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1.
Am J Emerg Med ; 70: 208.e5-208.e7, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37423820

RESUMEN

Patients with infectious diseases including sepsis can develop ST segment changes on an electrocardiogram (ECG) in the absence of coronary artery disease. However, ST elevation with "reciprocal ST segment depression (RSTD)", which is recognized as a specific finding for ST-elevated myocardial infarction, is rare in such patients. Although a small number of cases have reported ST-segment elevation in gastritis, cholecystitis, and sepsis, regardless of coronary artery disease, none presented with reciprocal changes. Here, we describe a rare case of a patient with emphysematous pyelonephritis complicating septic shock who developed ST elevation accompanied by reciprocal changes with no coronary occlusion. Emergency physicians should consider the possibility of acute coronary syndrome mimicking, and choose non-invasive diagnostic procedures when investigating the causes of ECG abnormalities associated with critically ill patients.


Asunto(s)
Síndrome Coronario Agudo , Enfermedad de la Arteria Coronaria , Pielonefritis , Infarto del Miocardio con Elevación del ST , Sepsis , Humanos , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/diagnóstico , Infarto del Miocardio con Elevación del ST/diagnóstico , Electrocardiografía/métodos , Arritmias Cardíacas , Pielonefritis/complicaciones , Pielonefritis/diagnóstico , Angiografía Coronaria
2.
BMC Anesthesiol ; 22(1): 205, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35787789

RESUMEN

BACKGROUND: Although peripherally inserted central catheters (PICCs) have been widely used, they have not been frequently used in anesthesia practice. The central venous pressure measured via PICCs are reportedly as accurate as that measured via central venous catheters (CVCs), but the findings concerning rapid infusion are unclear. This study examined whether or not pressure-resistant PICCs could be used for rapid fluid infusion.  METHODS: The in-line pressure was measured in similar-sized double-lumen catheters-4-Fr PICC (55, 45 and 35 cm) and 17-G CVC (20 and 13 cm)-at flow rates of saline decided using a roller pump system. We also examined the flow rate at an in-line pressure of 300 mmHg, which is the critical pressure at which hemolysis is considered to occur during blood transfusion. RESULTS: The pressure-resistant PICCs obtained a high flow rate similar to that of CVCs, but the in-line pressures increased in proportion to the flow rate and catheter length. Flow rates at an intra-circuit pressure of 300 mmHg were not significantly different between the 45-cm PICC and 20-cm CVC. CONCLUSION: Pressure-resistant PICCs can be used for rapid fluid infusion.


Asunto(s)
Cateterismo Venoso Central , Cateterismo Periférico , Catéteres Venosos Centrales , Presión Venosa Central
3.
J Infect Chemother ; 26(12): 1319-1323, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32893123

RESUMEN

The number of people infected with severe acute respiratory syndrome coronavirus 2 is increasing globally, and some patients have a fatal clinical course. In light of this situation, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic on March 11, 2020. While clinical studies and basic research on a treatment for COVID-19 are ongoing around the world, no treatment has yet been proven to be effective. Several clinical studies have demonstrated the efficacy of chloroquine phosphate and nafamostat mesylate with COVID-19. Here, we report the case of a Japanese patient with COVID-19 with severe respiratory failure who improved following the administration of hydroxychloroquine and continuous hemodiafiltlation with nafamostat mesylate. Hence, hydroxychloroquine with nafamostat mesylate might be a treatment option for severe COVID-19.


Asunto(s)
Infecciones por Coronavirus/tratamiento farmacológico , Guanidinas/administración & dosificación , Hemodiafiltración/métodos , Hidroxicloroquina/administración & dosificación , Neumonía Viral/tratamiento farmacológico , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Antivirales/administración & dosificación , Benzamidinas , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/terapia , Combinación de Medicamentos , Humanos , Japón , Lopinavir/administración & dosificación , Masculino , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/terapia , Insuficiencia Respiratoria/complicaciones , Ritonavir/administración & dosificación , SARS-CoV-2 , Resultado del Tratamiento , Tratamiento Farmacológico de COVID-19
4.
Pediatr Crit Care Med ; 20(8): e366-e371, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31162371

