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Fulltext Identification of ten variants associated with risk of estrogen-receptor-negative breast cancer

Milne RL, Kuchenbaecker KB, Michailidou K, Beesley J, Kar S, Lindström S, et al.

Nat Genet, 2017 Dec;49(12):1767-1778.
PMID: 29058716 DOI: 10.1038/ng.3785

Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414 with breast cancer), all of European origin. We identified independent associations at P < 5 × 10-8 with ten variants at nine new loci. At P < 0.05, we replicated associations with 10 of 11 variants previously reported in ER-negative disease or BRCA1 mutation carrier GWAS and observed consistent associations with ER-negative disease for 105 susceptibility variants identified by other studies. These 125 variants explain approximately 16% of the familial risk of this breast cancer subtype. There was high genetic correlation (0.72) between risk of ER-negative breast cancer and breast cancer risk for BRCA1 mutation carriers. These findings may lead to improved risk prediction and inform further fine-mapping and functional work to better understand the biological basis of ER-negative breast cancer.
Fulltext Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer

Phelan CM, Kuchenbaecker KB, Tyrer JP, Kar SP, Lawrenson K, Winham SJ, et al.

Nat Genet, 2017 May;49(5):680-691.
PMID: 28346442 DOI: 10.1038/ng.3826

To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC.
Fulltext Fine-mapping of 150 breast cancer risk regions identifies 191 likely target genes

Fachal L, Aschard H, Beesley J, Barnes DR, Allen J, Kar S, et al.

Nat Genet, 2020 01;52(1):56-73.
PMID: 31911677 DOI: 10.1038/s41588-019-0537-1

Genome-wide association studies have identified breast cancer risk variants in over 150 genomic regions, but the mechanisms underlying risk remain largely unknown. These regions were explored by combining association analysis with in silico genomic feature annotations. We defined 205 independent risk-associated signals with the set of credible causal variants in each one. In parallel, we used a Bayesian approach (PAINTOR) that combines genetic association, linkage disequilibrium and enriched genomic features to determine variants with high posterior probabilities of being causal. Potentially causal variants were significantly over-represented in active gene regulatory regions and transcription factor binding sites. We applied our INQUSIT pipeline for prioritizing genes as targets of those potentially causal variants, using gene expression (expression quantitative trait loci), chromatin interaction and functional annotations. Known cancer drivers, transcription factors and genes in the developmental, apoptosis, immune system and DNA integrity checkpoint gene ontology pathways were over-represented among the highest-confidence target genes.
Polygenic risk modeling for prediction of epithelial ovarian cancer risk

Dareng EO, Tyrer JP, Barnes DR, Jones MR, Yang X, Aben KKH, et al.

Eur J Hum Genet, 2022 Jan 14.
PMID: 35027648 DOI: 10.1038/s41431-021-00987-7

Polygenic risk scores (PRS) for epithelial ovarian cancer (EOC) have the potential to improve risk stratification. Joint estimation of Single Nucleotide Polymorphism (SNP) effects in models could improve predictive performance over standard approaches of PRS construction. Here, we implemented computationally efficient, penalized, logistic regression models (lasso, elastic net, stepwise) to individual level genotype data and a Bayesian framework with continuous shrinkage, "select and shrink for summary statistics" (S4), to summary level data for epithelial non-mucinous ovarian cancer risk prediction. We developed the models in a dataset consisting of 23,564 non-mucinous EOC cases and 40,138 controls participating in the Ovarian Cancer Association Consortium (OCAC) and validated the best models in three populations of different ancestries: prospective data from 198,101 women of European ancestries; 7,669 women of East Asian ancestries; 1,072 women of African ancestries, and in 18,915 BRCA1 and 12,337 BRCA2 pathogenic variant carriers of European ancestries. In the external validation data, the model with the strongest association for non-mucinous EOC risk derived from the OCAC model development data was the S4 model (27,240 SNPs) with odds ratios (OR) of 1.38 (95% CI: 1.28-1.48, AUC: 0.588) per unit standard deviation, in women of European ancestries; 1.14 (95% CI: 1.08-1.19, AUC: 0.538) in women of East Asian ancestries; 1.38 (95% CI: 1.21-1.58, AUC: 0.593) in women of African ancestries; hazard ratios of 1.36 (95% CI: 1.29-1.43, AUC: 0.592) in BRCA1 pathogenic variant carriers and 1.49 (95% CI: 1.35-1.64, AUC: 0.624) in BRCA2 pathogenic variant carriers. Incorporation of the S4 PRS in risk prediction models for ovarian cancer may have clinical utility in ovarian cancer prevention programs.
Fulltext Correction: Polygenic risk modeling for prediction of epithelial ovarian cancer risk

Dareng EO, Tyrer JP, Barnes DR, Jones MR, Yang X, Aben KKH, et al.

