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1.
Toxicol Pathol ; 43(5): 730-2, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25530274

RESUMO

The International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice proposal (INHAND) has been operational since 2005. A Global Editorial Steering Committee manages the overall objectives of the project, and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups, drawing upon experts from North America, Europe, and Japan. Great progress has been made with 9 systems published to date--respiratory, hepatobiliary, urinary, central/peripheral nervous systems, male reproductive and mammary, zymbals, clitoral, and preputial glands in Toxicologic Pathology and the integument and soft tissue and female reproductive in the Journal of Toxicologic Pathology as supplements and on a Web site--www.goReni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photomicrographs of morphologic changes, information regarding pathogenesis, and key references. The purpose of this brief communication is to provide an update on the progress of INHAND.


Assuntos
Pesquisa Biomédica/normas , Guias como Assunto , Patologia/normas , Terminologia como Assunto , Toxicologia/normas , Animais , Camundongos , Ratos , Projetos de Pesquisa
2.
Exp Toxicol Pathol ; 65(6): 875-82, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23332645

RESUMO

The study presented was conducted following the reproductive study guideline OECD Guideline 416 Two-Generation Reproduction Toxicity Study. Sprague-Dawley rats were exposed to 2000, 10,000 and 50,000 ppm of HFC-245fa. There was an unexpected mortality of lactating dams in the medium and high dose group beginning at day 10 of lactation. Statistically significant histopathological alterations were observed in the cerebellum of a total of 9/30 females of the high dose group of the F0-generation and in 10/27 females of the high dose group of the F1-generation. In contrast there were no brain lesions found in males or non-pregnant females of all dose groups. Neuronal necrosis and degeneration in the cerebellar cortex were observed as the most severe finding. Furthermore vacuolation of the neuropil in different degrees was diagnosed in 7/30 females of the F0-generation and in 9/30 females of the F1-generation. Acute hemorrhages - in particular perivascular - occurred in 5/30 females of the F0- and in 5/30 females of the F1-generation indicating a disturbed vascular integrity. The main lesions found in the cerebrum were glial scars in the corpus callosum and restricted to 2/30 females of the F0-generation of the high dose group. The increased incidence of myocardial fibrosis and mononuclear cell infiltration in males - indicating myocarditis - was only seen in the F0-generation of the high dose group. Females of the F1-generation of the high dose group showed an increased incidence of minimal myocardial fibrosis. In summary, histopathology revealed that the brain, particularly the cerebellum, and to a minor degree the heart turned out to be the toxicological target organs of the substance. Presumably substance-related energy deprivation may be responsible for the observed changes. One of the metabolites, 3,3,3-trifluoropropanoic acid has been shown to be capable of causing this effect.


Assuntos
Poluentes Atmosféricos/toxicidade , Encéfalo/efeitos dos fármacos , Hidrocarbonetos Fluorados/toxicidade , Exposição por Inalação/efeitos adversos , Lactação , Exposição Materna/efeitos adversos , Poluentes Atmosféricos/farmacocinética , Animais , Encéfalo/patologia , Cerebelo/efeitos dos fármacos , Cerebelo/crescimento & desenvolvimento , Cerebelo/patologia , Cérebro/efeitos dos fármacos , Cérebro/crescimento & desenvolvimento , Cérebro/patologia , Relação Dose-Resposta a Droga , Feminino , Coração/efeitos dos fármacos , Coração/crescimento & desenvolvimento , Hidrocarbonetos Fluorados/farmacocinética , Lactação/metabolismo , Miocárdio/patologia , Necrose , Gravidez , Ratos , Ratos Sprague-Dawley , Análise de Sobrevida , Testes de Toxicidade
3.
Neuroscience ; 144(1): 135-43, 2007 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-17049171