RESUMEN

OBJECTIVES: To characterize the real size and morphology of tracheas in childhood for the optimal selection of endotracheal tube. DESIGN: A retrospective cohort study of pediatric patients who received CT scan of the cervical spine from July 2011 to March 2018. Cross-sectional CT images vertical to trachea were reconstructed and the accurate tracheal diameters were measured. The validity of the traditional age-based formula for predicting the endotracheal tube size was assessed for the best fit to trachea. SETTING: Tertiary Emergency and Critical Care Center of Kyushu University Hospital. PATIENTS: Children, who are 1 month to 15 years old, received CT scan of the cervical spine. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We enrolled 86 children with median age of 53 months. The cross-sectional shape of pediatric trachea was circular at the cricoid level and elliptical at the infraglottic level. The narrowest part of pediatric trachea was the transverse diameter at the infraglottic level at any age. Significant positive correlation between age and the narrowest diameter was observed. When compared the transverse diameter at the infraglottic level with the outer diameter of endotracheal tubes, uncuffed endotracheal tubes selection based on the traditional age-based formula ran a significant risk of oversized endotracheal intubation until 10 years old compared with cuffed endotracheal tubes selection (60.0% vs 23.8%; p < 0.05). CONCLUSIONS: These findings indicate the safety and efficacy of cuffed endotracheal tubes in infants and children and the reconsideration for the airway management in pediatric anesthesia and intensive care.


Asunto(s)
Intubación Intratraqueal/normas , Tráquea/anatomía & histología , Adolescente , Factores de Edad , Médula Cervical/diagnóstico por imagen , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Tráquea/diagnóstico por imagen
5.
Chem Pharm Bull (Tokyo) ; 66(7): 732-740, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29962457

RESUMEN

Three 2-fluoroacetonylbenzoxazole ligands 1a-c and their new Zn(II) complexes 2a-c have been synthesized. In addition, syntheses of new metal [Mg(II), Ni(II), Cu(II), Pd(II), and Ag(I)] complexes from 1a have been also described. The molecular and crystal structures of six metal complexes 2b and 2d-h were determined by single-crystal X-ray diffraction analyses. Their antibacterial activities against six Gram-positive and six Gram-negative bacteria were evaluated by minimum inhibitory concentrations (MIC), which were compared with those of appropriate antibiotics and silver nitrate. The results indicate that some metal compounds have more antibacterial effects in comparison with free ligands and have preferred antibacterial activities that may have potential pharmaceutical applications. Noticeably, the Ag(I) complex 2h exhibited low MIC value of 0.7 µM against Pseudomonas aeruginosa, which was even superior to the reference drug, Norfloxacin with that of 1.5 µM. Against P. aeruginosa, 2h is bacteriostatic, exerts the cell surface damage observed by scanning electron microscopy (SEM) and is less likely to develop resistance. The new 2h has been found to display effective antimicrobial activity against a series of bacteria.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Benzoxazoles/química , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos/química , Benzoxazoles/metabolismo , Relación Dosis-Respuesta a Droga , Ligandos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Compuestos Organometálicos/química , Relación Estructura-Actividad
6.
Biochem Biophys Res Commun ; 493(3): 1267-1272, 2017 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-28962862

RESUMEN

The pathogenesis and infectivity of Gram-positive bacteria are mediated by many surface proteins that are covalently attached to peptidoglycans of the cell wall. The covalent attachment of these proteins is catalyzed by sortases (Srts), a family of cysteine transpeptidases, which are classified into six classes, A - F, based on their amino acid sequences and biological roles. Clostridium perfringens, one of the pathogenic clostridial species, has a class B sortase (CpSrtB) with 249 amino acid residues. X-ray structures of CpSrtB and its inactive mutant form were determined at 2.2 Å and 1.8 Å resolutions, respectively. CpSrtB adopts a typical sortase-protein fold, and has a unique substrate-binding groove formed by three ß-strands and two helices creating the sidewalls of the groove. The position of the catalytic Cys232 of CpSrtB is significantly different from those commonly found in Srts structures. The modeling study of the CpSrtB/peptide complex suggested that the position of Cys232 found in CpSrtB is preferable for the catalytic reaction to occur. Structural comparison with other class B sortases demonstrated that the catalytic site likely converts between two forms. The movement of Cys232 between the two forms may help His136 deprotonate Cys232 to be activated as a thiolate, which may the catalytic Cys-activated mechanism for Srts.


