Evaluation of intestinal necrosis with laser Doppler in experimental mesenteric ischemia model

BACKGROUND

Acute mesenteric ischemia (AMI) is responsible for one in a thousand emergency hospital admissions in America and Europe and is associated with high morbidity and mortality rates. Current diagnostic and treatment methods fall short of desired outcomes, often resulting in delayed diagnoses and difficulties in detecting ischemic bowel tissue during treatment. This study evaluates the diagnostic value of commonly used biochemical markers in clinical practice-creatine kinase, C-reactive protein (CRP), and lactate dehydrogenase (LDH)-alongside blood flow measurements using laser Doppler in a rat model of experimental mesenteric ischemia. We also compare these markers with pathological ischemia scoring.

METHODS

Rats were divided into five groups: control, 1 hour, 2 hours, 3 hours, and 4 hours. Mesenteric ischemia was induced for the respective durations in each group. After these periods, we measured blood flow using laser Doppler. We also collected blood samples and intestinal biopsies for biochemical parameter analysis. These values were assessed in relation to intestinal viability using the Chiu ischemia scoring system.

RESULTS

Blood flow measurement with laser Doppler correlated with both the duration and severity of bowel ischemia. No significant relationship was found between CRP levels and the duration of ischemia. However, creatine kinase and lactate dehydrogenase (LDH) levels were significantly higher in ischemia lasting into the third and fourth hours.

CONCLUSION

Creatine kinase and lactate dehydrogenase (LDH) levels may be useful biomarkers in patients with suspected acute mesenteric ischemia (AMI). Blood flow measurements using laser Doppler can accurately identify intestinal loops for resection during surgery.

Local myelin damage in the hippocampus fluctuates gut microbiome profile and memory

The concept of the gut-brain axis has focused research on how gut dysbiosis affects myelin biology in the brain. However, this axis has not been tested to determine whether it conveys the effects of myelin damage on the gut microbiome profile. Therefore, we aimed to investigate how myelin biology is correlated with gut microbiome profile. The impact of local myelin damage in the hippocampus on gut microbiome profile was investigated with 16S rRNA metagenomic sequence and molecular analysis of myelin biology-associated proteins, and its reflections on memory performance were tested with behavioral tests. Local myelin damage in the hippocampus triggered severe gut dysbiosis, p < .05, changed memory performance, p < .05, and deviated emotional responses. Moreover, myelin treatment with clemastine improved gut dysbiosis and behavioral deviations. Our study provides animal-based evidence on the direct interaction between glial biology in the hippocampus and gut microbiome profile. This study proposes a framework for generating new hypotheses bridging different systems to the gut-brain axis.

Improvement of cognitive deficit of curcumin on scopolamine-induced Alzheimer's disease models

BACKGROUND

It has been suggested that curcumin may be useful in diseases with cognitive dysfunction because it slows the progression and leads to the improvement of cognitive functions. In this study, the protective effects of curcumin on scopolamine-induced rat models of cognitive impairment were evaluated.

METHODS

21 male Wistar Albino rats, 1 year old, 200±25 grams, were included in the study. They were divided into three groups (n: 7 in each group); the untreated control group, scopolamine group, and the group treated with curcumin and then exposed to scopolamine. Animals were evaluated for behavioral tasks with the Morris Water Maze test. Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), total oxidative status (TOS), and total antioxidative status (TAS) were measured in hippocampal tissues. CRP levels were measured in serum specimens.

RESULTS

We found that the length to reach the platform was the highest in the scopolamine group, and the lowest in the curcumin group (p<0.001). Time to reach the platform was the longest in the scopolamine group, and the shortest in the curcumin group (P=0.002). The length to reach the platform was the highest in the scopolamine group, and the lowest in the control group in the probe test (p<0.001). IL-6 levels were higher in the scopolamine group than the curcumin group (P=0.017) and the control group (P=0.005).

CONCLUSION

We revealed that curcumin provides a protective effect on scopolamine-induced cognitive impairment mimicking Alzheimer's disease. The use of curcumin for the protection of cognition in individuals at risk of developing AD may be considered.

The effect of tramadol on oxidative stress total antioxidant levels in rats with renal ischemia-reperfusion injury

OBJECTIVE

To evaluate the protective effect of tramadol on renal tissue in rats with induced renal ischemia-reperfusion injury (I/R injury), and its effects on oxidative stress.

MATERIAL AND METHODS

Thirty adult, male Wistar rats weighing 250-300 g were selected as subjects. Rats were randomized into 3 groups: group 1, sham; group 2, renal I/R injury; and group 3, renal I/R+Tramadol. In order to obtain ischemia in groups 2 and 3, renal artery was clamped for 1 h. Total oxidant status (TOS) and total antioxidant capacity (TAC) were analyzed using biochemical assays in the serum samples.

