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Biomedical subjects

J Santos

Publications and source records attributed to J Santos.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Monitoring serum levels of gentamicin in neonates].

Newborn infants in intensive care units demonstrated a higher incidence of gestational age below 31 week. Obstetrical and neonatal diseases procedures required for the management of critically ill neonates are associated with an increased risk of infections. Gentamicin is an aminoglycoside antibiotic often used to treat gram-negative bacillary infections and suspected sepsis in neonates. The risk of toxicity or poor efficacy is further increased due to the recognised wide intra and interpatient variability of the newborn. The present work involved 49 infants of 31.3 +/- 4.1 (mean +/- SD) weeks of gestational age, weighing 1.7 +/- 0.8 kg and were treated with standard doses of gentamicin (3.8 +/- 0.9 mg/kg/day). Routine clinical care data were retrospectively collected from the medical records in the neonatal intensive-care unit at Coimbra University Hospital. Data analysis demonstrated that potentially toxic serum levels were observed in 49% of newborn infants (trough > 2 mg/L). Additionally, the obtained results also showed that 7.5% of peak concentrations were found to be higher than 10 mg/L. Potentially sub-therapeutic concentrations were observed in 15% of the patients (peak > 6 mg/L).

Critical Care↗
PubMed2003

Transcranial Doppler sonography in fulminant hepatic failure.

UNLABELLED: The clinical course of patients with fulminant hepatic failure (FHF) is often worsened by the presence of cerebral edema and endocranial hypertension. In spite of the multiple studies using Transcranial Doppler Sonography (TCDS), few have shown the cerebral blood flow (CBF) pattern among patients with encephalopathy resulting from FHF. OBJECTIVE: Our objective was to characterize the CBF pattern in these patients through the use of TCDS to provide therapeutic strategies. METHOD: The TCDS pattern was assessed in five patients diagnosed with FHF and compared with a control group who displayed critical neurologic conditions not associated with FHF. Pulsatile index, systolic, diastolic, and mean velocity of the middle cerebral artery were measured. RESULTS: The mean age of patients with FHF was 45.4 years. One hundred percent were women, with viral hepatitis as the predominant etiology. A cerebral hypoperfusion pattern was found in 80% of the FHF group and 40% of the control group. In the former group there was no evidence of hyperemia, as there was among 20% of the control group. The mean values of velocity and pulsatile index were 36.6 cm/sec and 2.4, respectively, in the FHF group and 47.8 cm/s and 1.8 in the control group (P=0.268, P=0.402). CONCLUSIONS: FHF patients show a predominance of cerebral hypoperfusion pattern with mean velocities lower than normal values and an increased pulsatile index. We recommend that clinicians take appropriate measures to improve cerebral perfusion and avoid hypoxia. Hyperventilation as a first level measure is contraindicated.

Adult↗
PubMed2003

Clinical characteristics and response to newer quinolones in Legionella pneumonia: a report of 28 cases.

Twenty-eight (11.6%) out of 241 Spanish patients enrolled in an international phase III clinical trial of mild to moderate community-acquired pneumonia (CAP) comparing gemifloxacin vs. trovafloxacin were diagnosed of Legionnaires' disease. A definite diagnosis was established by seroconversion in 13 patients of whom only 2 had a positive Legionella urinary antigen. The remaining 15 patients were possible Legionella infections based on a single elevated IgG titer (> or = 1:512). All patients had a radiologically confirmed diagnosis of pneumonia, 5 (19%) patients were older than 65, comorbidity was present in 9 (33%), and 10 (36%) had to be hospitalized. Fifteen patients were treated with oral gemifloxacin (320 mg/day) and 13 with oral trovafloxacin (200 mg/day). Overall, clinical success occurred in 25 (89.3%) patients after 7 days of treatment and only 1 patient needed a 14-day treatment. There were only one adverse event withdrawal and one clinical failure, and no patients died. In light of the favorable clinical outcome, the use of newer fluoroquinolones seems adequate for the treatment of suspected or proven Legionella pneumonia.

Community-Acquired Infections↗
PubMed2003

[Stenon's or Stensen's duct carcinoma].

Carcinomas arising from the Stensen's duct are extremely rare, and only 28 cases have been reported since 1927. Only two cases of the whole were adenoid cystic carcinoma like our case. A 83-year-old man with painless tumour of the left cheek is reported. The tumour was removed without facial nerve injury via extended parotidectomy incision and after superficial lobectomy.

Aged↗
PubMed2002

Impact of highly active antiretroviral therapy on fever of unknown origin in HIV-infected patients.

