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Biomedical subjects

J Ruiz

Publications and source records attributed to J Ruiz.

At least 19 recordsLinked to original sources
PubMed1992

Hepatitis B and C viral infections in patients with hepatocellular carcinoma.

The prevalence of hepatitis B and C virus infections was studied in 70 patients diagnosed as having hepatocellular carcinoma. In addition to viral serological markers, serum hepatitis B virus DNA and hepatitis C virus RNA were determined with a nested polymerase chain reaction assay. Twelve patients (17%) were HBsAg positive, 26 (37%) had antibodies to HBs, HBc or both and 32 (46%) were negative for all hepatitis B virus serological markers. Prevalence of the antibody to hepatitis C virus was 63% (44 patients). Hepatitis B virus DNA was detected in 24 of the 66 tested patients (36%). Twelve of these hepatitis B virus DNA-positive patients were HBsAg negative (seven were positive for antibody to HBs, antibody to HBc or both and five were negative for all hepatitis B virus serological markers). Hepatitis C virus RNA was found in 42 of 68 patients (62%). A high correlation (95%) existed between hepatitis C virus RNA and hepatitis C virus antibodies. Nevertheless, two patients without antibody to hepatitis C virus had serum hepatitis C virus RNA sequences. Coinfection by the two viruses was detected in nine subjects (14%), but no clinical differences were found between these and the rest of the patients. We conclude that nearly 90% (62 of the 70 patients studied) of cases of hepatocellular carcinoma in our geographical area are related to hepatitis virus infections (detected by serological or molecular studies). Hepatitis C is more prevalent than hepatitis B virus in patients with hepatocellular carcinoma, and the infection is still active when the tumor is diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Role of selective digestive decontamination (SDD) in the prevention of nosocomial pneumonia (NP): is gastric decontamination necessary?

In the course of a prospective selective digestive decontamination (SDD) trial to prevent nosocomial pneumonia (NP) during mechanical ventilation (MV), we carried out serial cultures of gastric aspirate to assess the importance of gastric colonization for potential respiratory pathogens and its relationship to the simultaneous gastric pH, to whether the patients were receiving Sucralfate or Ranitidine and to the nutritional biochemical parameters. If NP developed, a bronchial sample was taken by fibreoptic bronchoscopy to determine the causal organisms and its relationship to the previous gastric isolated. Results show: 1) Increase in aerobic Gram negative bacilli colonization during hospitalization. 2) Direct relationship between colonization level and gastric pH. 3) Greater pH in ranitidine vs sucralfate group. 4) Low incidence of NP (11%), the majority of these (66%) being early. 5) No bacteriological correlation between gastric colonization and aetiological agents of NP. 6) Close relationship between pharyngeal colonization and causative germs of pulmonary infection (40%).

Adolescent↗
PubMed1992

Increased [3H] raclopride binding sites in postmortem brains from schizophrenic violent suicide victims.

The specific binding of the D2-dopamine receptor antagonist radioligand [3H] raclopride was quantitated in the postmortem caudate and frontal cortex from schizophrenic suicide victims and control subjects. In schizophrenic suicides the density of binding sites (Bmax) was higher (40%, P < 0.05) in the caudate, whereas it did not change in the cortex as compared to those in controls. The apparent dissociation constants (KD) were also found increased both in caudate (24%) and cortex (75%) from schizophrenics, but these apparent decreases in receptor affinity did not reach statistical significance. The mean Bmax value in drug-free schizophrenic suicides (n = 3) did not differ from the Bmax value in neuroleptic drug-treated schizophrenics (n = 7) but it was found increased in respect to control subjects (n = 9). No differences in [3H] raclopride binding were observed between non-schizophrenic suicide victims (n = 4) and matched controls (n = 4), suggesting that the modifications of D2-dopamine receptors in schizophrenia are not related to suicide.

Adult↗
PubMed1992

Modification of the methodology of stool culture for Salmonella detection.

