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1.
World J Surg Oncol ; 21(1): 44, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36782222

RESUMEN

BACKGROUND: Recently, there has been an increase in the number of reports of needle tract seeding (NTS) of tumor cells after a biopsy as one of the adverse events related to endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA). In most of the previously reported cases of NTS in pancreatic cancer, distal pancreatectomy was performed as the initial surgery, following which metachronous metastasis was discovered in the gastric wall, whose localization matched the puncture route of the EUS-FNA. We report a case of early metastasis from pancreatic cancer in the gastric wall, which was postulated to be caused by NTS. Our patient underwent a total pancreatectomy (TP), and the NTS was resected synchronously. CASE PRESENTATION: A 70-year-old woman with a diagnosis of pancreatic head-body-tail cancer presented to our department for surgery. Transgastric EUS-FNA and biopsy established the histological diagnosis in her case. We administered neoadjuvant chemotherapy (NAC) to the patient and performed a TP. Histopathological and immunohistochemical examination subsequently confirmed the diagnosis of pT3N1aM1 pancreatic adenocarcinoma and its gastric metastasis, which was caused by NTS. It is postulated that the tumor cells of NTS had progressed to develop the metastatic lesion in the gastric wall during the NAC period. This was also resected during the initial surgery. The patient developed an early postoperative recurrence in the peritoneum 8 months after the surgery. CONCLUSION: In pancreatic head cancer cases, the puncture route is often included in the resection area of radical surgery, and NTS is seldom considered as a potential clinical problem. However, NTS can progress rapidly and may be associated with early recurrence of malignancy. Therefore, when transgastrointestinal puncture is performed for the diagnosis of pancreatic cancer, the treatment strategy should be established considering the potential development of NTS.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Femenino , Anciano , Neoplasias Pancreáticas/patología , Pancreatectomía/efectos adversos , Adenocarcinoma/cirugía , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/efectos adversos , Siembra Neoplásica , Neoplasias Pancreáticas
2.
Surg Today ; 52(11): 1627-1633, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35338428

RESUMEN

PURPOSE: Early management is crucial for acute intestinal blood flow disorders; however, no published study has identified criteria for the time limit for blood flow resumption. This study specifically examines the time factors for avoiding intestinal resection. METHODS: The subjects of this retrospective cohort study were 125 consecutive patients who underwent emergency surgery for a confirmed diagnosis of intestinal strangulation (n = 86), incarceration (n = 27), or volvulus (n = 12), between January 2015 and March 2021. Intestinal resection was performed when intestinal irreversible changes had occurred even after ischemia was relieved surgically. We analyzed the relationship between the time from computed tomography (CT) imaging to the start of surgery (C-S time) and intestinal resection using the Kaplan-Meier method and calculated the estimated intestinal rescue rate. Patient background factors affecting intestinal resection were also examined. RESULTS: The time limit for achieving 80% intestinal rescue rate was 200 min in C-S time, and when this exceeded 300 min, the intestinal rescue rate dropped to less than 50%. Multivariate analysis identified the APACHE II score as a significant influencing factor. CONCLUSION: A rapid transition from early diagnosis to early surgery is critical for patients with acute abdomen originating from intestinal blood flow disorders. The times from presentation at the hospital to surgery should be reduced further, especially for severe cases.


Asunto(s)
Abdomen Agudo , Obstrucción Intestinal , Vólvulo Intestinal , Humanos , Abdomen Agudo/etiología , Abdomen Agudo/cirugía , Factores de Tiempo , Estudios Retrospectivos , Vólvulo Intestinal/diagnóstico por imagen , Vólvulo Intestinal/cirugía , Vólvulo Intestinal/complicaciones , Intestinos/diagnóstico por imagen , Intestinos/cirugía , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía
3.
Hinyokika Kiyo ; 66(7): 235-238, 2020 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-32723979

