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1.
Genes Cells ; 25(1): 6-21, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31957229

RESUMO

Motility often plays a decisive role in the survival of species. Five systems of motility have been studied in depth: those propelled by bacterial flagella, eukaryotic actin polymerization and the eukaryotic motor proteins myosin, kinesin and dynein. However, many organisms exhibit surprisingly diverse motilities, and advances in genomics, molecular biology and imaging have showed that those motilities have inherently independent mechanisms. This makes defining the breadth of motility nontrivial, because novel motilities may be driven by unknown mechanisms. Here, we classify the known motilities based on the unique classes of movement-producing protein architectures. Based on this criterion, the current total of independent motility systems stands at 18 types. In this perspective, we discuss these modes of motility relative to the latest phylogenetic Tree of Life and propose a history of motility. During the ~4 billion years since the emergence of life, motility arose in Bacteria with flagella and pili, and in Archaea with archaella. Newer modes of motility became possible in Eukarya with changes to the cell envelope. Presence or absence of a peptidoglycan layer, the acquisition of robust membrane dynamics, the enlargement of cells and environmental opportunities likely provided the context for the (co)evolution of novel types of motility.


Assuntos
Movimento Celular/genética , Movimento Celular/fisiologia , Flagelos/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Animais , Bactérias , Evolução Biológica , Dineínas/metabolismo , Evolução Molecular , Flagelos/genética , Humanos , Cinesinas/metabolismo , Miosinas/metabolismo , Filogenia
2.
Heart Vessels ; 33(7): 793-801, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29285566

RESUMO

Biodegradable gelatin hydrogel sheet (BGHS) incorporating basic fibroblast growth factor (bFGF) may inhibit the progression of abdominal aortic aneurysm (AAA). We investigated whether AAA in a rat model treated with BGHS soaked with bFGF can suppress aortic expansion and recover the contractile response of aneurysmal aortic wall. Experimental AAA was induced in 10-week-old male Sprague-Dawley rats with intra-aortic elastase infusion. Aortas of these rats were assigned to 4 groups (n = 6 each) as follows: Control group, aortas infused with saline; Elastase only group, aortas infused with elastase; Hydrogel group, aortas wrapped with saline-soaked BGHS after elastase infusion; and bFGF group, aortas wrapped with bFGF (100 µg)-soaked BGHS after elastase infusion. Preoperatively and on postoperative day (POD)7 and POD14, mean aortic maximal diameter was measured ultrasonographically. Aortic expansion ratio was calculated as: (post-infusion aortic diameter on POD14/pre-infusion aortic diameter × 100). Aortas were stained with Elastica van Gieson and α-smooth muscle actin to measure the ratio of elastic fibers and α-smooth muscle actin-positive cells area to the media area. Aortas on POD14 were cut into 2-mm rings and treated with contractile agent, then tension was recorded using myography. Maximum aorta diameters were significantly greater in Elastase only group, Hydrogel group, and bFGF group than in Control group (on POD14). Maximum diameter was significantly lower in bFGF group (3.52 ± 0.4 mm) than in Elastase only group (6.21 ± 1.4 mm on POD14, P < .05). On histological analysis, ratio of the area staining positively for elastic fibers was significantly greater in bFGF group (7.43 ± 1.8%) than in Elastase only group (3.76 ± 2.9%, P < .05). The ratio for α-smooth muscle actin-positive cells was significantly lower in Elastase only group (38.3 ± 5.1%) than in Control group (49.8 ± 6.7%, P < .05). No significant differences were seen between Elastase only group and bFGF group, but ratios tended to be increased in bFGF group. Consecutive mean contractile tensions were significantly higher in bFGF group than in Elastase only group. Maximum contractile tension was significantly higher in bFGF group (1.3 ± 0.4 mN) than in Elastase only group (0.4 ± 0.2 mN, P < .05). Aortic expansion can be suppressed and contractile responses of aneurysmal aortic wall recovered using BGHS incorporating bFGF.


