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1.
Clin Exp Allergy ; 45(7): 1201-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25823600

RESUMO

BACKGROUND: Only limited evidence is available regarding the cytokine repertoire of effector T cells associated with peanut allergy, and how these responses relate to IgE antibodies to peanut components. OBJECTIVE: To interrogate T cell effector cytokine populations induced by Ara h 1 and Ara h 2 among peanut allergic (PA) children in the context of IgE and to evaluate their modulation during oral immunotherapy (OIT). METHODS: Peanut-reactive effector T cells were analysed in conjunction with specific IgE profiles in PA children using intracellular staining and multiplex assay. Cytokine-expressing T cell subpopulations were visualized using SPICE. RESULTS: Ara h 2 dominated the antibody response to peanut as judged by prevalence and quantity among a cohort of children with IgE to peanut. High IgE (> 15 kU(A)/L) was almost exclusively associated with dual sensitization to Ara h 1 and Ara h 2 and was age independent. Among PA children, IL-4-biased responses to both major allergens were induced, regardless of whether IgE antibodies to Ara h 1 were present. Among subjects receiving OIT in whom high IgE was maintained, Th2 reactivity to peanut components persisted despite clinical desensitization and modulation of allergen-specific immune parameters including augmented specific IgG4 antibodies, Th1 skewing and enhanced IL-10. The complexity of cytokine-positive subpopulations within peanut-reactive IL-4(+) and IFN-γ(+) T cells was similar to that observed in those who received no OIT, but was modified with extended therapy. Nonetheless, high Foxp3 expression was a distinguishing feature of peanut-reactive IL-4(+) T cells irrespective of OIT, and a correlate of their ability to secrete type 2 cytokines. CONCLUSION: Although total numbers of peanut-reactive IL-4(+) and IFN-γ(+) T cells are modulated by OIT in highly allergic children, complex T cell populations with pathogenic potential persist in the presence of recognized immune markers of successful immunotherapy.


Assuntos
Citocinas/biossíntese , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Albuminas 2S de Plantas/imunologia , Administração Oral , Adolescente , Alérgenos/administração & dosagem , Alérgenos/imunologia , Antígenos de Plantas/administração & dosagem , Antígenos de Plantas/imunologia , Criança , Pré-Escolar , Dessensibilização Imunológica , Feminino , Glicoproteínas/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunofenotipagem , Lactente , Interleucina-4/biossíntese , Masculino , Hipersensibilidade a Amendoim/terapia
2.
Clin Exp Allergy ; 44(10): 1266-73, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25113532

RESUMO

BACKGROUND: Rhinovirus and IgE act in concert to promote asthma exacerbations. While basophils are the principal cell type in the blood that is activated by IgE, their role in virus-induced asthma episodes remains elusive. OBJECTIVE: To monitor IgE responsiveness in circulating basophils of rhinovirus-infected atopic asthmatics during acute infection and convalescence. METHODS: The capacity for basophils to respond to IgE was assessed by testing the effects of allergen, or cross-linking anti-FcεRI and anti-IgE antibodies, on surface TSLP receptor in 24-hour PBMC cultures. Activation profiles of basophils from atopic asthmatics challenged intranasally with human rhinovirus 16 were monitored directly ex vivo or else in 24-hour cultures, at baseline (day 0), and then at days 4 and 21 post-challenge. RESULTS: Basophils in atopic asthmatics, but not in non-atopic controls, upregulated TSLP receptor upon IgE receptor ligation. The magnitude of this response was correlated with the proportion of serum total IgE that was allergen-specific (r = 0.615, P < 0.05). Following rhinovirus infection, all subjects developed nasal symptoms that peaked 3-5 days after viral challenge. Basophils displayed maximal IgE responsiveness 3 weeks post-challenge as judged by TSLP receptor levels in 24-hour cultures. No significant change in total IgE or specific IgE antibodies was detected during rhinovirus infection. By contrast, levels of IgE receptor-associated spleen tyrosine kinase, Syk, were increased on day 4 (P < 0.05), and elevated levels were also detected three weeks post-challenge. CONCLUSIONS AND CLINICAL RELEVANCE: Circulating basophils display increased IgE responsiveness 3 weeks after rhinovirus infection in atopic asthmatics. This observation, coupled with increased expression of Syk, implicates basophils in promoting, or else prolonging, rhinovirus-induced inflammation in atopic asthmatics.


