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Biomedical subjects

A Clavel

Publications and source records attributed to A Clavel.

At least 37 records · Page 2Linked to original sources
PubMed1996

Prevalence of Cryptosporidium infections in pigs in Aragón (northeastern Spain).

Faecal samples from 620 pigs randomly selected from 27 farms throughout Aragón were examined to determine the prevalence of Cryptosporidium infections. Detection of oocysts was performed using the ethyl-acetate stool concentration method and the modified Ziehl-Neelsen technique. Cryptosporidium parvum oocysts were identified in 136 (21.9%) pigs from 21 (77.8%) farms. Infected animals ranged from 1 to 6 months old and oocysts were not detected in suckling piglets or adults. Infection rates were significantly higher in weaned, 1-2 month old piglets (59.2%) than in fattening, 2-6 month old pigs (34.3%) (P < 0.001). Cryptosporidial infections were asymptomatic in most of the pigs (90.4%) and usually of low intensity, since 92.6% of the infected pigs excreted few oocysts (0-1 oocysts per field at x 200 magnifications). Although 24.1% of weaned and 5.6% of fattening pigs infected by C. parvum had diarrhoea, it was not found to be statistically associated with infection. In fact, infection rates were higher in non-diarrhoeic than in diarrhoeic pigs, in both weaned (64.7% and 46.7%, respectively) and fattening pigs (34.3% and 33.3%).

Age Factors↗
PubMed1996

Prevalence of Cryptosporidium and Giardia infections in cattle in Aragón (northeastern Spain).

Faecal samples from 554 bovines randomly selected at 30 farms in Aragón were examined to investigate the prevalence of Cryptosporidium and Giardia infections. C. parvum oocysts were identified by using the Ziehl-Neelsen modified technique in 109 (19.7%) bovines ranging from 3 days old to adults. Positive animals were found in 19 (63.3%) farms. As much as 44.4% of calves aged 3-4 days were infected, but infection rates peaked at 6-15 days of age (76.7%). Nevertheless, prevalence was also high in weanling calves aged 1.5-4 months (14%), fattening calves and heifers 4-24 months old (7.7%) and adults (17.8%). Diarrhoea was recorded in 78.6% of suckling and 29.4% of weanling calves infected by C. parvum, but it was only found to be statistically associated with infection in suckling calves (P < 0.01). All calves shedding moderate or many oocysts had diarrhoea, whereas asymptomatic infection was always correlated with few oocysts in faeces. Cryptosporidial infections were always asymptomatic in bovines older than 4 months. Giardia cysts were identified in 65 bovines (11.7%) from 16 (53.3%) of the farms surveyed. Infection rates were significantly higher in suckling (14.1%) and weanling calves (38%) than in bovines older than 4 months (2.2%) (P < 0.001). Diarrhoea was recorded in 45.5% of suckling and 10.9% of weanling calves infected by Giardia, but it was not found to be statistically associated with infection. In fact, infection rates were higher in non-diarrhoeic than in diarrhoeic calves.

Age Factors↗
PubMed1996

Seasonality of cryptosporidiosis in children.

The seasonal distribution of cryptosporidiosis in children in Aragón, a region in northeastern Spain, was determined. Over a period of six years (October 1988 to September 1994), 10,034 stool samples from 4,508 children with gastrointestinal symptoms were analyzed for this purpose. The age of the patients ranged from 1 month to 14 years. Cryptosporidium oocysts were identified in 87 (1.93%) patients. Prevalence was highest (6.20%) in children aged 1 to 3 years old. The prevalence was significantly higher in the autumn-winter period (October to March) than in the spring-summer period (April to September) in the whole population (2.41% vs. 1.35%, p = 0.010) and in the 1- to 3-year-old age group (8.44% vs. 3.20%, p = 0.002), but not in the other age groups. A possible relationship of this pattern to attendance at child care centres is suggested.

Adolescent↗
PubMed1996

Comparison of oocyst shedding and the serum immune response to Cryptosporidium parvum in cattle and pigs.

