Williams-Beuren syndrome: an update and review for the primary physician

Williams-Beuren syndrome is an autosomal dominant disorder resulting from a submicroscopic deletion of contiguous genes on the long arm of chromosome 7. It consists of a variety of hallmark physical features, which include distinctive facial characteristics, cardiac anomalies (of which the most common is supravalvular aortic stenosis), and occasional idiopathic hypercalcemia. The condition also includes a unique cognitive profile, with relative sparing of language and facial recognition skills against a background of mental retardation. This paper reviews the early history and clinical experience with this syndrome, how it unfolds from infancy through adulthood, and how it manifests in different organ systems. Evidence-based recommendations are then offered for the treatment of the specific developmental and medical issues that arise in patients with Williams syndrome.

Assessment of the factors involving in the development of hypothyroidism in HIV-infected patients: a case-control study

OBJECTIVES

Increased prevalence of thyroid dysfunction has been reported in HIV-infected patients, and recent studies have shown hypothyroidism as the most common thyroid function abnormality in this population, especially after treatment with antiretroviral drugs (HAART). The aim of this study is to assess risk factors of hypothyroidism in HIV-infected patients in Iran.

DESIGN

This case-control study was conducted among 15 hypothyroid (cases) and 70 euthyroid (control group) HIV-infected outpatients. Serum Free T4, Free T3, and TSH levels were measured, and data on age, sex, body mass index, opium addiction or injection of illicit drugs, duration of HIV infection and HAART, disease stage, CD4-cell count, opportunistic infection (OI) or malignancy, HCV co-infection, and drug use were collected.

RESULTS

We found no association between hypothyroidism in HIV-infected patients and any parameters measured, and P value was not significant for receipt of HAART (0.141), CD4-cell count (0.094), duration of HIV infection (0.474), duration of HAART (0.418), HCV co-infection (0.146), OI (0.566), or receipt of rifampin (0.816).

CONCLUSION

In this study, age, sex, HAART, mean CD4- cell count, duration of HIV infection, HCV co-infection, and OI were not significant risk factors of hypothyroidism in HIV-infected patients. The occurrence of hypothyroidism may be related to other factors or HIV infection itself. Therefore, hypothyroidism should be considered in all HIV-infected patients.

Long-term outcome of autologous transplantation of peripheral blood progenitor cells as postremission management of adult acute myelogenous leukemia in first complete remission

In order to improve leukemia-free survival (LFS) without the treatment-related morbidity of allogeneic bone marrow transplantation or multiple prolonged cycles of consolidation chemotherapy, we evaluated the long-term outcome of autologous transplantation of peripheral blood progenitor cells (PBPCs) as postremission therapy in 129 patients aged 18-71 years (median 49 years) with newly diagnosed acute myelogenous leukemia (AML) in first complete remission (CR1). The median follow-up from remission for surviving patients was 62.2 months (range 3.7-127.9 months). A total of 57 patients were alive and leukemia free at the end of the study. The LFS and overall survival 5 years from remission were 40.2% (+/-9.2%) and 41.4% (+/-9.4%), respectively. The median LFS and overall survival are 17.3 and 23.3 months, respectively. Multivariate analysis identified age as the most significant predictor for both LFS and overall survival. Karyotype was also found to be predictive of outcome. Our results show that autologous transplantation of PBPC procured after a single cycle of high-dose cytarabine-based consolidation chemotherapy for a population of adult patients with AML in CR1 produces a high likelihood of long-term LFS, offering a state of clinical minimal residual disease for the investigation of future therapeutic approaches.

Effective delayed neutron fraction and prompt neutron lifetime of Tehran research reactor mixed-core

In this work, kinetic parameters of Tehran research reactor (TRR) mixed cores have been calculated. The mixed core configurations are made by replacement of the low enriched uranium control fuel elements with highly enriched uranium control fuel elements in the reference core. The MTR_PC package, a nuclear reactor analysis tool, is used to perform the analysis. Simulations were carried out to compute effective delayed neutron fraction and prompt neutron lifetime. Calculation of kinetic parameters is necessary for reactivity and power excursion transient analysis. The results of this research show that effective delayed neutron fraction decreases and prompt neutron lifetime increases with the fuels burn-up. Also, by increasing the number of highly enriched uranium control fuel elements in the reference core, the prompt neutron lifetime increases, but effective delayed neutron fraction does not show any considerable change.

