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1.
Nature ; 626(8001): 990-998, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38383782

RESUMO

Electrode-based electrical stimulation underpins several clinical bioelectronic devices, including deep-brain stimulators1,2 and cardiac pacemakers3. However, leadless multisite stimulation is constrained by the technical difficulties and spatial-access limitations of electrode arrays. Optogenetics offers optically controlled random access with high spatiotemporal capabilities, but clinical translation poses challenges4-6. Here we show tunable spatiotemporal photostimulation of cardiac systems using a non-genetic platform based on semiconductor-enabled biomodulation interfaces. Through spatiotemporal profiling of photoelectrochemical currents, we assess the magnitude, precision, accuracy and resolution of photostimulation in four leadless silicon-based monolithic photoelectrochemical devices. We demonstrate the optoelectronic capabilities of the devices through optical overdrive pacing of cultured cardiomyocytes (CMs) targeting several regions and spatial extents, isolated rat hearts in a Langendorff apparatus, in vivo rat hearts in an ischaemia model and an in vivo mouse heart model with transthoracic optical pacing. We also perform the first, to our knowledge, optical override pacing and multisite pacing of a pig heart in vivo. Our systems are readily adaptable for minimally invasive clinical procedures using our custom endoscopic delivery device, with which we demonstrate closed-thoracic operations and endoscopic optical stimulation. Our results indicate the clinical potential of the leadless, lightweight and multisite photostimulation platform as a pacemaker in cardiac resynchronization therapy (CRT), in which lead-placement complications are common.


Assuntos
Terapia de Ressincronização Cardíaca , Desenho de Equipamento , Marca-Passo Artificial , Silício , Animais , Camundongos , Ratos , Terapia de Ressincronização Cardíaca/métodos , Endoscopia , Coração , Procedimentos Cirúrgicos Minimamente Invasivos , Isquemia Miocárdica/cirurgia , Isquemia Miocárdica/terapia , Miócitos Cardíacos , Semicondutores , Suínos , Modelos Animais
2.
Int Heart J ; 61(5): 979-983, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32921662

RESUMO

The Fontan procedure is a palliative surgery performed for patients with complex congenital heart disease who exhibit functional single ventricular physiology. Although clinical outcomes of the Fontan procedure have improved in recent years and most patients who undergo the procedure reach adulthood, Fontan-associated liver disease (FALD) is a noncardiovascular complication that has become increasingly common; its risk factors remain unknown.A total of 95 patients who underwent the Fontan procedure and who were followed up for at least three years at Gunma Children's Medical Center and Kitasato University Hospital between 1996 and 2015 were retrospectively enrolled in this study.The mean age of the patients at the time of Fontan procedure was 2.3 ± 1.4 years. Overall, 21 patients (23.1%) experienced FALD. All Fontan procedures were performed with extracardiac total cavopulmonary connection using 16-mm expanded polytetrafluoroethylene grafts. The presence of systemic right ventricle, requirement of pulmonary vasodilator, application of a non-fenestrated Fontan procedure, and absence of fenestration flow at the time of follow-up catheter examination were identified as predictors of FALD using univariate analysis. All these factors, except the requirement of pulmonary vasodilator, remained significant predictors of FALD in multivariate logistic regression analysis.Patients with a systemic right ventricle who undergo the Fontan procedure are at a high risk of FALD in the mid-term. Creating fenestration at the time of Fontan and maintaining the fenestration flow may reduce the mid-term risk of FALD.


Assuntos
Técnica de Fontan/métodos , Cardiopatias Congênitas/cirurgia , Hepatopatias/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Vasodilatadores/uso terapêutico , Adolescente , Alanina Transaminase/sangue , Anastomose Cirúrgica/métodos , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Pressão Venosa Central/fisiologia , Criança , Pré-Escolar , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Lactente , Hepatopatias/sangue , Modelos Logísticos , Masculino , Análise Multivariada , Complicações Pós-Operatórias/sangue , Estudos Retrospectivos , Fatores de Risco , Resistência Vascular
3.
Int J Mol Sci ; 19(12)2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30562962

