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1.
Front Med (Lausanne) ; 10: 1271863, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869162

RESUMO

Introduction: Long-term pulmonary dysfunction (L-TPD) is one of the most critical manifestations of long-COVID. This lung affection has been associated with disease severity during the acute phase and the presence of previous comorbidities, however, the clinical manifestations, the concomitant consequences and the molecular pathways supporting this clinical condition remain unknown. The aim of this study was to identify and characterize L-TPD in patients with long-COVID and elucidate the main pathways and long-term consequences attributed to this condition by analyzing clinical parameters and functional tests supported by machine learning and serum proteome profiling. Methods: Patients with L-TPD were classified according to the results of their computer-tomography (CT) scan and diffusing capacity of the lungs for carbon monoxide adjusted for hemoglobin (DLCOc) tests at 4 and 12-months post-infection. Results: Regarding the acute phase, our data showed that L-TPD was favored in elderly patients with hypertension or insulin resistance, supported by pathways associated with vascular inflammation and chemotaxis of phagocytes, according to computer proteomics. Then, at 4-months post-infection, clinical and functional tests revealed that L-TPD patients exhibited a restrictive lung condition, impaired aerobic capacity and reduced muscular strength. At this time point, high circulating levels of platelets and CXCL9, and an inhibited FCgamma-receptor-mediated-phagocytosis due to reduced FcγRIII (CD16) expression in CD14+ monocytes was observed in patients with L-TPD. Finally, 1-year post infection, patients with L-TPD worsened metabolic syndrome and augmented body mass index in comparison with other patient groups. Discussion: Overall, our data demonstrated that CT scan and DLCOc identified patients with L-TPD after COVID-19. This condition was associated with vascular inflammation and impair phagocytosis of virus-antibody immune complexes by reduced FcγRIII expression. In addition, we conclude that COVID-19 survivors required a personalized follow-up and adequate intervention to reduce long-term sequelae and the appearance of further metabolic diseases.

2.
Sci Rep ; 13(1): 17340, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833336

RESUMO

Atxurra cave has a decorated assemblage composed of more than a hundred engraved animal depictions. All of them are located in deep parts of the cave and most of them are hidden in raised areas, away from the main path. The main sector is the "Ledge of the Horses", located at 330 m from the entrance of the cave. It is a space of 12 m long and 1.5 m wide, elevated 4 m above the cave floor. This area includes almost fifty engraved and painted animals accompanied by a dozen flint tools, three fireplaces, and around one hundred charcoal fragments from torches. This extraordinary archaeological record allows us to value the complexity of the artistic production inside the caves during the Upper Palaeolithic. Our study has confirmed that there is planning prior to artistic production, both in terms of the iconographic aspects (themes, techniques, formats), its location (visibility, capacity), and the lighting systems. Furthermore, the data indicates the panel was decorated to be seen by third parties from different positions and was expressly illuminated for this purpose. This evidence supports the role of rock art as a visual communication system in Upper Palaeolithic societies.


Assuntos
Arte , Cavernas , Animais , Cavalos , Espanha , Motivação , Gravuras e Gravação , Arqueologia
3.
Rev. chil. pediatr ; 91(6): 908-916., dic. 2020. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1508046