RESUMEN

A female septuagenarian had poorly controlled diabetes mellitus for more than 20 years. She had persistent pyuria, but did not seek further examination. In 2019, she was transported to our hospital by ambulance for sudden abdominal pain. Physical examination showed a sign of panperitonitis with sepsis. Computed tomography showed ascites and intraperitoneal free air. In addition, there was also a defect in the bladder wall, suggesting bladder rupture. Blood tests showed a marked increase in serum creatinine in addition to increased inflammatory reactants. Because perforation of gastrointestinal tract could not be excluded, an emergency laparotomy was performed. An intraperitoneal perforation of the posterior wall of the bladder was revealed, though there was no intestinal damage. The bladder wall was repaired and cystostomy was performed followed by irrigation and drainage of the abdominal cavity. After the operation, her abdominal symptom resolved and her general status improved. We speculated that voiding disturbance due to neurogenic bladder associated with diabetes mellitus and chronic infection caused the spontaneous bladder rupture. Most cases of spontaneous bladder rupture are associated with a history of pelvic surgery or irradiation, which suggests that this case is extremely rare. In patients with repeated urinary tract infection and underlying disease affecting bladder function, evaluation and appropriate management of bladder dysfunction should be performed ; otherwise, spontaneous bladder rupture may occur.


Asunto(s)
Enfermedades de la Vejiga Urinaria , Vejiga Urinaria Neurogénica , Cistostomía , Femenino , Humanos , Rotura Espontánea
4.
World J Surg Oncol ; 17(1): 76, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31039791

RESUMEN

BACKGROUND: Portal annular pancreas (PAP) is a rare congenital anatomical abnormality of the pancreas in which the portal vein is encircled by aberrant parenchyma, and special attention is needed for pancreatic resections. This is the first report of central pancreatectomy (CP) in a PAP for metastatic renal cell carcinoma (RCC). CASE PRESENTATION: A 76-year-old man who had a history of left nephrectomy for renal cancer not otherwise specified 36 years earlier and radical cystectomy for bladder cancer 4 years earlier was incidentally found to have a pancreatic tumor and a liver tumor. The pancreatic tumor was diagnosed as metastasis of clear cell RCC, and the liver tumor was diagnosed as moderately differentiated hepatocellular carcinoma (HCC) on preoperative histological evaluation. Preoperative computed tomography imaging showed a type 3A PAP, in which the main pancreatic duct (MPD) ran ventral to the portal vein (anteportal type), and the aberrant parenchyma was located cranial to the confluence of the portal vein and splenic vein (suprasplenic type). After adhesiotomy and partial liver resection, CP was performed. With intraoperative ultrasound guidance, the aberrant parenchyma of the PAP could be preserved, avoiding additional resection. Thus, two pancreatic transections were performed, creating a single-cut margin that contained the MPD in the distal pancreas. Oncologically safe margins were confirmed by intraoperative pathological diagnosis. The distal pancreas was reconstructed by pancreatojejunostomy in the routine procedures. The pathological diagnosis of the surgical specimens was identical to the preoperative diagnosis. A postoperative pancreatic fistula (POPF) developed from the proximal stump of the head of the pancreas, necessitating no specific treatment other than drainage. The patient showed no signs or symptoms of recurrent RCC or abnormal pancreatic function for 2 years after the operation, although a histologically proven new HCC lesion developed distant from the initial site 8 months after the operation. CONCLUSIONS: Precise preoperative evaluation of the tumor features and PAP allowed adequate surgical strategies to be planned. Intraoperative ultrasound was useful to minimize parenchymal resections of the PAP. CP is still a challenging procedure in terms of the development of POPF.


