Localized colonic stem cell transplantation enhances tissue regeneration in murine colitis

Many patients suffer from chronic gastrointestinal diseases characterized by chronic inflammation, increased intestinal permeability and visceral pain in which there is no definitive treatment. Adult stem cells have recently been used in various disease states to contribute wound-healing processes. In the current study we investigated the ability of intra-colonic adult stem cells application to heal colonic inflammation in IL-10(-/-) mice with active colitis. The aims of this study were to determine whether intra-colonic infusion of adult colonic stem cells (CSCs) (local stem cell transplantation): (i) restores intestinal permeability; (ii) attenuates visceral hypersensitivity; (iii) heals murine colitis. IL-10(-/-) mice with active colitis were transplanted with adult stem cells. Mice received either a single intracolonic infusion of CSCs or colonic epithelial cells. Two weeks after transplantation, we measured visceral hypersensitivity and intestinal permeability and correlated these with histological improvement of colitis. IL-10(-/-) mice that received stem cell transplantation showed histopathologic evidence of recovery from colitis. Improvement in colitis as graded by pathology scores correlated with restoration of intestinal permeability and decreased visceral hypersensitivity. Intra-colonic administration of CSCs is a potential therapeutic method for treating refractory symptoms in patients with chronic gastrointestinal diseases associated with chronic inflammation and visceral hypersensitivity. This method may be safer and should have far fewer side effects than systemic stem cell administration.     

Effects of antioxidant therapy on leukocyte myeloperoxidase and Cu/Zn-superoxide dismutase and plasma malondialdehyde levels in experimental colitis

The aim of the present study was to evaluate the effects of N-acetylcysteine (NAC) and L-carnitine (LCAR) supplementations on polymorphonuclear leukocytes myeloperoxidase (MPO) and Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and plasma malondialdehyde (MDA) in acetic acid (AA)-induced ulcerative colitis model. The mean polymorphonuclear leukocyte MPO and Cu/Zn-SOD activity was significantly higher in the colitis group than in the control group. Both NAC and LCAR pretreatment markedly decreased MPO and Cu/Zn-SOD activity compared to colitis group. AA administration significantly increased the levels of plasma MDA in comparison with controls. However, NAC and LCAR administration to the AA-treated rats significantly reduced the MDA levels compared to colitis group. In conclusion NAC and LCAR could be beneficial agents in restoring the circulating proinflammatory mediators.     

Antibiotic treatment with ampicillin accelerates the healing of colonic damage impaired by aspirin and coxib in the experimental colitis. Importance of intestinal bacteria, colonic microcirculation and proinflammatory cytokines

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for their anti-inflammatory, analgesic and antipyretic effects, however their use is associated with the broad spectrum of side effects observed in human as well as the experimental animals. Despite damaging activity of NSAIDs in upper gastrointestinal (GI) tract, these drugs exert deleterious influence in lower GI tract, including colon. The role of GI microflora in the pathogenesis of NSAIDs-induced experimental colonic damage is not completely understood. The aim of this study was 1) to evaluate the relative importance of the GI microflora on the experimental colonic damage in the presence of caused by NSAID, and 2) to assess the efficacy of antibiotic treatment with ampicillin on the process of healing of colitis. We compared the effect of vehicle, ASA applied 40 mg/kg intragastrically (i.g.) or the selective cyclooxygenase (COX)-2 inhibitor, celecoxib (25 mg/kg i.g.) without or with ampicillin treatment (800 mg/kg i.g.) administered throughout the period of 10 days, on the intensity of TNBS-induced colitis in rats. The severity of colonic damage, the alterations in the colonic blood flow (CBF) and myeloperoxidase (MPO) activity, the mucosal expression of TNF-α, IL-1β, COX-2, VEGF and iNOS and the plasma concentration of TNF-α and IL-1β were assessed. In all rats, the faeces samples as well as those from the colonic mucosa, blood, liver and spleen underwent microbiological evaluation for intestinal bacterial species including Escherichia coli and Enterococcus spp. The administration of TNBS resulted in macroscopic and microscopic lesions accompanied by the significant fall in the CBF, an increase in tissue weight and 4-5-fold rise in the MPO activity and a significant increase in the plasma IL-1β and TNF-α levels. ASA or celecoxib significantly increased the area of colonic lesions, enhanced MPO activity and caused the marked increase in colonic tissue weight and plasma IL-1β and TNF-α levels, as well as an overexpression of mRNA for IL-1β and TNF-α, COX-2, VEGF and iNOS in the colonic tissue. ASA and coxib also resulted also in a significant increase of E. coli counts in the stool at day 3 and day 10 day of the observation compared with the intact rats. Moreover, E. coli translocation from the colon to the blood and extraintestinal organs such as liver and spleen in the group of rats treated without or with ASA and coxib. E. coli was the most common bacteria isolated from these organs. Treatment with ampicillin significantly attenuated the ASA- or celecoxib-induced increase in plasma levels of IL-1β and TNF-α and suppressed the mucosal mRNA expression for IL-1β and TNF-β, COX-2, iNOS and VEGF in the colonic mucosa. Ampicillin administration caused a significant fall in the number of E. coli in the faeces at day 3 and day 10 of observation in ASA- and coxib-treated rats with colitis. Antibiotic therapy markedly reduced bacterial translocation to the colonic tissue and the extraintestinal organs such as the liver and spleen. We conclude that administration of ASA and to lesser extent of celecoxib, delays the healing of experimental colitis and enhances the alterations in colonic blood flow, proinflammatory markers such as IL-1β, TNF-α, COX-2, iNOS and VEGF and increased intestinal mucosal permeability resulting in the intestinal bacterial translocation to the blood, spleen and liver. Antibiotic treatment with ampicillin is effective in the diminishing of the severity of colonic damage, counteracts both the NSAID-induced fall in colonic microcirculation and bacterial E.coli translocation to the extraintestinal organs.     

