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1.
Environ Monit Assess ; 193(11): 730, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34661752

RESUMO

The presence of heavy metals and naturally occurring radioactive materials (NORMs) in high concentrations in soils can be hazardous to exposed humans. This study is aimed at measuring the concentrations of heavy metals (Cu, Pb, Ni, Zn, Cd, Co, and Cr) and activity concentration of 232Th, 238U, and 40K in soils affected by and around a solid waste dumpsite in Osogbo metropolis, Nigeria. Atomic absorption spectrometry and gamma-ray spectrometric techniques were used to determine the concentrations of metals and NORMs, respectively. Possible environmental impact of the heavy metal content and the probable radiological hazard by the NORMs to the general public were assessed. The calculated pollution indices reported in this work for Co, Cr, Pb, and Ni show low pollution status. Geoaccumulation indices for Cu, Zn, and Cd indicated that the area under study is strongly contaminated by these metals. Evaluated ecological risk index narrowed down Cd as the poisonous metal with high concentration. The measured radionuclides' mean activity concentrations and the evaluated mean of radium equivalent and absorbed dose rate values are higher than the recommended safe limit, an indication of possible radiological hazard. The principal factor analysis results explained 76% of the collection of data and described chips of galvanized/chrome metals, scrap metals, waste from electronics, Cr, and Cd-containing waste as sources of the heavy metals. The practice of land cultivation around the dumpsite should be deterred to prevent the transportation of these vicious heavy metals into the food chain.


Assuntos
Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Nigéria , Radioisótopos , Medição de Risco , Solo , Poluentes do Solo/análise , Resíduos Sólidos
2.
J Appl Clin Med Phys ; 19(4): 68-74, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29756261

RESUMO

PURPOSE: Source strength (Sk ), sizes of vaginal cylinder applicators (VCA), number of dwell positions (DPs), and the prescribed dose (D) are basic parameters in brachytherapy (BT) treatment planning contributing to total dwell time (TDT). This study was aimed at assessing the relationships between the specified variables in an attempt to verify the TDT in high-dose-rate (HDR) vaginal cylinder applications. METHODS: One hundred and twenty-one patients treated with Gynesource-Co60 (Bebig, Germany) using VCAs of diameters 20, 25, and 30 mm at University College Hospital, Nigeria, were enrolled in this study. Brachytherapy doses ranging from 3 to 7 Gy were always prescribed to points 5 mm away from the cylinder's surface. Treatment planning was undertaken on HDR-Basic treatment planning system (TPS) which utilizes source step size of 5 mm. Data on the stated parameters related to the first BT fractions of the patients were acquired. With the aid of EViews statistical software, two forms of mathematical models were thereafter developed. The resulting TDTs from the models were compared with the TPS values using Minitab statistical software. RESULTS: The relationships obtained for the increasing sizes of the VCA were TDT1(min)=2.22+3.17DSk;TDT1(min)=3.52+3.74DSk;TDT1(min)=-1.96+6.91DSkandTDT2(min)=0.50-0.03Sk+0.02D+0.55DPs;TDT2(min)=7.08-0.06Sk+0.02D+0.67DPs;TDT2(min)=7.02-0.11Sk+0.03D+1.25DPs The model-based TDTs correlate with the TPS-calculated values with r1 = 0.80 (P = 0.412) and r2 = 0.97 (P = 0.468). CONCLUSIONS: The findings of this study could suggest likely variations in the treatment time when certain changes occur in the related parameters. The increasing size of the vaginal cylinder has a positive influence on the brachytherapy treatment time. The latter model has been a useful tool in the verification of the dose delivery time at the first HDR brachytherapy center in Nigeria and West Africa.


