bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rifaximin: A Nonabsorbed Antimicrobial in the Therapy of Travelers’ Diarrhea
Authors: DuPont H.L. , Ericsson C.D. , Mathewson J.J. , Palazzini E. , DuPont M.W. , Jiang Z.D. , Mosavi A. , de la Cabada F.J. 
Published: April 2003

<b>Background/Aims:</b> Bacterial enteropathogens, the major cause of travelers’ diarrhea, are customarily treated with antibacterial drugs. Rifaximin, a nonabsorbed antimicrobial was examined as treatment for travelers’ diarrhea. <b>Methods:</b> A randomized, prospective, double-blind clinical trial was carried out in 72 US adults in Mexico. Patients with acute diarrhea received one of three doses of rifaximin (200, 400 and 600 mg t.i.d.) or trimethoprim/sulfamethoxazole (TMP/SMX, 160 mg/800 mg b.i.d.) for 5 days. Results were compared with data from 2 placebo-treated historical control populations. <b>Results:</b> The shortest duration of treated diarrhea was seen in the group receiving 200 mg rifaximin t.i.d (NS). Clinical failure to respond to treatment occurred in 6 of 55 (11%) rifaximin-treated subjects versus 5 of 17 (29%) of TMP/SMX-treated subjects (NS). Sixteen of twenty (80%) of the enteropathogens isolated from the rifaximin-treated subjects and 7 of 7 (100%) from the TMP/SMX group were eradicated by treatment (NS). Sixteen of twenty-four (67%) enteropathogens identified were susceptible to TMP and all 24 were inhibited by ≤50 µg/ml of rifaximin. Rifaximin reduced the number of unformed stools passed during the first 24 h of treatment when compared with 2 control placebo groups (3.3 versus 5.1; p = 0.008 and 0.0001) and led to a reduced duration of post-enrollment diarrhea (mean values of 43.1 versus 68.1 and 81.9 h; p = 0.001). <b>Conclusions:</b> Rifaximin shortened the duration of travelers’ diarrhea compared with TMP/SMX and 2 earlier studied placebo-treated groups. A poorly absorbed drug if effective in treating bacterial diarrhea has pharmacologic and safety advantages over the existing drugs.
Comparison of Oxidative Phosphorylation in the Anastomosis of the Small and Large Bowel
Authors: Testini M. , Scacco S. , Loiotila L. , Papa F. , Vergari R. , Regina G. , Nicolardi V. , Paccione F. 
Published: April 2003

Dehiscence of anastomosis in the large bowel (LB) is more frequent compared with that in the small bowel (SB). The pathophysiological mechanisms underlying the phenomenon are well known. The goal of this study is to demonstrate the different oxidative phosphorylation roles in the response of the anastomosed SB and LB. In 45 male rabbits under general anaesthesia, the ileum and colon were transected always on the same side and an end-to-end anastomosis was constructed using single-layer inverting interrupted 5-0 Ethilon sutures. Tracts containing bowel anastomoses were collected at 3, 12 and 24 h and 3, 7 and 21 days after the operation and compared with non-anastomosed bowel. Respiratory rates with different substrates, enzymatic activities, respiratory complex structures and cytochrome contents were measured in smooth muscle purified mitochondria. Mitochondrial respiration showed significant differences in the LB versus anastomosed SB: respiratory rates were markedly reduced in the LB (residual activity: 25 vs. 95% of the SB). Detailed analysis of other mitochondrial parameters confirmed a better tolerance of the ileum to anastomosis. From these preliminary studies we can consider two different aerobic thresholds for either the large or the small rabbit intestine, the latter being oxygen dependent. This can explain the mitochondrial sufferance of anastomosis in the LB whose prevalent aerobic metabolism can be more easily affected by different noxae if compared with the tendency to glycolytic metabolism of the small intestine.
Attenuation of Renal Ischemia-Reperfusion Injury in Rats by Allopurinol and Prostaglandin E<sub>1</sub>
Authors: Gupta P.Ch. , Matsushita M. , Oda K. , Nishikimi N. , Sakurai T. , Nimura Y. 
Published: April 2003

