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1.
Nature ; 573(7773): 238-242, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31511686

RESUMEN

The metastable first excited state of thorium-229, 229mTh, is just a few electronvolts above the nuclear ground state1-4 and is accessible by vacuum ultraviolet lasers. The ability to manipulate the 229Th nuclear states with the precision of atomic laser spectroscopy5 opens up several prospects6, from studies of fundamental interactions in physics7,8 to applications such as a compact and robust nuclear clock5,9,10. However, direct optical excitation of the isomer and its radiative decay to the ground state have not yet been observed, and several key nuclear structure parameters-such as the exact energies and half-lives of the low-lying nuclear levels of 229Th-remain unknown11. Here we present active optical pumping into 229mTh, achieved using narrow-band 29-kiloelectronvolt synchrotron radiation to resonantly excite the second excited state of 229Th, which then decays predominantly into the isomer. We determine the resonance energy with an accuracy of 0.07 electronvolts, measure a half-life of 82.2 picoseconds and an excitation linewidth of 1.70 nanoelectronvolts, and extract the branching ratio of the second excited state into the ground and isomeric state. These measurements allow us to constrain the 229mTh isomer energy by combining them with γ-spectroscopy data collected over the past 40 years.

2.
Proc Natl Acad Sci U S A ; 119(42): e2204405119, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36215500

RESUMEN

Ecosystems are complex systems of various physical, biological, and chemical processes. Since ecosystem dynamics are composed of a mixture of different levels of stochasticity and nonlinearity, handling these data is a challenge for existing methods of time series-based causal inferences. Here, we show that, by harnessing contemporary machine learning approaches, the concept of Granger causality can be effectively extended to the analysis of complex ecosystem time series and bridge the gap between dynamical and statistical approaches. The central idea is to use an ensemble of fast and highly predictive artificial neural networks to select a minimal set of variables that maximizes the prediction of a given variable. It enables decomposition of the relationship among variables through quantifying the contribution of an individual variable to the overall predictive performance. We show how our approach, EcohNet, can improve interaction network inference for a mesocosm experiment and simulated ecosystems. The application of the method to a long-term lake monitoring dataset yielded interpretable results on the drivers causing cyanobacteria blooms, which is a serious threat to ecological integrity and ecosystem services. Since performance of EcohNet is enhanced by its predictive capabilities, it also provides an optimized forecasting of overall components in ecosystems. EcohNet could be used to analyze complex and hybrid multivariate time series in many scientific areas not limited to ecosystems.


Asunto(s)
Ecosistema , Redes Neurales de la Computación , Causalidad , Lagos , Aprendizaje Automático
3.
Eur Spine J ; 33(1): 77-83, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37889328

RESUMEN

PURPOSE: This cross-sectional study serves two main purposes. Firstly, it aims to validate the preoperative Japanese Core Outcome Measures Index for the Neck (COMI-Neck) in patients with cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL). Secondly, it seeks to elucidate differences in preoperative quality of life (QOL) between these two cervical pathologies using patient-reported outcome measures (PROMs). METHODS: A total of 103 preoperative patients (86 with CSM and 17 with OPLL) scheduled for cervical spine surgery were included in the study. Validated PROMs, including the Japanese COMI-Neck, Neck Disability Index (NDI), EuroQol-5 Dimension-3 level (EQ-5D-3L), and SF-12v2, were used to assess QOL. Baseline demographic and clinical data were collected, and statistical analyses were performed to compare the PROMs between CSM and OPLL groups. RESULTS: The Japanese COMI-Neck demonstrated good construct validity, with positive correlations with NDI and negative correlations with EQ-5D-3L and SF-12v2. Comparison of preoperative PROMs between CSM and OPLL groups revealed differences in age, body mass index, and EQ-5D-3L scores. The CSM group had higher NDI scores for concentration and lower EQ-5D-3L scores for self-care compared to the OPLL group. CONCLUSIONS: This study validated the preoperative Japanese COMI-Neck in CSM and OPLL patients and identified specific QOL issues associated with each condition. The findings highlight the importance of considering disease-specific QOL and tailoring treatment plans accordingly. Further research should include postoperative assessments and a more diverse population to enhance generalizability.


