Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 35
Filter
1.
Med J Malaysia ; 78(5): 635-638, 2023 09.
Article in English | MEDLINE | ID: mdl-37775491

ABSTRACT

INTRODUCTION: Epilepsy is a neurological disease with high global prevalence. Almost one-third of epilepsy patients continue having seizures despite adequate treatment. Perampanel has been widely used in the Western countries as an adjunctive therapy for both generalized and focal seizures. Owing to its high cost, the use of perampanel is limited in our country. MATERIALS AND METHODS: We conducted a descriptive, retrospective study among epilepsy patients treated with perampanel. We aimed to assess the efficacy and safety of perampanel as an adjunctive in our hospital. RESULTS AND CONCLUSIONS: From our cohort of 25 patients, most of the patients were either on one or three anti-seizure medications (ASMs) prior to initiation of perampanel. Perampanel was added in 88% of them due to persistent seizures. Twenty-two (88%) patients experienced reduction in seizure frequency. 12% experienced mild side effects, which were leg cramps, hyponatremia and drowsiness. Only 1 patient stopped perampanel due to its side effects. CONCLUSION: Perampanel is a well-tolerated ASM that should be widely used as an adjunctive. More studies with regards to its efficacy and safety involving more centres are encouraged in Malaysia.


Subject(s)
Anticonvulsants , Epilepsy , Humans , Retrospective Studies , Anticonvulsants/therapeutic use , Anticonvulsants/adverse effects , Treatment Outcome , Drug Therapy, Combination , Epilepsy/drug therapy , Epilepsy/chemically induced
2.
Med J Malaysia ; 77(5): 526-533, 2022 09.
Article in English | MEDLINE | ID: mdl-36169062

ABSTRACT

INTRODUCTION: In the past decades, water-related disasters had been accounted for about three-quarters of all-natural disasters worldwide. Asia is the most affected region with more than 45% of fatalities and more than 90% of the victims affected by aquatic disasters. Aquatic events progress differently and rapidly as compared to inland disasters. Thus, apart from additional equipments and trained aquatic rescuers, aquatic disaster operation requires specific strategies and tactics. MATERIALS AND METHODS: This qualitative study was conducted using mixed methods involving the Delphi method and decision-conferencing approach. Two rounds of open-ended questionnaires were sent to subject matter experts from rescue agencies that involved in aquatic disaster rescue and management. Feedback from the panel was reviewed, the natural history of different aquatic disasters was appraised, and the decision-analysis model on the command, control and management of aquatic disaster was developed. The model was then reassessed through an iteration process at decision-conferencing among the expert panel until the final framework was accepted by all members of the panel. RESULTS: The fast progression of aquatic disasters with multiple hazards on the scene and unique technical challenges of the operation increase the risk of rescuers to become victims themselves. The developed conceptual framework, namely Aquatic Disaster Activation Plan and Tactic (ADAPT), was found able to guide rescuers in risk assessment, judgment, and response in aquatic disasters based on strategies and tactics for different phases along the natural history of aquatic disasters. CONCLUSION: With realistic scenario-based training and drills, ADAPT can be the blueprint in aquatic disaster management. It is designed to facilitate rescue agencies and organizations in preparing and executing the technical aquatic rescue operations safely, according to the resources available and the capability of the respective rescue organization.


Subject(s)
Disaster Planning , Disasters , Humans , Risk Assessment , Surveys and Questionnaires
3.
Osteoarthritis Cartilage ; 29(8): 1096-1116, 2021 08.
Article in English | MEDLINE | ID: mdl-33971205

