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Perak, Malaysia, mass poisoning. Tale of the Nine Emperor Gods and rat tail noodles

Cheng CT

Am J Forensic Med Pathol, 1992 Sep;13(3):261-3.
PMID: 1476136

In October 1988, a series of food poisoning cases occurred in the State of Perak in Malaysia. Most of the victims were children. Ultimately 13 children between the ages of 2.5 and 11 years died. Epidemiological investigations showed that the probable source of the poison was Loh See Fun, a noodles in the shape of a rat's tail. All the deceased ate the noodles from one supplier. Clinical and pathological findings were similar in each case. Postmortem examination was performed in 11 cases. Toxicological examination on organs in 10 cases showed a high concentration of aflatoxin in tissues of the deceased. High levels of boric acid were excreted from most of the victims. Histological examination of the liver in these cases showed necrotic changes found in aflatoxin poisoning. Combination of the epidemiological, clinical, toxicological, and pathological findings pointed to the fact that there was a common toxin or toxins responsible for the deaths. These were thought to be a combination of boric acid and aflatoxin.
Clinical safety profile of sildenafil in Singaporean men with erectile dysfunction: pre-marketing experience (ASSESS-I evaluation)

Lim PH, Ng FC, Cheng CW, Wong MY, Chee CT, Moorthy P, et al.

J Int Med Res, 2002 Mar-Apr;30(2):137-43.
PMID: 12025521 DOI: 10.1177/147323000203000206

Safety and tolerability of sildenafil citrate was assessed in a population subset of 60 Singaporean men with erectile dysfunction taken from the Asian Sildenafil Efficacy and Safety Study (ASSESS-I), a double-blind, placebo-controlled, flexible-dose study. The men, from two centres, with > or = 6 months' history of erectile dysfunction, were randomized to two treatment arms for 12 weeks. One group (30 patients) received sildenafil (initial dose 50 mg taken 1 h before sexual activity for the first 2 weeks, increased to 100 mg or decreased to 25 mg, according to efficacy and/or tolerability). The remaining 30 patients received a matching placebo. Incidence and type of adverse effects were evaluated at 2, 4, 8 and 12 weeks. Nine patients (30.0%) on sildenafil (33.1% in the full ASSESS-I study) and one patient (3.3%) on placebo (22.8% in the full ASSESS-I study) experienced treatment-related adverse events, the most frequent being headache in the sildenafil group (reported by five patients [16.7%]; 11.0% in the full ASSESS-I study). Flushing, visual disturbance, dizziness, insomnia, myalgia and back pain each occurred in one patient in the sildenafil group (3.3%); in the placebo group, one patient (3.3%) had headache. Importantly, the incidence of cardiovascular and respiratory system adverse events were relatively less than in the full ASSESS-I population (cardiovascular 3.3% in the present study versus 10.2% in the full ASSESS-I population; respiratory 3.3% versus 5.5%). All adverse events were transient and mild, and did not lead to treatment withdrawal. There was no effect on sitting blood pressure, heart rate or standard laboratory parameters; more importantly, there was no incidence of myocardial infarction, stroke or priapism. These results should reassure Singaporean patients and their physicians of the safety of sildenafil for erectile dysfunction.
Fulltext Prostate-specific antigen levels among Chinese, Malays and Indians in Singapore from a community-based study