Asunto(s)
Osificación del Ligamento Longitudinal Posterior , Enfermedades de la Médula Espinal , Espondilosis , Humanos , Vértebras Cervicales/cirugía , Estudios Transversales , Ligamentos Longitudinales , Osificación del Ligamento Longitudinal Posterior/cirugía , Osificación del Ligamento Longitudinal Posterior/complicaciones , Osteogénesis , Evaluación de Resultado en la Atención de Salud , Medición de Resultados Informados por el Paciente , Calidad de Vida , Enfermedades de la Médula Espinal/cirugía , Enfermedades de la Médula Espinal/complicaciones , Espondilosis/cirugía , Espondilosis/complicaciones , Resultado del Tratamiento
4.
Eur Spine J ; 33(6): 2198-2205, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679673

RESUMEN

PURPOSE: The primary objective was to validate the construct validity of the Japanese Core Outcome Measures Index (COMI) in preoperative patients aged 60 years or older undergoing lumbar spine surgery for lumbar spinal stenosis (LSS) and lumbar disk herniation (LDH). Additionally, as a secondary aim, we explored the impact of these diseases on quality of life (QOL). METHODS: The analysis included 199 preoperative patients aged 60 and above who were scheduled for lumbar spine surgery. To assess QOL, Japanese versions of the COMI, Oswestry Disability Index (ODI), EuroQol-5 Dimension-3 Level (EQ-5D-3L), and SF-12v2 were employed. The study assessed the validity of the COMI and compared demographic and clinical characteristics between the LSS (147 cases) and LDH (52 cases) groups. It used multivariate covariance analysis (MANCOVA) to examine the impact of diseases (LSS and LDH) on each patient-reported outcome measure while considering covariates. RESULTS: Compared to the LSS group, the LDH group showed more difficulty with the COMI summary score (LSS/LDH [mean]: 6.9/8.1, p < 0.001), ODI score (46.8/57.4, p < 0.001), and EQ-5D utility (0.53/0.43, p < 0.001). The LDH group also reported more difficulties in the COMI-function, COMI-symptom-specific well-being, COMI-disability, ODI-personal care, ODI-social life, and SF-12v2-bodily pain subscales. MANCOVA demonstrated that these results were not influenced by covariates such as gender and medical history. CONCLUSIONS: This study highlights the distinct impact of LSS and LDH on preoperative QOL in older patients undergoing lumbar spinal surgery. Tailored interventions are essential to address the specific challenges posed by these conditions and improve patient-centered outcomes and postoperative recovery.


Asunto(s)
Desplazamiento del Disco Intervertebral , Vértebras Lumbares , Medición de Resultados Informados por el Paciente , Calidad de Vida , Estenosis Espinal , Humanos , Estenosis Espinal/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/complicaciones , Masculino , Femenino , Anciano , Vértebras Lumbares/cirugía , Persona de Mediana Edad , Japón , Anciano de 80 o más Años , Evaluación de la Discapacidad , Pueblos del Este de Asia
5.
Environ Res ; 219: 115130, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36563976

RESUMEN

Coastal seagrass meadows are essential in blue carbon and aquatic ecosystem services. However, this ecosystem has suffered severe eutrophication and destruction due to the expansion of aquaculture. Therefore, methods for the flourishing of seagrass are still being explored. Here, data from 49 public coastal surveys on the distribution of seagrass and seaweed around the onshore aquaculture facilities are revalidated, and an exceptional area where the seagrass Zostera marina thrives was found near the shore downstream of the onshore aquaculture facility. To evaluate the characteristics of the sediment for growing seagrass, physicochemical properties and bacterial ecological evaluations of the sediment were conducted. Evaluation of chemical properties in seagrass sediments confirmed a significant increase in total carbon and a decrease in zinc content. Association analysis and linear discriminant analysis refined bacterial candidates specified in seagrass overgrown- and nonovergrown-sediment. Energy landscape analysis indicated that the symbiotic bacterial groups of seagrass sediment were strongly affected by the distance close to the seagrass-growing aquaculture facility despite their bacterial population appearing to fluctuate seasonally. The bacterial population there showed an apparent decrease in the pathogen candidates belonging to the order Flavobacteriales. Moreover, structure equation modeling and a linear non-Gaussian acyclic model based on the machine learning data estimated an optimal sediment symbiotic bacterial group candidate for seagrass growth as follows: the Lachnospiraceae and Ruminococcaceae families as gut-inhabitant bacteria, Rhodobacteraceae as photosynthetic bacteria, and Desulfobulbaceae as cable bacteria modulating oxygen or nitrate reduction and oxidation of sulfide. These observations confer a novel perspective on the sediment symbiotic bacterial structures critical for blue carbon and low-pathogenic marine ecosystems in aquaculture.