Assuntos
Asma/imunologia , Basófilos/imunologia , Imunoglobulina E/sangue , Infecções por Picornaviridae/imunologia , Rhinovirus/imunologia , Adolescente , Adulto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/análise , Pessoa de Meia-Idade , Proteínas Tirosina Quinases/análise , Receptores de Citocinas/análise , Quinase Syk , Tetraspanina 30/análise
3.
Clin Exp Allergy ; 43(2): 164-76, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23331558

RESUMO

The prevalence of atopy and allergic disease continues to escalate worldwide. Defining immune mechanisms that suppress the underlying Th2-driven inflammatory process is critical for the rational design of new treatments to prevent or attenuate disease. Allergen immunotherapy has provided a useful framework for evaluating changes in the immune response that occur during the development of tolerance. Despite this, elucidating the phenotypic and functional properties of regulatory cells, has proven challenging in humans with allergic disease. This article provides an overview of our current understanding of the immune pathways that orchestrate allergen tolerance, with an emphasis on emerging concepts related to human disease. A variety of regulatory cell types, including IL-10-secreting T and B cells, play a pivotal role in suppressing allergic responses to inhaled, ingested and injected allergens. These cells may inhibit Th2 effectors directly, or else indirectly, through other cell types and mediators. Protective antibodies, including IgG4, Fc sialylated IgG, and IgA, have the capacity to modulate the response by preventing allergen binding to surface-bound IgE, or inhibiting dendritic cell maturation. Immune cell plasticity may augment suppression of Th2 cells by T regulatory cells, through mechanisms that involve T cell conversion, or else unconventional roles of classical effector cells. These actions depend upon external cues provided by the in vivo milieu. As such, specific anatomical sites may preferentially favour tolerance induction. Recent scientific advances now allow a global analysis of immune parameters that capture novel markers of tolerance induction in allergic patients. Such markers could provide new molecular targets for assessing tolerance, and for designing treatments that confer long-lasting protection in a safe and efficacious fashion.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Tolerância Imunológica/imunologia , Animais , Anticorpos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/metabolismo , Humanos , Interleucina-10/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
4.
Clin Exp Allergy ; 43(10): 1160-70, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24074334

RESUMO

BACKGROUND: Atopic dermatitis (AD) is common in children; however, persistence of AD with or without asthma is less common. Longitudinal studies remain limited in their ability to characterize how IgE antibody responses evolve in AD, and their relationship with asthma. OBJECTIVE: To use a cross-sectional study design of children with active AD to analyse age-related differences in IgE antibodies and relation to wheeze. METHODS: IgE antibodies to food and inhalant allergens were measured in children with active AD (5 months to 15 years of age, n = 66), with and without history of wheeze. RESULTS: Whereas IgE antibodies to foods persisted at a similar prevalence and titre throughout childhood, IgE antibodies to all aeroallergens rose sharply into adolescence. From birth, the chance of sensitization for any aeroallergen increased for each 12-month increment in age (OR ≥ 1.21, P < 0.01), with the largest effect observed for dust mite (OR = 1.56, P < 0.001). A steeper age-related rise in IgE antibody titre to dust mite, but no other allergen was associated with more severe disease. Despite this, sensitization to cat was more strongly associated with wheeze (OR = 4.5, P < 0.01), and linked to Fel d 1 and Fel d 4, but not Fel d 2. Comparison of cat allergic children with AD to those without, revealed higher IgE levels to Fel d 2 and Fel d 4 (P < 0.05), but not Fel d 1. CONCLUSIONS AND CLINICAL RELEVANCE: Differences in sensitization to cat and dust mite among young children with AD may aid in identifying those at increased risk for disease progression and development of asthma. Early sensitization to cat and risk for wheeze among children with AD may be linked to an increased risk for sensitization to a broader spectrum of allergen components from early life. Collectively, our findings argue for early intervention strategies designed to mitigate skin inflammation in children with AD.