Eur J Hum Genet, 2022 May;30(5):630-631.
PMID: 35314806 DOI: 10.1038/s41431-022-01085-y
Fulltext Association of Genomic Domains in BRCA1 and BRCA2 with Prostate Cancer Risk and Aggressiveness

Patel VL, Busch EL, Friebel TM, Cronin A, Leslie G, McGuffog L, et al.

Cancer Res, 2020 Feb 01;80(3):624-638.
PMID: 31723001 DOI: 10.1158/0008-5472.CAN-19-1840

Pathogenic sequence variants (PSV) in BRCA1 or BRCA2 (BRCA1/2) are associated with increased risk and severity of prostate cancer. We evaluated whether PSVs in BRCA1/2 were associated with risk of overall prostate cancer or high grade (Gleason 8+) prostate cancer using an international sample of 65 BRCA1 and 171 BRCA2 male PSV carriers with prostate cancer, and 3,388 BRCA1 and 2,880 BRCA2 male PSV carriers without prostate cancer. PSVs in the 3' region of BRCA2 (c.7914+) were significantly associated with elevated risk of prostate cancer compared with reference bin c.1001-c.7913 [HR = 1.78; 95% confidence interval (CI), 1.25-2.52; P = 0.001], as well as elevated risk of Gleason 8+ prostate cancer (HR = 3.11; 95% CI, 1.63-5.95; P = 0.001). c.756-c.1000 was also associated with elevated prostate cancer risk (HR = 2.83; 95% CI, 1.71-4.68; P = 0.00004) and elevated risk of Gleason 8+ prostate cancer (HR = 4.95; 95% CI, 2.12-11.54; P = 0.0002). No genotype-phenotype associations were detected for PSVs in BRCA1. These results demonstrate that specific BRCA2 PSVs may be associated with elevated risk of developing aggressive prostate cancer. SIGNIFICANCE: Aggressive prostate cancer risk in BRCA2 mutation carriers may vary according to the specific BRCA2 mutation inherited by the at-risk individual.
Fulltext Mutational spectrum in a worldwide study of 29,700 families with BRCA1 or BRCA2 mutations

Rebbeck TR, Friebel TM, Friedman E, Hamann U, Huo D, Kwong A, et al.

Hum Mutat, 2018 05;39(5):593-620.
PMID: 29446198 DOI: 10.1002/humu.23406

The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database. We observed substantial variation in mutation type and frequency by geographical region and race/ethnicity. In addition to known founder mutations, mutations of relatively high frequency were identified in specific racial/ethnic or geographic groups that may reflect founder mutations and which could be used in targeted (panel) first pass genotyping for specific populations. Knowledge of the population-specific mutational spectrum in BRCA1 and BRCA2 could inform efficient strategies for genetic testing and may justify a more broad-based oncogenetic testing in some populations.
Fulltext Polygenic risk scores and breast and epithelial ovarian cancer risks for carriers of BRCA1 and BRCA2 pathogenic variants

Barnes DR, Rookus MA, McGuffog L, Leslie G, Mooij TM, Dennis J, et al.

