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1.
Proc Natl Acad Sci U S A ; 121(14): e2400868121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547066

RESUMO

Partial cystectomy procedures for urinary bladder-related dysfunction involve long recovery periods, during which urodynamic studies (UDS) intermittently assess lower urinary tract function. However, UDS are not patient-friendly, they exhibit user-to-user variability, and they amount to snapshots in time, limiting the ability to collect continuous, longitudinal data. These procedures also pose the risk of catheter-associated urinary tract infections, which can progress to ascending pyelonephritis due to prolonged lower tract manipulation in high-risk patients. Here, we introduce a fully bladder-implantable platform that allows for continuous, real-time measurements of changes in mechanical strain associated with bladder filling and emptying via wireless telemetry, including a wireless bioresorbable strain gauge validated in a benchtop partial cystectomy model. We demonstrate that this system can reproducibly measure real-time changes in a rodent model up to 30 d postimplantation with minimal foreign body response. Studies in a nonhuman primate partial cystectomy model demonstrate concordance of pressure measurements up to 8 wk compared with traditional UDS. These results suggest that our system can be used as a suitable alternative to UDS for long-term postoperative bladder recovery monitoring.


Assuntos
Bexiga Urinária , Infecções Urinárias , Animais , Humanos , Bexiga Urinária/cirurgia , Urodinâmica/fisiologia , Próteses e Implantes , Cistectomia
2.
Adv Healthc Mater ; 13(5): e2302797, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37983897

RESUMO

Chronic wounds represent a major health risk for diabetic patients. Regeneration of such wounds requires regular medical treatments over periods that can extend for several months or more. Schemes for monitoring the healing process can provide important feedback to the patient and caregiver. Although qualitative indicators such as malodor or fever can provide some indirect information, quantitative measurements of the wound bed have the potential to yield important insights. The work presented here introduces materials and engineering designs for a wireless system that captures spatio-temporal temperature and thermal transport information across the wound continuously throughout the healing process. Systematic experimental and computational studies establish the materials aspects and basic capabilities of this technology. In vivo studies reveal that both the temperature and the changes in this quantity offer information on wound status, with indications of initial exothermic reactions and mechanisms of scar tissue formation. Bioresorbable materials serve as the foundations for versions of this device that create possibilities for monitoring on and within the wound site, in a way that bypasses the risks of physical removal.


Assuntos
Cicatriz , Cicatrização , Humanos , Temperatura , Desenho de Equipamento
3.
Nature ; 596(7870): 68-73, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349290

RESUMO

Key to our understanding of how electrons behave in crystalline solids is the band structure that connects the energy of electron waves to their wavenumber. Even in phases of matter with only short-range order (liquid or amorphous solid), the coherent part of electron waves still has a band structure. Theoretical models for the band structure of liquid metals were formulated more than five decades ago1-15, but, so far, band-structure renormalization and the pseudogap induced by resonance scattering have remained unobserved. Here we report the observation of the unusual band structure at the interface of a crystalline insulator (black phosphorus) and disordered dopants (alkali metals). We find that a conventional parabolic band structure of free electrons bends back towards zero wavenumber with a pseudogap of 30-240 millielectronvolts from the Fermi level. This is wavenumber renormalization caused by resonance scattering, leading to the formation of quasi-bound states in the scattering potential of alkali-metal ions. The depth of this potential tuned by different kinds of disordered alkali metal (sodium, potassium, rubidium and caesium) allows the classification of the pseudogap of p-wave and d-wave resonance. Our results may provide a clue to the puzzling spectrum of various crystalline insulators doped by disordered dopants16-20, such as the waterfall dispersion observed in copper oxides.

4.
J Nucl Med ; 55(8): 1242-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24868109

RESUMO

UNLABELLED: This was a study to compare the diagnostic efficacies of endoscopic ultrasonography (EUS), CT, PET/MR imaging, and PET/CT for the preoperative local and regional staging of esophageal cancer, with postoperative pathologic stage used as the reference standard. METHODS: During 1 y, 19 patients with resectable esophageal cancer were enrolled and underwent preoperative EUS, CT, PET/CT, and PET/MR imaging. A chest radiologist and nuclear medicine physician retrospectively reviewed the images and assigned tumor and lymph node stages according to the seventh version of the TNM system and the American Joint Committee on Cancer staging system. Four patients who were treated nonsurgically were excluded from data analysis. The efficacies of EUS, CT, PET/CT, and PET/MR imaging were compared. RESULTS: Primary tumors were correctly staged in 13 (86.7%), 10 (66.7%), and 5 (33.3%) patients at EUS, PET/MR imaging, and CT, respectively (P value ranging from 0.021 to 0.375). The accuracy of determining T1 lesions was 86.7%, 80.0%, and 46.7% for EUS, PET/MR imaging, and CT, respectively. For distinguishing T3 lesions, the accuracy was 93.3% for EUS and 86.7% for both PET/MR imaging and CT. For lymph node staging, the accuracy was 83.3%, 75.0%, 66.7%, and 50.0% for PET/MR imaging, EUS, PET/CT, and CT, respectively. In addition, area-under-the-curve values were 0.800, 0.700, 0.629, and 0.543 for PET/MR imaging, EUS, PET/CT, and CT, respectively. CONCLUSION: PET/MR imaging demonstrated acceptable accuracy for T staging compared with EUS and, although not statistically significant, even higher accuracy than EUS and PET/CT for prediction of N staging. With adjustments in protocols, PET/MR imaging may provide an important role in preoperative esophageal cancer staging in the future.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Período Pré-Operatório , Idoso , Endossonografia , Neoplasias Esofágicas/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
5.
Korean J Gastroenterol ; 58(3): 144-8, 2011 Sep 25.
Artigo em Coreano | MEDLINE | ID: mdl-21960102

