Biomedical subjects

R Malekzadeh

Publications and source records attributed to R Malekzadeh.

At least 37 records · Page 2Linked to original sources

PubMed2004

High incidence of adenocarcinoma arising from the right side of the gastric cardia in NW Iran.

BACKGROUND: In the West, the subsite incidence of gastric cancer has changed in recent decades, with cancer of the cardia increasing in incidence and that of the more distal stomach decreasing. NW Iran has a very high incidence of upper gastrointestinal cancer and we have examined the anatomical site specific incidence in this geographical region. METHOD AND MATERIALS: Of 33 718 patients who visited our clinic from March 2000 to Jan 2003, 3119 (9.3%) with persistent upper gastrointestinal symptoms underwent upper gastrointestinal fibreoptic endoscopy. Exact tumour site, subsite, and axial view were determined. Demographic data including age, sex, and place of residence were assessed. Using matched data from the cancer registry and endoscopic survey, age standardised rates (ASR) for all subsites were calculated. RESULTS: Upper gastrointestinal cancer was diagnosed histologically in 499 patients (16.0%). The most frequent site was the gastric cardia (126 (25.3%)) followed by the oesophageal body (90 (18.0%)), antrum (82 (16.4%)), corpus (74 (14.8%)), distal oesophagus (57 (11.4%)), gastro-oesophageal junction (47 (9.4%)), and proximal oesophagus (22 (4.4%)). From axial views of the cardia, 51.4% and 6.8% of tumours were found to originate from the lesser and greater curve, respectively. ASR for gastric cancer were 51.2 in males and 15.4 in females. Cardia cancer with ASR of 26.4 in males and 8.6 in females was the major component of gastric cancer. CONCLUSION: NW Iran is a geographical region with a very high incidence of cardia cancer and with the great majority originating from the right side of the cardia. This suggests a locally acting luminal carcinogen. Studying the aetiology of this cancer in NW Iran is likely to increase our understanding of the rising incidence of this cancer throughout the Western world.

Adenocarcinoma↗

PubMed2004

Prevalence of gastric precancerous lesions in Ardabil, a high incidence province for gastric adenocarcinoma in the northwest of Iran.

BACKGROUND/AIMS: Ardabil Province, in northwestern Iran, has the highest rate of gastric (predominantly cardia) adenocarcinoma in Iran. This study aimed to investigate the feasibility of endoscopic screening and to look for associated Helicobacter pylori infection and gastric precancerous lesions. METHODS: One thousand one hundred and five adult volunteers, residents of Ardabil and Meshkinshahr, districts, 40 years old and above were selected and invited by a simple random household canvass in rural and urban locations. Informed consents were obtained and upper gastrointestinal video endoscopy was performed to biopsy all visible lesions and standard sites in the antrum, corpus, and cardia. RESULTS: One thousand and eleven of the invited individuals agreed to participate, including 494 men and 517 women, with a mean (SD) age of 53.32 (10.39) years. Endoscopy was well tolerated by all subjects; 96.7% of antral and 80.7% of cardia mucosal biopsies were satisfactory. The urease test or histology for H pylori was positive in at least 89.2% of subjects. Histological evidence of mucosal atrophy was seen in 39.3% of antral and 21.9% of cardia samples. Chronic gastritis with or without activity, reactive atypia of glandular epithelium, intestinal metaplasia, dysplasia, and cancer were found in 95.1%, 38.0%, 8.7%, 0.2%, and 0.3% of antral and 85.3%, 22.9%, 3.8%, 0.3%, and 0.1% of cardiac biopsies, respectively. CONCLUSION: Endoscopic screening for upper gastrointestinal diseases was feasible and well tolerated in Ardabil, Iran. Most subjects showed H pylori infection. Atrophic gastritis, reactive atypia, and intestinal metaplasia were common in antrum, corpus, and cardia subsites.

Adenocarcinoma↗

PubMed2003

Coeliac disease presenting with symptoms of irritable bowel syndrome.

