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1.
Ann Surg Treat Res ; 107(2): 108-119, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39139833

RESUMO

Purpose: The aim of this study was to evaluate the antibacterial efficacy of surface-treated hernia implants modified by a hybrid nanolayer with incorporated Ag, Cu, and Zn cations using the sol-gel method. Methods: The materials (polypropylene, polyester, and polyvinylidene difluoride) were activated by vacuum plasma treatment or UV C radiation, then modified and tested for bacterial strains of Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive). The AATCC 100 (2019) method for quantitative and the ISO 20645 agar plate propagation method for qualitative evaluation of microbiological efficacy were used. The gradual release of incorporated ions was monitored over time in simulated body fluids (blood plasma, peritoneal fluid) and physiological saline using an inductively coupled plasma mass spectrometer. The thickness and the homogeneity of the layers were measured for individual random samples with scanning electron microscope analysis (SEMA) and evaluated with an elemental analysis. Results: Qualitative and quantitative microbiological tests clearly show the great suitability of vacuum plasma and UV C with sol AD30 (dilution 1:1) surface treatment of the implants. The absolute concentration of Ag, Cu, and Zn cations in leachates was very low. SEMA showed a high degree of homogeneity of the layer and only very rare nanocracks by all tested materials appear after mechanical stress. Conclusion: This study confirms that surface treatment of meshes using the sol-gel method significantly increases the antibacterial properties. The nanolayers are sufficiently mechanically resistant and stable and pose no threat to health.

2.
Ther Clin Risk Manag ; 20: 373-379, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912517

RESUMO

Introduction: The management of patients with COVID-19 infection has placed great pressure on the healthcare systems around the world. The aim of this study was to investigate the impact of the COVID-19 pandemic on the treatment outcomes of patients with rectal cancer by comparing them to those of patients with the same diagnosis in the pre-pandemic period. Methods: Retrospective data analysis of patients undergoing multimodal treatment for rectal cancer at the four university hospitals during the COVID-19 pandemic (2020-2021) and the 2-year pre-pandemic period (2018-2019). Results: A total of 693 patients (319 in the pre-pandemic period and 374 in the pandemic period) with rectal cancer were included in the study. The demographic and clinical characteristics of patients in both study periods were comparable, as was the spectrum of surgical procedures. Palliative surgery was more common in the pandemic period (18% vs 13%, p=0.084). The proportion of patients undergoing minimally invasive surgery was higher during the COVID-19 pandemic (p=0.025). There were no statistically significant differences between the study periods in the incidence/severity of post-operative complications, 30-day mortality and length of hospital stay. The number of positive resection margins was similar (5% vs 5%). Based on these results, COVID-19 had no effect on the postoperative morbidity and mortality in patients undergoing surgery for rectal cancer. Neoadjuvant treatment was more common in the pre-pandemic period (50% vs 45%). Long-course RT was predominantly offered in the pre-pandemic period, short-course RT during the pandemic. Significantly shorter "diagnosis-surgery" intervals were observed during the pandemic (23 days vs 33 days, p=0.0002). The "surgery-adjuvant therapy" interval was similar in both analysed study periods (p=0.219). Conclusion: Our study showed, that despite concerns about the COVID-19 pandemic, multimodal treatment of rectal cancer was associated with unchanged postoperative morbidity rates, increased frequency of short-course neoadjuvant RT administration and shorter "diagnosis-surgery" intervals.