Asunto(s)
Aminoaciltransferasas/química , Aminoaciltransferasas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Clostridium perfringens/enzimología , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/metabolismo , Sustitución de Aminoácidos , Aminoaciltransferasas/genética , Proteínas Bacterianas/genética , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Cisteína/química , Cisteína/metabolismo , Cisteína Endopeptidasas/genética , Modelos Moleculares , Mutación , Conformación Proteica
7.
Am J Emerg Med ; 35(11): 1790.e3-1790.e5, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28844532

RESUMEN

Esophageal perforation due to blunt trauma is a rare clinical condition, and the diagnosis is often difficult because patients have few specific symptoms. Delayed diagnosis may result in a fatal clinical course due to mediastinitis and subsequent sepsis. In this article, we describe a 26-year-old man with esophageal perforation due to blunt chest trauma resulting from a motor vehicle accident. Because a severe disturbance of consciousness masked the patient's trauma-induced thoracic symptoms, we required 11h to diagnose the esophageal perforation. Therefore, the patient developed septic shock due to mediastinitis. However, his subsequent clinical course was good because of prompt combined therapy involving surgical repair and medical treatment after the diagnosis.


Asunto(s)
Accidentes de Tránsito , Perforación del Esófago/etiología , Mediastinitis/etiología , Choque Séptico/etiología , Traumatismos Torácicos/complicaciones , Heridas no Penetrantes/complicaciones , Adulto , Coma/complicaciones , Diagnóstico Tardío , Perforación del Esófago/diagnóstico , Perforación del Esófago/cirugía , Esofagoscopía , Escala de Coma de Glasgow , Hemotórax/diagnóstico por imagen , Hemotórax/etiología , Humanos , Masculino , Enfisema Mediastínico/diagnóstico por imagen , Enfisema Mediastínico/etiología , Mediastinitis/diagnóstico por imagen , Neumotórax/complicaciones , Neumotórax/diagnóstico por imagen , Radiografía Torácica , Enfisema Subcutáneo/diagnóstico por imagen , Enfisema Subcutáneo/etiología , Tomografía Computarizada por Rayos X
8.
Am J Emerg Med ; 35(12): 1836-1838, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28633904

RESUMEN

BACKGROUND AND PURPOSE: Accurate diagnosis of acute aortic dissection (AAD) is sometimes difficult because of accompanying central nervous system (CNS) symptoms. The purpose of this study was to investigate the clinical characteristics of Type A AAD (TAAAD) with CNS symptoms. METHODS: We retrospectively reviewed the medical records of 8403 patients ambulanced to our emergency and critical care center between April 2009 and May 2014. RESULTS: We identified 59 TAAAD patients for the analysis (mean age, 67.3±10.5years; 37 (62.0%) male). Eleven patients (18.6%) presented CNS symptoms at the onset of TAAAD, and these patients complained less frequently of typical chest and back pain than those without CNS symptoms (p<0.0001). Initial systolic and diastolic blood pressure were lower (p=0.003, and p=0.049, respectively) and involvement of the supra-aortic artery was more frequent in patients with CNS symptoms (p<0.0001). CONCLUSION: Because CNS symptom can mask chest and back pain caused by TAAAD, physicians should always consider the possibility of TAAAD in patients with CNS symptoms in emergency medicine settings.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico por imagen , Disección Aórtica/diagnóstico por imagen , Enfermedades del Sistema Nervioso Central/diagnóstico por imagen , Servicio de Urgencia en Hospital , Tomografía Computarizada por Rayos X , Anciano , Disección Aórtica/epidemiología , Disección Aórtica/fisiopatología , Aneurisma de la Aorta Torácica/epidemiología , Aneurisma de la Aorta Torácica/fisiopatología , Presión Sanguínea , Enfermedades del Sistema Nervioso Central/complicaciones , Enfermedades del Sistema Nervioso Central/fisiopatología , Medios de Contraste , Femenino , Humanos , Japón/epidemiología , Masculino , Estudios Retrospectivos
9.
Chem Pharm Bull (Tokyo) ; 65(9): 878-882, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28867716

