[Adaptation in the small intestine: Effect of minimal enteral nutrition and probiotics on proliferation and apoptosis in the intestinal wall]. / Adaptación en el intestino corto: efecto de la nutrición enteral mínima y los probióticos sobre la proliferación y la apoptosis en la pared intestinal.

BACKGROUND: The intestinal wall integrity is central to the barrier function and depends on the balance of proliferation/apoptosis. Short bowel (SB) or Parenteral Nutrition (PN) induce high bacterial translocation (BT) probably by the intestinal barrier bug. Probiotics or minimal enteral nutrition (MEN) have reduced BT in animal models. OBJECTIVE: Determine in two BT animal models (SB or PN) the effect of MEN or probiotics on proliferation and apoptosis rates of the intestinal wall. METHODS: Seventy-one Wistar rats, divided into 4 groups: 1) PN (N = 23): parenteral nutrition; 2) PNMEN (N = 16): PN + MEN (2.9 g/100 g/day standard diet); 3) RES (N = 15): 80% bowel resection and standard oral diet; 4) RESPROB (N = 17): RES + probiotics (7 X 10(9) CFU Bifidobacterium lactis). After 10 days in metabolic cages, mesenteryc lymph nodes, portal blood and peripheral blood were cultured. By immunohistochemistry, proliferation and apoptosis index were calculated as well as the proliferation-apoptosis rate. RESULTS: BT: decreased in PNMEN (45%) and RESPROB groups (35%) versus PN (65%) and RES (67%) groups (p<0.05). Proliferation index: was better in PNMEN (12,07) and RESPROB (13,93) groups than PN (7,45) and RES (5,54) groups. (p

[Detection of bacterial translocation by polymerase chain reaction in an experimental short bowel model]. / Diagnóstico de la translocación bacteriana en el intestino corto experimental mediante reacción en cadena de polimerasa.

BACKGROUND: Bacterial overgrowth occuring after massive bowel resection, facilitates Gram-negative intestinal Bacterial Translocation (TB). Probiotic agents might have beneficial effects on TB. On the other hand, polymerase chain-reaction (PCR) has better sensitivity than conventional methods for bacterial detection and has not been investigated in experimental models of short bowel syndrome and TB. OBJECTIVE: To test the hypothesis that the administration of Bifidobacterium lactis (BL) decreases Escherichia coli Bacterial Translocation (ECTB) in experimental short bowel syndrome and to confirm the better sensitivity of PCR technique to detect ECTB. METHODS: Adult Wistar rats, orally fed with standard rat chow and tap water "ad libitum", were maintained in individual metabolic cages for ten days and divided into three groups: Control (n = 15): non-manipulated animals. RES (n = 15): 80% gut resection. Daily administration 1 ml of sterile water, after orogastric intubation. RES-PRO (n = 18): same resection and daily administration of 7.8 x10(9) Bifidobacterium lactis Colony Forming Units (CFU). At the end of the experiment, mesenteric lymph nodes (MLN), and both peripheral and portal blood samples were recovered and cultured by standard procedures. Also, genomic DNA from E. coli was detected by PCR technique. RESULTS: By conventional cultures ECTB was detected in 0% in the control group, 73% in the RES group and 33% in the RES-PRO group. PCR technique detected ECTB in 47% of the control group, 87% of the RES group and 33% of RES-PRO group, showing higher sensitivity. By both methods, animals receiving BL (RES-PRO group) showed less ECTB. By conventional culture, the relative risk (RR) was 0.45 (95% CI 0,22-0,79) and the number needed to treat (NNT) was 3 (95% CI 0-11). By PCR technique, the RR was 0.38 (95% CI 0.19-0.76), and the NNT 2 (95% CI 0-4). CONCLUSIONS: 1) Administration of Bifidobacterium lactis reduces the incidence of ECTB. 2) PCR technique is a more sensitive method for ECTB detection.

[Short bowel syndrome in the research setting: 15 years' experience]. / El síndrome de intestino corto en el ambito experimental: experiencia de 15 años.