ABSTRACT

OBJECTIVE: To determine the prevalence of neuropathic-like pain (NP) and pain sensitization (PS) defined by self-report questionnaires in knee and hip osteoarthritis, and whether prevalence is potentially explained by disease-severity or affected joint. DESIGN: MEDLINE, EMBASE, CINAHL were systematically searched (1990-April 2020) for studies describing the prevalence of NP and PS in knee and hip osteoarthritis using self-report questionnaires. Random-effects meta-analysis was performed. Statistical heterogeneity between studies and sub-groups (affected joint and population source as a proxy for disease severity) was assessed (I2 statistic and the Chi-squared test). RESULTS: From 2,706 non-duplicated references, 39 studies were included (2011-2020). Thirty-six studies reported on knee pain and six on hip pain. For knee osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP(score ≥13) 40% (95%CI 32-48%); probable NP(score >18) 20% (95%CI 15-24%); using Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, 32% (95%CI 26-38%); using Douleur Neuropathique (DN4) 41% (95% CI 24-59%). The prevalence of PS using Central Sensitization Inventory (CSI) was 36% (95% CI 12-59%). For hip osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP 29% (95%CI 22-37%%); probable NP 9% (95%CI 6-13%); using DN4 22% (95%CI 12-31%) in one study. The prevalence of possible NP pain was higher at the knee (40%) than the hip (29%) (difference 11% (95% CI 0-22%), P = 0.05). CONCLUSIONS: Using self-report questionnaire tools, NP was more prevalent in knee than hip osteoarthritis. The prevalence of NP in knee and hip osteoarthritis were similar for each joint regardless of study population source or tool used. Whether defining NP using self-report questionnaires enables more effective targeted therapy in osteoarthritis requires investigation.


Subject(s)
Central Nervous System Sensitization/physiology , Neuralgia/physiopathology , Osteoarthritis, Hip/physiopathology , Osteoarthritis, Knee/physiopathology , Humans , Prevalence
4.
Osteoarthritis Cartilage ; 28(11): 1403-1411, 2020 11.
Article in English | MEDLINE | ID: mdl-32791103

ABSTRACT

BACKGROUND: Almost a third of those undergoing knee replacement for osteoarthritis have poor outcomes despite technically successful surgery. Preoperative neuropathic-like pain and/or pain sensitisation may increase the risk of pain following joint replacement. OBJECTIVE: To examine whether preoperative neuropathic-like pain and pain sensitisation predicts pain, function and satisfaction following joint replacement for knee osteoarthritis. DESIGN: Systematic review with meta-analysis. METHODS: Medline, EMBASE and CINAHL were systematically searched until March 2020. Studies detecting neuropathic-like pain and/or sensitisation using self-report questionnaires prior to knee replacement for osteoarthritis, and relating this to post-operative outcomes were identified. Data extraction, risk of bias assessment and meta-analysis were performed, where appropriate. RESULTS: Five manuscripts, including one preprint, examining six cohorts were included: four used painDETECT or modified painDETECT, one the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, and another the Central Sensitisation Inventory to identify preoperative characteristics. Three studies showed preoperative neuropathic-like pain or sensitisation was associated with more intense post-operative pain. All four studies examining the risk of significant pain after knee replacement suggested it was increased after >3 months. The only study examining patient satisfaction and function found reduced satisfaction, but no difference in function in those with preoperative sensitisation. Meta-analysis found the relative risk of increased pain following knee replacement in those with neuropathic-like pain (painDETECT ≥13) to be 2.05 (95% confidence intervals 1.51, 2.79). CONCLUSION: These results provide consistent but limited evidence that self-report tools detecting neuropathic-like pain and/or pain sensitisation, predict patients at higher risk of pain following knee replacement.


Subject(s)
Arthroplasty, Replacement, Knee , Central Nervous System Sensitization/physiology , Neuralgia/physiopathology , Osteoarthritis, Knee/physiopathology , Osteoarthritis, Knee/surgery , Pain, Postoperative/epidemiology , Humans , Patient Satisfaction , Preoperative Period , Prognosis
5.
J Child Neurol ; 35(13): 901-907, 2020 11.
Article in English | MEDLINE | ID: mdl-32720856

ABSTRACT

Genetically determined leukoencephalopathies comprise a group of rare inherited white matter disorders. The majority are progressive diseases resulting in early death. We performed a cross-sectional pilot study including 55 parents from 36 families to assess the level of stress experienced by parents of patients with genetically determined leukoencephalopathies, aged 1 month to 12 years. Thirty-four mothers and 21 fathers completed the Parenting Stress Index-4th Edition. One demographic questionnaire was completed per family. Detailed clinical data was gathered on all patients. Statistical analysis was performed with total stress percentile score as the primary outcome. Mothers and fathers had significantly higher stress levels compared with the normative sample; 20% of parents had high levels of stress whereas 11% had clinically significant levels of stress. Mothers and fathers had comparable total stress percentile scores. We identified pediatric behavioral difficulties and gross motor function to be factors influencing stress in mothers. Our study is the first to examine parental stress in this population and highlights the need for parental support early in the disease course. In this pilot study, we demonstrated that using the Parenting Stress Index-4th Edition to assess stress levels in parents of patients with genetically determined leukoencephalopathies is feasible, leads to valuable and actionable results, and should be used in larger, prospective studies.


