Detection of the saa gene in verotoxin-producing Escherichia coli from ruminants

A total of 163 verotoxin-producing Escherichia coli (VTEC) strains isolated from diarrheic and healthy cattle, sheep, and goats were analyzed for the presence of the saa gene by polymerase chain reaction. Seventeen (45.9%) and 5 (29.4%) of the VTEC isolated from healthy cattle and diarrheic calves, respectively, had the saa gene. None of the saa-positive strains carried the eae gene, but 20 of the 22 saa positive were ehxA positive. In contrast with cattle VTEC, none of the VTEC isolated from small ruminants were saa positive. These results show that the saa gene is commonly associated with bovine eae-negative VTEC strains but not with ovine or caprine VTEC strains.

Multiple environmental signals determine the transcriptional activation of the mycoparasitism related gene prb1 in Trichoderma atroviride

Trichoderma atroviride parasitizes a large variety of phytopathogenic fungi. This characteristic has allowed its use as a biological control agent. The production of hydrolytic enzymes appears to be a key element in the parasitic process. Among the enzymes released by Trichoderma, the proteinase Prb1 plays a major role. We show here that the corresponding gene ( prb1) is subject to nitrogen catabolite repression. Accordingly, induction of prb1 transcription by Rhizoctonia solani cell walls and by osmotic stress requires release from a repressed condition, which is determined by nitrogen availability. Furthermore, the transcription pattern of the prb1 gene was not affected when an inhibitor of p38-Hog1, a regulator of the response to osmotic shock, was used. In contrast, a MEK1/2 (MAPK/ERK) inhibitor blocked prb1 transcription in response to nitrogen limitation, indicating that the pathway employed in the nitrogen response involves proteins similar to p42-p44. Fusion of the prb1 promoter to the gfp reporter gene allowed the detection of a novel regulatory element, providing an initial insight into the nature of the sites that control prb1 expression.

Antiphospholipid antibodies: a risk factor for occlusive retinal vascular disorders. Comparison with ocular inflammatory diseases

OBJECTIVE

To evaluate the prevalence of antiphospholipid antibodies (aPL) together with immunological characteristics of patients with occlusive retinal vascular disorders (ORVD) with and without risk factors (systemic arterial hypertension, diabetes mellitus, hyperlipidemia, and embolizing cardiac disease) for retinal occlusions compared to patients with ocular inflammatory diseases (OID) and healthy controls.

METHODS

Sixty-eight patients with ORVD, 45 patients with OID, and 49 healthy persons were prospectively studied. Serologic studies included determination of anticardiolipin antibodies, lupus anticoagulant, antinuclear antibodies (ANA), levels of complement 4 and 3, total hemolytic complement (CH100), and circulating immune complexes (CIC).

RESULTS

Elevated levels of aPL were detected in 16 (24%) patients with ORVD compared to 4 (9%) patients with OID (OR 3.15, p < 0.05) and 4 (8%) controls (OR 3.46, p < 0.05). No significant differences were seen in the prevalence of aPL comparing risk factor-positive patients with ORVD (8 of 33, 24%) to risk factor-free patients with ORVD (8 of 35, 23%). A higher frequency of positive ANA, elevated IgA, and increased CIC were detected in aPL positive patients with ORVD compared to patients with OID.

CONCLUSION

Detection of aPL in patients with ORVD may help determine which patients are eligible for prophylactic treatment. An immunologic profile characterized by high prevalence of ANA, CIC, and elevated IgA distinguishes ORVD patients with aPL from inflammatory ophthalmologic disorders.

[Gemcitabine in the treatment of 4 patients with cholangiocarcinoma]

Cholangiocarcinoma is a biliary tree cancer of unknown etiology, whose symptoms are unspecific and is usually detected in advanced stages. Surgery continues to be the only curative therapy. Median survival in patients with inoperable tumors ranges between 5 and 8 months. There are few studies on the effects of chemotherapy, with a very small response. We report four patients with advanced cholangiocarcinoma, treated with gemcitabine 1000 mg/m2, weekly for 3 weeks every 28 days. There was a stabilization of tumor size and symptoms were alleviated. Toxicity was low and there was a probable prolongation of survival.

