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1.
Braz J Med Biol Res ; 56: e12922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970922

RESUMO

Nuclear proliferation marker MIB-1 (Ki-67) immunohistochemistry (IHC) is used to examine tumor cell proliferation. However, the diagnostic or prognostic value of the Ki-67 nuclear staining intensity and location, defined as nuclear gradient (NG), has not been assessed. This study examined the potential association between Ki-67 NG and cell cycle phases and its effect on the prognosis of pulmonary typical carcinoid (PTC) tumors. We propose a method for classifying the NG of Ki-67 during the cell cycle and compare the results between PTC, pulmonary adenocarcinoma (PAD), and breast ductal carcinoma (BDC). A literature review and objective analysis of IHC-stained paraffin sections were used to determine the Ki-67 labeling index and composed a stratification of the NG into NG1, NG2, and NG3/4 categories. A semi-automated image analysis protocol was established to determine the Ki-67 NG in PTC, PAD, and BDC. High intraobserver consistency and moderate interobserver agreement were achieved in the determination of Ki-67 NG in tumor specimens. NG1 and NG2 were lower in PTC than in PAD and BDC. Cox multivariate analysis of PTC after adjusting for age and number of metastatic lymph nodes showed that Ki-67 NG1 and NG2 significantly predicted clinical outcomes. The semi-automated method for quantification of Ki-67 nuclear immunostaining proposed in this study could become a valuable diagnostic and prognostic tool in PTC.


Assuntos
Antígeno Ki-67 , Imuno-Histoquímica , Antígeno Ki-67/metabolismo
2.
Braz. j. med. biol. res ; 56: e12922, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520463

RESUMO

Nuclear proliferation marker MIB-1 (Ki-67) immunohistochemistry (IHC) is used to examine tumor cell proliferation. However, the diagnostic or prognostic value of the Ki-67 nuclear staining intensity and location, defined as nuclear gradient (NG), has not been assessed. This study examined the potential association between Ki-67 NG and cell cycle phases and its effect on the prognosis of pulmonary typical carcinoid (PTC) tumors. We propose a method for classifying the NG of Ki-67 during the cell cycle and compare the results between PTC, pulmonary adenocarcinoma (PAD), and breast ductal carcinoma (BDC). A literature review and objective analysis of IHC-stained paraffin sections were used to determine the Ki-67 labeling index and composed a stratification of the NG into NG1, NG2, and NG3/4 categories. A semi-automated image analysis protocol was established to determine the Ki-67 NG in PTC, PAD, and BDC. High intraobserver consistency and moderate interobserver agreement were achieved in the determination of Ki-67 NG in tumor specimens. NG1 and NG2 were lower in PTC than in PAD and BDC. Cox multivariate analysis of PTC after adjusting for age and number of metastatic lymph nodes showed that Ki-67 NG1 and NG2 significantly predicted clinical outcomes. The semi-automated method for quantification of Ki-67 nuclear immunostaining proposed in this study could become a valuable diagnostic and prognostic tool in PTC.

3.
Plant Biol (Stuttg) ; 23(6): 1109-1117, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34532953

RESUMO

Knowledge of plant responses to environmental heterogeneity during ontogeny is important to elucidate the changes that occur to promote resource capture in tropical forests. We tested the hypothesis that expression changes in leaf metamer traits of Brazilian rosewood (Dalbergia nigra), from seedlings to emergent canopy trees, occur as new microclimate environments are achieved. We also tested the hypothesis that increased light heterogeneity in the understorey leads to higher plasticity in leaf traits of seedlings and saplings than in sun-exposed metamers of emergent trees subject to stressful conditions. We compared leaf metamer traits of 53 individuals including seedlings, saplings and emergent trees. We also evaluated the light heterogeneity in vertical strata and the variations in leaf traits within individuals (among metamers of the same individual). These were associated with height of the individuals. Compared to understorey plants, emergent trees presented larger metamers, with lower specific leaf area (SLA), lower investment in leaf area per total dry mass of metamer (LARm ), lower specific petiole length (SPL) and lower specific internode length (SIL). Higher phenotypic variation within individuals was observed in seedlings, which decreased as the trees grew taller. The results suggest the integration of ontogenetic changes in leaf traits under new microclimate conditions as the plants reach different vertical strata in the forest. Additionally, our results support the hypothesis that increased light heterogeneity in the understorey shaped higher phenotypic variation within individuals in juveniles and that stressful conditions in sun-exposed leaf metamers of emergent trees led to increased phenotypic stability.


