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3.
J Intern Med ; 286(3): 268-289, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31282104

RESUMO

The host evolves redundant mechanisms to preserve physiological processing and homeostasis. These functions range from sensing internal and external threats, creating a memory of the insult and generating reflexes, which aim to resolve inflammation. Impairment in such functioning leads to chronic inflammatory diseases. By interacting through a common language of ligands and receptors, the immune and sensory nervous systems work in concert to accomplish such protective functions. Whilst this bidirectional communication helps to protect from danger, it can contribute to disease pathophysiology. Thus, the somatosensory nervous system is anatomically positioned within primary and secondary lymphoid tissues and mucosa to modulate immunity directly. Upstream of this interplay, neurons detect danger, which prompts the release of neuropeptides initiating (i) defensive reflexes (ranging from withdrawal response to coughing) and (ii) chemotaxis, adhesion and local infiltration of immune cells. The resulting outcome of such neuro-immune interplay is still ill-defined, but consensual findings start to emerge and support neuropeptides not only as blockers of TH 1-mediated immunity but also as drivers of TH 2 immune responses. However, the modalities detected by nociceptors revealed broader than mechanical pressure and temperature sensing and include signals as various as cytokines and pathogens to immunoglobulins and even microRNAs. Along these lines, we aggregated various dorsal root ganglion sensory neuron expression profiling datasets supporting such wide-ranging sensing capabilities to help identifying new danger detection modalities of these cells. Thus, revealing unexpected aspects of nociceptor neuron biology might prompt the identification of novel drivers of immunity, means to resolve inflammation and strategies to safeguard homeostasis.


Assuntos
Nociceptores/fisiologia , Sistema Nervoso Periférico/fisiologia , Células Receptoras Sensoriais/fisiologia , Citocinas/fisiologia , Hipersensibilidade a Drogas/imunologia , Exossomos/fisiologia , Proteína HMGB1/fisiologia , Humanos , Imunidade Inata/fisiologia , Imunoglobulinas/fisiologia , Infecções/imunologia , Mediadores da Inflamação/fisiologia , Neoplasias/fisiopatologia , Neuroimunomodulação/fisiologia , Nervos Periféricos/fisiologia , Tempo de Reação/fisiologia , Estresse Mecânico , Termorreceptores/fisiologia , Receptor 2 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Microambiente Tumoral/fisiologia
4.
PLoS One ; 12(4): e0175839, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28422994

RESUMO

The EU Directive 2010/63/EU changed the requirements regarding the use of laboratory animals and raised important issues related to assessing the severity of all procedures undertaken on laboratory animals. However, quantifiable parameters to assess severity are rare, and improved assessment strategies need to be developed. Hence, a Sheep Grimace Scale (SGS) was herein established by observing and interpreting sheep facial expressions as a consequence of pain and distress following unilateral tibia osteotomy. The animals were clinically investigated and scored five days before surgery and at 1, 3, 7, 10, 14 and 17 days afterwards. Additionally, cortisol levels in the saliva of the sheep were determined at the respective time points. For the SGS, video recording was performed, and pictures of the sheep were randomized and scored by blinded observers. Osteotomy in sheep resulted in an increased clinical severity score from days 1 to 17 post-surgery and elevated salivary cortisol levels one day post-surgery. An analysis of facial expressions revealed a significantly increased SGS on the day of surgery until day 3 post-surgery; this elevated level was sustained until day 17. Clinical severity and SGS scores correlated positively with a Pearson´s correlation coefficient of 0.47. Further investigations regarding the applicability of the SGS revealed a high inter-observer reliability with an intraclass correlation coefficient of 0.92 and an accuracy of 68.2%. In conclusion, the SGS represents a valuable approach for severity assessment that may help support and refine a widely used welfare assessment for sheep during experimental procedures, thereby meeting legislation requirements and minimizing the occurrence of unrecognized distress in animal experimentation.


