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3D printing has attracted the interest of researchers due to its creative freedom, low cost, and ease of operation. Because of these features, this technology has produced different types of electroanalytical platforms. Despite their popularity, the thermoplastic composites used for electrode fabrication typically have high electrical resistance, resulting in devices with poor electrochemical performance. Herein, we propose a new strategy to improve the electrochemical performance of 3D-printed electrodes and to gain chemical selectivity towards glucose detection. The approach involves synthesising a nanostructured gold film using an infrared laser source directly on the surface of low-contact resistance 3D-printed electrodes. The laser parameters, such as power, focal distance, and beam scan rate, were carefully optimised for the modification steps. Scanning electronic microscopy and energy-dispersive X-ray spectroscopy confirmed the morphology and composition of the nanostructured gold film. After modification, the resulting electrodes were able to selectively detect glucose, encouraging their use for sensing applications. When compared with a gold disc electrode, the gold-modified 3D-printed electrode provided a 44-fold current increase for glucose oxidation. As proof of concept, the devices were utilised for the non-enzymatic catalytic determination of glucose in drink samples, demonstrating the gold film's catalytic nature and confirming the analytical applicability with more precise results than commercial glucometers.
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3D printers utilize cutting-edge technologies to create three-dimensional objects and are attractive tools for engineering compact microfluidic platforms with complex architectures for chemical and biochemical analyses. 3D printing's popularity is associated with the freedom of creating intricate designs using inexpensive instrumentation, and these tools can produce miniaturized platforms in minutes, facilitating fabrication scaleup. This work discusses key challenges in producing three-dimensional microfluidic structures using currently available 3D printers, addressing considerations about printer capabilities and software limitations encountered in the design and processing of new architectures. This article further communicates the benefits of using three-dimensional structures, including the ability to scalably produce miniaturized analytical systems and the possibility of combining them with multiple processes, such as mixing, pumping, pre-concentration, and detection. Besides increasing analytical applicability, such three-dimensional architectures are important in the eventual design of commercial devices since they can decrease user interferences and reduce the volume of reagents or samples required, making assays more reliable and rapid. Moreover, this manuscript provides insights into research directions involving 3D-printed microfluidic devices. Finally, this work offers an outlook for future developments to provide and take advantage of 3D microfluidic functionality in 3D printing. Graphical abstract Creating three-dimensional microfluidic structures using 3D printing will enable key advances and novel applications in (bio)chemical analysis.
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Prototyping analytical devices with three-dimensional (3D) printing techniques is becoming common in research laboratories. The attractiveness is associated with printers' price reduction and the possibility of creating customized objects that could form complete analytical systems. Even though 3D printing enables the rapid fabrication of electrochemical sensors, its wider adoption by research laboratories is hindered by the lack of reference material and the high "entry barrier" to the field, manifested by the need to learn how to use 3D design software and operate the printers. This review article provides insights into fused deposition modeling 3D printing, discussing key challenges in producing electrochemical sensors using currently available extrusion tools, which include desktop 3D printers and 3D printing pens. Further, we discuss the electrode processing steps, including designing, printing conditions, and post-treatment steps. Finally, this work shed some light on the current applications of such electrochemical devices that can be a reference material for new research involving 3D printing.
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Solitary hamartomatous polyps with identical pathological features of the typical hamartomas of the Peutz-Jegher syndrome are extremely rare. These solitary lesions lack the associated intestinal polyposis, classic mucocutaneous pigmentation, and family history typifying the Peutz-Jegher syndrome. We describe the case of a 31-year-old woman with a giant solitary gastric hamartoma endoscopically diagnosed and laparoscopically resected.
