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Fulltext Fused ring effect on optical nonlinearity and structure property relationship of anthracenyl chalcone based push-pull chromophores

Zainuri DA, Abdullah M, Zaini MF, Bakhtiar H, Arshad S, Abdul Razak I

PLoS One, 2021;16(9):e0257808.
PMID: 34582495 DOI: 10.1371/journal.pone.0257808

The Ultraviolet-visible (UV-Vis) spectra indicate that anthracenyl chalcones (ACs) have high maximum wavelengths and good transparency windows for optical applications and are suitable for optoelectronic applications owing to their HOMO-LUMO energy gaps (2.93 and 2.76 eV). Different donor substituents on the AC affect their dipole moments and nonlinear optical (NLO) responses. The positive, negative, and neutral electrostatic potential regions of the molecules were identified using molecular electrostatic potential (MEP). The stability of the molecule on account of hyperconjugative interactions and accompanying charge delocalization was analyzed using natural bond orbital (NBO) analysis. Open and closed aperture Z-scans were performed using a continuous-wave frequency-doubled diode-pumped solid-state (DPSS) laser to measure the nonlinear absorption and nonlinear refractive index coefficients, respectively. The valley-to-peak profile of AC indicated a negative nonlinear refractive index coefficient. The obtained single crystals possess reverse saturation absorption due to excited-state absorption. The structural and nonlinear optical properties of the molecules have been discussed, along with the role of anthracene substitution for enhancing the nonlinear optical properties. The calculated third-order susceptibility value was 1.10 x10-4 esu at an intensity of 4.1 kW/cm2, higher than the reported values for related chalcone derivatives. The NLO response for both ACs offers excellent potential in optical switching and limiting applications.
Diagnostic Challenge in Veterinary Pathology: Metastatic Mammary Tumor in a Female Tiger (Panthera Tigris)

Fraser C, Keong Kok M, Shameha Abdul Razak I, Puspitasari Y, Salleh A

Vet Pathol, 2024 Jul;61(4):508-511.
PMID: 38247139 DOI: 10.1177/03009858241226650
Fulltext Redetermination of the crystal structure of 2-oxo-1,3-thia-zolidin-4-iminium chloride

Muthukkumar M, Karthikeyan A, Poovarasan M, Ruckmani V, Rajaram D, Jegan Jennifer S, et al.

Acta Crystallogr E Crystallogr Commun, 2019 Apr 01;75(Pt 4):443-446.
PMID: 31161053 DOI: 10.1107/S2056989019003189

In the redetermination of the title compound, C3H5N2OS+·CI-, the asymmetric unit consists of one independent 2-oxo-1,3-thia-zolidin-4-iminium cation and one independent chloride anion. The cation inter-acts with a chloride anion via N-H⋯Cl hydrogen bonds forming a supra-molecular chain along [010]. These supra-molecular chains are further extended by weak C-H⋯Cl and C-H⋯O inter-actions, forming a two-dimensional network parallel to (001). The crystal structure is further stabilized by weak C-O⋯π inter-actions, supporting a three-dimensional architecture. The structure was previously determined by Ananthamurthy & Murthy [Z. Kristallogr. (1975). 8, 356-367] but has been redetermined with higher precision to allow the hydrogen-bonding patterns and supra-molecular inter-actions to be investigated.
Fulltext Crystal structures and Hirshfeld surface analyses of hypoxanthine salts involving 5-sulfosalicylate and perchlorate anions

Sathya U, Nirmalram JS, Gomathi S, Perdih F, Jegan Jennifer S, Abdul Razak I

Acta Crystallogr E Crystallogr Commun, 2022 Jun 01;78(Pt 6):574-583.
PMID: 36072155 DOI: 10.1107/S2056989022004753

