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1.
Med Mycol ; 58(2): 240-247, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100152

RESUMO

Dual specificity LAMMER kinase has been reported to be conserved across species ranging from yeasts to animals and has multiple functions. Candida albicans undergoes dimorphic switching between yeast cells and hyphal growth forms as its key virulence factors. Deletion of KNS1, which encodes for LAMMER kinase in C. albicans, led to pseudohyphal growth on YPD media and defects in filamentous growth both on spider and YPD solid media containing 10% serum. These cells exhibited expanded central wrinkled regions and specifically reduced peripheral filaments. Among the several stresses tested, the kns1Δ strains showed sensitivity to cell-wall and DNA-replicative stress. Under fluorescent microscopy, an increase in chitin decomposition was observed near the bud necks and septa in kns1Δ cells. When the expression levels of genes for cell wall integrity (CWI) and the DNA repair mechanism were tested, the kns1 double-deletion cells showed abnormal patterns compared to wild-type cells; The transcript levels of genes for glycosylphosphatidylinositol (GPI)-anchored proteins were increased upon calcofluor white (CFW) treatment. Under DNA replicative stress, the expression of MluI-cell cycle box binding factor (MBF)-targeted genes, which are expressed during the G1/S transition in the cell cycle, was not increased in the kns1 double-deletion cells. This strain showed increased adhesion to the surface of an agar plate and zebrafish embryo. These results demonstrate that Kns1 is involved in dimorphic transition, cell wall integrity, response to DNA replicative stress, and adherence to the host cell surface in C. albicans.


Assuntos
Candida albicans/enzimologia , Candida albicans/fisiologia , Dano ao DNA , Proteínas Fúngicas/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Benzenossulfonatos/farmacologia , Candida albicans/efeitos dos fármacos , Ciclo Celular , Parede Celular/fisiologia , DNA Fúngico , Deleção de Genes , Hifas/crescimento & desenvolvimento , Estresse Fisiológico
2.
J Korean Med Sci ; 35(15): e101, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32301293

RESUMO

BACKGROUND: Despite the increasing importance of rehabilitation for critically ill patients, there is little information regarding how rehabilitation therapy is utilized in clinical practice. Our objectives were to evaluate the implementation rate of rehabilitation therapy in the intensive care unit (ICU) survivors and to investigate the effects of rehabilitation therapy on outcomes. METHODS: A retrospective nationwide cohort study with including > 18 years of ages admitted to ICU between January 2008 and May 2015 (n = 1,465,776). The analyzed outcomes were readmission to ICU readmission and emergency room (ER) visit. RESULTS: During the study period, 249,918 (17.1%) patients received rehabilitation therapy. The percentage of patients receiving any rehabilitation therapy increased annually from 14% in 2008 to 20% in 2014, and the percentages for each type of therapy also increased over time. The most common type of rehabilitation was physical therapy (91.9%), followed by neuromuscular electrical stimulation (29.6%), occupational (28.6%), respiratory, (11.6%) and swallowing (10.3%) therapies. After adjusting for confounding variables, the risk of 30-day ICU readmission was lower in patients who received rehabilitation therapy than in those who did not (P < 0.001; hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.65-0.75). And, the risk of 30-day ER visit was also lower in patients who received rehabilitation therapy (P < 0.001; HR, 0.83; 95% CI, 0.77-0.88). CONCLUSION: In this nationwide cohort study in Korea, only 17% of all ICU patients received rehabilitation therapy. However, rehabilitation is associated with a significant reduction in the risk of 30-day ICU readmission and ER visit.


Assuntos
Doenças do Sistema Nervoso Central/reabilitação , Serviços Médicos de Emergência/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Sobreviventes/estatística & dados numéricos , Adulto , Idoso , Doenças do Sistema Nervoso Central/mortalidade , Doenças do Sistema Nervoso Central/patologia , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Modelos de Riscos Proporcionais , República da Coreia , Estudos Retrospectivos
3.
Molecules ; 25(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225092

