RESUMO
BACKGROUND: Digital assistive technology (DAT) may support time management in people with dementia or mild cognitive impairment (MCI), but research on DAT for time management is limited. We aimed to explore how everyday could be supported by DAT for time management in persons with dementia or MCI from informal carers' perspectives. This study focused on a DAT device for time management called MEMOplanner (MMP). METHOD: Using a mixed-methods design, we utilized the Time-Proxy© questionnaire and a study-specific interview guide to investigate the perspectives of informal carers (n = 8) regarding the use of MMP by individuals with dementia or MCI. RESULT: The MMP was helpful in keeping track of time and activity. It helped to maintain an active lifestyle and facilitated communication. However, the MMP did not reduce the need for assistance from the informal carers, and it took time to learn the different functions of the device. Further research into employing a more extensive array of DAT for time management or other areas to assist individuals with dementia will yield valuable insights into enhancing and sustaining a higher quality of life despite cognitive decline.
Assuntos
Cuidadores , Disfunção Cognitiva , Demência , Tecnologia Assistiva , Humanos , Cuidadores/psicologia , Disfunção Cognitiva/psicologia , Disfunção Cognitiva/terapia , Feminino , Masculino , Demência/psicologia , Idoso , Gerenciamento do Tempo/métodos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Inquéritos e Questionários , Qualidade de Vida/psicologiaRESUMO
We describe the results of a survey of claim forms that are used when starting rehabilitation following inpatient treatment and of an evaluation of a claim form developed on the basis of the results. The survey of different existing forms shows a high overlapping in content, suggesting the possibility of unification to one claim form that can be accepted by all insurers. In analogy to the Delphi method criteria for evaluation were consented and applied by the author group to assess the relevance of the claim forms content items for the process of initiating rehabilitation. A group of further experts added their evaluations. We prioritised the results and extracted the essential contents to conceive a unified claim form eligible for all types of rehabilitation. The claim form was discussed in 3 focus groups, revised accordingly and tested in the Hannover Medical School. Test results show that all relevant information is asked for and that the form is well manageable. The users' request for an IT-based solution and further ideas for improvement were integrated into the revised and validated version of the claim form. It is now available for all stake holders, in particular for insurers, as a means to improve quality of care and efficiency by standardisation of rehabilitation claim forms.
Assuntos
Assistência ao Convalescente/normas , Controle de Formulários e Registros/normas , Formulário de Reclamação de Seguro/normas , Revisão da Utilização de Seguros/normas , Registros/normas , Reabilitação/normas , Documentação , Alemanha , Reembolso de Seguro de Saúde/normas , Guias de Prática Clínica como AssuntoRESUMO
The distribution of binding sites for human chorionic gonadotropin (hCG) in the preovulatory follicle was studied by autoradiography. An ovulatory dose (10 IU/rat) of [125I]hCG (1.4 muCi/IU) was administered intravenously, and large Graafian follicles were isolated 3 h later by microdissection. Injection of excess unlabeled hCG (500 IU/rat) prevented uptake of radioactivity by the follicle, indicating that binding of iodinated hormone was confined to specific and saturable receptor sites. The density of bound hormone molecules was highest in the theca interna and in three to four layers of mural granulosa cells adjacent to the basement membrane; labeling was chiefly associated with the cell borders. No significant binding could be detected either on the oocyte or on the cumulus cells surrounding the oocyte. We therefore suggest that the induction of ovum maturation does not require attachment of the hormone to the oocyte itself or to follicle cells in its immediate vicinity.
