The evaluation of agreement on continuous variables by the intraclass correlation coefficient.
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Cardiovascular Diseases↗
Biomedical subjects
J Alonso
Publications and source records attributed to J Alonso.
Endothelin-1 upregulation in the kidney of uninephrectomized spontaneously hypertensive rats and its modification by the angiotensin-converting enzyme inhibitor quinapril.
Endothelin (ET-1) is a potent vasoconstrictor that plays an important role in the control of renal circulation and tubular function. The contribution of this peptide to the pathogenesis of systemic hypertension and renal failure remains largely undefined. In spontaneously hypertensive rats (SHR) uninephrectomized at 20 weeks of age (UNX-SHR) and followed until 45 weeks of age, we determined ET-1 gene expression in renal tissue by reverse transcription-polymerase chain reaction and its localization by in situ hybridization in paraffin-embedded kidney sections. Age-matched SHR and normotensive Wistar-Kyoto (WKY) rats were chosen as controls. At the end of the follow-up, UNX-SHR had high systolic blood pressure, intense proteinuria, mesangial expansion, focal and segmental glomerular sclerosis, and tubulointerstitial lesions. In relation to WKY and SHR, UNX-SHR exhibited an increase in ET-1 gene expression in renal cortex and medulla. By in situ hybridization and immunoperoxidase staining, an overexpression of ET-1 gene and protein were seen in mesangial and glomerular epithelial cells and in some proximal tubules and vessels. Angiotensin-converting enzyme (ACE) activity was significantly increased in the renal brush border. Since in mesangial cells, angiotensin II induces ET-1 synthesis, a group of UNX-SHR received the ACE inhibitor quinapril from the time of UNX. These animals had a decrease in blood pressure, proteinuria, and serum and brush border ACE activity and in the expression and synthesis of ET-1 in all renal areas. On the whole, these data show that UNX-SHR have an upregulation of ET-1 gene and protein in several structures of the kidney compared with SHR and WKY rats. Quinapril diminished ACE activity and ET-1 expression and synthesis coincidentally with an improvement in proteinuria and morphological lesions. The beneficial effects of ACE inhibitors may be due to the diminution of both angiotensin II and ET-1 generation.
Angiotensin-Converting Enzyme Inhibitors↗
Unmet health care needs and mortality among Spanish elderly.
OBJECTIVES: This study estimates the prevalence of unmet health care needs among the elderly of Barcelona, Spain, and analyzes the association between unmet needs and mortality. METHODS: Home interviews were conducted with 1315 elderly in Barcelona. Individuals were classified as having a "health services need" if they reported being in fair, poor, or very poor health; suffering from two or more chronic conditions; or being dependent in at least one basic activity of daily living. Need was considered unmet if no visits to or from a physician in the previous 12 months were reported. Mortality was assessed from census data in August 1991. RESULTS: Between 10% and 25% of the elderly in need reported no use of health services. After a median of 60.3 months, those with unmet health care needs presented a higher risk of mortality, adjusted for several confounding factors: relative risk [RR] = 2.55 (95% confidence interval [CI] = 1.22, 5.32) for unmet activity of daily living dependency; RR = 1.80 (95% CI = 1.20, 2.70) for unmet comorbidity; and odds ratio = 1.10 (95% CI = 0.59, 2.05) for unmet poor self-rated health. CONCLUSION: Noninstitutionalized elderly individuals with unmet health care needs are at increased risk of dying.
Activities of Daily Living↗
Effects of Ajoene on lymphocyte and macrophage membrane-dependent functions.
Ajoene, (E, Z) -4, 5, 9-trithiadeca-1, 6, 11-triene 9 oxide, is a compound originally isolated from ethanolic extracts of garlic that impairs platelet aggregation by inhibiting the functional exposure of platelet integrins GPIIb/IIIa. In vitro, Ajoene is toxic for several tumoral cell lines, and exert an antiproliferative effect on T. cruzi and murine malaria parasites. Here we show that Ajoene strongly inhibited the proliferation induced in human lymphocytes by the mitogens phytohemagglutinin (PHA), phorbol myristate acetate (PMA) and anti-CD3, and the capping formation induced in B lymphocytes by anti-IgM antibodies. On macrophages, Ajoene was also found to partially inhibit the lypopolysaccharide-induced production of Tumor Necrosis Factor (TNF), and to decrease the phagocytic activity of thioglycolate-elicited mouse peritoneal macrophages for IgG-opsonized, human erythrocytes. Ajoene also partially prevented the lytic effect of human and rabbit TNF on Actinomycin D-treated WEHI 164 cells. These results strongly suggest that Ajoene is a potent modulator of membrane-dependent functions of immune cells.
Animals↗
Diagnosis of brain abscess by magnetic resonance spectroscopy. Report of two cases.
