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1.
Clin Oncol (R Coll Radiol) ; 34(6): e246-e253, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35033410

RESUMO

AIMS: The benefits of neoadjuvant androgen deprivation therapy (nADT) in the management of intermediate- and high-risk prostate cancer patients have been well-established. The aim of this study was to identify radiomic prognostic features derived from routine anatomic magnetic resonance imaging (MRI) sequences that can predict the response of the prostate cancer to nADT. MATERIALS AND METHODS: Patients with intermediate- and high-risk prostate cancer (with one of clinical stage ≥ T2c, Gleason score ≥7 or presenting prostate-specific antigen ≥10) who received 3 months of ADT prior to radical external beam radiotherapy were enrolled into this study. The relative blood volume and the relative blood flow were used as dynamic MRI kinetic parameters to quantify vascular changes as responses to nADT. For all pre- and post-nADT data sets, a combination of T2-weighted and contrast-enhanced T1-weighted anatomic images were used to define regions of interest (ROI) as the dominant malignant nodules (DMNs) and the benign prostate (the entire prostate with the summed DMNs being subtracted). MRI textural radiomic features associated with prostate cancer response in the literature of energy and homogeneity were selected. Pyradiomics was used to extract textural features of the ROIs. A Wilcoxon signed-rank test was carried out to investigate if there were statistically significant differences in values of radiomic features between: (i) benign prostate ROI and DMN pre-nADT; (ii) pre- and post-nADT of benign prostate ROI; (iii) pre- and post-nADT of DMN. Changes in radiomic features and dynamic MRI kinetic parameters were correlated using the Spearman correlation test. RESULTS: Twenty prostate cancer patients were recruited into the study. The median time between the first baseline scan and the first on-treatment scan was 91.5 days (range 82-105). One patient had no discernible tumour visible, leaving 19 patients with evaluable data for the analysis. Baseline homogeneity and energy values differed significantly between benign and malignant tissue (P < 0.01). In response to nADT, homogeneity and energy showed reciprocal changes, significantly increased in benign prostate while decreasing in the DMN. The reduction in tumour homogeneity and energy feature values showed a positive association with the decline in tumour blood flow and tumour blood volume induced by androgen deprivation as derived from dynamic MRI parameters. CONCLUSION: Energy and homogeneity radiomic features derived from MRI of benign and malignant prostate showed significant reciprocal changes in response to nADT. This study confirms the potential of these radiomic features to act as surrogate markers of tumour androgen sensitivity due to their strong association with ADT-induced physiological effects in prostate tumours.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Antagonistas de Androgênios/uso terapêutico , Androgênios/uso terapêutico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Gradação de Tumores , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
2.
Radiother Oncol ; 158: 112-117, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33636229

RESUMO

INTRODUCTION: Auto contouring models help consistently define volumes and reduce clinical workload. This study aimed to evaluate the cross acquisition of a Magnetic Resonance (MR) deep learning auto contouring model for organ at risk (OAR) delineation in head and neck radiotherapy. METHODS: Two auto contouring models were evaluated using deep learning contouring expert (DLCExpert) for OAR delineation: a CT model (modelCT) and an MR model (modelMRI). Models were trained to generate auto contours for the bilateral parotid glands and submandibular glands. Auto-contours for modelMRI were trained on diagnostic images and tested on 10 diagnostic, 10 MR radiotherapy planning (RTP), eight MR-Linac (MRL) scans and, by modelCT, on 10 CT planning scans. Goodness of fit scores, dice similarity coefficient (DSC) and distance to agreement (DTA) were calculated for comparison. RESULTS: ModelMRI contours improved the mean DSC and DTA compared with manual contours for the bilateral parotid glands and submandibular glands on the diagnostic and RTP MRs compared with the MRL sequence. There were statistically significant differences seen for modelMRI compared to modelCT for the left parotid (mean DTA 2.3 v 2.8 mm), right parotid (mean DTA 1.9 v 2.7 mm), left submandibular gland (mean DTA 2.2 v 2.4 mm) and right submandibular gland (mean DTA 1.6 v 3.2 mm). CONCLUSION: A deep learning MR auto-contouring model shows promise for OAR auto-contouring with statistically improved performance vs a CT based model. Performance is affected by the method of MR acquisition and further work is needed to improve its use with MRL images.


Assuntos
Aprendizado Profundo , Neoplasias de Cabeça e Pescoço , Cabeça , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Espectroscopia de Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador
3.
Science ; 201(4350): 9-16, 1978 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-17777737

RESUMO

A lightning flash that struck the 150-meter weather tower at Kennedy Space Center was studied by several research groups using varioul techniques. The flash had unusually large peak currents and a stepped leader of relatively short duration. The charged regions neutralized by the three return strokes were located within a horizontal layer between heights of about 6 and 8 kilometers, where environmental temperatures were about -10 degrees to -20 degrees C. The charge source for the first return stroke coincided with a vertical shaft of precipitation inferred to have been graupel or hail. Charge sources for subsequent strokes were near the edge of the detectable precipitation echo. The overall channel length was about 10 kilometers. A Vertically oriented intracloud discharge occurred after the three return strokes.