A total of 4,284 H2S-positive colonies isolated on salmonella-shigella agar and 4,350 isolated on Hektoen agar were flooded with 5 microliters of a reagent (MUCAP test; Biolife Italiana S.r.l., Milan, Italy) and observed after 3 to 5 min for the development of fluorescence produced in the presence of the C8 esterase enzyme. All of the 794 colonies isolated on salmonella-shigella agar and the 752 isolated on Hektoen agar and identified as positive for Salmonella spp. with conventional biochemical tests were found positive with the MUCAP test (the sensitivity was 100% and the negative predictive value was 100% for both media). Moreover, only six isolates identified by conventional biochemical tests as Proteus vulgaris were MUCAP test positive (the specificity was 99.8% and the positive predictive value was 99.2% for both media). On the basis of these results, we propose the use of the MUCAP test as a method for the screening of H2S-positive colonies and only subculturing on Kliger agar of those colonies which are MUCAP test positive. The MUCAP test is a rapid method for the presumptive detection of Salmonella spp. and reduces the work and material involved in testing.

Bacteriological Techniques↗
PubMed1992

Measurement of maximal expiratory pressure: effect of holding the lips.

BACKGROUND: Minor differences in technique may account for the wide range of published normal values of maximum expiratory and inspiratory pressures. The effects of holding the lips while the subject performed a maximal expiratory pressure manoeuvre were investigated in this study. METHODS: Maximum static expiratory pressures (PEmax) obtained with a cylindrical tube by means of lip compression by the subject and technician aided compression were compared in 20 men (mean age 27 years) and 20 women (mean age 28 years). RESULTS: Technician aided lip compression was associated with higher maximum expiratory pressure than compression by the subject in both men (195 v 110 cm H2O) and women (134 v 80 cm H2O). CONCLUSION: Compression of the lips and corners of the mouth should be performed by a trained technician for maximum expiratory pressure measurements when a cylindrical mouthpiece is used.

Adult↗
PubMed1992

Effects of inhaled platelet activating factor on bronchial responsiveness in patients with symptomatic and asymptomatic pulmonary embolism.

To determine the possible role of platelet-activating factor (PAF) in pulmonary embolism (PE), the reactivity of the airways to inhaled PAF, using doses ranging from 6.25 to 400 micrograms, was examined in 24 patients with a past episode of PE. Twelve of these patients had experienced acute respiratory insufficiency during the episode (with or without additional symptoms). None of the remaining 12 patients had experienced any respiratory symptoms during the PE episode. Diagnosis was established by means of a ventilation-perfusion lung scan performed when admitted to the hospital because of deep venous thrombosis (DVT) in the lower limbs. Nonspecific bronchial reactivity as measured by the response to bronchoprovocation testing with methacholine showed no significant differences between both groups. PAF caused a dose-dependent bronchoconstriction defined by at least a 35 percent decrease in specific airway conductance (SGaw) in all patients. The average dose of PAF needed to decrease SGaw 35 percent was significantly lower in patients who had had a symptomatic PE than in those with asymptomatic PE (p = 0.011). This finding suggests that patients who suffered from symptomatic PE may present a greater airway reactivity to inhaled PAF. This different behavior might explain the existence of some of the respiratory symptoms of PE, which could be attributed to PAF-related effects. However, additional studies are needed to evaluate the role of PAF in PE.

Administration, Inhalation↗
PubMed1992

[Acute renal insufficiency secondary to the use of angiotensin converting enzyme inhibitors in 2 patients without renal artery stenosis].

Two female patients who developed acute renal failure secondary to the use of angiotensin converting enzyme (ACE) inhibitors for hypertension are presented. None had renal artery stenosis on angiography or duplex doppler ultrasound examination. A 66 year old patient with a single functioning kidney recovered basal renal function; the other patient, aged 77 years, remained with a permanent severe renal damage. Risk factors were advanced age, mild chronic renal failure due to nephrosclerosis and diuretic use. We conclude that acute renal failure related to ACE inhibitors may be severe and can occur even in patients without renal artery stenosis. Diuretics, associated to ACE inhibitors, should be prescribed with caution, specially in older hypertensive patients with pre-existing chronic renal failure. Diabetic patients are at special risk due to the high incidence of small vessel disease in them.

Acute Kidney Injury↗
PubMed1991

[Enterococcus faecalis bacteremia].