Assuntos
Braquiterapia , Feminino , Humanos , Nigéria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Vagina
3.
J Biomol Struct Dyn ; 41(22): 13015-13028, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36729100

RESUMO

The low constitutive activation of Liver X receptor, an endogenous nuclear receptor with two subtypes (α and ß), is a condition lying at the crossroad of cancer and cardiovascular disease. Both natural and synthetic Liver X receptor agonists have reportedly shown remarkable antiproliferative and atheroprotective effects but the repeated doses of its synthetic ones are also paradoxically associated with hyperlipidaemic effects and neurotoxicity, though attributed to the alpha subtype. This highlights the need for novel, safe, and potent LXR-beta-selective agonists. Hypocholesterolaemic effects of black theaflavins have been widely reported, but data on the exact theaflavin compound (s) responsible for these effects is currently lacking. Neither is information on the possible modulatory effects of the compound (s) on LXR-beta nor its possible implications in the context of drug development for cardiovascular diseases and cancers is explored. On this account, we investigated the potential interaction of four main theaflavin monomers (TF1, TF2A, TF2B & TF3) with human LXR-beta through robust computational modelling that entails molecular docking, free energy calculations and molecular dynamics simulations. The ligands were further profiled (in silico) for absorption, distribution, metabolism, excretion, and toxicological properties. Our result revealed theaflavin TF2B as a putative LXR-beta agonist, possibly responsible for the widely observed hypocholesterolaemic effect in black tea. This finding, while encouraging, needs to be experimentally verified in wet studies.Communicated by Ramaswamy H. Sarma.


Assuntos
Camellia sinensis , Chá , Humanos , Receptores X do Fígado , Simulação de Acoplamento Molecular , Antioxidantes/farmacologia , Simulação de Dinâmica Molecular
4.
JCO Glob Oncol ; 9: e2200221, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36921242

RESUMO

PURPOSE: To examine cancer patients' perspectives on the impact of COVID-19 on teleoncology in Nigeria. METHODS: Data from a multicenter survey conducted at 15 outpatient clinics to 1,097 patients with cancer from April and July 2020 were analyzed. The study outcome was telemedicine, defined as patients who reported their routine follow-up visits were converted to virtual visits because of COVID-19 (coded yes/no). Covariates included patient age, ethnicity, marital status, income, cancer treatment, service disruption, and cancer diagnosis/type. Stata/SE.v.17 (StataCorp, College Station, TX) was used to perform chi-square and logistic regression analyses. P values ≤ .05 were considered statistically significant. RESULTS: The majority of the 1,097 patients with cancer were female (65.7%) and age 55 years and older (35.0%). Because of COVID-19, 12.6% of patients' routine follow-ups were converted to virtual visits. More patients who canceled/postponed surgery (17.7% v 7.5%; P ≤ .001), radiotherapy (16.9% v 5.3%; P ≤ .001), and chemotherapy (22.8% v 8.5%; P ≤ .001), injection chemotherapy (20.6% v 8.7%; P ≤ .001) and those who reported being seen less by their doctor/nurse (60.3% v 11.4%; P ≤ .001) reported more follow-up conversions to virtual visits. In multivariate analyses, patients seen less by their doctors/nurses were 14.3 times more likely to have their routine follow-ups converted to virtual visits than those who did not (odds ratio, 14.33; 95% CI, 8.36 to 24.58). CONCLUSION: COVID-19 caused many patients with cancer in Nigeria to convert visits to a virtual format. These conversions were more common in patients whose surgery, radiotherapy, chemotherapy, and injection chemotherapy treatments were canceled or postponed. Our findings suggest how COVID-19 affects cancer treatment services and the importance of collecting teleoncological care data in Nigeria.


