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1.
Transfus Clin Biol ; 30(2): 272-278, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36898574

RESUMO

OBJECTIVES: To date, no study has been done yet on the distribution of Hepatitis C virus genotypes in Lubumbashi, Democratic Republic of Congo. The objective of this work was to determine the seroprevalence and study the distribution of hepatitis C virus (HCV) genotypes among blood donors in Lubumbashi, DRC. METHODS: This was a cross-sectional descriptive study among blood donors. The detection of anti-HCV antibodies was carried out by rapid diagnostic test (RDT) then confirmed by Chemiluminescent immuno-assay (CLIA). Viral load was determined by Nucleic Acid Amplification test (NAT) on Panther system and genotyping by Next Generation Sequencing (NGS) on Sentosa platform. RESULTS: The obtained seroprevalence was 4.8%. Genotypes 3a (5.0%), 4 (90.0%) and 7 (5.0%) and a few drug resistance mutations were identified in the study population. Significant disturbances of some studied biochemical parameters (HDL-cholesterol, direct bilirubin, transaminases, ALP, GGT and albumin) have been observed in positive HCV blood donors. Irregular family and volunteer donors have been found as the socio-demographic characteristics associated with hepatitis C. CONCLUSION: With a seroprevalence of 4.8% obtained among blood donors, Lubumbashi is in an area with medium endemicity for HCV, highlighting the need to implement strategies aiming to improve transfusion safety among blood recipients in Lubumbashi. This study reports for the first time the presence of HCV strains of genotypes 3a, 4 and 7. These results might allow better therapeutic management of HCV infections and contribute to the development of the mapping of HCV genotypes in Lubumbashi and DRC as well.


Assuntos
Hepacivirus , Hepatite C , Humanos , Hepacivirus/genética , Doadores de Sangue , Estudos Soroepidemiológicos , Estudos Transversais , República Democrática do Congo/epidemiologia , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C
2.
Clin Interv Aging ; 12: 1065-1077, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28740372

RESUMO

The incidence of osteoporotic fractures increases with age. Consequently, the global prevalence of osteoporotic fractures will increase with the aging of the population. In old age, osteoporosis is associated with a substantial burden in terms of morbidity and mortality. Nevertheless, osteoporosis in old age continues to be underdiagnosed and undertreated. This may, at least partly, be explained by the fact that evidence of the antifracture efficacy of osteoporosis treatments comes mainly from randomized controlled trials in postmenopausal women with a mean age of 70-75 years. However, in the last years, subgroup analyses of these landmark trials have been published investigating the efficacy and safety of osteoporosis treatment in the very elderly. Based on this evidence, this narrative review discusses the pharmacological management of osteoporosis in the oldest old (≥80 years). Because of the high prevalence of calcium and/or vitamin D deficiency in old age, these supplements are essential in the management of osteoporosis in the elderly people. Adding antiresorptive or anabolic treatments or combinations, thereof, reduces the risk of vertebral fractures even more, at least in the elderly with documented osteoporosis. The reduction of hip fracture risk by antiresorptive treatments is less convincing, which may be explained by insufficient statistical power in some subanalyses and/or a higher impact of nonskeletal risk factors in the occurrence of hip fractures. Compared with younger individuals, a larger absolute risk reduction is observed in the elderly because of the higher baseline fracture risk. Therefore, the elderly will benefit more of treatment. In addition, current osteoporosis therapies also appear to be safe in the elderly. Although more research is required to further clarify the effect of osteoporosis drugs in the elderly, especially with respect to hip fractures, there is currently sufficient evidence to initiate appropriate treatment in the elderly with osteoporosis and osteoporotic fractures.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Cálcio/deficiência , Cálcio da Dieta , Suplementos Nutricionais , Difosfonatos/uso terapêutico , Feminino , Fraturas do Quadril/prevenção & controle , Humanos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fatores de Risco , Fraturas da Coluna Vertebral/prevenção & controle , Deficiência de Vitamina D/epidemiologia
3.
Calcif Tissue Int ; 101(2): 111-131, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28324124

