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1.
J Thromb Thrombolysis ; 51(3): 818-820, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32728910

RESUMO

Amniotic fluid embolism (AFE) is a catastrophic condition in the peripartum period and still remains as a leading cause of maternal death. Although over 80% of cases of AFE cases are accompanied by coagulopathy, the pathology of disseminated intravascular coagulation is not well understood not only because of its rarity but also because of the limited availability of laboratory testing in emergent clinical settings. We describe a case of AFE whose characteristic data for coagulation and fibrinolysis were timely depicted with sequential thromboelastography. We believe that the point-of-care, which provides information for both coagulopathy and fibrinolysis, may provide crucial data not only for the treatment of postpartum hemorrhage in daily clinical practice but also for the elucidation of AFE pathophysiology.


Assuntos
Coagulação Intravascular Disseminada , Embolia Amniótica , Fibrinólise , Histerectomia/métodos , Complicações do Trabalho de Parto , Hemorragia Pós-Parto , Tromboelastografia/métodos , Adulto , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/complicações , Coagulação Intravascular Disseminada/diagnóstico , Coagulação Intravascular Disseminada/etiologia , Embolia Amniótica/sangue , Embolia Amniótica/diagnóstico , Embolia Amniótica/fisiopatologia , Serviços Médicos de Emergência/métodos , Serviços Médicos de Emergência/organização & administração , Feminino , Humanos , Recém-Nascido , Masculino , Monitorização Fisiológica/métodos , Complicações do Trabalho de Parto/sangue , Complicações do Trabalho de Parto/diagnóstico , Complicações do Trabalho de Parto/fisiopatologia , Complicações do Trabalho de Parto/terapia , Testes Imediatos/organização & administração , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/cirurgia , Gravidez , Resultado da Gravidez , Resultado do Tratamento
2.
Scand J Rheumatol ; 45(5): 412-22, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26901593

RESUMO

OBJECTIVES: The lectin-like oxidized low density lipoprotein (ox-LDL) receptor 1 (LOX-1)/ox-LDL system, which contributes to the pathogenesis of atherosclerosis, may be involved in the development of osteoarthritis (OA). However, the mechanisms by which the LOX-1/ox-LDL system contributes to OA development in vivo are unclear. In this study, we investigated the direct involvement of LOX-1/ox-LDL in OA development by using LOX-1-knockout (LOX-1(-)/(-)) mice in a joint instability-induced model of OA. METHOD: OA development was evaluated with histological scoring at 4 and 8 weeks after surgery to induce knee destabilization in LOX-1(+)/(+) and LOX-1(-)/(-) mice. Immunohistological analysis was used to evaluate the expression of LOX-1, ox-LDL, Runt-related transcription factor 2 (Runx2), and type X collagen (COL X) in articular chondrocytes and osteophyte-forming cells. In addition, double immunofluorescence staining was performed to determine the relationships between LOX-1 and Runx2 or COL X expression. RESULTS: In the model of knee destabilization, symptoms were significantly suppressed in LOX-1(-)/(-) mice. LOX-1, ox-LDL, Runx2, and COL X were overexpressed in articular chondrocytes and osteophyte-forming cells in LOX-1(+)/(+) mice and were significantly downregulated in articular chondrocytes and osteophyte-forming cells in LOX-1(-)/(-) mice compared with those in LOX-1(+)/(+) mice. Double immunostaining indicated that LOX-1 localization coincided with Runx2 and COL X expression. CONCLUSIONS: These data indicate that the LOX-1/ox-LDL system plays a pivotal role in the pathogenesis of instability-induced OA through endochondral ossification. LOX-1-positive chondrocytes and osteophyte-forming cells may be possible targets to prevent disease progression in OA.


