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Biomedical subjects

J D Luna

Publications and source records attributed to J D Luna.

At least 19 recordsLinked to original sources
PubMed2006

Activity of tigecycline against clinical isolates of Staphylococcus aureus and extended-spectrum beta-lactamase-producing Escherichia coli in Granada, Spain.

We evaluated the in vitro activity of tigecycline using the Etest and disk diffusion method according to Clinical and Laboratory Standards Institute guidelines against clinical isolates of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) as well as for CTX-M-9 extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and SHV ESBL-producing E. coli. All isolates were susceptible to tigecycline according to US Food and Drug Administration cut-off points. There were no differences in the activity of tigecycline between MSSA and MRSA isolates or between the presence of either type of ESBL. For each type of microorganism studied, we established the equation relating the minimum inhibitory concentration to the diameter of the zone of inhibition.

Anti-Bacterial Agents↗
PubMed2006

Levels of HSP70 in HIV(+) patients in different viroimmunological states.

The aim of the study was to establish an association between the viroimmunological status of HIV positive patients and their levels of the 70-kD heat shock protein (Hsp70). The longitudinal retrospective case study involved 61 patients at the University Hospital in Granada (Spain) from 1999 to 2002. Twenty-five patients were viroimmunologically stable, while the other 36 patients had suffered virological failure. A minimum of three blood samples were taken at intervals of at least 3 months for the patients who were stable virologically and immunologically, whereas four samples were taken for the virological failure group: two previous to the onset of virological failure, a third corresponding to the time of virological failure, and a fourth at least 3 months after remission of virological failure. Blood samples were also obtained from 20 healthy control subjects; Hsp70 levels in all were determined by enzyme immunoassay. The mean concentration of Hsp70 was 145.4 ng/ml in the HIV-infected patients as opposed to 72.1 ng/ml in the controls. While the viroimmunologically stable group showed levels similar to those of the controls (66.5 ng/ml), the mean value of Hsp70 in the virological failure group was nearly four times as high (249.1 ng/ml), yet this difference was not statistically significant. The patients treated with reverse transcriptase inhibitors were found to have significantly higher levels of Hsp70 than the other subjects. The transformed variable Hsp70/CD4(+) presents less variability than the Hsp70 value itself, giving a higher degree of statistical significance, and may be considered a useful parameter for diagnostic, prognostic, and therapeutic management of HIV positive patients.

Adult↗
PubMed2006

Plasma aminopeptidase activities in Parkinson's disease.

Parkinson's disease (PD) is an age-related neurodegenerative disease characterized by a progressive motor disorder, but frequently is accompanied by autonomic symptoms such as hypotension. Together with the decrease of dopamine, significant decreases in aminopeptidase activities have been reported in PD brains. However, up to date there are no studies about changes of aminopeptidase activities in plasma of PD patients. We studied plasma activities of alanyl-, aspartyl-(AspAP), cystinyl-(CysAP) and glutamyl-aminopeptidase (GluAP) in two groups of subjects: control (n=41) and PD (n=48). Plasma activities of AspAP, CysAP, and GluAP showed significant decreases of 24.9% (p<0.05), 39.4% (p<0.01) and 33.3% (p<0.01), respectively, in PD group. These aminopeptidases are involved in the metabolism of circulating peptides such as the ones of the renin-angiotensin system. The importance of aminopeptidases in striatal dopamine content and in neuroendocrine system in PD is discussed.

Aged↗
PubMed2004

Dentine structure and mineralization in hypocalcified amelogenesis imperfecta: a quantitative X-ray histochemical study.

OBJECTIVE: This study was undertaken in order to establish the structural and mineralization pattern of the response of dentine to alterations in enamel in hypocalcified amelogenesis imperfecta (AI). DESIGN: The images and data obtained with scanning electron microscopy and electron probe X-ray microanalysis in enamel and dentine specimens from control and affected teeth were compared in this study. PATIENTS AND METHODS: We compared 46 fragments of permanent teeth from patients with clinically diagnosed hypocalcified AI and 20 normal permanent teeth. All specimens were prepared for electron probe X-ray microanalysis. RESULTS: Dentine is characterized by thickening of the peritubular dentine and partial obliteration of the dentinal tubules that does not give rise to a compact sclerotic cast. In dentine, calcium levels were significantly higher in teeth with clinically hypocalcified AI in relation with control teeth (P < 0.001). CONCLUSIONS: Dentine is affected in hypocalcified AI increasing mineralization (narrower tubules and higher content of calcium) in response to enamel disorder.

