Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
2.
J Funct Biomater ; 14(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36662072

RESUMO

The production of nanoparticles for biomedical applications (namely with antimicrobial and anticancer properties) has been significantly hampered using traditional physicochemical approaches, which often produce nanostructures with poor biocompatibility properties requiring post-synthesis functionalization to implement features that such biomedical applications require. As an alternative, green nanotechnology and the synthesis of environmentally friendly nanomaterials have been gaining attention over the last few decades, using living organisms or biomolecules derived from them, as the main raw materials to produce cost-effective, environmentally friendly, and ready-to-be-used nanomaterials. In this article and building upon previous knowledge, we have designed and implemented the synthesis of selenium and tellurium nanoparticles using extracts from fresh jalapeño and habanero peppers. After characterization, in this study, the nanoparticles were tested for both their antimicrobial and anticancer features against isolates of antibiotic-resistant bacterial strains and skin cancer cell lines, respectively. The nanosystems produced nanoparticles via a fast, eco-friendly, and cost-effective method showing different antimicrobial profiles between elements. While selenium nanoparticles lacked an antimicrobial effect at the concentrations tested, those made of tellurium produced a significant antibacterial effect even at the lowest concentration tested. These effects were correlated when the nanoparticles were tested for their cytocompatibility and anticancer properties. While selenium nanoparticles were biocompatible and had a dose-dependent anticancer effect, tellurium-based nanoparticles lacked such biocompatibility while exerting a powerful anti-cancer effect. Further, this study demonstrated a suitable mechanism of action for killing bacteria and cancer cells involving reactive oxygen species (ROS) generation. In summary, this study introduces a new green nanomedicine synthesis approach to create novel selenium and tellurium nanoparticles with attractive properties for numerous biomedical applications.

3.
Skeletal Radiol ; 50(12): 2395-2404, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33982130

RESUMO

BACKGROUND: Management of pectoralis major (PM) injuries is largely determined by the anatomic location of the injury, with tendon avulsions from the humerus requiring surgery while myotendinous (MT) injuries are typically managed non-operatively. Because physical examination cannot reliably make this distinction, MRI is often used for staging. However, correct classification can also be difficult with MRI where there is extensive soft tissue edema and distorted anatomy. OBJECTIVE: To determine the diagnostic performance of primary and secondary MRI signs of PM injury for distinguishing tendon avulsions from MT injuries in a selected sample of patients that underwent surgical repair using a practical interpretation algorithm. METHODS: In this retrospective study, 3 blinded observers independently assessed the MRI findings of 17 patients with PM injury (including 12 acute injuries, 4 chronic, and 1 of uncertain age) where subsequent surgery documented tendon avulsion (11) and MT injuries (6) by applying the primary MRI criteria of absent tendon at the humerus, retracted tendon stump, epicenter of edema, and the secondary finding of soft tissue edema contacting the anterior humeral cortex. Operative findings were used as the reference standard. Sensitivity, specificity, and positive and negative predictive value were recorded for each finding. RESULTS: The primary MRI finding of lack of a visible tendon at the insertion (sensitivity 82-100%, specificity 100%) and the secondary finding of edema contacting the anterior humeral cortex (sensitivity 64-91%, specificity 67-100%) were both useful for the distinction of tendon avulsion from MT injury, particularly in acute injuries. The presence of a retracted tendon stump and the epicenter of edema were not reliable findings. The use of a decision tree including the secondary finding of humeral edema increased the sensitivity and specificity for 2 of the 3 observers. CONCLUSION: MRI assessment of PM injury focused on the humeral insertion of the PM tendon allows accurate distinction of tendon avulsion from MT injury. CLINICAL IMPACT: This study describes a practical approach to classifying PM injuries with MRI to distinguish injuries that require surgery from those that can potentially be managed conservatively.