RESUMO

The novel prenyl transferase-mediated, site-specific, antibody-drug conjugate LCB14-0110 is comprised of a proprietary beta-glucuronide linker and a payload (Monomethyl auristatin F, MMAF, an inhibitor for tubulin polymerization) attached to human epidermal growth factor receptor 2 (HER2)-targeting trastuzumab. A LC-MS/MS method was developed to quantify the antibody-conjugated drug (acDrug) for in vitro linker stability and preclinical pharmacokinetic studies. The method consisted of affinity capture, enzymatic cleavage of acDrug, and LC-MS/MS analysis in the positive ion mode. A quadratic regression (weighted 1/concentration2), with the equation y = ax2 + bx + c, was used to fit calibration curves over the concentration range of 19.17~958.67 ng/mL for acDrug. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. The overall recovery was 42.61%. The dilution integrity was for a series of 5-fold dilutions with accuracy and precision values ranging within ±25%. The stability results indicated that acDrug was stable at all stability test conditions (short-term: 1 day, long-term: 10 months, Freeze/Thaw (F/T): 3 cycles). This qualified method was successfully applied to in vitro linker stability and pharmacokinetic case studies of acDrug in rats.


Assuntos
Cromatografia Líquida , Imunoconjugados/química , Imunoconjugados/farmacocinética , Neopreno , Espectrometria de Massas em Tandem , Transferases , Animais , Monitoramento de Medicamentos , Estabilidade de Medicamentos , Humanos , Estrutura Molecular , Neopreno/química , Ratos , Transferases/química , Trastuzumab/química , Trastuzumab/farmacocinética
4.
J Biol Chem ; 293(34): 13204-13213, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-29970614

RESUMO

The pyruvate dehydrogenase multienzyme complex (PDHc) connects glycolysis to the tricarboxylic acid cycle by producing acetyl-CoA via the decarboxylation of pyruvate. Because of its pivotal role in glucose metabolism, this complex is closely regulated in mammals by reversible phosphorylation, the modulation of which is of interest in treating cancer, diabetes, and obesity. Mutations such as that leading to the αV138M variant in pyruvate dehydrogenase, the pyruvate-decarboxylating PDHc E1 component, can result in PDHc deficiency, an inborn error of metabolism that results in an array of symptoms such as lactic acidosis, progressive cognitive and neuromuscular deficits, and even death in infancy or childhood. Here we present an analysis of two X-ray crystal structures at 2.7-Å resolution, the first of the disease-associated human αV138M E1 variant and the second of human wildtype (WT) E1 with a bound adduct of its coenzyme thiamin diphosphate and the substrate analogue acetylphosphinate. The structures provide support for the role of regulatory loop disorder in E1 inactivation, and the αV138M variant structure also reveals that altered coenzyme binding can result in such disorder even in the absence of phosphorylation. Specifically, both E1 phosphorylation at αSer-264 and the αV138M substitution result in disordered loops that are not optimally oriented or available to efficiently bind the lipoyl domain of PDHc E2. Combined with an analysis of αV138M activity, these results underscore the general connection between regulatory loop disorder and loss of E1 catalytic efficiency.


Assuntos
Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/química , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/metabolismo , Mutação , Doença da Deficiência do Complexo de Piruvato Desidrogenase/genética , Complexo Piruvato Desidrogenase/química , Complexo Piruvato Desidrogenase/metabolismo , Tiamina Pirofosfato/metabolismo , Catálise , Cristalografia por Raios X , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/genética , Humanos , Cinética , Modelos Moleculares , Conformação Proteica , Complexo Piruvato Desidrogenase/genética , Doença da Deficiência do Complexo de Piruvato Desidrogenase/enzimologia
5.
J Psycholinguist Res ; 48(5): 987-1004, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30963377

RESUMO

It is unknown whether linguistic cues influence preschoolers' recognition of facial expression when the emotion of the face is incongruent with the linguistic cues and what type of linguistic cue is influential in the modulation of facial expression. In a priming task, we presented 5-year-old children three types of linguistic information conveying happy or sad emotion (simple label, label with rich causal explanation of emotion, and label with poor causal explanation of emotion) prior to the presentation of a happy or a sad face. We asked participants to recognize emotion of facial expression and examined whether they follow linguistic information than the facial expression when the emotions of linguistic information and face were incongruent. As a result, children who were presented the label with rich causal explanation judged emotion of face according to the linguistic information, whereas children who were presented the simple label or the label with poor causal explanation followed the emotions of facial expression. This result indicated that children's autonomic reliance on situational cues depends on the emotional causality and the concreteness of emotional state conveyed by the linguistic cues. This finding contributes to our understanding of the face inferiority effect on children's developing notion of emotions.


