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1.
Mol Cell ; 84(20): 4031-4047.e11, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39357514

RESUMEN

Inter-kingdom communication through small molecules is essential to the coexistence of organisms in an ecosystem. In soil communities, the plant root is a nexus of interactions for a remarkable number of fungi and is a source of small-molecule plant hormones that shape fungal compositions. Although hormone signaling pathways are established in plants, how fungi perceive and respond to molecules is unclear because many plant-associated fungi are recalcitrant to experimentation. Here, we develop an approach using the model fungus, Saccharomyces cerevisiae, to elucidate mechanisms of fungal response to plant hormones. Two plant hormones, strigolactone and methyl jasmonate, produce unique transcript profiles in yeast, affecting phosphate and sugar metabolism, respectively. Genetic analysis in combination with structural studies suggests that SLs require the high-affinity transporter Pho84 to modulate phosphate homeostasis. The ability to study small-molecule plant hormones in a tractable genetic system should have utility in understanding fungal-plant interactions.


Asunto(s)
Ciclopentanos , Homeostasis , Lactonas , Oxilipinas , Fosfatos , Reguladores del Crecimiento de las Plantas , Saccharomyces cerevisiae , Lactonas/metabolismo , Fosfatos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Compuestos Heterocíclicos con 3 Anillos/metabolismo , Acetatos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Regulación Fúngica de la Expresión Génica , Transducción de Señal , Modelos Moleculares , Simportadores de Protón-Fosfato/metabolismo , Simportadores de Protón-Fosfato/genética
2.
J Am Chem Soc ; 146(3): 2237-2247, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38196121

RESUMEN

The acetal (O-glycoside) bonds of glycans and glycoconjugates are chemically and biologically vulnerable, and therefore C-glycosides are of interest as more stable analogs. We hypothesized that, if the O-glycoside linkage plays a vital role in glycan function, the biological activities of C-glycoside analogs would vary depending on their substituents. Based on this idea, we adopted a "linkage-editing strategy" for the creation of glycan analogs (pseudo-glycans). We designed three types of pseudo-glycans with CH2 and CHF linkages, which resemble the O-glycoside linkage in terms of bond lengths, angles, and bulkiness, and synthesized them efficiently by means of fluorovinyl C-glycosylation and selective hydrogenation reactions. Application of this strategy to isomaltose (IM), an inducer of amylase expression, and α-GalCer, which activates iNKT cells, resulted in the discovery of CH2-IM, which shows increased amylase production ability, and CHF-α-GalCer, which shows activity opposite that of native α-GalCer, serving as an antagonist of iNKT cells.


Asunto(s)
Galactosilceramidas , Glicósidos , Polisacáridos , Glicosilación , Polisacáridos/química , Amilasas/metabolismo
3.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38894415

RESUMEN

Large vision-language models, such as Contrastive Vision-Language Pre-training (CLIP), pre-trained on large-scale image-text datasets, have demonstrated robust zero-shot transfer capabilities across various downstream tasks. To further enhance the few-shot recognition performance of CLIP, Tip-Adapter augments the CLIP model with an adapter that incorporates a key-value cache model constructed from the few-shot training set. This approach enables training-free adaptation and has shown significant improvements in few-shot recognition, especially with additional fine-tuning. However, the size of the adapter increases in proportion to the number of training samples, making it difficult to deploy in practical applications. In this paper, we propose a novel CLIP adaptation method, named Proto-Adapter, which employs a single-layer adapter of constant size regardless of the amount of training data and even outperforms Tip-Adapter. Proto-Adapter constructs the adapter's weights based on prototype representations for each class. By aggregating the features of the training samples, it successfully reduces the size of the adapter without compromising performance. Moreover, the performance of the model can be further enhanced by fine-tuning the adapter's weights using a distance margin penalty, which imposes additional inter-class discrepancy to the output logits. We posit that this training scheme allows us to obtain a model with a discriminative decision boundary even when trained with a limited amount of data. We demonstrate the effectiveness of the proposed method through extensive experiments of few-shot classification on diverse datasets.