Assuntos
Gonadotropina Coriônica/metabolismo , Folículo Ovariano/metabolismo , Animais , Sítios de Ligação , Gonadotropina Coriônica/análise , Feminino , Células da Granulosa/análise , Células da Granulosa/metabolismo , Folículo Ovariano/análise , Ratos , Células Tecais/análise , Células Tecais/metabolismoRESUMO
Testicular temperature highly correlates with scrotal temperature. It has been postulated that cycling is associated with increased scrotal temperatures with time and consecutively with impaired semen quality. The aim of this study was to evaluate the influence of moderate cycling on scrotal temperature during highly standardized conditions in an experimental lab. A total of 25 volunteers without a history of infertility and normal andrological examination were included for scrotal temperature evaluation. Scrotal temperatures were measured every minute with a portable data recorder connected with two thermistor temperature sensors, which were attached on either side of the scrotum. A further thermistor sensor was attached on the central surface of the bicycle saddle. Ambient temperature in the study room was adjusted to 22 degrees C throughout the whole experiment. All volunteers started the experiment at the same daytime. Clothing of the volunteers consisted of standardized cotton wool trousers and shirts fitting to body size. After acclimatization to the study room in a sitting posture, each volunteer cycled on an exercise cycle for 60 min with a power of 25 Watt representing a speed of 25.45 km/h respectively. The saddle surface temperature reached in the median 35.59 degrees C after 60 min cycling. Median values of scrotal temperatures increased from 35.75 degrees C at the beginning to 35.82 degrees C after 60 min for the left side and from 35.50 to 35.59 degrees C for the right side. No correlation between cycling duration and scrotal temperatures could be found using multivariate anova for repeated measurements. However, scrotal temperatures during cycling were significantly lower (p < 0.001) compared with the last 10 min in sitting posture before starting cycling with a difference of 1.31 degrees C for the left and 1.46 degrees C for the right side. The present study suggests that moderate cycling under standardized conditions with a power of 25 Watt is not a major genital heat stress factor.
Assuntos
Ciclismo , Temperatura Corporal , Escroto/fisiologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Valores de ReferênciaRESUMO
In addition to their role in programmed cell death, caspases exert non-lethal functions in diverse developmental processes including cell differentiation or tissue remodeling. Terminal cell cycle exit and differentiation can be promoted by increased level of the CDK inhibitor p27(Kip1). Activated caspases cause proteolytic processing of p27, and we identified a novel caspase cleavage site in human p27 that removes a C-terminal fragment of 22 amino acids from the CDK inhibitor, including a phosphodegron. Thereby, caspases protect the inhibitor from SCF-Skp2-mediated degradation in S, G2 and M phases of the cell cycle. As a consequence, p27 becomes stabilized and remains an efficient nuclear inhibitor of cell cycle progression. Besides controlling cyclin/CDK kinase activity, p27 also regulates cytoskeletal dynamics, cell motility and cell invasion. Following processing by caspases, p27 fails to bind to RhoA and to inhibit its activation, and thereby abolishes the ability of p27 to stimulate cell migration and invasion. We propose that the stabilization of the CDK inhibitor and elimination of RhoA-induced cytoskeletal remodeling upon caspase processing could contribute to cell cycle exit and cytoskeletal remodeling during non-lethal caspase controlled differentiation processes.
Assuntos
Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Neoplasias/genética , Proteína rhoA de Ligação ao GTP/genética , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Citoesqueleto/genética , Humanos , Invasividade Neoplásica/genética , Neoplasias/patologia , Ligação Proteica , Proteólise , Proteínas Quinases Associadas a Fase S/genética , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismoRESUMO
1. High affinity macromolecular binding of the non-steroidal synthetic oestrogen [3H]diethylstilboestrol and of [3H] oestradiol-17beta in cytosol of Müllerian duct and uterus, and in blood plasma of perinatal rats, was investigated by sucrose density gradient sedimentation. 2. While [3H] oestradiol was bound to both the characteristic 8 S uterine cytoplasmic receptor and a 4 S component of uterine cytosol and plasma of 11-day-old rats, [3H] diethylstilboestrol was bound almost exclusively by the 8 S cytoplasmic receptor. 3. The greatly reduced binding of [3H] diethylstilboestrol to the 4 S plasma plasmic receptor in the Müllerian duct (precursor of the uterus) of 20-day-old foetuses.
Assuntos
Dietilestilbestrol/metabolismo , Estradiol/metabolismo , Ductos Paramesonéfricos/metabolismo , Receptores de Superfície Celular , Animais , Sítios de Ligação , Proteínas Sanguíneas/metabolismo , Citosol/metabolismo , Feminino , Feto , Proteínas Musculares/metabolismo , Gravidez , Ligação Proteica , Ratos , Útero/metabolismo , alfa-Fetoproteínas/metabolismoRESUMO
Culture of preovulatory rat follicles with luteinizing hormone, follicle-stimulating hormone or prostaglandin E2 for 24 h reduced the subsequent response of adenylate cyclase to the homologous by 80, 50 and 90%, respectively; yet follicles refractory to luteinizing hormone fully responded to follicle-stimulating hormone responded to luteinizing hormone and prostaglandin E2, and those refractory to prostaglandin E2 could be stimulated by either gonadotropin. Desensitization of the adenylate cyclase system by luteinizing hormone was achieved by hormone concentrations of 0.8--2.0 mug/ml in the medium; a lower dose of luteinizing hormone (0.4 mug/ml), though effective in stimulating adenylate cyclase, did not induce refractoriness. Prostaglandin E2 caused partial refractoriness at dose levels of 0.1--0.25 mug/ml; higher dose levels were more effective. These findings suggest that continued exposure to the preovulatory follicle to elevated levels of hormones may cause perturbations in either the interaction between the hormone and its specific receptor or in a subsequent step essential for activation of adenylate cyclase.