Two salts of 1,9-di-hydro-purin-6-one (hypoxanthine), namely, 6-oxo-1,9-di-hydro-purin-7-ium 5-sulfosalicylate dihydrate, C5H5N4O+·C7H5O6S-·2H2O, (I), and 6-oxo-1,9-di-hydro-purin-7-ium perchlorate monohydrate, C5H5N4O+·ClO4 -·H2O, (II), have been synthesized and characterized using single-crystal X-ray diffraction and Hirshfeld analysis. In both salts, the hypoxanthine mol-ecule is protonated at the N7 position of the purine ring. In salt (I), the cation and anion are connected through N-H⋯O inter-actions. The protonated hypoxanthine cations of salt (I) form base pairs with another symmetry-related hypoxanthine cation through N-H⋯O hydrogen bonds with an R 2 2(8) ring motif, while in salt (II), the hypoxanthine cations are paired through a water mol-ecule via N-H⋯O and O-H⋯N hydrogen bonds with an R 3 3(11) ring motif. The packings within the crystal structures are stabilized by π-π stacking inter-actions in salt (I) and C-O⋯π inter-actions in salt (II). The combination of several inter-actions leads to the formation of supra-molecular sheets extending parallel to (010) in salts (I) and (II). Hirshfeld surface analysis and fingerprint plots reveal that O⋯H/H⋯O contacts play the major role in the crystal packing of each of the salts, with a 54.1% contribution in salt (I) and 62.3% in salt (II).
Fulltext A study of the crystal structures, supra-molecular patterns and Hirshfeld surfaces of bromide salts of hypoxanthine and xanthine

Sathya U, Nirmalram JS, Gomathi S, Dhivya D, Jegan Jennifer S, Abdul Razak I

Acta Crystallogr E Crystallogr Commun, 2022 Jun 01;78(Pt 6):652-659.
PMID: 36072131 DOI: 10.1107/S2056989022005278

Two new crystalline salts, namely, hypoxanthinium bromide monohydrate, C5H5N4O+·Br-·H2O (I) and xanthinium bromide monohydrate, C5H5N4O2 +·Br-·H2O (II), were synthesized and characterized by single-crystal X-ray diffraction technique and Hirshfeld surface analysis. The hypoxanthinium and xanthinium cations in salts I and II are both in the oxo-N(9)-H tautomeric form. The crystal packing of the two salts is governed predominantly by N-H⋯O, N-H⋯Br, C-H⋯Br and O-H⋯Br inter-actions described by R 2 3(9) and R 2 2(8) synthons. The crystal packing is also consolidated by carbon-yl⋯π inter-actions between symmetry-related hypoxanthinium (HX+ ) cations in salt I and xanthinium cations (XA+ ) in salt II. The combination of all these inter-actions leads to the formation of wave- and staircase-like architectures in salts I and II, respectively. The largest contributions to the overall Hirshfeld surface are from Br⋯H/H⋯Br contacts (22.3% in I and 25.4% in II) .
Fulltext catena-Poly[[bis-(1H-indole-5-carboxyl-ato-κ2 O,O')zinc(II)]-μ-4,4'-azobi-pyridine-κ2 N 1:N 1']

Sathya U, Nirmal Ram JS, Gomathi S, Jegan Jennifer S, Abdul Razak I

IUCrdata, 2021 May;6(Pt 5):x210522.
PMID: 36338268 DOI: 10.1107/S2414314621005228

The asymmetric unit of the title coordination polymer [Zn(C9H6NO2)2(C10H8N4)] n , consists of one ZnII cation, one bidentate 1H-indole-5-carboxyl-ate (I5C) anion and half of a 4,4'-azobi-pyridine (Abpy) neutral ligand. In the coordination polyhedron, the ZnII ion adopts a distorted octa-hedral geometry. The coordination polymer is stabilized by a combination of N-H⋯O and C-H⋯π inter-actions, which leads to the formation of wave-like two-dimensional coordination polymeric layers.
Mortality among elder abuse victims in rural Malaysia: A two-year population-based descriptive study

Yunus RM, Hairi NN, Choo WY, Hairi FM, Sooryanarayana R, Ahmad SN, et al.

