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The impact of common cations and anions on the adsorption of uranium on rice straw activated carbon has been examined. The presence of these ions in solution was found to inhibit the uptake of cadmium by chitin to different degrees. Presence of Fe ions depressed the uranium removal to 77 and 20% at 20 and 100 mg/l, respectively. Coexistence of some anions induced small positive effect on uranium adsorption percent like Cl–; 91.0%, CO32- ; 89.3%, HCO-3 ; 88.8%, S2O2-3; 93.8%, and OH–; 91.6% compared to 84.2% uranium removal. Simultaneous presence of both uranium and thorium reduced uranium sorption from 100 to 35.9 mg/g. Data were good fitted by the Langmuir isotherm with correlation coefficient higher than 0.998. This means, the adsorption is monolayer chemical in nature on homogenous surface. [ABSTRACT FROM AUTHOR]

Nanocrystalline sensors having the general formula ZnO + x wt% CeO2, where x = 0, 2, 4 and 6 were prepared by chemical precipitation method and sintered at 400, 600 and 800 °C for 2h in static air atmosphere. The crystal structure and the morphology of the prepared samples were investigated and characterized by using XRD, IR, SEM and TEM techniques. The investigation revealed that the average crystallites size increases with increasing the sintering temperature. The electrical conductivity is found to increase with CeO2 additions and sintering temperature. Gas sensing properties of the prepared samples were also investigated. The effect of CeO2 content and sintering temperature on the structure, electrical conductivity and ethanol gas sensing properties of the prepared samples are discussed. [ABSTRACT FROM AUTHOR]

Date pits (DP) and sawdust (SD) were used as precursors for activated carbons which were prepared by steam pyrolysis of DP and chemical activation of SD, respectively. Surface characterization of both activated carbons was undertaken using the BET method. Adsorption of the radionuclides onto the activated carbon was studied as a function of shaking time, adsorbent mass and pH employing the batch technique. Such adsorption was strongly dependent on the pH of the aqueous medium in contact with the adsorbent, with the removal efficiency attaining a maximum at pH 6. The process was very fast initially, with maximum adsorption being attained within 180 min of initial contact. The adsorption rate could be best fitted by the pseudo-second-order kinetic model. The equilibrium data were analyzed using the Freundlich, Langmuir, Langmuir-Freundlich, Dubinin-Radushkevich, Temkin and Frumkin isotherms. The Langmuir-Freundlich and Frumkin equations were found to best represent the equilibrium data for both radionuclides. The isotherm model constants were determined and used to characterize the distribution of 60Co and 134Cs ions onto the adsorbent surfaces and to provide an insight into the affinity of the adsorbents towards these ions. [ABSTRACT FROM AUTHOR]

Trihalomethanes (THMs) are carcinogenic by-products of disinfection that are present in drinking water. In the present research, adsorption and photodegradation, either individually or in tandem, were employed for the removal of the principal THMs found in water supply systems. The effects of pH, contact time, adsorbents and adsorbate concentration on the adsorption system were investigated. The Langmuir and Freundlich adsorption isotherm models were used to analyze the resulting adsorption data. Photodegradation of THMs was carried out in the presence and absence of activated carbon. The integration of adsorption and photodegradation systems as a hybrid treatment process resulted in a synergetic enhancement of the THM removal efficiency. The kinetics of THM removal were found to follow the pseudo-second-order model rather than the Langmuir-Hinshelwood pseudo-first-order model. [ABSTRACT FROM AUTHOR]

The differences in the adsorption/desorption behavior of benzene, toluene, ethyl-benzene, and p-xylene (BTEX) using rice husk activated carbon (RHAC) were studied. It was proved that RHAC were quite effective in removing BTEX compounds from aqueous solutions. About 48 h was sufficient to attain maximum BTEX adsorption and desorption. Adsorption kinetics data proved a closer fit to the Weber-Morris model, while the isotherm experimental data were better fit to the Freundlich model, producing values of 1/n less than one, indicating favorable adsorption. Adsorption isotherms were determined in polluted surface water and it was found that the removal efficiency depends on the initial concentration of BTEX pollutants. Desorption equilibrium is less rapid than the adsorption equilibrium. BTEX adsorption/desorption was affected by chemical structure, solubility, and molecular weight. About 22% benzene, 33% toluene, 58% ethylbenzene, and 18.8% of p-xylene were released from RHAC after contact between the loaded matrix and reagent water. Sorption/desorption of p-xylene in RHAC was found to yield co-incident equilibrium isotherms and no significant hysteresis was observed. [ABSTRACT FROM AUTHOR]