Assuntos
COVID-19 , Neoplasias , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Neoplasias/terapia , Instituições de Assistência Ambulatorial , Etnicidade
5.
Heliyon ; 8(7): e09831, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35815137

RESUMO

Improper sitting positioning of cemeteries in Nigeria is mostly responsible for groundwater pollution. Poor water quality may lead to some communicable diseases in most rural and urban areas of the southwestern part of Nigeria. The environmental impact of cemeteries close to residential areas within the Edunabon metropolis, southwestern part of Nigeria, was assessed. The research is aimed to understand the impact (if any) of the cemetery on the quality of water and soil within the vicinity and to investigate the suitability of soil materials underlying the cemetery as a special lining material. An integrated approach using geotechnical characterization, vertical electrical sounding and groundwater quality assessment was used in the present study. The geotechnical test involved six bulk undisturbed soil samples taken from two borrow pits within the cemetery. Index property tests (grain size distribution, specific gravity, natural moisture content, and Atterberg limits), engineering property tests (compaction test), X-ray diffraction, and X-ray fluorescence tests were carried out on the soil samples with their porosities and permeability estimated according to BS 1377. The majority of the study area is a wetland with a topography that descends into a gaining stream around 10 m from the cemetery. The soil of the cemetery is made up of coarse-grained porous lateritic soil, clay, and silt (0.22-3.88 percent), with a significant amount of gravel/sand (73.50-83.96 percent). Except in the control well, water analysis revealed a high total coliform concentration of 14-89 and a total hardness of 86-380 mg/L. When compared to the World Health Organization (WHO) drinking water standard and the Nigerian drinking water standard, the majority of cation concentrations were greater than the safe limits. The depth to contamination correlates to the depth of the aquifer in the research region, according to the results of electrical resistivity. Because of the narrow unsaturated zone, the study found that the position of the cemetery has a high risk of environmental impact on its near vicinity.

6.
JCO Glob Oncol ; 8: e2100244, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35157511

RESUMO

PURPOSE: Because of the global COVID-19 pandemic, health care organizations introduced guidelines for modifications to health and cancer medical care delivery to mitigate transmission and ensure quality health outcomes. To examine the extent and impact of these modifications on oncology service disruptions in Nigeria, we surveyed oncology patients across selected public and private cancer treatment centers. MATERIALS AND METHODS: Participating in the study were 15 tertiary cancer treatment centers across 12 Nigerian states. We recruited adult patients with cancer (18+ years) on active treatment to complete a self-administered survey on cancer care during COVID-19. We conducted descriptive and multivariate data analysis using Stata 16.1. RESULTS: Respondents were (n = 1,072), female (65.7%), ages 18-49 years (50.3%), and married (80.7%). The top two cancers were breast and prostate. Overall, 17.3% of respondents reported disruptions to cancer care, and more than half (51.0%) reported difficulties accessing care. Changes in chemotherapy regimens or route of administration were reported in 8.4% of respondents. Odds for any disruption were highest for older patients, western states, patients with prostate cancer, and patients with two or more flu symptoms. Odds for radiotherapy cancellation were highest for older patients, those with prostate cancer, and those with medium service perception. CONCLUSION: This study investigated COVID-19-influenced cancer treatment disruptions in Nigeria. Patients with cancer experienced significant disruptions to cancer care. Vulnerable patients are most likely to be negatively affected. Policies and strategies aimed at minimizing service disruptions while maintaining cancer patients' safety should be a priority for all health care institutions in the COVID-19 era.


Assuntos
COVID-19 , Neoplasias , Adolescente , Adulto , Feminino , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Nigéria/epidemiologia , Pandemias , SARS-CoV-2 , Adulto Jovem
7.
Curr Genet ; 56(5): 447-65, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20635087

RESUMO

Tra1 is a component of the Saccharomyces cerevisiae SAGA and NuA4 complexes and a member of the PIKK family, which contain a C-terminal phosphatidylinositol 3-kinase-like (PI3K) domain followed by a 35-residue FATC domain. Single residue changes of L3733A and F3744A, within the FATC domain, resulted in transcriptional changes and phenotypes that were similar but not identical to those caused by mutations in the PI3K domain or deletions of other SAGA or NuA4 components. The distinct nature of the FATC mutations was also apparent from the additive effect of tra1-L3733A with SAGA, NuA4, and tra1 PI3K domain mutations. Tra1-L3733A associates with SAGA and NuA4 components and with the Gal4 activation domain, to the same extent as wild-type Tra1; however, steady-state levels of Tra1-L3733A were reduced. We suggest that decreased stability of Tra1-L3733A accounts for the phenotypes since intragenic suppressors of tra1-L3733A restored Tra1 levels, and reducing wild-type Tra1 led to comparable growth defects. Also supporting a key role for the FATC domain in the structure/function of Tra1, addition of a C-terminal glycine residue resulted in decreased association with Spt7 and Esa1, and loss of cellular viability. These findings demonstrate the regulatory potential of mechanisms targeting the FATC domains of PIKK proteins.


