Risk Factors for Ischaemic Stroke in an Omani Community: A case-control study

Objectives

Stroke is recognised as the third most common cause of mortality and it has an increasing incidence in developing countries. Recognition and control of risk factors are of prime importance in the prevention of stroke. This study aimed to examine the characteristics of ischaemic stroke (IS) patients in Oman and quantify its various risk factors using a case-control model.

Methods

This case-control study was conducted from January 2012 to March 2013 at Sultan Qaboos University Hospital and Royal Hospital, Muscat. Adult Omani patients with IS who were admitted to either hospital were compared to age- and gender-matched controls. Demographic factors and frequency of various conventional risk factors were documented. Univariate and stepwise multivariate logistic regression analyses were performed to evaluate the risk factors associated with IS.

Results

A total of 255 patients and age-and gender-matched controls were included in this study. The mean age was 62.2 ± 13.2 years and 63.14% were male. Most cases (89.02%) were above 45 years of age. Cardio-embolism (31.76%) was the commonest mechanism of IS. Stepwise multiple logistic regression model revealed that family history of stroke was the strongest independent risk factor, followed by hypertension and high-density lipoprotein levels (odds ratio: 10.10, 5.17 and 3.34, respectively; P <0.01 each).

Conclusion

Cardio-embolism was the predominant mechanism of IS in this study. Family history of stroke, hypertension and reduced high-density lipoprotein were the leading independent risk factors. Strong emphasis on screening for risk factors, control of hypertension and lifestyle modification for those with a family history of stroke would be expected to emerge as the major stroke-preventive measures in Oman.

Aberrant CREB1 activation in prostate cancer disrupts normal prostate luminal cell differentiation

The molecular mechanisms of luminal cell differentiation are not understood well enough to determine how differentiation goes awry during oncogenesis. Using RNA-Seq analysis, we discovered that CREB1 plays a central role in maintaining new luminal cell survival and that oncogenesis dramatically changes the CREB1-induced transcriptome. CREB1 is active in luminal cells, but not basal cells. We identified ING4 and its E3 ligase, JFK, as CREB1 transcriptional targets in luminal cells. During luminal cell differentiation, transient induction of ING4 expression is followed by a peak in CREB1 activity, while JFK increases concomitantly with CREB1 activation. Transient expression of ING4 is required for luminal cell induction; however, failure to properly down-regulate ING4 leads to luminal cell death. Consequently, blocking CREB1 increased ING4 expression, suppressed JFK, and led to luminal cell death. Thus, CREB1 is responsible for the suppression of ING4 required for luminal cell survival and maintenance. Oncogenic transformation by suppressing PTEN resulted in constitutive activation of CREB1. However, the tumor cells could no longer fully differentiate into luminal cells, failed to express ING4, and displayed a unique CREB1 transcriptome. Blocking CREB1 in tumorigenic cells suppressed tumor growth in vivo, rescued ING4 expression, and restored luminal cell formation, but ultimately induced luminal cell death. IHC of primary prostate tumors demonstrated a strong correlation between loss of ING4 and loss of PTEN. This is the first study to define a molecular mechanism whereby oncogenic loss of PTEN, leading to aberrant CREB1 activation, suppresses ING4 expression causing disruption of luminal cell differentiation.

Epithelial Mesenchymal Transition (EMT) in Metastatic Breast Cancer in Omani Women

Breast cancer (BC) in Oman affects younger women and has a more aggressive course. Clinical and biological variables like age, pregnancy, tumor size, type, grade, receptor expression and proliferation predict disease aggression but there is no direct predictor of metastasis except lymphovascular invasion. Epithelial-mesenchymal transition (EMT) is characterized by epithelial cells losing epithelial and acquiring mesenchymal morpho-immunophenotypic characteristics. In tumors, EMT-like transitions may signify a metastatic phenotype and have features in common with cancer stem cells (CSC) which show resistance to chemotherapy. This study aimed to identify EMT and CSC phenotypes in metastatic and non-metastatic breast cancer in Omani women and their association with conventional clinico-pathological predictors of BC. In a retrospective study of ninety-six Omani women with breast cancer, the association of age, pregnancy/lactation, tumor size, type, grade, ductal carcinoma insitu (DCIS), lymphovascular invasion, hormone/ HER2 receptor expression and Ki67 proliferation index (Ki67 PI) was tested with EMT/ CSC phenotype and metastasis. Young age ≤ 40 years, lymphovascular invasion and EMT had a strong association with metastasis; CSC approached significance. Vimentin expression in tumor cells, fibronectin and MMP-11 in stroma were reliable markers of EMT; dual EMT and CSC phenotype (Vim+/ CD44+/ CD 24-/low) had a strong association with apocrine variant, basal-like tumors and triple negative cancers. EMT had a strong association with Ki67 proliferation index (PI) and CSC with HER2-like tumors and distant metastasis. These select markers may be useful in metastasis-prediction in pre-treatment biopsies.

Molecular Evidence of Helicobacter Pylori Infection in Prostate Tumors

OBJECTIVES

To determine whether Helicobacter pylori (H. pylori) is detectable in both benign prostatic hyperplasia (BPH) and prostate cancer (PCa). Epidemiological studies have shown significant associations between infective chronic prostatitis and prostatic carcinoma. Many bacteria have been found in the prostate of patients with chronic prostatitis, BPH, and PCa.

METHODS

One hundred consecutive patients with prostate diseases were enrolled in the study. Detection of H. pylori DNA in prostate tissue from patients with BPH and PCa was performed using both immunohistochemistry and PCR, and the results were confirmed by DNA sequencing. Odds ratios and the Fisher Exact test were used for the analysis of the associations between the variables.

RESULTS

Among the patients, 78% had BPH and 19% had PCa. While immunohistochemistry showed no positive sample for H. pylori, PCR combined with sequencing detected H. pylori DNA in prostate tissue samples from 5 patients. However, statistical analysis of the data showed that BPH and PCa are not significantly associated with the presence of H. pylori DNA in prostate tissue (odds ratio = 0.94, 95% confidence interval = 0.09-23.34, one-tailed Chi-square value = 0.660, p > 0.05). The limitation of this study was the small number of PCa patients.

CONCLUSIONS

This study provides, for the first time, molecular evidence of the presence of H. pylori DNA in prostatic tissue of patients with BPH and PCa. It paves the way for further comprehensive studies to examine the association of H. pylori infection with BPH and PCa.

Full Outline of UnResponsiveness score and Glasgow Coma Scale in medical patients with altered sensorium: interrater reliability and relation to outcome

PURPOSE

Full Outline of UnResponsiveness, or FOUR score (FS), is a recently described scoring system for evaluation of altered sensorium. This study examined interrater reliability for FS and Glasgow Coma Scale (GCS) among medical patients with altered mental status and compared outcome predictability of GCS, FS, and Sequential Organ Failure Assessment score.

PATIENTS AND METHODS

Adult patients with altered mental status due to medical causes were rated by neurology consultants and internal medicine residents on FS and GCS. Interobserver reliability for GCS and FS was assessed using κ score. Relation with outcomes was explored using univariate and multivariate analyses.