RESUMEN

Mousouchiku extract is prepared from the bamboo-sheath of Phyllostachys heterocycla MITF. (Poaceae), and is registered as a food manufacturing agent in the List of Existing Food Additives in Japan. This study describes the chromatographic evaluation of characteristic components of this extract to obtain the chemical data needed for standardized specifications. We isolated 12 known compounds from this extract: 5-hydroxymethyl-2-furfural, 4-hydroxybenzoic acid, trans-p-coumaric acid, trans-ferulic acid, N,N'-diferuloylputrescine, 4'-hydroxypropiophenone, ß-arbutin, tachioside, isotachioside, 3,4'-dihydroxypropiophenone 3-O-glucoside, koaburaside, and (+)-lyoniresinol 9'-O-glucoside. Moreover, a new propiophenone glycoside, propiophenone 4'-O-(6-ß-D-xylosyl)-ß-D-glucoside (propiophenone 4'-O-primeveroside), was isolated. The structure of each isolated compound was elucidated based on NMR and MS data or direct HPLC comparisons with authentic samples. Among the isolates, (+)-lyoniresinol 9'-O-glucoside was found to be the major ingredients of the extract as observed using HPLC analysis. However, 2,6-dimethoxy-1,4-benzoquinone, which is considered the main constituent of mousouchiku extract, was only detected as a trace constituent and not isolated in this study.


Asunto(s)
Aditivos Alimentarios/química , Fenoles/química , Poaceae/química , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Cromatografía Líquida de Alta Presión , Escherichia coli/efectos de los fármacos , Aditivos Alimentarios/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Fenoles/aislamiento & purificación , Fenoles/farmacología , Extractos Vegetales/química , Poaceae/metabolismo , Staphylococcus aureus/efectos de los fármacos
10.
Chem Pharm Bull (Tokyo) ; 65(4): 365-372, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28381677

RESUMEN

In this report, we describe a new method for the synthesis of densely functionalized 2(1H)-pyrazinones. Treatment of mesoionic 1,3-oxazolium-5-olates with carbanions derived from activated methylene isocyanides (p-toluenesulfonylmethyl isocyanide (TosMIC) and ethyl isocyanoacetate) causes a novel ring transformation affording 2(1H)-pyrazinones in moderate to high yields. The cytotoxicity and antibacterial activity of some of the obtained products were studied and some of the products exhibited tumor-specific cytotoxicity.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Técnicas de Química Sintética , Pirazinas/síntesis química , Pirazinas/farmacología , Antibacterianos/química , Antineoplásicos/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirazinas/química , Relación Estructura-Actividad
12.
Mol Microbiol ; 92(2): 326-37, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24674022

RESUMEN

Gram-positive bacteria possess a thick cell wall composed of a mesh polymer of peptidoglycans, which provides physical protection. Endolysins encoded by phages infecting bacteria can hydrolyse peptidoglycans in the bacterial cell wall, killing the host bacteria immediately. The endolysin (Psm) encoded by episomal phage phiSM101 of enterotoxigenic Clostridium perfringens type A strain SM101 exhibits potent lytic activity towards most strains of Clostridium perfringens. Psm has an N-terminal catalytic domain highly homologous to N-acetylmuramidases belonging to the glycoside hydrolase 25 family, and C-terminal tandem repeated bacterial Src homology 3 (SH3_3) domains as the cell wall-binding domain. The X-ray structure of full-length Psm and a catalytic domain of Psm in complex with N-acetylglucosamine were determined to elucidate the catalytic reaction and cell wall recognition mechanisms of Psm. The results showed that Psm may have adopted a neighbouring-group mechanism for the catalytic hydrolysing reaction in which the N-acetyl carbonyl group of the substrate was involved in the formation of an oxazolinium ion intermediate. Based on structural comparisons with other endolysins and a modelling study, we proposed that tandem repeated SH3_3 domains of Psm recognized the peptide side-chains of peptidoglycans to assist the catalytic domain hydrolysing the glycan backbone.