Oral administration of recombinant cholera toxin subunit B inhibits IL-12-mediated murine experimental (trinitrobenzene sulfonic acid) colitis

Trinitrobenzene sulfonic acid (TNBS)-induced colitis is an IL-12-driven, Th1 T cell-mediated colitis that resembles human Crohn's disease. In the present study, we showed initially that the oral administration of recombinant subunit B of cholera toxin (rCT-B) at the time of TNBS-induced colitis by intrarectal TNBS instillation inhibits the development of colitis or, at later time when TNBS-induced colitis is well established, brings about resolution of the colitis. Dose-response studies showed that a majority of mice (68%) treated with rCT-B at a dose of 100 microg (times four daily doses) exhibited complete inhibition of the development of colitis, whereas a minority (30%) treated with rCT-B at a dose of 10 microg (times four daily doses) exhibited complete inhibition; in both cases, however, the remaining mice exhibited some reduction in the severity of inflammation. In further studies, we showed that rCT-B administration is accompanied by prevention/reversal of increased IFN-gamma secretion (the hallmark of a Th1 response) without at the same time causing an increase in IL-4 secretion. This decreased IFN-gamma secretion was not associated with the up-regulation of the secretion of counterregulatory cytokines (IL-10 or TGF-beta), but was associated with a marked inhibition of IL-12 secretion, i.e., the secretion of the cytokine driving the Th1 response. Finally, we showed that rCT-B administration results in increased apoptosis of lamina propria cells, an effect previously shown to be indicative of IL-12 deprivation. From these studies, rCT-B emerges as a powerful inhibitor of Th1 T cell-driven inflammation that can conceivably be applied to the treatment of Crohn's disease.     

Comparative Double-blind Trial of Cephalexin and Ampicillin in Treatment of Urinary Infections

Cephalexin was compared with ampicillin in the treatment of urinary tract infections by a random double-blind technique. Both drugs were found to be equally effective. In 21 out of 31 patients treated with cephalexin and in 20 out of 31 treated with ampicillin the urine was sterile three weeks after starting therapy. The bacteriological findings at one and eight weeks were also similar in both groups. No serious adverse reactions were attributable to cephalexin, which seemed to be tolerated rather better than ampicillin.     

Relative bioavailability of commercial ampicillin formulations in man

The relative bioavailability of three commercial ampicillin products was examined in 12 human subjects using a crossover experimental design. Based upon the areas under the ampicillin plasma concentration-time curves after the oral administration of 250 mg. ampicillin and using an analysis of variance technique no statistically significant differences were found between the products examined. These findings are in contrast to those of a recent report and appear to be explained by formulation differences. These relatively minor differences in formulation reflect the importance of formulation variables in providing efficient drug therapy. The intrasubject variation associated with several of these products is quite marked and is consistent with the incomplete and erratic absorption of this antibiotic in man.     

