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1.
Ann Saudi Med ; 42(5): 334-342, 2022.
Article in English | MEDLINE | ID: mdl-36252148

ABSTRACT

BACKGROUND: Prolactin is a hormone of the pituitary gland whose main function is the production of milk. Hyperprolactinemia is defined as an increase in prolactin levels above 25 µg/L in women and 20 µg/L in men. Causes of hyperprolactinemia include pituitary tumors, especially prolactinomas. Hyperprolactinemia can manifest clinically with a variety of symptoms, including galactorrhea and menstrual irregularities in women and erectile dysfunction in men. There are limited data on the epidemiology of hyperprolactinemia in the Middle East region. OBJECTIVES: Description of the epidemiology and clinical features of hyperprolactinemia in a cohort from Saudi Arabia. DESIGN: Medical record review SETTING: Tertiary medical center in Riyadh PATIENTS AND METHODS: The study included adult patients with hyperprolactinemia in King Abdulaziz Medical City in Riyadh. The patients were treated in endocrinology clinics from 2015 to 2019. Patients of both sexes older than 14 years were enrolled in the study. Patients with insufficient follow-up were excluded. Data were collected on demographic characteristics, symptoms, prolactin level, cause of high prolactin level, and treatment. MAIN OUTCOME MEASURES: The frequency of different etiologies and symptoms in patients with hyperprolactinemia. SAMPLE SIZE: 295 patients RESULTS: The majority of patients with hyperprolactinemia were female 256 (86.8%). Hyperprolactinemia was diagnosed more frequently in patients in the age groups 21-30 years (42.6%) and 31-40 years (24.1%). The majority of the study population was obese or overweight: 136 (46.3%) and 74 (25.2%), respectively. Most of the cases were symptomatic (192, 65.1%). In women, the most common symptom was oligomenorrhea (35%). In men, infertility and erectile dysfunction were the most common clinical symptoms (50% and 44.7%, respectively). Idiopathic causes were the most common etiology (108, 36.6%), followed by pituitary adenomas (81, 27.5%). The majority of patients were treated (184,62.4%), with cabergoline being the most commonly used medication (173, 94.0%). CONCLUSION: The demographic and clinical presentations and causes of hyperprolactinemia in male and female Saudi patients were similar to that in studies in other populations. LIMITATIONS: Single-center retrospective chart review study. CONFLICT OF INTEREST: None.


Subject(s)
Erectile Dysfunction , Hyperprolactinemia , Pituitary Neoplasms , Adult , Cabergoline/therapeutic use , Erectile Dysfunction/complications , Female , Humans , Hyperprolactinemia/drug therapy , Hyperprolactinemia/epidemiology , Hyperprolactinemia/etiology , Male , Pituitary Neoplasms/complications , Pituitary Neoplasms/epidemiology , Pregnancy , Prolactin/therapeutic use , Retrospective Studies , Saudi Arabia/epidemiology , Tertiary Care Centers , Young Adult
2.
J Colloid Interface Sci ; 610: 304-312, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-34922081

ABSTRACT

Metal-organic frameworks (MOFs) with exceptional features such as high structural diversity and surface area as well as controlled pore size has been considered a promising candidate for developing room temperature highly-sensitive gas sensors. In comparison, the hetero-metallic MOFs with redox-active open-metal sites and mixed metal nodes may create peculiar surface properties and synergetic effects for enhanced gas sensing performances. In this work, the Fe atoms in the Fe3 (Porous coordination network) PCN-250 MOFs are partially replaced by transition metal Co, Mn, and Zn through a facile hydrothermal approach, leading to the formation of hetero-metallic MOFs (Fe2IIIMII, M = Co, Mn, and Zn). While the PCN-250 framework is maintained, the morphological and electronic band structural properties are manipulated upon the partial metal replacement of Fe. More importantly, the room temperature NO2 sensing performances are significantly varied, in which Fe2Mn PCN-250 demonstrates the largest response magnitude for ppb-level NO2 gas compared to those of pure Fe3 PCN-250 and other hetero-metallic MOF structures mainly attributed to the highest binding energy of NO2 gas. This work demonstrates the strong potential of hetero-metallic MOFs with carefully engineered substituted metal clusters for power-saving and high-performance gas sensing applications.

