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PURPOSE: Biliary atresia (BA) poses a persistent challenge characterized by ongoing liver inflammation and subsequent fibrosis even after the clearance of jaundice (COJ). This study aimed to evaluate the therapeutic potential of eicosapentaenoic acid (EPA) in alleviating liver inflammation and limiting fibrosis during the post-COJ phase of BA. METHODS: Among the BA patients undergoing laparoscopic Kasai portoenterostomy (lapKP) between December 2016 and October 2021, EPA (20-40 mg/kg/day) was administered orally to those whose parents consented. The study included patients from January 2014 to October 2021, classifying them into two groups: EPA-treated (Group E) and untreated (Group N). Their liver fibrosis and clinical course at 1 and 2 years post-lapKP were compared. RESULTS: Group E consisted of 25 patients, while Group N comprised 32 patients. Twenty-one patients in Group E and 25 patients in Group N achieved COJ (p = 0.74). Among jaundice-free patients at 1 and 2 years post-lapKP, Group E exhibited significantly lower M2BPGi levels and platelet counts, and Group E showed a significant reduction in Aminotransferase-to-Platelet Ratio Index (APRI) at 2 years post-lapKP. CONCLUSION: Although EPA administration did not improve COJ, it attenuated the progression of liver fibrosis during the 2 years following lapKP in jaundice-free patients. (200/200Words).
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Atresia Biliar , Progresión de la Enfermedad , Ácido Eicosapentaenoico , Cirrosis Hepática , Portoenterostomía Hepática , Humanos , Portoenterostomía Hepática/métodos , Ácido Eicosapentaenoico/uso terapéutico , Ácido Eicosapentaenoico/administración & dosificación , Masculino , Femenino , Atresia Biliar/cirugía , Lactante , Laparoscopía/métodos , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Resultado del Tratamiento , PreescolarRESUMEN
The Senhance® robotic system (Senhance [Asensus Surgical Inc., Naderhan, NC, USA]) is a new surgical assistive robot following the da Vinci Surgical System that has been demonstrated to be safe and efficacious. Herein, we report the first case series of pediatric pelvic surgery using Senhance. Two anorectoplasties and one rectal pull-through coloanal anastomosis for rectal stenosis were performed in three children (5-9 months, 7-9 kg) using a 10-mm three-dimensional (3D) 4K camera and 3 and 5 mm forceps operated with Senhance. None of the patients had intraoperative complications or a good postoperative course. Pediatric pelvic surgery with Senhance could be performed precisely and safely with a small body cavity. With its beautiful 3D images, motion of forceps with reduced tremor, and availability of 3-mm forceps, Senhance may be better suited for children compared with other models.
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Procedimientos Quirúrgicos Robotizados , Humanos , Procedimientos Quirúrgicos Robotizados/instrumentación , Lactante , Femenino , Masculino , Recto/cirugía , Anastomosis Quirúrgica/instrumentación , Constricción Patológica/cirugía , Canal Anal/cirugía , Enfermedades del Recto/cirugíaRESUMEN
PURPOSE: The prognostic factors of subsequent liver transplantation (LT) in patients with biliary atresia (BA) who presented with jaundice-free native liver survival were investigated. METHODS: This study retrospectively reviewed patients who underwent portoenterostomy (PE) for BA. Patients with jaundice-free native liver survival at 1 year postoperatively were divided into the autologous liver survivor and liver transplant recipient groups. Peri- and postoperative data were compared between the two groups. RESULTS: Among 97 patients with BA, 29 who received LT within 1 year after PE were excluded from the analysis. Further, 48 patients currently living with native liver and 20 who received LT after 1 year postoperatively were compared. Bile lake (BL) was the strongest risk factor of LT. The risk score was 2.38 ∗ B L s c o r e + 0.00466 ∗ T B A , and the area under the receiver operating characteristic curve was 0.83. Patients with BL and those without significantly differed in terms of the native liver survival rate. Patients with BL who presented with not only cholangitis but also gastrointestinal hemorrhage and hepatopulmonary syndrome received LT. CONCLUSION: BL can cause different pathologies. Moreover, it is an evident risk factor of subsequent LT in patients with BA who are living with native liver at 1 year after PE.