Two cases of brain abscess were diagnosed by combining magnetic resonance spectroscopy (MRS) and magnetic resonance (MR) imaging. The resonances observed in vivo were assigned by means of an in vitro MRS study of the exudates extracted during surgical aspiration of the abscesses. The technique of MRS was demonstrated to be very powerful in the differential diagnosis of brain abscesses from other brain pathologies such as neoplasms. Amino acids, probably originating from extracellular proteolysis, and other compounds, such as acetate, arising from bacterial metabolism, were visible in the MRS spectra of the abscess, whereas they are not present in spectra of neoplasms. In this sense, MRS complemented the information provided by MR imaging to achieve a correct diagnosis of brain abscesses and could be added to routine MR examinations with only a small increase in cost and time.
Adult↗
The toxic and accumulative effects of short-term exposure to cadmium in rainbow trout (Oncorhynchus mykiss).
Groups of 20 trout (Oncorynchus mykiss) were exposed for 3-w periods to different subacute oral doses of Cl2Cd (0.01, 0.025 or 0.05 microgram Cd/mL). Cadmium toxicity and accumulation were studied in kidney, liver, gills, muscle and brain weekly. Cadmium determination was carried out using atomic absorption spectrocopy (AAS) with graphite furnace. After 21 d exposure, cadmium concentrations increased significantly. In all tissues studied except muscle and brain. Cadmium storage presented the following sequence: kidney > liver > gills. At the beginning, cadmium accumulation was linearly dose dependent (r = 0.999). Then, at the highest dose (0.05 microgram Cd/mL) accumulation increased rapidly during the second week of exposure until equilibrium was reached. In contrast, liver did not accumulate cadmium selectively, suggesting that liver is able to eliminate cadmium, perhaps through metallothionein formation. Cadmium levels in gills were higher than controls (P < 0.05) and showed signs of equilibrium after the first week. According to organ weight/body weight ratios, there was similar accumulation behavior. Liver and kidney ratios increased dose dependently, but gills and brain did not have significant differences.
Absorption↗
Measurement of mechanical warpage in CR-39 lenses.
The warpage of CR-39 ophthalmic spherical lenses of a variety of powers and compressed in the radial direction is measured as a function of the applied tangential force. The lenses are cut with circular shape and then mounted on a frame specially designed to measure the tangential force by means of a calibrated coil spring. The measurements are performed with a high resolution micrometer at different points on the lens surfaces. The warpage of the two surfaces of each lens is calculated and then a quantitative value of surface power variation is given. From these data, vertex power and oblique astigmatism variation are shown. Departure of the surfaces from sphere as a function of the applied tangential force is analysed.
Eyeglasses↗
Use of the Nottingham Health Profile for measuring health status of patients in methadone maintenance treatment.
This study was conducted to assess changes in health-related quality of life over a 3-year follow-up period in a cohort of 135 opioid dependent patients using the Nottingham Health Profile (NHP) questionnaires. Data obtained at 12 months from 80 patients retained in the programme are presented. In summary, opioid addicts in a methadone maintenance programme for a 12-month period experienced an early and substantial improvement in health-related quality of life. The use of the NHP questionnaire to monitor changes in the subjective health of opioid-dependent patients over time provides new insights in the assessment of treatment effectiveness of methadone maintenance programmes.
Adult↗
Measurement of intracellular pH of maize seeds (Zea mays) during germination by 31P nuclear magnetic resonance spectroscopy.
The 31P NMR spectra of germinating maize seeds showed a single broad resonance that shifted its position as germination proceeded (studied between 0 and 10 days). The resonance was shown to originate from the phosphate groups of phytine (Mg2+, Ca2+ and K+ salt of myoinositol hexakisphosphate) in a subcellular compartment of the embryo scutellar cells. A series of calibration curves for the chemical shift dependence of the phytate resonance in the presence of Mg2+ and Ca2+ were constructed. These calibration curves allowed us to determine that an acidification of the phytate containing compartment in the seed embryo takes place, reaching a minimum at about pH 4 after three days of germination. This acidification could be important in allowing phytate solubilization for export to growing parts of the maize seedling.
Cell Compartmentation↗
Local dioptric power matrix in a progressive addition lens.
In this paper we use the formalism of the Dioptric Power Matrix to visualise and characterise the properties of a Progressive Addition Lens. For progressive addition lenses, the dioptric power matrix is point-dependent, and we have measured its elements over the lens surface by means of an automatic focimeter. We show the obtained contour plots corresponding to the matrix elements, and we compare them with the traditional sphere and cylinder graphs. Although the two representations give the same information, the advantages and disadvantages between them are analysed. The dioptric power matrix method turns out to be specially useful for the computation of prismatic effects along the lens surface.