4.
No Shinkei Geka ; 52(2): 263-269, 2024 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-38514115

RESUMEN

With the advent of high-resolution imaging and advancements in computational fluid dynamics(CFD)and computational structural mechanics(CSM)analyses, clinical simulation of endovascular intervention has gradually become feasible. Virtual stents have become indispensable for coil embolization. For braided stents, such as those with low-profile visualized intraluminal support and flow diverters, predicting postplacement elongation and contraction is challenging; however, software development has enabled more precise treatment planning. Additionally, simulations utilizing three-dimensional(3D)printer models can enable realistic simulations of procedures such as intracranial stents and Woven EndoBridge placement. This approach is beneficial for shunt disorders such as arteriovenous malformations and dural arteriovenous fistulas, offering 3D visualization of shunt access routes and intuitive treatment strategy planning, even for beginners. Furthermore, it can be applied to procedures such as open surgical clipping and nidus resection, aiding in the selection of suitable clips and considerations for ideal resection based on nidus curvature. Simulations using CFD, CSM, and 3D printers are crucial for training surgeons and handling new devices. Harnessing medicine-engineering synergy is essential, and regulatory approval(insurance coverage)and appropriate commercialization of simulations are paramount for the future.


Asunto(s)
Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Humanos , Aneurisma Intracraneal/cirugía , Prótesis Vascular , Stents , Programas Informáticos , Embolización Terapéutica/métodos , Resultado del Tratamiento
5.
Nature ; 546(7656): 137-140, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28514440

RESUMEN

Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.

6.
Plant Cell Physiol ; 63(8): 1078-1090, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35660918

RESUMEN

The response regulator RpaB plays a central role in transcriptional regulation of photosynthesis-related genes in cyanobacteria. RpaB is phosphorylated by its cognate histidine kinase Hik33 and functions as both an activator and a repressor under low-light conditions, whereas its phosphorylation level and DNA-binding activity promptly decrease upon the upshift of photon flux density, causing changes in the gene expression profile. In this study, we assessed the possibility of redox regulation of the DNA-binding activity of RpaB in Synechocystis sp. PCC 6803 by the addition of inhibitors of photosynthetic electron transport, 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, or the reducing agent dithiothreitol under different photon flux densities. Analysis of the phosphorylation level of RpaB revealed that reduction of QA and increase in the availability of reducing equivalents at the acceptor side of photosystem I (PSI) can independently trigger dephosphorylation. The redox-state-dependent regulation by an unidentified thiol other than Cys59 of RpaB is prerequisite for the phosphorylation-dependent regulation of the DNA-binding activity. Environmental signals, recognized by Hik33, and metabolic signals recognized as the availability of reducing equivalents, must be integrated at the master regulator RpaB, in order to attain the flexible regulation of acclimatory responses.


Asunto(s)
Synechocystis , Proteínas Bacterianas/metabolismo , ADN/metabolismo , Regulación Bacteriana de la Expresión Génica , Luz , Oxidación-Reducción , Fotosíntesis , Synechocystis/metabolismo
7.
Neurol Sci ; 43(1): 593-601, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33973077

RESUMEN

BACKGROUND: Severe low back pain (LBP) is an occasional complaint in patients with neuromuscular disorders (NMDs). Accurate diagnosis and treatment are required to manage LBP; however, the precise pathophysiology differs for each patient. This study aimed to evaluate the efficacy of lumbar facet joint denervation (FJD) and adjunctive modalities in the treatment of LBP in patients with NMD-associated kyphoscoliosis. METHODS: A total of 16 patients (22 sites) with NMD (bilateral, n = 6; unilateral, n = 10) and LBP treated with lumbar FJD were evaluated. The patients were divided into two groups: those treated with FJD alone (group 1) and those treated with multimodal treatment, including FJD along with radiofrequency ablation for sacroiliac joint pain, piriform muscle block, botulinum toxin injection into the paraspinal muscles, spinal cord stimulation, or any of their combinations (group 2). All patients were followed up for 48 weeks postoperatively. The two groups were compared with respect to the duration required for improvements in LBP by more than 50% (numerical rating scale ≤ 5). RESULTS: There was no significant difference between the groups regarding the age, duration since the onset of Parkinson's syndrome, and radiographic analysis. The effective period of improved pain was greater in group 2 than in group 1 (30.7 vs. 8.4 weeks, P < 0.01). CONCLUSIONS: Multimodal treatment including FJD is safe and relatively effective in patients with NMD-associated kyphoscoliosis. Hence, it is a potential substitute for conventional spinal fixation surgery, which has a higher risk of complications.