Genet Med, 2020 10;22(10):1653-1666.
PMID: 32665703 DOI: 10.1038/s41436-020-0862-x

PURPOSE: We assessed the associations between population-based polygenic risk scores (PRS) for breast (BC) or epithelial ovarian cancer (EOC) with cancer risks for BRCA1 and BRCA2 pathogenic variant carriers.
METHODS: Retrospective cohort data on 18,935 BRCA1 and 12,339 BRCA2 female pathogenic variant carriers of European ancestry were available. Three versions of a 313 single-nucleotide polymorphism (SNP) BC PRS were evaluated based on whether they predict overall, estrogen receptor (ER)-negative, or ER-positive BC, and two PRS for overall or high-grade serous EOC. Associations were validated in a prospective cohort.
RESULTS: The ER-negative PRS showed the strongest association with BC risk for BRCA1 carriers (hazard ratio [HR] per standard deviation = 1.29 [95% CI 1.25-1.33], P = 3×10-72). For BRCA2, the strongest association was with overall BC PRS (HR = 1.31 [95% CI 1.27-1.36], P = 7×10-50). HR estimates decreased significantly with age and there was evidence for differences in associations by predicted variant effects on protein expression. The HR estimates were smaller than general population estimates. The high-grade serous PRS yielded the strongest associations with EOC risk for BRCA1 (HR = 1.32 [95% CI 1.25-1.40], P = 3×10-22) and BRCA2 (HR = 1.44 [95% CI 1.30-1.60], P = 4×10-12) carriers. The associations in the prospective cohort were similar.
CONCLUSION: Population-based PRS are strongly associated with BC and EOC risks for BRCA1/2 carriers and predict substantial absolute risk differences for women at PRS distribution extremes.
Fulltext Copy number variants as modifiers of breast cancer risk for BRCA1/BRCA2 pathogenic variant carriers

Hakkaart C, Pearson JF, Marquart L, Dennis J, Wiggins GAR, Barnes DR, et al.

Commun Biol, 2022 Oct 06;5(1):1061.
PMID: 36203093 DOI: 10.1038/s42003-022-03978-6

The contribution of germline copy number variants (CNVs) to risk of developing cancer in individuals with pathogenic BRCA1 or BRCA2 variants remains relatively unknown. We conducted the largest genome-wide analysis of CNVs in 15,342 BRCA1 and 10,740 BRCA2 pathogenic variant carriers. We used these results to prioritise a candidate breast cancer risk-modifier gene for laboratory analysis and biological validation. Notably, the HR for deletions in BRCA1 suggested an elevated breast cancer risk estimate (hazard ratio (HR) = 1.21), 95% confidence interval (95% CI = 1.09-1.35) compared with non-CNV pathogenic variants. In contrast, deletions overlapping SULT1A1 suggested a decreased breast cancer risk (HR = 0.73, 95% CI 0.59-0.91) in BRCA1 pathogenic variant carriers. Functional analyses of SULT1A1 showed that reduced mRNA expression in pathogenic BRCA1 variant cells was associated with reduced cellular proliferation and reduced DNA damage after treatment with DNA damaging agents. These data provide evidence that deleterious variants in BRCA1 plus SULT1A1 deletions contribute to variable breast cancer risk in BRCA1 carriers.
Fulltext Prediction of Breast and Prostate Cancer Risks in Male BRCA1 and BRCA2 Mutation Carriers Using Polygenic Risk Scores

Lecarpentier J, Silvestri V, Kuchenbaecker KB, Barrowdale D, Dennis J, McGuffog L, et al.

J Clin Oncol, 2017 Jul 10;35(20):2240-2250.
PMID: 28448241 DOI: 10.1200/JCO.2016.69.4935

Purpose BRCA1/2 mutations increase the risk of breast and prostate cancer in men. Common genetic variants modify cancer risks for female carriers of BRCA1/2 mutations. We investigated-for the first time to our knowledge-associations of common genetic variants with breast and prostate cancer risks for male carriers of BRCA1/ 2 mutations and implications for cancer risk prediction. Materials and Methods We genotyped 1,802 male carriers of BRCA1/2 mutations from the Consortium of Investigators of Modifiers of BRCA1/2 by using the custom Illumina OncoArray. We investigated the combined effects of established breast and prostate cancer susceptibility variants on cancer risks for male carriers of BRCA1/2 mutations by constructing weighted polygenic risk scores (PRSs) using published effect estimates as weights. Results In male carriers of BRCA1/2 mutations, PRS that was based on 88 female breast cancer susceptibility variants was associated with breast cancer risk (odds ratio per standard deviation of PRS, 1.36; 95% CI, 1.19 to 1.56; P = 8.6 × 10-6). Similarly, PRS that was based on 103 prostate cancer susceptibility variants was associated with prostate cancer risk (odds ratio per SD of PRS, 1.56; 95% CI, 1.35 to 1.81; P = 3.2 × 10-9). Large differences in absolute cancer risks were observed at the extremes of the PRS distribution. For example, prostate cancer risk by age 80 years at the 5th and 95th percentiles of the PRS varies from 7% to 26% for carriers of BRCA1 mutations and from 19% to 61% for carriers of BRCA2 mutations, respectively. Conclusion PRSs may provide informative cancer risk stratification for male carriers of BRCA1/2 mutations that might enable these men and their physicians to make informed decisions on the type and timing of breast and prostate cancer risk management.
Fulltext Characterization of the Cancer Spectrum in Men With Germline BRCA1 and BRCA2 Pathogenic Variants: Results From the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

