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1.
Hum Brain Mapp ; 44(17): 5729-5748, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37787573

RESUMO

Despite the known benefits of data-driven approaches, the lack of approaches for identifying functional neuroimaging patterns that capture both individual variations and inter-subject correspondence limits the clinical utility of rsfMRI and its application to single-subject analyses. Here, using rsfMRI data from over 100k individuals across private and public datasets, we identify replicable multi-spatial-scale canonical intrinsic connectivity network (ICN) templates via the use of multi-model-order independent component analysis (ICA). We also study the feasibility of estimating subject-specific ICNs via spatially constrained ICA. The results show that the subject-level ICN estimations vary as a function of the ICN itself, the data length, and the spatial resolution. In general, large-scale ICNs require less data to achieve specific levels of (within- and between-subject) spatial similarity with their templates. Importantly, increasing data length can reduce an ICN's subject-level specificity, suggesting longer scans may not always be desirable. We also find a positive linear relationship between data length and spatial smoothness (possibly due to averaging over intrinsic dynamics), suggesting studies examining optimized data length should consider spatial smoothness. Finally, consistency in spatial similarity between ICNs estimated using the full data and subsets across different data lengths suggests lower within-subject spatial similarity in shorter data is not wholly defined by lower reliability in ICN estimates, but may be an indication of meaningful brain dynamics which average out as data length increases.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Rede Nervosa/diagnóstico por imagem , Encéfalo/diagnóstico por imagem
2.
Nanotechnology ; 32(47)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-33618335

RESUMO

In this work we adapt rare-earth-ion-doped NaYF4nanoparticles coated with a silicon oxide shell (NaYF4:20%Yb,0.2%Tm@SiO2) for biological and medical applications (for example, imaging of cancer cells and therapy at the nano level). The wide upconversion emission range under 980 nm excitation allows one to use the nanoparticles for cancer cell (4T1) photodynamic therapy (PDT) without a photosensitizer. The reactive oxygen species (ROS) are generated by Tm/Yb ion upconversion emission (blue and UV light). Thein vitroPDT was tested on 4T1 cells incubated with NaYF4:20%Yb,0.2%Tm@SiO2nanoparticles and irradiated with NIR light. After 24 h, cell viability decreased to below 10%, demonstrating very good treatment efficiency. High modification susceptibility of the SiO2shell allows for attachment of biological molecules (specific antibodies). In this work we attached the anti-human IgG antibody to silane-PEG-NHS-modified NaYF4:20%Yb,0.2%Tm@SiO2nanoparticles and a specifically marked membrane model by bio-conjugation. Thus, it was possible to perform a selective search (a high-quality optical method with a very low-level organic background) and eventually damage the targeted cancer cells. The study focuses on therapeutic properties of NaYF4:20%Yb,0.2%Tm@SiO2nanoparticles and demonstrates, upon biological functionalization, their potential for targeted therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia , Túlio/química , Túlio/farmacocinética , Túlio/farmacologia , Itérbio/química , Itérbio/farmacocinética , Itérbio/farmacologia , Ítrio/química , Ítrio/farmacocinética , Ítrio/farmacologia
3.
J Physiol Pharmacol ; 72(5)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-35158330

RESUMO

Diabetes-induced vasculopathies are linked to inflammation mediated by mutually inhibitory nuclear factor-kappaB (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2). NF-κB is activated by superoxide (O2 ˙-)- producing nicotinamide adenine dinucleotide phosphate (NADPH) oxidase homologues, including NADPH oxidase 2 (Nox2), and vice versa, with NF-κB inducing Nox2. Nrf2 is activated by H2O2-producing Nox4 and nitric oxide (NO), but also induces NADPH oxidase 4 (Nox4) and endothelial nitric oxide synthase (eNOS). The NF-κB/Nox2 system is upregulated and Nrf2/Nox4/eNOS is downregulated in diabetes. We hypothesized that this vascular-deleterious imbalance results from the reduced vascular NO signaling, and so may be prevented by exercise training and sodium nitrite (interventions known to replenish vascular NO), and be reproduced by nitric oxide synthase (NOS) inhibition. Streptozotocin diabetic rats were examined on days 4, 10, 49 and 84 of diabetes. From day 4 onwards, plasma nitrite was reduced while NF-κB nuclear accumulation in the heart and kidneys gradually increased, while Nrf2 decreased. In parallel, the cardiac expression of signatures of the NF-κB (inducible nitric oxide synthase (iNOS), vascular cell adhesion molecule-1 (VCAM-1), NADPH oxidase 2 Nox2) increased and of the Nrf2 (Nox4, eNOS, heme-oxygenase-1 (HO-1)) decreased. Exercise training and dietary nitrite prevented this phenotype in the 49-day diabetes model. 7-day treatment of non-diabetic rats with NOS inhibitor of Nω-nitro-L-arginine methyl ester (L-NAME) recapitulated the NF-κB/Nox2 and Nrf2/Nox4/eNOS imbalance, as seen in diabetic rats. Nitrite failed to prevent the changes induced by L-NAME. The coherence of changes in NF-κB, Nox2, Nrf2, Nox4 and eNOS under the various settings of this study aimed at modifying the vascular NO leads us to propose that NF-κB/Nox2 and Nrf2/Nox4/eNOS are two crosstalking functional subsystems of one larger regulatory network, with NOS-derived NO ensuring the balance between these subsystems, and thus preventing vascular oxidative stress, endothelial dysfunction and inflammation.