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Pólipos Adenomatosos , Hamartoma , Síndrome de Peutz-Jeghers , Neoplasias Gástricas , Feminino , Humanos , Adulto , Síndrome de Peutz-Jeghers/complicações , Síndrome de Peutz-Jeghers/diagnóstico , Síndrome de Peutz-Jeghers/cirurgia , Neoplasias Gástricas/patologia , Pólipos Intestinais/complicações , Pólipos Intestinais/cirurgia , Pólipos Intestinais/patologia , Hamartoma/diagnóstico por imagem , Hamartoma/cirurgia , Hamartoma/patologiaRESUMO
A simple fabrication method to make electrochemical sensors is reported. The electrodes were fabricated with a commercial filament based on polylactic acid and carbon black (PLA/CB). They were engineered with a three-dimensional (3D) printing pen and poly(methyl methacrylate) template. The optimization parameters included the thickness and diameters of the electrodes. The electrode diameter was restricted by the 3D printing pen's nozzle dimension, and larger diameters generated small cracks on the electrode surface, compromising their analytical signal. The electrode thickness can increase the electrical resistance, affecting their electrochemical response. The fabrication showed reproducibility (RSD = 4%). The electrode surface was easily renewed by sanding the electrodes, making them reusable. Additionally, the proposed sensor provided comparable electrochemical responses over traditional glassy carbon electrodes. Moreover, no (electro)chemical surface treatment was required for sensing applications due to the compromise between the thickness and diameters of the electrodes, effectively translating the filaments' electrical properties to resulting materials. The electrodes' analytical performance was shown for organic and inorganic species, including paraquat, Pb2+, and caffeic acid. As proof of concept, the analytical applicability was demonstrated for total polyphenolic quantification in tea samples. Therefore, this work provides an alternative to fabricating miniaturized electrodes, bringing valuable insights into PLA/CB 3D-printed sensors and opening possibilities for designing electrode arrays. Moreover, the proposed electrodes are promising platforms for paper-based microfluidic systems.
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Paper-based electrochemical analytical devices (ePADs) have gained significant interest as promising analytical units in recent years because they can be fabricated in simple ways, are low-cost, portable, and disposable platforms that can be applied in various fields. In this sense, paper-based electrochemical biosensors are attractive analytical devices since they can promote diagnose several diseases and potentially allow decentralized analysis. Electrochemical biosensors are versatile, as the measured signal can be improved by using mainly molecular technologies and nanomaterials to attach biomolecules, resulting in an increase in their sensitivity and selectivity. Additionally, they can be implemented in microfluidic devices that drive and control the flow without external pumping and store reagents, and improve the mass transport of analytes, increasing sensor sensitivity. In this review, we focus on the recent developments in electrochemical paper-based devices for viruses' detection, including COVID-19, Dengue, Zika, Hepatitis, Ebola, AIDS, and Influenza, among others, which have caused impacts on people's health, especially in places with scarce resources. Also, we discuss the advantages and disadvantages of the main electrode's fabrication methods, device designs, and biomolecule immobilization strategies. Finally, the perspectives and challenges that need to be overcome to further advance paper-based electrochemical biosensors' applications are critically presented.
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Técnicas Biossensoriais , COVID-19 , Nanoestruturas , Infecção por Zika virus , Zika virus , Humanos , COVID-19/diagnóstico , Nanoestruturas/química , Técnicas Biossensoriais/métodos , Dispositivos Lab-On-A-Chip , Teste para COVID-19RESUMO
Paper-based analytical devices (PADs) are powerful platforms for point-of-need testing since they are inexpensive devices fabricated in different shapes and miniaturized sizes, ensuring better portability. Additionally, the readout and detection systems can be accomplished with portable devices, allying with the features of both systems. These devices have been introduced as promising analytical platforms to meet critical demands involving rapid, reliable, and simple testing. They have been applied to monitor species related to environmental, health, and food issues. Herein, an outline of chronological events involving PADs is first reported. This work also introduces insights into fundamental parameters to engineer new analytical platforms, including the paper type and device operation. The discussions involve the main analytical techniques used as detection systems, such as colorimetry, fluorescence, and electrochemistry. It also showed recent advances involving PADs, especially combining optical and electrochemical detection into a single device. Dual/combined detection systems can overcome individual barriers of the analytical techniques, making possible simultaneous determinations, or enhancing the devices' sensitivity and/or selectivity. In addition, this review reports on distance-based detection, which is also considered a trend in analytical chemistry. Distance-based detection offers instrument-free analyses and avoids user interpretation errors, which are outstanding features for analyses at the point of need, especially for resource-limited regions. Finally, this review provides a critical overview of the practical specifications of the recent analytical platforms involving PADs, demonstrating their challenges. Therefore, this work can be a highly useful reference for new research and innovation.
