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Tailoring molecularly imprinted polymer on titanium-multiwalled carbon nanotube functionalized gold electrode for enhanced chlorophyll determination in microalgae health assessment

Ramanathan S, Lau WJ, Goh PS, Gopinath SCB, Rawindran H, Omar MF, et al.

Mikrochim Acta, 2024 Sep 10;191(10):586.
PMID: 39251454 DOI: 10.1007/s00604-024-06662-0

A unique method for determining chlorophyll content in microalgae is devised employing a gold interdigitated electrode (G-IDE) with a 10-µm gap, augmented by a nano-molecularly imprinted polymer (nano-MIP) and a titanium dioxide/multiwalled carbon nanotube (TiO2/MWCNT) nanocomposite. The nano-MIP, produced using chlorophyll template voids, successfully trapped chlorophyll, while the TiO2/MWCNT nanocomposite, synthesized by the sol-gel technique, exhibited a consistent distribution and anatase crystalline structure. The rebinding of procured chlorophyll powder, which was used as a template for nano-MIP synthesis, was identified with a high determination coefficient (R2 = 0.9857). By combining the TiO2/MWCNT nanocomposite with nano-MIP, the G-IDE sensing method achieved a slightly better R2 value of 0.9892 for detecting chlorophyll in microalgae. The presented G-IDE sensor showed a significant threefold enhancement in chlorophyll detection compared with commercially available chlorophyll powder. It had a detection limit of 0.917 mL (v/v) and a linear range that spanned from 10-6 to 1 mL. The effectiveness of the sensor in detecting chlorophyll in microalgae was confirmed through validation of its repeatability and reusability.
Fulltext Investigation of the Adrenergic and Opioid Binding Affinities, Metabolic Stability, Plasma Protein Binding Properties, and Functional Effects of Selected Indole-Based Kratom Alkaloids

Obeng S, Kamble SH, Reeves ME, Restrepo LF, Patel A, Behnke M, et al.

J Med Chem, 2020 01 09;63(1):433-439.
PMID: 31834797 DOI: 10.1021/acs.jmedchem.9b01465

Selected indole-based kratom alkaloids were evaluated for their opioid and adrenergic receptor binding and functional effects, in vivo antinociceptive effects, plasma protein binding, and metabolic stability. Mitragynine, the major alkaloid in Mitragyna speciosa (kratom), had higher affinity at opioid receptors than at adrenergic receptors while the vice versa was observed for corynantheidine. The observed polypharmacology of kratom alkaloids may support its utilization to treat opioid use disorder and withdrawal.
Kratom and Pain Tolerance: A Randomized, Placebo-Controlled, Double-Blind Study

Vicknasingam B, Chooi WT, Rahim AA, Ramachandram D, Singh D, Ramanathan S, et al.

Yale J Biol Med, 2020 06;93(2):229-238.
PMID: 32607084

Background: Kratom has a long history of traditional medicine use in Southeast Asia. Consumption of kratom products has also been reported in the US and other regions of the world. Pain relief is among many self-reported kratom effects but have not been evaluated in controlled human subject research. Methods: Kratom effects on pain tolerance were assessed in a randomized, placebo-controlled, double-blind study. During a 1-day inpatient stay, participants received a randomized sequence of kratom and placebo decoctions matched for taste and appearance. Pain tolerance was measured objectively in a cold pressor task (CPT) as time (seconds) between the pain onset and the hand withdrawal from the ice bath. Health status, vital signs, objective, and subjective indicators of withdrawal symptoms, self-reported data on lifetime kratom use patterns, and assessments of blinding procedures were also evaluated. Results: Twenty-six males with the mean (SD) age 24.3 (3.4) years were enrolled. They reported the mean (SD) 6.1 (3.2) years of daily kratom consumption. Pain tolerance increased significantly 1 hour after kratom ingestion from the mean (SD) 11.2 (6.7) seconds immediately before to 24.9 (39.4) seconds 1 hour after kratom consumption (F(2,53.7)=4.33, p=0.02). Pain tolerance was unchanged after consuming placebo drinks: 15.0 (19.0) seconds immediately before and 12.0 (8.1) seconds 1 hour after consumption of placebo (F(2,52.8)=0.93, p=0.40). No discomfort or signs of withdrawal were reported or observed during 10-20 hours of kratom discontinuation. Conclusions: Kratom decoction demonstrated a substantial and statistically significant increase in pain tolerance. Further rigorous research on kratom pain-relieving properties and a safety profile is needed.
Fulltext Synchronous Breast and Cervical Carcinoma: A Genetic Point of View

Yahya MM, Ismail MP, Ramanathan S, Kadir MN, Azhar A, Ibrahim NBC, et al.