Assuntos
Músculos Peitorais , Traumatismos dos Tendões , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Traumatismos dos Tendões/diagnóstico por imagem , Tendões
4.
Nanomaterials (Basel) ; 11(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670538

RESUMO

Cancer and antimicrobial resistance to antibiotics are two of the most worrying healthcare concerns that humanity is facing nowadays. Some of the most promising solutions for these healthcare problems may come from nanomedicine. While the traditional synthesis of nanomaterials is often accompanied by drawbacks such as high cost or the production of toxic by-products, green nanotechnology has been presented as a suitable solution to overcome such challenges. In this work, an approach for the synthesis of tellurium (Te) nanostructures in aqueous media has been developed using aloe vera (AV) extracts as a unique reducing and capping agent. Te-based nanoparticles (AV-TeNPs), with sizes between 20 and 60 nm, were characterized in terms of physicochemical properties and tested for potential biomedical applications. A significant decay in bacterial growth after 24 h was achieved for both Methicillin-resistant Staphylococcus aureus and multidrug-resistant Escherichia coli at a relative low concentration of 5 µg/mL, while there was no cytotoxicity towards human dermal fibroblasts after 3 days of treatment. AV-TeNPs also showed anticancer properties up to 72 h within a range of concentrations between 5 and 100 µg/mL. Consequently, here, we present a novel and green approach to produce Te-based nanostructures with potential biomedical applications, especially for antibacterial and anticancer applications.

5.
Nat Biomed Eng ; 4(3): 272-285, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32165735

RESUMO

For oral, oropharyngeal and oesophageal cancer, the early detection of tumours and of residual tumour after surgery are prognostic factors of recurrence rates and patient survival. Here, we report the validation, in animal models and a human, of the use of a previously described fluorescently labelled small-molecule inhibitor of the DNA repair enzyme poly(ADP-ribose) polymerase 1 (PARP1) for the detection of cancers of the oral cavity, pharynx and oesophagus. We show that the fluorescent contrast agent can be used to quantify the expression levels of PARP1 and to detect oral, oropharyngeal and oesophageal tumours in mice, pigs and fresh human biospecimens when delivered topically or intravenously. The fluorescent PARP1 inhibitor can also detect oral carcinoma in a patient when applied as a mouthwash, and discriminate between fresh biopsied samples of the oral tumour and the surgical resection margin with more than 95% sensitivity and specificity. The PARP1 inhibitor could serve as the basis of a rapid and sensitive assay for the early detection and for the surgical-margin assessment of epithelial cancers of the upper intestinal tract.


Assuntos
Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Orofaríngeas/diagnóstico por imagem , Poli(ADP-Ribose) Polimerase-1/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/isolamento & purificação , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Biomarcadores Tumorais/isolamento & purificação , Biomarcadores Tumorais/metabolismo , Modelos Animais de Doenças , Neoplasias Esofágicas/patologia , Feminino , Xenoenxertos/diagnóstico por imagem , Humanos , Masculino , Camundongos , Neoplasias Orofaríngeas/patologia , Suínos
6.
Expert Opin Drug Deliv ; 17(3): 341-356, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32064959

RESUMO

Introduction: Current treatments for osteogenic disorders are often successful, however they are not free of drawbacks, such as toxicity or side effects. Nanotechnology offers a platform for drug delivery in the treatment of bone disorders, which can overcome such limitations. Nevertheless, traditional synthesis of nanomaterials presents environmental and health concerns due to its production of toxic by-products, the need for extreme and harsh raw materials, and their lack of biocompatibility over time.Areas covered: This review article contains an overview of the current status of treating osteogenic disorders employing green nanotechnological approaches, showing some of the latest advances in the application of green nanomaterials, as drug delivery carriers, for the effective treatment of osteogenic disorders.Expert opinion: Green nanotechnology, as a potential solution, is understood as the use of living organisms, biomolecules and environmentally friendly processes for the production of nanomaterials. Nanomaterials derived from bacterial cultures or biomolecules isolated from living organisms, such as carbohydrates, proteins, and nucleic acids, have been proven to be effective composites. These nanomaterials introduce enhancements in the treatment and prevention of osteogenic disorders, compared to physiochemically-synthesized nanostructures, specifically in terms of their improved cell attachment and proliferation, as well as their ability to prevent bacterial adhesion.


