Infectious causes of chronic diarrhea

Chronic diarrhea can be seen in association with specific pathogens, usually parasites and occasionally some bacteria. This article reviews pathogens causing chronic diarrhea in immunocompetent individuals and provides a rational diagnostic approach.

Is submucosal epinephrine injection necessary before polypectomy? A prospective, comparative study

BACKGROUND/AIMS

Polyps of the gastrointestinal tract are usually removed due to their link to bleeding, obstruction and malignancy. However, complications may occur following polypectomy. The aim of this study was to assess whether submucosal epinephrine injection before polypectomy could reduce the incidence of bleeding and perforation.

METHODOLOGY

Between June 1997 and November 1999, patients with sessile polyps of the gastrointestinal tract found in our endoscopic unit were randomized to receive submucosal epinephrine injection (epinephrine group) or no injection (control group) before polypectomy. In the epinephrine group, epinephrine (1:10,000) was injected surrounding the stalk of the polyp until the mucosa was blanched and bulged. The patients were observed for complications in the following month.

RESULTS

A total of 120 patients with 151 sessile polyps were enrolled in this study. In the epinephrine group, 75 polyps (n = 68) were randomized to receive epinephrine injection before polypectomy. In the control group, 76 polyps (n = 61) underwent polypectomy without epinephrine injection. In both groups, there was no significant difference in clinical features including the sizes of the polyps and their stalks, the location of polyps and the pathological diagnosis. There were a total of nine episodes of post-polypectomy hemorrhage, two in the epinephrine group and seven in the control group (2/75 vs. 7/76) (P = 0.07). One case in the epinephrine group experienced delayed bleeding (4 days later). Immediate hemorrhage occurred less in the epinephrine group than that in the control group (1/75 vs. 7/76, P = 0.03). There was one case of perforation in each group.

CONCLUSIONS

Epinephrine injection prior to polypectomy is effective in preventing immediate bleeding.

Chronic hepatitis C virus infection associated with primary warm-type autoimmune hemolytic anemia

Autoimmune hematologic abnormalities are not well recognized in chronic hepatitis C virus infection. We demonstrate an unusual association between primary autoimmune hemolytic anemia and chronic hepatitis C virus infection. A 69-year-old woman who had a history of hepatitis C virus-related liver cirrhosis was found to have deteriorating anemia with reticulocytosis when admitted to the hospital. Laboratory work revealed both positive direct and indirect Coombs' tests, and warm-type immunoglobulin G against surface antigens of red blood cells. After prednisolone therapy, her anemia improved dramatically. To our knowledge, this is the first reported case of chronic hepatitis C virus infection linked with autoimmune hemolytic anemia in its natural course, not related to prior interferon treatment. Our report suggests that isolated autoimmune hemolytic anemia may be one of the unusual hematologic manifestations of chronic hepatitis C virus infection.

Applied potential tomography in liquid gastric emptying measurement: design, assembling, calibration, and clinical application

The present study aimed to validate the accuracy of a homemade applied potential tomography (APT) apparatus for liquid gastric emptying (GE). Twelve electrodes were placed in a circular array around the subjects. Ten electrodes in a rotated order recorded electrical current delivered from a driving pair of electrodes. Based on tomography, averaged signals of changed resistivity were constructed to display area changes. Six beakers were respectively placed into a saline-filled Perspex tank to measure their cross-sections. True beaker cross-sections are 2.01, 15.9, 18.8, 30.19, 38.48, and 63.61 cm2, respectively, whereas APT generated cross-sections were 7.9 +/- 2.9, 16.7 +/- 3.3, 22.4 +/- 4.9, 28 +/- 4.8, 48.7 +/- 7.6, 67 +/- 6.1 cm2, respectively (r = 0.98, P < 0.001). Twenty-four healthy males ingested 500-ml test solution to assess GE using both APT and scintigraphy. Only 20 (83.3%) subjects had a successful measurement. The APT half emptying time was 15.6 +/- 4.8 min, whereas scintigraphy was 21.9 +/- 6.3 min (r = 0.67, P < 0.01). In conclusion, our APT apparatus is a simple, noninvasive, and inexpensive way to assess liquid GE. Its clinical usefulness is confirmed using both phantom and human models.