Assuntos
Folhas de Planta , Árvores , Florestas , Plântula , Madeira
4.
Braz J Microbiol ; 52(4): 1835-1843, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34561846

RESUMO

Baculoviruses have been applied for biocontrol of agricultural pests, such as velvetbean caterpillar (Anticarsia gemmatalis) and fall armyworm (Spodoptera frugiperda). Cell culture is an interesting approach for large-scale production of these viruses. Co-infection of a host cell with two distinct viruses can contribute to reduce costs due to saving cell culture media, bioreactor space and the resulting co-occluded polyhedra may help to reduce final biopesticide costs. The baculovirus Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) and Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) were chosen to test a model for in vitro co-infection in SF21 cells. Different proportions of SfMNPV/AgMNPV were evaluated along three in vitro passages by optical microscopy analysis of cells and real-time PCR (qPCR) of DNA obtained from budded viruses (BVs) and occlusion bodies (OBs). The kinetics of viral protein synthesis was carried out for analysis of the co-infection in first passage and bioassays with the resulting OBs were performed against A. gemmatalis and S. frugiperda larvae. The results demonstrated successful co-infection in these cells. The quantity of SfMNPV and AgMNPV in supernatants and sediments tends to be maintained stable during the three passages, although the amount of AgMNPV was higher than SfMPNV in most of the experiments. Analysis of the kinetics of radiolabed proteins showed that the cell protein synthesis was shut off and two distinct bands of about 30 kDa, regarded to be the polyhedrin of each virus, were strongly detected at 48 and 72 hp.i. Although the pathogenicity of the produced viruses was not completely satisfactory, the bioassays confirmed occurrence of co-infected larvae with disproportional amount of each virus.


Assuntos
Microbiologia Industrial , Nucleopoliedrovírus , Spodoptera , Virologia , Animais , Microbiologia Industrial/métodos , Microbiologia Industrial/tendências , Larva/virologia , Nucleopoliedrovírus/fisiologia , Células Sf9 , Spodoptera/virologia , Virologia/métodos , Virologia/tendências
5.
J Invertebr Pathol ; 164: 23-31, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30930188

RESUMO

Baculovirus natural populations are known to be genetically heterogeneous and such genotypic diversity could have implications in the performance of biocontrol agents. The Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) has been widely used to control the velvetbean caterpillar, Anticarsia gemmatalis, in Brazil. In the present work, morphological and molecular analyses as well as the biological activity of AgMNPV genotypes derived from a Brazilian field isolate (AgMNPV-79) were carried out. The existence of genotypic variants in the population was confirmed by DNA restriction analysis. Although difference in virulence was observed among the variants, the most (Ag79-01) and the least (AgL-16) virulent clones do not show any morphological and cytopathological changes when compared to the most studied isolate (AgMNPV-2D). The complete genome analysis of the two viral clones showed the presence of single open reading frames (ORFs) of the pe-38 and he65 genes, which contrasts with the two split ORFs present in the genome of the AgMNPV-2D isolate. The viral clone AgL-16 has many variations in the ie-2 and pe-38 genes, which are transcription regulatory genes responsible for the regulation of viral early gene expression during insect cell infection. Furthermore, other genes showed alterations like the odv-e56, which have an essential role in the maturation and envelopment of the ODVs, and bro-a and bro-b genes which were fused to form a single ORF. For the Ag79-01, although the total number of single nucleotide variants (SNVs) was more prominent in the pe-38 gene, its genome showed very few modifications in comparison to the AgMNPV-2D genome.