Assuntos
Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Domínios e Motivos de Interação entre Proteínas , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Oxirredutases do Álcool/genética , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Análise Mutacional de DNA , DNA Fúngico/genética , DNA Fúngico/metabolismo , Proteínas de Ligação a DNA/genética , Expressão Gênica , Perfilação da Expressão Gênica , Histona Acetiltransferases/metabolismo , Mutação , Fosfatidilinositol 3-Quinase , Mutação Puntual , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Deleção de Sequência , Transativadores/química , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica , Ativação Transcricional
8.
Genetics ; 177(1): 151-66, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17660562

RESUMO

Tra1 is an essential component of the Saccharomyces cerevisiae SAGA and NuA4 complexes. Using targeted mutagenesis, we identified residues within its C-terminal phosphatidylinositol-3-kinase (PI3K) domain that are required for function. The phenotypes of tra1-P3408A, S3463A, and SRR3413-3415AAA included temperature sensitivity and reduced growth in media containing 6% ethanol or calcofluor white or depleted of phosphate. These alleles resulted in a twofold or greater change in expression of approximately 7% of yeast genes in rich media and reduced activation of PHO5 and ADH2 promoters. Tra1-SRR3413 associated with components of both the NuA4 and SAGA complexes and with the Gal4 transcriptional activation domain similar to wild-type protein. Tra1-SRR3413 was recruited to the PHO5 promoter in vivo but gave rise to decreased relative amounts of acetylated histone H3 and histone H4 at SAGA and NuA4 regulated promoters. Distinct from other components of these complexes, tra1-SRR3413 resulted in generation-dependent telomere shortening and synthetic slow growth in combination with deletions of a number of genes with roles in membrane-related processes. While the tra1 alleles have some phenotypic similarities with deletions of SAGA and NuA4 components, their distinct nature may arise from the simultaneous alteration of SAGA and NuA4 functions.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Alelos , Western Blotting , Imunoprecipitação da Cromatina , DNA Fúngico/genética , DNA Fúngico/metabolismo , Perfilação da Expressão Gênica , Histona Acetiltransferases , Mutação/genética , Fenótipo , Fosfatidilinositol 3-Quinases/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Telômero/fisiologia , beta-Galactosidase/metabolismo
10.
BMC Biochem ; 8: 16, 2007 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-17686179

RESUMO

BACKGROUND: Spt7 is an integral component of the multi-subunit SAGA complex that is required for the expression of approximately 10% of yeast genes. Two forms of Spt7 have been identified, the second of which is truncated at its C-terminus and found in the SAGA-like (SLIK) complex. RESULTS: We have found that C-terminal processing of Spt7 to its SLIK form (Spt7SLIK) and to a distinct third form (Spt7Form3) occurs in the absence of the SAGA complex components Gcn5, Spt8, Ada1 and Spt20, the latter two of which are required for the integrity of the complex. In addition, N-terminally truncated derivatives of Spt7, including a derivative lacking the histone fold, are processed, indicating that the C-terminus of Spt7 is sufficient for processing and that processing does not require functional Spt7. Using galactose inducible Spt7 expression, we show that the three forms of Spt7 appear and disappear at approximately the same rate with full-length Spt7 not being chased into Spt7SLIK or Spt7Form3. Interestingly, reduced levels of Spt7SLIK and Spt7Form3 were observed in a strain lacking the SAGA component Ubp8, suggesting a regulatory role for Ubp8 in the truncation of Spt7. CONCLUSION: We conclude that truncation of Spt7 occurs early in the biosynthesis of distinct Spt7 containing complexes rather than being a dynamic process linked to the action of the SAGA complex in transcriptional regulation.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transativadores/deficiência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Aminoácidos/genética , Aminoácidos/metabolismo , Epitopos/imunologia , Deleção de Genes , Peso Molecular , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transativadores/genética , Fatores de Transcrição/genética
11.
J Biomol Tech ; 16(4): 316-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16522851