Assuntos
Diabetes Mellitus Experimental , Óxido Nítrico Sintase Tipo III , Animais , Arginina/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Peróxido de Hidrogênio , NADPH Oxidase 2 , NADPH Oxidase 4 , Fator 2 Relacionado a NF-E2 , NF-kappa B/metabolismo , Óxido Nítrico , Óxido Nítrico Sintase Tipo III/metabolismo , Nitritos , Nitroglicerina , Estresse Oxidativo , Ratos
4.
Rozhl Chir ; 99(12): 521-528, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33445922

RESUMO

The article describes the development of oncosurgery in the Czech Republic since the beginning of the century, as well as other perspectives regarding this specialty. The development of surgical treatment of solid malignant tumours in the Czech Republic was evaluated according to the National Cancer Register database and compared to the neighbouring countries, and the educational system of surgeons in oncosurgery was assessed. Although surgery plays a key role in cancer therapy, starting from the beginning of this millennium it has been pushed aside as a service specialty for other disciplines in oncology. In 2002, these changes were supported by the activities of the newly founded Division of Oncosurgery under the Czech Society for Oncology, which became part of the Czech Surgical Society in 2016. An official educational programme of surgeons in oncology was successfully implemented and since 2011, a specialization examination in oncosurgery has been introduced, organized by the subdepartment of oncosurgery of the Institute of Postgraduate Medical Education (IPVZ), Prague. To date, this examination has been completed by 112 physicians and approximately the same number is currently registered in the educational programme. Currently, 34 centres are accredited for education in oncosurgery. The establishment of Complex Oncology Centres based on an initiative of the Czech Society for Oncology of 2006 only addressed pharmaceutical and radiation oncology. Despite progress in oncosurgery, more clearly defined conditions for this specialty are needed. Conclusion: The education of surgeons in oncosurgery should be continued. It is necessary to expand the number of centres with accreditation for oncosurgery and develop a concept for oncosurgery in the Czech Republic which would be associated with rational concentration of this treatment in connection with organization and provision of continuous urgent and acute surgical care in the Czech Republic, including control mechanisms to ensure its quality. This proposal should be discussed by the Czech Surgical Society in order to further enhance the quality of oncosurgery in the Czech Republic.


Assuntos
Neoplasias , República Tcheca/epidemiologia , Humanos , Neoplasias/cirurgia , Especialização
5.
J Physiol Pharmacol ; 70(1)2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31172974

RESUMO

Within the mammalian reproductive system sirtuin 1 and 6 (SIRT1, SIRT6) are considered to contribute to steroid hormone signaling and control of reproductive physiology. Therefore, the specific question is whether and how a commonly used dicarboximide fungicide with antiandrogenic activity, vinclozolin (Vnz) alters SIRT1 and SIRT6 expression and whether both investigated sirtuins positively affect survival of the follicles after vinclozolin exposure. Immunocytochemistry and immunohistochemistry were performed to localize SIRT1 and SIRT6 expression in cultured granulosa cells (GCs; 48 hours) and whole ovarian follicles (24 hours) after treatment with two androgens, testosterone (T; 10-7 M) and dihydrotestosterone (DHT; 10-7 M), and an antiandrogen, Vnz (1.4 x 10-5 M), separately and in combinations. Granulosal and follicular mRNA and protein expression of both sirtuins was also investigated by real-time PCR and Western blot. In addition, their concentration and activity was studied by immunoenzymatic and fluorescence assays. Our observations: (1) demonstrate the presence of both investigated sirtuins in ovarian cells, (2) show their potential involvement in the control of follicular atresia because of increased SIRT1/SIRT6 expression and SIRT1 activity after exposure to Vnz, (3) represent the first data on the interrelationships between sirtuins and androgens in porcine ovarian cells. Based on these findings and our previous results we can conclude, that SIRT1 and SIRT6 do not exert the protective effects in ovarian follicles after vinclozolin exposure. These novel data on the role of SIRT1/SIRT6 in porcine ovarian follicles shows that in the presence of the investigated fungicide, sirtuins are upregulated, which can induce apoptosis of follicular cells. Furthermore the androgen receptor sensitivity to ligands, especially environmental ones (for example: vinclozolin) might be directly linked with the mechanism of action of both investigated sirtuins in the porcine ovary, which requires further investigation.