Assuntos
Sinais (Psicologia) , Emoções/fisiologia , Expressão Facial , Linguística , Adulto , Atenção , Desenvolvimento Infantil , Pré-Escolar , Feminino , Humanos , Japão , Masculino , Adulto Jovem
6.
Biotechnol Lett ; 40(3): 509-519, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29302812

RESUMO

OBJECTIVES: To evaluate the effects of dexamethasone on the aging of mesenchymal stem cells from human gingiva using next-generation sequencing. RESULTS: Four mRNAs were upregulated and 12 were downregulated when the results of dexamethasone at 24 h were compared with the control at 24 h. Expressions of SIRT1 and IL6 were decreased in dexamethasone at 24 h but expression of EDN1 was increased. CONCLUSIONS: Application of dexamethasone reduced the expression of SIRT1 and IL6 but enhanced the expression of EDN1 of stem cells.


Assuntos
Dexametasona/farmacologia , Endotelina-1/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-6/metabolismo , Sirtuína 1/metabolismo , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Endotelina-1/análise , Endotelina-1/genética , Perfilação da Expressão Gênica , Gengiva/citologia , Humanos , Interleucina-6/análise , Interleucina-6/genética , Células-Tronco Mesenquimais/citologia , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/análise , Sirtuína 1/genética
7.
EMBO Rep ; 15(7): 809-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24867889

RESUMO

A sequence within the E2 domain of soluble amyloid precursor protein (sAPP) stimulates iron efflux. This activity has been attributed to a ferroxidase activity suggested for this motif. We demonstrate that the stimulation of efflux supported by this peptide and by sAPPα is due to their stabilization of the ferrous iron exporter, ferroportin (Fpn), in the plasma membrane of human brain microvascular endothelial cells (hBMVEC). The peptide does not bind ferric iron explaining why it does not and thermodynamically cannot promote ferrous iron autoxidation. This peptide specifically pulls Fpn down from the plasma membrane of hBMVEC; based on these results, FTP, for ferroportin-targeting peptide, correctly identifies the function of this peptide. The data suggest that in stabilizing Fpn via the targeting due to the FTP sequence, sAPP will increase the flux of iron into the cerebral interstitium. This inference correlates with the observation of significant iron deposition in the amyloid plaques characteristic of Alzheimer's disease.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Células Endoteliais/metabolismo , Ferro/metabolismo , Sequência de Aminoácidos , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/farmacologia , Precursor de Proteína beta-Amiloide/química , Ceruloplasmina/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas
8.
J Phys Ther Sci ; 28(10): 2798-2802, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27821938

RESUMO

[Purpose] The aim of this study was to investigate the association between magnetic resonance imaging (MRI) findings in patients with adhesive shoulder capsulitis and the therapeutic effect of capsular distension. [Subjects and Methods] We retrospectively reviewed the medical records of 57 patients who underwent capsular distension therapy after a diagnosis of adhesive capsulitis with clinical and MRI scans. Axillary joint capsular thickness by MRI was graded as I (≤3.6 mm), II (3.7-4.2 mm), and III (≥4.3 mm). Subcoracoid fat obliteration of the rotator interval was graded subjectively as absent, partial, and complete. [Results] Capsular thickness and fat replacement were correlated with passive range of motion (PROM) and pain score on a visual analog scale (VAS) by analysis of variance with a Bonferroni correction before treatment and by analysis of covariance with a Bonferroni correction after treatment. Visual analog scale (VAS) for patients with all grades decreased significantly after treatment and passive range of motion (PROM) for patients with all grades improved. No difference was detected between grades. [Conclusion] Although MRI is useful to evaluate adhesive capsulitis, MRI findings of shoulder did not predict the prognosis after capsular distension treatment.