RESULTS

TOS values were measured as 1.68±0.4 in group 1, 3.35±1.0 in group 2, and 3.49±0.9 in group 3. When group 1 was compared with group 2 and group 3, the TOS values of group 1 were significantly lower (p<0.05), whereas there was no difference between group 2 and group 3 (p>0.05). TAC values were measured as 1.65±1.4 in group 1, 1.85±0.1 in group 2, and 2.79±0.6 in group 3. The antioxidant status of group 1 was not significantly different from that of group 2 (p>0.05), whereas there was a significant difference between group 1 and group 3 (p>0.05).

CONCLUSIONS

Tramadol has positive effects on antioxidant levels in renal I/R injury. We think that tramadol may be used in patients who underwent renal surgery and have I/R injury risk. There is a need for studies on this subject including human series.

Nigella sativa oil and thymoquinone reduce oxidative stress in the brain tissue of rats exposed to total head irradiation

Purpose: To evaluate the antioxidant and radio-protective effects of Nigella sativa oil (NSO) and thymoquinone (TQ) on radiation-induced oxidative stress in brain tissue.Materials and methods: Fifty-four Sprague-Dawley rats were divided into six groups to test the radio-protective effectiveness of Nigella sativa oil and thymoquine administered by either orogastric tube or intraperitoneal injection. Appropriate control groups were also studied.Results: Brain antioxidant capacity, as measured by the levels of total superoxide scavenger activity (TSSA), non-enzymatic superoxide scavenger activity (NSSA), superoxide dismutase, paraoxonase (PON) activities, total antioxidant status and total sulfhydryl (-SH) group, were lower in the irradiation (IR) only group while xanthine oxidase (XO) activity, total oxidant status (TOS), oxidative stress index (OSI) and lipid hydroperoxide (LOOH) levels were higher in the group compared with all other groups. Brain glutathione-S-transferase (GST) activity significantly decreased in the IR only group when compared with the control groups. Glutathione peroxidase (GSH-Px) activity was lower in the IR only, NSO plus IR, TQ plus IR groups when compared with the control group of TQ. Arylesterase (ARYL) activity was not statistically significant in the IR only group compared with all other groups.Conclusions: The results suggest that Nigella sativa oil (NSO) and its active component, TQ, clearly protect brain tissue from radiation-induced oxidative stress.

Studying the effect of large neutral amino acid supplements on oxidative stress in phenylketonuric patients

Background Oxidative stress may be one of the causes responsible for mental retardation in phenylketonuria (PKU) patients. Phenylalanine (Phe) reduces antioxidant defense and promotes oxidative stress by causing increase in reactive oxygen-nitrogen species. Our study aimed to investigate the effect of different treatments (amino acid mixture/large neutral amino acid [LNAA] supplements) on oxidative stress which are applied to late-diagnosed patients. To the best of our knowledge, this is the first study to investigate the effect of LNAA supplements on oxidative stress. Methods Twenty late-diagnosed classic PKU patients were included in this study. Patients were classified into two groups: patients under Phe-restricted diet and using Phe-free amino acid mixtures (Group I) (mean age: 13.8 ± 2.8), and patients taking LNAA supplements (Group II) (mean age: 14.8 ± 3.8). Healthy controls (mean age: 13.6 ± 4.8) with ages consistent with the ages of the patients in the experimental groups were included. Results Glutathione peroxidase is lower in patients of taking LNAA supplements than the control group (p = 0.022). Coenzyme Q10 is lower in patients of using Phe-free amino acid mixtures than the control group and it is significantly higher in Group II than Group I (p = 0.0001, p = 0.028, respectively). No significant differences were detected in total antioxidant status, total oxidant status, oxidative stress index, paraoxonase 1 and L-carnitine levels. Conclusions Different treatments affect oxidative stress parameters in PKU patients. In this study, although patients were followed up with classic PKU, patient-specific adjuvant antioxidant therapies should be implemented in response to oxidative stress.

Relationship of fibroblast growth factor 21, sirtuin 1, visfatin, and regulators in children with short stature

Fibroblast growth factor 21 (FGF21) is mainly secreted by the liver. It is a factor that is not fully understood in relation to growth. Sirtuin 1 (SIRT1) is a deacetylase protein. It is thought that may have an effect on the release and function of GH and IGF-1. Visfatin is synthesized from adipose tissue as primary. It may be prognostic marker associated with growth factors. As a result of our work, FGF21 is not associated with short stature but levels of SIRT1 and visfatin are associated with short stature. The decrease in visfatin value in the short-stature group is thought to be due to an insufficient amount of adipose tissue, which is important for growth and development. SIRT1 might decrease GH effect by increasing STAT5 deacetylation in the liver and we think that the result of this reduction of SIRT1 would negatively impact IGF-1 and IGFBP-3 production.