RESUMO

Acetylcholine receptor (AChR) supramolecular aggregates that have hitherto only been accessible to examination by electron microscopy were imaged with stimulated emission depletion (STED) fluorescence microscopy, providing resolution beyond limits of diffraction of classical wide-field or confocal microscopes. We examined a Chinese hamster ovary cell liner CHO-K1/A5, that stably expresses adult murine AChR. Whereas confocal microscopy displays AChR clusters as diffraction-limited dots of approximately 200 nm diameter, STED microscopy yields nanoclusters with a peak size distribution of approximately 55 nm. Utilizing this resolution, we show that cholesterol depletion by acute (30 min, 37 degrees C) exposure to methyl-beta-cyclodextrin alters the short and long range organization of AChR nanoclusters on the cell surface. In the short range, AChRs form larger nanoclusters, possibly related to the alteration of cholesterol-dependent protein-protein associations. Ripley's K-test on STED images reveals changes in nanocluster distribution on larger scales (0.5-3.5 microm), which possibly are related to the abolition of cytoskeletal physical barriers preventing the lateral diffusion of AChR nanoclusters.


Assuntos
Receptores Nicotínicos/fisiologia , Receptores Nicotínicos/ultraestrutura , Algoritmos , Animais , Células CHO , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Colesterol/fisiologia , Cricetinae , Cricetulus , Interpretação Estatística de Dados , Corantes Fluorescentes , Processamento de Imagem Assistida por Computador , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Receptores de Superfície Celular/fisiologia , Receptores de Superfície Celular/ultraestrutura
4.
Oncogene ; 25(6): 813-26, 2006 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-16205639

RESUMO

The terminal ends of eukaryotic chromosomes, termed telomeres, progressively shorten during each round of cell division eventually leading cells into senescence. Tumor cells typically overcome this barrier to unlimited proliferation by activation of the human telomerase reverse transcriptase (hTERT) gene. In contrast, in most human somatic cells hTERT expression is tightly repressed by multiple tumor suppressors. Here, we studied the regulation of hTERT by the p53 family member p73. We show that forced expression of p73 or activation of endogenous p73 by E2F1 results in the downregulation of telomerase activity. Vice versa, siRNA-mediated knockdown of p73 induces hTERT expression. Responsiveness to p73 is conferred by Sp1 binding sites within the hTERT core promoter. In tumor cells, p73 isoforms lacking the transactivation domain (DeltaNp73) are frequently overexpressed and believed to function as oncogenes. We show that DeltaNp73 antagonizes the repressive effect of the proapoptotic p53 family members on hTERT expression and, in addition, induces hTERT expression in telomerase-negative cells by interfering with E2F-RB-mediated repression of the hTERT core promoter. These data provide evidence that the p73 gene functions as an important regulator of telomerase activity with implications for embryonic development, cellular differentiation and tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Telomerase/genética , Telomerase/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/fisiologia , Sítios de Ligação , Células Cultivadas , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Regulação Enzimológica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , RNA Interferente Pequeno , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica , Ativação Transcricional , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor
5.
Electrophoresis ; 22(9): 1801-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11425235

RESUMO

Renal cell carcinoma (RCC) represent approximately 5% of all cancer deaths. At the time of presentation, over 50% of the patients have already developed locally advanced or metastatic disease with five-year survival rates of less than 20%. Although relative resistant to conventional regimens, RCC are partially susceptible to T cell-based immunotherapy. To further develop this treatment modality, two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was applied for both the mapping of the key components of the major histocompatibility complex (MHC) class I antigen processing and presentation machinery (APM) and the characterization of the constitutive and cytokine-regulated protein expression profiles in a representative human RCC cell line. The latter aspect is based on the fact, that the expression level of some of the APM components can be altered in response to interferon (IFN)-gamma treatment. Total cell lysates from untreated and IFN-gamma-treated tumor cells were separated on 2-D PAGE gels using broad range immobilized pH gradient (IPG) strips. Serial Western blot analyses using sets of APM-specific antibodies were performed to target the relevant protein spots. Protein verification was mostly accomplished via peptide mass finger-printing using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). To date, the majority of the APM-related components have been identified and mapped. In addition, the different protein expression profiles of untreated and IFN-gamma-treated RCC cells are under investigation.