3.
Anat Sci Int ; 99(2): 215-220, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37864758

RESUMO

The middle colic artery usually arises from the superior mesenteric artery, but in rare cases it may arise from the coeliac trunk or its branches. The aim of this study was to investigate variant origins of the middle colic artery on computed tomography and anatomical dissection. Variant middle colic arteries were identified on computed tomography as part of an ongoing study investigating anatomical variations of vessels of the upper abdomen. Three-dimensional reconstructions were made to demonstrate the variant findings. Cadaveric dissections were performed as part of a routine dissection course. We report five cases of rare variant origins of the middle colic artery arising from the coeliac axis. Among these sites of origin were the coeliac trunk, the gastrosplenic trunk, the splenic artery, and the common hepatic artery. Four cases were identified on multi-detector computed tomography and one in a cadaver. In all cases, the vessels passed posterior to the body of the pancreas before entering the transverse mesocolon. Knowledge of middle colic artery variations is important to prevent inadvertent injury in digestive surgery, especially in the hepatopancreatic area. Variant origins of the middle colic artery are rare, and their knowledge is crucial to prevent unnecessary iatrogenic injury during abdominal surgery.


Assuntos
Colo Transverso , Artéria Mesentérica Superior , Humanos , Artéria Mesentérica Superior/diagnóstico por imagem , Artéria Mesentérica Inferior , Artéria Celíaca , Artéria Hepática
4.
Wound Repair Regen ; 32(1): 67-73, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38111101

RESUMO

StopBac is an innovative silver-impregnated antimicrobial dressing specifically designed to reduce surgical site infections and enhance healing. The primary objective of this study was to compare infection healing rate at 30 days after surgery between primarily closed surgical wounds covered with StopBac and those covered with Cosmorpor, a standard surgical dressing. Between 1.3.2023 and 30.4.2023, we conducted a prospective screening of all patients undergoing surgical operations within a single surgical department. Patients were randomised into either the Cosmopor group or the StopBac group. Outcome measures were superficial and deep surgical site infections and healed wounds. Data concerning patient and surgical factors were prospectively collected and analysed. The analysis comprised 275 patients, divided into two groups: 140 patients in the StopBac group and 135 in the Cosmopor group. The StopBac dressing was associated with a reduced rate of infection, with an odds ratio of 0.288 (p < 0.001), and an increased likelihood of wound healing at 30 days after surgery. The odds ratio for healing at 30 days was 4.661 (p < 0.001). StopBac was associated with a lower incidence of surgical wound infections and a higher probability of healing at 30 days after surgery, when compared with standard dressing.


Assuntos
Queimaduras , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Prata/farmacologia , Cicatrização , Estudos Prospectivos , Bandagens
5.
Eur Surg Res ; 64(4): 376-389, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37879309

RESUMO

INTRODUCTION: The aim of this work was the evaluation of surface modification in surgery of normally used hernia implants and thus improving their antimicrobial properties. The modification consisted of applying hybrid nanolayers with immobilized antiseptic substances (metal cations of Ag, Cu, and Zn) by sol-gel method which ensures prolonged effect of these substances and thus enables a greater resistance of the implant towards infection. In this work, attention is drawn to the issue of applying hybrid nanolayers, activation of mesh surfaces by physical plasma modification or ultraviolet C (UV C) radiation, and influence of these modifications on the mechanical properties of the final meshes. Next work will continue concentrating on the issue of antimicrobial efficacy and eventual toxicity of the prepared layers. MATERIALS AND METHODS: Present-day materials of the most commonly used types of implants for reconstruction of the abdominal wall in surgery (polypropylene, polyester, polyvinylidenefluoride) were tested. Optimum conditions of application of nanolayers by sol-gel method and their thermal stabilization were examined first. Surface modification was verified by scanning electron microscope. The surface of implants was first activated for better adhesion by plasma treatment or UV radiation after preliminary tests. Maximum strength and ductility after activation and hybrid nanolayer modification were objectively measured on a universal Testometric tensile testing machine. RESULTS: The results of surface activation of the meshes (by both plasma treatment or UV C radiation) provided similar and satisfactory results, and particular conditions differed based on the type of material of the mesh. Usage of antimicrobial sol AD30 diluted by isopropyl alcohol in 1:1 proportion appear to be optimal. All tested cases of meshes activated by plasma treatment or UV C radiation and with applied nanolayer concluded in a slight reduction of mechanical properties in modified meshes in comparison with the original ones. However, a slight reduction of test values was not of clinical importance. CONCLUSION: It was verified that surface modification of implants by sol-gel method is effective and technically possible, providing hopeful results.