Assuntos
Antagonistas de Androgênios/farmacologia , Ovário/efeitos dos fármacos , Oxazóis/farmacologia , Sirtuínas/metabolismo , Androgênios/farmacologia , Animais , Di-Hidrotestosterona/farmacologia , Feminino , Ovário/metabolismo , Sirtuínas/genética , Suínos , Testosterona/farmacologia
6.
Rozhl Chir ; 97(8): 384-393, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30441992

RESUMO

INTRODUCTION: Gastric resections due to carcinoma belong to the most demanding procedures in visceral surgery. This is due to the requirements for the extent of resection and lymphadenectomy, coupled with the need for functional reconstruction of the digestive tract. The procedure is associated with 18-46% morbidity, which delays administration of adjuvant therapy and worsens oncological results. Identification of risk factors for potential complications may play an important role in the indication and perioperative care. The aim of our study is to (i) evaluate the morbidity a mortality of a patient group with post-gastrectomy complications and to (ii) identify associated risk factors. METHOD: This retrospective analysis comprises patients treated in 2005-2016. Gastric resection was performed in 266 adenocarcinoma patients, 172 men and 94 women (median age 66 years). Early post-operative complications following gastrectomy were observed within 60 days. Complications and their severity were evaluated according to the extended form of the Accordion Severity Grading System. Selected demographic risk factors, operative factors and malignancy-related factors were analyzed. Multivariate regression (orthogonal projections to latent structure) was used for statistical processing. RESULTS: Overall morbidity and mortality was 34.6% and 3.4%. Serious complications occurred in 51 operated patients (19.2%). 24 patients had two or three complications (9%). The most common grades of severity were grade 2 in 31 patients (11.7%) and grade 4 in 20 patients (10.9%). The duration of hospital stay correlated with the severity of the complication. Most common surgical complications were: intra-abdominal abscess (16.4%, 17 cases), wound complications (5.3%, 14 cases), pancreatitis (4.9%, 13 cases), anastomotic leakage (3.4%, 9 cases), postoperative ileus (3.4%, 9 cases). Respiratory and cardiac complications were the most common non-surgical complications (8.6%, 23 cases and 3.8%, 20 cases, respectively). In the derived statistical model, BMI, the presence of more comorbidities, lesser surgical experience, the length of hospital stay and hospitalization at ICU were identified as risk factors associated with the grade of complication, morbidity, presence of serious complication and multiple complications. CONCLUSION: Gastrectomy plays a fundamental role in the curative treatment of gastric carcinoma; it is, however, associated with substantial morbi-dity and mortality. The best management of complications is their prevention. Preoperatively, the greatest attention should be paid to patients with several comorbidities and higher BMI. Resections should be performed by experienced surgeons. During resection, consideration should be given to the extent of resection and lymphadenectomy. In the postoperative period, the length of hospital stay, especially at ICU, should be reduced to minimum. Analyses of these risk factors may decrease the incidence of complications. Key words: gastric cancer - gastrectomy - risk factors - complications.


Assuntos
Gastrectomia , Neoplasias Gástricas , Idoso , Feminino , Gastrectomia/efeitos adversos , Humanos , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/cirurgia
7.
Rozhl Chir ; 97(7): 320-327, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30442013

