Fusarium proliferatum, an endophytic fungus from Dysoxylum binectariferum Hook.f, produces rohitukine, a chromane alkaloid possessing anti-cancer activity

Rohitukine is a chromane alkaloid possessing anti-inflammatory, anti-cancer and immuno-modulatory properties. The compound was first reported from Amoora rohituka (Meliaceae) and later from Dysoxylum binectariferum (Meliaceae) and Schumanniophyton problematicum (Rubiaceae). Flavopiridol, a semi-synthetic derivative of rohitukine is a potent CDK inhibitor and is currently in Phase III clinical trials. In this study, the isolation of an endophytic fungus, Fusarium proliferatum (MTCC 9690) from the inner bark tissue of Dysoxylum binectariferum Hook.f (Meliaceae) is reported. The endophytic fungus produces rohitukine when cultured in shake flasks containing potato dextrose broth. The yield of rohitukine was 186 μg/100 g dry mycelial weight, substantially lower than that produced by the host tissue. The compound from the fungus was authenticated by comparing the LC-HRMS and LC-HRMS/MS spectra with those of the reference standard and that produced by the host plant. Methanolic extract of the fungus was cytotoxic against HCT-116 and MCF-7 human cancer cell lines (IC(50) = 10 μg/ml for both cancer cell lines).

Endophytic fungal strains of Fusarium solani, from Apodytes dimidiata E. Mey. ex Arn (Icacinaceae) produce camptothecin, 10-hydroxycamptothecin and 9-methoxycamptothecin

Camptothecin and 10-hydroxycamptothecin are two important precursors for the synthesis of the clinically useful anticancer drugs, topotecan and irinotecan. In recent years, efforts have been made to identify novel plant and endophytic fungal sources of camptothecin and 10-hydroxycamptothecin. In this study we have isolated endophytic fungi strains from Apodytes dimidiata (Icacinaceae), a medium sized tree from the Western Ghats, India. The fungi were identified as Fusarium solani using both ITS rDNA sequencing and spore morphology. Two strains, MTCC 9667 and MTCC 9668 were isolated, both of which produced camptothecin and 9-methoxycamptothecin in their mycelia; one of the strains, MTCC 9668 also produced 10-hydroxycamptothecin, though in small amounts. The yields of camptothecin in MTCC 9667 and MTCC 9668 were 37 and 53 microg/100g, respectively, after 4 days of incubation in broth culture. The yields of 10-hydroxycamptothecin and 9-methoxycamptothecin in MTCC 9668 were 8.2 and 44.9 microg/100g, respectively. Further research in optimizing the culture conditions of these fungal strains might permit their application for the production of camptothecin and 10-hydroxycamptothecin.

The effect of stimulant laxatives and polyethylene glycol-electrolyte lavage solution for colonoscopy preparation on serum electrolytes and hemodynamics

We have previously shown that magnesium citrate or bisacodyl before polyethylene glycol electrolyte lavage solution (PEG-ELS) improves colonoscopy preparation. Patients prefer this to preparation with full-volume PEG-ELS alone. However, such combinations might cause undesirable changes in hemodynamics or serum electrolytes. This study examined the effects of these combinations on heart rate, blood pressure, and serum electrolytes. We randomized 68 consecutive patients undergoing colonoscopy to one of three preparations. Group 1 received 4 L of PEG-ELS, group 2 received 2 L of PEG-ELS with 20 mg bisacodyl, and group 3 received 2 L of PEG-ELS preceded by 296 mL of magnesium citrate. Heart rate, blood pressure, and serum electrolytes were measured before starting the preparation and immediately before colonoscopy. Mean serum magnesium fell by 0.01 mg/dL and 0.11 mg/dL in groups 1 and 2, respectively, and rose by 0.06 mg/dL in group 3 (p = 0.044). There were no other significant changes. Statistically significant changes in serum magnesium after preparation with PEG-ELS and a stimulant laxative are minor and probably of no clinical relevance. Two liters of PEG-ELS with a stimulant laxative is safe and effective for colonoscopy.

Changes in colorectal cancer over a 15-year period in a single United States city

OBJECTIVE

The aim of this study was to identify colorectal cancer trends in different patient groups in one region.