Assuntos
Alérgenos/imunologia , Dermatite Atópica/imunologia , Alimentos/efeitos adversos , Sons Respiratórios/imunologia , Adolescente , Fatores Etários , Animais , Especificidade de Anticorpos/imunologia , Gatos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Glicoproteínas/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Lactente , Lipocalinas , Masculino , Razão de Chances , Prognóstico
5.
J Physiol Pharmacol ; 71(4)2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33214340

RESUMO

Fibrin cross-linking by coagulation factor (F)XIII leads to clot stabilization. Reduced plasma FXIII levels have been reported in acute pulmonary embolism (PE) patients. We investigated the impact of anticoagulant therapy on clot-bound amounts of FXIII and α2-antiplasmin and their associations with fibrin clot properties in patients with PE. Clots generated from plasma of 18 acute symptomatic patients on admission and after a 3-month treatment with rivaroxaban were assessed off anticoagulation using mass spectrometry. Plasma FXIII and α2-antiplasmin activity were determined at the 2 time points along with thrombin generation markers, plasma fibrin clot permeability (Ks), and clot lysis time (CLT). Following anticoagulant therapy, clot-bound FXIII increased from 2.97 (interquartile range, 1.98 - 4.08) to 4.66 (3.5 - 6.9) mg/g protein and α2-antiplasmin from 9.4 (7.2 - 10.6) to 11 (9.5 - 14) mg/g protein (both p < 0.0001). The two parameters showed positive correlation at baseline only (r = 0.63, p = 0.0056). Similarly to clot-bound amounts, plasma FXIII (+25.8%) and α2-antiplasmin activity (+12%) increased at 3 months. Plasma FXIII activity on admission, but not after 3 months since the index PE, was associated with amounts of clot-bound FXIII (r = 0.35, p = 0.043) and α2-antiplasmin (r = 0.47, p = 0.048). At baseline, clot-bound FXIII correlated with plasma F1+2 prothrombin fragments levels (r = 0.51, p = 0.03), while clot-bound α2-antiplasmin correlated with CLT (r = 0.43, p = 0.036). At 3 months associations of clot-bound FXIII and α2-antiplasmin were abolished. This study assessed for the first time changes in the fibrin clot composition following acute PE, suggesting an increase of clot-bound and plasma FXIII and α2-antiplasmin levels after 3 months.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Fator XIII/metabolismo , Inibidores do Fator Xa/uso terapêutico , Fibrina/metabolismo , Embolia Pulmonar/tratamento farmacológico , Rivaroxabana/uso terapêutico , alfa 2-Antiplasmina/metabolismo , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/sangue , Embolia Pulmonar/diagnóstico , Fatores de Tempo , Resultado do Tratamento
6.
Science ; 259(5092): 230-4, 1993 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-8421783

RESUMO

The human and Drosophila heat shock transcription factors (HSFs) are multi-zipper proteins with high-affinity binding to DNA that is regulated by heat shock-induced trimerization. Formation of HSF trimers is dependent on hydrophobic heptad repeats located in the amino-terminal region of the protein. Two subregions at the carboxyl-terminal end of human HSF1 were identified that maintain the monomeric form of the protein under normal conditions. One of these contains a leucine zipper motif that is conserved between vertebrate and insect HSFs. These results suggest that the carboxyl-terminal zipper may suppress formation of trimers by the amino-terminal HSF zipper elements by means of intramolecular coiled-coil interactions that are sensitive to heat shock.