RESUMO

In this consensus paper, the Belgian Bone Club aims to provide a state of the art on the epidemiology, diagnosis, and management of osteoporosis in frail individuals, including patients with anorexia nervosa, patients on dialysis, cancer patients, persons with sarcopenia, and the oldest old. All these conditions may indeed induce bone loss that is superimposed on physiological bone loss and often remains under-recognized and under-treated. This is of particular concern because of the major burden of osteoporotic fractures in terms of morbidity, mortality, and economic cost. Therefore, there is an urgent need to appreciate bone loss associated with these conditions, as this may improve diagnosis and management of bone loss and fracture risk in clinical practice.


Assuntos
Consenso , Fraturas Ósseas , Osteoporose , Sarcopenia/complicações , Idoso , Animais , Bélgica , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/terapia , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/terapia , Idoso Fragilizado , Humanos , Osteoporose/complicações , Osteoporose/diagnóstico , Osteoporose/terapia , Sarcopenia/diagnóstico , Sarcopenia/terapia
4.
J Hazard Mater ; 314: 88-94, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27107238

RESUMO

The total oxidation of trichloroethylene (TCE) in air at low relative humidity (RH=10%) in the presence of CO2 (520ppmv) was investigated in function of energy density using an atmospheric pressure negative DC luminescent glow discharge combined with a cryptomelane catalyst positioned downstream of the plasma reactor at a temperature of 150°C. When using Non-Thermal Plasma (NTP) alone, it is found a low COx (x=1-2) yield in agreement with the detection of gaseous polychlorinated by-products in the outlet stream as well as ozone which is an harmful pollutant. Introduction of cryptomelane enhanced trichloroethylene removal, totally inhibited plasma ozone formation and increased significantly the COx yield. The improved performances of the hybrid system were mainly ascribed to the total destruction of plasma generated ozone on cryptomelane surface to produce active oxygen species. Consequently these active oxygen species greatly enhanced the abatement of the plasma non-reacted TCE and completely destroyed the hazardous plasma generated polychlorinated intermediates. The facile redox of Mn species associated with oxygen vacancies and mobility as well as the textural properties of the catalyst might also contribute as a whole to the efficiency of the process.

5.
Cereb Cortex ; 26(4): 1401-1408, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25323417

RESUMO

To create subjective experience, our brain must translate physical stimulus input by incorporating prior knowledge and expectations. For example, we perceive color and not wavelength information, and this in part depends on our past experience with colored objects ( Hansen et al. 2006; Mitterer and de Ruiter 2008). Here, we investigated the influence of object knowledge on the neural substrates underlying subjective color vision. In a functional magnetic resonance imaging experiment, human subjects viewed a color that lay midway between red and green (ambiguous with respect to its distance from red and green) presented on either typical red (e.g., tomato), typical green (e.g., clover), or semantically meaningless (nonsense) objects. Using decoding techniques, we could predict whether subjects viewed the ambiguous color on typical red or typical green objects based on the neural response of veridical red and green. This shift of neural response for the ambiguous color did not occur for nonsense objects. The modulation of neural responses was observed in visual areas (V3, V4, VO1, lateral occipital complex) involved in color and object processing, as well as frontal areas. This demonstrates that object memory influences wavelength information relatively early in the human visual system to produce subjective color vision.


Assuntos
Percepção de Cores/fisiologia , Reconhecimento Psicológico/fisiologia , Córtex Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Adulto Jovem
6.
Rev Med Brux ; 37(3): 145-151, 2016.
Artigo em Francês | MEDLINE | ID: mdl-28525187

RESUMO

Delirium (acute confusion) is a common, morbid, and costly geriatric syndrome that affects onethird of hospitalized older adults. As evidence mounts that delirium may persist for weeks to months, concern about delirium can no longer be restricted to acute hospitals. We present a review about non-pharmacologic and pharmacologic management of delirium in institution.