The fight against infection and liver disease associated with parenteral nutrition (PN) are surely two of the most problematic aspects in the management of paediatric patients with short bowel syndrome (SBS). In the Research Unit of Donostia Hospital, we have spent the past 15 years investigating different ways of reducing these complications in an experimental model of short bowel in the Wistar rat (resection of 80% of the small bowel, with and without PN). All the experiments had a duration of 10 days and 323 animals reached the end of the study period. Nine groups were established in which some type of intervention was performed, and there were 8 control groups. The interventions were: 3 dietary (minimal enteral nutrition [MEN] with low or high dose probiotics); 5 pharmacological (administration of growth hormone [GH], epidermal growth factor [EGF], insulin, cholecystokinin [CCK], and selective intestinal decontamination [SID]); and 1 surgical (resection of the ileocaecal valve). Infection due to bacterial translocation (BT) was detected by culture of mesenteric lymph nodes, portal blood and peripheral blood, and liver damage by the levels of proinflammatory cytokines (IL-1 and TNF-alpha). In summary, our results are: Probiotics, MEN and SID reduce BT. Liver damage was milder in the groups with MEN, SID and CCK. The groups receiving GH, EGF or insulin presented a higher incidence of BT. BT was lower after resection of the ileocaecal valve. In conclusion, the probiotics, MEN and CCK could be useful in the management of children with SBS. These data confirm the utility of this experimental model of short bowel for the investigation of different aspects of SBS.

[Effect of the administration of cholecystokinin on the cholestasis associated with total parenteral nutrition in experimental short bowel]. / Efecto de la administración de colescistoquinina sobre la colestasis asociada a la nutrición parenteral total en el intestino corto experimental.

INTRODUCTION: Total parenteral nutrition (TPN) is not free of complications. One of the most serious is cholestasis; the cause of this complication is unclear but it may be due to a lack of an enteral stimulus for cholecystokinin (CCK) production. CCK is essential for contraction of the gallbladder and also stimulates intrahepatic bile flow. Its absence may contribute to cholestasis. After any hepatic aggression, the Kupffer cells respond and release proinflammatory cytokines, such as interleukin-1 (IL-1) and tumour necrosis factor alpha (TNF-alpha), which increase the hepatic damage. The objective of this experimental study has been to observe the effect that the exogenous administration of CCK could have on hepatic damage in experimental short bowel with and without TPN, determined using the serum levels of IL-1 and TNF-alpha. MATERIAL AND METHODS: A resection of 80% of the small bowel was performed on 53 Wistar rats and a continuous infusion of saline or TPN was initiated. The rats were divided into the following groups: SHAM (N = 14): normal saline infusion and free access to food and water. TPN (N = 15): Standard TPN. SHAM-CCK (N = 14): same as the SHAM group but with a daily dose of CCK. TPN-CCK (N = 10): same as the TPN group but with a daily dose of CCK. At the end of the experiment, the animals were sacrificed and blood samples were obtained to determine the IL-1 and TNF-alpha values by ELISA. RESULTS: The IL-1 and TNF-alpha levels were higher in the TPN group (7.537 and 5.899 pg/mL, respectively) than in the SHAM group (6.509 and 4.989 pg/mL, respectively) (p > 0.05). The TNF-alpha values were higher in the SHAM group (4.989 pg/mL) than in the SHAM-CCK group (4.583 pg/mL) (p < 0.001). The IL-1 and TNF-alpha levels were higher in the TPN group than in the TPN-CCK group (6.709 and 4.794 pg/mL, respectively) (p < 0.001 for TNF-alpha). CONCLUSIONS: 1. There is a rise in the serum levels of the pro-inflammatory cytokines IL-1 and TNF-alpha in animals with short bowel on TPN or enteral nutrition. 2. The administration of CCK causes a fall in the IL-1 and TNF-alpha levels, and could be used such as a further measure to prevent TPN-associated cholestasis.

[Selective intestinal decontamination and parenteral nutrition related liver disease. Experimental study]. / Descontaminación intestinal selectiva y hepatopatía asociada a nutrición parenteral: estudio experimental.