Assuntos
Implantes Absorvíveis , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Recuperação de Função Fisiológica , Vasoconstrição/fisiologia , Animais , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/fisiopatologia , Modelos Animais de Doenças , Gelatina , Hidrogel de Polietilenoglicol-Dimetacrilato , Masculino , Ratos Sprague-Dawley , Ultrassonografia
3.
Int J Syst Evol Microbiol ; 66(12): 5417-5423, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27692037

RESUMO

A cellulolytic and agarolytic bacterial strain, designated 12-2T, was isolated from a piece of cotton rope fragment washed ashore on a beach and was studied phenotypically, genotypically and phylogenetically. Analyses of 16S rRNA and gyrB gene sequences and DNA base composition suggested that the strain is a member of the genus Gilvimarinus. However, levels of 16S rRNA and gyrB gene sequence similarity between it and the type strains of Gilvimarinus species were no higher than 97.9 and 78.7 %, respectively, suggesting that the strain is distinct. Moreover, the results of DNA-DNA hybridization experiments and physiological characterization clearly differentiated the strain from its closest neighbours. The strain is therefore considered to represent a novel species of the genus Gilvimarinus, for which the name Gilvimarinus japonicus sp. nov. is proposed. The type strain is 12-2T (=NBRC 111987T=KCTC 52141T).


Assuntos
Gammaproteobacteria/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Girase/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Japão , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
4.
J Card Surg ; 31(6): 380-2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27102973

RESUMO

Anomalous left coronary artery from the pulmonary artery (ALCAPA) in adults is a rare congenital coronary abnormality. We report a case of ALCAPA in a 73-year-old female managed by total arterial revascularization. doi: 10.1111/jocs.12755 (J Card Surg 2016;31:380-382).


Assuntos
Síndrome de Bland-White-Garland/cirurgia , Ponte de Artéria Coronária/métodos , Idoso , Doenças Assintomáticas , Síndrome de Bland-White-Garland/diagnóstico , Feminino , Humanos
5.
Surg Today ; 44(3): 550-2, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23624612

RESUMO

A 73-year-old man with a severely stenosed bicuspid valve and an aneurysm of the ascending aorta underwent valve and aortic surgery. Preoperative imaging revealed a single coronary artery arising from the right side of the sinus of Valsalva and a branch that perfused into the left side of the heart to pass through the front of the pulmonary artery. We replaced the aortic valve and ascending aorta, painstakingly avoiding damage to the coronary artery and obstruction of the sole coronary ostium.


Assuntos
Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/anormalidades , Implante de Prótese Vascular , Anomalias dos Vasos Coronários , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Idoso , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Doença da Válvula Aórtica Bicúspide , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico , Ecocardiografia Transesofagiana , Doenças das Valvas Cardíacas/diagnóstico , Humanos , Masculino , Seio Aórtico , Tomografia Computadorizada por Raios X
6.
Surg Today ; 44(1): 185-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23052755

RESUMO

This report describes a case of synchronous left atrial myxomas from Carney complex resected through a right thoracotomy. The patient was a 30-year-old female that had previously been diagnosed with Carney complex following a genetic examination. Preoperative echocardiography showed a left atrial tumor, but intraoperative inspection revealed another tumor in the left atrium. Carney complex was first described in the 1980s and cardiac myxoma from Carney complex can occur in any cardiac chamber, presenting multiple times with postoperative recurrences, occurring at any age and without any predilection for gender, and is inherited in an autosomal-dominant manner. Treatment for cardiac myxoma from Carney complex is very important for patient mortality and morbidity and, despite the endocrine nature of the disorder, cardiologists and cardiac surgeons play an important role.


Assuntos
Complexo de Carney/cirurgia , Neoplasias Cardíacas/cirurgia , Mixoma/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Toracotomia/métodos , Adulto , Complexo de Carney/diagnóstico por imagem , Complexo de Carney/patologia , Ecocardiografia , Feminino , Átrios do Coração , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Humanos , Mixoma/diagnóstico por imagem , Mixoma/patologia , Resultado do Tratamento
7.
Surg Today ; 44(10): 1946-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23744242

RESUMO

A 55-year-old male with an intermittent high-grade fever was diagnosed with infective endocarditis. He was indicated for surgery because periodic echocardiography revealed worsening mitral regurgitation and growing vegetation despite medication. An aneurysm of the P2 portion and all vegetations were removed via quadrangular resection of the P2 leaflet, and then the defect was repaired. An intraoperative assessment identified Staphylococcus lugdunensis as the causative bacterium. After postoperative antibiotic therapy for 5 weeks, the patient was discharged without either mitral regurgitation or signs of infection. Infective endocarditis caused by aggressive and destructive S. lugdunensis should be promptly and accurately treated via a surgical approach that prevents progressive tissue destruction and simplifies the surgical procedure for repair, rather than replacement.