MAIN RESULTS

Of the 100 patients (age, 62 ± 17 years), 60 had neurologic conditions; 26, metabolic encephalopathy; 9, infections; and 7, others. Thirty-nine patients died at 3 months. κ Scores ranged from 0.71 to 0.85 for GCS and from 0.71 to 0.95 for FS. On multivariate analysis, GCS was predictive of outcome at 3 months; FS was predictive of mortality. Area under the receiver operating characteristic curves suggested equivalent performance of both scoring systems.

CONCLUSIONS

Interrater reliability and outcome predictability for FS were comparable with those for GCS. This study supports the use of FS for evaluation of altered mental status in the medical wards.

Insulin-like growth factor 1 gene polymorphism and breast cancer risk among arab omani women: a case-control study

Breast cancer is the most common cancer worldwide with significant global burden. Insulin-like growth factor 1 (IGF1) is an important regulator of cellular growth, differentiation, and apoptosis and mitogenic and antiapoptotic activities. Some studies suggested an association between cytosine adenine (CA) repeats gene polymorphisms of IGF1 and the risk of developing breast cancer while other studies did not find such an association. This study aims investigate the role of IGF1 (CA) repeats gene polymorphisms in the risk of developing breast cancer among Omani women.

METHODS

We analyzed (CA) repeats gene polymorphisms of IGF1 by extraction of genomic DNA from the peripheral blood of 147 patients with breast cancer and 134 control participants and performed genotyping using DNA sequencing.

RESULTS

Approximately 46% of patients carried the IGF (CA)(19) repeat allele, with 31.3% carrying two copies of this allele and 50% of controls carried the IGF (CA)(19) repeat allele with 30.1% carrying two copies of this allele. The difference of the IGF CA repeat groups was significant between cases and controls with (P =0.02). In contrast, there was no difference in the distribution of (CA)(19) repeat allele, (CA)(18) repeat allele and (CA)(19) repeat allele between cases and controls. The difference of the CA groups was significant between cases and controls among postmenopausal women with (P =0.026), whereas no difference was observed among postmenopausal subjects (P =0.429). In both pre- and postmenopausal groups there was no difference in the distribution of (CA)(19) repeat allele, (CA)(18) repeat allele and (CA)(20) repeat allele between patients and control subjects. On further IGF1 genotypes classification, we found an association between progesterone receptor status and the genotypes group where the non carrier of (CA)(19) repeat group was compared to (CA)(19) repeat carrier group (OR =2.482; 95% CI =1.119-5.503; P value =0.023).

CONCLUSION

Overall there was no association between the IGF (CA)(19) repeat and breast cancer in Omani females.

Protein Z levels in pregnant Omani women: correlation with pregnancy outcome

Placental insufficiency resulting in fetal loss has been recognized in women with thrombophilic predisposition. Recent studies indicate that there is a high prevalence of protein Z (PZ) deficiency in patients with unexplained fetal loss. The objective of this study was to measure the PZ levels in pregnant Omani women in the first, second and third trimesters and correlate with the pregnancy outcome. The study enrolled 126 consecutive pregnant women after an informed consent prospectively. PZ was estimated in the first, second and third trimester in 15, 97 and 66 pregnant women respectively and they were followed for pregnancy outcomes including live birth, still birth, spontaneous abortion/induced abortion, maternal complications, fetal complications and health risks/complications in the newborn. The median PZ level (Mean ± SD) in the first, second and third trimester were 0.98 (1.07 ± 0.46), 1.3 (1.36 ± 0.61) and 1.44 (1.43 ± 0.69) (P < 0.05, Student's t-test, between first vs. second and first vs. third trimester). PZ deficiency defined as PZ level below 0.54 μg/ml (below 10th centile in the Omani population) was observed in 4 (4.7%) women, but interestingly all had a normal pregnancy outcome. Amongst the 43 subjects in whom paired PZ estimations were available, reducing PZ levels were observed from baseline values in 8 (33%) with normal pregnancy outcome; 5 (55%), with diabetes; 3 (50%) with hypertension and 2 (50%) with low birth weight respectively (P < 0.05, chi square test). PZ values increased progressively during the three trimesters of pregnancy. However, this increase is blunted in patients with abnormal pregnancy outcome like low birth weight babies or pregnancies associated hypertension or diabetes. Isolated PZ deficiency alone did not result in an abnormal outcome in this cohort of subjects.

Consecutive exotropia after surgical treatment of childhood esotropia: a 40-year follow-up study

PURPOSE

To determine the incidence of consecutive exotropia (XT) following successful surgical correction of childhood esotropia (ET) and identify factors associated with its development.

MATERIAL AND METHODS

This is a retrospective study of 85 patients with ET, aged 2-24, who underwent strabismus surgery by a single surgeon between 1958 and 1969 in Sweden, until they were successfully aligned to ET within 10 prism dioptre, after primary or reoperation(s). The charts of these patients were reviewed, and data regarding age at onset of strabismus, surgery performed and outcome were recorded. The patients were recalled for a complete orthoptic examination in 2001-2003.

RESULTS

The incidence of consecutive XT in this cohort was 21% (18/85). Patients who had undergone multiple surgeries had a higher risk of developing consecutive XT compared to those successfully aligned with one surgery (p = 0.00036). Restriction of adduction and convergence postoperatively was associated with a high risk of consecutive XT (p = 0.0437). The incidence of consecutive XT did not vary with the level of visual acuity in the operated eye (p = 0.6428). Age of onset, age at surgery and amount of surgery did not appear to influence the risk for developing consecutive XT (p > 0.05).

CONCLUSION

This 40-year postoperative follow-up of patients with childhood ET who underwent strabismus surgery by a single surgeon in Sweden showed that multiple surgeries and presence of postoperative adduction deficit were the most important factors influencing the incidence of consecutive XT after surgery. Presence of uncorrected amblyopia did not alter the prognosis for long-term development of consecutive XT.

c-Abl and Arg are activated in human primary melanomas, promote melanoma cell invasion via distinct pathways, and drive metastatic progression

Despite 35 years of clinical trials, there is little improvement in 1-year survival rates for patients with metastatic melanoma, and the disease is essentially untreatable if not cured surgically. The paucity of chemotherapeutic agents that are effective for treating metastatic melanoma indicates a dire need to develop new therapies. Here, we found a previously unrecognized role for c-Abl and Arg in melanoma progression. We demonstrate that the kinase activities of c-Abl and Arg are elevated in primary melanomas (60%), in a subset of benign nevi (33%) and in some human melanoma cell lines. Using siRNA and pharmacological approaches, we show that c-Abl/Arg activation is functionally relevant because it is requiredfor melanoma cell proliferation, survival and invasion. Significantly, we identify the mechanism by which activated c-Abl promotes melanoma invasion by showing that it transcriptionally upregulates matrix metalloproteinase-1 (MMP-1), and using rescue approaches we demonstrate that c-Abl promotes invasion through a STAT3 → MMP-1 pathway. Additionally, we show that c-Abl and Arg are not merely redundant, as active Arg drives invasion in a STAT3-independent manner, and upregulates MMP-3 and MT1-MMP, in addition to MMP-1. Most importantly, c-Abl and Arg not only promote in vitro processes important for melanoma progression, but also promote metastasis in vivo, as inhibition of c-Abl/Arg kinase activity with the c-Abl/Arg inhibitor, nilotinib, dramatically inhibits metastasis in a mouse model. Taken together, these data identify c-Abl and Arg as critical, novel, drug targets in metastatic melanoma, and indicate that nilotinib may be useful in preventing metastasis in patients with melanomas harboring active c-Abl and Arg.