Asunto(s)
Bacteriófagos/enzimología , Endopeptidasas/química , Acetilglucosamina/metabolismo , Clostridium perfringens/virología , Modelos Moleculares , Unión Proteica , Conformación Proteica
13.
Am J Physiol Heart Circ Physiol ; 306(7): H954-62, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24531811

RESUMEN

We have previously shown decreased pulmonary lymph flow in our lamb model of chronically increased pulmonary blood flow, created by the in utero placement of an 8-mm aortopulmonary shunt. The purpose of this study was to test the hypothesis that abnormal lymphatic function in shunt lambs is due to impaired lymphatic endothelial nitric oxide (NO)-cGMP signaling resulting in increased lymphatic vascular constriction and/or impaired relaxation. Thoracic duct rings were isolated from 4-wk-old shunt (n = 7) and normal (n = 7) lambs to determine length-tension properties, vascular reactivity, and endothelial NO synthase protein. At baseline, shunt thoracic duct rings had 2.6-fold higher peak to peak tension and a 2-fold increase in the strength of contractions compared with normal rings (P < 0.05). In response to norepinephrine, shunt thoracic duct rings had a 2.4-fold increase in vascular tone compared with normal rings (P < 0.05) and impaired relaxation in response to the endothelium-dependent dilator acetylcholine (63% vs. 13%, P < 0.05). In vivo, inhaled NO (40 ppm) increased pulmonary lymph flow (normalized for resistance) ∼1.5-fold in both normal and shunt lambs (P < 0.05). Inhaled NO exposure increased bioavailable NO [nitrite/nitrate (NOx); ∼2.5-fold in normal lambs and ∼3.4-fold in shunt lambs] and cGMP (∼2.5-fold in both) in the pulmonary lymph effluent (P < 0.05). Chronic exposure to increased pulmonary blood flow is associated with pulmonary lymphatic endothelial injury that disrupts NO-cGMP signaling, leading to increased resting vasoconstriction, increased maximal strength of contraction, and impaired endothelium-dependent relaxation. Inhaled NO increases pulmonary lymph NOx and cGMP levels and pulmonary lymph flow in normal and shunt lambs. Therapies that augment NO-cGMP signaling within the lymphatic system may provide benefits, warranting further study.


Asunto(s)
Cardiopatías Congénitas/metabolismo , Contracción Muscular , Relajación Muscular , Óxido Nítrico/metabolismo , Arteria Pulmonar/fisiopatología , Circulación Pulmonar , Transducción de Señal , Conducto Torácico/metabolismo , Administración por Inhalación , Animales , Velocidad del Flujo Sanguíneo , GMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Endotelio Linfático/metabolismo , Endotelio Linfático/fisiopatología , Cardiopatías Congénitas/fisiopatología , Linfa/metabolismo , Contracción Muscular/efectos de los fármacos , Relajación Muscular/efectos de los fármacos , Óxido Nítrico/administración & dosificación , Donantes de Óxido Nítrico/farmacología , Norepinefrina/farmacología , S-Nitroso-N-Acetilpenicilamina/farmacología , Ovinos , Transducción de Señal/efectos de los fármacos , Conducto Torácico/efectos de los fármacos , Conducto Torácico/fisiopatología , Factores de Tiempo
14.
Am J Physiol Heart Circ Physiol ; 306(8): H1222-30, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24561861