9.
Biochemistry ; 54(1): 69-82, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25436986

RESUMO

The human pyruvate dehydrogenase complex (PDC) comprises three principal catalytic components for its mission: E1, E2, and E3. The core of the complex is a strong subcomplex between E2 and an E3-binding protein (E3BP). The PDC is subject to regulation at E1 by serine phosphorylation by four kinases (PDK1-4), an inactivation reversed by the action of two phosphatases (PDP1 and -2). We report H/D exchange mass spectrometric (HDX-MS) and nuclear magnetic resonance (NMR) studies in the first attempt to define the interaction loci between PDK1 and PDK2 with the intact E2·E3BP core and their C-terminally truncated proteins. While the three lipoyl domains (L1 and L2 on E2 and L3 on E3BP) lend themselves to NMR studies and determination of interaction maps with PDK1 and PDK2 at the individual residue level, HDX-MS allowed studies of interaction loci on both partners in the complexes, PDKs, and other regions of the E2·E3BP core, as well, at the peptide level. HDX-MS suggested that the intact E2·E3BP core enhances the binding specificity of L2 for PDK2 over PDK1, while NMR studies detected lipoyl domain residues unique to interaction with PDK1 and PDK2. The E2·E3BP core induced more changes on PDKs than any C-terminally truncated protein, with clear evidence of greater plasticity of PDK1 than of PDK2. The effect of L1L2S paralleled HDX-MS results obtained with the intact E2·E3BP core; hence, L1L2S is an excellent candidate with which to define interaction loci with these two PDKs. Surprisingly, L3S' induced moderate interaction with both PDKs according to both methods.


Assuntos
Medição da Troca de Deutério/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Ligação Proteica/fisiologia , Proteínas Serina-Treonina Quinases/genética , Estrutura Secundária de Proteína , Piruvato Desidrogenase Quinase de Transferência de Acetil , Ratos
10.
J Biol Chem ; 288(21): 15402-17, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23580650

RESUMO

Multifaceted structural approaches were undertaken to investigate interaction of the E2 component with E3 and E1 components from the Escherichia coli pyruvate dehydrogenase multienzyme complex (PDHc), as a representative of the PDHc from Gram-negative bacteria. The crystal structure of E3 at 2.5 Å resolution reveals similarity to other E3 structures and was an important starting point for understanding interaction surfaces between E3 and E2. Biochemical studies revealed that R129E-E2 and R150E-E2 substitutions in the peripheral subunit-binding domain (PSBD) of E2 greatly diminished PDHc activity, affected interactions with E3 and E1 components, and affected reductive acetylation of E2. Because crystal structures are unavailable for any complete E2-containing complexes, peptide-specific hydrogen/deuterium exchange mass spectrometry was used to identify loci of interactions between 3-lipoyl E2 and E3. Two peptides from the PSBD, including Arg-129, and three peptides from E3 displayed statistically significant reductions in deuterium uptake resulting from interaction between E3 and E2. Of the peptides identified on E3, two were from the catalytic site, and the third was from the interface domain, which for all known E3 structures is believed to interact with the PSBD. NMR clearly demonstrates that there is no change in the lipoyl domain structure on complexation with E3. This is the first instance where the entire wild-type E2 component was employed to understand interactions with E3. A model for PSBD-E3 binding was independently constructed and found to be consistent with the importance of Arg-129, as well as revealing other electrostatic interactions likely stabilizing this complex.


Assuntos
Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Complexo Piruvato Desidrogenase/química , Substituição de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/genética , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Espectroscopia de Ressonância Magnética , Mutação de Sentido Incorreto , Estrutura Quaternária de Proteína , Complexo Piruvato Desidrogenase/genética , Complexo Piruvato Desidrogenase/metabolismo
11.
Biochem Biophys Res Commun ; 432(1): 80-5, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23376070

RESUMO

In eukaryotes, LAMMER kinases are involved in various cellular events, including the cell cycle. However, no attempt has been made to investigate the mechanisms that underlie the involvement of LAMMER kinase. In this study, we performed a functional analysis of LAMMER kinase using the fission yeast, Schizosaccharomyces pombe. FACS analyses revealed that deletion of the gene that encodes the LAMMER kinase Lkh1 made mutant cells pass through the G1/S phase faster than their wild-type counterparts. Co-immunoprecipitation and an in vitro kinase assay also revealed that Lkh1 can interact with and phosphorylate Rum1 to activate this molecule as a cyclin-dependent kinase inhibitor, which blocks cell cycle progression from the G1 phase to the S phase. Peptide mass fingerprinting and kinase assay with Rum1(T110A) confirmed T110 as the Lkh1-dependent phosphorylation residue. In this report we present for the first time a positive acting mechanism that is responsible for the CKI activity of Rum1, in which the LAMMER kinase-mediated phosphorylation of Rum1 is involved.