Effect of Blood Phenylalanine Levels on Oxidative Stress in Classical Phenylketonuric Patients

Mental retardation, which occurs in phenylketonuric patients, is associated with increased levels of phenylalanine, increased oxidative stress, and an imbalance of amino acids in the brain. Recent studies have shown that oxidative stress plays a role in the pathogenesis of phenylketonuria. In this work, we aimed to compare the influence of blood phenylalanine levels on oxidative stress parameters in phenylketonuric patients who divided patients into groups according to blood Phe levels during follow-up visits and compared these groups with healthy controls. Results showed significant differences in glutathione peroxidase (GSHPx), coenzyme Q10 (Q10), Q10/cholesterol, and L-carnitine levels in phenylketonuria patients and the control group. GSHPx, Q10, and Q10/cholesterol levels were significantly lower in poor adherence patients than in the control groups. L-carnitine levels were significantly increased in good adherence patients than poor adherence patients and decreased in poor adherence patients than healthy controls. No correlations were observed between phenylalanine and L-carnitine concentrations in poor adherence group. No significant differences were observed in paraoxonase 1 (PON1), total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) levels. As a result, in this work, poor adherence patients are prone to oxidative stress. Although the patients may have the same diagnosis, patients have different clinical characteristics and different prognosis. Antioxidants can be used as an adjuvant therapy in order to avoid neurological damage in these patients.

The effects of bupivacaine combined with different adjuvants on block onset and duration and on ion channel expressions (SCN9A, TRPM) in sciatic nerve block in rats

BACKGROUND/AIM

The objective of this experimental study was to examine the effects of epinephrine, dexmedetomidine, and clonidine added as adjuvants to bupivacaine on block onset and effect times, as well as the effects on the Na+ and Ca+2 channel gene expressions, which may indicate cell damage in the sciatic nerve cell membrane.

MATERIALS AND METHODS

Rats were divided into five groups: Group S (sham), saline solution; Group B, bupivacaine; Group BD, bupivacaine + dexmedetomidine; Group BC, bupivacaine + clonidine; and Group BE, bupivacaine + epinephrine. For each group, 0.2 mL of local anesthetic was injected into the sciatic nerve bifurcation point of the right leg. Sensory (proprioceptive and nociceptive block) and motor block onset and ending times were recorded.

RESULTS

The shortest onset time for the examined sciatic block was observed in the BC group, whereas the longest sensory and motor block times were observed in the BD group. The present data suggest suppressed TRPM7 and increased TRPM2 in the groups other than the BE group.

CONCLUSION

Clonidine is more suitable for fast onset of peripheral nerve blocks, whereas the addition of dexmedetomidine is better in terms of duration. Because the SCN9A and TRPM2,4,7 expression ratios of the BE group showed the least amount of change, this group had the best cellular integrity.

Evaluation of TRPM (transient receptor potential melastatin) genes expressions in myocardial ischemia and reperfusion

In the present study, the expression levels of TRPM1, TRPM2, TRPM3, TRPM4, TRPM5, TRPM6, TRPM7, and TRPM8 genes were evaluated in heart tissues after ischemia/reperfusion (IR). For this study, 30 albino male Wistar rats were equally divided into three groups as follows: Group 1: control group (n:10), Group II: ischemia group (ischemia for 60 min) (n:10) and Group III: IR (reperfusion 48 h after ischemia for 60 min and reperfusion for 48 h). The expression levels of the TRPM genes were analyzed by semi-quantitative reverse transcriptase-PCR. When compared to the ischemia control, the expression levels of TRPM2, TRPM4, and TRPM6 did not change, whereas that of TRPM7 increased. However, TRPM1, TRPM3, TRPM5, and TRPM8 were not expressed in heart tissue. Histopathological analysis of the myocardial tissues showed that the structures that were most damaged were those exposed to IR. The findings showed that there is a positive relationship between TRPM7 expression and myocardial IR injury.

The role of hepcidin and its related genes (BMP6, GDF-15, and HJV) in rats exposed to ischemia and reperfusion

BACKGROUND/AIM

To determine the roles of hepcidin and its related genes in a renal ischemia/reperfusion model.

MATERIALS AND METHODS

A total of 20 Wistar albino rats were equally divided into 2 groups: Group I was the control group and Group II was the ischemia and reperfusion (I/R) group (60 min of ischemia + 48 h of reperfusion). I/R was performed on the left kidneys of these rats and then the I/R-treated kidneys were removed. The levels of serum biochemical markers were evaluated after renal I/R. The expression levels of hepcidin-linked genes [growth differentiation factor 15 (GDF-15), bone morphogenetic protein 6 (BMP6), and hemojuvelin (HJV)] were also measured by RT-PCR technique. In addition, the tissues were evaluated histopathologically.