Assuntos
Endocardite/microbiologia , Endocardite/cirurgia , Anuloplastia da Valva Mitral/métodos , Insuficiência da Valva Mitral/cirurgia , Infecções Estafilocócicas , Staphylococcus lugdunensis , Endocardite/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/etiologia , Resultado do Tratamento
8.
J Cardiothorac Surg ; 19(1): 13, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245766

RESUMO

BACKGROUND: Left atrial myxoma is the most common benign tumor, with the growth rate remaining unknown because specific symptoms do not present until the tumor grows to a certain size. Early surgical management is performed in most cases once it is detected by physicians. Despite cardiac myxomas commonly being perceived as slow-growing tumors, rapid enlargement of myxomas has been reported. CASE PRESENTATION: A 64-year-old woman was referred to our hospital with a diagnosis of a left atrial tumor. The pointed tumor changed morphologically in a few hours, and her respiratory condition, which had been normal at admission, suddenly deteriorated. Emergent surgery was performed, and the diagnosis was myxoma with multiple intratumor massive hematomas. The patient recovered uneventfully and was discharged on postoperative day 12 without any complications. CONCLUSIONS: We report an extremely rare case of left atrial myxoma rapidly expanded due to acute multiple hemorrhages within itself. Massive internal hemorrhage alters the size, shape, and fragility of the tumor. We should recognize the potential risk of internal hemorrhage that may lead to acute deterioration of the so-called "slow-growing benign" tumors, such as myxomas.


Assuntos
Neoplasias Cardíacas , Mixoma , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/diagnóstico por imagem , Hemorragia , Mixoma/complicações , Mixoma/diagnóstico , Mixoma/cirurgia , Átrios do Coração/cirurgia , Átrios do Coração/patologia , Hematoma/complicações
9.
Radiology ; 267(3): 948-55, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23392427

RESUMO

PURPOSE: To compare vascular measurements to determine stent types and configurations for abdominal endovascular aneurysm repair (EVAR) by comparing results of contrast material-enhanced computed tomographic (CT) angiography and nonenhanced magnetic resonance (MR) angiography. MATERIALS AND METHODS: This prospective study was institutional review board approved, and all patients provided written informed consent. Fifty patients (45 men and five women; mean age, 76.0 years) admitted for elective abdominal EVAR underwent preoperative abdominal CT angiography (triplanar reformatted images; section thickness of 1-3 mm) and nonenhanced MR angiography (triplanar two-dimensional single-shot turbo field-echo images; section thickness of 6 mm). Two observers independently completed standard measurement and device selection forms for endovascular stent planning for CT and MR angiography. Pearson and intraclass correlation coefficients were calculated to evaluate intermodality and interobserver differences. RESULTS: No significant difference was found in aortic neck diameter (observer 1: CT, 18.5 mm; MR, 19.0 mm; P = .43) (observer 2: CT, 19.6 mm; MR, 19.3 mm; P = .59), aortic neck diameter 15 mm distal to the lowest renal artery (observer 1: CT, 19.2 mm; MR, 19.2 mm; P = .38) (observer 2: CT, 19.6 mm; MR, 19.6 mm; P = .91), aortic neck length (observer 1: CT, 43.6 mm; MR, 43.6 mm; P = .85) (observer 2: CT, 44.4 mm; MR, 44.0 mm; P = .93), or other key vascular measurements (P = .23-.99) for preoperative planning. These included aneurysm diameter, lowest renal artery to aortic bifurcation length, aortic bifurcation diameter, common iliac artery diameters, external iliac artery diameters, length between orifices of lower renal and internal iliac arteries, and iliac artery sealing length. CT and MR angiography measurements showed very strong correlation (r = 0.92-0.99). Intraclass correlation coefficients between observers ranged from 0.90 to 0.98. Stent types and configurations determined with CT measurements remained unaltered when reassessed with MR measurements. CONCLUSION: Measurements obtained with nonenhanced MR angiography appear equally accurate to those of CT angiography in the preoperative planning of abdominal EVAR.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares , Angiografia por Ressonância Magnética/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia/métodos , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Meios de Contraste , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Prospectivos
10.
Nat Chem Biol ; 8(1): 86-92, 2011 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-22101603

