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1.
Hong Kong Med J ; 29(4): 360-362, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37489276
2.
Hong Kong Med J ; 28(6): 447-456, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36423912

RESUMEN

INTRODUCTION: This retrospective study was conducted to identify the characteristics of paediatric high-grade osteosarcoma and define its prognostic factors. METHODS: We identified paediatric patients (aged <19 years at diagnosis) diagnosed with high-grade osteosarcoma from 1 January 2009 to 31 December 2018 in two hospitals in Hong Kong, then retrospectively evaluated their medical records to identify prognostic factors. RESULTS: In total, 52 patients were included in this study (22 girls, 42.3%). Femoral tumour was the most common form of osteosarcoma. Most patients (78.8%) had localised disease at diagnosis. The lung was the most common site of metastasis. Almost half (n=23, 46.9%) of the patients showed a good response to chemotherapy (ie, chemonecrosis >90%). Most patients (n=40, 80%) underwent limb-salvage surgery. The event-free survival and overall survival rates were 55.8% and 71.2%, respectively. Prognostic factors independently associated with poor event-free survival and poor overall survival were the presence of metastasis at diagnosis, poor tumour chemonecrosis, and the need for amputation. CONCLUSION: This multicentre review of paediatric high-grade osteosarcoma showed that the baseline patient demographics, event-free survival, and overall survival in Hong Kong were similar to previous findings in other countries. Patients with metastatic disease at diagnosis and poor chemonecrosis had worse survival outcomes. Molecular analyses of genetic abnormalities may help to identify targeted therapies in future studies.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Femenino , Niño , Humanos , Estudios Retrospectivos , Neoplasias Óseas/patología , Pronóstico , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Tasa de Supervivencia
3.
4.
Hong Kong Med J ; 28(5): 344-346, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38232962
5.
Cyborg Bionic Syst ; 2021: 9861513, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36285143

RESUMEN

As observed in the outbreaks of SARS and swine flu, as well as many other infectious diseases, the huge volume of human traffic across numerous enclosed public venues has posed immense challenges to preventing the spread of communicable diseases. There is an urgent need for effective disease surveillance management in public areas under pandemic outbreaks. The physicochemical properties associated with ionic liquids make them particularly suited for molecular communications in sensing networks where low throughput is quite adequate for pathogen detection. This paper presents a self-cognizant system for rapid diagnosis of infectious disease using a bionic sensor such that testing can be supported without collecting a fluid sample from a subject through any invasive methods. The system is implemented for testing the performance of the proposed bionic liquid sensing network.

8.
J Healthc Inform Res ; 4(3): 215-237, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35415448

RESUMEN

Research has shown that cognitive and physical functioning of older adults can be reflected in indicators such as walking speed. While changes in cognition, mobility, or health cause changes in gait speed, often gradual variations in walking speed go undetected until severe problems arise. Discrete clinical assessments during clinical consultations often fail to detect changes in day-to-day walking speeds and do not reflect walking speeds in everyday environments, where most of the mobility issues happen. In this paper, we compare four walking speed measurement technologies to a GAITRite mat (gold standard): (1) an ultra wideband radar (covering the band from 3.3 GHz to 10 GHz), (2) a narrow band 24-GHz radar (with a bandwidth of 250 MHz), (3) a perception Neuron Motion Tracking suit, and (4) a thermal camera. Data were collected in parallel using all sensors at the same time for 10 healthy adults for normal and slow walking paces. A comparison of the sensors indicates better performance at lower gait speeds, with offsets (when compared to GAITRite) between 0.1 and 20% for the ultra wideband radar, 1.9 and 17% for the narrowband radar, 0.1 and 38% for the thermal camera, and 1.7 and 38% for the suit. This paper supports the potential of unobtrusive radar-based sensors and thermal camera technologies for ambient autonomous gait speed monitoring for contextual, privacy-preserving monitoring of participants in the community.

9.
J Dairy Sci ; 98(3): 1411-25, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25557897

RESUMEN

Differing amounts of fresh forage and concentrates fed, and level of input contributes to the differences reported in fatty acid (FA) composition of organic and conventionally produced cow milk. In many previous studies designed to investigate this phenomenon, comparisons were made between grazed organic cows and housed conventional cows. In the present study, we have investigated differences between organic and conventional milk produced using year-round pasture grazing, as practiced in New Zealand. The FA composition was determined in milk sampled at morning and evening milking in both spring and autumn. Samples were taken from 45 cows from the Massey University organic herd and compared with 50 cows from the corresponding conventional herd grazed and managed similarly at the same location. Forty-three out of 51 analyzed FA were influenced by season, whereas 28 were different between production systems. In addition, one-half were also different due to time of milking. Levels of linoleic acid and α-linolenic acid were higher in organic milk, whereas conjugated linoleic acid (CLA) and vaccenic acid were higher in conventional milk. The first 3 FA (linoleic acid, α-linolenic acid, and CLA) were more abundant in milk harvested during autumn, and the CLA concentration was also significantly influenced by time of milking. Our results confirm reports that the FA profile is affected by season and time of milking, and we also showed an effect due to the production system, when both sets of cows were kept continuously on pasture, even after taking milking time and seasonal effect into account.