Assuntos
Carcinoma de Células Renais/imunologia , Antígenos de Histocompatibilidade Classe I/análise , Neoplasias Renais/imunologia , Apresentação de Antígeno , Eletroforese em Gel Bidimensional , Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Mapeamento de Peptídeos , Células Tumorais Cultivadas
6.
Orv Hetil ; 142(7): 341-4, 2001 Feb 18.
Artigo em Húngaro | MEDLINE | ID: mdl-11243016

RESUMO

The authors report the first data having applied the indirect genomic diagnosis in carrier screening in Hungary. 22 patients with haemophilia B and female family members of 14 out of them were examined by PCR based restriction fragment length polymorphism analysis. The combined use of 3 intra- and 1 extragenic polymorphisms have been examined at the same population. DNA fragments, containing the single nucleotide change polymorphic site (Xmnl, Hhal, Taql), or the 50 bp insertion/deletion element (Dde) were amplified. The products were digested by the appropriate restriction digestion enzyme and were detected on agarose gel following ethidium-bromide staining. 20 siblings were interested in the determination of their carrier-state. 15 (75%) of them could get definite diagnosis. The carrier-state was established in 7 cases, excluded in 8 subjects. For the remaining 5 participants studied, the absence of the parental DNA sample caused uncertainty, while in 2 cases (10%) none of the analyzed RFLP was informative. The heterozygosity rate, the gene and haplotype frequency were also recorded and compared with the international data. The indirect methods have proved to be sufficient and well suitable for routine carrier testing. The results provide the basis of the subsequent prenatal diagnosis.


Assuntos
Testes Genéticos/métodos , Genoma Humano , Hemofilia B/diagnóstico , Hemofilia B/genética , Heterozigoto , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
7.
J Insect Physiol ; 47(6): 563-571, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11249944

RESUMO

A new hypertrehalosaemic peptide (Tea-HrTH; pQLNFSTGWGG-NH(2)) was isolated from the corpora cardiaca (CC) of the sawfly Tenthredo arcuata. The hypertrehalosaemic peptides found in the CC of five Bombus species and the paper wasp Polistes fuscata were identical to the adipokinetic hormone II of the desert locust, Schistocerca gregaria (Scg-AKH-II). The hypertrehalosaemic peptides found in the yellowjacket Vespula vulgaris and the hornet Vespa crabro were identical to the adipokinetic hormone of the cricket, Gryllus bimaculatus (Grb-AKH).All species examined had a large storage crop which, when filled with honey, held up to one-third of their total body weight. Overwintering queens of P. fuscata had large stores of carbohydrates and lipids in the abdomen, and were able to survive months of fasting. Workers of Bombus hortorum (bumble-bee), Apis mellifera (honey-bee) and V. vulgaris had little or no fat body. These species could fly as long as sugar was present in their crops, but they stopped flying as the carbohydrates in the crop disappeared. There was no significant increase in the haemolymph carbohydrate titres after injections of CC extracts or corresponding synthetic peptides into workers of B. hortorum or into males and females of T. arcuata. There was a moderate increase in haemolymph carbohydrate titres when these peptides were injected into overwintering queens of P. fuscata and into workers of V. crabro, both with significant amounts of fat body. However, well-fed V. vulgaris workers, with very little fat body, also responded to their own hypertrehalosaemic peptide.

8.
J Insect Physiol ; 47(4-5): 475-83, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11166312

RESUMO

Biosynthesis of the unique defensive compound pederin is confined to female rove beetles of the genus Paederus (Coleoptera: Staphylinidae). These (+)-females endow their eggs with toxin whereas (-)-females, which occur both naturally and in laboratory reared specimens, do not. The latter are aposymbionts lacking biosynthetic capabilities because of endosymbiotic deficiency. They can, however, be induced to accumulate pederin if fed with (+)-eggs during larval development. The endosymbionts can thus be transmitted by ingestion of (+)-Eggs. (+)-eggs treated with benzylpenicillin, erythromycin, oxytetracycline or streptomycin show that the induction of pederin accumulation depends on the antibiotic's spectrum of efficaciousness, its dosage and duration of the treatment. Certain bacteria, probably belonging to the gram-negative type, must be transmitted to produce (+)-females.