Assuntos
Osteotomia , Medição da Dor/métodos , Dor/diagnóstico , Tíbia/cirurgia , Bem-Estar do Animal , Animais , Expressão Facial , Feminino , Hidrocortisona/análise , Hidrocortisona/metabolismo , Variações Dependentes do Observador , Dor/fisiopatologia , Dor/cirurgia , Período Pós-Operatório , Reprodutibilidade dos Testes , Saliva/química , Carneiro Doméstico , Tíbia/inervação , Gravação em Vídeo
5.
Am J Transplant ; 15(5): 1421-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25777324

RESUMO

Current immunosuppression in VCA is largely based on the experience in solid organ transplantation. It remains unclear if steroids can be reduced safely in VCA recipients. We report on five VCA recipients who were weaned off maintenance steroids after a median of 2 months (mean: 4.8 months, range 2-12 months). Patients were kept subsequently on a low dose, dual maintenance consisting of tacrolimus and mycophenolate mofetil/mycophenloic acid with a mean follow-up of 43.6 months (median = 40 months, range 34-64 months). Early and late acute rejections responded well to temporarily augmented maintenance, topical immunosuppression, and/or steroid bolus treatment. One late steroid-resistant acute rejection required treatment with thymoglobulin. All patients have been gradually weaned off steroids subsequent to the treatment of acute rejections. Low levels of tacrolimus (<5 ng/mL) appeared as a risk for acute rejections. Although further experience and a cautious approach are warranted, dual-steroid free maintenance immunosuppression appears feasible in a series of five VCA recipients.


Assuntos
Transplante de Face , Transplante de Mão , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Esteroides/uso terapêutico , Alotransplante de Tecidos Compostos Vascularizados , Adulto , Idoso , Soro Antilinfocitário/uso terapêutico , Feminino , Rejeição de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/análogos & derivados , Tacrolimo/administração & dosagem , Fatores de Tempo , Enxerto Vascular
6.
Behav Brain Res ; 241: 17-26, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23219968

RESUMO

While brain kinin B(1) receptor (B(1)R) is virtually absent in control rats, it contributes to hypertension via a midbrain dopaminergic (DA) mechanism in spontaneously hypertensive rat (SHR) and Angiotensin II (Ang II)-induced hypertension. This study aims at determining whether B(1)R can also affect stereotypic nocifensive behavior through DA and/or other neuromediators in the same models. The selective B(1)R agonist Sar[D-Phe(8)][des-Arg(9)]BK was injected i.c.v. (1 µg/site) to freely behaving SHR (16 weeks), Ang II-hypertensive rats (200 ng/kg/min × 2 weeks, s.c.) and control Wistar-Kyoto rats (WKY). Behavioral activity to the agonist was measured before and after treatment with receptor antagonists (10 µg/site i.c.v. or otherwise stated) for B(1) (SSR240612), tachykinin NK(1) (RP67580), glutamate NMDA (DL-AP5), DA D(1) (SCH23390, 0.2mg/kg s.c.) and D(2) (Raclopride, 0.16 mg/kg s.c.). Other studies included inhibitors (10 µg/site) of NOS (l-NNA) and iNOS (1400W). The possible desensitisation of B(1)R upon repeated intracerebral stimulation was also excluded. B(1)R expression was measured by qRT-PCR in selected areas and by immunohistochemistry in the ventral tegmental area. Results showed that the B(1)R agonist had no effect in WKY, yet it induced nocifensive behavioral manifestations in both models of hypertension (face washing, sniffing, head scratching, rearing, teeth chattering, grooming, digging, licking, wet-dog shakes). These responses were prevented by all antagonists and inhibitors tested, but 1400 W had a less inhibitory effect on most behaviors. Compared with WKY, B(1)R mRNA levels were markedly enhanced in hypothalamus, ventral tegmental area and nucleus accumbens of SHR and Ang II-treated rats. B(1)R was detected on DA neuron of the ventral tegmental area in SHR. Data suggest that kinin B(1)R is upregulated in midbrain DA system in hypertensive rats and its i.c.v. activation induced stereotypic nocifensive behavior that is mediated by several mediators, notably substance P, glutamate, DA and NO.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Receptor B1 da Bradicinina/agonistas , Comportamento Estereotipado/efeitos dos fármacos , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Benzazepinas/farmacologia , Antagonistas de Receptor B1 da Bradicinina , Encéfalo/metabolismo , Dioxóis/farmacologia , Antagonistas de Dopamina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Isoindóis/farmacologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Racloprida/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptor B1 da Bradicinina/genética , Receptor B1 da Bradicinina/metabolismo , Substância P/antagonistas & inibidores , Sulfonamidas/farmacologia
7.
J Evol Biol ; 25(7): 1438-47, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22686489