Chia SE, Lau WK, Cheng C, Chin CM, Tan J, Ho SH

Asian Pac J Cancer Prev, 2007 Jul-Sep;8(3):375-8.
PMID: 18159971

The purpose of this study was to examine the distribution of prostate-specific antigen levels among Chinese, Malays and Indians in Singapore, taking the effect of age into consideration. The study was carried out as part of the Singapore Prostate Awareness Week from 23-26th February 2004. Men above 50 years old went to four government-restructured hospitals to participate in the study. Participants filled up a questionnaire and provided 5 ml of blood for measurement of PSA levels using the Abbott IMx Total PSA assay (Abbott Laboratories). 3,486 men responded to the study, comprising 92.8% Chinese, 3.0% Malays, 2.5% Indians and 1.8% Others. 92.7% of them had PSA levels of 4 microg/L or less. There were no significant differences (p<0.05) between the mean PSA levels of Chinese (1.60 microg/L), Malays (1.39 microg/L), Indians (1.23 microg/L) and Others (1.70 microg/L). PSA levels were significantly associated with age (Spearman's r= 0.27, p<0.01). PSA levels increased with each 10-year age group and these trends were significant (p<0.0001) across both PSA group levels and age groupings. In the 50-60 years age groups, the prevalence of PSA levels >4 mug/L were 1.1% and 3.7% respectively. This rose rapidly to 11.3% and 23.5% for age groups >60-70 and >80 years respectively. Our study shows that the median PSA levels in the Caucasian population in the USA are higher than those of Chinese, Malays and Indians in Singapore. PSA levels were positively associated with age. It may be more appropriate to offer PSA testing to men who are >60 years old rather than the current >50 years.
Fulltext Carcinoma of stomach detected by routine transabdominal ultrasound

Wong M, Shum S, Chau W, Cheng C

Biomed Imaging Interv J, 2010 10 01;6(4):e39.
PMID: 21611075 DOI: 10.2349/biij.6.4.e39

Assessment of the stomach is not commonly included in routine scanning protocol of upper abdominal ultrasound (USG). However, assessment of the stomach in patients presenting with epigastric pain can yield invaluable results. This paper presents, as an illustration, a case of carcinoma of stomach detected by transabdominal ultrasound. The diagnosis is confirmed by subsequent CT, upper endoscopy and operation.
Fulltext Molecular relatedness of methicillin-resistant S. aureus isolates from staff, environment and pets at University Veterinary Hospital in Malaysia

Aklilu E, Zakaria Z, Hassan L, Hui Cheng C

PLoS One, 2012;7(8):e43329.
PMID: 22937034 DOI: 10.1371/journal.pone.0043329

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a problem in veterinary medicine and is no longer considered as a mere nosocomial pathogen. We studied the occurrence of MRSA in veterinary personnel, cats and dogs and the environmental premises in University Veterinary Hospital (UVH). We found the prevalence of MRSA as follows: UVH 2/28 (7.1%) staff, 8/100 (8%) of the pets [5/50 (10%) of the dogs and 3/50 (6%) of the cats)], and 9/28 (4.5%) of the environmental samples. Antibiotic sensitivity tests (AST) show multi-resistance characteristics of the MRSA and the minimum inhibitory concentration (MIC) values for the isolates ranged from 1.5 µg to >256 µg/ml. Molecular typing by using multi-locus sequence typing (MLST), staphylococcal protein A typing (spa typing) and pulsed-field gel electrophoresis (PFGE) was conducted and the results from MLST indicated that an isolate from a veterinary personnel (PG21), typed as ST1241 belonged to the same clonal complex (CC) as the two isolates from two dogs (DG16 and DG20), both being typed as ST59. The PFGE results revealed that the two isolates from two veterinary personnel, PG21 and PG16 belonged to closely related MRSA strains with isolates from dog (DG36) and from environmental surface (EV100) respectively. The fact that PFGE revealed close similarity between isolates from humans, a dog and environmental surfaces indicates the possibility for either of them to be the source of MRSA and the potential routes and risks of spread.
Sun exposure and the risk of prostate cancer in the Singapore Prostate Cancer Study: a case-control study

