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1.
Nature ; 602(7898): 585-589, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35197615

RESUMO

Fast radio bursts (FRBs) are flashes of unknown physical origin1. The majority of FRBs have been seen only once, although some are known to generate multiple flashes2,3. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission4,5. Recently, the discovery6 of another repeater (FRB 20200120E) was announced, in the direction of the nearby galaxy M81, with four potential counterparts at other wavelengths6. Here we report observations that localized the FRB to a globular cluster associated with M81, where it is 2 parsecs away from the optical centre of the cluster. Globular clusters host old stellar populations, challenging FRB models that invoke young magnetars formed in a core-collapse supernova. We propose instead that FRB 20200120E originates from a highly magnetized neutron star formed either through the accretion-induced collapse of a white dwarf, or the merger of compact stars in a binary system7. Compact binaries are efficiently formed inside globular clusters, so a model invoking them could also be responsible for the observed bursts.

2.
Malays Orthop J ; 15(1): 135-137, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33880162

RESUMO

The optimisation of blood pressure management is critical in managing hypotensive episodes in patients with spinal cord injury. Improper handling of this preventable factor will negatively impact the patient recovery prognosis. A 42-year-old man was admitted for a complete spinal cord injury after fell from height. He developed subacute neurological deterioration unrelated to the mechanical instability but due to multiple episodes of hypotension occurring one month after the initial injury. After proper management of blood pressure, his deterioration was halted and no further progression. Spinal cord haemodynamics play an important role in mediating the onset of subacute post-traumatic ascending myelopathy. Better education and awareness on Subacute Post-traumatic Ascending Myelopathy (SPAM) especially to the junior healthcare providers are important to hinder this rare but avoidable condition.

3.
Qatar Med J ; 2020(1): 2, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32166070

RESUMO

Background: Obesity has always been considered a criterion of difficult airway management, and many authors have tackled this subject. We are presenting our experience in airway management in obese patients undergoing bariatric surgery in Qatar and comparing the results with previous studies. Objective: The primary objective of this study was to explore the relationship between difficult mask ventilation and difficult intubation. The secondary objective was to identify other factors that may play a role in either difficulty such as gender, associated comorbidities, and the skill and experience of anesthetists. Design: This study was a prospective observational cohort study. Sample: A total of 401 patients were selected for various elective bariatric surgery in Hamad General Hospital, including 130 males and 271 females with an average body mass index(BMI) of 46.03 kg m- 2. Results: We used Pearson Chi-Square and Yates corrected Chi-square statistical tests in our statistical analysis. Neck circumference had a p value of 0.001 in both genders. The male gender had a p value of 0.052 and 0.012 in mask ventilation and difficult intubation, respectively. The Mallampati score had a p value of 0.56 and 0.006 in mask ventilation and intubation, respectively. In general, neck circumference, Mallampati score, gender, obstructive sleep apnea, and diabetes mellitus had greater negative effects on airway management than BMI alone. Conclusion: It was hard to intubate 25% of patients who had difficult mask ventilation (DMV). All DMV and 20 out of 23 of difficult intubation patients were in the high BMI group ( ≥ 40). Neck circumference, Mallampati score, and male gender were major independent factors; however, other factors, such as obstructive sleep apnea, and diabetes mellitus, should be kept in mind as additional risks.

4.
Malays J Pathol ; 40(2): 111-119, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30173227

RESUMO

INTRODUCTION: Thyroid cancer is the most common endocrine malignancy with more than 95% originating from follicular epithelial cells. Diagnostic dilemma may arise in occasional cases such as when an encapsulated nodule with a follicular growth pattern exhibits clear nuclei with grooves making it difficult to distinguish a follicular adenoma from encapsulated follicular variant papillary thyroid carcinoma. This study aimed to evaluate the diagnostic utility of an immunohistochemical marker, CD56, to distinguish between benign and malignant thyroid lesions. MATERIALS AND METHODS: We retrospectively studied CD56 expression in 54 benign and 54 malignant thyroid lesions using archival formalin fixed paraffin-embedded tissue blocks for the study period from January 2010 to December 2015, diagnosed in a tertiary hospital. RESULTS: CD56 was expressed in 52/54 (96.3%) of benign specimens and only 24/54 (44.4%) of malignant ones. The malignant specimens comprised 31 (57.4%) papillary thyroid carcinomas (PTC), 11 (20.3%) follicular carcinomas (FC), seven (13%) medullary thyroid carcinomas (MC), one (1.9%) poorly differentiated carcinoma (PC) and four (7.4%) anaplastic carcinomas (AC). CD56 was not expressed in 28/31 (90.3%) of the PTCs, 1/11 (9.1%) FCs, 1/4 (25%) of ACs while all MCs and the PD were positive. The benign group comprised nodular hyperplasias (29/54), lymphocytic thyroiditis (10/54), follicular adenomas (FA) (14/54) and one hyalinising trabecular tumour. CD56 was expressed in all the benign cases except one FA and one nodular hyperplasia. Thirteen of the 14 FAs were CD56 positive. The difference in expression between benign and malignant tumours was statistically significant as the p value was <0.01. CONCLUSION: CD56 is a potentially good immunohistochemical marker for differentiating papillary thyroid carcinoma from other benign follicular lesions of the thyroid especially in differentiating follicular variant PTC from FA in equivocal cases.