RESUMO

The major histocompatibility complex (MHC), which harbours the most polymorphic vertebrate genes, plays a critical role in the host-pathogen coevolutionary arms race. However, the extent to which MHC diversity determines disease susceptibility and long-term persistence of populations is currently under debate, as recent studies have demonstrated that low MHC variability does not necessarily hamper population viability. However, these studies typically assayed small and decimated populations in species with restricted distribution, thereby making inferences about the evolutionary potential of these populations difficult. Here, we show that MHC impoverishment has not constrained the ecological radiation and flourishing of falcons (Aves: Falconidae) worldwide. We found two remarkably different patterns of MHC variation within the genus Falco. Whereas MHC variation in kestrels (the basal group within the genus) is very high, falcons exhibit ancestrally low intra- and interspecific MHC variability. This pattern is not due to the inadvertent survey of paralogous genes or pseudogenes. Further, patterns of variation in mitochondrial or other nuclear genes do not indicate a generalized low level of genome-wide variability among falcons. Although a relative contribution of genetic drift cannot be completely ruled out, we propose the falcons went through an evolutionary transition, driven and maintained by natural selection, from primarily highly variable towards low polymorphic and slow-evolving MHC genes with a very specific immune function. This study highlights that the importance of MHC diversity cannot be generalized among vertebrates, and hints at the evolution of compensatory immune mechanisms in falcons to cope with emerging and continuously evolving pathogens.


Assuntos
Falconiformes/genética , Falconiformes/imunologia , Complexo Principal de Histocompatibilidade , Animais , Evolução Molecular , Falconiformes/classificação , Variação Genética , Pseudogenes , Seleção Genética
8.
Sarcoidosis Vasc Diffuse Lung Dis ; 29(1): 41-50, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23311122

RESUMO

BACKGROUND: Nocturnal desaturation may contribute to long-term pulmonary vascular stress in interstitial lung disease (ILD). We study the prevalence, severity and prognostic utility of nocturnal desaturation across ILD. METHODS: ILD patients with overnight oximetry (June 2006-August 2008) were reviewed (n = 134). Significant nocturnal desaturation was considered as > 10% of sleep with SpO2 < 90%. Desaturation index (DI) was defined as the number of desaturation events > 4%/hr. Covariates, including indices of nocturnal desaturation, were evaluated against mortality. RESULTS: Nocturnal desaturation was present in 49 (37%) patients. 31% of patients had pulmonary hypertension (PH) on echocardiography. Increased DI was associated with higher mortality independent of age, gender and BMI (HR 1.04; 95% CI 1.00, 1.06; p = 0.009). In separate models, DI and a) elevated brain natriuretic peptide (BNP; HR 1.04; 95% CI 1.00, 1.08; p = 0.04); b) moderate-severe PH on echocardiography (HR 3.15; 95% CI 1.24, 8.00; p = 0.02); and c) daytime resting SpO2 (HR 0.92; 95% CI 0.85, 0.99; p = 0.04) independently predicted mortality following adjustment for age, gender and BMI. CONCLUSION: Nocturnal desaturation is common and may be severe in ILD. Elevated nocturnal DI predicts higher mortality across ILD, independent of other vascular parameters. This finding may have important implications for the pathogenesis of PH in IPF.