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Atresia Biliar , Trasplante de Hígado , Portoenterostomía Hepática , Humanos , Atresia Biliar/cirugía , Atresia Biliar/complicaciones , Atresia Biliar/mortalidad , Estudios Retrospectivos , Femenino , Masculino , Lactante , Factores de Riesgo , Portoenterostomía Hepática/métodos , Tasa de Supervivencia/tendencias , Bilis , Pronóstico , Preescolar , Ictericia/etiología , HígadoRESUMEN
PURPOSE: The surgical indication of thoracoscopic primary repair for esophageal atresia with tracheoesophageal fistula is under debate. The current study aimed to investigate the outcome of thoracoscopic primary repair for esophageal atresia with tracheoesophageal fistula in patients weighing < 2000 g and those who underwent emergency surgery at the age of 0 day. METHODS: The surgical outcomes were compared between patients weighing < 2000 g and those weighing > 2000 g at surgery and between patients who underwent surgery at the age of 0 day and those who underwent surgery at age ≥ 1 day. RESULTS: In total, 43 patients underwent thoracoscopic primary repair for esophageal atresia with tracheoesophageal fistula. The surgical outcomes according to body weight were similar. Patients who underwent surgery at the age of 0 day were more likely to develop anastomotic leakage than those who underwent surgery at the age of ≥ 1 day (2 vs. 0 case, p = 0.02). Anastomotic leakage was treated with conservative therapy. CONCLUSION: Thoracoscopic primary repair is safe and useful for esophageal atresia with tracheoesophageal fistula even in newborns weighing < 2000 g. However, emergency surgery at the age of 0 day should be cautiously performed due to the risk of anastomotic leakage.
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Atresia Esofágica , Toracoscopía , Fístula Traqueoesofágica , Humanos , Fístula Traqueoesofágica/cirugía , Fístula Traqueoesofágica/complicaciones , Atresia Esofágica/cirugía , Atresia Esofágica/complicaciones , Recién Nacido , Toracoscopía/métodos , Masculino , Femenino , Estudios Retrospectivos , Resultado del Tratamiento , Recién Nacido de Bajo Peso , Fuga Anastomótica/cirugíaRESUMEN
OBJECTIVE: Neurotrophin-like brain-derived neurotrophic factor (BDNF) and pro-inflammatory cytokines may modulate the pathophysiology of mood disorders. Although several studies show alterations in these biomarkers during the depressive, manic, and euthymic states of mood disorders, evidence is lacking for those in a mixed state. Therefore, this study aimed to investigate the relationship between the depressive mixed state (DMX) and peripheral neurobiological factors. METHODS: We enrolled 136 patients with major depressive episodes. Depressive symptoms were assessed using the Quick Inventory of Depressive Symptomatology Self-Report Japanese version (QIDS-SR-J). The severity of DMX was assessed using the self-administered 12-item questionnaire (DMX-12). Categorical screening as DMX-positive (n=54) was determined by a cutoff score of 13 or more in the specific eight symptoms from the DMX-12; the remaining were DMX-negative (n=82). Serum BDNF, tumor necrosis factor-α, highsensitivity C-reactive protein, and interleukin-6 levels were measured. RESULTS: When comparing biomarkers between the DMX-positive and DMX-negative groups, higher serum BDNF concentration in the DMX-positive group than in the DMX-negative group was the only significant finding (p=0.009). A positive correlation existed between the total score of the eight specific symptoms of DMX-12 and the BDNF concentration (r=0.190, p=0.027). After adjustment for confounders, logistic regression analysis revealed that BDNF (odds ratio [OR]=1.07, 95% confidence interval [CI]=1.00-1.14, p=0.045), bipolar diagnosis (OR=3.43, 95% CI=1.36-8.66, p=0.009), and total QIDS-SR-J score (OR=1.29, 95% CI=1.15-1.43, p<0.001) were significantly associated with DMX positivity. CONCLUSION: BDNF was positively associated with DMX severity, suggesting that higher BDNF concentrations may be involved in the pathophysiology of DMX.
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OBJECTIVE: The study clarified differences in understanding and satisfaction between face-to-face and online training on radiation emergency medical preparedness (REMP) training. METHODS: The training was held at Hirosaki University between 2018 and 2022, with 46 face-to-face participants and 25 online participants. RESULTS: Face-to-face training was significantly more understandable than online for the use of the Geiger counter (P < 0.05), but the educational effect of virtual reality (VR) was not significantly different from the actual practice. For the team exercise of taking care of the victims, online resulted in a significantly higher understanding (P < 0.05). CONCLUSIONS: Interactive exercises can be done online with equipment sent to learners, and VR is also as effective. The use of videos was more effective for first-timers to learn the practical process from a bird's-eye view, especially for team-based medical procedures.