Role of nitric oxide in thermoregulation and hypoxic ventilatory response in obese Zucker rats

To examine the role of nitric oxide (NO) on thermoregulation and control of breathing in obesity, awake obese and age-matched lean Zucker (Z) rats underwent a sustained hypoxic challenge. Body temperature (Tb), oxygen consumption (V O(2)) and ventilation (V E) were measured during room air and during 30-min of hypoxia (10% O(2)) after intraperitoneal administration of either 100 mg/kg of N(G)-nitro-L-arginine methyl ester (L-NAME), a nonspecific NOS inhibitor, 25 mg/kg of 7-nitroindazole (7-NI), a selective neuronal NOS inhibitor, or equal volume of vehicle (dimethyl sulfoxide: DMSO) as control. Tb in obese rats during room air was significantly lower than that of lean rats. Hypoxia induced a more pronounced drop in Tb and V O(2) in lean rats than in obese rats. Tb in lean Z rats dropped significantly by approximately 0.2 degrees C after L-NAME and, more markedly, by approximately 1.1 degrees C after 7-NI compared with control during room air, whereas Tb in obese Z rats was unaffected. L-NAME and 7-NI attenuated hypoxia-induced hypothermia or hypometabolism in lean rats, but not in obese rats. Lean rats exhibited an abrupt increase in V E in response to hypoxia followed by a gradual decline in V E. In contrast, obese rats displayed an initial increase in V E that plateaued during sustained hypoxia. Both L-NAME and 7-NI induced marked decreases in V E during room air and hypoxia compared with control lean rats, whereas V E was virtually unaffected by either agent in obese rats. The present results suggest that the blunted thermoregulatory and ventilatory responses to hypoxia in obese Z rats may be attributed to reduced activity of NOS in the central nervous system.

Bacteremia after endoscopic injection of N-butyl-2-cyanoacrylate for gastric variceal bleeding

BACKGROUND

Cyanoacrylate may form a barrier that prevents bacterial invasion when used in tissue. Because cyanoacrylate polymerizes within seconds on contact with aqueous media, it is used worldwide to arrest gastric variceal bleeding. The aim of this study was to determine the frequency of bacteremia after endoscopic cyanoacrylate injection for gastric variceal bleeding.

METHODS

Patients with cirrhosis who underwent endoscopic cyanoacrylate injection for gastric variceal bleeding were included. Patients with cirrhosis who underwent upper endoscopy for nonvariceal upper GI bleeding were recruited as controls. Patients with infection before endoscopy were excluded. Blood was cultured in both groups. Injection needles and endoscope accessory channels were cultured in the cyanoacrylate injection group.

RESULTS

More patients injected with cyanoacrylate had positive blood cultures in comparison with the control group (15/47 vs. 1/47, p < 0.0001). In the cyanoacrylate injection group, the volume of blood transfused and Child-Pugh score were factors associated with the occurrence of bacteremia. Most episodes of bacteremia were transient, except for 1 patient who died of sepsis. Most of the microorganisms cultured from blood samples were identical to those cultured from injection needles (65%) and accessory channels (90%).

CONCLUSIONS

Endoscopic cyanoacrylate injection for gastric varices does not limit the spread of bacteria. The endoscope accessory channel was the major source of bacteria. Most episodes of bacteremia were transient and uneventful.

Bilateral sudden deafness as a prodrome of anterior inferior cerebellar artery infarction

BACKGROUND

Acute ischemic stroke in the distribution of the anterior inferior cerebellar artery is known to be associated with hearing loss, facial weakness, ataxia, nystagmus, and hypalgesia. There have been few reports on bilateral deafness and vertebrobasilar occlusive disease. Furthermore, previous reports have not emphasized the inner ear as a localization of bilateral deafness.

OBJECTIVE

To describe the presentation of acute ischemic stroke in the distribution of the anterior inferior cerebellar artery as sudden bilateral hearing loss with minimal associated signs.

DESIGN AND SETTING

Case report and tertiary care hospital.

PATIENT

A 66-year-old man with diabetes mellitus developed sudden bilateral deafness, unilateral tinnitus, and vertigo 7 days before the onset of dysarthria, facial weakness, and ataxia. T2-weighted magnetic resonance imaging scans showed hyperintensities in the right lateral pons and right middle cerebral peduncle and a possible abnormality of the left middle cerebellar peduncle. A magnetic resonance angiogram showed moderately severe stenosis of the distal vertebral artery and middle third of the basilar artery. The patient's right limb coordination and gait improved steadily over several weeks, but there was no improvement in hearing in his right ear.