Assuntos
Ritmo Circadiano , Hipertensão Pulmonar/epidemiologia , Hipóxia/epidemiologia , Doenças Pulmonares Intersticiais/epidemiologia , Oxigênio/sangue , Idoso , Biomarcadores/sangue , Ecocardiografia , Teste de Esforço , Feminino , Humanos , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/mortalidade , Hipóxia/sangue , Hipóxia/diagnóstico , Hipóxia/mortalidade , Londres/epidemiologia , Doenças Pulmonares Intersticiais/sangue , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Oximetria , Valor Preditivo dos Testes , Prevalência , Prognóstico , Modelos de Riscos Proporcionais , Testes de Função Respiratória , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Regulação para Cima
9.
Br J Pharmacol ; 154(5): 940-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18587442

RESUMO

BACKGROUND AND PURPOSE: Arsenicals have been used medicinally for decades to treat both infectious disease and cancer. Arsenic trioxide (As2O3) is effective for treatment of acute promyelocytic leukaemia (APL), yet the mechanism of action of this drug is still widely debated. Recently, As2O3 was shown to inhibit the activity of the selenoenzyme thioredoxin reductase (TrxR). TrxR has been proposed to be required for selenium metabolism. The effect of inhibitors of TrxR on selenium metabolism has yet to be assessed. This study aims to determine whether chemotherapeutics that target selenocysteine within selenoenzymes may also affect the metabolism of selenium. EXPERIMENTAL APPROACH: A lung cell line, A549, was used to assess the effect of TrxR inhibitors on selenium metabolism, using 75Se-selenite. The level of mRNA encoding cytosolic TrxR (TrxR1) was determined using real-time reverse transcriptase-PCR. TrxR activity was determined in whole-cell extracts. KEY RESULTS: Exposure of cells to As2O3, arsenite or auranofin led to a concentration-dependent reduction of selenium metabolism into selenoproteins. Knockdown of TrxR1, using small inhibitory RNA, did not affect selenium metabolism. Exposure of cells to monomethylarsonic acid, a potent inhibitor of TrxR, did not alter selenium metabolism but did inhibit enzyme activity. CONCLUSIONS AND IMPLICATIONS: As2O3 and auranofin block the metabolism of selenium in A549 cells. Because As2O3 is used to treat APL, our findings may reveal the mechanism of this therapeutic action and lead to further research targeting selenium metabolism to find novel chemotherapeutic agents for the treatment of APL.


Assuntos
Adenocarcinoma/metabolismo , Antineoplásicos/farmacologia , Arsenicais/farmacologia , Auranofina/farmacologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Óxidos/farmacologia , Selenoproteínas/biossíntese , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Trióxido de Arsênio , Arsenitos/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Humanos , Leucemia Promielocítica Aguda/enzimologia , Leucemia Promielocítica Aguda/metabolismo , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Biossíntese de Proteínas/efeitos dos fármacos , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Radioisótopos de Selênio , Compostos de Sódio/farmacologia , Selenito de Sódio/metabolismo , Tiorredoxina Redutase 1/antagonistas & inibidores , Tiorredoxina Redutase 1/metabolismo
11.
Br J Pharmacol ; 154(1): 136-43, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18311190