Le " Delirium " (état confusionnel) est un syndrome gériatrique fréquent et coûteux qui affecte un tiers des personnes âgées hospitalisées ; sa prévalence en institution est mal connue. Il apparaît que ce syndrome peut persister pendant des semaines à des mois, et n'est donc pas limité aux hospitalisations aiguës. Nous présentons une revue de la littérature sur la prise en charge du delirium en institution suivie d'une proposition d'algorithme définissant l'approche pharmacologique et non pharmacologique de ce syndrome gériatrique.


Assuntos
Delírio/tratamento farmacológico , Psicotrópicos/uso terapêutico , Idoso , Envelhecimento , Humanos
7.
Med Phys ; 42(1): 305-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25563270

RESUMO

PURPOSE: Silicon photodetectors are of significant interest for use in positron emission tomography (PET) systems due to their compact size, insensitivity to magnetic fields, and high quantum efficiency. However, one of their main disadvantages is fluctuations in temperature cause strong shifts in gain of the devices. PET system designs with high photodetector density suffer both increased thermal density and constrained options for thermally regulating the devices. This paper proposes a method of thermally regulating densely packed silicon photodetectors in the context of a 1 mm(3) resolution, high-sensitivity PET camera dedicated to breast imaging. METHODS: The PET camera under construction consists of 2304 units, each containing two 8 × 8 arrays of 1 mm(3) LYSO crystals coupled to two position sensitive avalanche photodiodes (PSAPD). A subsection of the proposed camera with 512 PSAPDs has been constructed. The proposed thermal regulation design uses water-cooled heat sinks, thermoelectric elements, and thermistors to measure and regulate the temperature of the PSAPDs in a novel manner. Active cooling elements, placed at the edge of the detector stack due to limited access, are controlled based on collective leakage current and temperature measurements in order to keep all the PSAPDs at a consistent temperature. This thermal regulation design is characterized for the temperature profile across the camera and for the time required for cooling changes to propagate across the camera. These properties guide the implementation of a software-based, cascaded proportional-integral-derivative control loop that controls the current through the Peltier elements by monitoring thermistor temperature and leakage current. The stability of leakage current, temperature within the system using this control loop is tested over a period of 14 h. The energy resolution is then measured over a period of 8.66 h. Finally, the consistency of PSAPD gain between independent operations of the camera over 10 days is tested. RESULTS: The PET camera maintains a temperature of 18.00 ± 0.05 °C over the course of 12 h while the ambient temperature varied 0.61 °C, from 22.83 to 23.44 °C. The 511 keV photopeak energy resolution over a period of 8.66 h is measured to be 11.3% FWHM with a maximum photopeak fluctuation of 4 keV. Between measurements of PSAPD gain separated by at least 2 day, the maximum photopeak shift was 6 keV. CONCLUSIONS: The proposed thermal regulation scheme for tightly packed silicon photodetectors provides for stable operation of the constructed subsection of a PET camera over long durations of time. The energy resolution of the system is not degraded despite shifts in ambient temperature and photodetector heat generation. The thermal regulation scheme also provides a consistent operating environment between separate runs of the camera over different days. Inter-run consistency allows for reuse of system calibration parameters from study to study, reducing the time required to calibrate the system and hence to obtain a reconstructed image.


Assuntos
Tomografia por Emissão de Pósitrons/instrumentação , Temperatura , Desenho de Equipamento , Tomografia por Emissão de Pósitrons/métodos , Software
8.
Med Phys ; 37(11): 5838-49, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21158296