RESUMO

INTRODUCCIÓN: La inmunodeficiencia combinada severa (IDCS) corresponde a una de las formas más graves de inmunodeficiencia primaria, existiendo escasos datos nacionales sobre ésta. OBJETIVO: describir la epidemiología, complicaciones, pronóstico y uso de la vacuna BCG en pacientes chilenos con IDCS. PACIENTES Y MÉTODO: Estudio retrospectivo de pacientes diagnosticados con IDCS entre los años 1999 y 2020 por médicos inmunólogos a lo largo de Chile. El diagnóstico de IDCS se realizó conforme a los criterios propuestos por Shearer: linfocitos T (CD3+) < 300 células/μL y prolife ración 10% del límite de normalidad en respuesta a fitohemaglutinina o presencia de linfocitos T de origen materno. Se obtuvieron de la ficha clínica los datos correspondientes a: sexo, edad al diagnóstico, consanguinidad, región de origen, subpoblaciones linfocitarias, diagnóstico genético, complicaciones infecciosas y no infecciosas, vacunación BCG y sus complicaciones, edad de deriva ción al centro de TPH y causa de mortalidad no relacionada al TPH. RESULTADOS: se diagnosticaron 25 casos de IDCS en 22 familias entre los años 1999-2020. 78% varones, la edad media a la primera manifestación fue 2.3 meses (0-7), mientras que la edad media al diagnóstico fue de 3.4 meses (0 7). Un 16% de los casos tenía un antecedente familiar de IDCS. Un 40% de los casos fueron diag nosticados en la Región Metropolitana. El inmunofenotipo más frecuente fue T-B-NK+ (48%). Se realizaron estudios genéticos en 69,5% de los casos, siendo los defectos genéticos en RAG2 (39%) la causa más frecuente. Un 88% de los casos recibió la vacuna Bacillus Calmette-Guerin (BCG) previo al diagnóstico, incluidos 2 pacientes con historia familiar positiva, 36% de los vacunados experimentó complicaciones de la BCG. La edad media a la derivación a trasplante fue de 7,4 meses (5-16). De los 25 pacientes, 11 fallecieron previo a la derivación a un centro de trasplante. CONCLUSIÓN: En Chile existe un retraso clínicamente significativo entre las primeras manifestaciones y el diagnóstico de IDCS, así como un importante retraso en la derivación a centros de trasplante. La mayoría de los pacientes con IDCS reciben la vacuna BCG, pese a tener antecedentes familiares, y experimentan frecuentemente complicaciones de la vacuna.


INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/μL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Vacina BCG/administração & dosagem , Vacinação/estatística & dados numéricos , Imunodeficiência Combinada Severa/epidemiologia , Prognóstico , Fatores de Tempo , Proteínas Nucleares/genética , Vacina BCG/efeitos adversos , Linfócitos T/imunologia , Chile , Estudos Retrospectivos , Transplante de Medula Óssea/estatística & dados numéricos , Vacinação/efeitos adversos , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/terapia , Proteínas de Ligação a DNA/genética , Diagnóstico Tardio , Mutação
4.
Arterioscler Thromb Vasc Biol ; 40(10): 2508-2515, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32757650

RESUMO

OBJECTIVE: Characterize homozygous familial hypercholesterolemia (HoFH) individuals from Iberoamerica. Approach and Results: In a cross-sectional retrospective evaluation 134 individuals with a HoFH phenotype, 71 adults (age 39.3±15.8 years, 38.0% males), and 63 children (age 8.8±4.0 years, 50.8% males) were studied. Genetic characterization was available in 129 (96%). The majority (91%) were true homozygotes (true HoFH, n=79, 43.0% children, 46.8% males) or compound heterozygotes (compound heterozygous familial hypercholesterolemia, n=39, 51.3% children, 46.2% males) with putative pathogenic variants in the LDLR. True HoFH due to LDLR variants had higher total (P=0.015) and LDL (low-density lipoprotein)-cholesterol (P=0.008) compared with compound heterozygous familial hypercholesterolemia. Children with true HoFH (n=34) tended to be diagnosed earlier (P=0.051) and had a greater frequency of xanthomas (P=0.016) than those with compound heterozygous familial hypercholesterolemia (n=20). Previous major cardiovascular events were present in 25 (48%) of 52 children (missing information in 2 cases), and in 43 (67%) of 64 adults with LDLR variants. Children who are true HoFH had higher frequency of major cardiovascular events (P=0.02), coronary heart (P=0.013), and aortic/supra-aortic valve diseases (P=0.022) than compound heterozygous familial hypercholesterolemia. In adults, no differences were observed in major cardiovascular events according to type of LDLR variant. From 118 subjects with LDLR variants, 76 (64%) had 2 likely pathogenic or pathogenic variants. In 89 subjects with 2 LDLR variants, those with at least one null allele were younger (P=0.003) and had a greater frequency of major cardiovascular events (P=0.038) occurring at an earlier age (P=0.001). CONCLUSIONS: There was a high frequency of cardiovascular disease even in children. Phenotype and cardiovascular complications were heterogeneous and associated with the type of molecular defect.