Quality assurance of point-of-care testing in the Costa del Sol Healthcare Area (Marbella, Spain)

Traditionally, point-of-care testing (POCT) has been used throughout the healthcare system without the involvement of the central laboratory. After an exhaustive study of the situation of these laboratories in the Costa del Sol Healthcare Area, we designed a quality control program for the POCT. This program targeted the tests done at the points of care throughout the hospital and the Primary Healthcare Area (PHA), using the Joint Commission on Accreditation of Healthcare Organisations (JCAHO) standards for waived testing. We developed two programs: hospital-based tests and ambulatory POCT for outpatients in PHA. The hospital-based POCT apparatus was used for gases, glucose, qualitative urinalysis, Helicobacter pylori detection in gastrointestinal biopsies and coagulation tests. Ambulatory POCT was used to detect glucose, qualitative urinalysis and pregnancy tests. The personnel responsible are nursing staff with no continuing training program. There was no explicit quality control program and most of the results were used as screening except for glucose in the neonatal department. Criteria for selection of kits and devices were basically based on ergonomic and economic evaluation. Therefore, we performed an evaluation of precision and accuracy of two glucose meter devices. We implemented the internal and external quality programs (IQC and EQC) for glucose testing. We elaborated a guide of standard proceedings for quantitative and qualitative POCT and created an annual course for nursing staff. The annual evaluation of the indicators showed 96% for degree of compliance with IQC; 54% of nursing staff participated in the training program; 98% of the glucometers were operating; and 88% agreement between central laboratory and POCT. As there is no previous experience in our healthcare system, this represents a promising new area of working with nurses, who show great interest in participating in these new programs.

[Efficacy of gemcitabine in the gallbladder cancer. Initial experience in 4 cases]

Surgery continues to be the only curative therapy for gallbladder cancer, but useful in very few patients. Mean survival of patients with gallbladder cancer, that are out of the reach of surgery, is 3 months. The few clinical trials of chemotherapy for this disease, report very low success rates. We report four patients with advanced gallbladder cancer, treated with gemcitabine in an intravenous dose of 1000 mg/m2, given in 30 min, once a week during three consecutive weeks, every 28 days. There was a partial response that lasted 40.3 23.2 weeks with a mean survival of 59.75 17 weeks. One patient survives without evidences of disease after 17 months of the diagnosis of an advanced cancer. In all patients, symptoms were alleviated, functional status and quality of life improved. Toxicity was mild and did not require reduction in doses or delay in therapy. Therefore, this medication deserves further investigation for the treatment of gallbladder cancer.

A prospective search for ocular lesions in hospitalized patients with significant bacteremia

The purpose of this study was to determine the prevalence, risk factors, and prognostic value of ocular lesions in unselected patients with bacteremia. A total of 202 bacteremic patients, 101 nonbacteremic septic patients, and 90 nonseptic control patients were compared in a prospective, controlled, observational study. Ocular lesions related to bacteremia were found in 12% of the bacteremic group, 5% of the septic group, and 2% of the control group. Ocular lesions were significantly more frequent in the bacteremic patients than in the control patients (P=.007). The severity of the clinical condition and the presence of fungemia predict independently a higher risk of ocular lesions. Mortality rates among bacteremic patients with and without ocular lesions were, respectively, 32% and 8% (P<.01; OR, 3.99). The asymptomatic nature of most ocular lesions in patients with bloodstream infections and the impossibility of amelioration in most cases lead us to recommend ophthalmologic examination for bacteremic patients only when prognostic information is needed.

Antiphospholipid antibodies and retinal thrombosis in patients without risk factors: a prospective case-control study

PURPOSE

To determine the prevalence of antiphospholipid antibodies and other immunologic abnormalities in patients with occlusive retinal vascular events, exempt from conventional risk factors of retinal thrombosis.

METHODS

Forty patients with retinal vascular occlusion (26 with retinal vein occlusions, eight with arterial occlusions, two with combined venous and arterial occlusions, and four with venous occlusions plus vasculitis), free of main accepted risk factors for retinal thrombosis, were prospectively screened for antiphospholipid antibodies (anticardiolipin-antibodies and lupus anticoagulant) and other immunologic abnormalities. Fourteen patients were younger than 50 years. Prevalence and mean values of antiphospholipid antibodies (aPL) were compared with those in a homogeneous control group of 40 patients.