Assuntos
Anti-Infecciosos , Anti-Infecciosos/farmacologia , Próteses e Implantes , Telas Cirúrgicas , Teste de Materiais , Resistência à Tração
6.
J Hepatobiliary Pancreat Sci ; 30(12): 1324-1333, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37750364

RESUMO

BACKGROUND: The aim of this study was to compare trends in mortality and incidence, clinicopathological features and survival of patients diagnosed with pancreatic ductal adenocarcinoma under 50 years of age (early-onset pancreatic cancer [EOPC]) with patients diagnosed over 50 years of age (late-onset pancreatic cancer [LOPC]). METHODS: The national oncological registry of the Czech Republic was reviewed to identify all patients with histologically confirmed pancreatic ductal adenocarcinoma diagnosed between the years 1985 and 2015. Incidence, mortality, clinicopathological and survival data were analyzed and compared between patients with EOPC and LOPC. RESULTS: From a total of 18 888 patients included in the study, 1324 patients were under the age of 50 years (7.0%). The average annual percentage changes (AAPC) in incidence of all patients with EOPC was -1.0%. The APPC for male patients with EOPC was -2.0% and for female patients was +0.6%. The AAPC in incidence for LOPC was +1.3%. There were no differences in tumor stage, grade or location between EOPC and LOPC. Young patients were more frequently male (64.4% vs. 52.9%), more frequently underwent treatment and had better overall survival. The median survival interval for EOPC was 5.9 months and for LOPC was 4.5 months (p < .001). CONCLUSIONS: The clinicopathological features of pancreatic ductal adenocarcinoma were similar in patients under and over the age of 50 years. Patients with EOPC survived longer than patients with LOPC. Continued efforts should be made to diagnose early and treat young patients aggressively.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , República Tcheca/epidemiologia , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/diagnóstico , Carcinoma Ductal Pancreático/epidemiologia , Carcinoma Ductal Pancreático/terapia , Sistema de Registros , Incidência
7.
Clin Anat ; 36(8): 1147-1153, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37096869

RESUMO

The aim of this study was to review the literature on the posterior gastric artery, estimate its prevalence and summarize its reported origins. The databases Pubmed, Scopus, Web of Science and Google Scholar were searched to find all studies describing the prevalence and origin of the posterior gastric artery. Pooled prevalences were estimated using a random effects model. Thirty-eight studies with a total of 3366 subjects were included in the analysis. The overall prevalence of the posterior gastric artery was 57.4% (95% CI = 49.1%-65.7%). The prevalence of the posterior gastric artery was significantly higher in surgical studies than in cadaveric and angiographic studies. There were no differences in prevalence between multi-detector computed tomography studies and cadaveric studies, nor were there differences when comparing geographical location or study size. Origin data were extracted from 34 studies, with a total of 1533 cases. The posterior gastric artery arose as a single vessel from the splenic artery in 1160 cases (pooled prevalence 86.5% [95% CI = 78.5%-94.7%]), from the superior polar splenic artery in 339 cases (pooled prevalence 11.8% [95% CI = 3.7%-19.9%]) and from other origins in 50 cases (pooled prevalence 0.27% [95% CI = 0.00-0.71%]). The posterior gastric artery is present in 57.4% of cases and most commonly arises from the splenic artery. It should be identified before gastric resections as it may be an important source of blood to the gastric stump. Multi-detector computed tomography has sufficient sensitivity to detect it before surgery.