Subject(s)
Leukoencephalopathies/psychology , Parents/psychology , Stress, Psychological/psychology , Adult , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Pilot Projects , Surveys and Questionnaires
6.
Med J Malaysia ; 75(4): 430-432, 2020 07.
Article in English | MEDLINE | ID: mdl-32724009

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is a debilitating progressive lung disease characterised by irreversible airflow obstruction. In addition to an increase in morbidity and mortality, exacerbation also results in frequent hospital visits, which place a burden on healthcare systems. Non-invasive positive pressure ventilation (NPPV) with conventional inspiratory pressures is the standard ventilatory support for patients in exacerbation. At present, the use of higher inspiratory pressures through high intensity noninvasive positive pressure ventilation (Hi-NPPV) during an exacerbation remains unknown. We describe a novel application of Hi-NPPV in a patient with acute exacerbation who was refractory to conventional NPPV.


Subject(s)
Noninvasive Ventilation , Positive-Pressure Respiration , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/pathology , Respiratory Insufficiency/etiology , Aged , Humans , Male , Noninvasive Ventilation/instrumentation , Positive-Pressure Respiration/instrumentation , Treatment Outcome
7.
Br J Radiol ; 85(1015): 1018-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21976634

ABSTRACT

Yttrium-90 ((90)Y) internal pair production can be imaged by positron emission tomography (PET)/CT and is superior to bremsstrahlung single-photon emission CT/CT for evaluating hepatic (90)Y microsphere biodistribution. We illustrate a case of (90)Y imaging using first generation PET/CT technology, producing high-quality images for qualitative diagnostic purposes.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Neoplasm Recurrence, Local/diagnostic imaging , Radiopharmaceuticals , Yttrium , Carcinoma, Hepatocellular/surgery , Catheter Ablation/methods , Female , Humans , Liver Neoplasms/surgery , Microspheres , Middle Aged , Multimodal Imaging , Neoplasm Recurrence, Local/surgery , Neoplasm Staging , Positron-Emission Tomography , Quality Control , Sensitivity and Specificity , Tomography, X-Ray Computed
8.
Int J Tuberc Lung Dis ; 15(8): 1111-6, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21740677

ABSTRACT

SETTING: The impact on patient mortality of combined pulmonary fibrosis and emphysema (CPFE) compared with emphysema alone has never been investigated. OBJECTIVE: To elucidate whether CPFE has an impact on overall mortality over that of emphysema alone. DESIGN: We screened patients who underwent chest computed tomography (CT) scans during the period from 1 January 2001 to 31 December 2005 in a tertiary referral hospital. Patients who had both emphysema and pulmonary fibrosis, thus meeting the inclusion criteria, were defined as CPFE. Controls with emphysema alone who were matched for age, sex and the date of CT scan were randomly selected. Cox proportional regression analysis was performed to verify whether CPFE is associated with increased overall mortality. RESULTS: We found 135 CPFE cases. In the multivariable Cox regression stratified by the presence of comorbid malignancy, CPFE had five times higher mortality risk (adjusted HR 5.10, 95%CI 1.75-14.9) in non-malignant cases, and showed a statistically insignificant trend for higher mortality risk (adjusted HR 1.70, 95%CI 0.94-2.51) in the malignant cases after adjusting for forced vital capacity, height and hypertension. CONCLUSION: CPFE is not rare and CPFE patients had a higher overall mortality risk than emphysema-only patients.