The Diagnostic Yield of Thyroid Function Tests and their Cost-effectiveness in the Student Clinic at Sultan Qaboos University: Retrospective chart review

OBJECTIVES

To assess the significance of requesting thyroid function tests (TFT) and their cost effectiveness for specific and non-specific symptoms of thyroid disease in a specific population in Oman.

METHODS

A retrospective chart review study was conducted in the student clinic at Sultan Qaboos University in Oman in the year 2007-2008. It included all patients (N = 319) of both sexes for whom TFTs were requested. The patients' main complaints and the final diagnoses were collected from their medical records.

RESULTS

The most common presentations for which TFTs were requested were irregular periods (n = 82); fatiguability (n = 49), palpitations (n = 39); weight changes (n = 22); hair changes (n= 20); sensation of heat and cold (n= 18); diarrhoea and constipation (n = 13), and neck swelling (n = 13). The most common diagnoses reached in relation to these complaints were polycystic ovarian syndrome (n = 51); iron deficiency anaemia (n = 42); anxiety and depression (n = 11); thyroid disease (n = 18), and no specific diagnosis (n = 193). The percentage of thyroid diseases among females (7.1%) compared to males (1.2%) was statistically significant (P <0.05). Thyroid disease accounted for 61.5% of those patient with neck swelling, 7.7% of those with palpitations, 4.1% of those with fatigue, 3% of those with other complaints, and 1.2% of those with irregular periods. The cost of the tests was around 20,000 US dollars.

CONCLUSION

TFT is necessary for those presenting with neck swelling, but restraint should be used in administering the test for those complaining of palpitations or fatigue. Additionally, irregular periods have little link with TFT abnormality.

The importance of HIV antenatal screening programs for pregnant women

OBJECTIVE

To investigate retrospectively the prevalence of human immunodeficiency virus (HIV)-1 and 2 among pregnant women during a 10-year period.

METHODS

The total number of pregnant women attending the Sultan Qaboos University Hospital (SQUH), Muscat, Oman between January 1995 and December 2005 was 11553 women. Their age range was 16-45 years (average of 28.67.6 years). The women were tested for HIV-1 and 2 using the standard enzyme-linked immunosorbent assay (ELISA). Positive samples were further tested by Western Blot. The data were statistically analyzed using the Statistical Package for Social Sciences Version 10.0.

RESULTS

By ELISA testing, 21 women were positive for HIV-1 (prevalence rate: 0.2%) and 3 women were weakly positive for HIV-1 (24 women; 0.2% prevalence rate). However, 15 women were confirmed HIV-1 positive using the Western Blot method (prevalence rate: 0.13%) with an average of 1.5 positive women per year. None of the women were found positive for HIV-2.

CONCLUSION

This relatively high prevalence of HIV-1 among pregnant women attending SQUH, highlights the need for screening all pregnant women attending different hospitals and antenatal clinics in Oman. This is essential for preventing the transmission of HIV-1 and 2 to the infants and to the community, and for the appropriate medical treatment and counseling of affected women.

Patients' views of interpersonal continuity of care in four primary health care centres of urban oman

OBJECTIVES

Interpersonal continuity of care (consulting the same physician) is widely regarded as a core value of primary care and a crucial component of quality of care. Nonetheless, interpersonal continuity as experienced by patients remains a neglected topic in Arab countries including Oman. The aim of this study was to explore how patients view interpersonal continuity of care in the primary care setting in Oman.

METHODS

Four primary health centres (PHCs) were selected from two urban cities in Oman. In the period June to August 2008, adult patients were surveyed by questionnaire at their PHC while waiting to see their primary care physicians (PCPs).

RESULTS

We interviewed 319 (71%) of enrolled participants. Their ages ranged from 18-70 years. The majority of patients (223 - 70%) thought interpersonal continuity was very important for them; 232 (73%) patients felt that they obtained better care with interpersonal continuity. 225 (71%) patients preferred interpersonal continuity if they had personal, family or social problems. Nonetheless, compared to male patients, female patients had less chance to maintain interpersonal continuity (p = 0.018). Interpersonal continuity increased as the number of consultations increased (p = 0.030). Preference for interpersonal continuity was associated with increasing age (p = 0.020) and with the presence of chronic illnesses (p = 0.001). Patients with chronic illnesses, who reported more preference for interpersonal continuity, were also found to be more compliant with medications and committed to carrying out recommended advice compared to patients without such illnesses (p = 0.027).

CONCLUSION

Omani patients perceived interpersonal continuity as an important aspect of primary care. Health planners should note patients' preference for interpersonal continuity and take visible measures to support it. A larger study is needed to survey more of the PHCs of Oman.

Visual rehabilitation by scleral fixation of posterior chamber intraocular lenses in Omani children with aphakia

BACKGROUND AND OBJECTIVE

To report indications and outcomes of scleral-fixated posterior chamber intraocular lenses (PC IOLs) in Omani children with aphakia.

PATIENTS AND METHODS

Patients with aphakia who were younger than 16 years, unsuitable for spectacle or contact lens correction, and without capsular support underwent an anterior vitrectomy and 10-0 polypropylene inside-out scleral fixation ofa PC IOL.

RESULTS

Scleral-fixated PC IOLs were implanted in 28 eyes of 24 patients. Group A comprised 10 (36%) eyes with congenital cataract and 3 (11%) eyes with ectopia lentis and group B comprised 15 (53%) eyes with traumatic cataract. The mean age at implantation was higher in group A (10.5 years) than in group B (7.3 years). Visual acuity improved in 17 of 28 (61%) eyes and remained at the preoperative levels in 11 of 28 (39%) eyes. Mean postoperative refraction was within +/- 2.0 diopters of the predicted refraction in 19 of 28 (68%) eyes. Complications included temporary intraocular pressure increase, vitreous hemorrhage, and iris capture with lens malposition.

CONCLUSION

Scleral-fixated PC IOLs are beneficial for children with aphakia without posterior capsular support who are lacking other means for visual rehabilitation. Patients with traumatic cataract and lens dislocation are more likely to experience an improvement in visual acuity postoperatively than patients with congenital cataract. However, this procedure is technically more difficult than routine PC IOL implantation and potentially carries greater risks.

