Impact of dietary glycemic challenge on fuel partitioning.

The 'carbohydrate-insulin theory of obesity' is used to justify popular health claims stating that carbohydrates make you fat or a high glycemic load and consumption of sugar-sweetened beverages (SSBs) and breakfast skipping increase fat gain. According to this theory, the elevated postprandial insulin secretion to a high glycemic challenge is blamed as a causal mechanism by directing nutrients away from oxidation in muscle towards storage in adipose tissue. Scientific evidence is however largely disagreeing with an adverse effect of postprandial hyperinsulinemia on fuel partitioning. Possible reasons for this disagreement are differences in insulin sensitivity and energy balance. Diet-induced hyperinsulinemia may lead to a higher fat storage only at a positive energy balance. A shift in fuel partitioning towards fat storage requires improved or maintained insulin sensitivity in adipose tissue when compared with skeletal muscle. This may be the case during refeeding (after weight loss), physical inactivity or in metabolically healthy obese subjects (relative to insulin-resistant subjects). The adverse effect of a high-glycemic diet, SSBs consumption or breakfast skipping on body weight is likely due to increased energy consumption rather than to increased fat storage.

L shell X-ray fluorescence parameters of Pb in phthalocyanine complexes.

The L shell X-ray intensity ratios Li/Lα (i=l, ß and γ), the production cross-sections σ(Li) (i=l, α, ß and γ) and the L3 subshell fluorescence yields ω(L3) have been investigated for the element Pb in the phthalocyanine complexes. The measurements have been performed using an (241)Am annular radioactive source and an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The experimental values have been compared with the theoretical values of pure Pb element.

Knowledge, attitude and practice regarding breast cancer and breast self-examination among a sample of the educated population in Iraq

This cross-sectional, questionnaire-based study evaluated the knowledge, attitude and practice towards breast cancer and breast self-examination [BSE] among 387 [302 females and 85 males] educated Iraqis affiliated to 2 Iraqi universities. The participants were categorized into 3 occupations: student [71.3%], teaching staff [10.3%] and administrative staff [18.3%]. About half of the participants had a low knowledge score [< 50%]; only 14.3% were graded as [Good] and above. Almost 75% of the participants believed that the best way to control breast cancer was through early detection and other possible preventive measures. Most participants [90.9%] had heard of BSE, the main source of information being television. However, only 48.3% practised BSE; the most common reason for not doing so was lack of knowledge of how to perform the technique correctly. Almost 84% of the female participants were willing to instruct others in the technique of BSE

Breast cancer: demographic characteristics and clinico-pathological presentation of patients in Iraq

Breast cancer is the commonest type of malignancy in Iraq. The study was carried out on 721 out of a total of 5044 patients [14.3%] presenting with palpable breast lumps that were diagnosed as cancer. Approximately one third of the breast cancer patients were diagnosed at age 40-49 years; 71.9% came from urban areas; and 75% were married. History of lactation was reported in 63.1% and hormonal therapy in 29%. Positive family history was recorded in 16.2%. Although the lump was detected by the patient herself in 90.6% of cases, only 32% sought medical advice within the first month. Accordingly, 47% of these patients presented in advanced stages [III and IV]. The main histological type was invasive ductal carcinoma, in which pathological changes of grade II and III were observed in 56.6% and 39.9% respectively. DNA analysis showed that 80.3% of the carcinomas were aneuploid. The findings of this study justify increasing efforts for establishing comprehensive breast cancer control programmes in Iraq

Evaluation of limited sampling strategies for tacrolimus.

OBJECTIVE: In literature, a great diversity of limited sampling strategies (LSS) have been recommended for tacrolimus monitoring, however proper validation of these strategies to accurately predict the area under the time concentration curve (AUC0-12) is limited. The aim of this study was to determine whether these LSS might be useful for AUC prediction of other patient populations. METHODS: The LSS from literature studied were based on regression equations or on Bayesian fitting using MWPHARM 3.50 (Mediware, Groningen, the Netherlands). The performance was evaluated on 24 of these LSS in our population of 37 renal transplant patients with known AUCs. The results were also compared with the predictability of the regression equation based on the trough concentrations C0 and C12 of these 37 patients. Criterion was an absolute prediction error (APE) that differed less than 15% from the complete AUC0-12 calculated by the trapezoidal rule. RESULTS: Thirteen of the 18 (72%) LSS based on regression analysis were capable of predicting at least 90% of the 37 individual AUC0-12 within an APE of 15%. Additionally, all but three LSS examined gave a better prediction of the complete AUC0-12 in comparison with the trough concentrations C0 or C12 (mean 62%). All six LSS based on Bayesian fitting predicted <90% of the 37 complete AUC0-12 correctly (mean 67%). CONCLUSIONS: The present study indicated that implementation of LSS based on regression analysis could produce satisfactory predictions although careful evaluation is necessary.