RESUMO

INTRODUCTION: Minimally invasive methods for esophagectomy have been introduced to reduce postoperative complications. This paper compares open transhiatal esophagectomy and minimally invasive hybrid esophagectomy. Both methods have different extents of lymphadenectomy, transhiatal esophagectomy being considered less radical. METHOD: A single-centre retrospective study comprised 39 patients subjected to transhiatal esophagectomy and 25 patients subjected to hybrid esophagectomy combining thoracoscopy with laparotomy and cervical anastomosis. All patients were operated for middle and distal third carcinoma of the esophagus, including cardia (Siewert II), in the period of 2006-2016 at the Surgery department of Nový Jicín hospital. The data of both groups, in particular the incidence of early postoperative complications and the number of dissected lymph nodes, were statistically compared. Complications are reported according to the International Consensus on Standardization of Data Collection for Complications Associated with Esophagectomy. RESULTS: The duration of operation was significantly longer in the group that underwent hybrid resections (345 vs. 240 min, p<0.001). The number of dissected lymph nodes was comparable in both groups (15 vs. 16, p=0.072). Postoperative pulmonary complications were lower for hybrid operations (16% vs. 30.8%, p=0.243). The most common complication of transhiatal esophagectomy was pleural effusion requiring drainage, which occurred in 7 patients. The most common pulmonary complication of hybrid procedures was respiratory failure, which occurred in 3 patients. Anastomotic leak occurred in 5 patients after transhiatal esophagectomy and in one after thoracoscopic resection (12.8% vs. 4%, p=0.391). 30-day and 90-day mortality was nonsignificantly lower for hybrid resections (0% vs. 5.1%, p=0.516 and 4% vs. 10.3%, p=0.64). Following transhiatal esophagectomy, two patients died as a result of respiratory complications, one died from necrosis of the gastric tube and one from acute myocardial infarction. In the hybrid group, one patient died from respiratory failure. Hybrid resection exhibited lower morbidity (36% vs. 59%, p=0.123). The number of overall complications, irrespective of their severity according to the Clavien-Dindo classification, was statistically in favor of hybrid resection (11 vs. 30, p=0.015). CONCLUSION: In our study, we found that thoracoscopic hybrid resection was a feasible and well-executable method, with a statistically lower incidence of postoperative complications. Thoracoscopy allows lymphadenectomy to be performed to sufficient extent. The large number and various combinations of esophagectomy techniques make it difficult to evaluate and compare the outcomes of individual methods. Preference for a specific resection technique within a given surgical department remains an important factor as clear recommendations for esophageal resections do not yet exist. However, the use of minimally invasive techniques in esophageal resections is gradually becoming a standard. Key words: minimally invasive esophagectomy - thoracoscopy - postoperative complications - lymphadenectomy.


Assuntos
Neoplasias Esofágicas , Esofagectomia , Laparoscopia , Neoplasias Esofágicas/cirurgia , Humanos , Complicações Pós-Operatórias , Estudos Retrospectivos , Toracoscopia
8.
Rozhl Chir ; 97(7): 328-334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30442014

RESUMO

INTRODUCTION: Chylothorax after esophageal resection is an uncommon but serious complication with a reported incidence of 1-10%. It occurs after the injury of the thoracic duct or its tributaries. Chylothorax may cause an overall loss of several liters per day and may lead to dehydration, malnutrition and immunosuppression. Therapeutic approach has not been standardized. Prophylactic ligation of the thoracic duct during primary resection has been introduced to decrease the overall incidence of chylothorax. Its oncological benefit is unknown. METHOD: A retrospective single-center study of patients who underwent transthoracic esophagectomy from 2008-2016 for esophageal carcinoma at the Department of Surgery, Hospital Nový Jicín. 58 patients underwent transthoracic esophagectomy (Ivor-Lewis and McKeown). Prophylactic ligation of the thoracic duct was performed in 31 patients (53%). The incidence of chylothorax and the amount of harvested lymph nodes was analysed in the group with thoracic duct ligation (A PTDL 31 patients) and in the non-ligation group (B 27 patients). RESULTS: Overall incidence of chylothorax after transthoracic esophagectomy was 3.4%. Chylothorax occurred in two men (type 3B) in the prophylactic group (6.5%) and it was not observed in the non-ligation group. Statistically significant difference was not confirmed (p=0,494). Chylous leak was successfully treated thoracoscopically and by thoracotomy with repeat ligation of the thoracic duct. Non-significantly more lymph nodes were harvested in the prophylactic group (18 A PTDL vs. 15 B, p=1). CONCLUSION: Prophylactic ligation of the thoracic duct in our study did not reduce the incidence of chylothorax. Redo thoracotomy and redo thoracoscopy for chylothorax is feasible. In patients with high-output and long lasting leaks the indication for redo surgery should be early. Key words: chylothorax - esophageal resection - prophylactic thoracic duct ligation.


