Etiology and Clinical Presentation of Disorders of Sex Development in Kenyan Children and Adolescents

Objective. )e purpose of this study was to describe baseline data on etiological, clinical, laboratory, and management strategies in Kenyan children and adolescents with Disorders of Sex Development (DSD). Methods. )is retrospective study included patients diagnosed with DSD who presented at ages 0–19 years from January 2008 to December 2015 at the Kenyatta National (KNH) and Gertrude’s Children’s (GCH) Hospitals. After conducting a search in the data registry, a structured data collection sheet was used for collection of demographic and clinical data. Data analysis involved description of the frequency of occurrence of various variables, such as etiologic diagnoses and patient characteristics. Results. Data from the records of 71 children and adolescents were reviewed at KNH (n � 57, 80.3%) and GCH (n � 14, 19.7%). )e mean age at the time of diagnosis was 2.7 years with a median of 3 months. )irty-nine (54.9%) children had karyotype testing done. )e median age (IQR) of children with reported karyotypes and those without was 3.3 years (1.3–8.9) and 8.3 years (3.6–12.1), respectively (p � 0.021). Based on karyotype analysis, 19 (48.7%) of karyotyped children had 46,XY DSD and 18 (46.2%) had 46,XX DSD. )ere were two (5.1%) children with sex chromosome DSD. Among the 71 patients, the most common presumed causes of DSD were ovotesticular DSD (14.1%) and CAH (11.3%). Majority (95.7%) of the patients presented with symptoms of DSD at birth. )e most common presenting symptom was ambiguous genitalia, which

Effect of multiple micronutrient supplementation on survival of HIV-infected children in Uganda: a randomized, controlled trial

<p>Abstract</p> <p>Background</p> <p>Micronutrient deficiencies compromise the survival of HIV-infected children in low-income countries. We assessed the effect of multiple micronutrient supplementation on the mortality of HIV-infected children in Uganda.</p> <p>Methods</p> <p>In a randomized, controlled trial, 847 children aged one to five years and attending HIV clinics in Uganda were stratified by antiretroviral therapy (ART, n = 85 versus no ART, n = 762). The children were randomized to six months of either: twice the recommended dietary allowance of 14 micronutrients as the intervention arm (vitamins A, B₁, B₂, niacin, B₆, B₁₂, C, D and E, folate, zinc, copper, iodine and selenium); or the standard recommended dietary allowance of six multivitamins (vitamins A, D_2,B₁, B₂, C and niacin) as a comparative "standard-of-care" arm. Mortality was analyzed at 12 months of follow up using Kaplan Meier curves and the log rank test.</p> <p>Results</p> <p>Mortality at 12 months was 25 out of 426 (5.9%) children in the intervention arm and 28 out of 421 (6.7%) in the comparative arms: risk ratio 0.9 (95% CI 0.5 - 1.5). Two out of 85 (2.4%) children in the ART stratum died compared with 51 out of 762 (6.7%) in the non-ART stratum. Of those who died in the non-ART stratum, 25 of 383 (6.5%) were in the intervention arm and 26 of 379 (6.9%) in the comparative arm; risk ratio 1.0 (95% CI 0.6 - 1.6). There was no significant difference in survival at 12 months (p = 0.64, log rank test). In addition, there was no significant difference in mean weight-for-height at 12 months; 0.70 ± 1.43 (95% CI 0.52 - 0.88) for the intervention versus 0.59 ± 1.15 (95% CI 0.45 - 0.75) in the comparative arm. The mean CD4 cell count; 1024 ± 592 (95% CI 942 - 1107) versus 1060 ± 553 (95% CI 985 - 1136) was also similar between the two groups.</p> <p>Conclusions</p> <p>Twice the recommended dietary allowance of 14 micronutrients compared with a standard recommended dietary allowance of six multivitamins for six months was well tolerated, but it did not significantly alter mortality, growth or CD4 counts. Future intervention studies should carefully consider: (1) the composition and dosing of the supplements; and (2) the power needed to detect a difference between arms.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: NCT00122941</p