9.
Acta Biol Hung ; 51(2-4): 369-77, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11034162

RESUMO

The biological potencies of a number of naturally-occurring octa- and decapeptides of the large AKH/RPCH family of peptides were determined in Locusta migratoria using the lipid-mobilising assay in vivo and the acetate uptake assay in vitro. The most potent of the newly-tested peptides in the in vitro assay, Phl-CC, differs from the endogenous major locust peptide, Lom-AKH-I, only by an exchange of serine versus threonine at position 10. However, the most active peptide in the in vitro assay remains Lom-AKH-III. At the other extreme is the peptide Mem-CC which contains a tyrosine residue at position 4 rather than the more typical phenylalanine. This peptide is over 20,000 times less potent than Lom-AKH-III in the in vitro assay, and also results in an unusual dose-response curve in the in vivo assay. Only a few peptides are approximately equipotent in both assays, but mostly the bioanalogues have a higher potency in vitro. The majority of them are 2- to 10-fold more potent in vitro, but Ani-AKH and Lom-AKH-III are 19- and 48-fold more potent. The results are discussed in relation to either the actions of proteases or of possible preferential binding of different receptors involved in the different assays.


Assuntos
Gafanhotos/efeitos dos fármacos , Hormônios de Inseto/farmacologia , Oligopeptídeos/farmacologia , Ácido Acético/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Feminino , Gafanhotos/metabolismo , Técnicas In Vitro , Hormônios de Inseto/química , Metabolismo dos Lipídeos , Oligopeptídeos/química , Ácido Pirrolidonocarboxílico/análogos & derivados
10.
Insect Biochem Mol Biol ; 30(11): 1061-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10989293

RESUMO

The corpora cardiaca of the African pyrgomorphid grasshoppers Phymateus morbillosus and Dictyophorus spumans contain three adipokinetic hormones (AKHs): besides two already known AKHs, Phm-AKH-I and Scg-AKH-II (Gäde et al., 1996 [Gäde, G., Kellner, R., Rinehart, K.L., 1996. Pyrgomorphid grasshoppers of the genus Phymateus contain species-specific decapeptides of the AKH/RPCH family regulating lipid-mobilisation during flight. Physiol. Entomol. 21, 193-202]), a new AKH-III, denoted Phm-AKH-III, pGlu-Ile-Asn-Phe-Thr-Pro-Trp-Trp-NH(2), has been characterised. This is only the second AKH-III identified so far, thus, only three insect species - all of them grasshoppers - contain three active AKHs. Phm-AKH-III differs from Lom-AKH-III from the migratory locust, Locusta migratoria, only in position 2: isoleucine is present instead of leucine. The structure of the Phm-AKH-III was confirmed by synthesis, subsequent mass determination and reversed-phase high-performance liquid chromatography. The synthetic peptide also induced hyperlipaemia in D. spumans and L. migratoria.


Assuntos
Gafanhotos/enzimologia , Hormônios de Inseto/metabolismo , Metabolismo dos Lipídeos , Locomoção/fisiologia , Oligopeptídeos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Hormônios de Inseto/síntese química , Hormônios de Inseto/isolamento & purificação , Oligopeptídeos/síntese química , Oligopeptídeos/isolamento & purificação , Ácido Pirrolidonocarboxílico/análogos & derivados
11.
Eur J Biochem ; 267(17): 5502-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10951209

RESUMO

A structurally unusual member of the adipokinetic hormone/red pigment-concentrating hormone peptide family was isolated from corpora cardiaca of the painted lady butterfly, Vanessa cardui. Its primary structure was assigned by Edman degradation and nano-electrospray-time-of-flight mass spectrometry as pQLTFTSSWGGK (Vac-AKH). Vac-AKH represents the first 11mer and the first nonamidated peptide in this family. The peptide shows significant adipokinetic activity in adult specimens of V. cardui. Injection of 10 pmol of synthetic Vac-AKH into 4-day-old decapitated males resulted in an approximately 150% increase of hemolymph lipids after 90 min. Half maximal adipokinetic activity was achieved with about 0. 1 pmol of Vac-AKH. During a 2-h incubation of corpora cardiaca/corpora allata complexes in medium containing 50 mM KCl, significant amounts of Vac-AKH were released from the glands.


