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Fulltext Quantitative evaluation of chimerism status following haematopoeitic stem cell transplantation using a microchip electrophoresis system

Daud, S.S., Ibrahim, K., Ariffin, H.

JUMMEC, 2007;10(1):11-16.
MyJurnal

We aimed to establish a method for quantitative analysis of mixed haematopoietic chimerism based on microchip electrophoresis of selected molecular markers following PCR amplification for accurate monitoring of graft status post-transplantation. A 12-year-old girl with relapsed acute lymphoblastic leukaemia who underwent allogeneic bone marrow transplantation had qualitative chimerism analysis using short tandem repeat markers at three time points following the procedure. Her archived DNA samples were then used to test the ability to correlate her clinical course with changes in the quantity of donor chimerism at the different time points. Quantitative chimerism analysis was performed on the Agilent 2100 bioanalyser and donor-recipient ratios were calculated from generated electropherograms. Complete donor chimerism (98%) was demonstrated three weeks post- transplantation. Decreasing amount of donor chimerism to 24% was shown after three months and this concurred with clinical relapse. Following a second transplant, full donor chimerism was reestablished where donor chimerism rose to 100%. High resolution microchip electrophoresis could be useful in predicting the occurrence of increasing recipient chimerism which may herald impending relapse in patients while the disease burden is still low. This investigational approach may provide useful information for clinicians to select appropriate intervention strategies to ensure successful transplantation.
Periorbital syringoma: a pilot study of the efficacy of low-voltage electrocoagulation

Al Aradi IK

Dermatol Surg, 2006 Oct;32(10):1244-50.
PMID: 17034373

Management of periorbital syringomas is problematic and avoided by many inexperienced physicians. The medical literature presently prefers CO(2) laser resurfacing to many other modalities, but the subject of electrosurgery has not been well explored.
Perception of community pharmacists towards the barriers to enhanced pharmacy services in the healthcare system of Dubai: a quantitative approach

Rayes IK, Hassali MA, Abduelkarem AR

Pharm Pract (Granada), 2015 06 15;13(2):506.
PMID: 26131039

BACKGROUND: In many developing countries, pharmacists are facing many challenges while they try to enhance the quality of services provided to patients approaching community pharmacies.
OBJECTIVE: To explore perception of community pharmacists in Dubai regarding the obstacles to enhanced pharmacy services using a part of the results from a nation-wide quantitative survey.
METHODS: A questionnaire was distributed to 281 full-time licensed community pharmacists in Dubai. The questionnaire had 5 inter-linked sections: demographic information, information about the pharmacy, interaction with physicians, pharmacists' current professional role, and barriers to enhanced pharmacy services.
RESULTS: About half of the respondents (45.4%, n=90) agreed that pharmacy clients under-estimate them and 52.5% (n=104) felt the same by physicians. About 47.5% (n=94) of the respondents felt that they are legally unprotected against profession's malpractice. Moreover, 64.7% (n=128) stated that pharmacy practice in Dubai turned to be business-focused. In addition, 76.8% (n=252) found that one of the major barriers to enhanced pharmacy services is the high business running cost. Pharmacists screened tried to prove that they are not one of the barriers to optimized pharmacy services as 62.7% (n=124) disagreed that they lack appropriate knowledge needed to serve community and 67.7% (n=134) gave the same response when asked whether pharmacy staff lack confidence when treating consumers or not.
CONCLUSIONS: Although being well established within the community, pharmacists in Dubai negatively perceived their own professional role. They stated that there are number of barriers which hinder optimized delivery of pharmacy services like under-estimation by pharmacy clients and other healthcare professionals, pressure to make sales, and high running cost.
Fulltext ZFP36L2 silencing increases sensitivity to Temolozomide via G2M cell cycle arrest and BAX mediated apoptosis

Che Mat M. F., Mohamad Hanif E. A., Abdul Murad N. A., Ibrahim K., Harun R.

