PubMed Health⌕ Search

Biomedical subjects

J M García-Arenzana

Publications and source records attributed to J M García-Arenzana.

At least 19 recordsLinked to original sources
PubMed2003

[Incidence of bacterial translocation in four different models of experimental short bowel syndrome].

UNLABELLED: The outcome of patients with short bowel syndrome is influenced for factors such as the length of remnant intestine or the presence or absence of ileocecal valve (ICV). Gram-negative sepsis, the main cause of mortality in this group of children, is probably due to bacterial translocation (BT), because after gut resection there are a number of circumstances that favour its occurrence, being the most known intestinal dismotility, bacterial overgrowth, loss of gut-associated lymphoid tissue, total parenteral nutrition (TPN) and fasting related mucosal atrophy. The aim of this experimental controlled study was to test the incidence of BT after four different types of gut resection, in animals fed orally or receiving TPN. Hundred and three adult Wistar rats bred and raised in our facilities according to European Union Regulations were randomly divided in six groups:--Group 1 (n = 26): non-manipulated animals, served as a control.--Group 2 (n = 14): 80% non-lethal small bowel resection, fed orally.--Group 3 (n = 15): same resection as group 2 but including ICV. Rat chow ad libitum.--Group 4 (n = 27): non-resected fasting animals receiving all-in-one TPN solution.--Group 5 (n = 11): same resection as group 2, but fasting and receiving TPN--Group 6 (n = 10): 90% small bowel resection, including cecum and ICV, fasting and TPN. The animals were maintained for 10 days in individual metabolic cages, and, at the end of the experiment, were bled by portal and cardiac puncture. Mesenteric lymph nodes, peripheral and portal blood samples were cultured for BT. Non-manipulated rats (group 1) had lower BT incidence (8%) than resected ones (groups 2, 3, 5 and 6, 93%, 60%, 91%, 60%, p < 0.05) or animals non-resected, receiving TPN (group 4.51%, p < 0.05). When resection included ICV in orally fed rats BT index was also lower (group 3 vs group 2.60% vs 91%, p < 0.05). In TPN resected animals a drop was also found in BT when ICV and cecum were added to small bowel resection (group 6 vs group 5.60% vs 91%, p < 0.05). IN CONCLUSION: 1. Gut resection is associated to a high degree of BT, even if the animals are fed orally. 2. Resection including ICV, produced less BT. 3. TPN-related BT was shown in half of the animals non resected. 4. TPN-resected rats had also less BT when ICV and cecum were removed.

Animals↗
PubMed2002

[Epidemiology of invasive pneumococcal disease in children in Gipuzkoa (Spain) from 1981 to 2001].

OBJECTIVES: To assess the epidemiological characteristics of invasive pneumococcal disease (IPD) in children in Gipuzkoa (Spain) as well as the serotype distribution among these episodes and to analyze the potential impact of new conjugate vaccines. METHODS: We performed a retrospective study of cases of IPD in the pediatric population (< 15 years) between 1981 and 2001. Patients were included if blood, cerebrospinal, joint or peritoneal fluid isolates were culture-positive for Streptococcus pneumoniae. RESULTS: One hundred twenty-nine episodes (30 meningitis, 39 bacteremic pneumonia, 7 peritonitis, 1 arthritis and 52 bacteremia without focus) were identified. The incidence of IPD in children increased throughout the study period and from 1999-2001 was 12.6 cases per 100,000/ year in children aged < 15 years, 34.5 in those < 5 years, 48.4 in those < 2 years and 40.8 in infants < 2 months. The incidence of pneumococcal meningitis was similar throughout the study period (1981-2001): 1.3 in children aged < 15 years, 3.5 in those < 5 years, 8.1 in those < 2 years and 10.2 in infants < 2 months. From 1989 to 2001 mortality was 1 % (1/98 cases). The pneumococcal serotypes and serogroups present in the 7-valent vaccine accounted for 60.5 % and 70.9 % of the cases (9-valent vaccine: 70.2 % and 80.6 %; 11-valent vaccine: 76.6 % and 87.2 %). From 1999-2001, penicillin resistance was 35.4 % and erythromycin resistance was 38.7 %. CONCLUSIONS: The incidence of IPD in children in Gipuzkoa has increased in the last few years, with rates similar to those in other European countries. Continued surveillance is required to assess the impact of the new conjugate vaccines on this infection.