Assuntos
Instabilidade Articular , Osteoartrite do Joelho/genética , Receptores Depuradores Classe E/genética , Animais , Artrite Experimental , Condrócitos/metabolismo , Colágeno Tipo X/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Imuno-Histoquímica , Articulação do Joelho , Lipoproteínas LDL/metabolismo , Masculino , Meniscos Tibiais/cirurgia , Camundongos , Camundongos Knockout , Osteoartrite do Joelho/metabolismo , Osteófito , Receptores Depuradores Classe E/metabolismo , Lesões do Menisco Tibial
3.
J Obstet Gynaecol Res ; 42(6): 707-15, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26913817

RESUMO

AIM: The optimal treatment for pelvic organ prolapse has been the subject of much discussion. The aim of this study was to assess the utility of a combination of uterosacral colpopexy and anterior vaginal mesh implantation. METHODS: A single-center prospective cohort study was conducted. Twenty-eight patients with stage III-IV cystocele and uterine prolapse underwent reconstructive surgery. A combination of vaginal hysterectomy, McCall culdeplasty, and trocar-guided anterior vaginal mesh implantation was performed, and the patients' postoperative outcomes were analyzed. Patient satisfaction was investigated using the modified Short Form 12 version 2 (SF-12v2) questionnaire, and interviews regarding sexual behavior were conducted at 1 postoperative year. RESULTS: A bladder injury occurred during the dissection in one case (3.6%). Recurrent vaginal vault prolapse beyond the hymen was observed in one patient (cure rate: 96.4%), and further mesh augmentation was required in this case. Another patient developed mild cystocele (Ba = 0), but was simply observed because she did not complain of any symptoms caused by vaginal descent. We did not experience any other mesh-related complications, such as protrusion, chronic pain, or chronic inflammation, during the follow-up period. The patients' modified SF-12 scores at 12 months were significantly better than their preoperative scores in all eight domains. CONCLUSION: The satisfactory correction of pelvic organ prolapse was achieved using a combination of vaginal hysterectomy and uterosacral ligament colpopexy augmented by anterior vaginal mesh implantation. © 2016 Japan Society of Obstetrics and Gynecology.


Assuntos
Histerectomia Vaginal/métodos , Prolapso de Órgão Pélvico/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Idoso , Cistocele/epidemiologia , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia , Pessoa de Meia-Idade , Satisfação do Paciente , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Resultado do Tratamento
4.
Arch Gynecol Obstet ; 303(5): 1375-1376, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32676858
5.
Ultrasound Obstet Gynecol ; 46(2): 221-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25366537

RESUMO

OBJECTIVE: To investigate time intervals of the ductus venosus (DV) flow velocity waveform (FVW) and those of the cardiac cycle that correspond with each DV-FVW component in fetuses with intrauterine growth restriction (IUGR) due to placental insufficiency. METHODS: Women with a pregnancy complicated by IUGR were recruited into the study, as was a normal control group. Time intervals for systolic (S) and diastolic (D) components were measured in DV-FVW as follows: S(DV), from the nadir of the a-wave during atrial contraction to the nadir between the S-wave and D-wave; D(DV), from the nadir between S-wave and D-wave to the nadir of the a-wave. Regarding cardiac cycles, the following variables were measured from ventricular inflow through the tricuspid valve (TV) and mitral valve (MV): S(TV) and S(MV), from the second peak of ventricular inflow caused by atrial contraction (A-wave) to the opening of the atrioventricular valve; D(TV) and D(MV), from the opening of the atrioventricular valve to the peak of the A-wave. In the IUGR group, only the last examination performed within 1 week of delivery was used for analysis. All variables were analyzed statistically using Z-scores. RESULTS: Data were obtained from 249 normal fetuses and 26 fetuses with IUGR. Compared to normal fetuses, S(DV) showed a significant decrease (P < 0.001), while D(DV) showed a significant increase (P < 0.001) in the IUGR group. Regarding cardiac cycles, S(TV) and S(MV) showed significant decreases (P = 0.014 and P < 0.001, respectively) and D(TV) and D(MV) showed significant increases (P = 0.008 and P = 0.002, respectively) in fetuses with IUGR. CONCLUSION: Time-interval alterations of DV-FVW in growth-restricted fetuses reflect the hemodynamic events caused by placental insufficiency.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Retardo do Crescimento Fetal/fisiopatologia , Coração Fetal/fisiopatologia , Feto/irrigação sanguínea , Insuficiência Placentária/fisiopatologia , Adulto , Ecocardiografia Doppler/métodos , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Coração Fetal/diagnóstico por imagem , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Insuficiência Placentária/diagnóstico por imagem , Gravidez , Estudos Retrospectivos , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiopatologia , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/fisiopatologia , Veias Umbilicais/diagnóstico por imagem , Veias Umbilicais/fisiopatologia
6.
Nat Commun ; 15(1): 3911, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724541