RESUMO

Accumulating evidence suggests that histamine synthesis induced in several types of tumor tissues modulates tumor immunity. We found that a transient histamine synthesis was induced in CD11b⁺Gr-1⁺ splenocytes derived from BALB/c mice transplanted with a syngeneic colon carcinoma, CT-26, when they were co-cultured with CT-26 cells. Significant levels of IFN-γ were produced under this co-culture condition. We explored the modulatory roles of histamine on IFN-γ production and found that several histamine receptor antagonists, such as pyrilamine, diphenhydramine, JNJ7777120, and thioperamide, could significantly suppress IFN-γ production. However, suppression of IFN-γ production by these antagonists was also found when splenocytes were derived from the Hdc-/- BALB/c mice. Suppressive effects of these antagonists were found on IFN-γ production induced by concanavalin A or the combination of an anti-CD3 antibody and an anti-CD28 antibody in a histamine-independent manner. Murine splenocytes were found to express H1 and H2 receptors, but not H3 and H4 receptors. IFN-γ production in the Hh1r-/- splenocytes induced by the combination of an anti-CD3 antibody and an anti-CD28 antibody was significantly suppressed by these antagonists. These findings suggest that pyrilamine, diphenhydramine, JNJ7777120, and thioperamide can suppress IFN-γ production in activated splenocytes in a histamine-independent manner.


Assuntos
Antagonistas dos Receptores Histamínicos/farmacologia , Interferon gama/biossíntese , Baço/metabolismo , Animais , Linhagem Celular Tumoral , Histamina/genética , Histamina/metabolismo , Interferon gama/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Receptores Histamínicos H2/genética , Receptores Histamínicos H2/metabolismo , Baço/patologia
4.
J Artif Organs ; 20(2): 110-116, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28054177

RESUMO

Regional cerebral oximetry using near-infrared spectroscopy device, an INVOS 5100 C (Medtronic, Minneapolis, MN, USA), during cardiac surgery aims to avoid perioperative neurological impairment, especially during cardiopulmonary bypass. However, it is not uncommon to encounter critically low initial cerebral regional oxygen saturation or a low value unresponsive to intervention. Therefore, it is important to identify factors associated with low saturation value other than true cerebral hypoxia. We investigated the relationship between preoperative regional cerebral oxygen saturation and clinical variables during cardiac surgery. From January 2013 to May 2016, 462 patients underwent elective cardiac surgery. Patient's ≤12 years of age, with acute cerebral infarction, with previous intracranial hemorrhage or neurosurgery, with concomitant aortic surgery, and having off-pump coronary artery bypass surgery were excluded. The remaining 223 patients were monitored by intraoperative regional cerebral oximetry. Univariate analysis found that scalp-cortex distance, cerebrospinal fluid thickness, left ventricular ejection fraction, hemoglobin concentration, estimated glomerular filtration rate, and hemodialysis were significantly correlated with the initial regional oxygen saturation value. Multiple regression analysis revealed that scalp-cortex distance, left ventricular ejection fraction, hemoglobin, and hemodialysis remained as significant variables. A receiver operating characteristic analysis found that for a low initial regional oxygen saturation value of 40%, the thresholds of scalp-cortex distance, left ventricular ejection fraction, and hemoglobin concentration were 17.6 mm, 45.2%, and 7.5 g/dl, respectively. In conclusion, brain atrophy, poor left ventricular function, anemia, and hemodialysis were associated with low initial cerebral regional oxygen saturation values in adult cardiac surgery patients.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Circulação Cerebrovascular/fisiologia , Hipóxia Encefálica/diagnóstico , Adulto , Idoso , Feminino , Hemoglobinas/metabolismo , Humanos , Hipóxia Encefálica/etiologia , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Análise Multivariada , Oximetria , Estudos Retrospectivos , Sensibilidade e Especificidade , Espectroscopia de Luz Próxima ao Infravermelho
5.
J Basic Microbiol ; 55(7): 838-45, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25707451