Malaysian Journal of Medicine and Health Sciences, 2019;15(102):11-11.
MyJurnal

Introduction: The mortality rate of glioma patients particularly with glioblastoma multiforme (GBM) remains high even with advancements in the multimodality treatment. This is partly due to chemoresistance of the glioma cells towards drug treatment which finally reduced the survival of GBM patients. In this study, we determined the chemosensitisation and oncogenic characteristics of ZFP36L2 in LN18 GBM cells using RNA interference (RNAi). Methods: Meta-analysis of microarray datasets was used to identify the druggable genes responsive to GBM chemosensitivity. Subsequently, the genes were validated using RNAi screening [pooled small interference RNA (siRNA)]. Temozolomide- resistant LN18 cells were used to evaluate the effects of gene silencing on chemosensitisation to the sub-lethal dose (1/10 of IC50) of temozolomide. Assays such as cell viability, proliferation, migration and invasion and apoptosis assays were carried out. The apoptosis pathway underlying chemosensitisation by ZFP36L2 siRNA was determined using a human apoptosis array kit. Statistical analyses were performed using one-way analysis of variance. Results: ZFP36L2 was identified as a potential marker of GBM based on the meta-analysis and RNAi screening. ZFP36L2 knockdown lead to 1) Apoptosis induction (p < 0.05) 2) Reduced cell migration (p < 0.05) 3) Reduced up to 82% of cell invasion (p < 0.01) and 4) Decreased cellular proliferation in siZFP36L2-treated LN18 cells. Downstream analysis showed that the sub-lethal dose of temozolomide caused major upregulation of BCL2-associated X, apoptosis regulator (BAX). Conclusion: ZFP36L2 is oncogenic and chemosensitive thus may contribute to gliomagenesis through cell proliferation, migration, invasion and apoptosis. RNAi therapy in combination with chemotherapy treatment such as temozolomide may serve as potential therapeutic approach in the future.
Fulltext COVID-19 pandemic: Lessons learned for undergraduate research training

Ibrahim K, Ahmad-Annuar A

Biochem Mol Biol Educ, 2022 09;50(5):476-478.
PMID: 36054325 DOI: 10.1002/bmb.21665

This article reports a session from the virtual international 2021 IUBMB/ASBMB workshop, "Teaching Science on Big Data." The awareness of using publicly available research data sets for undergraduate training is low in certain parts of the world. Final year projects always revolve around wet-lab based projects. The challenges occur during COVID-19 pandemic when it forces full lockdown to the nation, but at the same time faculty members need to provide consistent training to the students and projects to work with. We aim to identify supervisors in the faculty that are ready to convert their proposed project from wet-lab to an online-based project. As coordinators of the course we created an online survey to identify projects that can be converted into dry-lab/online projects. Our surveys identified only 32.5% projects implemented dry-lab/online based projects. Most academicians described that they are not ready or familiar to apply changes for their research design. With the unknown future of the world living with COVID-19 and directional changes of life science research toward big data driven research indeed we should be ready to adopt such changes. Awareness on reusing public data sets as tools for research should be provided to strengthen undergraduate training. Life science undergraduates should be exposed to reusing public data sets as these materials are readily available case studies that allow in depth exploration to answer specific research questions. Members of the faculty should take part to pave the way for them, ensuring that they understand that life science research revolves around a multidisciplinary field.
Fulltext On Bayesian approach to composite Pareto models

Abdul Majid MH, Ibrahim K

PLoS One, 2021;16(9):e0257762.
PMID: 34555115 DOI: 10.1371/journal.pone.0257762

In data modelling using the composite Pareto distribution, any observations above a particular threshold value are assumed to follow Pareto type distribution, whereas the rest of the observations are assumed to follow a different distribution. This paper proposes on the use of Bayesian approach to the composite Pareto models involving specification of the prior distribution on the proportion of data coming from the Pareto distribution, instead of assuming the prior distribution on the threshold, as often done in the literature. Based on a simulation study, it is found that the parameter estimates determined when using uniform prior on the proportion is less biased as compared to the point estimates determined when using uniform prior on the threshold. Applications on income data and finance are included for illustrative examples.
Fulltext On the application of structural equation modeling for the construction of a health index

Yanuar F, Ibrahim K, Jemain AA

Environ Health Prev Med, 2010 Sep;15(5):285-91.
PMID: 21432557 DOI: 10.1007/s12199-010-0140-7

OBJECTIVE: The health of an individual is influenced by many factors. These could include factors that are related to the economy and the environment, as well as social and biological factors. Many studies have been carried out to study the effect of these factors on health, in terms of the individual factors or combined factors. The main purpose of this study was to demonstrate the value of structural equation modeling for the construction of an index to describe the health status of an individual.
METHODS: Structural equation modeling was applied to data obtained from 5035 respondents in a survey conducted in the district of Hulu Langat, Malaysia, in the year 2001 by the Department of Community Health, Medical Faculty, Universiti Kebangsaan Malaysia, Malaysia. The survey involved the gathering of information on the respondents' demography, lifestyles, mental health condition, and biomarkers.
RESULTS: Socio-demography and mental health condition were found to have a direct effect on the health index. However, lifestyle had an indirect effect on the health index, as mediated by the mental health. Based on the indicator of model fit, the proposed model fits the data well.
CONCLUSIONS: Structural equation modeling was found to be pertinent to be used for analyzing the health index of a particular individual.
Modeling air quality in main cities of Peninsular Malaysia by using a generalized Pareto model