Assuntos
Quilotórax , Neoplasias Esofágicas , Esofagectomia , Quilotórax/etiologia , Quilotórax/prevenção & controle , Neoplasias Esofágicas/cirurgia , Esofagectomia/efeitos adversos , Humanos , Ligadura , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Ducto Torácico
9.
Rozhl Chir ; 97(7): 309-319, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30442012

RESUMO

INTRODUCTION: Analysis of the epidemiology and treatment of cancer of the stomach (CS) and gastro-esophageal junction (GEJ) in the Czech Republic (CR). METHOD: Analysis from the National Cancer Registry (NCR) of the CR examined data up to the year 2013. RESULTS: In CS and GEJ, the incidence is 14.3, mortality is 10.5 and prevalence is 51.1 per 100,000 population. The Karlovy Vary, Olomouc and Moravian-Silesian regions had the highest incidences. The median age at diagnosis is 69 years for men and 72 years for women. Location in the stomach prevails in 85% of the patients, cancer of the gastric cardia occurring in 15%. In men, this ratio is 81 to 19%, in women 90 to 10%. The disease is usually diagnosed late; in 2013, 36% of CS and 32% of GEJ tumors were stage I and II. 53% of CS and 56% of tumors of the GEJ were diagnosed as stage III and IV, and in 11% and 12%, the stage was not determined. In the years 2009-2013 (1,580 patients with CS and GEJ), only 22% were treated surgically, surgery and oncological treatment was given to 21.3%, only non-surgical treatment was received by 15.7% and 41% of patients received no oncological treatment. Overall five-year survival in patients treated between 2010 and 2013 was 32%. At stage I it was 69%, at stage II 41%, at stage III 23% and at stage IV it was 6%. Five-year survival rates according to disease stage and type of treatment given and median of survival were analysed on 8,348 patients with CS and GEJ between 2004 and 2013. Surgery only was performed in 4,116 patients, surgery and radiotherapy was administered to 113 patients, surgery and chemotherapy to 1,855 patients, and 1,125 patients received chemotherapy alone. In 98% of the treated patients, chemotherapy and/or radiotherapy was administered adjuvantly after the surgery. Primary operations were performed at a total of 175 surgical centers, only 22 of them performing more than 10 operations annually. The median of survival differed depending on the number of operations performed: at enters performing more than 20 operations, the median was 24.8 months (m); at enters performing 10-19 operations, the median was 18.2 m; at centers performing 6-9 operations the median was 18.1 m; and at centers performing less than 6 operations, the median was 13.1 m. CONCLUSION: Early diagnosis is key for five-year survival. Treatment is based on surgery; greatest improvement is seen when surgery is combined with chemoradiotherapy, which is usually administered adjuvantly in the CR. At stage I in CS +9.5%, GEJ cancer +26.5%, at stage II in CS +14.7%, GEJ cancer +16.4% and at stage III in CS +13.3%, GEJ cancer +2.6%. Palliative chemo and/or radiotherapy does not prolong five-year survival and must be selected on an individual basis with regard to the expected benefit for the patient. Facilities performing a greater number of surgical procedures have better long-term results. Key words: malignant esophageal tumors - epidemiology - treatment - results.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Adenocarcinoma/cirurgia , Idoso , República Tcheca , Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica , Feminino , Humanos , Masculino , Estadiamento de Neoplasias , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida
10.
J Biol Regul Homeost Agents ; 32(2 Suppl. 1): 1-10, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29460512

RESUMO

Multiple recession defects in the dentition of the patients are routinely encountered in clinical practice and as such present a challenge for clinicians. Periodontal plastic surgical procedures aim to restore both esthetics as function in periodontal tissues. The objective of this study was to evaluate and compare the clinical efficacy of using a tunnel technique with a collagen matrix to cover multiple recessions in the maxilla or mandible. Fourteen patients were enrolled in the study. Patients in the maxilla-group and mandible-group were treated with xenogeneic collagen matrix using the tunnel technique. Clinical recordings were obtained at baseline and after 3 and 6 months. The percentage of average recession coverage (ARC), the percentage rate of patients with complete coverage of all recessions (CRC-1) and the percentage rate of complete coverage of recession defects (CRC-2) were evaluated after 3 and 6 months after the surgery. Statistically significant differences were observed in every parameter except probing depth between the baseline values compared to the values 3 and 6 months after the procedure in both groups. The mean ARC 6 months after the procedure was 96.8% in the maxilla and 81.3% in the mandible. At 6 months after the procedure, a complete root coverage was obtained in 2 out of 9 patients and 31 out of 39 recessions (79%) in the maxilla and 0 out of 5 patients and 10 out of 20 recessions (50%) in the mandible. A collagen matrix combined with the tunnel technique led to a satisfactory ARC, CRC- 2 and resulted in an unsatisfactory CRC-1.


