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1.
J Radiol Prot ; 41(2)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271518

RESUMO

Ground robotic vehicles are often deployed to inspect areas where radioactive floor contamination is a prominent risk. However, the accuracy of detection could be adversely affected by enhanced radiation signal through self-contamination of the robot occurring over the course of the inspection. In this work, it was hypothesised that a six-legged robot could offer advantages over the more conventional ground robotic devices such as wheeled and tracked rovers. To investigate this, experimental contamination testing and computational Monte Carlo simulation techniques (GEANT4) were employed to understand how radioactive contamination pick-up on three different robotic vehicles would affect their detection accuracy. Two robotic vehicles were selected for comparison with the hexapod robot based on their type of locomotion; a wheeled rover and a tracked rover. With the aid of a non-toxic fluorescent tracer dust, the contamination received by the all three vehicles when traversing a contaminated area was initially compared through physical inspection using high definition cameras. The parametric results from these tests where used in the computational study carried out in GEANT4. A cadmium zinc telluride detector was simulated at heights ranging from 10 to 50 cm above each contaminated vehicle, as if it were mounted on a plinth. Assuming a uniform activity of 60 Bq cm-2on all contaminated surfaces, the results suggested that due to the hexapod's small ground-contacting surface area and geometry, radiation detection rates using an uncollimated detector are likely to be overestimated by between only 0.07%-0.12%, compared with 3.95%-8.43% and 1.75%-14.53% for the wheeled and tracked robot alternatives, respectively.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Simulação por Computador , Método de Monte Carlo
3.
Horm Behav ; 123: 104644, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31785281

RESUMO

Testosterone is often considered a critical regulator of aggressive behaviour. There is castration/replacement evidence that testosterone indeed drives aggression in some species, but causal evidence in humans is generally lacking and/or-for the few studies that have pharmacologically manipulated testosterone concentrations-inconsistent. More often researchers have examined differences in baseline testosterone concentrations between groups known to differ in aggressiveness (e.g., violent vs non-violent criminals) or within a given sample using a correlational approach. Nevertheless, testosterone is not static but instead fluctuates in response to cues of challenge in the environment, and these challenge-induced fluctuations may more strongly regulate situation-specific aggressive behaviour. Here, we quantitatively summarize literature from all three approaches (baseline, change, and manipulation), providing the most comprehensive meta-analysis of these testosterone-aggression associations/effects in humans to date. Baseline testosterone shared a weak but significant association with aggression (r = 0.054, 95% CIs [0.028, 0.080]), an effect that was stronger and significant in men (r = 0.071, 95% CIs [0.041, 0.101]), but not women (r = 0.002, 95% CIs [-0.041, 0.044]). Changes in T were positively correlated with aggression (r = 0.108, 95% CIs [0.041, 0.174]), an effect that was also stronger and significant in men (r = 0.162, 95% CIs [0.076, 0.246]), but not women (r = 0.010, 95% CIs [-0.090, 0.109]). The causal effects of testosterone on human aggression were weaker yet, and not statistically significant (r = 0.046, 95% CIs [-0.015, 0.108]). We discuss the multiple moderators identified here (e.g., offender status of samples, sex) and elsewhere that may explain these generally weak effects. We also offer suggestions regarding methodology and sample sizes to best capture these associations in future work.


Assuntos
Agressão/efeitos dos fármacos , Agressão/fisiologia , Testosterona/farmacologia , Testosterona/fisiologia , Ensaios Clínicos como Assunto/estatística & dados numéricos , Correlação de Dados , Criminosos/estatística & dados numéricos , Feminino , Humanos , Masculino , Violência/psicologia , Violência/estatística & dados numéricos
4.
Curr Oncol ; 26(3): e341-e345, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31285678