Assuntos
Hormônios de Inseto/química , Hormônios de Inseto/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Sequência de Aminoácidos , Animais , Borboletas , Cromatografia Líquida de Alta Pressão , Hormônios de Inseto/isolamento & purificação , Metabolismo dos Lipídeos , Masculino , Espectrometria de Massas/métodos , Oligopeptídeos/isolamento & purificação , Ácido Pirrolidonocarboxílico/análogos & derivados , Espectrofotometria Ultravioleta
12.
Biochem J ; 349(Pt 2): 455-61, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10880344

RESUMO

In contrast to neutrophils or B-lymphocytes, cells of the monocytic lineage like rat macrophages, human peripheral blood monocytes and Mono Mac 6 cells contain a strong inhibitor of 5-lipoxygenase (5-LO) activity, which scavenges hydroperoxides and inhibits 5-LO activity in broken-cell preparations in the absence of exogenously added thiols. Chromatographic purification of the inhibitor from the human monocytic cell line Mono Mac 6 and amino acid sequence analysis revealed that the inhibitory factor is glutathione peroxidase-1 (GPx-1). In contrast to the peroxidase activity of GPx-1, 5-LO inhibition by GPx-1 was supported by beta-mercaptoethanol and there was no absolute requirement for millimolar concentrations of glutathione or dithiothreitol. These cofactor characteristics suggest that both activities address distinct catalytic properties of GPx-1. 5-LO inhibition by GPx-1 was not due to direct GPx-5-LO protein-protein interactions, since GPx-1 did not bind to immobilized 5-LO. Interestingly, 5-LO derived from granulocytes was significantly more resistant against GPx-1 inhibition than B-lymphocytic 5-LO, which correlates with the respective cellular 5-LO activities. In summary, the data suggest that, in addition to previously reported phospholipid hydroperoxide glutathione peroxidase (GPx-4), GPx-1 is an efficient inhibitor of 5-LO even at low thiol concentrations, and is involved in the regulation of cellular 5-LO activity in various cell types.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Glutationa Peroxidase/metabolismo , Monócitos/enzimologia , Animais , Catálise , Células Cultivadas , Inibidores Enzimáticos/metabolismo , Estabilidade Enzimática , Humanos , Inibidores de Lipoxigenase , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Ligação Proteica , Ratos , Selênio/farmacologia , Compostos de Sulfidrila/metabolismo , Glutationa Peroxidase GPX1
13.
Insect Biochem Mol Biol ; 30(8-9): 711-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10876114

RESUMO

Eighteen peptides were isolated from brain extracts of the stick insect Carausius morosus. The peptides were purified in four steps by high-performance liquid chromatography, monitored by their ability to inhibit juvenile hormone biosynthesis by corpora allata of the cricket Gryllus bimaculatus in vitro, and chemically characterised by Edman degradation and mass spectrometry. We obtained complete primary-structure information for nine peptides, four of which belong to the peptide family characterised by a common C-terminal pentapeptide sequence -YXFGLamide. The remaining five belong to the W(2)W(9)amide peptide family, nonapeptides characterised by having the amino acid tryptophan in positions 2 and 9. The amino-acid sequence of two other peptides could not be completely resolved by means of Edman degradation; however, these peptides could be allocated to the -YXFGLamide and the W(2)W(9)amide family, respectively, by comparison of retention times, co-elution and mass spectrometry. Both classes of neuropeptides strongly inhibit juvenile hormone biosynthesis in crickets but show no inhibiting effect on the corpora allata of the stick insect.


Assuntos
Baratas/metabolismo , Gryllidae/metabolismo , Antagonistas de Hormônios/metabolismo , Neuropeptídeos/metabolismo , Peptídeos/metabolismo , Animais , Bioensaio , Corpora Allata/metabolismo , Antagonistas de Hormônios/química , Neuropeptídeos/química , Peptídeos/química , Análise de Sequência/métodos , Sesquiterpenos/metabolismo
14.
Eur J Biochem ; 267(12): 3869-73, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10849006