Assuntos
Artéria Gástrica , Artéria Esplênica , Humanos , Gastrectomia , Tomografia Computadorizada Multidetectores , Cadáver , Prevalência
8.
J Surg Res ; 288: 233-239, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37030180

RESUMO

INTRODUCTION: Portomesenteric vein resections are a well-established part of pancreatectomies for advanced tumors that invade the portomesenteric axis. There are two main types of portomesenteric resections: partial resections, where only part of the venous wall is removed and segmental resection, where the full circumference of the wall is removed. The aim of this study is to compare short-term and long-term outcomes between these two techniques. METHODS: This is a single-centre retrospective study of the patients with pancreatic cancer who underwent pancreatectomy with portomesenteric vein resections between November 2009 and May 2021. RESULTS: From a total of 773 pancreatic cancer procedures, 43 (6%) patients underwent pancreatectomy with portomesenteric resections: 17 partial and 26 segmental. The overall median survival was 11 mo. For the partial portomesenteric resections, the median survival was 29 mo, and for the segmental portomesenteric resections, it was 10 mo (P = 0.019). The primary patency of the reconstructed veins after partial resection was 100% and after segmental resection was 92% (P = 0.220). Negative resection margins were achieved in 13 patients (76%) who underwent partial portomesenteric vein resection and 23 patients (88%) who underwent segmental portomesenteric vein resection. CONCLUSIONS: |Although this study is associated with worse survival, segmental resection is often the only way to safely remove pancreatic tumors with negative resection margins.


Assuntos
Pancreatectomia , Neoplasias Pancreáticas , Humanos , Pancreatectomia/métodos , Estudos Retrospectivos , Margens de Excisão , Veia Porta/cirurgia , Veia Porta/patologia , Veias Mesentéricas/cirurgia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas
9.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36835029

RESUMO

Therapy for pancreatic ductal adenocarcinoma remains challenging, and the chances of a complete cure are very limited. As in other types of cancer, the expression and role of miRNAs in controlling the biological properties of this type of tumor have been extensively studied. A better insight into miRNA biology seems critical to refining diagnostics and improving their therapeutic potential. In this study, we focused on the expression of miR-21, -96, -196a, -210, and -217 in normal fibroblasts, cancer-associated fibroblasts prepared from a ductal adenocarcinoma of the pancreas, and pancreatic carcinoma cell lines. We compared these data with miRNAs in homogenates of paraffin-embedded sections from normal pancreatic tissues. In cancer-associated fibroblasts and cancer cell lines, miRNAs differed significantly from the normal tissue. In detail, miR-21 and -210 were significantly upregulated, while miR-217 was downregulated. Similar transcription profiles were earlier reported in cancer-associated fibroblasts exposed to hypoxia. However, the cells in our study were cultured under normoxic conditions. We also noted a relation to IL-6 production. In conclusion, cultured cancer-associated fibroblasts and carcinoma cells reflect miR-21 and -210 expression similarly to the cancer tissue samples harvested from the patients.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , Fibroblastos Associados a Câncer/metabolismo , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas
10.
Sci Rep ; 13(1): 1644, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717683

RESUMO

The research of novel implantable medical devices is one of the most attractive, yet complex areas in the biomedical field. The design and development of sufficiently small devices working in an in vivo environment is challenging but successful encapsulation of such devices is even more so. Industry-standard methods using glass and titanium are too expensive and tedious, and epoxy or silicone encapsulation is prone to water ingress with cable feedthroughs being the most frequent point of failure. This paper describes a universal and straightforward method for reliable encapsulation of circuit boards that achieves ISO10993 compliance. A two-part PVDF mold was machined using a conventional 3-axis machining center. Then, the circuit board with a hermetic feedthrough was placed in the mold and epoxy resin was injected into the mold under pressure to fill the cavity. Finally, the biocompatibility was further enhanced with an inert P3HT polymer coating which can be easily formulated into an ink. The biocompatibility of the encapsulants was assessed according to ISO10993. The endurance of the presented solution compared to silicone potting and epoxy potting was assessed by submersion in phosphate-buffered saline solution at 37 °C. The proposed method showed superior results to PDMS and simple epoxy potting.