METHODS

We reviewed the records of all patients with colorectal cancer who were seen at two hospitals in Columbia, SC, between 1981 and 1995. Patients were divided into three 5-yr cohorts (cohort 1, 1981-1985; cohort 2, 1986-1990; and cohort 3, 1991-1995). We recorded demographic data, histological type, tumor stage, grade, and survival.

RESULTS

A total of 1395 patients were diagnosed, of whom 1252 had adenocarcinoma. Mean age of diagnosis was 64.5 yr in black and 66 in white patients (p = 0.036). Adenocarcinoma proximal to the splenic flexure was found in 62% of women and 49% of men (p < 0.001), and in 51% of black and 44% of white patients (p = 0.08). Proximal cancers accounted for 61%, 48%, and 32% of cohorts 1, 2, and 3, respectively. The proportions of patients with advanced stage (III and IV) adenocarcinoma in the three cohorts were 54%, 47%, and 40%, respectively (p = 0.001). Median survival for adenocarcinoma was 23.7, 23.5, and 23.1 months in cohorts 1, 2, and 3 (p = 0.9).

CONCLUSIONS

The prevalence and demographics of colorectal cancer have been fairly stable at this center. There has been a significant decrease in proximal cancers. Although adenocarcinoma is being diagnosed at an earlier stage, this has not affected survival. Colonoscopy may be the most appropriate screening method in women and in black patients, in whom proximal cancers are more often found.

Colorectal cancer screening and surveillance practices by primary care physicians: results of a national survey

OBJECTIVE

Screening for colorectal cancer reduces its morbidity and mortality and is cost-effective. Screening is usually the responsibility of primary care physicians who may be unsure about its implementation. We aimed to assess primary care physicians' knowledge and practice regarding colorectal cancer screening, and to compare their responses with those of three national experts and with published guidelines.

METHODS

We mailed a postal questionnaire to 2,310 primary care physicians regarding demographics, nature of practice, use of screening tests, and six hypothetical patients who may have been candidates for screening or surveillance. We used published national guidelines and the collective opinions of the three external experts as the so-called "gold standard."

RESULTS

Of all respondents, 85.1% offered colorectal cancer screening. Most used suitable tests, starting at an appropriate age; 49.8% continued screening indefinitely irrespective of patients' age and 43.6% performed fecal occult blood testing without appropriate dietary advice to patients. Also, respondents frequently performed this test for inappropriate indications. Only 51.8% would follow a positive fecal occult blood test with colonoscopy.

CONCLUSIONS

Colorectal cancer screening practices by primary care physicians vary considerably from those recommended. Many offer screening to individuals in whom it is not appropriate, and continue it into advanced age. Frequent, inappropriate use of fecal occult blood tests will produce many false positives. Primary care physicians often do not appropriately follow a positive test. Further educational efforts are needed in an attempt to improve practice and further reduce the morbidity and mortality from colorectal cancer.

Ultrasound-assisted direct percutaneous endoscopic jejunostomy (DPEJ) tube placement

Direct percutaneous endoscopic jejunostomy (DPEJ) is an effective method of enteral feeding. However, failure rates with this procedure remain high due to various technical problems. We describe a case where modifications in the technique and ultrasound guidance assisted in a difficult DPEJ placement. This technique has the potential to improve the success rate of this procedure in selected cases.

A survey of gastroenterologists' perceptions and practices related to Helicobacter pylori infection

OBJECTIVE

The aim of this study was to assess the current practice of gastroenterologists in the United States concerning Helicobacter pylori (H. pylori) infection.

METHODS

We mailed a structured questionnaire to 1000 gastroenterologists chosen at random from a national database. We asked about personal and practice demographics and practices relating to testing for, and treating, H. pylori infection.

RESULTS

A total of 922 questionnaires were delivered, from which we received 286 responses (31%). Respondents used many different tests for H. pylori infection, but only 10% each had used either the 13C- or 14C-urea breath test. Testing for H. pylori infection was usually for appropriate reasons, although 21% indicated that they might not treat a patient with a positive test result. Different multiple treatment regimens were used; the most frequent were combinations of a proton pump inhibitor, clarithromycin, and either amoxicillin or metronidazole. Estimates of the prevalence of antibiotic resistance were highly variable and often inaccurate. Most respondents would not check asymptomatic individuals for the infection; however, in the absence of symptoms, 38% would personally undergo testing and treatment if positive.