Asunto(s)
Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Páncreas/anomalías , Pancreatectomía/métodos , Enfermedades Pancreáticas/cirugía , Vena Porta/cirugía , Complicaciones Posoperatorias , Anciano , Carcinoma de Células Renales/secundario , Humanos , Neoplasias Renales/patología , Masculino , Páncreas/patología , Páncreas/cirugía , Enfermedades Pancreáticas/patología , Vena Porta/patología , Pronóstico
5.
Appl Environ Microbiol ; 80(4): 1394-402, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24334665

RESUMEN

Insertion sequences (ISs) are the simplest transposable elements and are widely distributed in bacteria; however, they also play important roles in genome evolution. We recently identified a protein called IS excision enhancer (IEE) in enterohemorrhagic Escherichia coli (EHEC) O157. IEE promotes the excision of IS elements belonging to the IS3 family, such as IS629, as well as several other families. IEE-mediated IS excision generates various genomic deletions that lead to the diversification of the bacterial genome. IEE has been found in a broad range of bacterial species; however, among sequenced E. coli strains, IEE is primarily found in EHEC isolates. In this study, we investigated non-EHEC pathogenic E. coli strains isolated from domestic animals and found that IEE is distributed in specific lineages of enterotoxigenic E. coli (ETEC) strains of serotypes O139 or O149 isolated from swine. The iee gene is located within integrative elements that are similar to SpLE1 of EHEC O157. All iee-positive ETEC lineages also contained multiple copies of IS629, a preferred substrate of IEE, and their genomic locations varied significantly between strains, as observed in O157. These data suggest that IEE may have been transferred among EHEC and ETEC in swine via SpLE1 or SpLE1-like integrative elements. In addition, IS629 is actively moving in the ETEC O139 and O149 genomes and, as in EHEC O157, is promoting the diversification of these genomes in combination with IEE.


Asunto(s)
Elementos Transponibles de ADN , Escherichia coli Enterotoxigénica/genética , Escherichia coli Enterotoxigénica/aislamiento & purificación , Proteínas de Escherichia coli/genética , Animales , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli Enterotoxigénica/clasificación , Genotipo , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Serotipificación , Porcinos
6.
Radiol Phys Technol ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888821

RESUMEN

In positron emission tomography (PET), measurements of depth-of-interaction (DOI) information and time-of-flight (TOF) information are important. DOI information reduces the parallax error, and TOF information reduces noise by measuring the arrival time difference of the annihilation photons. Historically, these have been studied independently, and there has been less implementation of both DOI and TOF capabilities because previous DOI detectors did not have good TOF resolution. However, recent improvements in PET detector performance have resulted in commercial PET scanners achieving a coincidence resolving time of around 200 ps, which result in an effect even for small objects. This means that TOF information can now be utilized even for a brain PET scanner, which also requires DOI information. Therefore, various methods have been proposed to obtain better DOI and TOF information. In addition, the cost of PET detectors is also an important factor to consider, since several hundred detectors are used per PET scanner. In this paper, we review the latest DOI-TOF detectors including the history of detector development. When put into practical use, these DOI-TOF detectors are expected to contribute to the improvement of imaging performance in brain PET scanners.

7.
Phys Med Biol ; 69(12)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38815615

RESUMEN

Objective. Time-of-flight (TOF) is an important factor that directly affects the image quality of PET systems, and various attempts have been made to improve the coincidence resolving time (CRT) of PET detectors. For independent readout detectors, the timing is acquired for each silicon photomultiplier (SiPM), so they are less sensitive to diffused scintillation light, resulting in a better CRT. Further improvement can be expected if the light can be focused on a single SiPM. However, existing SiPM arrays have a thin protective cover on the SiPM and the gap between the SiPMs is filled with either air or the protective cover, so the light must diffuse through the cover. In this work, we investigated optical crosstalk in the protective cover to improve the CRT.Approach. We used 3.1 × 3.1 × 20 mm3fast LGSO crystals and 3 mm square 8 × 8 multi pixel photon counter (MPPC) arrays. Pitch of the MPPCs was 3.2 mm and thickness of the protective cover on them was 150µm. To reduce diffusion of scintillation light in the protective cover, the part of the inactive areas on the MPPC array were optically separated using reflective material. Specifically, 50, 100, 150, and 350µm deep grid-shaped slits were made along the inactive area of the MPPCs and they were filled with BaSO4powder as the reflective material.Main results. Coincidence counts were measured with a pair of TOF detectors, and the CRT was shorter with a deeper slit depth. The CRT before improvement was 235 ps, and using the cover having the 350µm deep slits filled with reflective material lowered the CRT to 211 ps.Significance. Up to 10% of the scintillation light was diffused to other MPPCs by the protective cover, and the CRT was degraded by 10% due to optical crosstalk of the cover. The proposed method promises to improve the CRT of the TOF detector.