Selective intestinal decontamination (SID) has been useful restraining Bacterial translocation (BT) in both animal models and human clinics. The not well known parenteral nutrition-related liver disease is a serious problem associated to short bowel and long-term parenteral nutrition (PN) use, and BT is also frequent in those patients. Germs reach liver through portal vein and activate Kupffer cells, which release cytokines as IL-1 or TNF-alpha. The aim of this study was to test the use of SID restraining BT in a PN undergoing experimental short bowel model, and its possible favourable consequences on hepatic injury determined by IL-1 and TNF-alpha levels. Twenty-five 240-280 g Wistar rats were divided into two groups and maintained in individual metabolic cages for ten days: Resection-PN group (n=15): animals with a bowel resection of the 80% and a continuous PN infusion. Resection-PN-SID (n=10) group: similar to previous group and a daily oral administration of Tobramycine (20mg/kg/day) and Polymyxine-E (25mg/kg/day). Animals were sacrificed and mesenteric lymph nodes (MLN), and both peripheral and portal blood samples were recovered for TB determination in bacterial culture. Determination of both IL-l and TNF-alpha seric levels were carried out by ELISA. Bacterial translocation incidence was higher in RES-NPT group (66.6%) than RES-NPT-SID group (30%) (P>0,05). The relative risk was 2.22 (IC 95% 0,81-6,11) and the number needed to treat was 3 (IC 95% 2-235). Seric levels of IL-1 and TNF-alpha were also higher in RES-NPT group (7,537 and 5,399 pg/ml, respectively) than in RES-NPT-SID group (6,397 and 5,032 pg/ml respectively) (p<0,001). 1. SID reduces TB in a PN undergoing experimental short bowel resection murine model. 2. Parenteral nutrition-related liver disease decreases in DIS receiving animals.

[Necrotizing enterocolitis and bacterial translocation: role of minimal enteral nutrition]. / Enterocolitis necrosante y traslocación bacteriana: papel de la nutrición enteral mínima.

INTRODUCTION: Both necrotizing enterocolitis (NEC) and bacterial translocation (BT) have in common that bacterial overgrowth, a decrease in immunity and intestinal mucosal damage, followed by a barrier failure, can act as trigger factors. The main objectives in NEC treatment are to reduce mortality due to sepsis and to promote feeding tolerance. To achieve that, Minimal Enteral Nutrition (MEN) (less than 25% of the calories provided by enteral route) is a more and more used technique in newborns who receive Parenteral Nutrition (PN) to slow down fasting related villi atrophy and to attenuate its consequences. AIM: To test the hypothesis that MEN decreases BT in an experimental model of PN. METHODS: Twenty-four adult Wistar male rats received a continuous infusion of all-in-one PN solution through a jugular vein catheter. The animals were randomly divided in two groups and maintained in individual metabolic cages for ten days. * Control group (N= 1): fasting rats receiving, standard PN (300 mL/kg/ 24 h, 280 kcall kg/24 h). * MEN group (N=13): standard PN and rat chow (15 g /24 h, 3,1 kcal/g). At the end of the experiment animals were sacrificed and mesenteric lymph nodes (MLN), and both peripheral and portal blood samples were recovered and cultured. Bacterial identification in blood was carried out by conventional methods and MLN culture was considered positive with a growth over 100 Colony Forming Units/g. RESULTS: Weight curve was better in MEN group and BT was also significantly reduced. Translocation was found in 45% of control group and 8% of MEN group (p < 0,05). The relative risk (RR) was 5,9 (IC 95% 0,81-43,71) and the number needed to treat (NNT) was 3 (95% CI 2-20). CONCLUSIONS: 1. MEN reduces the incidence of BT in an experimental model of parenteral nutrition. 2. BT reduction could decrease NEC-related sepsis risk.

Effect of growth hormone, epidermal growth factor, and insulin on bacterial translocation in experimental short bowel syndrome.

BACKGROUND/PURPOSE: An adaptive process starts in the remaining intestine after massive resection, and several trophic factors including growth hormone (GH), epidermal growth factor (EGF), and insulin (INS) have been shown to have a positive effect on it. Bacterial translocation (BT) is frequent after extensive small bowel resection, but the effects of GH, EGF, or INS have not been investigated in experimental short bowel syndrome (SBS). This study tests the hypothesis that GH, EGF, or INS decrease BT in SBS in rats with parenteral nutrition (PN). METHODS: Thirty-eight adult Wistar rats underwent central venous cannulation and were assigned randomly to 1 of 4 groups receiving for 10 days 4 treatment regimes: (1) 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; (2) GH group (n = 9): fasting, same PN regime and resection, GH (1 mg/kg/d, subcutaneously); (3) EGF group (n = 9): fasting, PN, resection, EGF (150 microg/24 h intravenously); (4) INS group (n = 9): fasting, PN, resection, INS (1 UI/100 g/24 h subcutaneously). At the end of the experiment they were killed, and mesenteric lymph nodes (MLN) and peripheral and portal blood samples were recovered and cultured. Several fragments of intestine were taken to determine cell proliferation (PCNA index) and morphometric parameters (villous height, crypt depth). RESULTS: GH, EGF, and INS groups showed a 28%, 29%, and 30% increase in gut mucosal thickness, and PCNA index rose 21%, 20%, and 25%, respectively in comparison with PN controls. Bacterial translocation to peripheral blood was detected in 0% of PN animals and in 44%, 40%, and 28% of GH, EGF, or INS rats, respectively (P < .05). No differences were found in BT in MLN or portal blood among groups. CONCLUSION: Administration of GH, EGF, or INS improves gut mucosal structure in rats with SBS under PN, but, surprisingly, the incidence of BT detected in peripheral blood was increased rather than decreased in animals receiving these treatments.

