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1.
Sovrem Tekhnologii Med ; 12(5): 71-75, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796007

RESUMO

The main requirements for a screening test are simplicity, non-invasiveness, safety of testing procedures, high processing speed, and ability to detect diseases at an early stage. A multichannel gas analyzer for assessment of exhaled air composition (diode laser spectrometer), non-invasive screening, and biomedical testing was developed on the basis of near-infrared diode lasers with fiber output. The device measures the following exhaled air components: 12CO2, 13CO2, CH4, NH3, H2O, and H2S. The concentration of molecules was measured in a multi-pass Herriot cell with a reference length of 40 cm, 1.8 L volume, and a total optical path length of 26 m. Three diode lasers manufactured by NTT Electronics (Japan) were used in the work. Detection of CH4 was carried out in the 1.65 µm wavelength range, 12CO2, 13CO2, and H2S levels were measured in the 1.60 µm range, NH3 and H2O in the 1.51 µm range. All measurements were taken in real time. Clinical testing of the spectrometer was carried out at V.M. Buyanov City Clinical Hospital of Moscow Department of Health. More than 150 patients were examined. The tests included analysis and measurement of these molecular components in the exhaled air of patients with various diseases. The content of these components was studied in conditions of various changes in the human physiological state (dosed physical activity, relaxation, psychoemotional stress, etc.). The studies have demonstrated efficacy of using the developed hardware system for assessment of exhaled air components in order to reveal functional disorders in various diseases of the digestive system, cardiorespiratory system, diseases caused by impaired nitrogen-excreting function of the kidneys, etc.


Assuntos
Expiração , Lasers Semicondutores , Humanos , Japão , Moscou
2.
Sud Med Ekspert ; 64(1): 38-43, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33511833

RESUMO

Forensic examination of a gunshot injury is the most difficult problem of domestic and foreign forensic medicine. A large amount of knowledge and practical observations on damage from standard samples of handguns has been accumulated. The emergence of new unique samples of special-purpose weapons requires forensic physicians and forensic experts to conduct a complex of morphological, spectral, forensic chemical, medico-forensic, radiological and other special laboratory studies of damage caused by such weapons. The article presents a case of forensic medical examination commission with the issue solution of differential diagnosis of causing a mortal fire wound injuries by a specific sample of special-purpose handgun.


Assuntos
Armas de Fogo , Ferimentos por Arma de Fogo , Diagnóstico Diferencial , Balística Forense , Medicina Legal , Humanos , Radiografia , Ferimentos por Arma de Fogo/diagnóstico
3.
J Environ Sci Health B ; 53(11): 761-769, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30024815

RESUMO

The degradation dynamics and terminal residues of dufulin enantiomers were investigated in two typical corn plants. A convenient and precise chiral method by high-performance liquid chromatography coupled with tandem triple quadrupole mass spectrometry (HPLC/MS/MS) using a Chiralpak IC column was developed and validated for measuring dufulin enantiomers in corn plants and corn. The two enantiomers of dufulin quickly dissipated in the corn plant, and no noticeable stereoselectivity was observed during degradation or in the final residues. After 30% rac-dufulin wettable powder with a 1- to 1.5-fold dose of the recommended value was sprayed two to three times on corn plants, the residue levels of S-(+)-dufulin and R-(-)-dufulin in corn from both sites were lower than or equal to 0.0520 mg kg-1 on days 7, 14 and 21 after the last application. The dietary risk assessment indicated that dufulin did not exhibit obvious dietary health risks in corn samples when good agricultural practices were implemented. The findings from this study may be used to better understand the chiral profiles of dufulin in the environment and the effect of dufulin residues in corn on health.