Assuntos
Proteínas de Choque Térmico/química , Zíper de Leucina , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , DNA/metabolismo , Drosophila/química , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Temperatura Alta , Humanos , Substâncias Macromoleculares , Dados de Sequência Molecular , Mutagênese , Relação Estrutura-Atividade , Transfecção
7.
Science ; 263(5144): 185-90, 1994 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-17839174

RESUMO

Forest systems cover more than 4.1 x 10(9) hectares of the Earth's land area. Globally, forest vegetation and soils contain about 1146 petagrams of carbon, with approximately 37 percent of this carbon in low-latitude forests, 14 percent in mid-latitudes, and 49 percent at high latitudes. Over two-thirds of the carbon in forest ecosystems is contained in soils and associated peat deposits. In 1990, deforestation in the low latitudes emitted 1.6 +/- 0.4 petagrams of carbon per year, whereas forest area expansion and growth in mid- and high-latitude forest sequestered 0.7 +/- 0.2 petagrams of carbon per year, for a net flux to the atmosphere of 0.9 +/- 0.4 petagrams of carbon per year. Slowing deforestation, combined with an increase in forestation and other management measures to improve forest ecosystem productivity, could conserve or sequester significant quantities of carbon. Future forest carbon cycling trends attributable to losses and regrowth associated with global climate and land-use change are uncertain. Model projections and some results suggest that forests could be carbon sinks or sources in the future.

8.
Adv Biol Regul ; 69: 35-42, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29958836

RESUMO

Glycogen synthase kinase-3 (GSK-3) is a constitutively active kinase, involved in regulation of multiple physiological processes. In brain, changes in GSK-3 signaling are related to neurodegenerative issues, including Alzheimer's disease. Due to the wide range of GSK-3 cellular targets, a therapeutic use of the enzyme inhibitors entails significant risk of side effects. Thus, altering the ratio of specific pool of GSK-3 or specific substrates instead of changing the global activity of GSK-3 in brains might be a more appropriate strategy. This paper provides a comprehensive data on abundances of proteins involved in GSK-3 signaling in three regions of young and old mouse brains. It might help to identify novel protein targets with the highest therapeutic potential for treatment of age-related neurodegenerative diseases.


Assuntos
Envelhecimento/fisiologia , Encéfalo/metabolismo , Cerebelo/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Hipocampo/metabolismo , Camundongos , Proteoma/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Transplant Proc ; 50(1): 155-159, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29407301

RESUMO

BACKGROUND: Hypertension is a very common complication in renal transplant recipients (RTRs). It has been identified as a potent cardiovascular risk factor associated with impaired patient and graft survival. METHODS: A longitudinal retrospective analysis was performed to evaluate adherence to recommended blood pressure (BP) targets and to estimate the tendency in the management of hypertension from 2001 to 2015. A total of 96 RTRs (55 male, 41 female; overall mean age (2001), 41.66 ± 11.08 years; mean serum creatinine level, 1.45 ± 0.3 mg/dL; 41.2 ± 34.9 months after kidney transplantation) with diagnoses of hypertension and monitored continuously in the unit from 2001 to 2015 were included in the study. RESULTS: The average diastolic BP decreased (P < .01) and the average systolic BP did not change in this period. The target values of BP (ie, <140/90 mm Hg) were accomplished by 45.8% (2001) and 53.1% (2015) of patients. When the target BP was corrected by age (<150/90 mm Hg for people >65 years old) the adherence improved to 57.29% in 2015. The average number of antihypertensive agents used per patient increased significantly (P < .001): 2.03 ± 1.0 (2001) versus 2.69 ± 1.26 (2015). The most commonly used antihypertensive agents were beta-blockers: 69% and 74% in 2001 and 2015, respectively. There was a significant increase in the percentage of RTRs treated with the use of alpha-blockers (P < .01), angiotensin-converting enzyme inhibitors (P < .001), and angiotensin II receptor blockers (P < .05). CONCLUSIONS: The study showed modest improvement of the hypertension control rate from 2001 to 2015 in RTRs. Greater efforts are needed to implement the guidelines, which would further improve patient and graft outcomes.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Transplante de Rim/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Adulto , Idoso , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Creatinina/sangue , Feminino , Sobrevivência de Enxerto , Humanos , Hipertensão/etiologia , Hipertensão/fisiopatologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos
10.
Transplant Proc ; 50(6): 1842-1846, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30056912