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Aprendizaje , Realidad Virtual , HumanosRESUMEN
BACKGROUND & AIMS: Endocannabinoids (eCBs) are involved in various physiological functions such as appetite, metabolism, and inflammation. Although deterioration of these functions is often observed in patients with refractory cancer cachexia (RCC), the relationship between circulating eCBs and cancer cachexia remains unknown. This study aimed to evaluate the relationship between circulating levels of eCBs and clinical findings in patients with RCC. METHODS: Circulating N-arachidonoylethanolamine (anandamide, AEA) and 2-arachidonoylglycerol (2-AG) levels were measured in 39 patients with RCC (36% females, median age and IQR: 79 and 69-85), and 18 age- and sex-matched controls who received medical therapy for non-communicable diseases, using liquid chromatography with tandem mass spectrometry. In the RCC group, relationships between eCB levels and clinical findings-such as anorexia, awareness of pain, performance status, and survival period-were also examined. As anti-inflammatory drugs can influence the action and metabolism of eCBs, the following two analyses were conducted. In analysis 1, all participants were included, and in analysis 2, participants receiving any anti-inflammatory drugs were excluded. RESULTS: Serum AEA and 2-AG levels were more than twice as high in the RCC group than in those in the control group in both analyses. In analysis 1, only 8% of patients reported normal appetite assessed using the numerical rating scale (NRS), and serum AEA levels were negatively correlated with the NRS scores (R = -0.498, p = 0.001). Serum 2-AG levels were positively correlated with serum triglyceride levels (R = 0.419, p = 0.008). Both AEA and 2-AG levels were positively correlated with serum C-reactive protein (CRP) levels (AEA: R = 0.516, p < 0.001; 2-AG: R = 0.483, p = 0.002). Multiple linear regression analysis in the form of a stepwise procedure was performed; NRS scores and CRP levels showed a significant association with AEA levels (NRS: p = 0.001; CRP: p < 0.001), with an adjusted R2 value of 0.426. Similarly, triglyceride and CRP levels showed a significant association with the log of 2-AG levels (triglycerides: p < 0.001; CRP: p < 0.001), with an adjusted R2 value of 0.442. In analysis 2, serum AEA levels were negatively correlated with the NRS scores (R = -0.757, p < 0.001), whereas serum triglyceride levels were positively correlated with 2-AG levels (R = 0.623, p = 0.010). CONCLUSIONS: Circulating eCB levels were significantly higher in patients with RCC than those in controls. In patients with RCC, circulating AEA may play a role in anorexia, whereas 2-AG may play a role in serum triglyceride levels.
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Carcinoma de Células Renales , Neoplasias Renales , Femenino , Humanos , Masculino , Estudios Transversales , Endocannabinoides/metabolismo , Anorexia , Caquexia , TriglicéridosRESUMEN
CONTEXT: Individuals with chronic ankle instability (CAI) exhibit altered movement strategies during side-cutting tasks. However, no researchers have assessed how altered movement strategies affect cutting performance. OBJECTIVE: To investigate compensatory strategies in the side-hop test (SHT), with a focus on the entire lower extremity, among individuals with CAI. DESIGN: Cross-sectional study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 40 male soccer players comprising a CAI group (n = 20; age = 20.35 ± 1.15 years, height = 173.95 ± 6.07 cm, mass = 68.09 ± 6.73 kg) and a control group (n = 20; age = 20.45 ± 1.50 years, height = 172.39 ± 4.39 cm, mass = 67.16 ± 4.87 kg). INTERVENTION(S): Participants performed 3 successful SHT trials. MAIN OUTCOME MEASURE(S): We calculated SHT time, torque, and torque power in the ankle, knee, and hip joints during the SHT using motion-capture cameras and force plates. Confidence intervals for each group that did not overlap by >3 points consecutively in the time series data indicated a difference between groups. RESULTS: Compared with the control group, the CAI group showed (1) no delayed SHT time; (2) lower ankle-inversion torque (range = 0.11-0.13 N·m/kg) and higher hip-extension (range = 0.18-0.72 N·m/kg) and -abduction torque (0.26 N·m/kg); (3) less concentric power in ankle dorsiflexion-plantar flexion (0.18 W/kg) and inversion-eversion (0.40 W/kg), more concentric power in hip flexion-extension (0.73 W/kg), and more eccentric power in knee varus-valgus (0.27 W/kg). CONCLUSIONS: Individuals with CAI were likely to rely on hip-joint function to compensate for ankle instability and demonstrated no differences in SHT time compared with the control group. Therefore, the movement strategies of individuals with CAI could differ from those of individuals without CAI, even if SHT time is not different.