Subject(s)
Pulmonary Emphysema/mortality , Pulmonary Fibrosis/mortality , Aged , Aged, 80 and over , Case-Control Studies , Chi-Square Distribution , Comorbidity , Female , Hospitals, University , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasms/mortality , Prognosis , Proportional Hazards Models , Pulmonary Emphysema/diagnostic imaging , Pulmonary Fibrosis/diagnostic imaging , Republic of Korea/epidemiology , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Tomography, X-Ray Computed
9.
Folia Phoniatr Logop ; 62(3): 127-33, 2010.
Article in English | MEDLINE | ID: mdl-20424468

ABSTRACT

Apraxia of speech (AOS) is a motor speech disorder characterized by disturbed spatial and temporal parameters of movement. Research on motor learning suggests that augmented feedback may provide a beneficial effect for training movement. This study examined the effects of the presence and frequency of online augmented visual kinematic feedback (AVKF) and clinician-provided perceptual feedback on speech accuracy in 2 adults with acquired AOS. Within a single-subject multiple-baseline design, AVKF was provided using electromagnetic midsagittal articulography (EMA) in 2 feedback conditions (50 or 100%). Articulator placement was specified for speech motor targets (SMTs). Treated and baselined SMTs were in the initial or final position of single-syllable words, in varying consonant-vowel or vowel-consonant contexts. SMTs were selected based on each participant's pre-assessed erred productions. Productions were digitally recorded and online perceptual judgments of accuracy (including segment and intersegment distortions) were made. Inter- and intra-judge reliability for perceptual accuracy was high. Results measured by visual inspection and effect size revealed positive acquisition and generalization effects for both participants. Generalization occurred across vowel contexts and to untreated probes. Results of the frequency manipulation were confounded by presentation order. Maintenance of learned and generalized effects were demonstrated for 1 participant. These data provide support for the role of augmented feedback in treating speech movements that result in perceptually accurate speech production. Future investigations will explore the independent contributions of each feedback type (i.e. kinematic and perceptual) in producing efficient and effective training of SMTs in persons with AOS.


Subject(s)
Apraxias/therapy , Articulation Disorders/therapy , Feedback, Psychological , Feedback, Sensory , Language Disorders/therapy , Speech Therapy/methods , Adult , Aphasia/etiology , Aphasia/physiopathology , Apraxias/etiology , Apraxias/physiopathology , Apraxias/psychology , Articulation Disorders/etiology , Articulation Disorders/physiopathology , Articulation Disorders/psychology , Biomechanical Phenomena , Feedback, Sensory/physiology , Female , Humans , Language Disorders/etiology , Language Disorders/physiopathology , Language Disorders/psychology , Learning , Male , Middle Aged , Observer Variation , Online Systems , Phonetics , Psychomotor Performance , Reproducibility of Results , Speech Intelligibility , Speech Production Measurement/instrumentation , Stroke/complications
10.
New Phytol ; 186(1): 135-47, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20074093

ABSTRACT

Allopolyploidy is a major driving force in plant evolution and can induce rapid structural changes in the hybrid genome. As major components of plant genomes, transposable elements are involved in these changes. In a previous work, we observed turnover of retrotransposon insertions in natural allotretraploid tobacco (Nicotiana tabacum). Here, we studied the early stages of allopolyploid formation by monitoring changes at retrotransposon insertion sites in the Th37 synthetic tobacco. We used sequence-specific amplification polymorphism (SSAP) to study insertion patterns of two populations of the Tnt1 retrotransposon in Th37 S4 generation plants, and characterized the nature of polymorphic insertion sites. We observed significant amplification of young Tnt1 populations. Newly transposed copies were amplified from maternal elements and were highly similar to Tnt1A tobacco copies amplified in response to microbial factors. A high proportion of paternal SSAP bands were not transmitted to the hybrid, corresponding to various rearrangements at paternal insertion sites, including indels or the complete loss of the Tnt1/flanking junction. These data indicate that major changes, such as retrotransposon amplification and molecular restructuring in or around insertion sites, occur rapidly in response to allopolyploidy.