RESUMO

Colwellia psychrerythraea strain 34H is an obligately psychrophilic bacterium that has been used as a model cold-adapted microorganism because of its psychrophilic growth profile, significant production of cold-active enzymes, and cryoprotectant extracellular polysaccharide substances. However, its fatty acid components, particularly trans unsaturated fatty acids and long-chain polyunsaturated fatty acids (LC-PUFAs), have not been fully investigated. In this study, we biochemically identified Δ9-trans hexadecenoic acid [16:1(9t)] and LC-PUFAs such as docosahexaenoic acid. These results are comparable with the fact that the strain 34H genome sequence includes pfa and cti genes that are responsible for the biosynthesis of LC-PUFAs and trans unsaturated fatty acids, respectively. Strain 34H cells grown under static conditions at 5 °C had higher levels of 16:1(9t) than those grown under shaken conditions, and this change was accompanied by an antiparallel decrease in the levels of Δ9-cis hexadecenoic acid [16:1(9c)], suggesting that the cis-to-trans isomerization reaction of 16:1(9c) is activated under static (microanaerobic) culture conditions, that is, the enzyme could be activated by the decreased dissolved oxygen concentration of cultures. On the other hand, the levels of LC-PUFAs were too low (less than 3% of the total), even for cells grown at 5 °C, to evaluate their cold-adaptive function in this bacterium.


Assuntos
Alteromonadaceae/química , Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Insaturados/análise , Ácidos Graxos trans/análise , Alteromonadaceae/enzimologia , Alteromonadaceae/genética , Alteromonadaceae/crescimento & desenvolvimento , Sequência de Bases , Temperatura Baixa , Isomerismo , Polissacarídeos
6.
J Artif Organs ; 17(1): 95-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24288020

RESUMO

Right heart failure is a critical complication in patients requiring mechanical ventricular support. However, it is often difficult to provide adequate right ventricular support in the acute phase. A 41-year-old woman diagnosed with dilated cardiomyopathy with severe right heart failure underwent implantation of a paracorporeal pulsatile left ventricular assist device (LVAD, Nipro Corporation, Tokyo, Japan) and a MERA monopivot centrifugal pump (Senko Medical Instrument Manufacturing Co., Ltd., Tokyo, Japan) as a right ventricular assist device (RVAD). The patient developed ischemic enteritis 3 weeks after surgery, necessitating fasting and reversal of anticoagulation therapy. A target international normalized ratio of 1.5 was selected, and aspirin administration was discontinued. Following recovery without thromboembolic events, the patient failed the RVAD discontinuation test. Five weeks after surgery, the monopivot centrifugal pump was exchanged for a pulsatile pump. No thrombus was evident on the centrifugal pump. The patient was undergoing cardiac rehabilitation at the time of this writing and awaiting heart transplantation.


Assuntos
Cardiomiopatia Dilatada/cirurgia , Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Implantação de Prótese/instrumentação , Adulto , Cardiomiopatia Dilatada/complicações , Feminino , Humanos
7.
Int Heart J ; 55(4): 377-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24881585

RESUMO

Previous studies have reported that the extracardiac Fontan procedure has excellent outcomes and a lower incidence of postoperative complications than the lateral tunnel procedure. However, thromboembolic events that occur after the Fontan procedure are a well-known cause of morbidity. We experienced a case of thrombosis of intra-atrial extracardiac conduit and the left pulmonary artery 2 years after a modified Fontan operation due to infective endocarditis (IE) despite prophylactic antiplatelet therapy. The patient underwent reoperation. The conduit in the right atrium (RA) was excised, and the thrombus in the vessels was removed. Because the fibrous tissue in the RA around the conduit was firm, the tissue was used as the "tunnel" for the Fontan route between the IVC and the ePTFE graft outside the RA instead of replacement using another alien graft. He was discharged on postoperative day 45 and was medicated with coumadin and aspirin. He is now being followed in our outpatient clinic and is still without any sign of infection.


Assuntos
Endocardite Bacteriana/microbiologia , Técnica de Fontan/efeitos adversos , Oclusão de Enxerto Vascular/microbiologia , Cardiopatias Congênitas/cirurgia , Artéria Pulmonar/patologia , Infecções Estafilocócicas/microbiologia , Trombose/microbiologia , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Bacteriemia/terapia , Pré-Escolar , Diagnóstico Diferencial , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/terapia , Seguimentos , Técnica de Fontan/métodos , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/terapia , Átrios do Coração/cirurgia , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Complicações Pós-Operatórias , Reoperação , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/terapia , Trombectomia/métodos , Trombose/diagnóstico , Trombose/terapia
8.
Int Heart J ; 55(1): 87-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24463916

RESUMO

According to several previous reports on persistent fifth aortic arch (PFAA), the presentation of the patients was usually either very mild when diagnosed by physical examination including upper body systemic hypertension and systolic murmur, or severe with ductal shock in the neonatal period. In our case, the clinical course was unique with relatively mild narrowing at the distal PFAA and an interrupted fourth aortic arch. It can be classified as medium severity based on the timing of presentation to the hospital. In the present case, severe LV dysfunction suggested sustained narrowing at the junction between the PFAA and the descending aorta and insufficient development of collateral arteries.We experienced a case with PFAA with severe LV dysfunction. These findings suggest another differential diagnosis for severe LV dysfunction in infancy.