Masseran N, Razali AM, Ibrahim K, Latif MT

Environ Monit Assess, 2016 Jan;188(1):65.
PMID: 26718946 DOI: 10.1007/s10661-015-5070-9

The air pollution index (API) is an important figure used for measuring the quality of air in the environment. The API is determined based on the highest average value of individual indices for all the variables which include sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and suspended particulate matter (PM10) at a particular hour. API values that exceed the limit of 100 units indicate an unhealthy status for the exposed environment. This study investigates the risk of occurrences of API values greater than 100 units for eight urban areas in Peninsular Malaysia for the period of January 2004 to December 2014. An extreme value model, known as the generalized Pareto distribution (GPD), has been fitted to the API values found. Based on the fitted model, return period for describing the occurrences of API exceeding 100 in the different cities has been computed as the indicator of risk. The results obtained indicated that most of the urban areas considered have a very small risk of occurrence of the unhealthy events, except for Kuala Lumpur, Malacca, and Klang. However, among these three cities, it is found that Klang has the highest risk. Based on all the results obtained, the air quality standard in urban areas of Peninsular Malaysia falls within healthy limits to human beings.
Low-temperature solution-processed flexible solar cells based on (In,Ga)N nanocubes

Qaeed MA, Ibrahim K, Saron KM, Ahmed MA, Allam NK

ACS Appl Mater Interfaces, 2014 Jul 9;6(13):9925-31.
PMID: 24937197 DOI: 10.1021/am502217b

Indium gallium nitride nanocubes were syntheized via a low-temperature chemical route. Energy-dispersive X-ray spectroscopy and X-ray diffraction analyses confirmed the successful fabrication of (In,Ga)N with various indium mole fractions. The bandgap of the material was tunded as a function of the indium content. The fabricated nanocubes showed a deep level photoluminescence emission at 734 nm as well as in the visible region at 435-520 nm. The Hall effect measurements showed the hole concentration to constantly increase from 6.2 × 10(16) to 2.3 × 10(18) cm(-3), while the hole mobility to decrease from 0.92 to 0.1 cm(2) /(V s) as the doping ratio increases from 0.005 to 0.025 cm(-3). The solar cell device made of nanocubes film containing 0.4 indium on flexible substrates showed a short-circuit current density of 12.47 mA/cm(2) and an open-circuit voltage (Voc) of 0.48 V with 54% fill factor. The relationship between Voc and indium content in the fabricated films was also investigated.
Accumulation of trace metals in the embryos and hatchlings of Chelonia mydas from Peninsular Malaysia incubated at different temperatures

Ikonomopoulou MP, Olszowy H, Francis R, Ibrahim K, Whittier J

Sci Total Environ, 2013 Apr 15;450-451:301-6.
PMID: 23500829 DOI: 10.1016/j.scitotenv.2013.02.031

A variety of trace metals were measured in the egg contents of three clutches of Chelonia mydas collected from Kuala Terengganu state in Peninsular Malaysia. We quantified Mn, Cu, Zn, Se (essential trace metals) and As (anthropogenic pollutant) at several developmental stages obtained by incubating eggs at two different temperatures (27 °C and 31 °C). The incubation temperatures were chosen because they produce predominantly male or predominantly female hatchlings, respectively. The eggs were removed from the sand and washed before being placed in incubators, to ensure that the only possible source of the detected metals was maternal transfer. Other metals: Mo, Co, Ni, Cd, Sn, Sb, Hg, Tl and Pb (all non-essential metals) were detected at concentrations below the lower limit of quantitation (LLOQ). Trace metal concentrations, particularly [Zn], increased during development, other metals (Cu, As, Se and Cr) accumulated to a lesser degree than zinc but no significant differences were observed between the incubation temperatures at any stage of incubation. To date, only a few studies on trace metals in turtle embryos and hatchlings have been reported; this study will provide basic knowledge on the accumulation of trace metals during development at two different incubation temperatures.
Development of an algorithm of satellite markers for monitoring chimerism status in post-allogeneic haematopoietic stem cell transplantation patients