Adolescent↗
PubMed2002

[Beneficial effects of Bifidobacterium lactis in the prevention of bacterial translocation in experimental short bowel syndrome].

BACKGROUND: Probiotics are live organisms that survive passage through the gastrointestinal tract and have beneficial effects on the host. Lactobacillus and Bifidobacterium have been recommended in cholesterol lowering, acute diarrhea, prevention of cancer or inflammatory bowel disease. On the other hand, after massive bowel resection bacterial overgrowth is frequent and favours the occurrence of bacterial translocation (BT). The possible beneficial effects of Bifidobacterium lactis (BL) administration on BT in experimental short bowel syndrome (SBS), have not been investigated. AIM: To test the hypothesis that BL administration decreases BT in SBS in animals fed orally. METHODS: Thirty-two adult Wistar rats fed orally with standard rat chow and tap water "ad libitum" were maintained individual metabolic cages for ten days after 80% gut resection from the duodeno-jejunal angle to 10 cm above the cecum and divided in two groups: -Group A (n = 14): served as control. -Group B (n = 18): daily 7.8 x 109 CFU Bifidobacterium lactis administration, after orgastric intubation. At the end of the experiment they were sacrificed and mesenteric lymph nodes (MLN), and peripheral and portal blood specimens were recovered and cultured. Bacterial identification in blood was made by conventional methods and MLN culture was considered positive with a growth over 100 CFU/g. RESULTS: Bacterial translocation was detected in 93% of Group A rats. The incidence of BT in Group B was 44%. The relative risk reduction (RRR) was 0.52 (95% confidence interval 0.23-0.81) and the number needed to treat (NNT) was 2 (95% confidence interval between 1-5). CONCLUSION: Administration of Bifidobacterium lactis reduces the incidence of BT in adult Wister rats, after 80% gut resection.

Animals↗
PubMed2001

[Effect of various trophic factors on bacterial translocation in experimental short bowel syndrome].

Massive bowel resection triggers an adaptive process in the remaining intestine in spite of which, bacterial translocation (BT) is frequent under these conditions. Several trophic factors, including growth hormone (GH), epidermal growth factor (EGF) and insuline (INS) are involved in the process of adaptation in short bowel syndrome (SBS). However, the effect of GH, EGF or INS on BT has not been investigated experimentally. The aim of the study was to test the hypothesis that GH, EGF or INS administration prevents BT in rats with SBS receiving only parenteral nutrition (PN). Thirty-seven adult Wistar rats underwent central venous cannulation and were randomly assigned to one of two groups receiving for ten days four treatment regimes: PN group (N = 10) fasting, all-in-one PN solution (300 mL/kg/24 h, 280 kcal/kg/24 h), 80% gut resection including ileo-cecal valve. GH group (N = 9) fasting, same PN regime and resection plus GH (1 mg/kg/d, s.c.). EGF group (N = 9): same PN regime and resection plus EGF (150 microgr/24 h, e.v.) INS group(N = 9): same PN regime and resection plus INS (1 U.I./100 g/24 h s.c.) At the end of the experiment the rats were exanguinated and mesenteric lymph nodes and samples of systemic and portal blood were obtained and cultured. Several samples of full-thickness jejunal wall were taken for measuring cell proliferation index (PCNA) and mucosal thickness. Jejunal mucosal thickness increased by 30%, 28% and 29% and PCNA index by 21%, 20% and 25% in GH, EGF and INS, treated rats respectively in comparison with those treated with PN alone. However, contrary to our expectations, BT expressed by positive culture of intestinal germs in systemic blood was demonstrated respectively in 44%, 40% and 28% of GH, EGF and INS animals, respectively, and in 0% of PN-only rats. Although exogenous GH, EGF or INS improves gut mucosal structure in rats with SBS treated with PN, it seems to increase rather than decrease mucosal permeability to intestinal germs in them.

Animals↗
PubMed2001

[Bacterial translocation associated with short bowel: role of ileocecal valve and cecum].