RESUMO

BACKGROUND AND PURPOSE: We investigated whether or not kinin receptors play a role in diabetic blood-retinal barrier breakdown, which is a leading cause of vision loss. EXPERIMENTAL APPROACH: Blood-retinal barrier breakdown was quantified using Evans blue, and expression of kinin B(1) receptor mRNA was measured using quantitative reverse transcrition-PCR. Diabetic rats (streptozotocin (STZ), 65 mg kg(-1)) received a single intraocular injection of bradykinin (BK) or des-Arg(9)-BK, alone, or in combination with antagonists for B(1) (des-Arg(10)-Hoe140, R-715) and/or B(2) (Hoe140) receptors, given intraocularly or intravenously (i.v.). KEY RESULTS: In control rats, BK (0.1-10 nmol) dose-dependently increased plasma extravasation, which was inhibited by Hoe140 (0.2 nmol), whereas des-Arg(9)-BK (0.1 and 1 nmol) was without effect. B(1) receptor mRNA was markedly increased in retinas of diabetic rats, and this was prevented by N-acetyl-L-cysteine (1 g kg(-1) day(-1) for 7 days). Plasma extravasation in retinas of STZ-diabetic rats was higher than in controls and enhanced by des-Arg(9)-BK. Response to des-Arg(9)-BK was inhibited by intraocular or i.v. injection of B(1) receptor antagonists. Diabetes-induced plasma extravasation was inhibited only by a combination of des-Arg(10)-Hoe140 and Hoe 140 (100 nmol kg(-1), i.v. 15 min earlier) or by R-715 (1 micromol kg(-1), i.v.) injected daily for 7 days. CONCLUSIONS AND IMPLICATIONS: Kinin B(1) receptors are upregulated in retinas of STZ-diabetic rats through a mechanism involving oxidative stress. Both kinin B(1) and B(2) receptors contribute to increased plasma extravasation in diabetic retinopathy. Chronic inhibition of both kinin receptors, possibly with antioxidant adjuvants, may be a novel therapeutic strategy for diabetic retinopathy.


Assuntos
Barreira Hematorretiniana/fisiologia , Diabetes Mellitus Experimental/metabolismo , Receptor B1 da Bradicinina/metabolismo , Receptor B2 da Bradicinina/metabolismo , Retina/metabolismo , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Benzotiazóis , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Diaminas , Relação Dose-Resposta a Droga , Edema/patologia , Azul Evans , Masculino , Compostos Orgânicos , Estresse Oxidativo/efeitos dos fármacos , Plasma/metabolismo , Quinolinas , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
J Drug Target ; 12(6): 363-72, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15545086

RESUMO

Morpholino phosphorodiamidate (MO) DNA mimics display excellent water solubility and hybridization properties toward DNA and RNA, and have been utilized in the model vertebrate zebrafish (Danio rerio) for genome-wide, sequence-based, reverse genetic screens during embryonic development. Peptide nucleic acids (PNAs) exhibit excellent mismatch discrimination, nuclease resistance, and protease resistance, but low solubility. Negatively charged DNA mimics composed of alternating residues of trans-4-hydroxy-L-proline peptide nucleic acid monomers and phosphono peptide nucleic acid monomers (HypNA-pPNA) combine all of the positive features of both MOs and PNAs. Thus, we evaluated PNA oligomers and HypNA-pPNA oligomers as an alternative to MOs for oligonucleotide inhibition of gene expression in zebrafish embryos. We observed that HypNA-pPNA 18-mers displayed comparable potency to MO 25-mers as knockdown agents against chordin, notail and uroD, with greater mismatch stringency. Furthermore, we observed that a specific HypNA-pPNA 18-mer elicited the dharma (bozozok)(-/-) phenotype in zebrafish embryos, which MO 25-mers do not. These observations validate HypNA-pPNAs as an alternative to MO oligomers for reverse genetic studies. The stronger hybridization and greater specificity of HypNA-pPNAs enable knockdown of mRNAs unaffected by MO oligomers.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Hidroxiprolina/química , Oligorribonucleotídeos Antissenso/farmacologia , Organofosfonatos/química , Ácidos Nucleicos Peptídicos/química , RNA Mensageiro/antagonistas & inibidores , Peixe-Zebra/embriologia , Animais , Sequência de Bases , Embrião não Mamífero/metabolismo , Mimetismo Molecular , Oligorribonucleotídeos Antissenso/química , RNA Mensageiro/biossíntese
13.
J Virol ; 75(4): 1864-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11160685