Assuntos
Colágeno , Retração Gengival/cirurgia , Mandíbula , Maxila , Procedimentos Cirúrgicos Bucais , Tecido Conjuntivo , Humanos , Fatores de Tempo , Resultado do Tratamento
11.
Cell Biochem Biophys ; 75(3-4): 443-454, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29098642

RESUMO

The mammalian retina contains a high level of polyunsaturated fatty acids, including docosahexaenoic acid (22:6) (DHA), which are highly susceptible to oxidation. It has been shown that one of the products of DHA oxidation-carboxyethylpyrrole (CEP), generated in situ, causes modifications of retinal proteins and induces inflammation response in the outer retina. These contributing factors may play a role in the development of age-related macular degeneration (AMD). It is also possible that some of the lipid oxidation products are photoreactive, and upon irradiation with blue light may generate reactive oxygen species. Therefore, in this work we analysed oxidation-induced changes in photoreactivity of lipids extracted from bovine neural retinas. Lipid composition of bovine neural retinas closely resembles that of human retinas making the bovine tissue a convenient model for studying the photoreactivity and potential phototoxicity of oxidized human retinal lipids. Lipid composition of bovine neural retinas Folch' extracts (BRex) was determined by gas chromatography (GC) and liquid chromatography coupled to an electrospray ionization source-mass spectrometer (LC-ESI-MS) analysis. Liposomes prepared from BRex, equilibrated with air, were oxidized in the dark at 37 °C for up to 400 h. The photoreactivity of BRex at different stages of oxidation was studied by EPR-oximetry and EPR-spin trapping. Photogeneration of singlet oxygen (1O2, 1Δg) by BRex was measured using time-resolved detection of the characteristic phosphorescence at 1270 nm. To establish contribution of lipid components to the analysed photoreactivity of Folch' extract of bovine retinas, a mixture of selected synthetic lipids in percent by weight (w/w %) ratio resembling that of the BRex has been also studied. Folch's extraction of bovine neural retinas was very susceptible to oxidation despite the presence of powerful endogenous antioxidants such as α-tocopherol and zeaxanthin. Non-oxidized and oxidized BRex photogenerated singlet oxygen with moderate quantum yield. Blue-light induced generation of superoxide anion by Folch' extract of bovine neural retinas strongly depended on the oxidation time. The observed photoreactivity of the studied extract gradually increased during its in vitro oxidation.


Assuntos
Lipídeos/química , Retina/metabolismo , Animais , Bovinos , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância de Spin Eletrônica , Luz , Lipídeos/análise , Lipossomos/química , Oxirredução/efeitos da radiação , Oxigênio/análise , Teoria Quântica , Oxigênio Singlete/análise , Espectrometria de Massas por Ionização por Electrospray , Marcadores de Spin , Zeaxantinas/química , alfa-Tocoferol/análise
12.
Transl Psychiatry ; 7(5): e1133, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28509905

RESUMO

Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) together affect >10% of the children in the United States, but considerable behavioral overlaps between the two disorders can often complicate differential diagnosis. Currently, there is no screening test designed to differentiate between the two disorders, and with waiting times from initial suspicion to diagnosis upwards of a year, methods to quickly and accurately assess risk for these and other developmental disorders are desperately needed. In a previous study, we found that four machine-learning algorithms were able to accurately (area under the curve (AUC)>0.96) distinguish ASD from ADHD using only a small subset of items from the Social Responsiveness Scale (SRS). Here, we expand upon our prior work by including a novel crowdsourced data set of responses to our predefined top 15 SRS-derived questions from parents of children with ASD (n=248) or ADHD (n=174) to improve our model's capability to generalize to new, 'real-world' data. By mixing these novel survey data with our initial archival sample (n=3417) and performing repeated cross-validation with subsampling, we created a classification algorithm that performs with AUC=0.89±0.01 using only 15 questions.


Assuntos
Algoritmos , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Espectro Autista/diagnóstico , Transtorno Autístico/diagnóstico , Crowdsourcing/métodos , Aprendizado de Máquina/estatística & dados numéricos , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Transtorno Autístico/epidemiologia , Criança , Comportamento Infantil/psicologia , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Medição de Risco , Estados Unidos/epidemiologia
13.
Rozhl Chir ; 96(2): 92-97, 2017.
Artigo em Tcheco | MEDLINE | ID: mdl-28429954

RESUMO

In this report, the authors describe a rare case of complete sternal resection for a metachronous metastasis from renal carcinoma in a 59-year-old female patient 12 years after primary left nephrectomy. Due to the large extent of resection, a polyester double layer mesh with bone cement was used for chest wall reconstruction. The postoperative course was uneventful without any indication for adjuvant treatment. The patient has been followed up for 20 months without any signs of complications and recurrence of her malignancy.Key words: sternum resection bone metastases renal carcinoma.