Assuntos
Adenilil Ciclases/metabolismo , Hormônio Foliculoestimulante/farmacologia , Hormônio Luteinizante/farmacologia , Folículo Ovariano/enzimologia , Prostaglandinas E/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Folículo Ovariano/efeitos dos fármacos , RatosRESUMO
Continued exposure of cultured granulosa cells to follicle-stimulating hormone (FSH) induced: (i) a rise in apparent membrane microviscosity, as reflected by an increase in fluorescence polarization of the lipid-soluble probe, 1,6-diphenyl-1,3,5,-hexatriene; and (ii) a progressive decline in the cyclic AMP response to renewed challenge with the same hormone. Both changes were reduced or prevented by pretreatment of the cells with oleic or linoleic acid, agents which reduce membrane viscosity, but not by elaidic or palmitic acid which increase the rigidity of membrane lipids. Other agents that inhibited FSH-induced changes in membrane fluidity (gonadotropin-releasing hormone, actinomycin D and cycloheximide) also prevented desensitization to FSH. Cyclic AMP and cyclic GMP derivatives did not mimic the effects of FSH on apparent membrane viscosity or desensitization. Changes in membrane fluidity are unlikely to be the sole cause of desensitization since (i) pretreatment of the cells with fatty acids that increase lipid viscosity did not induce desensitization to FSH, and (ii) desensitization of granulosa cells to lutropin and prostaglandin E2 by exposure to the homologous hormone was not attended by increased membrane viscosity. The experiments described provide the first example of a hormonally induced increase in the target cell apparent membrane viscosity.
Assuntos
Membrana Celular/ultraestrutura , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/ultraestrutura , Fluidez de Membrana/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Cinética , Lipídeos de Membrana/análise , Ácidos Oleicos/farmacologia , Ratos , Espectrometria de Fluorescência , ViscosidadeRESUMO
alpha-Tocopheryl succinate (alpha-TS) is a potent inhibitor of tumor cell proliferation. The goal of the present study was to investigate whether and to what extent alpha-TS associates with plasma lipoproteins and if alpha-TS-enriched lipoproteins inhibit breast cancer cell growth in a manner comparable to the free drug. In vitro enrichment of human plasma revealed that alpha-TS readily associated with the main lipoprotein classes, findings confirmed in vivo in mice. At the highest alpha-TS concentrations, lipoproteins carrying 50000 (VLDL), 5000 (LDL) and 700 (HDL) alpha-TS molecules per lipoprotein particle were generated. alpha-TS enrichment generated lipoprotein particles with slightly decreased density and increased particle radius. To study whether the level of LDL-receptor (LDL-R) expression affects alpha-TS uptake from apoB/E containing lipoprotein particles human breast cancer cells with low (MCF-7) and normal (HBL-100) LDL-R expression were used. The uptake of free, VLDL- and (apoE-free) HDL(3)-associated alpha-TS was nearly identical for both cell lines. In contrast, uptake of LDL-associated alpha-TS by HBL-100 cells (normal LDL-R expression) was about twice as high as compared to MCF-7 cells (low LDL-R expression). VLDL and LDL-associated alpha-TS inhibited proliferation most effectively at the highest concentration of alpha-TS used (100% inhibition of MCF-7 growth with 20 microg/ml of lipoprotein-associated alpha-TS). However, also alpha-TS-free VLDL and LDL inhibited HBL-100 cell proliferation up to 55%. In both cell lines, alpha-TS-enriched HDL(3) inhibited cell growth by 40-60%. Incubation of both cell lines in the presence of free or lipoprotein-associated alpha-TS resulted in DNA fragmentation indicative of apoptosis. Collectively, the present findings demonstrate that: (1) alpha-TS readily associates with lipoproteins in vitro and in vivo; (2) the lipoprotein-enrichment efficacy was dependent on the particle size and/or the triglyceride content of the lipoprotein; (3) uptake of LDL-associated alpha-TS was apparently dependent on the level of LDL-R expression; and (4) lipoproteins were efficient alpha-TS carriers inducing reduced cell proliferation rates and apoptosis in human breast cancer cells as observed for the free drug.