A comparison was made between oocyst shedding and the presence of specific serum IgG antibodies to Cryptosporidium parvum in 108 bovines and 90 pigs. Oocysts were detected by a commercial immunofluorescence assay in feces from 26.8% of bovines and 34.4% of pigs, whereas positive titers as determined by an indirect fluorescent antibody method were found in sera from 12.9% and 48.9% of the respective animals. Infection was significantly most frequent in suckling calves (82.7%) and weaned piglets (87.5%). By contrast, the numbers of seropositives were highest in weaned calves (17.1%) and fattening pigs (76.6%). The results of coprological and serological analysis corresponded in 65.7% of bovines and 56.7% of pigs. When used to diagnose the shedding of cryptosporidial oocysts, the detection of specific IgG antibodies had a sensitivity ranging from 10.3% (cattle) to 58.1% (pigs) and a specificity of 86.1% (cattle) and 55.9% (pigs).

Animals↗
PubMed1996

Comparison of 2 centrifugation procedures in the formalin-ethyl acetate stool concentration technique for the detection of Cryptosporidium oocysts.

A comparison between the standard formalin-ethyl acetate (FEA) stool concentration procedure (centrifugation at 400 g for 2 min) and a modification proposed to increase the recovery of Cryptosporidium oocysts (500 g for 10 min) was performed on 73 formalin-preserved stool specimens known to be positive for Cryptosporidium. False-negative results were obtained with both methods, but the increase in centrifugation time and force resulted in the detection of a higher number of oocysts and positive samples. The modified procedure had a sensitivity significantly higher than the standard method (99% compared to 86%, P = 0.0045).

Acetates↗
PubMed1996

[Antibiotic resistance in Salmonella enterica: an increasing problem].

OBJECTIVE: To determine the evolution of the frequencies of Salmonella enterica serotypes and their resistance to antimicrobial agents. METHOD: A retrospective study of all S. enterica strains isolated from stool samples in the Hospital Clinico Universitario of Zaragoza over the period 1990-1994. RESULTS: Enteritidis was the most frequently isolated serotype (62.9%), although it showed a progressive decrease (from 76.2% in 1990 to 39.8% in 1994). Typhimurium was the serotype showing the highest resistance levels, 37.1% of its isolates being resistant to ampicillin, streptomycin, chloramphenicol and tetracyclin. There was a distinct increase in the frequency of multiresistant strains, from 9.7% in 1990 to 22.9% in 1994. Of 88 such strains, 78.4% corresponded to serogroup B, whereas only 4.5% to serogroup D. Of the antimicrobial agents traditionally considered elective, only cotrimoxazole maintained acceptable resistance levels (4.4%). Resistance to fluoroquinolones or 3rd-generation cephalosporines was not detected. CONCLUSIONS: The increasing frequency of Typhimurium, a highly resistant serotype, restrains the elective antimicrobial agents to cotrimoxazole in children and fluoroquinolones in adults. 3rd-generation cefalosporines may be a good alternative in case of therapeutic failure.

Drug Resistance, Microbial↗
PubMed1995

Occurrence of blastocystis sp. in cattle in Aragón, northeastern Spain.

The occurrence of Blastocystis sp. in cattle is reported herein for the first time in Spain. Stool samples from 554 bovines ranging from 3 days old to adults collected from 30 cattle farms in Aragón (northeastern Spain) were concentrated by the formalin-ethyl acetate method and examined light microscopically for the presence of gastrointestinal parasites. Vacuolated cells of Blastocystis sp. was detected in fecal specimens from 10 calves (1.8%) aged from 7 weeks to 6 months. Infected calves were detected at 3 of the 30 farms surveyed (10%). Blastocystis sp. cells were rounded or oval, with a diameter ranging from 6.25 to 15 microns. Blastocystis infection in cattle was never correlated with diarrhea, although infection intensities were generally low.

Animals↗
PubMed1995

Evaluation of the optimal number of faecal specimens in the diagnosis of cryptosporidiosis in AIDS and immunocompetent patients.

