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1.
Vasc Endovascular Surg ; : 15385744241284876, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264598

RESUMO

BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive treatment for lower limb varicose veins. Studies indicate that RFA results in immediate occlusion of 90%-100% of treated long saphenous veins. Evidence suggests that post-operative scans rarely alter patient management or outcomes. OBJECTIVE: The aim of this study was to assess the potential necessity of routine postoperative scanning in the treatment of varicose veins. METHOD: Retrospective data were collected for the patients who had RFA under a single consultant from November 2015 to June 2018. Descriptive statistics were calculated to summarize patient demographics, procedural details, and outcome measures. RESULTS: A total of 124 patients underwent radiofrequency ablation (RFA). Most of the patients (n = 114, 92%) demonstrated complete ablation, indicating a high success rate for the procedure. CONCLUSION: This study suggested that routine postoperative scanning should be discontinued as this did not alter patient management in over 99% of cases. The resources currently used for postoperative scans could be redirected towards other critical areas.

2.
Wetlands (Wilmington) ; 43(8): 105, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38037553

RESUMO

Wetlands cover a small portion of the world, but have disproportionate influence on global carbon (C) sequestration, carbon dioxide and methane emissions, and aquatic C fluxes. However, the underlying biogeochemical processes that affect wetland C pools and fluxes are complex and dynamic, making measurements of wetland C challenging. Over decades of research, many observational, experimental, and analytical approaches have been developed to understand and quantify pools and fluxes of wetland C. Sampling approaches range in their representation of wetland C from short to long timeframes and local to landscape spatial scales. This review summarizes common and cutting-edge methodological approaches for quantifying wetland C pools and fluxes. We first define each of the major C pools and fluxes and provide rationale for their importance to wetland C dynamics. For each approach, we clarify what component of wetland C is measured and its spatial and temporal representativeness and constraints. We describe practical considerations for each approach, such as where and when an approach is typically used, who can conduct the measurements (expertise, training requirements), and how approaches are conducted, including considerations on equipment complexity and costs. Finally, we review key covariates and ancillary measurements that enhance the interpretation of findings and facilitate model development. The protocols that we describe to measure soil, water, vegetation, and gases are also relevant for related disciplines such as ecology. Improved quality and consistency of data collection and reporting across studies will help reduce global uncertainties and develop management strategies to use wetlands as nature-based climate solutions. Supplementary Information: The online version contains supplementary material available at 10.1007/s13157-023-01722-2.

3.
Eur Rev Med Pharmacol Sci ; 27(8): 3699-3713, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140319

RESUMO

OBJECTIVE: Kidney stones are a common complication of hyperoxaluria. The aim of this study is to investigate the protective and preventive effects of Ulva lactuca aqueous extract, ulvan polysaccharides and atorvastatin on ethylene glycol-induced hyperoxaluria. MATERIALS AND METHODS: Male Wistar rats between 110 and 145 g in weight were used in the study, Ulva lactuca aqueous extract and polysaccharides were prepared. The male albino rats were supplemented with 0.75 percent ethylene glycol (v/v) in their drinking water for six weeks to induce hyperoxaluria. Ulvan infusions (100 mg/kg body weight), ulvan polysaccharides (100 mg/kg body weight), and atorvastatin (two milligrams/kg body weight) to treat hyperoxaluric rats for four weeks (every other day) were used. Weight loss, serum creatinine, serum urea, serum uric acid, serum oxalate, kidney oxalate, kidney lipid peroxidation, and kidney DNA fragmentation and kidney histopathological studies were done. RESULTS: Weight loss, rise of serum creatinine, serum urea, serum uric acid, serum oxalate, kidney oxalate, kidney lipid peroxidation, and kidney DNA fragmentation were all shown to be prevented by the addition of atorvastatin, polysaccharides, or aqueous extract, respectively. Catalase (CAT) activity, glutathione peroxidase (GPX) activity, glutathione-S-transferase (GST) activity, and histopathological perturbations were all significantly reduced by the medicines that were studied. CONCLUSIONS: Hyperoxaluria caused by ethylene glycol may be prevented by a combination of Ulva lactuca aqueous extract, ulvan polysaccharides, and atorvastatin. A reduction in renal oxidative stress and an improvement of the antioxidant defense system may be responsible for these protective benefits. However, Ulva lactuca infusion and ulvan polysaccharides need to be studied further in humans, in order to determine their efficacy and safety.