Diagnostic value of fecal calprotectin as a screening biomarker for gastrointestinal malignancies

BACKGROUND

Calprotectin in feces seems to be a more sensitive marker for gastrointestinal (GI) cancers than fecal occult blood, but its specificity may be too low for screening average risk populations. This study aims at evaluating the diagnostic value of fecal calprotectin as a screening biomarker for GI malignancies.

MATERIALS AND METHODS

In a case-control study, 100 patients with GI malignancies (50 patients with colorectal cancer and 50 patients with gastric cancer) and 50 controls were recruited in Tabriz Imam Reza and Sina hospitals during a 24-month period. One to two weeks after the last endoscopy/colonoscopy, fecal specimens were collected by the patients and examined by ELISA method for quantitative measurement of calprotectin content. The results were compared between the three groups.

RESULTS

The mean fecal calprotectin level was 109.1 ± 105.3 (2.3-454.3, median:74), 241.1 ± 205.2 (3.4-610.0, median:19.3) and 45.9 ± 55.1 μg/g (1.3-257.1, median:19.3) in gastric cancer, colorectal cancer and control group, respectively, the differences being significant (p<0.001) and remaining after adjustment for age. The optimal cut-off point for fecal calprotectin was ≥ 75.8 μg/g for distinguishing colorectal cancer from normal cases (sensitivity and specificity of 80% and 84%, respectively). This value was ≥ 41.9 μg/g for distinguishing gastric cancer from normal cases (sensitivity and specificity of 62%).

CONCLUSIONS

Our results revealed that fecal calprotectin might be a useful and non-invasive biomarker for distinguishing colorectal cancer from non-malignant GI conditions. However, due to low sensitivity and specificity, this biomarker may not help physicians distinguishing gastric cancer cases from healthy subjects.

Evaluation of different gridded rainfall datasets for rainfed wheat yield prediction in an arid environment

The accuracy of daily output of satellite and reanalysis data is quite crucial for crop yield prediction. This study has evaluated the performance of APHRODITE (Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation), PERSIANN (Rainfall Estimation from Remotely Sensed Information using Artificial Neural Networks), TRMM (Tropical Rainfall Measuring Mission), and AgMERRA (The Modern-Era Retrospective Analysis for Research and Applications) precipitation products to apply as input data for CSM-CERES-Wheat crop growth simulation model to predict rainfed wheat yield. Daily precipitation output from various sources for 7 years (2000-2007) was obtained and compared with corresponding ground-observed precipitation data for 16 ground stations across the northeast of Iran. Comparisons of ground-observed daily precipitation with corresponding data recorded by different sources of datasets showed a root mean square error (RMSE) of less than 3.5 for all data. AgMERRA and APHRODITE showed the highest correlation (0.68 and 0.87) and index of agreement (d) values (0.79 and 0.89) with ground-observed data. When daily precipitation data were aggregated over periods of 10 days, the RMSE values, r, and d values increased (30, 0.8, and 0.7) for AgMERRA, APHRODITE, PERSIANN, and TRMM precipitation data sources. The simulations of rainfed wheat leaf area index (LAI) and dry matter using various precipitation data, coupled with solar radiation and temperature data from observed ones, illustrated typical LAI and dry matter shape across all stations. The average values of LAI_max were 0.78, 0.77, 0.74, 0.70, and 0.69 using PERSIANN, AgMERRA, ground-observed precipitation data, APHRODITE, and TRMM. Rainfed wheat grain yield simulated by using AgMERRA and APHRODITE daily precipitation data was highly correlated (r² ≥ 70) with those simulated using observed precipitation data. Therefore, gridded data have high potential to be used to supply lack of data and gaps in ground-observed precipitation data.