Assuntos
Apoptose/efeitos dos fármacos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Receptores de LDL/metabolismo , Vitamina E/análogos & derivados , Animais , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Feminino , Humanos , Hidrólise , Camundongos , Tocoferóis , Células Tumorais Cultivadas , Vitamina E/metabolismo , Vitamina E/farmacologiaRESUMO
Chromatin condensation paralleled by DNA fragmentation is one of the most important nuclear events occurring during apoptosis. Histone modifications, and in particular phosphorylation, have been suggested to affect chromatin function and structure during both cell cycle and cell death. We report here that phosphate incorporation into all H1 subtypes decreased rapidly after induction of apoptosis, evidently causing a strong reduction in phosphorylated forms of main H1 histone subtypes. H1 dephosphorylation is accompanied by chromatin condensation preceding the onset of typical chromatin oligonucleosomal fragmentation, whereas H2A.X hyperphosphorylation is strongly correlated to apoptotic chromatin fragmentation. Using various kinase inhibitors we were able to exclude some of the possible kinases which can be involved directly or indirectly in phosphorylation of histone H2A.X. Neither DNA-dependent protein kinase, protein kinase A, protein kinase G, nor the kinases driven by the mitogen-activated protein kinase (MAP) pathway appear to be responsible for H2A.X phosphorylation. The protein kinase C activator phorbol 12-myristate 13-acetate (PMA), however, markedly reduced the induction of apoptosis in TNFalpha-treated cells with a simultaneous change in the phosphorylation pattern of histone H2A.X. Hyperphosphorylation of H2A.X in apoptotic cells depends indirectly on activation of caspases and nuclear scaffold proteases as shown in zVAD-(OMe)-fmk- or zAPF-cmk-treated cells, whereas the dephosphorylation of H1 subtypes seems to be influenced solely by caspase inhibitors. Together, these results illustrate that H1 dephosphorylation and H2A.X hyperphosphorylation are necessary steps on the apoptotic pathway.
Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose/fisiologia , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Fator de Necrose Tumoral alfa/farmacologia , Células 3T3 , Animais , Anticorpos Monoclonais Murinos , Apoptose/efeitos dos fármacos , Cantaridina/farmacologia , Proteínas de Transporte/farmacologia , Eletroforese em Gel de Poliacrilamida , Ativadores de Enzimas/farmacologia , Inibidores Enzimáticos/farmacologia , Histonas/química , Camundongos , Fosforilação/efeitos dos fármacos , Inibidores de Proteases/farmacologiaRESUMO
T4 and T3 formation and their response to TSH, cAMP, and prostaglandin E2 (PGE2) stimulation were studied by RIA in cultured bovine fetal thyroids from 130 embryos of 1.2-25.0 cm crown-rump length (CRL). T4 and T3 were found in all of the freshly isolated glands studied, and their concentrations increased significantly (P less than 0.05) during a 24-h incubation of glands from fetuses with a CRL greater than 8.0 cm. The release of T4 (nanograms per mg tissue), but not of T3, increased consistently with CRL (r = 0.64; P less than 0.05). The addition of TSH (0.5 mU) to the culture medium induced a 2- to 3-fold increase in the secretion of T4, but not of T3, by glands of fetuses with a CRL of 3.0-25.0 cm (P less than 0.05). Dibutyryl cAMP (10(-4) M) and PGE2 (10(-4) M) had comparable effects. A combination of TSH and theophylline (1 mM) or of TSH and dibutyryl cAMP significantly enhanced the T4 released by cultured tissue into the medium (P less than 0.05) over that induced by either agonist, but the combined effect was not fully additive. The total PGE2 in the tissue and medium was not changed by the addition of 0.5 mU TSH, and indomethacin had no effect on TSH-induced T4 secretion. The data show that thyroids of fetuses that have reached a CRL of 3.0 cm have the enzymatic capacity to produce both T4 and T3, and T4 is the dominant product formed. While exogenous PGE2 at high concentrations stimulates fetal T4 secretion, it does not mediate the actions of TSH and cAMP on the fetal thyroid.