Assuntos
Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/sangue , Homozigoto , Hiperlipoproteinemia Tipo II/genética , Mutação , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Adulto , Fatores Etários , Apolipoproteína B-100/genética , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico , Criança , Pré-Escolar , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Predisposição Genética para Doença , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Fenótipo , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Estudos Retrospectivos , Fatores de Risco , América do Sul/epidemiologia , Adulto Jovem
5.
Rev Chil Pediatr ; 91(6): 908-916, 2020 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-33861827

RESUMO

INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/µL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.


Assuntos
Vacina BCG/administração & dosagem , Imunodeficiência Combinada Severa/epidemiologia , Vacinação/estatística & dados numéricos , Vacina BCG/efeitos adversos , Transplante de Medula Óssea/estatística & dados numéricos , Chile , Proteínas de Ligação a DNA/genética , Diagnóstico Tardio , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Proteínas Nucleares/genética , Prognóstico , Estudos Retrospectivos , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/terapia , Linfócitos T/imunologia , Fatores de Tempo , Vacinação/efeitos adversos
7.
Rev. méd. Chile ; 138(11): 1365-1372, nov. 2010. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-572953

RESUMO

Background: The frequency of obesity is increasing steadily in Chile. Aim: To assess the prevalence of obesity and overweight in children and teenagers living in three southern Chilean cities. Material and Methods: The database of an evaluation performed in 2006 in schools, was used to obtain weight and height of 32514 subjects aged 12 ± 4 years (48 percent males). Criteria proposed by the International Obesity Task Force (IOTF) and the Centers for Disease Control (CDC) were used to define obesity and overweight. Results: According to CDC criteria the prevalence of overweight and obesity was 11.2 percent and 6.5 percent, respectively. According to IOTF criteria, the fgures were 13.2 and 4 percent, respectively. The higher frequency of overweight and obesity was observed among children aged less than eight years. Conclusions: There is a high frequency of obesity and overweight in the studied sample.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Chile/epidemiologia , Modelos Logísticos , Sobrepeso/epidemiologia , Prevalência , Valores de Referência , Fatores de Risco , Instituições Acadêmicas
8.
J Cell Biochem ; 111(5): 1099-106, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20506357

RESUMO

Recently many authors have reported that cathepsin L can be found in the nucleus of mammalian cells with important functions in cell-cycle progression. In previous research, we have demonstrated that a cysteine protease (SpH-protease) participates in male chromatin remodeling and in cell-cycle progression in sea urchins embryos. The gene that encodes this protease was cloned. It presents a high identity sequence with cathepsin L family. The active form associated to chromatin has a molecular weight of 60 kDa, which is higher than the active form of cathepsin L described until now, which range between 25 and 35 kDa. Another difference is that the zymogen present in sea urchin has a molecular weight of 75 and 90 kDa whereas for human procathepsin L has a molecular weight of 38-42 kDa. Based on these results and using a polyclonal antibody available in our laboratory that recognizes the active form of the 60 kDa nuclear cysteine protease of sea urchin, ortholog to human cathepsin L, we investigated the presence of this enzyme in HeLa and Caco-2 cells. We have identified a new nuclear protease, type cathepsin L, with a molecular size of 60 kDa, whose cathepsin activity increases after a partial purification by FPLC and degrade in vitro histone H1. This protease associates to the mitotic spindle during mitosis, remains in the nuclei in binuclear cells and also translocates to the cytoplasm in non-proliferative cells.


Assuntos
Células CACO-2/enzimologia , Catepsina L , Cisteína Proteases/análise , Células HeLa/enzimologia , Ouriços-do-Mar/enzimologia , Transporte Ativo do Núcleo Celular , Animais , Ciclo Celular , Clonagem Molecular , Cisteína Proteases/química , Cisteína Proteases/genética , Feminino , Humanos , Masculino , Proteínas Nucleares/análise , Homologia de Sequência , Fuso Acromático/metabolismo
9.
Rev Med Chil ; 138(11): 1365-72, 2010 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-21279248

