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1.
Small ; 20(30): e2401423, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38770984

RESUMO

Here, strongly orientation-dependent lateral photoconductivity of a CdSe monolayer colloidal quantum wells (CQWs) possessing short-chain ligands is reported. A controlled liquid-air self-assembly technique is utilized to deliberately engineer the alignments of CQWs into either face-down (FO) or edge-up (EO) orientation on the substrate as opposed to randomly oriented (RO) CQWs prepared by spin-coating. Adapting planar configuration metal-semiconductor-metal (MSM) photodetectors, it is found that lateral conductivity spans ≈2 orders of magnitude depending on the orientation of CQWs in the film in the case of utilizing short ligands. The long native ligands of oleic acid (OA) are exchanged with short-chain ligands of 2-ethylhexane-1-thiol (EHT) to reduce the inter-platelet distance, which significantly improved the photoresponsivity from 4.16, 0.58, and 4.79 mA W-1 to 528.7, 6.17, and 94.2 mA W-1, for the MSM devices prepared with RO, FO, and EO, before and after ligands exchange, respectively. Such CQW orientation control profoundly impacts the photodetector performance also in terms of the detection speed (0.061 s/0.074 s for the FO, 0.048 s/0.060 s for the EO compared to 0.10 s/0.16 s for the RO, for the rise and decay time constants, respectively) and the detectivity (1.7 × 1010, 2.3 × 1011, and 7.5 × 1011 Jones for the FO, EO, and RO devices, respectively) which can be further tailored for the desired optoelectronic device applications. Attributed to charge transportation in colloidal films being proportional to the number of hopping steps, these findings indicate that the solution-processed orientation of CQWs provides the ability to tune the photoconductivity of CQWs with short ligands as another degree of freedom to exploit and engineer their absorptive devices.

2.
J Vasc Interv Radiol ; 35(3): 398-403, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38029959

RESUMO

PURPOSE: To investigate the feasibility, safety, and effectiveness of magnetic compression anastomosis of benign short-segment ureteral obstruction. MATERIALS AND METHODS: Patients referred for failure of ureteral double-J stent placement because of impassable benign ureteral obstruction were included. Eleven patients (11 ureters) with a mean age of 57.5 years (range, 19-85 years; 8 women) underwent ureteral magnetic compression anastomosis. All patients had indwelling nephrostomy catheters. In all patients, anterograde and retrograde ureteral stent placements were unsuccessful using either interventional or cystoscopic access. Ureteral magnetic compression anastomosis was performed as a 2-step procedure. In the first step, magnets were placed. In the second step, the stricture was traversed via magnetic compression anastomosis. Successful establishment of anastomosis and ureteral double-J stent placement were considered technical success. The mean time for complete magnetic adherence and fluoroscopy time for each procedure were recorded. RESULTS: Five patients (45%) had an ileal conduit. The technical success rate was 91% (n = 10/11). The mean time for magnetic adherence was 5.7 days (SD ± 1.3). The mean single-rotation fluoroscopy times during the first and second steps of the procedure were 9.45 minutes (SD ± 2.09) and 15.70 minutes (SD ± 2.62), respectively. Magnets were removed with the support of either balloon catheters (n = 9) or biopsy forceps (n = 2). No procedure-related adverse events occurred. CONCLUSIONS: Magnetic compression anastomosis of benign ureteral obstruction is feasible and safe and can be performed in an interventional radiology (IR) suite without the need for endoscopy.


Assuntos
Ureter , Obstrução Ureteral , Derivação Urinária , Humanos , Feminino , Pessoa de Meia-Idade , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/etiologia , Obstrução Ureteral/cirurgia , Derivação Urinária/efeitos adversos , Stents/efeitos adversos , Anastomose Cirúrgica/efeitos adversos , Fenômenos Magnéticos
3.
J Vasc Interv Radiol ; 34(5): 902-909, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36736691