Assuntos
Glândula Tireoide/embriologia , Tireotropina/farmacologia , Adenosina/farmacologia , Animais , Bucladesina/farmacologia , Bovinos , Dinoprostona , Embrião de Mamíferos/fisiologia , Feminino , Idade Gestacional , Indometacina/farmacologia , Cinética , Masculino , Gravidez , Prostaglandinas E/metabolismo , Teofilina/farmacologia , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Tireotropina/fisiologia , Tiroxina/metabolismo , Tri-Iodotironina/metabolismoRESUMO
Graafian follicles explanted from proestrous rats before the preovulatory gonadotropin surge secreted predominantly 17beta-estradiol, and only small amounts of progestins and androgens, during 12 h of culture in hormone-free medium. Addition of ovine luteinizing hormone (NIH-LH-S18; 0.1-1.0 mug/ml) to the medium stimulated within 1-2 h the rate of accumulation of these steroids. However, accumulation of androstenedione and estradiol ceased after 4-6 h in the LH-treated cultures, whereas progesterone continued to accumulate and became the major secretory product at 6-12 h. Incubation of the follicles with LH for only 5 min resulted in significant stimulation of the accumulation of progesterone, androstenedione and estradiol during a subsequent 6-h culture period in hormone-free medium containing antibodies to LH; 30 min exposure to the hormone sufficed to elicit a maximal steroidogenic response and to induce ovum maturation in 95% of the follicles. Addition of actinomycin D (act D; 8 mug/ml) within the first hour after exposure of follicles to LH suppressed the LH-effect on progesterone but augmented the LH effect on estradiol accumulation; when addition of this inhibitor was delayed until 2 h, progesterone accumulation continued unabated for a further 10 h. By contrast, puromycin (80 mug/ml) inhibited progesterone accumulation when added to the medium at any time (1, 2 or 3 h) after the hormone. It is suggested that (i) a short-lived protein is essential for the stimulatory effect of LH on follicular steroidogenesis; (ii) the act D-sensitive product (mRNA?) required for the production of this protein is synthesized in adequate amount during the first 2 h of LH action, and is stable for at least 10 h; and (iii) LH may stimulate the production of an additional act D-sensitive regulatory protein that inhibits enzymes engaged in the cleavage of the 17-side-chain of progesterone, or cells equipped with these enzymes.
Assuntos
Hormônio Luteinizante/farmacologia , Folículo Ovariano/metabolismo , Esteroides/biossíntese , Adenosina/metabolismo , Androstenodiona/biossíntese , Animais , Células Cultivadas , DNA/biossíntese , Dactinomicina/farmacologia , Estradiol/biossíntese , Feminino , Hidroxiprogesteronas/biossíntese , Leucina/metabolismo , Folículo Ovariano/efeitos dos fármacos , Gravidez , Proestro , Progesterona/biossíntese , Biossíntese de Proteínas , Puromicina/farmacologia , RNA/biossíntese , Radioimunoensaio , Ratos , Fatores de TempoRESUMO
Reference preparations of ovine follicle-stimulating hormone (NIH-FSH-S8 and S9; 10-50 mug/ml) induced ovum maturation and stimulated cyclic AMP formation, as well as progesterone and 17beta-estradiol secretion, by rat Graafian follicles in vitro. These actions of NIH-FSH were retained after immunoabsorption of any contaminating luteinizing hormone (LH) present in the preparations, by treatment with an antiserum to the beta-subunit of purified ovine LH (anti-betaLH). In contrast, the corresponding biological actions of NIH-LH-S18 (0.5-10 mug/ml) were abolished by treatment with this anti-betaLH serum. A highly purified FSH preparation (64-96 CD, 0.25 mug/ml) also triggered oocytic meiosis and increased follicular progesterone secretion in vitro. Intraperitoneal (ip) administration of anti-betaLH-treated NIH-FSH-S9 (50 mug/rat at 1430 h) consistently induced ovulation in proestrous rats in which the endogenous gonadotropin surge had been blocked by ip injection of either Nembutal (1345 h) or antiserum to the LH-releasing hormone (1200 h). Injection (ip) of anti-betaLH serum on its own into proestrous rats at 1200 h prevented ovum maturation and follicular rupture. We conclude that currently available reference preparations of ovine FSH possess the capacity to stimulate follicular adenylate cyclase, steroidogenesis, and ovum maturation in vitro, as well as ovulation in vivo, in the rat, and that this capacity cannot be attributed to contamination with material immunochemically identical with LH. However, it is inferred that the physiological triggering of ovulation and related events in this species depends principally on LH.