Asunto(s)
Dolor de la Región Lumbar , Articulación Cigapofisaria , Terapia Combinada , Desnervación , Humanos , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Articulación Cigapofisaria/diagnóstico por imagen , Articulación Cigapofisaria/cirugía
8.
J Stroke Cerebrovasc Dis ; 31(11): 106790, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36156445

RESUMEN

OBJECTIVES: Early detection of hemorrhagic transformation (HT) in patients with large vessel occlusion (LVO) after endovascular treatment is important for postoperative patient management. We investigated the diagnostic performance of intraoperative cone beam computed tomography (CBCT) with reference standard magnetic resonance imaging (MRI) for detecting HT. MATERIALS AND METHODS: Consecutive patients with LVO treated by endovascular treatment who underwent intraoperative CBCT and postoperative MRI were included. Two observers evaluated all images for the presence of HT. Sensitivity and specificity for detecting HT were calculated with MRI as reference standard. The observers classified HT according to the European Cooperative Acute Stroke Study (ECASS). Inter-method and inter-rater agreement for the detection of HT and for the ECASS classification were assessed using kappa or weighted Brennan-Prediger (wBP) statistics. RESULTS: Images of 106 procedures (94 for anterior circulation) were analyzed. The sensitivity and specificity for detecting HT on CBCT were 0.77 and 0.83, respectively, for all procedures and 0.83 and 0.8, respectively, for anterior circulation. The inter-method agreement for HT detection (κ = 0.63 overall, κ = 0.69 anterior circulation) and ECASS classification (wBP = 0.67 overall, wBP = 0.77 anterior circulation) were substantial. The inter-rater agreement for HT detection (κ = 0.87 overall, κ = 0.85 anterior circulation) and for ECASS classification (wBP = 0.95 overall, wBP = 0.92 anterior circulation) were almost perfect. CONCLUSIONS: The diagnostic performance of CBCT for the detection of HT in stroke patients treated for LVO was acceptable with excellent inter-rater agreement. Intraoperative CBCT may be useful to trigger early interventions if HT is detected, although detailed classifications of HT may be difficult.


Asunto(s)
Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Tomografía Computarizada de Haz Cónico/métodos , Imagen por Resonancia Magnética , Sensibilidad y Especificidad , Estudios Retrospectivos
9.
Angew Chem Int Ed Engl ; 60(41): 22401-22410, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34121297

RESUMEN

Enzymes catalyzing [4+2] cycloaddition have attracted increasing attention because of their key roles in natural product biosynthesis. Here, we solved the X-ray crystal structures of a pair of decalin synthases, Fsa2 and Phm7, that catalyze intramolecular [4+2] cycloadditions to form enantiomeric decalin scaffolds during biosynthesis of the HIV-1 integrase inhibitor equisetin and its stereochemical opposite, phomasetin. Computational modeling, using molecular dynamics simulations as well as quantum chemical calculations, demonstrates that the reactions proceed through synergetic conformational constraints assuring transition state-like substrates folds and their stabilization by specific protein-substrate interactions. Site-directed mutagenesis experiments verified the binding models. Intriguingly, the flexibility of bound substrates is largely different in two enzymes, suggesting the distinctive mechanism of dynamics regulation behind these stereoselective reactions. The proposed reaction mechanism herein deepens the basic understanding how these enzymes work but also provides a guiding principle to create artificial enzymes.


Asunto(s)
Naftalenos/metabolismo , Pirrolidinonas/metabolismo , Tetrahidronaftalenos/metabolismo , Modelos Moleculares , Conformación Molecular , Naftalenos/química , Estereoisomerismo
10.
Ann Rheum Dis ; 79(11): 1492-1499, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32647028

RESUMEN

OBJECTIVES: To collect clinical information and NOD2 mutation data on patients with Blau syndrome and to evaluate their prognosis. METHODS: Fifty patients with NOD2 mutations were analysed. The activity of each NOD2 mutant was evaluated in HEK293 cells by reporter assay. Clinical information was collected from medical records through the attending physicians. RESULTS: The study population comprised 26 males and 24 females aged 0-61 years. Thirty-two cases were sporadic, and 18 were familial from 9 unrelated families. Fifteen different mutations in NOD2 were identified, including 2 novel mutations (p.W490S and D512V); all showed spontaneous nuclear factor kappa B activation, and the most common mutation was p.R334W. Twenty-six patients had fever at relatively early timepoints in the disease course. Forty-three of 47 patients had a skin rash. The onset of disease in 9 patients was recognised after BCG vaccination. Forty-five of 49 patients had joint lesions. Thirty-eight of 50 patients had ocular symptoms, 7 of which resulted in blindness. After the diagnosis of Blau syndrome, 26 patients were treated with biologics; all were antitumour necrosis factor agents. Only 3 patients were treated with biologics alone; the others received a biologic in combination with methotrexate and/or prednisolone. None of the patients who became blind received biologic treatment. CONCLUSIONS: In patients with Blau syndrome, severe joint contractures and blindness may occur if diagnosis and appropriate treatment are delayed. Early treatment with a biologic agent may improve the prognosis.