This study determines the optimal number of faecal samples that should be examined in order to minimize the occurrence of false-negative results in the diagnosis of cryptosporidiosis using routine techniques. A total of 23,023 faecal samples from 10,870 patients submitted for parasitological examination were processed by the formalin-ethyl acetate concentration technique and stained using a modified Ziehl-Neelsen method. Cryptosporidiosis was diagnosed in 232 patients (2.13%), 44 of whom were infected by HIV, the prevalence rate in this population group being 15.54%. The increase in the number of diagnoses obtained by the examination of n and (n-1) specimens was evaluated statistically. This study found that three is the optimal number of faecal samples that should be examined when cryptosporidiosis is suspected in immunocompetent patients; whereas, only two samples are required for diagnosing this protozoosis in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Detection of Blastocystis sp. in pigs in Aragon (Spain).

Infection by Blastocystis sp. has been detected for the first time in pigs in Spain. Detection was carried out by the ethyl acetate-formalin concentration method and direct microscopy. Vacuolated cells of Blastocystis sp. were found in stool samples from 27 of 360 pigs examined (7.5%). The protozoan was present on nine of 17 pig farms studied (53%). Infected pigs ranged from 1 month old to adults, but the organism was most frequent in 1-2 month old (18.4%) and 2-6 month old pigs (15.4%). No correlation was found between Blastocystis sp. infection and occurrence of diarrhoea in pigs.

Age Factors↗
PubMed1995

Detection of Cryptosporidium oocysts in extra-intestinal tissues of sheep and pigs.

Extra-intestinal infections by Cryptosporidium parvum have been detected in pigs and sheep. Detection was carried out by imprints of the mucosa of different organs and viscera in 55 sheep and 57 pigs slaughtered at three abattoirs in Zaragoza (northeast Spain). Imprints were stained by using a modified Ziehl-Neelsen technique. In addition to intestinal infections, cryptosporidial oocysts were found in the gall-bladders of two pigs which were 2 months old, and in some organs of sheep aged 5 days or more, including the gall-bladder (5), mesenteric lymph nodes (2), trachea (7), lung (3) and the uterus of one lamb.

Animals↗
PubMed1991

[Expediency of hospital admission for acute diarrhea syndrome in a short-stay unit].

We present the results of a 187 cases acute diarrhea study managed in the Short Stay Unit of Clinic Universitary Hospital of Zaragoza during 1987-1988. To that aim, we designed an actuation protocol which included the gathering of several data, the realization of complementary studies and the evolutive pursuit. The coproculture resulted positive in a 54.5% of cases and Salmonella was the microorganism more frequently isolated. Most of the species were sensible to common antibiotics and all of them sensible to norfloxacin. Nearly a third part of patients developed some kind of complication. Therefore we infer that acute diarrhea may be subsidiary of diagnosis and treatment in Short Stay Units.

Acute Disease↗
PubMed1991

[Epidemiology of shigellosis and colicin typing of Shigella sonnei. A 14-year study].

To study the most important epidemiologic features of shigellosis and the application of colicinotyping as an epidemiologic marker for Shigella sonnei. A total of 44.818 stoll-cultures were performed. We classify, using colicinotyping, 156 Shigella sonnei strains isolated from different patients. The incidence of Shigellosis in our media is low (1.08% of all stool-cultures). It is more frequent in pediatric population and increases on late summer and fall. We had been able to show an increasing incidence, with an hyperendemic situation during a three-years period (1981-1983). Shigella sonnei is the most prevalent species (86% of cases), followed by S. boydii (7.3%) and S. flexneri (5.9%). All S. sonnei strains epidemiologically related showed the same colicinotype. Only two strains were not typable and we identified 9 different colicinotypes, being type 13 (30.8%), type 8 (18.6%), type 6 (17.3%) and type 12 (11.54%) the more frequent types. Colicinotype 8 was the more prevalent between 1978-1979. Type 13 was predominant between 1981 and 1985. During 1987 and 1989, at the same time that incidence had risen, types 6 and 12 were prevalent. The total number of different colicinotypes identified during a single year is never greater than five. Colicinotyping of S. sonnei is a simple typing method that gives enough useful epidemiologic information, discriminative and reproducible. Although there are changes of circulating types incidence and the prevalen colicinotype colud vary from one year to another, during longer periods of time there is a reduced number of alternating colicinotypes, which sets up a situation that could be further classified as endemic.