J Elder Abuse Negl, 2017;29(1):59-71.
PMID: 27841737 DOI: 10.1080/08946566.2016.1260083

Our study aims at describing mortality among reported elder abuse experiences in rural Malaysia. This is a population-based cohort study with a multistage cluster sampling method. Older adults in Kuala Pilah (n = 1,927) were interviewed from November 2013 to May 2014. Mortality was traced after 2 years using the National Registration Department database. Overall, 139 (7.2%) respondents died. Fifteen (9.6%) abuse victims died compared to 124 (7.0%) not abused. Mortality was highest with financial abuse (13%), followed by psychological abuse (10.8%). There was a dose-response relationship between mortality and clustering of abuse: 7%, 7.7%, and 14.0% for no abuse, one type, and two types or more, respectively. Among abuse victims, 40% of deaths had ill-defined causes, 33% were respiratory-related, and 27% had cardiovascular and metabolic origin. Results suggest a link between abuse and mortality. Death proportions varied according to abuse subtypes and gender.
Fulltext Prevalence, transitions and factors predicting transition between frailty states among rural community-dwelling older adults in Malaysia

Ahmad NS, Hairi NN, Said MA, Kamaruzzaman SB, Choo WY, Hairi F, et al.

PLoS One, 2018;13(11):e0206445.
PMID: 30395649 DOI: 10.1371/journal.pone.0206445

OBJECTIVES: This study aims to describe the prevalence and transitions of frailty among rural-community dwelling older adults in Malaysia and to analyse factors associated with different states of frailty transition. Frailty was conceptualized using modified Fried phenotype from the Cardiovascular Health Study.
DESIGN: This is a prospective longitudinal study with 12-months follow up among older adults in Malaysia.
SETTING: Kuala Pilah, a district in Negeri Sembilan, which is one of the fourteen states in Malaysia.
PARTICIPANTS: 2,324 community-dwelling older Malaysians aged 60 years and older.
RESULTS: The overall prevalence of frailty in this study was 9.4% (95% CI 7.8-11.2). The prevalence increased at least three-fold with every 10 years of age. This increase was seen higher in women compared to men. Being frail was significantly associated with older age, women, and respondents with a higher number of chronic diseases, poor cognitive function and low socioeconomic status (p<0.05). During the 12-months follow-up, our study showed that the transition towards greater frailty states were more likely (22.9%) than transition toward lesser frailty states (19.9%) while majority (57.2%) remained unchanged. Multivariate logistic regression analysis showed that presence of low physical activity increased the likelihood of worsening transition towards greater frailty states by three times (OR 2.9, 95% CI 2.2-3.7) and lowered the likelihood of transition towards lesser frailty states (OR 0.3, 95% CI 0.2-0.4).
CONCLUSION: Frailty is reported among one in every eleven older adults in this study. The prevalence increased across age groups and was higher among women than men. Frailty possesses a dynamic status due to its potential reversibility. This reversibility makes it a cornerstone to delay frailty progression. Our study noted that physical activity conferred the greatest benefit as a modifiable factor in frailty prevention.
Prevalence of Co-Occurrence of Physical Frailty and Malnutrition and Its Associated Factors Among Community-Dwelling Older Adults in a Rural District, Malaysia

Mustaffa M, Hairi NN, Majid HA, Choo WY, Hairi FM, Peramalah D, et al.