Assuntos
Doenças Ósseas/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanotecnologia , Portadores de Fármacos/química , Humanos , Nanoestruturas
7.
Diagn Interv Radiol ; 25(5): 353-359, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31358490

RESUMO

PURPOSE: Percutaneous cementoplasty is a minimally invasive treatment modality for painful osteoporotic and pathologic sacral and supra-acetabular iliac fractures. This study compares the use of low-dose CT guidance with CT/CT fluoroscopy in sacral and supra-acetabular cementoplasty. METHODS: A retrospective review of patients who had undergone sacral or supra-acetabular cementoplasty was performed with patients grouped by use of CT/CT fluoroscopy or low-dose CT guidance during the procedure. Parameters evaluated included type of fracture, laterality of lesions, pain scores, pain medication use, imaging parameters, procedure time, dose-length product, effective dose, cement volume, and complications. RESULTS: There were 17 patients identified who underwent cementoplasty utilizing dual CT/CT fluoroscopy, while 13 patients had their procedures performed with low-dose CT. There was a statistically significant decrease in radiation dose in the low-dose CT group (1481 mGy•cm) compared with the CT/CT fluoroscopy group (2809 mGy•cm) (P = 0.013). There was a significant decrease in procedure time with low-dose CT for bilateral lesions (P = 0.016). There was no significant difference between groups in complication rate (P = 0.999). Clinically nonsignificant cement extravasation occurred in two patients (10%) in the CT/CT fluoroscopy group and in one patient (8%) in the low-dose CT group (P = 0.999). There was a significant decrease in pain scores compared with baseline on the visual analogue scale in both groups at 1 week (low-dose CT P = 0.002, CT/CT fluoroscopy P = 0.008) and 1 month postprocedure (low-dose CT P = 0.014, CT/CT fluoroscopy P = 0.004), but no difference between groups at 1 day (P = 0.196), 1 week (P = 0.368), or 1 month (P = 0.514). CONCLUSION: Sacral and supra-acetabular cementoplasties can be performed safely and precisely using low-dose multiple-acquisition CT guidance while providing significant radiation dose reduction with no difference in extravasation rates, postprocedural pain reduction, and complications compared with CT/CT fluoroscopy.


Assuntos
Cementoplastia/métodos , Radiografia Intervencionista/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adulto , Idoso , Feminino , Fluoroscopia/métodos , Humanos , Ílio/diagnóstico por imagem , Ílio/cirurgia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Doses de Radiação , Estudos Retrospectivos , Sacro/diagnóstico por imagem , Sacro/cirurgia , Resultado do Tratamento
8.
Pract Radiat Oncol ; 7(5): 325-331, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28377141