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Traumatismos del Tobillo , Inestabilidad de la Articulación , Humanos , Masculino , Adulto Joven , Adulto , Adolescente , Tobillo , Estudios Transversales , Traumatismos del Tobillo/diagnóstico , Articulación del Tobillo , Extremidad Inferior , Inestabilidad de la Articulación/diagnóstico , Fenómenos Biomecánicos , Enfermedad CrónicaRESUMEN
Cancer stem cells (CSCs) contribute to the drug resistance, recurrence, and metastasis of breast cancers. Recently, we demonstrated that HER2 overexpression increases mammosphere formation via the activation of aryl hydrocarbon receptor (AHR). In this study, the objective was to identify the mechanism underlying mammosphere maintenance mediated by HER2 signaling-activated AHR. We compared the chromatin structure of AHR-knockout (AHRKO) HER2-overexpressing MCF-7 (HER2-5) cells with that of wild-type HER2-5 cells; subsequently, we identified TP63, a stemness factor, as a potential target gene of AHR. ΔNp63 mRNA and protein levels were higher in HER2-5 cells than in HER2-5/AHRKO cells. Activation of HER2/HER3 signaling by heregulin treatment increased ΔNp63 mRNA levels, and its induction was decreased by AHR knockdown in HER2-5 cells. The results of the chromatin immunoprecipitation assay revealed an interaction between AHR and the intronic region of TP63, which encodes ΔNp63. A luciferase reporter gene assay with the intronic region of TP63 showed that AHR expression increased reporter activity. Collectively, our findings suggest that HER2-activated AHR upregulates ΔNp63 expression and that this signaling cascade is involved in CSC maintenance in HER2-expressing breast cancers.
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Neoplasias de la Mama , Receptores de Hidrocarburo de Aril , Humanos , Femenino , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Neurregulina-1/metabolismo , Regulación hacia Arriba , Neoplasias de la Mama/metabolismo , ARN Mensajero/genética , Luciferasas/metabolismo , Cromatina , Línea Celular TumoralRESUMEN
PM0042 protein from the Gram-negative bacterial pathogen Pasteurella multocida is homologous to the heme-degrading enzyme HutZ belonging to the pyridoxine-5-phosphate oxidase-like family. A characteristic feature of PM0042 is possession of a glycine-histidine (GH) repeat sequence at the C-terminal region. In this study, we examined the heme degradation ability of PM0042, with a particular focus on the role of the GH repeat sequence. PM0042 was expressed in Escherichia coli and successfully purified using a nickel (Ni2+)-affinity column without a histidine tag, suggesting that its GH motif facilitates binding to Ni2+. Reaction with ascorbic acid induced a significant decrease in the Soret band, suggesting the breakage of heme. While a Fe2+-ferrozine complex was not formed upon addition of ferrozine to the solution after the reaction, prior addition of metal ions to fill the metal binding site in the GH repeat sequence led to increased complex formation. In the presence of Fe2+, the heme degradation rate was accelerated â¼threefold, supporting the theory that Fe2+ binds the PM0042 protein (possibly at the GH repeat sequence) and enhances its heme degradation activity. In contrast to HutZ from Vibrio cholerae in which enzymatic activity is regulated by the protonation status of the heme proximal ligand, heme reduction is not the rate-determining step for PM0042. Rather, proton transfer to reduced oxyheme is affected, as established with the H2O/D2O isotope experiment. Based on the collective findings, the GH repeat sequence of PM0042 is proposed to function as a metal sensor that modulates iron uptake via the heme-degrading process in P. multocida.