RESULTS

The prevalence of antiphospholipid antibodies in the study group was 22.5% (nine of 40). Comparison with control group prevalence (5% [two of 40]) showed a statistically significant difference (P = .04). Six patients in the study group disclosed positivity for IgG-anticardiolipin antibodies, one patient for IgM anticardiolipin antibodies, and two patients for both isotypes IgG and IgM anticardiolipin antibodies. The antibody assay for lupus anticoagulant was negative for all patients. Three patients were diagnosed as having primary antiphospholipid antibody syndrome and are undergoing systemic anticoagulant therapy. Relevant immunologic abnormalities were also found (27.5% with antinuclear antibodies, 35% with elevation of circulating immune complexes, 35% with complement deficiency, 30% with positive rheumatoid factor, and 17.5% with positive C-reactive protein). Thirteen patients (32.5%) had more than four parameters altered. No significant association was found between prevalence or mean values of anticardiolipin antibody and patients younger than 50 years.

CONCLUSIONS

The high prevalence of anticardiolipin antibodies in patients with vaso-occlusive retinopathy exempt from conventional risk factors, and the relevant diagnostic and therapeutic implications, lead us to recommend a systematic search for specific antiphospholipid antibodies in such patients.

Immunotherapy with a mass unit Parietaria judaica extract: a tolerance study with evidence of immunological changes to the major allergen Par j 1

Specific immunotherapy with Parietaria judaica pollen extract has been proven to be effective in the treatment of patients with respiratory allergy induced by this pollen. Nevertheless, there is some controversy about its tolerability. We conducted an open uncontrolled study to evaluate the tolerability of an aluminium adsorbed P. judaica pollen extract whose major allergen (Par j 1) content was known. Changes in immunological parameters to a complete P. judaica extract and to a purified Par j 1 preparation were monitored. Twenty-one patients (12 women, 9 men; mean age 30.2 years) suffering from rhinoconjunctivitis and/or asthma due to Parietaria pollen were enrolled. The maximum dose was established at 10 BU/ml (0.6 microgram Par j 1). Skin and conjunctival reactivity as well as serum levels of specific IgE, IgG, IgG1 and IgG4 were evaluated before therapy (T0), when 1 BU was given (T1), 2 weeks after the maintenance dose was reached (T2) and after the pollen season (T3). Four-hundred and fifteen doses were administered during immunotherapy. Only one systemic reaction (0.24% of doses) and two local reactions were registered. Reactions occurred during the administration of the highest concentrated vial. Before immunotherapy, purified Par j 1 accounted for 94.2% of the cutaneous response elicited by the complete extract. A statistically significant decrease in cutaneous response was detected after 8 weeks of treatment. There were no significant changes in conjunctival reactivity throughout the study. Specific IgG, IgG1 and IgG4 showed a pronounced and significant increase during the study, while specific IgE levels initially decreased and increased after the pollen season. The kinetics of specific antibodies to P. judaica complete extract and purified Par j 1 showed a parallel trend. The present study demonstrates that immunotherapy with P. judaica extract is well tolerated in patients suffering from rhinoconjunctivitis and/or asthma due to Parietaria pollen. This therapy induces specific changes in the immunological response to P. judaica and to purified Par j 1. These changes can be detected at very early stages of therapy.

[Preliminary results of horizontal gastroplasty with Roux in Y anastomosis in patients with severe and morbid obesity]

BACKGROUND

Morbidly obese subjects have a high incidence of complications. The poor results of dietary treatments, has prompted the search of new therapies for obesity and among these, surgical procedures.

AIM

To report the long term results of horizontal gastroplasty with Roux en Y anastomosis in morbidly obese subjects.

PATIENTS AND METHODS

Fifty patients with an initial body mass index of 41.3 +/- 6 kg/m2 have been subjected to a horizontal gastroplasty with Roux en Y anastomosis. During the study period, surgical techniques were modified, reducing the gastric pouch size, adding a truncal vagotomy, cholecystectomy, and increasing the length of the Roux en Y loop from 70 to 100 cm. Twenty five patients have been followed for two years.

RESULTS

There was no operative mortality and one patient had an anastomotic leak that required 35 days of hospitalization. During follow up, in one patient, the stapled suture line loosened. After two years of follow up, weight decreased from 112 +/- 19 to 77.2 +/- 14 kg.

CONCLUSIONS

Horizontal gastroplasty with Roux en Y anastomosis achieved an adequate weight loss with a low rate of complications in this group of morbidly obese subjects.