5.
Ann R Coll Surg Engl ; 100(4): 285-289, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29364008

RESUMO

Background Increases in life expectancy has meant that a higher proportion of patients presenting to surgical assessment units are now elderly. Abdominal computed tomography (CT) can provide early and accurate diagnosis in the elderly, even in the presence of incomplete clinical and biological findings. The aim of this study was to investigate the use of early CT imaging in elderly patients presenting directly to the surgical assessment unit. Materials and methods All consecutive patients aged 65 years and over admitted directly to the surgical assessment unit between January 2017 and April 2017 were identified. Data were collected on demographics, laboratory investigations, radiological investigations and hospital admission. The primary outcome measure was overall length of stay. Results A total of 200 consecutive patients were identified and included over a six-month period. This comprised 110 women and 90 men with a median age of 78 years (range 64-98 years). A total of 83 patients underwent CT on admission to the surgical assessment unit. White cell count (WCC) and C-reactive protein (CRP) results were significantly higher in patients undergoing CT (P = 0.001). Median length of stay for patients undergoing CT was 5 days (range 1-19 days). This was significantly lower than those patients not receiving CT imaging, at 6 days (range 1-105 days; P = 0.034). Discussion CT should be considered as a first-line investigation when elderly patients with an acute abdomen are admitted to surgical assessment units. Early CT can accelerate hospital discharge and decrease overall length of hospital stay.


Assuntos
Abdome Agudo/diagnóstico por imagem , Tempo de Internação/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Abdome Agudo/sangue , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Estudos de Viabilidade , Feminino , Humanos , Contagem de Leucócitos , Masculino , Admissão do Paciente/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Estudos Retrospectivos
6.
J Comp Neurol ; 178(3): 487-94, 1978 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-649782

RESUMO

Although the cat's canine tooth has become the accepted model for the electrophysiological study of dental sensory mechanisms no examination of its innervation has been carried out at the electron-microscopical level. This study looked at the number and size distribution of both myelinated and non-myelinated fibers in the crown of the cat's canine. The material examined was prepared by routine methods and the measurements taken from electron-microscopical montages of pulpal cross-sections. The measurements were made using a Quantimet 720 image analysis system. In one complete cross-section 3,470 fibers were counted. Eighty-one percent of these were non-myelinated with a modal diameter of 0.35 micron. The modal diameter of the myelinated fibers was 2.5 micron. The relative preponderance of non-myelinated fibers increased from core to periphery. The largest myelinated fibers were concentrated in the core. The fiber size distribution was similar in the single complete and two partial sections examined. It is concluded that all the fibers in the crown of the cat's canine would be contained in the A-delta and C groups and that the strikingly large number of fibers present suggests that the peripheral pulp has a dense innervation, many of the cell processes found there being unsheathed axons.


Assuntos
Dente Canino/inervação , Nervos Periféricos/anatomia & histologia , Animais , Gatos , Contagem de Células , Polpa Dentária/inervação , Cães , Fibras Nervosas Mielinizadas , Especificidade da Espécie
7.
Obstet Gynecol ; 53(3 Suppl): 92S-97S, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-424140

RESUMO

Adenocarcinoma of the vagina is an uncommon tumor. Many theories have been postulated for its etiology and tissue origin. Its occurrence in young women exposed in utero to diethylstilbestrol has pointed to estrogen influence as a possible etiologic factor. A case of adenocarcinoma of the vagina in a patient with gonadal dysgenesis is presented, and histologic and electron-microscopic observations are discussed. This patient is unique in that development of the vaginal neoplasm occurred in the absence of estrogen influence.


Assuntos
Adenocarcinoma/complicações , Síndrome de Turner/complicações , Neoplasias Vaginais/complicações , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Feminino , Humanos , Cariotipagem , Síndrome de Turner/genética , Síndrome de Turner/patologia , Neoplasias Vaginais/genética , Neoplasias Vaginais/patologia
8.
Obstet Gynecol ; 53(2): 253-5, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-418985

RESUMO

A Swan-Ganz catheter has been used in 10 consecutive patients undergoing pelvic exenteration and has made the intraoperative and postoperative management of these patients a much easier task. Use of this catheter eliminates the guesswork involved in managing fluid and volume status by providing an accurate assessment of left ventricular end diastolic pressure. The complication rate is reported as 5% and consists mostly of ruptured balloons, infection, coiling of the catheter, and cardiac irritability. There have been no complications in the 10 patients in whom we have used the catheter. We believe that the use of the Swan-Ganz catheter in these difficult-to-manage patients is justified because of its low complication rate, easy use, and the accurate valuable information obtained.