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Histidina , Pasteurella multocida , Proteínas Bacterianas , Ferrozina , Glicina , HemoRESUMEN
Objective This study analyzed the clinical and laboratory parameters that might influence the clinical outcomes of patients with type 2 diabetes who develop diabetic ketoacidosis (DKA), which has not been well investigated. Methods We reviewed the clinical and laboratory data of 158 patients who were hospitalized due to DKA between January 2006 and June 2019 and compared the data of patients stratified by the type of diabetes. In addition, the patients with type 2 diabetes were subdivided according to age, and their clinical and laboratory findings were evaluated. Results Patients with type 2 diabetes had a longer symptom duration associated with DKA, higher body mass index (BMI), and higher C-peptide levels than those with type 1 diabetes (p<0.05). Among patients with type 2 diabetes, elderly patients (≥65 years old) had a longer duration of diabetes, higher frequency of DKA onset under diabetes treatment, higher effective osmolarity, lower BMI, and lower urinary C-peptide levels than nonelderly patients (<65 years old) (p<0.05). A correlation analysis showed that age was significantly negatively correlated with the index of insulin secretory capacity. Conclusion Patients with DKA and type 2 diabetes had a higher BMI and insulin secretion capacity than those with type 1 diabetes. However, elderly patients with type 2 diabetes, unlike younger patients, were characterized by a lean body, impaired insulin secretion, and more frequent DKA development while undergoing treatment for diabetes.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cetoacidosis Diabética , Anciano , Péptido C , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Cetoacidosis Diabética/complicaciones , Cetoacidosis Diabética/diagnóstico , Humanos , Secreción de Insulina , Estudios RetrospectivosRESUMEN
OBJECTIVE: The spread of COVID-19 has made it difficult to provide training in medical treatment in a radiation disaster. In this study, we will examine the effects and challenges of using a hybrid approach that combines online and face-to-face components. METHODS: A total of 5 face-to face and 25 online medical staff participated in the training program. This program was conducted by using multiple cameras for live coverage, while protective clothing and decontamination kits had been sent in advance to the participants so that they could experience face-to-face and online learning at the same time. RESULTS: Participants reported a high level of satisfaction and achievement with the style of delivery. They also experienced problems such as fatigue due to long hours, and dissatisfaction with the debriefing. CONCLUSIONS: In designing new online training, it is necessary to consider the quantity and content of the program, and to take participant fatigue into consideration.
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COVID-19 , Desastres , Educación a Distancia , Humanos , COVID-19/epidemiología , Pandemias/prevención & controlRESUMEN
Uphill training is applied to induce specific overload on the musculoskeletal system to improve sprinting mechanics. This study aimed to identify unique kinematic features of uphill sprinting at different slopes and to suggest practical implications based on comparisons we early stance phase. At take-off, steeper slopes induced significantly more extended joint angles and higher ROMs during the late stance phase. Compared with moderate slopes, more anti-phase coordination patterns were detected at steeper slopes. Thus, uphill sprinting at steeper slopes shares essential kinematic features with the early acceleration phase of level sprinting. Moderate inclinations induce biomechanical adaptations similar to those in the late acceleration phase of level sprinting. Hence, the specific transfer of uphill sprinting to acceleration depends on the slope inclinations.
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Extremidad Inferior/fisiología , Acondicionamiento Físico Humano/métodos , Carrera/fisiología , Aceleración , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Ambiente , Articulación de la Cadera/fisiología , Humanos , Articulación de la Rodilla/fisiología , Masculino , Rango del Movimiento Articular , Torso/fisiología , Adulto JovenRESUMEN
In DNA aptamer selection, existing methods do not discriminate aptamer sequences based on their binding affinity and function and the reproducibility of the selection is often poor, even for the selection of well-known aptamers like those that bind the commonly used model protein thrombin. In the present study, a novel single-round selection method (SR-CE selection) was developed by combining capillary electrophoresis (CE) with next generation sequencing. Using SR-CE selection, a successful semi-quantitative and semi-comprehensive aptamer selection for thrombin was demonstrated with high reproducibility for the first time. Selection rules based on dissociation equilibria and kinetics were devised to obtain families of analogous sequences. Selected sequences of the same family were shown to bind thrombin with high affinity. Furthermore, data acquired from SR-CE selection was mined by creating sub-libraries that were categorized by the functionality of the aptamers (e. g., pre-organized aptamers versus structure-induced aptamers). Using this approach, a novel fluorescent molecular recognition sensor for thrombin with nanomolar detection limits was discovered. Thus, in this proof-of-concept report, we have demonstrated the potential of a "DNA Aptaomics" approach to systematically design functional aptamers as well as to obtain high affinity aptamers.