Assuntos
Aorta Torácica/anormalidades , Disfunção Ventricular Esquerda/etiologia , Feminino , Humanos , Lactente , Índice de Gravidade de Doença
9.
Int Heart J ; 55(6): 550-1, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25297503

RESUMO

Fenestration-related massive aortic regurgitation is rare. The underlying mechanism is reported to be rupture of the fenestrated fibrous strand, and most ruptured cords have been reported in the bicuspid valve or in the right coronary cusp of the tricuspid aortic valve. We encountered a rare case of acute aortic regurgitation due to fibrous strand rupture in the fenestrated left coronary cusp. Preoperative echocardiography detected left coronary cusp prolapse, and operative findings revealed rupture of a fibrous strand in the left coronary cusp. For cases such as this, preoperative echocardiography would be useful for appropriate diagnosis.


Assuntos
Insuficiência da Valva Aórtica/etiologia , Valva Aórtica/patologia , Idoso , Insuficiência da Valva Aórtica/patologia , Humanos , Masculino
10.
Int Heart J ; 55(3): 278-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24814324

RESUMO

Endovascular therapy approaches for aortic aneurysm have lowered the mortality and morbidity rates even in high-risk patients; moreover, these approaches are applied in the management of aortic arch pathologies by transposition of the supra-aortic branches. We present the case of a 75-year-old female patient with situs inversus totalis on hemodialysis. The patient underwent off-pump aortic arch rerouting and thoracic endovascular aortic repair concomitant with coronary artery bypass grafting for distal aortic arch aneurysm and ischemic heart disease.


Assuntos
Aorta Torácica/cirurgia , Ponte de Artéria Coronária sem Circulação Extracorpórea/métodos , Procedimentos Endovasculares/métodos , Isquemia Miocárdica/cirurgia , Situs Inversus/cirurgia , Idoso , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Angiografia Coronária , Feminino , Seguimentos , Humanos , Isquemia Miocárdica/complicações , Isquemia Miocárdica/diagnóstico por imagem , Situs Inversus/complicações , Situs Inversus/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
Kyobu Geka ; 67(5): 367-70, 2014 May.
Artigo em Japonês | MEDLINE | ID: mdl-24917280

RESUMO

Recently, due to the progress in patient managements with antibiotics, the prognosis of the active phase infectious endocarditis (IE) has improved, but in some cases, urgent or emergent surgical treatment is inevitable because of the uncontrollable acute heart failure due to valve regurgitation, uncontrollable infection with circulatory collapse, or high embolization risk. We reviewed the outcomes of the 57 IE patients who underwent surgical treatment in our hospital from January, 2000 to April, 2012. Preoperative state including inflammatory responses, bacterial blood culture, antibiotic administration, and surgical procedures were examined. No statistical significances were detected in the mortalities between elective cases (n=43)and urgent or emergent cases (n=14). Totally, mortality was 5.3% including one case in prosthetic valve endocarditis, and was satisfactory.


Assuntos
Endocardite Bacteriana/cirurgia , Adulto , Idoso , Endocardite Bacteriana/microbiologia , Feminino , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
12.
Pathol Res Pract ; 260: 155425, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38964118

RESUMO

Diffuse large B-cell lymphoma (DLBCL) exhibits clinical, genetic, and immunohistochemical heterogeneity. However, the differences between primary extranodal or nodal DLBCL and double-expressor lymphoma (DEL), which is characterized by high MYC and BCL2 expression, remain unclear. This study aimed to elucidate the clinicopathological features, response to therapy, and clinical outcomes of primary extranodal (n=61) and nodal (n=128) DLBCL. Patients with primary nodal DLBCL had higher BCL2 expression than those with extranodal DLBCL (p=0.048), with high MYC expression and DEL as poor prognostic factors. Conversely, in patients with primary extranodal DLBCL, high BCL2 expression, low BCL6 expression, non-germinal center B-cell-like type, and DEL indicated poor prognosis. DEL was significantly associated with progression free survival and overall survival in patients with primary extranodal DLBCL (p=0.014 and p=0.021, respectively) but not in patients with primary nodal DLBCL (p=0.37 and p=0.084, respectively). Our findings highlight primary extranodal DEL as a strong adverse prognostic factor in DLBCL.