50 Sprague-Dawley rats were used to study the effect of allopurinol and prostaglandin E<sub>1</sub> (PGE<sub>1</sub>) on renal ischemia-reperfusion injury. They underwent left renal ischemia for 1 h and reperfusion. A right nephrectomy was performed, and 5 groups were made. Group AP received allopurinol 50 mg/kg and PGE<sub>1</sub> 20 µg/kg; group A, allopurinol; group P, PGE<sub>1</sub>; group C, control, and group S, sham group. Five animals from each group were used to study renal functions and 5 for renal histology. The serum creatinine values were lower in the treatment groups compared to the controls on days 1–3 and 7 (p < 0.05). The blood urea nitrogen values showed a similar trend. Maximum histological damage was seen in group C, followed by groups A, P and AP, in this order. We conclude that allopurinol and PGE<sub>1</sub> attenuate renal ischemia-reperfusion injury in rats.
Effects of Prostaglandin E<sub>1</sub> on Hepatic Blood Flow in Conscious Dogs with Chronic Biliary Obstruction
Authors: Machiki Y. , Nimura Y. , Kanda H. , Uematsu T. , Kitagawa Y. , Kamiya S. , Watanabe T. 
Published: April 2003

To evaluate the effects of prostaglandin E<sub>1</sub> (PGE<sub>1</sub>) on the hepatic circulation in cholestasis, hepatic arterial blood flow (HAF), portal venous blood flow (PVF), cardiac output, and heart rate during PGE<sub>1</sub> infusions were investigated before and 2 weeks after biliary obstruction in conscious dogs by a transit-time ultrasonic flowmeter. In the control period, HAF and PVF increased dose dependently with the infusion of PGE<sub>1</sub> from 0.05 to 0.5 µg/kg/min. During the biliary obstruction period, a lower dose of PGE<sub>1</sub> increased HAF and PVF. The plasma concentration level of PGE<sub>1</sub> during the infusion of PGE<sub>1</sub> was significantly higher at each dose in the cholestatic animals. These results suggest that the metabolism of PGE<sub>1</sub> is attenuated by cholestasis. Plasma PGE<sub>1</sub> concentrations should be useful in deciding the optimal dose of PGE<sub>1</sub>.
Effect of Magnetic Stimulation on the Contractile Activity of the Rectum in the Dog
Authors: Shafik A. 
Published: April 2003

<b>Purpose:</b> Magnetic stimulation (MS) produces its effect, according to Faraday’s law, by creating an electric field which can stimulate the neuromuscular tissues. The current study investigates, to our knowledge for the first time, the effect of MS on rectal pressure and evacuation with a view on its possible application in emptying the inertic or neuropathic rectum. <b>Methods:</b> The rectal, rectal neck and vesical pressures as well as the EMG activity of the two rectus abdominis muscles were recorded during sacral MS with a magnetic coil while the rectum was empty and while filled. Stimulation parameters were set at 70% intensity, 20 Hz freqency and 1- to 5-second burst length. <b>Results:</b> Sacral MS of both the filled and empty rectum effected a significant increase in rectal (p < 0.01) and vesical (p < 0.01) pressures and a decrease in rectal neck pressure (p < 0.01). Rectal evacuation of the filled rectum using intermittent stimulation was achieved in all animals. <b>Conclusion:</b> Sacral MS resulted in a rectal evacuation. It is a simple, easy and noninvasive method that might prove applicable in the treatment of inertic constipation and neuropathic rectum.
FK506 with Portal Decompression Exerts Beneficial Effects following Extended Hepatectomy in Dogs
Authors: Mitsumoto Y. , Dhar D.Kumar , Yu L. , Soda Y. , Kinugasa S. , Kohno H. , Nagasue N. 
Published: April 2003

The present study was designed to elucidate the effectiveness of portal decompression and FK506 (FK) pretreatment in extended hepatectomy in dogs. In the first set of experiment the effect of portal decompression was evaluated in two groups of dogs which underwent extended hepatectomies (80%) with or without (control) a side-to-side portacaval shunt. The presence of the shunt significantly (p < 0.05) improved the 7-day survival of the animals (57.1%) when compared with those of the control group (28.6%) and eventually the portal pressure was significantly lower and mean arterial pressure was significantly higher in the shunt group (p < 0.05). Moreover, the animals with lower portal pressure (≤220 mm of saline) had a significantly improved 7-day survival rate than those with higher portal pressure (p < 0.001). To evaluate the role of FK pretreatment in extended hepatectomy, a more severe model of 90% hepatectomy was used in four different groups: portacaval shunt, shunt and FK pretreatment, FK pretreatment, and hepatectomy only (control). Although the shunt improved the survival rate in the 80% hepatectomy model, neither shunt (8.3%) nor FK pretreatment (0%) independently improved the survival of the animals when the hepatectomy was extended to 90%. FK pretreatment significantly improved the survival (33.3%, p < 0.05) and hepatic functions of the animals only in the presence of a shunt. Also hepatic microcirculation measured with a laser Doppler flowmeter was significantly better in the remnant liver of all treated groups than in the control group (p < 0.01). In conclusion, extended hepatectomy (90%) could be performed in otherwise normal liver after FK pretreatment and a side-to-side portacaval shunt, which improve the regenerative response in a stable hemodynamic animal.
Effects of Selective Nitric Oxide Synthase Inhibition in Hyperdynamic Endotoxemia in Dogs
Authors: Wolfárd A. , Kaszaki J. , Szabó C. , Balogh Z. , Nagy S. , Boros M. 
Published: April 2003