RESUMO

PURPOSE: This study aims to address design considerations of a high resolution, high sensitivity positron emission tomography scanner dedicated to breast imaging. METHODS: The methodology uses a detailed Monte Carlo model of the system structures to obtain a quantitative evaluation of several performance parameters. Special focus was given to the effect of dense mechanical structures designed to provide mechanical robustness and thermal regulation to the minuscule and temperature sensitive detectors. RESULTS: For the energies of interest around the photopeak (450-700 keV energy window), the simulation results predict a 6.5% reduction in the single photon detection efficiency and a 12.5% reduction in the coincidence photon detection efficiency in the case that the mechanical structures are interspersed between the detectors. However for lower energies, a substantial increase in the number of detected events (approximately 14% and 7% for singles at a 100-200 keV energy window and coincidences at a lower energy threshold of 100 keV, respectively) was observed with the presence of these structures due to backscatter. The number of photon events that involve multiple interactions in various crystal elements is also affected by the presence of the structures. For photon events involving multiple interactions among various crystal elements, the coincidence photon sensitivity is reduced by as much as 20% for a point source at the center of the field of view. There is no observable effect on the intrinsic and the reconstructed spatial resolution and spatial resolution uniformity. CONCLUSIONS: Mechanical structures can have a considerable effect on system sensitivity, especially for systems processing multi-interaction photon events. This effect, however, does not impact the spatial resolution. Various mechanical structure designs are currently under evaluation in order to achieve optimum trade-off between temperature stability, accurate detector positioning, and minimum influence on system performance.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Tomografia por Emissão de Pósitrons/métodos , Diagnóstico por Imagem/métodos , Desenho de Equipamento , Humanos , Método de Monte Carlo , Fótons , Reprodutibilidade dos Testes , Espalhamento de Radiação , Temperatura , Fatores de Tempo
9.
Phys Med Biol ; 55(19): 5895-911, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20844332

RESUMO

Performance of a new high resolution PET detection concept is presented. In this new concept, annihilation radiation enters the scintillator detectors edge-on. Each detector module comprises two 8 × 8 LYSO scintillator arrays of 0.91 × 0.91 × 1 mm(3) crystals coupled to two position-sensitive avalanche photodiodes (PSAPDs) mounted on a flex circuit. Appropriate crystal segmentation allows the recording of all three spatial coordinates of the interaction(s) simultaneously with submillimeter resolution. We report an average energy resolution of 14.6 ± 1.7% for 511 keV photons at FWHM. Coincident time resolution was determined to be 2.98 ± 0.13 ns FWHM on average. The coincidence point spread function (PSF) has an average FWHM of 0.837 ± 0.049 mm (using a 500 µm spherical source) and is uniform across the arrays. Both PSF and coincident time resolution degrade when Compton interactions are included in the data. Different blurring factors were evaluated theoretically, resulting in a calculated PSF of 0.793 mm, in good agreement with the measured value.


Assuntos
Tomografia por Emissão de Pósitrons/instrumentação , Contagem de Cintilação/instrumentação , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador , Fatores de Tempo
10.
Eur J Clin Nutr ; 57(2): 376-82, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12571674

RESUMO

OBJECTIVE: To determine the effect of high-protein diets, which have recently been promoted for their health benefits, on urinary calcium losses and bone turnover in older subjects. DESIGN: Randomized controlled cross-over study. SETTING: Teaching hospital and university. SUBJECTS: Twenty hyperlipidemic men and postmenopausal women (age 56+/-2 y) completed the study. INTERVENTION: One-month test and control phases during which subjects consumed equi-energy metabolic diets high in calcium (1578 and 1593 mg/day, respectively). On the test diet 11% of total dietary energy from starch in the control bread was replaced by protein (wheat gluten), resulting in 27% of energy from protein on the test diet vs 16% on the control diet. MAIN OUTCOME MEASURE: Urinary calcium excretion. RESULTS: Compared with the control diet, at week 4, the test diet increased mean (+/-s.e.m.) 24 h urinary output of calcium (139+/-15 vs 227+/-21 mg, P=0.004). The treatment difference in urinary calcium loss correlated with the serum anion gap as a marker of metabolic acid production (r=0.57, P=0.011). Serum calcium levels were marginally lower 2.41+/-0.02 vs 2.38+/-0.02 mmol/l (P=0.075), but there was no significant treatment difference in calcium balance, possibly related to the high background calcium intake on both diets. CONCLUSION: In the presence of high dietary calcium intakes the vegetable protein gluten does not appear to have a negative effect on calcium balance despite increased urinary calcium loss.