Asunto(s)
Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/instrumentación , Fenómenos Ópticos , Conteo por Cintilación/instrumentación , Factores de Tiempo , Fotones
8.
J Chem Theory Comput ; 20(3): 1185-1192, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38314701

RESUMEN

Full configuration interaction (FCI) can provide an exact molecular ground-state energy within a given basis set and serve as a benchmark for approximate methods in quantum chemical calculations, including the emerging variational quantum eigensolver. However, its exponential computational and memory requirements easily exceed the capability of a single server and limit its applicability to large molecules. In this paper, we present a distributed FCI implementation employing a hybrid parallelization scheme with multithreading and multiprocessing to expand FCI's applicability. We optimize this scheme to minimize the bottlenecks arising from interprocess communications and interthread data management. Our implementation achieves higher scalability than the naive combination of prior works and successfully calculates the exact energy of C3H8/STO-3G with 1.31 trillion determinants, which is the largest FCI calculation to the best of our knowledge. Furthermore, we provide a comprehensive list of FCI results with 136 combinations of molecules and basis sets for future evaluation and development of approximate methods.

9.
Phys Med Biol ; 69(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38776943

RESUMEN

Objective.To compare the accuracy with which different hadronic inelastic physics models across ten Geant4 Monte Carlo simulation toolkit versions can predict positron-emitting fragments produced along the beam path during carbon and oxygen ion therapy.Approach.Phantoms of polyethylene, gelatin, or poly(methyl methacrylate) were irradiated with monoenergetic carbon and oxygen ion beams. Post-irradiation, 4D PET images were acquired and parent11C,10C and15O radionuclides contributions in each voxel were determined from the extracted time activity curves. Next, the experimental configurations were simulated in Geant4 Monte Carlo versions 10.0 to 11.1, with three different fragmentation models-binary ion cascade (BIC), quantum molecular dynamics (QMD) and the Liege intranuclear cascade (INCL++) - 30 model-version combinations. Total positron annihilation and parent isotope production yields predicted by each simulation were compared between simulations and experiments using normalised mean squared error and Pearson cross-correlation coefficient. Finally, we compared the depth of the maximum positron annihilation yield and the distal point at which the positron yield decreases to 50% of peak between each model and the experimental results.Main results.Performance varied considerably across versions and models, with no one version/model combination providing the best prediction of all positron-emitting fragments in all evaluated target materials and irradiation conditions. BIC in Geant4 10.2 provided the best overall agreement with experimental results in the largest number of test cases. QMD consistently provided the best estimates of both the depth of peak positron yield (10.4 and 10.6) and the distal 50%-of-peak point (10.2), while BIC also performed well and INCL generally performed the worst across most Geant4 versions.Significance.The best predictions of the spatial distribution of positron annihilations and positron-emitting fragment production along the beam path during carbon and oxygen ion therapy was obtained using Geant4 10.2.p03 with BIC or QMD. These version/model combinations are recommended for future heavy ion therapy research.