RESUMO

PURPOSE: To evaluate the feasibility of a new technique for imaging-guided de novo retrograde ureteral double J (DJ) stent placement without cystoscopy in women. MATERIALS AND METHODS: Eighty-four women referred for ureteral stent placement between April 2019 and January 2022 were included. In all the patients, the initial attempt for stent placement was performed in a retrograde fashion. Successful ureteral catheterization and DJ stent placement were considered as technical success. The fluoroscopy time required to catheterize the ureter and that for the entire procedure were recorded. Factors affecting the technical success rate and fluoroscopy time were examined. RESULTS: A total of 108 ureteral stent placement procedures in 84 women, with a mean age of 57.5 years (range, 19-85 years), were performed. The most common underlying pathologies were cervical (n = 33, 31%) and ovarian (n = 32, 30%) carcinomas. The most commonly involved segments of the ureter were the lower half (n = 44, 40%) and trigone (n = 39, 36%). The technical success rate was 81.5%, and it reached 93% in the case of lower-half ureteral obstruction. Distorted trigonal anatomy caused by external compression of the bladder wall by a mass was associated with a higher rate of technical failure (90.6% vs 47.8%; P < .001). The use of ultrasound guidance to guide the sheath to the ureteral orifice allowed for a significant decrease in the fluoroscopy time for ureteral catheterization (4.6 minutes ± 3.91 vs 2.26 minutes ± 2.32; P = .003) and that for the entire procedure (9.42 minutes ± 4.95 vs 5.93 minutes ± 4.06; P = .001). CONCLUSIONS: Imaging-guided de novo retrograde ureteral catheterization and stent placement can be successfully performed in a high percentage of patients within a reasonable fluoroscopy time without the need for cystoscopy in women.


Assuntos
Ureter , Obstrução Ureteral , Humanos , Feminino , Pessoa de Meia-Idade , Ureter/diagnóstico por imagem , Cistoscopia , Cateterismo Urinário/métodos , Stents
4.
Parasitol Res ; 121(1): 191-196, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34811587

RESUMO

Cystic Echinococcosis (CE) is a neglected zoonotic disease caused by the metacestode form of Echinococcus granulosus sensu lato. Non-invasive imaging techniques, especially ultrasound, are primarily used for CE diagnosis. MicroRNAs (miRNAs) are small, non-coding RNA molecules that act as post-transcriptional regulators in various biological processes. After identification of parasite-derived miRNAs, these miRNAs are considered to be potential biomarkers for diagnosis and follow-up. The focus of this research is to compare the expression profiles of certain parasite-derived miRNAs in CE patients with active and inactive cysts as well as healthy controls. Parasite-derived miRNAs, egr-let-7-5p, egr-miR-71a-5p, and egr-miR-9-5p, of inactive CE patients were found to be differentially expressed with 3.74-, 2.72-, and 20.78-fold change (p < 0.05), respectively, when compared with active CE patients. In this study, we evaluated for the first time the expression profile of three parasite-derived miRNAs in the serum of CE patients to determine their potential to distinguish between active and inactive CE. It was concluded that serum levels of parasite-derived miRNAs, egr-let-7-5p and egr-miR-9-5p, could be promising new potential biomarkers for stage-specific diagnosis of CE. Further studies are needed with larger sample set to validate discriminating potential of these miRNAs.


Assuntos
Equinococose , Echinococcus granulosus , MicroRNAs , Parasitos , Animais , Biomarcadores , Echinococcus granulosus/genética , Humanos
5.
Environ Dev Sustain ; : 1-27, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36589209

RESUMO

The impacts on food prices of temperature, the oil price, the exchange rate and wages in the agricultural industry were examined via a structural vector autoregression model and panel Granger causality test, using monthly data between January 2003 and December 2020 for Latin American countries. The paper concerns how much the determinants affect food prices. Empirical findings show that the oil price and temperature can be significant factors for reducing food inflation. According to the result of variance decomposition, in general, a considerable part of food inflation was explained by the exchange rate, but its effect did not show any significant change in the long term. The impacts of the oil price and temperature were limited in the early months, but they created larger changes over time. Impulse response function and the Granger causality test also indicated that exchange rate was a crucial dynamic in explaining food inflation in all countries except Ecuador. This country successfully mitigated the negative effect of the exchange rate, but the oil price and temperature had an impact on food inflation. All results indicate that both monetary and fiscal policies are essential to control food prices. These countries can accomplish this by conventional policies or by radical institutional changes. Nevertheless, the oil price and temperature are external dynamics, and crucial in creating alternative policies to control food inflation.