RESUMEN

Patients with pulmonary hypertension associated with congenital heart disease survive longer with preserved right ventricular (RV) function compared with those with primary pulmonary hypertension. The purpose of this study was to test the hypothesis that superior RV performance can be demonstrated, at baseline and when challenged with increased RV afterload, in lambs with chronic left-to-right cardiac shunts compared with control lambs. A shunt was placed between the pulmonary artery and the aorta in fetal lambs (shunt). RV pressure-volume loops were obtained 4 wk after delivery in shunt and control lambs, before and after increased afterload was applied using pulmonary artery banding (PAB). Baseline stroke volume (8.7 ± 1.8 vs. 15.8 ± 2.7 ml, P = 0.04) and cardiac index (73.0 ± 4.0 vs. 159.2 ± 25.1 ml·min(-1)·kg(-1), P = 0.02) were greater in shunts. After PAB, there was no difference in the change in cardiac index (relative to baseline) between groups; however, heart rate (HR) was greater in controls (168 ± 7.3 vs. 138 ± 6.6 beats/min, P = 0.01), and end-systolic elastance (Ees) was greater in shunts (2.63 vs. 1.31 × baseline, P = 0.02). Control lambs showed decreased mechanical efficiency (71% baseline) compared with shunts. With acute afterload challenge, both controls and shunts maintained cardiac output; however, this was via maladaptive responses in controls, while shunts maintained mechanical efficiency and increased contractility via a proposed enhanced Anrep effect-the second, slow inotropic response in the biphasic ventricular response to increased afterload, a novel finding in the RV. The mechanisms related to these physiological differences may have important therapeutic implications.


Asunto(s)
Cardiopatías Congénitas/fisiopatología , Ventrículos Cardíacos/fisiopatología , Anastomosis Quirúrgica , Animales , Aorta/cirugía , Cardiomegalia , Modelos Animales de Enfermedad , Femenino , Hipertensión Pulmonar/fisiopatología , Contracción Miocárdica , Embarazo , Arteria Pulmonar/cirugía , Ovinos , Volumen Sistólico , Función Ventricular Derecha , Presión Ventricular
15.
Biosci Biotechnol Biochem ; 78(10): 1777-87, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25273145

RESUMEN

We found that, under iron-limiting conditions, Aeromonas hydrophila ATCC 7966(T) could utilize the xenosiderophore desferrioxamine B (DFOB) for growth by inducing the expression of its own outer membrane receptor. Two consecutive genes, desR and desA, were selected as candidates involved in DFOB utilization. The presence of the ferric-uptake regulator boxes in their promoters suggested that these genes are under iron-dependent regulation. Mutation of desA, a gene that encodes the outer membrane receptor of ferrioxamine B, disrupted the growth of the amonabactin-deficient mutant in the presence of DFOB. ß-Galactosidase reporter assays and reverse transcriptase-quantitative PCR demonstrated that desR, a gene that encodes an AraC-like regulator homolog is required for the induction of desA transcription in the presence of DFOB and under iron-limiting conditions. The functions of desA and desR were analyzed using complementation experiments. Our data provided evidence that DesA is powered primarily by the TonB2 system.


Asunto(s)
Aeromonas hydrophila/genética , Aeromonas hydrophila/metabolismo , Factor de Transcripción de AraC/genética , Factor de Transcripción de AraC/metabolismo , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Deferoxamina/metabolismo , Compuestos Férricos/metabolismo , Secuencia de Aminoácidos , Factor de Transcripción de AraC/química , Metabolismo Energético , Hierro/metabolismo , Familia de Multigenes/genética , Operón/genética , Fenotipo , Eliminación de Secuencia , Especificidad por Sustrato , Transcripción Genética
16.
Cureus ; 16(5): e59594, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38826999

RESUMEN

We report the successful anesthetic management of laparoscopic surgery in a 21-year-old female patient with Fontan circulation. A preoperative careful review of cardiac catheterization results helped assess the risk of the surgery and implement anesthetic management. Intraoperative management focused on minimizing the impact on pulmonary vascular resistance and venous return by optimizing ventilation and applying lower pneumoperitoneum pressure without tilting the position. Milrinone was administered to reduce pulmonary vascular resistance and provide inotropic support with minimally invasive monitoring. The patient remained stable throughout the procedure without complications. This case highlights the importance of thorough preoperative assessment, individualized intraoperative management, and collaboration with the surgical team when caring for adult Fontan patients undergoing laparoscopic surgery.