Asunto(s)
Método de Montecarlo , Electrones/uso terapéutico , Radioterapia de Iones Pesados/métodos , Tomografía de Emisión de Positrones , Fantasmas de Imagen
10.
Psychiatry Clin Neurosci ; 67(6): 397-404, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23890055

RESUMEN

AIM: The present study examined the effect of irritable bowel syndrome (IBS), cognitive appraisal of IBS, and anxiety sensitivity on anticipatory anxiety (AA) and agoraphobia (AG) in patients with panic disorder (PD). METHODS: We examined 244 PD patients who completed a set of questionnaires that included the Rome II Modular Questionnaire to assess the presence of IBS, the Anxiety Sensitivity Index (ASI), the Cognitive Appraisal Rating Scale (CARS; assessing the cognitive appraisal of abdominal symptoms in four dimensions: commitment, appraisal of effect, appraisal of threat, and controllability), and items about the severity of AA and AG. The Mini International Neuropsychiatric Interview was used to diagnose AG and PD. RESULTS: After excluding individuals with possible organic gastrointestinal diseases by using 'red flag items,' valid data were obtained from 174 participants, including 110 PD patients without IBS (PD/IBS[-]) and 64 with IBS (PD/IBS[+]). The PD/IBS[+] group had higher AA and higher comorbidity with AG than the PD/IBS[-] group. In the PD/IBS[+] group, the controllability score of CARS was significantly correlated with AA and ASI. Multiple regression analysis showed a significant effect of ASI but not of controllability on AA in PD/IBS[+] subjects. CONCLUSION: This study suggested that the presence of IBS may be related to agoraphobia and anticipatory anxiety in PD patients. Cognitive appraisal could be partly related to anticipatory anxiety in PD patients with IBS with anxiety sensitivity mediating this correlation.


Asunto(s)
Ansiedad/psicología , Cognición , Síndrome del Colon Irritable/psicología , Trastorno de Pánico/psicología , Adulto , Agorafobia/psicología , Interpretación Estadística de Datos , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Síndrome del Colon Irritable/complicaciones , Masculino , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios
11.
Biomed Phys Eng Express ; 9(5)2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37586333

RESUMEN

Objective. A crosshair light sharing (CLS) PET detector as a TOF-DOI PET detector with high spatial resolution has been developed. To extend that work, a detector calibration method was developed to achieve both higher coincidence resolving time (CRT) and DOI resolution.Approach. The CLS PET detector uses a three-layer reflective material in a two-dimensional crystal array to form a loop structure within a pair of crystals, enabling a CRT of about 300 ps and acquisition of DOI from multi-pixel photon counter (MPPC) output ratios. The crystals were 1.45 × 1.45 × 15 mm3fast LGSO, and the crystal array was optically coupled to an MPPC array. It is important to reduce as many inter-crystal scattering (ICS) events as possible in advance for the accurate detector calibration. DOI information is also expected to improve the CRT because it can estimate the time delay due to the detection depth of crystals.Main results. Using crystal identification and light collection rate of the highest MPPC output reduces the number of ICS events, and CRT is improved by 26%. In addition, CRT is further improved by 13% with a linear correction of time delay as a function of energy. The DOI is ideally estimated from the output ratio of only the MPPC pairs optically coupled to the interacted crystals, which is highly accurate, but the error is large due to light leakage in actual use. The previous method, which also utilizes light leakage to calculate the output ratio, is less accurate, but the error can be reduced. Using the average of the two methods, it is possible to improve the DOI resolution by 12% while maintaining the smaller error.Significance. By applying the developed calibration method, the CLS PET detector achieves the CRT of 251 ps and the DOI resolution of 3.3 mm.


Asunto(s)
Fotones , Tomografía de Emisión de Positrones , Calibración , Tomografía de Emisión de Positrones/métodos
12.
Opt Express ; 20(26): B393-8, 2012 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-23262879

RESUMEN

We demonstrate an integrated 100 GbE receiver optical sub-assembly (ROSA) that incorporates a monolithic four-channel avalanche photodiode (APD) array and a planer lightwave circuit (PLC) based LAN-WDM demultiplexer. A record minimum receiver sensitivity of -20 dBm and 50-km error-free SMF transmission without an optical amplifier have been achieved.