RESUMO

Background: Isolated abdominal lymphadenopathy is frequently detected, but often challenging to diagnose. To obtain a tissue diagnosis, percutaneous biopsy (pb) or laparoscopic biopsy (lb) is often undertaken. The safety profiles and diagnostic accuracy of pb and lb within the abdomen are both poorly defined. Methods: In this retrospective analysis, we identified all patients who underwent lb or pb for isolated abdominal lymphadenopathy at our institute during 2008-2016. Results: Of 62 patients who underwent nodal biopsy for isolated abdominal lymphadenopathy, 33 underwent lb and 29 underwent pb. For the 33 patients who underwent lb, the procedure was diagnostic in 100% of cases; for the 29 who underwent pb, the procedure was diagnostic in 18 cases (62.1%). Both procedures were safe, with similar complication rates (6.0% for lb; 7.0% for pb). Conclusions: Our results establish that lb and pb are both safe and reliable in the setting of isolated abdominal lymphadenopathy. We also demonstrate that each procedure has situational advantages. A pb should be considered to be the upfront diagnostic modality, particularly when anatomic or disease factors favour its success. In situations in which it is felt that pb cannot safely access the lymphadenopathy or in disease states in which the yield of a core biopsy will be insufficient, lb should be strongly considered. Examples include extra-retroperitoneal lymphadenopathy and cases of suspected lymphoma.


Assuntos
Linfonodos/cirurgia , Linfadenopatia/diagnóstico , Abdome/cirurgia , Idoso , Biópsia , Feminino , Humanos , Laparoscopia , Linfadenopatia/cirurgia , Masculino , Pessoa de Meia-Idade
5.
J Perinatol ; 37(10): 1103-1107, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28682316

RESUMO

OBJECTIVE: To examine outcomes of neonates based on the mode and intensity of resuscitation received in the delivery room (DR). STUDY DESIGN: A retrospective study of 439 infants with birth weight ⩽1500 g receiving DR resuscitation at two hospital centers in Philadelphia, Pennsylvania. RESULTS: Of 439 infants, 22 (5%) received routine care, 188 (43%) received noninvasive positive pressure ventilation (PPV) and 229 (52%) received endotracheal tube (ETT) intubation in the DR. Adjusted odds for respiratory distress syndrome was associated with lower rates in infants requiring lower intensity of DR resuscitation (P<0.001). Noninvasive PPV vs ETT was associated with decreased odds of developing intraventricular hemorrhage and retinopathy of prematurity (P<0.05). Routine vs noninvasive PPV or ETT had decreased odds of developing bronchopulmonary dysplasia (P<0.05). CONCLUSION: Decreased intensity of DR resuscitation was associated with a decreased risk of specific morbidities.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/estatística & dados numéricos , Intubação Intratraqueal/estatística & dados numéricos , Ventilação não Invasiva/estatística & dados numéricos , Ressuscitação/métodos , Adulto , Estudos de Casos e Controles , Cesárea/estatística & dados numéricos , Salas de Parto , Feminino , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva/estatística & dados numéricos , Intubação Intratraqueal/efeitos adversos , Masculino , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Ressuscitação/efeitos adversos , Estudos Retrospectivos , Adulto Jovem
6.
Analyst ; 142(8): 1381-1386, 2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-28098273

RESUMO

Mid-infrared microscopy has become a key technique in the field of biomedical science and spectroscopy. This label-free, non-destructive technique permits the visualisation of a wide range of intrinsic biochemical markers in tissues, cells and biofluids by detection of the vibrational modes of the constituent molecules. Together, infrared microscopy and chemometrics is a widely accepted method that can distinguish healthy and diseased states with high accuracy. However, despite the exponential growth of the field and its research world-wide, several barriers currently exist for its full translation into the clinical sphere, namely sample throughput and data management. The advent and incorporation of quantum cascade lasers (QCLs) into infrared microscopes could help propel the field over these remaining hurdles. Such systems offer several advantages over their FT-IR counterparts, a simpler instrument architecture, improved photon flux, use of room temperature camera systems, and the flexibility of a tunable illumination source. In this current study we explore the use of a QCL infrared microscope to produce high definition, high throughput chemical images useful for the screening of biopsied colorectal tissue.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Lasers Semicondutores , Microscopia , Espectroscopia de Infravermelho com Transformada de Fourier , Humanos
7.
Analyst ; 142(8): 1179-1184, 2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-27858020

RESUMO

Mid-infrared microscopy is a non-destructive, quantitative and label-free spectroscopic imaging technique that, as a result of recent instrument advancements, is now at the point of enabling high-throughput automated biochemical screening of whole histology samples. Currently the mid-infrared field is undergoing a paradigm shift that has not been seen since the introduction of scanning Fourier Transform interferometric spectrometers. The latest mid-infrared microscopes are powered by tunable quantum cascade laser (QCL) sources which offer a number of advantages including measurement protocol flexibility, ease-of-use and a greatly enhanced data acquisition speed at high spectral and spatial resolution. In this study we use a wide-field QCL infrared microscope to develop and validate a fast four-frequency protocol for imaging fibrosis in unstained liver tissue. We compare our results to the gold standard Masson's trichrome histochemical staining protocol.