Splenectomy for haematological disorders: a single center study in 150 patients from Oman

BACKGROUND

Haematological disorders, in particular sickle cell disease (SCD) and thalassaemia, are relatively common in Oman. We report our experience of splenectomy for haematological disorders and review the literature on splenectomy role in their management.

OBJECTIVES

To review our experience in the management of 150 patients with haematological disorders undergoing splenectomy with emphasis on indications and outcome. To compare our experience with those reported from outside this region.

METHODS

The records of 150 patients who underwent splenectomy over a thirteen year period were reviewed retrospectively, analyzing the age and sex of the patients, indication for splenectomy, operative procedures, complications, peri-operative management and outcome.

RESULTS

Of the 150 patients, 96 (64%) had SCD and 34 (22.6%) had beta-thalassaemia; the rest comprised patients with refractory idiopathic thrombocytopenic purpura (ITP) n=12, hereditary spherocytosis (HS) n=6, and auto-immune haemolytic anaemia (AHA) n=2. In SCD patients, the main indications for splenectomy were recurrent splenic sequestration (60.4%) and hypersplenism (36.4%), whereas in thalassaemic patients it was increased requirement of packed red blood cells (PRBC) transfusion (mean 310 ml, range 242-372 of PRBC/kg/year). All patients received prophylactic antibiotics and vaccination against pneumococcal infection and when the vaccine was available for Haemophilus influenzae. PRBC and platelet concentrates as well as intravenous fluids were infused preoperatively as per protocol. Concomitant procedures at laparotomy included liver biopsy (14.6%) and cholecystectomy (8.6%). The postoperative morbidity was low (8.6%) and there was no mortality. All patients were maintained on long term penicillin and proguanil, and the mean follow-up was 4.6 years. In SCD patients splenectomy eliminated the risks of life threatening acute splenic sequestration and improved significantly the blood counts of the hypersplenic cases, while in thalassaemic patients it reduced significantly the mean transfusion requirement by 100ml PRBC/kg/year (p<0.0001). Of the patients with refractory ITP, two thirds had a good response to splenectomy (p<0.0001). All HS and AHA patients benefited from splenectomy.

CONCLUSION

The predominant indications for splenectomy were recurrent acute splenic sequestration and hypersplenism in SCD patients, and increased transfusion demand in the thalassaemics. Overall, splenectomy proved beneficial in eliminating the risk of splenic sequestration in SCD patients, in improving the blood counts in SCD with hypersplenism and in reducing transfusion requirement in thalassaemic patients, while in ITP group two thirds of the patients benefited.

Epidemiological transition of some diseases in Oman: a situational analysis

During the past 35 years Oman has undergone a rapid socioeconomic and epidemiological transition leading to a steep reduction in child and adult mortality and morbidity due to the decline of various communicable diseases, including vaccine-preventable diseases. Good governance and planning, together with leadership and commitment by the government, has been a critical factor in this reduction. However, with increasing prosperity, lifestyle-related noncommunicable diseases have emerged as new health challenges to the country, with cardiovascular diseases, diabetes and obesity in the lead among other chronic conditions. Appropriate prevention strategies for reducing the burden of noncommunicable diseases are discussed.

Epidemiological transition of some diseases in Oman: a situational analysis

During the past 35 years Oman has undergone a rapid socioeconomic and epidemiological transition leading to a steep reduction in child and adult mortality and morbidity due to the decline of various communicable diseases, including vaccine-preventable diseases. Good governance and planning, together with leadership and commitment by the government, has been a critical factor in this reduction. However, with increasing prosperity, lifestyle-related noncommunicable diseases have emerged as new health challenges to the country, with cardiovascular diseases, diabetes and obesity in the lead among other chronic conditions. Appropriate prevention strategies for reducing the burden of noncommunicable diseases are discussed.

Sporadic colon cancer: mismatch repair immunohistochemistry and microsatellite instability in Omani subjects

BACKGROUND

Colorectal carcinoma (CRC) is the most common gastrointestinal malignancy in the world, and there are suggestions of a particularly high incidence in the Middle East, including those of African origin. Defects in DNA mismatch repair (MMR) systems are involved in the carcinogenesis of both sporadic and inherited human cancers. We assessed colonic cancers in an attempt to identify tumors with DNA MMR deficiency and microsatellite instability (MSI). Additionally, we tested the ability of cell cycle regulator p16 that effects cell proliferation and can be abrogated by hypermethylation of the promoter region.

METHODS

We reviewed the charts of 756 patients who were referred to the Oman major colonoscopy unit of the Sultan Qaboos University Hospital and Royal Hospital from the years 2000 to 2004. Colon cancer tissue was assayed using immunohistochemistry for expression of hMLH1 and hMSH2, and a panel of five pairs of microsatellite primers (NR21, NR22, NR24, BAT25, and BAT26) for MSI-H analysis and additional dinucleotide markers (D17S250, D5S346, and D2S123) used for MSI-L. The expression status of MMR genes and MSI was correlated with cancer stage, location, and histology. A total of 49 tumors were analyzed for histopathology, MSI, and hMLH1/hMSH2 protein expression analysis. The methylation status of the p16 promoter was determined by methylation-specific polymerase chain reaction (PCR).

RESULTS

The mean age for the carcinomas was 52.2 years and 53% of the patients were male. The majority of the tumors were left-sided. The information currently available indicates that there is an incidence of 4.7% colon cancer (49/1036) and 12.1% (126/1290) colon adenoma among the cases who underwent colonoscopy at these centers. The rate of MSI-H was 12.2% (n = 6), which appears to be the same as previously reported in literature. Eight of 49 tumors (16.3%) were MMR defective by IHC. Defects in the mismatch repair genes hMLH1 and hMSH2 were found in four (66.7%) and two (33.3%) of CRCs MSI-H cases, respectively. Defects in hMLH1 expression in tumors were commonly associated with moderate differentiation. The p16 promoter was methylated in 4% of tumors.

CONCLUSION

This is the first genetic study of CRC in this region of the world to demonstrate the incidence of MSI, p16 methylation, and hMLH1 and MSH2 expression in the Omani population. In addition, a relatively high frequency of CRC in younger age groups was noted, which is an important observation. The left-sided preponderance of MMR defective tumors was mostly associated with hMLH1, and with possible loss of hMSH2 expression, an observation that differs from studies on other populations. In conclusion, although the overall rate of CRC is unknown in this region, the frequency of MSI in CRC in this region appears to be the same as in Caucasians in the USA.

Arterial Switch Operation: Troponin T Does Not Predict Ventilation Requirements

The aim of this study was to assess whether postoperative cardiac troponin T levels could predict ventilation requirements in infants undergoing the arterial switch operation. Cardiac troponin T was measured 6 hours after aortic cross clamping and prior to tracheal extubation in 20 consecutive patients; 10 had simple and 10 had complex (with ventricular septal defect) transposition of the great arteries. The mean plasma troponin T level prior to extubation did not differ significantly in patients who were re-intubated and those who were successfully extubated. The initial cardiac troponin T levels in the complex defect group was significantly higher than in the simple transposition group. There was no correlation between initial cardiac troponin T levels and the duration of mechanical ventilation. There was no difference in mean duration of ventilation between the 2 groups. It was concluded that the postoperative cardiac troponin T level is not a predictor of successful extubation or prolonged artificial ventilation in this subset.