Assuntos
Cateterismo Cardíaco , Exenteração Pélvica , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Feminino , Humanos , Cuidados Pós-Operatórios
9.
J Hosp Infect ; 56(1): 6-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14706264

RESUMO

Fly larvae have been used by many different cultures for treating wounds throughout history. Recently, their therapeutic actions have been scientifically defined. This article reviews the history of biosurgery and the most recent research, which demonstrates the therapeutic action of larvae and particularly their anti-MRSA properties.


Assuntos
Dípteros , Larva , Resistência a Meticilina , Úlcera Cutânea/terapia , Infecções Estafilocócicas/complicações , Staphylococcus aureus , Animais , Doença Crônica , Infecção Hospitalar/complicações , Infecção Hospitalar/microbiologia , Infecção Hospitalar/terapia , Desbridamento/métodos , Humanos , Úlcera Cutânea/complicações , Úlcera Cutânea/microbiologia , Cicatrização
10.
Am J Surg ; 145(6): 823-7, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6859421

RESUMO

Spontaneous pneumothorax in the apparently healthy individual is a reasonably common occurrence. In a military hospital serving a large population in the age range most at risk for this entity, we have gained a wide experience with this problem. A review of our 10 year experience with spontaneous pneumothorax and its surgical treatment has been presented. In our series, a decreased male to female ratio was noted. This may reflect the increased incidence of female smokers. A total of 9.4 percent of our patients had complications of their tube thoracostomy treatment and an additional 10 percent required surgery for resolution of their problem. Our indications for pleural abrasion have been discussed. Pleural abrasion remains our mainstay of surgical therapy for treatment of recurrent spontaneous pneumothorax with acceptable morbidity.


Assuntos
Pneumotórax/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Intubação/efeitos adversos , Pneumopatias/complicações , Masculino , Pessoa de Meia-Idade , Derrame Pleural/etiologia , Pneumotórax/etiologia , Pneumotórax/terapia , Recidiva , Fatores Sexuais , Fumar , Fatores de Tempo
11.
Arch Pathol Lab Med ; 118(1): 48-51, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7506904

RESUMO

Accurate and consistent discrimination of prostatic carcinomas from benign lesions and vice versa continues to be a vexing problem in diagnostic pathology. We have tested the usefulness of the tumor marker D-galactose-beta-[1-->3]-N-acetyl-D-galactosamine in differentiating the benign from the malignant and premalignant lesions of the prostate. A sequential galactose oxidase technique (overnight incubation), followed by Schiff's reaction (15 minutes), was done on deparaffinized tissue sections of 65 carcinomas, 25 hyperplasias, 11 foci of adenosis, and 10 normal specimens. While none of the 35 benign prostates and 11 foci of adenosis expressed D-galactose-beta-[1-->3]-N-acetyl-D-galactosamine (100% specificity), 62 (95.4% sensitivity) of 65 adenocarcinomas variably expressed the marker. We therefore propose that this simple technique may have potential use in routine histopathological analysis of prostatic specimens. This marker may also serve as the basis of assays for early detection of prostatic malignancies.


Assuntos
Antígenos Glicosídicos Associados a Tumores/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Lesões Pré-Cancerosas/metabolismo , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
12.
Mil Med ; 158(1): 14-9, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8382350

RESUMO

In June 1988, the armed forces of the United States began testing prospective candidates for military service for alcohol, marijuana metabolite (THC-COOH), and cocaine metabolite (benzoylecgonine) through the Military Entrance Processing Station (MEPS) program. Comparison of the confirmed positive drug rates for pre-inductees into the Navy during the MEPS program testing period with the confirmed drug-positive rates for 5 years before and 1 year after MEPS testing showed a decrease in the confirmed positive rate for THC-COOH and an apparent initial decrease for cocaine metabolite as a result of MEPS testing. The overall results for cocaine seem to be overshadowed by other demographic factors operating in the population tested.


Assuntos
Cocaína/análogos & derivados , Dronabinol/análogos & derivados , Dronabinol/análise , Etanol/análise , Militares , Detecção do Abuso de Substâncias/estatística & dados numéricos , Adolescente , Adulto , Cocaína/análise , Dronabinol/metabolismo , Feminino , Humanos , Masculino , Fatores de Tempo , Estados Unidos
13.
Mil Med ; 157(1): 33-7, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1603375

RESUMO

Confirmed use of marijuana and cocaine in Navy and Marine Corps recruit populations was examined in terms of age, month of enlistment, recruit class size, education level, and Armed Forces Qualifications Test (AFQT) scores. Between 1982 and 1989, confirmed use of the drugs showed a seasonal variation, with the highest levels in the fall and winter. The rate for marijuana and cocaine was inversely related to the size of the recruit class (r = -0.80) and completion of high school (r = -0.82). The recruit class is larger and younger in the summer. AFQT scores were directly related to age. Education level appears to be one major determinant in addressing drug use.