Adsorption of three polycyclic aromatic hydrocarbons (PAH) in one mixture, namely naphthalene (NA), phenanthrene (PH), and pyrene (PY), was tested using various adsorbent materials: Bone charcoal (B-1 and B-2), Peat Moss (PM), Pyrolysis Residue (PR), Activated Rice Husk (RH), and powdered activated carbon (PAC). It was found that adsorption capacity RH carbon for PAH is comparable with the conventional adsorbent (PAC). Kinetics, equilibrium, and thermodynamic studies were carried out for the adsorption of selected PAH on RH carbon in single-component systems. Two days are sufficient contact time between each solute and the RH carbon. Intraparticle mechanism was proved for all compounds. Langmuir, BET, Freundlich, Redlick-Peterson, Toth, Generalized and Fritz-Schlünder isotherm equations were studied. It was found that the Freundlich isotherm for NA, Generalized isotherm for PH and BET isotherm for PY gave an excellent overall fit. The fitting was improved independent on the number of isotherm parameters. The calculated values of dimensionless separation factor RL of NA, PH, and PY were between 0 and 1 supporting the adsorption of PAH compounds onto RH carbon is very favorable. The results indicated the exothermic nature of PH adsorption onto RH carbon. Thermodynamic parameter was determined. Comparison with other studies was investigated. [ABSTRACT FROM AUTHOR]

Background: Dietary intake is widely known to play a crucial role in achieving peak bone mass among children and adolescents. Unfortunately, this information is lacking among Arab adolescents, an understudied demographic that has recently been observed to have a high prevalence of abnormal mineralization markers [low serum 25(OH)D, high serum alkaline phosphatase (ALP), low calcium (Ca) and/or inorganic phosphate (Pi)] suggestive of biochemical osteomalacia (OM, defined as any 2 of the 4 parameters). In order to fill this gap, we aimed to evaluate the associations of serum markers of biochemical OM with dietary intake of macronutrients, vitamins and trace minerals., Methods: Saudi adolescents ( N  = 2,938, 57.8% girls), aged 12-17 years from 60 different schools in Riyadh, Saudi Arabia were included. Dietary intake of nutrients was calculated following a semi-quantitative 24 h dietary recall over 3 weekdays and 1 weekend-day using a validated food frequency questionnaire. Compliance to reference daily intake (RDI) of macronutrients, vitamins and trace minerals were calculated. Fasting blood samples were collected and circulating levels of 25(OH)D, ALP, Ca, and Pi were analyzed., Results: A total of 1819 (1,083 girls and 736 boys) adolescents provided the dietary recall data. Biochemical OM was identified in 175 (9.6%) participants (13.5% in girls, 3.9% in boys, p  < 0.01) while the rest served as controls ( N  = 1,644). All participants had serum 25(OH)D levels <50 nmoL/L. Most participants had very low dietary intakes of Ca (median ~ 290 mg) and vitamin D (median ~ 4 μg) which are far below the RDI of 1,300 mg/day and 20 μg/day, respectively. In contrast, excess dietary intakes of Pi, Na, K, and Fe were observed in all participants. In the biochemical OM group, thiamine and protein intake were significant predictors of serum 25(OH)D, explaining 4.3% of the variance perceived ( r  = 0.23, adjusted r 2  = 4.3%, p  = 0.01). Among controls, dietary vitamin C and vitamin D explained 0.6% of the total variation in serum 25(OH)D ( r  = 0.09, adjusted r 2  = 0.6%, p  = 0.004)., Conclusion: Arab adolescents do not meet the RDI for dietary Ca and vitamin D, and none have sufficient vitamin D status (25(OH)D levels >50 nmol/L) but they exceed the RDI for dietary Pi. Interpreting these data in the light of the increased prevalence of rickets in Arab countries, food fortification to optimise vitamin D and Ca intake in Saudi adolescents should be considered., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Al-Daghri, Sabico, Wani, Hussain, Yakout, Aljohani, Uday and Högler.)