Assuntos
Cálcio/urina , Proteínas Alimentares/farmacologia , Verduras , Adulto , Idoso , Estudos Cross-Over , Dieta , Proteínas Alimentares/sangue , Proteínas Alimentares/urina , Fezes , Feminino , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/urina , Masculino , Pessoa de Meia-Idade , Pós-Menopausa/urina
12.
Clin Microbiol Infect ; 6(4): 213-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11168110

RESUMO

OBJECTIVE: In order to evaluate the interlaboratory variation of HIV-1 RNA measurements in plasma, the Belgian AIDS reference laboratories organized a blinded multicenter quality control study. METHODS: Atest panel of coded spiked HIV-1 plasma samples reflecting the dynamic range of the assay was composed and distributed. The HIV-1 RNA concentration of these samples was determined by the eight Belgian AIDS reference laboratories by means of the Amplicor HIV-1 Monitor version 1.5 assay. RESULTS: Analysis of the results demonstrated that there was little interlaboratory variation for the high concentration range (4.0-5.7 log10 copies/mL), never exceeding 0.2 log10 copies/mL. However the standard deviation for the low concentration range (2.6-3.9 log10 copies/mL) reached up to 0.22 log10 copies/mL. CONCLUSIONS: Since interlaboratory variability never reached 0.5 log10 copies/mL and each of the laboratories was able to detect four-fold differences in plasma HIV-1 RNA levels, the Amplicor assay can be used in multicenter studies without a centralized analysis of samples. Furthermore, this well-characterized proficiency panel of spiked plasma samples could be used as a standard in the study of interassay comparisons.


Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Laboratórios/normas , Reação em Cadeia da Polimerase/normas , RNA Viral/sangue , Bélgica , Infecções por HIV/sangue , HIV-1/genética , Humanos , Controle de Qualidade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
13.
Lancet ; 352(9142): 1739-41, 1998 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-9848349

RESUMO

BACKGROUND: The cause of fulminant hepatitis (FH) in children is unexplained in up to 50% of cases. We report parvovirus B19 as an agent associated with FH in children and compare clinical characteristics of these patients with those of age-matched patients with FH of other origin. METHODS: 45 patients presented with FH. No cause was apparent in 21 patients. Parvovirus B19 genome was retrospectively sought by PCR in serum collected at admission in 41 patients. FINDINGS: Parvovirus B19 genome was detected in serum from four of 21 patients with unexplained FH (four of 11 younger than 5 years). No B19 DNA was detected in serum from patients with other types of FH or from 82 patients with biliary atresia. Parvovirus B19 IgM was detected in one of the four patients. Patients with parvovirus B19 infection had significantly lower bilirubin concentrations than age-matched patients with FH due to hepatitis A (nine) or other causes (nine) (poisoning with amanita excluded). All patients with parvovirus B19 survived without orthotopic liver transplantation, with restoration of normal liver function within 17 days. INTERPRETATION: In patients younger than 5 years with FH of unexplained origin, evidence of acute parvovirus B19 was associated with a distinct clinical pattern. In particular, low bilirubin concentrations and rapid recovery of liver function without transplantation were distinctive features.


Assuntos
Encefalopatia Hepática/virologia , Hepatite Viral Humana/virologia , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano , Pré-Escolar , Genoma Viral , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/mortalidade , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/mortalidade , Humanos , Lactente , Testes de Função Hepática , Infecções por Parvoviridae/diagnóstico , Parvovirus B19 Humano/genética , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
14.
Arch Virol ; 143(6): 1077-92, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9687866

RESUMO

As previously reported, a C-type retrovirus, referred to as retrovirus X was isolated from HIV infected cells. In order to further characterize this virus, the proviral DNA was cloned and sequenced. The organization of the genome (8379 bp) appeared to be typical of the mammalian type C retroviruses. The virus was shown to be closely related to the gibbon ape leukaemia virus (GALV) with 87% similarity when the sequence was compared with the published genome of the Seato strain of GALV. At the level of the long terminal repeat where comparison was possible with other strains, the closest relationship was found with the San Francisco strain of GALV and with the simian sarcoma virus. These results suggest that the isolate should be considered as a strain of GALV.