Subject(s)
Nicotiana/genetics , Polyploidy , Retroelements/genetics , Base Sequence , Chromosome Segregation/genetics , Crosses, Genetic , Molecular Sequence Data , Mutagenesis, Insertional/genetics , Phylogeny , Polymorphism, Genetic , Sequence Alignment
11.
Expert Opin Pharmacother ; 9(6): 887-900, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18377333

ABSTRACT

BACKGROUND: Over the past 10 years clinical trials aimed at finding suitable neuroprotectants against the debilitating effects of stroke have met with no success. Identifying novel neuroprotectants that can reverse the effects of stroke is becoming a challenge to both clinicians and scientists. OBJECTIVES: This review focused on the current status on the topic and highlights some of the neuroprotectants that are worth examining or re-examining further. METHODS: Recent findings on the subject have been included. CONCLUSION: Many neuroprotectants that have worked in preclinical evaluations have been found to be ineffective in clinical trials. Nevertheless, some of them are still considered to be worth re-examining. Non-coding small RNAs (riboregulators) as novel therapeutic leads have also been introduced in this review.


Subject(s)
Neuroprotective Agents/therapeutic use , Stroke/drug therapy , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Clinical Trials as Topic , Excitatory Amino Acid Antagonists/pharmacology , Excitatory Amino Acid Antagonists/therapeutic use , GABA Agonists/pharmacology , GABA Agonists/therapeutic use , Humans , Hypothermia, Induced , Ion Channel Gating , Ion Channels/agonists , Ion Channels/antagonists & inhibitors , Magnesium Compounds/pharmacology , Magnesium Compounds/therapeutic use , Narcotic Antagonists , Neuroprotective Agents/pharmacology , Nootropic Agents/pharmacology , Nootropic Agents/therapeutic use , Stroke/physiopathology , Stroke/therapy
12.
Ann Bot ; 101(6): 805-14, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18222910

ABSTRACT

BACKGROUND: In studies looking at individual polyploid species, the most common patterns of genomic change are that either genome size in the polyploid is additive (i.e. the sum of parental genome donors) or there is evidence of genome downsizing. Reports showing an increase in genome size are rare. In a large-scale analysis of 3008 species, genome downsizing was shown to be a widespread biological response to polyploidy. Polyploidy in the genus Nicotiana (Solanaceae) is common with approx. 40 % of the approx. 75 species being allotetraploid. Recent advances in understanding phylogenetic relationships of Nicotiana species and dating polyploid formation enable a temporal dimension to be added to the analysis of genome size evolution in these polyploids. METHODS: Genome sizes were measured in 18 species of Nicotiana (nine diploids and nine polyploids) ranging in age from <200,000 years to approx. 4.5 Myr old, to determine the direction and extent of genome size change following polyploidy. These data were combined with data from genomic in situ hybridization and increasing amounts of information on sequence composition in Nicotiana to provide insights into the molecular basis of genome size changes. KEY RESULTS AND CONCLUSIONS: By comparing the expected genome size of the polyploid (based on summing the genome size of species identified as either a parent or most closely related to the diploid progenitors) with the observed genome size, four polyploids showed genome downsizing and five showed increases. There was no discernable pattern in the direction of genome size change with age of polyploids, although with increasing age the amount of genome size change increased. In older polyploids (approx. 4.5 million years old) the increase in genome size was associated with loss of detectable genomic in situ hybridization signal, whereas some hybridization signal was still detected in species exhibiting genome downsizing. The possible significance of these results is discussed.


Subject(s)
Evolution, Molecular , Genome, Plant , Nicotiana/genetics , Polyploidy , DNA, Plant/chemistry , DNA, Plant/genetics , In Situ Hybridization , Nucleic Acid Conformation , Phylogeny
15.
New Phytol ; 166(1): 291-303, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15760371

ABSTRACT

Nicotiana tabacum (tobacco, 2n = 4x = 48) is a natural allotetraploid combining two ancestral genomes closely related to modern Nicotiana sylvestris and Nicotiana tomentosiformis. Here we examine the immediate consequences of allopolyploidy on genome evolution using 20 S4-generation plants derived from a single synthetic, S0 plant made by Burk in 1973 (Th37). Using molecular and cytogenetic methods we analysed 14 middle and highly repetitive sequences that together total approximately 4% of the genome. Two repeats related to endogenous geminiviruses (GRD5) and pararetroviruses (NtoEPRV), and two classes of satellite repeats (NTRS, A1/A2) were partially or completely eliminated at variable frequency (25-60%). These sequences are all from the N. tomentosiformis parent. Genomic in situ hybridization revealed additivity in chromosome numbers in two plants (2n = 48), while a third was aneuploid for an N. tomentosiformis-origin chromosome (2n = 49). Two plants had homozygous translocations between chromosomes of the S- and T-genomes. * The data demonstrate that genetic changes in synthetic tobacco were fast, targeted to the paternal N. tomentosiformis-donated genome, and some of the changes showed concordance with changes that presumably occurred during evolution of natural tobacco.