RESUMO

The conformational fluctuation of enzymes has a crucial role in reaction acceleration. However, the contribution to catalysis enhancement of individual substates with conformations far from the average conformation remains unclear. We studied the catalytic power of the rotary molecular motor F(1)-ATPase from thermophilic Bacillus PS3 as it was stalled in transient conformations far from a stable pausing angle. The rate constants of ATP binding and hydrolysis were determined as functions of the rotary angle. Both rates exponentially increase with rotation, revealing the molecular basis of positive cooperativity among three catalytic sites: elementary reaction steps are accelerated via the mechanical rotation driven by other reactions on neighboring catalytic sites. The rate enhancement induced by ATP binding upon rotation was greater than that brought about by hydrolysis, suggesting that the ATP binding step contributes more to torque generation than does the hydrolysis step. Additionally, 9% of the ATP-driven rotary step was supported by thermal diffusion, suggesting that acceleration of the ATP docking process occurs via thermally agitated conformational fluctuations.


Assuntos
Bacillus/enzimologia , Biocatálise , ATPases Translocadoras de Prótons/química , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Hidrólise , Cinética , Modelos Moleculares , Ligação Proteica , ATPases Translocadoras de Prótons/metabolismo , Especificidade por Substrato
11.
J Vasc Surg ; 56(1): 219-22, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22480763

RESUMO

This case report describes a right subclavian artery aneurysm secondary to long-term repetitive blunt trauma. A 62-year-old man with a right subclavian artery aneurysm had had a history of bird hunting using a shotgun that impacted substantially against his right clavicula and shoulder weekly for >20 years. The patient underwent open repair with partial sternotomy and distal balloon control. The aneurysmal sac was resected, and the right subclavian artery was reconstructed with a primary end-to-end anastomosis. Histopathologic examination of the resected aneurysmal wall revealed that all three layers of the arterial wall were comparatively intact, with fibrosis and lipid deposition in the intima and in various degrees of degeneration in the media, suggesting a true aneurysm.


Assuntos
Aneurisma/cirurgia , Traumatismos em Atletas/cirurgia , Transtornos Traumáticos Cumulativos/cirurgia , Artéria Subclávia , Ferimentos não Penetrantes/cirurgia , Anastomose Cirúrgica , Aneurisma/diagnóstico por imagem , Traumatismos em Atletas/diagnóstico por imagem , Transtornos Traumáticos Cumulativos/diagnóstico por imagem , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ferimentos não Penetrantes/diagnóstico por imagem
12.
Transfus Apher Sci ; 47(3): 263-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22980916

RESUMO

We report the death of a 61-year-old Japanese man massively transfused during and after emergency aortic surgery. Postoperative on day 8, he died after cardiac arrest associated with hyperkalemia. Indirect antiglobulin testing demonstrated both anti-Di(b) and anti-E antibodies pre-transfusion, and elevation of their titers as the delayed hemolytic transfusion reaction evolved. Monocyte monolayer assay (induction of reactive monocytes) and flow cytometry (increase of IgG1 and/or IgG3) gave evidence of the clinical significance of both antibodies. Anti-Di(b) must be considered when an antibody to a high incidence antigen is found in Japanese and other Mongoloid populations.


Assuntos
Incompatibilidade de Grupos Sanguíneos/sangue , Transfusão de Eritrócitos/métodos , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Dissecção Aórtica/cirurgia , Anticorpos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Procedimentos Cirúrgicos Cardíacos/métodos , Transfusão de Eritrócitos/efeitos adversos , Humanos , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Fenótipo
14.
Proc Natl Acad Sci U S A ; 105(14): 5390-5, 2008 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-18385381

RESUMO

Although several models have been proposed to account for how cytoskeleton polymerization drives protrusion in cell motility, the precise mechanism remains controversial. Here, we show that, in addition to force exerted directly against the membrane by growing filaments, the way elongating filaments pack also contributes to protrusion by generating an expansion of the cytoskeleton gel. Tomography shows that filament packing in the major sperm protein (MSP) -based nematode sperm-motility machinery resembles that observed with rigid rods. Maximum rod-packing density decreases dramatically as the rods lengthen. Therefore, as filaments elongate, the cytoskeleton gel expands to accommodate their packing less densely. This volume expansion combines with polymerization to drive protrusion. Consistent with this hypothesis, an engineered MSP mutant that generates shorter filaments shows higher filament-packing density and slower movement.


