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21.
The cause of sudden infant death syndrome (SIDS) is unknown. Sleep-related impairment of respiratory control and arousal are postulated; hyperdopaminergic and hyposerotonergic dysfunction may contribute to events leading to infant apnea and SIDS. Psychosocial adversity and impulsive and compulsive behaviours characterize some families of SIDS victims. Tourette syndrome (TS) is a common hereditary neurobehavioral disorder characterized by the frequent presence of impulsive and compulsive behaviors. Sleep disorders are common and include sleep apnea and abnormal arousal. Hyperdopaminergic and hyposerotonergic abnormalities are postulated to contribute to the pathophyusiology of the disorder. The following is a report of the presence of incidents of infant apnea and SIDS in families in which TS was present. In an additional TS family, a child had obstructive sleep apnea syndrome (OSAS). Results of a preliminary survey suggest that TS gene carriers are at increased risk of life-threatening apneas of infancy and that the prevalence of SIDS in such families may be 2 to 5 times the prevalence in the general population. The presence in some pedigrees of sleep apnea in children and adults suggest that in some instances disorders of sleep-related ventilatory control and arousal occurring throughout the life-span share common pathophysiological mechanisms. © 1993 Wiley-Liss, Inc. 相似文献
22.
S. Finegold P. Summanen S. Hunt Gerardo E. Baron 《European journal of clinical microbiology & infectious diseases》1992,11(11):1058-1063
Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, urease-positive, bile-resistant, catalase-positive bacillus, originally recovered from infections in patients with gangrenous and perforated appendicitis. Additional isolations from clinical specimens, including pleural fluid, joint fluid, blood and pus from a scrotal abscess, mandibular osteomyelitis and axillary hidradenitis suppurativa are described here.Bilophila is found as normal flora in feces and, occasionally, in saliva and in the vagina. Isolates from humans are usually -lactamase positive and therefore resistant to certain -lactam antibiotics. Two percent of strains are also resistant to clindamycin. 相似文献
23.
A complex chromosome rearrangement with 10 breakpoints: tentative assignment of the locus for Williams syndrome to 4q33----q35.1. 下载免费PDF全文
R Tupler P Maraschio A Gerardo R Mainieri G Lanzi L Tiepolo 《Journal of medical genetics》1992,29(4):253-255
An unbalanced complex chromosome rearrangement with 10 breakpoints resulting in four derivative chromosomes (1, 2, 4, and 11) was found in a girl with severe phenotypic abnormalities, many of which are characteristic of Williams syndrome. The patient was monosomic for the region 4q33----q35.1 and thus the mapping of the syndrome could tentatively be restricted to this region. 相似文献
24.
Gerardo Martinez Carmen Mijangos Jos-Luis Millan Donald L. Gerrard William F. Maddams 《Macromolecular chemistry and physics.》1984,185(7):1277-1284
The products resulting from the reaction of PVC with sodium benzenethiolate were degraded to 0,3% at 180°C in the solid state and at 160°C in solution in trichlorobenzene. The polyene distribution of the polymers after degradation was studied by both UV-visible and resonance Raman spectroscopies, as a function of the degree of substitution. The results show that there are two types of behaviour: that of the PVC sample prior to the substitution reaction together with the samples modified up to a definite degree of substitution which depends on the starting isotactic content, and that of samples with higher degrees of substitution. The former group exhibits not only a steady improvement in thermal stability but also a preferential formation of polyenes of 7 – 9 double bonds whose concentration decreases with increasing degree of substitution. Conversely, for the second group of samples the thermal stability decreases with the degree of substitution and no specific absorption bands are observed. On the basis of earlier work on the selective substitution of the isotactic GTTG and heterotactic TTTG triads during the first stage of the reaction, the present results show that the bands at 393, 416, and 437 nm are related to specific polyenes which result from initiation by the above quoted conformations in PVC, a conclusion for which confirmatory evidence was obtained by resonance Raman spectroscopic examination of the samples. There is, therefore, clear evidence for the occurrence of two distinct degradation mechanisms, one involving initiation by the unstable triad conformations and the other via random initiation at stable and normal structures. To this may be added the initiation by defect structures, which have been extensively documented in the literature. 相似文献
25.
