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Maternal exposure to alkali, alkali earth, transition and other metals: Concentrations and predictors of exposure

Hinwood AL, Stasinska A, Callan AC, Heyworth J, Ramalingam M, Boyce M, et al.

Environ Pollut, 2015 Sep;204:256-63.
PMID: 25984984 DOI: 10.1016/j.envpol.2015.04.024

Most studies of metals exposure focus on the heavy metals. There are many other metals (the transition, alkali and alkaline earth metals in particular) in common use in electronics, defense industries, emitted via combustion and which are naturally present in the environment, that have received limited attention in terms of human exposure. We analysed samples of whole blood (172), urine (173) and drinking water (172) for antimony, beryllium, bismuth, cesium, gallium, rubidium, silver, strontium, thallium, thorium and vanadium using ICPMS. In general most metals concentrations were low and below the analytical limit of detection with some high concentrations observed. Few factors examined in regression models were shown to influence biological metals concentrations and explained little of the variation. Further study is required to establish the source of metals exposures at the high end of the ranges of concentrations measured and the potential for any adverse health impacts in children.
Fulltext Synthesis Mechanism and Thermal Optimization of an Economical Mesoporous Material Using Silica: Implications for the Effective Removal or Delivery of Ibuprofen

Kittappa S, Cui M, Ramalingam M, Ibrahim S, Khim J, Yoon Y, et al.

PLoS One, 2015;10(7):e0130253.
PMID: 26161510 DOI: 10.1371/journal.pone.0130253

Mesoporous silica materials (MSMs) were synthesized economically using silica (SiO2) as a precursor via a modified alkaline fusion method. The MSM prepared at 500°C (MSM-500) had the highest surface area, pore size, and volume, and the results of isotherms and the kinetics of ibuprofen (IBP) removal indicated that MSM-500 had the highest sorption capacity and fastest removal speed vs. SBA-15 and zeolite. Compared with commercial granular activated carbon (GAC), MSM-500 had a ~100 times higher sorption rate at neutral pH. IBP uptake by MSM-500 was thermodynamically favorable at room temperature, which was interpreted as indicating relatively weak bonding because the entropy (∆adsS, -0.07 J mol(-1) K(-1)) was much smaller. Five times recycling tests revealed that MSM-500 had 83-87% recovery efficiencies and slower uptake speeds due to slight deformation of the outer pore structure. In the IBP delivery test, MSM-500 drug loading was 41%, higher than the reported value of SBA-15 (31%). The in vitro release of IBP was faster, almost 100%, reaching equilibrium within a few hours, indicating its effective loading and unloading characteristics. A cost analysis study revealed that the MSM was ~10-70 times cheaper than any other mesoporous silica material for the removal or delivery of IBP.
Fulltext Teeth and Covariates: Association with Risk of Falls

Kohli S, Wui Vun AL, Daryl Philip C, Muhammad Aadil C, Ramalingam M

Int J Dent, 2018;2018:7127209.
PMID: 30034470 DOI: 10.1155/2018/7127209

Purpose: Falls occur commonly in geriatric populations and undesirably influence their life, morbidity, and mortality. The aim of this study was to analyze the association between the number of teeth present among the elderly population and covariates in relation to the risk of falls.
Materials and Methods: This study was conducted at various old age homes in the Klang Valley region of Malaysia involving the geriatric population aged 60 years and above. A detailed questionnaire consisting of sociodemographic data including sex, age, household income, and dental variables such as the number of teeth and chewing difficulty was obtained. The Tinetti test (TT) was used to evaluate the patients' ability to walk, to maintain postural balance, and to determine their risk of falling. The short version of the Geriatric Depression Scale was used to assess depression among the participants, and the Barthel Scale was used to analyze the subject's ability to perform the activities of daily living (ADL).
Results: Statistically significant association was observed in relation to the number of teeth present and risk of falls (p < 0.05). Subjects who had 19 teeth or less in total had moderate to highest risk of falls (p=0.001) in comparison with subjects who had 20 teeth or more. Those aged 70 years and above showed the highest risk of falls (p=0.001) in comparison with the subjects aged between 60 and 69 years. Subjects with depression (p=0.03) and presence of illness related to fall showed statistically significant difference (p=0.001) in comparison with those who did not suffer from the same. Compromised ADL (p=0.001) (which included ability to perform several tasks like indoor mobility, climbing stairs, toilet use, and feeding) and low monthly income (p=0.03) was also observed among subjects who had higher risk of falls.
Conclusion: According to the results achieved, there was a high statistically significant association observed between the number of teeth present, age, depression, ADL, and presence of illness in relation to the risk of falling among the geriatric population. Henceforth, oral rehabilitation of elderly patients with less number of teeth may reduce their risk of falls.
Fulltext The impact of endometrial thickness (EMT) on the day of human chorionic gonadotropin (hCG) administration on pregnancy outcomes: a 5-year retrospective cohort analysis in Malaysia