RESUMO

PURPOSE: 11C-acetate positron emission tomography (PET) imaging allows for the detection of occult metastatic disease that may otherwise go undetected with standard imaging for prostate cancer (PCa). The aim of this study was to evaluate lymph node coverage of the standard Radiation Therapy Oncology Group (RTOG) whole pelvic radiation therapy (WPRT) field in patients found to have node-positive PCa determined by 11C-acetate PET imaging. METHODS AND MATERIALS: A retrospective analysis was conducted on 125 PCa patients who underwent 11C-acetate PET scans at our institution between 2007 and 2014. Patients were included if they had evidence of nodal disease without distant metastatic cancer. Individual lymph nodes were characterized by location, size, and relationship to the RTOG WPRT field. RESULTS: A total of 55 11C-acetate PET scans (from 54 men) met criteria for inclusion in the study. Median age at diagnosis was 61 years. Median prostate-specific antigen values at diagnosis and at the time of the scan were 9.2 and 8.1 ng/mL, respectively. A total of 159 positive lymph nodes were identified, 78% of which were smaller than 1 cm. The most frequently involved lymphatic regions were the external iliacs (38.4%), para-aortics (19.5%), and common iliacs (16.3%). Additionally, 10.1% of positive nodes were identified as nodes of Cloquet. Of the positive nodes, 51.6% were determined to reside outside of the radiation field and, of those, the most common sites were para-aortic (36.9%), proximal common iliac (17.8%), distal external iliac (17.8%), and nodes of Cloquet (17.8%). CONCLUSIONS: Based on 11C-acetate PET imaging in patients with PCa, the standard RTOG WPRT field may miss more than one-half of all positive lymph nodes. Clinicians should be aware of the potential for insufficient nodal coverage when using the standard RTOG WPRT field in patients with node-positive PCa. 11C-acetate PET imaging may be useful in defining target volumes for these patients.


Assuntos
Linfonodos/patologia , Pelve/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Acetatos , Adulto , Idoso , Carbono , Radioisótopos de Carbono , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Pelve/efeitos da radiação , Guias de Prática Clínica como Assunto , Antígeno Prostático Específico/análise , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/normas , Estudos Retrospectivos
9.
Hepat Oncol ; 4(3): 75-81, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30191056

RESUMO

AIM: Compare radioembolization (Y90) and chemoembolization (CE) for the treatment of unresectable intrahepatic cholangiocarcinoma (UICC). MATERIALS & METHODS: Institutional Review Board-approved, retrospective search was performed. Forty patients with UICC were treated with either Y90 (n = 25, 39 treatments) or CE (n = 15, 35 treatments). Comparative analysis was performed using Student's t and fisher-exact tests. Multivariable-logistic regression was also performed. RESULTS: Median ages were 60 and 64 years for CE and Y90 groups, respectively (p = 0.798). Patient variables including age, Eastern Cooperative Oncology Group score, tumor burden, extra-hepatic disease, prior chemotherapy and prior surgery were similar between groups. Adverse events were similar in both groups (CE 20%, Y90 26%; p > 0.9). Overall response rate (CE 6%, Y90 4%; p > 0.9) and disease control rate (CE 46%, Y90 48%; p > 0.9) were statistically similar. Multilogistic regression did not identify any variables that correlated with disease control rate, including Eastern Cooperative Oncology Group score and tumor burden. CONCLUSION: Our observation shows that CE and Y90 display similar toxicity and disease control in the treatment of UICC.

10.
J Neurointerv Surg ; 8(6): 568-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26002302

RESUMO

BACKGROUND: The increasing utilization of balloon guide catheters (BGCs) in thrombectomy therapy for ischemic stroke has led to concerns about large-bore sheaths causing vascular groin complications.Objective To retrospectively assess the impact of large large-bore sheaths and vascular closure devices on groin complication rates at a comprehensive stroke center over a 10-year period. METHODS: Radiological and clinical records of patients with acute ischemic stroke who underwent mechanical endovascular therapy with an 8Fr or larger sheaths were reviewed. A groin complication was defined as the formation of a groin hematoma, retroperitoneal hematoma, femoral artery pseudoaneurysm, or the need for surgical repair. Information collected included size of sheath, type of hemostatic device, and anticoagulation status of the patient. Blood bank records were also analyzed to identify patients who may have had an undocumented blood transfusion for a groin hematoma. RESULTS: A total of 472 patients with acute ischemic stroke who underwent mechanical thrombectomy with a sheath and BGC sized 8Fr or larger were identified. 260 patients (55.1%) had tissue Plasminogen Activator (tPA) administered as part of stroke treatment. Vascular closure devices were used in 97.9% of cases (n=462). Two patients were identified who had definite groin complications and a further two were included as having possible complications. There was a very low rate of clinically significant groin complications (0.4-0.8%) associated with the use of large-bore sheaths. CONCLUSIONS: These findings suggest that concerns for groin complications should not preclude the use of BGCs and large-bore sheaths in mechanical thrombectomy for acute ischemic stroke.