Assuntos
Ciclo Celular/genética , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteínas Quinases/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/citologia , Schizosaccharomyces/enzimologia , Separação Celular , Citometria de Fluxo , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Deleção de Genes , Nitrogênio/deficiência , Fosforilação , Proteínas Quinases/genética , Proteínas de Schizosaccharomyces pombe/genética
12.
J Biol Chem ; 285(18): 13797-806, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20200159

RESUMO

Disruption of the fission yeast LAMMER kinase, Lkh1, gene resulted in diverse phenotypes, including adhesive filamentous growth and oxidative stress sensitivity, but an exact cellular function had not been assigned to Lkh1. Through an in vitro pull-down approach, a transcriptional repressor, Tup12, was identified as an Lkh1 binding partner. Interactions between Lkh1 and Tup11 or Tup12 were confirmed by in vitro and in vivo binding assays. Tup proteins were phosphorylated by Lkh1 in a LAMMER motif-dependent manner. The LAMMER motif was also necessary for substrate recognition in vitro and cellular function in vivo. Transcriptional activity assays using promoters negatively regulated by Tup11 and Tup12 showed 6 or 2 times higher activity in the Delta lkh1 mutant than the wild type, respectively. Northern analysis revealed derepressed expression of the fbp1(+) mRNA in Delta lkh1 and in Delta tup11 Delta tup12 mutant cells under repressed conditions. Delta lkh1 and Delta tup11 Delta tup12 mutant cells showed flocculation, which was reversed by co-expression of Tup11 and -12 with Ssn6. Here, we presented a new aspect of the LAMMER kinase by demonstrating that the activities of global transcriptional repressors, Tup11 and Tup12, were positively regulated by Lkh1-mediated phosphorylation.


Assuntos
Proteínas Quinases/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Motivos de Aminoácidos , Deleção de Genes , Fosforilação/fisiologia , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/fisiologia , Proteínas Quinases/genética , Proteínas Repressoras/genética , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Transcrição Gênica/fisiologia
13.
J Biol Chem ; 285(7): 4680-94, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-19996100

RESUMO

Most bacterial pyruvate dehydrogenase complexes from either gram-positive or gram-negative bacteria have E1 components with an alpha(2) homodimeric quaternary structure. In a sequel to our previous publications, we present the first NMR study on the flexible regions of the E1 component from Escherichia coli and its biological relevance. We report sequence-specific NMR assignments for 6 residues in the N-terminal 1-55 region and for a glycine in each of the two mobile active center loops of the E1 component, a 200-kDa homodimer. This was accomplished by using site-specific substitutions and appropriate labeling patterns along with a peptide with the sequence corresponding to the N-terminal 1-35 amino acids of the E1 component. To study the functions of these mobile regions, we also examined the spectra in the presence of (a) a reaction intermediate analog known to affect the mobility of the active center loops, (b) an E2 component construct consisting of a lipoyl domain and peripheral subunit binding domain, and (c) a peptide corresponding to the amino acid sequence of the E2 peripheral subunit binding domain. Deductions from the NMR studies are in excellent agreement with our functional finding, providing a clear indication that the N-terminal region of the E1 interacts with the E2 peripheral subunit binding domain and that this interaction precedes reductive acetylation. The results provide the first structural support to the notion that the N-terminal region of the E1 component of this entire class of bacterial pyruvate dehydrogenase complexes is responsible for binding the E2 component.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bactérias Gram-Negativas/enzimologia , Espectroscopia de Ressonância Magnética/métodos , Complexo Piruvato Desidrogenase/química , Complexo Piruvato Desidrogenase/metabolismo , Proteínas de Bactérias/genética , Cromatografia em Gel , Ligação Proteica/genética , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/genética , Estrutura Terciária de Proteína/fisiologia , Complexo Piruvato Desidrogenase/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Breast Cancer Res Treat ; 125(1): 99-106, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20922564