BACKGROUND: Coeliac disease may easily mimic symptoms which are parts of the criteria used for diagnosing irritable bowel syndrome. AIM: To find the frequency of coeliac disease among patients diagnosed as irritable bowel syndrome. METHODS: During a period of one year, irritable bowel syndrome patients referred to a university clinic in Tehran were studied. For each patient, an asymptomatic sibling was enrolled as control. Serological tests for coeliac disease were performed in all patients and controls. If positive, duodenal biopsy was performed to confirm the diagnosis. Patients subsequently diagnosed as coeliac disease were placed on a gluten free diet and re-evaluated after 6 months. RESULTS: One hundred and five cases of irritable bowel syndrome and 105 controls were enrolled. Coeliac disease was diagnosed in 12 of the irritable bowel syndrome patients and none of the controls. Eleven coeliac disease patients adhered to a gluten free diet. After 6 months, all 11 patients had significant improvement in symptoms and three were totally asymptomatic. Six allowed repeated endoscopy after 6 months of gluten free diet, of which five showed improvement in histological findings. CONCLUSIONS: Coeliac disease is a common finding among patients labelled as irritable bowel syndrome. In this sub-group, a gluten free diet may lead to a significant improvement in symptoms. Routine testing for coeliac disease may be indicated in all patients being evaluated for irritable bowel syndrome.

Adult↗

PubMed2003

Tuberculous peritonitis in an endemic area.

BACKGROUND: Tuberculous peritonitis is a fatal disease if not diagnosed in time. AIMS: To identify the clinical, laboratory, and diagnostic features of tuberculous peritonitis in Iranian patients. PATIENTS: Included in the study were all cases of tuberculous peritonitis with a definite diagnosis confirmed by pathology in four referral University Hospitals in Tehran between 1989 and 1999. METHODS: All clinical, laboratory, and radiological findings as well as invasive procedures were reviewed. RESULTS: A total of 50 patients (30 female, 20 male), mean age 33.5 years were studied. Main presenting symptoms included abdominal pain (84%), weight loss (72%) and fever (50%). In 24% of patients a positive tuberculin test was found. Erythrocyte sedimentation rate >50 mm/h was detected in 60% of patients and 4.4% had an Erythrocyte sedimentation rate >100 mm/h. Laparoscopy or laparotomy showed peritoneal seeding in 74% of patients. CONCLUSIONS: Exudative ascites should give rise to clinical suspicion of tuberculous peritonitis in endemic areas or in immigrants from endemic areas. Laparoscopy is the most sensitive and specific diagnostic method.

Adolescent↗

PubMed2002

Endoscopic esophageal cancer survey in the western part of the Caspian Littoral.

After a hiatus of 30 years an attempt is now being made to re-assess the previously reported very high esophageal cancer incidence rates in the Caspian Littoral. The extraordinarily high incidence rates found in the eastern side of the Littoral, were re-confirmed five years ago for the Turkoman region, using esophageal balloon cytology supplemented by esophagoscopy of suspected cases. The focus this time was on the Ardabil province in the western side of the Caspian Littoral, where the rates reported 30 years ago were moderately high. A pilot chromoendoscopic screening program was scheduled for 650 asymptomatic adults from a randomly selected part of the city of Ardabil and adjoining villages, to evaluate the overall patterns of esophageal disease and to establish the utility of endoscopy as an esophageal cancer screening tool. 504 healthy volunteers, giving a compliance rate of 77.5%, submitted to esophagogastroscopy without any mishaps. Contrary to expectation, no dysplasia or esophageal cancer was found in 914 satisfactory biopsy specimens. Total absence of esophageal cancer or precursor dysplastic changes in the surveyed population in the western part of the Caspian Littoral was at variance with the cancer registry findings of three decades ago for the western part of the Littoral. A plausible explanation could be the improved socio-economic conditions and life style changes which have taken place in the recent past all along the Caspian Littoral, except in the Turkoman Plain.