Silvestri V, Leslie G, Barnes DR, CIMBA Group, Agnarsson BA, Aittomäki K, et al.

JAMA Oncol, 2020 Aug 01;6(8):1218-1230.
PMID: 32614418 DOI: 10.1001/jamaoncol.2020.2134

IMPORTANCE: The limited data on cancer phenotypes in men with germline BRCA1 and BRCA2 pathogenic variants (PVs) have hampered the development of evidence-based recommendations for early cancer detection and risk reduction in this population.
OBJECTIVE: To compare the cancer spectrum and frequencies between male BRCA1 and BRCA2 PV carriers.
DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of 6902 men, including 3651 BRCA1 and 3251 BRCA2 PV carriers, older than 18 years recruited from cancer genetics clinics from 1966 to 2017 by 53 study groups in 33 countries worldwide collaborating through the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Clinical data and pathologic characteristics were collected.
MAIN OUTCOMES AND MEASURES: BRCA1/2 status was the outcome in a logistic regression, and cancer diagnoses were the independent predictors. All odds ratios (ORs) were adjusted for age, country of origin, and calendar year of the first interview.
RESULTS: Among the 6902 men in the study (median [range] age, 51.6 [18-100] years), 1634 cancers were diagnosed in 1376 men (19.9%), the majority (922 of 1,376 [67%]) being BRCA2 PV carriers. Being affected by any cancer was associated with a higher probability of being a BRCA2, rather than a BRCA1, PV carrier (OR, 3.23; 95% CI, 2.81-3.70; P
Fulltext The predictive ability of the 313 variant-based polygenic risk score for contralateral breast cancer risk prediction in women of European ancestry with a heterozygous BRCA1 or BRCA2 pathogenic variant

Lakeman IMM, van den Broek AJ, Vos JAM, Barnes DR, Adlard J, Andrulis IL, et al.

Genet Med, 2021 Sep;23(9):1726-1737.
PMID: 34113011 DOI: 10.1038/s41436-021-01198-7

PURPOSE: To evaluate the association between a previously published 313 variant-based breast cancer (BC) polygenic risk score (PRS313) and contralateral breast cancer (CBC) risk, in BRCA1 and BRCA2 pathogenic variant heterozygotes.
METHODS: We included women of European ancestry with a prevalent first primary invasive BC (BRCA1 = 6,591 with 1,402 prevalent CBC cases; BRCA2 = 4,208 with 647 prevalent CBC cases) from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), a large international retrospective series. Cox regression analysis was performed to assess the association between overall and ER-specific PRS313 and CBC risk.
RESULTS: For BRCA1 heterozygotes the estrogen receptor (ER)-negative PRS313 showed the largest association with CBC risk, hazard ratio (HR) per SD = 1.12, 95% confidence interval (CI) (1.06-1.18), C-index = 0.53; for BRCA2 heterozygotes, this was the ER-positive PRS313, HR = 1.15, 95% CI (1.07-1.25), C-index = 0.57. Adjusting for family history, age at diagnosis, treatment, or pathological characteristics for the first BC did not change association effect sizes. For women developing first BC
Perspectives and advancements in the design of nanomaterials for targeted cancer theranostics

Tan YY, Yap PK, Xin Lim GL, Mehta M, Chan Y, Ng SW, et al.