RESUMO

Three novel members of the periviscerokinin family could be identified directly from extracts of single abdominal perisympathetic organs of blaberoid cockroaches by means of electrospray ionization-quadrupole time of flight (ESI-QTOF) MS. Sequences of these periviscerokinins were confirmed by Edman degradation. Their primary structures are GSSGLIPFGRT-NH2 (Lem-PVK-1), GSSGLISMPRV-NH2 (Lem-PVK-2), and GSSGMIPFPRV-NH2 (Lem-PVK-3). Hitherto only known from the American cockroach, this neuropeptide family contains a highly conserved N-terminus whereas, at the C-terminus, only the penultimate amino-acid residue (Arg) has been found in all members of this peptide family. The identified periviscerokinins are the only abundant myoactive peptides in abdominal perisympathetic organs of blaberoid cockroches and they appear to be absent in the retrocerebral complex. Screening of extracts of single abdominal perisympathetic organs (70-90 microm in diameter), from five different species of the suborder Blaberoidea, revealed that they all contain the three neuropeptides which are described here for the first time.


Assuntos
Abdome/inervação , Proteínas de Insetos/isolamento & purificação , Proteínas de Insetos/metabolismo , Neuropeptídeos/isolamento & purificação , Neuropeptídeos/metabolismo , Abdome/anatomia & histologia , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Baratas , Coração/anatomia & histologia , Coração/efeitos dos fármacos , Neuropeptídeos/química , Neuropeptídeos/farmacologia , Análise de Sequência de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
J Hered ; 91(2): 158-62, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10768133

RESUMO

In Paederus riparius, (+) females able to biosynthesize the unique hemolymph toxin pederin and (-) females lacking this ability co-occur in natural populations. Larvae descended from both types of females were reared in the laboratory and the imagoes were crossed in order to get information about a possible genetic basis of this polymorphism. The daughters of (+) mothers become (+) females or (-) females, while the progeny of (-) mothers comprises only (-) females. This suggests a matrilineal trait because pederin biosynthesis cannot be inherited from the father. The rather stable proportion of nearly 90% (+) females in collected females is not maintained, however, when the beetles are reared in the laboratory. This observation is discussed with regard to artificial rearing conditions, where individuals are kept separate and cannot prey on conspecifics.


Assuntos
Besouros/genética , Polimorfismo Genético , Piranos/metabolismo , Toxinas Biológicas/metabolismo , Animais , Feminino
16.
J Trauma Stress ; 13(4): 589-609, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11109233

RESUMO

Imagery-rehearsal therapy for chronic nightmares was assessed in a randomized, controlled study of sexual assault survivors with posttraumatic stress disorder (PTSD). Nightmares, sleep quality, and PTSD were assessed at baseline for 169 women, who were randomized into two groups: treatment (n = 87) and wait-list control (n = 82). Treatment consisted of two 3-hr sessions and one 1-hr session conducted over 5 weeks. Of 169 participants, 91 women (Treatment, n = 43, Control, n = 48) completed a 3-month follow-up and 78 did not. At follow-up, nightmare frequency and PTSD severity decreased and sleep quality improved in the treatment group with small to minimal changes in the control group. Treatment effects were moderate to high (Cohen's d ranged from 0.57 to 1.26). Notwithstanding the large dropout rate, imagery-rehearsal therapy is an effective treatment for chronic nightmares in sexual assault survivors with PTSD and is associated with improvement in sleep quality and decreases in PTSD severity.


Assuntos
Sonhos/psicologia , Imagens, Psicoterapia/métodos , Delitos Sexuais/psicologia , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/terapia , Taxa de Sobrevida , Adulto , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Periodicidade , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Inquéritos e Questionários
17.
Fresenius J Anal Chem ; 366(6-7): 517-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11225764

RESUMO

Within the last five years the field of proteomics has changed the understanding of molecular biology. Proteins manifest physiological as well as pathophysiological processes in a cell or an organism, and proteomics describes the complete protein inventory in dependence on in vivo parameters. Disease mechanism or drug effects both affect a protein profile and, vice versa, characterising protein profiles reveals information for the understanding of disease and therapy. Analytical methods for proteomics are based on conventional tools for protein characterisation. The technical challenge is the complete coverage of physico-chemical properties for thousands of proteins. Nucleic acids display a relative chemical homogeneity and therefore genomics was considered more promising in the past than proteomics. Further improvements in proteomics technologies will likely change this course with proteomics complementing genomics as a tool to study life sciences.