Asunto(s)
Ecosistema , Zosteraceae , Humanos , Sedimentos Geológicos/análisis , Acuicultura , Carbono/análisis , Bacterias
6.
J Clin Biochem Nutr ; 73(2): 124-130, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37700845

RESUMEN

The impact of repeated administration of cinntamtannin A2 (A2, 25 µg/kg) on skeletal muscle disuse atrophy model mice induced by hindlimb suspension for 14 days was examined. In soleus, weight loss and a reduction in the average myofibre size with shifting to the smaller side of the peak were observed in the suspension-vehicle group, but A2 reduced these changes. Average myofibre size significantly increased in ground-A2 compared to ground-vehicle. A marked increase in the dephosphorylation of forkhead box O (FoxO) 3a by the suspension was reduced by A2. The phosphorylation of protein kinase B (Akt) and eukaryotic translation initiation factor 4E-binding protein (4EBP)-1 were significantly increased by the treatment of A2. In addition, a single dose of A2 increased dramatically in the 24-h excretion of catecholamines in urine. These results suggest that A2 administration results in sympathetic nerve activation and promotes hypertrophy while inhibiting the progress of disuse muscle atrophy.

7.
J Phys Ther Sci ; 34(11): 737-740, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36337221

RESUMEN

[Purpose] To evaluate the inter-examiner reliability of our novel parameter, the lumbar paraspinal muscle atrophy index, in identifying the lumbar paravertebral muscle atrophy. [Participants and Methods] The study group consisted of 225 adults, with a mean age of 64.7 (range, 21-89) years, who underwent posterior lumbar spinal surgery for degenerative spinal disease at our hospital between July 2013 and June 2017. Preoperative axial T2-weighted magnetic resonance images were used to evaluate the lumbar paraspinal muscle atrophy index and observe the presence or absence of severe lumbar paraspinal muscle atrophy. The lumbar paraspinal muscle atrophy index was calculated at each intervertebral level, from L1-2 through L4-5, once by two examiners, and the Cohen's kappa statistic was used to calculate the inter-examiner agreement of the classification of the presence or absence of atrophy at each level. [Results] The agreement was high (kappa, 0.79-0.88) for the lumbar paraspinal muscle atrophy index at all levels, except at the L3-4 level (kappa, 0.49). The lower kappa statistic at L3-4 likely reflects the unique morphological characteristics at this level. [Conclusion] The lumbar paraspinal muscle atrophy index is a new, simple, easy-to-use, and sufficiently reliable parameter to identify lumbar paraspinal atrophy.

8.
Surg Today ; 51(7): 1212-1219, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33420821

RESUMEN

PURPOSE: Laparoscopic hepatojejunostomy (HJ) with continuous sutures is commonly performed in laparoscopic pancreaticoduodenectomy (LPD). This study aimed to investigate the long-term surgical outcomes of HJ in LPD. METHODS: We retrospectively evaluated 103 consecutive patients who underwent pancreaticoduodenectomy via laparoscopic HJ with continuous suturing using multifilament (n = 48) or monofilament-absorbable sutures (n = 47). RESULTS: During follow-up, anastomotic stricture of HJ was identified in 8 (7.8%) patients via balloon enteroscopy-assisted cholangiography. The median time from surgery to confirmation of stricture formation was 7.6 months (range 3.6-19.4). The incidence of HJ stricture was significantly higher in patients with a thin bile duct (diameter < 6.0 mm) than in those with a thick bile duct (diameter ≥ 6.0 mm) [7/27 (25.9%) vs. 1/76 (1.3%), respectively, p < 0.01]. Similarly, it was significantly higher in the monofilament group than in the multifilament group [7/54 (13.0%) vs. 1/49 (2.0%), respectively, p = 0.04]. In the monofilament suture group, 37.5% of patients with thin bile ducts developed stricture after HJ. A multivariate analysis revealed that a thin bile duct was an independent risk factor for HJ stricture (hazard ratio: 25.3, p < 0.01). CONCLUSIONS: Stricture after laparoscopic HJ using continuous sutures frequently occurs in patients with thin bile ducts, particularly when monofilament-absorbable suture is used.