Nutrition-acquired osteomalacia is a bone mineralization disorder associated with dietary calcium and/or solar vitamin D deficiency, risk factors considered common in the Middle Eastern region. Establishing less invasive, cheap, and widely available diagnostic markers for this underdiagnosed entity is essential, in particular for screening in high-risk groups. This study assessed the prevalence of biochemical osteomalacia in Arab adolescents. In this cross-sectional study performed between September 2019 and March 2021, adolescents aged 12−17 years from 60 different secondary and preparatory year schools in Riyadh, Saudi Arabia were included. Anthropometrics and fasting blood samples were collected. Biochemical osteomalacia was defined as any two of the following four serum markers of hypomineralization, namely low 25 hydroxyvitamin D (25OHD < 30 nmol/L), high alkaline phosphatase (ALP), low calcium (Ca), and/or inorganic phosphorous (Pi). A total of 2938 Arab adolescents [1697 girls; mean age (years) 14.8 ± 1.8; 1241 boys; mean age 15.1 ± 1.6] were recruited. Vitamin D deficiency was noted in 56.2% (n = 953) of girls and 27.1% (n = 336) of boys (p < 0.001). The overall prevalence of biochemical osteomalacia was 10.0% (n = 295/2938) and was higher in girls than boys (14.7% vs. 3.6%, p < 0.001). The prevalence of low serum Ca and/or Pi was also higher in girls than in boys (24.2% vs. 12.5%, respectively, p < 0.001), as well as elevated ALP (5.1% vs. 1.5%, p < 0.001). Overall, girls were 4.6 times (95% CI 3.3−6.4) more likely to have biochemical osteomalacia than boys. Screening of apparently healthy Arab adolescents revealed a high prevalence of deranged mineralization markers suggestive of biochemical osteomalacia, which was significantly more common in girls than boys and was likely associated with Arab traditional clothing and diet. The proposed combination of typically altered mineralization markers for the diagnosis of osteomalacia is, at best, suggestive until further comparisons with established diagnostic tools (histological analysis of bone biopsies) are conducted.

Objectives: Type 2 diabetes mellitus (T2DM) outcomes were observed to be influenced by circulating trace elements' status. The differences and correlations between serum levels of chromium (Cr), manganese (Mn), nickel (Ni), and selenium (Se) in Saudi patients with and without T2DM as well as those with prediabetes (pre-DM) were examined in this retrospective cross-sectional study., Methods: Anthropometrics and fasting blood samples were collected from 119 patients with T2DM (aged 41-64 years), 95 non-T2DM (aged 27-55 years), and 80 with pre-DM (aged 35-57 years). An inductively coupled plasma-mass spectrometer was used to measure trace minerals in the blood., Results: T2DM patients had significantly lower Mn serum concentrations than controls. There was no difference in Cr and Ni levels between groups. Serum Mn and Ni levels were lower in pre-DM subjects than controls. Serum Se concentrations were higher in pre-DM and T2DM patients than controls. In T2DM patients, serum Cr and Mn levels were inversely correlated with glucose, while Ni and Se levels were positively correlated with glucose in the T2DM group., Conclusions: Because of their roles in glucose metabolism, impaired trace element status may also play a role in T2DM pathogenesis. Appropriate dietary control and mineral supplementation are recommended., Competing Interests: None., (AJTR Copyright © 2022.)

