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Oral manifestations of microbial diseases

Singh G, Krishnan S

Med J Malaysia, 1978 Mar;32(3):232-5.
PMID: 683048
Fulltext Detecting industrial motor faults with current signatures

Krishnan S, Vengadasalam V

F1000Res, 2021;10:903.
PMID: 36398279 DOI: 10.12688/f1000research.54266.1

Background: A major player in industry is the induction motor. The constant motion and mechanical nature of motors causes much wear and tear, creating a need for frequent maintenance such as changing contact brushes. Unmannered and infrequent monitoring of motors, as is common in the industry, can lead to overexertion and cause major faults. If a motor fault is detected earlier through the use of automated fault monitoring, it could prevent minor faults from developing into major faults, reducing the cost and down-time of production due the motor repairs. There are few available methods to detect three-phase motor faults. One method is to analyze average vibration signals values of V, I, pf, P, Q, S, THD and frequency. Others are to analyze instantaneous signal signatures of V and I frequencies, or V and I trajectory plotting a Lissajous curve. These methods need at least three sensors for current and three for voltage for a three-phase motor detection. Methods: Our proposed method of monitoring faults in three-phase industrial motors uses Hilbert Transform (HT) instantaneous current signature curve only, reducing the number of sensors required. Our system detects fault signatures accurately at any voltage or current levels, whether it is delta or star connected motors. This is due to our system design, which incorporates normalized curves of HT in the fault analysis database. We have conducted this experiment in our campus laboratory for two different three-phase motors with four different fault experiments. Results: The results shown in this paper are a comparison of two methods, the V and I Lissajous trajectory curve and our HT instantaneous current signature curve. Conclusion: We have chosen them as our benchmark as their fault results closely resemble our system results, but our system benefits such as universality and a cost reduction in sensors of 50%.
Design, synthesis, and evaluation of thiazolidinone derivatives as antimicrobial and anti-viral agents

Ravichandran V, Jain A, Kumar KS, Rajak H, Agrawal RK

Chem Biol Drug Des, 2011 Sep;78(3):464-70.
PMID: 21615706 DOI: 10.1111/j.1747-0285.2011.01149.x

A series of 1,3-thiazolidin-4-one derivatives were prepared by the reaction of respective aromatic amine, aromatic aldehyde, and thioglycolic acid in dry benzene/toluene. The newly synthesized compounds were characterized on the basis of elemental analysis, IR, (1) HNMR, and mass spectra. The newly synthesized final compounds were evaluated for their in vitro antibacterial, antifungal, and anti-viral activities. Preliminary results indicated that some of the compounds demonstrated antibacterial activity in the range of 7-13 μg/mL, antifungal activity in the range of 13-17 μg/mL, comparable with the standard drugs, ciprofloxacin and fluconazole. Structure-activity relationship studies revealed that the nature of the substituents at the 2 and 3 positions of the thiazolidinone nucleus had a significant impact on the in vitro antimicrobial and anti-viral activity of these classes of agents.
A four-point clinical criteria distinguishes immune thrombocytopenia from acute lymphoblastic leukaemia

Lum SH, How SJ, Ariffin H, Krishnan S

Med J Malaysia, 2016 02;71(1):28-9.
PMID: 27130741

Immune thrombocytopenia is the most common diagnosis of isolated thrombocytopenia. The dilemma encountered by paediatricians is missing diagnosis of acute leukaemia in children with isolated thrombocytopenia. We demonstrated childhood ITP could be diagnosed using a four point clinical criteria without missing a diagnosis of acute leukaemia. Hence, bone marrow examination is not necessary in children with typical features compatible with ITP prior to steroid therapy. This can encourage paediatricians to choose steroid therapy, which is cheaper and non-blood product, as first line platelet elevating therapy in children with significant haemorrhage.
Fulltext Brinjal leaf diseases detection based on discrete Shearlet transform and Deep Convolutional Neural Network