RESULTS

No significant association was found between renal dysfunction and I/R when compared to biochemical parameters (P > 0.05). However, differences in platelet values were statistically significant (P < 0.05). Expression levels of GDF-15, BMP6, and HJV genes increased, but this increase was not statistically significant. In addition, histopathological evaluation was performed using hematoxylin and eosin stain. This showed a significant relationship between the control group and I/R group for ischemic and nonischemic kidney scoring.

CONCLUSION

Hepcidin and BMP6, HJV, and GDF-15 should be taken into account when investigating the process of I/R.

Investigation of the esophageal Rho-kinase expression in patients with Barrett's esophagus

The mechanisms responsible for the malignant transformation in Barrett's esophagus (BE) are still poorly understood. The authors have evaluated the role of Rho-kinase (ROCK1 and ROCK2) expressions in patients with BE. All patients underwent upper gastrointestinal system endoscopy, which was confirmed histologically. Real-time PCR revealed no marked change in gene expressions of ROCK1 and ROCK2 at mRNA levels in BE when compared to controls. Immunohistochemical and western blot analyses showed no change in ROCK1 and ROCK2 protein expressions in BE. This study demonstrates that Rho-kinase gene and protein expressions are not modified in BE.

Preliminary study of efficacy of hyaluronic acid on caustic esophageal burns in an experimental rat model

BACKGROUND

The aim of this study was to investigate the effectiveness of hyaluronic acid on the prevention of esophageal damage and stricture formation after experimental caustic (alkaline) esophageal injury in rats.

MATERIALS AND METHODS

Twenty-one Wistar albino rats were randomly divided into three groups. A caustic esophageal burn was created following the Gehanno model: Group l (n=7) underwent operation, but no injury; Group 2 (n=7) was injured and left untreated; and Group 3 (n=7) was injured and treated with hyaluronic acid, first topically and then orally by gavage (2×0.3mL; 12.5mg/mL for 7days). The caustic esophageal burn was created by instilling 25% NaOH into the distal esophagus. All rats were euthanized on day 22 for evaluation. The efficacy of hyaluronic acid treatment was assessed histopathologically and biochemically via blood determination of the total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and sulfhydryl group (SH) and lipid hydroperoxidase (LOOH) levels. Statistical analyses were performed.

RESULTS

Weight gain was significantly lower in Group 2 than in the other two groups (P<0.05). The mean stenosis index, histopathologic damage score, TAS, TOS, OSI, and SH and LOOH levels were higher in Group 2 than in the other two groups. The mean stenosis index, inflammation, TAS, SH and OSI in Group 2 were significantly different than those in the other two groups (P<0.05).

CONCLUSION

Hyaluronic acid treatment is effective in treating damage and preventing strictures after caustic esophageal burn in rats.

Effect of cellulose acetate materials on the oxidative burst of human neutrophils

Following adverse clinical events involving seven patients undergoing renal dialysis using 12-year-old cellulose acetate hemodialyzers, this in vitro study was proposed in an effort to characterize the inflammatory response to the constituent cellulose acetate (CA) fiber materials. Chemiluminescence (CL) and apoptosis assays were used to determine whether human neutrophils were activated by CA fiber materials and/or are sensitive to degradation/alteration of these fibers over time. Furthermore, the study examined in vitro assays with human neutrophils using a CA film, the solvents used in the film preparation and CA resin. The film could be cut to identical sized pieces in an effort to compare hemodialysis material effects in standardized amounts. For the CL assays, 60-min exposure was followed by secondary stimulation with n-formyl-met-leu-phe (fMLP) or phorbol-12-myristate-13-acetate (PMA). Short-term exposure (60-min postintroduction to CA materials) increased the inflammatory response as measured by the respiratory burst of neutrophils (p < or =.05), with CA fiber exposure significantly compared with cells alone. There was a trend toward an increased response with exposure to older fibers with secondary PMA stimulation. Apoptosis was increased 12% with exposure to the more aged fibers versus 2% with the new fibers. The fiber storage component, glycerol, significantly inhibited the oxidative response (p < or =.001; > or =80% suppression with concentrations of 5-20%). The solvents used in film preparation, N,N-dimethylacetamide and tetrahydrofuran, produced greater than a 70% and 60% suppression, respectively, of CL activity for all concentrations > or =1%. More work is needed to determine the specific nature of the interaction of inflammatory cells with CA materials, but early evidence suggests that neutrophils are activated by CA and display an altered response to more aged fibers.

Expandable metal stents in achalasia--is there a role?

OBJECTIVE

Achalasia is treated with pneumatic dilation or myotomy, and botulinum toxin injections are occasionally used. We review our community's experience with expandable metal stents in six patients who failed medical treatment or were poor surgical candidates.