CONCLUSIONS

The relatively isolated onset of deafness as well as the severity and persistence of the hearing loss led us to conclude that the hearing loss in this case was likely due to prominent hypoperfusion of the internal auditory artery, with labyrinthine infarction as the earliest event. Vertebrobasilar occlusive disease should be considered in the differential diagnosis of sudden bilateral deafness.

Cigarette smoke extract induces endothelin-1 via protein kinase C in pulmonary artery endothelial cells

We examined the mechanism of endothelin (ET)-1 regulation by cigarette smoke extract (CSE) and the effect of platelets on CSE-induced stimulation of ET-1 gene expression in human and bovine pulmonary artery endothelial cells (PAECs). Our data show that CSE (1%) induces ET-1 gene expression (after 1 h) and ET-1 peptide synthesis (after 4 h) in bovine PAECs. The induction of preproET-1 mRNA level was due to de novo transcription, and new protein synthesis was not required for this induction. The protein kinase C inhibitors staurosporine (10(-8) mol/l) and calphostin C (10(-7) mol/l) abolished the induction of ET-1 gene expression by CSE in bovine and human PAECs. Although a lower concentration of platelets (10(6) cells/ml in bovine PAECs; 10(7) cells/ml in human PAECs) did not significantly alter ET-1 gene expression in PAECs, incubation of platelets with CSE (1%) and PAECs produced a significant increase in preproET-1 mRNA and ET-1 peptide compared with the values in the presence of CSE (1%) alone. CSE (1%) induced platelet aggregation and increased the expression of platelet membrane glycoproteins ex vivo. Thus our data suggest that CSE stimulates ET-1 gene expression via PKC in PAECs. CSE and platelets showed a synergistic effect on ET-1 gene expression, possibly through the activation of platelets by CSE.

Electrogastrographic characteristics in patients of stomach cancer

Using a homemade electrogastrography (EGG) system, we studied the characteristics of myoelectrical rhythm in gastric cancer (GC) patients. Based on a short-term Fourier transform, recorded slow waves could be automatically analyzed to obtain the following parameters: dominant frequency/power, percent of normal rhythm (2.4-3.7 cpm), power ratio, etc. Fifty histologically confirmed GC patients (34 men, 16 women) were enrolled before surgical intervention to measure their fasting and postprandial EGG parameters for 30 min. The cancerous parameters of GC patients were then obtained postoperatively. In addition, 46 healthy subjects were enrolled for comparison. When compared to controls, GC patients had the following characteristics: absence of postprandial increase in dominant frequency (GC: 3.04 +/- 0.47 vs 3.07 +/- 0.44 cpm, NS; controls: 3.02 +/- 0.31 vs 3.21 +/- 0.25 cpm, P < 0.001), marked power response after meal (P < 0.05), and obvious power ratio (4.58 +/- 7.38 vs 2.27 +/- 2.05, P < 0.05). Multivariate analysis indicated that advanced GC was the factor responsible for the obvious dominant power enhancement after meal (P < 0.05). Other demographic, clinical, and cancerous factors did not influence EGG parameters. We conclude that apparent arrhythmia is not encountered in GC patients, although they mainly exhibit obvious postprandial power response. Advanced GC is likely responsible for this power enhancement on EGG recording.

NMDA receptor-mediated modulation of ventilation in obese Zucker rats

BACKGROUND

Ventilation in response to hypoxia is reduced in some obese humans and is believed to represent part of the pathogenesis of obesity hypoventilation syndrome (OHS). Ventilation in response to hypoxic exposure is closely related to the release of excitatory neurotransmitters, in particular glutamate, acting specifically on N-methyl-D-aspartate (NMDA) receptors.

OBJECTIVES

The aim of the present study was to investigate whether NMDA receptor-mediated mechanisms are responsible for the altered ventilatory response to sustained hypoxia observed in obese Zucker (Z) rats.

SUBJECTS

Seven lean and seven 15-week-old obese male Z rats were studied.

MEASUREMENTS

Ventilation ([V](E)) at rest and during 30 min sustained hypoxic (10% O(2)) exposure was measured by the barometric method. [V](E) was assessed following the blinded-random administration of equal volumes of either saline (vehicle) or dextromethorphan (DM, 10 mg/kg), a non-competitive glutamate NMDA receptor antagonist.