<i>Objectives: </i>Our aims were to investigate the systemic hemodynamic effects of constitutive endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) inhibitors in hyperdynamic endotoxemia. <i>Patients and Methods:</i> Group 1 comprised sham-operated controls, while in group 2, 3 and 4, a hyperdynamic circulatory reaction was elicited by a 2-hour infusion of <i>Escherichia coli</i> endotoxin (ETX) in a dose of 5.3 μg/kg. The animals in group 3 were treated with 12.5 mg/kg nonselective NOS inhibitor N-ω-nitro-<i>L</i>-arginine methyl ester (L-NAME), and those in group 4 with 2 mg/kg of the specific iNOS inhibitor S-methyl-isothiourea (SMT). Mean arterial pressure (MAP), cardiac output (CO) and myocardial contractility (MC) were measured, and total peripheral resistance (TPR) was calculated. The eNOS and iNOS activities were determined in myocardial biopsy samples taken after 8 h of endotoxemia. <i>Results:</i> ETX induced significant decreases in TPR and MAP, a transient myocardial depression, and increased the myocardial eNOS and iNOS activities. L-NAME decreased the activities of both isoenzymes, increased MC but induced a fall in CO. SMT inhibited iNOS by 60%, without influencing the eNOS activity, increased MAP and contractility in the early phase of endotoxemia, and induced only a slight decrease in CO. <i>Conclusions:</i> Nonselective NOS inhibition restores the arterial pressure and exerts a positive inotropic effect, but decreases CO. SMT selectively decreases the iNOS activation without disturbing the vasoregulatory function of the eNOS-derived nitric oxide in hyperdynamic endotoxemia in the dog.
Hepatorenal Interaction in Glutathione Redox State during Partial Hepatic Ischemia-Reperfusion in Rats
Authors: Saito S. , Honda K. , Kobayashi N. 
Published: April 2003

The hepatic glutathione metabolism during partial hepatic ischemia-reperfusion was studied in a rat model with special reference to the hepatorenal glutathione metabolism system. Bile samples, and in- and outflow blood and tissue samples of the rat liver, kidney and small intestine were collected during 60 min of 70% partial liver ischemia and reperfusion. Both reduced and oxidized glutathione levels were determined by HPLC. The tissue ratio of reduced to oxidized glutathione (GSH/GSSG ratio) decreased significantly in the ischemic hepatic lobe at 60 min after reperfusion. The GSH/GSSG ratio in bile from the ischemic hepatic lobes decreased significantly after 60 min of ischemia and gradually recovered after reperfusion. The net release of GSH from the nonischemic hepatic lobe increased at 60 min after reperfusion, since the calculated net release of GSH from the whole liver increased significantly whereas there was no change in the net release from the ischemic hepatic lobe. The tissue GSH level in the kidney increased significantly at 180 min after reperfusion. The calculated net uptake of GSH into the kidney, and the net release of total cysteine from the kidney, tended to decrease at the end of 60 min of ischemia, to increase at 60 min after reperfusion and then decrease at 180 min after reperfusion. We found that the hepatorenal glutathione metabolism was changed by partial hepatic ischemia-reperfusion. These changes might reflect a hepatorenal interaction to maintain the glutathione redox state of the vital organs.
Contribution of Proliferating Leukocytes to Phenotypic Change in Smooth Muscle Cells during the Development of Coronary Arteriosclerosis in Transplanted Hearts
Authors: Shirasawa B. , Hamano K. , Ueda M. , Ito H. , Kobayashi T. , Fujimura Y. , Kojima A. , Esato K. 
Published: April 2003