METHODS

Eight stents were placed in six patients between July 1995 and November 1997. Four patients had achalasia and two pseudoachalasia. Four patients underwent successive botulinum toxin injections. One patient only agreed to periodic Maloney dilatations or a stent. Pneumatic dilation was performed in one patient and considered high risk in the rest. All were poor surgical candidates. Three different stents were used: Gianturco Rosch Z stent, Wallstent I, and Wallstent II.

RESULTS

One-month mortality and morbidity were 33% and 50%, respectively. Two patients were asymptomatic on a liquid diet for > or =6 months but required repeat endoscopy for recurrent dysphagia because of food bolus impaction and proximal stent migration in each.

CONCLUSIONS

Expandable metal stents in achalasia or pseudoachalasia do not provide sustained symptom relief, and their use is associated with unacceptably high morbidity and mortality. We do not recommend the use of these devices in patients who have failed medical therapy or who are poor surgical candidates.

Expandable metal stents in achalasia--is there a role?

OBJECTIVE

Achalasia is treated with pneumatic dilation or myotomy, and botulinum toxin injections are occasionally used. We review our community's experience with expandable metal stents in six patients who failed medical treatment or were poor surgical candidates.

METHODS

Eight stents were placed in six patients between July 1995 and November 1997. Four patients had achalasia and two pseudoachalasia. Four patients underwent successive botulinum toxin injections. One patient only agreed to periodic Maloney dilatations or a stent. Pneumatic dilation was performed in one patient and considered high risk in the rest. All were poor surgical candidates. Three different stents were used: Gianturco Rosch Z stent, Wallstent I, and Wallstent II.

RESULTS

One-month mortality and morbidity were 33% and 50%, respectively. Two patients were asymptomatic on a liquid diet for > or =6 months but required repeat endoscopy for recurrent dysphagia because of food bolus impaction and proximal stent migration in each.

CONCLUSIONS

Expandable metal stents in achalasia or pseudoachalasia do not provide sustained symptom relief, and their use is associated with unacceptably high morbidity and mortality. We do not recommend the use of these devices in patients who have failed medical therapy or who are poor surgical candidates.

Irritable bowel syndrome (IBS) and alcohol abuse or dependence

Irritable bowel syndrome (IBS) has been reported in 10-22% of adults. Using a semistructured clinical interview to study the prevalence of IBS, we compared 31 patients seeking treatment for alcohol abuse or dependence in an outpatient setting with an age- and sex-matched control group of 40 patients who were seeking treatment in a general physician's office for other medical illnesses. The control group did not have any Axis I disorders. IBS was diagnosed according to the criteria of Drossman et al. Thirteen (41.9%) patients with alcohol abuse or dependence met the criteria for IBS, in contrast to 1 (2.5%) patient in the control group. We conclude that IBS is common and frequently underdiagnosed in patients with alcohol abuse or dependence.

Effect of transjugular intrahepatic portosystemic shunt on secondary hypersplenism

BACKGROUND

Portal hypertension is frequently associated with secondary hypersplenism, two common clinical manifestations of which are leukopenia and thrombocytopenia. Surgical portosystemic shunts alleviate portal hypertension but their effect on hypersplenism remains unpredictable. Transjugular intrahepatic portosystemic shunt (TIPS) is a minimally invasive procedure for portal decompression. From current reports it is not clear if TIPS improves hypersplenism in patients with portal hypertension. We present a retrospective review of our experience with TIPS to determine the effect on hypersplenism.

PATIENTS AND METHODS

Sixty-five patients who had a TIPS procedure between December 1991 and June 1994 were evaluated retrospectively. The records were specifically reviewed for platelet and white blood cell counts performed before the procedure, within a week after the procedure, and then again within the subsequent 3 weeks. Hypersplenism was defined as thrombocytopenia (platelet count of <100,000/mm3), leukopenia (white blood cell count of <5,000/mm3), or both.

RESULTS

Thrombocytopenia alone was present in 33 patients and leukopenia alone in 4 patients before TIPS was performed. Both leukopenia and thrombocytopenia were present in 12 individuals. At least one of these indices of hypersplenism was present in 49 patients. Leukocyte count improved in 11 of 16 patients (69%) whereas platelet count improved in 34 of 45 patients (75%) within a week of the procedure. In the subsequent 3 weeks, leukopenia was relieved in 5 of 10 patients (50%) and thrombocytopenia in 21 of 28 patients (75%), respectively. Of the 12 patients who had both leukopenia and thrombocytopenia before TIPS, the indices improved in 4 patients (33%) within a week of the procedure. Thrombocytopenia was more consistently corrected as opposed to leukopenia, albeit in the short term.

CONCLUSION

The TIPS procedure is a promising, minimally invasive method of portal decompression that is effective in the treatment of complications of portal hypertension including secondary hypersplenism.

Irritable bowel syndrome and dysthymia. Is there a relationship?