Assuntos
Lepidópteros/virologia , Nucleopoliedrovírus , Virulência/genética , Animais , Bioensaio , Linhagem Celular , Genes Virais , Variação Genética , Genoma Viral , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/patogenicidade , Nucleopoliedrovírus/ultraestrutura , Controle Biológico de Vetores , Filogenia , Células Sf9
6.
BMC Genomics ; 19(1): 698, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30249206

RESUMO

BACKGROUND: Erinnyis ello granulovirus (ErelGV) is a betabaculovirus infecting caterpillars of the sphingid moth E. ello ello (cassava hornworm), an important pest of cassava crops (Manihot esculenta). In this study, the genome of seven field isolates of the virus ErelGV were deep sequenced and their inter- and intrapopulational sequence diversity were analyzed. RESULTS: No events of gene gain/loss or translocations were observed, and indels were mainly found within highly repetitive regions (direct repeats, drs). A naturally occurring isolate from Northern Brazil (Acre State, an Amazonian region) has shown to be the most diverse population, with a unique pattern of polymorphisms. Overall, non-synonymous substitutions were found all over the seven genomes, with no specific gathering of mutations on hotspot regions. Independently of their sizes, some ORFs have shown higher levels of non-synonymous changes than others. Non-core genes of known functions and structural genes were among the most diverse ones; and as expected, core genes were the least variable genes. We observed remarkable differences on diversity of paralogous genes, as in multiple copies of p10, fgf, and pep. Another important contrast on sequence diversity was found on genes encoding complex subunits and/or involved in the same biological processes, as late expression factors (lefs) and per os infectivity factors (pifs). Interestingly, several polymorphisms in coding regions lie on sequences encoding specific protein domains. CONCLUSIONS: By comparing and integrating information about inter- and intrapopulational diversity of viral isolates, we provide a detailed description on how evolution operates on field isolates of a betabaculovirus. Our results revealed that 35-41% of the SNPs of ErelGV lead to amino acid changes (non-synonymous substitutions). Some genes, especially non-core genes of unknown functions, tend to accumulate more mutations, while core genes evolve slowly and are more conserved. Additional studies would be necessary to understand the actual effects of such gene variations on viral infection and fitness.


Assuntos
Baculoviridae/genética , Genoma Viral , Polimorfismo Genético , Baculoviridae/classificação , Baculoviridae/isolamento & purificação , Filogenia , Proteínas Virais/genética
7.
Arq. bras. med. vet. zootec. (Online) ; 70(2): 637-640, mar.-abr. 2018.
Artigo em Português | LILACS, VETINDEX | ID: biblio-910980

RESUMO

The maintenance of wild animals in captivity can be a source for transmission of infectious and zoonotic diseases. In February 2016, blue-fronted amazon parrots that were kept at the Centro de Reabilitação de Animais Silvestres (CRAS) of Campo Grande - MS died suddenly. The specimens were sent to the Universidade Federal de Mato Grosso do Sul (UFMS), Faculdade de Medicina Veterinária e Zootecnia (FAMEZ) to be necropsied. Anatomopathological exams were performed and organ fragments from all systems were collected for histopathological exams. Liver and spleen fragments were also collected for bacteriological exams. Histopathological exam revealed bacterial aggregates distributed through the organs. Bacteriological exam isolated Salmonella spp. from the fragments of liver and spleen. The confirmation of the genus was made by serum agglutination on slide and by the polymerase chain reaction (PCR). The genetic sequencing identified the sample as Salmonella Typhimurium.(AU)


Assuntos
Animais , Amazona/microbiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/patogenicidade , Reação em Cadeia da Polimerase/veterinária
8.
Ceska Gynekol ; 80(2): 140-3, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25944604

RESUMO

OBJECTIVE: To describe a case of prenatal diagnosis of a giant placental chorioangioma with favorable outcome. DESIGN: A case report. SETTING: Gynecology and Obstetrics Service, Federal University of Triângulo Mineiro (UFTM), Uberaba-MG, Brazil. CASE REPORT: The placental chorioangioma is the most common benign tumor, but the type giant has a small prevalence, ranging from 1:16.000 to 1:50.000 pregnancies. We reported a case of a patient aged 18, pregnant for the first time, who performed a routine obstetric ultrasound was found to have polyhydramnios associated with placental vascular lesions suggestive of chorioangioma also was defined by fetal magnetic resonance imaging and confirmed by pathological examination.