RESUMO

Vibrational spectroscopy allows us to understand complex physical and chemical interactions of molecular crystals and liquids such as ammonia, which has recently emerged as a strong hydrogen fuel candidate to support a sustainable society. We report inelastic neutron scattering measurement of vibrational properties of ammonia along the solid-to-liquid phase transition with high enough resolution for direct comparisons to ab-initio simulations. Theoretical analysis reveals the essential role of nuclear quantum effects (NQEs) for correctly describing the intermolecular spectrum as well as high energy intramolecular N-H stretching modes. This is achieved by training neural network models using ab-initio path-integral molecular dynamics (PIMD) simulations, thereby encompassing large spatiotemporal trajectories required to resolve low energy dynamics while retaining NQEs. Our results not only establish the role of NQEs in ammonia but also provide general computational frameworks to study complex molecular systems with NQEs.

7.
Clin Genet ; 82(5): 425-32, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22575033

RESUMO

Auditory neuropathy is a hearing disorder characterized by normal outer hair cell function and abnormal neural conduction of the auditory pathway. Aetiology and clinical presentation of congenital or early-onset auditory neuropathy are heterogeneous, and their correlations are not well understood. Genetic backgrounds and associated phenotypes of congenital or early-onset auditory neuropathy were investigated by systematically screening a cohort of 23 patients from unrelated Japanese families. Of the 23 patients, 13 (56.5%) had biallelic mutations in OTOF, whereas little or no association was detected with GJB2 or PJVK, respectively. Nine different mutations of OTOF were detected, and seven of them were novel. p.R1939Q, which was previously reported in one family in the United States, was found in 13 of the 23 patients (56.5%), and a founder effect was determined for this mutation. p.R1939Q homozygotes and compound heterozygotes of p.R1939Q and truncating mutations or a putative splice site mutation presented with stable, and severe-to-profound hearing loss with a flat or gently sloping audiogram, whereas patients who had non-truncating mutations except for p.R1939Q presented with moderate hearing loss with a steeply sloping, gently sloping or flat audiogram, or temperature-sensitive auditory neuropathy. These results support the clinical significance of comprehensive mutation screening for auditory neuropathy.


Assuntos
Efeito Fundador , Estudos de Associação Genética/métodos , Perda Auditiva Central/epidemiologia , Perda Auditiva Central/genética , Proteínas de Membrana/genética , Adulto , Sequência de Aminoácidos , Povo Asiático/genética , Criança , Pré-Escolar , Conexina 26 , Conexinas/genética , Conexinas/metabolismo , Feminino , Testes Genéticos , Genótipo , Heterozigoto , Homozigoto , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fenótipo , Prevalência , Conformação Proteica , Análise de Sequência de DNA
8.
Nat Commun ; 13(1): 1213, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260556