Assuntos
Lasers Semicondutores , Cirrose Hepática/diagnóstico por imagem , Microscopia , Humanos , Coloração e Rotulagem
8.
Clin. transl. oncol. (Print) ; 18(5): 533-536, mayo 2016. tab, graf
Artigo em Inglês | IBECS | ID: ibc-151188

RESUMO

Purpose: Survival rates among patients with lymphoma continue to improve. Strategies aimed at reducing potential treatment-related toxicity are increasingly prioritized. While radiological procedures play an important role, ionizing radiation exposure has been linked to an increased risk of malignancy, particularly among individuals whose cumulative radiation exposure exceeds a specific threshold (75 millisieverts). Methods: Within this retrospective study, the cumulative radiation exposure dose was quantified for 486 consecutive patients with lymphoma. Results: The median estimated total cumulative effective dose (CED) of ionizing radiation per subject was 69 mSv (42-118). However, younger patients (under 40 years) had a median CED of 89 mSv (55-124). Conclusion: This study highlights the considerable radiation exposure occurring among patients with lymphoma as a result of diagnostic imaging. To limit the risk of secondary carcinogenesis, consideration should be given to monitoring cumulative radiation exposure in individual patients as well as considering imaging modalities, which do not impart an ionizing radiation dose (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto , Radiação Ionizante , Linfoma/radioterapia , Linfoma , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/métodos , Diagnóstico por Imagem , Estudos Retrospectivos , Carcinogênese , Carcinogênese/efeitos da radiação , Diagnóstico por Imagem/normas , Diagnóstico por Imagem/tendências
9.
Clin Transl Oncol ; 18(5): 533-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26307754

RESUMO

PURPOSE: Survival rates among patients with lymphoma continue to improve. Strategies aimed at reducing potential treatment-related toxicity are increasingly prioritized. While radiological procedures play an important role, ionizing radiation exposure has been linked to an increased risk of malignancy, particularly among individuals whose cumulative radiation exposure exceeds a specific threshold (75 millisieverts). METHODS: Within this retrospective study, the cumulative radiation exposure dose was quantified for 486 consecutive patients with lymphoma. RESULTS: The median estimated total cumulative effective dose (CED) of ionizing radiation per subject was 69 mSv (42-118). However, younger patients (under 40 years) had a median CED of 89 mSv (55-124). CONCLUSION: This study highlights the considerable radiation exposure occurring among patients with lymphoma as a result of diagnostic imaging. To limit the risk of secondary carcinogenesis, consideration should be given to monitoring cumulative radiation exposure in individual patients as well as considering imaging modalities, which do not impart an ionizing radiation dose.


Assuntos
Diagnóstico por Imagem/efeitos adversos , Linfoma/diagnóstico por imagem , Neoplasias Induzidas por Radiação/etiologia , Radiação Ionizante , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Linfoma/complicações , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Induzidas por Radiação/patologia , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Prospectivos , Doses de Radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
Cancer Metastasis Rev ; 34(1): 129-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25726003

RESUMO

Approximately 1.6 million new cases of lung cancer are diagnosed annually (Jemal et al. CA: A Cancer Journal for Clinicians, 61, 69-90, 2011) and it remains the leading cause of cancer-related mortality worldwide. Despite decades of bench and clinical research to attempt to improve outcome for locally advanced, good performance status patients, the 5-year survival remains less than 15 % (Molina et al. 2008). Immune checkpoint inhibitor (ICH) therapies have shown a significant promise in preclinical and clinical trails to date in the treatment of non-small cell lung cancer (NSCLC). The idea of combining these systemic immune therapies with local ablative techniques is one that is gaining momentum. Electrochemotherapy (ECT) is a unique atraumatic local therapy that has had very promising objective response rates and a number of advantages including but not limited to its immunostimulatory effects. ECT in combination with ICHs offers a novel approach for dealing with this difficult disease process.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Eletroquimioterapia/métodos , Imunoterapia/métodos , Neoplasias Pulmonares/terapia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/imunologia , Terapia Combinada , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Terapia de Alvo Molecular/métodos , Resultado do Tratamento
11.
Curr Oncol ; 21(3): 134-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24940094