Assuntos
Neoplasias Ósseas , Carcinoma de Células Renais , Neoplasias Renais , Procedimentos de Cirurgia Plástica , Neoplasias Ósseas/secundário , Neoplasias Ósseas/cirurgia , Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Esterno/cirurgia
14.
Transl Psychiatry ; 6: e732, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26859815

RESUMO

Although autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) continue to rise in prevalence, together affecting >10% of today's pediatric population, the methods of diagnosis remain subjective, cumbersome and time intensive. With gaps upward of a year between initial suspicion and diagnosis, valuable time where treatments and behavioral interventions could be applied is lost as these disorders remain undetected. Methods to quickly and accurately assess risk for these, and other, developmental disorders are necessary to streamline the process of diagnosis and provide families access to much-needed therapies sooner. Using forward feature selection, as well as undersampling and 10-fold cross-validation, we trained and tested six machine learning models on complete 65-item Social Responsiveness Scale score sheets from 2925 individuals with either ASD (n=2775) or ADHD (n=150). We found that five of the 65 behaviors measured by this screening tool were sufficient to distinguish ASD from ADHD with high accuracy (area under the curve=0.965). These results support the hypotheses that (1) machine learning can be used to discern between autism and ADHD with high accuracy and (2) this distinction can be made using a small number of commonly measured behaviors. Our findings show promise for use as an electronically administered, caregiver-directed resource for preliminary risk evaluation and/or pre-clinical screening and triage that could help to speed the diagnosis of these disorders.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno Autístico/diagnóstico , Comportamento Infantil , Aprendizado de Máquina , Criança , Diagnóstico Diferencial , Humanos
15.
Rozhl Chir ; 94(9): 362-6, 2015 Sep.
Artigo em Tcheco | MEDLINE | ID: mdl-26537100

RESUMO

INTRODUCTION: Gastric stump cancer accounts for 14% of all gastric carcinomas. Originally this term included patients who previously underwent surgery due to peptic ulcer disease but today gastric stump cancer also includes patients diagnosed some time after primary gastric resection due to gastric cancer. The incidence is increasing. Gastric stump cancer is associated with poor prognosis and its reported resecability is around 40%. METHODS: We retrospectively analyzed the data of 7 patients with a preoperatively histologically confirmed stump cancer who had been operated at the Department of Surgery at Nový Jicín Hospital during 2006-2014. RESULTS: We operated 5 men and 2 women with the median age of 70 years (5580). The primary surgical resection in all our patients was BII gastric resection due to peptic ulcer disease, and GSC had evolved within a median of 38 years (3246) after primary intervention. None of the patients had been regularly screened by endoscopy following primary surgery. We performed five curative resections (four total gastrectomies, one subtotal gastrectomy). Our resecability rate was 71%. In two cases, only explorative laparotomy was performed due to generalisation of the malignancy. Two patients from the resected group died after 30 and 34 months due to progression of their disease; the other three patients are still alive after 17, 19 and 88 months. CONCLUSION: Gastric stump cancer is a malignancy often diagnosed in its late stages. Regural endoscopic screening after primary gastric resection for benign disease can lead to diagnosis at an earlier stage, thereby improving the resection rate and overall survival. This also applies to long-term follow-up of patients with primary subtotal gastrectomy for cancer. Lymphatic metastasizing of the carcinoma can often be different due to the previous surgical intervention and altered anatomy. This must be taken into account during operations.


Assuntos
Carcinoma/cirurgia , Coto Gástrico/patologia , Coto Gástrico/cirurgia , Neoplasias Gástricas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Gastrectomia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Transl Psychiatry ; 5: e514, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25710120

RESUMO

Although the prevalence of autism spectrum disorder (ASD) has risen sharply in the last few years reaching 1 in 68, the average age of diagnosis in the United States remains close to 4--well past the developmental window when early intervention has the largest gains. This emphasizes the importance of developing accurate methods to detect risk faster than the current standards of care. In the present study, we used machine learning to evaluate one of the best and most widely used instruments for clinical assessment of ASD, the Autism Diagnostic Observation Schedule (ADOS) to test whether only a subset of behaviors can differentiate between children on and off the autism spectrum. ADOS relies on behavioral observation in a clinical setting and consists of four modules, with module 2 reserved for individuals with some vocabulary and module 3 for higher levels of cognitive functioning. We ran eight machine learning algorithms using stepwise backward feature selection on score sheets from modules 2 and 3 from 4540 individuals. We found that 9 of the 28 behaviors captured by items from module 2, and 12 of the 28 behaviors captured by module 3 are sufficient to detect ASD risk with 98.27% and 97.66% accuracy, respectively. A greater than 55% reduction in the number of behaviorals with negligible loss of accuracy across both modules suggests a role for computational and statistical methods to streamline ASD risk detection and screening. These results may help enable development of mobile and parent-directed methods for preliminary risk evaluation and/or clinical triage that reach a larger percentage of the population and help to lower the average age of detection and diagnosis.