Choong SS, Rosmanizam S, Ibrahim K, Gan GG, Ariffin H

Int J Lab Hematol, 2011 Apr;33(2):182-6.
PMID: 20868447 DOI: 10.1111/j.1751-553X.2010.01264.x

Analysis of variable number tandem repeats (VNTRs) by polymerase chain reaction (PCR) is a common method used to predict engraftment status in post-allogeneic haematopoeitic stem cell transplantation (HSCT) patients. Different populations have different copies of repeated DNA sequence and hence, different percentage of informativeness between patient and donor.
Li-Fraumeni syndrome in a Malaysian kindred

Ariffin H, Martel-Planche G, Daud SS, Ibrahim K, Hainaut P

Cancer Genet. Cytogenet., 2008 Oct;186(1):49-53.
PMID: 18786442 DOI: 10.1016/j.cancergencyto.2008.06.004

We report on a Malaysian kindred with Li-Fraumeni syndrome. The proband was an 8-year-old girl who presented with embryonal rhabdomyosarcoma of the trunk at the age of 8 months and developed a brain recurrence at the age of 7 years, which was 5 years after remission. A younger sister later developed adrenocortical carcinoma at the age of 6 months. Their mother and maternal grandmother were diagnosed with breast cancer at the ages of 26 and 38 years, respectively. TP53 mutation detection in this family revealed a duplication of a GGCGTG motif starting at nucleotide 17579 in exon 10, resulting in an in-frame insertion of two amino acids between residues 334 and 336 in the tetramerization domain of the p53 protein. This mutation was found in the proband and her affected sister as well as her mother. In addition, the mutation was detected in two other siblings (a brother aged 3 years and a sister aged 18 months) who have not yet developed any malignancy. Sequencing of TP53 in the father and two other asymptomatic siblings revealed wild-type TP53. To our knowledge, this is a first report of a Li-Fraumeni syndrome family in Southeast Asia.
Fulltext Effect of pentoxifylline on tumor necrosis factor-alpha and interleukin-6 levels in neonatal sepsis

Selim K, Hüseyin C, Ibrahim KH, Hasan BU, Kazim U, Hüseyin K

Med J Malaysia, 2004 Aug;59(3):391-4.
PMID: 15727386

Several pharmacological agents have been found to alter systemic concentrations and/or the activity of different cytokines via a variety of mechanisms, including changes in biosynthesis, secretion, and/or stability. Pentoxifylline (PTX), which is a methylxanthine derivative for example, has multiple effects on the immune system, but inhibition of pro-inflammatory cytokine release predominates. In this study we aimed to evaluate the influence of PTX on plasma levels of tumor necrosis factor (TNF) alpha and interleukin (IL)-6 in newborn infants with sepsis. The study included 20 infants with neonatal sepsis. In all subjects blood samples for serum C-reactive protein, TNF alpha and IL-6 determinations were received before giving PTX and at the 12th and 24th hours following PTX. In addition, white blood cell was counted before giving PTX and on the 3rd and 7th day following PTX. The infants were randomly divided into two groups. Firstly, PTX was used in infants who were successively admitted to the clinic and the subsequent infants were accepted as a control group. Of 20 infants, 13 infants received PTX and seven infants did not. We did not find any difference in the leukocyte count, serum C-reactive protein level, TNF alpha and IL-6 levels between the two groups of patients (P>0.05). While three infants died in the group of receiving PTX, death was not recorded in the group of non-receiving PTX (P>0.05). Our findings showed that PTX treatment did not affect leukocyte counts, serum CRP levels, TNF alpha and IL-6 levels and death ratio in newborn infants with sepsis. The last result may be due to the fact that the number of patients in the study was very small. We think that more extensive and controlled studies should be performed about this subject.
Modeling the spatio-temporal dynamics of air pollution index based on spatial Markov chain model

Alyousifi Y, Ibrahim K, Kang W, Zin WZW

Environ Monit Assess, 2020 Oct 21;192(11):719.
PMID: 33083907 DOI: 10.1007/s10661-020-08666-8