RESUMO

BACKGROUND: The frequency of obesity is increasing steadily in Chile. AIM: To assess the prevalence of obesity and overweight in children and teenagers living in three southern Chilean cities. MATERIAL AND METHODS: The database of an evaluation performed in 2006 in schools, was used to obtain weight and height of 32514 subjects aged 12 ± 4 years (48% males). Criteria proposed by the International Obesity Task Force (IOTF) and the Centers for Disease Control (CDC) were used to define obesity and overweight. RESULTS: According to CDC criteria the prevalence of overweight and obesity was 11.2% and 6.5%, respectively. According to IOTF criteria, the fgures were 13.2 and 4%, respectively. The higher frequency of overweight and obesity was observed among children aged less than eight years. CONCLUSIONS: There is a high frequency of obesity and overweight in the studied sample.


Assuntos
Obesidade/epidemiologia , Adolescente , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Sobrepeso/epidemiologia , Prevalência , Valores de Referência , Fatores de Risco , Instituições Acadêmicas
10.
J Cell Physiol ; 216(3): 790-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18425772

RESUMO

We have previously reported that sperm histones (SpH) degradation after fertilization is catalyzed by a cystein-protease (SpH-protease). Its inhibition blocks the degradation of SpH in vivo and also aborts sea urchin development at the initial embryonic cell cycles. It remains unknown if this effect is a consequence of the persistence of SpH on zygotic chromatin, or if this protease is involved per-se in the progression of the embryonic cell cycles. To discriminate among these two options we have inhibited this protease at a time when male chromatin remodeling was completed and the embryos were engaged in the second cell cycle of the cleavage divisions. The role of this enzyme in cell cycle was initially analyzed by immuno-inhibiting its SpH degrading activity in one of the two blastomeres after the initial cleavage division, while the other blastomere was used as a control. We found that in the blastomere injected with the anti-SpH-protease antibodies the cytokinesis was arrested, the chromatin failed to decondense after mitosis and BrdU incorporation into DNA was blocked. Since the N-terminal sequence and the SpH protease was homologous to the cathepsin L (Cat L) family of proteases, we subsequently investigated if the deleterious effect of the inhibition of this protease is related to its Cat L activity. In this context we analyzed the effect of Cat L inhibitor I (Z-Phe-Phe-CH(2)F) on embryonic development. We found that the addition of 100 uM of this inhibitor to the embryos harvested at the time of the initial cleavage division (80 min p.i.) mimics perfectly the effects of the immuno-inhibition of this enzyme obtained by microinjecting the anti-SpH-protease antibodies. Taken together these results indicate that the activity of this protease is required for embryonic cell cycle progression. Interestingly, we observed that when this protease was inhibited the chromatin decondensation after mitosis was abolished indicating that the inhibition of this enzyme affects chromosomes decondensation after mitosis.


Assuntos
Catepsinas/antagonistas & inibidores , Divisão Celular/fisiologia , Cromossomos/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Mitose/fisiologia , Ouriços-do-Mar , Animais , Catepsina L , Catepsinas/metabolismo , Cisteína Endopeptidases/metabolismo , Replicação do DNA , Masculino , Ouriços-do-Mar/embriologia , Ouriços-do-Mar/genética
11.
J Cell Biochem ; 101(1): 1-8, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17340626

RESUMO

Previously we have identified a cysteine-protease involved in male chromatin remodeling which segregates into the nuclei of the two blastomeres at the first cleavage division. Here we have investigated the fate of this protease during early embryogenesis by immunodetecting this protein with antibodies elicited against its N-terminal sequence. As shown in this report, the major 60 kDa active form of this protease was found to be present in the extracts of chromosomal proteins obtained from all developmental stages analyzed. In morula and gastrula the 70 kDa inactive precursor, which corresponds to the major form of the zymogen found in unfertilized eggs, was detected. In plutei larvas, the major 60 kDa form of this enzyme was found together with a higher molecular weight precursor (90 kDa) which is consistent with the less abundant zymogen primarily detected in unfertilized eggs. As reported here, either the active protease or its zymogens were visualized in most of the embryonic territories indicating that this enzyme lacks a specific pattern of spatial-temporal developmental segregation. Taken together our results indicate that this protease persists in the embryo and is ubiquitously distributed up to larval stages of development, either as an active enzyme and/or as an inactive precursor. These results suggest that this enzyme may display yet unknown functions during embryonic development that complement its role in male chromatin remodeling after fertilization.