Adolescent↗
PubMed2004

Post-transfusional hepatitis in neonates hospitalized in a Neonatal Intensive Care Unit.

OBJECTIVE: To assess the significance of increased serum transaminase levels in neonates admitted to a Neonatal Intensive Care Unit and its relationship with blood transfusion. METHODS: Follow-up prospective study of 209 patients; 177 completed follow-up, of whom 129 were transfused and 48 were not; 57 were born after full gestation and 120 were born prematurely. The activity of serum levels of ALT, AST, and GGT was measured monthly up to six months of age, and until six months after the last transfusion. At the end of follow-up, and whenever an increase in serum transaminase levels was detected, the viral agents of hepatitis A, B, C, G, TT, cytomegalovirus, Epstein-Barr, and herpes 1 and 2, and toxoplasma were studied. Viral serology was also carried out in mothers and in donors when children tested positive. RESULTS: One hundred twenty nine neonates (73%) received 461 U red blood cell transfusions (3.6 +/- 3 U/patient). ALT levels increased in 54 (30.5%) patients, of whom 46 (36%) were transfused and eight (17%) were not (p < 0.05). The independent variables were 'infection by G virus' and 'parenteral nutrition for more than 12 days'; the variable 'transfusion' was close to the limit for statistical significance. Twenty patients (11.3%) had increased serum ALT levels 2.5 times above the normal value: 18 (14%) were transfused and two (4%) were not (p = 0.106). Only the G and TT viruses were related with transfusion; patients remained asymptomatic, although most neonates were chronically infected. CONCLUSION: Follow-up showed that increased serum ALT levels are common among severely ill neonates. Blood transfusions are safe concerning most hepatotropic viruses, but transmission of viruses G and TT is possible.

Female↗
PubMed2003

Intravitreal triamcinolone acetonide injection in blind painful eyes. Intraocular steroids as a treatment for blind painful red eyes.

PURPOSE: Phthisis bulbi results from different ocular conditions. We evaluated intravitreal triamcinolone acetonide as a treatment option in blind painful eyes. METHODS: Thirty-one patients with unilateral phthisis were randomly divided into two groups. Group A received 0.3 ml (12.5 mg) triamcinolone acetonide intravitreally and Group B 0.3 ml balanced salt solution after retrobulbar anesthesia. Treatment success was assessed by subjective response to pain and clinically by biomicroscopic evaluation of conjunctival congestion. Tonometry was done before and after treatment. Follow-ups were at 24 hours, 3 weeks, 3 and 6 months, and 1 and 2 years. RESULTS: Throughout the two-year follow-up, only two patients in Group A reported pain after the procedure and were retreated, one at week 4 and the other at week 7. Conjunctival congestion was significantly lower in Group A. Two patients with hypotony before treatment had normal tension after triamcinolone. All Group B patients were reinjected with triamcinolone because pain continued after balanced salt solution injection. No severe complications were found. CONCLUSIONS: Intravitreal triamcinolone acetonide may be effective and safe for treating blind painful eyes.

Adolescent↗
PubMed2001

[Being a male or female doctor is different in medical practice].

OBJECTIVES: To identify the differences between the clinical practice (conduct) of male and female doctors and its determining factors; and to find the variability in the various conducts studied which is explained by a set of variables, gender among them. DESIGN: Cross-sectional, multi-centre descriptive study. SETTING: Andalusian health centres with populations of over 100000 inhabitants. PARTICIPANTS: Selection of 159 primary care doctors with postgraduate training by means of simple randomised sampling. 56% were men, 44% women, with power of comparisons at 68%. MEASUREMENTS AND MAIN RESULTS: Self-administered questionnaire to measure the dependent variable, overall conduct (clinical practice) and 11 dimensions of this conduct. Independent variables were: determinants of conduct identified by the theory of reasoned action (attitudes and subjective norm) and by the theory of social learning (self-efficacy and control locus), gender and other social and demographic variables and work conditions variables. Multiple linear regression models were constructed to explain each conduct analysed. Being a female doctor affects positively overall conduct and conduct in information, psycho-social guidance, prevention of obesity, active recruitment for family planning and collaboration with nurses. CONCLUSIONS: In Andalusia women general practitioners have a more marked orientation towards the psycho-social sides of care than their male colleagues. They give more information to their patients and more frequently perform preventive activities linked to their gender. They also rely on the work of their nurses more than male doctors.