Role of the Trichoderma harzianum endochitinase gene, ech42, in mycoparasitism

The role of the Trichoderma harzianum endochitinase (Ech42) in mycoparasitism was studied by genetically manipulating the gene that encodes Ech42, ech42. We constructed several transgenic T. harzianum strains carrying multiple copies of ech42 and the corresponding gene disruptants. The level of extracellular endochitinase activity when T. harzianum was grown under inducing conditions increased up to 42-fold in multicopy strains as compared with the wild type, whereas gene disruptants exhibited practically no activity. The densities of chitin labeling of Rhizoctonia solani cell walls, after interactions with gene disruptants were not statistically significantly different than the density of chitin labeling after interactions with the wild type. Finally, no major differences in the efficacies of the strains generated as biocontrol agents against R. solani or Sclerotium rolfsii were observed in greenhouse experiments.

The expression of genes involved in parasitism by Trichoderma harzianum is triggered by a diffusible factor

The mycoparasite Trichoderma harzianum has been extensively used in the biocontrol of a wide range of phytopathogenic fungi. Hydrolytic enzymes secreted by the parasite have been directly implicated in the lysis of the host. Dual cultures of Trichoderma and a host, with and without contact, were used as means to study the mycoparasitic response in Trichoderma. Northern analysis showed high-level expression of genes encoding a proteinase (prb1) and an endochitinase (ech42) in dual cultures even if contact with the host was prevented by using cellophane membranes. Neither gene was induced during the interaction of Trichoderma with lectin-coated nylon fibres, which are known to induce hyphal coiling and appressorium formation. Thus, the signal involved in triggering the production of these hydrolytic enzymes by T. harzianum during the parasitic response is independent of the recognition mediated by this lectin-carbohydrate interaction. The results showed that induction of prb1 and ech42 is contact-independent, and a diffusible molecule produced by the host is the signal that triggers expression of both genes in vivo. Furthermore, a molecule that is resistant to heat and protease treatment, obtained from Rhizoctonia solani cell walls induces expression of both genes. Thus, this molecule is involved in the regulation of the expression of hydrolytic enzymes during mycoparasitism by T. harzianum.

[Drug-induced agranulocytosis: clinical study of 19 cases]

Agranulocytosis is one of the most serious side effects to drugs. From January 1991 to June 1996 were diagnosed 19 cases of agranulocytosis associated with drugs at our hospital (incidence rate: 9.4 over million hab. per year). The average age was 62 and 11 cases were women. The drugs most commonly involved were metamizol and ticlopidine. In 15 of the patients fever blew up and 16 presented some infectious location. In 9 of the cases some positive microbiological culture was obtained, gram-negative bacilli being the commonest. G-CSF was used in 13 of the patients, observing a quicker haematological recovery (5.7 days vs 9.1, p = 0.07), though without any difference in mortality, which was of 0%. All this leads to the following conclusions: a high incidence of agranulocytosis in our environment and the important role of metamizol and ticlopidine in its origin.

Cross-clamping of the three hepatic veins in the piggyback technique is a safe and well tolerated procedure

A common stump of the three hepatic veins has always been used to fashion the upper vena cava anastomosis in 205 liver transplantations with the piggyback (PGB) technique performed in our Unit, to avoid outflow problems. The aim was to study the repercussion of lateral inferior vena cava (IVC) clamping on IVC flow and pressure as well as on systemic hemodynamics. We have studied 42 orthotopic liver transplantations performed with the PGB technique. Intraoperative IVC blood flow measurements by transit time ultrasonic volume flowmetry, IVC pressure, and systemic hemodynamics were taken before and after lateral IVC clamping. Graft outflow complications, stenosis or kinking of the upper vena cava anastomosis have not been found in any of the 205 PGB procedures. A significant decrease of IVC flow (23%) and cardiac output (12%) occurred after IVC clamping, whereas mean arterial and central venous pressures were not altered significantly, probably due to an increase (25%) of systemic vascular resistance. Only in one case was an almost total clamping of IVC needed. Venovenous bypass was not needed in any case. Renal perfusion pressure was adequate in all cases. We conclude that the use of a common stump of the three hepatic veins for upper vena cava anastomosis in the PGB technique is safe because any outflow problem of the graft is avoided and, at the same time, is well tolerated hemodynamically because most of the IVC flow is preserved.