RESUMO

To determine whether zoledronic acid (ZA) can prevent bone loss in premenopausal women undergoing adjuvant chemotherapy for breast cancer. In this randomized, open-label, phase III multicenter trial, premenopausal women >40 years were randomly assigned to ZA treatment (4 mg IV, every 6 months) or observation after surgery. All patients were treated with four cycles of AC followed by four cycles of taxane. Between March 2007 and May 2008, we assessed a total of 112 premenopausal women, all of whom developed amenorrhea at 1 year after chemotherapy. The mean percent change of BMD in the lumbar spine (LS) was -1.1% in the ZA group versus -7.5% in observation group at 12 months. Differences in percent change of BMD from baseline between the two groups were 6.4% for the LS, and 3.6% for the femoral neck. The mean levels of bone turnover at 12 months were significantly lower in the ZA group. ZA was generally well tolerated. Infusion of ZA 4 mg every 6 months effectively prevented bone loss within the first year in premenopausal women receiving adjuvant chemotherapy for early breast cancer. Regular BMD measurements and early bisphosphonate therapy should be considered in these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Difosfonatos/administração & dosagem , Colo do Fêmur/efeitos dos fármacos , Imidazóis/administração & dosagem , Vértebras Lombares/efeitos dos fármacos , Osteoporose/prevenção & controle , Absorciometria de Fóton , Amenorreia/induzido quimicamente , Biomarcadores/metabolismo , Conservadores da Densidade Óssea/efeitos adversos , Remodelação Óssea/efeitos dos fármacos , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Difosfonatos/efeitos adversos , Esquema de Medicação , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/metabolismo , Humanos , Imidazóis/efeitos adversos , Infusões Intravenosas , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/metabolismo , Osteoporose/induzido quimicamente , Osteoporose/diagnóstico por imagem , Osteoporose/metabolismo , Pré-Menopausa , Estudos Prospectivos , República da Coreia , Fatores de Tempo , Resultado do Tratamento , Ácido Zoledrônico
15.
Adv Sci (Weinh) ; 8(23): e2102414, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34664433

RESUMO

Human epidermal growth factor receptor 2 (HER2) is overexpressed in breast and gastric cancers and this causes poor clinical outcomes. Although both T-DM1 and Enhertu are approved as an HER2-targeting antibody-drug conjugate (ADC), the effects of these drugs are still not satisfactory to eradicate diverse tumors expressing HER2. To address this shortfall in HER2-targeted therapeutics, an elaborate cleavable linker is created and a novel HER2-targeting ADC composed with trastuzumab and monomethyl auristatin F, which is being investigated in a phase 1 clinical trial and is referred to as LegoChem Bisciences-ADC (LCB-ADC). LCB-ADC displays a higher cytotoxic potency than T-DM1 and it also has a higher G2/M arrest ratio. In animal studies, LCB-ADC produces noticeable tumor growth inhibition compared with trastuzumab or T-DM1 in an HER2 high-expressing N87 xenograft tumor. Especially, LCB-ADC shows good efficacy in terms of suppressing tumor growth in a patient-derived xenograft (PDX) model of HER2-positive gastric cancer as well as in T-DM1-resistant models such as HER2 low-expressing HER2 low expressing JIMT-1 xenograft tumor and PDX. Collectively, the results demonstrate that LCB-ADC with the elaborate linker has a higher efficacy and greater biostability than its ADC counterparts and may successfully treat cancers that are nonresponsive to previous therapeutics.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Imunoconjugados/uso terapêutico , Oligopeptídeos/uso terapêutico , Receptor ErbB-2/genética , Neoplasias Gástricas/tratamento farmacológico , Trastuzumab/uso terapêutico , Animais , Modelos Animais de Doenças , Haplorrinos , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Ratos , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia
16.
Biochemistry ; 49(8): 1616-27, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20078138