Rosa C. Villegas-Valle Unhee Lim Gertraud Maskarinec Adrian A. Franke Thomas Ernst Bo Fan Gerardo Álvarez-Hernández Maria del Carmen Candia-Plata Rolando Giovanni Díaz-Zavala Lynne R. Wilkens Kristine R. Monroe Mauro E. Valencia Loïc Le Marchand John A. Shepherd 《Obesity research & clinical practice》2021,15(3):227-234
ObjectiveTo determine if visceral adipose tissue (VAT) area measured through MRI can be used opportunistically to assess the presence of cardiometabolic risk factors and compare its performance to simpler adiposity measures.MethodsA cross-sectional analysis was carried out on a subset of 1683 participants (856 women) from the Adiposity Phenotype Study (mean age = 69.2y; range 59.9–77.4). The association of total VAT area (sum of four cross sections, L1–L2, L2–L3, L3–L4, L4–L5) and each location, as well as BMI and body fat % (per SD) with the metabolic syndrome (MetSx) or its components was evaluated through logistic regression analysis.ResultsTotal VAT can be accurately predicted using all sites evaluated (R2 range = 0.82?0.96). In men, VAT did not show a superior association to MetSx compared to BMI in men. However, in women, VAT was consistently superior to BMI and body fat % in its association to MetSx, independent of ethnicity [odds ratio for BMI, body fat %and total VAT area = 2.25 (95% CI: 1.93–2.62); 1.66 (95% CI: 1.36–2.03); 6.20 (95% CI: 4.69–8.21) respectively in all women]. Ethnic-specific odds ratios to MetSx in women ranged from 5.38 to 8.63 for total VAT area and 2.12–4.08 for BMI.ConclusionTotal VAT area can be accurately predicted from individual VAT regions in men and women and offers superior association to BMI for MetSx in women but not in men for five ethnicities. Therefore, opportunistic screening for elevated VAT area in women may be warranted across multiple ethnic groups. 相似文献
26.
Aránzazu Caballero-Marcos Magdalena Salcedo Roberto Alonso-Fernández Manuel Rodríguez-Perálvarez María Olmedo Javier Graus Morales Valentín Cuervas-Mons Alba Cachero Carmelo Loinaz-Segurola Mercedes Iñarrairaegui Lluís Castells Sonia Pascual Carmen Vinaixa-Aunés Rocío González-Grande Alejandra Otero Santiago Tomé Javier Tejedor-Tejada José María Álamo-Martínez Luisa González-Diéguez Flor Nogueras-Lopez Gerardo Blanco-Fernández Gema Muñoz-Bartolo Francisco Javier Bustamante Emilio Fábrega Mario Romero-Cristóbal Rosa Martin-Mateos Julia Del Rio-Izquierdo Ana Arias-Milla Laura Calatayud Alberto A. Marcacuzco-Quinto Víctor Fernández-Alonso Concepción Gómez-Gavara Jordi Colmenero Patricia Muñoz José A. Pons the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, p < .001) and at 6 months (63.4% vs. 90.1%, p < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (p = .001) and 6 months (p < .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline. 相似文献
27.