Probiotics ameliorate recurrent Th1-mediated murine colitis by inducing IL-10 and IL-10-dependent TGF-beta-bearing regulatory cells

Recent studies of murine models of mucosal inflammation suggest that, whereas some kinds of bacterial microflora are inducers of disease, others, known as probiotics, prevent disease. In the present study, we analyzed the regulatory cytokine and cell response to probiotic (VSL#3) administration in the context of the Th1 T cell colitis induced by trinitrobenzene sulfonic acid treatment of SJL/J mice. Daily administration of probiotics for 3 wk to mice during a remission period between a first and second course of colitis induced by trinitrobenzene sulfonic acid, resulted in a milder form of recurrent colitis than observed in mice administered PBS during this same period. This protective effect was attributable to effects on the lamina propria mononuclear cell (LPMC) population, because it could be transferred by LPMC from probiotic-treated mice to naive mice. Probiotic administration was associated with an early increase in the production of IL-10 and an increased number of regulatory CD4+ T cells bearing surface TGF-beta in the form of latency-associated protein (LAP) (LAP+ T cells). The latter were dependent on the IL-10 production because administration of anti-IL-10R mAb blocked their appearance. Finally, the LAP+ T cells were essential to the protective effect of probiotics because administration of anti-IL-10R or anti-TGF-beta at the initiation of recurrent colitis induction or depletion of LAP+ T cells from LPMC abolished the latter's capacity to transfer protection to naive recipients. These studies show that probiotic (VSL#3) administration during a remission period ameliorates the severity of recurrent colitis by inducing an immunoregulatory response involving TGF-beta-bearing regulatory cells.     

Autotaxin (ATX) inhibits autophagy leading to exaggerated disruption of intestinal epithelial barrier in colitis

Inflammatory bowel disease (IBD) is an immune-mediated disease. Autotaxin (ATX) is associated with increased inflammatory molecules, however, its effect on IBD is not well understood. Autophagy plays an important role in IBD, whether ATX and autophagy act in concert in IBD remains unknown. This study is to explore the possible mechanisms of ATX affecting autophagy leading to the disruption of intestinal epithelial barrier, thereby exacerbating colitis. The expression of ATX was upregulated in UC patients and dextran sulfate sodium (DSS)-induced colitis mice. Here, we described that providing an ATX inhibitor during DSS colitis increased autophagy and ameliorated colonic inflammation. Conversely, intrarectal administration with recombinant (r)ATX increased colitis and decreased autophagy. This pro-colitic effect was attenuated in mice treated with rapamycin, resulting in increased autophagy activity and mild colitis. Moreover, the inhibitory effect of rATX on autophagy was confirmed in vitro and was reversed by the addition of rapamycin. The damaging effects of ATX on epithelial barrier function were reversed by ATX inhibitor or rapamycin treatment. In sum, our results show that ATX can inhibit autophagy through the mTOR pathway, resulting in exaggerated damage to the intestinal epithelial barrier during colitis. These findings suggest that ATX may be a key pro-colitic factor, and represent a potential therapeutic target for treating IBD in the future.     

An evaluation of ampicillin pharmacokinetics and toxicity in guinea pigs

Sodium ampicillin was administered subcutaneously to 350-550 g male Dunkin Hartley guinea pigs at doses of 6, 8 and 10 mg/kg tid for 5 days. Over a period of 12 days, the lowest ampicillin dose appeared to be tolerated well. However, significant body weight reduction and mortality occurred with the two higher dosage regimens. Cecal cultures of dead animals confirmed the presence of Clostridium difficile, an organism associated with antibiotic-induced enterotoxemia. Assay of serum collected from ampicillin-treated animals revealed ampicillin concentrations of approximately 10 micrograms/ml at 5 minutes post-dosing which fell precipitously to less than 0.2 micrograms/ml at 60 minutes. Determination of biliary ampicillin levels during the 60 minutes after administration of a single 10 mg/kg SQ dose revealed concentrations ranging from 18 micrograms/ml to 90 micrograms/ml. Estimates of total urinary ampicillin content after a single 10 mg/kg SQ dose were less than 500 micrograms/animal at 7.5 minutes, but increased to greater than 2000 micrograms/animal at 60 minutes after dosing. Results of this study indicated that due to its short serum half-life, sodium ampicillin probably has little systemic therapeutic efficacy in guinea pigs. Because high concentrations of ampicillin accumulated in the urine and bile, the antibiotic probably would have therapeutic efficacy for urinary and intestinal infections. However, its associated toxicity at large doses probably precludes its use. In view of the rapid clearance of ampicillin in guinea pigs in comparison to other species, the pharmacokinetics of other antibiotics, especially those reported to be less toxic for guinea pigs, should be considered.     