Assuntos
Hiperoxalúria , Ulva , Masculino , Humanos , Animais , Ratos , Atorvastatina/farmacologia , Ácido Úrico , Etilenoglicol/toxicidade , Creatinina , Ratos Wistar , Rim/patologia , Polissacarídeos/farmacologia , Antioxidantes/efeitos adversos , Oxalatos/efeitos adversos , Peso Corporal , Redução de Peso , Ureia
4.
Med Image Comput Comput Assist Interv ; 14228: 249-259, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38515783

RESUMO

In cochlear implant (CI) procedures, an electrode array is surgically inserted into the cochlea. The electrodes are used to stimulate the auditory nerve and restore hearing sensation for the recipient. If the array folds inside the cochlea during the insertion procedure, it can lead to trauma, damage to the residual hearing, and poor hearing restoration. Intraoperative detection of such a case can allow a surgeon to perform reimplantation. However, this intraoperative detection requires experience and electrophysiological tests sometimes fail to detect an array folding. Due to the low incidence of array folding, we generated a dataset of CT images with folded synthetic electrode arrays with realistic metal artifact. The dataset was used to train a multitask custom 3D-UNet model for array fold detection. We tested the trained model on real post-operative CTs (7 with folded arrays and 200 without). Our model could correctly classify all the fold-over cases while misclassifying only 3 non fold-over cases. Therefore, the model is a promising option for array fold detection.

5.
Clin Epigenetics ; 14(1): 98, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915507

RESUMO

Histone 3 lysine 27 (H3K27) demethylation constitutes an important epigenetic mechanism of gene activation. It is mediated by the Jumonji C domain-containing lysine demethylases KDM6A and KDM6B, both of which have been implicated in a wide myriad of diseases, including blood and solid tumours, autoimmune and inflammatory disorders, and infectious diseases. Here, we review and summarise the pre-clinical evidence, both in vitro and in vivo, in support of the therapeutic potential of inhibiting H3K27-targeting demethylases, with a focus on the small-molecule inhibitor GSK-J4. In malignancies, KDM6A/B inhibition possesses the ability to inhibit proliferation, induce apoptosis, promote differentiation, and heighten sensitivity to currently employed chemotherapeutics. KDM6A/B inhibition also comprises a potent anti-inflammatory approach in inflammatory and autoimmune disorders associated with inappropriately exuberant inflammatory and autoimmune responses, restoring immunological homeostasis to inflamed tissues. With respect to infectious diseases, KDM6A/B inhibition can suppress the growth of infectious pathogens and attenuate the immunopathology precipitated by these pathogens. The pre-clinical in vitro and in vivo data, summarised in this review, suggest that inhibiting H3K27 demethylases holds immense therapeutic potential in many diseases.


Assuntos
Histonas , Neoplasias , Metilação de DNA , Epigênese Genética , Histona Desmetilases/genética , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética
6.
In Vivo ; 36(4): 1551-1569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35738604