13.
JTCVS Open ; 18: 209-220, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38690440

RESUMO

Objectives: The complexity of aortic arch reconstruction due to diverse 3-dimensional geometrical abnormalities is a major challenge. This study introduces 3-dimensional printed tissue-engineered vascular grafts, which can fit patient-specific dimensions, optimize hemodynamics, exhibit antithrombotic and anti-infective properties, and accommodate growth. Methods: We procured cardiac magnetic resonance imaging with 4-dimensional flow for native porcine anatomy (n = 10), from which we designed tissue-engineered vascular grafts for the distal aortic arch, 4 weeks before surgery. An optimal shape of the curved vascular graft was designed using computer-aided design informed by computational fluid dynamics analysis. Grafts were manufactured and implanted into the distal aortic arch of porcine models, and postoperative cardiac magnetic resonance imaging data were collected. Pre- and postimplant hemodynamic data and histology were analyzed. Results: Postoperative magnetic resonance imaging of all pigs with 1:1 ratio of polycaprolactone and poly-L-lactide-co-ε-caprolactone demonstrated no specific dilatation or stenosis of the graft, revealing a positive growth trend in the graft area from the day after surgery to 3 months later, with maintaining a similar shape. The peak wall shear stress of the polycaprolactone/poly-L-lactide-co-ε-caprolactone graft portion did not change significantly between the day after surgery and 3 months later. Immunohistochemistry showed endothelization and smooth muscle layer formation without calcification of the polycaprolactone/poly-L-lactide-co-ε-caprolactone graft. Conclusions: Our patient-specific polycaprolactone/poly-L-lactide-co-ε-caprolactone tissue-engineered vascular grafts demonstrated optimal anatomical fit maintaining ideal hemodynamics and neotissue formation in a porcine model. This study provides a proof of concept of patient-specific tissue-engineered vascular grafts for aortic arch reconstruction.

14.
J Biol Chem ; 287(34): 28697-704, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22773838

RESUMO

Elongation factor G (EF-G), a key protein in translational elongation, is known to be particularly susceptible to oxidation in Escherichia coli. However, neither the mechanism of the oxidation of EF-G nor the influence of its oxidation on translation is fully understood. In the present study, we investigated the effects of oxidants on the chemical properties and function of EF-G using a translation system in vitro derived from E. coli. Treatment of EF-G with 0.5 mM H(2)O(2) resulted in the complete loss of translational activity. The inactivation of EF-G by H(2)O(2) was attributable to the oxidation of two specific cysteine residues, namely, Cys(114) and Cys(266), and subsequent formation of an intramolecular disulfide bond. Replacement of Cys(114) by serine rendered EF-G insensitive to oxidation and inactivation by H(2)O(2). Furthermore, generation of the translation system in vitro with the mutated EF-G protected the entire translation system from oxidation, suggesting that EF-G might be a primary target of oxidation within the translation system. Oxidized EF-G was reactivated via reduction of the disulfide bond by thioredoxin, a ubiquitous protein that mediates dithiol-disulfide exchange. Our observations indicate that the translational machinery in E. coli is regulated, in part, by the redox state of EF-G, which might depend on the balance between the supply of reducing power and the degree of oxidative stress.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Estresse Oxidativo/fisiologia , Fator G para Elongação de Peptídeos/metabolismo , Biossíntese de Proteínas/fisiologia , Cisteína/genética , Cisteína/metabolismo , Dissulfetos/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fator G para Elongação de Peptídeos/genética , Biossíntese de Proteínas/efeitos dos fármacos
15.
Photosynth Res ; 117(1-3): 509-15, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23456267