Asunto(s)
Alimentos Orgánicos , Ácido Linoleico/análisis , Ácidos Linoleicos Conjugados/análisis , Leche/química , Ácidos Oléicos/análisis , Ácido alfa-Linolénico/análisis , Animales , Bovinos , Dieta/veterinaria , Femenino , Lactancia , Nueva Zelanda , Estaciones del Año
10.
Hong Kong Med J ; 19 Suppl 9: 9-11, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24473582

RESUMEN

1. Among university entrants, the prevalence of pathological Internet use (PIU) increased more than three-fold (from 5.0 to 15.7%) after 18 months of university life. Psycho-social factors such as depression, life dissatisfaction, and use of the Internet for recreational purposes were associated with the development of PIU. 2. University health workers should be aware that PIU is associated with inferior mental well-being, increased sleeping disorders, and deterioration of family relationships. Special attention should be given to Mainland Chinese students and those with pre-existing psychological problems, as they are more prone to developing PIU. 3. Most university students with PIU were unaware of the health implications of the condition and thus not motivated to seek help. Health workers must take a pro-active approach.


Asunto(s)
Internet/estadística & datos numéricos , Estudiantes/psicología , Hong Kong , Humanos , Encuestas y Cuestionarios , Universidades
11.
Placenta ; 33(4): 312-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22225907

RESUMEN

OBJECTIVES: Gangliosides are structural and functional glycosphingolipids, considered to have important roles in neuronal development in fetal and neonatal development and in memory formation. In this report, we have investigated the ability of bovine milk-derived gangliosides GM3 and GD3 to cross the human placenta. STUDY DESIGN: We have employed the ex-vivo model of dually-perfused isolated human placental lobules. RESULTS: There was significant uptake of both GD3 and GM3 from the maternal perfusate. There was significant increase of GM3 in the fetal side and a non-statistically significant trend for GD3 to increase on the fetal side. CONCLUSIONS: Hence an apparent preference for GM3 release into fetal circulation. We suggest that gangliosides consumed by the mother enter her circulation, can be transferred across the placenta and may be available to the developing fetus for building neural connections.


Asunto(s)
Gangliósidos/metabolismo , Intercambio Materno-Fetal , Placenta/metabolismo , Transporte Biológico , Cesárea , Femenino , Gangliósido G(M3)/metabolismo , Humanos , Técnicas In Vitro , Modelos Biológicos , Perfusión , Embarazo , Nacimiento a Término
12.
Ultrasound Obstet Gynecol ; 29(5): 590-9, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17427894

RESUMEN

After 35 years of real-time two-dimensional sonography, can we now identify changes in fetal motility indicative of malfunction of the central nervous system in high-risk pregnancies? A literature search on motor assessment procedures (movements specified for body part (SMP), quantity, quality and behavioral state), and motor milestones obtained per fetus (with various congenital disorders) yielded 48 articles describing motility of 104 fetuses. In 67%, SMPs (especially isolated arm or leg movements, breathing and general movements) were assessed. Quantitative aspects were examined in 76%, qualitative aspects in 62% and behavioral states in two fetuses. Abnormal motility can be divided into two main subcategories: hypo- and hyperkinetic, demonstrating decreased variation in qualitative performance (reduced or increased, respectively, amplitude, speed and number of participating body parts, abnormal quantity (reduced or increased, respectively) and reduced differentiation into SMPs. Posture was affected in 40/60 hypokinetic and 4/44 hyperkinetic moving fetuses. The majority of the disorders resulted in an adverse outcome. Fourteen percent survived with a handicap, depending on the underlying disorder. The 16 disorders with hypokinetic motility had mainly an autosomal recessive etiology with no possibility of invasive prenatal diagnosis or conclusive sonographic structural anomalies, in contrast to the 17 disorders with hyperkinetic motility. Within the limitations of the studies, a deeper understanding of affected milestones in motor development can be obtained. Broadening motor assessment procedures from quantitative only to include qualitative aspects, differentiation of SMPs and behavioral states and emphasizing onset and continuity of motility before and after birth will enhance the reliability and predictive value of motility as a parameter in the assessment of fetal condition.