Knowledge and perceptions of diabetes in a semi-urban Omani population

Background

Diabetes mellitus is a major public health problem in the Sultanate of Oman. This study aimed to evaluate the knowledge and perception of diabetes in a sample of the Omani general population, and the associations between the elements of knowledge and perception, and socio-demographic factors.

Methods

The study was carried out in two semi-urban localities. A total of 563 adult residents were interviewed, using a questionnaire specifically designed for the present study. In addition to demographic information, the questionnaire contained questions on knowledge related to diabetes definition, symptoms, risk factors, complications and preventative measures, as well as risk perception for diabetes.

Results

Knowledge of diabetes was suboptimal. The percentages of correct responses to questions on diabetes definition, classical symptoms, and complications were 46.5%, 57.0%, and 55.1%, respectively. Only 29.5%, 20.8% and 16.9% identified obesity, physical inactivity and a positive family history, respectively, as risk factors for diabetes. A higher level of education, a higher household income, and the presence of a family history of diabetes were found to be positively associated with more knowledge.

Conclusion

This study demonstrated that there is lack of awareness of major risk factors for diabetes mellitus. Level of education is the most significant predictor of knowledge regarding risk factors, complications and the prevention of diabetes. Given that the prevalence of diabetes has increased drastically in Oman over the last decade, health promotion seems essential, along with other means to prevent and control this emerging health problem.

Measurement of circulating levels of VEGF-A, -C, and -D and their receptors, VEGFR-1 and -2 in gastric adenocarcinoma

AIM: To analyze the serum levels and prognostic significance of vascular endothelial growth factor (VEGF) -A, -C, and -D, and their receptors, VEGFR-1 and -2 in gastric adenocarcinomas.

METHODS: The serum levels of VEGF family members were measured in 76 control subjects and 76 patients with gastric adenocarcinoma using an enzyme-linked immunosorbent assay (ELISA). These measurements were correlated with clinco-pathological features and survival rates.

RESULTS: The serum levels of VEGF-A and its receptor, VEGFR-1, were significantly higher in patients with gastric cancer than in healthy donors (t = 2.3, P = 0.02 and t = 4.2, P < 0.0001, respectively). In contrast, the serum levels of VEGF-D were significantly higher in control subjects than in patients (t = 2.9, P = 0.004). There was no significant difference in serum levels of VEGF-C and VEGFR-2 between patients and controls. VEGF-C was associated with advanced tumor stage and presence of metastasis. VEGFR-1 was associated with metastasis, advanced overall stage, tumor differentiation and survival. VEGFR-2 levels were associated with poor tumor differentiation. There was no significant prognostic value for any of the VEGF family members or their receptors except for VEGFR-1 where high levels were associated with a poor overall survival.

CONCLUSION: Serum VEGF levels vary significantly in the same cohort of patients with variable clinico-pathological features and prognostic values. The simultaneous measurement of VEGF receptors levels in sera may overcome the limitations of a single biomarker assay.

Visual rehabilitation by scleral fixation of posterior chamber intraocular lenses in amblyopic aphakic children

Background/Aims:

To report on the outcome of scleral fixated posterior chamber intraocular lens (S-IOL) implantation in aphakic amblyopic children after 1 year.

Methods:

Amblyopic children with aphakia after traumatic and congenital cataract surgery unsuitable for spectacle or contact lens correction were operated with an anterior vitrectomy and inside-out double thread scleral fixation of an Alcon CZ70BD pcIOL. Refraction and vision was compared after 12 months.

Results:

From 2001-2006, 23 S-IOLs were implanted in 16 children (19 unilateral, 4 bilateral) aged 2-16 years: 10 eyes with traumatic [Group A], and 13 eyes with congenital cataracts including 3 eyes with ectopia lentis [Group B]. Preoperative UCVA compared to postoperative UCVA improved in 9/10 eyes in group A and 12/13 eyes in group B. Preoperative BCVA compared to postoperative UCVA improved in 9/10 eyes (90 percent) in group A and 4/13 eyes (31 percent) in group B. Mean age at surgery in group A was 6.8 years (1.5-16yrs) and in group B 10.5 years (4-16 years). More than one year elapsed in 2/10 eyes of group A and 8/13 eyes in group B. Postoperative refraction was within 2.0D of target in 17/23 eyes. Complications included temporary IOP rise in 2, vitreous hemorrhage in 1, and iris capture in 3 eyes. Two eyes required revision surgery.

Conclusion:

S-IOL implantation may be beneficial for aphakic children lacking other means for visual rehabilitation to improve vision. Amblyopia may be improved in most trauma, but only few congenital cataract eyes.

Outcome as a measure of quality of care in oncology: experience at sultan qaboos university hospital, oman

OBJECTIVES

Measurement of outcomes is increasingly employed as an indicator of the quality of clinical care. The most commonly measured outcome in many clinical studies, especially in oncology, still remains the overall survival rate. Sultan Qaboos University Hospital (SQUH), Oman, is striving for excellence through quality management. In seeking continual improvement, quality measurement exercises have been initiated throughout the Hospital. We present the overall survival rate of four of the ten most common cancers diagnosed in Oman.

METHODS

The cancers included non-Hodgkin's lymphoma (NHL), Hodgkin's lymphoma (HL), breast cancer, and stomach cancer. The studies were all retrospective and had been conducted previously. For present purposes, only the overall survival was compared with studies both from the region, and with bench-mark studies.

RESULTS

For NHL, with a median follow-up of 8 months, the 2-year overall survival rate was 64%; 90% for low risk, 55% for intermediate risk, and 15% for high risk groups. For HL, the 5-year overall survival rate was 64%; 76% for low risk and 42% for high risk. For breast cancer, the 5-year survival rate was 67%; percentages were 88%, 75% and 59% for Groups I, II, and III respectively. For gastric cancer, the 5-year survival rate was 16.5 %; 24% for the non-metastatic group.

CONCLUSION

The outcome of patients with early stages and fewer adverse prognostic factors is comparable to what has been reported in the international literature; however, the outcome is inferior for patients presenting with advanced stage disease and several adverse prognostic factors.

Some Risk Factors for Coronary Heart Disease among Omani Males: A matched case-control study

OBJECTIVES

Evaluation of some of the leading risk factors for coronary heart disease (CHD) among males in Oman.

METHODS

We conducted a hospital-based pair-wise matched case-control study among Omani CHD patients admitted in the Sultan Qaboos University Hospital and the Royal Hospital located in Muscat, Oman. The cases were matched with an equal number of controls in respect of age and hospital. The information was collected from the cases and controls based on an interview and review of the medical records of the admitted CHD patients. The odds ratios (ORs) were estimated under univariate as well as multivariate situations using conditional multiple binary logistic regression model.