Assuntos
Hemangioma/diagnóstico , Complicações Neoplásicas na Gravidez/diagnóstico , Ultrassonografia Pré-Natal , Adolescente , Diagnóstico Diferencial , Feminino , Hemangioma/diagnóstico por imagem , Hemangioma/patologia , Hemangioma/cirurgia , Humanos , Recém-Nascido , Doenças Placentárias , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/patologia
9.
Orthop Traumatol Surg Res ; 101(1): 83-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25541338

RESUMO

INTRODUCTION: Topical application of tranexamic acid to the knee joint before closure in total knee arthroplasty reduces postoperative bleeding without increase in complication. However, it is unknown the effectiveness of topic TXA performed with other topical medications, like povidone-iodine solution. MATERIALS AND METHODS: One hundred and twenty-five patients were randomized to receive 100mL of povidone-iodine solution (control: group A) or 1.5 (group B) and 3.0 g (group C) of topical TXA in povidone-iodine solution applied into the knee before closure in total knee arthroplasty. RESULTS: The patients in the TXA groups had higher mean postoperative hemoglobin levels (P=0.01 and P=0.03 in groups B and C, respectively) and a reduced postoperative blood loss in the TXA groups (P=0.07 and P=0.09 in groups B and C, respectively). No significant complications were observed. DISCUSSION: In this study, topical application of tranexamic acid after total knee arthroplasty together with povidone-iodine solution results in higher postoperative hemoglobin levels and lower blood loss compared with those in the control group without other complications. LEVEL OF EVIDENCE: I - I: high-powered prospective randomized trial.


Assuntos
Artroplastia do Joelho/efeitos adversos , Hemorragia Pós-Operatória/prevenção & controle , Povidona-Iodo/administração & dosagem , Ácido Tranexâmico/administração & dosagem , Administração Tópica , Idoso , Anti-Infecciosos Locais/administração & dosagem , Antifibrinolíticos/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos
11.
J Dent ; 41 Suppl 2: S35-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23985437

RESUMO

OBJECTIVE: To compare the efficacy of a new dentifrice containing 1.5% arginine and 1450 ppm fluoride to a positive control dentifrice containing 1450 ppm fluoride alone in arresting and reversing primary root caries lesions in adults. STUDY DESIGN: A total of 3779 subjects from Piracicaba, Säo Paulo, Brazil were screened; 284 had at least one leathery primary root caries lesion and were eligible for the study. The new dentifrice contained 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate; the matched positive control dentifrice contained 1450 ppm fluoride. One lesion for each subject was selected for inclusion in the study and was examined at baseline, 3 and 6 months. RESULTS: A total of 253 subjects completed the study with 129 of 144 subjects included in the final statistical analysis for the test dentifrice and 124 of 140 for the positive control. The mean age of subjects was 45.7 (±9.19) years and 56.5% were female. After 6 months product use, 70.5% of root caries lesions improved for subjects using the arginine-containing dentifrice compared to 58.1% for subjects using the positive control. The difference in the number of root caries lesions becoming hard in the two groups was statistically significant (p=0.038). CONCLUSION: A new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate, provided statistically significantly superior efficacy in arresting and reversing active root caries lesions in adults compared to a matched positive control dentifrice containing fluoride alone.


Assuntos
Arginina/uso terapêutico , Carbonato de Cálcio/uso terapêutico , Cariostáticos/uso terapêutico , Dentifrícios/uso terapêutico , Fluoretos/uso terapêutico , Fosfatos/uso terapêutico , Cárie Radicular/prevenção & controle , Adulto , Idoso , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Índice de Placa Dentária , Feminino , Seguimentos , Gengiva/patologia , Dureza , Humanos , Masculino , Pessoa de Meia-Idade , Cárie Radicular/patologia , Remineralização Dentária/métodos , Resultado do Tratamento
12.
Braz J Biol ; 67(1): 47-51, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17505749

RESUMO

In a benthic community on a continuous flat granite substrate in a third-order coastal forest stream, the dominant chironomid (Cricotopus) increased in number when shrimps (Macrobrachium olfersi and Potimirim glabra) and baetid ephemeropterans were excluded by electricity. The response appeared to be mediated by an increase in periphyton and sediments, rather than a reduction of direct predation or interference. Chironomids, periphyton and sediments decreased significantly compared to the control when shrimps only were excluded. Baetid ephemeropteran appeared to be the most important determinants of periphyton and sediment mass; the density of chironomids appeared to follow the quantity of periphyton and sediments.