Assuntos
Resinas Epóxi , Próteses e Implantes , Eletrônica , Água , Silicones
11.
Bratisl Lek Listy ; 123(10): 719-723, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913006

RESUMO

Receptors of the large HER family play an important role in breast cancer, which is undergoing a gradual development in connection with biological development, both in the field of diagnostics and therapy. Dimerization of HER-2 with other HER members, such as HER-3, is the biggest driver of tumor cell growth and survival. Numerous studies show that HER-3 gene overexpression correlates with poor prognosis. However, other studies have shown HER-3 overexpression to be a positive prognostic factor. HER-3 may confer resistance to certain EGFR or HER-2 receptor therapeutics. An interesting fact, however, is that HER-3 expression can serve as a marker in immunotherapy for triple-negative breast cancer (TNBC). It is thought to be involved not only in cell survival and proliferation, but also in the regulation of PD-L1 expression. In breast cancer, PD-L1 expression is heterogeneous and is generally associated with the presence of tumor­infiltrating lymphocytes and a number of factors with poor prognosis such as young age, hormone receptor negativity, and high HER-2 expression and proliferation index. Our results showed amplification of HER-3 (CERB3) in 2 out of a sample of 20 patients with TNBC, and 13 of 20 HER-2­positive patients. PD-L1 expression was demonstrated in 3 out of 13 HER-3­positive patients and 2 out of 2 HER-3­positive TNBC patients. There was a strong correlation between positive HER-3 and PD-L1 TNBC expression (p = Keywords: breast cancer, HER family, overexpression, HER-3, HER-2, PD-L1, TNBC.


Assuntos
Antígeno B7-H1 , Neoplasias de Mama Triplo Negativas , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Prognóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
12.
Surg Infect (Larchmt) ; 23(7): 682-690, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35930248

RESUMO

Background: A new silver-based dressing has been designed to reduce surgical sited infections. Patients and Methods: A prospective multicenter observational study was conducted from January 2020 to October 2021. Patients with and without silver-based dressing after surgical incision were observed and their data analyzed. The study aimed to assess the incidence of incisional surgical site infection and primary healing after general surgery procedures. Results: Overall, 218 patients with silver-based (n = 109) and conventional silver-free dressing (n = 109) were analyzed. Surgical site infection (SSI) and primary incision healing were reported in 10 (9.2%) versus 21 (19.3%) (p = 0.037) and in 95 (87.2%) versus 86 (78.9%) (p = 0.107) patients treated with and without silver-based dressing, respectively. Conclusions: Silver-based dressing demonstrated a lower incidence of incisional SSI and improved primary healing in comparison with patients in whom conventional non-silver-based dressing has been used.


Assuntos
Bandagens , Infecção da Ferida Cirúrgica , Bandagens/efeitos adversos , Humanos , Estudos Prospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle
13.
Pancreatology ; 22(2): 325-332, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35177332

RESUMO

BACKGROUND/OBJECTIVES: The dorsal pancreatic artery is the main artery of the body and tail of the pancreas. Its origin and branching is highly variable. The aim of this study was to perform a meta-analysis to generate pooled prevalence data on the presence and origin of the dorsal pancreatic artery. Clinically important aspects of the dorsal pancreatic artery were summarised during the literature review. METHODS: Major medical databases were searched. Data on the presence and point of origin of the dorsal pancreatic artery were extracted and quantitatively synthesised. The obtained data of anatomical based studies and computed tomography based studies were statistically analysed. RESULTS: In total, 30 studies, comprising 2322 anatomical and computed tomography based cases were included. The dorsal pancreatic artery was present in 95.8% of cases. It originated from the splenic artery in 37.6% of cases, common hepatic artery in 18.3% of cases, coeliac trunk in 11.9% of cases and the superior mesenteric artery in 23.9% of cases. Other rare origins were present in 2.77% of cases. Multiple dorsal pancreatic arteries were found in 1,7% of cases. There was no significant difference in the presence or origin of the dorsal pancreatic artery between anatomical and computed tomography based studies. CONCLUSION: The dorsal pancreatic artery is present in the vast majority of cases. Its origin and branching are highly variable. Multiplicity of the dorsal pancreatic artery is infrequent.