Assuntos
Benzotiazóis/química , Benzotiazóis/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Zea mays/efeitos dos fármacos , Biodegradação Ambiental , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco , Estereoisomerismo , Zea mays/metabolismo
4.
Med Parazitol (Mosk) ; (2): 41-4, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27405216

RESUMO

Within the framework of the Federal External Quality Assessment (EQA) System and in the context of postgraduate training improvement for health workers in 2010-2014, specialists from the laboratories of the therapeutic-prophylactic organizations and institutions of the Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare were examined for their professional competence in microscopically identifying the pathogens of parasitic diseases in feces. The virtual remote educational computer technology tools that included different combinations of 16 helminthic species, 5 intestinal protozoan species, and a number of artefacts, were used. The specialists from 984 laboratories of multidisciplinary therapeutic-prophylactic organizations and hygiene and epidemiology centers in all Federal Districts of the Russian Federation were covered. A total of 8245 replies were analyzed. The detection rate for helminths was 64.0%, including those by a taxonomic group (nematodes, 65.0%; cestodes, 72.0%; trematodes, 55.1%). There was a dynamic decrease in the above indicators. There were low detection rates for trematodes parasitizing the small intestine (Metagonimus, 10.2%; Nanophyetus, 26.2%) and hepatobiliary organs (Fasciola, 59.6%; Clonorchis, 34.9%). The similar trend was seen in the detection rates for the pathogens of geohelminthisms (ascariasis, trichocephaliasis, etc.) and contagious helminthisms (enterobiasis, hymenolepiasis). The level of competence in detecting and identifying intestinal protozoa was much lower than the similar rates for helminthism pathogens. EQA for the laboratory diagnosis of the pathogens of parasitic diseases, by using the virtual tools is a leading element of the postgraduate training system for laboratory specialists. The results of EQA for the laboratory diagnosis of the pathogens of parasitic diseases are a basic material for the development, and improvement of training modernization programs, by applying a modular approach.


Assuntos
Cestoides/anatomia & histologia , Educação Médica Continuada , Ensaio de Proficiência Laboratorial/estatística & dados numéricos , Nematoides/anatomia & histologia , Trematódeos/anatomia & histologia , Animais , Cestoides/isolamento & purificação , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/parasitologia , Fezes/parasitologia , Humanos , Microscopia , Técnicas de Diagnóstico Molecular , Nematoides/isolamento & purificação , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas , Federação Russa , Trematódeos/isolamento & purificação , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/parasitologia , Recursos Humanos
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(5): 718-21, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27188370

RESUMO

OBJECTIVE: To discuss the suitability of frailty index for comprehensive geriatric assessment(FI-CGA)in the elderly in China, and evaluate the application of FI-CGA in China. METHODS: A comprehensive geriatric assessment was conducted among 118 old adults receiving health examination, and frailty index was calculated. Clinical frailty scale(CFS)was also used to evaluate the frail status of the old adults. The correlation between FI-CGA value and CFS level of the old adults was analyzed. RESULTS: The mean value of FI-CGA was 0.19 ± 0.07, and the average level of CFS was 3.11 ± 1.46. Women had higher mean value of FI-CGA and higher CFS level than men(FI-CGA= 0.20 ± 0.02 for women, 0.19 ± 0.07 for men; CFS =3.40 ± 0.55 for women, 3.10 ± 1.48 for men), but the differences had no significance(t=0.270, 0.452, P=0.788, 0.652). The FI-CGA value and CFS level increased with age(F=10.437, 5.651, P=0.000, 0.001); and there was a positive correlation between FI-CGA value and CFS level(r=0.615, P=0.000). CONCLUSION: FI-CGA is an effective model for the quantitative evaluation of the frail status of the elderly, and can be used in the clinical practice of geriatric medicine.


Assuntos
Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/métodos , Idoso , China , Avaliação da Deficiência , Feminino , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Valor Preditivo dos Testes
6.
Ultraschall Med ; 37(1): 63-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25140495