RESULTS

The analysis revealed that 74 percent of the cases were of angina pectoris. The majority of the cases (96%) were above 40 years of age. The prevalence of sedentary life style was predominant (88.0%). Hypertension, diabetes, family history of CHD and a sedentary occupation were the most significant risk factors for the development of the disease. The estimated values of the adjusted ORs were found to be 9.98, 2.74, 28.19 and 3.00 respectively (p<0.05).

CONCLUSION

Individuals with hypertension, diabetes mellitus, a family history of CHD and with sedentary occupations are to be considered at high risk of developing CHD. Such individuals should be provided with appropriate health education along with close monitoring for symptoms and signs of CHD.

Reference ranges for lymphocyte subsets in healthy adult male Omanis

OBJECTIVE

To determine the reference ranges of lymphocyte subsets in serologically HIV-seronegative healthy male adults in Oman.

METHODS

A cohort, of 118 healthy male blood donors ranging in age from 18-51 years, was included in the study. The average age was 25 years. Blood samples collected into tubes containing ethylene-diamine-tetra acetic acid were investigated for lymphocyte subsets using flow cytometer. This study was conducted in the Immunology Laboratory of the Sultan Qaboos University, College of Medicine and Health Sciences, Muscat, Oman during the year 2006.

RESULTS

For the 118 males investigated, the mean percentage and absolute values of the lymphocyte subsets were as follows: CD3: 68.53 +/- 7.5%, 1701 +/- 489 cells/microliter; CD4: 40.4 +/- 6.5%, 1006 +/- 319 cells/microliter; CD8: 25.8 +/- 5.9%, 638 +/- 225 cells/microliter; CD19: 13.7 +/- 4.7%, 349 +/- 158 cells/microliter, and CD56: 12.2 +/- 6.7%, 308 +/- 204 cells/microliter. The ratio of CD4/CD8 was 1.6.

CONCLUSION

Immunophenotyping has been used to establish reference values of lymphocyte subsets in normal healthy adult males in Oman. The Omani male reference values obtained in this study show wide variations compared with kits values previously used as a reference.

Clinical and genetic study of spinal muscular atrophies in Oman

This article presents a retrospective study and a prospective study on spinal muscular atrophy in Oman. For the retrospective study, data were collected from neurophysiology records, from both inpatient and outpatient files. The prospective study was conducted on children as they presented to the hospital and was funded by Sultan Qaboos University. The patients of spinal muscular atrophy were classified into types I, II, and III based on their clinical features as per the International Spinal Muscular Atrophy Consortium classification. The incidence of spinal muscular atrophy was about 1 per 6000 live births. Spinal muscular atrophy type I formed 65% of the cases. Survival motor neuron deletion was seen in 70% of cases of all types of spinal muscular atrophy. The deletion was 83% in spinal muscular atrophy type I. A further study to look into the nondeletional cases is in progress.

NAT2 polymorphism in Omani gastric cancer patients-risk predisposition and clinicopathological associations

AIM: To study whether N-acetyltransferase 2 (NAT2) genotypes and phenotypes are associated with increased risk factor for gastric cancer in Omani patients and to study the clinico-pathological correlations and the prognostic significance of NAT2.

METHODS: Genomic DNA was extracted from peripheral blood of 100 gastric cancer patients and 100 control subjects. NAT2 genotyping was performed using DNA sequencing. The prognostic significance of NAT2 and other clinicopathological features was assessed by univariate and multivariate analyses.

RESULTS: We observed no significant association between NAT2 genotypes and phenotypes and gastric cancer risk. The NAT2 phenotype polymorphisms and gastric cancer risk predisposition were not modified by concomitant H pylori infection and smoking. There was no significant association between NAT2 and clinicopathological features, and NAT2 had no independent prognostic significance.

CONCLUSION: In the current study, NAT2 genotypes and phenotypes are not associated with gastric cancer risk predisposition. Moreover NAT2 phenotypes had no clinicopathological associations or prognostic significance.

[Conceiving and implementing an ISO 9001:2000 quality management system: quality improvement and efficiency increase over 3 years at the Dept. of Ophthalmology, Sultan Qaboos University in Oman]

BACKGROUND

Oman is a developing country of the Middle East with a University Hospital in a national health system. Problems related to documentation, structure, and procedure prevailing in a multicultural environment result in a lack of productivity. The aim of this study was to test the feasibility of introducing a quality management system according to ISO 9001:2000 into a university department of ophthalmology with special reference to quality and efficiency data over 3 years.

MATERIALS AND METHODS

Standardized types of documentation (35 documents, 183 forms and formats, and 453 registers) under a formal roof (booklets for work instructions, quality management, procedures) were conceived in 2001 and implemented, and were evaluated by descriptive statistics over the years 2002-2005 with respect to quality and efficiency. In 2005, the departmental QMS was merged into the QMS of the whole hospital.

RESULTS

Establishment of "responsibility clusters" with structured surveillance tasks, procedural improvements, and continuous audits resulted in a significant quality improvement already during the implementation until ISO 9001:2000 certification in 2002, and over the following 3 years. The data were assessed by non-conformities documented monthly (total inpatients: -50%, outpatients: -20%, operating theater: -100%, teaching: -10%; p <0.05) and increased efficiency assessed by the most important performance indicators (before QMS vs a median of 3 years with QMS): major surgery: +459%, inpatient stay: -49.7%, occupancy rate: +63.9%, technical diagnostics: +292.9%, postgraduate teaching total: +740%, research output total: +330% (p <0.05).

CONCLUSIONS

It is feasible to introduce the quality management system according to ISO 9001:2000 into a developing country in the Middle East. It has an immediate effect on the increase of efficiency (measured by performance indicators) and quality in all systems providing the possibility for regional benchmarking.

Perception of stroke and knowledge of potential risk factors among Omani patients at increased risk for stroke

Background

Previous studies have demonstrated poor knowledge of stroke among patients with established risk factors. This study aims to assess the baseline knowledge, among patients with increased risk for stroke in Oman, of warning symptoms of stroke, impending risk factors, treatment, and sources of information.

Methods

In April 2005, trained family practice residents at Sultan Qaboos University Hospital Clinics (cardiology, neurology, diabetic, and lipid clinics), using a standardised, structured, pre-tested questionnaire, conducted a survey of 400 Omani patients. These patients all demonstrated potential risk factors for stroke.

Results

Only 35% of the subjects stated that the brain is the organ affected by a stroke, 68% correctly identified at least one symptom/sign of a stroke, and 43% correctly identified at least one stroke risk factor. The majority (62%) did not believe they were at increased risk for stroke, and 98% had not been advised by their attending physician that their clinical conditions were risk factors for stroke. In the multivariable logistic regression analysis, lower age and higher levels of education were associated with better knowledge regarding the organ involved in stroke, stroke symptoms, and risk factors.

Conclusion

Because their knowledge about stroke risk factors was poor, the subjects in this study were largely unaware of their increased risk for stroke. Intensive health education is needed to improve awareness of stroke, especially among the most vulnerable groups.