RESUMO

Neuroendocrine tumors are usually found in the ileum, appendix, rectum, colon and stomach. Ampullary neuroendocrine tumor is extremely rare and only a few cases of neuroendocrine carcinoma of the minor papilla have been reported. The preoperative diagnosis is very challenging because either asymptomatic or manifests as nonspecific abdominal pain. The tumor is relatively small and located at the deep mucosa and submucosa. Endoscopy with deep biopsy, endoscopic retrograde cholangiopancreatography and endoscopic ultrasonography are good diagnostic tools. The best therapeutic choice is surgery. We report an unusual case of a 55-year-old woman who underwent endoscopy as part of a regular health checkup and was diagnosed a neuroendocrine carcinoma in the minor papilla, which was successfully resected by pancreaticoduodenectomy. (Korean J Gastroenterol 2011;58:144-148).


Assuntos
Carcinoma Neuroendócrino/diagnóstico , Neoplasias Duodenais/diagnóstico , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/patologia , Neoplasias Duodenais/diagnóstico por imagem , Neoplasias Duodenais/patologia , Duodenoscopia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pancreaticoduodenectomia , Tomografia Computadorizada por Raios X , Ultrassonografia
6.
Int J Mol Med ; 28(2): 255-60, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21567078

RESUMO

The hepatitis B virus X (HBX) protein, a regulatory protein of the hepatitis B virus (HBV), has been shown to generate reactive oxygen species (ROS) in human liver cell lines; however, the mechanism by which cells protect themselves under this oxidative stress is poorly understood. Here, we show that HBX induces the up-regulation of Forkhead box class O 4 (Foxo4) not only in Chang cells stably expressing HBX (Chang-HBX) but also in primary hepatic tissues from HBX-transgenic mice. HBX also increased ROS, but reduction of the abundance of ROS using N-acetylcystein (NAC) diminished the levels of Foxo4. Elevated Foxo4 was also detected in nuclei of Chang-HBX cells but not in Chang cells stably expressing the vector (Chang-Vec), suggesting that HBX activates the transcriptional activity of Foxo4. When we examined whether HBX bypasses JNK signaling that targets Foxo4, we found that the activity of JNK but not of ERK is required for the up-regulation of Foxo4 even in the presence of HBX. Furthermore, the reduction of Foxo4 levels using siRNA or a JNK inhibitor rendered Chang-HBX cells sensitive to apoptosis under oxidative stress, suggesting that up-regulation of Foxo4 mediated by HBX enhances resistances to oxidative stress-induced cell death. Accordingly, we propose that Foxo4 may be a useful target for suppression in the treatment of HBV-associated hepatocellular carcinoma cells.


Assuntos
Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Estresse Oxidativo/genética , Transativadores/genética , Transativadores/metabolismo , Regulação para Cima , Animais , Morte Celular , Linhagem Celular , Núcleo Celular/metabolismo , Fatores de Transcrição Forkhead/antagonistas & inibidores , Regulação da Expressão Gênica , Humanos , MAP Quinase Quinase 4/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transporte Proteico/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Virais Reguladoras e Acessórias
7.
Korean J Gastroenterol ; 57(3): 184-8, 2011 Mar.
Artigo em Coreano | MEDLINE | ID: mdl-21519167

RESUMO

Menetrier's disease is a rare entity characterized by large, tortuous gastric mucosal folds. The mucosal folds in Menetrier's disease are often most prominent in the body and fundus. Histologically, massive foveolar hyperplasia (hyperplasia of surface and glandular mucous cells) is noted, which replaces most of the chief and parietal cells. Profuse mucus is usually observed during the endoscopy but there have been few cases that show interesting endoscopic findings such as mucus bridge or water pearl. Herein, we report a case of Menetrier's disease showing mucus bridge by excessive mucus observed during the endoscopy.


Assuntos
Mucosa Gástrica/patologia , Gastrite Hipertrófica/diagnóstico , 2-Piridinilmetilsulfinilbenzimidazóis/uso terapêutico , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Quimioterapia Combinada , Mucosa Gástrica/metabolismo , Gastrite Hipertrófica/patologia , Gastroscopia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Muco/metabolismo , Pantoprazol , Inibidores da Bomba de Prótons/uso terapêutico , Tomografia Computadorizada por Raios X
8.
J Pediatr Surg ; 46(2): e1-3, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21292062

RESUMO

Gastrointestinal motility disorders are induced by various causes in neonates, some of which are not classified. Generally, these disorders can be classified as a neuropathy or myopathy, each of which can be subdivided into a primary or secondary type. We describe a neonate with a rare form of myopathy related to segmental transposition of the smooth muscle of the ileum and a brief review of the relevant literature.


Assuntos
Íleo/patologia , Pseudo-Obstrução Intestinal/etiologia , Pseudo-Obstrução Intestinal/patologia , Músculo Liso/patologia , Miopatias Congênitas Estruturais/complicações , Motilidade Gastrointestinal/fisiologia , Humanos , Íleo/cirurgia , Recém-Nascido , Pseudo-Obstrução Intestinal/cirurgia , Masculino , Músculo Liso/cirurgia , Miopatias Congênitas Estruturais/patologia , Miopatias Congênitas Estruturais/cirurgia
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