Subject(s)
DNA, Plant/genetics , Nicotiana/genetics , Polyploidy , Biological Evolution , Crosses, Genetic , DNA, Plant/analysis , DNA, Ribosomal , DNA, Viral/genetics , Genome, Plant , Interspersed Repetitive Sequences , Karyotyping , Plant Viruses/genetics , Tandem Repeat Sequences
16.
Cytogenet Genome Res ; 109(1-3): 298-309, 2005.
Article in English | MEDLINE | ID: mdl-15753590

ABSTRACT

Nicotiana rustica (2n = 4x = 48) is a natural allotetraploid composed of P and U genomes which are closely related to genomes of diploid species N. paniculata and N. undulata. Genomic in situ hybridization (GISH) also confirms that the diploid parents, or close relatives, are the ancestors of N. rustica. In order to study genetic interactions between ancestral genomes in the allotetraploid, we isolated three families of repetitive sequences, two from N. paniculata (NPAMBE and NPAMBO) and one from N. undulata (NUNSSP). Southern blot hybridization revealed that the sequences are digested with a range of restriction enzymes into regular ladder patterns indicating a tandem arrangement of high copy repeats possessing monomeric units of about 180 bp. The three-tandem sequences belong to a larger Nicotiana tandem repeat family called here the HRS-60 family. Members of this family are found in all Nicotiana species studied. Fluorescence in situ hybridization (FISH) analysis localized the satellite repeats to subtelomeric regions of most chromosomes of N. paniculata and N. undulata. The pattern of sequence distribution on the P- and U-genomes of N. rustica was similar to the putative parents N. paniculata and N. undulata respectively. However, NPAMBO repeats appear to be reduced and rearranged in N. rustica that may suggest evolution within the P genome. GISH and FISH with the tandem repeat probes failed to reveal intergenomic translocations as might be predicted from the nucleocytoplasmic interaction hypothesis.


Subject(s)
Diploidy , Evolution, Molecular , Nicotiana/classification , Nicotiana/genetics , Polyploidy , Chromatin/genetics , Chromatin/ultrastructure , Cloning, Molecular , DNA, Plant/genetics , DNA, Ribosomal/genetics , DNA, Satellite/genetics , RNA, Plant/genetics , RNA, Ribosomal, 18S/genetics , Repetitive Sequences, Nucleic Acid , Species Specificity
17.
Heredity (Edinb) ; 94(5): 501-6, 2005 May.
Article in English | MEDLINE | ID: mdl-15770234

ABSTRACT

In Rosa canina (2n = 5x = 35), the pollen and ovular parents contribute, respectively, seven and 28 chromosomes to the zygote. At meiosis I, 14 chromosomes form seven bivalents and 21 chromosomes remain as univalents. Fluorescent in situ hybridization to mitotic and pollen mother cells (PMC) of R. canina showed that 10 chromosomes (two per genome) carry ribosomal DNA (rDNA) loci. Five chromosomes carry terminal 18S-5.8S-26S rDNA loci; three of these also carry paracentric 5S rDNA loci and were designated as marker chromosomes 1. Five chromosomes carry only 5S rDNA loci and three of these were designated as marker chromosomes 2. The remaining four of the 10 chromosomes with rDNA loci were individually identifiable by the type and relative sizes of their rDNA loci and were numbered separately. At PMC meiosis, two marker chromosomes 1 and two marker chromosomes 2 formed bivalents, whereas the others were unpaired. In a gynogenetic haploid of R. canina (n = 4x = 28), obtained after pollination with gamma-irradiated pollen, chromosomes at meiosis I in PMC remained predominantly unpaired. The data indicate only one pair of truly homologous genomes in R. canina. The 21 unpaired chromosomes probably remain as univalents through multiple generations and do not recombine. The long-term evolutionary consequence for the univalents is likely to be genetic degradation through accumulated mutational change as in the mammalian Y chromosome and chromosomes of asexual species. But there is no indication that univalents carry degenerate 5S rDNA families. This may point to a recent evolution of the R. canina meiotic system.