The prognostic determinants of gastric cancer treatment outcome in Omani Arab patients

BACKGROUND

Gastric cancer is the most common cancer in Oman and a leading cause of cancer death. The variation in survival rates between countries and ethnic groups has been attributed to early detection policies, differences in clinicopathological features, treatment approaches, and biological characteristics. There were no previous reports on gastric cancer from Oman and very few studies on Asian Arabs.

AIM

To evaluate the impact of clinicopathological and treatment variables on the survival prospects of Omani Arab patients diagnosed with gastric cancer.

METHODS

The medical records of 339 Omani Arab patients diagnosed with invasive gastric adenocarcinoma during the period 1993-2004 were retrospectively reviewed. The relative importance of clinicopathological features and surgical and medical treatments were assessed using univariate and multivariate analyses.

RESULTS

Most patients had distal ulcerating-type gastric cancer and presented at advanced stages. The median survival time for the entire cohort was 12 months (95% CI 9.7-14.4) with a 5-year overall survival rate of 16.7%. On univariate analysis of 237 patients who underwent surgical resection, the following positive prognostic factors emerged as significant: early overall TNM stage, early T stage, negative lymph nodes, tumor size <5 cm, ulcerating macroscopic appearance, and curative surgical attempt. The independent prognostic factors on multivariate analysis were T stage and lymph node involvement.

CONCLUSION

The overall T and N stages are the most important determining factor for survival in Omani Arab patients. More efforts need to be made for the early detection of gastric cancer in developing countries such as Oman, while continuing to employ the standard surgical and medical treatments.

The prognostic significance of p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67 proteins expression in gastric cancer: a clinicopathological and immunohistochemical study of 121 Arab patients

BACKGROUND

The variability of prognosis within a pathological stage of gastric cancer (GC) at presentation, underscores the need for specific biological markers to identify subgroups of patients with aggressive course for intensive treatment. To our knowledge, this is the first study from an Arab population reporting on the relationship of p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67 expression, and clinicopathological features and their prognostic significance.

METHODS

Formalin-fixed paraffin-embedded tumors were studied by immunohistochemistry, using monoclonal antibodies to p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67. The results were correlated with clinicopathological features and survival.

RESULTS

M:F = 80:41; median age = 60 years; stage III and IV = 71%; and median follow-up = 34.4 months. Positive expression rates of p53, p27 kip1, p21 waf1, Ki67, and HER-2/neu were 54%, 40%, 8.3%, 70%, and 12% respectively. p53 expression correlated with age <60 years (P = 0.03), tumor size >5 cm (P = 0.01), p27 kip1 and Ki67 expression (P = 0.0001), and HER-2/neu (P = 0.04). p21 waf1 correlated inversely with T-stage (P = 0.008) and Her-2/neu expression correlated with histological grade (P = 0.04) and T-stage (P = 0.008). Univariate analysis showed that p53 overexpression (P = 0.01), fungating and infiltrative macroscopic appearance (P = 0.02), size >5 cm (P = 0.0001), lymph node metastasis (P = 0.0001), p T3 and T4 disease (P = 0.01), and overall stage III and IV (P = 0.0001) disease were adverse prognostic factors. Patients with tumor profiles p53 (-)/p27 (+) had better survival than those with p53 (+)/p27 kip1 (-)(P = 0.02). On multivariate analysis by Cox regression model, the expression of p53 (P = 0.03) and lymph node involvement (P = 0.01) were significant adverse prognostic factors for overall survival.

CONCLUSIONS

The expression of p53 in Arab patients with GC correlates with aggressive tumor characteristics and is an independent prognostic factor. The combined analysis of p53 and p27 kip1 is of added prognostic value.

Association of the risk allele of dopamine transporter gene (DAT1*10) in Omani male children with attention-deficit hyperactivity disorder

OBJECTIVES

To determine the frequency of the VNTR alleles in the human dopamine transporter gene (DAT1) in the Omani population and to investigate association of the VNTR alleles with attention-deficit hyperactivity disorder (ADHD).

DESIGN AND METHODS

92 Omani children with ADHD and 110 healthy Omani subjects were genotyped for the DAT1-VNTR polymorphism in a case-control study using two independent PCR tests (one developed in our laboratory) followed by agarose gel electrophoresis.

RESULTS AND CONCLUSIONS

We determined the DAT1-VNTR alleles in 202 Omani subjects. There were two common alleles (DAT1*9 and *10) and five rare ones. The DAT1*10 allele distribution was essentially the same both in the control (60.9%) and the patient group (64.6%). There was, however, a relatively higher occurrence of the DAT1*10 allele in ADHD males (69.4%) than females (55%), but this gender difference was not present in the control group (males 60%, females 62%).

The outcome of treatment of breast cancer in a developing country--Oman

The aim of the present study was to evaluate the outcome of treatment of breast cancer in Oman with an analysis of clinico-pathological features, treatment modalities utilized, and prognostic factors. One hundred fifty-two breast cancer patients diagnosed between January 1996 and June 2002 were evaluated retrospectively. Their mean age was 48.5 (S.D. +/- 10.8) years, and 48% of the female patients were premenopausal. The mean tumor size according to pathology was 4.6 (S.D. 3.29)cm, and 34.9% and 15.8% of patients had stage III or IV disease, respectively. Only 26.3% of the patients had breast-conserving surgery, and neoadjuvant chemotherapy was underutilized. The overall 5-year relapse-free survival (RFS) and overall (OS) survival rates were 62% and 64%, respectively. On multivariate analysis, axillary lymph node involvement and tumor differentiation were predictive of RFS and OS, respectively. Thus, breast cancer patients in Oman present with advanced stages of the disease at younger ages than their counterparts in the West and have lower survival rates. Increasing awareness and the introduction of screening programs and of a multidisciplinary approach are essential in Oman and other developing countries to improve the outcome of treatment.

Retinopathy of prematurity in VLBW and extreme LBW babies

OBJECTIVE

This is a hospital-based, prospective clinical study to determine the incidence, risk factors, and outcome of extreme low birth weight and very low birth weight pre-term babies with retinopathy of prematurity (ROP) at the Sultan Qaboos University Hospital, Oman.

METHODS

All babies with a birth weight =/< 1500 g and gestational age =/< 32 weeks admitted in the Neonatal Unit, were screened for ROP between 4 to 6 weeks of age and staged according to the international classification and were followed up until complete vascularization of the retina. Fifty nine babies formed the study group.

RESULTS

The overall incidence of ROP was 25.4% (15 out of 59), of which 6 babies had severe ROP and underwent cryotherapy/laser. All babies with ROP had a birth weight < 1250 g and were born before 31 weeks of gestation.

CONCLUSION

ROP is a multifactorial disease, the immature retina of the pre-term baby being the primary factor. Incidence and severity was inversely proportional to birth weight and gestational age. Multiple logistic regression analysis showed that sepsis and total parenteral nutrition to be highly significant risk factors. Repeated blood transfusions, hypotension and congenital heart disease with left to right shunt were seen to be considerably associated with the development of ROP. A decrease in overall incidence and severity of ROP was observed in this study.