Assuntos
Adenoma/patologia , Biomarcadores Tumorais/análise , Antígeno CD56/biossíntese , Neoplasias da Glândula Tireoide/patologia , Adenoma/diagnóstico , Adulto , Antígeno CD56/análise , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico
5.
Trop Biomed ; 35(4): 1049-1063, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601852

RESUMO

The medically important mosquito, Aedes albopictus is native to Asia and has become a major health concern in most Asian countries including Malaysia. Being recognized as a dengue vector, a clearer understanding of how mosquito populations are geographically connected, may therefore represent a profound yet significant understanding of control strategies. There are no documented reports on the genetic structure of Ae. albopictus populations from different developed settlements inferred from microsatellite DNA markers in Malaysia, particularly in Penang Island (Northern Peninsular Malaysia). Here, we assessed the molecular population genetics of Ae. albopictus in terms of their allelic variation, genetic diversity and population structure. A total of 42 mosquitoes were sampled from Jelutong, Batu Maung and Balik Pulau which represented urban, suburban and rural areas in Penang Island respectively and analysed for polymorphism at six microsatellite loci. All of the microsatellite markers were successfully amplified and were polymorphic, showing low genetic structure among geographic populations (FST= 0.0362). It is supported with admixture individuals observed in STRUCTURE and FCA and this suggests that high gene flow has been experienced between populations. These findings implicate passive dispersal through human-aided transportation; as a factor shaping the genetic structure of Ae. albopictus populations in Penang Island.

6.
Tropical Biomedicine ; : 1049-1063, 2018.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-751357

RESUMO

@#The medically important mosquito, Aedes albopictus is native to Asia and has become a major health concern in most Asian countries including Malaysia. Being recognized as a dengue vector, a clearer understanding of how mosquito populations are geographically connected, may therefore represent a profound yet significant understanding of control strategies. There are no documented reports on the genetic structure of Ae. albopictus populations from different developed settlements inferred from microsatellite DNA markers in Malaysia, particularly in Penang Island (Northern Peninsular Malaysia). Here, we assessed the molecular population genetics of Ae. albopictus in terms of their allelic variation, genetic diversity and population structure. A total of 42 mosquitoes were sampled from Jelutong, Batu Maung and Balik Pulau which represented urban, suburban and rural areas in Penang Island respectively and analysed for polymorphism at six microsatellite loci. All of the microsatellite markers were successfully amplified and were polymorphic, showing low genetic structure among geographic populations (FST= 0.0362). It is supported with admixture individuals observed in STRUCTURE and FCA and this suggests that high gene flow has been experienced between populations. These findings implicate passive dispersal through human-aided transportation; as a factor shaping the genetic structure of Ae. albopictus populations in Penang Island.

7.
Science ; 358(6370): 1579-1583, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29038372

RESUMO

Gravitational waves have been detected from a binary neutron star merger event, GW170817. The detection of electromagnetic radiation from the same source has shown that the merger occurred in the outskirts of the galaxy NGC 4993, at a distance of 40 megaparsecs from Earth. We report the detection of a counterpart radio source that appears 16 days after the event, allowing us to diagnose the energetics and environment of the merger. The observed radio emission can be explained by either a collimated ultrarelativistic jet, viewed off-axis, or a cocoon of mildly relativistic ejecta. Within 100 days of the merger, the radio light curves will enable observers to distinguish between these models, and the angular velocity and geometry of the debris will be directly measurable by very long baseline interferometry.