CONCLUSIONS

Gastroenterologists usually test for H. pylori infection in appropriate conditions, but may not always treat the infection based on a positive test result. Most use efficacious regimens to treat the infection although many have inaccurate information on resistance rates, which may adversely influence prescribing. Many would have testing and, if positive, treatment in the absence of symptoms or a specific diagnosis, but do not recommend this for their patients.

The effects on intragastric acidity of per-gastrostomy administration of an alkaline suspension of omeprazole

BACKGROUND

It may be difficult to administer proton pump inhibitors via gastrostomy. Previous studies have examined the effect of intact proton pump inhibitor granules in orange juice. This study examined the effect of an alkaline suspension of omeprazole (simplified omeprazole suspension (SOS)) on 24-h intragastric acidity.

METHODS

Six men with an established gastrostomy had a baseline 24-h intragastric pH study using methodology we have previously described. They then received 20 mg SOS o.d. for 7 days and had a repeat pH study at the end of this period. Four of the patients then received 20 mg SOS with 30 cc of liquid antacid (Mylanta) per gastrostomy o.d. for a further 7 days and then underwent a third pH study.

RESULTS

SOS raised mean pH from 2.2 to 4.1. Intragastric pH was above 3, 4 and 5 for 35, 28 and 17% of the 24-h period at baseline, respectively; corresponding values after SOS were 63, 51 and 39%, respectively. Addition of liquid antacid to SOS did not further increase its pH-controlling effect.

CONCLUSIONS

We found a statistically significant effect of o.d. SOS on intragastric pH when administered via gastrostomy. We found no additional benefit of administering SOS with liquid antacid.

Simplified lansoprazole suspension--a liquid formulation of lansoprazole--effectively suppresses intragastric acidity when administered through a gastrostomy

OBJECTIVE

Lansoprazole suppresses intragastric acidity when given as nonencapsulated intact granules. Because the administration of granules via small-bore tubes may still be problematic, we studied the effect of a liquid formulation of lansoprazole obtained by suspending the contents of a standard 30-mg capsule in 10 cc of 8.4% NaHCO3.

METHODS

Six men with an established gastrostomy had a baseline 24-h intragastric pH study. Through the gastrostomy, they then received 7 days of once-daily dosing with 30 mg lansoprazole as intact granules in orange juice. After a 7-day washout period, they then received 7 days of once-daily dosing with the liquid formulation. Intragastric pH monitoring was repeated after each dosing period.

RESULTS

Baseline mean intragastric pH was 1.8 +/- 0.5 (SD). This increased to 4.5 +/- 0.5 with lansoprazole granules in orange juice, and to 5.1 +/- 1.1 after the liquid formulation. At baseline, intragastric pH was >3, 4, and 5 for 19.5%, 12.7%, and 8.1%, respectively, of the 24-h recording period. Corresponding values after lansoprazole granules in orange juice were 77.5%, 67%, and 49.6% (p < 0.01 for each comparison with baseline). After the liquid formulation, the corresponding values were 84%, 77.9%, and 65.9% respectively (p < 0.01 for each comparison with baseline; p > 0.05 for each comparison with lansoprazole granules in orange juice).

CONCLUSIONS

A liquid formulation of lansoprazole suppressed intragastric acidity when given through a gastrostomy. The degree of suppression was comparable to that obtained with intact nonencapsulated granules in orange juice.

Prospective determination of distal colon findings in average-risk patients with proximal colon cancer

BACKGROUND

Recent guidelines indicate that colonoscopy and sigmoidoscopy are both acceptable options for screening average-risk patients for colorectal cancer. Retrospective studies have found that a majority of patients with cancer proximal to the splenic flexure have a normal screening flexible sigmoidoscopy.

METHODS

This was a multicenter, prospective description of colonoscopic findings and family history in consecutive patients with proximal colon cancer.

RESULTS

Among 116 prospectively identified average-risk patients with cancer proximal to the splenic flexure, 40 (34.5%) had neoplasia distal to the splenic flexure. The prevalence of patients with adenomas greater than or equal to 1 cm, with only one tubular adenoma less than 1 cm, and with only hyperplastic polyps were 16.4%, 8.6%, and 6.9%, respectively.