Abisha S, Mutawa AM, Murugappan M, Krishnan S

PLoS One, 2023;18(4):e0284021.
PMID: 37018344 DOI: 10.1371/journal.pone.0284021

Different diseases are observed in vegetables, fruits, cereals, and commercial crops by farmers and agricultural experts. Nonetheless, this evaluation process is time-consuming, and initial symptoms are primarily visible at microscopic levels, limiting the possibility of an accurate diagnosis. This paper proposes an innovative method for identifying and classifying infected brinjal leaves using Deep Convolutional Neural Networks (DCNN) and Radial Basis Feed Forward Neural Networks (RBFNN). We collected 1100 images of brinjal leaf disease that were caused by five different species (Pseudomonas solanacearum, Cercospora solani, Alternaria melongenea, Pythium aphanidermatum, and Tobacco Mosaic Virus) and 400 images of healthy leaves from India's agricultural form. First, the original plant leaf is preprocessed by a Gaussian filter to reduce the noise and improve the quality of the image through image enhancement. A segmentation method based on expectation and maximization (EM) is then utilized to segment the leaf's-diseased regions. Next, the discrete Shearlet transform is used to extract the main features of the images such as texture, color, and structure, which are then merged to produce vectors. Lastly, DCNN and RBFNN are used to classify brinjal leaves based on their disease types. The DCNN achieved a mean accuracy of 93.30% (with fusion) and 76.70% (without fusion) compared to the RBFNN (82%-without fusion, 87%-with fusion) in classifying leaf diseases.
Fulltext OSC28: Relationship between Occlusion Schemes and Temporomandibular Disorders in Malaysian Population

Jain A, Sridevi U, Krishnan S, Morgan S

J Indian Prosthodont Soc, 2018 Oct;18(Suppl 1):S19.
PMID: 30532420 DOI: 10.4103/0972-4052.244619
Fulltext Griscelli syndrome

Ariffin H, Geikowski A, Chin TF, Chau D, Arshad A, Abu Bakar K, et al.

Med J Malaysia, 2014 Aug;69(4):193-4.
PMID: 25500851 MyJurnal

We report a case of Griscelli Syndrome (GS). Our patient initially presented with a diagnosis of haemophagocytic lymphistiocytosis (HLH). Subsequent microscopic analysis of the patient's hair follicle revealed abnormal distribution of melanosomes in the shaft, which is a hallmark for GS. Analysis of RAB27A gene in this patient revealed a homozygous mutation in exon 6, c.550C>T, p.R184X . This nonsense mutation causes premature truncation of the protein resulting in a dysfunctional RAB27A. Recognition of GS allows appropriate institution of therapy namely chemotherapy for HLH and curative haemotopoeitic stem cell transplantation.
Pediatric Vaginal Yolk Sac Tumor: Reappraisal of Treatment Strategy in a Rare Tumor at a Unique Location

Rajagopal R, Ariffin H, Krishnan S, Abdullah WA, Lin HP

J Pediatr Hematol Oncol, 2015 Jul;37(5):391-5.
PMID: 25929614 DOI: 10.1097/MPH.0000000000000344

Review of the management of 6 young girls with vaginal yolk sac tumor over 25 years showed that the α-fetoprotein levels normalized in 5/6 within 4 cycles of primary cisplatin, bleomycin, etoposide (PEB)/carboplatin, etoposide, bleomycin (JEB)/cisplatin, vinblastine, bleomycin (PVB) chemotherapy. Radioimaging revealed residual tissue but viable tumor was found in only 1 of 2 biopsied. Resection/biopsy is necessary to avoid giving additional primary chemotherapy or to identify patients who need different treatment. If markers do not decay appropriately, PEB/JEB/PVB chemotherapy should not be continued. Taxol-containing salvage chemotherapy regimens, adjuvant modern radiotherapeutic treatment, and fertility-saving curative surgery should then be considered. Despite having mostly advanced disease, 5/6 patients were cured, 2 with chemotherapy alone.
Isolation of subgenus B adenovirus during a fatal outbreak of enterovirus 71-associated hand, foot, and mouth disease in Sibu, Sarawak

Cardosa MJ, Krishnan S, Tio PH, Perera D, Wong SC

Lancet, 1999 Sep 18;354(9183):987-91.
PMID: 10501361

In mid-1997, several children died in Sarawak, Malaysia, during an epidemic of enterovirus-71 (EV71) hand, foot, and mouth disease. The children who died had a febrile illness that rapidly progressed to cardiopulmonary failure and the cause was not satisfactorily resolved. We describe the isolation and identification of a subgenus B adenovirus from the children who died.
Primary hyperparathyroidism presenting with pathological fracture