Asia Pac J Public Health, 2024 Mar;36(2-3):210-218.
PMID: 38482611 DOI: 10.1177/10105395241238092

Frailty and malnutrition commonly co-occur but remains undetected and untreated in community settings. This study aimed to determine the prevalence of co-occurring frailty and malnutrition, and its associated factors among community-dwelling older adults in a rural setting in Malaysia. A cross-sectional study was conducted among adults aged ≥ 60 residing in Kuala Pilah district, Negeri Sembilan, Malaysia. Physical frailty and nutritional status were assessed using the Fried phenotype and the Mini Nutritional Assessment (MNA), respectively. Among 1855 participants, 6.4% had co-occurring frailty and at-risk/malnutrition and 11.3% had co-occurring prefrailty and at-risk/malnutrition. Older age, fair-to-poor self-rated health, long-term disease, polypharmacy, activities of daily living (ADLs) and instrumental ADLs' disabilities, cognitive impairment, and poor social support were associated with higher odds of co-occurring frailty and malnutrition. Therefore, beside early identification, targeted intervention is crucial to prevent or delay the progression of frailty and malnutrition in this population.
Sarcopenia and All-Cause Mortality Risk in Community-Dwelling Rural Malaysian Older Adults

Ramoo K, Hairi NN, Yahya A, Choo WY, Hairi FM, Ismail N, et al.

Asia Pac J Public Health, 2024 Mar;36(2-3):225-231.
PMID: 38482589 DOI: 10.1177/10105395241237811

Sarcopenia is associated with numerous adverse health outcomes, including frailty, disability, and mortality. Since the Asian Working Group for Sarcopenia 2019 guidelines, which were published in 2020, are relatively new, studies on the association between sarcopenia as defined by these guidelines and mortality are limited in the Asian region. Accordingly, this study aimed to examine the all-cause mortality risk associated with sarcopenia among community-dwelling older adults in rural Malaysia. This cohort study included 2404 older adults residing in Kuala Pilah District, Negeri Sembilan, Malaysia who were followed up for 83 months. The prevalence rates of sarcopenia and severe sarcopenia were 5.0% and 3.60%, respectively. Older adults with sarcopenia and severe sarcopenia had a 114% (hazard ratio [HR]: 2.14) and 146% (HR: 2.46) increased mortality risk compared with those without sarcopenia (HR: 2.14). Our findings indicate that early intervention is recommended to prevent sarcopenia in older adults.
Fulltext Elder mistreatment in a community dwelling population: the Malaysian Elder Mistreatment Project (MAESTRO) cohort study protocol

Choo WY, Hairi NN, Sooryanarayana R, Yunus RM, Hairi FM, Ismail N, et al.

BMJ Open, 2016 05 25;6(5):e011057.
PMID: 27225651 DOI: 10.1136/bmjopen-2016-011057

INTRODUCTION: Despite being now recognised as a global health concern, there is still an inadequate amount of research into elder mistreatment, especially in low and middle-income regions. The purpose of this paper is to report on the design and methodology of a population-based cohort study on elder mistreatment among the older Malaysian population. The study aims at gathering data and evidence to estimate the prevalence and incidence of elder mistreatment, identify its individual, familial and social determinants, and quantify its health consequences.
METHODS AND ANALYSIS: This is a community-based prospective cohort study using randomly selected households from the national census. A multistage sampling method was employed to obtain a total of 2496 older adults living in the rural Kuala Pilah district. The study is divided into two phases: cross-sectional study (baseline), and a longitudinal follow-up study at the third and fifth years. Elder mistreatment was measured using instrument derived from the previous literature and modified Conflict Tactic Scales. Outcomes of elder mistreatment include mortality, physical function, mental health, quality of life and health utilisation. Logistic regression models are used to examine the relationship between risk factors and abuse estimates. Cox proportional hazard regression will be used to estimate risk of mortality associated with abuse. Associated annual rate of hospitalisation and health visit frequency, and reporting of abuse, will be estimated using Poisson regression.
ETHICS AND DISSEMINATION: The study has been approved by the Medical Ethics Committee of the University of Malaya Medical Center (MEC Ref 902.2) and the Malaysian National Medical Research Register (NMRR-12-1444-11726). Written consent was obtained from all respondents prior to baseline assessment and subsequent follow-up. Findings will be disseminated to local stakeholders via forums with community leaders, and health and social welfare departments, and published in appropriate scientific journals and presented at conferences.