Assuntos
Chironomidae/fisiologia , Ecossistema , Penaeidae/fisiologia , Comportamento Predatório/fisiologia , Animais , Brasil , Água Doce , Sedimentos Geológicos , Insetos/fisiologia , Densidade Demográfica
13.
Braz. j. biol ; 67(1): 47-51, Feb. 2007. graf, mapas
Artigo em Inglês | LILACS | ID: lil-449626

RESUMO

In a benthic community on a continuous flat granite substrate in a third-order coastal forest stream, the dominant chironomid (Cricotopus) increased in number when shrimps (Macrobrachium olfersi and Potimirim glabra) and baetid ephemeropterans were excluded by electricity. The response appeared to be mediated by an increase in periphyton and sediments, rather than a reduction of direct predation or interference. Chironomids, periphyton and sediments decreased significantly compared to the control when shrimps only were excluded. Baetid ephemeropteran appeared to be the most important determinants of periphyton and sediment mass; the density of chironomids appeared to follow the quantity of periphyton and sediments.


Os quironomídeos dominantes (Cricotopus) de uma comunidade bentônica aumentaram em densidade quando camarões (Macrobrachium olfersi e Potimirim glabra) e efemerópteros betídeos foram excluídos por eletricidade de um substrato rochoso contínuo em um córrego de Mata Atlântica. Esta resposta parece ter sido mais influenciada por um aumento no perifíton do que pela redução da predação direta ou competição por interferência. Quando somente os camarões foram excluídos, os quironomídeos, perifíton e sedimentos sofreram redução significativa em comparação com os controles. Efemerópteros betídeos parecem ter sido os maiores determinantes da quantidade de sedimentos e perifíton; a densidade de quironomídeos parece seguir a quantidade de perifíton e sedimentos.


Assuntos
Animais , Chironomidae/fisiologia , Ecossistema , Penaeidae/fisiologia , Comportamento Predatório/fisiologia , Brasil , Água Doce , Sedimentos Geológicos , Insetos/fisiologia , Densidade Demográfica
14.
Cancer Chemother Pharmacol ; 59(1): 71-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16708234

RESUMO

INTRODUCTION: Ifosfamide (IFS) is an antineoplastic alkylating agent whose major side effect is hemorrhagic cystitis (HC). This toxicity is attributed to the renal excretion of acrolein (ACR), a highly urotoxic IFS metabolite. Despite the clinical use of mesna to prevent HC, a significant percent ( approximately 33%) of patients present with at last one feature of HC, mainly hematuria. AIM: To investigate the use of two antioxidants-amifostine and glutathione-for the prevention of experimental IFS- and ACR-induced HC. MATERIALS AND METHODS: Male Swiss mice were treated intraperitoneal (i.p.) with saline (control), glutathione (125, 250 or 500 mg/kg) or amifostine (25, 50 or 100 mg/kg), and 30 min later they received a single i.p. injection of IFS at a dose of 400 mg/kg. To investigate the systemic effects of the antioxidants on ACR-induced HC, the animals were treated with saline, amifostine (50 mg/kg, i.p.) or glutathione (500 mg/kg, i.p.), and 30 min afterward with 75 mug ACR intravesically (i.ve.). In another set of experiments, the antioxidants were injected directly into the bladder, where the mice received a single i.ve injection of ACR (75 mug) plus amifostine (1.5 mg/kg) or glutathione (2 mg/kg). HC was measured 3 h after IFS or ACR injection according to bladder wet weight, macroscopic (edema and hemorrhage) and microscopic changes, i.e., edema, hemorrhage, cellular infiltration, fibrin deposition and urothelial desquamation. RESULTS: Pretreatments with amifostine or glutathione prevented IFS-induced HC in a dose-dependent manner. Furthermore, ACR-induced HC was also prevented by systemic (i.p.) or local (i.ve.) pretreatment with glutathione or amifostine. The greatest protective effect was seen with local amifostine treatment (2 mg/kg i.ve.) (P < 0.05). CONCLUSIONS: Glutathione and amifostine show a beneficial effect in experimental IFS- and ACR-induced HC. Thus, they should be investigated as an alternative treatment to prevent HC observed in patients undergoing IFS treatment.


