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21.
Comparative genomic hybridization on a microarray (microarray-CGH) allows to detect genomic chromosome imbalances. In order to assess its value to detect small chromosome imbalances observed in a clinical setting, using a DNA chip available commercially (Spectral Genomics, Houston, Texas, USA), we studied the DNA of 9 patients carrying a well characterized chromosome imbalance and the DNA of 11 patients where cytogenetic techniques such as high resolution banding karyotype, FISH using subtelomeric probes and comparative genomic hybridization on metaphase chromosomes conclude to a normal and/or balanced karyotype. A result was obtained for 19/20 patients. Failure of hybridization was observed for one patient. For all the other cases the sex of patients was correctly identified. Microarray-CGH was able to correctly diagnose the chromosome imbalance in 6/8 patients carrying such a defect i.e 9/11 imbalances (deletion or duplication) were detected. No chromosome imbalance was observed in 11 patients considered normal and/or balanced using cytogenetic techniques. Several clones were found to be polymorphic and required FISH studies to eliminate duplication or deletion. In conclusion, we think that this commercially available DNA chip might be useful to screen for chromosome imbalances. However, technical improvements are still necessary before using it in a clinical setting. Also, further studies are necessary to assess its sensitivity and specificity.  相似文献   
22.
The complete genetic information for the neuraminidase (NA) gene of influenza virus A/Bangkok/1/79 has been cloned by in vitro synthesis of dsDNA, insertion into pBR322 plasmid, and transformation of Escherichia coli. The nucleotide sequence of the NA gene has been determined by the Maxam and Gilbert method. It is 1466 nucleotides long and contains a single open reading frame with a coding capacity for 469 amino acids. When compared to the NA genes of the N2 strains A/Victoria/3/75, A/Udorn/72, A/NT/60/68, and A/RI/5-/57, 90% of the nucleotide positions and 87% of the amino acid positions remained invariant. Forty-two nucleotide changes and 14 amino acid changes accumulated in the period 1975-1979, but the general structure of the protein appeared to remain constant.  相似文献   
23.
ObjectiveSensory deficits are important risk factors for delirium but have been investigated in single-center studies and single clinical settings. This multicenter study aims to evaluate the association between hearing and visual impairment or bi-sensory impairment (visual and hearing impairment) and delirium.DesignCross-sectional study nested in the 2017 “Delirium Day” project.Setting and ParticipantsPatients 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes, and hospices in Italy.MethodsDelirium was assessed with the 4AT (a short tool for delirium assessment) and sensory deficits with a clinical evaluation. We assessed the association between delirium, hearing and visual impairment in multivariable logistic regression models, adjusting for: Model 1, we included predisposing factors for delirium (ie, dementia, weight loss and autonomy in the activities of daily living); Model 2, we added to Model 1 variables, which could be considered precipitating factors for delirium (ie, psychoactive drugs and urinary catheters).ResultsA total of 3038 patients were included; delirium prevalence was 25%. Patients with delirium had a higher prevalence of hearing impairment (30.5% vs 18%; P < .001), visual impairment (24.2% vs 15.7%; P < .01) and bi-sensory impairment (16.2% vs 7.5%) compared with those without delirium. In the multivariable logistic regression analysis, the presence of bi-sensory impairment was associated with delirium in Model 1 [odds ratio (OR) 1.5, confidence interval (CI) 1.2–2.1; P = .00] and in Model 2 (OR 1.4; CI 1.1–1.9; P = .02), whereas the presence of visual and hearing impairment alone was not associated with delirium either in Model 1 (OR 0.8; CI 0.6–1.2, P = .36; OR 1.1; CI 0.8–1.4; P = .42) or in Model 2 (OR 0.8, CI 0.6–1.2, P = .27; OR 1.1, CI 0.8–1.4, P = .63).Conclusions and implicationsOur findings support the importance of routine screening and specific interventions by a multidisciplinary team to implement optimal management of sensory impairments and hence prevention and the management of the patients with delirium.  相似文献   
24.
AimsTo validate a translated and culturally adapted version of the Morisky Medication Adherence Scale for use in Spanish population, and to examine the psychometric properties of this scale in patients with type 2 diabetes mellitus in Spain.DesignThis cross-sectional study was conducted in a single university hospital in Spain. Patients diagnosed with type 2 diabetes mellitus at least 1 year before inclusion, being treated with anti-diabetic medication were included.InterventionWe used the Spanish version of the scale to measure treatment adherence.Principal measurementsthree level categorical scale is broken down into low adherence (score of <6), medium adherence (score of 6 to <8) and high adherence (score of 8). To validate the questionnaire, we measured internal consistency through Cronbach's α, confirmed construct validity through an exploratory principal component analysis and assessed test–retest reliability.Results232 patients met the inclusion criteria. The Cronbach's α coefficient was 0.40 (95% CI 0.28–0.52). The exploratory principal component analysis showed three components. The intraclass correlation coefficient was 0.718 (95% CI 0.564–0.823).Conclusionsthe Spanish version of the Morisky Medication Adherence scale showed low internal consistency, the exploratory factor analysis identified three dimensions, and the test–retest reliability was acceptable, therefore, psychometric properties of MMAS-8 are not suitable for measuring medication adherence in type 2 diabetes mellitus patients from Spain.  相似文献   
25.