RESUMO

Mycobacterium tuberculosis (Mtb) remains the leading single cause of death from bacterial infection. Here we explored the possibility of species-selective inhibition of lipoamide dehydrogenase (Lpd), an enzyme central to Mtb's intermediary metabolism and antioxidant defense. High-throughput screening of combinatorial chemical libraries identified triazaspirodimethoxybenzoyls as high-nanomolar inhibitors of Mtb's Lpd that were noncompetitive versus NADH, NAD(+), and lipoamide and >100-fold selective compared to human Lpd. Efficacy required the dimethoxy and dichlorophenyl groups. The structure of an Lpd-inhibitor complex was resolved to 2.42 A by X-ray crystallography, revealing that the inhibitor occupied a pocket adjacent to the Lpd NADH/NAD(+) binding site. The inhibitor did not overlap with the adenosine moiety of NADH/NAD(+) but did overlap with positions predicted to bind the nicotinamide rings in NADH and NAD(+) complexes. The dimethoxy ring occupied a deep pocket adjacent to the FAD flavin ring where it would block coordination of the NADH nicotinamide ring, while the dichlorophenyl group occupied a more exposed pocket predicted to coordinate the NAD(+) nicotinamide. Several residues that are not conserved between the bacterial enzyme and its human homologue were predicted to contribute both to inhibitor binding and to species selectivity, as confirmed for three residues by analysis of the corresponding mutant Mtb Lpd proteins. Thus, nonconservation of residues lining the electron-transfer tunnel in Mtb Lpd can be exploited for development of species-selective Lpd inhibitors.


Assuntos
Antituberculosos/química , Antituberculosos/metabolismo , Di-Hidrolipoamida Desidrogenase/antagonistas & inibidores , Di-Hidrolipoamida Desidrogenase/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Mycobacterium tuberculosis/enzimologia , Animais , Antituberculosos/efeitos adversos , Antituberculosos/farmacologia , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cristalografia por Raios X , Di-Hidrolipoamida Desidrogenase/química , Di-Hidrolipoamida Desidrogenase/genética , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacologia , Macrófagos/citologia , Camundongos , Modelos Biológicos , Estrutura Molecular , Mutagênese Sítio-Dirigida , NAD/química , NAD/metabolismo , Relação Estrutura-Atividade , Ácido Tióctico/análogos & derivados , Ácido Tióctico/química , Ácido Tióctico/metabolismo
17.
Biochem Biophys Res Commun ; 395(3): 416-9, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20385101

RESUMO

Unlike pyruvate dehydrogenase complexes (PDCs) from prokaryotes, PDCs from higher eukaryotes have an additional structural component, E3-binding protein (BP), for binding of dihydrolipoamide dehydrogenase (E3) in the complex. Based on the 3D structure of the subcomplex of human (h) E3 with the di-domain (L3S1) of hBP, the amino acid residues (H348, D413, Y438, and R447) of hE3 for binding to hBP were substituted singly by alanine or other residues. These substitutions did not have large effects on hE3 activity when measured in its free form. However, when these hE3 mutants were reconstituted in the complex, the PDC activity was significantly reduced to 9% for Y438A, 20% for Y438H, and 18% for D413A. The binding of hE3 mutants with L3S1 determined by isothermal titration calorimetry revealed that the binding affinities of the Y438A, Y438H, and D413A mutants to L3S1 were severely reduced (1019-, 607-, and 402-fold, respectively). Unlike wild-type hE3 the binding of the Y438A mutant to L3S1 was accompanied by an unfavorable enthalpy change and a large positive entropy change. These results indicate that hE3-Y438 and hE3-D413 play important roles in binding of hE3 to hBP.


Assuntos
Di-Hidrolipoamida Desidrogenase/química , Complexo Piruvato Desidrogenase/química , Calorimetria , Di-Hidrolipoamida Desidrogenase/genética , Entropia , Humanos , Cinética , Ligação Proteica , Complexo Piruvato Desidrogenase/genética
18.
Appl Environ Microbiol ; 76(15): 5199-206, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20525861