Chia SE, Wong KY, Cheng C, Lau W, Tan PH

Asian Pac J Cancer Prev, 2012;13(7):3179-85.
PMID: 22994730

BACKGROUND: Most of the epidemiology studies on the effects of sun exposure and prostate cancer were conducted among the temperate countries of North America and Europe. Little is known about the influence on Asian populations. The purpose of current study was to evaluate any association of sun exposure with risk of prostate cancer in Chinese, Malays and Indians who reside in the tropics.
METHODS: The Singapore Prostate Cancer Study is a hospital-based case-control study of 240 prostate cancer incident cases and 268 controls conducted in Singapore between April 2007 and May 2009. Detailed information on outdoor activities in the sun, skin colour, sun sensitivity and other possible risk factors were collected in personal interviews. Cases were further classified by Gleason scores and TNM staging. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression analysis, adjusted for age, ethnicity, education, family history of any cancers, BMI and skin colour.
RESULTS: We found that prostate cancer risk was increased in subjects with black/dark-brown eyes (OR 5.88, 95%CI 3.17-10.9), darker skin colour e.g. tan/dark brown/black (OR 7.62, 95%CI 3.41-17.0), frequent sunburn in lifetime (OR 4.30, 95%CI 1.7-11.2) and increased general sun exposure in adulthood per week (OR 2.03, 95%CI 1.09-3.81). The increased risk was consistent for high grade tumours and advanced stage prostate cancers.
CONCLUSION: The findings from this study suggest that excessive sun exposure is a risk factor for prostate cancer in Asians.
Epidemiology of internet behaviors and addiction among adolescents in six Asian countries

Mak KK, Lai CM, Watanabe H, Kim DI, Bahar N, Ramos M, et al.

Cyberpsychol Behav Soc Netw, 2014 Nov;17(11):720-8.
PMID: 25405785 DOI: 10.1089/cyber.2014.0139

Internet addiction has become a serious behavioral health problem in Asia. However, there are no up-to-date country comparisons. The Asian Adolescent Risk Behavior Survey (AARBS) screens and compares the prevalence of Internet behaviors and addiction in adolescents in six Asian countries. A total of 5,366 adolescents aged 12-18 years were recruited from six Asian countries: China, Hong Kong, Japan, South Korea, Malaysia, and the Philippines. Participants completed a structured questionnaire on their Internet use in the 2012-2013 school year. Internet addiction was assessed using the Internet Addiction Test (IAT) and the Revised Chen Internet Addiction Scale (CIAS-R). The variations in Internet behaviors and addiction across countries were examined. The overall prevalence of smartphone ownership is 62%, ranging from 41% in China to 84% in South Korea. Moreover, participation in online gaming ranges from 11% in China to 39% in Japan. Hong Kong has the highest number of adolescents reporting daily or above Internet use (68%). Internet addiction is highest in the Philippines, according to both the IAT (5%) and the CIAS-R (21%). Internet addictive behavior is common among adolescents in Asian countries. Problematic Internet use is prevalent and characterized by risky cyberbehaviors.
Fulltext Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model

Ude CC, Sulaiman SB, Min-Hwei N, Hui-Cheng C, Ahmad J, Yahaya NM, et al.

PLoS One, 2014;9(6):e98770.
PMID: 24911365 DOI: 10.1371/journal.pone.0098770

In this study, Adipose stem cells (ADSC) and bone marrow stem cells (BMSC), multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model.
The mediating role of Internet addiction in depression, social anxiety, and psychosocial well-being among adolescents in six Asian countries: a structural equation modelling approach

Lai CM, Mak KK, Watanabe H, Jeong J, Kim D, Bahar N, et al.

Public Health, 2015 Sep;129(9):1224-36.
PMID: 26343546 DOI: 10.1016/j.puhe.2015.07.031