Chan JM, Sukumar AI, Ramalingam M, Ranbir Singh SS, Abdullah MF

Fertil Res Pract, 2018;4:5.
PMID: 30116547 DOI: 10.1186/s40738-018-0050-8

Background: Chances of pregnancy in relation to endometrial thickness (EMT) remain elusive albeit some literatures suggest poorer pregnancy outcomes below the threshold of 6-7 mm, notwithstanding others perceive detrimental effect at thicker EMT. We aim to examine the implication of EMT on pregnancy outcomes using a cut-off of 8 mm and further explore for any effect of 'thick' EMT in our patient population.
Methods: This was a retrospective cohort study performed for 162 women to assess the associations between EMT on the human chorionic ganadotropin (hCG) trigger day and pregnancy outcomes in infertile patients undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) and autologous fresh embryo transfer (ET) in controlled ovarian stimulation (COS) cycles under an assisted reproductive technology (ART) shared-care programme between public and private institutions from January 2012 through December 2016.The associations between pregnancy outcomes [Total Pregnancy Rate (TPR), Biochemical Pregnancy Rate (BPR), Clinical Pregnancy Rate (CPR), Ongoing Pregnancy Rate (OPR)/ Live Birth Delivery Rate (LBDR), Miscarriage Rate (MR) and Implantation Rate (IR)] and EMT ( 0.05). All pregnancy outcomes were comparable for ≥14 mm and ≥ 8 to
Anxiety, depression and marital satisfaction in women with hyperemesis gravidarum: A comparative cross-sectional study in Hospital Tengku Ampuan Rahimah, Klang, Malaysia

Azlan WAW, Ramalingam M, Razali R, Abdullah MF, Rahman FNA

Asia Pac Psychiatry, 2022 Mar;14(1):e12416.
PMID: 32929893 DOI: 10.1111/appy.12416

INTRODUCTION: Hyperemesis Gravidarum (HG) is a severe form of vomiting that occurs among pregnant mothers. Due to the nature of HG, pregnant mothers may feel fatigued and burdened by it and questions have been raised about the emergence of psychiatric illness during this period of vulnerability.
METHODS: A comparative cross-sectional study using Hospital Anxiety and Depression Scale (HADS), M.I.N.I (MINI International Neuropsychiatric Interview) and ENRICH- EMS (Evaluation and Nurturing Relationship Issues, Communication and Happiness - Marital Satisfaction Scale) were performed in a group of 112 pregnant women.
RESULTS: There were no differences in the prevalence rate of any anxiety disorder among the patient with HG vs comparative group (9% vs 3%, P > 0.05) and depressive disorder in women with HG vs comparative group (16% vs 8%, P > 0.05) respectively. There were associations between HG and gravida, past history of miscarriage, and gestational diabetes (P
Fulltext Characterization of vanillin carbon isotope delta reference materials

Chartrand MMG, Meija J, Hélie JF, Middlestead P, Ramalingam M, Aziz AA, et al.

Anal Bioanal Chem, 2022 Nov;414(27):7877-7883.
PMID: 36198919 DOI: 10.1007/s00216-022-04322-x

Stable carbon isotope ratio measurements are used to investigate the provenance of vanillin. In this study, a variety of commercial vanillin samples and vanilla products were analyzed to provide a frame of reference for the variability of carbon isotope delta values in various vanillin samples, with the results ranging from -20.6 to -36.7‰ relative to the Vienna Peedee Belemnite (VPDB). We present information on the development of two synthetic vanillin reference materials, VANA-1 and VANB-1, prepared in 0.75 g units in glass vials, to be used for the calibration of carbon isotope delta measurements of vanillin and other easily combustible organic materials. Characterization of 40 vials each of VANA-1 and VANB-1 was performed by three laboratories over several measurement sequences. The certified carbon isotope delta values are -31.30 ± 0.06‰ (VANA-1) and -25.85 ± 0.05‰ (VANB-1). These uncertainties, for the 95% confidence level, include considerations for measurement uncertainty, coherence of the reference materials used for calibration, batch homogeneity, and stability during storage and transportation. The results are traceable to the VPDB through a set of nine reference materials (IAEA-CH-6, USGS65, IAEA-600, NBS22, USGS61, IAEA-603, IAEA-610, IAEA-611, and IAEA-612). For up to date certified values, users should refer to doi.org/10.4224/crm.2022.vana-1 and doi.org/10.4224/crm.2022.vanb-1.
Conversion of seaweed waste to biochar for the removal of heavy metal ions from aqueous solution: A sustainable method to address eutrophication problem in water bodies

Ravindiran G, Rajamanickam S, Ramalingam M, Hayder G, Sathaiah BK, Gaddam MKR, et al.

Environ Res, 2024 Jan 15;241:117551.
PMID: 37939801 DOI: 10.1016/j.envres.2023.117551

The present study investigated the sustainable approach for wastewater treatment using waste algal blooms. The current study investigated the removal of toxic metals namely chromium (Cr), nickel (Ni), and zinc (Zn) from aqueous solutions in batch and column studies using biochar produced by the marine algae Ulva reticulata. SEM/EDX, FTIR, and XRD were used to examine the adsorbents' properties and stability. The removal efficiency of toxic metals in batch operations was investigated by varying the parameters, which included pH, biochar dose, initial metal ion concentration, and contact time. Similarly, in the column study, the removal efficiency of heavy metal ions was investigated by varying bed height, flow rate, and initial metal ion concentration. Response Surface Methodology (Central Composite Design (CCD)) was used to confirm the linearity between the observed and estimated values of the adsorption quantity. The packed bed column demonstrated successful removal rates of 90.38% for Cr, 91.23% for Ni, and 89.92% for Zn heavy metals from aqueous solutions, under a controlled environment. The breakthrough analysis also shows that the Thomas and Adams-Bohart models best fit the regression values, allowing prior breakthroughs in the packed bed column to be predicted. Desorption studies were conducted to understand sorption and elution during different regeneration cycles. Adding 0.3 N sulfuric acid over 40 min resulted in the highest desorption rate of the column and adsorbent used for all three metal ions.