RESUMO

BACKGROUND/AIM: Papillary thyroid cancer (PTC) is the most common endocrine malignancy with a rising incidence. There is a need for a non-invasive preoperative test to enable better patient counselling. The aim of this systematic review was to investigate the potential role of circulating microRNAs (miRNAs) in the diagnosis and prognosis of PTC. MATERIALS AND METHODS: A systematic literature search was performed using MEDLINE, Cochrane, and Scopus databases (last search date was December 1, 2021). Studies investigating the expression of miRNAs in the serum or plasma of patients with PTC were deemed eligible for inclusion. RESULTS: Among the 1,533 screened studies, 39 studies met the inclusion criteria. In total, 108 miRNAs candidates were identified in the serum, plasma, or exosomes of patients suffering from PTC. Furthermore, association of circulating miRNAs with thyroid cancer-specific clinicopathological features, such as tumor size (13 miRNAs), location (3 miRNAs), extrathyroidal extension (9 miRNAs), pre- vs. postoperative period (31 miRNAs), lymph node metastasis (17 miRNAs), TNM stage (9 miRNAs), BRAF V600E mutation (6 miRNAs), serum thyroglobulin levels (2 miRNAs), 131I avid metastases (13 miRNAs), and tumor recurrence (2 miRNAs) was also depicted in this study. CONCLUSION: MiRNAs provide a potentially promising role in the diagnosis and prognosis of PTC. There is a correlation between miRNA expression profiles and specific clinicopathological features of PTC. However, to enable their use in clinical practice, further clinical studies are required to validate the predictive value and utility of miRNAs as biomarkers.


Assuntos
Carcinoma Papilar , Carcinoma , MicroRNA Circulante , MicroRNAs , Neoplasias da Glândula Tireoide , Carcinoma/patologia , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , MicroRNA Circulante/genética , Humanos , MicroRNAs/genética , Mutação , Recidiva Local de Neoplasia/genética , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
7.
Cancer Med ; 11(15): 2957-2968, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35343093

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the second cause of cancer death worldwide. The role of circulating microvesicles as a screening tool is a novel, yet effective approach that warrants prioritised research. METHODS: In a two-gate diagnostic accuracy study, 35 patients with benign colorectal polyps (BCRP) (n = 16) and colorectal cancer (CRC) (n = 19) were compared to 17 age-matched healthy controls. Total annexin-V positive microvesicles and sub-populations positive for selected biomarkers relevant to bowel neoplasm were evaluated in patients' plasma using flow cytometry. Statistical methods including factor analysis utilising two component factors were performed to obtain optimal diagnostic accuracy of microvesicles in identifying patients with colorectal neoplasms. RESULTS: Total plasma microvesicles, and sub-populations positive for CD31, CD42a, CD31+/CD42a-, EPHB2, ICAM and LGR5 (component factor-1) were able to identify patients with BCRP and CRC with a receiver operator curve (AUC) accuracy of a 100% (95% CI: 100%-100%) and 95% (95% CI: 88%-100%), respectively. To identify patients with BCRP, a cut-off point value of component factor-1761 microvesicles/µl demonstrated a 100% sensitivity, specificity and negative predictive value (NPV) and a 93% positive predictive value (PPV). To identify patients with CRC, a cut-off value of component factor-1 3 439 microvesicles/µl demonstrated a 100% sensitivity, specificity and NPV and a 65% PPV. CEA+ microvesicles sub-population were significantly (p < 0.02) higher in CRC in comparison to BCRP. CONCLUSIONS: Microvesicles as biomarkers for the early and accurate detection of CRC is a simple and effective tool that yields a potential breakthrough in clinical management.


Assuntos
Neoplasias Colorretais , Proteínas de Neoplasias , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Biomarcadores , Biomarcadores Tumorais , Neoplasias Colorretais/diagnóstico , Humanos , Programas de Rastreamento
8.
Beilstein J Nanotechnol ; 11: 829-842, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551208