Assuntos
Artéria Celíaca , Artéria Esplênica , Humanos , Artéria Mesentérica Superior , Pâncreas/irrigação sanguínea , Pâncreas/diagnóstico por imagem , Artéria Esplênica/diagnóstico por imagem , Tomografia Computadorizada por Raios X
14.
Int Wound J ; 19(1): 29-35, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33773060

RESUMO

Ideal dressings of surgical wounds should provide moist, semi-permeable, and antiseptic environments for optimal wound healing. To maximise patient comfort, surgical dressings must be hypoallergenic, not restrict movement, and allow patients to manage their personal hygiene. From the aspect of health care personnel, dressings should enable visual monitoring of the wound without the need for removing them, thus reducing the number of dressing changes. The active antimicrobial effect of silver cations has been demonstrated by many studies. StopBac is a unique surgical dressing based on the sol-gel process. Silver cations are bound in a colloidal solution in an organic-inorganic hybrid organosilicate oligomer. This gel is deposited on a pad using spray atomisation. The result is a polymer nanolayer matrix with prolonged and controlled release of silver ions. This pad forms part of a waterproof hypoallergenic transparent adhesive bandage. The goal of this study was to prospectively evaluate the ability of StopBac to prevent surgical site infections (SSIs) in patients after abdominal surgery. The secondary goal was to compare costs and determine the properties of this new material. A total of 32 patients were included in the study. The patients were followed up until their surgical wounds healed completely. An SSI occurred only in one patient.


Assuntos
Prata , Infecção da Ferida Cirúrgica , Bandagens , Remoção de Dispositivo , Humanos , Prata/uso terapêutico , Infecção da Ferida Cirúrgica/prevenção & controle , Cicatrização
15.
J Healthc Eng ; 2021: 9986874, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603652

RESUMO

Radiofrequency ablation (RFA) is a routinely used, safe, and effective method for the tissue destruction. Often, in case of its application in malignant conditions, the extent of tissue destruction is insufficient due to the size of the target lesion, as well as due to the risk of heat-induced damage to the surrounding organs. Nevertheless, there are conditions requiring superficial precise-depth ablation with preservation of deeper layers. These are represented, for example, by mucosal resurfacing in case of Barrett's esophagus or treatment of recurrent mucosal bleeding in case of chronic radiation proctitis. Recently, new indications for intraluminal RFA use emerged, especially in the pancreatobiliary tract. In the case of intraductal use of RFA (e.g., biliary and pancreatic tract), there are currently available rigid and needle tip catheters. An expandable balloon-based RFA catheter suitable for use in such small-diameter tubular organs could be of benefit due to possible increase of contact between the probe and the target tissue; however, to prevent excessive tissue damage, a compatible generator suitable for low-impedance catheter/tissue is essential. This project aimed to develop a radiofrequency ablation generator and bipolar balloon-based catheter optimized for the application in the conditions of low-impedance tissue and (micro)endoluminal environment. Subsequent evaluation of biological effect in vivo was performed using duodenal mucosa in Wistar rat representing conditions of endoluminal radiofrequency ablation of low-impedance tissue. Experiments confirming the safety and feasibility of RFA with our prototype devices were conducted.


