 expression (0 versus 17.5%±20.2). MMP-11, TIMP-1 and TIMP-2 expression was similar in the two groups. Endometrial MMP-2, -3 and -11 expression and TIMP-1 and -2 expression were similar in women with endometriosis and in those with peritoneal endometriosis. MMP-2, -3 and -11 expression was higher in colorectal endometriosis than in ovarian and peritoneal endometriosis. TIMP-2 expression was lower in colorectal endometriosis (P=0.0002) and ovarian endometriotic cysts (P=0.003) than in peritoneal endometriosis. TIMP-1 expression did not vary according to the location of endometriotic lesions. These results suggest that MMP-2 and -3 and TIMP-2 may be involved in the pathogenesis of endometriosis. Interestingly, MMP-2 and -3 overexpression was related to the infiltrative nature of endometriotic lesions, with possible sequential expression from peritoneal to colorectal endometriosis.  相似文献   
88.
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.  相似文献   
89.
Women who take folic acid in the periconceptional period greatly reduce their chances of having a child with a neural tube defect (NTD). Using multivitamins may also reduce the risk of having a child with an omphalocele. In this study, we tested single nucleotide polymorphisms in folate-related enzyme genes for association with omphalocele. Polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methylenetetrahydrofolate dehydrogenase (MTHFD1), the reduced folate carrier (SLC19A1), and transcobalamin II (TCN2) were examined in 25 children with euploid omphalocele and 59 matched controls. Omphalocele cases were significantly more likely to carry the T allele of MTHFR 677C-->T, a known risk factor for NTDs (odds ratio 3.50, 95% confidence interval 1.07-11.47, P=0.035). The MTHFD1 R653Q, SLC19A1 R27H, and TCN2 P259R polymorphisms showed no significant association with omphalocele. In this small study, the thermolabile variant of MTHFR, 677C-->T, was associated with an increased risk for omphalocele. This variant causes reduced enzyme activity, thus suggesting a mechanism by which multivitamins with folic acid might prevent omphalocele. Additional investigation is required.  相似文献   
90.
Zusammenfassung Die Aktion «Gesunde Ernährung» in der Gemeinde-wurde vom Gesundheitsdepartement des Kanton St. Gallen unter der Leitung des kantonalen Präventivmediziners gemeinsam mit den interessierten Gemeinden geplant, koordiniert und durchgeführt.Im Zentrum der Aktion standen gemeindeeigene, individuell gestaltete Aktivitäten von Vereinen, Schulen und des lokalen Gewerbes. Das Gesundheitsdepartement ergänzte die Aktion mit einer Wanderausstellung über Ernährungsfragen, begleitet von einer Ernährungsberaterin. Der Aufbau der Ausstellung erfolgte nach den 10 goldenen Regeln der gesunden Ernährung.Diese Aktion stellt ein konkretes Beispiel der Arbeitsteilung zwischen Kanton und Gemeinde in der Gesundheitsvorsorge dar. Das Beispiel dieser einmaligen Aktion soll Behörden, Vereinen und Einzelpersonen Wege und Methoden aufzeigen, Anliegen der Gesundheitsvorsorge auf längerfristiger Basis in der Gemeinde zu planen.
Healthy Nutrition an experience of health promotion in the county of St. Gall
Summary The drive Healthy Nutrition in communities was planned, co-ordinated und carried out as a joint action by the Health Department of the County of St. Gall, and 37 communities interested in the idea. The drive centred around the activities of the community itself, individuals, clubs, schools and local industry.The County Health Department supplemented the activity with a travelling exhibition about nutrition problems, attended by an advisor to answer questions. The build-up of the exhibition followed the 10 Golden Rules of sound nutrition.This drive was an excellent example of how health-promotion programms can be shared by county und community.This unique action should set an example to other authorities, clubs, and individuals, and show the ways and means needed to provide long-term planning for health promotion in the community.

«Alimentation saine»: le programme du canton de St-Gall
Résumé Un programme «Alimentation saine» a été planifié, coordonné et réalisé en étroite collaboration entre le Service cantonal de médecine préventive et les communes intéressées.Les activités développées par les sociétés locales, les écoles et les commerÇants ont été les éléments essentiels du programme. Le canton a, quant à lui, engagé une diététicienne et mis un bus à disposition ce qui a permis d'organiser une exposition itinérante conÇue selon les 10 règles d'or de l'alimentation saine.Ce programme est une expérience de collaboration entre le canton et les communes pour la promotion de la santé. Il devrait servir d'exemple aux autorités, sociétés locales et individus qui désirent répondre au défi de la promotion de la santé.
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