RESUMO

We realized integrated photonics multi-waveguide devices for optical trapping and Raman spectroscopy of particles in a fluid. In these devices, multiple beams directed towards the device center lead to a local field enhancement around this center and thus counteract the effect of light concentration near the facets, which is a disadvantage of dual-waveguide traps. Thus, a trapping region is created around the center, where a single particle of a size in a wide range can be trapped and studied spectroscopically, free from the influence of surfaces. We report the design (including simulations), fabrication and performance demonstration for multi-waveguide devices, using our Si3N4 waveguiding platform as the basis. The designed ridge waveguides, optimized for trapping and Raman spectroscopy, emit narrow beams. Multiple waveguides arranged around the central microbath result from fanning out of a single input waveguide using Y-splitters. A second waveguiding layer is implemented for detection of light scattered by the trapped particle. For reliable filling of the device with sample fluid, microfluidic considerations lead to side channels of the microbath, to exploit capillary forces. The interference of the multiple beams produces an array of hot spots around the bath center, each forming a local trap. This property is clearly confirmed in the experiments and is registered in videos. We demonstrate the performance of a 2-waveguide and a 16-waveguide device, using 1 and 3 µm polystyrene beads. Study of the confined Brownian motion of the trapped beads yields experimental values of the normalized trap stiffness for the in-plane directions. The stiffness values for the 16-waveguide device are comparable to those of tightly focused Gaussian beam traps and are confirmed by our own simulations. The Raman spectra of the beads (in this work measured via an objective) show clear peaks that are characteristic of polystyrene. In the low-wavenumber range, the spectra have a background that most likely originates from the Si3N4 waveguides.

9.
J Med Imaging (Bellingham) ; 7(3): 031504, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32509912

RESUMO

Purpose: Cochlear implants (CIs) use an array of electrodes surgically threaded into the cochlea to restore hearing sensation. Techniques for predicting the insertion depth of the array into the cochlea could guide surgeons toward more optimal placement of the array to reduce trauma and preserve the residual hearing. In addition to the electrode array geometry, the base insertion depth (BID) and the cochlear size could impact the overall array insertion depth. Approach: We investigated using these measurements to develop a linear regression model that can make preoperative or intraoperative predictions of the insertion depth of lateral wall CI electrodes. Computed tomography (CT) images of 86 CI recipients were analyzed. Using previously developed automated algorithms, the relative electrode position inside the cochlea was measured from the CT images. Results: A linear regression model is proposed for insertion depth prediction based on cochlea size, array geometry, and BID. The model is able to accurately predict angular insertion depths with a standard deviation of 41 deg and absolute deviation error of 32 deg. Conclusions: Surgeons may use this model for patient-customized selection of electrode array and/or to plan a BID for a given array that minimizes the likelihood of causing trauma to regions of the cochlea where residual hearing exists.

11.
J Surg Educ ; 73(4): 567-74, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26970717

RESUMO

INTRODUCTION: This study investigates the efficiency of teaching basic surgical skills to foundation-year doctors and medical students by using local resources. METHODS: A course comprising 4 workshops, once a week, of 3 hours duration per session was delivered using local education center facilities and using the local faculty of consultants and surgical trainees. Teaching methods include practical skill stations supplemented with short didactic lectures and group discussion. Precourse and postcourse assessments were completed by candidates and analyzed to measure outcomes of the course both subjectively and objectively. RESULTS: A total number of 20 participants completed the course. On completion of the course, (1) participants' theoretical knowledge improved significantly (p < 0.0001), as measured by multiple-choice questions, and scores improved by 35% (mean 44%, standard deviation = 16%) before the course compared to (mean = 79%, standard deviation = 13) after the course; (2) the level of confidence in knowledge and skills was measured by a questionnaire on a scale of 1 to 5, and there was a significant (p < 0.0001) improvement on postcourse assessment (mean difference = 1.5, 95% CI: 0.7-2.4); and (3) practical skills such as suture position, knot tying, and wound apposition significantly improved after the course, χ(2) (2) = 16, p < 0.001; χ(2) (2) = 18, p < 0.001; and χ(2) (2) = 22, p < 0.0001, respectively. CONCLUSION: Effective delivery of basic surgical skills to foundation-year doctors by using local resources can be achieved at low cost.