Chem Biol Interact, 2020 Sep 25;329:109221.
PMID: 32768398 DOI: 10.1016/j.cbi.2020.109221

Cancer continues to be one of the most challenging diseases to be treated and is one of the leading causes of deaths around the globe. Cancers account for 13% of all deaths each year, with cancer-related mortality expected to rise to 13.1 million by the year 2030. Although, we now have a large library of chemotherapeutic agents, the problem of non-selectivity remains the biggest drawback, as these substances are toxic not only to cancerous cells, but also to other healthy cells in the body. The limitations with chemotherapy and radiation have led to the discovery and development of novel strategies for safe and effective treatment strategies to manage the menace of cancer. Researchers have long justified and have shed light on the emergence of nanotechnology as a potential area for cancer therapy and diagnostics, whereby, nanomaterials are used primarily as nanocarriers or as delivery agents for anticancer drugs due to their tumor targeting properties. Furthermore, nanocarriers loaded with chemotherapeutic agents also overcome biological barriers such as renal and hepatic clearances, thus improving therapeutic efficacy with lowered morbidity. Theranostics, which is the combination of rationally designed nanomaterials with cancer-targeting moieties, along with protective polymers and imaging agents has become one of the core keywords in cancer research. In this review, we have highlighted the potential of various nanomaterials for their application in cancer therapy and imaging, including their current state and clinical prospects. Theranostics has successfully paved a path to a new era of drug design and development, in which nanomaterials and imaging contribute to a large variety of cancer therapies and provide a promising future in the effective management of various cancers. However, in order to meet the therapeutic needs, theranostic nanomaterials must be designed in such a way, that take into account the pharmacokinetic and pharmacodynamics properties of the drug for the development of effective carcinogenic therapy.
Fulltext Fine-needle aspiration to improve diagnosis of melioidosis of the head and neck in children: a study from Sarawak, Malaysia

Mohan A, Podin Y, Liew DW, Mahendra Kumar J, Lau PS, Tan YY, et al.

BMC Infect Dis, 2021 Oct 15;21(1):1069.
PMID: 34654392 DOI: 10.1186/s12879-021-06754-9

BACKGROUND: Melioidosis, the infection caused by Burkholderia pseudomallei, is associated with a high case fatality rate, due in part to difficulties in clinical recognition and diagnostic confirmation of the disease. Although head and neck involvement is common in children, specific disease manifestations differ between geographic regions. The aim of this study was to provide a detailed description of melioidosis of the head and neck among children in Sarawak, Malaysia, and determine if fine-needle aspiration of suspected head or neck lesions could improve melioidosis diagnosis.
METHODS: We conducted a retrospective descriptive study of all children aged
Prognostic factors in patients with non-small cell lung carcinoma and brain metastases: a Malaysian perspective

Tang WH, Alip A, Saad M, Phua VC, Chandran H, Tan YH, et al.

Asian Pac J Cancer Prev, 2015;16(5):1901-6.
PMID: 25773842

BACKGROUND: Brain metastases occur in about 20-40% of patients with non-small-cell lung carcinoma (NSCLC), and are usually associated with a poor outcome. Whole brain radiotherapy (WBRT) is widely used but increasingly, more aggressive local treatments such as surgery or stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) are being employed. In our study we aimed to describe the various factors affecting outcomes in NSCLC patients receiving local therapy for brain metastases.
MATERIALS AND METHODS: The case records of 125 patients with NSCLC and brain metastases consecutively treated with radiotherapy at two tertiary centres from January 2006 to June 2012 were analysed for patient, tumour and treatment-related prognostic factors. Patients receiving SRS/SRT were treated using Cyberknife. Variables were examined in univariate and multivariate testing.
RESULTS: Overall median survival was 3.4 months (95%CI: 1.7-5.1). Median survival for patients with multiple metastases receiving WBRT was 1.5 months, 1-3 metastases receiving WBRT was 3.6 months and 1-3 metastases receiving surgery or SRS/SRT was 8.9 months. ECOG score (≤2 vs >2, p=0.001), presence of seizure (yes versus no, p=0.031), treatment modality according to number of brain metastases (1-3 metastases+surgery or SRS/SRT±WBRT vs 1-3 metastases+WBRT only vs multiple metastases+WBRT only, p=0.007) and the use of post-therapy systemic treatment (yes versus no, p=0.001) emerged as significant on univariate analysis. All four factors remained statistically significant on multivariate analysis.
CONCLUSIONS: ECOG ≤2, presence of seizures, oligometastatic disease treated with aggressive local therapy (surgery or SRS/SRT) and the use of post-therapy systemic treatment are favourable prognostic factors in NSCLC patients with brain metastases.
Demographics and outcome of patients with congenital haemophilia in Sarawak, Malaysia