The Effects of Peritoneal Dialysis on the Physiological Disposition of Oxacillin,Ampicillin and Tetracycline in Patients with Renal Disease

Seven patients with acute or chronic renal failure who were receiving intermittent peritoneal dialysis and who required parenteral oxacillin, ampicillin or tetracycline were studied to determine the disposition of these antibiotics in severe renal disease and the effects of peritoneal dialysis. While severe renal impairment markedly prolongs persistence in the serum of ampicillin and tetracycline, there is little effect on oxacillin. Whereas required doses of ampicillin and tetracycline are lower in the presence of severe renal disease, oxacillin should be given in doses equivalent to those used for patients with normal renal function. Peritoneal dialysis does not alter these dosage requirements.Four patients receiving ampicillin or tetracycline in the infusing solution during peritoneal dialysis were studied to determine the amount of systemic absorption. Local prophylaxis alone is not achieved with this method of administration, since small amounts of both antibiotics are absorbed systemically from the infusing solution. The serum concentration of tetracycline attained is inadequate for treatment of systemic infections but is probably significant, with repeated use in intermittent dialysis, in causing adverse effects. Tetracycline should be abandoned in the local prophylaxis of peritonitis during peritoneal dialysis.     

Effect of sulphasalazine on the human intestinal flora

Sulphasalazine is commonly used to treat patients with ulcerative colitis but the mode of action is still unexplained. To investigate a possible antibacterial effect of sulphasalazine, the faecal flora composition was studied in patients with ulcerative colitis and in mice harbouring a human intestinal flora. Patients on sulphasalazine were found to have an intestinal flora that was completely resistant to sulphapyri-dine. Oral administration of sulphasalazine did not influence the composition of the human flora in mice.     

难辨梭菌性肠炎与肠菌群失调的关系

本文对11例难辨梭菌性肠炎(CDEC)患者的粪便进行10种肠道菌的定量分析,并与20例其他原因腹泻病人和22例健康成人的肠菌比较。结果表明CDEC病人的粪中大肠杆菌和双歧杆菌明显低于两对照组,其他菌类与对照组无明显差别,提示大肠杆菌和双歧杆菌的减少在CDEC发病中起重要作用。此外,我们对CDEC病人发病前所用抗生素作了统计分析,结果发现:使用较多的有庆大霉素、氨苄青霉素和先锋霉素     

Crucial Role for CD69 in the Pathogenesis of Dextran Sulphate Sodium-Induced Colitis

CD69 is a membrane molecule transiently expressed on activated lymphocytes, and its selective expression in inflammatory infiltrates suggests that it plays a role in the pathogenesis of inflammatory diseases. In this study, we used CD69-deficient (CD69 KO) mice to assess the role of CD69 in the pathogenesis of dextran sulphate sodium (DSS)-induced acute and chronic colitis. The severity of colitis was assessed by the survival rate, clinical signs, colon length, histological examination and the expression of cytokines and chemokines in the large intestines. Both acute and chronic colitis were attenuated in the CD69 KO mice, as reflected by the lower lethality, weight loss, clinical signs, and improved histological findings. CD69⁺ cells infiltrated extensively into the inflamed mucosa of the colon in WT mice after DSS treatment. Experiments with the transfer of WT CD4 T cells into CD69 KO mice restored the induction of colitis. The administration of an anti-CD69 antibody also inhibited the induction of the DSS-induced colitis. These results indicate that CD69 expressed on CD4 T cells plays an important role in the pathogenesis of DSS-induced acute and chronic colitis, and that CD69 could be a possible therapeutic target for colitis.     

Increase in efficacy of antibiotic therapy of anthrax under experimental conditions]

The results of experimental therapy of antraxis infected mice with cefazoline (kefzol) and ampicillin incapsulated into liposomes are presented. Protective activity of the same free antibiotics combinated with amixine and leukinferone was evaluated also. Treatment with liposomal cefazoline enhanced mice survival upto 60 per cent, and life period upto 1.3 +/- 0.3 days. After liposomal ampicillin administration for 3 times the same indices were 60 per cent and 6.5 +/- 0.9 days, after 2 times administration--80 per cent and 14 +/- 1.8 days when compared to the groups of the animals treated with free antibiotics. It was shown that administration of ampicillin with amixine or with leukinferone provided enhanced mice survival upto 20 per cent, administration of cefazoline with leukinferone--upto 30 per cent.     