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Aptámeros de Nucleótidos , Electroforesis Capilar , Secuenciación de Nucleótidos de Alto Rendimiento , Reproducibilidad de los Resultados , TrombinaRESUMEN
AIMS/INTRODUCTION: We aimed to examine the association between diabetes-related parameters and hippocampal and parahippocampal gyrus atrophy (HPGA) in patients with type 2 diabetes mellitus to elucidate the risk factors for HPGA, which is often accompanied by Alzheimer's disease. MATERIALS AND METHODS: A total of 137 patients aged ≥50 years with type 2 diabetes mellitus (mean age 67.8 ± 9.8 years) underwent brain magnetic resonance imaging scans and comprehensive health examinations. We measured the volume of interest - a portion of the inner temporal lobe that includes the hippocampus, amygdala and entorhinal cortex (frontal part of the parahippocampal gyrus) - using the voxel-based specific regional analysis system for Alzheimer's disease in each patient. The diabetes-related parameters included glycated hemoglobin, fasting plasma glucose, C-peptide (CPR) index (serum CPR / fasting plasma glucose × 100) and duration of diabetes. RESULTS: The mean glycated hemoglobin was 9.3 ± 2.2%, the median CPR index was 1.29 (interquartile range 0.85-1.74) and the median duration of diabetes was 10 years (interquartile range 3-20 years). The severity score of volume of interest atrophy was >1.0 in 36 patients. Using multivariate logistic regression analysis, we found that age (odds ratio 1.09, 95% confidence interval 1.02-1.15) and CPR index (odds ratio 0.451, 95% confidence interval 0.216-0.940) were significantly associated with HPGA. CONCLUSIONS: Lower insulin secretion was significantly associated with HPGA in patients with type 2 diabetes mellitus. The results of this study support the hypothesis that insulin-signaling abnormalities are involved in the pathophysiology of Alzheimer's disease.
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Diabetes Mellitus Tipo 2/diagnóstico por imagen , Secreción de Insulina , Giro Parahipocampal/diagnóstico por imagen , Anciano , Estudios Transversales , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
HutZ from Vibrio cholerae is a dimeric enzyme that catalyzes degradation of heme. The highly conserved Arg92 residue in the HutZ family is proposed to interact with an iron-bound water molecule in the distal heme pocket. To clarify the specific role of Arg92 in the heme degradation reaction, the residue was substituted with alanine, leucine, histidine or lysine to modulate electrostatic interactions with iron-bound ligand. All four Arg92 mutants reacted with hydrogen peroxide to form verdoheme, a prominent intermediate in the heme degradation process. However, when ascorbic acid was used as an electron source, iron was not released even at pH 6.0 despite a decrease in the Soret band, indicating that non-enzymatic heme degradation occurred. Comparison of the rates of heme reduction, ligand binding and verdoheme formation suggested that proton transfer to the reduced oxyferrous heme, a potential rate-limiting step of heme degradation in HutZ, is hampered by mutation. In our previous study, we found that the increase in the distance between heme and Trp109 from 16 to 18â¯Å upon lowering the pH from 8.0 to 6.0 leads to activation of ascorbic acid-assisted heme degradation by HutZ. The distance in Arg92 mutants was >19â¯Åâ¯at pH 6.0, suggesting that subunit-subunit interactions at this pH are not suitable for heme degradation, similar to Asp132 and His63 mutants. These results suggest that interactions of Arg92 with heme-bound ligand induce alterations in the distance between subunits, which plays a key role in controlling the heme degradation activity of HutZ.
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Arginina/química , Proteínas Bacterianas/química , Hemo/química , Oxigenasas de Función Mixta/química , Vibrio cholerae/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Hemo/metabolismo , Ligandos , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Mutación , Oxidación-Reducción , Unión Proteica , Agua/químicaRESUMEN
HutZ, a dimeric protein, from Vibrio cholerae is a protein that catalyzes the oxygen-dependent degradation of heme. Interestingly, the ascorbic acid-supported heme-degradation activity of HutZ depends on pH: less than 10% of heme is degraded by HutZ at pH 8.0, but nearly 90% of heme is degraded at pH 6.0. We examined here pH-dependent conformational changes in HutZ using fluorescence spectroscopy. Trp109 is estimated to be located approximately 21 Å from heme and is present in a different subunit containing a heme axial ligand. Thus, we postulated that the distance between heme and Trp109 reflects subunit-subunit orientational changes. On the basis of resonance energy transfer from Trp109 to heme, we estimated the distance between heme and Trp109 to be approximately 17 Å at pH 8.0, while the distance increased by less than 2 Å at pH 6.0. We presumed that such changes led to a decrease in electron donation from the proximal histidine, resulting in enhancement of the heme-degradation activity. To confirm this scenario, we mutated Ala31, located at the dimer interface, to valine to alter the distance through the subunit-subunit interaction. The distance between heme and Trp109 for the A31V mutant was elongated to 24-27 Å. Although resonance Raman spectra and reduction rate of heme suggested that this mutation resulted in diminished electron donation from the heme axial ligand, ascorbic acid-supported heme-degradation activity was not observed. Based on our findings, it can be proposed that the relative positioning of two protomers is important in determining the heme degradation rate by HutZ.