Biomedicines, 2023 Feb 11;11(2).
PMID: 36831061 DOI: 10.3390/biomedicines11020525

Breast carcinoma is the most common cancer of women in Malaysia. The most common sites of metastasis are the lung, liver, bone and brain. A 45-year-old lady was diagnosed with left invasive breast carcinoma stage IV (T4cN1M1) with axillary lymph nodes and lung metastasis. She was noted to have a cervical mass through imaging, and biopsy showed CIN III. Post chemotherapy, the patient underwent left simple mastectomy with examination under anaesthesia of the cervix, cystoscopy and staging. The cervical histopathological examination (HPE) showed squamous cell carcinoma, and clinical staging was 2A. The breast tissue HPE showed invasive carcinoma with triple receptors positivity. The patient was given tamoxifen and put on concurrent chemoradiotherapy (CCRT) for the cervical cancer. The management of each pathology of this patient involved a multi-disciplinary team that included surgeons, oncologists, gynaecologists, pathologists and radiologists. Due to the complexity of the case with two concurrent cancers, the gene expression profiles may help predict the patient's clinical outcome.
Fulltext Prerequisite for COVID-19 Prediction: A Review on Factors Affecting the Infection Rate

Tang SGH, Hadi MHH, Arsad SR, Ker PJ, Ramanathan S, Afandi NAM, et al.

Int J Environ Res Public Health, 2022 Oct 11;19(20).
PMID: 36293576 DOI: 10.3390/ijerph192012997

Since the year 2020, coronavirus disease 2019 (COVID-19) has emerged as the dominant topic of discussion in the public and research domains. Intensive research has been carried out on several aspects of COVID-19, including vaccines, its transmission mechanism, detection of COVID-19 infection, and its infection rate and factors. The awareness of the public related to the COVID-19 infection factors enables the public to adhere to the standard operating procedures, while a full elucidation on the correlation of different factors to the infection rate facilitates effective measures to minimize the risk of COVID-19 infection by policy makers and enforcers. Hence, this paper aims to provide a comprehensive and analytical review of different factors affecting the COVID-19 infection rate. Furthermore, this review analyses factors which directly and indirectly affect the COVID-19 infection risk, such as physical distance, ventilation, face masks, meteorological factor, socioeconomic factor, vaccination, host factor, SARS-CoV-2 variants, and the availability of COVID-19 testing. Critical analysis was performed for the different factors by providing quantitative and qualitative studies. Lastly, the challenges of correlating each infection risk factor to the predicted risk of COVID-19 infection are discussed, and recommendations for further research works and interventions are outlined.
Exploring the Chemistry of Alkaloids from Malaysian Mitragyna speciosa (Kratom) and the Role of Oxindoles on Human Opioid Receptors

Chear NJ, León F, Sharma A, Kanumuri SRR, Zwolinski G, Abboud KA, et al.

J Nat Prod, 2021 04 23;84(4):1034-1043.
PMID: 33635670 DOI: 10.1021/acs.jnatprod.0c01055

Ten indole and oxindole alkaloids (1-10) were isolated from the freshly collected leaves of Malaysian Mitragyna speciosa (Kratom). The chemical structures of these compounds were established on the basis of extensive 1D and 2D NMR and HRMS data analysis. The spectroscopic data of mitragynine oxindole B (4) are reported herein for the first time. The spatial configuration of mitragynine oxindole B (4) was confirmed by single-crystal X-ray diffraction. Simultaneous quantification of the isolated alkaloids in the M. speciosa leaf specimens collected from different locations in the northern region of Peninsular Malaysia was also performed using UPLC-MS/MS. The oxindole alkaloids (1-4) and the indole alkaloid (10) were assessed for binding affinity at opioid receptors. Corynoxine (1) showed high binding affinity to μ-opioid receptors with a Ki value of 16.4 nM. Further, corynoxine (1) was 1.8-fold more potent than morphine in rats subjected to a nociceptive hot plate assay. These findings have important implications for evaluating the combined effects of the minor oxindole alkaloids in the overall therapeutic activity of M. speciosa.
Determinants of microalbuminuria among type 2 diabetes mellitus patients in Kuala Selangor district: A cross-sectional study

Shahrir NF, Aziz NRA, Ahmad FL, Muzaid NA, Samat F, Syed Ghazaili SNA, et al.

Malays Fam Physician, 2022 Nov 30;17(3):53-63.
PMID: 36606172 DOI: 10.51866/oa.122

INTRODUCTION: Microalbuminuria presents significant health risks for the progression of endstage renal-failure (ESRF) among type 2 diabetes mellitus (T2DM) patients. This study aims to determine the proportion and associated factors of microalbuminuria among T2DM patients in Kuala Selangor district, Malaysia.
METHOD: A retrospective cross-sectional study was conducted from December 2020 to February 2021 using secondary data from the National Diabetic Registry (NDR), Malaysia, and reviewed patients' diabetic records for the year 2020. All T2DM patients aged >18 years who were registered with the NDR in 2020 and fulfilled the inclusion and exclusion criteria were included in the study. Descriptive statistics and multiple logistic regression analysis were performed. Data were analysed using SPSS version 26.0. A total of 343 samples were included in this study for the determination of the proportion of microalbuminuria and its associated factors.
RESULTS: Of 343 respondents, 34.4% had microalbuminuria. HbAlc >7.0% (AdjOR 2.19, 95% CI: 1.35, 3.55, p=0.001), HDL <1.04 mmol/L (AdjOR 2.44, 95% CI: 1.323, 4.52, p=0.004), dyslipidaemia (AdjOR 1.90, 95% CI: 1.03, 3.48, p=0.039), and peripheral neuropathy (AdjOR 3.01, 95% CI: 1.02, 8.93, p=0.047) were significantly associated with microalbuminuria. Conclusion: Microalbuminuria is a modifiable risk factor in preventing the progression of ESRF among T2DM patients. Therefore, identification of factors associated with microalbuminuria among this high-risk group is important to facilitate early screening and prompt treatment to prevent progression of diabetic kidney disease to ESRF.
Evaluation of toxicity profile of kratom (Mitragyna speciosa Korth) decoction in rats

Hassan Z, Singh D, Suhaimi FW, Chear NJ, Harun N, See CP, et al.