Sepsis in short bowel syndrome (SBS) is due in part to bacterial translocation (BT). Parenteral nutrition (PN) is often necessary in SBS and promotes BT. The presence of ileocecal valve (ICV) has been considered as a good prognostic factor in the outcome of this children. The aim of this study was to asses the effect of the presence or absence of ICV and cecum in five different models of gut resection in the rat. Fifty-five adult Wistar rats were randomly assigned to one of five groups: Group 1 (N = 14): standard rat chow + 80% small bowel resection. Group 2 (N = 10): standard rat chow + 80% small bowel resection including cecum. Group 3 (N = 10): standard rat chow + 80% small bowel resection including ICV. Group 4 (N = 11): NP + 80% small bowel resection. Group 5 (N = 10): NP + 80% small bowel resection including ICV and cecum. Ten days after surgery they were sacrificed and mesenteric lymph nodes (MLN), spleen and peripheral (PBL) and portal blood (POBL) specimens were recovered and cultured. Groups 3 (without ICV, with cecum) and 5 (without ICV, without cecum) showed 60% BT in MLN and POBL, and groups 1 and 4 (with ICV, without cecum) 93% and 91% respectively (p < 0.05). In PBL, group 3 (without ICV, with cecum) showed also less BT than groups 1 and 4 (10% vs 43% and 55% respectively, p < 0.05) and group 5 (without ICV and cecum) had less BT than groups 1, 2 and 4 (0% vs 43%, 30% and 55%, p < 0.01). In conclusion, these results suggest that the absence of ICV decreases BT and that the cecum does not seems to play a role on his.

Animals↗
PubMed1998

In-vitro, in-vivo and ex-vivo studies with oral beta-lactams against Streptococcus pneumoniae.

In-vitro killing curves, a protection model in immunocompetent mice and an ex-vivo model in volunteers were used to evaluate the efficacy of amoxycillin, cefuroxime axetil and cefpodoxime proxetil against a penicillin-intermediate-resistant Streptococcus pneumoniae (MIC = 1 mg/L) (PRP) and a penicillin-susceptible S. pneumoniae (MIC = 0.01 mg/L) (PSP). In vitro, the maximal bactericidal activity was obtained with amoxycillin (1 x MIC versus 2 x MIC cefpodoxime and 4 x MIC cefuroxime). Mice were challenged by intraperitoneal inoculation and treated orally every 8 h for 48 h with 2.5, 5, 7.5 and 10 mg/kg doses of these three beta-lactams. The rate of survival for the PSP strain was 100% with any dose of the three tested antibiotics. For the PRP strain only amoxycillin showed 100% survival with 5, 7.5 or 10 mg/kg doses. Twelve healthy volunteers were randomized in three groups and each received two doses of the oral antibiotic. Blood samples were collected from each subject 0.5 h and 2 h after drug administration and serum inhibitory and bactericidal titres were measured. Similar values were obtained with the three beta-lactams against PSP but against PRP only the serum of volunteers that had taken amoxycillin exhibited serum bactericidal titres of > or = 8. This study suggests a more predictable therapeutic efficacy against pneumococcal infection with amoxycillin than with available oral cephalosporins.

Administration, Oral↗
PubMed1993

Ten-year survey of quinolone resistance in Escherichia coli causing urinary tract infections.

In a ten-year survey (1983-1992) of quinolone resistance in Escherichia coli causing urinary tract infections in a general practice patient population, 9,934 strains were tested. Resistance increased remarkably from 1989 onwards. The rate of resistance to pipemidic acid was < or = 6% before 1989 and 18% in 1992; the rate of resistance to ciprofloxacin (MIC > or = 4 mg/l) was 0.8% in 1989 and 7.1% in 1992. Although the consumption of older quinolones decreased the total consumption of quinolones increased yearly.

Anti-Infective Agents↗
PubMed1993

[The indications for the antipneumococcal vaccine in Spain].