RESULTS

DM had no effects on resting [V(E) in both lean and obese rats during room air breathing. Lean rats treated with DM exhibited a significant (P<0.05) depression in [V](E), V(T), and V(T)/T(I) during either the early (5 min) or the late phase (30 min) of ventilatory response to sustained hypoxia. In contrast, DM administration in obese rats did not change [V(E), V(T), or V(T)/T(I) during the early phase of ventilatory response to hypoxia. During the late phase of ventilatory response to hypoxia. obese rats treated with DM exhibited a similar depression in [V](E) and V(T) as observed in lean rats, but had no significant change in V(T)/T(I) during the 30 min hypoxic exposure.

CONCLUSION

Our findings indicate that altered glutamatergic mechanisms acting on NMDA receptors are partially responsible for a blunted early phase of ventilatory response to hypoxia noted in obese rats and also contribute to their reduced neural respiratory drive.

A 3-day anti-Helicobacter pylori therapy is a good alternative for bleeding peptic ulcer patients with Helicobacter pylori infection

BACKGROUND/AIMS

One-week triple therapy has been recommended as a standard regimen for eradicating Helicobacter pylori infection. The emergence of antibiotic-resistant strains, adverse drug effects, poor compliance and high cost of therapy add problems to the management of these patients. In this study, we assessed whether a 3-day triple therapy could be effective in eradicating Helicobacter pylori infection in bleeding peptic ulcer patients.

METHODOLOGY

Peptic ulcer patients with Helicobacter pylori infection were enrolled in this study. Patients enrolled at the outpatient department (group A) received a 7-day oral regimen: bismuth subcitrate colloid 300 mg + amoxicillin 500 mg + metronidazole 250 mg four times per day. Patients who were admitted to the wards due to peptic ulcer bleeding (group B) received a 3-day regimen including omeprazole 40 mg intravenously every 6 hours, amoxicillin 500 mg + metronidazole 250 mg orally four times daily after hemostasis had been achieved. Patients of both groups received omeprazole 20 mg once per day or cimetidine 400 mg twice daily per os for at least-one month after anti-Helicobacter pylori therapy. We followed every patient endoscopically two months after anti-Helicobacter pylori therapy.

RESULTS

From June 1997 to April 1999, a total of 57 patients (30 in group A and 27 in group B) with gastric or duodenal ulcer and Helicobacter pylori infection completed anti-Helicobacter pylori therapy. Two months after anti-Helicobacter pylori therapy, peptic ulcer was found to be healed with a scar in 26 (86.7%) of group A and 23 (85.2%) of group B (P > 0.1). The eradication rates of Helicobacter pylori in the two groups were not significantly different in an intention-to-treat analysis [group A: 78.8% (26/33), 95% CI: 64.9-92.7%; group B: 80% (24/30), 95% CI: 65.7-94.3%, P > 0.1] and in a per protocol analysis [group A: 86.7% (26/30), 95% CI: 74.5-98.9%, group B: 88.9% (24/27), 95% CI: 77.1-100.7%, P > 0.1]. Fewer side effects occurred in group B (3/30) than those in group A (7/33) (P > 0.1).

CONCLUSIONS

In patients with peptic ulcer bleeding a 3-day anti-Helicobacter pylori therapy is a good alternative for eradicating Helicobacter pylori infection.

Opioidergic modulation of ventilatory response to sustained hypoxia in obese Zucker rats

OBJECTIVE

To determine whether altered central and/or peripheral opioidergic mechanisms contribute to the altered ventilatory response to sustained hypoxia in obese Zucker rats.

RESEARCH METHODS AND PROCEDURES

Eight lean (176 +/- 8 [SEM] g) and eight obese (225 +/- 12 g) Zucker rats were studied at 6 weeks of age. Pulmonary ventilation ((E)), tidal volume (V(T)), and breathing frequency (f) at rest and in response to sustained (30 minutes) hypoxic (10% O(2)) challenges were measured on three separate occasions by the barometric method after the randomized, blinded administration of equal volumes of saline (control), naloxone methiodide (N(M); 5 mg/kg, peripheral opioid antagonist), or naloxone hydrochloride (N(HCl); 5 mg/kg, peripheral and central opioid antagonist).