RESUMO

Venous thromboembolism (vte) represents a major challenge in the management of patients with cancer. The malignant phenotype is associated with derangements in the coagulation cascade that can manifest as thrombosis, hemorrhage, or disseminated intravascular coagulation. The risk of vte is increased by a factor of approximately 6 in patients with cancer compared with non-cancer patients, and cancer patients account for approximately 20% of all newly diagnosed cases of vte. Postmortem studies have demonstrated rates of vte in patients with cancer to be as high as 50%. Despite that prevalence, vte prophylaxis is underused in hospitalized patients with cancer. Studies have demonstrated that hospitalized patients with cancer are less likely than their non-cancer counterparts to receive vte prophylaxis. Consensus guidelines address the aforementioned issues and emerging concepts in the area, including the use of risk-assessment models, biomarkers to identify patients at highest risk of vte, and use of anticoagulants as anticancer therapy. Despite those guidelines, a gulf exists between current recommendations and clinical practice; greater efforts are thus required to ensure effective implementation of strategies to reduce the incidence of vte in patients with cancer.

12.
Virology ; 442(2): 97-100, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23711383

RESUMO

In 2012, an unprecedented number of four distinct, partially overlapping filovirus-associated viral hemorrhagic fever outbreaks were detected in equatorial Africa. Analysis of complete virus genome sequences confirmed the reemergence of Sudan virus and Marburg virus in Uganda, and the first emergence of Bundibugyo virus in the Democratic Republic of the Congo.


Assuntos
Surtos de Doenças , Infecções por Filoviridae/epidemiologia , Filoviridae/genética , Filoviridae/isolamento & purificação , Genoma Viral , Febres Hemorrágicas Virais/epidemiologia , RNA Viral/genética , República Democrática do Congo/epidemiologia , Filoviridae/classificação , Infecções por Filoviridae/virologia , Febres Hemorrágicas Virais/virologia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Uganda/epidemiologia
13.
Caribbean medical journal ; 74(1): 22-26, June 2012.
Artigo em Inglês | MedCarib | ID: med-18192

RESUMO

On 13 May 2012, the Quarterly Cardiology Conference program was organized by the Trinidad and Tobago Medical Association and The University of the West Indies, St. Augustine. The program provided a forum for discussion of issues related to the implementation of best practices in the management of patients requiring cardiac catheterization laboratory (Cathe Lab ) procedures. The participants who were stakeholders in the management of patients referred for catheter-based procedures reviewed best practice guidelines for patients, identified local barriers to the implementation of these best practices and made recommendations for the implementation of these best practice guidelines


Assuntos
Cateterismo Cardíaco
14.
Technol Cancer Res Treat ; 10(2): 135-44, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21381791

RESUMO

The detection of micro-metastases and individual metastatic cells in lymph node tissue by spectral methods is summarized. These methods are based on instrument-based acquisition of thousands of infrared spectra of individual tissue pixels from the tissue section, and analysis of the resulting spectral hypercube by multivariate algorithms. The method of infrared image acquisition, followed by multivariate analysis, is henceforth referred to as Spectral Histopathology (SHP). SHP produces pseudo-color images of tissue sections which reveal details that compare very favorably with images collected from hematoxylin/eosin (H and E) stained tissues in that the same tissue structures are detected. However, the infrared results are based on objective and reproducible measurements and do not depend on subjective interpretation. One of the major topics of this paper is the comparison of spectral patterns observed for the same cancer type from different patients. While this is easy in some tissue types, we found it to be difficult in tissues of very different cellularity, or tissue sections that exhibit high levels of inflammatory response. In both cases, spectral quality will be compromised due to confounding effects resulting from scattering effects. The correction of these effects now permits the direct comparison of different patient samples, and paves the way for diagnostic algorithms for cancer detection to be developed.