Assuntos
DNA Viral/química , Gammaretrovirus/genética , Provírus/genética , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular , Clonagem Molecular , HIV/crescimento & desenvolvimento , Dados de Sequência Molecular , Fases de Leitura Aberta , Sequências Repetitivas de Ácido Nucleico
15.
Exp Aging Res ; 24(1): 3-19, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9459060

RESUMO

In 2 experiments, time-accuracy curves were derived for recall and recognition from episodic memory for both young and older adults. In Experiment 1, time-accuracy functions were estimated for free list recall and list recall cued by rhyme words or semantic associations for 13 young and 13 older participants. In Experiment 2, time-accuracy functions were estimated for recognition of word lists with or without distractor items and with or without articulatory suppression for 29 young and 30 older participants. In both studies, age differences were found in the asymptote (i.e., the maximum level of performance attainable) and in the rate of approach toward the asymptote (i.e., the steepness of the curve). These two parameters were only modestly correlated. In Experiment 2, it was found that 89% of the age-related variance in the rate of approach and 62% of the age-related variance in the asymptote was explained by perceptual speed. The data point at the existence of 2 distinct effects of aging on episodic memory, namely a dynamic effect (growing slower) and an asymptotic effect (growing less accurate). The absence of Age x Condition interactions in the age-related parameters in either experiment points at the rather general nature of both aging effects.


Assuntos
Envelhecimento/fisiologia , Memória/fisiologia , Rememoração Mental/fisiologia , Adulto , Humanos , Pessoa de Meia-Idade , Tempo de Reação , Análise e Desempenho de Tarefas , Fatores de Tempo
16.
J Clin Pathol ; 50(6): 481-4, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9378813

RESUMO

AIMS: To date, the risk relating to the handling or allografting of human immunodeficiency virus type 1 (HIV-1) infected postmortem skin remains hypothetical. While blood screening for HIV antibodies is still the key safety procedure to detect HIV infected cadavers, false negative results are a concern. Conversely, false positive results may hamper the collection of skin allografts. Accordingly, viral culture was used to clarify skin infectivity and the nested polymerase chain reaction (PCR) was used to assess the reliability of skin PCR testing. METHODS: Viral culture and nested PCR performed with gag and pol specific primers were investigated in cadaveric skin and blood from 12 HIV-1 infected patients. Samples were collected repeatedly between one and five days in seven patients. In most cases, analyses were performed on triplicate skin samples: fresh (n = 26); cryopreserved in 5% dimethylsulphoxide (n = 21), or cryopreserved in 30% glycerol (n = 26). RESULTS: HIV was isolated in two of 26 cultures of fresh skin specimens (8%), seven of 47 cryopreserved skin specimens (15%), and eight of 26 blood specimens (31%). The nested PCR detected HIV-1 in all skin samples (n = 73), regardless of the postmortem interval or cryopreservation. In blood, a positive signal was found in eight of 12 patients but two of them had discordant results on successive samples. CONCLUSIONS: These data suggest that nested PCR on postmortem skin samples can detect HIV more reliably than on blood. They also demonstrate the potential viral infectivity of fresh or stored skin postmortem samples in HIV infected patients. They underscore the need for caution during the handling of skin tissue from HIV infected cadavers and confirm the potential risk related to accidental allografting of HIV contaminated skin.