RESULTS

Administration of N(M) and N(HCl) in lean animals had no effect on (E) either at rest or during 30 minutes of sustained exposure to hypoxia. Similarly, N(M) failed to alter (E) in obese rats. In contrast, N(HCl) significantly (p < 0.05) increased (E) and V(T) both at rest and during 2 to 10 minutes of hypoxic exposure in obese rats. After 20 to 30 minutes of hypoxic exposure, V(T) remained elevated with N(HCl), but the earlier elevation of (E) seemed to be attenuated due to a decrease in f at 20 minutes of exposure to hypoxia.

DISCUSSION

Thus, endogenous opioids modulate both resting (E) and the ventilatory response to sustained hypoxia in obese, but not in lean, Zucker rats by acting specifically on opioid receptors located within the central nervous system.

Adaptive vasodilatory response after octreotide treatment

Despite the suppression of glucagon release, an adaptive response aimed at maintaining vasodilatation after octreotide treatment may exist in portal hypertension. The present study was undertaken to evaluate the possible interaction between endothelium and non-endothelium-derived vasodilators after 1-wk octreotide administration in cirrhotic rats. Rats were allocated to receive either vehicle or octreotide (30 or 100 microg/kg every 12 h subcutaneously). Hemodynamic values, plasma glucagon levels, endothelium-related vasodilatory activities, and aortic endothelial nitric oxide synthase (eNOS) expression were determined after treatment. Octreotide administration decreased plasma glucagon and increased serum 6-keto-PGF(1 alpha) and NOx levels without affecting the hemodynamic values. In cirrhotic rats receiving octreotide, there was a blunt response to either L-NAME or indomethacin administration alone, but this blunt pressor response disappeared after simultaneous administration of the two drugs. Additionally, an increased aortic eNOS expression was observed in cirrhotic rats receiving 1-wk octreotide. It is concluded that 1-wk octreotide treatment did not correct the hemodynamic derangement in cirrhotic rats. The enhanced endothelium-related vasodilatory activity was noted after octreotide treatment that overcame the octreotide-induced hemodynamic effects in portal hypertension.

The pharmacological effect of omeprazole on water gastric emptying: A study based on an impedance measure

The present study was performed to validate the accuracy of a self-designed applied-potential tomograph (APT) in measuring the cross area of a studied object and to assess the effect of omeprazole premedication on water gastric emptying (GE), based on APT. Twelve electrodes were evenly placed in a circular array around the studied subjects. Ten electrodes in a rotated order recorded the electrical current injected into paired electrodes. Based on tomography, averaged signals of changed resistivity were constructed to display the area of interest and GE curve. Six beakers of various diameters were respectively placed into a cylindrical perspex tank which was filled with saline to measure their cross areas via computer-generated diagrams of APT. One hour after either omeprazole (20 mg) or placebo premedication, 15 healthy males were ordered to consume 500 ml of test water to assess emptying for 40 min. Within 3 days, a similar procedure was repeated using the counterpart premedication. The true cross areas of the 6 beakers are 2.01, 15.9, 18.8, 30.19, 38.48 and 63.61 cm(2), whereas those obtained by APT were 7.9 +/- 2.9, 16.7 +/- 3.3, 22.4 +/- 4.9, 28 +/- 4.8, 48.7 +/- 7.6 and 67 +/- 6.1 cm(2), respectively (r = 0.98, p < 0.001). Valid emptying data were obtained in 73.3 and 86.6% of subjects, following placebo and omeprazole, respectively (not significant). The half emptying times were 12.7 +/- 5.1 min for the placebo-treated group and 10.5 +/- 3.6 min for the omeprazole-treated group, respectively (p < 0.05). The areas under the emptying curve were 1,611.5 +/- 357.6 and 1,317.3 +/- 316.7 arbitrary units, respectively (p < 0.01). In conclusion, our APT system is accurate for large-area measurements; acid inhibition before APT measurement does not increase the success rate but enhances water emptying. The interpretation of impedance-obtained GE should consider the acid-inhibitory effect.