Deshmukh RG, Alsagoff SA, Krishnan S, Dhillon KS, Khir AS

J R Coll Surg Edinb, 1998 Dec;43(6):424-7.
PMID: 9990797

Primary hyperparathyroidism (PHPT) is an intriguing condition. Routine automated biochemical screening has made the diagnosis commonplace in developed countries and the disease is diagnosed early in its course when it is often asymptomatic. In developing countries or in recent immigrants from these countries, PHPT is often seen in an advanced stage with bone involvement. Associated dietary deficiencies may alter the biochemical profile and cause a diagnostic dilemma. It is important to include it in the differential diagnosis of pathological fractures. We report three cases of PHPT presenting with pathological fractures and discuss their diagnosis and management.
Mature B-cell acute lymphoblastic leukaemia associated with a rare MLL-FOXO4 fusion gene

Lim L, Chen KS, Krishnan S, Gole L, Ariffin H

Br J Haematol, 2012 Jun;157(6):651.
PMID: 22429121 DOI: 10.1111/j.1365-2141.2012.09091.x
The role of iron-based nanoparticles (Fe-NPs) on methanogenesis in anaerobic digestion (AD) performance

Jadhav P, Khalid ZB, Zularisam AW, Krishnan S, Nasrullah M

Environ Res, 2021 Sep 17;204(Pt B):112043.
PMID: 34543635 DOI: 10.1016/j.envres.2021.112043

Several strategies have been proposed to improve the performance of the anaerobic digestion (AD) process. Among them, the use of various nanoparticles (NPs) (e.g. Fe, Ag, Cu, Mn, and metal oxides) is considered one of the most effective approaches to enhance the methanogenesis stage and biogas yield. Iron-based NPs (zero-valent iron with paramagnetic properties (Fe0) and iron oxides with ferromagnetic properties (Fe3O4/Fe2O3) enhance microbial activity and minimise the inhibition effect in methanogenesis. However, comprehensive and up-to-date knowledge on the function and impact of Fe-NPs on methanogens and methanogenesis stages in AD is frequently required. This review focuses on the applicative role of iron-based NPs (Fe-NPs) in the AD methanogenesis step to provide a comprehensive understanding application of Fe-NPs. In addition, insight into the interactions between methanogens and Fe-NPs (e.g. role of methanogens, microbe interaction and gene transfer with Fe-NPs) beneficial for CH4 production rate is provided. Microbial activity, inhibition effects and direct interspecies electron transfer through Fe-NPs have been extensively discussed. Finally, further studies towards detecting effective and optimised NPs based methods in the methanogenesis stage are reported.
Fulltext GATA1 mutations in a cohort of Malaysian children with Down syndrome-associated myeloid disorder

Lum SH, Choong SS, Krishnan S, Mohamed Z, Ariffin H

Singapore Med J, 2016 Jun;57(6):320-4.
PMID: 27353457 DOI: 10.11622/smedj.2016106

INTRODUCTION: Children with Down syndrome (DS) are at increased risk of developing distinctive clonal myeloid disorders, including transient abnormal myelopoiesis (TAM) and myeloid leukaemia of DS (ML-DS). TAM connotes a spontaneously resolving congenital myeloproliferative state observed in 10%-20% of DS newborns. Following varying intervals of apparent remission, a proportion of children with TAM progress to develop ML-DS in early childhood. Therefore, TAM and ML-DS represent a biological continuum. Both disorders are characterised by recurring truncating somatic mutations of the GATA1 gene, which are considered key pathogenetic events.
METHODS: We herein report, to our knowledge, the first observation on the frequency and nature of GATA1 gene mutations in a cohort of Malaysian children with DS-associated TAM (n = 9) and ML-DS (n = 24) encountered successively over a period of five years at a national referral centre.
RESULTS: Of the 29 patients who underwent GATA1 analysis, GATA1 mutations were observed in 15 (51.7%) patients, including 6 (75.0%) out of 8 patients with TAM, and 9 (42.9%) of 21 patients with ML-DS. All identified mutations were located in exon 2 and the majority were sequence-terminating insertions or deletions (66.7%), including several hitherto unreported mutations (12 out of 15).
CONCLUSION: The low frequency of GATA1 mutations in ML-DS patients is unusual and potentially indicates distinctive genomic events in our patient cohort.
Fulltext Implementation of a hepatitis-themed virtual escape room in pharmacy education: A pilot study

Krishnan S, Blebil AQ, Dujaili JA, Chuang S, Lim A

Educ Inf Technol (Dordr), 2023 Apr 05.
PMID: 37361790 DOI: 10.1007/s10639-023-11745-1