RESUMO

Angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are the cornerstone treatment in chronic kidney disease patients. Despite facilitating a reduction in blood pressure and albuminuria, there are insufficient data in kidney transplant recipients (KTRs). They are often administered for hypertension and polycythemia treatment. The aim of this study was to investigate the frequency and route of administration of ACEIs and ARBs and their early clinical effects in the KTR population. In a cross-sectional, retrospective study we analyzed 874 medical records of all KTRs treated in our unit in 2014. A total of 391 KTRs (44.7%) using ARBs or ACEIs were qualified for the study. The primary reasons for renin-angiotensin-aldosterone system antagonist administration were hypertension (59.1%), polycythemia (19.2%), and proteinuria (18.2%). Among the studied KTRs, 86.7% of patients were treated with ACEIs and 12.2% were treated with ARBs. The majority of patients treated with ACEIs and ARBs received these agents in a dose range below 25% and between 25% and 49% of their maximal dose, respectively. Both the mean serum creatinine level and estimated glomerular filtration rate (chronic kidney disease epidemiology collaboration) remained fairly stable and urine protein excretion (g/24 hours) was significantly reduced after 3 months of ACEI and ARB therapy. The serum potassium level increased significantly, while hemoglobin concentration dropped significantly. In KTRs, renin-angiotensin-aldosterone system antagonists were applied mainly due to hypertension, proteinuria, and polycythemia. ACEIs and ARBs were effective in the reduction of proteinuria and hemoglobin, but graft function was stable and the increase of serum potassium was not of clinical significance.


Assuntos
Antagonistas de Receptores de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Transplante de Rim , Estudos Transversais , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Policitemia/tratamento farmacológico , Proteinúria/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Estudos Retrospectivos
11.
Mol Cell Biol ; 16(12): 7018-30, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8943357

RESUMO

Heat shock transcription factor (HSF) is a multidomain protein that exists as a monomer under normal conditions and is reversibly induced upon heat shock to a trimeric state that binds to DNA with high affinity. The maintenance of the monomeric state is dependent on hydrophobic heptad repeats located at the amino- and carboxy-terminal regions which have been proposed to form an intramolecular coiled-coil structure. In a systematic deletion analysis to identify other regions of HSF that may be required to regulate its oligomeric state, we have found that local sequences encompassing the carboxy-terminal end of the DNA binding domain and a broad region of HSF between the heptad repeats also contribute to this regulation. Immunocytochemical analysis of mutant HSF proteins revealed a canonical motif required for nuclear localization. HSF proteins lacking the nuclear localization signal remain in the cytoplasm, but these HSFs nonetheless exhibit reversible heat stress-inducible trimerization. The results indicate that the signals that regulate HSF trimerization operate in both the nuclear and cytoplasmic compartments of the cell.


Assuntos
Drosophila/genética , Proteínas de Choque Térmico/genética , Transdução de Sinais/genética , Animais , Transporte Biológico , Núcleo Celular/genética , Mutação
12.
Mol Cell Biol ; 14(10): 6552-60, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7935376

RESUMO

The intracellular level of free heat shock proteins, in particular the 70-kDa stress protein family, has been suggested to be the basis of an autoregulatory mechanism by which the cell measures the level of thermal stress and regulates the synthesis of heat shock proteins. It has been proposed that the DNA-binding and oligomeric state of the heat shock transcription factor (HSF) is a principal step in the induction pathway that is responsive to the level of 70-kDa stress protein. To test this hypothesis, we investigated the association between HSF and 70-kDa stress protein by means of a coimmunoprecipitation assay. We found that 70-kDa stress proteins associate to similar extents with both latent and active forms of HSF, although unlike other 70-kDa stress protein substrates, the association with HSF was not significantly disrupted in the presence of ATP. Gel mobility shift assays indicated that active HSF trimers purified from a bacterial expression system could not be substantially deactivated in vitro with purified 70-kDa stress protein and ATP. In addition, elevated concentrations of hsp70 alone could not significantly inhibit induction of the DNA-binding activity of endogenous HSF in cultured rat cells, and the induction was also not inhibited in cultured rat cells or Drosophila cells containing elevated levels of all members of the heat shock protein family. However, the deactivation of HSF to the non-DNA-binding state after prolonged heat stress or during recovery could be accelerated by increased levels of heat shock proteins. Hence, the level of heat shock proteins may affect the rate of disassembly of HSF trimers, but another mechanism, as yet undefined, appears to control the onset of the oligomeric transitions.