Assuntos
AMP Cíclico/metabolismo , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/metabolismo , Ovulação/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Animais , Estradiol/biossíntese , Feminino , Hormônio Foliculoestimulante/imunologia , Hormônio Foliculoestimulante/isolamento & purificação , Hormônio Liberador de Gonadotropina/imunologia , Soros Imunes , Hormônio Luteinizante/fisiologia , Folículo Ovariano/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Pentobarbital/farmacologia , Progesterona/biossíntese , Ratos , Estimulação QuímicaRESUMO
Two 125I-labeled analogs of GnRH, [acidobenzoyl-D-Lys6]GnRH (I) and [D-Lys6]GnRH (II) were used for the localization of GnRH receptors in pituitary cells. The analogs exhibited high binding affinity to pituitary membrane preparations and after photoactivation (analog I) or cross-linking with glutaraldehyde (analog II), these analogs are bound covalently to pituitary cells. The distribution of the labeled hormones by light and electron microscopic autoradiography indicated that after exposure of pituitary cells to 125I-labeled hormones at 4 C (90 min), most of the labeled hormones were associated with the cell surface membrane, while at 37 degrees C (30 min) most of the cell-bound labeled hormones were internalized.
Assuntos
Azidas , Hipófise/ultraestrutura , Receptores de Superfície Celular/análise , Animais , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/metabolismo , Métodos , Microscopia Eletrônica , Hipófise/metabolismo , Ratos , Receptores de Superfície Celular/metabolismo , Receptores LHRHRESUMO
The cytoplasmic B-type histone acetyltransferase was purified to apparent homogeneity from maize embryos. We established a novel protocol for easy large-scale preparation of acetylated core histone species, using preparative acetic acid-urea-Triton PAGE. The pure maize histone acetyltransferase B was highly specific for histone H4 under various assay conditions, modifying H4 up to the di-acetylated isoform. Only non-acetylated H4 isoform was accepted as substrate, whereas mono-acetylated H4 could not be further acetylated. The enzyme selectively acetylated lysines 12 and 5 in a sequential manner. The same results were obtained with a partially purified cytoplasmic histone acetyltransferase of rat liver. Protein sequencing results were supported by immunological characterization of acetylated H4 subspecies with site-specific H4-acetyllysine antibodies.
Assuntos
Acetiltransferases/metabolismo , Fígado/enzimologia , Proteínas de Saccharomyces cerevisiae , Zea mays/enzimologia , Acetilação , Acetiltransferases/isolamento & purificação , Animais , Galinhas , Citoplasma , Histona Acetiltransferases , Histonas/metabolismo , Ratos , Especificidade por SubstratoRESUMO
DEAE-Sepharose chromatography of extracts from plasmodia of the myxomycete Physarum polycephalum revealed the presence of multiple histone acetyltransferases and histone deacetylases. A cytoplasmic histone acetyltransferase B, specific for histone H4, and two nuclear acetyltransferases A1 and A2 were identified; A1 acetylates all core histones with a preference for H3 and H2A, whereas A2 is specific for H3 and also slightly for H2B. Two histone deacetylases, HD1 and HD2, could be discriminated. They differ with respect to substrate specificity and pH dependence. For the first time the substrate specificity of histone deacetylases was determined using HPLC-purified individual core histone species. The order of acetylated substrate preference is H2A much greater than H3 greater than or equal to H4 greater than H2B for HD1 and H3 greater than H2A greater than H4 for HD2, respectively; HD2 is inactive with H2B as substrate. Moreover histone deacetylases are very sensitive to butyrate, since 2 mM butyrate leads to more than 50% inhibition of enzyme activity.