<i>Background:</i> It is well known that coronary arteriosclerosis after heart transplantation is concentric and rich in smooth muscle cells (SMCs); however, the role played by rejection in the intimal thickening caused by SMCs in coronary arteriosclerosis remains unclear. In this study, we examined the process of intimal hyperplasia caused by SMCs and evaluated the relationship between the differentiation state of SMCs and local inflammation caused by rejection. <i>Methods:</i> Lewis rat hearts were heterotopically transplanted into F344 rats (allotransplantation group) or other Lewis rats (isotransplantation group). Cyclosporin A (5 mg/kg/day) was injected intramuscularly for 20 days after transplantation in both groups. The transplanted hearts were examined immunohistochemically using several monoclonal antibodies; namely, HHF-35, CGA7, vimentin, α-actin, HIS36, R73 and proliferating cell nuclear antigen (PCNA). To evaluate the degree of local immunological response caused by rejection, the anti-PCNA antibody was used. To reveal the subtypes of proliferating cells in the thickened intima, HIS36 and R73 antibodies were used. <i>Results:</i> In the allotransplantation group, SMCs in the media began to undergo a phenotypic change toward a poorly differentiated state 30 days after transplantation. Intimal hyperplasia was observed 60 days after transplantation, the thickened intima being composed mainly of dedifferentiated SMCs with abundant PCNA<sup>+</sup>, most of which were macrophages and T cells. The state of differentiation of SMCs in the thickened intima 90 days after transplantation varied from a dedifferentiated to a highly differentiated state. These changes were strongly correlated with the expression of PCNA. <i>Conclusion:</i> The expression of PCNA was strongly correlated with the differentiation state of SMCs. Thus, local inflammation caused by rejection may play an important role in the initiation of phenotypic change in SMCs.
Effect of Fluid Resuscitation with and without Endothelin A Receptor Blockade on Hemoconcentration and Organ Function in Experimental Pancreatitis
Authors: Forgács B. , Eibl G. , Faulhaber J. , Kahrau S. , Buhr H. , Foitzik T. 
Published: April 2003

<i>Background:</i> Intravascular fluid loss contributes to pancreatitis-associated multiple organ dysfunction and is thus a major target for therapy in this life-threatening disease. <i>Aim:</i> To evaluate intravascular fluid loss and extravascular fluid sequestration together with cardiorespiratory and renal function in a well-established rat model of severe acute pancreatitis (AP) and to investigate the effect of fluid resuscitation with and without endothelin receptor A blockade on these parameters. <i>Method:</i> Induction of AP in rats by a standardized bile salt infusion into the pancreatic duct and intravenous cerulein hyperstimulation. Six hours after AP induction, animals were randomized into 4 groups to receive (1) no therapy; (2) 4 ml/kg/h Ringer’s lactate (RL) i.v.; (3) 8 ml/kg/h RL i.v., or (4) 4 ml/kg/h RL plus an endothelin receptor antagonist. Target parameters measured before and after AP induction and during the 24-hour observation period included: mean arterial blood pressure, heart rate, hematocrit, arterial blood gases, urine production, ascites and pleural effusions. <i>Results:</i> After 6 h, all animals presented with severe hemoconcentration (hematocrit >57%) and oliguria (<0.5 ml/6 h). Cardiorespiratory parameters were within the normal range. Up to 12 h after AP induction, animals without therapy had an increased hematocrit and oliguria and developed metabolic acidosis. Animals receiving fluid resuscitation had a significant drop in hematocrit and maintained compensated blood gas values. A significant increase in urine production was only observed in animals given 8 mg/kg/h RL. Between 12 and 24 h, urine production significantly increased with fluid resuscitation and respiratory parameters stabilized except for animals treated with 8 ml/kg/h RL which developed arterial hypoxia and hypercapnia. <i>Conclusions:</i> Intravascular fluid loss and extravascular fluid sequestration together with decreased urine production characterize the early phase of this model of severe AP. Massive fluid resuscitation necessary for increasing urine output may lead to respiratory distress. Reduction of intravascular fluid loss by endothelin receptor blockade is associated with improved renal and respiratory function.
Permanent Access to the Portal Vein in Rats: An Experimental Model
Authors: Gervaz P. , Scholl Beatrix , Gillet M. 
Published: April 2003