Asunto(s)
Anastomosis Quirúrgica/efectos adversos , Conductos Biliares/patología , Yeyunostomía/efectos adversos , Laparoscopía/efectos adversos , Pancreaticoduodenectomía/efectos adversos , Técnicas de Sutura/efectos adversos , Suturas/efectos adversos , Conductos Biliares/diagnóstico por imagen , Conductos Biliares/cirugía , Constricción Patológica/etiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Surg Today ; 51(11): 1813-1818, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33907898

RESUMEN

PURPOSE: Clinically relevant postoperative pancreatic fistulas (CR-POPF) occurring after distal pancreatectomy often cause intra-abdominal infections. We monitored the presence of bacterial contamination in the ascitic fluid after distal pancreatectomy to clarify the bacterial origin of intra-abdominal infections associated with CR-POPF. METHODS: In 176 patients who underwent distal pancreatectomy, ascitic fluid bacterial cultures were performed on postoperative days (POD) 1-4 and when the drainage fluid became turbid. The association between postoperative ascitic bacterial contamination and CR-POPF incidence was investigated. RESULTS: CR-POPF occurred in 18 cases (10.2%). Among the patients with CR-POPF, bacterial contamination was detected in 0% on POD 1, in 38.9% on POD 4, and in 72.2% on the day (median, day 9.5) when the drainage fluid became turbid. A univariate analysis revealed a significant difference in ascitic bacterial contamination on POD 4 (p < 0.001) and amylase level on POD 3-4 (p < 0.001). A multivariate analysis revealed the amylase level and ascitic bacterial contamination on POD 4 to be independent risk factors. CONCLUSIONS: In the CR-POPF group, ascitic bacterial contamination was not observed in the early postoperative stage, but the bacterial contamination rate increased after pancreatic juice leakage occurred. Therefore, CR-POPF-related infections in distal pancreatectomy may be caused by a retrograde infection of pancreatic juice.


Asunto(s)
Líquido Ascítico/microbiología , Infecciones Bacterianas/microbiología , Pancreatectomía/efectos adversos , Pancreatectomía/métodos , Fístula Pancreática/microbiología , Complicaciones Posoperatorias/microbiología , Infección de la Herida Quirúrgica/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Amilasas/metabolismo , Líquido Ascítico/enzimología , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/etiología , Corynebacterium/aislamiento & purificación , Corynebacterium/patogenicidad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Fístula Pancreática/epidemiología , Fístula Pancreática/etiología , Jugo Pancreático/microbiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Pseudomonas/aislamiento & purificación , Pseudomonas/patogenicidad , Factores de Riesgo , Staphylococcus/aislamiento & purificación , Staphylococcus/patogenicidad , Streptococcus/aislamiento & purificación , Streptococcus/patogenicidad , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Factores de Tiempo
10.
J Clin Biochem Nutr ; 68(3): 228-234, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34025025

RESUMEN

We previously found that a single dose of theaflavins induced skeletal muscle metabolic changes. In this study, we examined the effect of theaflavins on disuse muscle atrophy model mice by hindlimb suspension. Mice were assigned to 4 groups; ground-vehicle, ground-theaflavins, suspension-vehicle, and suspension-theaflavins, dosed with theaflavins (250 mg/kg/day) for 2 weeks. The peak of myotube size of cross sectional area was significantly moved to the smaller side in the suspension-vehicle group compared with the ground-vehicle group, and these shifts were significantly reduced by the treatment with theaflavins in both soleus and extensor digitorum longus. The level of phosphorylated eukaryotic translation initiation factor 4E-binding protein (4EBP)-1, located downstream of the Akt/mTOR pathway, was significantly different between suspension-vehicle and suspension-theaflavins in soleus. The ratio of forkhead box O (FoxO) 3a to phosphorylated FoxO3a significantly increased in soleus or tended to rise in extensor digitorum longus of suspension-vehicle group compared with ground-vehicle. In contrast, these changes were not observed in suspension-theaflavins group. These results suggested that theaflavins inhibited the progress of disuse muscle atrophy through modulation of protein metabolism.