RESUMO

V/A-ATPase is a motor protein that shares a common rotary catalytic mechanism with FoF1 ATP synthase. When powered by ATP hydrolysis, the V1 domain rotates the central rotor against the A3B3 hexamer, composed of three catalytic AB dimers adopting different conformations (ABopen, ABsemi, and ABclosed). Here, we report the atomic models of 18 catalytic intermediates of the V1 domain of V/A-ATPase under different reaction conditions, determined by single particle cryo-EM. The models reveal that the rotor does not rotate immediately after binding of ATP to the V1. Instead, three events proceed simultaneously with the 120˚ rotation of the shaft: hydrolysis of ATP in ABsemi, zipper movement in ABopen by the binding ATP, and unzipper movement in ABclosed with release of both ADP and Pi. This indicates the unidirectional rotation of V/A-ATPase by a ratchet-like mechanism owing to ATP hydrolysis in ABsemi, rather than the power stroke model proposed previously for F1-ATPase.


Assuntos
Adenosina Trifosfatases , Trifosfato de Adenosina , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Hidrólise , Modelos Moleculares , ATPases Translocadoras de Prótons/metabolismo , Rotação
9.
Br J Dermatol ; 165(6): 1290-2, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21801157

RESUMO

The palmoplantar keratodermas (PPKs) are a large group of genodermatoses comprising nearly 60 genetically distinct diseases. They are characterized by hyperkeratosis on the palms and soles with or without extrapalmoplantar hyperkeratotic lesions. Focal PPK is one of the hallmarks of pachyonychia congenita, a rare autosomal dominant disorder resulting from mutations in the keratin genes KRT6A, KRT6B, KRT16 or KRT17. Recently, in-frame deletion mutations of KRT6C have been identified in three families with focal PPK with slight or no nail changes. We report here a novel KRT6C mutation identified in a Japanese family with PPK with phenotypic heterogeneity, presenting with not only focal but also diffuse hyperkeratosis. The proband had diffuse hyperkeratosis on the soles and small focal hyperkeratoses on the palms, while the two other affected individuals showed focal hyperkeratoses on the soles. All three patients were heterozygotes for c.1414G>A in KRT6C, predicted to result in p.Glu472Lys. These findings strongly suggest that screening of patients with nonepidermolytic diffuse PPK, in whom the pathogenic mutations are yet to be determined, might identify mutations in KRT6C.


Assuntos
Dermatoses do Pé/genética , Dermatoses da Mão/genética , Queratina-6/genética , Ceratodermia Palmar e Plantar/genética , Mutação/genética , Adulto , Feminino , Heterozigoto , Humanos , Masculino , Linhagem
10.
J Eur Acad Dermatol Venereol ; 25(4): 475-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20569287

RESUMO

BACKGROUND: Topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is widely used for treating Bowen's disease (BD), but recurrence and tumour cell persistence after ALA-PDT is sometimes problematic. Radiation therapy (RT) is also effective for BD, but is limited by its side-effects, such as refractory ulcers. OBJECTIVE: The objective of the study was to observe a synergic effect of combination therapy with ALA-PDT and RT for BD cases that did not respond effectively to prior ALA-PDT. METHODS: Subjects were BD patients whose lesion did not show complete remission or showed recurrence after prior ALA-PDT. A total of four cases involving four lesions were studied (three male and one female, mean age 69.5). ALA ointment (20%) was applied to the lesions. After 4 to 6h, subjects received combination therapy consisting of excimer-pumped dye laser radiation at 630nm (50J/cm(2) ) followed by electron-beam radiation (3Gy). The combination therapy was repeated every 2 to 3days for a total of four treatments. The lesions were evaluated clinically or histologically after the final combination therapy session. RESULTS: Following combination therapy, all of the lesions disappeared. Recurrence was not detected during the observations periods, which averaged 14.0months in duration. CONCLUSION: Our results indicate that the cure rate of BD could be improved by combination therapy with ALA-PDT and RT. Compared with conventional RT, the synergetic effect of this therapy might reduce the dose of radiation required, thereby also reducing skin side-effects such as refractory ulcers.