Adult↗

PubMed2002

Effect of Helicobacter pylori eradication or of ranitidine plus metoclopramide on Helicobacter pylori-positive functional dyspepsia. A randomized, controlled follow-up study.

BACKGROUND: A definitive treatment for functional dyspepsia (FD), and the role of Helicobacter pylori eradication on the course of this disease are controversial. AIM: To investigate the effect of a combination of acid-suppressing and prokinetic drugs or eradication therapy on the course of H. pylori-positive FD. METHOD: A total of 157 patients with endoscopically-proven H. pylori-positive FD and no response to 4 weeks of antacid therapy were randomly divided into 2 groups. 84 were placed on bismuth subnitrate plus metronidazole and amoxicillin (group A) and 73 received ranitidine and metoclopramide for 4 weeks (group B). The severity of symptoms (7 items) were assessed on a 6-point categorical scale. Group B patients who failed to respond to their medication underwent eradication therapy after 3 months. All patients were followed and assessed for 9 months after the end of therapy by the same clinicians who initiated the therapy. RESULTS: At the end of the medication period, symptom's score decreased significantly, and to the same extent. At 3-month follow-up moderate or complete response was achieved in 27.4% (group A) and 19.2% (group B) by intention-to-treat analysis. 34 patients of group B, not responding to treatment, underwent eradication therapy and followed as group A. Eradication of H. pylori was successful in 60 of 110 controlled patients (54%). After 9-month follow-up, complete or moderate response was observed in only 30% of 60 patients in whom H. pylori had been eradicated (intention-to-treat analysis), compared to 38% in 50 noneradicated cases (p > 0.05, 95% CI: 19-43 vs. 24-52). CONCLUSION: Eradication therapy with bismuth compound is effective as ranitidine plus metoclopramide in a subgroup of patients with FD not responding to antacid therapy. There is no difference in improvement between patients cured or not cured from H. pylori infection. This suggests that bismuth compounds were effective in FD when used in the eradication regimen. Combination therapy with acid-suppressing drugs plus prokinetic and bismuth seems to hold promise for FD.

Adult↗

PubMed2001

Cyclosporin A is a promising alternative to corticosteroids in autoimmune hepatitis.

Autoimmune hepatitis (AIH), a chronic T-cell-mediated liver injury, is treated with corticosteroids with or without Azathioprine. Corticosteroids are not universally effective and have serious side effects. Cyclosporin A was effective in refractory cases. To assess efficacy and safety of Cyclosporin A (Neoral) in induction of remission in AIH patients this study was performed. Nineteen consenting AIH patients (nine treatment-naive) were treated with cyclosporin A in an open label trial and followed for 26 weeks. Liver biopsy was done and hepatitis activity index (HAI) determined at the beginning and end of treatment. Four patients did not complete the study for various reasons. Mean AST and ALT levels decreased from 948.7 +/- 103.5 and 454.8 +/- 354 to 100.6 +/- 111.8 and 78.5 +/- 40.3 (P < 0.03, P < 0.001) respectively. HAI decreased from 15.2 +/- 3.16 to 7.14 +/- 4.01 (P < 0.005). Serum creatinine did not change significantly. In conclusion, low-dose cyclosporin A appears to be safe and effective even in treatment-naive autoimmune hepatitis patients. Randomized controlled trials are warranted.

Adolescent↗

PubMed2001

Clarithromycin vs. furazolidone in quadruple therapy regimens for the treatment of Helicobacter pylori in a population with a high metronidazole resistance rate.