As we enter a world of blended learning in higher education, an increased need for adaptation of teaching strategies to enhance engagement has been recognised to amplify learning outcomes online. Gamification has been identified as a creative tool to engage the current cohort of learners who are also characteristically tech-savvy. To this end, escape room games have gained considerable traction in medical and pharmacy education to promote learning, critical thinking and teamwork. In this pilot study we describe the implementation of a 60-minute, web-based hepatitis-themed escape room game within a Year 3 Pharmacotherapy unit at Monash University. A total of 418 students participated in this activity. Students' knowledge gain on the topic was assessed through a pre- and post-intervention assessment, whereby a statistically significant improvement was seen in the knowledge score following implementation of the gaming activity (58.66% pre-intervention vs. 72.05% post-intervention, p
Pristine and modified biochar applications as multifunctional component towards sustainable future: Recent advances and new insights

Amalina F, Krishnan S, Zularisam AW, Nasrullah M

Sci Total Environ, 2024 Mar 01;914:169608.
PMID: 38157898 DOI: 10.1016/j.scitotenv.2023.169608

Employing biomass for environmental conservation is regarded as a successful and environmentally friendly technique since they are cost-effective, renewable, and abundant. Biochar (BC), a thermochemically converted biomass, has a considerably lower production cost than the other conventional activated carbons. This material's distinctive properties, including a high carbon content, good electrical conductivity (EC), high stability, and a large surface area, can be utilized in various research fields. BC is feasible as a renewable source for potential applications that may achieve a comprehensive economic niche. Despite being an inexpensive and environmentally sustainable product, research has indicated that pristine BC possesses restricted properties that prevent it from fulfilling the intended remediation objectives. Consequently, modifications must be made to BC to strengthen its physicochemical properties and, thereby, its efficacy in decontaminating the environment. Modified BC, an enhanced iteration of BC, has garnered considerable interest within academia. Many modification techniques have been suggested to augment BC's functionality, including its adsorption and immobilization reliability. Modified BC is overviewed in its production, functionality, applications, and regeneration. This work provides a holistic review of the recent advances in synthesizing modified BC through physical, chemical, or biological methods to achieve enhanced performance in a specific application, which has generated considerable research interest. Surface chemistry modifications require the initiation of surface functional groups, which can be accomplished through various techniques. Therefore, the fundamental objective of these modification techniques is to improve the efficacy of BC contaminant removal, typically through adjustments in its physical or chemical characteristics, including surface area or functionality. In addition, this article summarized and discussed the applications and related mechanisms of modified BC in environmental decontamination, focusing on applying it as an ideal adsorbent, soil amendment, catalyst, electrochemical device, and anaerobic digestion (AD) promoter. Current research trends, future directions, and academic demands were available in this study.
Fulltext Pertussis clinical case definition: Time for change in developing countries?

Gopal Krishnan S, Fun WH, Ramadras MD, Yunus R, Lye YF, Sararaks S

PLoS One, 2019;14(7):e0219534.
PMID: 31291359 DOI: 10.1371/journal.pone.0219534

BACKGROUND: Developing countries still struggle with late detection and mortality from pertussis. A review of clinical case definitions is necessary for early disease detection. This paper aimed to study possible clinical characteristics for earlier pertussis detection in a sporadic setting.
METHODS: We conducted a retrospective review of medical and laboratory records in a general paediatric ward of a district hospital in a developing country. Inclusion criteria were all children hospitalised with nasopharyngeal swab taken for Bordetella pertussis. We compared sensitivity and specificity of World Health Organization diagnostic criteria with other clinical characteristics. Polymerase chain reaction Bordetella pertussis was the gold standard used.
RESULTS: Out of 207 eligible admissions, the study retrieved 128 complete records. Approximately half of the children were less than 3 months old. The World Health Organization diagnostic criteria had a low sensitivity (15%), but high specificity (92%). In comparison, combinations that included paroxysmal cough, ill contact and facial congestion had higher sensitivity. Increasing cough duration improved specificity while compromising sensitivity.
CONCLUSION: Several clinical characteristics such as paroxysmal cough, facial congestion and a history of ill contact have potential for early clinical detection. Conventional emphasis on cough duration may hamper early detection.
Evaluating heavy metals contamination in soil and vegetables in the region of North India: Levels, transfer and potential human health risk analysis

Gupta N, Yadav KK, Kumar V, Krishnan S, Kumar S, Nejad ZD, et al.