Adult↗
PubMed2001

Vitreoretinal alterations following laser in situ keratomileusis: clinical and experimental studies.

BACKGROUND: The presence of vitreoretinal changes following laser in situ keratomileusis in myopia is evaluated. METHODS: Clinically, 50 patients (100 eyes) with marked anisometropic myopia, 50 low-myopic eyes (<4.00 D) and 50 high-myopic eyes (>7.00 D) were prospectively evaluated pre- and postoperatively for the presence of newly recognized entoptic phenomena (vitreous floaters, light flashes, or both), and for vitreoretinal changes using indirect depressed fundus examination, a +90 D preset lens, Goldman three-mirror contact lens, and kinetic ultrasound (KU) before and after bilateral LASIK. Patients with previous partial or total posterior vitreous cortex detachment (PVD) were excluded. Experimentally, groups of adult pigs underwent KU, retinal fluorescein angiography (FA), and electroretinography (ERG) before and after applying the microkeratome suction ring for 30 s. RESULTS: Clinically, 8% (4 eyes) had positive perception of postoperative vitreous floaters in the low myopia group, and 32% (16 eyes) in the high myopia group. Postoperative light flashes were noted only in the high myopia group, in 12% of cases. Partial or total posterior vitreous cortex detachment was detected by biomicroscopy in 2% (1 eye) of the low and in 10% (5 eyes) of the high myopia group and by KU in 4% (2 eyes) of the low and in 24% (12 eyes) of the high myopia group. Experimentally, 2 pig eyes out of 12 developed partial PVD by KU, immediately after microkeratome suction ring application. All pig eyes showed significantly diminished ERG amplitudes during and immediately after suction ring application. No FA changes or delays in retinal circulation time were noted during or immediately after removal of the suction ring. CONCLUSIONS: Vitreoretinal alterations after LASIK were demonstrated clinically mainly by KU in high myopes. Experimentally, PVD were also demonstrated. Diminished ERG recordings with normal retinal circulation following suction ring application may suggest some transient choroidal circulation abnormalities.

Adult↗
PubMed2001

Small choroidal melanoma with massive extraocular extension: invasion through posterior scleral emissary channels.

Massive orbital extension arising from a small posterior pole uveal melanoma is rare. A 75-year-old male followed for an asymptomatic choroidal nevus developed a two and a half month history of mild decrease in visual acuity. Upon clinical examination minimal enlargement of the tumor with surrounding serous retinal detachment was observed. Pre-operative magnetic resonance imaging disclosed massive extrascleral extension. Histopathology revealed that the tumor was composed of spindle B malignant melanoma cells. Multiple serial sections of the entire tumor area failed to demonstrate permeation through scleral lamellae. Instead, peripapillary perivascular short posterior ciliary vessel invasion was observed. This route of dissemination may explain the rapid growth and clinically undocumented behavior of small malignant melanomas at this location.

Aged↗
PubMed2001

Relation between vitamin D insufficiency, bone density, and bone metabolism in healthy postmenopausal women.

Although only few postmenopausal women exhibit biochemical signs of hypovitaminosis D, vitamin D insufficiency has been shown to have adverse effects on bone metabolism and could be an important risk factor for osteoporosis and fracture. We determined serum levels of 25-hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH), bone turnover markers, dietary calcium intake, and bone mineral density (BMD; measured by dual X-ray absorptiometry) in 161 consecutive ambulatory women, healthy except for osteoporosis, referred to a bone metabolic unit. The prevalence of vitamin D insufficiency [25(OH)D < or = 15 ng/ml] was 39.1%. 25(OH)D was lower in the osteoporotic subjects (15.7 +/- 5.3 ng/ml vs. 21.8 +/- 9.7 ng/ml; p < 0.001). After controlling for all other variables, lumbar spine (LS) BMD was found to be significantly associated with 25(OH)D, body mass index (BMI), and years after menopause (YSM) (R2 = 0.253; p < 0.001). For femoral neck (FN), significant independent predictors of BMD were YSM, BMI, iPTH, and 25(OH)D (R2 = 0.368; p < 0.001). The probability of meeting osteoporosis densitometric criteria was higher in the vitamin D insufficiency group (odds ratio [OR], 4.17, 1.83-9.48) after adjusting by YSM, BMI, iPTH, and dietary calcium intake. Our study shows that vitamin D insufficiency in an otherwise healthy postmenopausal population is a common risk factor for osteoporosis associated with increased bone remodeling and low bone mass.