Irritable bowel syndrome (IBS) has been reported in 10% to 22% of adults. The authors compared patients seeking treatment for dysthymia (N = 59) in an outpatient setting to an age- and sex-matched comparison group of patients (N = 54) seeking treatment in a general physician's office for other medical illnesses. The comparison group did not have any Axis I disorders. IBS was diagnosed by using the criteria established by Drossman and colleagues. Of the patients screened, 59.32% of the patients with dysthymia met criteria for IBS in contrast to 1.85% of the comparison group (P < 0.000005). IBS is extremely prevalent in patients seeking treatment for dysthymia and is often undiagnosed and untreated.

Colonic tattooing with India ink: benefits, risks, and alternatives

OBJECTIVE

To provide comprehensive information on key issues concerning colonic tattooing with India ink in reported literature.

METHODS

A total of 735 citations on India ink alone were present in the English literature (1966-1995), including 16 on India ink and colonic tattooing. Nine major studies were identified and reviewed for 1) preparation before tattooing (type of ink used, sterilization process, colonic preparation, and antibiotic prophylaxis), 2) the tattooing process (technique and volume injected), 3) success in localization, and 4) complications.

RESULTS

A'total of 447 cases of colonic tattooing with India ink have been reported. Major indication was preoperative marking of tumor site. Various India ink preparations were used. Ink was unsterilized in 57% (255/447), autoclaved in 42% (187/447), and gas sterilized in 1% (5/447) of cases. Colonic preparation varied similarly. Prophylactic antibiotics were used in 1% (5/447) of cases. Dilution of India ink varied from undiluted to 1:100 (with 0.9% saline). The volume injected ranged from 0.1 to 2 ml per site injected, commonly with tangential needle insertion and delivery of ink into the submucosa in the majority of the cases. Intraoperative localization was easier with multiple tattoo injections. Five reports of complications have been made. In only one instance did overt clinical complications develop. Risk of a clinical complication with colonic tattooing with India ink is 0.22%.

CONCLUSION

Marked variability in technique, as well as potential for reporting bias, limit the quantitative conclusions. In general, colonic tattooing with India ink is a safe, accurate, and inexpensive method for preoperative marking and prospective study of colonic lesions.

The relationship of irritable bowel syndrome (IBS) and panic disorder

Irritable bowel syndrome (IBS) has been reported in 10 to 22% of adults. Using a semi-structured clinical interview to study the prevalence of irritable bowel syndrome, we compared 41 patients seeking treatment for panic disorder in an outpatient setting to an age- and sex-matched control group of 40 patients who were seeking treatment in a general physician's office for other medical illnesses. The control group did not have any Axis I disorders. IBS was diagnosed according to the criteria of Drossman et al. Nineteen (46.3%) patients with panic disorder met the criteria for IBS, in contrast to one (2.5%) patient in the control group (p < 0.000005). Patients with panic disorder and IBS were more likely to report symptoms of back pain as well as a personal history of bowel disease compared to patients with panic disorder but without IBS. IBS is fairly common in patients seeking treatment for panic disorder. Prospective studies should address the question whether treatment of panic disorder leads to an improvement or resolution of the symptoms of IBS.

Major depression and irritable bowel syndrome: is there a relationship?

BACKGROUND

Irritable bowel syndrome (IBS) has been reported in 10% to 22% of adults. Seventy percent to 90% of patients with IBS who seek medical attention have psychiatric comorbidity, most commonly major depression. In contrast, few studies have looked at the prevalence of IBS among psychiatric patients.

METHOD

Using a semistructured clinical interview to study the prevalence of IBS, we compared 56 patients seeking treatment for major depression in an outpatient setting to an age- and sex-matched control group of patients (N = 40) who were seeking treatment in a general physician's office for other medical illnesses. The control group had no Axis I disorders. IBS was diagnosed according to the criteria of Drossman et al.

RESULTS

Twenty-seven percent (N = 15) of patients with major depression met criteria for IBS in contrast to 2.5% (N = 1) of the control group (p = .0005). Patients with major depression and IBS were more likely to report symptoms of back pain, weakness, heartburn, and nocturnal bowel movements as well as a personal or family history of bowel disease compared with patients with major depression but without IBS.

CONCLUSION

IBS is fairly common in patients seeking treatment for major depression. Prospective studies should address the question whether treatment of major depression leads to an improvement or resolution of the symptoms of IBS.