Assuntos
Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Artéria Femoral/cirurgia , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Idoso , Falso Aneurisma/etiologia , Falso Aneurisma/terapia , Embolectomia com Balão , Catéteres/efeitos adversos , Procedimentos Endovasculares/instrumentação , Feminino , Virilha/cirurgia , Hematoma/etiologia , Hematoma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombectomia/instrumentação , Dispositivos de Oclusão Vascular/efeitos adversos
11.
J Nucl Med Technol ; 44(1): 46-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26111708

RESUMO

The inguinal lymph nodes are an unusual site of metastases for prostate adenocarcinoma. We present a case in which a 61-y-old man with biochemically recurrent prostate cancer underwent attenuation-corrected (11)C-acetate PET/CT, which demonstrated multiple foci of increased activity in the left inguinal, left iliac chain, and right inguinal regions. The attenuation-corrected CT portion of the scan also showed anterior wall thickening of the rectum. The imaging findings were suggestive of metastatic involvement of the rectum below the dentate line with subsequent spread to the inguinal lymph nodes.


Assuntos
Acetatos , Carbono , Processamento de Imagem Assistida por Computador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade
12.
BMJ Case Rep ; 20152015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26199297

RESUMO

A 49-year-old woman was admitted with Hunt and Hess grade 1 subarachnoid haemorrhage. A cerebral aneurysm of the intracranial left vertebral artery (VA) distal to the left posterior inferior cerebellar artery (PICA) was found and treated using parent vessel occlusion with coils. The PICA was preserved. Angiography at three time points during her hospitalisation showed a normal right VA. Eight months later, angiography demonstrated a new 14 mm right VA dissecting aneurysm with 90% outflow stenosis and recurrence of the left VA aneurysm distal to the coils. A Marksman microcatheter would not traverse the stenosis despite the use of two intraluminal wires. Following Gateway balloon (1.5 mm × 9 mm) angioplasty, the Marksman passed easily. The pipeline embolisation device (PED) was successfully deployed across the aneurysm and 11 coils placed through a trapped microcatheter. The patient was discharged home 2 days later. Eighteen-month follow-up has revealed complete resolution of both aneurysms.


Assuntos
Angioplastia/instrumentação , Angioplastia/métodos , Embolização Terapêutica/métodos , Aneurisma Intracraniano/complicações , Dissecação da Artéria Vertebral/terapia , Artéria Vertebral/patologia , Angiografia Cerebral/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/terapia , Resultado do Tratamento , Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/complicações , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/etiologia
13.
BMJ Case Rep ; 20132013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23345490

RESUMO

Ischaemic colitis is a rare side effect of antipsychotics, especially phenothiazines and atypical antipsychotics. The colitis may be precipitated secondary to the anticholinergic effects of such medication rather than a direct cytotoxic effect of the drugs themselves. A 32-year-old man with a history of schizophrenia was admitted to the hospital with a history of diffuse abdominal pain and vomiting. His bloods showed leucocytosis. Sigmoidoscopy demonstrated rectal sparing acute colitis, confirmed on biopsy findings. A CT scan also showed similar findings. After careful drug review, it was decided that clozapine was the cause of colitis and promptly stopped. The patient was managed conservatively on intravenous fluids and antibiotics and made a full recovery. Any patient starting antipsychotics should be counselled on their anticholinergic side effects. Drugs should always be considered as a cause of ischaemic colitis; although an uncommon complication of antipsychotics, it can have a potentially fatal outcome.


Assuntos
Clozapina/efeitos adversos , Colite Isquêmica/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Adulto , Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Biópsia , Clozapina/uso terapêutico , Colite Isquêmica/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Sigmoidoscopia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...