RESUMO

RNA isolation from yeast is complicated by the need to initially break the cell wall. While this can be accomplished by glass bead disruption or enzyme treatment, these approaches result in DNA contamination and/or the need for incubation periods. We have developed a protocol for the isolation of RNA samples from yeast that minimizes degradation by RNases and incorporates two purification steps: acid phenol extraction and binding to a silica matrix. The procedure requires no precipitation steps, facilitating automation, and can be completed in less than 90 min. The RNA quality is ideal for microarray analysis.


Assuntos
Biotecnologia/métodos , RNA Fúngico/isolamento & purificação , Saccharomyces cerevisiae/química , Dióxido de Silício/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fenol/farmacologia , RNA Fúngico/genética , Saccharomyces cerevisiae/genética , Dióxido de Silício/química
12.
Arch Inst Pasteur Tunis ; 55(3): 293-301, 1978 Sep.
Artigo em Francês | MEDLINE | ID: mdl-228619

RESUMO

With a view to detecting infections and carriage of human respiratory viruses in wild birds, 349 serum samples collected from 21 bird species -- sedentary ones and birds with large or limited migration areas -- were investigated. The following antigens were used: influenza virus A/Hong Kong 1/68 (H3N2)), A2 England 42/73 (H3N2), A2 Victoria 3/75 (H3N2), A/New Jersey 8/76 (HswN1), B/Hong Kong 5/72; parainfluenza virus type I Sendai and type II, coronavirus OC/43. An elevated incidence of antibodies to A2 Victoria 3/75 (H3N2) and parainfluenza type I virus was detected in herons (Ardea cinerea, Nyctycorax myctycorax). The high incidence of antibodies to B/Hong Kong 5/72 (30.7% of the samples exhibited significant titers) found in the crow (Corvus corone sardonius) is ascribed to the fact that this bird is carnivorus, feeding on corpses of mammals.


Assuntos
Aves , Reservatórios de Doenças , Infecções Respiratórias/transmissão , Viroses/transmissão , Animais , Europa Oriental , Humanos , Influenza Humana/transmissão , Infecções por Paramyxoviridae/transmissão , Romênia
13.
Mol Genet Genomics ; 277(5): 491-506, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17447102

RESUMO

In Saccharomyces cerevisiae histone H2B is ubiquitylated at lysine 123 in a process requiring the E2-ubiquitin conjugase, Rad6. We have analyzed gene expression in a strain containing a variant of histone H2B with lysine 123 converted to arginine to address the mechanisms by which ubiquitylation and deubiquitylation of histone H2B affect gene expression. The SAGA complex component, Ubp8, is one of two proteases that remove the ubiquitin moiety at lysine 123. We show that changes in gene expression observed upon deletion of ubp8 are suppressed by htb1 ( K123R ), which provides genetic evidence that Ubp8 alters gene expression through deubiquitylation of histone H2B. Microarray analyses of the htb1 ( K123R ) strain show that loss of histone ubiquitylation results in a twofold or greater change in expression of approximately 1.5% of the protein coding genes with approximately 75% of these increasing. For genes in which ubiquitylation represses expression, ubiquitylation principally acts through its effects on histone methylation. In contrast, decreased expression of the CWP1 gene was not paralleled by deletions of methyltransferase components and is thus likely independent of methylation. Finally, by comparing gene expression changes in the htb1 ( K123R ) strain with those in a strain deleted for rad6, we conclude that lysine 123 affects transcription primarily because of it being a site of ubiquitylation.