13.
Biomed Phys Eng Express ; 8(2)2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35180713

RESUMEN

Coincidence timing resolution (CTR) is an important parameter in clinical positron emission tomography (PET) scanners to increase the signal-to-noise ratio of PET images by using time-of-flight (TOF) information. Lutetium (Lu) based scintillators are often used for TOF-PET systems. However, the self-radiation of Lu-based scintillators may influence the image quality for ultra-low activity PET imaging. Recently, a gadolinium fine aluminum gallate (Ce:GFAG) scintillation crystal that features a fast decay time (∼55 ns) and no self-radiation was developed. The present study aimed at optimizing the GFAG crystal surface treatment to enhance both CTR and energy resolution (ER). The TOF-PET detector consisted of a GFAG crystal (3.0 × 3.0 × 20 mm3) and a SiPM with an effective area of 3.0 × 3.0 mm2. The timing and energy signals were extracted using a high-frequency SiPM readout circuit and then were digitized using a CAMAC DAQ system. The CTR and ER were evaluated with nine different crystal surface treatments such as partial saw-cut and chemical polishing and the 1-side saw-cut was the best choice among the treatments. The respective CTR and ER of 202 ± 2 ps and 9.5 ± 0.1% were obtained with the 1-side saw-cut; the other 5-side mechanically polished GFAG crystals had respective values which were 18 ps (9.0%) and 1.3% better than those of the all-side mechanically polished GFAG crystal. The chemically polished GFAG crystals also offered enhanced CTR and ER of about 17 ps (8.2%) and 2.1%, respectively, over the mechanically polished GFAG crystals.


Asunto(s)
Fotones , Tomografía de Emisión de Positrones , Aluminio , Lutecio , Tomografía de Emisión de Positrones/métodos , Relación Señal-Ruido
14.
EJNMMI Phys ; 9(1): 69, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209191

RESUMEN

BACKGROUND: To confirm the performance of the first hemispherical positron emission tomography (PET) for the brain (Vrain) that we developed to visualise the small nuclei in the deep brain area, we compared 18F-fluorodeoxyglucose (FDG) brain images with whole-body PET images. METHODS: Ten healthy male volunteers (aged 22-45 years) underwent a representative clinical whole-body PET, followed by Vrain each for 10 min. These two scans were initiated 30 min and 45 min after FDG injection (4.1 ± 0.5 MBq/kg), respectively. First, we visually identified the small nuclei and then compared their standardised uptake values (SUVs) with the participants' age. Next, the SUVs of each brain region, which were determined by applying a volume-of-interest template for anatomically normalised PET images, were compared between the brain images with the Vrain and those with the whole-body PET images. RESULTS: Small nuclei, such as the inferior colliculus, red nucleus, and substantia nigra, were more clearly visualised in Vrain than in whole-body PET. The anterior nucleus and dorsomedial nucleus in the thalamus and raphe nucleus in the brainstem were identified in Vrain but not in whole-body PET. The SUVs of the inferior colliculus and dentate gyrus in the cerebellum positively correlated with age (Spearman's correlation coefficient r = 0.811, p = 0.004; r = 0.738, p = 0.015, respectively). The SUVs of Vrain were slightly higher in the mesial temporal and medial parietal lobes than those in whole-body PET. CONCLUSIONS: This was the first time that the raphe nuclei, anterior nuclei, and dorsomedial nuclei were successfully visualised using the first hemispherical brain PET. TRIAL REGISTRATION  : Japan Registry of Clinical Trials, jRCTs032210086, Registered 13 May 2021, https://jrct.niph.go.jp/latest-detail/jRCTs032210086 .

15.
Org Lett ; 24(44): 8228-8232, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36305771

RESUMEN

A synthetic route to ecteinascidin 743 has been established via an intramolecular cascade Heck reaction to construct the diazabicyclo[3.3.1]nonane skeleton while controlling the two contiguous stereogenic centers. The strategically formed five-membered ring was oxidatively cleaved to generate a dialdehyde intermediate, from which the B ring of ecteinascidin 743 was constructed.