Assuntos
Ablação por Radiofrequência , Animais , Catéteres , Duodeno/cirurgia , Impedância Elétrica , Ratos , Ratos Wistar , Resultado do Tratamento
16.
J Vis Exp ; (174)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34515682

RESUMO

Ambulatory pH monitoring of pathological reflux is an opportunity to observe the relationship between symptoms and exposure of the esophagus to acidic or non-acidic refluxate. This paper describes a method for the development, manufacturing, and implantation of a miniature wireless-enabled pH sensor. The sensor is designed to be implanted endoscopically with a single hemostatic clip. A fully passive rectenna-based receiver based on a zero-bias Schottky diode is also constructed and tested. To construct the device, a two-layer printed circuit board and off-the-shelf components were used. A miniature microcontroller with integrated analog peripherals is used as an analog front end for the ion-sensitive field-effect transistor (ISFET) sensor and to generate a digital signal which is transmitted with an amplitude shift keying transmitter chip. The device is powered by two primary alkaline cells. The implantable device has a total volume of 0.6 cm3 and a weight of 1.2 grams, and its performance was verified in an ex vivo model (porcine esophagus and stomach). Next, a small footprint passive rectenna-based receiver which can be easily integrated either into an external receiver or the implantable neurostimulator, was constructed and proven to receive the RF signal from the implant when in proximity (20 cm) to it. The small size of the sensor provides continuous pH monitoring with minimal obstruction of the esophagus. The sensor could be used in routine clinical practice for 24/96 h esophageal pH monitoring without the need to insert a nasal catheter. The "zero-power" nature of the receiver also enables the use of the sensor for automatic in-vivo calibration of miniature lower esophageal sphincter neurostimulation devices. An active sensor-based control enables the development of advanced algorithms to minimize the used energy to achieve a desirable clinical outcome. One of the examples of such an algorithm would be a closed-loop system for on-demand neurostimulation therapy of gastroesophageal reflux disease (GERD).


Assuntos
Monitoramento do pH Esofágico , Refluxo Gastroesofágico , Animais , Refluxo Gastroesofágico/diagnóstico , Concentração de Íons de Hidrogênio , Próteses e Implantes , Suínos
17.
Cancer Genomics Proteomics ; 18(3): 221-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33893076

RESUMO

BACKGROUND/AIM: Pancreatic ductal adenocarcinoma (PDAC) still represents one of the most aggressive cancers. Understanding of the epithelial-mesenchymal crosstalk as a crucial part of the tumor microenvironment should pave the way for therapies to improve patient survival rates. Well-established cell lines present a useful and reproducible model to study PDAC biology. However, the tumor-stromal interactions between cancer cells and cancer-associated fibroblasts (CAFs) are still poorly understood. MATERIALS AND METHODS: We studied interactions between four PDAC cell lines (Panc-1, CAPAN-2, MIAPaCa-2, and PaTu-8902) and conditioned media derived from primary cultures of normal fibroblasts/PDAC-derived CAFs (PANFs). RESULTS: When the tested PDAC cell lines were stimulated by PANF-derived conditioned media, the most aggressive behavior was acquired by the Panc-1 cell line (increased number and size of colonies, remaining expression of vimentin and keratin 8 as well as increase of epithelial-to-mesenchymal polarization markers), whereas PaTu-8902 cells were rather inhibited. Of note, administration of the conditioned media to MIAPaCa-2 cells resulted in an inverse effect on the size and number of colonies, whereas CAPAN-2 cells were rather stimulated. To explain the heterogeneous pattern of the observed PDAC crosstalk at the in vitro level, we further compared the phenotype of primary cultures of cells derived from ascitic fluid with that of the tested PDAC cell lines, analyzed tumor samples of PDAC patients, and performed gene expression profiling of PANFs. Immuno-cyto/histo-chemical analysis found specific phenotype differences within the group of examined patients and tested PDAC cell lines, whereas the genomic approach in PANFs found the key molecules (IL6, IL8, MFGE8 and periostin) that may contribute to the cancer aggressive behavior. CONCLUSION: The desmoplastic patient-specific regulation of cancer cells by CAFs (also demonstrated by the heterogeneous response of PDAC cell lines to fibroblasts) precludes simple targeting and development of an effective treatment strategy and rather requires establishment of an individualized tumor-specific treatment protocol.