Regul Toxicol Pharmacol, 2023 Sep;143:105466.
PMID: 37536550 DOI: 10.1016/j.yrtph.2023.105466

Mitragyna speciosa Korth also known as kratom, is an herbal drug preparation for its therapeutic properties and opioid-replacement therapy. Kratom is consumed in a brewed decoction form in Malaysia and to date, no studies have characterized its chemical and toxicity profile. Thus, this study aims to evaluate kratom decoction's safety and toxicity profile after 28 days of treatment. Mitragynine content was quantified in kratom decoction and used as a marker to determine the concentration. Male and female Sprague Dawley rats were orally treated with vehicle or kratom decoction (10, 50 or 150 mg/kg) and two satellite groups were treated with vehicle and kratom decoction (150 mg/kg). Blood and organs were collected for hematology, biochemical and histopathology analysis at the end of treatment. No mortality was found after 28 days of treatment and no significant changes in body weight and hematology profile, except for low platelet count. High amounts of uric acid, AST, ALT and alkaline phosphatase were found in the biochemical analysis. Histological investigation of the heart and lungs detected no alterations except for the kidney, liver and brain tissues. In conclusion, repeated administration of kratom decoction provided some evidence of toxicity in the kidney and liver with no occurrence of mortality.
Fulltext Treatment of MOG antibody associated disorders: results of an international survey

Whittam DH, Karthikeayan V, Gibbons E, Kneen R, Chandratre S, Ciccarelli O, et al.

J Neurol, 2020 Dec;267(12):3565-3577.
PMID: 32623595 DOI: 10.1007/s00415-020-10026-y

INTRODUCTION: While monophasic and relapsing forms of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are increasingly diagnosed world-wide, consensus on management is yet to be developed.
OBJECTIVE: To survey the current global clinical practice of clinicians treating MOGAD.
METHOD: Neurologists worldwide with expertise in treating MOGAD participated in an online survey (February-April 2019).
RESULTS: Fifty-two responses were received (response rate 60.5%) from 86 invited experts, comprising adult (78.8%, 41/52) and paediatric (21.2%, 11/52) neurologists in 22 countries. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ≥ 3 months; though less commonly when treating children. After an index event, 60% (31/51) usually start steroid-sparing maintenance therapy (MT); after ≥ 2 attacks 92.3% (48/52) would start MT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on MT initiation. Commonly used first line MTs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line MT (54.5%; 6/11). Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop MT.
CONCLUSION: Current treatment of MOGAD is highly variable, indicating a need for consensus-based treatment guidelines, while awaiting definitive clinical trials.
Genomic analyses in Cornelia de Lange Syndrome and related diagnoses: Novel candidate genes, genotype-phenotype correlations and common mechanisms

Kaur M, Blair J, Devkota B, Fortunato S, Clark D, Lawrence A, et al.

Am J Med Genet A, 2023 Aug;191(8):2113-2131.
PMID: 37377026 DOI: 10.1002/ajmg.a.63247

Cornelia de Lange Syndrome (CdLS) is a rare, dominantly inherited multisystem developmental disorder characterized by highly variable manifestations of growth and developmental delays, upper limb involvement, hypertrichosis, cardiac, gastrointestinal, craniofacial, and other systemic features. Pathogenic variants in genes encoding cohesin complex structural subunits and regulatory proteins (NIPBL, SMC1A, SMC3, HDAC8, and RAD21) are the major pathogenic contributors to CdLS. Heterozygous or hemizygous variants in the genes encoding these five proteins have been found to be contributory to CdLS, with variants in NIPBL accounting for the majority (>60%) of cases, and the only gene identified to date that results in the severe or classic form of CdLS when mutated. Pathogenic variants in cohesin genes other than NIPBL tend to result in a less severe phenotype. Causative variants in additional genes, such as ANKRD11, EP300, AFF4, TAF1, and BRD4, can cause a CdLS-like phenotype. The common role that these genes, and others, play as critical regulators of developmental transcriptional control has led to the conditions they cause being referred to as disorders of transcriptional regulation (or "DTRs"). Here, we report the results of a comprehensive molecular analysis in a cohort of 716 probands with typical and atypical CdLS in order to delineate the genetic contribution of causative variants in cohesin complex genes as well as novel candidate genes, genotype-phenotype correlations, and the utility of genome sequencing in understanding the mutational landscape in this population.

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