Assuntos
Regulação Fúngica da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Saccharomyces cerevisiae/genética , Ubiquitina/metabolismo , Substituição de Aminoácidos , Sistemas de Transporte de Aminoácidos/genética , Arginina/genética , Arginina/metabolismo , Endopeptidases/genética , Endopeptidases/metabolismo , Histona-Lisina N-Metiltransferase , Lisina/genética , Lisina/metabolismo , Glicoproteínas de Membrana/genética , Metilação , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Virologie ; 40(4): 285-95, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2561502

RESUMO

The report is a review of the research and results of the "Stefan S. Nicolau" Institute of Virology scientists in the field of herpes viruses, as they were materialized in the great number of published or communicated scientific papers these last ten years.


Assuntos
Academias e Institutos , Simplexvirus , Virologia , Animais , Transformação Celular Viral , Modelos Animais de Doenças , Genes Virais , Herpes Simples/diagnóstico , Herpes Simples/imunologia , Herpes Simples/microbiologia , Herpes Simples/terapia , Humanos , Pesquisa , Romênia , Simplexvirus/genética , Simplexvirus/imunologia , Simplexvirus/patogenicidade
16.
Virologie ; 30(2): 95-101, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-223281

RESUMO

A rapid, easy-to-perform and specific technique for the visualization of herpes simplex virus (HSV)-induced cell surface antigens is described. The technique consists in the incubation of HSV-infected cells with hyperimmune HSV antiserum and formation of rosettes with FITC-labelled Cowan strain staphylococci containing protein A. The "nonspecific background" of the reaction can be estimated by comparison with the rate of bacteria binding by control cells not incubated with HSV antiserum.


Assuntos
Antígenos de Superfície/análise , Simplexvirus/imunologia , Proteína Estafilocócica A/imunologia , Células Cultivadas , Embrião de Mamíferos , Imunofluorescência , Células HeLa , Humanos , Formação de Roseta
17.
Rom J Virol ; 49(1-4): 27-42, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10892424

RESUMO

In this work are reported the results of the researches performed by the authors more than a decade ago, aimed at assessing the clinical benefit of the introduction of the drug "Zovirax" in the treatment of recurrent herpetic infections with genital or ocular location. The results of the treatment carried out on a restricted group of patients were positive both in cases of genital herpes and of herpetic keratitis. The clinical benefit consisted in the reduction of the mean duration of the disease, in the shortening of the period of the infective virus elimination from the lesion, as well as in the decrease of the intensity and duration of the clinical symptomatology as a whole. With respect to these clinical parameters, the observations of the authors performed on a low number of cases are consistent with the data obtained by other authors in the framework of more extensive studies. The renewed discussion of these clinical and laboratory observations carried out by the authors during the first years after the introduction in our country of this drug in the therapeutic arsenal of herpetic infections is aimed at establishing a landmark for the comparison with more recent results of similar studies, starting from the idea of the opportunity of assessing periodically the sensitivity of herpes simplex virus strains, circulating among the autochthonous population, to the inhibitory action of some antiviral drugs. In other words, the in vitro testing of the susceptibility of these strains to the chemotherapeutic agents in current use is predictive for the efficacy degree of these drugs in the treatment of some forms of herpetic infections. This evaluation represents at the same time, undoubtedly, a useful epidemiological surveillance means of the circulation of human herpes viruses among the population. We refer especially to the risk of appearance of pharmacoresistant mutants, a risk possible under the conditions of the increased access of patients to the antiviral chemotherapeutic medication, which implicitly augments the probability of a fortuitous administration of treatments insufficient as regards the dose or the duration. In this work there are also shown the results regarding some experimental aspects related to the immune control mechanisms of the herpetic infection, which may complement the chemotherapeutic action. Under the treatment with acycloguanosine the synthesis of herpetic antigens is kept at a level sufficient for the circulating antibody synthesis induction and the HSV infected cells treated with the drug are recognized and lysed by effectors of the cell-mediated immune response of the host. Hence, it may be asserted that, in some clinical cases of recurrent herpes with frequent episodes, it is useful to perform immunostimulating treatments, able to potentiate the cell-mediated immune mechanisms possibly involved in the limitation of the herpetic infection at the peripheral level and of its spreading in the central nervous system.