Asunto(s)
Artritis/tratamiento farmacológico , Artritis/genética , Artritis/patología , Proteína Adaptadora de Señalización NOD2/genética , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/genética , Sarcoidosis/patología , Sinovitis/tratamiento farmacológico , Sinovitis/genética , Sinovitis/patología , Uveítis/tratamiento farmacológico , Uveítis/genética , Uveítis/patología , Adolescente , Adulto , Edad de Inicio , Antirreumáticos/uso terapéutico , Ceguera/epidemiología , Ceguera/etiología , Niño , Preescolar , Femenino , Humanos , Lactante , Japón , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Mutación , Adulto Joven
11.
BMC Musculoskelet Disord ; 21(1): 725, 2020 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33160354

RESUMEN

BACKGROUND: Carpal tunnel syndrome is a common peripheral nerve compression disorder. However, there is no established opinion regarding the predictors of symptom improvement after surgery. This study aimed to identify the predictors of surgical outcomes of severe carpal tunnel syndrome patients. METHODS: In the patients who underwent a carpal tunnel syndrome surgery, we selected the patients who had a preoperative Bland's classification of grade 5 or 6, and assessed for the changes in Bland's classification grade before and after surgery. Those who showed improvement from preoperative grades 5-6 to postoperative grades 1-4 comprised the improvement group. In contrast, those who did not show improvement and had postoperative grades 5 or 6 comprised the non-improvement group. In a nerve conduction study, amplitudes of the compound muscle action potential and sensory nerve action potential of the palms were assessed between the improvement and non-improvement groups. RESULTS: Among the 60 hands of 46 patients who had a preoperative Bland's classification of grade 5 or 6, 49 hands of 37 patients comprised the improvement group, and 11 hands of 9 patients comprised the non-improvement group. The amplitudes of the compound muscle action potential and sensory nerve action potential of the palms before surgery were significantly higher in the improvement group. The degree of improvement in Bland's classification grade was correlated with the degree of clinical symptom improvement. CONCLUSIONS: Amplitudes of compound muscle action potential and sensory nerve action potential before surgery induced by palmar stimulation can predict improvements in nerve conduction study scores and clinical findings after surgical treatment.


Asunto(s)
Síndrome del Túnel Carpiano , Síndrome del Túnel Carpiano/diagnóstico , Síndrome del Túnel Carpiano/cirugía , Mano/cirugía , Humanos , Nervio Mediano , Conducción Nerviosa , Examen Neurológico , Resultado del Tratamiento
12.
Acta Neurochir (Wien) ; 162(11): 2753-2758, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32929543

RESUMEN

BACKGROUND AND OBJECTIVE: The main challenge of bypass surgery of complex MCA aneurysms is not the selection of the bypass type but the initial decision-making of how to exclude the affected vessel segment from circulation. To this end, we have previously proposed a classification for complex MCA aneurysms based on the preoperative angiography. The current study aimed to validate this new classification and assess its diagnostic reliability using the giant aneurysm registry as an independent data set. METHODS: We reviewed the pretreatment neuroimaging of 51 patients with giant (> 2.5 cm) MCA aneurysms from 18 centers, prospectively entered into the international giant aneurysm registry. We classified the aneurysms according to our previously proposed Berlin classification for complex MCA aneurysms. To test for interrater diagnostic reliability, the data set was reviewed by four independent observers. RESULTS: We were able to classify all 51 aneurysms according to the Berlin classification for complex MCA aneurysms. Eight percent of the aneurysm were classified as type 1a, 14% as type 1b, 14% as type 2a, 24% as type 2b, 33% as type 2c, and 8% as type 3. The interrater reliability was moderate with Fleiss's Kappa of 0.419. CONCLUSION: The recently published Berlin classification for complex MCA aneurysms showed diagnostic reliability, independent of the observer when applied to the MCA aneurysms of the international giant aneurysm registry.