Diminished nitroprusside-induced relaxation of inflamed colonic smooth muscle in mice.

The dextran sodium sulphate (DSS) induced colitis in mice was used as a experimental model to study the contractility of murine longitudinal colonic smooth muscle during inflammation. Smooth muscle segments of proximal, middle and distal colon were mounted in organ baths. Smooth muscle contraction was induced by carbachol showing an aboral increase in activity, whereas in the inflamed middle colonic segment a marked decrease in activity was observed. The dilatative effect of sodium-nitroprusside (SNP) as a nitric oxide donor was investigated after precontraction by carbachol. Both in normal and DSS segments administration of SNP to isolated mouse colonic smooth muscle preparations caused regional differences in relaxation, the highest relaxation seen in normal proximal colonic tissue. However, this relaxation was markedly reduced in inflamed proximal preparations, associated with a diminished cGMP contents.     

Short-chain fatty acids administration is protective in colitis-associated colorectal cancer development

Reduced short-chain fatty acids (SCFAs) have been reported in patients with ulcerative colitis, and increased intake of dietary fiber has shown to be clinically beneficial for colitis. Whether SCFAs suppress tumorigenesis in colitis-associated colorectal cancer remains unknown. The chemopreventive effect of SCFAs in colitis-associated colorectal cancer was evaluated in this study. Model of colitis-associated colorectal cancer in male BALB/c mice was induced by azoxymethane (AOM) and dextran sodium sulfate (DSS). SCFAs mix (67.5 mM acetate, 40 mM butyrate, 25.9 mM propionate) was administered in drink water during the study period. Macroscopic and histological studies were performed to examine the colorectal inflammation and tumorigenesis in AOM/DSS-induced mice treated with or without SCFA mix. The effects of SCFAs mix on colonic epithelial cellular proliferation were also assessed using Ki67 immunohistochemistry and TUNEL staining. The administration of SCFAs mix significantly reduced the tumor incidence and size in mice with AOM/DSS-induced colitis associated colorectal cancer. SCFAs mix protected from AOM/DSS-induced colorectal cancer by improving colon inflammation and disease activity index score as well as suppressing the expression of proinflammatory cytokines including IL-6, TNF-α and IL-17. A decrease in cell proliferation markers and an increase in TUNEL-positive tumor epithelial cells were also demonstrated in AOM/DSS mice treated with SCFAs mix. SCFAs mix administration prevented development of tumor and attenuated the colonic inflammation in a mouse model of colitis-associated colorectal cancer. SCFAs mix may be a potential agent in the prevention and treatment of colitis-associated colorectal cancer.     

Assessment of the efficacy of treating infections in hematopoietic proliferative diseases: Monotherapy with ceftazidime and tobramycin combined with amoxycillin/ampicillin

Efficacy of the ceftazidime monotherapy in 120 febrile children with neoplastic diseases and granulocytopenia was compared with that of tobramycin combined with amoxycillin/ampicillin. The obtained results were similar in both types of antibiotic therapy. However, granulocytopenia was higher and septicemia was more frequent in children treated with ceftazidime. Isolated bacteria were more sensitive to ceftazidime than to tobramycin with amoxycillin/ampicillin. Both regimens were tolerated well. Despite a low number of patients in both groups, one may conclude that ceftazidime is more efficient in patients with granulocytopenia. Less adverse reactions, lower number of infections, less frequent medical procedures, elimination of the potentially toxic aminoglycosides and lower cost of therapy advocate the use of ceftazidime monotherapy.     

X-ray colonometry in the diagnosis of colonic dyskinesias and inflammatory diseases

Clinical and X-ray studies were made in 316 patients, which revealed intestinal dyskinesia, chronic colitis, and nonspecific ulcerative colitis in 105, 133, and 78 patients, respectively. Irrigoscopy (administration of a contrast enema, examination of the mucosal contour, and double contrasting) was performed in all the patients, by analyzing X-ray planimetric indices. X-ray colonoplanimetry makes it possible to objectify the interpretation of the X-ray pattern in chronic inflammatory diseases of the large bowel and colonic dyskinesia.     

Prospective Study of Ampicillin Rash

A multicentre prospective study of 933 patients being treated with ampicillin showed a rash incidence of 7·3%. The rash was commonest in women and patients suffering from viral infections. Most rashes were maculopapular and were not associated with features of true penicillin allergy. We conclude that the development of a maculopapular rash during or after treatment with ampicillin is not in itself a contraindication to future treatment with the penicillins.