Assuntos
Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Herpes Genital/tratamento farmacológico , Ceratite Herpética/tratamento farmacológico , Aciclovir/farmacologia , Adulto , Animais , Anticorpos Antivirais/sangue , Antivirais/farmacologia , Células Cultivadas , Feminino , Fibroblastos , Herpes Genital/virologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/isolamento & purificação , Humanos , Imunização , Ceratite Herpética/virologia , Masculino , Camundongos , Recidiva
18.
Rom J Virol ; 49(1-4): 117-39, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10892432

RESUMO

Mice distributed in groups were inoculated with the herpes virus simplex type 1 and type 2 strains in various dilutions (10(-1)-10(-7)), which had been maintained on primary human embryo cell cultures. The animals were killed and homogenates were prepared of their brains, which were used for testing the infective titre in vivo and for the isolation of nuclei, by means of the Hymer-Kuff technique. For the cytokaryological examinations, smears were prepared from the homogenate, which were stained by May-Grünwald-Giemsa and Mann methods. The cell and nucleus types were evaluated morphologically, descriptively, according to the size and structure. On the basis of three criteria the following groups were set up: large sized cells with bulky nuclei; middle sized cells with nuclei of a medium size; small sized cells with small nuclei and visible nucleoli; small sized cells with small, tachychromatic nuclei; cells exhibiting karyolysis. In both the infection with herpes virus simplex type 1 and type 2, the small sized cells with small tachychromatic nuclei represent the highest rate. Between the variants of the elaborated models no significant differences regarding the cell and nucleus types are recorded. On the whole, the cytokaryological picture does not exhibit notable differences, but rather resemblances with respect to the proportionality of the nucleus types in the experimental variants studied, in the case of herpes simplex virus type 1 and 2 induced infections.


Assuntos
Encéfalo/ultraestrutura , Núcleo Celular/ultraestrutura , Herpes Simples/patologia , Herpesvirus Humano 1/patogenicidade , Herpesvirus Humano 2/patogenicidade , Animais , Encéfalo/citologia , Cariometria , Masculino , Camundongos , Neurônios/ultraestrutura
19.
Rom J Virol ; 48(1-4): 61-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9836328

RESUMO

In the present work there are described some spectral characteristics in the ultraviolet and infrared region under various environment conditions for a series of synthetic analogues of deoxyguanosine, substances possessing antiviral properties. The study is performed on the Acyclovir compounds and on its Na, K and Li salts, synthetized in Romania, in comparison with the similar product Zovirax, of the "Wellcome" firm (England), used in the clinical practice for several years. The results show a very marked resemblance of the spectral behavior for all these products, a conclusion confirmed by the similar biological effects in the herpetic infection.


Assuntos
Aciclovir/farmacologia , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Fluorescência , Humanos , Espectrofotometria Ultravioleta
20.
Virologie ; 30(3): 179-83, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-231859

RESUMO

Surface antigens induced by herpes simplex virus infection in HeLa cells remain unaltered after treatment of the cells with 2% formalin for 10 min or with 0.08% trypsin for 15 min at 37 degrees C. A longer trypsin treatment (for 1 hour) will cause gradual alterations in the virus-induced antigens. Hence, these antigens are proteins deeply implanted within the cellular membrane. Their mobility--optimal at 37 degrees C--allows aggregation of the antigens in the form of caps or patches by polyvalent ligands such as IgG.


Assuntos
Antígenos de Superfície/análise , Antígenos Virais/análise , Simplexvirus/imunologia , Formaldeído/farmacologia , Células HeLa , Staphylococcus , Tripsina/farmacologia , Cultura de Vírus
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