CONCLUSIONS

Most average-risk patients with cancer proximal to the splenic flexure will have a normal screening flexible sigmoidoscopy. These patients have an unexpectedly high prevalence of large distal adenomas, but the prevalence of both single small tubular adenomas and hyperplastic polyps alone is similar to that expected during screening of the general population. Clinicians and payers should continue to seek methods to improve the cost-effectiveness and availability of screening colonoscopy in average-risk persons.

Examination of tissue distribution of Helicobacter pylori within columnar-lined esophagus

H. pylori may colonize columnar-lined esophagus, although an etiologic role in esophageal adenocarcinoma is unproven. H. pylori can adhere to intestinal metaplasia in the stomach. This study was designed to examine if H. pylori adheres to specialized intestinal metaplasia in columnar-lined esophagus. Esophageal biopsies from patients with columnar-lined esophagus were reviewed. Patients with only gastric metaplasia were excluded. Sections with specialized intestinal metaplasia in at least one third of at least one gland were recut, stained using the Giemsa stain, and reexamined by two independent pathologists using strict criteria for adherence by H. pylori. The 209 esophageal biopsies with adequate specialized intestinal metaplasia from 58 patients were examined: H. pylori was only seen on gastric metaplasia in three patients-and never on specialized intestinal metaplasia. Within the esophagus, H. pylori adheres only to gastric metaplasia, which is not considered premalignant for esophageal adenocarcinoma.

The pharmacodynamics of lansoprazole administered via gastrostomy as intact, non-encapsulated granules

BACKGROUND

Because of its acid-labile nature, lansoprazole is usually administered as encapsulated enteric-coated granules. The gelatin capsule and acid-resistant coating of the granules have been considered essential for effective drug absorption and optimal bioavailability. Lansoprazole may attain effective plasma levels when given as non-encapsulated intact granules, but effects on intragastric acidity are unknown.

AIM

To test the effectiveness of non-encapsulated. intact lansoprazole granules in suppressing intragastric acidity when administered through a gastrostomy.

METHODS

Eight men, each with an established gastrostomy, underwent baseline 24 h intragastric pH monitoring while off any acid-suppressing medication. Via the gastrostomy, they then received 7 days of once-daily dosing with 30 mg lansoprazole as intact granules in 3 fl. oz. of orange juice. Intragastric pH monitoring was repeated on day 7.

RESULTS

Mean intragastric pH pre-dosing was 1.96+/-0.5 (s.d.). This increased to 4.7+/-0.6 on day 7 (P < 0.0001). Median intragastric pH rose from 1.5 to 5.2 (P < 0.0001). Before lansoprazole, the proportions of time when intragastric pH was above 3, 4 and 5 were 23.2, 13.5 and 7.5%, respectively. Corresponding values after 7 days of lansoprazole were 81.1, 70.2 and 52.3% (P < 0.0001 for each comparison).

CONCLUSION

Lansoprazole can effectively suppress intragastric acidity when given through a gastrostomy as intact, non-encapsulated granules in orange juice.

Changing trends in esophageal cancer: a 15-year experience in a single center

OBJECTIVE

Esophageal adenocarcinoma is increasing in white men. We sought to identify trends in esophageal cancer in different patient groups in our region.

METHODS

We reviewed the records of all patients with esophageal cancer seen at two hospitals in Columbia, SC between 1981 and 1995. Patients were divided into three cohorts (1981-1985, 1986-1990, and 1991-1995). Demographic data, histological type, tumor stage, grade, and survival were recorded.

RESULTS

Histology was available in 371 of 386 patients (cohort 1, 113 patients; cohort 2, 144; and cohort 3, 114). Adenocarcinoma accounted for 24%, 27%, and 49% of esophageal cancer in white men in cohorts 1, 2, and 3, respectively (p = 0.03). Corresponding figures for African-Americans were 10%, 7%, and 3% (p = 0.22). Women comprised 8%, 14%, and 22% of patients with squamous carcinoma in the three cohorts (p = 0.03). Median survival for esophageal cancer was 6.0, 6.8, and 10.4 mo in cohorts 1, 2, and 3 (p = 0.0002).