BACKGROUND: This study was prompted by the increasing role of E. faecalis in hospital acquired infections, their morbidity and mortality and the development of resistances. The aim of the study was to define the epidemiological features, the predictive factors of bacteremia and the mortality prognosis in a group of patients with E. faecalis bacteremia. METHODS: The clinical and epidemiological features on admission, after 3 days and one week of therapy and one month after therapy were evaluated in 57 cases of true E. faecalis bacteremia. The effectiveness of therapy was assessed by the rate of clinical and microbiological cures, deaths and survivals. RESULTS: The incidence of E. faecalis bacteremia was 5.9%. 78% of them were hospital acquired, with unknown source in 31%. Generally, they developed in surgical services and usually the patients had received antibiotic treatment or instrumentation. 63% of bacteremias were monomicrobial. Male sex, hospitalization (particularly in surgical or intensive care services), underlying disease of rapidly fatal prognosis, the previous use of third generation cephalosporins and/or ciprofloxacin, and previous instrumentation or surgery were found to be predictive factors of bacteremia. On the other hand, underlying disease with rapidly fatal prognosis, with initial poor or critical clinical condition, the previous use of wide spectrum antibiotics, polymicrobial bacteremia, and the presence of leukocytosis or complications were significantly associated with a higher mortality. The resistance rates ranged between 42% to kanamycin and 1% to amikacin. CONCLUSIONS: In view of the results, a better knowledge of the predictive and prognostic factors of E. faecalis bacteremia is required for prevention and treatment.

Enterococcus faecalis↗
PubMed1991

Association of Escherichia coli HEp-2 adherence patterns with type and duration of diarrhoea.

373 (59%) out of 636 faecal specimens obtained during the first 2 years of life of 72 Mexican children yielded adherent Escherichia coli (HEp-2 cells). Strains with localised adherence were significantly associated with acute non-bloody diarrhoea, whereas strains with aggregative adherence were significantly associated with persistent diarrhoea. Half the strains with localised adherence were not enteropathogenic E coli serotypes nor did they hybridise with an enteropathogenic E coli adherence factor DNA probe. All strains with localised adherence gave a positive fluorescent actin staining (FAS) assay, irrespective of serotype. One-third of children colonised by aggregative strains had bloody diarrhoea. Isolation of strains with diffuse adherence was not related to type or duration of diarrhoea but was generally associated with isolation of another pathogenic organism.

Acute Disease↗
PubMed1991

Presumptive identification of Salmonella enterica using two rapid tests.

Two rapid test for early detection of Salmonella enterica, the cytochrome oxidase test and a fluorescence test, were evaluated in 1,200 colonies which had been isolated from human feces and cultured on MacConkey and Salmonella-Shigella media. Using the fluorescence test there were no false negative results (sensitivity 100%) and of 205 positive cases 62 did not correspond biochemically to salmonella (specificity 94.1%); 44 of these 62 were positive in the cytochrome oxidase test, raising the specificity to 98.2%. In conclusion, the combination of the two tests could be very useful due to the ease of performance, low cost and excellent results obtained.

Culture Media↗
PubMed1991

Comparison of the efficacy of three different treatments with imipenem versus the classical clindamycin plus tobramycin in experimental peritonitis.

This study compares the efficacy of three different treatment modalities of imipenem/cilastatin and the conventional clindamycin plus tobramycin in an experimental model of intra-abdominal sepsis. 145 Wistar rats were used. 40 served as control and 105 as study groups. A capsule with 0.5 ml of inoculum was surgically implanted in the peritoneal cavity. The inoculum was prepared from human feces of healthy volunteers, with a composition of E. coli 10(6), E. faecalis 10(6), B. fragilis, Clostridium sp 10(5) to 10(6) and anaerobic streptococci 10(5) to 10(6). Eighty animals were treated with imipenem/cilastatin and divided in 3 subgroups: "short pretreatment"--29 animals treated 1 hour prior to surgery and 3 days after; "short"--26 animals starting treatment 2 hours post-surgery and continuing it for 3 days; and "long"--25 animals treated for 10 days, starting 2 hours post-surgery. 25 animals received clindamycin plus tobramycin for 10 days. Mortality and the presence of visceral and peritoneal abscesses were the endpoints of the study. The control group had 100% mortality. There were no statistically significant differences among the treated groups although lower mortality was obtained with "short pretreatment" and "long" treatment with imipenem. The presence of abscesses were statistically significant between the imipenem and the combination group. In the imipenem groups, the "short pretreatment" and the long treatment had fewer abscesses than the short one. We conclude that imipenem may be a good alternative monotherapy to conventional therapy with clindamycin plus tobramycin. The "short pretreatment" seemed as good as the long one and better than the short treatment.