Assuntos
Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Fatores de Transcrição/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Drosophila/citologia , Fatores de Transcrição de Choque Térmico , Temperatura Alta , Humanos , Testes de Precipitina , Ligação Proteica/efeitos dos fármacos , Ratos , Proteínas Recombinantes/metabolismo
13.
Mol Biol Cell ; 10(3): 771-84, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10069817

RESUMO

In many organisms, there are multiple isoforms of cytoplasmic dynein heavy chains, and division of labor among the isoforms would provide a mechanism to regulate dynein function. The targeted disruption of somatic genes in Tetrahymena thermophila presents the opportunity to determine the contributions of individual dynein isoforms in a single cell that expresses multiple dynein heavy chain genes. Substantial portions of two Tetrahymena cytoplasmic dynein heavy chain genes were cloned, and their motor domains were sequenced. Tetrahymena DYH1 encodes the ubiquitous cytoplasmic dynein Dyh1, and DYH2 encodes a second cytoplasmic dynein isoform, Dyh2. The disruption of DYH1, but not DYH2, resulted in cells with two detectable defects: 1) phagocytic activity was inhibited, and 2) the cells failed to distribute their chromosomes correctly during micronuclear mitosis. In contrast, the disruption of DYH2 resulted in a loss of regulation of cell size and cell shape and in the apparent inability of the cells to repair their cortical cytoskeletons. We conclude that the two dyneins perform separate tasks in Tetrahymena.


Assuntos
Citoplasma/metabolismo , Dineínas/genética , Proteínas de Protozoários/genética , Tetrahymena thermophila/genética , Sequência de Aminoácidos , Animais , Segregação de Cromossomos , Citoplasma/química , Citoesqueleto/genética , Citoesqueleto/metabolismo , Dineínas/metabolismo , Técnicas Genéticas , Mitose/genética , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fagocitose/genética , Proteínas de Protozoários/metabolismo , Homologia de Sequência de Aminoácidos
14.
Methods Enzymol ; 585: 15-27, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28109427

RESUMO

Filter-aided sample preparation (FASP) is a versatile and efficient way of processing protein extracts for bottom-up proteomic analysis. The method repurposes centrifugal ultrafiltration concentrators for removal of detergents, protein cleavage, and isolation of pure peptide fractions. FASP can be used for protein cleavage with different proteinases either with single enzymes or in a mode of successive multienzyme digestion (MED)-FASP. The FASP methods are useful for processing of samples ranging in their sizes from submicrogram to several milligram amounts of total protein. They also allow peptide fractionation, and isolation and quantitation of total RNA and DNA acid contents. This chapter describes principles, limitations, and applications of FASP. Additionally detailed FASP and MED-FASP protocols are provided.


Assuntos
Proteômica/métodos , DNA/química , Proteoma/análise , RNA/química
15.
Methods Enzymol ; 585: 49-60, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28109442

RESUMO

Understanding biological systems and their variation upon stimuli requires knowledge on their composition, primarily including information on organization and dynamics of proteomes. The total protein approach (TPA) is a label- and standard-free method for absolute protein quantitation of proteins using large-scale proteomic data. The method relies on the assumption that the total MS signal from all identified proteins in the dataset reflects-in a biochemical sense-the total protein and the MS signal from a single protein corresponds its abundance in the studied sample. The method offers an easy way to quantify thousands of protein per sample. A related method, the "Proteomic Ruler," enables conversion of the protein abundance data calculated by TPA to compute numbers of protein copies per cell. TPA and the Proteomic Ruler are powerful tools for studying dynamics of cell architecture.