Pseudonocardia kongjuensis sp. nov., isolated from a gold mine cave

The taxonomic position of an isolate that was recovered from a gold mine cave near Kongju, Republic of Korea, was determined by 16S rDNA sequence studies and chemotaxonomic characterization. Comparative studies of 16S rDNA sequences indicated that this organism was phylogenetically related to members of the genus Pseudonocardia, branching outside a cluster encompassing Pseudonocardia autotrophica and Pseudonocardia compacta. The affiliation to the genus was also supported by the cell chemistry, which was represented by a type IV cell wall, MK-8(H4) as the major menaquinone, a phospholipid type PIII pattern (phosphatidylcholine as a diagnostic phospholipid) and a DNA G+C content of 71 mol%. The fatty acid profile contained saturated, unsaturated and 10-methyl branched fatty acids, but tuberculostearic acid and hydroxy fatty acids were not present. The isolate differed from its phylogenetic neighbours in the presence of phosphatidylethanolamine, dodecanoate, 16-methylheptadecenoate and 16-methylheptadecanoate and the absence of phosphatidylinositol mannoside and phosphatidylmethylethanolamine. The unique combination of physiological properties, the cellular fatty acid profile and DNA-DNA hybridization data indicates that this organism is readily differentiated from the type strains of all of the validly published species of the genus Pseudonocardia. The name Pseudonocardia kongjuensis sp. nov. is proposed for the type strain, LM 157T (= IMSNU 50583T = KCTC 9990T = DSM 44525T).

Feasibility and potential benefit of maintenance endoscopic variceal ligation in patients with unresectable hepatocellular carcinoma and acute esophageal variceal hemorrhage: a controlled trial

BACKGROUND

Patients with unresectable hepatoma and acute esophageal variceal bleeding have extremely high rates of recurrent bleeding and mortality. This controlled study evaluates the feasibility and potential benefit of maintenance endoscopic variceal ligation in these patients.

METHODS

Patients with unresectable hepatoma and acute esophageal variceal bleeding underwent emergent endoscopic variceal ligation. After hemostasis, patients were randomized to undergo maintenance or esophageal variceal ligation (EVL) as necessary (demand ligation).

RESULTS

Fifty-four patients underwent maintenance EVL and 55 demanded EVL. One or more subsequent EVL session could be performed in only 30 patients (55.6%) in the maintenance group (actual maintenance ligation). Logistic regression analysis found that hepatic function determines the feasibility of maintenance ligation (Child-Pugh's A+B vs. C, OR 23.00: 95% CI [5.26, 100.66]). The survival and recurrent bleeding rates were similar in both groups. A subgroup analysis of patients with Child-Pugh's A and B hepatic reserve in both the maintenance EVL group (n = 24) and demand EVL group (n = 25) was performed to assess the potential benefit of maintenance ligation. Maintenance ligation reduced the rate of recurrent bleeding compared with demand ligation (p = 0.043). Cox regression showed that portal vein thrombosis and tumors in both hepatic lobes were also factors together with EVL that determined recurrence of bleeding. Survival was similar in both groups.

CONCLUSIONS

Maintenance ligation is feasible in patients with unresectable hepatoma and variceal hemorrhage if they have a good hepatic reserve. Maintenance ligation might lower the rate of recurrent bleeding in this subgroup of patients.

Hepatic encephalopathy in rats with thioacetamide-induced fulminant hepatic failure: role of endotoxin and tumor necrosis factor-alpha

BACKGROUND

Hepatic encephalopathy, a complex neuropsychiatric syndrome secondary to acute liver failure, chronic parenchymal liver disease or portal-systemic shunting, may possibly develop through mediators of endotoxin and tumor necrosis factor-alpha (TNF-alpha). However, there are no published data concerning the relationships between the severity of encephalopathy and the plasma levels of endotoxin and TNF-alpha.

METHODS

Male Sprague-Dawley rats weighing about 300-350 g were used. Fulminant hepatic failure was induced by intraperitoneal injection ofthioacetamide (350 mg/kg/day) for 3 consecutive days. Severity of encephalopathy was assessed by measuring motor counts using an Opto-Varimex animal activity meter. Plasma levels of endotoxin and TNF-alpha were determined by chromogenic Limulus assay and ELISA method, respectively.

RESULTS

Our study revealed that higher plasma levels of endotoxin (> 5.9 pg/ml) and TNF-alpha (> 18.8 pg/ml) were significantly associated with more blunted motor activities in rats with fulminant hepatic failure (p < 0.05). A significant correlation was observed between plasma concentrations of endotoxin and TNF-alpha (r = 0.59, p < 0.001). Plasma levels of endotoxin were weakly correlated with the total movements in an open field (r = -0.34, p = 0.032) and the counts of ambulatory (r = -0.38, p = 0.014) and vertical movements (r = -0.40, p = 0.010). There were no correlations between the motor counts and plasma levels of TNF-alpha (p > 0.05).