Asunto(s)
Alcanos , Ciclización , Estereoisomerismo , Trabectedina
16.
Phys Med Biol ; 67(22)2022 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-36317319

RESUMEN

Objective.For PET imaging systems, a smaller detector ring enables less intrinsic spatial resolution loss due to the photon non-collinearity effect as well as better balance between production cost and sensitivity, and a hemispherical detector arrangement is more appropriate for brain imaging than a conventional cylindrical arrangement. Therefore, we have developed a brain-dedicated PET system with a hemispherical detector arrangement, which has been commercialized in Japan under the product name of VRAINTM. In this study, we evaluated imaging performance of VRAIN.Approach.The VRAIN used 54 detectors to form the main hemispherical unit and an additional half-ring behind the neck. Each detector was composed of a 12 × 12 array of lutetium fine silicate crystals (4.1 × 4.1 × 10 mm3) and a 12 × 12 array of silicon photomultipliers (4 × 4 mm2active area) with the one-to-one coupling. We evaluated the physical performance of VRAIN according to the NEMA NU 2-2018 standards. Some measurements were modified so as to fit the hemispherical geometry. In addition, we performed18F-FDG imaging in a healthy volunteer.Main results.In the phantom study, the VRAIN showed high resolution for separating 2.2 mm rods, 229 ps TOF resolution and 19% scatter fraction. With the TOF gain for a 20 cm diameter object (an assumed head diameter), the peak noise-equivalent count rate was 144 kcps at 9.8 kBq ml-1and the sensitivity was 25 kcps MBq-1. Overall, the VRAIN provided excellent image quality in phantom and human studies. In the human FDG images, small brain nuclei and gray matter structures were clearly visualized with high contrast and low noise.Significance.We demonstrated the excellent imaging performance of VRAIN, which supported the advantages of the hemispherical detector arrangement.


Asunto(s)
Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X , Fantasmas de Imagen , Encéfalo/diagnóstico por imagen
17.
World J Gastroenterol ; 28(8): 868-877, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35317096

RESUMEN

BACKGROUND: During pancreaticoduodenectomy in patients with celiac axis (CA) stenosis due to compression by the median arcuate ligament (MAL), the MAL has to be divided to maintain hepatic blood flow in many cases. However, MAL division often fails, and success can only be determined intraoperatively. To overcome this problem, we performed endovascular CA stenting preoperatively, and thereafter safely performed pancreaticoduodenectomy. We present this case as a new preoperative treatment strategy that was successful. CASE SUMMARY: A 77-year-old man with a diagnosis of pancreatic head cancer presented to our department for surgery. Preoperative assessment revealed CA stenosis caused by MAL. We performed endovascular stenting in the CA preoperatively because we knew that going into the operation without a strategy could lead to ischemic complications. Double-antiplatelet therapy (DAPT) - which is needed when a stent is inserted - was then administered in parallel with neoadjuvant chemotherapy (NAC). This allowed us to administer DAPT for a sufficient period before the main pancreaticoduodenectomy procedure while obtaining therapeutic effects from NAC. Subtotal stomach-preserving pancreaticoduodenectomy was then performed. The operation did not require any unusual techniques and was performed safely. Postoperatively, the patient progressed well, without any ischemic complications. Histopathologically, curative resection was confirmed, and the patient had no recurrence or complications due to ischemia up to six months postoperatively. CONCLUSION: Preoperative endovascular stenting, with NAC and DAPT, is effective and safe prior to pancreaticoduodenectomy in potentially resectable pancreatic cancer.