RESUMO

The repair of photosystem II (PSII) after photodamage is particularly sensitive to reactive oxygen species-such as H2O2, which is abundantly produced during the photoinhibition of PSII. In the present study, we generated a transformant of the cyanobacterium Synechococcus elongatus PCC 7942 that expressed a highly active catalase, VktA, which is derived from a facultatively psychrophilic bacterium Vibrio rumoiensis, and examined the effect of expression of VktA on the photoinhibition of PSII. The activity of PSII in transformed cells declined much more slowly than in wild-type cells when cells were exposed to strong light in the presence of H2O2. However, the rate of photodamage to PSII, as monitored in the presence of chloramphenicol, was the same in the two lines of cells, suggesting that the repair of PSII was protected by the expression of VktA. The de novo synthesis of the D1 protein, which is required for the repair of PSII, was activated in transformed cells under the same stress conditions. Similar protection of the repair of PSII in transformed cells was also observed under strong light at a relatively low temperature. Thus, the expression of the highly active catalase mitigates photoinhibition of PSII by protecting protein synthesis against damage by H2O2 with subsequent enhancement of the repair of PSII.


Assuntos
Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Processos Fotoquímicos , Complexo de Proteína do Fotossistema II/metabolismo , Synechococcus/enzimologia , Genes Bacterianos/genética , Peróxido de Hidrogênio/farmacologia , Processos Fotoquímicos/efeitos dos fármacos , Synechococcus/efeitos dos fármacos , Synechococcus/genética , Vibrio/enzimologia , Vibrio/genética
16.
Int Heart J ; 54(1): 11-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23428918

RESUMO

Together with aging of the Japanese population, aortic valve replacement (AVR) for aortic stenosis (AS) is now becoming more and more common in the elderly. When the aortic annulus is too small to allow an adequate sized prosthetic valve, aortic root enlargement is required to avoid prosthesis-patient mismatch (PPM). However, age-related comorbidities including aortic root calcification bring significant risk in performing aortic root enlargement. In the present study, 40 patients aged 75 years or more who underwent AVR for AS were reviewed to determine whether moderate PPM has a negative impact on the long-term results. Operative mortality occurred in 2 patients (5%) and moderate PPM occurred in 8 patients. There was no significant difference in survival between cases with and without PPM (P = 0.87). Both aortic pressure gradient (PG) and left ventricular mass index (LVMI) measured by echocardiography were signifi cantly decreased in patients with and without PPM. Reduction of PG was significantly greater in patients with PPM than without PPM (P = 0.02). Reduction of LVMI was not different between the groups (P = 0.58). Moderate PPM did not negatively influence survival or reduction of PG or LVMI in patients aged 75 years or older who underwent AVR for AS.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica , Calcinose/patologia , Implante de Prótese de Valva Cardíaca , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/fisiopatologia , Pressão Arterial , Ecocardiografia , Análise de Falha de Equipamento , Feminino , Próteses Valvulares Cardíacas/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/mortalidade , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Japão/epidemiologia , Masculino , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Ajuste de Prótese/efeitos adversos , Ajuste de Prótese/métodos , Risco Ajustado , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo
17.
Cureus ; 15(5): e38368, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37265894

RESUMO

A 29-year-old woman was admitted with a diagnosis of ischemic enteritis. She had a coronavirus disease 2019 (COVID-19) infection four weeks before this visit and continued to experience a cough. Four months before, she received the third COVID-19 vaccine. Chest computer tomography revealed scattered ground-glass opacities in both upper lobes. Based on abnormalities in chest imaging, eosinophilia, and a high level of fractional exhaled nitric oxide, she was diagnosed with eosinophilic lower airway inflammation due to COVID-19. Since the visit, the patient had an intermittent fever and no radiological improvement, so systemic corticosteroid treatment was initiated, and the symptoms and clinical findings improved. Clinicians should know the potential association between COVID-19 and eosinophilic lower airway inflammation, which may still occur despite multiple vaccinations.