Alkaline Phosphatase↗
PubMed2001

Differences in morphological age-related dental changes depending on postmortem interval.

Morphological methods for age estimation from teeth have been developed and applied to samples without taking the postmortem interval into consideration. We studied differences in morphological age-related changes between fresh extracted teeth and teeth from human skeletal remains in order to develop appropriate dental age estimation methods according to the time after death. Forty-three permanent teeth from dental patients were compared to 37 teeth obtained from human skeletal remains with a postmortem interval from 21 to 37 years. Morphological age-related changes were investigated by measuring variables on intact and half-sectioned teeth. A new computer assisted image analysis procedure to avoid subjectivity was developed to measure variables in sectioned specimens. Dental color, translucency length, attrition, cementum apposition, and secondary dentin showed higher values in teeth from human skeletal remains than in fresh extracted teeth. Variables obtained by morphometric analysis of computer-generated images (tooth length, tooth width, root length, and root area) showed higher values in fresh extracted teeth than in teeth from skeletal remains. The postmortem interval affects age-related morphological changes, and therefore different methods should be used for teeth of unknown postmortem interval.

Adult↗
PubMed2000

Reproducibility of patellofemoral CT scan measurements.

At least seven parameters have been described for the measurement of patellofemoral malalignment on CT scanning; three of which measure lateral patellar tilt, two lateral patellar shift and two femoral trochlear dysplasia. We studied 22 knees in 18 patients complaining of patellofemoral pain in order to investigate the reproducibility of these methods. CT scans of the patellofemoral joint were performed in each knee at 0 degrees and 20 degrees of flexion. The seven parameters were recorded from each scan by three independent observers in a blind study. The reproducibility was studied by means of the intraclass correlation coefficient (ICC). Parameters measuring lateral patellar tilt showed excellent reliability (ICC>75%). The measurements of lateral patellar shift and femoral trochlear dysplasia showed a fair or poor correlation (ICC<75%). We suggest that parameters for measuring lateral patellar tilt only should be used from CT scanning when planning treatment for patello-femoral malalignment.

Adolescent↗
PubMed2000

Factors associated with microalbuminuria in type 1 diabetes mellitus: a cross-sectional study.

In order to determine the prevalence of microalbuminuria in people with Type 1 diabetes mellitus (Type 1 DM) and identify factors associated with microalbuminuria, we studied 312 Type 1 DM patients attending in three hospitals in two Spanish regions over 6 months. Clinical characteristics, micro- and macro-vascular complications, blood pressure, 24-h urine albumin excretion, lipid profile, HbA1(c) levels, smoking habits, and family history of hypertension and diabetic nephropathy were recorded. Univariate analysis and multiple logistic regression were used to examine associations between these variables and the prevalence of microalbuminuria. We detected microalbuminuria in 29% of the patients. The prevalence of microalbuminuria was high during the second decade of diabetes and declined thereafter. Univariate analysis showed dyslipidaemia (P<0. 002), previously diagnosed hypertension (P<0.001), family history of hypertension (sibling alone P<0.006; mother alone P<0.05), family history of diabetic nephropathy (P<0.001), and laser-treated retinopathy (P<0.03) to be factors associated with the presence of microalbuminuria. Multiple logistic regression revealed an association between microalbuminuria and family history of nephropathy (OR 7.6, 3.6-16). In conclusion, in our sample the frequency of microalbuminuria seems to be related to the presence of dyslipidaemia, hypertension, and to a family history of hypertension or nephropathy.