The present study aims to investigate the association of the serum levels of Fetuin-A and Fetuin-B with type 2 diabetes mellitus (T2DM) in obese Saudi patients and explore the mechanism that links obesity and T2DM in Saudi patients. In this study, a total of 240 adult Saudis (116 men and 124 women) in the age group of 42.7±11.6 years were divided into three groups based on fasting blood glucose (FBG) levels: controls, T2DM and prediabetic. The levels of FBG, lipid profile and serum insulin were measured. Enzyme-linked immunosorbent assay (ELISA) was done to measure Fetuin-A, Fetuin-B and C-reactive protein (CRP). The results show that participants of the prediabetic and T2DM groups had significantly higher body mass index (BMI) values and elevated blood pressure (BP), FBG, total cholesterol (TC), triglyceride (TG), insulin, homeostatic model assessment-IR (HOMA-IR) and homeostatic model assessment-β (HOMA-β) as compared to the control group (P<0.001). The T2DM group participants exhibited significantly higher BMI, BP, FBG, TG, insulin, HOMA-IR and HOMA-β as compared to the prediabetic group participants (P<0.001). The serum levels of high-density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C) were not significantly different among the three tested groups. The serum concentrations of CRP, Fetuin-A and Fetuin-B were slightly higher in T2DM patients as compared to the control group, but the difference failed to reach statistical significance (P>0.05). When results were segregated according to gender, FBG and HDL-C were significantly elevated (P=0.043 and P=0.002, respectively) in T2DM women (12.6±3.6 mmol/l and 1.0±0.3 mmol/l, respectively) compared to T2DM men (11.0±3.3 mmol/l and 0.86±0.2 mmol/l, respectively). However, the diastolic BP and waist-hip ratio (WHR) were significantly increased (P=0.010 and P=0.006, respectively) in T2DM men. The BMI and TC and all other measured parameters were similar between the two genders. Fetuin-A was significantly and positively associated with insulin levels (R=0.19, P=0.05), HOMA-IR (R=0.25, P=0.01) and TG (R=0.20, P=0.01) among overall participants of this study. The T2DM participants exhibited a significantly positive correlation with body weight. Fetuin-A was significantly and positively correlated with Fetuin-B in prediabetic participants, but this relation was not observed in the T2DM participants. Fetuin-B correlated inversely (P<005) with systolic BP (R=-0.20, P=0.01) and diastolic BP (R=-0.18, P=0.05). Interestingly, a strong inverse correlation was observed between Fetuin-B and TG in overall participants (R=-0.21, P=0.01) and specifically in T2DM women (R=-0.41, P=0.01). In conclusion, our study did not find a significant association of Fetuin-A or Fetuin-B levels in serum with T2DM. However, our results suggest that Fetuin-A may influence insulin resistance and serum Fetuin-B concentrations were inversely associated with TG in the general adult Saudi population., Competing Interests: None., (AJTR Copyright © 2022.)

Iron and vitamin D deficiencies are some of the most common health problems in the world. Iron is essential in oxygen transport and participates in many enzymatic systems in the body, with important roles in vitamin D metabolism. Osteoporosis is one of the most prevalent chronic disease of the elderly in the world as well as in the Saudi population. The relationship between iron, vitamin D deficiency and bone health comes from clinical observations in iron overload patients who suffered bone loss. The opposite scenario, whether iron and vitamin D deficiencies affect bone metabolism, has not been fully addressed. This is of great interest, as this nutrient deficiency is a worldwide public health problem and at the same time osteoporosis and bone alterations are highly prevalent. The relationship between 25(OH)D and iron deficiencies with osteoporosis is unknown up to date. This review presents the current knowledge on nutritional iron and vitamin D deficiencies in bone remodeling, and discuss the link between iron and bone metabolism among postmenopausal women. Finally, it is hypothesized that chronic iron and vitamin D deficiencies induces bone resorption and risk of osteoporosis, thus complete recovery from anemia and its prevention should be promoted in order to improve quality of life including bone health. Several mechanisms are implicated; hence, further investigation on the possible impact of iron and vitamin D deficiencies on the development of osteoporosis is needed., Competing Interests: None., (AJTR Copyright © 2022.)