MATERNAL RISK FACTORS AS DETERMINANTS OF LOW BIRTH WEIGHT AMONG ARMED FORCES FAMILIES

Low birth weight (LBW) is responsible for a significant proportion of child morbidity and mortality apart from its possible role in the occurrence of chronic disease in adult life. This study highlights the overall low incidence of LBWs at 13.6% among the Armed Forces families. The Other Ranks had a proportionally higher incidence of LBW at 24.14%. 82.14% of the LBWs occurred in the age group of 20-29 yrs, with only 6.93% of the births being teenage pregnancies. Primiparous women accounted for 54.95% of births but 75% of the LBWs. Smoking was not a significant factor. The findings underscore the need for special attention to other rank families and primiparas. A continued effort at updating the health care facilities provided to the Armed Forces families, and a concerted health and dietary advice by the authorised medical attendants, directed at the primiparous women, will further help lower the incidence of LBWs. The National LBW target of less than 10% by 2000 AD is definitely achievable by the Armed Forces.

Evaluation of some risk factors for ischaemic heart disease under a matched pairs case-control design

A pair-wise matched case-control study was carried out in 200 male patients of ischaemic heart disease (IHD). The cases were matched with an equal number of controls in respect of the variables viz., age and socio-economic status. The objective was to quantify the risk of developing IHD for some of the leading risk factors under the univariate and multivariate situations. The analysis revealed that of the factors (smoking, overweight, hypertension, diabetes, serum cholesterol and family history) considered, the smoking habit of the individual, presence of family history of the disease and overweight were the significant risk factors responsible for the development of the disease. The estimated odds ratios were found to be 3.29, 2.60 and 2.00 respectively.

Analysis of ordinal data in a study of endometrial cancer under a matched pairs case-control design

While estimating odds ratios (ORs) in the context of dose levels of conjugated oestrogen exposure and development of endometrial cancer, the categories formed by the levels of the exposure are ordinal in nature. In the literature, the binary logistic model is used for estimating OR for each category relative to the baseline category. We describe the use of two ordinal logistic models, the cumulative logit and continuation-ratio logit models, to estimate the ORs for the matched pairs case-control data set of the Los Angeles endometrial cancer study. A test for equality of the cumulative ORs across the exposure levels is proposed. The test statistic follows asymptotically the chi-square distribution.

Evaluation of susceptibility status of Culex quinquefasciatus larvae to few organophosphorus insecticides based on logistic regression analysis

A laboratory trial was carried out at Pune to evaluate the effectiveness of five types of larvicides viz. Malathion, Temephos, Fenthion, Dichlorvos and Fenitrothion against Culex quinquesfasciatus larvae. The expected number of mortality at various dose levels for the five types of insecticides were estimated separately using logistic regression model. Based on the fitted model, the estimated dose level corresponding to the 90 percent mortality (LC90) was obtained for each insecticide. Approximate 95 percent confidence intervals for the LC90 dose, in each case, has been provided. The analysis revealed that out of all the five types of insecticides included in the study, fenthion was the most effective. The estimated value of LC90 in this case was the lowest and is equal to 0.007 mg/L. The effectiveness of temephos, dichlorvos and fenitrothion was found to be approximately same and malathion was the least effective. The results were found to be comparable with that obtained under probit method.

Calcium channel blockers and the CVS reflex responses during lower body suction

Nine normal men (mean age 27.6 yr) were exposed to continuous lower-body suction pressure (LBSP) of -20 to -50 mmHg (for 5 min at each level) on four different occasions after having consumed a single oral therapeutic dose of either diltiazem, nifedipine, verapamil, or a placebo, randomly, in a single blind manner. The suction was applied at 12.30 pm in all experiments, while the medications were administered in such a manner so that their expected peak plasma levels would have been achieved at the time of suction application. The cardiovascular reflex effects commenced at a pressure of -30 mmHg, and peaked at -50 mmHg. The increases in the heart rate for all treatments at -50 mmHg was statistically similar (about 16-20 beats/min). The systolic BP fell by about 9 mmHg for the placebo experiments, and this change was not different from the changes produced by the 3 Calcium channel blocker treatments. The diastolic BP increase was about 3 mmHg. The Cardiac index did not vary significantly. Our results suggest that the commonly used Ca++ channel blockers do not adversely affect orthostatic tolerance.

Laboratory evaluation of some larvicidal agents against Anopheles culicifacies in Pune

A laboratory study to evaluate some larvicidal agents against Anopheles culcifacies was carried out. The findings of this study brought out that the larvae of this species were highly susceptible to temephos, fenthion, Paris green and Mosquito Larvicidal Oil (MLO) in that order. The LC50 values in respect of these larvicides were 0.0009 ppm, 0.0081 ppm, 0.029 ppm and 0.015 ml respectively and LC90 values were 0.0018 ppm, 0.022 ppm, 0.11 ppm and 0.046 ml respectively.

A case control study of cancer cervix patients attending Command Hospital, Pune

A case control study was undertaken with the objective to determine the association of certain host factors like marital status, age at first marriage, duration of married life, parity, literary status and genital hygiene, in the subsequent development of cancer cervix. A total number of ninety-two cases and an equal number of control subjects, under matched case control design, were studied at Command Hospital, Pune over a period of nine months. Salient findings of this epidemiological study have been highlighted in this communication. Few of the risk factors viz early age at first marriage, longer duration of married life, increased and early parity, low educational status and poor genital hygiene were found to have played significant role in the subsequent development of carcinoma cervix.

Medico-social profile of male teenager STD patients attending a clinic in Pune

A study of 250 male teenager STD cases was carried out to determine the association between certain medicosocial factors e.g. age, type of infection, educational status, source of infection, knowledge about mode of acquiring infection and prophylaxis etc. Salient findings of the study such as gonorrhoea being the commonest type of STD, curiosity being the main reason for first sexual exposure and prostitutes being the major source of infection have been highlighted in this communication.

A study of morbidity pattern among prostitutes attending a municipal clinic in Pune

The findings of the present study revealed that out of 200 prostitutes attending a clinic for various ailments, 81.50% were suffering from sexually transmitted diseases (STD) thus posing a potential risk of transmitting these diseases to their clients. Syphilis was found to be the commonest STD afflicting 36.80% of the respondents, the next common being the chancroid (31.28%); 5.52% of the respondents were found to be suffering from concomitant venereal infections. The other important communicable diseases with which some respondents were found to be afflicted, included--tinea infection (3 cases), scabies (2 cases), leprosy (2 cases), pulmonary tuberculosis (4 cases) and upper respiratory tract infection [3 cases). Thus, the prostitutes remain an undisputed potential source of infection not only of STDs but also several other communicable diseases. Therefore, their continuous surveillance, early diagnosis, appropriate treatment and subsequent follow-up should be meticulously carried out. On the other hand the public, particularly the sexually promiscuous individuals must be imparted vigorous health education to avoid exposure to this source.