In order to assess the impact of highly active antiretroviral therapy (HAART) on the frequency and etiology of fever of unknown origin in HIV-infected patients, a retrospective study was performed on cases of fever of unknown origin observed from January 1997 to December 1999 in seven hospitals in five cities in Andalusia, Spain. During the period specified, a total of 4,858 HIV-infected patients receiving HAART and 2,787 HIV-infected individuals not receiving HAART were studied. The frequency of fever of unknown origin was 0.6% in patients receiving HAART and 3% in non-HAART patients (P=0.001). Human immunodeficiency virus infection was the only cause of fever found more frequently in the non-HAART patient group (P=0.07). The study findings suggest that the use of HAART has reduced the frequency of fever of unknown origin in HIV-infected patients, but the etiology of the condition remains mostly unchanged.

Adult↗
PubMed2002

[Local sclerosing treatment with etoxiesclerol in ORL disease: Rendu-Osler disease, granuloma, angioma...].

In a previous report, we showed the efficacy of the submucous sclerosant therapy with Etoxiesclerol (Polidocanol) in two patients with Rendu-Osler-Weber disease. We confirm, in this present study, the advantages of Etoxiesclerol in the treatment of the epistaxis in the Rendu-Osler disease, in six patients, 3 males and 3 females and likewise in two patients with non-specific granuloma of nasal septum and another patient with cavernous hemangioma of soft palate.

Adult↗
PubMed2002

[Nocardiosis in patients with HIV infection].

OBJECTIVE: To know the characteristics of nocardiosis in HIV infected patients. PATIENTS AND METHODS: Retrospective analysis of HIV infected patients with a concomitant Nocardia spp. infection in nine Andalusian hospitals. RESULTS: Eighteen cases of nocardiosis were studied. Seventeen patients were males and the mean age was 33.1 years. The risk behaviour for acquiring HIV infection was parenteral drug use in 15 patients (83.3%) and seven of them were active users when acquiring nocardiosis. The mean CD4 lymphocyte count was 66.3 106/l. The nocardiosis was manifested as disseminated disease in eight patients, only pulmonary disease in four cases, lymphocutaneous or soft-tissue nocardiosis in five, and pericarditis in the remaining patient. In the ten cases with pulmonary involvement, the chest X-ray revealed an alveolar, interstitial, and mixed pattern in five, three, and two patients, respectively. Most patients were treated with cotrimoxazole, with good clinical and microbiological responses in 88.8% of them. Some surgical procedures were required in six patients. Eight patients died, three on account of nocardiosis and five on account of other causes. There were three relapses. CONCLUSIONS: Nocardia spp. infection is rare among patients with AIDS and occurs in immunosuppressed patients and drug users. The pulmonary, cutaneous, and soft-tissue were the most commonly observed forms in our series. Despite the high frequency of disseminated infection, the response to th

Adult↗
PubMed2002

Reproducibility of TL measurements in a mixed field of thermal neutrons and photons.

The reproducibility of measurements performed with GR-100 (LiF:Mg,Ti) from the Solid Dosimetric Detector and Method Laboratory (DML) China, GR-107 (7LiF:Mg,Ti, DML), TLD-700H (7LiF:Mg.Cu,P, Harshaw) and Al2O3:Mg,Y (Hungary) in photon and mixed photon-neutron fields was investigated. Mixed-field irradiations were performed in a thermal neutron field generated at a nuclear reactor. GR-100 sensitivity decreased after mixed-field irradiations, while no significant change was found for the other materials. Using GR-100 for the dosimetry of mixed and high-intensity fields requires careful procedures.

Aluminum Oxide↗
PubMed2002

Human immunodeficiency virus infection and systemic lupus erythematosus. An unusual case and a review of the literature.

Systemic lupus erythematosus (SLE) and infection with the human immunodeficiency virus (HIV) are rarely seen in the same patient. Both diseases share clinical and serological features and the differential diagnosis is difficult, with renal manifestations being of special interest. To date, 29 cases of association between the two diseases have been reported, but the diagnosis was simultaneous in just two of these and only 18 fulfilled the ARA criteria for the diagnosis of SLE. Most patients experienced an improvement in their SLE after development of their HIV associated immunosuppression and a reactivation of lupus manifestations has also been noted after immunological recovery secondary to antiretroviral therapy. We present the case of a woman in whom HIV and SLE with renal involvement were diagnosed simultaneously.

Adult↗
PubMed2002

Unusual malignant tumours in patients with HIV infection.