Tang ASO, Wong QY, Tan YY, Chieng CH, Ko CT, Ong GB, et al.

Med J Malaysia, 2021 Jan;76(1):51-55.
PMID: 33510109

INTRODUCTION: Sarawak has a population that is geographically and characteristically widely varied. This study aimed to determine the demographic profile of patients in Sarawak, Malaysia. Materials and Methods - A cross-sectional study was conducted in 2019 at four major haemophilia treatment centres in Kuching, Sibu, Bintulu and Miri Hospitals, Sarawak. Demographic and clinical data were collected with consents from patients.
RESULTS AND DISCUSSION: Ninety-six haemophilia patients were identified - 79(82.3%) haemophilia A(HA) and 17(17.7%) haemophilia B(HB). Severe haemophilia patients were noted in 45.6% (36/79) of HA and 64.7% (11/17) of HB. In all 44.3% of the HA and 52.9% of the HB population had no identifiable family history of haemophilia. Two-thirds of the patients with severe HA were on prophylaxis [24/36 (66.7%)] and only onethird [4/11 (36.4%)] in severe HB. Inhibitors developed in 9/79 (11.4%) of the HA population [3/79 (3.8%) high responders]. The median inhibitor titre was not significantly different between the different treatment groups - on demand versus prophylaxis (1.0BU versus 2.0BU; z statistic -1.043, p-value 0.297, Mann-Whitney test). None of the patients developed inhibitory alloantibodies to factor IX. Four HA patients (5.1%) underwent immune tolerance induction where one case had a successful outcome. Three severe HA patients received emicizumab prophylaxis and showed remarkable reduction in bleeding events with no thromboembolic events being reported. One female moderate HA patient received PEGylated recombinant anti-haemophilic factor. Eleven patients underwent radiosynovectomy. One mild HB patient succumbed to traumatic intracranial bleeding. Our data reported a prevalence (per 100,000 males) of 5.40 cases for all severities of HA, 2.46 cases for severe HA; 1.16 cases for all severities of HB, and 0.75 cases for severe HB. The overall incidence of HA and HB was 1 in 11,500 and 1 in 46,000, respectively.
CONCLUSION: This study outlines the Sarawakian haemophilia landscape and offers objective standards for forward planning. Shared responsibilities among all parties are of utmost importance to improve the care of our haemophilia population.
Antiretroviral agents in pre-exposure prophylaxis: emerging and advanced trends in HIV prevention

Yap PK, Loo Xin GL, Tan YY, Chellian J, Gupta G, Liew YK, et al.

J Pharm Pharmacol, 2019 Sep;71(9):1339-1352.
PMID: 31144296 DOI: 10.1111/jphp.13107

OBJECTIVES: Antiretroviral agents (ARVs) have been the most promising line of therapy in the management of human immunodeficiency virus (HIV) infections. Some of these ARVs are used in the pre-exposure prophylaxis (PrEP) to suppress the transmission of HIV. Prophylaxis is primarily used in uninfected people, before exposure, to effectively prevent HIV infection. Several studies have shown that ART PrEP prevents HIV acquisition from sexual, blood and mother-to-child transmissions. However, there are also several challenges and limitations to PrEP. This review focuses on the current antiretroviral therapies used in PrEP.
KEY FINDINGS: Among ARVs, the most common drugs employed from the class of entry inhibitors are maraviroc (MVC), which is a CCR5 receptor antagonist. Other entry inhibitors like emtricitabine (FTC) and tenofovir (TFV) are also used. Rilpivirine (RPV) and dapivirine (DPV) are the most common drugs employed from the Non-nucleoside reverse transcriptase inhibitor (NNRTIs) class, whereas, tenofovir disoproxil fumarate (TDF) is primarily used in the Nucleoside Reverse Transcriptase Inhibitor (NRTIs) class. Cabotegravir (CAB) is an analog of dolutegravir, and it is an integrase inhibitor. Some of these drugs are also used in combination with other drugs from the same class.
SUMMARY: Some of the most common pre-exposure prophylactic strategies employed currently are the use of inhibitors, namely entry inhibitors, non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, integrase and protease inhibitors. In addition, we have also discussed on the adverse effects caused by ART in PrEP, pharmacoeconomics factors and the use of antiretroviral prophylaxis in serodiscordant couples.
Fulltext Development and Evaluation of Topical Zinc Oxide Nanogels Formulation Using Dendrobium anosmum and Its Effect on Acne Vulgaris