RESUMO

PURPOSE: Ultrasound is a well-established imaging modality in the assessment of malignant cervical lymphadenopathy. With the use of Doppler ultrasound, intranodal vascularity can be evaluated. However, the major limitation of ultrasound is operator dependency. Therefore, this study aimed to evaluate and compare the diagnostic accuracy and reliability of the subjective grading and computer-aided approach in assessing intranodal vascularity for the differentiation of benign and malignant lymph nodes. MATERIALS AND METHODS: The present study retrospectively assessed 99 power Doppler ultrasound images of cervical lymph nodes and evaluated the degree of intranodal vascularity using qualitative subjective grading (QSG) and quantitative computer-aided (QCA) methods. The diagnostic accuracy of the two methods in distinguishing metastatic and reactive nodes and their inter- and intra-rater reliability in assessing intranodal vascularity were evaluated and compared. RESULTS: The results showed that the QCA method was more accurate than the QSG method with a significantly higher sensitivity (67.8 % and 61.9 %, respectively, p < 0.05) and specificity (73.3 % and 57.3 %, respectively, p < 0.05). Using the intranodal vascularity index as determined by the QCA approach, the optimum cut-off to differentiate metastatic and reactive cervical lymph nodes was 32 %. The QCA method showed higher inter- and intra-rater reliability than the QSG method. CONCLUSION: In the assessment of the degree of intranodal vascularity, the QCA method was more accurate and reliable than the QSG method in distinguishing metastatic and reactive lymph nodes.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Linfonodos/irrigação sanguínea , Linfadenopatia/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Gradação de Tumores , Neoplasias Otorrinolaringológicas/irrigação sanguínea , Neoplasias Otorrinolaringológicas/diagnóstico por imagem , Ultrassonografia Doppler , Biópsia por Agulha Fina , Velocidade do Fluxo Sanguíneo , Competência Clínica , Diagnóstico Diferencial , Linfonodos/patologia , Metástase Linfática/patologia , Pescoço/diagnóstico por imagem , Variações Dependentes do Observador , Neoplasias Otorrinolaringológicas/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Tsitologiia ; 58(7): 548-54, 2016.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30198669

RESUMO

It is generally accepted that nuclear erythrocytes of some vertebrates are shaped like ellipses. Nevertheless, the formal proof for this has not been presented. Here, the experimental data and theoretical calculations are presented to prove that the shape of nuclear erythrocytes, as a mathematical expectation, is really the ellipse. In addition, allowable limits of deviation of the erythrocytes shape from the ellipse were shown. On the basis of the presented data we have introduced a new parameter (named «ellipsoid coefficient¼) to evaluate how the real cell shape fits to the correct ellipse. The coefficient is the ratio of the real erythrocyte area (A) to the calculated area (S) obtained by a direct measurement of the erythrocyte major (M) and minor (m) axes. We assume that this parameter can be used in taxonomy of the vertebrate animals having nuclear erythrocytes.


Assuntos
Núcleo Celular , Forma Celular , Eritrócitos/citologia , Animais , Peixes , Ranidae
8.
Lik Sprava ; (9-10): 108-13, 2014.
Artigo em Ucraniano | MEDLINE | ID: mdl-26492785

RESUMO

The article analyzes the dynamics of postoperative pain at single-port transumbilical laparoscopic cholecystectomy compared to traditional laparoscopic cholecystectomy. It is shown that the intensity of pain in patients who have undergone laparoscopic procedures through a single transumbilical access was significantly less than in patients with traditional laparoscopic intervention. Furthermore, the use of a single-port transumbilical laparoscopic cholecystectomy accompanied by a smaller increase in the concentration of proinflammatory cytokines compared with patients who had laparoscopic procedures through four trocar accesses.


Assuntos
Colecistectomia Laparoscópica/métodos , Dor Pós-Operatória/diagnóstico , Umbigo , Colecistectomia Laparoscópica/efeitos adversos , Humanos , Interleucina-1/sangue , Interleucina-6/sangue , Limiar da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/imunologia , Síndrome , Fator de Necrose Tumoral alfa/sangue , Umbigo/cirurgia
9.
Tob Control ; 17(3): 183-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18522971

RESUMO

OBJECTIVE: This study assesses the effects of a 2005 increase in funding for smoking cessation services on provider participation, patient utilisation of smoking cessation services and cessation outcome at a six-month follow-up. METHODS: Analyses are based on existing databases and on a follow-up study among smokers participating in the smoking cessation service. The effect of the policy is evaluated by comparing year 2004 (old policy) with year 2005 (new policy). The generalised estimating equations (GEE) method was conducted to examine the effects of increasing funding for smoking cessation services on monthly smoking cessation services provided per physician and yearly consultations received per patient. Logistic regression was used to examine the effects of increasing funding on smoking cessation outcome. RESULTS: The study found the increased reimbursement rates and medication subsidies for smoking cessation to be positively related to the number of physicians enrolling in the programme (1841 in 2004 vs 3466 in 2005), the number of cessation consultations per month per physician (5.1 vs 14.6) and the number of cessation visits per year per patient (2.0 vs 2.5). Male providers and providers belonging to the private sector were found to offer more cessation consultations. The number of subjects receiving this counselling increased from 22 167 in 2004 to 109 508 in 2005. After adjusting for consumer and provider factors the likelihood of successful quitting among those counselled did not change. Overall, smokers who were older, had attempted to quit in the past year, had lower nicotine dependence, had gone to more smoking cessation service visits, had received consultations in the public sector and were seen by physicians delivering fewer consultations were more likely to have quit smoking at the six-month follow-up. CONCLUSIONS: Based on increases in physician enrollment and consultations and the increase in number of subjects receiving counselling and number of visits, the policy of increasing provider incentives and medication subsidies appears to have successfully promoted smoking cessation services.