3.
ACS Nano ; 15(3): 4045-4053, 2021 Mar 23.
Article in English | MEDLINE | ID: mdl-33496575

ABSTRACT

Ultrathin transparent conductive oxides (TCOs) are emerging candidates for next-generation transparent electronics. Indium oxide (In2O3) incorporated with post-transition-metal ions (e.g., Sn) has been widely studied due to their excellent optical transparency and electrical conductivity. However, their electron transport properties are deteriorated at the ultrathin two-dimensional (2D) morphology compared to that of intrinsic In2O3. Here, we explore the domain of transition-metal dopants in ultrathin In2O3 with the thicknesses down to the single-unit-cell limit, which is realized in a large area using a low-temperature liquid metal printing technique. Zn dopant is selected as a representative to incorporate into the In2O3 rhombohedral crystal framework, which results in the gradual transition of the host to quasimetallic. While the optical transmittance is maintained above 98%, an electron field-effect mobility of up to 87 cm2 V-1 s-1 and a considerable sub-kΩ-1 cm-1 ranged electrical conductivity are achieved when the Zn doping level is optimized, which are in a combination significantly improved compared to those of reported ultrathin TCOs. This work presents various opportunities for developing high-performance flexible transparent electronics based on emerging ultrathin TCO candidates.

4.
J Colloid Interface Sci ; 588: 305-314, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33412351

ABSTRACT

Metal-organic frameworks (MOFs) nanocomposites are under the limelight due to their unique electronic, optical, and surface properties for various applications. Plasmonic MOFs enabled by noble metal nanostructures are an emerging class of MOF nanocomposites with efficient solar light-harvesting capability. However, major concerns such as poor photostability, sophisticated synthesis processes, and high fabrication cost are raised. Here, we develop a novel plasmonic MOF nanocomposite consisting of the ultra-thin degenerately doped molybdenum oxide core and the flexible iron MOF (FeMOF) shell through a hydrothermal growth, featuring low cost, facile synthesis, and non-toxicity. More importantly, the incorporation of plasmonic oxides in the highly porous MOF structure enhances the visible light absorbability, demonstrating improved photobleaching performances of various azo and non-azo dyes compared to that of pure FeMOF without the incorporation of oxidative agents. Furthermore, the nanocomposite exhibits enhanced sensitivity and selectivity towards NO2 gas at room temperature, attributed to the electron-rich surface of plasmonic oxides. This work possibly broadens the exploration of plasmonic MOF nanocomposites for practical and efficient solar energy harvesting, environmental remediation, and environmental monitoring applications.

5.
Front Chem ; 8: 733, 2020.
Article in English | MEDLINE | ID: mdl-33005605

ABSTRACT

Phosphides of transition metals (TMPs) are a developing class of materials for hydrogen evolution reaction (HER) as an alternative to expensive noble metals to produce clean energy. Herein, the nitrogen-doped molybdenum oxide (MoOx) is developed via a facile and simple hydrothermal method, followed by annealing in the N2 atmosphere and phosphorization to form a nitrogen-doped oxygenated molybdenum phosphide (N-MoP) sphere-shaped structure. The developed N-doped phosphide structure depicts enhanced HER activity by reaching a current density of 10 mA cm-2 at a very low overpotential of only 87 mV, which is much better than annealed nitrogen-doped molybdenum oxide (A-MoOx) 138 mV in alkaline medium. N-MoP is a highly efficient electrocatalyst for HER attributed to a more exposed surface, large electrode/electrolyte interface and appropriate binding energies for reactants. This study extends the opportunity of developing nitrogen-doped TMPs, which can display exceptional properties as compared to their oxides.

6.
Chem Commun (Camb) ; 56(36): 4914-4917, 2020 May 05.
Article in English | MEDLINE | ID: mdl-32239030

ABSTRACT

The library of true two-dimensional materials is limited since many transition metal compounds are not stratified and can thus not be easily isolated as nanosheets. Here, micron-sized ultrathin rutile TiO2 nanosheets featuring uniform thickness (2 ± 0.5 nm) with dielectric constant (ε⊥ = 24) have been synthesized via a liquid metal synthesis strategy.

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