Assuntos
Doença de Bowen/terapia , Fotoquimioterapia , Idoso , Idoso de 80 Anos ou mais , Doença de Bowen/tratamento farmacológico , Doença de Bowen/radioterapia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Phys Rev Lett ; 105(1): 014503, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20867452

RESUMO

Shock-induced collapse of nanobubbles in water is investigated with molecular dynamics simulations based on a reactive force field. We observe a focused jet at the onset of bubble shrinkage and a secondary shock wave upon bubble collapse. The jet length scales linearly with the nanobubble radius, as observed in experiments on micron-to-millimeter size bubbles. Shock induces dramatic structural changes, including an ice-VII-like structural motif at a particle velocity of 1 km/s. The incipient ice VII formation and the calculated Hugoniot curve are in good agreement with experimental results.

12.
J Cell Biol ; 124(4): 425-34, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8106544

RESUMO

The SAR1 gene product (Sar1p), a 21-kD GTPase, is a key component of the ER-to-Golgi transport in the budding yeast. We previously reported that the in vitro reconstitution of protein transport from the ER to the Golgi was dependent on Sar1p and Sec12p (Oka, T., S. Nishikawa, and A. Nakano. 1991. J. Cell Biol. 114:671-679). Sec12p is an integral membrane protein in the ER and is essential for the Sar1 function. In this paper, we show that Sar1p can remedy the temperature-sensitive defect of the sec12 mutant membranes, which is in the formation of ER-to-Golgi transport vesicles. The addition of Sar1p promotes vesicle formation from the ER irrespective of the GTP- or GTP gamma S-bound form, indicating that the active form of Sar1p but not the hydrolysis of GTP is required for this process. The inhibition of GTP hydrolysis blocks transport of vesicles to the Golgi and thus causes their accumulation. The accumulating vesicles, which carry Sar1p on them, can be separated from other membranes, and, after an appropriate wash that removes Sar1p, are capable of delivering the content to the Golgi when added back to fresh membranes. Thus we have established a new method for isolation of functional intermediate vesicles in the ER-to-Golgi transport. The sec23 mutant is defective in activation of Sar1 GTPase (Yoshihisa, T., C. Barlowe, and R. Schekman. 1993. Science (Wash. DC). 259:1466-1468). The membranes and cytosol from the sec23 mutant show only a partial defect in vesicle formation and this defect is also suppressed by the increase of Sar1p. Again GTP hydrolysis is not needed for the suppression of the defect in vesicle formation. Based on these results, we propose a model in which Sar1p in the GTP-bound form is required for the formation of transport vesicles from the ER and the GTP hydrolysis by Sar1p is essential for entering the next step of vesicular transport to the Golgi apparatus.


Assuntos
Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Monoméricas de Ligação ao GTP , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Transporte Biológico , Proteínas de Ligação ao GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Hidrólise , Cinética , Temperatura , Proteínas de Transporte Vesicular
13.
J Cell Biol ; 109(6 Pt 1): 2677-91, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2512296

RESUMO

SAR1, a gene that has been isolated as a multicopy suppressor of the yeast ER-Golgi transport mutant sec12, encodes a novel GTP-binding protein. Its nucleotide sequence predicts a 21-kD polypeptide that contains amino acid sequences highly homologous to GTP-binding domains of many ras-related proteins. Gene disruption experiments show that SAR1 is essential for cell growth. To test its function further, SAR1 has been placed under control of the GAL1 promoter and introduced into a haploid cell that had its chromosomal SAR1 copy disrupted. This mutant grows normally in galactose medium but arrests growth 12-15 h after transfer to glucose medium. At the same time, mutant cells accumulate ER precursor forms of a secretory pheromone, alpha-mating factor, and a vacuolar enzyme, carboxypeptidase Y. We propose that Sec12p and Sarlp collaborate in directing ER-Golgi protein transport.