Assuntos
Assistência Ambulatorial/economia , Padrões de Prática Médica/economia , Abandono do Hábito de Fumar/economia , Adolescente , Adulto , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta/estatística & dados numéricos , Reembolso de Incentivo/economia , Taiwan
10.
Comput Methods Programs Biomed ; 85(1): 59-68, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17064809

RESUMO

A 3D numerical model was developed to study the flow field and oxygen transport in a micro-bioreactor with a rotating magnetic bar on the bottom to mix the culture medium. The Reynolds number (Re) was kept in the range of 100-716 to ensure laminar environment for animal cell culture. The volumetric oxygen transfer coefficient (k(L)a) was determined from the oxygen concentration distribution. It was found that the effect of the cell consumption on k(L)a could be negligible. A correlation was proposed to predict the liquid-phase oxygen transfer coefficient (k(Lm)) as a function of Re. The overall oxygen transfer coefficient (k(L)) was obtained by the two-resistance model. Another correlation, within an error of 15%, was proposed to estimate the minimum oxygen concentration to avoid cell hypoxia. By combination of the correlations, the maximum cell density, which the present micro-bioreactor could support, was predicted to be in the order of 10(12) cells m(-3). The results are comparable with typical values reported for animal cell growth in mechanically stirred bioreactors.


Assuntos
Reatores Biológicos , Custos e Análise de Custo , Oxigênio/metabolismo , Animais , Reatores Biológicos/economia , Células Cultivadas
11.
Bull Exp Biol Med ; 139(6): 678-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16224579

RESUMO

Conduction anesthesia of the vagus nerve produced by procaine (0.5%), marcaine (0.25%), richlocaine (0.5%), and imidazobenzoimidazole derivative RU-353 (0.25%) was compared in acute experiments on cats. RU-353 produced the most long-term local anesthesia (assessed by inhibition of cardiochronotropic effect of vagus nerve).


Assuntos
Anestesia por Condução , Anestésicos Locais/farmacologia , Benzimidazóis/farmacologia , Bupivacaína/farmacologia , Piperidinas/farmacologia , Procaína/farmacologia , Animais , Gatos , Avaliação Pré-Clínica de Medicamentos , Nervo Vago/efeitos dos fármacos
12.
J Trauma ; 51(6): 1122-6; discussion 1126-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11740264

RESUMO

BACKGROUND: This study assesses the relationship that the brand of trauma program registry (TPR) has on mortality rate (MR) in the reports prepared by the American College of Surgeons Committee on Trauma (ACSCOT) trauma center (TC) site surveyors. METHODS: Data from 242 ACSCOT adult TC survey reports (88 Level I, 115 Level II, and 39 Level III) were analyzed for annual trauma volume, injury severity score (ISS), MR, and TPR. Six TPR (A through F) were identified; group F was a composite of several infrequently used TPRs. This report focuses on the ISS range 16-24 because of the likelihood that the mean for each TC would be near 20 and MR is high enough so that a difference, if present, could be statistically documented. RESULTS: For the total group, MR showed no correlation with TC volume or TC level for ISS 16-24. MR was significantly different according to which TPR was used by the TCs. The MR is less (4.8%) for 14 high volume TCs (over 1200 admits) using TPR A compared with 33 low volume TCs (below 800 admits) using TPR A (6.34%). CONCLUSION: The MR for ISS 16-24 in ACSCOT-surveyed TCs differs within subgroups based on type of TPR utilized. This may reflect improper use of the software programs. Enhanced skill in the application of software programs designed to generate ISS scores is essential if meaningful studies on the effects of improved trauma care on MR are to be conducted. Hand scored ISS by trained personnel may circumvent this problem.