17.
J Bacteriol ; 195(16): 3692-703, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23772063

RESUMEN

High-affinity iron acquisition in Vibrio parahaemolyticus is mediated by the cognate siderophore vibrioferrin. We have previously reported that the vibrioferrin biosynthesis operon (pvsOp) is regulated at the transcriptional level by the iron-responsive repressor Fur (T. Tanabe, T. Funahashi, H. Nakao, S. Miyoshi, S. Shinoda, and S. Yamamoto, J. Bacteriol. 185:6938-6949, 2003). In this study, we identified the Fur-regulated small RNA RyhB and the RNA chaperone Hfq protein as additional regulatory proteins of vibrioferrin biosynthesis. We found that vibrioferrin production was greatly impaired in both the ryhB and hfq deletion mutants, and a TargetRNA search (http://snowwhite.wellesley.edu/targetRNA/index2.html) revealed that the 5'-untranslated region of pvsOp mRNA (pvsOp 5'-UTR) contains a potential base-pairing region required for the formation of the RyhB-pvsOp 5'-UTR duplex. An electrophoresis mobility shift assay indicated that RyhB can directly bind to the pvsOp 5'-UTR with the aid of Hfq. Rifampin chase experiments indicated that the half-life of pvsOp mRNA in the ryhB and hfq mutants was approximately 3-fold shorter than that in the parental strain, suggesting that both RyhB and Hfq are engaged in the stabilization of pvsOp mRNA. Chrome azurol S assays followed by electrophoresis mobility shift assays and rifampin chase experiments carried out for mutant strains indicated that base pairing between RyhB and the pvsOp 5'-UTR results in an increase in the stability of pvsOp mRNA, thereby leading to the promotion of vibrioferrin production. It is unprecedented that RyhB confers increased stability on a polycistronic mRNA involved in siderophore biosynthesis as a direct target.


Asunto(s)
Proteínas Bacterianas/metabolismo , Citratos/metabolismo , Pirrolidinonas/metabolismo , ARN Bacteriano/metabolismo , ARN Mensajero/metabolismo , Vibrio parahaemolyticus/metabolismo , Regiones no Traducidas 5' , Proteínas Bacterianas/genética , Emparejamiento Base , Secuencia de Bases , Ensayo de Cambio de Movilidad Electroforética , Regulación Bacteriana de la Expresión Génica/fisiología , ARN Bacteriano/genética , ARN Mensajero/genética , Vibrio parahaemolyticus/genética
18.
Microbiology (Reading) ; 159(Pt 4): 678-690, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23378574

RESUMEN

Acinetobacter haemolyticus ATCC 17906(T) is known to produce the siderophore acinetoferrin under iron-limiting conditions. Here, we show that an operon consisting of eight consecutive genes, named acbABCD and actBCAD, participates in the biosynthesis and transport of acinetoferrin, respectively. Transcription of the operon was found to be iron-regulated by a putative Fur box located in the promoter region of the first gene, acbA. Homology searches suggest that acbABCD and actA encode enzyme proteins involved in acinetoferrin biosynthesis and an outer-membrane receptor for ferric acinetoferrin, respectively. Mutants defective in acbA and actA were unable to produce acinetoferrin or to express the ferric acinetoferrin receptor under iron-limiting conditions. These abilities were rescued by complementation of the mutants with native acbA and actA genes. Secondary structure analysis predicted that the products of actC and actD may be inner-membrane proteins with 12 membrane-spanning helices that belong to the major facilitator superfamily proteins. ActC showed homology to Sinorhizobium meliloti RhtX, which has been characterized as an inner-membrane importer for ferric rhizobactin 1021 structurally similar to acinetoferrin. Compared to the parental ATCC 17906(T) strain, the actD mutant displayed about a 35 % reduction in secretion of acinetoferrin, which was restored by complementation with actD, suggesting that ActD acts as an exporter of the siderophore. Finally, the actB product was significantly similar to hypothetical proteins in certain bacteria, in which genes encoding ActBCA homologues are arranged in the same order as in A. haemolyticus ATCC 17906(T). However, the function of ActB remains to be clarified.