A safe and reproducible method for placement of indwelling catheters into the portal venous system is a prerequisite for improved delivery of anticancer drugs to experimental liver metastases. Due to the lack of tumor models in large animals and the difficulty in establishing permanent access to the portal vein in rodents, this type of model has rarely been described in the laboratory setting. We propose a simple, minimally invasive method for repeated portal vein injections in rats. A vascular access device was used, which remained patent for periods of up to 3 months. Placement and support of the catheter tip in the portal vein was performed with a technique designed to avoid portal thrombosis and infections. Permanent portal vein access in a rodent model of liver metastases will be invaluable for the development of novel therapeutic strategies.
Influence of Positive End-Expiratory Pressure Ventilation on Peripheral Tissue Perfusion Evaluated by Measurements of Tissue Gases and pH
Authors: Jedlińska Barbara , Mellström Å. , Jönsson K. , Hartmann M. 
Published: April 2003

Measurements of subcutaneous oxygen tension (PscO<sub>2</sub>), subcutaneous carbon dioxide tension (PscCO<sub>2</sub>) and subcutaneous pH (pHsc) were used for evaluation of peripheral oxygenation in pigs subjected to oleic acid-induced lung injury during ventilation with increasing levels of positive end-expiratory pressure (PEEP). Lung injury resulted in a decrease of arterial oxygen tension (PaO<sub>2</sub>) from 93 to 37 mm Hg (p < 0.01) with maintained cardiac output. PscO<sub>2</sub> decreased from 45 to 17 mm Hg (p < 0.01) and pHsc from 7.47 to 7.39 (p < 0.05), and PscCO<sub>2</sub> increased from 46 to 59 mm Hg (p < 0.05). Increase of PEEP level between 5 and 20 cm H<sub>2</sub>O resulted in a continuous increase of PaO<sub>2</sub> from 45 to 145 mm Hg and a decrease of cardiac output from 4.1 to 2.0 liters/min (p < 0.01). PscO<sub>2</sub> increased up to a PEEP level of 15 cm H<sub>2</sub>O, reaching 26 mm Hg. Further increase of PEEP level up to 20 cm H<sub>2</sub>O resulted in an increase of PscCO<sub>2</sub> from 65 to 71 mm Hg (p < 0.05) and a decrease of pHsc from 7.31 to 7.29 (p < 0.05). In conclusion: measurements of tissue gases and pH can be used to evaluate optimum peripheral tissue oxygenation during titration of PEEP level. Whether these measurements can be used as the only indicator to guide therapy in an individual case remains to be studied.
Prolongation of Cardiac Allograft Survival by Selective Injection of Donor Liver Leukocytes in Non-Immunosuppressed Rats
Authors: Sfeir R. , Gambiez L. , Labalette Myriam , Brami F. , Lecomte Martine , Dessaint J.P. , Pruvot F.R. 
Published: April 2003

Liver grafts are spontaneously accepted in several animal combinations and are able to induce acceptance of another organ originating from the same donor, which would be rejected when transplanted alone. However, the exact mechanism of this unique tolerance induction capability remains unclear. The aim of our study was to investigate the ability of nonparenchymal liver cells to induce tolerance when they were separated from their parenchymal environment. In the murine combination we used (BN → LEW), heart transplants were constantly tolerated after combined liver plus heart grafting, but rejected when transplanted alone. Nonparenchymal liver cells were isolated from BN rat livers by enzymatic digestion and injected, at different times, to LEW rats, which were recipients of BN heart transplants. The average number of mononuclear cells obtained after isolation was 20 × 10<sup>6</sup>/5 g of rat liver. Immediate trypan-blue exclusion test showed more than 95% of viable cells. Phenotypic studies showed a predominant (47%) lymphocyte population, 7% were monocytes and 46% were cellular debris. Among the lymphocyte population, the majority of cells were bearing the NKR-P1 receptor and about 30% CD3 receptors. Inoculation of nonparenchymal liver cells 7 and 30 days prior to heart transplantation significantly prolonged graft survival compared to controls (14.6 and 12.7 vs. 8.1 days; p = 0.0008 and 0.0059, respectively), whereas simultaneous injection (day 0) had no effect. Injection of donor splenocytes or nonparenchymal liver cells from a third party, at any time, had no effect on rejection. These results provide some more evidence about the specific role of liver lymphocytes in allogenic unresponsiveness. They also suggest that the hepatic parenchymal environment is necessary for the optimal development of this phenomenon.