First principles calculations of the thermoelectric properties of

Oxide based thermoelectric materials have gained considerable interest due to their abundance, low toxic nature and high temperature stability. In the present work, we report the thermoelectric properties of α-MnO2 and β-MnO2 investigated using the Density Functional Theory with a Hubbard correction as implemented in the VASP code. Our calculated band gaps 0.27 eV and 1.28 eV for β-MnO2 and α-MnO2, respectively, are in excellent agreement with the experimental values and hence demonstrate the importance of including a Hubbard correction (U) in studying the physical and electronic properties of manganese oxides. The calculated elastic constants obey the Born Huang elastic stability criteria and therefore indicate that the studied materials are mechanically stable. The computed phonon band structures and the vibrational density of states do not have imaginary frequencies throughout the Brillouin zone and hence is a clear indication of the dynamic stability of these materials. Our calculated lattice thermal conductivities (κL) show a strong anisotropic behaviour along the a and c directions. At room temperature, the results show that acoustic phonon modes contribute ~56.0(55.8)% in α-MnO2 and ~80.4(73.8)% in β-MnO2 to the total κL along the a(c) directions respectively. In addition, the thermoelectric transport coefficients; σ and S2σ display an anisotropic behaviour between a and c directions. We obtained higher power factors, i.e., (447)(435) μW/m K2 for α-MnO2 and (134)(225) μW/m K2 for β-MnO2 with hole doping concentration of 1020 cm−3 along the a(c) directions respectively compared to that of Bi2Te3 (40 μW/K2cm) at 300 K. This large thermoelectric power suggests that these materials may be potential candidates for thermoelectric applications. However, our calculated dimensionless figure of merit for β-MnO2 and α-MnO2 are quite small due to large values of lattice thermal conductivities. Our highest computed ZT values are 0.02 for β-MnO2 with hole doping concentration of 1021 cm−3, and 0.14 for α-MnO2 with electron carrier concentration of 1021 cm−3 at 800 K along the c-direction

Theoretical investigation of the thermoelectric properties of ACuO

The electronic, structural, mechanical, lattice dynamics and the electronic transport properties of ACuO2(A = K, Rb and Cs) are investigated using density functional theory. The calculated elastic constants and their related elastic moduli, phonon spectra and electronic transport properties of these compounds are reported here for the first time. The predicted structural parameters are in excellent agreement with the available experimental data. The obtained lattice thermal conductivities, κL, of ACuO2 (A = K, Rb and Cs) are found to display strong anisotropic features along the a, b and c directions. It is also found that the average room-temperature κL of CsCuO2 is lower than those of RbCuO2 and KCuO2, which is due to its smaller group velocities in the low frequency region i.e., 0 ~ 3 THz. Our calculations also show that the acoustic phonon modes contribute considerably to the total κL along the a and b directions. The electrical conductivity (σ) and electronic thermal conductivity (κel) of ACuO2 (A = K, Rb and Cs) show anisotropic features i.e., σ and κel along the c-axis is significantly larger than along the a and b-axes. Meanwhile, our obtained Seebeck coefficient (S) values are found to be 248, 110 and 91 μV/K for p-doped KCuO2, p-doped RbCuO2 and p-doped CsCuO2 respectively at 300 K along the b-direction. These S values are found to be of the same order of magnitude with that of well known thermoelectric (TE) material, Bi2Te3 (with S of 200 μV/K at 300 K) and the recently discovered metal oxide TE material, NaCo2O4 (with S of 100 μV/K at 300 K). However, our computed figure of merit (ZT) values of ACuO2 (A = K, Rb and Cs) are found to be very small as compared to known thermoelectric materials. For instance, our highest computed ZT value is 0.11 for p-type KCuO2 along the c-direction at 750 K, 0.15 for p-type RbCuO2 and 0.25 for p-type CsCuO2 along the a-direction at 800 K. These small ZT values are caused by large values of the lattice thermal conductivities