RESUMO

In this study, the carotenoid biosynthetic pathways of Brevibacterium linens DSMZ 20426 were reconstructed, redesigned, and extended with additional carotenoid-modifying enzymes of other sources in a heterologous host Escherichia coli. The modular lycopene pathway synthesized an unexpected carotenoid structure, 3,4-didehydrolycopene, as well as lycopene. Extension of the novel 3,4-didehydrolycopene pathway with the mutant Pantoea lycopene cyclase CrtY(2) and the Rhodobacter spheroidene monooxygenase CrtA generated monocyclic torulene and acyclic oxocarotenoids, respectively. The reconstructed beta-carotene pathway synthesized an unexpected 7,8-dihydro-beta-carotene in addition to beta-carotene. Extension of the beta-carotene pathway with the B. linens beta-ring desaturase CrtU and Pantoea beta-carotene hydroxylase CrtZ generated asymmetric carotenoid agelaxanthin A, which had one aromatic ring at the one end of carotene backbone and one hydroxyl group at the other end, as well as aromatic carotenoid isorenieratene and dihydroxy carotenoid zeaxanthin. These results demonstrate that reconstruction of the biosynthetic pathways and extension with promiscuous enzymes in a heterologous host holds promise as a rational strategy for generating structurally diverse compounds that are hardly accessible in nature.


Assuntos
Vias Biossintéticas/genética , Brevibacterium/enzimologia , Brevibacterium/genética , Carotenoides/biossíntese , Microbiologia Industrial/métodos , Brevibacterium/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Genética , Genética Microbiana , Pantoea/enzimologia , Pantoea/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Recombinação Genética , Rhodobacter/enzimologia , Rhodobacter/genética
19.
Sci Rep ; 10(1): 5586, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221392

RESUMO

The first member of the velvet family of proteins, VeA, regulates sexual development and secondary metabolism in the filamentous fungus Aspergillus nidulans. In our study, through comparative proteome analysis using wild type and veA-deletion strains, new putative regulators of sexual development were identified and functionally analyzed. Among these, SvfA, containing a yeast survival factor 1 domain, plays multiple roles in the growth and differentiation of A. nidulans. Deletion of the svfA gene resulted in increased sensitivity to oxidative and cold stress as in yeast. The svfA-deletion strain showed an increase in bi-polar germination and a decrease in radial growth rate. The deletion strain formed structurally abnormal conidiophores and thus produced lower amounts of conidiospores during asexual development. The svfA-deletion strain produced few Hülle cells and small cleistothecia with no ascospores, indicating the requirement of svfA for the completion of sexual development. Transcription and genetic analyses indicated that SvfA modulates the expression of key development regulatory genes. Western blot analysis revealed two forms of SvfA. The larger form showed sexual-specific and VeA-dependent production. Also, the deletion of svfA caused decreased ST (sterigmatocystin) production. We propose that SvfA is a novel central regulator of growth, differentiation and secondary metabolism in A. nidulans.


Assuntos
Aspergillus nidulans/crescimento & desenvolvimento , Proteínas Fúngicas/fisiologia , Aspergillus nidulans/genética , Western Blotting , Regulação Fúngica da Expressão Gênica/genética , Reprodução , Esporos Fúngicos/crescimento & desenvolvimento
20.
Transplant Proc ; 52(10): 3002-3008, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32605773

RESUMO

PURPOSE: The purpose of this study was to determine the relationship between pre-operative donor split renal function (SRF) and the renal function outcome of donors and recipients after kidney transplantation (KT). METHODS: A total of 217 living KT cases were investigated. The estimated glomerular filtration rate (eGFR) change of recipients and donors, as well as graft survival, were analyzed based on the donor SRF. The difference in SRF (dSRF) in a donor was defined as follows: the SRF of the donated kidney minus the SRF of the remaining kidney determined by pre-operative 99mTc-diethylenetriaminepentaacetic acid in the donors. The dSRF was categorized into tertiles. RESULTS: The dSRF was not associated with the eGFR in recipients in any tertile at 6 or 12 months post-KT. The overall graft and patient survival did not differ significantly among tertiles. Donors in the high tertile, who donated kidneys with a higher SRF, showed a greater reduction in eGFR than did donors in the low and middle tertile after adjustment for function of the not-donated kidney (-34 ± 1.9 vs -28 ± 2.2, and -27 ± 1.3 mL/min/1.73 m2, P < .05). CONCLUSIONS: The dSRF did not affect the post-KT renal function or graft survival in recipients. However, the donors who donated the better functioning kidney had a poorer renal function after donation.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Transplante de Rim , Rim/fisiopatologia , Doadores Vivos , Adulto , Feminino , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , República da Coreia , Estudos Retrospectivos
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