Assuntos
Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Educação de Graduação em Medicina/métodos , Cirurgia Geral/educação , Adulto , Currículo , Avaliação Educacional , Feminino , Humanos , Londres , Masculino , Modelos Educacionais , Desenvolvimento de Programas , Inquéritos e Questionários
12.
Environ Sci Pollut Res Int ; 20(9): 6646-57, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23625052

RESUMO

This study examined the relationship between the abundance of bacterial denitrifiers in groundwater at four sites, differing with respect to overlaying land management and peizometer depth. Groundwater was sourced from 36 multilevel piezometers, which were installed to target different groundwater zones: (1) subsoil, (2) subsoil to bedrock interface, and (3) bedrock. The gene copy concentrations (GCCs), as gene copies per liter, for bacterial 16S rRNA genes and the denitrifying functional genes, nirK, nirS, and nosZ, were determined using quantitative polymerase chain reaction assays. The results were related to gaseous nitrogen emissions and to the physicochemical properties of the four sites. Overall, nirK and nirS abundance appeared to show no significant correlation to N2O production (P = 0.9989; P = 0.3188); and no significant correlation was observed between nosZ and excess N2 concentrations (P = 0.0793). In the majority of piezometers investigated, the variation of nirK and nirS gene copy concentrations was considered significant (P < 0.0001). Dissolved organic carbon (DOC) decreased with aquifer depth and ranged from 1.0-4.0 mg l(-1), 0.9-2.4 mg l(-1), and 0.8-2.4 mg l(-1) within piezometers located in the subsoil, subsoil/bedrock interface, and bedrock depths, respectively. The availability of increasing DOC and the depth of the water table were positively correlated with increasing nir and nosZ GCCs (P = 0.0012). A significant temporal correlation was noted between nirS and piezometer depth (P < 0.001). Interestingly, the nirK, nirS, and nosZ GCCs varied between piezometer depths within specific sites, while GCCs remained relatively constant from site to site, thus indicating no direct impact of agricultural land management strategies investigated on denitrifier abundance.


Assuntos
Agricultura , Bactérias/metabolismo , Genes Bacterianos , Água Subterrânea/microbiologia , Microbiologia da Água , Bactérias/classificação , Bactérias/genética , Irlanda , Nitrificação
13.
Cancer Res ; 66(20): 10064-72, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17047070

RESUMO

Despite the initial efficacy of androgen deprivation therapy, most patients with advanced prostate cancer eventually progress to hormone-refractory prostate cancer, for which there is no curative therapy. Previous studies from our laboratory and others have shown the antiproliferative and proapoptotic effects of 3,3'-diindolylmethane (DIM) in prostate cancer cells. However, the molecular mechanism of action of DIM has not been investigated in androgen receptor (AR)-positive hormone-responsive and -nonresponsive prostate cancer cells. Therefore, we investigated the effects of B-DIM, a formulated DIM with greater bioavailability, on AR, Akt, and nuclear factor kappaB (NF-kappaB) signaling in hormone-sensitive LNCaP (AR+) and hormone-insensitive C4-2B (AR+) prostate cancer cells. We found that B-DIM significantly inhibited cell proliferation and induced apoptosis in both cell lines. By Akt gene transfection, reverse transcription-PCR, Western blot analysis, and electrophoretic mobility shift assay, we found a potential crosstalk between Akt, NF-kappaB, and AR. Importantly, B-DIM significantly inhibited Akt activation, NF-kappaB DNA binding activity, AR phosphorylation, and the expressions of AR and prostate-specific antigen, suggesting that B-DIM could interrupt the crosstalk. Confocal studies revealed that B-DIM inhibited AR nuclear translocation, leading to the down-regulation of AR target genes. Moreover, B-DIM significantly inhibited C4-2B cell growth in a severe combined immunodeficiency-human model of experimental prostate cancer bone metastasis. These results suggest that B-DIM-induced cell proliferation inhibition and apoptosis induction are partly mediated through the down-regulation of AR, Akt, and NF-kappaB signaling. These observations provide a rationale for devising novel therapeutic approaches for the treatment of hormone-sensitive, but more importantly, hormone-refractory prostate cancer by using B-DIM alone or in combination with other therapeutics.


Assuntos
Antagonistas de Receptores de Andrógenos , Indóis/farmacologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Masculino , NF-kappa B/metabolismo , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Antígeno Prostático Específico/antagonistas & inibidores , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/biossíntese , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos
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