OBJECTIVES: This study examines the associations of Internet addiction with social anxiety, depression, and psychosocial well-being among Asian adolescents. A self-medication model conceptualizing Internet addiction as a mediating role in relating depression and social anxiety to negative psychosocial well-being was tested.
STUDY DESIGN: A cross-sectional survey.
METHODS: In the Asian Adolescent Risk Behavior Survey (AARBS), 5366 adolescents aged 12-18 years from six Asian countries (China, Hong Kong, Japan, South Korea, Malaysia, and Philippines) completed a questionnaire with items of the Internet Addiction Test (IAT), Social Anxiety Scale for Adolescents (SAS-A), Center for Epidemiological Studies Depression Scale (CESD), Self-Rated Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA-SR) in the 2012-2013 school year. Structural equation modelling was used to examine the mediating role of Internet addiction in depression, social anxiety, and subjective psychosocial well-being.
RESULTS: Significant differences on the scores of IAT, SAS-A, CESD, and HoNOSCA-SR across the six countries were found. The proposed self-medication model of Internet addiction received satisfactory goodness-of-fit with data of all countries. After the path from social anxiety to Internet addiction had been discarded in the revised model, there was a significant improvement of the goodness-of-fit in the models for Japan, South Korea, and the Philippines.
CONCLUSIONS: Depression and social anxiety reciprocally influenced, whereas depression associated with poorer psychosocial well-being directly and indirectly through Internet addiction in all six countries. Internet addiction mediated the association between social anxiety and poor psychosocial well-being in China, Hong Kong, and Malaysia.
KEYWORDS: Adolescents; Asian; Depression; Internet addiction; Social anxiety; Structural equation modelling
Measurement Invariance of the Internet Addiction Test Among Hong Kong, Japanese, and Malaysian Adolescents

Lai CM, Mak KK, Cheng C, Watanabe H, Nomachi S, Bahar N, et al.

Cyberpsychol Behav Soc Netw, 2015 Oct;18(10):609-17.
PMID: 26468915 DOI: 10.1089/cyber.2015.0069

There has been increased research examining the psychometric properties on the Internet Addiction Test (IAT) in different populations. This population-based study examined the psychometric properties and measurement invariance of the IAT in adolescents from three Asian countries. In the Asian Adolescent Risk Behavior Survey (AARBS), 2,535 secondary school students (55.9% girls) aged 12-18 years from Hong Kong (n=844), Japan (n=744), and Malaysia (n=947) completed a survey in 2012-2013 school year. A nested hierarchy of hypotheses concerning the IAT cross-country invariance was tested using multigroup confirmatory factor analyses. Replicating past findings in Hong Kong adolescents, the construct of the IAT is best represented by a second-order three-factor structure in Malaysian and Japanese adolescents. Configural, metric, scalar, and partial strict factorial invariance was established across the three samples. No cross-country differences on Internet addiction were detected at the latent mean level. This study provided empirical support for the IAT as a reliable and factorially stable instrument, and valid to be used across Asian adolescent populations.
Fulltext Electroencephalographic changes associated with antinociceptive actions of lidocaine, ketamine, meloxicam, and morphine administration in minimally anaesthetized dogs

Kaka U, Hui Cheng C, Meng GY, Fakurazi S, Kaka A, Behan AA, et al.

Biomed Res Int, 2015;2015:305367.
PMID: 25695060 DOI: 10.1155/2015/305367

Effects of ketamine and lidocaine on electroencephalographic (EEG) changes were evaluated in minimally anaesthetized dogs, subjected to electric stimulus. Six dogs were subjected to six treatments in a crossover design with a washout period of one week. Dogs were subjected to intravenous boluses of lidocaine 2 mg/kg, ketamine 3 mg/kg, meloxicam 0.2 mg/kg, morphine 0.2 mg/kg and loading doses of lidocaine 2 mg/kg followed by continuous rate infusion (CRI) of 50 and 100 mcg/kg/min, and ketamine 3 mg/kg followed by CRI of 10 and 50 mcg/kg/min. Electroencephalogram was recorded during electrical stimulation prior to any drug treatment (before treatment) and during electrical stimulation following treatment with the drugs (after treatment) under anaesthesia. Anaesthesia was induced with propofol and maintained with halothane at a stable concentration between 0.85 and 0.95%. Pretreatment median frequency was evidently increased (P < 0.05) for all treatment groups. Lidocaine, ketamine, and morphine depressed the median frequency resulting from the posttreatment stimulation. The depression of median frequency suggested evident antinociceptive effects of these treatments in dogs. It is therefore concluded that lidocaine and ketamine can be used in the analgesic protocol for the postoperative pain management in dogs.
Automated extraction of retinal vasculature