Atypical squamous cells. A case-series study of the association between papanicolaou smear results and human papillomavirus DNA genotype. 总被引:3,自引:0,他引:3
J S Rader B A Rosenzweig R Spirtas R Padleckas G Javaheri L Gerardo L A Laimins 《The Journal of reproductive medicine》1991,36(4):291-297
Thirty women with "atypical" squamous cells but not cervical intraepithelial neoplasia (CIN) on their Papanicolaou smears were tested for the presence of human papillomavirus (HPV) with the Southern blot hybridization technique. The Papanicolaou smears were reviewed for the presence of atypical squamous cells according to Patten's criteria. Comparison groups consisted of 30 patients with normal, 29 patients with CIN I and 24 patients with CIN II Papanicolaou smears. Ten of the 30 women (33%) with atypical cells on Papanicolaou smears were positive for HPV DNA as compared to 17% with normal and 59% with CIN I or II Papanicolaou smears. HPV 16 was present in 70-80% of the HPV DNA-positive patients in each Papanicolaou smear group. Concurrent CIN was also identified on colposcopically directed biopsies in 27% of the patients with squamous atypia. Patients with atypical squamous cells on Papanicolaou smears had coexisting HPV infection and CIN in about one-third of the cases. Colposcopy and further follow-up are recommended for such patients. 相似文献
28.
Consuelo Garcia Emma S Calderón-Aranda Gerardo A V Anguiano Baltazar Becerril Lourival D Possani 《Toxicon》2003,41(4):417-427
Three different immunogens from the venom of the Mexican scorpion Centruroides noxius Hoffmann were used to study protective antibody response in mice and rabbits, challenged with toxin Cn2, one of the most abundant toxic peptide of this venom. The immunogens were: Cn5, a crustacean specific toxin; a recombinant protein containing the peptide Cn5 linked to the maltose transporter and a sub-fraction (F.II.5) containing 25 distinct peptides, among which is Cn5. Mice immunized with these three preparations, when directly challenged with Cn2 presented no apparent protection, whereas anti-sera produced in rabbits with these three immunogens were capable of partially neutralizing the effect of Cn2, when injected into naive mice. Cn5 rabbit anti-serum showed a better protective effect on mice, than the rabbit sera obtained against the two other antigens. The subcutaneous route of challenging mice was shown to be better than intraperitoneal injections. Comparative structural analysis of Cn5 with other toxins of this venom showed that our results are important to be taken into consideration, when choosing appropriate immunogens aimed at the production of better anti-venoms or for the rational design of possible vaccines. 相似文献
29.
Francesco Izzo Paolo Marra Gerardo Beneduce Giuseppe Castello Paolo Vallone Vincenzo De Rosa Franco Cremona C Mark Ensor Frederick W Holtsberg John S Bomalaski Mike A Clark Chaan Ng Steven A Curley 《Journal of clinical oncology》2004,22(10):1815-1822
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted. 相似文献
30.
HMGA1 protein overexpression in human breast carcinomas: correlation with ErbB2 expression. 总被引:6,自引:0,他引:6
Gennaro Chiappetta Gerardo Botti Mario Monaco Rosa Pasquinelli Francesca Pentimalli Maurizio Di Bonito Giuseppe D'Aiuto Monica Fedele Rodolfo Iuliano Emiliano A Palmieri Giovanna Maria Pierantoni Vincenzo Giancotti Alfredo Fusco 《Clinical cancer research》2004,10(22):7637-7644
We measured, by immunohistochemistry, HMGA1 protein expression in 212 breast tissue specimens: 6 normal samples, 28 hyperplastic lesions (13 with cellular atypia), 11 fibroadenomas, 10 in situ ductal carcinomas, 144 ductal carcinomas, and 13 lobular carcinomas. HMGA1 was not expressed in normal breast tissue; HMGA1 staining was intense in 40% of hyperplastic lesions with cellular atypia and in 60% of ductal carcinomas and weak in fibroadenomas and in hyperplastic lesions without cellular atypia. Because HMGA1 expression was similar among ductal breast carcinomas with different histologic grading, we evaluated the association between HMGA1 expression and that of other markers of breast carcinoma invasion (estrogen and progesterone receptors, Ki-67 antigen, and ErbB2) in 21 cases of grade 3 breast ductal carcinomas and 7 cases of breast lobular carcinomas. We found that HMGA1 expression tended to be associated only with c-erbB-2 expression (Spearman rho: 0.36; P=0.065). Taken together, these results suggest that HMGA1 expression might be a novel indicator for the diagnosis and prognosis of human breast cancer. 相似文献