Assuntos
Grupos Diagnósticos Relacionados/estatística & dados numéricos , Sistema de Registros , Centros de Traumatologia/organização & administração , Ferimentos e Lesões/mortalidade , Fatores de Confusão Epidemiológicos , Interpretação Estatística de Dados , Humanos , Escala de Gravidade do Ferimento , Estados Unidos/epidemiologia , Ferimentos e Lesões/classificação
13.
J Craniofac Surg ; 12(4): 401-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11482629

RESUMO

Circular parietal defects from 3 to 12 mm in diameter were made in 45 6-month old skeletally mature guinea pigs, and animals were sacrificed after survival periods of 3 days to 12 weeks. The original defect was harvested in continuity with a rim of surrounding bone and the adjacent dura and pericranium. After 12 weeks, all 3 and 5 mm defects were completely covered by a bridge of bone, while residual defects were noted within the 8 and 12 mm wounds. Percentage of new bone formation was significantly higher within 3 mm defects, than in all larger defects at each time interval from 1 week on (P < .05), reaching a mean of 93% in 3 mm defects and remaining below a mean of 31% in the remaining defect sizes. Immunolocalization demonstrated an osteogenic front in which the osteoblasts stained strongly for all isoforms of TGF-beta, with the intensity decreasing after the majority of the defects had reossified; this front was located at the advancing bone edge of the defect as well as the endocranial side adjacent to the dura. In conclusion, isoforms of TGF-beta are upregulated during a limited "window" of time corresponding to the period of calvarial reossification, and are localized to osteoblasts within an osteogenic front at the periphery and dural surfaces of the defects.


Assuntos
Regeneração Óssea/fisiologia , Crânio/lesões , Fator de Crescimento Transformador beta/fisiologia , Cicatrização/fisiologia , Animais , Expressão Gênica , Cobaias , Imuno-Histoquímica , Masculino , Isoformas de Proteínas , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/química , Fator de Crescimento Transformador beta/genética , Regulação para Cima
14.
Pharmacol Res ; 42(2): 107-14, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10887038

RESUMO

Alzheimer's disease (AD), characterized by neuritic plaques and neurofibrillary tangles of the brain, is experienced by more and more elderly people in a form of senile dementia. Four genes are closely linked with AD and are located on chromosomes 21, 19, 14 and 1. Transgenic technology enables the development of animal models for research into this human disease. Recently reported transgenic AD mouse models, which express AD-related mutant human genes, develop some significant aspects of AD-like pathology. The specific role of these mice in representing different targets, the consequent pathology of AD and the availability of this increasingly popular tool for investigating new therapeutic strategies for AD are reviewed.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/etiologia , Modelos Animais de Doenças , Doença de Alzheimer/patologia , Animais , Humanos , Camundongos , Camundongos Transgênicos
15.
Int J Radiat Oncol Biol Phys ; 46(4): 1071-5, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10705032

RESUMO

PURPOSE: To investigate the accuracy of in vivo dosimetry using radiochromic film for large single-fraction, low-energy irradiations. METHODS AND MATERIALS: Gafchromic MD-55-2 radiochromic film and LiF thermoluminescent dosimeters (TLDs) were placed in vivo on 25 patients to ascertain their effectiveness for assessment of dose. All patients received 10 Gy single fractions at energies ranging from 100 kVp (half-value layer [HVL] = 3.5 mm Al) up to 250 kVp (HVL = 2.3 mm Cu). Effects of small air gaps were also investigated using LiF TLDs and radiochromic film. RESULTS: Radiochromic film adequately measured applied dose for 25 patients in vivo with a standard deviation of 5.5% from prescribed dose. LiF TLDs recorded a standard deviation of 4.1% from measured to applied dose. Small air gaps which can be created under the film or TLDs during in vivo dosimetry were shown to have a measurable but minimal effect on results for gaps less than 5 mm. CONCLUSIONS: Gafchromic film has adequately measured applied dose in vivo at low energy for large 10 Gy single-fraction irradiation.