The homeostasis of trace elements were observed to contribute to certain diabetic outcomes. This cross-sectional study determined the differences and associations between serum levels of copper (Cu), iron (Fe) and zinc (Zn) in Saudi patients with and without type 2 diabetes mellitus (T2DM) as well as those with prediabetes. Anthropometrics were measured, and fasting blood samples were collected from 119 patients with T2DM (aged 41-64 years), 95 non-T2DM (aged 27-55 years) and 80 with prediabetes (aged 35-57 years). Circulating trace minerals were determined using an inductively coupled plasma-mass spectrometer. Serum levels of Cu and Fe were significantly lower in T2DM than non-T2DM (adjusted p -values < 0.001). There was no difference in the Zn levels of the T2DM and non-T2DM groups. The serum Cu levels were significantly lower in the prediabetes group than the non-T2DM group ( p < 0.05). The serum levels of Cu, Fe and Zn were inversely associated with circulating glucose in the T2DM and prediabetes subjects ( p -values < 0.001). In conclusion, the differences in circulating trace elements were observed in Saudi subjects with varying glycemic statuses, suggesting an inverse association between T2DM progression and the decreasing serum Cu, Fe and Zn levels. Intervention trials are warranted to determine whether early correction of trace mineral deficiencies is beneficial in populations at higher risk for T2DM.

The study examined the associations between physical activity and appendicular lean mass (ALM), fat mass, and bone mineral density (BMD) and examined the role of physical activity on these variables. The participants included 497 men (age: 32.2 ± 10.4 years and body mass index: 28.2 ± 5.4 kg/m 2 ). The study was cross-sectional, and measurements included body composition measured on dual-energy X-ray absorptiometry and self-reported physical activity assessed using the International Physical Activity Questionnaire. Physical activity, including light physical activity, was associated with increased ALM ( P ≤ 0.05). Fat indicators, including waist circumference, were positively associated with ALM ( P ≤ 0.05), but not with BMD. Physical activity, including moderate-to-vigorous physical activity, was not associated with BMD, whereas ALM and handgrip strength were significantly associated with BMD ( P ≤ 0.05). Physical activity independent of exercise intensity was directly associated with ALM and indirectly associated with BMD through increased muscle mass and strength., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2019 Shaea Alkahtani et al.)

Objective: Subjects with low vitamin D levels are at risk of cardiometabolic disease. The aim of this study was to identify novel serological markers linking vitamin D status with cardiometabolic profile in non-diabetic adults with obesity., Methods: For the discovery phase, we used quantitative serum proteomics in sex-matched, age-matched and BMI-matched subjects with obesity [BMI: 25-35 kg/m 2 ] and low [25(OH)D < 50 nmol/L] vs. high vitamin D status [25(OH)D > 50 nmol/L] (n = 16). For the validation phase, we performed ELISA in a larger cohort with similar characteristics (n = 179)., Results: We identified 423 and 549 differentially expressed proteins in the high vs. low vitamin D groups of the male and female cohorts, respectively. The small molecule biochemistry protein networks and the glycolysis|gluconeogenesis pathway were significantly enriched in the DEPs of both sexes. As surrogate markers to these processes, the insulin-like growth factor binding protein -2  (IGFBP-2) was upregulated in males, whereas   IGFBP-3 was upregulated in females from the high Vitamin D status. This sex-specific trend  was confirmed using Luminex ELISA to an independent but clinically analogous cohort of males (n = 84, p = 0.002) and females (n = 95, p = 0.03)., Conclusions: The high Vitamin D status correlated with the serological upregulation of IGFBP-2 in males and IGFBP-3 in females with obesity and may constitute surrogate markers of risk reduction of cardiometabolic disease.