Tan JH, Acharya UR, Chua KC, Cheng C, Laude A

Med Phys, 2016 May;43(5):2311.
PMID: 27147343 DOI: 10.1118/1.4945413

The authors propose an algorithm that automatically extracts retinal vasculature and provides a simple measure to correct the extraction. The output of the method is a network of salient points, and blood vessels are drawn by connecting the salient points using a centripetal parameterized Catmull-Rom spline.
Pregnancy and Dumping Syndrome post-bariatric surgery: a case report

Edawati DE, Abigail J, Mardiana K, Ming-Cheng C, Harris NS

Med J Malaysia, 2017 04;72(2):133-134.
PMID: 28473681 MyJurnal

This case report discusses dumping syndrome in the postbariatric mother. Diagnostically a challenge, the symptoms of postprandial hypoglycaemia mimic common early gestation complaints and may go undiagnosed, thus requiring a high index of suspicion. As weight-loss surgery gains traction, it is pertinent to note at booking and followups. The pregnancy is at-risk and multidisciplinary team management is central. The mainstay of management remains diet modification. There have been case reports of successful medical treatment of dumping syndrome in pregnancy with good maternal and fetal outcomes. However, more data is needed regarding the usage of these medical treatments in pregnancy.
Blood-based dynamic genomic signature for obsessive-compulsive disorder

Wang Y, Cheng C, Zhang Z, Wang J, Wang Y, Li X, et al.

Am J Med Genet B Neuropsychiatr Genet, 2018 12;177(8):709-716.
PMID: 30350918 DOI: 10.1002/ajmg.b.32675

No biologically based diagnostic criteria are in clinical use today for obsessive-compulsive disorder (OCD), schizophrenia, and major depressive disorder (MDD), which are defined with reference to Diagnostic and Statistical Manual clinical symptoms alone. However, these disorders cannot always be well distinguished on clinical grounds and may also be comorbid. A biological blood-based dynamic genomic signature that can differentiate among OCD, MDD, and schizophrenia would therefore be of great utility. This study enrolled 77 patients with OCD, 67 controls with no psychiatric illness, 39 patients with MDD, and 40 with schizophrenia. An OCD-specific gene signature was identified using blood gene expression analysis to construct a predictive model of OCD that can differentiate this disorder from healthy controls, MDD, and schizophrenia using a logistic regression algorithm. To verify that the genes selected were not derived as a result of chance, the algorithm was tested twice. First, the algorithm was used to predict the cohort with true disease/control status and second, the algorithm predicted the cohort with disease/control status randomly reassigned (null set). A six-gene panel (COPS7A, FKBP1A, FIBP, TP73-AS1, SDF4, and GOLGA8A) discriminated patients with OCD from healthy controls, MDD, and schizophrenia in the training set (with an area under the receiver-operating-characteristic curve of 0.938; accuracy, 86%; sensitivity, 88%; and specificity, 85%). Our findings indicate that a blood transcriptomic signature can distinguish OCD from healthy controls, MDD, and schizophrenia. This finding further confirms the feasibility of using dynamic blood-based genomic signatures in psychiatric disorders and may provide a useful tool for clinical staff engaged in OCD diagnosis and decision making.
First Evidence for cos2β>0 and Resolution of the Cabibbo-Kobayashi-Maskawa Quark-Mixing Unitarity Triangle Ambiguity

Adachi I, Adye T, Ahmed H, Ahn JK, Aihara H, Akar S, et al.