Assuntos
Dosagem Radioterapêutica , Filme para Raios X , Fluoretos , Humanos , Compostos de Lítio , Fenômenos Físicos , Física , Radiometria/instrumentação , Radiometria/métodos
16.
Rev Laryngol Otol Rhinol (Bord) ; 121(5): 301-5, 2000.
Artigo em Francês | MEDLINE | ID: mdl-11387653

RESUMO

Measurement of the vibration instability by means of jitter in cases of dysphonia fails to take into account certain features of the vocal signal, such as modulation or bitonatily. These abnormalities appear in jitter measurements as instability, without allowing any differentiation from random instability (to give 'true' instability). The authors suggest the use of the coefficient of Lyapunov, a measurement which is used for nonlinear dynamics. The vocal product of 179 normal and dysphonic subjects has been analysed. The coefficient of Lyapunov and the jitter were measured during the stable period of a sustained 'a' vowel. For the coefficient of Lyapunov, the authors used the algorythm which has been published previously [Giovanni et al, J. Voice 1999;13:341-354]. The measurements were compared with the perceptive analysis of the reading voice by a panel, and divided into four grade (G0 to G3). The coefficient of Lyapunov appeared to be more relevant than the jitter in distinguishing the various perceived grades. Precise recognition of the grade was obtained in 46% using the coefficient of Lyapunov as against only 36% using jitter. The addition of this new index to the existing puriparametric methods of voice analysis seems to be promising.


Assuntos
Distúrbios da Voz/diagnóstico , Voz/fisiologia , Acústica , Algoritmos , Interpretação Estatística de Dados , Análise Discriminante , Feminino , Humanos , Modelos Lineares , Masculino , Dinâmica não Linear , Vibração , Distúrbios da Voz/fisiopatologia
17.
Anal Biochem ; 270(1): 97-102, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10328770

RESUMO

Methylglyoxal, a toxic aldehyde, has been reported to be increased in diabetes and has been claimed to be related to diabetic complications. Aminoacetone, an intermediate in the metabolism of threonine and glycine, has been proposed to be an endogenous substrate for semicarbazide-sensitive amine oxidase (SSAO). Methylglyoxal is the product. An HPLC procedure for the determination of SSAO activity toward aminoacetone in vitro is described. It was observed in previous assays that methylglyoxal formed via deamination of aminoacetone was quite unstable and led to erroneous results. o-Phenylenediamine (o-PD) was therefore employed for derivatization of methylglyoxal. o-PD does not affect SSAO activity and can be included in the enzyme reaction mixture for continuous trapping of methylglyoxal. This can avoid the loss of methylglyoxal during incubation. Deamination of aminoacetone by human umbilical artery SSAO was confirmed with this improved assay. The values of Km and Vmax, are 125.9 +/- 20.5 microM and 332.2 +/- 11.7 nmol/h/mg protein, respectively. Deamination of aminoacetone was nearly completely inhibited by 1 mM semicarbazide and 1 microM MDL-72974A, a potent selective SSAO inhibitor, whereas MAO inhibitors clorgyline (1 mM) and deprenyl (1 mM) had no inhibitory effect.


Assuntos
Acetona/análogos & derivados , Amina Oxidase (contendo Cobre)/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Fenilenodiaminas , Aldeído Pirúvico/análise , Semicarbazidas/farmacologia , Acetona/metabolismo , Compostos Alílicos/farmacologia , Benzilaminas/metabolismo , Butilaminas/farmacologia , Catálise , Clorgilina/farmacologia , Desaminação , Inibidores Enzimáticos/farmacologia , Humanos , Cinética , Inibidores da Monoaminoxidase/farmacologia , Selegilina/farmacologia , Artérias Umbilicais/enzimologia
20.
Appl Radiat Isot ; 48(7): 985-90, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9376828

RESUMO

The steep dose gradient around 192Ir brachytherapy wire implants is predicted by the EGS4 (PRESTA version) Monte Carlo simulation. When considering radiation absorbing regions close to the wire source, the accurate dose distribution cannot be calculated by the GE Target II Sun Sparc treatment-planning system. Experiments using GafChromic film have been performed to prove the validity of the EGS4 user code when calculating the dose close to the wire source in a low energy range.


Assuntos
Braquiterapia/instrumentação , Radioisótopos de Irídio , Planejamento da Radioterapia Assistida por Computador , Braquiterapia/métodos , Simulação por Computador , Método de Monte Carlo , Imagens de Fantasmas , Dosagem Radioterapêutica , Filme para Raios X
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