Bacterial translocation and T-lymphocyte populations in experimental short-bowel syndrome.

Bacterial translocation (BT) accounts in part for sepsis in short-bowel syndrome in which total parenteral nutrition (TPN) is routinely necessary. TPN "per se" facilitates BT and it has been suggested that decreased T-lymphocyte populations (TLP) in newborn rabbits and nude mice promote BT as well. We have tested the hypothesis that BT and modifications in TLP are to be expected in rats subjected to TPN and gut resection. Forty-five adult Wistar rats underwent central venous cannulations and were randomly assigned to one of three groups receiving for ten days three treatment regimes: - Group Sham (n = 17) oral intake of rat chow + saline (300 ml/kg/24 h) through a jugular vein catheter. - Group TPN (n = 17) fasting + infusion of all-in-one TPN solution (300 ml/kg/24 h). - Group RES (n = 11) fasting, same TPN regime + 80% gut resection. At the end of the experiment they were sacrified and specimens (peripheral and portal blood, spleen and mesenteric lymph nodes) were recovered, cultured and/or assessed for CD4+ and CD8+. Bacterial translocation was found in 47% of TPN animals, 92% of RES rats, but not in SHAM ones. Lymphocyte populations were not different in BT+ (n = 8) or BT- (n = 9) rats in the TPN group. TPN and resected animals showed a rise in CD4+ and a drop in CD8+ (then a better CD4+/CD8 ratio) when comparing with SHAM group rats. From this data we may conclude that: 1) BT is frequent if TPN is administered, and constant in resected animals. 2) No apparent relationship between the proportions of CD4+ and CD8+ lymphocytes and BT could be shown in TPN group. 3) High CD4+/CD8+ ratio in TPN and RES groups demonstrate that BT is possible even having good TLP.

Bacterial translocation is favored by the preservation of the ileocecal valve in experimental short bowel with total parenteral nutrition.

Sepsis in short-bowel syndrome (SBS) is in part due to bacterial translocation (BT). Parenteral nutrition (PN) is often necessary in SBS and promotes BT. The aim of this study was to asses the effect of the presence or absence of ileocecal valve (ICV) on BT in parenterally-fed rats with massive intestinal resection. Sixty-five adult Wistar rats underwent central venous cannulations and were randomly assigned to one of five groups receiving for ten days five treatment regimes: Sham (n = 17) standard rat chow + i.v. saline. PN (n = 17) fasting + PN. Res-Sham (n = 10) standard rat chow + i.v. saline + 80% gut resection. Res-PN (n = 11) fasting, PN + 80% gut resection. Res-ICV-PN (n = 10) fasting, PN + 80% gut resection including ICV. At the end of the experiment they were euthanized and mesenteric lymph nodes (MLN), spleen and peripheral and portal blood specimens were recovered and cultured. BT was found in 47% of PN animals, 91% of Res-PN rats, 100% of Res-Sham group and 60% of Res-ICV-PN animals, but not in Sham ones. 97% of BT+ animals had positive cultures in MLN and/or portal blood, whereas germs beyond liver were detected in 30% of Res-Sham, 37% of PN, 50% of Res-PN and 0% of Res-ICV-PN rats. The present study confirms that both massive intestinal resection and PN promote BT. In addition, it shows that animals deprived of ICV have lower incidence of BT in this setting than those with it and that the germs do not reach in them peripheral blood in the same proportions as in ICV-intact animals. These results suggest that the presence of an intact ICV favor BT in parenterally-fed rats with massive intestinal resection.

[Pulmonary infection caused by Rhodococcus equi in a renal transplant recipient]. / Infección pulmonar por Rhodococcus equi en un trasplantado renal.

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.

[The indications for the antipneumococcal vaccine in Spain]. / Indicación de la vacuna antineumocócica en España.

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 translocation associated with short bowel: role of ileocecal valve and cecum]. / La traslocación bacteriana asociada al intestino corto: papel de la válvula ileocecal y del ciego.

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.