11.
J Phys Ther Sci ; 33(8): 591-595, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34393369

RESUMEN

[Purpose] To clarify the inter-rater reliability of the evaluation criteria for paraspinal muscle fat infiltration on magnetic resonance images between two examiners with different professional roles in interdisciplinary physical therapy teams. [Participants and Methods] In this retrospective study, we reviewed the clinical data of 225 patients with degenerative lumbar diseases who underwent posterior lumbar surgery at our hospital. A physical therapist and a spinal surgeon visually quantified fat infiltration of the multifidus muscles at the level of L4/5 on the preoperative magnetic resonance images of the patients using Kjaer's criteria (Grade 0: 0-10%, Grade 1: 10-50%, and Grade 2: >50%). We used the kappa coefficient to assess inter-rater reliability. [Results] The participants included 142 males and 83 females (mean age, 64.7 years; range, 21-89 years). The number of patients with grades 0/1/2 were 50/160/15, respectively, for examiner 1; and 59/155/11, respectively, for examiner 2. The kappa coefficient was 0.69, indicating a substantial agreement. [Conclusion] Our study, which is the first to assess the inter-rater reliability of Kjaer's criteria between examiners with different medical occupations, revealed that these criteria could be a reliable tool for evaluating fat infiltration in the multifidus muscles and sharing information between interdisciplinary physical therapy teams.

12.
Surg Endosc ; 34(7): 2904-2910, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32377838

RESUMEN

BACKGROUND: Based on the spatial relationship of an aberrant right hepatic duct (ARHD) with the cystic duct and gallbladder neck, we propose a practical classification to evaluate the specific form predisposing to injury in laparoscopic cholecystectomy (LC). METHODS: We retrospectively investigated the preoperative images (mostly magnetic resonance cholangiopancreatography) and clinical outcomes of 721 consecutive patients who underwent LC at our institute from 2015 to 2018. We defined the high-risk ARHD as follows: Type A: communicating with the cystic duct and Type B: running along the gallbladder neck or adjacent to the infundibulum (the minimal distance from the ARHD < 5 mm), regardless of the confluence pattern in the biliary tree. Other ARHDs were considered to be of low risk. RESULTS: A high-risk ARHD was identified in 16 cases (2.2%): four (0.6%) with Type A anatomy and 12 (1.7%) with Type B. The remaining ARHD cases (n = 34, 4.7%) were categorized as low risk. There were no significant differences in the operative outcomes (operative time, blood loss, hospital stay) between the high- and low- risk groups. Subtotal cholecystectomy was applied in four cases (25%) in the high-risk group, a significantly higher percentage than the low-risk group (n = 1, 2.9%). In all patients with high-risk ARHD, LC was completed safely without bile duct injury or conversion to laparotomy. CONCLUSIONS: Our simple classification of high-risk ARHD can highlight the variants located close to the dissecting site to achieve a critical view of safety and may contribute to avoiding inadvertent damage of an ARHD in LC.


Asunto(s)
Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/métodos , Conducto Hepático Común/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Conductos Biliares/lesiones , Pancreatocolangiografía por Resonancia Magnética , Conducto Cístico/anatomía & histología , Conducto Cístico/diagnóstico por imagen , Femenino , Vesícula Biliar/anatomía & histología , Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Enfermedades de la Vesícula Biliar/cirugía , Conducto Hepático Común/diagnóstico por imagen , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias/etiología , Cuidados Preoperatorios , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
13.
Surg Today ; 50(12): 1664-1671, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32577883