Assuntos
Proteínas/metabolismo , Proteômica/métodos , Proteoma/análise
16.
Methods Enzymol ; 585: 159-176, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28109428

RESUMO

Extensive use of biomarkers in diagnostic and therapeutic procedures is probably the hallmark of future medicine. Biomarkers can be of different chemical nature-most frequently DNA, RNA, and proteins are considered as molecules of interest. As the most rational approach appears analysis of proteins, because these are the "effector" molecules directly involved for cell homeostasis. There is no commonly accepted standard procedure in proteomic-based biomarker search. In this chapter, we described a protocol for proteomic analysis of formalin-fixed and paraffin-embedded tissue, which has been proven to be highly effective for proteomics-based biomarker discovery.


Assuntos
Inclusão em Parafina/métodos , Proteômica/métodos , Biomarcadores , DNA/química , Formaldeído , RNA/química
17.
Cochrane Database Syst Rev ; (4): CD005111, 2006 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-17054239

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS), a disorder of altered bowel habits associated with abdominal pain or discomfort. The pain, discomfort, and impairment from IBS often lead to healthcare medical consultation (Talley 1997) and workplace absenteeism, and associated economic costs (Leong 2003). A recent randomized controlled trial shows variable results but no clear evidence in support of acupuncture as an effective treatment for IBS (Fireman 2001). OBJECTIVES: The objective of this systematic review is to determine whether acupuncture is more effective than no treatment, more effective than 'sham' (placebo) acupuncture, and as effective as other interventions used to treat irritable bowel syndrome. Adverse events associated with acupuncture were also assessed. SEARCH STRATEGY: The following electronic bibliographic databases were searched irrespective of language, date of publication, and publication status: MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library, EMBASE, the Chinese Biomedical Database, the Cumulative Index to Nursing and Allied Health (CINAHL), and the Allied and Complementary Medicine Database (AMED). References in relevant reviews and RCTs were screened by hand. The last date for searching for studies was 7 February 2006. SELECTION CRITERIA: Published reports of randomized controlled trials (RCTs) and quasi-randomised trials of acupuncture therapy for IBS. DATA COLLECTION AND ANALYSIS: All eligible records identified were dually evaluated for eligibility and dually abstracted. Methodological quality was assessed using the Jadad scale and the Linde Internal Validity Scale. Data from individual trials were combined for meta-analysis when the interventions were sufficiently similar. Heterogeneity was assessed using the I squared statistic. MAIN RESULTS: Six trials were included. The proportion of responders, as assessed by either the global symptom score or the patient-determined treatment success rate, did not show a significant difference between the acupuncture and the sham acupuncture group with a pooled relative risk of 1.28 (95% CI 0.83 to 1.98; n=109). Acupuncture treatment was also not significantly more effective than sham acupuncture for overall general well-being, individual symptoms (e.g., abdominal pain, defecation difficulties, diarrhea, and bloating), the number of improved patients assessed by blinded clinician, or the EuroQol score. For two of the studies without a sham control, acupuncture was more effective than control treatment for the improvement of symptoms: acupuncture versus herbal medication with a RR of 1.14(95% CI 1.00 to 1.31; n=132); acupuncture plus psychotherapy versus psychotherapy alone with a RR of 1.20 (95% CI 1.03 to 1.39; n=100). When the effect of ear acupuncture treatment was compared to an unclearly specified combination of one or more of the drugs diazepam, perphenazine or domperidone, the difference was not statistically significant with a RR of 1.49(95% CI 0.94 to 2.34; n=48). AUTHORS' CONCLUSIONS: Most of the trials included in this review were of poor quality and were heterogeneous in terms of interventions, controls, and outcomes measured. With the exception of one outcome in common between two trials, data were not combined. Therefore, it is still inconclusive whether acupuncture is more effective than sham acupuncture or other interventions for treating IBS.