An environmental problem which is of concern across the globe nowadays is air pollution. The extent of air pollution is often studied based on data on the observed level of air pollution. Although the analysis of air pollution data that is available in the literature is numerous, studies on the dynamics of air pollution with the allowance for spatial interaction effects through the use of the Markov chain model are very limited. Accordingly, this study aims to explore the potential impact of spatial dependence over time and space on the distribution of air pollution based on the spatial Markov chain (SMC) model using the longitudinal air pollution index (API) data. This SMC model is pertinent to be applied since the daily data of API from 2012 to 2014 that have been gathered from 37 different air quality stations in Peninsular Malaysia is found to exhibit the property of spatial autocorrelation. Based on the spatial transition probability matrices found from the SMC model, specific characteristics of air pollution are studied in the regional context. These characteristics are the long-run proportion and the mean first passage time for each state of air pollution. It is found that the probability for a particular station's state to remain good is 0.814 if its neighbors are in a good state of air pollution and 0.7082 if its neighbors are in a moderate state. For a particular station having neighbors in a good state of air pollution, the proportion of time for it to continue being in a good state is 0.6. This proportion reduces to 0.4, 0.01, and 0 for the cell of moderate, unhealthy, and very unhealthy states, respectively. In addition, there exists a significant spatial dependence of API, indicating that air pollution for a particular station is dependent on the states of the neighboring stations.
Correction to: Modeling the spatio-temporal dynamics of air pollution index based on spatial Markov chain model

Alyousifi Y, Ibrahim K, Kang W, Zin WZW

Environ Monit Assess, 2020 Nov 08;192(12):753.
PMID: 33164139 DOI: 10.1007/s10661-020-08720-5

The original version of this article unfortunately contained an error in the affiliation section and in the main body text.
Fulltext Knockdown of Tousled‑like kinase 1 inhibits survival of glioblastoma multiforme cells

Ibrahim K, Abdul Murad NA, Harun R, Jamal R

Int J Mol Med, 2020 Aug;46(2):685-699.
PMID: 32468002 DOI: 10.3892/ijmm.2020.4619

Glioblastoma multiforme (GBM) is an aggressive type of brain tumour that commonly exhibits resistance to treatment. The tumour is highly heterogenous and complex kinomic alterations have been reported leading to dysregulation of signalling pathways. The present study aimed to investigate the novel kinome pathways and to identify potential therapeutic targets in GBM. Meta‑analysis using Oncomine identified 113 upregulated kinases in GBM. RNAi screening was performed on identified kinases using ON‑TARGETplus siRNA library on LN18 and U87MG. Tousled‑like kinase 1 (TLK1), which is a serine/threonine kinase was identified as a potential hit. In vitro functional validation was performed as the role of TLK1 in GBM is unknown. TLK1 knockdown in GBM cells significantly decreased cell viability, clonogenicity, proliferation and induced apoptosis. TLK1 knockdown also chemosensitised the GBM cells to the sublethal dose of temozolomide. The downstream pathways of TLK1 were examined using microarray analysis, which identified the involvement of DNA replication, cell cycle and focal adhesion signalling pathways. In vivo validation of the subcutaneous xenografts of stably transfected sh‑TLK1 U87MG cells demonstrated significantly decreased tumour growth in female BALB/c nude mice. Together, these results suggested that TLK1 may serve a role in GBM survival and may serve as a potential target for glioma.
Fulltext Effect of sulfurization time on the properties of copper zinc tin sulfide thin films grown by electrochemical deposition

Aldalbahi A, Mkawi EM, Ibrahim K, Farrukh MA

Sci Rep, 2016;6:32431.
PMID: 27600023 DOI: 10.1038/srep32431

We report growth of quaternary Cu2 ZnSnS4 (CZTS) thin films prepared by the electrochemical deposition from salt precursors containing Cu (II), Zn (II) and Sn (IV) metals. The influence of different sulfurization times t (t = 75, 90, 105, and 120 min) on the structural, compositional, morphological, and optical properties, as well as on the electrical properties is studied. The films sulfurized 2 hours showed a prominent kesterite phase with a nearly stoichiometric composition. Samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and Raman and UV-VIS-NIR spectrometer at different stages of work. X-ray diffraction and Raman spectroscopy analyses confirmed the formation of phase-pure CZTS films. (FESEM) shows that compact and dense morphology and enhanced photo-sensitivity. STEM - EDS elemental map of CZTS cross-section confirms homogeneous distribution. From optical study, energy gap was enlarged with a changed sulfurization times in the range of 1.37-1.47 eV.
Early Experience, Setup, Learning Curve, Benefits, and Complications Associated with Exoscope and Three-Dimensional 4K Hybrid Digital Visualizations in Minimally Invasive Spine Surgery