Endoscopic US of the gastrointestinal tract with endoscopic, radiographic, and pathologic correlation

Endoscopic ultrasonography (US) makes it possible to evaluate the layers of the wall of the gastrointestinal tract, as well as surrounding structures. The authors have used endoscopic US to evaluate the gastrointestinal tract in 160 patients. In the esophagus, endoscopic US is useful in staging esophageal carcinoma, planning radiation therapy ports, and locating and characterizing esophageal masses. Endoscopic US of the esophagus is also used to identify varices and evaluate the results of therapy. Applications of endoscopic US in the stomach include staging of gastric carcinoma, localization and characterization of nonmucosal gastric masses, detection and evaluation of gastric varices, and evaluation of gastric lymphoma. In the pancreas, endoscopic US is used for detecting pancreatic masses; staging pancreatic, distal common bile duct, and ampullary carcinoma; and evaluation biliary tract obstruction. Applications of endoscopic US in the rectum include localization and characterization of nonmucosal lesions and local staging of rectal carcinoma.

Efficacy of the somatostatin analog octreotide in the treatment of two patients with refractory diabetic diarrhea

Two patients with severe refractory diabetes-related diarrhea are described. One patient had steatorrhea. Both responded to octreotide during a mean follow-up period of 7 months. The pathophysiology of diabetic diarrhea and the potential mechanism of action of octreotide are discussed. The only adverse side effect reported was hypoglycemia in one of the patients, which required a reduction of the insulin dose. Octreotide is a safe and effective agent for the treatment of refractory diabetic diarrhea.

Use of a mouth gag instrument to facilitate bite block insertion and prevent finger and probe bites during transesophageal echocardiography

Transesophageal echocardiography greatly enhances the examination of patients difficult to image transthoracically. While of low patient risk, a potential for harm from human bites to the echocardiography staff and to the transesophageal probe remains, particularly when dealing with uncooperative patients. This risk potential prompted implementation of additional anti-bite protection in our universal precautions policy beyond use of a standard mouth guard. A mouth gag instrument was modified by placing latex rubber tubing over the instrument blades. This instrument was inserted into the mouth and set in an open position giving the operator safe access for probe and mouth bite guard insertion. This technique improved access to the patient's mouth and visualization of probe insertion without the mouth bite guard. The mouth gag instrument provided an insertion of the transesophageal probe in impaired or otherwise uncooperative patients, which was safer for the patient, laboratory staff, and the probe itself.

Application of quantitative immunofluorescence to clinical serology: antibody levels of Treponema pallidum

A previously reported method of quantitative immunofluorescence, employing a calibrated photometric system and chemically stabilized fluorescence intensity, was used to replace the subjective, visual method of endpoint determination with a quantitative, calibrated measurement of antibodies to Treponema pallidum in serum. The results of the quantitative immunofluorescence method showed a 90% correlation with the subjective determinations of the visual method.

Mechanisms of gastric proton pump inhibition by calcium channel antagonists

The inhibitory effects of Ca channel antagonists on gastric acid secretion [[14C]-aminopyrine (AP) uptake ratio] have been analyzed in isolated rabbit parletal cells (PC). Secretagogue-stimulated AP uptake was inhibited by verapamil and diltiazem in a dose-dependent manner with IC50 values of 15 and 100 microM, respectively, both in the presence and absence of extracellular Ca. In contrast, nifedipine had no effect on AP accumulation. Verapamil decreased histamine-stimulated respiration with the same IC50 as observed for AP uptake. Imidazole, a weak base, by buffering the acid spaces in PC, reversed the inhibitory effect of verapamil on respiration. In the bullfrog gastric mucosa, forskolin-stimulated proton transport was inhibited by verapamil (10(-4) M) from the luminal but not the serosal side. This inhibitory effect was reversed by either elevating KCl concentration in, or removing the drug from, the secretory solution. Verapamil inhibited gastric microsomal H+,K(+)-adenosine triphosphatase (H+,K(+)-ATPase) and PC K(+)-stimulated p-nitrophenyl phosphatase activities with a higher potency than diltiazem. Inhibition of these enzymes by verapamil and diltiazem was pH dependent. The drugs competed with K+ in both H+,K(+)-ATPase and K(+)-stimulated p-nitrophenyl phosphatase reactions. Our data suggest that inhibition of the gastric proton pump by verapamil or diltiazem is not due to their Ca channel antagonism but to their interaction with the luminal high affinity K(+)-site of the H+,K(+)-ATPase under acidic conditions.

Intestinal obstruction from cecal bezoar; a complication of fiber-containing tube feedings

Dietary fiber increases stool bulk, regulates bowel transit time, and decreases intraluminal pressure. Because these actions constitute a natural way to stop diarrhea, a frequent problem with tube feedings, enteral tube feeding manufacturers have marketed several fiber-containing formulae. While bulk-forming agents such as fiber may not be appropriate for every tube-fed patient, we were unable to find any published contraindications to the use of fiber-containing enteral products. We present the case of a seriously ill man who received a fiber-containing tube feeding while also getting intestinal motility-suppressing medications. A large fiber bezoar developed, with resultant mesenteric hemorrhage. We conclude that fiber-containing tube feedings are contraindicated in certain types of patients.