Assuntos
Ascaris suum/fisiologia , Citoesqueleto/metabolismo , Proteínas de Helminto/metabolismo , Citoesqueleto de Actina/metabolismo , Animais , Proteínas de Helminto/genética , Proteínas Motores Moleculares , Movimento , Proteínas Mutantes , Tomografia
15.
SAGE Open Med Case Rep ; 9: 2050313X211037784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394939

RESUMO

We reported a rare case of spontaneous frank rupture of a small (4 mm) penetrating aortic ulcer in the ascending aorta resulted in catastrophic bleeding. The ulcer only created a pinhole wound in the adventitia without saccular aneurysms, intramural hematomas, or aortic dissections. Notably, the wound could be directly closed because the aortic wall was intact only 5 mm away from the bleeding site. The postoperative course was uneventful, and the patient was discharged on the 11th postoperative day. After 8 months, follow-up computed tomography showed no abnormality of the aortic wall at the repair site.

16.
Korean J Radiol ; 22(4): 513-524, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33543842

RESUMO

OBJECTIVE: To assess the noncontrast two-dimensional single-shot balanced turbo-field-echo magnetic resonance angiography (b-TFE MRA) features of the abdominal aortic aneurysm (AAA) status following endovascular aneurysm repair (EVAR) and evaluate to detect endoleaks (ELs). MATERIALS AND METHODS: We examined four aortic stent-grafts in a phantom study to assess the degree of metallic artifacts. We enrolled 46 EVAR-treated patients with AAA and/or common iliac artery aneurysm who underwent both computed tomography angiography (CTA) and b-TFE MRA after EVAR. Vascular measurements on CTA and b-TFE MRA were compared, and signal intensity ratios (SIRs) of the aneurysmal sac were correlated with the size changes in the AAA after EVAR (AAA prognoses). Furthermore, we examined six feasible b-TFE MRA features for the assessment of ELs. RESULTS: There were robust intermodality (r = 0.92-0.99) correlations and interobserver (intraclass correlation coefficient = 0.97-0.99) agreement. No significant differences were noted between SIRs and aneurysm prognoses. Moreover, "mottled high-intensity" and "creeping high-intensity with the low-band rim" were recognized as significant imaging findings suspicious for the presence of ELs (p < 0.001), whereas "no signal black spot" and "layered high-intensity area" were determined as significant for the absence of ELs (p < 0.03). Based on the two positive features, sensitivity, specificity, and accuracy for the detection of ELs were 77.3%, 91.7%, and 84.8%, respectively. Furthermore, the k values (0.40-0.88) displayed moderate-to-almost perfect agreement. CONCLUSION: Noncontrast MRA could be a promising imaging modality for ascertaining patient follow-up after EVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Endoleak/diagnóstico por imagem , Angiografia por Ressonância Magnética , Idoso , Idoso de 80 Anos ou mais , Implante de Prótese Vascular , Meios de Contraste/química , Endoleak/diagnóstico , Endoleak/etiologia , Procedimentos Endovasculares , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Tomografia Computadorizada por Raios X
17.
Gen Thorac Cardiovasc Surg ; 68(4): 392-395, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30968260

RESUMO

Hemorrhagic pericardial effusion is life-threatening and mostly occurs during pericarditis; however, its underlying mechanism is unclear. We report a case of pericardial hematoma with obvious hemorrhage. A 56-year-old man without prior chest trauma presenting with exertional dyspnea and abdominal fullness was treated for idiopathic pericarditis. The echocardiogram showed a thickened pericardium with effusion. Imaging showed extravasation and neovascularization. Following ineffective pharmacotherapy, we performed pericardiectomy. The site of bleeding was undetectable. Because parietal pericardiectomy with hematoma evacuation did not improve diastolic function, we removed the epicardium. During the follow-up period, the patient remained almost asymptomatic. We identified neovascularization as the potential source of idiopathic pericardial hemorrhage.


Assuntos
Hemorragia/etiologia , Derrame Pericárdico/etiologia , Pericardite Constritiva/complicações , Pericárdio/patologia , Diástole , Dispneia , Ecocardiografia , Hemorragia/diagnóstico por imagem , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico por imagem , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/cirurgia , Pericardiectomia , Pericardite Constritiva/diagnóstico por imagem , Pericardite Constritiva/cirurgia , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia
18.
Biophys J ; 96(3): 1210-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19186155

RESUMO

Tributyltin chloride (TBT-Cl) is an endocrine disruptor found in many animal species, and it is also known to be an inhibitor for the V-ATPases that are emerging as potential targets in the treatment of diseases such as osteoporosis and cancer. We demonstrated by using biochemical and single-molecular imaging techniques that TBT-Cl arrests an elementary step for rotary catalysis of the V(1) motor domain. In the presence of TBT-Cl, the consecutive rotation of V(1) paused for a long duration ( approximately 0.5 s), even at saturated ATP concentrations, and the pausing positions were localized at 120 degrees intervals. Analysis of both the pausing time and moving time revealed that TBT-Cl has little effect on the binding affinity for ATP, but, rather, it arrests the catalytic event(s). This is the first report to demonstrate that an inhibitor arrests an elementary step for rotary catalysis of a V-type ATP-driven rotary motor.