Environ Toxicol Pharmacol, 2021 Feb;82:103563.
PMID: 33310081 DOI: 10.1016/j.etap.2020.103563

This study determined the heavy metals (HMs) accumulation in different vegetables in different seasons and attributed a serious health hazard to human adults due to the consumption of such vegetables in Jhansi. The total amounts of zinc (Zn), lead (Pb), nickel (Ni), manganese (Mn), copper (Cu), cobalt (Co), and cadmium (Cd) were analysed in 28 composite samples of soil and vegetables (Fenugreek, spinach, eggplant, and chilli) collected from seven agricultural fields. The transfer factor (TF) of HMs from soil to analysed vegetables was calculated, and significant non-carcinogenic health risks due to exposure to analysed heavy metals via consumption of these vegetables were computed. The statistical analysis involving Principal Component Analysis (PCA) and Pearson's correlation matrix suggested that anthropogenic activities were a major source of HMs in the study areas. The target hazard quotient of Cd, Mn, and Pb for fenugreek (2.156, 2.143, and 2.228, respectively) and spinach (3.697, 3.509, 5.539, respectively) exceeded the unity, indicating the high possibilities of non-carcinogenic health risks if regularly consumed by human beings. This study strongly suggests the continuous monitoring of soil, irrigation water, and vegetables to prohibit excessive accumulation in the food chain.
Fulltext Unexpected acceleration of Ultrasonic-Assisted iodide dosimetry in the catalytic presence of ionic liquids

Krishnan S, Abd Ghani N, Aminuddin NF, Quraishi KS, Razafindramangarafara BL, Baup S, et al.

Ultrason Sonochem, 2021 Jun;74:105576.
PMID: 33975186 DOI: 10.1016/j.ultsonch.2021.105576

This study investigates the potential of using small amounts of ionic liquids (IL) to enhance ultrasound-assisted extraction of lipids content from green microalgae. Three imidazolium-based ILs (butyl, octyl and dodecyl), each of them with two anions (bromide and acetate) were tested as additives. Viscosity and surface tension of the ILs aqueous mixtures were analyzed to determine the influence of ILs' anions and alkyl chain length, whereas KI dosimetry experiments were used as an indicator of radicals formation. A key finding suggests that the small addition of ILs improves the ultrasonication either by enhancing the viscosity and reducing the water surface tension, leading to a more powerful acoustic cavitation process or by increasing HO° production likely to oxidize the microalgae cells membranes, and consequently disrupting them on a more efficient manner. KI dosimetry also revealed that long ILs alkyl chain is detrimental. This experimental observation is confirmed thus strengthened as the yield of extracted lipids from green microalgae has shown an incremental trend when the IL concentration also increased. These hypotheses are currently under investigation to spot detailed impact of ILs on cavitation process.
Hypercalcaemia: an unusual presenting feature of childhood acute lymphoblastic leukaemia

Rajagopal R, Lum SH, Jalaludin MY, Krishnan S, Abdullah WA, Ariffin H

Br J Haematol, 2013 Oct;163(2):147.
PMID: 23961807 DOI: 10.1111/bjh.12500
Fulltext Anti-EGFR anchored paclitaxel loaded PLGA nanoparticles for the treatment of triple negative breast cancer. In-vitro and in-vivo anticancer activities

Venugopal V, Krishnan S, Palanimuthu VR, Sankarankutty S, Kalaimani JK, Karupiah S, et al.

PLoS One, 2018;13(11):e0206109.
PMID: 30408068 DOI: 10.1371/journal.pone.0206109

The aim of the present study is to analyze the viability of anti-EGFR anchored immunonanoparticle (INP) bearing Paclitaxel (PTX) to specifically bind the EGFR protein on the TNBC cells. The NP was prepared by nanoprecipitation and characterized the particle size, charge, entrapment of drug and release of it. The anti-EGFR anchored and the integrity was confirmed by SDS-PAGE. Cytotoxicity and NPs cellular uptake was analyzed with MDA-MB-468 type cancer cells and the EGFR expression was confirmed by PCR, qualitatively and quantitatively. The in-vivo antitumor activity of INP was determined by using athymic mice model and targeting efficiency was measured by calculating the PTX accumulation in the tumor plasma. The prepared INP with the size of 336.3 nm and the charge of -3.48 mV showed sustained drug release upto 48 h. The INP showed significant reduction of cancer cell viability of 10.6% for 48 h with 93 fold higher PTX accumulation in the tumor plasma compared with NPs. Based on these reports, we recommend that anti-EGFR anchored PTX loaded NP may have the ability to target the TNBC cells and improve the therapeutic action and subsidize the side effects of PTX for the treatment of TNBC.

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