Application of quantitative immunofluorescence to clinical serology: antibody levels of Toxoplasma gondii

Methods currently used for immunofluorescent reagent standardization require subjective visual comparison of reagents with control materials. Reactivities of reagents in immunofluorescence test kits vary from manufacturer to manufacturer. To solve these problems, a quantitative immunofluorescence (QIF) method which uses a calibrated photometric system and incorporates reducing agents into the mounting medium to reduce fading was developed to replace the visual method of endpoint determination. A uranyl glass slide was used to calibrate the instrument's voltage measurements, permitting daily comparisons and measurement of the instrument reading fluctuations. The QIF method was initially tailored to the determination of serum antibodies to Toxoplasma gondii by measuring the fluorescence intensity of individual tagged organisms. The nonspecific fluorescence intensity resulting from the counterstain was eliminated by use of a red-suppressing filter. The dilution-correlated polar fluorescence component was removed by subtraction of the intensity for the matching negative control dilution from each sample dilution intensity. The QIF method showed a 94% correlation with the visual comparison method for 62 clinical specimens.

Percutaneous endoscopic jejunostomy: long-term follow-up of 23 patients

This study reports our experience with the placement and long-term follow-up of 26 percutaneous endoscopic jejunostomy (PEJ) tubes in 23 patients over a 2-year period. Eighty-four percent of the PEJ tubes failed and were functional for an average of only 39.5 days. The reasons for failure were: (1) separation of the inner PEJ tube from the outer gastrostomy tube (59%); (2) clogging (32%) due to small PEJ tube diameter; and (3) kinking and knotting (9%). Upper gastrointestinal bleeding occurred in 30% of the patients (7 of 23). Only one patient required blood transfusions (2 units). The etiology of the bleeding was not determined. These patients had a previous history of acid-peptic disease and bleeding occurred despite cimetidine treatment. In contrast, only 1 of the 16 nonbleeding patients had acid-peptic disease (p less than 0.0001) and none were on cimetidine. The frequency of aspiration pneumonia decreased from 13 episodes during nasogastric tube feedings to 5 episodes during PEJ tube feedings. Improvement in the design of the PEJ tubes may increase the longevity and effectiveness of the tubes.

Quantitative immunofluorescence assay for cyclobutyldithymidine dimers in individual mammalian cells

An indirect immunofluorescence procedure was developed for the measurement of cyclobutyl dithymidine dimers in DNA of individual Syrian hamster embryo cells using a specific monoclonal antibody. A fluorescein-labeled secondary antibody and a fluorochrome which binds to DNA were used to measure the photoproduct and total DNA in the same nucleus. Fluorescence intensity was quantitated with a computer-assisted microfluorometric system which was calibrated with a uranyl oxide impregnated glass slide. Similar dose-response curves, i.e. normalized fluorescence intensity plotted as a function of dose of germicidal irradiation, were obtained with two different cell types. Normalized fluorescence intensity per nucleus was related to thymidine dimer content with a competitive enzyme-linked immunosorbent assay using DNA isolated from cells given doses of germicidal irradiation identical to those used in the immunofluorescence assay. Thymidine dimer levels produced by 10 J/m2 of germicidal irradiation (approximately 8 x 10(5)/nucleus) and which allow for 15-30% cell survival can readily be detected. The specific monoclonal antibody was labeled with tritium and used in the immunofluorescence assay to relate the number of antibodies bound to the number of thymidine dimers per cell. The data revealed that approximately 45% of the thymidine dimers in cells exposed to 100 J/m2 of germicidal irradiation and essentially all the T mean value of T in cells receiving 20 J/m2, were being detected in the indirect immunofluorescence assay. This technique can provide a sensitive means for measuring various types of DNA damage in individual cells given that the appropriate probes are available. It can be especially useful for monitoring occupationally or environmentally exposed populations where usually only small samples of cells or tissues are available.

Characterization of instrumentation and calibrators for quantitative microfluorometry for immunofluorescence tests

The current method for measuring reagents for immunofluorescence microscopy involves a subjective evaluation of the endpoint (titer) with a negative or positive (1+ to 4+) scale. Variability is due to the biological constituents of the reagent, the observer, and the instrumentation. To have reliable methods for evaluation of performance of these products, we are developing a quantitative method that uses photometric measurements of microscopically observed epifluorescence of slide preparations. A computer-controlled microscope-photometer converts the light intensity into a voltage measurement. Our goal is to replace the subjective endpoint determination with an objective, quantitative method. The instrumentation and its operating characteristics are presented in this paper. Selected commercially available fluorescent materials were evaluated as calibrators for the instrumentation. These materials showed consistency in measurement and thus demonstrated their suitability for various levels of calibration. It is possible that they will prove useful as a reference standard for interlaboratory comparisons.