Assuntos
Cocaína , Abuso de Maconha/epidemiologia , Militares/estatística & dados numéricos , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Estudos Transversais , Humanos , Incidência , Abuso de Maconha/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Estados Unidos/epidemiologia
14.
Mil Med ; 161(7): 382-6, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8754710

RESUMO

We studied the epidemiology, morbidity, and etiology of dermatologic and non-human immunodeficiency virus venereologic disease (Derm/STD) aboard a deployed aircraft carrier to revise Derm/STD training objectives for shipboard primary care providers. Onboard supplies for treatment of Derm/STD were also evaluated. Over 3 months, 929 Derm/STD patients were treated for 1,320 diagnoses generating 2,011 visits. Derm/STD caused 22% of the total morbidity. Pyoderma alone accounted for nearly one-half of that morbidity and involved many work-center groups. Air wing, aircraft maintenance, and engineering work-center groups had lower burdens of pyoderma. Bacterial cultures were performed on 248 exudative dermatoses. Staphylococcus aureus was the dominant pathogen and was overwhelmingly sensitive in vitro to common, inexpensive antibiotics. Strategies to encourage prevention, earlier diagnosis, and rapid treatment of Derm/STD by deployed primary care providers are discussed.


Assuntos
Militares , Medicina Naval , Infecções Sexualmente Transmissíveis/epidemiologia , Dermatopatias/epidemiologia , Humanos , Incidência , Morbidade/tendências , Medicina Naval/tendências , Fatores de Risco , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/terapia , Navios , Dermatopatias/diagnóstico , Dermatopatias/terapia , Estados Unidos
15.
Ann R Coll Surg Engl ; 96(8): 575-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25350177

RESUMO

Significant disagreement and debate persist regarding several aspects of the optimal surgical management of oesophageal cancer. We address some of these issues based on our consecutive series of 165 patients undergoing oesophageal resection (reported in full elsewhere) and the available literature. The areas considered are controversial but we argue in favour of a 'traditional' two-stage open approach (Ivor-Lewis), leaving the pylorus alone, making no attempt to perform a radical lymphadenectomy and fashioning a hand sewn anastomosis.


Assuntos
Anastomose Cirúrgica/métodos , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Humanos , Excisão de Linfonodo
16.
Ann R Coll Surg Engl ; 96(2): 151-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24780676

RESUMO

INTRODUCTION: Significant controversy persists over the optimum surgical management of oesophageal carcinoma. The authors report on a consecutive personal series of open transthoracic oesophageal resections. METHODS: Data relating to resections performed between mid-1993 and the end of 2010 were analysed. Patient and tumour assessment evolved over this period. Preoperative chemotherapy in appropriate cases was introduced in 2002. A laparotomy and right lateral thoracotomy approach (Ivor-Lewis) was used. In all cases the pylorus was not interfered with, no attempt was made to perform a radical lymphadenectomy but surgical strategy was focused on producing an R0 resection and a hand sewn anastomosis was fashioned. RESULTS: A total of 165 resections were performed; 130 patients (80%) were male. The median age was 66 years (range: 31-82 years). Eighty per cent had an adenocarcinoma. Sixty-four per cent of the tumours were T3/T4 and sixty-two per cent node positive. Forty patients (24%) had an involved circumferential resection margin (CRM). Five patients (3.0%) had no resection and a quarter (26%) developed morbidity of some form. There was one clinical anastomotic leak (0.6%) and three benign strictures requiring dilation (1.8%). In-hospital mortality was 3.0% (5 patients). Disease specific survival at one, two and five years was 77%, 42% and 36% respectively. Neither CRM involvement nor preoperative chemotherapy influenced survival significantly. No patient required intervention to disrupt the pylorus. CONCLUSIONS: Excellent outcomes are achievable following open transthoracic oesophagectomy without radical lymphadenectomy using a hand sewn gastro-oesophageal anastomosis and without disrupting the pylorus.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/mortalidade , Anastomose Cirúrgica/estatística & dados numéricos , Neoplasias Esofágicas/mortalidade , Esofagectomia/mortalidade , Esôfago/cirurgia , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Excisão de Linfonodo/mortalidade , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Padrões de Prática Médica/estatística & dados numéricos , Reoperação/mortalidade , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Estômago/cirurgia , Análise de Sobrevida , Técnicas de Sutura , Tomografia Computadorizada por Raios X , Resultado do Tratamento
17.
J Okla Dent Assoc ; 99(3): 28, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18274386
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