CONCLUSION

Adenocarcinoma is increasing in whites. Squamous carcinoma remains the predominant type in this region, seen mainly in African-Americans. Esophageal squamous carcinoma is increasing in women. The mean age at diagnosis of squamous carcinoma has decreased in whites. There is a trend toward improved survival in patients with esophageal cancer.

Prospective, randomized, controlled comparison of the use of polyethylene glycol electrolyte lavage solution in four-liter versus two-liter volumes and pretreatment with either magnesium citrate or bisacodyl for colonoscopy preparation

BACKGROUND

Laxative pretreatment decreases the volume of polyethylene glycol electrolyte lavage solution (PEG-ELS) required for colonoscopy without compromising preparation quality. We compared the use of 4 L of PEG-ELS with the use of 2 L plus a laxative.

METHODS

One hundred fifty consecutive patients (148 men) undergoing outpatient colonoscopy were randomly selected for one of three preparations (Prep 1: 4 L PEG-ELS; Prep 2: 2 L PEG-ELS plus 296 mL magnesium citrate 1 hour prior; Prep 3: 2 L PEG-ELS plus bisacodyl 20 mg). Endoscopists were blinded as to the type of preparation.

RESULTS

Colonoscopy times were 37, 33, and 29.5 minutes (p = 0.02). Satisfaction scores (0 to 11) during preparation were 2.75, 1.84, and 2.54 (p = 0.05). Preparation times were 519, 397, and 379 minutes (p < 0.001). Preparation satisfaction scores (0 to 10) were 6.2, 7.7, and 7.4 (p < 0.001). Endoscopists' scores of preparation quality (1 to 10) were 7.3, 7.8, and 8.1 (p = 0.03). Volumes of liquid stool aspirated were 181, 103, and 90 mL (p < 0.001). Twenty-four patients receiving Prep 2 and 16 receiving Prep 3 had previous colonoscopy using full volume PEG-ELS; 88% who received Prep 2 and 56% who received Prep 3 preferred the newer preparation (p = 0.006).

CONCLUSIONS

Two liters of PEG-ELS plus laxative improved preparation quality and patient satisfaction and reduced preparation time. Magnesium citrate pretreatment had fewer symptoms and was preferred to bisacodyl. PEG-ELS in 2 L quantities could reduce costs, and consideration should be given to making it available commercially.

A study of the prevalence of Helicobacter pylori infection and other markers of upper gastrointestinal tract disease in patients with rosacea

OBJECTIVE

Recent reports have suggested that patients with rosacea, a chronic inflammatory skin disorder of unknown etiology, have an increased prevalence of Helicobacter pylori infection. However, no causal relation has been identified. This study was designed to determine the prevalence of H. pylori infection and upper gastrointestinal symptoms in rosacea patients and in subjects without chronic skin disorders.

METHODS

Forty-five patients with rosacea and 43 healthy subjects underwent serological testing for H. pylori infection. Demographics, gastrointestinal symptoms, and medication use were recorded using a structured questionnaire.

RESULTS

There was no significant difference in the seroprevalence of H. pylori infection between rosacea patients and healthy subjects (26.7% vs 34.9%; p = 0.40). Significantly more patients with rosacea complained of indigestion (66.7% vs 32.6%; p = 0.001) and used antacids (60% vs 32.6; p = 0.01). There was no significant difference in the prevalence of H. pylori infection between symptomatic and asymptomatic rosacea patients, or in those using antacids. There were no differences in the frequency of heartburn, history of peptic ulcer disease, family history of peptic ulcer disease, use of H2-receptor antagonists, or use of nonsteroidal antiinflammatory drugs.

CONCLUSIONS

Patients with rosacea have similar rates of H. pylori infection as healthy subjects. Rosacea patients complain significantly more frequently of "indigestion" and use more antacids unrelated to H. pylori infection.

Isoniazid-related hepatitis

Conclusive evidence of isoniazid (INH)-related hepatotoxicity ranging from asymptomatic elevation of liver enzymes to fulminant hepatic failure resulting in liver transplantation and/or death has been firmly established. Anticipation of the widespread usage of INH in the prevention and treatment of tuberculosis is expected due to the recent increasing incidence of tuberculosis. The aim of this article is to review the current concepts of pathogenesis, histopathology, risk factors and clinical features of INH-related hepatitis, emphasizing the need for vigilance.