Assuntos
Síndrome da Imunodeficiência Adquirida/virologia , HIV-1/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Pele/virologia , Cadáver , Estudos de Casos e Controles , Criopreservação , Reações Falso-Negativas , Humanos , Transplante de Pele , Transplante Homólogo
17.
J Virol Methods ; 51(2-3): 305-16, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7738151

RESUMO

Eight Belgian AIDS Reference Laboratories established a multicentre quality control to evaluate the performance of their diagnostic human immunodeficiency virus type 1 (HIV-1) DNA polymerase chain reaction (PCR). A set of Belgian and African HIV-1 seropositive and seronegative patient samples, collected in Belgium, and the British Medical Research Council (MRC) HIV-1 PCR reference reagent kit, containing plasmid HIV-1 DNA at several dilutions in human carrier DNA with appropriate negative controls, were tested by the laboratories. No false positive results were reported. All laboratories were able to detect one to two copies of HIV-1 DNA. Among the 17 Belgian and African HIV-1 seropositives, some laboratories reported up to four indeterminate results, mainly due to failure of the SK38-39, SK68-69 (Ou et al. (1988) Science 239, 295-297) and/or gag881-882 (Simmonds et al. (1990) J. Virol. 64, 864-872) primers and a poorly performing algorithm. Only the H1POL4235-4538 nested pol primer set, developed by one of the laboratories, correctly identified all the tested HIV-1 positive and negative samples. Consequently, the laboratories decided to evaluate these pol primers as a reference primer set and to standardise the testing algorithm. All laboratories achieved a sensitivity and specificity of 100% on testing 10 additional Belgian and African patient samples, when adapting a standardised algorithm based on three HIV-1 primer sets, one of which is the H1POL4235-4538 primer set.


Assuntos
Algoritmos , Primers do DNA/normas , Infecções por HIV/diagnóstico , HIV-1 , Reação em Cadeia da Polimerase/normas , África , Sequência de Bases , Bélgica , DNA Viral/sangue , Estudos de Avaliação como Assunto , Genes pol/genética , HIV-1/genética , Humanos , Dados de Sequência Molecular , Controle de Qualidade , Sensibilidade e Especificidade
18.
Antimicrob Agents Chemother ; 39(1): 28-33, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7695325

RESUMO

Current dosage regimens of trimethoprim-sulfamethoxazole used to treat Pneumocystis carinii pneumonia in AIDS patients have been based on data from healthy subjects or patients without AIDS. The clearance and absorption characteristics of the drugs may potentially be different between patients with and without AIDS. This study was conducted to assess the pharmacokinetics of trimethoprim-sulfamethoxazole in critically ill and non-critically ill AIDS patients treated for P. carinii pneumonia. Patients received trimethoprim at 15 mg/kg of body weight and sulfamethoxazole at 75 mg/kg of body weight daily intravenously in three to four divided doses and were switched to the oral route when the regimen was tolerated. Serum samples for determination of drug concentrations were obtained over 12 h after intravenous and oral dosing. The pharmacokinetics of trimethoprim and sulfamethoxazole were compared in eight critically ill versus nine non-critically ill male patients and were as follows, respectively: clearance, 1.88 +/- 0.44 versus 1.73 +/- 0.64 ml/min/kg for trimethoprim and 0.40 +/- 0.12 versus 0.34 +/- 0.11 ml/min/kg for sulfamethoxazole; volume of distribution, 1.6 +/- 0.5 versus 1.5 +/- 0.5 liters/kg for trimethoprim and 0.5 +/- 0.3 versus 0.4 +/- 0.1 liters/kg for sulfamethoxazole; and half-life, 10.9 +/- 7.4 versus 11.3 +/- 4.0 h for trimethoprim, and 15.5 +/- 9.5 versus 14.3 +/- 4.7 h for sulfamethoxazole. No significant differences (P > 0.05) were observed between patient groups, although there was wide intersubject variability. Absorption appeared to be similar between the critically ill and non-critically patients: bioavailability was 97.5% +/- 22.4% versus 101.8% +/- 22.7% for trimethoprim and 86.2% +/- 17.9% versus 99.1% +/- 20.5% for sulfamethoxazole, respectively. Because of the similar pharmacokinetics of trimethoprim-sulfamethoxazole in critically ill and non-critically ill AIDS patients, the two groups of patients may receive similar dosages. Dosage adjustment does not appear to be required when switching from the intravenous to the oral route.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/metabolismo , Pneumonia por Pneumocystis/metabolismo , Combinação Trimetoprima e Sulfametoxazol/farmacocinética , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , APACHE , Administração Oral , Adulto , Disponibilidade Biológica , Estado Terminal , Meia-Vida , Humanos , Injeções Intravenosas , Masculino , Pneumonia por Pneumocystis/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Combinação Trimetoprima e Sulfametoxazol/sangue
19.
Mol Cell Endocrinol ; 97(1-2): 159-64, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8143899