BACKGROUND: The eradication of Helicobacter pylori plays a pivotal role in the treatment of peptic ulcer disease. Metronidazole resistance, common in Iran, is claimed to be a major reason for the failure of metronidazole-containing regimens. Both clarithromycin and furazolidone are potential alternatives for metronidazole. AIM: To assess and compare the effectiveness of clarithromycin- and furazolidone-based regimens in eradicating H. pylori in a population with a high metronidazole resistance rate. METHODS: Patients with proven duodenal ulcer and H. pylori infection were randomly assigned to one of two groups. The patients received 2 weeks of omeprazole 20 mg b.d., amoxicillin 1000 mg b.d, bismuth subcitrate 240 mg b.d. and either clarithromycin 500 mg b.d. (the OABC group) or furazolidone 200 mg b.d. (the OABF group). RESULTS: A total of 118 patients were randomized, 55 in the OABC group and 63 in the OABF group. The intention-to-treat eradication rate was 84% and 85% for the OABF and OABC groups, respectively. The per protocol eradication rates were 90% for both groups. CONCLUSIONS: OABC and OABF are both effective in eradicating H. pylori in areas where metronidazole resistance is a problem. OABF is a good alternative in the face of growing resistance to clarithromycin in developed countries, and is attractive for developing countries where clarithromycin is not readily available.

Adult↗

PubMed2001

Randomized controlled trial comparing botulinum toxin injection to pneumatic dilatation for the treatment of achalasia.

BACKGROUND: Therapeutic options for achalasia include pharmacological therapy, surgical myotomy, pneumatic dilatation and intrasphincteric botulinum toxin injection. AIM: To compare botulinum toxin injection with pneumatic dilatation in a randomized trial. PATIENTS/METHODS: Forty adults with newly diagnosed achalasia were randomized to receive botulinum toxin (n=20) or pneumatic dilatation (n=20). Symptom scores were evaluated at 1, 6 and 12 months. Clinical relapse was defined as a symptom score greater than 50% of baseline. Relapsers received a second botulinum toxin injection or pneumatic dilatation. RESULTS: The cumulative 12-month remission rate was significantly higher after a single pneumatic dilatation (53%) compared to a single botulinum toxin injection (15%)(P < 0.01). The 12-month estimated adjusted hazard for relapse and need for retreatment for the botulinum toxin group was 2.69 times that of the pneumatic dilatation group (95% confidence interval; 1.18-6.14). When a second treatment was administered to the relapsers in each group, the cumulative remission rate 1 year after initial treatment was significantly higher in the pneumatic dilatation group (100%) compared to the botulinum toxin group (60%) (P < 0.01). There were no major complications in either group. CONCLUSIONS: Pneumatic dilatation is more efficacious than botulinum toxin in providing sustained symptomatic relief in patients with achalasia. The efficacy of a single pneumatic dilatation is similar to that of two botulinum toxin injections.

Botulinum Toxins↗

PubMed2001

A randomized controlled comparison of three quadruple therapy regimens in a population with low Helicobacter pylori eradication rates.

BACKGROUND AND AIM: We sought to compare the efficacy and tolerability of an omeprazole/clarithromycin/bismuth/tetracycline-based quadruple therapy to that of a ranitidine/metronidazole/bismuth/tetracycline-based quadruple therapy of 2 or 3 weeks duration in a population with a high prevalence of metronidazole-resistant Helicobacter pylori and low triple therapy eradication rates. METHODS: Two hundred and twenty-one patients who presented endoscopically proven duodenal ulcers and a positive rapid urease test were randomized to receive either: (i) omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d., bismuth subcitrate 240 mg b.i.d. and tetracycline 500 mg b.i.d (OCBT) for 2 weeks; (ii) ranitidine 300 mg b.i.d., metronidazole 500 mg b.i.d, bismuth subcitrate 240 mg b.i.d. and tetracycline 500 mg b.i.d. (RMBT2) for 2 weeks; or (iii) ranitidine 300 mg b.i.d., metronidazole 500 mg b.i.d, bismuth subcitrate 240 mg b.i.d. and tetracycline 500 mg b.i.d. (RMBT3) for 3 weeks. Patients were interviewed 2 weeks after the completion of therapy to review compliance and side-effects. Eradication of H. pylori was assessed 8 weeks after the completion of therapy with the use of a 14C-urea breath test. RESULTS: The per-protocol eradication rate was significantly higher with OCBT (88%) than RMBT2 (73%) or RMBT3 (71%) (P<0.05). The intent-to-treat eradication rate was numerically higher with OCBT (80%) than RMBT2 (68%) or RMBT3 (68%), although this difference did not reach statistical significance (P=0.09). Per-protocol or intent-to-treat eradication rates were similar with RMBT2 and RMBT3. There were significantly greater side-effects with the RMBT2 regimen. CONCLUSIONS: The omeprazole/clarithromycin/bismuth/tetracycline-based quadruple therapy provides higher H. pylori eradication rates than the ranitidine/metronidazole/bismuth/tetracycline-based quadruple therapy when administered per protocol. The prolongation of the latter regimen from 2 to 3 weeks did not increase eradication rates.