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Biliary lithiasis is common worldwide, affecting almost 20% of the general population, though few experience symptoms. The frequency of choledocholithiasis in patients with symptomatic cholelithiasis is estimated to be 10-33%, depending on patients' age. Unlike gallbladder lithiasis, the medical and surgical treatment of common bile duct stones is uncertain, having changed over the last few years. The prior gold standard treatment for cholelithiasis and choledocholithiasis was open cholecystectomy with bile duct clearance, choledochotomy, and/or surgical sphincterotomy. In the last 10-15 years, new treatment approaches to the complex pathology of choledocholithiasis have emerged with the advent of endoscopic retrograde cholangiopancreatography (ERCP), laparoscopic surgery, and advanced diagnostic procedures. Although ERCP followed by laparoscopic cholecystectomy is the preferred mode of management, a single-step strategy (laparo-endoscopic rendezvous) has gained acceptance due to lesser morbidity and a lower risk of iatrogenic damage. Given the above, a tailored approach relying on careful evaluation of the disease is necessary in order to minimize complication risks and overall costs. Yet, the debate remains open, with no consensus on the superiority of laparo-endoscopic rendezvous to more conventional approaches.
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Colecistectomia Laparoscópica , Coledocolitíase , Cálculos Biliares , Colangiopancreatografia Retrógrada Endoscópica , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Coledocolitíase/diagnóstico por imagem , Coledocolitíase/cirurgia , Cálculos Biliares/complicações , HumanosRESUMO
Laparoscopic sleeve gastrectomy (LSG) is a commonly used procedure in bariatric patients that often has excellent results. Despite its advantages, LSG is burdened by specific intraoperative and postoperative early and late complications. One of the life-threatening complications is gastric fistula, usually treated with a multidisciplinary surgical-endoscopic approach. In case of failure of the latter, alternative nonoperative techniques such as the use of autologous stem cells truly represents an innovative possibility, with only few cases described in literature. Here, we report the case of a 25-year-old man with post-LSG broncho-gastric fistula treated with application of autologous stem cells after the failure of the conventional surgical/endoscopic approach.
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Fístula Brônquica , Fístula Gástrica , Laparoscopia , Obesidade Mórbida , Masculino , Humanos , Adulto , Fístula Gástrica/cirurgia , Fístula Gástrica/complicações , Fístula Brônquica/diagnóstico por imagem , Fístula Brônquica/etiologia , Fístula Brônquica/cirurgia , Obesidade Mórbida/cirurgia , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Estômago/cirurgia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento , Fístula Anastomótica/etiologia , Estudos RetrospectivosRESUMO
We report a case of a 73-year-old woman affected by Lemmel's syndrome, a rare type of obstructive jaundice caused by a periampullary duodenal diverticulum. The patient was admitted to the Emergency Department for pneumonia associated with mild epigastric pain and vomiting. While hospitalized for antibiotic treatment, the appearance of jaundice led us to discover a periampullary duodenal diverticulum by endoscopy and CT scan. The jaundice was successfully managed endoscopically with removal of food debris from the diverticulum.
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Divertículo , Duodenopatias , Icterícia Obstrutiva , Icterícia , Dor Abdominal/etiologia , Idoso , Divertículo/complicações , Divertículo/diagnóstico por imagem , Divertículo/cirurgia , Duodenopatias/complicações , Duodenopatias/diagnóstico por imagem , Feminino , Humanos , Icterícia Obstrutiva/etiologia , SíndromeRESUMO
Duodenal follicular lymphoma (DFL) is a rare variety of non-Hodgkin's lymphoma of the gastrointestinal tract that usually carries a favorable course, recognized as a new entity in 2016. It is usually diagnosed at an early stage located predominantly in the second portion of the duodenum. We report the case of a 74-year-old male patient with epigastric pain in whom gastroscopy revealed white mucosal nodules that were pathologically diagnosed as grade 1-2 DFL. Staging investigations revealed secondary lesions in the spleen and at the base of the tongue together with latero-cervical adenopathy. The tumor was stage IV according to the Lugano staging system. We reviewed the recent (last five years) literature defining the importance of combination therapy in the advanced stage. The patient achieved complete remission of the disease through chemoimmunotherapy following the Rituximab-Bendamustine scheme.
