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2.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37737699

RESUMO

We describe an inertial rotation sensor with a 30-cm cylindrical proof-mass suspended from a pair of 14 µm thick BeCu flexures. The angle between the proof-mass and support structure is measured with a pair of homodyne interferometers, which achieve a noise level of ∼5prad/Hz. The sensor is entirely made of vacuum compatible materials, and the center of mass can be adjusted remotely.

3.
Breast ; 15(3): 370-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16185870

RESUMO

Accurate reporting of the residual tumor size by pathologists after neoadjuvant chemotherapy is an important component of a breast cancer. Recent literature reported comparisons regarding the accuracy of clinical and radiological residual tumor size findings using the histopathology as a "gold standard". However, the histopathological methods of measuring the residual tumor size are not standardized. Most pathologists use the tumor size measured by the gross examination. We collected 32 patient samples and compared the residual tumor size by gross and microscopic pathologic examinations. Using microscopic tumor size as the gold standard, our study showed gross tumor size is overestimated in 25%, underestimated in 56% and correlated to the final microscopic tumor size in 19% of the cases after neoadjuvant chemotherapy. Determining accurate residual tumor size to estimate pathologic response to chemotherapy is essential. We attempted to provide guidelines for pathology reporting post-neoadjuvant chemotherapy on breast cancers.


Assuntos
Neoplasias da Mama/patologia , Neoplasia Residual/patologia , Patologia Cirúrgica/normas , Adulto , Idoso , Neoplasias da Mama/classificação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Imageamento por Ressonância Magnética , Mastectomia , Mastectomia Segmentar , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasia Residual/classificação
4.
Cancer Epidemiol Biomarkers Prev ; 9(2): 175-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10698478

RESUMO

The oncogene c-myc is a key regulator of cell cycle progression (from G1 to S phase). The amplification of c-myc can either induce cell proliferation or apoptosis. As a part of our ongoing effort to develop methods for multiple tumor marker analysis, this study was carried out to determine whether biomarkers such as c-myc amplification could be analyzed on genetic materials collected from archival fine-needle aspiration (FNA) smears. A novel comparative PCR analysis was used to analyze c-myc amplification semiquantitatively. Genomic DNA was prepared using cells obtained from archival FNA materials that had undergone quantitative fluorescence image analysis (QFIA) for other biomarkers. Of the 72 cases selected from 1995 for this study, 53 had an adequate amount of DNA for analysis. A novel comparative PCR analysis was used to analyze c-myc amplification quantitatively. For each batch of experiments, DNA from the high c-myc expressing cells, HL-60, and DNA from the low expressing cells, K562, were served as positive and negative controls, respectively. c-myc amplification was observed in 16 (94.1%) of 17 malignant lesions, 5 (41.7%) of 12 proliferative breast diseases with nuclear atypia, and 4 (16.7%) of 24 other benign lesions (fibroadenoma or fibrocystic disease). The overall difference of c-myc expression among these groups was highly significant by chi2 analysis (P = 0.0002). We conclude that multiple phenotypic markers and genotypic markers may be combined in a risk assessment biomarker profile on small FNA samples that can be obtained on multiple occasions relatively noninvasively from the patient. The results of this study suggest that c-myc amplification may be a biomarker of breast cancer risk. However, additional large, prospective studies are needed to confirm the current observation.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Mama/patologia , Amplificação de Genes/genética , Genes myc/genética , Reação em Cadeia da Polimerase , Adulto , Idoso , Apoptose , Biópsia por Agulha , Neoplasias da Mama/patologia , Divisão Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Manejo de Espécimes
5.
Acta Cytol ; 43(3): 339-43, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10349359

RESUMO

OBJECTIVE: To perform a retrospective study evaluating the triple test for inadequate fine needle aspiration (FNA) biopsies of palpable breast lesions with a two-year clinical follow-up. STUDY DESIGN: All aspirates were reviewed and assessed for cellular adequacy in a one-year period. Specimen adequacy was based on the most stringent criteria, the presence of six or more epithelial cell clusters composed of at least six cells each. In all cases, clinical and radiologic results were reviewed and compared with the histologic outcome. RESULTS: Aspirates from 61 of 263 (23%) patients with palpable breast lesions that yielded nondiagnostic results were examined. The study showed a misdirected FNA rate of 21% and a misinterpreted rate of 1.6%. The other 77% of cases had benign surgical biopsies and/or clinical follow-up. Three of 61 (4.9%) cases with nondiagnostic smears were found to have cancer; two were inadequate due to misdirected aspirates, and one was misinterpreted microscopically. All cancer cases underwent surgical removal of the mass as a result of clinical or radiologic suspicion. CONCLUSION: We recommend utilizing the three diagnostic parameters of cytology, clinical findings and radiology, the "triple test," to achieve the best diagnostic accuracy in breast FNAs and to enhance patient management.