The anti-pneumococcal vaccine, with 23 capsular polysaccharides, is an effective vaccine used in most of the developed countries, although still not commercially available in Spain. Between January 1981 and June 1992, we isolated 784 Streptococcus pneumoniae from clinical samples (excluding asymptomatic carriers), 728 of which could be serotyped (300 isolated in hemoculture and/or LCR). 91.5% of the total and 93.3% of the most invasive strains, as well as 98.1% of the penicillin-resistant strains or 98.8% of the isolated multiresistant strains, presented a serotype covered by the current vaccine. The high resistance to antibiotics of the pneumococcus in Spain makes more urgent the indication of the vaccine in our community.

Bacterial Vaccines↗
PubMed1992

[Pulmonary infection caused by Rhodococcus equi in a renal transplant recipient].

Rhodococcus equi is a primarily pathogen in animals and it has only rarely been seen in immunocompromised humans. We describe our experience with an HIV-negative patient with a functioning renal graft under cyclosporin-azathioprine-prednisone therapy. The patient died after a two months recurrent multifocal pneumonia. The cultures from sputum and blood were negatives but R. equi was isolated from lungs in the necropsy. Most of the 41 cases we had found in the literature had AIDS or HIV infection. Six cases had a kidney graft under azathioprine-prednisone therapy. Rhodococcus equi infection may be missed in some instances due to incomplete or improper identification of the organism, that grows well in aerobic media but is usually regarded as a component of normal flora or as a contaminant. The ability of R. equi to persist in and eventually to destroy macrophages is the basis of its pathogenicity. It also explains the clinical resistance to antibiotics without intracellular activity. Rhodococcus equi infection must be suspected in immunocompromised patients with recurrent pneumonia. Correct identification and combined therapy with lipophilic antibiotics that penetrate the macrophages are necessary to prevent the high mortality of this infection.

Actinomycetales Infections↗
PubMed1992

[Peritoneal pneumococcal infections].

The clinical-microbiological characteristics of 13 patients iun whom Streptococcus pneumoniae (Pneumococcus) was isolated from the peritoneum over eight and a half years in a third grade hospital are reviewed. It is noteworthy the fact that only in 7 cases primary or spontaneous peritonitis were treated; the remaining cases were secondary to perforation or genital infection in females. The presence of antibiotic resistance in pneumococcus was high and global mortality was low.

Adolescent↗
PubMed1992

[Rhodococcus equi in HIV infected patients: 2 new cases].

We reported two HIV infected patients with bacteremia and pneumonia due to Rhodococcus equi. None of them had suffer any opportunistic infection before this episode. Clinical presentation includes respiratory tract symptoms of subacute onset and fever. The X-ray examination in both cases revealed pneumonia and lung abscess in upper lobes as well as lung infiltrates in other lobes. The microorganism was isolated in lung fine needle aspiration, bronchoalveolar lavage and blood cultures in both cases. One patient died and the other was under antibiotic treatment 5 months after discharge. The therapeutic options in this infection must include the use of at least two different antibiotics to which the microorganism is sensitive, and for a prolonged period of time. Surgical treatment should be considered if the evolution is poor.

Actinomycetales Infections↗
PubMed1991

[Resistance to erythromycin in Streptococcus pneumoniae].

A total of 640 S. pneumoniae isolates from different clinical samples obtained from patients (not including carriers) over a 10 years period were studied. Global resistance to erythromycin (MIC greater than or equal to 1 microgram/ml) was 9.1% (8.1% with MIC greater than or equal to 8 micrograms/ml). Resistance was more prevalent in serotypes 6, 14, and 19, either in absolute number or in relation to the total number of strains in each serotype. A total of 16% of strains isolated from ear fluid specimens and bronchial secretions were resistant, but only a 4.5% of blood culture isolates showed also resistance to erythromycin. Resistance was found more frequently on pediatric patients. Although the highest resistance rate was found during the last year (15% of all 1990 isolated strains or 13.9% if the period also includes the first 1991 quarter) we did not find a gradual increase over time. Most of the resistant strains showed also resistance to tetracycline and other antimicrobial agents. Overall, 94.8% of strains showed multiple resistance (combined resistance to at least 2 other different antibiotics, not including clindamycin resistance, which always matches erythromycin resistance), and 60.3% showed resistance to penicillin. The multiply-resistant pattern and the similarity of isolated strains suggest an epidemiologic behaviour that not necessarily has to be linked to higher erythromycin use.

Adult↗