Assuntos
Acroleína/antagonistas & inibidores , Acroleína/toxicidade , Amifostina/uso terapêutico , Antídotos/uso terapêutico , Antineoplásicos Alquilantes/antagonistas & inibidores , Antineoplásicos Alquilantes/toxicidade , Cistite/induzido quimicamente , Cistite/prevenção & controle , Glutationa/uso terapêutico , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Ifosfamida/antagonistas & inibidores , Ifosfamida/toxicidade , Protetores contra Radiação/uso terapêutico , Animais , Cistite/patologia , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/patologia , Edema/prevenção & controle , Hemorragia/patologia , Injeções Intraperitoneais , Injeções Intravenosas , Masculino , Camundongos , Bexiga Urinária/patologia
15.
Braz J Med Biol Res ; 39(11): 1475-81, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17146560

RESUMO

Acrolein is a urinary metabolite of cyclophosphamide and ifosfamide, which has been reported to be the causative agent of hemorrhagic cystitis induced by these compounds. A direct cytotoxic effect of acrolein, however, has not yet been demonstrated. In the present study, the effects of intravesical injection of acrolein and mesna, the classical acrolein chemical inhibitor, were evaluated. Male Swiss mice weighing 25 to 35 g (N = 6 per group) received saline or acrolein (25, 75, 225 microg) intravesically 3, 6, 12, and 24 h before sacrifice for evaluation of bladder wet weight, macroscopic and histopathological changes by Gray's criteria, and 3 and 24 h for assessment of increase in vascular permeability. In other animals, mesna was administered intravesically (2 mg) or systemically (80 mg/kg) 1 h before acrolein. Intravesical administration of acrolein induced a dose- and time-dependent increase in vascular permeability and bladder wet weight (within 3 h: 2.2- and 21-fold increases in bladder wet weight and Evans blue dye exuded, respectively, at doses of 75 microg/bladder), as confirmed by Gray's criteria. Pretreatment with mesna (2-mercaptoethanesulfonic acid), which interacts with acrolein resulting in an inactive compound, inhibited all changes induced by acrolein. Our results are the first demonstration that intravesical administration of acrolein induces hemorrhagic cystitis. This model of acrolein-induced hemorrhagic cystitis in mice may be an important tool for the evaluation of the mechanism by which acrolein induces bladder lesion, as well as for investigation of new uroprotective drugs.


Assuntos
Acroleína/toxicidade , Cistite/induzido quimicamente , Edema/induzido quimicamente , Hemorragia/induzido quimicamente , Bexiga Urinária/efeitos dos fármacos , Acroleína/administração & dosagem , Acroleína/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Mesna/farmacologia , Camundongos , Substâncias Protetoras/farmacologia
16.
Braz. j. med. biol. res ; 39(11): 1475-1481, Nov. 2006. graf, tab
Artigo em Inglês | LILACS | ID: lil-437822