Albuminuria↗
PubMed2000

A forced choice comfort study of olopatadine hydrochloride 0.1% versus ketotifen fumarate 0.05%.

PURPOSE: To compare the ocular comfort of two ophthalmic anti-allergic agents: olopatadine hydrochloride 0.1% and ketotifen fumarate 0.05%. SUBJECTS AND METHODS: In a double-masked, multi-centered, randomized trial, 80 subjects were asked to make a 'forced choice' based on ocular comfort between one drop of olopatadine hydrochloride 0.1% instilled in one eye and one drop of ketotifen fumarate 0.05% instilled in the contralateral eye. At one site, the incidence of adverse reactions was also reported. RESULTS: All subjects (100%) selected olopatadine as the more comfortable formulation. One site (n = 35) reported a 49% incidence of moderate burning and a 49% incidence of mild burning after ketotifen instillation. One subject (2% of population) at this site experienced no ocular discomfort with ketotifen. There were no reports of discomfort associated with olopatadine instillation. CONCLUSION: Olopatadine is a more comfortable ophthalmic preparation than ketotifen.

Choice Behavior↗
PubMed2000

Comparative effects of melatonin, L-deprenyl, Trolox and ascorbate in the suppression of hydroxyl radical formation during dopamine autoxidation in vitro.

Degeneration of nigrostriatal dopaminergic neurons is the major pathogenic substrate of Parkinson's disease (PD). Inhibitors of monoamine oxidase B (MAO-B) have been used in the treatment of PD and at least one of them, i.e., deprenyl, also displays antioxidant activity. Dopamine (DA) autoxidation produces reactive oxygen species implicated in the loss of dopaminergic neurons in the nigrostriatal pathway. In this study we compared the effects of melatonin with those of deprenyl and vitamins E and C in preventing the hydroxyl radical (8OH) generation during DA oxidation. The rate of production of 2,3-dihydroxybenzoate (2,3-DHBA) in the presence of salicylate, an *OH scavenger, was used to detect the in vitro generation of *OH during iron-catalyzed oxidation of DA. The results showed a dose-dependent effect of melatonin, deprenyl and vitamin E in counteracting DA autoxidation, whereas vitamin C had no effect. Comparative analyses between the effect of these antioxidants showed that the protective effect of melatonin against DA autoxidation was significantly higher than that of the other compounds tested. Also, when melatonin plus deprenyl were added to the incubation medium, a potentiation of the antioxidant effect was found. These findings suggest that antioxidants may be useful in brain protection against toxicity of reactive oxygen species produced during DA oxidation, and melatonin, alone or in combination with deprenyl, may be an important component of the brain's antioxidant defenses to protect it from dopaminergic neurodegeneration.

Antioxidants↗
PubMed2000

Validity of self reported utilisation of primary health care services in an urban population in Spain.

STUDY OBJECTIVE: To assess the validity and factors related with the validity of self reported numbers of visits to a primary health care centre, in comparison with the recorded number. DESIGN: Cross sectional study. SETTING: The urban area served by the Zaidín-Sur Primary Health Care Centre (Granada, Spain). PARTICIPANTS: Two population samples (236 high users and 420 normal users) who were seen at the centre from 1985 to 1991 were interviewed in 1993. MAIN RESULTS: A net tendency to overreport the actual number of visits was observed. Absolute concordance between self reported and recorded utilisation decreased as time interval lengthened, although this mainly reflected the increase in maximum variability both with time interval length and with the number of recorded visits. Corrected Spearman rho coefficients obtained between the number of self reported and recorded visits ranged from 0.602 for the two weeks before the interview to 0.678 for the year before. Regression slopes of self reported utilisation upon recorded utilisation did not change between periods. In multiple regression analyses the actual number of visits was the main factor associated with both underreporting and overreporting. Older age was also significantly associated with underreporting. Poor health status and high satisfaction with health care were significantly associated with overreporting. CONCLUSIONS: There was a substantial degree of inaccuracy in self reported utilisation, with a net tendency to overreport the number of visits. In relative terms, however, accuracy of self reports did not seem to decrease appreciably as the recall time lengthened. To compare the accuracy of different measures, it is important to take into account the maximum variability of each one. Otherwise, contradictory results may be obtained.

Adolescent↗