8.
Eur J Dent Educ ; 18(1): 51-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24423176

RESUMO

Training dentists today is challenging as they are expected to provide a wide range of dental care. In the provision of good dental care, soft skills are equally important as clinical skills. Therefore in dental education the development of soft skills are of prime concern. This study sought to identify the development of soft skills when dental students are paired in their clinical training. In this perception study, four open-ended items were used to elicit students' feedback on the appropriateness of using clinical pairing as an instructional strategy to promote soft skills. The most frequently cited soft skills were teamwork (70%) and communication (25%) skills. However, both negative and positive behaviours were reported. As for critical thinking and problem solving skills, more positive behaviours were reported for abilities such as to explain, analyze, find ideas and alternative solutions, and make decisions. Leadership among peers was not evident as leading without legitimate authority could be a hindrance to its development. If clinical pairing is to be used as an effective instructional strategy to promote soft skills amongst students, clear guidelines need to be developed to prepare students to work in a dental team and the use of appropriate assessment tools can facilitate the development of these soft skills.


Assuntos
Competência Clínica , Educação em Odontologia/métodos , Comunicação , Tomada de Decisões , Ética Odontológica , Feminino , Humanos , Liderança , Masculino , Princípios Morais , Equipe de Assistência ao Paciente , Resolução de Problemas , Inquéritos e Questionários , Pensamento
9.
Bratisl Lek Listy ; 111(10): 562-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21125803

RESUMO

BACKGROUND: Atlanto-occipital fusion may be symptomatic or asymptomatic in nature. The anomaly may be incidentally detected at autopsies or during routine cadaveric dissections. The fusion of the atlas with occipital bone may result in the compression of vertebral artery and first cervical nerve. METHODS: A total of 55 dried occipital bones in the Department of Anatomy, Universiti Kebangsaan Malaysia (UKM) and Department of Anatomy, Universiti Malaya (UM) were included in the study. The presence of atlantooccipital fusion was closely observed and morphometric measurements were taken. RESULTS: Out of 55 dried occipital bones studied, we observed atlanto-occiptalization in two bones (3.63 %). A total of 53 occipital bones (96.37 %) did not exhibit any anomalous fusions. Out of the two anomalous atlanto-occiptal fusions, one was complete while the other had unilateral right-sided fusion of the atlas with the occipital bone. CONCLUSION: Atlanto-occipitalization may result in the compression of vertebral artery thereby influencing the blood flow to the brain. Atlanto-occipitalization may also result in compression of the first cervical nerve. The action of the postural muscles on the extensor surface may be affected as a result of this anomaly. The present article discusses the clinical implications of atlanto-occipitalization, which may be beneficial for neurosurgeons, neurologists and radiologists in day-to-day clinical practice (Fig. 3, Ref. 17).


Assuntos
Articulação Atlantoccipital/anormalidades , Humanos , Osso Occipital/patologia , Sinostose/patologia
10.
Neuroimage ; 34(2): 671-8, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17123835

RESUMO

INTRODUCTION: Brain imaging studies have linked the anterior cingulate cortex (ACC) to motivation, drive, and personality traits like novelty and sensation seeking. Animal studies have shown glutamatergic neurotransmission to be important in ACC function as well as motivated behaviour. However, the role of glutamate in related personality traits like sensation seeking has not been investigated in humans. METHODS: The associations between sensation seeking personality scores and absolute glutamate concentrations in the ACC and the hippocampal region measured by 3-Tesla proton magnetic resonance spectroscopy (1H-MRS) were investigated. RESULTS: ACC glutamate concentration was negatively correlated with the sensation seeking sum score and the experience seeking subscore. A weak negative correlation was also observed between the hippocampal glutamate and the sensation seeking sum score. The reexamination of the glutamate concentration after 4 weeks revealed a similar relationship with sensation seeking. DISCUSSION: Although preliminary, the results are in line with the key role of the ACC for motivation and executive control and with the impact of glutamate on novelty related behaviour observed in animal experiments. The role of the hippocampus for novelty processing is discussed. Glutamate measurement with 1H-MRS may facilitate the understanding of biological underpinnings of personality traits and psychiatric diseases associated with dysfunctions in motivation and drive.