Abscess↗
PubMed1991

Inhibition of localized adhesion of enteropathogenic Escherichia coli to HEp-2 cells by immunoglobulin and oligosaccharide fractions of human colostrum and breast milk.

Secretory IgA (sIgA) purified from colostrum and breast milk obtained from 14 women inhibited the localized adherence of an enteropathogenic Escherichia coli (EPEC) to HEp-2 cells. Inhibition decreased as lactation continued even when the concentration of sIgA was maintained constant at 1 mg/ml. sIgA responded to a 94-kDa plasmid-encoded outer membrane protein implicated as the EPEC adherence factor. An oligosaccharide-enriched fraction (OEF) from these samples also inhibited the attachment of this EPEC. Inhibition by OEFs decreased as lactation continued because of a general reduction in oligosaccharide content. Localized adherence of six other EPEC was also inhibited by sIgA and OEF, whereas attachment of isolates with diffuse or aggregative adherence was not inhibited by these fractions. Experiments with purified oligosaccharide fractions revealed that EPEC attach to HEp-2 cells through a carbohydrate-mediated mechanism based on the preferential recognition of fucosylated residues in human milk.

Bacterial Adhesion↗
PubMed1991

Lung dust content in idiopathic pulmonary fibrosis: a study with scanning electron microscopy and energy dispersive x ray analysis.

Examination with an optical microscope and polarised light is not sensitive enough to detect low diameter asbestos fibres. This limitation implies that some cases of asbestosis can be erroneously diagnosed as idiopathic pulmonary fibrosis (IPF) if asbestos bodies are not found in the standard examination of abnormal tissue. To determine whether IPF is over-diagnosed, a study was carried out with scanning electron microscopy (SEM) and energy dispersive x ray analysis (EDXA) on 25 samples previously diagnosed as IPF at the standard examination. Scanning electron microscopy will show the presence of low diameter fibres in the lung without tissue destruction, and these fibres can be identified using EDXA. The quantitative and qualitative results for lung tissue from patients diagnosed as having IPF were compared with the results of the examination of 25 samples of normal lung. Most of the samples from patients diagnosed as having IPF showed only occasional inorganic particles (less than 10 particles/SEM field at 160 x), results equivalent to the results obtained in normal lung. Two cases of IPF, however, showed innumerable asbestos fibres (greater than 100 fibres/SEM field). One of these two patients had an antecedent of brief exposure to asbestos. No environmental antecedent was found in the second patient. Asbestosis was the final diagnosis for these two patients. The examination of inorganic particles in normal lungs showed mainly non-fibrous silicates (61.4%) and particles of heavy elements (34.9%). Only one asbestos fibre was found (0.9%). It is concluded that standard pathological techniques overdiagnose IPF in a few cases in which asbestos bodies are not found with the optical microscope.

Adult↗
PubMed1991

Upper-extremity deep venous thrombosis and pulmonary embolism. A prospective study.

We prospectively evaluated the prevalence of pulmonary embolism (PE) in 30 consecutive patients with proved deep venous thrombosis (DVT) of the upper extremity. Ten patients (seven male and three female; mean age, 43 years) had primary DVT, and 20 patients (14 male and six female; mean age, 52 years) had catheter-related DVT. Ventilation-perfusion lung scans were routinely performed at the time of hospital admission to all but one patient (one patient was critically ill, and he died four days after DVT diagnosis because of massive PE). Lung scan findings were normal in nine of ten patients with primary DVT, and they were indetermine in the remaining patient. By contrast, perfusion defects were considered highly suggestive of PE in four patients with catheter-related DVT; two patients had indeterminate lung scans, and 13 patients had normal scans. We conclude that PE is not a rare complication in upper extremity DVT, and that patients with catheter-related DVT seem to be at a higher risk.

Adult↗