Eyeglasses↗
[Cerebral proton spectroscopy of people infected with the human immunodeficiency virus].
BACKGROUND: This article presents a combined magnetic resonance imaging and proton spectroscopy protocol (MRI/1H-MRS) applied to study the brain of human immunodeficiency virus (HIV) infected patients. The spectroscopic results were compared with clinical and radiological parameters. PATIENTS AND METHODS: The proton spectra of 57 HIV patients and 20 control subjects were obtained from a volume of interest of 8 cm3 located in the parietooccipital region of the brain that did not include any focal lesion. The resonance areas due to N-acetyl aspartate (NAA), creatine (Cr) and choline (Cho) were obtained. The MRI exam allowed us to determine the presence of focal or diffuse lesions and the degree of atrophy. Finally, the clinical exploration included the performance of a Mini-Mental test. The NAA/Cr, NAA/Cho and Cho/Cr ratios were correlated with clinical characteristics, the result of the Mini-Mental test, the presence of lesions and the degree of atrophy. RESULTS: There were altered spectral patterns in a volume of the brain that did not contain any focal lesion. The decrease in the NAA/Cr or NAA/Cho ratios was significative when considering the presence of atrophy, the existence of signs of cognitive deficiencies or the diagnosis of AIDS-dementia complex. CONCLUSIONS: The spectral changes found in the present study suggest the existence of neuronal lesions that would be due to the HIV-infection. A combined MRI/1H-MRS study may provide a more complete information about the neurological impairment by HIV and could constitute a marker of AIDS-dementia complex.
Adult↗
Aspirin-stimulated nitric oxide production by neutrophils after acute myocardial ischemia in rabbits.
BACKGROUND: In recent studies, it has been hypothesized that the protective anti-ischemic effects of aspirin outweigh the effects of inhibition of platelet thromboxane A2 synthesis. Recently, we have found that the antiaggregating effects of aspirin significantly affect nitric oxide (NO) generation by neutrophils. METHODS AND RESULTS: The present study used circulating neutrophils from myocardial ischemic rabbits to assess the effect of aspirin on the circulating neutrophil-derived NO production and, subsequently, on the modulation of platelet activation. Neutrophils were obtained after 60 minutes of coronary artery occlusion followed by 60 minutes of reperfusion. Sham-operated animals were used as controls. The results demonstrated that aspirin stimulated the production of NO by neutrophils obtained from both sham-operated rabbits and rabbits with myocardial ischemia. However, neutrophils isolated from animals with myocardial ischemia showed an enhanced ability to generate NO in the presence of aspirin. As a functional in vitro marker, we observed that neutrophils had a NO-dependent, platelet-antiactivating effect in the presence of aspirin. In the absence of aspirin, ischemic neutrophils did not modify platelet activation, even though they produced increased amounts of NO. An inhibitory role of superoxide anion on the neutrophil-related antiplatelet effect was suggested because superoxide dismutase induced significant platelet inhibition by myocardial ischemic neutrophils in the absence of aspirin. CONCLUSIONS: Our results show that myocardial ischemia/reperfusion stimulates production of NO by circulating neutrophils, an effect that was enhanced in the presence of aspirin. These results suggest a novel interpretation of the protective effect of aspirin on myocardial ischemia damage.
Animals↗
Cellular bioenergetics after erythropoietin therapy in chronic renal failure.
After erythropoietin (rHuEPO) therapy, patients with chronic renal failure (CRF) do not improve peak O2 uptake (VO2 peak) as much as expected from the rise in hemoglobin concentration ([Hb]). In a companion study, we explain this phenomenon by the concurrent effects of fall in muscle blood flow after rHuEPO and abnormal capillary O2 conductance observed in CRF patients. The latter is likely associated with a poor muscle microcirculatory network and capillary-myofiber dissociation due to uremic myopathy. Herein, cellular bioenergetics and its relationships with muscle O2 transport, before and after rHuEPO therapy, were examined in eight CRF patients (27 +/- 7.3 [SD] yr) studied pre- and post-rHuEPO ([Hb] = 7.8 +/- 0.7 vs. 11.7 +/- 0.7 g x dl-1) during an incremental cycling exercise protocol. Eight healthy sedentary subjects (26 +/- 3.1 yr) served as controls. We hypothesize that uremic myopathy provokes a cytosolic dysfunction but mitochondrial oxidative capacity is not abnormal. 