The clinical charts of 2560 HIV-infected patients seen in our Unit between 01/89 and 08/01 were reviewed. All patients with a neoplasm were analysed to study the prevalence of tumours other than Kaposi's sarcoma (KS), non-Hodgkin's lymphoma (NHL) or cancer of the cervix. There were 43 unusual malignant tumours: 13 lung cancers, six leukaemias, six skin cancers, two carcinomas of the conjunctiva, two cancers of the penis, three of the anus, three of the larynx, one sarcoma of the ureter, one gastric carcinoid, one non-differentiated thyroid carcinoma, one non-differentiated prostate carcinoma, one cancer of the tongue, one cancer of the bladder, one adenocarcinoma of the rectum and one multiple IgM myeloma. Thirteen (43.3%) of the patients died, 10 (76.9%) from causes related to the tumour itself. These results suggest that HIV-infected patients have a higher prevalence of some neoplasms than the general population.

Adult↗
PubMed2002

Lupus nephritis: a retrospective review of 78 cases from a single center.

UNLABELLED: Lupus nephritis (LN) is a frequent and serious manifestation of systemic lupus erythematosus. However, the outcome has progressively improved in the last 3 decades and this was due to more efficient and early treatment of LN and comorbid situations. The aim of our study was to analyze our experience and outcome in LN, to evaluate clinicopathologic and clinicolaboratory correlations and to search for risk factors for renal and patient survival. PATIENTS AND METHODS: We conducted a retrospective study of 78 patients with biopsy-proven LN. RESULTS: Acute renal failure and subnephrotic proteinuria with microhematuria occurred each one in 39.7% of the patients, nephrotic syndrome in 16.7% and nephritic syndrome in 3.8%. The mean serum creatinine at presentation was 1.45 +/- 1.03 mg/dl and the creatinine clearance was 68.2 +/- 40.3 ml/min. Class IV LN existed in 71.8%, Class III in 20.5%, Class V in 6.4% and Class VI in 1.3%. The treatment included steroids and cytotoxic agents in 87.5% of the patients with proliferative LN. Hypertension, serum creatinine and acute renal failure at presentation, as well as significant chronicity on renal biopsy, were significantly correlated with the progression to chronic renal failure in our population. Males were more prone to develop renal flares. 3.8% of the patients died, 9% lost their renal function, 26.9% are in remission, 33.3% still have subnephrotic proteinuria and microhematuria, 7.7% have nephrotic syndrome and 19.2% have chronic renal failure. The mean global follow-up was 102 +/- 74 months and 96.2% of the patients survived. The actuarial renal survival was 96.1% in the first year; 89.9% at 5 years; and 83.7% at 10 and 20 years. CONCLUSION: We can say that hypertension, serum creatinine and acute renal failure at the onset and significant chronicity on renal biopsy, proved to be risk factors for chronic renal failure in our study population. Male gender was a risk factor for renal flares. The achieved global outcome can be considered a good result.

Acute Kidney Injury↗
PubMed2001

Evidence of a possible epigenetic inactivation mechanism operating on a region of mouse chromosome 19 in gamma-radiation-induced thymic lymphomas.

Loss of heterozygosity (LOH) analysis, performed in 68 gamma-radiation-induced primary thymic lymphomas of F1 hybrid mice, provided evidence of significant LOH on chromosome 19 in a region defined by the D19Mit106 (22 cM) and D19Mit100 (27 cM) markers (Thymic Lymphoma Suppressor Region 8, TLSR8). Cd95 and Pten, two genes mapped at this region, were inactivated in a vast majority of these tumors (85.3% for Cd95 and 61.8% for Pten). Moreover, altered expression of Cd95 and Pten occurred concomitantly in 34 of 68 (50%) thymic lymphomas suggesting a coordinated mechanism of inactivation of these genes. Surprisingly, we also found that Jak2, a proto-oncogene located between Cd95 and Pten, was simultaneously inactivated in a significant fraction of the tumors analysed (24 of 34, 70.6%). Taken together these findings and the lack of mutations in the coding sequences of the mentioned genes clearly suggest a possible regional epigenetic inactivation mechanism on mouse chromosome 19 operating during the development of these tumors.

Animals↗
PubMed2001

Role of mast cells in chronic stress induced colonic epithelial barrier dysfunction in the rat.