Background: The present randomized clinical trial characterized the beneficial effects of a multi-strain probiotics supplementation on improving circulating endotoxin levels (primary endpoint) and other cardiometabolic biomarkers (secondary endpoint) in patients with T2DM., Methods: A total of 78 adult Saudi T2DM patients (naïve and without co-morbidities) participated in this clinical trial and were randomized to receive twice daily placebo or probiotics [(2.5 × 10 9  cfu/g) containing the following bacterial strains: Bifidobacterium bifidum W23, Bifidobacterium lactis W52, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus casei W56, Lactobacillus salivarius W24, Lactococcus lactis W19 and Lactococcus lactis W58 (Ecologic ® Barrier)] in a double-blind manner for 12 weeks. Anthropometrics and cardiometabolic profiles were obtained at baseline and after 12/13 weeks of treatment., Results: After 12/13 weeks of intervention and using intention-to-treat analysis, no difference was noted in endotoxin levels between groups [Placebo - 9.5% vs. Probiotics - 52.2%; (CI - 0.05 to 0.36; p = 0.15)]. Compared with the placebo group however, participants in the probiotics groups had a significant but modest improvement in WHR [Placebo 0.0% vs. Probiotics 1.11%; (CI - 0.12 to - 0.01; p = 0.02)] as well as a clinically significant improvement in HOMA-IR [Placebo - 12.2% vs. Probiotics - 60.4%; (CI - 0.34 to - 0.01; p = 0.04)]., Conclusion: Using a multi-strain probiotic supplement daily for 12/13 weeks significantly improved HOMA-IR and modestly reduced abdominal adiposity among medication naïve T2DM patients., Trial Registration: ClinicalTrials.gov Identifier: NCT01765517 , Registered January 10, 2013.

Vitamin D binding protein (DBP) and albumin are the important determinants of circulatory 25(OH)D in adults. Physiological function of vitamin D is particularly regulated by DBPs. Serum parathyroid hormone (PTH) is considered as the biological activity reader of circulating 25(OH)D. We therefore examined the relationships between serum total, free, and bioavailable 25(OH)D versus PTH in apparently healthy Saudi female adults.A total of 350 apparently healthy Saudi female adults ([Mean ± standard deviation] age [years] 52.9 ± 9.2; body mass index [kg/m] 32.9 ± 5.4) were included in this observational study. Anthropometrics was measured as well as fasting glucose, lipid profile, calcium and phosphorous using routine methods. Serum 25(OH)D was measured using an electrochemiluminescence immunoassay. Serum DBP was determined by ELISA. Free and bioavailable 25(OH)D were calculated by comparing concentrations of total 25(OH)D, DBP, and albumin.Data revealed that circulating total 25(OH)D had weak but significant inverse association with DBP (R = -0.24; P < .01), and strong inverse associations with free 25(OH)D (R = -0.87; P < .001), albumin-bound 25(OH)D (R = -0.88; P < .001), and bioavailable 25(OH)D (R = -0.89; p < 0.001). None of the vitamin D metabolites, including 25(OH)D, correlated with serum PTH.Various metabolites of 25(OH)D are not correlated with serum PTH in Saudi adult females. Bioavailable, albumin-bound and free 25(OH)D cannot be surrogate measures for vitamin D status, at least in this population.

Postmenopausal osteoporosis is an important metabolic bone disease characterized by rapid bone loss occurring in the postmenopausal period. Recently, the most prevalent form of clinically significant osteopenia and osteoporosis involves various inflammatory conditions. The aim of the study is to evaluate the association between proinflammatory markers (interleukin [IL]-1β, IL-6, TNF-α) with bone turnover markers (BTMs) in postmenopausal Saudi women with and without osteoporosis. A total of 200 postmenopausal Saudi women ≥50 years old, 100 with osteoporosis and 100 without osteoporosis (control) were recruited under the supervision of qualified physicians in King Salman Hospital and King Fahd Medical City, Riyadh, Saudi Arabia. Serum tumor necrosis factor alpha (TNF-α), IL-1, IL-4, IL-6, and parathyroid hormone (PTH) were determined using Luminex xMAP technology. N-telopeptides of collagen type I (NTx) was assessed using ELISA, 25(OH) vitamin D and osteocalcin were determined using electrochemiluminescence, serum calcium and inorganic phosphate (Pi) were measured by a chemical analyzer. Serum IL-1β, IL-6, NTx, and PTH levels in women with osteoporosis were significantly higher than controls. Although IL-4 and osteocalcin were significantly lower than controls. IL-1β and TNF-α were positively associated with NTx in osteoporosis women. TNF-α, IL-6, and TNF-α were positively correlated with IL-lβ in both groups. A significant negative correlation between osteocalcin and IL-1β in healthy women and women with osteoporosis were observed. Findings of the present study implicate a role for cytokine pattern-mediated inflammation in patients with osteoporosis., Competing Interests: The authors have no conflicts of interest to disclose.