RESUMO

The bombesin-related peptides gastrin-releasing peptide (GRP) and neuromedin B (NMB) have been demonstrated in the anterior pituitary (AP) on an immunological basis. We studied the presence of mRNAs for these peptides and for their receptors by RNAse protection assay using fresh adult male rat AP, AP cell reaggregates cultured in the presence of estradiol and the rat AP derived GH3 cell line. In total RNA from fresh AP we detected high amounts of NMB mRNA and much smaller amounts of GRP mRNA, while finding a weak signal for GRP-receptor (GRP-R) and NMB-receptor (NMB-R) mRNAs. In total RNA from the reaggregate cell cultures we detected high levels of NMB mRNA as well as a strong signal for GRP-R mRNA. Finally, in GH3 cells, high levels of NMB mRNA and GRP-R mRNA were found, while GRP mRNA and NMB-R mRNA remained undetectable even in high amounts (200 micrograms) of total RNA. We conclude that mRNAs encoding both bombesin-related peptides and each of the mRNAs encoding their receptors are expressed in rat AP tissue. NMB mRNA is more prominent than GRP mRNA in all AP-like tissues examined (fresh AP, estradiol-treated reaggregate AP cell cultures and GH3 cells). NMB-R mRNA and GRP-R mRNA are both present in low levels in fresh AP whereas the GRP-R mRNA is predominant in GH3 cells and estradiol treated AP reaggregate cell cultures. Compared to fresh AP tissue, NMB mRNA and GRP-R mRNA expression is enhanced in estradiol-treated reaggregate cell cultures.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Regulação da Expressão Gênica , Neurocinina B/análogos & derivados , Peptídeos/genética , Adeno-Hipófise/metabolismo , Receptores da Bombesina/genética , Animais , Sondas de DNA , Estradiol/farmacologia , Peptídeo Liberador de Gastrina , Masculino , Neurocinina B/biossíntese , Neurocinina B/genética , Biossíntese Peptídica , Neoplasias Hipofisárias/química , Neoplasias Hipofisárias/patologia , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptores da Bombesina/biossíntese , Ribonucleases/metabolismo , Células Tumorais Cultivadas
20.
Eur J Cancer Prev ; 2 Suppl 3: 3-10, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8298449

RESUMO

DCIS and LCIS are different breast diseases at various points of view. DCIS has in most cases a clinical or mammographical pattern, whereas LCIS represents an incidental finding in breast tissue removed for another reason. However, DCIS found incidental to benign disease may be a more innocuous form of tumour. Multifocal foci are more frequent in LCIS than in DCIS, but microinvasion and coexisting unsuspected infiltration carcinoma are more often found in DCIS. Contralateral in situ breast carcinoma is a rare event in DCIS. It is seldom found in LCIS. The risk of development of an infiltrating ipsilateral carcinoma after biopsy or excision showing in situ carcinoma is higher for DCIS than for LCIS. However, in most cases the invasive tumour occurs at or near the site of the original biopsy. Among LCIS patients, invasive carcinoma occurs anywhere in the breast parenchyma. The risk of development of contralateral invasive cancer is very low in DCIS patients, but it is high in LCIS patients. It may be lobular, ductal or a mixture of different types. DCIS has to be considered as a truly preinvasive lesion although LCIS is rather a marker of increased risk.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma in Situ/epidemiologia , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Lobular/epidemiologia , Neoplasias da Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Fatores de Risco
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