Assuntos
Retículo Endoplasmático/metabolismo , Escherichia coli/genética , Proteínas de Ligação ao GTP/genética , Complexo de Golgi/metabolismo , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Southern Blotting , Clonagem Molecular , Escherichia coli/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Teste de Complementação Genética , Genótipo , Sistemas de Informação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Plasmídeos , Mapeamento por Restrição , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência do Ácido Nucleico
14.
J Cell Biol ; 114(4): 671-9, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1907974

RESUMO

In the yeast secretory pathway, two genes SEC12 and SAR1, which encode a 70-kD integral membrane protein and a 21-kD GTP-binding protein, respectively, cooperate in protein transport from the ER to the Golgi apparatus. In vivo, the elevation of the SAR1 dosage suppresses temperature sensitivity of the sec12 mutant. In this paper, we show cell-free reconstitution of the ER-to-Golgi transport that depends on both of these gene products. First, the membranes from the sec12 mutant cells reproduce temperature sensitivity in the in vitro ER-to-Golgi transport reaction. Furthermore, the addition of the Sar1 protein completely suppresses this temperature-sensitive defect of the sec12 membranes. The analysis of Sar1p partially purified by E. coli expression suggests that GTP hydrolysis is essential for Sar1p to execute its function.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Complexo de Golgi/metabolismo , Saccharomyces cerevisiae/metabolismo , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Trifosfato/metabolismo , Cinética , Peso Molecular , Biossíntese de Proteínas , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Temperatura , Transcrição Gênica
15.
J Cell Biol ; 107(3): 851-63, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3047151

RESUMO

SEC12, a gene that is required for secretory, membrane, and vacuolar proteins to be transported from the endoplasmic reticulum to the Golgi apparatus, has been cloned from a genomic library by complementation of a sec12 ts mutation. Genetic analysis has shown that the cloned gene integrates at the SEC12 locus and that a null mutation at the locus is lethal. The DNA sequence predicts a protein of 471 amino acids containing a hydrophobic stretch of 19 amino acids near the COOH terminus. To characterize the gene product (Sec12p) in detail, a lacZ-SEC12 gene fusion has been constructed and a polyclonal antibody raised against the hybrid protein. The antibody recognizes Sec12p as a approximately 70-kD protein that sediments in a mixed membrane fraction that includes endoplasmic reticulum. Sec12p is not removed from the membrane fraction by treatment at high pH and high salt and is not degraded by exogenous protease unless detergent is present. Glycosylation of Sec12p during biogenesis is indicated by an electrophoretic mobility shift of the protein that is influenced by tunicamycin and by imposition of an independent secretory pathway block. We suggest that Sec12p is an integral membrane glycoprotein with a prominent domain that faces the cytoplasm where it functions to promote protein transport to the Golgi apparatus. In the process of transport, Sec12p itself may migrate to the Golgi apparatus and function in subsequent transport events.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas Fúngicas/metabolismo , Complexo de Golgi/metabolismo , Glicoproteínas de Membrana/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Fúngico/genética , Genes Fúngicos , Teste de Complementação Genética , Glicosilação , Glicoproteínas de Membrana/genética , Microscopia Eletrônica , Dados de Sequência Molecular , Mutação , Hibridização de Ácido Nucleico , Plasmídeos , Processamento de Proteína Pós-Traducional , RNA Fúngico/análise , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Transcrição Gênica
16.
J Cell Biol ; 134(2): 279-93, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8707815