[Clinical and laboratory characteristics of patients with pathologic chronic gastroesophageal reflux]

BACKGROUND

Sixty percent of adults has typical symptoms of gastroesophageal reflux in Chile.

AIM

To report the clinical and laboratory features of patients with gastroesophageal reflux.

PATIENTS AND METHODS

Five hundred thirty-four patients (255 male) with gastroesophageal reflux were included in a prospective protocol that included clinical analysis, manometry and endoscopy in all patients, barium swallow in 427, scintigraphy in 195, acid reflux test in 359, 24 h pH in 175, and differential potential of gastroesophageal mucosa in 73 patients.

RESULTS

There was no correlation between the severity of symptoms and the endoscopical severity. Patients with Barret esophagus were 12 years older, were male in a greater proportion and had a higher proportion of manometrically incompetent sphincters than patients with esophageal reflux but without esophagitis or with erosive esophagitis. Severity of acid reflux, measured with 24 h pH monitoring was proportional to the endoscopical damage of the mucosa. There was a close relationship between the mucosal change limit determined with differential potentials and with endoscopy. No short esophagi were found.

CONCLUSIONS

Patients with symptoms of gastroesophageal reflux must be assessed using several objective measures to determine the severity of their pathological alterations.

[Capacity of weight-for-age and length-for-age to predict stunting at 3 years of age]

OBJECTIVE

To compare the capacity of two cut-off points of weight-for-age and length-for-age (-1 and -2 standard deviations) at different ages in the interval between birth and 30 months to predict stunting in three year old children.

MATERIAL AND METHODS

Data from a longitudinal study in Guatemala were used to evaluate the hypothesis that the capacity of cut-off values of weight-for-age and length-for-age to predict stunting at three years of age varies according to age.

RESULTS

Length-for-age at -1 standard deviation (SD) of the WHO/NCHS mean reference values is a satisfactory prognostic indicator of stunting at three years of age during the first semester of life, while the same index at -2 SD is adequate after 9 months of age. Weight-for-age at -1 SD is a suitable indicator only at 9 months and at -2 SD the indicator is satisfactory between 15 and 24 months of age.

CONCLUSION

The capacity to predict stunting at three years of age, for weight-for-age and length-for-age cut-off values varies according to age.

[Energy and nutrient consumption in Mexican women in reproductive age]

OBJECTIVE

To analyze energy and nutrient consumption in Mexican women from 12 to 49 years of age.

MATERIAL AND METHODS

Dietetic information was gathered by a 24 h recall from 9,101 women who participated in the National Nutrition Survey conducted in 1988. These data were compared with sociodemographic and physiologic characteristics. Nutrient consumption was compared with the Recommended Daily Allowances (RDA). Variance analysis and t-test were used to evaluate group differences.

RESULTS

Mean energy consumption was 1,721 kcal per day. The diet consisted of 15% protein, 60% carbohydrates and 25% fat. The proportion of women with dietary intakes lower than 50% of the RDA was 70% for vitamin A, 75% for vitamin B6, 56% for vitamin C, 33% for vitamin B12, 69% for folate, 33% for calcium and 22% for iron.

CONCLUSION

Results show important deficiencies in the diet, predominantly in pregnant and lactating women, in women from low socioeconomic levels and in rural and indigenous women of south of the Mexican republic.

Field evaluation of a diagnostic protocol for Chagas' disease and rangeliosis

The present paper evaluates the protocol for the diagnosis of Chagas' diseases and rangeliosis that is suitable for use in remote and scarcely populated rural areas. Beginning with a blood sample taken by venipuncture in the rural dispensary from 350 inhabitants of Caserío La Sierra, Cojedes State, Venezuela, samples were analyzed at a laboratory located at a distance of 150 Km. Each blood sample was analyzed for blood and clot culture, artificial xenodiagnosis, inoculation into mice, complement fixation reaction (CFR), and indirect fluorescent antibodies test (IFA). Nine isolates of trypanosomes were obtained and identified as Trypanosoma rangeli, 29.4% of the blood samples showed seropositivity for Trypanosoma cruzi, 7.1% of total of persons between 6 and 18 years were found infected with T. rangeli, suggesting active transmission of this trypanosome in an endemic area for Chagas' disease. Results indicate that this protocol of study is reliable, economical and sufficiently versatile to study both rangeliosis and Chagas' disease.