RESUMO

Acrolein is a urinary metabolite of cyclophosphamide and ifosfamide, which has been reported to be the causative agent of hemorrhagic cystitis induced by these compounds. A direct cytotoxic effect of acrolein, however, has not yet been demonstrated. In the present study, the effects of intravesical injection of acrolein and mesna, the classical acrolein chemical inhibitor, were evaluated. Male Swiss mice weighing 25 to 35 g (N = 6 per group) received saline or acrolein (25, 75, 225 æg) intravesically 3, 6, 12, and 24 h before sacrifice for evaluation of bladder wet weight, macroscopic and histopathological changes by Gray's criteria, and 3 and 24 h for assessment of increase in vascular permeability. In other animals, mesna was administered intravesically (2 mg) or systemically (80 mg/kg) 1 h before acrolein. Intravesical administration of acrolein induced a dose- and time-dependent increase in vascular permeability and bladder wet weight (within 3 h: 2.2- and 21-fold increases in bladder wet weight and Evans blue dye exuded, respectively, at doses of 75 æg/bladder), as confirmed by Gray's criteria. Pretreatment with mesna (2-mercaptoethanesulfonic acid), which interacts with acrolein resulting in an inactive compound, inhibited all changes induced by acrolein. Our results are the first demonstration that intravesical administration of acrolein induces hemorrhagic cystitis. This model of acrolein-induced hemorrhagic cystitis in mice may be an important tool for the evaluation of the mechanism by which acrolein induces bladder lesion, as well as for investigation of new uroprotective drugs.


Assuntos
Animais , Masculino , Camundongos , Acroleína/toxicidade , Cistite/induzido quimicamente , Edema/induzido quimicamente , Hemorragia/induzido quimicamente , Bexiga Urinária/efeitos dos fármacos , Acroleína/administração & dosagem , Acroleína/antagonistas & inibidores , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mesna/farmacologia , Substâncias Protetoras/farmacologia
17.
SAR QSAR Environ Res ; 17(3): 311-21, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16815770

RESUMO

Over half of the failures in drug development are due to problems with the absorption, distribution, metabolism, excretion, and toxicity, or ADME/Tox properties of a candidate compound. The utilization of in silico tools to predict ADME/Tox and physicochemical properties holds great potential for reducing the attrition rate in drug research and development, as this technology can prioritize candidate compounds in the pharmaceutical R&D pipeline. However, a major concern surrounding the use of in silico ADME/Tox technology is the reliability of the property predictions. Bio-Rad Laboratories, Inc. has created a computational environment that addresses these concerns. This environment is referred to as KnowItAll. Within this platform are encoded a number of ADME/Tox predictors, the ability to validate these predictors with/without in-house data and models, as well as build a 'consensus' model that may be a much better model than any of the individual predictive model. The KnowItAll system can handle two types of predictions: real number and categorical classification.


Assuntos
Desenho de Fármacos , Modelos Biológicos , Modelos Químicos , Bases de Dados Factuais , Peso Molecular , Testes de Mutagenicidade , Redes Neurais de Computação , Farmacocinética , Ligação Proteica , Reprodutibilidade dos Testes , Solubilidade , Toxicologia
18.
Eur J Oral Sci ; 113(3): 210-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15953245

RESUMO

Oral mucositis is a frequent side-effect of cancer therapy. A definitive method of prophylaxis or treatment is not yet available. As pentoxifylline (PTX) and thalidomide (TLD) have been shown to inhibit cytokine synthesis, we studied the effects of these cytokine inhibitors in an experimental oral mucositis model. Oral mucositis was induced in Golden hamsters by the administration of 5-fluorouracil (5-FU) followed by mechanical trauma of the cheek pouch. On days 4, 5, 10, 12, 14 and 16, lesions induced by 5-FU were examined macroscopically and microscopically, and the presence and intensity of hyperemia, erythema, edema, inflammatory cell infiltration, hemorrhagic areas, ulcers and abscesses were recorded. Saline (control), PTX (5, 15, 45 mg kg(-1)) or TLD (10, 30, 90 mg kg(-1)) were administered daily and animals were killed on day 10 for macroscopic and histological analysis and assay of myeloperoxidase (MPO) activity. Animals were weighed daily, and total and differential leukocyte counts were performed on peripheral blood. PTX and TLD were found to reduce the macroscopic and histological parameters of oral mucositis and MPO activity. PTX and TLD also reversed peripheral neutrophilia, but only PTX prevented weight loss. The results indicate a protective effect of PTX and TLD, suggesting an important role for tumour necrosis factor-alpha (TNF-alpha) in the pathophysiology of 5-FU induced-oral mucositis in hamsters.