Tan YY, Wong LS, Nyam KL, Wittayanarakul K, Zawawi NA, Rajendran K, et al.

Molecules, 2023 Sep 22;28(19).
PMID: 37836592 DOI: 10.3390/molecules28196749

Zinc oxide nanoparticles have high levels of biocompatibility, a low impact on environmental contamination, and suitable to be used as an ingredient for environmentally friendly skincare products. In this study, biogenically synthesized zinc oxide nanoparticles using Dendrobium anosum are used as a reducing and capping agent for topical anti-acne nanogels, and the antimicrobial effect of the nanogel is assessed on Cutibacterium acne and Staphylococcus aureus. Dendrobium anosmum leaf extract was examined for the presence of secondary metabolites and its total amount of phenolic and flavonoid content was determined. Both the biogenically and chemogenic-synthesized zinc oxide nanoparticles were compared using UV-Visible spectrophotometer, FE-SEM, XRD, and FTIR. To produce the topical nanogel, the biogenic and chemogenic zinc oxide nanoparticles were mixed with a carbomer and hydroxypropyl-methyl cellulose (HPMC) polymer. The mixtures were then tested for physical and chemical characteristics. To assess their anti-acne effectiveness, the mixtures were tested against C. acne and S. aureus. The biogenic zinc oxide nanoparticles have particle sizes of 20 nm and a high-phase purity. In comparison to chemogenic nanoparticles, the hydrogels with biogenically synthesized nanoparticles was more effective against Gram-positive bacteria. Through this study, the hybrid nanogels was proven to be effective against the microbes that cause acne and to be potentially used as a green product against skin infections.
Fulltext Reducing scanning electron microscope charging by using exponential contrast stretching technique on post-processing images

Sim KS, Tan YY, Lai MA, Tso CP, Lim WK

J Microsc, 2010 Apr 1;238(1):44-56.
PMID: 20384837 DOI: 10.1111/j.1365-2818.2009.03328.x

An exponential contrast stretching (ECS) technique is developed to reduce the charging effects on scanning electron microscope images. Compared to some of the conventional histogram equalization methods, such as bi-histogram equalization and recursive mean-separate histogram equalization, the proposed ECS method yields better image compensation. Diode sample chips with insulating and conductive surfaces are used as test samples to evaluate the efficiency of the developed algorithm. The algorithm is implemented in software with a frame grabber card, forming the front-end video capture element.
Diffuse axonal injury A clinical and computerised tomography study of 128 patients

Selladurai BM, Sherazi ZA, Nair RC, Tan YY, Khadar MA

J Clin Neurosci, 1995 Jul;2(3):216-23.
PMID: 18638817

A study of clinical, computerised tomography (CT) profile and outcome was made of 128 patients, diagnosed to have diffuse axonal injury based on CT criteria. The mean age was 26 years. A lucid interval was present in 37 patients and hypoxia and/or hypotension was present in 43 patients. The depth of "marker lesions" in CT correlated with Glasgow Coma Score (GCS) (p<0.02) and duration of coma (p<0.01). The presence of associated intracranial haematoma >25 ml portended an adverse outcome. A logistic regression analysis revealed age, GCS, state of perimesencephalic cisterns and pupillary dilation to be independent predictors of poor outcome. Residual sequelae (focal deficits, cognitive deficits, postconcussion syndrome) were evident in nearly half of patients with diffuse axonal injury (DAI) and a lucid interval.

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