Asunto(s)
Sistema Nervioso Central/anomalías , Movimiento Fetal/fisiología , Sistema Nervioso Central/fisiopatología , Femenino , Desarrollo Fetal/fisiología , Enfermedades Fetales/fisiopatología , Edad Gestacional , Humanos , Hipercinesia/fisiopatología , Hipocinesia/fisiopatología , Actividad Motora/fisiología , Embarazo , Diagnóstico Prenatal/métodos
14.
Ultrasound Obstet Gynecol ; 27(6): 701-11, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16710877

RESUMEN

After 35 years of real-time two-dimensional sonography, and now that 4D sonography is within our grasp, this article presents an overview of present-day knowledge of normal fetal motility. A literature search was carried out on articles from 1970, using the keywords: 'fetal', 'movements', 'motility', 'movement patterns', 'ultrasound' and 'sonography'. Inclusion criteria were human studies and use of real-time sonography. Articles were screened for type of motor assessment procedure, in terms of whether they: specified movements for participating body parts (specific movement pattern, SMP), were qualitative (performance in terms of speed and amplitude), were quantitative, identified behavioral states, stated the duration of observation, and specified gestational age. We noted developmental milestones obtained for each study aim. One of four aims was identified for each article, depending on whether it focused on emergence, development, or continuity after birth of the movement patterns, or on the relationship of various motor aspects to other parameters that evaluate fetal condition, such as blood flow and fetal heart rate. A total of 109 relevant articles was identified, examining 9862 fetuses. Assessment was performed primarily with analysis of SMPs (89%); 52% also included non-SMPs (NSMPs), 78% included quantification, 24% assessment of quality, and 32% behavioral states. The duration of observation was 1 h or longer in 50% of the studies. The focus in 28 studies was on emergence, in 44 it was on development, in five it was on continuity and in 32 it was on relationship of the movements with other parameters of fetal well-being. A few milestones identified were determination of the strictly age-related emergence of SMPs and behavioral states, the highly reproducible quality of SMPs throughout gestation, the age-related trends in quantified SMPs, the continuity in quality and quantity after birth, and the close relationship between motility and heart-rate variability, flow parameters, and behavioral states. Periods of longest inactivity recorded before 20 weeks were 13 min; after 30 weeks they were 45 min. Much insight was obtained into the development of motility and its relationship to other parameters from those articles applying comparable assessment procedures. An assessment procedure with well-defined SMPs, qualitative and quantitative aspects of SMPs and NSMPs, and an observation period dependent on age are advocated for future research.


Asunto(s)
Movimiento Fetal , Femenino , Desarrollo Fetal , Edad Gestacional , Humanos , Actividad Motora , Embarazo , Ultrasonografía Prenatal
15.
Can J Urol ; 12(3): 2713-21, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16011820

RESUMEN

OBJECTIVE: To assess the efficacy of CT angiography (CTA) in evaluating the renovascular anatomy in 50 patients who underwent laparoscopic donor nephrectomy, and to correlate results with donor morbidity and recipient outcome. METHODS: Forty-eight patients were evaluated by CTA prior to laparoscopy. Donors with aberrant renovasculature and their respective recipients were divided into: 1) accurate preoperative CTA ("predictive group", PG), 2) inaccurate CTA ("non-predictive group", NPG). Warm ischemia times (WIT), estimated blood loss (EBL), operative time (OT), and the open conversion rate were compared. Recipient creatinine values on post-operative day 1 and 3 months were recorded with the rate of delayed graft function (DGF) and ureteral complication. Statistical significance was calculated using the student's T-test. RESULTS: Among patients with aberrant vasculature (48%, 23/48) at laparoscopy, 14 were accurately predicted by CT angiography (11 arterial, 3 venous). NPG consisted of 5 duplicated arteries, 1 early arterial branching, and 3 anomalous veins. CT accuracy was 85%. The sensitivity and specificity of the arterial imaging were 65% and 100% respectively, while those of venous imaging were 50% and 100%. EBL, WIT, OT, number of open conversions, and ureteral complications were statistically insignificant between groups (p= 0.05, 95% C.I.). The mean decreases in creatinine between NPG and PG on post-operative day 1 and at 3 months were 45.4% and 54.8%, and 71.5% and 79.1% respectively, both statistically insignificant. Two of 8 in the NPG experienced DGF as compared to 1/8 in the PG. CONCLUSIONS: Despite the lower sensitivity of this study, the discordance between imaging and laparoscopy did not augment donor morbidity or increase adverse recipient outcomes. This may indicate that regardless of the shortcomings of 2-D CTA for living donors, it represents a safe and effective imaging modality when coupled with meticulous laparoscopic dissection and central intraoperative involvement of the transplant surgeon.