Assuntos
Núcleo Celular/enzimologia , Montagem e Desmontagem da Cromatina/fisiologia , Cisteína Endopeptidases/imunologia , Fertilização , Ouriços-do-Mar/embriologia , Animais , Anticorpos/farmacologia , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Embrião não Mamífero , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Masculino , Fatores de Tempo , Distribuição Tecidual
12.
J Cell Biochem ; 98(2): 335-42, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16408295

RESUMO

We reported recently that the inhibition of cysteine-proteases with E-64-d disturbs DNA replication and prevents mitosis of the early sea urchin embryo. Since E-64-d is a rather general inhibitor of thiol-proteases, to specifically target the cysteine-protease previously identified in our laboratory as the enzyme involved in male chromatin remodeling after fertilization, we injected antibodies against the N-terminal sequence of this protease that were able to inhibit the activity of this enzyme in vitro. We found that injection of these antibodies disrupts the initial zygotic cell cycle. As shown in this report in injected zygotes a severe inhibition of DNA replication was observed, the mitotic spindle was not correctly bipolarized the embryonic development was aborted at the initial cleavage division. Consequently, the injection of these antibodies mimics perfectly the effects previously described for E-64-d, indicating that the effects of this inhibitor rely mainly on the inhibition of the cysteine-protease involved in male chromatin remodeling after fertilization. These results further support the crucial role of this protease in early embryonic development.


Assuntos
Ciclo Celular/imunologia , Montagem e Desmontagem da Cromatina/fisiologia , Cisteína Endopeptidases/imunologia , Inibidores de Cisteína Proteinase/imunologia , Ouriços-do-Mar/embriologia , Animais , Anticorpos/farmacologia , Ciclo Celular/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Replicação do DNA/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Fertilização/fisiologia , Imunoglobulinas/efeitos dos fármacos , Leucina/análogos & derivados , Leucina/farmacologia , Masculino , Microinjeções/métodos , Mitose/efeitos dos fármacos , Zigoto/citologia
13.
J Cell Biochem ; 96(2): 235-41, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16088960

RESUMO

Male pronucleus formation involves sperm nucleus decondensation and sperm chromatin remodeling. In sea urchins, male pronucleus decondensation was shown to be modulated by protein kinase C and a cdc2-like kinase sensitive to olomoucine in vitro assays. It was further demonstrated that olomoucine blocks SpH2B and SpH1 phosphorylation. These phosphorylations were postulated to participate in the initial steps of male chromatin remodeling during male pronucleus formation. At final steps of male chromatin remodeling, all sperm histones (SpH) disappear from male chromatin and are subsequently degraded by a cysteine protease. As a result of this remodeling, the SpH are replaced by maternal histone variants (CS). To define if sperm nucleus decondensation is coupled with sperm chromatin remodeling, we have followed the loss of SpH in zygotes treated with olomoucine. SpH degradation was followed with anti-SpH antibodies that had no cross-reactivity with CS histone variants. We found that olomoucine blocks SpH1 and SpH2B phosphorylation and inhibits male pronucleus decondensation in vivo. Interestingly, the normal schedule of SpH degradation remains unaltered in the presence of olomoucine. Taken together these results, it was concluded that male nucleus decondensation is uncoupled from the degradation of SpH associated to male chromatin remodeling. From these results, it also emerges that the phosphorylation of SpH2B and SpH1 is not required for the degradation of the SpH that is concurrent to male chromatin remodeling.