Assuntos
Disruptores Endócrinos/toxicidade , Thermus thermophilus/enzimologia , Compostos de Trialquitina/toxicidade , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Biocatálise/efeitos dos fármacos , Cinética , Movimento , Estrutura Terciária de Proteína , Rotação , ATPases Vacuolares Próton-Translocadoras/química , ATPases Vacuolares Próton-Translocadoras/metabolismo
19.
J Cardiothorac Vasc Anesth ; 22(2): 204-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18375321

RESUMO

OBJECTIVE: To assess the effect of human atrial natriuretic peptide (HANP) on the pulmonary and systemic circulations during infrarenal abdominal aortic aneurysmectomy. DESIGN: A prospective, randomized study. SETTING: A university hospital. PARTICIPANTS: Forty-five patients undergoing infrarenal abdominal aortic aneurysmectomy. INTERVENTIONS: Abdominal aortic aneurysmectomy patients were randomly assigned to 1 of 3 groups (n = 15 for each group). They were infused with normal saline solution (SA), 0.02 microg/kg/min of HANP (LH), or 0.05 microg/kg/min of HANP (HH), starting 5 minutes after clamping. Hemodynamic variables were measured before/after clamping and unclamping. MEASUREMENTS AND MAIN RESULTS: Both mean pulmonary arterial pressure (MPAP) and the pulmonary vascular resistance index (PVRI) increased (v baseline) in the SA group. HANP attenuated the rises in MPAP and PVRI dose dependently (LH and HH groups v SA). Mean arterial pressure and systemic vascular resistance index were not significantly different among the 3 groups. CONCLUSION: HANP, infused during aortic clamping and abdominal aortic aneurysmectomy, attenuates the rises in pulmonary artery pressure and vascular resistance without severe systemic hypotension. This may result from direct and/or indirect pulmonary vascular effects of HANP because no HANP-induced changes in endothelin-1, angiotensin-II, and thromboxane B(2) were detected.


Assuntos
Aorta Abdominal/fisiologia , Aneurisma da Aorta Abdominal/tratamento farmacológico , Fator Natriurético Atrial/uso terapêutico , Artéria Pulmonar/fisiologia , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Pressão Sanguínea/fisiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/prevenção & controle , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/uso terapêutico , Estudos Prospectivos , Resistência Vascular/fisiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos
20.
Phys Rev E ; 97(5-1): 052401, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29906928

RESUMO

Living cells sense the mechanical properties of their surrounding environment and respond accordingly. Crawling cells detect the rigidity of their substratum and migrate in certain directions. They can be classified into two categories: slow-moving and fast-moving cell types. Slow-moving cell types, such as fibroblasts, smooth muscle cells, mesenchymal stem cells, etc., move toward rigid areas on the substratum in response to a rigidity gradient. However, there is not much information on rigidity sensing in fast-moving cell types whose size is ∼10 µm and migration velocity is ∼10 µm/min. In this study, we used both isotropic substrata with different rigidities and an anisotropic substratum that is rigid on the x axis but soft on the y axis to demonstrate rigidity sensing by fast-moving Dictyostelium cells and neutrophil-like differentiated HL-60 cells. Dictyostelium cells exerted larger traction forces on a more rigid isotropic substratum. Dictyostelium cells and HL-60 cells migrated in the "soft" direction on the anisotropic substratum, although myosin II-null Dictyostelium cells migrated in random directions, indicating that rigidity sensing of fast-moving cell types differs from that of slow types and is induced by a myosin II-related process.


Assuntos
Movimento Celular , Dictyostelium/citologia , Fenômenos Mecânicos , Actomiosina/metabolismo , Anisotropia , Fenômenos Biomecânicos , Diferenciação Celular , Dictyostelium/metabolismo , Elasticidade , Células HL-60 , Humanos , Miosina Tipo II/metabolismo , Fatores de Tempo
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