Adult↗

PubMed2001

Various durations of a standard regimen (amoxycillin, metronidazole, colloidal bismuth sub-citrate for 2 weeks or with additional ranitidine for 1 or 2 weeks) on eradication of Helicobacter pylori in Iranian peptic ulcer patients. A randomized controlled trial.

INTRODUCTION: One of the most economical and effective therapeutic regimens for eradication of Helicobacter pylori is the classic triple therapy with amoxycillin or tetracycline, metronidazole and a bismuth derivative. Addition of H2-receptor antagonists to these drugs may heighten the rate of eradication and shorten the duration. We therefore performed a randomized controlled trial comparing twice daily metronidazole, bismuth derivative and amoxycillin for 2 weeks with additional ranitidine for 1 or 2 weeks. PATIENTS AND METHODS: In total, 240 adult patients with duodenal ulcer and H. pylori infection were randomly assigned to one of the following regimens: (1) amoxycillin 1 g bid, metronidazole 500 mg bid, bismuth sub-citrate 240 mg bid and ranitidine 300 mg bid for 1 week; (2) triple therapy without ranitidine for 2 weeks; or (3) triple therapy plus ranitidine 300 mg bid for 2 weeks. Side-effects of the drugs were evaluated two weeks after starting the treatment. The rapid urease test and histology from antrum and corpus, and/or 14C- urea breath test were used to determine H. pylori eradication six weeks after starting the treatment. RESULTS: In total, 195 patients were followed up for 6 weeks. The most frequent drug side-effects were unpleasant taste (46%), dry mouth (41%) and fatigue (26%), which had an equal distribution in all treatment groups. Endoscopy and 14C- urea breath test were performed for 178 and 123 patients, respectively. Eradication of H. pylori was documented in 19/64 (29.7%), 29/63 (46%) and 50/68 (73.5%) of patients in groups 1, 2 and 3, respectively (P < 0.000001 for group 1 versus group 3; P < 0.0014 for group 2 versus group 3; difference not significant for group 1 versus group 2). An intention-to-treat analysis showed eradication rates of 19/80 (23.75%), 29/80 (36.25%) and 50/80 (62.5%) for groups 1, 2 and 3, respectively. At four weeks post-treatment, the most sensitive test for evaluation of eradication of H. pylori was histology. CONCLUSION: Although combined use of an H2-receptor antagonist and twice daily triple therapy in a two-week regimen is more effective than two-week triple or one-week quadruple therapy in Iranian patients, none of these regimens is ideal in countries with a probable high rate of resistant and strongly toxic strains of H. pylori.

Adult↗

PubMed2001

Second-line Helicobacter pylori eradication with a furazolidone-based regimen in patients who have failed a metronidazole-based regimen.