Phys Rev Lett, 2018 Dec 28;121(26):261801.
PMID: 30636113 DOI: 10.1103/PhysRevLett.121.261801

We present first evidence that the cosine of the CP-violating weak phase 2β is positive, and hence exclude trigonometric multifold solutions of the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle using a time-dependent Dalitz plot analysis of B^{0}→D^{(*)}h^{0} with D→K_{S}^{0}π^{+}π^{-} decays, where h^{0}∈{π^{0},η,ω} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the ϒ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6}BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6}BB[over ¯] pairs recorded by the Belle detector. The results of the measurement are sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle β of the CKM Unitarity Triangle is β=[22.5±4.4(stat)±1.2(syst)±0.6(model)]°. The measurement assumes no direct CP violation in B^{0}→D^{(*)}h^{0} decays. The quoted model uncertainties are due to the composition of the D^{0}→K_{S}^{0}π^{+}π^{-} decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a high-statistics e^{+}e^{-}→cc[over ¯] data sample. CP violation is observed in B^{0}→D^{(*)}h^{0} decays at the level of 5.1 standard deviations. The significance for cos2β>0 is 3.7 standard deviations. The trigonometric multifold solution π/2-β=(68.1±0.7)° is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle.
Fulltext Asthma control and asthma treatment adherence in primary care: results from the prospective, multicentre, non-interventional, observational cohort ASCOPE study in Malaysia

Mohd Isa NA, Cheng CL, Nasir NH, Naidu V, Gopal VR, Alexander AK

Med J Malaysia, 2020 07;75(4):331-337.
PMID: 32723990

INTRODUCTION: As the first point of contact for those presenting with asthma symptoms, primary healthcare plays a crucial role in asthma management. This is a nationwide study of assessment of asthma symptom control and adherence to asthma medication among outpatients in public health clinics in Malaysia.

METHODS: This is a prospective, observational multicentre study (ASCOPE; NCT03804632). Data on asthma control, assessment of control symptoms, and adherence to treatment were collected from medical records and interviews of patients. The level of asthma control was assessed using the Global Initiative for Asthma (GINA) Assessment of Symptom Control. Adherence of patient to medication for asthma was assessed through interview of patients using four questions adapted from the Malaysian Medication Adherence Scale.

RESULTS: Among the 1011 patients recruited, 416 (41%) had well controlled asthma, 388 (38%) were partly controlled, and 207 (21%) had uncontrolled asthma. Majority (81%) had mild asthma and all patients were on asthma medication. Most patients did not have spirometry data (97%) but underwent peak flow rate measurements (98%). Poor adherence occurred at all levels of asthma control but was worst among those with uncontrolled asthma. This was statistically significant across all four questions on adherence (p<0.05). For example, more patients with uncontrolled asthma forgot doses (56%) or stopped treatment (39%) than those with well-controlled asthma (44% and 27%respectively).

CONCLUSIONS: Among Malaysian primary care patients with asthma, less than 50% had well-controlled asthma, and low adherence to treatment was common. More effort is needed to improve asthma control among patients in Malaysia, including those with mild asthma.
Observation of a New Excited Beauty Strange Baryon Decaying to Ξ_{b}^{-}π^{+}π^{-}

Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.

Phys Rev Lett, 2021 Jun 25;126(25):252003.
PMID: 34241504 DOI: 10.1103/PhysRevLett.126.252003

The Ξ_{b}^{-}π^{+}π^{-} invariant mass spectrum is investigated with an event sample of proton-proton collisions at sqrt[s]=13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140 fb^{-1}. The ground state Ξ_{b}^{-} is reconstructed via its decays to J/ψΞ^{-} and J/ψΛK^{-}. A narrow resonance, labeled Ξ_{b}(6100)^{-}, is observed at a Ξ_{b}^{-}π^{+}π^{-} invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξ_{b}^{-}) MeV, where the last uncertainty reflects the precision of the Ξ_{b}^{-} baryon mass. The upper limit on the Ξ_{b}(6100)^{-} natural width is determined to be 1.9 MeV at 95% confidence level. The low Ξ_{b}(6100)^{-} signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξ_{c} baryon states, the new Ξ_{b}(6100)^{-} resonance and its decay sequence are consistent with the orbitally excited Ξ_{b}^{-} baryon, with spin and parity quantum numbers J^{P}=3/2^{-}.
Induction of periodontal disease via retentive ligature, lipopolysaccharide injection, and their combination in a rat model