Assuntos
Imunossupressores/uso terapêutico , Pentoxifilina/uso terapêutico , Estomatite/prevenção & controle , Talidomida/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Abscesso/patologia , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Cricetinae , Modelos Animais de Doenças , Edema/patologia , Eritema/patologia , Fluoruracila/efeitos adversos , Hemorragia/patologia , Hiperemia/patologia , Contagem de Leucócitos , Masculino , Mesocricetus , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/lesões , Mucosa Bucal/patologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Úlceras Orais/patologia , Peroxidase/análise , Peroxidase/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Estomatite/induzido quimicamente , Estomatite/patologia , Fatores de Tempo
19.
Int J Tuberc Lung Dis ; 9(3): 276-81, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15786890

RESUMO

SETTING: Nine public health care centres in four Spanish cities. OBJECTIVE: To evaluate the efficacy and safety of 2 months of rifampicin (R) plus pyrazinamide (Z) therapy (2RZ) compared with a 6-month course of isoniazid therapy (6H) for treating latent tuberculosis infection (LTBI). DESIGN: Multicentered, randomised, comparative and prospective trial conducted in HIV-seronegative contacts of infectious pulmonary TB cases. RESULTS: Of 352 individuals, 199 received 6H and 153 2RZ; 73% of contacts receiving 6H and 71% receiving 2RZ completed treatment (P = 0.73). Treatment interruption due to hepatotoxicity (ALT/AST > 5 times upper limit of normal) was observed in 10% of contacts in the 2RZ group and in 2.5% of the 6H group (P = 0.007). This higher than expected rate of hepatotoxicity in the 2RZ arm led to premature termination of the study. Severe or fatal liver injury was not detected. Liver function tests normalised after discontinuation of treatment. We conclude that the use of RZ should only be considered when other regimens are unsuitable and intensive monitoring of liver function is feasible.


Assuntos
Antibióticos Antituberculose/uso terapêutico , Soronegatividade para HIV , Pirazinamida/uso terapêutico , Rifampina/uso terapêutico , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Antibióticos Antituberculose/administração & dosagem , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , HIV/imunologia , Anticorpos Anti-HIV/imunologia , Humanos , Lactente , Masculino , Estudos Prospectivos , Pirazinamida/administração & dosagem , Rifampina/administração & dosagem , Espanha , Resultado do Tratamento , Teste Tuberculínico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico
20.
J Ethnopharmacol ; 94(1): 59-65, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15261964

RESUMO

The activity of a crude ethanol extract of green propolis and its fractions obtained by partition with hexane, chloroform and n-butanol was assessed on luminol- and lucigenin- enhanced chemiluminescence (CL) produced by rabbit neutrophils (PMNs) stimulated with particles of serum-opsonized zymosan (OZ). The total production of reactive oxygen species (ROS) by PMNs was measured by the luminol-enhanced CL (LumCL) assay and the production of the superoxide anion (O2*-) by the lucigenin-enhanced CL (LucCL) assay. All evaluated propolis samples had inhibitory effect on the LumCL and LucCL, which was concentration dependent. The n-butanol and chloroform fractions displayed the highest inhibitory effect on the LumCL produced by PMNs stimulated with OZ, in comparison with both the ethanol extract and the hexane fraction. Besides, the hexane fraction was the one which presented the highest effect for the LucCL assay. Some isolated compounds from both n-butanol and chloroform fractions were also assessed, including kaempferide, isosakuranetin, aromadendrine-4'-methyl-ether and 3-prenyl-p-coumaric acid. Kaempferide presented the highest inhibitory effect on the LumCL in comparison with the other compounds. Moreover, under the conditions assessed, the studied green propolis samples and isolated compounds were not toxic to the rabbit PMNs.


Assuntos
Anti-Inflamatórios/farmacologia , Neutrófilos/efeitos dos fármacos , Própole/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Superóxidos/antagonistas & inibidores , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/toxicidade , Brasil , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Medições Luminescentes , Neutrófilos/metabolismo , Própole/química , Própole/toxicidade , Coelhos , Zimosan
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