RESUMO

We have previously examined the transcription and splicing of open reading frames (ORFS) 71 (K13), 72, and 73 of Kaposi's sarcoma-associated herpesvirus (KSHV) in the primary effusion lymphoma cell line BCP-1 (latently infected with KSHV) (45). The three genes encoded by these ORFs (for vFLIP, vCyclin, and latency-associated nuclear antigen [LANA]) are transcribed from a common transcription start site in BCP-1 cells during both latency and the lytic cycles. The resulting transcript is spliced to yield a 5.32-kb message encoding LANA, vCyclin, and vFLIP and a 1.7-kb bicistronic message encoding vCyclin and vFLIP. To investigate whether the vFLIP protein could be expressed from this vCyclin/vFLIP message, we utilized a bicistronic luciferase reporter system. The genes for Renilla and firefly luciferases (which utilize different substrates) were cloned in tandem downstream from a T7 RNA polymerase promoter. Fragments of DNA immediately upstream from the initiating codon of vFLIP were cloned between the two luciferase genes. The relative expression of the two luciferases, one directed by the putative internal ribosome entry site (IRES) sequences and the other by cap-dependent ribosome scanning, was used to compare the activities of the different DNA fragments. A minimum fragment of 233 bp within the coding region of vCyclin was found to direct efficient expression of the downstream cistron (firefly luciferase). The activity of this IRES was orientation dependent and unaffected by methods used to inhibit cap-dependent translation. This is the first demonstration of an IRES element encoded by a DNA virus and may represent a novel mechanism through which KSHV controls protein expression.


Assuntos
Ciclinas/genética , Herpesvirus Humano 8/genética , Fases de Leitura Aberta , RNA Viral/genética , Ribossomos/química , Ribossomos/metabolismo , Sequência de Bases , Linhagem Celular , Ciclinas/metabolismo , Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/fisiologia , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Biossíntese de Proteínas , RNA Viral/química , Ribossomos/genética , Transcrição Gênica , Transfecção , Proteínas Virais
14.
Evolution ; 55(10): 2105-15, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11761069

RESUMO

Genetic markers that differ in mode of inheritance and rate of evolution (a sex-linked Z-specific microsatellite locus, five biparentally inherited microsatellite loci, and maternally inherited mitochondrial [mtDNA] sequences) were used to evaluate the degree of spatial genetic structuring at macro- and microgeographic scales, among breeding regions and local nesting populations within each region, respectively, for a migratory sea duck species, the spectacled eider (Somateria fisheri). Disjunct and declining breeding populations coupled with sex-specific differences in seasonal migratory patterns and life history provide a series of hypotheses regarding rates and directionality of gene flow among breeding populations from the Indigirka River Delta, Russia, and the North Slope and Yukon-Kuskokwim Delta, Alaska. The degree of differentiation in mtDNA haplotype frequency among breeding regions and populations within regions was high (phiCT = 0.189, P < 0.01; phiSC = 0.059, P < 0.01, respectively). Eleven of 17 mtDNA haplotypes were restricted to a single breeding region. Genetic differences among regions were considerably lower for nuclear DNA loci (sex-linked: phiST = 0.001, P > 0.05; biparentally inherited microsatellites: mean theta = 0.001, P > 0.05) than was observed for mtDNA. Using models explicitly designed for uniparental and biparentally inherited genes, estimates of spatial divergence based on nuclear and mtDNA data together with elements of the species' breeding ecology were used to estimate effective population size and degree of male and female gene flow. Differences in the magnitude and spatial patterns of gene correlations for maternally inherited and nuclear genes revealed that females exhibit greater natal philopatry than do males. Estimates of generational female and male rates of gene flow among breeding regions differed markedly (3.67 x 10(-4) and 1.28 x 10(-2), respectively). Effective population size for mtDNA was estimated to be at least three times lower than that for biparental genes (30,671 and 101,528, respectively). Large disparities in population sizes among breeding areas greatly reduces the proportion of total genetic variance captured by dispersal, which may accelerate rates of inbreeding (i.e., promote higher coancestries) within populations due to nonrandom pairing of males with females from the same breeding population.