31P-nuclear magnetic resonance spectra (31P-MRS) from the vastus medialis were obtained throughout the exercise protocol consisting of periods of 2 min exercise (at 1.67 Hz) at increasing work-loads interspersed by resting periods of 2.5 min. On a different day, after an identical exercise protocol, arterial and femoral venous blood gas data were obtained together with simultaneous measurements of femoral venous blood flow (Qleg) to calculate O2 delivery (QO2leg) and O2 uptake (VO2leg). Baseline resting [phosphocreatine] to [inorganic phosphate] ratio ([PCr]/[Pi]) did not change after rHuEPO (8.9 +/- 1.2 vs. 8.8 +/- 1.2, respectively), but it was significantly lower than in controls (10.9 +/- 1.5) (P = 0.01 each). At a given submaximal or peak VO2leg, no effects of rHuEPO were seen on cellular bioenergetics ([PCr]/[Pi] ratio, %[PCr] consumption halftime of [PCr] recovery after exercise), nor in intracellular pH (pHi). The post-rHuEPO bioenergetic status and pHi, at a given VO2leg, were below those observed in the control group. However, at a given pHi, no differences in 31P-MRS data were detected between post-rHuEPO and controls. After rHuEPO, at peak VO2, Qleg fell 20% (P < 0.04), limiting the change in QO2leg to 17%, a value that did not reach statistical significance. The corresponding O2 extraction ratio decreased from 73 +/- 4% to 68 +/- 8.2% (P < 0.03). These changes indicate that maximal O2 flow from microcirculation to mitochondria did not increase despite the 50% increase in [Hb] and explain how peak VO2leg and cellular bioenergetics (31P-MRS) did not change after rHuEPO. Differences in pHi, possibly due to lactate differences, between post-rHeEPO and controls appear to be a key factor in the abnormal muscle cell bioenergetics during exercise observed in CRF patients.
Adult↗
[Osteoarticular disorders in the elderly: an approach to their population impact].
BACKGROUND: Despite the high prevalence of the osteoarticular disorders in the elderly, there are few studied about its impact on the population. The aim of the study was to estimate the prevalence and related disability associated to the osteoarthritis and rheumatic disorders in people aged 65 or more. SUBJECTS AND METHODS: The information was obtained from the Barcelona 1986 Health Interview Survey, a cross-sectional study in a representative sample of the non-institutionalized population aged 65 or more, resident in Barcelona. Information was collected about chronic conditions, perceived morbidity, perceived health status, use of health services and a specific questionnaire of functional capacity was administered. RESULTS: Fifty-one percent of the interviewed (660 of 1,287) reported having osteoarthritis or rheumatism (31.4% of the males and 63.3% of the females; p < 0.05). The proportion increased with age in males (p < 0.05) but not in females. 82% of the elderly with osteoarthritis or rheumatism reported suffering pain for this condition, being very frequent and moderate/intense in 23% of them. They also rated a worse perceived health, and reported having functional dependency and chronic limitation more frequently than elderly people without this condition. 54% of them were not taking any medical treatment and 40% of the osteoarthritics or rheumatics with very frequent and moderate/intense pain had not been visited by a physician because of their condition in the previous year. CONCLUSIONS: A high prevalence of osteoarthritis or rheumatism and an important impact on health status and health services utilization was observed in the elderly. Likewise, the results suggest that there is insufficient or inadequate coverage of health care needs for this condition.
Aged↗
Curie-temperature enhancement of ferromagnetic phases in nanoscale heterogeneous systems.
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Journal Article↗
A multicenter proton magnetic resonance spectroscopy study of neurological complications of AIDS.
Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.
Acquired Immunodeficiency Syndrome↗
Validity and reliability of the Spanish version of the Psychological General Well-Being Index.
The Psychological General Well-Being Index (PGWBI) was adapted for use in Spain. The American version was translated and back-translated independently by three bilinguals and the comprehensibility of a consensuated version was tested in a pilot study. The construct validity and internal consistency of the questionnaire were tested in 104 patients (52 high blood pressure patients attending a primary health care centre and 52 end-stage renal disease patients undergoing hemodialysis). Concurrently to the PGWBI, patients were administered the General Health Questionnaire (GHQ-12) and three psychosocial categories of the Sickness Impact Profile (SIP-PD). Patients in the dialysis group were administered the PGWBI on two occasions, two weeks apart. The PGWBI was moderately to highly correlated with the GHQ-12 (r = -0.71) and with the SIP-PD (r = -0.69). Overall internal consistency as measured by Cronbach's alpha coefficient was 0.94. By dimensions, PGWBI alpha coefficients ranged from 0.56 (Self-control) to 0.88 (Anxiety). No differences were found in mean PGWBI scores between the two groups of patients studied. Two-week test-retest intraclass correlation coefficient was 0.76. The similarity of the operating characteristics supports the contention that the Spanish and American versions of the PGWBI are conceptually equivalent. More research is needed on the reliability and responsiveness of the different dimensions of the questionnaire. Our results suggest that only global scores should be used when making individual comparisons.
Adult↗
Vitamin D insufficiency as a determinant of hip fractures.
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Aging↗