Assuntos
Comportamento/fisiologia , Química Encefálica/fisiologia , Córtex Cerebral/química , Ácido Glutâmico/análise , Personalidade/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
13.
Scand J Infect Dis ; 33(3): 215-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11303813

RESUMO

Several studies have suggested high predictive values of serum procalcitonin (PCT) for the discrimination of bacterial and viral meningitis in children and adults. Here, we report PCT serum concentrations in 12 adults suffering from bacterial meningitis. PCT on admission was normal ( < or = 500 pg/ml) in 3 and between 500 and 1,000 pg/ml in 2 patients without evidence of concurrent bacterial infections. Conversely, in 5 patients with PCT concentrations between 2,268 and 38,246 pg/ml other infections were present. PCT concentrations were higher with typical meningitis agents (pneumococci and meningococci 12,679 +/- 13,092 pg/ml vs. other bacteria 4048 +/- 9187 pg/ml, p = 0.041) whilst in nosocomial bacterial meningitis after neurosurgery (n = 3) serum PCT remained normal. We believe that PCT is of limited diagnostic value in adults suffering from bacterial meningitis, especially in cases due to unusual agents or of nosocomial origin. Elevated PCT in bacterial meningitis may indicate the presence of bacterial inflammation outside the central nervous system.


Assuntos
Calcitonina/sangue , Meningites Bacterianas/sangue , Precursores de Proteínas/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Peptídeo Relacionado com Gene de Calcitonina , Infecção Hospitalar/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Contagem de Leucócitos , Masculino , Meningites Bacterianas/diagnóstico , Meningite Viral/sangue , Meningite Viral/diagnóstico , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Vet Hum Toxicol ; 39(6): 337-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9397501

RESUMO

A modified method was compared with an original electrometric method for measurement of erythrocyte acetylcholinesterase (EChE) activity in sheep. The mean +/- SD (pH/30 min) of EChE activity of 8 sheep measured by the modified procedure (0.70 +/- 0.15) was not significantly different from that of the original method (0.64 +/- 0.12). The inherently low plasma cholinesterase activity of the sheep as measured by the 2 methods were also not significantly different from each other (0.09 +/- 0.04 vs 0.10 +/- 0.04). The coefficient of variation of the modified method in measuring EChE activity was 8%. The method was used to demonstrate in vitro inhibition of sheep EChE activity by the organophosphorus and carbamate insecticides dichlorvos and methomyl, respectively. The method could be well-suited for rapid measurement of EChE activity in sheep, especially in cases of organophosphate and possibly carbamate poisoning.


Assuntos
Acetilcolinesterase/sangue , Eritrócitos/enzimologia , Animais , Inibidores da Colinesterase/farmacologia , Diclorvós/farmacologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Metomil/farmacologia , Ovinos
15.
J Anat ; 190 ( Pt 4): 577-88, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9183680

RESUMO

Exposure of male Albino Swiss rats to the nonsteroidal antiandrogen flutamide during the period from gestational day (d) 10 to birth resulted in feminisation of the external genitalia and the suppression of growth of the male reproductive tract. In adulthood, testes were found to be located in diverse positions. True cryptorchidism occurred in 10% of cases, whereas 50% of testes descended to the scrotum and 40% were located in a suprainguinal ectopic region. Varying degrees of tubule abnormality were seen in the testes of flutamide-treated animals, ranging from completely normal tubules with full spermatogenesis (and the expected frequency of the stages of spermatogenesis) to severely abnormal tubules lined with Sertoli cells only. For each individual testis, the overall severity of tubule damage was strongly correlated with its adult location, with intra-abdominal testes worst affected and scrotally-located testes least; only the latter contained normal tubules. Similarly, intra-abdominal testes were the smallest in weight and contained the least testosterone. By contrast, postnatal treatment of male rats with flutamide from birth to postnatal d 14 did not impair development of the external genitalia, the process of testicular descent or adult spermatogenesis. These findings confirm that androgen blockade during embryonic development interferes with testicular descent but also demonstrate that (1) prenatal flutamide treatment per se has a detrimental effect on adult testis morphology but (2) the degree of abnormality of the testes is strongly influenced by location.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Feminização/induzido quimicamente , Flutamida/efeitos adversos , Testículo/efeitos dos fármacos , Testículo/embriologia , Antagonistas de Androgênios/farmacologia , Animais , Criptorquidismo/induzido quimicamente , Criptorquidismo/patologia , Feminização/patologia , Flutamida/farmacologia , Idade Gestacional , Masculino , Ratos , Ratos Endogâmicos , Testículo/patologia
16.
Toxicology ; 58(1): 91-5, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2815094

RESUMO

Male mice were treated orally with the organophosphorus insecticides fenamiphos and dichlorvos at 10 and 150 mg/kg, respectively. The insecticides produced signs of toxicosis characteristic of cholinesterase inhibition, and induced death in all treated mice. Pretreatment of mice with diphenhydramine HCl (20 and 30 mg/kg, subcutaneously) 15 min before either insecticide significantly (P less than 0.05) reduced the incidence of toxic manifestations (excessive salivation, Straub tail, and whole body tremor), delayed the onset of death, and increased the percentage of survivors. Doses of diphenhydramine less than 20 mg/kg were not so effective. The data indicated a protective property of diphenhydramine against organophosphorus insecticide-induced toxicosis.