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Linfoma Folicular , Linfoma não Hodgkin , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Duodeno/patologia , Humanos , Linfoma Folicular/diagnóstico , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Masculino , Indução de Remissão , Rituximab/uso terapêuticoRESUMO
We report the case of a 87-year-old woman admitted to our Emergency Department for mild abdominal pain associated with vomiting. An abdominal X-ray showed gas present in the portal venules of the left hepatic lobe, a finding associated with numerous surgical and medical conditions. The patient was successfully managed with conservative treatment. Isolated intrahepatic gas is a rare radiologic finding; emergency surgery should be performed only when there are signs of associated acute intestinal infarction.
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Embolia Aérea/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Idoso de 80 Anos ou mais , Embolia Aérea/terapia , Feminino , Humanos , Tomografia Computadorizada por Raios XRESUMO
Adenocarcinoma as the primary cause of bowel intussusception is uncommon. We describe the case of a 86-year-old patient admitted for ileocecal intussusception due to the presence of adenocarcinoma, located in the ileocecal valve and right colon. The etiologies of intussusception, its diagnosis, and conservative or surgical treatments are discussed, with attention placed on the indications for reduction of the invagination prior to surgical resection.
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Adenocarcinoma/complicações , Doenças do Íleo/etiologia , Neoplasias do Íleo/complicações , Valva Ileocecal , Intussuscepção/etiologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso de 80 Anos ou mais , Feminino , Humanos , Doenças do Íleo/diagnóstico por imagem , Doenças do Íleo/cirurgia , Neoplasias do Íleo/diagnóstico por imagem , Neoplasias do Íleo/patologia , Neoplasias do Íleo/cirurgia , Valva Ileocecal/diagnóstico por imagem , Valva Ileocecal/patologia , Valva Ileocecal/cirurgia , Intussuscepção/diagnóstico por imagem , Intussuscepção/cirurgia , Estadiamento de Neoplasias , Resultado do TratamentoRESUMO
Giant colonic diverticulum, defined as a single diverticulum ≤ 4 cm, is rarely encountered. Due to the high incidence of complications related to the disease, obtaining the correct diagnosis early in the disease course is essential. Diagnosis is usually reached by conventional and cross-sectional abdominal radiography. Treatment decisions should be ideally made by a multidisciplinary discussion among surgeons, interventional radiologists, and the patient. The treatment of choice is the surgical management by open or laparoscopic approach.
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Divertículo do Colo/complicações , Divertículo do Colo/diagnóstico por imagem , Obstrução do Colo da Bexiga Urinária/diagnóstico por imagem , Obstrução do Colo da Bexiga Urinária/etiologia , Idoso , Divertículo do Colo/cirurgia , Feminino , Humanos , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/cirurgia , Obstrução do Colo da Bexiga Urinária/cirurgiaRESUMO
Although many areas of the Italian territory are of volcanic origin, there is not much attention to the prevention of risks due to exposure to Radon gas. This gas is produced during the decay of uranium present in volcanic rocks and, if inhaled, its further decay produces radioactive radiation responsible for damage to lung tissues. It is estimated that these radiations are responsible for 10% of lung cancers. In conditions of poor air exchange, the concentration of Radon gas can easily reach high concentrations, particularly in underground rooms or on the ground floor that are in direct contact with the ground. In these territories, the designers of new buildings do not always consider this risk and the population is also poorly informed on the behavior to be adopted for prevention.
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Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Radônio , Poluentes Radioativos do Ar/análise , Poluentes Radioativos do Ar/toxicidade , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Humanos , Itália , Radônio/análise , Radônio/toxicidadeRESUMO
Pancreatic pseudocysts commonly complicate acute pancreatitis. They can evolve either asymptomatically or with important symptoms. Treatment can be surgical, endoscopic, or percutaneous. The authors present a case report of a 78-year-old man who developed symptoms of an acute abdomen during hospitalization. A CT scan showed two pancreatic pseudocysts (diameters 10 cm and 7.5 cm) that were successfully drained endoscopically. Multiple pancreatic pseudocysts can be treated successfully via an endoscopic approach.