Assuntos
Fibroblastos Associados a Câncer/patologia , Carcinoma Ductal Pancreático/patologia , Fibroblastos/patologia , Neoplasias Pancreáticas/patologia , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Fibroblastos/metabolismo , Humanos , Neoplasias Pancreáticas/metabolismo , Microambiente Tumoral
18.
Vasc Endovascular Surg ; 55(5): 519-523, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33583359

RESUMO

A large tumorous mass completely surrounding and compressing the coeliac trunk was identified on computed tomography in a young woman with a six-month history of progressive abdominal pain. The tumor was excised along with the coeliac trunk and the proximal parts of its branches. The hepatic artery was reconstructed with an aorto-hepatic autogenous bypass. Postoperatively the patient had neurogenic diarrhea, which subsided on medical treatment. Seven months after surgery the patient is in a good state of health and living a normal life.


Assuntos
Artéria Celíaca/cirurgia , Ganglioneuroma/cirurgia , Artéria Hepática/cirurgia , Veia Safena/transplante , Adulto , Artéria Celíaca/diagnóstico por imagem , Artéria Celíaca/patologia , Dissecação , Feminino , Ganglioneuroma/diagnóstico por imagem , Ganglioneuroma/patologia , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/patologia , Humanos , Ligadura , Resultado do Tratamento
19.
In Vivo ; 35(1): 31-39, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33402447

RESUMO

Pancreatic ductal adenocarcinoma represents a disease with increasing incidence. Its prognosis is the worst among all malignancies despite the aggressive combined multimodal treatment across all stages. In metastatic disease, median survival is approximatelly one year. The mainstay of treatment is chemotherapy (neo/adjuvant, palliative) and in selected subgroups of patients even radiotherapy. Nevertheless, nowadays there are very few prognostic and/or predictive biomarkers available that can be used to identify and better stratify patients based on risk to tailored treatment. Potentially, promising areas of research are circulating tumor cells and circulating tumor DNA, which can be easily obtained from peripheral blood - so called liquid biopsy. They may serve as a tool to assess response to applied treatment, and to detect the emergence of treatment-resistant clones or early disease relapse. Moreover, their study may allow identification of potentially tumor-specific alterations, which may serve as target structures for targeted (tailored) therapy. Alternatively, different prognostic indexes/scores calculated by analysis of selected parameters of blood and/or biochemistry can be used to better stratify patients based on risk and better predict prognosis. The aim of this mini-review is to provide a basic overview of the current state of the art in this area and its potential significance for clinical practice.


Assuntos
Carcinoma Ductal Pancreático , DNA Tumoral Circulante , Células Neoplásicas Circulantes , Neoplasias Pancreáticas , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , DNA Tumoral Circulante/genética , Humanos , Recidiva Local de Neoplasia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Prognóstico
20.
Cas Lek Cesk ; 159(6): 203-209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33297694

RESUMO

Surgical resection remains the cornerstone for the curative treatment of oncological disease. In a situation when a tumour encases a critical arterial or venous structure, long term oncological control may be achieved only through careful preoperative planning within a multidisciplinary team incorporating oncological and vascular specialists. The present review addresses the principles in planning oncovascular surgery, describes the oncovascular procedure in pancreatic, liver, renal and endometriosis cancer as well as vascular involvement in retroperitoneal soft sarcoma and sarcoma in lower extremity. In conclusion, the present review highlights that major vessel involvement of a tumour mass should not necessarily be considered as a barrier to en bloc resection and hence curative oncosurgery procedure.


Assuntos
Neoplasias Retroperitoneais , Sarcoma , Feminino , Humanos , Procedimentos Cirúrgicos Vasculares
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