Assuntos
Diclorvós/toxicidade , Difenidramina/farmacologia , Inseticidas/toxicidade , Compostos Organofosforados/toxicidade , Animais , Inibidores da Colinesterase/toxicidade , Antagonismo de Drogas , Masculino , Camundongos , Salivação/efeitos dos fármacos , Tremor/prevenção & controle
17.
Vet Hum Toxicol ; 31(1): 13-5, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2711602

RESUMO

Intraperitoneal (ip) administration of xylazine (1-6 mg/kg) in male rats significantly increased urine flow over a 2-hr period in a dose-dependent manner, while urine osmolality was significantly decreased. Xylazine at 4.5 and 6 mg/kg significantly increased sodium excretion, whereas the 3 and 6 mg/kg doses of xylazine significantly increased potassium excretion. Yohimbine injected ip at 0.5 or 1 mg/kg 15 min before xylazine (6 mg/kg, ip) significantly decreased urine flow by 44% and 64% respectively. Yohimbine also prevented the increase in sodium and potassium excretion induced by xylazine. The data indicate that yohimbine is of value in controlling the diuretic effect of xylazine in rats.


Assuntos
Diurese/efeitos dos fármacos , Tiazinas/farmacologia , Xilazina/farmacologia , Ioimbina/farmacologia , Animais , Masculino , Concentração Osmolar , Potássio/urina , Ratos , Sódio/urina
18.
Toxicol Lett ; 37(3): 235-40, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3617097

RESUMO

Physostigmine (1.5 mg/kg, s.c.) and neostigmine (1.0 mg/kg, s.c.) injection into male mice produced signs of toxicosis characteristic of cholinesterase inhibition and evoked death in 95 and 94% of the animals respectively. Diphenhydramine injections (5-30 mg/kg, s.c.) 15 min before physostigmine or neostigmine significantly increased the latency period to onset of death and the percentage of survivors. Diphenhydramine injection (20 mg/kg, s.c.) between -30 and +2 min (but not at +5 and +10 min) relative to physostigmine prevented lethality in 100% of the animals. The data indicated that diphenhydramine which possesses anticholinergic effects protected mice against physostigmine- and neostigmine-induced toxicosis.


Assuntos
Inibidores da Colinesterase/antagonistas & inibidores , Difenidramina/farmacologia , Animais , Inibidores da Colinesterase/intoxicação , Sinergismo Farmacológico , Dose Letal Mediana , Masculino , Camundongos , Neostigmina/antagonistas & inibidores , Fisostigmina/antagonistas & inibidores
19.
J Am Diet Assoc ; 87(5): 584-92, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3571775

RESUMO

A system for reporting dietary data in terms of food groups is described. The scheme was developed jointly by the National Heart, Lung, and Blood Institute (NHLBI) and the U.S. Department of Agriculture to identify food use patterns in various population groups. The system comprises 14 major groups and 75 minor groups based on major nutrient composition with special attention to fats. One-day dietary recalls from 5,640 participants in the Lipid Research Clinics (LRC) Prevalence Study were analyzed to determine the frequency of food group usage by males and females in age groups 6 to 9, 10 to 19, 20 to 59, and 60 and older. Food group use is reported as percent of the population reporting use as obtained by the dietary recall as well as the average number of times each food group was mentioned by the users. LRC food selection patterns are compared with the Dietary Guidelines. Findings in this report indicate that, for the LRC population, some of the foods emphasized in the guidelines are not eaten with a high degree of frequency.


Assuntos
Gorduras na Dieta/classificação , Alimentos , Adolescente , Adulto , Criança , Comportamento Alimentar , Feminino , Análise de Alimentos/métodos , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Am Diet Assoc ; 79(5): 552-4, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7288061

RESUMO

Forty different brands of chocolate candies were purchased in a supermarket. The wrappers were removed and coded, and the candy was re-wrapped in aluminum foil until analyzed. More than 60 percent of the samples had a polyunsaturated/saturated (P/S) ratio of less than 0.10. Although the candies examined had a higher carbohydrate than fat content, fat frequently contributed more calories in the candies containing more than 25 percent fat (15 of the 40 brands studied).


Assuntos
Cacau/análise , Doces/análise , Gorduras/análise , Ácidos Graxos/análise , Carboidratos/análise
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