Asunto(s)
Acinetobacter/metabolismo , Proteínas Bacterianas/metabolismo , Citratos/biosíntesis , Citratos/metabolismo , Regulación Bacteriana de la Expresión Génica , Ácidos Hidroxámicos/metabolismo , Familia de Multigenes , Acinetobacter/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Secuencia de Bases , Transporte Biológico/genética , Citratos/química , Genes Bacterianos , Ácidos Hidroxámicos/química , Hierro/metabolismo , Datos de Secuencia Molecular , Mutación , Análisis de Secuencia de ADN , Sideróforos/biosíntesis , Sideróforos/metabolismo
19.
Biosci Biotechnol Biochem ; 77(2): 353-60, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23391908

RESUMEN

Aeromonas hydrophila ATCC 7966(T) produces a catecholate siderophore amonabactin in response to iron starvation. In this study, we determined that this strain utilizes exogenously supplied enterobactin (Ent) for growth under iron-limiting conditions. A homology search of the A. hydrophila ATCC 7966(T) genomic sequence revealed the existence of a candidate gene encoding a protein homologous to Vibrio parahaemolyticus IrgA that functions as the outer membrane receptor for ferric Ent. SDS-PAGE showed induction of IrgA under iron-limiting conditions. The growth of the double mutant of irgA and entA (one of the amonabactin biosynthetic genes) was restored when it was complemented with irgA in the presence of Ent. Moreover, a growth assay of three isogenic tonB mutants indicated that the tonB2 system exclusively provides energy for IrgA to transport ferric Ent. Finally, reverse transcriptase-quantitative PCR revealed that the transcription of irgA and the TonB2 system cluster genes is iron-regulated, consistently with the presence of a predicted Fur box in the promoter region.


Asunto(s)
Aeromonas hydrophila/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Enterobactina/metabolismo , Regulación Bacteriana de la Expresión Génica , Hierro/metabolismo , Receptores de Superficie Celular/genética , Aeromonas hydrophila/metabolismo , Secuencia de Aminoácidos , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Transporte Biológico , Prueba de Complementación Genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Regiones Promotoras Genéticas , Receptores de Superficie Celular/metabolismo , Homología de Secuencia de Aminoácido , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/metabolismo
20.
Ther Hypothermia Temp Manag ; 13(2): 55-61, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35994019

RESUMEN

Avoiding redistributional hypothermia that decreases core temperature by 0.5-1.5°C within the 1st hour of surgery is difficult. The efficacy of prewarming using a forced-air warming (FAW) device with a lower-body blanket on redistribution hypothermia during epidural procedures have not been investigated. After ethics approval, 113 patients undergoing laparoscopic surgery under general anesthesia combined with epidural anesthesia were enrolled. Intervention (prewarming) group patients who were warmed from operating room entry, including during epidural anesthesia, was compared with the control group that was warmed from just before surgery started. In total, 104 patients (52, control; 52, prewarming) were analyzed. In the prewarming group, compared to the control group, the core temperature 20 minutes after anesthesia induction (36.9 ± 0.4 vs. 37.1 ± 0.4°C, p < 0.02) was significantly higher. The core temperature was higher in the prewarming group than in the control group until 3 hours after the surgery. In the prewarming group, compared to the control group, the core temperature-time integral below baseline till 180 minutes after surgery start (65.1 ± 64.0 vs. 8.1 ± 18.6°C/min, p < 0.0001) or 30 minutes after anesthesia induction (5.3 ± 6.2 vs. 2.0 ± 4.7°C/min, p < 0.0001) were significantly smaller. Postoperative shivering was comparable between the groups. Prewarming during epidural catheter insertion with a FAW device could safely prevent a core temperature decrease induced by redistribution or heat loss without additional preparation, effort, space, or time requirements.


Asunto(s)
Hipotermia Inducida , Hipotermia , Humanos , Temperatura Corporal , Regulación de la Temperatura Corporal , Hipotermia/prevención & control , Tiritona
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