6.
J Vasc Interv Radiol ; 32(6): 890-895.e2, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33727151

RESUMO

PURPOSE: To evaluate the long-term outcomes of percutaneous treatment of renal cystic echinococcosis (CE) stratified by cyst stages according to the World Health Organization (WHO) classification. MATERIALS AND METHODS: Between January 1997 and February 2019, 34 patients with renal CE (18 women; mean age, 38 years) were treated with 3 different percutaneous techniques. According to the World Health Organization classification, the cysts were classified as CE1, CE2, CE3a, and CE3b. Puncture, aspiration, injection, reaspiration (PAIR) or standard catheterization was used for the dimension-based treatment of CE1 and CE3a cysts. Modified catheterization (MoCaT) was used to treat all CE2 and CE3b cysts. Technical and clinical success, complications, and reduction in cyst cavities were evaluated. RESULTS: The technical success rate was 100%. PAIR, standard catheterization, and MoCaT were used to treat 12, 9, and 13 cysts, respectively. The only severe adverse event was a bacterial superinfection that occured in the cyst cavity of a patient (3%) treated with MoCaT. Four patients (12%) experienced mild/moderate periprocedural allergic adverse events and were managed conservatively. The mean length of hospital stay was 1, 5, and 7 days for patients treated with PAIR, standard catheterization, and MoCaT, respectively. The clinical success rate was 97%. In 1 of 34 cysts (3%), recurrence was detected and the cyst was successfully re-treated. During the 10.5-year follow-up period, 95% volume reduction was achieved. The median final cyst volume was 10 mL. CONCLUSIONS: Renal CE can be successfully treated with minimum adverse events and recurrence rates using appropriate percutaneous techniques selected according to their stages as classified according to WHO.


Assuntos
Cateterismo , Drenagem , Equinococose/terapia , Doenças Renais Císticas/terapia , Adulto , Cateterismo/efeitos adversos , Drenagem/efeitos adversos , Equinococose/diagnóstico , Equinococose/parasitologia , Feminino , Humanos , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/parasitologia , Tempo de Internação , Punções , Recidiva , Estudos Retrospectivos , Sucção , Fatores de Tempo , Resultado do Tratamento
7.
Am J Emerg Med ; 38(9): 1966.e1-1966.e3, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32444291

RESUMO

A 53-year-old woman was admitted to the emergency department with sudden onset of massive hemoptysis. She had previous history of dyspnea and cough for two months. She had no history of chronic disease, smoking, or use of anticoagulant and antiplatelet drugs. On arrival, she was tachycardic and tachypneic, but her body temperature was normal. Chest X-ray showed enlarged right hilus and multiple nodular opacities predominantly in the left lung basis. Computed tomography (CT) scan of the chest demonstrated massive intraluminal filling defect extending from the right pulmonary artery through the main and left pulmonary arteries. Pulmonary artery sarcoma (PAS) was the preliminary imaging-based diagnosis. However, CT also revealed presence of several pseudoaneurysms arising from the distal branches of the left pulmonary artery encased by metastatic nodules. Although hemoptysis is an uncommon presentation for patients with PAS, accompanied pseudoaneurysms were the main reason for massive hemoptysis. Differentiation of PAS from bland thromboembolism could be challenging on CT. Herein reported case provides an additional imaging feature that may utilize differentiating pulmonary artery sarcoma from bland thrombus.


Assuntos
Falso Aneurisma/etiologia , Hemoptise/etiologia , Neoplasias de Tecido Vascular/complicações , Artéria Pulmonar , Sarcoma/complicações , Falso Aneurisma/diagnóstico , Serviço Hospitalar de Emergência , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias de Tecido Vascular/diagnóstico , Neoplasias de Tecido Vascular/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Artéria Pulmonar/diagnóstico por imagem , Radiografia Torácica , Sarcoma/diagnóstico , Sarcoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X
8.
AJR Am J Roentgenol ; 212(3): W83-W91, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30620674

RESUMO

OBJECTIVE: The purpose of this study is to evaluate the safety and efficacy of endobiliary radiofrequency ablation (RFA) in the percutaneous management of benign bilioenteric anastomosis strictures that are refractory to balloon dilatation and long-term drainage. MATERIALS AND METHODS: Twenty-one patients (11 men) with a mean age of 47.9 years (range, 26-73 years) underwent percutaneous balloon dilatation and long-term drainage for benign bilioenteric anastomosis strictures. Endobiliary RFA was performed in six patients (four men; mean age, 53.1 years; range, 43-63 years) whose strictures did not respond to balloon dilatation and long-term drainage. RESULTS: Presenting symptoms were jaundice (n = 21), pain (n = 19), pruritus (n = 17), and cholangitis (n = 15). The symptoms appeared 1384 days (range, 4-7592 days) after surgery. The technical success rate was 100%. The overall clinical success rate was 95.2% (20/21) with a mean follow-up of 67.3 months (range, 9-148 months) after catheter removal. In 15 patients, associated biliary stones were removed. Two patients with recurrent strictures were successfully retreated. Endobiliary RFA was successful and catheter removal could be achieved in all six patients (100%) whose disease did not respond to multiple balloon dilatation sessions and long-term drainage. The mean symptom-free period after endobiliary RFA and catheter removal was 430 days (range, 270-575 days). One patient with refractory disease (4.7%), for whom endobiliary RFA was not performed, underwent surgery. There were no major complications. CONCLUSION: Endobiliary ablation may be used safely and effectively in the percutaneous management of benign bilioenteric anastomosis strictures that are refractory to balloon dilatation and long-term drainage, with promising results.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Doenças Biliares/cirurgia , Ablação por Radiofrequência , Adulto , Idoso , Doenças Biliares/etiologia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Dilatação/métodos , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Pediatr Neurosurg ; 54(1): 28-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30673675