Tacrolimus pharmacokinetics and pharmacogenetics: influence of adenosine triphosphate-binding cassette B1 (ABCB1) and cytochrome (CYP) 3A polymorphisms.

Tacrolimus, an immunosuppressant used after organ transplantation, has a narrow therapeutic range and its pharmacokinetic variability complicates its daily dose assessment. P-glycoprotein (P-gp), encoded by the adenosine triphosphate-binding cassette B1 (ABCB1) and the cytochrome (CYP) 3A4 and 3A5 enzymes appears to play a role in the tacrolimus metabolism. In the present study, two different renal transplant recipient groups were used to examine the influence of ABCB1 and CYP3A polymorphisms on the daily tacrolimus dose and several pharmacokinetic parameters. In total 63 Caucasian renal transplant recipients divided into 26 early [median (range) of the days since transplantation - 16 (3-74)] and 37 late [median (range) of the days since transplantation - 1465 (453-4128)] post-transplant recipients were genotyped for ABCB1 and CYP3A polymorphisms. The pharmacokinetic parameters of tacrolimus were determined for all renal transplant recipients and correlated with their corresponding genotypes. A significant difference in allele frequencies of the CYP3A4*1B (P = 0.028) and CYP3A5*1 (P = 0.022) alleles was observed between the early and late post-transplant recipient groups. Significantly higher dose-normalized trough levels (dnC(0)), dose-normalized area under the curve (dnAUC(0-12)), and dose-normalized maximum concentration (dnC(max)) were observed for carriers of the CYP3A5*3 variant allele in both renal transplant patient groups. Except for the daily tacrolimus dose (P = 0.025) no significant differences were observed for carriers of the CYP3A4*1B variant allele. Neither the individual ABCB1 polymorphisms nor the ABCB1 haplotypes were associated with any pharmacokinetic parameter. We noticed that patients carrying a CYP3A5*1 allele require a twofold higher tacrolimus dose compared with homozygous carriers of the CYP3A5*3 variant allele to maintain the target dnAUC(0-12). Therefore, genotyping for the CYP3A5*3 variant allele can contribute to a better and more individualized immunosuppressive therapy in transplant patients.

DNA proliferative index as a marker in Iraqi aneuploid mammary carcinoma

This study estimated nuclear DNA ploidy and DNA proliferative indices [PI] in mammary ductal carcinomas from 120 Iraqi female patients. Of the examined specimens, 82.7% were aneuploid. DNA ploidy correlated significantly with histological grade and estrogen receptor content of the primary neoplasm. In aneuploid carcinomas, high PI showed a clearer association than aneuploidy with menopausal status and progesterone receptor content of the tumour. PI and percentage aneuploidy were higher in larger tumours; nodal status showed no association with these cytometric findings. Using PI, patients classified as having Auer aneuploid carcinomas can be divided into subsets with different tumour characteristics, thus improving the selection of those whose high risk, node-negative presentation makes them candidates for adjuvant systemic therapy

Assessment of response to tamoxifen among Iraqi patients with advanced breast cancer

Eighty-eight women presenting with locally advanced or metastatic breast cancer were treated with tamoxifen alone. Estrogen and progesterone receptors [ER and PR] were immunocytochemically analysed in mammary tumour cells obtained by fine needle sampling from 73 patients. Of the breast carcinomas, 34.2% were ER+/PR+ and 43.8% were ER-/PR-. The ER+ content increased with age in postmenopausal women. After tamoxifen treatment objective remission occurred in 39.7% of the women. The overall response rate was 53.3% in the ER+/PR- group and 73.1% in the ER+/PR+ group. However, the response elicited in a case of the ER-/PR- phenotype justified the randomized use of tamoxifen among patients in Iraq where the necessary requirements for hormone receptor assessment are almost unavailable

Renal function following open heart surgery: the influence of postoperative artificial ventilation.

In order to detect changes in renal perfusion and function in the postoperative period of open heart surgery, a prospective study of 21 patients following open heart surgery was performed. Cardiac output, renal blood flow, glomerular filtration and renal function parameters were determined during intermittent positive pressure ventilation (IPPV), and during spontaneous ventilation (SV). During IPPV, renal perfusion was found to be substantially decreased. The glomerular filtration rate was also reduced, but to a lesser extent, implying that the changes were due to a selective increase in postglomerular vascular resistance. The clearances of urea and creatinine were decreased during IPPV, but the clearances of osmoles and potassium were higher. The reabsorption of sodium, potassium and osmoles were also decreased during IPPV, but not that of urea. These findings are consistent with the development of increased renal venous pressure during IPPV, caused by impeded venous return to the heart. In the low cardiac output range a cardiac index in excess of 0.5l/min/m2 during IPPV seems necessary to achieve the same renal perfusion as during SV.