Adult↗
PubMed1989

[Intestinal infections caused by Aeromonas].

We have identified 38 instances of intestinal infection by Aeromonas and 4 by Plesiomonas in 16,184 coprocultures carried out during a 4 year period in the HCU of Zaragoza. The low prevalence can be related with the fact that specific media for the recovery of these organisms were not used. The species Aeromonas sobria (47.36%) and A. caviae (39.47%) were more common than A. hydrophila (13.15%). Aeromonas were isolated from patients with and without intestinal disease. The occurrence of gastrointestinal disease was independent from the type of Aeromonas species isolated (p greater than 0.1). We did not find significant differences when we compared patients with and without diarrhea, the rates of the strains that produced gas from glucose, and those of the strains that did not produce arabinose acid. The rates of positivity for lysine decarboxylase and Voges-Poskauer were significantly more common in the strains isolated from symptomatic patients. The sensitivity to cephalothin (MIC less than or equal to 8 micrograms/ml) can be an adequate marker to differentiate A. sobria from the other two species (p less than 0.01).

Aeromonas↗
PubMed1988

[Retrocecal mucus-secreting tumors of the appendix (mucoceles). Apropos of 3 radiologically diagnosed cases].

The term of appendiceal mucocele has been applied to a group of lesions distending the lumen of the appendix; filled with mucus. About 15% of these lesions are malignant tumors (cystadenocarcinomas). All these lesions may lead to pseudomyxoma peritonei, but only the peritoneal involvement due to a malignant tumor (adenocarcinoma) has multiple recurrences and poor prognosis. Benign lesions are cured by appendicectomy, even if a peritoneal "gelatinous" effusion is present. These lesions can usually be early diagnosed by US and CT features if the mucocele extends behind the cecum in the retroperitoneal space, especially if the wall is calcified. A colic examination (with barium enema or colonoscopy) must be taken event if the diagnosis is made by US or CT means, because of the significant association of mucocele with other colonic tumors.

Adult↗
PubMed1987

The renin-angiotensin system is not responsible for hypertension following coronary artery bypass grafting.

Systemic hypertension following coronary artery bypass graft (CABG) procedures has been reported to occur in 15% to 80% of cases. Previous reports have implicated the renin-angiotensin system as being responsible, at least in part, for this phenomenon. In this prospective study, 18 previously normotensive subjects were studied before, during, and after CABG. In 4 patients (22%), paroxysmal postoperative hypertension developed (systolic blood pressure greater than 150 mm Hg). There were no differences between the normotensive and hypertensive groups in plasma renin activity, angiotensin II level, or aldosterone level. Despite the trend toward elevation of these variables during cardiopulmonary bypass (CPB), all had returned to control levels within two hours after CPB, whether or not hypertension developed. Serum norepinephrine levels were elevated (.10 greater than p greater than .05) in the hypertensive group at the time hypertension developed. No other relationship or pattern could be defined to distinguish the hypertensive from the normotensive group. The renin-angiotensin system does not appear to be responsible for paroxysmal hypertension following CABG.

Adult↗
PubMed1987

[Cryptosporidiosis in childhood].

Recent application of resisting acid-fast staining techniques for parasitologic investigation has allowed cryptosporidiosis to acquire an apparent interest, mainly caused by its apparition in immunosuppressed patients, specially when they have AIDS. More recently cryptosporidiosis has been reported in immunocompetent persons whose illness, stated as acute diarrhea, is mild and self-limited. In this article we report a prospective study of a series of 36 children with cryptosporidiosis. Most of them had acute diarrhea and six were asymptomatic. Other microorganisms were found associated with Cryptosporidium in 9 cases (6 had Giardia lamblia). Period of elimination of parasite was greatly uncertain. Symptomatic treatment was performed in patients with pure cryptosporidiosis. Favourable evolution was assessed in all cases.

Adolescent↗