RESUMEN

PURPOSE: The left renal vein is technically difficult to expose during laparoscopic distal pancreatectomy for pancreatic ductal adenocarcinoma despite being an important landmark for posterior dissection. We hereby propose a novel technique to safely expose the left renal vein while avoiding the associated anatomical pitfalls. METHODS: The anatomy of the left renal artery and vein was analyzed using multidetector computed tomography. We initially exposed the left renal vein on the left posterior side of the superior mesenteric artery followed by exposure toward the left kidney. We retrospectively examined the perioperative results of this technique in 33 patients who underwent laparoscopic distal pancreatectomy. RESULTS: 15.7% of the patients had an accessory left renal artery coursing cranial to the vein. In 43.1%, the left renal arterial branch ventrally traversed the vein at the renal hilum, thereby posing a risk for arterial injury. The location of the left renal vein varies cranial (17.6%) or caudal (82.4%) to the pancreas. The left renal vein was exposed without any vascular injury using this technique. The median operative time was 259 min, blood loss was 18 mL, and R0 resection rate was 97.0%. CONCLUSIONS: The initial exposure of the left renal vein should, therefore, be on the left posterior side of the superior mesenteric artery.


Asunto(s)
Variación Anatómica , Carcinoma Ductal Pancreático/cirugía , Laparoscopía/métodos , Páncreas/irrigación sanguínea , Páncreas/cirugía , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Venas Renales/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/diagnóstico por imagen , Femenino , Humanos , Masculino , Arteria Mesentérica Superior/anatomía & histología , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Neoplasias Pancreáticas/diagnóstico por imagen , Arteria Renal/anatomía & histología , Arteria Renal/diagnóstico por imagen , Venas Renales/diagnóstico por imagen , Estudios Retrospectivos , Seguridad
14.
Angew Chem Int Ed Engl ; 59(22): 8464-8470, 2020 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-32129542

RESUMEN

Shimalactones A and B are neuritogenic polyketides possessing characteristic oxabicyclo[2.2.1]heptane and bicyclo[4.2.0]octadiene ring systems that are produced by the marine fungus Emericella variecolor GF10. We identified a candidate biosynthetic gene cluster and conducted heterologous expression analysis. Expression of ShmA polyketide synthase in Aspergillus oryzae resulted in the production of preshimalactone. Aspergillus oryzae and Saccharomyces cerevisiae transformants expressing ShmA and ShmB produced shimalactones A and B, thus suggesting that the double bicyclo-ring formation reactions proceed non-enzymatically from preshimalactone epoxide. DFT calculations strongly support the idea that oxabicyclo-ring formation and 8π-6π electrocyclization proceed spontaneously after opening of the preshimalactone epoxide ring through protonation. We confirmed the formation of preshimalactone epoxide in vitro, followed by its non-enzymatic conversion to shimalactones in the dark.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/química , Lactonas/química , Lactonas/metabolismo , Aspergillus/genética , Aspergillus/metabolismo , Biotransformación , Ciclización , Familia de Multigenes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
15.
Nature ; 498(7452): 104-8, 2013 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-23719373

RESUMEN

Human language, as well as birdsong, relies on the ability to arrange vocal elements in new sequences. However, little is known about the ontogenetic origin of this capacity. Here we track the development of vocal combinatorial capacity in three species of vocal learners, combining an experimental approach in zebra finches (Taeniopygia guttata) with an analysis of natural development of vocal transitions in Bengalese finches (Lonchura striata domestica) and pre-lingual human infants. We find a common, stepwise pattern of acquiring vocal transitions across species. In our first study, juvenile zebra finches were trained to perform one song and then the training target was altered, prompting the birds to swap syllable order, or insert a new syllable into a string. All birds solved these permutation tasks in a series of steps, gradually approximating the target sequence by acquiring new pairwise syllable transitions, sometimes too slowly to accomplish the task fully. Similarly, in the more complex songs of Bengalese finches, branching points and bidirectional transitions in song syntax were acquired in a stepwise fashion, starting from a more restrictive set of vocal transitions. The babbling of pre-lingual human infants showed a similar pattern: instead of a single developmental shift from reduplicated to variegated babbling (that is, from repetitive to diverse sequences), we observed multiple shifts, where each new syllable type slowly acquired a diversity of pairwise transitions, asynchronously over development. Collectively, these results point to a common generative process that is conserved across species, suggesting that the long-noted gap between perceptual versus motor combinatorial capabilities in human infants may arise partly from the challenges in constructing new pairwise vocal transitions.