CONCLUSIONS

In addition to endotoxin and TNF-alpha, other factors may participate in the pathogenesis of hepatic encephalopathy in rats with thioacetamide-induced fulminant hepatic failure.

Effects of heat pretreatment on histopathology, cytokine production, and surfactant in endotoxin-induced acute lung injury

To determine the effect of heat stress on histopathology of acute lung injury (ALI) caused by administration of lipopolysaccharide (LPS), and to determine the roles of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, IL-10 and surfactants in heat-induced tolerance to ALI, we administered either saline or LPS (3 mg/kg of body weight) intravenously to male Sprague-Dawley rats without and with heat pretreatment. Five hours after LPS or saline treatment (23 h after heat-pretreatment), samples were obtained. We found that the histopathologic features of LPS-induced ALI were attenuated by heat-pretreatment. Heat-pretreatment did not decrease the elevated plasma or BAL fluid levels of TNF-alpha, IL-1beta, and IFN-gamma by LPS. The plasma level of IL-10 in LPS-treated rats with heat-pretreatment, however, was increased compared to that of LPS-treated rats without heat-pretreatment (P = 0.001). There were no differences in the BAL fluid concentrations of light or heavy density pulmonary surfactant phospholipids depending on heat-pretreatment in LPS-treated rats. These observations suggest that IL-10 might play a role in decreasing LPS-induced acute lung injury after heat-pretreatment.

Mechanistic scheme and effect of "extended sigh" as a recruitment maneuver in patients with acute respiratory distress syndrome: a preliminary study

OBJECTIVE

To devise a new form of sigh ("extended sigh") capable of providing a sufficient recruiting pressure x time, and to test it as a recruitment maneuver in patients with acute respiratory distress syndrome.

DESIGN

Prospective uncontrolled clinical trial.

SETTING

Medical intensive care unit of a university-affiliated hospital.

PATIENTS

Twenty consecutive patients diagnosed with acute respiratory distress syndrome (18 men, 2 women, age 59 +/- 10 yrs).

INTERVENTIONS

From baseline settings of tidal volume (Vt) 8 mL/kg and positive end-expiratory pressure (PEEP) 10 cm H2O on volume control mode with the high pressure limit at 40 cm H2O, the Vt-PEEP values were changed to 6-15, 4-20, and 2-25, each step being 30 secs (inflation phase). After Vt-PEEP 2-25, the mode was switched to continuous positive airway pressure of 30 cm H2O for a duration of 30 secs (pause), after which the baseline setting was resumed following the reverse sequence of inflation (deflation phase). This extended sigh was performed twice with 1 min of baseline ventilation between.

MEASUREMENTS AND RESULTS

Airway pressures and hemodynamic parameters were traced at each step during the extended sigh. Arterial blood gases and physiologic parameters were determined before the extended sigh (pre-extended sigh), at 5 mins after two extended sighs (post-extended sigh), and then every 15 mins for 1 hr. In our average patient, the recruiting pressure x time of the inflation phase was estimated to be 32.8-35.4 cm H2O x 90 secs. Compared with the inflation phase, inspiratory pause pressure of the deflation phase was lower at Vt-PEEP 6-15 (28.9 +/- 2.7 cm H2O vs. 27.3 +/- 2.8 cm H2O) and 4-20 (31.8 +/- 2.9 cm H2O vs. 31.1 +/- 2.9 cm H2O; both p <.05). Compared with pre-extended sigh, Pao2 (81.5 +/- 15.3 mm Hg vs. 104.8 +/- 25.0 mm Hg; p <.001) and static respiratory compliance both increased post-extended sigh (27.9 +/- 7.9 mL/cm H2O vs. 30.2 +/- 9.7 mL/cm H2O; p =.009). Improvement in these parameters was sustained above pre-extended sigh for the duration of the study. Major hemodynamic or respiratory complications were not noted during the study.

CONCLUSION

We present a new form of sigh (i.e., extended sigh) capable of achieving an augmented recruiting pressure x time through a prolonged inflation on a gradually increased end-expiratory pressure. In view of the sustained effect and absence of major complications in our patients, extended sigh could be a useful recruitment maneuver in acute respiratory distress syndrome.