Asunto(s)
Angiografía Cerebral , Revascularización Cerebral/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Arteria Cerebral Media/diagnóstico por imagen , Neuroimagen , Humanos , Aneurisma Intracraneal/cirugía , Arteria Cerebral Media/cirugía , Sistema de Registros , Reproducibilidad de los Resultados
13.
J Stroke Cerebrovasc Dis ; 29(12): 105327, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32992207

RESUMEN

PURPOSE: To assess the benefit and radiation dose of four-dimensional (4D) digital subtraction angiography (DSA) - a time resolved three-dimensional (3D) DSA application - to evaluate the flow and architecture of aneurysms and vascular malformations. METHODS: All patients with cerebrovascular disease were considered who underwent 4D-DSA at our institution between January 2015 and February 2016. For the aneurysm patients, we evaluated the image quality in terms of the visualization of contrast flow in the aneurysm on a 3-point scale (excellent, fair and poor). Interrater agreement between two raters was estimated using Cohen's Kappa statistics. For the shunt disease patients, the additional information obtained from the 4D-DSA was described for each disease. The median radiation dose and volume of contrast medium required for the acquisitions were estimated. RESULTS: A total of 173 patients underwent 4D-DSA; 126 intracranial aneurysms, 10 arteriovenous malformations (AVM), 15 dural arteriovenous fistula (dAVF) and 22 other diseases. For aneurysm patients, excellent and fair visualization of the intra-aneurysmal flow was observed in 27.7%, 72.3%, and excellent (κ = 0.9) agreement between the raters was found. For AVM and dAVF patients, 4D-DSA clarified the complex vasculature by viewing the discrete time phase of contrast filling. Median radiation dose for intracranial lesions was 79.6 mGy for 6s 4D-DSA, and 175 mGy for 12s 4D-DSA. The median amount of contrast medium used was 18.0 ml for 6s 4D-DSA and 21.0 ml for 12s 4D-DSA. CONCLUSIONS: 4D-DSA provided additional information regarding intra-aneurysmal flow and contributed to detect different component of nidus or shunt points.


Asunto(s)
Angiografía de Substracción Digital , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Angiografía Cerebral , Circulación Cerebrovascular , Aneurisma Intracraneal/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Malformaciones Vasculares del Sistema Nervioso Central/fisiopatología , Femenino , Humanos , Aneurisma Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Tiempo , Adulto Joven
14.
J Phys Ther Sci ; 32(10): 615-620, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33132518

RESUMEN

[Purpose] We investigated whether patients with early-stage amyotrophic lateral sclerosis can improve their voluntary strength with a physical therapy program. [Participants and Methods] This retrospective case series study at a single university hospital included 13 patients with amyotrophic lateral sclerosis (amyotrophic lateral sclerosis functional rating scale-revised ≥35, modified functional ambulation categories score ≥4). Physical therapy was performed for 3 weeks. We investigated knee extension muscle strength and modified functional ambulation categories scores at the start and end of the therapy and calculated the improvement rate of knee extension muscle strength. We performed a regression analysis of the relationship between knee extension muscle strength at the start of the study and the improvement rate. [Results] The knee extension muscle strength improved significantly; however, the effect size was small (0.13). The modified functional ambulation categories scores did not improve significantly. The knee extension muscle strength at the start of the therapy was negatively correlated with the improvement rate (logarithmic transformed linear regression: adjusted R2=0.27). [Conclusion] A short-duration exercise program improved lower limb muscle strength in patients with early-stage amyotrophic lateral sclerosis. Additionally, we found that patients with weaker lower limb muscle strength at the start of the therapy demonstrated greater improvement at the end of the therapy.