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Drenagem/métodos , Endoscopia do Sistema Digestório , Pseudocisto Pancreático/terapia , Idoso , Antibacterianos/uso terapêutico , Drenagem/instrumentação , Endoscopia do Sistema Digestório/instrumentação , Enterobacter/isolamento & purificação , Humanos , Masculino , Pseudocisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Stents , Resultado do TratamentoRESUMO
INTRODUCTION: Pelvic schwannomas are rare, mostly benign tumors. They are usually asymptomatic until their massive growth compresses adjacent organs. We describe the case of a 53-year-old man with a pelvic schwannoma who initially complained of constipation and urinary retention. AREAS COVERED: We analyzed the clinical presentation, histopathology, diagnostic imaging tools, and the treatment options for pelvic schwannomas, compared with the few other cases reported in the literature. EXPERT COMMENTARY: Pelvic schwannomas are masses that can grow to considerable size, producing symptoms over time. Due to their size and localization, surgery, although difficult, is the only available treatment.
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Neurilemoma/patologia , Neoplasias Pélvicas/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Dedifferentiated liposarcomas are rare; localization of these tumors in the descending colon is extremely uncommon. We describe the case of a 75-year-old man with a dedifferentiated liposarcoma originating from the descending colon that manifested as partial bowel obstruction. The very uncommon presentation of this rare disease contributed to a challenging diagnostic process. The patient was successfully treated by surgical resection of the mass through left hemicolectomy. Although exceptionally unusual, soft tissue sarcomas should be considered in the differential diagnosis for bowel obstruction. Currently, radical resection of the mass is considered to be the first-line treatment.
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Neoplasias do Colo/diagnóstico , Lipossarcoma/diagnóstico , Idoso , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Humanos , Lipossarcoma/patologia , Lipossarcoma/cirurgia , MasculinoRESUMO
INTRODUCTION: Amyloidosis is an uncommon disease caused by the deposition of amyloid fibrils in tissues. This disease does not usually require surgical intervention, which could be warranted in the presence of complications such as bleeding, obstruction, or perforation. We present a case of primary amyloidosis of the colon in a patient affected by polymyositis who underwent Hartmann's procedure after a spontaneous colonic perforation. After 2 months of well-being, the patient underwent two consecutive surgical procedures for stenosis of the ostomy orifice. AREAS COVERED: A review of the literature has been performed, gathering case reports highlighting the distribution of this disease by age, gender, location, and treatment when available. EXPERT COMMENTARY: Gastrointestinal amyloid disease is a rare condition, and it could be considered among the rare causes of intestinal perforation. Timely surgical management is often necessary.
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Amiloidose/patologia , Colectomia , Colite/patologia , Colostomia , Perfuração Intestinal/cirurgia , Idoso , Amiloidose/complicações , Amiloidose/diagnóstico , Colite/diagnóstico , Colite/etiologia , Doenças do Colo/complicações , Doenças do Colo/diagnóstico , Doenças do Colo/patologia , Constrição Patológica , Feminino , Humanos , Perfuração Intestinal/diagnóstico , Perfuração Intestinal/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Estomas Cirúrgicos/patologiaRESUMO
INTRODUCTION: Isolated heterotopic pancreas (HP) as the primary cause of bowel intussusception is extremely rare. We report a case of a 33-year-old female patient with spina bifida admitted to the Emergency Surgical Department for ileal intussusception due to the presence of heterotopic pancreas associated with endometriosis. AREAS COVERED: Symptomatic ileal intussusception for ectopic pancreas is usually associated with overt gastrointestinal blood loss (predominantly melena), abdominal pain, vomiting, and weight loss. Treatment is universally surgical. EXPERT COMMENTARY: Isolated heterotopic pancreas is a rare condition; it should be considered in the differential diagnosis of bowel intussusception.