Asunto(s)
Lenguaje Infantil , Pinzones/fisiología , Vocalización Animal/fisiología , Animales , Evolución Biológica , Humanos , Lactante , Masculino , Modelos Biológicos , Fonética , Habla/fisiología , Factores de Tiempo
16.
J Clin Biochem Nutr ; 65(1): 29-33, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31379411

RESUMEN

Cinnamtannin A2, an (-)-epicatechin tetramer, was reported to have potent physiological activity. Cinnamtannin A2 is rarely absorbed from the gastrointestinal tract into the blood and the mechanisms of its beneficial activities are unknown. Cinnamtannin A2 reported to increase sympathetic nervous activity, which was induced by various stressors. In present study, we examined the stress response in the mouse paraventricular nucleus following a single oral dose of cinnamtannin A2 by monitoring mRNA expression of corticotropin-releasing hormone (CRH) and c-fos using in situ hybridization. Corticotropin-releasing hormone mRNA showed a tendency to increase at 15 min and significantly increased at 60 min following a single oral administration of 100 µg/kg cinnamtannin A2. After a single dose of 10 µg/kg cinnamtannin A2, there was significant upregulation of CRH mRNA at 60 min. These results suggested that cinnamtannin A2 was recognized as a stressor in central nervous system and this may lead to its beneficial effects on circulation and metabolism.

17.
Ecology ; 99(9): 2025-2036, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29884987

RESUMEN

Nutrient supply is a key bottom-up control of phytoplankton primary production in lake ecosystems. Top-down control via grazing pressure by zooplankton also constrains primary production and primary production may simultaneously affect zooplankton. Few studies have addressed these bidirectional interactions. We used convergent cross-mapping (CCM), a numerical test of causal associations, to quantify the presence and direction of the causal relationships among environmental variables (light availability, surface water temperature, NO3 -N, and PO4 -P), phytoplankton community composition, primary production, and the abundances of five functional zooplankton groups (large cladocerans, small cladocerans, rotifers, calanoids, and cyclopoids) in Lake Kasumigaura, a shallow, hypereutrophic lake in Japan. CCM suggested that primary production was causally influenced by NO3 -N and phytoplankton community composition; there was no detectable evidence of a causal effect of zooplankton on primary production. Our results also suggest that rotifers and cyclopoids were forced by primary production, and cyclopoids were further influenced by rotifers. However, our CCM suggested that primary production was weakly influenced by rotifers (i.e., bidirectional interaction). These findings may suggest complex linkages between nutrients, primary production, and rotifers and cyclopoids, a pattern that has not been previously detected or has been neglected. We used linear regression analysis to examine the relationships between the zooplankton community and pond smelt (Hypomesus nipponensis), the most abundant planktivore and the most important commercial fish species in Lake Kasumigaura. The relative abundance of pond smelt was significantly and positively correlated with the abundances of rotifers and cyclopoids, which were causally influenced by primary production. This finding suggests that bottom-up linkages between nutrient, primary production, and zooplankton abundance might be a key mechanism supporting high planktivore abundance in eutrophic lakes. Because increases in primary production and cyanobacteria blooms are likely to occur simultaneously in hypereutrophic lakes, our study highlights the need for ecosystem management to resolve the conflict between good water quality and high fishery production.


Asunto(s)
Lagos , Zooplancton , Animales , Ecosistema , Japón , Fitoplancton
18.
Biosci Biotechnol Biochem ; 82(11): 1849-1854, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30096048

RESUMEN

Both light and a redox mediator riboflavin (RF) were utilized to promote the electro-oxidation of an NADH model compound (1-benzyl-1,4-dihydronicotinamide, BNAH), which is a key process for enzymatic biofuel cells to obtain a high performance. At the cathode, H+ ions were simultaneously reduced to produce H2 gas. To elucidate the cell reactions of this photogalvanic cell, which is significant information about the fabrication of enzymatic biofuel cells with a high performance, the effect of the BNAH and RF concentrations on the cell current, the light wavelength dependence on the current, and reduction of the RF concentration were evaluated. The obtained results strongly suggest that the anodic reactions were composed of the following reactions: 1) the photo-excitation of RF, 2) the attack of the excited RF on the BNAH and the generation of the radical species of BNAH and RF, and 3) the chain reactions between the radical species.