Assuntos
Aves/genética , Marcadores Genéticos , Variação Genética , Animais , Regiões Árticas , Sequência de Bases , Aves/classificação , Primers do DNA , DNA Mitocondrial/genética , Feminino , Masculino , Oviposição , Filogenia , Caracteres Sexuais
16.
Ann Oncol ; 10(8): 907-14, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10509151

RESUMO

BACKGROUND: To define a maximum tolerated dose (MTD) for the combination of epirubicin and cyclophosphamide with filgrastim (r-met-HuG-CSF) in patients with advanced solid tumors and non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Thirty-five patients with advanced solid tumors were enrolled in stages I and II. Twenty-one patients were treated in stage I in sequential cohorts of at least three patients at increasing dosage levels of cyclophosphamide and epirubicin, for up to six cycles every 21 days. At the completion of stage I, a MTD for epirubicin was established. Fourteen patients were treated in stage II, in cohorts of three or more. The epirubicin dose remained constant at the MTD dosage from stage I. Cyclophosphamide was further dose-escalated to establish its MTD. Twenty-one patients with previously untreated non-Hodgkin's lymphoma were treated in stage III with the MTD established in the prior stages. RESULTS: The MTD in stage I was epirubicin 150 mg/m2 and cyclophosphamide 1500 mg/m2 with cumulative neutropenia as the dose-limiting toxicity (DLT). Cumulative thrombocytopenia prevented further dose-escalation of cyclophosphamide in stage II. The stage III regimen consisted of six, 21-day cycles of epirubicin 150 mg/m2, cyclophosphamide 1500 mg/m2, vincristine 2 mg, and prednisolone 100 mg for five days with filgrastim support. Nineteen of twenty-one patients (90%) completed six cycles of treatment, eight (38%) without dose reduction. Common toxicity criteria (CTC) grade 4 neutropenia (neutrophil nadir < 0.5 x 10(9)/l) was documented in 85 of 118 cycles (72%). Neutropenic fever was documented in 17 of 21 patients (81%) on at least one occasion. Severe thrombocytopenia (< 25 x 10(9)/l) was seen in fourteen of 118 cycles (12%) and increased with cycle number. There was no significant non-hematological toxicity. CONCLUSION: Significant dose-escalation of epirubicin and cyclophosphamide was possible with filgrastim support. The MTD achieved was approximately double that of standard-dose therapy. This study forms the basis of an ongoing randomized study evaluating dose-intensification in intermediate grade NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Linfoma não Hodgkin/tratamento farmacológico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Austrália , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Epirubicina/administração & dosagem , Feminino , Filgrastim , Seguimentos , Humanos , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Proteínas Recombinantes , Taxa de Sobrevida , Resultado do Tratamento
17.
J Virol ; 73(6): 5149-55, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10233979

RESUMO

Human herpesvirus 8 (HHV-8; also designated Kaposi's sarcoma-associated herpesvirus) is the likely etiological agent of Kaposi's sarcoma (KS). HHV-8 encodes a latent nuclear antigen (LNA) which is the product of the viral gene orf 73. LNA is recognized by most infected patient sera and is the basis of current immunofluorescence assays used in epidemiological studies of HHV-8 infection. Here we describe the characterization of four monoclonal antibodies raised to the C-terminal third of LNA-glutathione S-transferase fusion proteins. These monoclonal antibodies recognized discrete linear epitopes within the C terminus and repetitive region of LNA, detected antigen in primary effusion lymphoma (PEL) cells, and precipitated a 220- to 230-kDa protein doublet corresponding to LNA from HHV-8-infected PEL cell lines. In situ immunocytochemistry of KS lesions with these antibodies show that LNA is extensively expressed in KS spindle cells.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/análise , Herpesvirus Humano 8/imunologia , Antígenos Virais/fisiologia , Linhagem Celular , Mapeamento de Epitopos , Imunofluorescência , Humanos , Testes de Precipitina , Sarcoma de Kaposi/virologia
18.
Virology ; 257(1): 84-94, 1999 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10208923