15.
J Neurooncol ; 138(2): 283-290, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29667085

RESUMEN

The treatment strategy for patients with vestibular schwannoma (VS) is controversial, and data concerning the long-term hearing outcomes > 5 years after gamma knife surgery (GKS) are limited. The long-term hearing outcomes after GKS were evaluated in VS patients with hearing preservation. Ninety-two VS patients with a pure tone average (PTA) ≤ 50 dB were evaluated. The median age was 54 years; the median tumor volume was 1.5 cm3. The tumors were treated with a median margin dose of 12 Gy and a median mean cochlear dose of 4.0 Gy. At the time of GKS, 65 patients retained a PTA of 0-30 dB, and 27 had a PTA of 31-50 dB. The median follow-up period was 106 months. At the final follow-up, 2 (2%) developed tumor progression. During the median audiogram follow-up of 83 months, the PTA was ≤ 30 dB in 22 patients (24%) and 31-50 dB in 27 patients (29%); 43 patients (47%) worsened to a PTA > 50 dB. Hearing preservation rates were 66, 57, and 44% at 3, 5, and 10 years, respectively. In multivariate analysis, the mean cochlear dose (P < 0.001) and pre-GKS PTA (P = 0.045) were significant for hearing preservation. GKS was an effective treatment option for VS patients with a PTA ≤ 50 dB. As a lower cochlear dose and better pre-GKS PTA contributed to long-term hearing preservation, prophylactic GKS before hearing deterioration or tumor growth would be a treatment of choice if patients provided informed consent.


Asunto(s)
Audición , Neuroma Acústico/radioterapia , Radiocirugia , Adolescente , Adulto , Anciano , Audiometría de Tonos Puros , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Trastornos de la Audición/diagnóstico , Trastornos de la Audición/etiología , Trastornos de la Audición/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/fisiopatología , Radiocirugia/efectos adversos , Dosificación Radioterapéutica , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
No Shinkei Geka ; 46(6): 481-489, 2018 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-29930209

RESUMEN

BACKGROUND: To date, there have been many publications concerning relationship of meteorological condition and stroke onset. However, little is known about detailed meteorological factors that affect stroke onset. With hospital characteristics that most inpatients at our institution lived around Komaki, we examined the relationship between stroke onset and meteorological factors based on detailed meteorological data of Komaki. MATERIALS AND METHODS: Between April 1, 2012 and March 31, 2015, 1351 stroke patients admitted to Komaki City Hospital were enrolled in this study. These patients were classified into hypertensive intracranial hemorrhage(ICH), subarachnoid hemorrhage(SAH), and cerebral infarction(CI). Meteorological conditions such as season, weather, temperature, atmospheric pressure, and humidity were evaluated as factors that affect stroke onset. RESULTS: The incidence of ICH was lower in summer, and the minimum daily temperature was significantly related to ICH onset. The incidence of SAH was significantly related to the temperature difference compared to that on the previous day. When the mean temperature was lower than that on the previous day, the incidence of SAH was higher. No meteorological factor was found to affected the incidence of CI in this study. CONCLUSIONS: This study indicated that seasons and temperatures affect stroke onset.


Asunto(s)
Estaciones del Año , Accidente Cerebrovascular , Temperatura , Tiempo (Meteorología) , Humanos , Incidencia , Conceptos Meteorológicos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
17.
Angew Chem Int Ed Engl ; 57(31): 9754-9758, 2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-29972614

RESUMEN

Enzyme-catalyzed [4+2] cycloaddition has been proposed to be a key transformation process in various natural product biosynthetic pathways. Recently Fsa2 was found to be involved in stereospecific trans-decalin formation during the biosynthesis of equisetin, a potent HIV-1 integrase inhibitor. To understand the mechanisms by which fsa2 determines the stereochemistry of reaction products, we sought an fsa2 homologue that is involved in trans-decalin formation in the biosynthetic pathway of an enantiomerically opposite analogue, and we found phm7, which is involved in the biosynthesis of phomasetin. A decalin skeleton with an unnatural configuration was successfully constructed by gene replacement of phm7 with fsa2, thus demonstrating enzymatic control of all stereochemistry in the [4+2] cycloaddition. Our findings highlight enzyme-catalyzed [4+2] cycloaddition as a stereochemically divergent step in natural product biosynthetic pathways and open new avenues for generating derivatives with different stereochemistry.