BACKGROUND AND AIMS: Stress may be an important factor in exacerbating inflammatory bowel disease but the underlying mechanism is unclear. Defective epithelial barrier function may allow uptake of luminal antigens that stimulate an immune/inflammatory response. Here, we examined the effect of chronic stress on colonic permeability and the participation of mast cells in this response. METHODS: Mast cell deficient Ws/Ws rats and +/+ littermate controls were submitted to water avoidance stress or sham stress (one hour/day) for five days. Colonic epithelial permeability to a model macromolecular antigen, horseradish peroxidase, was measured in Ussing chambers. Epithelial and mast cell morphology was studied by light and electron microscopy. RESULTS: Chronic stress significantly increased macromolecular flux and caused epithelial mitochondrial swelling in +/+ rats, but not in Ws/Ws rats, compared with non-stressed controls. Stress increased the number of mucosal mast cells and the proportion of cells showing signs of activation in +/+ rats. No mast cells or ultrastructural abnormalities of the epithelium were present in Ws/Ws rats. Increased permeability in +/+ rats persisted for 72 hours after stress cessation. CONCLUSIONS: Chronic stress causes an epithelial barrier defect and epithelial mitochondrial damage, in parallel with mucosal mast cell hyperplasia and activation. The study provides further support for an important role for mast cells in stress induced colonic mucosal pathophysiology.

Analysis of Variance↗
PubMed2001

Adaptation of stress-induced mucosal pathophysiology in rat colon involves opioid pathways.

Acute stress increases ion secretion and permeability of rat colonic epithelium. However, it is not known if stress-induced mucosal changes are subject to adaptation. Wistar-Kyoto rats were exposed to either continuous water-avoidance stress (CS) for 60 min or intermittent stress (IS) for three 20-min periods. Distal colonic segments were mounted in Ussing Chambers, and ion-transport [short-circuit current (I(sc))] and permeability [conductance and flux of horseradish peroxidase (HRP)] parameters were measured. CS significantly increased I(sc), conductance, and HRP flux compared with control values. In contrast, in IS rats these variables were similar to those in nonstressed controls. To study the pathways involved in IS-induced adaptation, rats were pretreated intraperitoneally with the opioid antagonists naloxone or methylnaloxone. Opioid antagonists had no effect on values in control or CS rats. However, in the IS group, naloxone and methylnaloxone reversed the adaptive responses, and all variables increased to CS values. We conclude that stress-induced colonic mucosal pathophysiology is subject to rapid adaptation, which involves opioid pathways.

Adaptation, Physiological↗
PubMed2001

Disease knowledge and attitudes toward predictive testing and prenatal diagnosis in families with Machado-Joseph disease from the Azores Islands (Portugal).

OBJECTIVE: Machado-Joseph disease (MJD) reaches its highest prevalence world-wide in the Azores, thus constituting a public health problem in these islands. The aim of the study was thus to (1) determine the level of knowledge about the disease; (2) estimate the expected level of request for predictive testing, and (3) analyse the intentions of at-risk individuals concerning their reproductive decisions. METHODS: A questionnaire on these points was distributed to 42 affected and 36 at-risk individuals. RESULTS: As expected, the educational level of the respondents was significantly associated with the level of knowledge about the disease. The survey indicated that 83.3% of the at-risk individuals would make use of predictive test and that 77.8% would make use of prenatal diagnosis. Of the latter, 36.1% would terminate pregnancy if confronted with a positive result for the fetus. CONCLUSIONS: The level of knowledge about MJD in the Azorean families is considered to be fair. Although the actual behavior can prove to be different from the intentions put forward by at-risk individuals based solely on the results of this study we can estimate that the request for a predictive test would be quite high. The intentions expressed by at-risk individuals seem to indicate that the prenatal diagnosis will have an effect on their reproductive decisions. Results obtained certify the importance of implementing genetic testing for MJD in the Azores.

Attitude to Health↗
PubMed2001

Incidence rate and spatio-temporal clustering of type 1 diabetes in Santiago, Chile, from 1997 to 1998.

OBJECTIVE: To estimate the incidence rate of type 1 diabetes in the urban area of Santiago, Chile, from March 21, 1997 to March 20, 1998, and to assess the spatio-temporal clustering of cases during that period. METHODS: All sixty-one incident cases were located temporally (day of diagnosis) and spatially (place of residence) in the area of study. Knox's method was used to assess spatio-temporal clustering of incident cases. RESULTS: The overall incidence rate of type 1 diabetes was 4.11 cases per 100,000 children aged less than 15 years per year (95% confidence interval: 3.06 - 5.14). The incidence rate seems to have increased since the last estimate of the incidence calculated for the years 1986 - 1992 in the metropolitan region of Santiago. Different combinations of space-time intervals have been evaluated to assess spatio-temporal clustering. The smallest p-value was found for the combination of critical distances of 750 meters and 60 days (uncorrected p-value = 0.048). CONCLUSIONS: Although these are preliminary results regarding space-time clustering in Santiago, exploratory analysis of the data method would suggest a possible aggregation of incident cases in space-time coordinates.

Adolescent↗