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Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Hemo/química , Hemo/metabolismo , Vibrio cholerae/química , Proteínas Bacterianas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Modelos Moleculares , Estructura Molecular , Oxidación-Reducción , Espectrometría de Fluorescencia , Vibrio cholerae/metabolismoRESUMEN
Diazoxide is recognized as an effective medical treatment for insulinoma. However, due to its adverse effects, such as fluid retention, it is sometimes difficult to employ diazoxide at an effective dose in clinical practice. This study aimed to clarify the clinical factors, which may affect efficacy and safety of the diazoxide treatment. We retrospectively evaluated the medical records of 20 patients with insulinoma including 4 malignant cases. The patients were divided into two groups according to the presence or absence of favorable outcomes or adverse effects, and the clinical features of both groups were compared. Diazoxide was effective and ineffective in each 9 patients, respectively. In other 2 cases, the efficacy could not be determined. In the effective group, all patients had benign insulinoma. Additionally, the tumor size determined by imaging test was tended to smaller than the ineffective group but not statistically significant when malignant cases were excluded (p = 0.065). Fluid retention was observed more frequently in females than in males (p = 0.025). Five patients displayed unacceptable thrombocytopenia within a few weeks after the administration of diazoxide. In these patients, the diazoxide dose was significantly higher than that in the other patients [400 mg/day (250-500 mg/day) vs. 225 mg/day (50-425 mg/day), p = 0.027]. These findings may be informative in determining the indication and dose of diazoxide against insulinoma. In addition, a careful evaluation of platelet count would be required for a few weeks after the initiation of diazoxide treatment.
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Antineoplásicos/uso terapéutico , Diazóxido/uso terapéutico , Insulinoma/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: The swelling properties and the drug-release sustainability of pre-gelatinized starches (ð¼-starch) tablets depend on the polymer characteristics. OBJECTBS: In order to clarify the drug release form, the natural polymers (NPs) were investigated. The relationship between drug release and swelling of natural polymers (NPs), the swelling processes of various starch polymers, were investigated using a drug-release test (DRT) and X-ray computed tomography (XCT). NPs consisting of various starches such as glutinous rice starch (GRS), corn starch (CS), and tapioca starch (TS) were used as additives for sustained drug-release tablets. Tablets consisted of 5% theophylline, 94% ð¼-starch, and 1% magnesium stearate and were compressed at 6 kN. DRTs were measured in distilled water at 37 °C, and the drug concentrations were measured using UV (271 nm). Swelling ratio (R) profiles of the tablets during DRTs were evaluated based on XCT images. RESULTS: The order of the drug-release rate constant of the tablets was TS < GRS < CS. XCT images of the tablets were measured during the DRTs, and CS, GRS, and TS tablets swelled and showed increased gel-layers, and then finally disintegrated at 6, 9, and 11 h, respectively. CONCLUSION: The relationship between R profile and the % drug release of the tablets differed depending on the kind of NP used.
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Preparaciones de Acción Retardada/química , Comprimidos/química , Portadores de Fármacos , Liberación de Fármacos , Humanos , Almidón , Relación Estructura-Actividad , Tomografía Computarizada por Rayos XRESUMEN
A single-pixel camera can be represented using complex-amplitude. The complex-amplitude representation of input signals and output signals enables us to perform complex-amplitude imaging of an object, particularly profilometry with reflectance measurements or quantitative phase imaging with transmittance measurements. The complex-amplitude representation of optical coding masks and the coherent addition that is performed by interference can directly represent Hadamard patterns having positive and negative values. Furthermore, the residual area of the mask can be used for a reference beam with phase shifting. Such a complex-amplitude imaging system with a single-beam line structure is highly stabile against external disturbances.