RESUMO

Yeast Sec12p is a type II transmembrane protein in the ER, which is essential for the formation of transport vesicles. From biochemical and morphological lines of evidence, we have proposed that Sec12p is localized to the ER by two mechanisms: static retention in the ER and dynamic retrieval from the early Golgi compartment. We have also shown that Rer1p, a membrane protein in the Golgi, is required for correct localization of Sec12p. In the present study, we have performed a systematic analysis to determine the ER localization signals in Sec12p corresponding to these two mechanisms. Both the transmembrane domain (TMD) and the NH2-terminal cytoplasmic domain of Sec12p show the ability to localize the protein to the ER. The effect of the TMD is potent and sufficient by itself for the ER localization and is strongly dependent on Rer1p. On the other hand, the cytoplasmic domain shows a moderate ER-localization capability which is independent of Rer1p. The rate of mannosyl modification has been measured to distinguish between retention and retrieval. The cytoplasmic domain significantly delays the transport from the ER to the cis-Golgi. In contrast, the TMD shows only a subtle retardation in the transport from the ER to the cis-Golgi but strictly prevents the transport beyond there. From these observations, we conclude that the TMD mainly acts as the retrieval signal and the cytoplasmic domain contains the retention signal. This study not only supports the two-mechanisms hypothesis but also provides powerful tools to dissect the two.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas Fúngicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , Citoplasma/metabolismo , DNA Fúngico , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Proteínas Fúngicas/genética , Fatores de Troca do Nucleotídeo Guanina , Manose , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Mutação , Sinais Direcionadores de Proteínas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular
17.
J Cell Biol ; 152(5): 935-44, 2001 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11238450

RESUMO

Rer1p, a yeast Golgi membrane protein, is required for the retrieval of a set of endoplasmic reticulum (ER) membrane proteins. We present the first evidence that Rer1p directly interacts with the transmembrane domain (TMD) of Sec12p which contains a retrieval signal. A green fluorescent protein (GFP) fusion of Rer1p rapidly cycles between the Golgi and the ER. Either a lesion of coatomer or deletion of the COOH-terminal tail of Rer1p causes its mislocalization to the vacuole. The COOH-terminal Rer1p tail interacts in vitro with a coatomer complex containing alpha and gamma subunits. These findings not only give the proof that Rer1p is a novel type of retrieval receptor recognizing the TMD in the Golgi but also indicate that coatomer actively regulates the function and localization of Rer1p.


Assuntos
Complexo I de Proteína do Envoltório/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Fúngicas/metabolismo , Complexo de Golgi/química , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Complexo I de Proteína do Envoltório/química , Complexo I de Proteína do Envoltório/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Complexo de Golgi/metabolismo , Fatores de Troca do Nucleotídeo Guanina , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Lisina/genética , Lisina/metabolismo , Glicoproteínas de Membrana/química , Proteínas de Membrana/química , Proteínas de Membrana/genética , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Subunidades Proteicas , Transporte Proteico , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Alinhamento de Sequência , Vacúolos/metabolismo , Proteínas de Transporte Vesicular
18.
Endoscopy ; 41(6): 498-503, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19533552

RESUMO

BACKGROUND: We retrospectively evaluated the predictive factors for lymph node metastasis in poorly differentiated early gastric cancer (poorly differentiated tubular adenocarcinoma, signet-ring cell carcinoma, mucinous adenocarcinoma) in order to examine the possibility of endoscopic resection for poorly differentiated early gastric cancer. METHODS: A total of 573 patients with histologically poorly differentiated type early gastric cancer (269 mucosal and 304 submucosal), who had undergone curative gastrectomy, were enrolled in this study. Risk factors for lymph node metastasis were evaluated by univariate and logistic regression analysis. RESULTS: Lymph node metastasis was observed in 74 patients (12.9%) (6 with mucosal cancer and 68 with submucosal cancer). By univariate analysis risk factors for lymph node metastasis were lymphovascular invasion (LVI) (presence), depth of invasion (submucosa), and tumor diameter (> 20 mm), ulcer or ulcer scar (presence), and histological type (mucinous adenocarcinoma). By multivariate analysis, risk factors for lymph node metastasis were LVI, depth of invasion, and tumor diameter. In mucosal cancers, the incidence of lymph node metastasis was 0% irrespective of LVI in tumors smaller than 20 mm, and 1.7% in tumors 20 mm or larger without LVI. In submucosal cancers, the incidence of lymph node metastasis was 2.4% in tumors smaller than 20 mm without LVI. CONCLUSIONS: A histologically poorly differentiated type mucosal gastric cancer measuring less than 20 mm and without LVI may be a candidate for endoscopic resection. This result should be confirmed in a larger study with many patients.