Mustafa H, Cheng CH, Radzi R, Fong LS, Mustapha NM, Dyary HO

Pol J Vet Sci, 2021 Sep;24(3):365-373.
PMID: 34730299 DOI: 10.24425/pjvs.2021.138727

Periodontitis is a highly prevalent, chronic immune-inflammatory disease of the periodontium that results in the periodontium and alveolar bone loss's progressive destruction. In this study, the induction of periodontal disease via retentive ligature, lipopolysaccharide, and their combination at three different times were compared in a rat model. Seventy-two Sprague Dawley rats were distributed into four treatment groups: 1) control group with no treatment; 2) application of 4/0 nylon ligature around second maxillary molars; 3) combination of ligature and LPS injection (ligature-LPS); 4) intragingival injection of Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) to the palatal mucosa of the second maxillary molars. Six rats were sacrificed from each group after 7, 14, and 30 days of periodontal disease induction. Alveolar bone loss, attachment loss, number of inflammatory cells, and blood vessels were evaluated histologically. A micro-CT scan was used as a parameter to know the rate of alveolar bone loss. Parametric data were analyzed using two-way ANOVA followed by Bonferroni correction with a significance set at 5%. Non-parametric data were analyzed using Kruskal-Wallis, followed by multiple comparisons with Bonferroni correction. The histological results revealed significant destructive changes in the periodontal tissues and alveolar bone following the ligature and ligature-LPS induction techniques. These changes were evident as early as seven days, maintained until 14 days post-treatment, and declined with time. The ligature technique was effective in inducing acute periodontal disease. The LPS injection technique did not induce alveolar bone loss, and its combination to ligature added insignificant effects.
Biomimetic self-assembly of lipase-zeolitic imidazolate frameworks with enhanced biosensing of protox inhibiting herbicides

Cheng C, Shen C, Lai OM, Tan CP, Cheong LZ

Anal Methods, 2021 Nov 04;13(42):4974-4984.
PMID: 34661208 DOI: 10.1039/d1ay01307f

Protox inhibiting herbicides such as nitrofen have detrimental effects on the environment and human health. The current work aims to fabricate a Candida rugosa lipase (CRL)-based electrochemical sensor for rapid and sensitive detection of protox inhibiting herbicides (nitrofen). We proposed the use of poly(vinylpyrrolidone) (PVP) and amino-acids to promote accumulation of Zn2+ ions at the surfaces of Candida rugosa lipase (CRL) and subsequently induce self-assembly of a CRL-zeolitic imidazolate framework (ZIF) structure. This process can be easily and rapidly achieved via a one-pot facile self-assembly method. Steady-state fluorescence spectroscopy indicated that CRL has undergone a conformational change following encapsulation within the ZIF structure. This conformational change is beneficial as the prepared PVP/Glu/CRL@ZIF-8 exhibited enhanced catalytic activity (207% of native CRL), and higher substrate affinity (lower Km than native CRL) and showed high stability under harsh denaturing conditions. PVP/Glu/CRL@ZIF-8 was finally used for electrochemical biosensing of nitrofen. The fabricated biosensor has a wide linear detection range (0-100 μM), a lower limit of detection and a good recovery rate.
Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at sqrt[s]=5.02 TeV Using Leptonic Decays

Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Dragicevic M, et al.

Phys Rev Lett, 2021 Nov 05;127(19):191801.
PMID: 34797136 DOI: 10.1103/PhysRevLett.127.191801

The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst) pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst) pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.

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