Ariffin MHM, Ibrahim K, Baharudin A, Tamil AM

Asian Spine J, 2019 Oct 15.
PMID: 31608611 DOI: 10.31616/asj.2019.0075

Study Design: Prospective observational study (n=74).
Purpose: To evaluate the learning curve for exoscope and three-dimensional (3D) 4K hybrid visualization in terms of operating time, advantages, disadvantages, and surgical complications in tubular-access minimally invasive spine surgery (MISS) and to assess surgeon satisfaction with image quality, ergonomics, and ability to perform target site treatment.
Overview of Literature: Working through tubular retractors poses a challenge. The extreme angulations during microsurgical decompression, especially contralateral decompression, require surgeons to work non-ergonomically. An exoscope allows surgeons to work ergonomically and independently of the microscope oculars as visualizations are now provided by large 3D 4K monitors. However, the value and efficacy of solely depending on an exoscope and 3D 4K monitors during microsurgical work are still unknown.
Methods: Seventy-four patients (99 levels) underwent trans-tubular MISS between March 2018 and January 2019. Five patients were excluded: one had pyogenic discitis, two had revisions, and two were trans-tubular transoral. In total, we analyzed 69 for operating time, blood loss, and complications. The learning curve graph was plotted using the surgical time for each procedure. Surgeons were asked to rate their satisfaction with image quality, ability to maintain ergonomic posture, and efficient target site treatment.
Results: For tubular microdiscectomy, the operating time plateaued after six cases, and for tubular decompression and minimally invasive transforaminal lumbar interbody fusion, the operating time plateaued after nine cases. Mean operating time was significantly reduced after the plateau. Complications included four cases of dural tear. All patients improved symptomatically, and there were no postoperative neurological deficits.
Conclusions: Use of the exoscope has a short learning curve. Surgeons benefit from improved ergonomic posture during surgery, and resident teaching appears to be good. The only drawback is the need to rearrange the operating table setup. Complications were comparable to those when using the surgical microscope. An exoscope with hybrid digital visualization provides excellent visualization, depth perception, clarity, and precision target site treatment.
Fulltext Robust empirical Bayes approach for Markov chain modeling of air pollution index

Alyousifi Y, Ibrahim K, Kang W, Zin WZW

J Environ Health Sci Eng, 2021 Jun;19(1):343-356.
PMID: 34150239 DOI: 10.1007/s40201-020-00607-4

Air pollution is a matter of concern among the public, especially for those living in urban and industrial areas. Markov chain modeling is often used to model the underlying dynamics of air pollution, which involves describing the transition probability of going from one air pollution state to another. Thus, estimating the transition probability matrix for the data of the air pollution index (API) is an essential process in the modeling. However, one may observe many zero probabilities in the transition probability matrix, especially when faced with a small sample, interpreting the results with respect to the climate condition less realistic. This study proposes a robust empirical Bayes method, which incorporates a method of smoothing the zero frequencies in the count matrix, contributing to an improved estimation of the transition probability matrix. The robustness of the empirical Bayesian estimation is investigated based on Bayes risk. The transition probability matrices estimated based on the robust empirical Bayes method for the hourly API data collected from seven monitoring stations in Malaysia for the period 2012 to 2014 are used for determining the air pollution characteristics such as the mean residence time, the steady-state probability and the mean recurrence time. Furthermore, the proposed method has been evaluated by Monte Carlo simulations. Results suggest that it is quite effective in producing non-zero transition probability estimates, and superior to the maximum likelihood method in terms of minimizing the mean squared error for individual and entire transition probabilities. Therefore, the robust empirical Bayes method proves to be an improved approach to the estimation of the Markov chain. When applied to API data, it could provide important information on air pollution dynamics that may help guiding the development of proper strategies for managing the impact of air quality.
Supplementary Information: The online version contains supplementary material available at 10.1007/s40201-020-00607-4.
Fulltext Osteoradionecrosis in Subaxial Cervical Spine - a Rare and Devastating Complication: A Case Report

Rashid MZ, Ariffin MH, Rhani SA, Baharudin A, Ibrahim K

Malays Orthop J, 2017 Nov;11(3):53-55.
PMID: 29326769 MyJurnal DOI: 10.5704/MOJ.1711.005

Osteoradionecrosis, a rare complication of radiation therapy, is a slow progression disease which affects the surrounding structures of spinal components. It essentially weakens the soft tissue and bony configuration and can cause nerve impingement or cord compression. We describe a patient who underwent radiotherapy for thyroid cancer and presented with cervical kyphosis with anterolisthesis of C3/C4 and C4/C5 some 32 years later. We explore the role of anterior and posterior fusion, as well as hyperbaric oxygen therapy in promoting healing.

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