Assuntos
Adenocarcinoma Mucinoso/patologia , Adenocarcinoma/patologia , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma Mucinoso/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células em Anel de Sinete/cirurgia , Feminino , Previsões , Gastrectomia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/cirurgia
19.
Photodermatol Photoimmunol Photomed ; 25(1): 37-40, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19152514

RESUMO

BACKGROUND/PURPOSE: Topical 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) is effective for actinic keratosis (AK); few studies have examined Oriental patients. The aim of this study is to assess the efficacy of PDT for the treatment of Japanese AK patients classified by lesion size and histological severity. METHODS: Thirty patients with solitary AK lesions were divided into two groups according to diameter: a small lesion group (SL), diameter < or =10 mm and a larger lesion group (LL), diameter >10 mm, and histological severity: Group I (mild and moderate) and Group II (severe). After application of 20% ALA for 4 h, exposure to an excimer-dye laser at 630 nm was performed at a dose of 50 J/cm(2) three times at an interval of 7 days. Therapeutic effects were assessed and followed for 12 months. RESULTS: In all 10 SL patients, atypical cells disappeared after PDT and did not recur for 12 months. However, for the 20 LL patients, recurrence was seen in 2 of the 14 Group I patients, while 4 of 6 Group II patients showed residual tumor cells after the first PDT session. CONCLUSION: The present study demonstrated that ALA-PDT might be useful for treatment of Japanese AK. The therapeutic outcome might depend on the lesion size and the histopathological severity.


Assuntos
Ceratose Actínica/tratamento farmacológico , Ceratose Actínica/patologia , Fotoquimioterapia , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Feminino , Humanos , Ceratose Actínica/classificação , Masculino , Pessoa de Meia-Idade , Projetos Piloto
20.
Clin Exp Dermatol ; 34(3): 385-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19077103

RESUMO

BACKGROUND: Photodynamic therapy (PDT) with 5-aminolaevulinic acid (5-ALA) is a noninvasive and effective treatment for superficial skin cancers. Etretinate, a derivate of vitamin A, with the chemical formula ethyl(2E,4E,6E,8E)-9-(4-methoxy-2,3,6-trimethylphenyl)-3,7-dimethyl-2,4,6,8-nona-tetraenoate, has been reported to have antitumour effects and to regulate the proliferation and differentiation of skin cancers. OBJECTIVE: In order to develop more efficient PDT, we investigated whether etretinate enhanced the cytotoxic action of ALA-based PDT against human squamous cell carcinoma cell line, HSC-5. METHOD: The in vitro cytotoxicity was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptotic cells were detected by double-staining with fluorescent annexin V and propidium iodide. Intracellular protoporphyrin IX (PpIX) converted from exogenous ALA was measured by a fluorescence meter. RESULTS: HSC-5 cells pretreated with a nontoxic concentration of etretinate became more susceptible to the cytotoxic action of ALA-based PDT. Etretinate-pretreated cells underwent apoptosis in response to ALA-based PDT. Etretinate pretreatment resulted in enhanced accumulation of ALA-dependent intracellular PpIX. CONCLUSIONS: The results suggest that etretinate enhances the susceptibility of HSC-5 cells to ALA-based PDT via the intracellular increase of ALA-dependent PpIX. Etretinate might be useful for improvement of ALA-based PDT.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Etretinato/farmacologia , Ceratolíticos/farmacologia , Fotoquimioterapia/métodos , Neoplasias Cutâneas/tratamento farmacológico , Ácido Aminolevulínico/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Morte Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação de Medicamentos , Sinergismo Farmacológico , Humanos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
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