BACKGROUND/AIM: In developing countries the standard quadruple therapy containing metronidazole results in suboptimal eradication rates of Helicobacter pylori (<75%). In a retrospective study, we undertook to evaluate efficacy and tolerability of a furazolidone-based regimen (omeprazole, furazolidone, bismuth, and tetracycline) in patients who had previously failed the standard metronidazole-based regimen (omeprazole, metronidazole, bismuth, and amoxicillin). METHODS: The records of H. pylori infected patients who were referred to outpatient clinic (from March 1999 to August 1999) and who underwent previous eradication regimens were studied. A total of 320 cases were noted to have received a metronidazole-based quadruple regimen. From these 320 patients, 80 were noted to have failed this regimen based on a urea breath test. These 80 patients were enrolled in the study and given the furazolidone-based regimen. Side effects were assessed at follow-up visits. At least 2 months after the end of each therapy regimen, a (14)C-urea test was performed in each subject to document the cure of the patients. RESULTS: A total of 80 patients (39 males and 41 females) with a mean age of 43.8 +/- (SD) 13.3 years were studied. The H. pylori eradication rate was 90% with the furazolidone-based regimen. The side effects of this regimen were minor. CONCLUSIONS: A furazolidone-based regimen is effective in patients who do not achieve cure of H. pylori infection with the metronidazole-based quadruple therapy. In areas where the metronidazole resistance is high, initial therapy with a furazolidone-based regimen is recommended.

Adult↗

PubMed2000

Furazolidone versus metronidazole in quadruple therapy for eradication of Helicobacter pylori in duodenal ulcer disease.

OBJECTIVE: Furazolidone, an old but cheap antibiotic, was shown to be a good alternative to metronidazole in triple therapy for Helicobacter pylori eradication in areas where metronidazole resistant bacteria are common, but randomized studies are lacking. AIM: A randomized controlled trial to determine the efficacy and safety of furazolidone compared to metronidazole in classic quadruple therapy for eradication of H. pylori infection in duodenal ulcer patients. METHODS: Patients with endoscopically proven duodenal ulcer and positive urease test were randomized to receive ranitidine 300 mg, amoxycillin 1000 mg and bismuth subcitrate 240 mg b.d, with either furazolidone 200 mg b.d (RABF), or metronidazole 500 mg b.d. (RABM) for 2 weeks. Compliance and side-effects were monitored and recorded by table diary. H. pylori eradication was assessed at least 4 weeks after the completion of therapy with 14C-urea breath test. RESULTS: A total of 106 patients were enrolled and 101 (59 male, 42 female, mean age=40 +/- 11 years) completed the study. Endoscopic findings and demographic data were comparable in both groups. Intention-to-treat eradication rates were 75% and 55% (P=0.03) and per protocol eradication rates were 82 and 56% (P=0. 006) in the RABF and RABM groups, respectively. Side-effects were reported by 13 patients (27%) in the RABF group (one stopped treatment) compared to five patients (10%) in the RABM group (P=0. 04). CONCLUSION: Quadruple therapy containing furazolidone, instead of metronidazole, results in a significantly higher H. pylori eradication rate in Iranian duodenal ulcer patients.

Adult↗

PubMed1998

Continuous and more effective duodenal ulcer healing under therapy with bismuth and two antibiotics than with dual therapy comprising omeprazole and amoxicillin.

OBJECTIVE: To determine the speed of the healing process of duodenal ulcers during eradication regimens with and without a high-dose anti-secretory drug. SETTING: An outpatient department of a university hospital as a community-based and referral centre. MATERIALS: A total of 101 patients with proven duodenal ulcer and a positive urease test were randomized into two groups: one group received the classic triple therapy (bismuth subnitrate 3 x 375 mg for 4 weeks + tetracycline 3 x 500 mg + metronidazole 3 x 250 mg daily, both for 2 weeks ), the other group received dual therapy comprising amoxicillin 2 x 1000 mg + omeprazole 2 x 20 mg daily, both for 2 weeks. All patients underwent a control endoscopy 2 and 6 weeks after the beginning of treatment. Eradication was assumed if a urease test and culture were negative in all specimens taken from antral and corpus mucosa. RESULTS: In total, 93 patients completed all 6 weeks of the study (45 patients in the triple therapy group and 48 patients in the dual therapy group). The disappearance of ulcer pain was faster in the group under the regimen including omeprazole (dual therapy) than in the group with triple therapy (2.4+/-2.7 days versus 4.5+/-3.5 days; P< 0.01). The two-week healing rate was significantly higher in the patients treated with dual therapy than in the group treated with triple therapy (77% versus 33.3%; P< 0.01); however, 12 out of 37 patients with a healed ulcer in the dual therapy group had an ulcer relapse at 6 weeks (six became symptomatic). Only in one of these 12 patients was Helicobacter pylori eradicated. Fifteen of the 45 patients with triple therapy had healed ulcers at 2 weeks, and of these 14 remained healed at 6 weeks (H. pylori was eradicated in eight patients). The six-week healing rate with dual therapy was the same as with classic triple therapy (64.6% versus 77.6%); the eradication rate was lower in the former group than in the latter (30.4% versus 51.1% respectively; P=0.056). CONCLUSION: A high dose of a proton pump inhibitor (PPI) combined with amoxicillin results in rapid ulcer healing and pain disappearance, but is associated with early ulcer relapse due to lack of eradication of H. pylori. Its addition to regimens with bismuth and antibiotics is not necessary to achieve ulcer healing.