RESUMO

We examined the transcription and splicing of open reading frames (ORFs) 71 (K13)-74 of human herpesvirus-8 (HHV-8) in the primary effusion lymphoma cell line BCP-1 (latently infected with HHV-8), using a combination of NORTHERN blot analysis, RT-PCR, and rapid amplification of cDNA ends (PCR-RACE). The three genes encoded by ORFs 71, 72, and 73 [viral FLICE inhibitory protein (v-FLIP), v-cyclin, latent nuclear antigen (LNA)] are transcribed from a common transcription start site in BCP-1 cells uninduced (latent) or induced (lytic) with n-butyrate. The resulting transcript is spliced to yield a 5.32-kb message encoding LNA, v-cyclin, and v-FLIP and a 1.7-kb bicistronic message encoding v-cyclin and v-FLIP. The two genes encoded by ORFs K14 and 74 (v-Ox2 and v-GPCR) are transcribed as a 2.7-kb bicistronic transcript that is induced with n-butyrate. A small (149-bp) intron is spliced from the intragenic noncoding region immediately before the v-GPCR initiating codon. Examination of sequence elements in the promoter of the LNA/v-cyclin/v-FLIP operon revealed TAATGARAT and Octamer binding motifs characteristic of herpesvirus immediate-early genes. Sequence elements in the v-Ox2/v-GPCR promoter included AP1 and Zta-like (EBV Zebra transactivator) binding motifs consistent with the n-butyrate induction of this operon.


Assuntos
Herpesvirus Humano 8/genética , Peptídeos e Proteínas de Sinalização Intracelular , Linfoma/virologia , Fases de Leitura Aberta , Fosfoproteínas , Transcrição Gênica , Sequência de Bases , Northern Blotting , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Proteínas de Transporte/genética , Mapeamento Cromossômico , Ciclinas/genética , Humanos , Linfoma/genética , Dados de Sequência Molecular , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Células Tumorais Cultivadas , Proteínas Virais
20.
Pharm World Sci ; 20(5): 206-13, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9820883

RESUMO

Bisphosphonates are a class of drugs which are strongly attracted to the bone where they influence the calcium metabolism, mainly by inhibition of the osteoclast-mediated bone resorption. This property makes these compounds suited for the treatment of several diseases of the bone. In Paget's disease, several bisphosphonates can reduce bone pain and decrease the bone turnover 60-70%. Cyclical oral etidronate and daily oral alendronate both proved to reduce the vertebral fracture rate for postmenopausal osteoporotic woman, while most investigated bisphosphonates can increase spinal bone mass in osteoporosis. Bisphosphonates can help lowering serum calcium and reverse skeletal complications in malignancy mediated bone diseases. Oral and intravenous administration of therapeutic doses is relatively safe. In general, gastrointestinal disturbances are described most often and the oldest, least potent, bisphosphonate etidronate can induce osteomalacia. The various characteristics of bisphosphonates: physicochemical, biological, therapeutic and toxicological, vary greatly depending on the structure of the individual bisphosphonate. Even small changes in the structure can lead to enormous differences in potency. Overall, this class of drugs offers several prospects for the future.


Assuntos
Doenças Ósseas/tratamento farmacológico , Difosfonatos/uso terapêutico , Doenças Ósseas/metabolismo , Difosfonatos/farmacocinética , Feminino , Humanos , Relação Estrutura-Atividade
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