Asunto(s)
Trasplante de Riñón/métodos , Riñón/irrigación sanguínea , Laparoscopía , Donadores Vivos , Nefrectomía/métodos , Complicaciones Posoperatorias , Angiografía , Humanos , Riñón/cirugía , Morbilidad , Cuidados Preoperatorios , Pronóstico , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
17.
Ultrasound Obstet Gynecol ; 21(4): 389-92, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12704750

RESUMEN

The Prader-Willi syndrome (PWS) is a complex, multisystem disorder. The syndrome affects the central nervous system, with a predilection for the hypothalamus. The clinical picture in PWS is very variable, and depends on the age of the affected child. Frequently, the most prominent features such as obesity, mental retardation and behavioral disorders do not become evident until the later childhood stage, which can lead to underdiagnosis or late diagnosis in early childhood. Because of the long-term implications of this syndrome, it is important to recognize its features as soon as possible so that early counseling of parents and the affected child is possible. Because PWS can also lead to complications in both pregnancy and labor, proper diagnosis in the fetus can also help optimize perinatal care in affected children. In three cases we illustrate that certain combinations of obstetric symptoms such as polyhydramnios, diminished fetal movements, malpresentation and abnormal fetal heart rhythm can help alert clinicians to the possibility of this syndrome in fetuses.


Asunto(s)
Síndrome de Prader-Willi/diagnóstico , Diagnóstico Prenatal/métodos , Adulto , Arritmias Cardíacas/etiología , Femenino , Movimiento Fetal/fisiología , Frecuencia Cardíaca Fetal/fisiología , Humanos , Presentación en Trabajo de Parto , Polihidramnios/etiología , Síndrome de Prader-Willi/diagnóstico por imagen , Embarazo , Ultrasonografía
19.
Int J Oral Maxillofac Surg ; 31(3): 296-302, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12190137

RESUMEN

Liquid nitrogen cryotherapy has been advocated as an adjunct in the enucleation and curettage of locally aggressive lesions of the jaws. Simultaneous autogenous bone grafting has also been advocated to accelerate bone formation and reduce morbidity. There is, however, relatively little scientific basis for either of these hypotheses. In this study, nine Yucatan minipigs had artificial defects created in the mandible, which were treated with liquid nitrogen spray. Half of the defects were grafted with autogenous bone from the chin and half were closed primarily. Two animals were sacrificed 3 days postoperatively to measure the width of necrosis and the rest were sacrificed at 3 months to assess healing and new bone formation. It was found that drilling the artificial defects alone caused bone necrosis for a mean depth of 0.09 mm. Liquid nitrogen cryospray caused a mean depth of bone necrosis of 0.82 mm (range 0.51-1.52 mm). The defects that were bone grafted healed well clinically. Defects not bone grafted showed a 50% rate of wound breakdown and sequestrum formation with delayed healing. Vital staining showed a non-significantly greater rate of bone formation in the grafted defects. Digitally superimposed radiography showed a non-significantly greater bone density in the non-grafted defects at 3 months postoperatively. It appears that liquid nitrogen cryospray does devitalize an area of bone around defects in the mandible. The width of necrosis is usually less than 1 mm and subsequent healing is enhanced by autogenous bone grafting. This has clinical implications.


Asunto(s)
Regeneración Ósea , Trasplante Óseo , Criocirugía/métodos , Mandíbula/cirugía , Procedimientos Quirúrgicos Orales/métodos , Animales , Mandíbula/diagnóstico por imagen , Modelos Animales , Nitrógeno , Osteonecrosis , Radiografía , Técnica de Sustracción , Porcinos , Porcinos Enanos
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 18(3): 419-21, 2001 Sep.
Artículo en Chino | MEDLINE | ID: mdl-11605505

RESUMEN

This study was aimed to evaluate a modified method for animal osteoblast marrow culture on the basis of previously published method. The marrow mononuclear cells(MMNC) in femoral bone-marrow of SD rat were gained with Ficoll-Hapaque centrifuge, which were then cultured in 5 x 10(5) cells/cm3 on the 96-well culture plates with RPMI 1640 medium containing 30% horse serum in a humidified atmosphere of 5% carbon dioxide at 37 degree Celsius. The medium was changed every three days. Cultured cells were identified with inverted microscopy for observing the shape of living cells, and with Wright-Geimsa mixture stain and Alkaline phosphatase (ALP) stain. In order to avoid false positive reaction, we caused damage to the ALP in cultured cells and stained the cells with ALP again for comparison. The results of inverted microscopy showed that the small spherical mononuclear cells became polygonal, spindle-shaped or squamous successively from the fifth day onward. Wright-Geimsa staining showed the specific property of osteoblast. ALP stain positive reaction was between "2+" and "3+", then ALP stain negative reaction was noticed after the damage to ALP. These data demonstrated that MMNC in SD rat could become osteoblast in RPMI 1640 medium containing 30% horse serum. The modified osteoblast marrow culture method has the advantages of short time, less risk of contamination and higher efficiency.


Asunto(s)
Células de la Médula Ósea , Técnicas de Cultivo de Célula/métodos , Osteoblastos/citología , Animales , Ratas , Ratas Sprague-Dawley
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