Assuntos
Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Histonas/metabolismo , Isoenzimas/metabolismo , Physarum polycephalum/metabolismo , Proteínas de Saccharomyces cerevisiae , Acetilação , Acetiltransferases/isolamento & purificação , Animais , Butiratos/farmacologia , Ácido Butírico , Galinhas , Cromatografia Líquida de Alta Pressão , Eritrócitos/metabolismo , Histona Acetiltransferases , Inibidores de Histona Desacetilases , Histona Desacetilases/isolamento & purificação , Isoenzimas/isolamento & purificação , Cinética , Physarum polycephalum/enzimologia , Processamento de Proteína Pós-Traducional , Especificidade por SubstratoRESUMO
Twenty-six patients with migraine attacks were treated for 3 to 16 months with flufenamic acid (125 mg four to six times per attack), an inhibitor of prostaglandin synthesis and action. In 25 patients the drug afforded symptomatic relief in 195 of 200 treated attacks. Side effects observed were mild dyspepsia (eight patients) and severe upper gastrointestinal symptoms (two patients). None of the eight patients treated with placebo reported any relief (20 attacks). The "common" antimigraine drugs afforded symptomatic relief in 12 of the patients, partial relief in seven, and no relief in seven. Treatment with flufenamic acid was based on the hypothesis that prostaglandins are involved in migraine attack and that the drug relieves migraine by inhibition of the vasoactivity of prostaglandins.
Assuntos
Ácido Flufenâmico/uso terapêutico , Transtornos de Enxaqueca/tratamento farmacológico , Prostaglandinas/biossíntese , Adolescente , Adulto , Criança , Relação Dose-Resposta a Droga , Dispepsia/induzido quimicamente , Feminino , Ácido Flufenâmico/administração & dosagem , Ácido Flufenâmico/efeitos adversos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Aminoacylase I (Acy-1, EC 3.5.1.14) is found in many mammalian tissues, with highest activities occurring in kidney. The enzyme hydrolyzes a variety of N-acylated amino acids; however, the physiological role and the exact cellular localization of Acy-1 are still a matter of debate. The comparison of Acy-1 activities in kidney and liver homogenates of 11 mammalian species showed that the enzyme is most abundant in true herbivores such as sheep and cattle as well as in omnivores, while activities were very low in both rodents and the cat. Acy-1 activity was not detected in livers of dogs of five different breeds. Using in situ hybridization of porcine kidney sections with DIG-labeled RNA probes, Acy-1 mRNA was shown to be evenly distributed throughout the tubular system, while glomeruli and the interstitium were free of stain. During subcellular fractionation, porcine Acy-1 behaved like a typical cytosolic enzyme. Commonly, Acy-1 is thought to catalyze hydrolytic reactions, i.e., the formation of free amino acids from acylated derivatives. Based on the present results and literature data, we propose a novel hypothesis, i.e., that Acy-1 catalyzes the synthesis (rather than the hydrolysis) of hippurate that is formed as a detoxification product of aromatic compounds.
Assuntos
Amidoidrolases/metabolismo , Rim/enzimologia , Amidoidrolases/genética , Amidoidrolases/isolamento & purificação , Animais , Centrifugação com Gradiente de Concentração , Humanos , Hibridização In Situ/métodos , Mamíferos , Especificidade da Espécie , Frações Subcelulares , SuínosRESUMO
Eighty-four patients with an ovarian carcinoma Stage I-III received an adjuvant whole abdominal irradiation (WAI) with pelvic boost postoperatively. Surgery included a bilateral salpingo-oophorectomy, hysterectomy, and omentectomy in 59% of the patients; in 41% surgery was less radical. For the whole abdominal irradiation we used the moving-strip method on 43 patients. The open-field technique was used on the other patients. Median dose of WAI was 22.5 Gy and median pelvic dose was 45.5 Gy. After a median follow-up of 68.5 months, a 5-year survival rate of 64 +/- 5.7% was determined, as well as a 5-year NED rate of 61.2 +/- 5.7%. Five-year survival rate was 80.1 +/- 7.4% in Stage I, 64.1 +/- 9.7% in Stage II, and 35.4 +/- 11.6% in Stage III. Five-year survival depended on tumor rest significantly. There was a trend to better prognosis when surgery was complete and grade was G1 or G2. The risk factor according to Dembo proved to be the most reliable prognostic factor: the 5-year survival rates were 75.0 +/- 6.3% for patients with intermediate risk and 20.1 +/- 10.4% for those with high risk (p = 0.001). Side effects were generally well tolerated. We only saw one serious complication, a radiation-induced small bowel obstruction.