Adult↗

PubMed1998

Isolation of human osteoblast-like cells and in vitro amplification for tissue engineering.

As the field of dental implants continues to grow at a rapid rate so does our quest to find new techniques to enhance bone grafting. Tissue engineering is an exciting new technique in bone grafting. Therefore, the purposes of this study were to develop a simple, reproducible method to isolate human osteoblast-like cells (HOBs) and to evaluate in vitro cell proliferation within 2 different 3-dimensional (3-D) constructs targeted for tissue engineering applications. Ultimately, HOBs that have been amplified within 3-D constructs may be employed for bone regeneration techniques, such as onlay and sinus grafting prior to implant placement. Our cell isolation protocol employed human fetal calvaria tissue sequentially digested with trypsin and collagenase. The HOB cells from only the third and fourth digests were obtained, cultured and evaluated within the constructs. An osteoblast-like phenotype was in part verified for these HOB cells by demonstrating a significantly higher alkaline phosphatase activity than for human gingival fibroblasts, and a comparable level to the osteoblast cell line MG-63. The HOB cells were cultured within either poly (D,L-lactide) (PLA) or a fused fiber ceramic and evaluated for the ability to support in vitro HOB amplification. HOB proliferation was validated by scanning electron microscopy, identifying cells throughout the 3-D constructs. Continuous cell viability was demonstrated for the duration of the 33-day evaluation period and the extent of cell amplification reached approximately 20 times the seeding density. The in vitro amplification results further indicate that tissue engineering strategies with either the PLA or fused fiber construct may be suitable for bone regeneration therapy for dental implants.

Biomedical Engineering↗

PubMed1991

Ten versus 28 days of cimetidine treatment for duodenal ulcer in Iran. Evidence for the need for risk-oriented individual treatment of ulcer patients.

A clinical trial involving 100 duodenal ulcer patients was performed at the Shiraz Medical School in Iran, in which the known risk factors that influence the healing of duodenal ulcers in West Germany were examined. The patients were randomly allocated to groups receiving 2 x 400 mg cimetidine daily for 10 days (group I) or 28 days (group II). In addition, antacid was taken if pain occurred. Probable prognostic risk factors were noted, such as: age, sex, duration of ulcer history, duration of the present ulcer relapse, smoking habit, nocturnal pain, radiation of pain to the back, history of ulcer bleeding and use of analgesics. The number of ulcers, ulcer size, ulcer depth, bulbar deformity and narrowing were determined endoscopically. Follow-up examinations were performed in 89 patients 4 weeks after the start of treatment. The ulcers were healed in 20 out of 43 patients in group I (46%), and in 29 out of 46 in group II (63%) (p = 0.11). Statistical analyses were performed in both group combined to investigate unfavorable factors for healing. Following univariate analysis the following factors were prognostically unfavorable: bulb deformity (p = 0.003), radiation of pain to the back before treatment (p = 0.045), number of cigarettes smoked per day (p = 0.046). The patients with non-healed ulcers had more days with pain during treatment (p = 0.045). Using logistic regression analysis, the following prognostic factors were significant: number of cigarettes smoked per day (p = 0.03), radiation of pain to the back (p = 0.036), and bulb deformity (p = 0.048).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Orientation of cobra alpha-toxin on the nicotinic acetylcholine receptor. Fluorescence studies.