Assuntos
Linfonodos/patologia , Metástase Linfática/diagnóstico , Algoritmos , Análise por Conglomerados , Humanos , Análise Multivariada , Processamento de Sinais Assistido por Computador , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
16.
Ir J Med Sci ; 174(1): 58-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15868892

RESUMO

BACKGROUND: Merkel cell cancer (MCC) is an uncommon neuroendocrine skin cancer occurring predominantly in elderly Caucasians. It tends to metastasize to regional lymph nodes and viscera and is sensitive to chemotherapy but recurs rapidly. AIM: To report one such case, its response to chemotherapy and briefly review the literature. METHODS: A 73-year-old male with a fungating primary lesion on his left knee and ulcerated inguinal lymph nodes was diagnosed with MCC and treated with chemotherapy. The two largest case series and reviews of case reports were summarised. RESULTS: His ulcer healed after two cycles of carboplatin and etoposide with improvement in quality of life. Overall response rates of nearly 60% to chemotherapy are reported but median survival is only nine months with metastatic disease. CONCLUSIONS: Chemotherapy should be considered for fit elderly patients with MCC who have recurrent or advanced disease.


Assuntos
Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma de Célula de Merkel/tratamento farmacológico , Etoposídeo/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Carcinoma de Célula de Merkel/diagnóstico , Progressão da Doença , Virilha/patologia , Humanos , Joelho/patologia , Masculino , Estadiamento de Neoplasias , Neoplasias Cutâneas/diagnóstico
18.
Am J Trop Med Hyg ; 65(1): 57-63, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11504409

RESUMO

In the field, male rodents are more frequently infected with hantaviruses than females. This study examined whether patterns of immune responses against hantavirus differed between the sexes. Male and female Long Evans rats (Rattus norvegicus) were inoculated with Seoul virus, and antibody and cytokine responses, as well as virus shedding were assessed. Males were more likely to shed virus in saliva, to shed virus through multiple routes (saliva, urine, and feces), and to have viral RNA in the spleen than females. Anti-Seoul virus IgG responses were higher in males than females. In both sexes, splenic IFNgamma and IL-4 production increased following infection. After infection, males had higher Th1 immune responses (i.e., IgG2a, IFNgamma, and IL-2) than females; in contrast, Th2 immune responses (i.e., IgG1, IL-4, and IL-10) were similar between the sexes. These data suggest that immune responses to Seoul virus differ between the sexes.


Assuntos
Infecções por Hantavirus/veterinária , Orthohantavírus/imunologia , Doenças dos Roedores/imunologia , Animais , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Orthohantavírus/genética , Orthohantavírus/fisiologia , Infecções por Hantavirus/imunologia , Infecções por Hantavirus/virologia , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Interferon gama/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Masculino , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Doenças dos Roedores/virologia , Fatores Sexuais , Baço/imunologia , Baço/metabolismo , Células Th1/imunologia , Células Th2/imunologia , Eliminação de Partículas Virais/imunologia
19.
J Virol ; 74(17): 8213-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10933735

RESUMO

Field studies of hantavirus infection in rodents report that a higher percentage of infected individuals are males than females. To determine whether males were more susceptible to hantavirus infection than females, adult male and female Long Evans rats (Rattus norvegicus) were inoculated with doses of Seoul virus ranging from 10(-4) to 10(6) PFU. The 50% infective doses (ID(50)) were not significantly different for male and female rats (10(0.05) and 10(0.8) PFU, respectively). To determine whether sex differences in response to infection were related to circulating sex steroid hormones, sex steroid concentrations were manipulated and antibody responses and virus shedding were assessed following inoculation with the ID(90). Regardless of hormone treatment, males had higher anti-Seoul virus immunoglobulin G (IgG) and IgG2a (i.e., Th1) responses than females and IgG1 (i.e., Th2) responses similar to those of females. Males also shed virus in saliva and feces longer than females. Manipulation of sex steroids in adulthood did not alter immune responses or virus shedding, suggesting that sex steroids may organize adult responses to hantavirus earlier during ontogeny.


Assuntos
Estradiol/sangue , Infecções por Hantavirus/virologia , Orthohantavírus/patogenicidade , Testosterona/sangue , Animais , Castração , Chlorocebus aethiops , Estradiol/farmacologia , Fezes/virologia , Feminino , Orthohantavírus/imunologia , Infecções por Hantavirus/imunologia , Imunoglobulina G/sangue , Masculino , Radioimunoensaio , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saliva/virologia , Fatores Sexuais , Testosterona/farmacologia , Células Vero , Eliminação de Partículas Virais
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