Asunto(s)
Electrodos , Luz , Modelos Químicos , NAD/análogos & derivados , NAD/química , Riboflavina/química , Fuentes de Energía Bioeléctrica , Espectroscopía de Resonancia por Spin del Electrón , Transporte de Electrón , Oxidación-Reducción , Espectrofotometría Ultravioleta
19.
Acta Neurochir (Wien) ; 160(10): 1931-1937, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30066190

RESUMEN

BACKGROUND: In surgical treatment of acute subdural hematoma (ASDH), neurosurgeons frequently encounter bleeding from cortical arteries, which is usually controlled with bipolar coagulation. However, bipolar coagulation is associated with a risk of sacrificing the cortical artery, which may affect the prognosis of neurological symptoms when these cortical arteries supply critical areas. In this article, we describe microsurgical repair of damaged cortical arteries using a 10-0 nylon micro-suture in patients with arterial-origin ASDH. METHODS: After removal of the subdural hematoma, the exact bleeding point of the cortical artery was identified, and the 10-0 nylon suture stitches were placed on the arterial tear under a microscope. After completion of the micro-suture, vascular patency was confirmed by indocyanine green (ICG) videoangiography. RESULTS: From June 2015 through February 2017, microsurgical repair was performed for seven cortical arteries in six patients. All damaged arteries were located near the Sylvian fissure, and all tears were pinhole tears. The average blood flow occlusion time was 8 min (range, 0-15 min). The patency of all seven repaired arteries was successfully confirmed by ICG videoangiography. Postoperative cerebral infarction was not observed except in one patient with cerebral contusion and a history of severe head trauma. CONCLUSIONS: The present report demonstrates that repair of a cortical artery by the 10-0 nylon micro-suture is a simple and safe method with a low risk of sacrificing the artery. This technique may be a good option in the surgical treatment of arterial-origin ASDH, especially when the accompanying cerebral contusion is minimal.


Asunto(s)
Arterias Cerebrales/cirugía , Hematoma Subdural Agudo/cirugía , Procedimientos Neuroquirúrgicos/métodos , Técnicas de Sutura , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino
20.
J Theor Biol ; 419: 201-210, 2017 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-28212786

RESUMEN

Filament formation is a common bacterial defense mechanism and possibly has a broad impact on microbial community dynamics. In order to examine the impact of filament formation on population dynamics, we developed an experimental system with a filamentous bacterium Flectobacillus sp. MWH38 and a ciliate predator Tetrahymena pyriformis. In this system, the effective defense of Flectobacillus resulted in the extinction of Tetrahymena by allowing almost no population growth. The result of a kairomone experiment suggested the existence of chemical signals for filament formation. To examine the mechanism further, we developed a quantitative mechanistic model and optimized the model for the experimental result using the simulated annealing method. We also performed a global parameter sensitivity analysis using an approximated Bayesian computation based on the sequential Monte Carlo method to reveal parameters to which the model behavior is sensitive to. Our model reproduced the population dynamics, as well as the cell size dynamics of Flectobacillus. The model behavior is sensitive to the nutrient uptake of Flectobacillus and the propensity of filament formation. It robustly predicts the extinction of Tetrahymena at the condition used in the experiment and predicts the transition from equilibrium to population cycle at higher nutrient conditions. Contrary to the previous study that disproved the presence of chemical signals for filament formation, our result suggested the importance of chemical signals at low predator density, suggesting the variety in bacterial resistance mechanisms that act at different stages of predator-prey interactions.


Asunto(s)
Algoritmos , Cytophagaceae/fisiología , Ecosistema , Modelos Biológicos , Tetrahymena/fisiología , Animales , Teorema de Bayes , Simulación por Computador , Interacciones Microbianas , Método de Montecarlo , Dinámica Poblacional , Crecimiento Demográfico
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