Asunto(s)
Proteínas Fúngicas/metabolismo , Naftalenos/metabolismo , Aldehído-Liasas , Biocatálisis , Reacción de Cicloadición , Proteínas de Escherichia coli , Proteínas Fúngicas/química , Fusarium/enzimología , Conformación Molecular , Naftalenos/química , Estereoisomerismo
18.
J Neurooncol ; 131(3): 517-524, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27832430

RESUMEN

This study aimed to explore the safety and efficacy of multisession gamma knife surgery (GKS) for large brain metastases with a volume of 10 cm3 or larger. Fifty-six patients who had 65 brain metastases with a volume of at least 10 cm3 were treated with multisession GKS. Three-session GKS at a prescription dose of 10 Gy to the tumor margin per session with a 2-week interval between doses was performed in 3 patients. Other patients were treated with 2-session GKS at a prescription dose of 10-13 Gy to the tumor margin per session with an interval of 1-4 weeks. The median tumor volume was 21 cm3. The median survival was 7 months. The 6-, 12-, and 18-month survival rates were 62, 42, and 31%, respectively. The progression-free survival rates at 6, 12, and 18 months were 93, 80, and 74%, respectively. At the time of the first and last GKS sessions, the median tumor volumes were 21 and 15 cm3, respectively, which decreased to 5 cm3 with a median follow-up period of 6 months. Seventy-four percent of evaluated patients who had pre-GKS clinical symptoms obtained symptomatic improvement in a mean interval of 2 months. Multisession GKS was a safe and effective alternative to surgical resection for patients who had brain metastases with a tumor volume of 10 cm3 or larger. Although long-term results remain unclear, multisession GKS may be a suitable palliative treatment to preserve neurological function.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Radiocirugia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiocirugia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
19.
Biochem Biophys Res Commun ; 460(2): 210-5, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25770422

RESUMEN

Tetramic acid containing a decalin ring such as equisetin and phomasetin is one of the characteristic scaffolds found in fungal bioactive secondary metabolites. Polyketide (PKS)-nonribosomal peptide synthetase (NRPS) hybrid enzyme is responsible for the synthesis of the polyketide scaffold conjugated with an amino acid. PKS-NRPS hybrid complex programs to create structural diversity in the polyketide backbone have begun to be investigated, yet mechanism of control of the stereochemistry in a decalin formation via a Diels-Alder cycloaddition remains uncertain. Here, we demonstrate that fsa2, which showed no homology to genes encoding proteins of known function, in the fsa cluster responsible for equisetin and fusarisetin A biosynthesis in Fusarium sp. FN080326, is involved in the control of stereochemistry in decalin formation via a Diels-Alder reaction in the equisetin biosynthetic pathway.


Asunto(s)
Naftalenos/metabolismo , Sintasas Poliquetidas/metabolismo , Pirrolidinonas/metabolismo , Tetrahidronaftalenos/metabolismo , Fusarium/enzimología , Fusarium/genética , Fusarium/metabolismo , Genes Fúngicos , Familia de Multigenes , Estereoisomerismo
20.
Acta Neurochir (Wien) ; 157(11): 1859-65, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26395008

RESUMEN

BACKGROUND: The Giant Intracranial Aneurysm Registry is a multicenter observational trial exclusively focusing on giant intracranial aneurysms (GIA). As no data exist on the interobserver variability in the radiological description of GIA, there is some uncertainty concerning the reliability of the GIA characteristics included in the registry. We have therefore designed a study to test the interobserver variability in the description of the specific GIA characteristics that are examined in the GIA registry. METHODS: Six different raters analyzed imaging of five GIA concerning GIA location, GIA size, GIA shape, GIA thrombosis, and the presence of perianeurysmal edema. Interobserver variability was examined using intraclass correlation and Fleiss' kappa analysis. RESULTS: The intraclass correlation coefficient was 0.99 (95 % CI 0.97-1.0) for the largest GIA diameter and 0.98 (95 % CI 0.94-1.0) for the largest GIA diameter in an axial imaging slice. We found perfect interobserver agreement (Fleiss' kappa 1.00) in the characterization of GIA location and the presence of perianeurysmal edema and almost perfect interobserver agreement for GIA thrombosis (Fleiss' kappa 0.86, 95 % CI 0.63-1.00). Only moderate interobserver agreement was found in the description of GIA shape (Fleiss' kappa 0.50, 95 % CI 0.27-0.73). CONCLUSIONS: While GIA size, location, thrombosis, and the presence of perianeurysmal edema showed excellent interobserver agreement, the description of GIA shape was achieved with only moderate agreement. Data on GIA shape in multicenter studies, like the GIA registry, should therefore be discussed with caution and potentially reassessed in a centralized fashion.


Asunto(s)
Aneurisma Intracraneal/patología , Angiografía por Resonancia Magnética/normas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
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