Assuntos
Biologia Computacional , Proteoma , Animais , Bases de Dados como Assunto , Eletroforese em Gel Bidimensional , Genômica , Humanos , Espectrometria de Massas/métodos , Proteoma/química , Proteoma/genética , Proteoma/fisiologia
18.
J Biol Chem ; 274(51): 36722-8, 1999 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-10593978

RESUMO

Aerolysin is a bacterial pore-forming toxin that is secreted as an inactive precursor, which is then processed at its COOH terminus and finally forms a circular heptameric ring which inserts into membranes to form a pore. We have analyzed the stability of the precursor proaerolysin and the heptameric complex. Equilibrium unfolding induced by urea and guanidinium hydrochloride was monitored by measuring the intrinsic tryptophan fluorescence of the protein. Proaerolysin was found to unfold in two steps corresponding to the unfolding of the large COOH-terminal lobe followed by the unfolding of the small NH(2)-terminal domain. We show that proaerolysin contains two disulfide bridges which strongly contribute to the stability of the toxin and protect it from proteolytic attack. The stability of aerolysin was greatly enhanced by polymerization into a heptamer. Two regions of the protein, corresponding to amino acids 180-307 and 401-427, were identified, by limited proteolysis, NH(2)-terminal sequencing and matrix-assisted laser desorption ionization-time of flight, as being responsible for stability and maintenance of the heptamer. These regions are presumably involved in monomer/monomer interactions in the heptameric protein and are exclusively composed of beta structure. The stability of the aerolysin heptamer is reminiscent of that of pathogenic, fimbrial protein aggregates found in a variety of neurodegenerative diseases.


Assuntos
Toxinas Bacterianas/química , Sequência de Aminoácidos , Toxinas Bacterianas/genética , Dimerização , Dados de Sequência Molecular , Mutação , Proteínas Citotóxicas Formadoras de Poros , Conformação Proteica , Desnaturação Proteica , Ureia
19.
Psychosomatics ; 40(5): 380-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10479942

RESUMO

The authors determined the different effects of hypochondriasis and somatization on health perceptions, health status, and service utilization in a primary care population. The subjects with hypochondriacal responses (HR) on the Illness Attitudes Scales or high somatic concern (HSC) on the Symptom Questionnaire had a worse perception of health and variably used more health services than the control subjects, even though the HR and HSC subjects had the same level of chronic medical disorders. Regression analyses determined that somatization contributed more to negative health perception and service utilization than did hypochondriasis, although an interaction between the two contributed to the use of psychiatric care. The authors discuss the boundary between hypochondriasis and somatization for its implications for research and clinical practice.


Assuntos
Atitude Frente a Saúde , Medicina de Família e Comunidade/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Nível de Saúde , Hipocondríase , Transtornos Somatoformes , Adulto , Estudos de Casos e Controles , Feminino , Indicadores Básicos de Saúde , Humanos , Hipocondríase/psicologia , Hipocondríase/terapia , Masculino , New Mexico , Razão de Chances , Análise de Regressão , Transtornos Somatoformes/psicologia , Transtornos Somatoformes/terapia , Inquéritos e Questionários
20.
Psychosomatics ; 40(5): 387-95, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10479943

RESUMO

Better definition of the boundary between hypochondriasis and somatization was determined by measuring attitudes to self and personality dimensions associated with these syndromes. In this study, the primary care patients with hypochondriacal responses (HR) on the Illness Attitudes Scales or high somatic concern (HSC) on the Symptom Questionnaire had more negative attitudes to self and more psychological distress than the matched group of primary care control subjects. The HR subjects were different from the non-HR subjects on two of five personality domains on the NEO Personality Inventory (NEO)-Five-Factor Inventory, and the HSC subjects were different from the non-HSC subjects on four of five NEO domains. Analysis of variance demonstrated that somatization explained most of the variance in attitudes, personality, and psychological distress, but hypochondriasis uniquely contributed only to thanatophobia. The authors discuss the boundary between hypochondriasis and somatization and offer a descriptive model of this relationship.


Assuntos
Hipocondríase/psicologia , Personalidade , Autoimagem , Transtornos Somatoformes/psicologia , Adulto , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Modelos Psicológicos , Escalas de Graduação Psiquiátrica
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