18.
Mutat Res ; 827: 111835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37562181

RESUMO

New, useful microorganism resources have been generated by ionizing radiation breeding technology. However, the mutagenic effects of ionizing radiation on microorganisms have not been systematically clarified. For a deeper understanding and characterization of ionizing radiation-induced mutations in microorganisms, we investigated the lethal effects of seven different linear energy transfer (LET) radiations based on the survival fraction (SF) and whole-genome sequencing analysis of the mutagenic effects of a dose resulting in an SF of around 1% in Bacillus subtilis spores. Consequently, the lower LET radiations (gamma [surface LET: 0.2 keV/µm] and 4He2+ [24 keV/µm]) showed low lethality and high mutation frequency (MF), resulting in the major induction of single-base substitutions. Whereas higher LET radiations (12C5+ [156 keV/µm] and 12C6+ [179 keV/µm]) showed high lethality and low MF, resulting in the preferential induction of deletion mutations. In addition, 12C6+ (111) ion beams likely possess characteristics of both low- and high-LET radiations simultaneously. A decrease in the relative biological effectiveness and an evaluation of the inactivation cross section indicated that 20Ne8+ (468 keV/µm) and 40Ar13+ (2214 keV/µm) ion beams had overkill effects. In conclusion, in the mutation breeding of microorganisms, it should be possible to regulate the proportions, types, and frequencies of induced mutations by selecting an ionizing radiation of an appropriate LET in accordance with the intended purpose.


Assuntos
Bacillus subtilis , Mutagênicos , Bacillus subtilis/genética , Relação Dose-Resposta à Radiação , Transferência Linear de Energia , Esporos Bacterianos/genética
19.
Biochim Biophys Acta ; 1807(2): 236-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21074511

RESUMO

α-Tocopherol is a lipophilic antioxidant that is an efficient scavenger of singlet oxygen. We investigated the role of α-tocopherol in the protection of photosystem II (PSII) from photoinhibition using a mutant of the cyanobacterium Synechocystis sp. PCC 6803 that is deficient in the biosynthesis of α-tocopherol. The activity of PSII in mutant cells was more sensitive to inactivation by strong light than that in wild-type cells, indicating that lack of α-tocopherol enhances the extent of photoinhibition. However, the rate of photodamage to PSII, as measured in the presence of chloramphenicol, which blocks the repair of PSII, did not differ between the two lines of cells. By contrast, the repair of PSII from photodamage was suppressed in mutant cells. Addition of α-tocopherol to cultures of mutant cells returned the extent of photoinhibition to that in wild-type cells, without any effect on photodamage. The synthesis de novo of various proteins, including the D1 protein that plays a central role in the repair of PSII, was suppressed in mutant cells under strong light. These observations suggest that α-tocopherol promotes the repair of photodamaged PSII by protecting the synthesis de novo of the proteins that are required for recovery from inhibition by singlet oxygen.


Assuntos
Antioxidantes/metabolismo , Luz , Complexo de Proteína do Fotossistema II/metabolismo , Synechocystis/metabolismo , alfa-Tocoferol/metabolismo , Oxigênio Singlete/metabolismo , Synechocystis/genética
20.
Extremophiles ; 16(6): 871-82, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22996829

RESUMO

We investigated the protein folding mechanism of the GroEL system of a psychrophilic bacterium, Colwellia psychrerythraea 34H. The amount of mRNA of the groESL operon of C. psychrerythraea was increased about 6-fold after a temperature upshift from 8 to 18 °C for 30 min, suggesting that this temperature causes heat stress in this bacterium. A σ(32)-type promoter was found upstream of the groESL, suggesting that the C. psychrerythraea groESL is regulated by the σ(32) system, like the groESL in E. coli. The maximum ATPase and CTPase activities of CpGroEL were observed at 45 and 35 °C, respectively, which are much higher than the growth temperatures of C. psychrerythraea. We found that the refolding activity of the CpGroEL system in the presence of ATP is lower than that in the presence of CTP. This suggests that ATP is not the optimum energy source of the CpGroEL system. Analyses for the interaction of CpGroEL-CpGroES revealed that CTP could weaken this interaction, resulting in effective refolding function of the CpGroEL system. From these findings, we consider that the CpGroEL system possesses an energy-saving mechanism for avoiding excess consumption of ATP to ensure growth in a low-temperature environment.


Assuntos
Alteromonadaceae/metabolismo , Proteínas de Bactérias/metabolismo , Chaperonina 60/metabolismo , Dobramento de Proteína , Trifosfato de Adenosina/metabolismo , Alteromonadaceae/enzimologia , Alteromonadaceae/genética , Animais , Proteínas de Bactérias/genética , Chaperonina 10/genética , Chaperonina 10/metabolismo , Chaperonina 60/genética , Citidina Trifosfato/metabolismo , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Malato Desidrogenase/química , Óperon , Regiões Promotoras Genéticas , Desnaturação Proteica , RNA Mensageiro/biossíntese , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Temperatura , Transcrição Gênica , alfa-Glucosidases/química
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