Subject(s)
DNA, Ribosomal/analysis , Meiosis , Polyploidy , Rosa/genetics , Chromosome Banding , Chromosomes, Plant , DNA, Plant/analysis , Gamma Rays , In Situ Hybridization, Fluorescence , Mitosis , Pollen , RNA, Ribosomal, 18S , RNA, Ribosomal, 28S , RNA, Ribosomal, 5.8S , Rosa/radiation effects
18.
Genetics ; 169(2): 931-44, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15654116

ABSTRACT

We investigated concerted evolution of rRNA genes in multiple populations of Tragopogon mirus and T. miscellus, two allotetraploids that formed recurrently within the last 80 years following the introduction of three diploids (T. dubius, T. pratensis, and T. porrifolius) from Europe to North America. Using the earliest herbarium specimens of the allotetraploids (1949 and 1953) to represent the genomic condition near the time of polyploidization, we found that the parental rDNA repeats were inherited in roughly equal numbers. In contrast, in most present-day populations of both tetraploids, the rDNA of T. dubius origin is reduced and may occupy as little as 5% of total rDNA in some individuals. However, in two populations of T. mirus the repeats of T. dubius origin outnumber the repeats of the second diploid parent (T. porrifolius), indicating bidirectional concerted evolution within a single species. In plants of T. miscellus having a low rDNA contribution from T. dubius, the rDNA of T. dubius was nonetheless expressed. We have apparently caught homogenization of rDNA repeats (concerted evolution) in the act, although it has not proceeded to completion in any allopolyploid population yet examined.


Subject(s)
DNA, Ribosomal/genetics , Evolution, Molecular , Nuclear Matrix/chemistry , Polyploidy , Tragopogon/genetics , Chromosomes, Plant , DNA, Plant , Diploidy , Genes, rRNA , Genetics, Population , Genome, Plant , Geography , In Situ Hybridization, Fluorescence , Molecular Sequence Data , Polymorphism, Single-Stranded Conformational , Restriction Mapping , Seeds/growth & development , Tragopogon/cytology , Tragopogon/growth & development
19.
Med J Malaysia ; 60(5): 647-9, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16515119

ABSTRACT

Anaesthetizing patients with Long QT Syndrome is a major challenge, as the potential for sudden catastrophic cardiovascular collapse is well known. We present a 15-year-old boy with Long QT Syndrome who presented for an elective renal transplant. All electrolyte concentration abnormalities were corrected preoperative and adequate beta-blockade was maintained. The patient was given a target controlled infusion of propofol, together with opioids and atracurium. Anaesthesia was uneventful and the patient was extubated at the end of the surgical procedure.


Subject(s)
Anesthesia, General/methods , Kidney Failure, Chronic/surgery , Kidney Transplantation , Long QT Syndrome/surgery , Adolescent , Analgesics, Opioid/administration & dosage , Anesthetics, Intravenous/administration & dosage , Humans , Male , Neuromuscular Nondepolarizing Agents/administration & dosage
20.
Med J Malaysia ; 60(4): 432-40, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16570704

ABSTRACT

The objective of this survey was to obtain a self-reported assessment of the use of information technology (IT) by final year medical students. Two hundred and sixty five students responded to a questionnaire survey. 81.5% of students considered their computer skills adequate, while 87.9% had access to computers outside the campus. Most students reported adequate skills at word processing, e-mailing and surfing the Internet. Fifty three percent of students spent three hours or more each week on the computer. While students indicated a general willingness to access Internet-based materials, further steps need to be taken to increase the use of this method of instruction.


Subject(s)
Computer Literacy , Education, Medical, Undergraduate/organization & administration , Information Systems/statistics & numerical data , Internet/statistics & numerical data , Medical Informatics/education , Perception , Schools, Medical , Students, Medical/psychology , Data Collection , Electronic Data Processing/statistics & numerical data , Electronic Mail/statistics & numerical data , Humans , Malaysia , Surveys and Questionnaires
SELECTION OF CITATIONS
SEARCH DETAIL
...