Four flourescein isothiocyanate (FITC) derivatives of Naja naja siamemsis 3 neurotoxin (alpha-toxin), labeled at the epsilon-amino groups of Lys-23, Lys-35, Lys-49, or Lys-69, and a tetramethylrhodamine isothiocyanate (TRITC) derivative, labeled at epsilon-amino group of Lys-23, were prepared and used to analyze the orientation of cobra alpha-toxin on the nicotinic acetylcholine receptor (AcChR) relative to both the plane of the membrane and the central ion channel. Fluorescence-quenching studies of the AcChR-bound FITC derivatives indicated significant solute accessibility to each site of labeling and suggested that none of the sites of FITC labeling is included in the binding surface of the alpha-toxin. Labeling of Lys-23 with TRITC did not affect the affinity of the alpha-toxin toward the AcChR and confirmed, contrary to some previous reports, a minimal role of Lys-23 in the binding surface of the alpha-toxin. Measurements of energy transfer between the lipid-membrane surface and the sites of labeling on receptor-bound alpha-toxin derivatives show that the relative distances of closest approach between the surface of the lipid membrane domain and the sites of labeling are in the order Lys-23 less than or equal to Lys-49 less than Lys-35 less than or equal to Lys-69. Energy transfer between AcChR tryptophans and the sites of labeling of bound derivatives was about 50% greater to Lys-49 than to Lys-23, Lys-35, or Lys-69, suggesting that Lys-49 is closer to receptor tryptophans and to the center of the extracellular domain of the receptor than Lys-23, Lys-35, or Lys-69. Combined with previous observations that the tip of the central loop of the alpha-toxin directly interacts with the AcChR, the above results suggest a model of the approximate orientation of the snake neurotoxins on the receptor. This model shows the tip of the central loop of the toxin directly interacting with the receptor surface and the major axis of the neurotoxin tilting from a perpendicular projection from the membrane. The surface of the alpha-toxin that includes Lys-23 projects away from the central ion channel and the surface that includes Lys-35 and Lys-69 faces the ion channel.

Amino Acid Sequence↗

PubMedDate not supplied

Endocrine cancer in Iran: based on cancer registry system.

BACKGROUND: A population-based registry of endocrine cancer cases in four Iranian provinces, was performed for the years 1996-2000. MATERIALS AND METHODS: Patients in each province were grouped according to age, gender and tumor specifics (site, morphology, behavior) and the data was coded according to the international classification of diseases for oncology. STATISTICAL ANALYSIS USED: Person-years of population at risk were calculated and the results were presented as incidence rates by sex, age, age specific rates and age standard rate (ASR) per 100,000 person-years, using direct method of standardization to the world population. RESULTS: A total of 319 cases of primary endocrine cancer were found and registered, including 313 cases of thyroid carcinoma and 6 cases of adrenal cancer. The thyroid carcinoma group cases consisted of papillary (82.7%), follicular (8.6%), medullary (7.0%) and anaplastic (1.6%) carcinomas. The ASR for thyroid carcinoma was 1.289 (0.627 for men, 1.59 for women), with the highest incidence rate in Kerman (ASR 1.643) and the lowest incidence rate in Golestan (ASR 0.735). For the 6 cases of adrenal cancer, 4 were neuroblastoma and 2 were pheochromocytoma. CONCLUSIONS: Iran was considered as an endemic, iodine-deficient area, until fairly recently. Iodinization of salt has been started about 12 years ago, in the nation. Considering the effect of improvement in the iodine intake in previously deficient communities, which is associated with an increase in the incidence of papillary carcinoma compared to other histologic types, the frequency and distribution of histologic types of thyroid carcinoma was closer to what can be seen in iodine-rich areas.

Adenocarcinoma, Follicular↗