RESUMO

OBJECTIVE: To evaluate pediatric patients who were operated with the diagnosis of depressed skull fracture. METHODS: The records of pediatric patients who presented with traumatic head injury to multicenter neurosurgery clinics between 2002 and 2018 and who were operated with a diagnosis of depressed skull fracture were retrospectively reviewed. All of the patients underwent primary bone fragment replacement operation, and the patients' own bone flaps were used to repair depressed skull fractures in all of them. RESULTS: A total of 78 patients were included in the study. Of the study group, 20 patients presented with mild head injury, 37 had moderate head injury, and 21 had severe head injury. Dural injury was present in 67 patients (86%) and the dura was intact in 11 patients (14%). After surgery, 63 patients (81%) had good outcome, 8 patients (10%) had moderate disability, and 5 patients (6.5%) had severe disability. Two patients with multiple accompanying cranial pathologies died and the mortality rate was 2.5%. Infection was detected in only 2 of the 78 patients who were treated within the first 72 h after trauma. One of them had meningitis and the other skin infection. Both patients were treated with appropriate antibiotherapy. None of the patients in the study group had an infection involving the bone, such as osteomyelitis, or the tissues under the bone, such as subdural-epidu-ral empyema or abscess. None of the patients required reoperation and removal of the bone. CONCLUSION: In the present study, as the pathologies accompanying the depressed skull fractures of the patients increased, Glasgow Coma Scale scores at arrival and Glasgow Outcome Scale scores at discharge decreased. Regardless of whether the depressed fracture is simple or compound, primary bone fragment replacement with appropriate decontamination of the fractured bone and operation area via single-session intervention gives good results. It is important to perform the surgery as soon as possible to reduce the risk of contamination. Primary bone fragment replacement seems to be an appropriate treatment option for depressed skull fractures.


Assuntos
Transplante Ósseo/métodos , Fratura do Crânio com Afundamento/diagnóstico por imagem , Fratura do Crânio com Afundamento/cirurgia , Adolescente , Transplante Ósseo/tendências , Criança , Pré-Escolar , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/cirurgia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Retrospectivos , Resultado do Tratamento
10.
Eur Radiol ; 27(8): 3317-3325, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28116514

RESUMO

OBJECTIVE: To determine the diagnostic accuracy of abdominal CT with compression to the right lower quadrant (RLQ) in adults with acute appendicitis. METHODS: 168 patients (age range, 18-78 years) were included who underwent contrast-enhanced CT for suspected appendicitis performed either using compression to the RLQ (n = 71) or a standard protocol (n = 97). Outer diameter of the appendix, appendiceal wall thickening, luminal content and associated findings were evaluated in each patient. Kruskal-Wallis, Fisher's and Pearson's chi-squared tests were used for statistical analysis. RESULTS: There was no significant difference in the mean outer diameter (MOD) between compression CT scans (10.6 ± 1.9 mm) and standard protocol (11.2 ± 2.3 mm) in patients with acute appendicitis (P = 1). MOD was significantly lower in the compression group (5.2 ± 0.8 mm) compared to the standard protocol (6.5 ± 1.1 mm) (P < 0.01) in patients without appendicitis. A cut-off value of 6.75 mm for the outer diameter of the appendix was found to be 100% sensitive in the diagnosis of acute appendicitis for both groups. The specificity was higher for compression CT technique (67.7 vs. 94.9%). CONCLUSION: Normal appendix diameter was significantly smaller in the compression-CT group compared to standard-CT group, increasing diagnostic accuracy of abdominal compression CT. KEY POINTS: • Normal appendix diameter is significantly smaller in compression CT. • Compression could force contrast material to flow through the appendiceal lumen. • Compression CT may be a CT counterpart of graded compression US.


Assuntos
Apendicite/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Abdome , Doença Aguda , Adolescente , Adulto , Idoso , Apendicite/patologia , Apêndice/diagnóstico por imagem , Apêndice/patologia , Distribuição de Qui-Quadrado , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Pressão , Sensibilidade e Especificidade , Adulto Jovem
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