[Incidence of bacterial translocation in four different models of experimental short bowel syndrome]. / Incidencia de la traslocación bacteriana en cuatro modelos diferentes de intestino corto experimental.

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.

[Beneficial effects of Bifidobacterium lactis in the prevention of bacterial translocation in experimental short bowel syndrome]. / Utilidad del Bifidobacterium lactis en la prevención de la translocación bacteriana en el intestino corto experimental.

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.

[Tissue antioxidant capacity and bacterial translocation in parenteral nutrition. Experimental study]. / Capacidad antioxidante tisular y traslocación bacteriana bajo nutrición parenteral. Estudio experimental.

Alterations in the antioxidant system (AS) has been observed during total parenteral nutrition (TPN). Light exposure or changes in the composition of TPN may affect this deleterious effect. On the other hand, bacterial translocation (BT) is frequent under TPN and may be related to AS. The aim of the study was to determine the adverse effect of standard and glutamine-enriched (GE) TPN, with or without light exposure, on the AS, and its relationship to BT. Forty-nine adult Wistar rats underwent central venous cannulation and were randomly assigned to one of five groups: Sham (n = 16): chow and water ad libitum and saline i.v. TPN (n = 10): had standard TPN. TPN(-) (n = 8): standard TPN without light-exposure. GTPN (n = 8): GE TPN. GTPN(-) (n = 7): GE TPN without light exposure. After 10 days, glutation reduced (GSH) was determined in liver and kidney. Mesenteric lymph nodes, peripheral and portal blood samples were cultured for BT. Comparing to Sham rats, TPN groups had statistically significant lower GSH levels, but there were no differences between standard or GE groups nor with or without light exposure groups. Sham animals had 12% BT. Significantly higher BT (p < 0.05) was found in TPN rats: 70% in TPN group, 88% in TPN(-) group, 86% in GTPN(-) animals and only 50% in GTPN group (p = 0.06 vs TPN group). To conclude: 1. TPN reduces antioxidant capacity and induces BT. 2. Glutamine supplementation or light protection do not improve tissue antioxidant capacity under TPN. 3. Glutamine supplementation tends to reduce BT only in the presence of light. 4. Absence of light exposure does not improve BT TPN-related.

[Effect of various trophic factors on bacterial translocation in experimental short bowel syndrome]. / Efecto de diferentes factores tróficos sobre la traslocación bacteriana en el síndrome de intestino corto experimental.

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.

Streptococcus pneumoniae ocular infections, prominent role of unencapsulated isolates in conjunctivitis.

The aim of this study was to determine the characteristics and shifts in serotype distribution of pneumococcal isolates causing ocular infections in a region of northern Spain in two periods: 1999-2010 for episodes of conjunctivitis (n = 612) and 1980-2010 for uncommon and more severe non-conjunctival ocular infections (n = 36). All isolates were serotyped and non-typeable isolates were confirmed as unencapsulated by multiplex-PCR of the lytA, ply and cpsA genes. Genotyping was done by pulsed-field gel electrophoresis and multi-locus sequence typing. Most conjunctivitis cases occurred in children under 5 years old (89.5%), and more severe non-conjunctival ocular infections occurred in patients older than 25 years (86.1%). Unencapsulated isolates were detected in 213 conjunctivitis episodes (34.8%) and one non-conjunctival infection (2.8%). Rates of unencapsulated isolates were similar throughout the study. Among 399 conjunctival encapsulated isolates, the most prevalent were serotypes 19A (n = 53), 15B (n = 30), 6A (n = 27), 19F (n = 25), 23F (n = 21) and 6B (n = 17). The most prevalent serotypes in non-conjunctival infections were serotype 3 (n = 4), 23F (n = 4), 6B (n = 3) and 19A (n = 3). Conjunctivitis caused by serotypes included in the hepta-valent pneumococcal conjugate vaccine steadily decreased, accounting for 34.9% (22/63) in 1999-2001, 19.7% (23/117) in 2002-04, 13.6% (33/242) in 2005-07 and 3.2% (6/190) in 2008-10. Among the 213 unencapsulated isolates, 31 different pulsed-field gel electrophoresis patterns were identified. The main clonal complexes (CC) were CC941 (ST941, ST942), CC448 (ST448) and CC344 (ST344, ST3097). CC941 was the predominant CC in 1999-2001, 2002-04 and 2005-07, being replaced by CC448 in 2008-10. The multidrug-resistant CC344 was present throughout the study.

[Peritoneal pneumococcal infections]. / Infecciones neumocócicas peritoneales.

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.