Lung cancer in patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) was reported to be associated with increased risk of lung cancer as a result of the occurrence of atypical or dysplastic epithelial changes in fibrosis which progressed to invasive malignancy. In that situation, the cancer will develop in the area of major fibrosis. To investigate the direct relationship between fibrosis and cancer development, the real concordance rate of the two lesions in the chest computed tomography (CT) was analysed and compared to the histological types of lung cancer. The subjects included 63 patients with combined lung cancer and IPF (IPF-CA), 218 patients with lone IPF, and 2,660 patients with primary lung cancer. All patients were diagnosed at Asan Medical Center during the same period. The age, percentage of smokers, and the male sex were significantly higher in IPF-CA compared with lone IPF. The odds ratio of smoking was 2.71 compared to nonsmoking IPF controls. In IPF-CA, 56% of the cancer was located in the periphery of the lung and 52% in the upper lobe. The majority of the cancers (64%) were found in the nonfibrotic area at chest CT. The most frequent cell type was squamous cell carcinoma (35%), and there was no significant difference in the cancer cell type between IPF-CA and total lung cancer population. These findings suggest that in combined lung cancer and idiopathic pulmonary fibrosis patients, the features of the lung cancer are similar to the total lung cancer population.

Clinical, virological, and pathological significance of hepatic bile duct injuries in Chinese patients with chronic hepatitis C

PURPOSE

Hepatic bile duct injuries are characteristic histological findings in patients with chronic hepatitis C virus (HCV) infection. However, the pathogenesis and clinical significance of this phenomenon remain unclear. The aims of this study were to evaluate the prevalence and clinical significance of hepatic bile duct injuries in Chinese patients with chronic hepatitis C.

METHODS

One hundred and seventeen Chinese patients with chronic hepatitis C were enrolled. Clinical, biochemical, immunological (serum autoantibodies and cryoglobulinemia), histological, and virological data (serum HCV RNA titer and HCV genotype) were compared between patients with and without hepatic bile duct injuries.

RESULTS

Eighty-three (71%) of the 117 patients with chronic hepatitis C had hepatic bile duct injuries. Patients with hepatic bile duct injuries had a significantly higher frequency of HCV genotype 1b; a higher mean serum globulin level; significantly higher mean scores for histological periportal necro-inflammation, portal inflammation, and fibrosis; and more severe portal lymphoid aggregation/follicles when compared with patients without hepatic bile duct injuries (P < 0.05, all). No significant differences in the presence of serum autoantibodies, cryoglobulinemia, mean serum HCV RNA titer, or response to interferon treatment were noted between the two groups. Multivariate logistic regression analysis showed that HCV genotype 1b infection, portal inflammation, and lymphoid aggregation/follicles were significant independent predictors associated with hepatic bile duct injuries.

CONCLUSIONS

The presence of hepatic bile duct injuries in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection, and the patients with these injuries had more severe portal inflammation and formation of lymphoid aggregates/follicles.

A new "sandwich" method of combined endoscopic variceal ligation and sclerotherapy versus ligation alone in the treatment of esophageal variceal bleeding: a randomized trial

BACKGROUND

Variceal ligation is the optimum endoscopic method for treating esophageal variceal bleeding. However, both early and multiple recurrences of esophageal varices frequently follow ligation. The aim of this randomized study was to determine whether a new, combined endoscopic "sandwich" method (i.e., ligation-sclerotherapy-ligation) could achieve better results than ligation alone.

METHODS

Ninety-four patients with cirrhosis and acute or recent esophageal variceal bleeding were randomized to undergo either the "sandwich" method or ligation alone (47 patients in each group).

RESULTS

The sclerosant was retained in the varices for more than 30 minutes in 7 of 8 patients undergoing the "sandwich" method plus radiographic contrast medium. Active bleeding was controlled with this new method (9/9) as efficiently as ligation (12/12). The rate of recurrent bleeding was similar for both methods. Multivariate analysis showed the necessity for the use of antibiotics (odds ratio 3.95: 95% CI [1.60, 9.76]) to be an independent factor for recurrent bleeding. Two patients in the "sandwich" group developed strictures, but the frequency of other complications did not differ between the 2 groups. Kaplan-Meier analysis showed the cumulative probability of variceal recurrence was lower with the "sandwich" method (p = 0.0391). The survival rate and causes of death were similar in both groups.

CONCLUSIONS

The "sandwich" method leads to longer retention of sclerosant in varices. This method is superior to ligation alone in terms of lower variceal recurrence rate and comparable to ligation with respect to hemostasis. However, it is unknown whether the lower recurrence rate of varices will persist long-term.