Asunto(s)
Arteriopatías Oclusivas , Neoplasias Pancreáticas , Anciano , Arteriopatías Oclusivas/etiología , Arteria Celíaca/diagnóstico por imagen , Arteria Celíaca/cirugía , Constricción Patológica/etiología , Humanos , Masculino , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía/efectos adversos
18.
Vet Microbiol ; 273: 109523, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35961275

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is the leading cause of infection in hospitalized patients and can be prevalent in humans and various animal species. In European countries, MRSA isolates belonging to clonal complex 398 have been detected at high rates in pigs. However, the prevalence of MRSA in pigs and farm environments in Japan remains unclear. MRSA isolates were obtained from pigs in slaughterhouses, diseased pigs on farms, imported breeding pigs, and farm dust. We conducted whole-genome sequencing (WGS) and analyzed the molecular epidemiological relationship between these MRSA isolates using core genome multilocus sequence typing (cgMLST). The prevalence rates of MRSA among pigs in slaughterhouses, diseased pigs on farms, imported breeding pigs, and farm dust were 5.2 %, 3.4 %, 28.8 %, and 0.06 %, respectively. ST 398 isolates that classified as ST398/t034 were isolated from pigs from all sources. The results of cgMLST showed that ST398/t034 isolates originating from domestic pigs clustered into the same cluster as the isolates from imported breeding pigs. However, some clusters only included isolates of domestic pig origin. Most MRSA isolates in this study carried resistance genes for aminoglycosides, ß-lactams, macrolides, tetracyclines, and zinc. None of the MRSA isolates in this study harbored Panton-Valentine leukocidin toxin genes. Molecular epidemiological analysis suggested a relationship between isolates from slaughter pigs and imported breeding pigs and the presence of MRSA isolates of domestic origin. However, more data are needed for elucidation of the origin of these MRSA variants in the pig industry in Japan.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Enfermedades de los Porcinos , Animales , Antibacterianos/farmacología , Polvo , Humanos , Japón/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Epidemiología Molecular , Tipificación de Secuencias Multilocus/veterinaria , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/veterinaria , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología
19.
Front Plant Sci ; 13: 1024144, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36743553

RESUMEN

Rice is susceptible to abiotic stresses such as drought stress. To enhance drought resistance, elucidating the mechanisms by which rice plants adapt to intermittent drought stress that may occur in the field is an important requirement. Roots are directly exposed to changes in the soil water condition, and their responses to these environmental changes are driven by photosynthates. To visualize the distribution of photosynthates in the root system of rice plants under drought stress and recovery from drought stress, we combined X-ray computed tomography (CT) with open type positron emission tomography (OpenPET) and positron-emitting tracer imaging system (PETIS) with 11C tracer. The short half-life of 11C (20.39 min) allowed us to perform multiple experiments using the same plant, and thus photosynthate translocation was visualized as the same plant was subjected to drought stress and then re-irrigation for recovery. The results revealed that when soil is drier, 11C-photosynthates mainly translocated to the seminal roots, likely to promote elongation of the root with the aim of accessing water stored in the lower soil layers. The photosynthates translocation to seminal roots immediately stopped after rewatering then increased significantly in crown roots. We suggest that when rice plant experiencing drought is re-irrigated from the bottom of pot, the destination of 11C-photosynthates translocation immediately switches from seminal root to crown roots. We reveal that rice roots are responsive to changes in soil water conditions and that rice plants differentially adapts the dynamics of photosynthates translocation to crown roots and seminal roots depending on soil conditions.

20.
J Hum Genet ; 56(10): 748-50, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21814225

RESUMEN

Panic disorder (PD) is a severe and chronic psychiatric disorder, with genetic components underlying in its etiology. The PERIOD2 (Per2) gene has been reported to be associated with familial advanced sleep phase syndrome. Considering the high frequency of sleep disturbance in PD, Per2 may be a candidate gene for PD. Therefore, we conducted a two-stage case-control association study in the Japanese population. In the first screening sample of 203 patients and 409 controls, we investigated three single-nucleotide polymorphisms in Per2. We found a potential association in the screening sample (rs2304672, genotype P=0.046, uncorrected), whereas we could not replicate the association in the second sample of 460 patients and 460 controls. Our results suggest that Per2 may not have a major role in the pathogenesis of PD in the Japanese population.


Asunto(s)
Pueblo Asiatico/genética , Predisposición Genética a la Enfermedad , Trastorno de Pánico/genética , Proteínas Circadianas Period/genética , Adulto , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Adulto Joven
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