Assuntos
Transtorno Autístico/diagnóstico , Transtorno Autístico/psicologia , Comportamento Infantil/psicologia , Diagnóstico por Computador/métodos , Aprendizado de Máquina/estatística & dados numéricos , Adolescente , Adulto , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Fatores de Risco , Adulto Jovem
18.
Transl Psychiatry ; 4: e424, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25116834

RESUMO

Current approaches for diagnosing autism have high diagnostic validity but are time consuming and can contribute to delays in arriving at an official diagnosis. In a pilot study, we used machine learning to derive a classifier that represented a 72% reduction in length from the gold-standard Autism Diagnostic Observation Schedule-Generic (ADOS-G), while retaining >97% statistical accuracy. The pilot study focused on a relatively small sample of children with and without autism. The present study sought to further test the accuracy of the classifier (termed the observation-based classifier (OBC)) on an independent sample of 2616 children scored using ADOS from five data repositories and including both spectrum (n=2333) and non-spectrum (n=283) individuals. We tested OBC outcomes against the outcomes provided by the original and current ADOS algorithms, the best estimate clinical diagnosis, and the comparison score severity metric associated with ADOS-2. The OBC was significantly correlated with the ADOS-G (r=-0.814) and ADOS-2 (r=-0.779) and exhibited >97% sensitivity and >77% specificity in comparison to both ADOS algorithm scores. The correspondence to the best estimate clinical diagnosis was also high (accuracy=96.8%), with sensitivity of 97.1% and specificity of 83.3%. The correlation between the OBC score and the comparison score was significant (r=-0.628), suggesting that the OBC provides both a classification as well as a measure of severity of the phenotype. These results further demonstrate the accuracy of the OBC and suggest that reductions in the process of detecting and monitoring autism are possible.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/classificação , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Diagnóstico por Computador , Algoritmos , Inteligência Artificial , Criança , Transtornos Globais do Desenvolvimento Infantil/genética , Pré-Escolar , Feminino , Heterogeneidade Genética , Humanos , Masculino , Determinação da Personalidade/estatística & dados numéricos , Fenótipo , Projetos Piloto , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Design de Software
20.
Rozhl Chir ; 93(6): 311-6, 2014 Jun.
Artigo em Tcheco | MEDLINE | ID: mdl-25047970

RESUMO

INTRODUCTION: Resection procedures for colorectal cancer are burdened with a relatively high number of complications. The aim of this study is to define risk factors associated with the development of postoperative complications based on retrospective data analysis. MATERIAL AND METHODS: From January 1 st 2007 to December 31st 2012, 1093 patients underwent surgery for colorectal cancer. Retrospectively, we selected a group of 406 patients who underwent planned, elective colon resection for colon cancer. Open surgery was performed in 158 patients (38.9%), laparoscopic resection in 248 patients (61.1%). Based on initial staging of the disease, there were 85 patients (20.9%) in stage I, 137 patients (33.8%) in stage II, 110 patients (27.1%) in stage III and 74 patients (18.2%) in stage IV. Postoperative complications were evaluated according to Clavien - Dindo classification. RESULTS: Grade I complications were observed in 34 patients (8.4%), grade II in 25 patients (6.2%), grade III in 43 patients (10.6%), grade IV in 7 patients (1.7%) and grade V in 8 patients (2.0%). The highest incidence of complications was observed in left colon resection procedures (41.1%), open resections (39.8%), procedures lasting longer than 301 minutes (50%), patients older than 81 years (41.6%) and in procedures performed by the youngest, less experienced surgeon (40.6%). CONCLUSION: Our results confirmed that the type and approach of surgical procedure, patients age and surgeons experience are risk factors associated with a higher incidence of postoperative complications. High-risk surgical patients should be operated on by experienced surgeon who regularly performs a high number of resection procedures.


Assuntos
Neoplasias do Colo/cirurgia , Complicações Pós-Operatórias , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Neoplasias do Colo/patologia , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos
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