Assuntos
Núcleo Celular , Montagem e Desmontagem da Cromatina , Ouriços-do-Mar/citologia , Ouriços-do-Mar/genética , Animais , Fertilização , Histonas/metabolismo , Masculino , Fosforilação , Ouriços-do-Mar/embriologia , Espermatozoides/metabolismo
14.
J Cell Physiol ; 202(2): 602-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15389576

RESUMO

We postulated an essential role for a cysteine-protease in sea urchins sperm histones degradation which follows fertilization. We now report the purification of this enzyme, the determination of its N-terminal amino acid sequence and the localization of the protein with antibodies generated against this amino-terminal peptide. The immunofluorescence data confirmed the presence of this enzyme in the nucleus of unfertilized eggs. After fertilization labeling is observed both in female and male pronuclei suggesting a rapid recruitment of the enzyme to the male pronuclei. Interestingly, we have found that this cysteine-protease persists in the nucleus of the zygotes during S phase of the cell cycle and co-localizes with alpha-tubulin that organizes the mitotic spindle during the initial embryonic cell division.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Cisteína Endopeptidases/fisiologia , Fertilização/fisiologia , Mitose/fisiologia , Ouriços-do-Mar , Tubulina (Proteína)/metabolismo , Animais , Núcleo Celular/enzimologia , Cisteína Endopeptidases/metabolismo , Feminino , Immunoblotting , Imuno-Histoquímica , Masculino , Óvulo/metabolismo , Fase S , Ouriços-do-Mar/embriologia , Distribuição Tecidual , Zigoto/citologia , Zigoto/enzimologia , Zigoto/metabolismo
15.
J Cell Biochem ; 88(4): 643-9, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12577298

RESUMO

Three sets of histone variants are coexisting in the embryo at larval stages of sea urchin's development: the maternally inherited cleavage stage variants (CS) expressed during the two initial cleavage divisions, the early histone variants, which are recruited into embryonic chromatin from middle cleavage stages until hatching and the late variants, that are fundamentally expressed from blastula stage onward. Since the expression of the CS histones is confined to the initial cleavage stages, these variants represent a very minor proportion of the histones present in the plutei larvae, whereas the late histone variants are predominant. To determine the position of these CS in the embryonic territories, we have immunolocalized the CS histone variants in plutei larvas harvested 72 h post-fertilization. In parallel, we have pulse labeled the DNA replicated during the initial cleavage cycle with bromodeoxyuridine (BrdU) and its position was further determined in the plutei larvas by immunofluorescence. We have found that the CS histone variants were segregated to specific territories in the plutei. The position in which the CS histone variants were found to be segregated was consistent with the position in which the DNA molecules that were replicated during the initial cleavage divisions were localized. These results strongly suggest that a specification of embryonic nuclei occurs at the initial cleavage divisions which is determined by a chromatin organized by CS histone variants.


Assuntos
Histonas/biossíntese , Ouriços-do-Mar/fisiologia , Animais , Blástula/metabolismo , Western Blotting , Bromodesoxiuridina , DNA/análise , DNA/biossíntese , Fertilização , Variação Genética , Histonas/análise , Histonas/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Microscopia de Fluorescência , Fatores de Tempo
16.
Santiago de Chile; s.n; 2000. 87 p. tab, graf.
Tese em Espanhol | LILACS | ID: lil-284699

RESUMO

Socialmente, se ha asignado a la mujer el papel exclusivo en la alimentación infantil; hoy se considera fundamental la presencia del padre en este desarrollo, es por eso que no basta considerarlo como el sustento económico familiar sino que también como agente importante en la vinculación del niño con su medio.El propósito de este estudio es describir al padre como agente de fomento y protección de la lactancia. La muestra consta de 40 padres que trabajan en una industria de alimentos de Santiago. La información fue recolectada durante Noviembre y Diciembre de 1999.La literatura muestra que en general los padres opinan que la LM reafirma el vínculo entre la familia; interfiere con las actividades sexuales en la pareja y que no siempre permite su participación. Los resultados muestran que se trata de un grupo de padres en edad madura (45.5 por ciento), con un nivel educacional que facilita la comprensión de instancias educativas. La mayoría de los padres inició su proceso de vinculación con el hijo antes del nacimiento y se incorpora de manera espontánea en la lactancia. Es tarea de los profesionales de la salud facilitar su inserción al binomio madre-hijo y fortalecer el núcleo familiar


Assuntos
Humanos , Masculino , Adulto , Aleitamento Materno/psicologia , Promoção da Saúde/métodos , Desenvolvimento Infantil/fisiologia , Educação em Saúde/métodos , Enfermagem/métodos , Pai/educação , Conhecimentos, Atitudes e Prática em Saúde
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