The capability of the methoxy-substituted 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3 or Edelfosine) and the two aza-alkylphospholipids BN 52205 and BN 52211 to bind to the PAF receptor was analysed in rabbit platelet membranes. Ether phospholipid concentrations were tested between 10(-5) M and 10(-11) M. The results indicate that ether phospholipids are not able to bind to the PAF receptor and do not prevent PAF binding to its receptor. Moreover, the cytotoxic effect of three potent PAF antagonists, BN 52021, BN 50730 and BN 50739, were analysed in HL60 promyelocytic cells. These cells were pre-and co-treated with PAF antagonists and ether phospholipids. The data show that the three PAF antagonists failed to counteract the activity of ET-18-OCH3, BN 52205 and BN 52211 thus demonstrating that the cytotoxic effect of these new anti-neoplastic drugs is not mediated by the PAF receptor.  相似文献   
26.
Stroke mortality rates in Spain are one of the highest in all of Europe. At the same time, the Murcia region (south-east Spain) shows, for both genders, the highest age-adjusted stroke mortality rates in all of Spain. The earliest available hypertension figure estimations for this area go back to 1981, when a high prevalence combined with an almost nonexistent control was detected. One decade later, updated prevalence estimations of hypertension are presented jointly with their degree of control and their association with other risk factors based on the results of a prevalence survey in a random population sample (n = 3,091). Arterial blood pressure was measured following the MONICA protocol, maintaining a tight quality control on between and within-observer variability. As hypertensive was considered as any person with systolic blood pressure (SBP) 140 mmHg or with diastolic blood pressure (DBP) 90 mmHg or with antihypertensive pharmacological treatment. Detected prevalence rises to 32.3% (CI 95%: 29.1%–35.5%) among males and to 23.7% (CI 95%: 21.4%– 26%) among females, maintaining its level regarding figures observed back in 1981. However, its control has been increased, especially among hypertensive women [from less than 5% in 1981 to 35% (95% CI: 32%–37.8%) at present]. Hypertension is strongly associated to hipercholesterolemia, overweight, obesity and diabetes (p < 0.01). On the contrary, it shows an opposite association with current smoking, higher educational level and leisure time physical activity (p < 0.01). The highest educational level was associated with better hypertension treatment and control. In summary, while hypertension prevalence is stabilized in our population, its control has improved in a measurable but still insufficient way. These results are in accordance with a decreasing trend in stroke mortality registered in the Murcia Region along the last decade.  相似文献   
27.
By in situ hybridization we studied the expression patterns of Msx and Hoxd genes during the late development of the chick leg autopodium (foot) and compared them to patterns during the experimental development of interdigital extra digits. Extra digits are induced in the third interdigital space after various experimental manipulations, such as transient isolation of the interdigit, or removal of the interdigital marginal ectoderm and mesoderm. Msx1 and Msx2 are normally expressed in the interdigital tissue programmed to die. Our experiment changes the fate of the interdigital tissue from cell death to chondrogenesis and provides a good model for studying Msx involvement in defining areas of programmed cell death. Among the proposed roles for Hoxd genes is their involvement in the specification of digit identity early in development. The induction of extra digits allows us to examine whether this new morphogenetic commitment of the interdigital tissue involves changes in the domains of expression of Hoxd genes. Our results show that extra digits develop without a previous modification of the normal pattern of expression of Msx or Hoxd genes. This observation does not support the correlation between the expression of Msx genes and programmed cell death and suggests a role for these genes in maintaining the interdigital tissue in an undifferentiated state. Our results show that an increased number of digits can be formed without modifications in the pattern of expression of the 5-located Hoxd genes and suggest the existence of latent or residual digit organization mechanisms past the time when digits are normally determined, independent of Hoxd gene expression.  相似文献   
28.
The objective was to determine whether the use of intermediate echo times (135 ms) in proton magnetic resonance spectroscopy (1H-MRS) detects a homogenous pattern in progressive multifocal leukoencephalopathy (PML) in HIV-1 infected people, and to confirm the results of previous studies. Six patients infected with HIV-1, with PML established by biopsy, and six healthy age and sex matched volunteers were evaluated to define their spectroscopic pattern. 1H-MRS spectra performed at 1.5 T were obtained with the STEAM sequence: TE/TM/TR, 20 ms/13.7 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (STEAM-20) and with the PRESS sequence; TE/TR, 135 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (PRESS-135). A single voxel was placed on the lesions and on the parieto-occipital white matter of controls. The peaks of N-acetylaspartate (NAA), choline (Cho), myoinositol (mI), lactate, and lipids were considered, and the results were expressed using creatine as reference. Spectra of PML lesions were characterised by significantly reduced NAA, lactate presence, and by significantly increased Cho and lipids compared with control group values. These results indicate that 1H-MRS detects a homogenous pattern in PML lesions. Recent studies, together with this, suggest that 1H-MRS may help in the diagnostic approach to patients with suspected PML lesions associated with AIDS.  相似文献   
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