Assuntos
Terapia por Acupuntura , Síndrome do Intestino Irritável/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Biochim Biophys Acta ; 1048(1): 93-9, 1990 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-1688714

RESUMO

The isolation of a rat hsp 70-related gene which is specifically and highly expressed in testis is described together with the complete nucleotide sequence of the transcription unit (2947 bp), 5' flanking (about 1 kbp) and 3' flanking (about 0.3 kbp) regions. The sequence analysis and nuclease S1 mapping revealed that the isolated gene (referred to as the hst70 gene) represents a novel, distinct member of the hsp70 multigene family. Its transcription unit lacks introns and a single open reading frame encodes a protein of 69.5 kDa. The predicted amino acid sequence of this protein is highly similar (only four out of 633 amino acids are different) to that encoded by the mouse testis-specific hsp70.2 gene (Zakeri, Z.F., Wolgemuth, D.J. and Hunt, C.R. (1988) Mol. Cell. Biol. 8, 2925-2932). The functional significance of multiple potentially regulatory sequences (e.g. TATA-boxes, heat-shock element and estrogen receptor binding site) present in the 5' flanking region of the rat hst70 gene is discussed.


Assuntos
Proteínas de Choque Térmico/genética , Testículo/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Choque Térmico/isolamento & purificação , Masculino , Dados de Sequência Molecular , RNA/genética , RNA/isolamento & purificação , Ratos , Ratos Endogâmicos , Transcrição Gênica
19.
Biochim Biophys Acta ; 1219(1): 64-72, 1994 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-8086479

RESUMO

In rat cells hyperthermia induces two hsp70 transcripts of 2.5 kb and 2.7 kb. We have cloned and determined the nucleotide sequence of a gene (named hsp70.1) encoding the 2.5 kb transcript as shown by Northern blot analysis using the 5' end and 3' end specific hybridization probes. It contains an uninterrupted open reading frame of 1926 bp, it encodes a protein of approx. 70,100 Da and the predicted amino acid sequence of its product shows 98% similarity to the mouse hsp70.1 protein. The transcription start site was localized 224 bp upstream the ATG codon by RNase protection and primer extension mapping. Upstream the transcription initiation site several potential regulatory motifs including a TATA box, two Sp1 binding sites, one inverted and one direct CCAAT box and three HSEs (heat shock elements) were found. Transfection experiments with constructs in which the CAT reporter gene was fused to fragments of the 5' end flanking sequences of the isolated gene confirmed that the promoter of the rat hsp70.1 gene is functional and heat inducible.


Assuntos
Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Família Multigênica/genética , Albinismo , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Proteínas de Choque Térmico/biossíntese , Hipertermia Induzida , Masculino , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
20.
Biochim Biophys Acta ; 1009(3): 237-43, 1989 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-2480808

RESUMO

The expression pattern of the hsp70 gene family during regeneration or rat liver has been investigated. Northern blots were prepared from total RNA isolated from livers at 0 h (control), 12 h (end of prereplication phase), 24 h (maximum of DNA synthesis) and 36 h (postmitotic phase) after partial hepatectomy. Blots were hybridized with probes specific for the hsp70 (heat-inducible), hsc70 (constitutively expressed), hst70 (testis-specific) and grp78 (glucose-regulated) gene. No hsp70 and hst70 gene transcripts have been detected at any time point investigated, and only a low increase of the hsc70 mRNA level has been observed 24 h after surgery. In contrast, a significant accumulation of the transcript coded by the grp78 gene has been detected in liver remnant 12 and 24 h after partial hepatectomy. However, we observed a comparable activation of this gene in livers of sham-operated rats or in rats injected with turpentine to cause sterile inflammation. Our results indicate that the activation of the grp78 gene in liver of wounded rats (partial hepatectomy or sham operation) is presumably a part of acute-phase response.


Assuntos
Reação de Fase Aguda/genética , Proteínas de Transporte/genética , Regulação da Expressão Gênica , Inflamação/genética , Regeneração Hepática/genética , Chaperonas Moleculares , Animais , Glicemia/análise , Northern Blotting , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cinética , Masculino , Hibridização de Ácido Nucleico , Plasmídeos , RNA/genética , Ratos , Ratos Endogâmicos , Inanição/sangue , Transcrição Gênica
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