Assuntos
Biópsia por Agulha , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Masculino , Mamografia , Palpação , Estudos Retrospectivos
6.
Hum Pathol ; 30(2): 123-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10029438

RESUMO

The pathobiology of precursor lesions leading to invasive pancreatic adenocarcinoma remains a controversial area, but knowledge of the mechanisms of tumorigenesis may lead to possibly earlier detection, prevention, and treatment in the future. We hypothesize that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions and are part of a continuous developmental spectrum evolving into ductal adenocarcinoma of the pancreas. To further define this sequence, we studied the immunohistochemical markers HER-2/neu, K-ras, and p53 in 15 adenocarcinomas and 15 nonmalignant specimens of the pancreas. The 15 nonmalignant specimens of the pancreas included both normal pancreas and chronic pancreatitis. Overall, HER-2/neu was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 30, 11 of 20 (55%), 10 of 15 (67%), and 12 of 15 (80%), respectively, with progressive increase in the intensity of staining; p53 was positive in 1 of 30 (3%), 0 of 20, 3 of 15 (20%), and 13 of 15 (80%), respectively, and K-ras was positive in 1 of 30 (3%), 6 of 20 (30%), 11 of 15 (73%), and 8 of 15% (53%), respectively. These data support the hypothesis that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions, and, in a fashion similar to that in colorectal tumorigenesis, pancreatic cancer seems to accumulate progressive genetic alterations.


Assuntos
Adenocarcinoma/metabolismo , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptor ErbB-2/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Proteínas ras/biossíntese , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hiperplasia/metabolismo , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/patologia
7.
Cancer Epidemiol Biomarkers Prev ; 7(11): 1027-33, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9829712

RESUMO

Fine-needle aspiration (FNA) is a sensitive and cost-effective method for evaluating breast lesions. However, the diagnosis of early premalignant lesions is less reliable by FNA because of a lack of distinctive cytological features. Accurately defining the risk of such lesions at the individual level may have significant impact in breast cancer prevention and management. The main objective of this preliminary study was to develop a method to study multiple biomarkers on archival FNA slides using quantitative fluorescence image analysis (QFIA). Biomarkers p53, G-actin, and DNA content were labeled with an immunofluorescence technique and measured by QFIA simultaneously on a single cell basis. QFIA allows the labeling and measurement procedures to be carried out in situ, without the need to remove cells from the slide while preserving the morphology of the cells. FNA slides from 72 incident patients were obtained for this study. Fifty-six cases had an adequate number of cells for the actual analysis (25 benign breast lesions, 14 proliferative breast diseases with nuclear atypia, and 17 malignant lesions). The DNA content (> or = 5c) and G-actin (average gray mean, > 90) were positive in 81% and 88% of malignant lesions, respectively. These were significantly higher than the corresponding positive rates in benign lesions (7% and 15%, respectively; P <0.01 for both). None of the benign cases were positive for G-actin and DNA simultaneously, and none of the malignant cases were negative for G-actin and DNA together. p53 was positive in 33% of malignant lesions and 8% of benign lesions (P >0.05). Our study demonstrates the feasibility of evaluating multiple biomarkers by QFIA on archival FNA-fixed specimens. The G-actin and DNA content assayed by QFIA may be potential intermediate end point markers for breast cancer individual risk assessment.


Assuntos
Actinas/análise , Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , DNA de Neoplasias/análise , Proteína Supressora de Tumor p53/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Neoplasias da Mama/genética , Feminino , Imunofluorescência , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes
8.
Acta Cytol ; 41(5): 1528-33, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9305396

RESUMO

BACKGROUND: The diagnosis of a peripheral pulmonary nodule presents a challenge due to many diagnostic possibilities and pitfalls. We describe the cytologic features of solitary fibrous tumor of the pleura, differential diagnoses, pertinent immunohistochemical stains and histogenesis. CASES: Two cases of solitary fibrous tumor of the pleura showed two cell populations on cytologic preparations; mesothelial cells and spindle cells. The neoplastic spindle cell component was positive for CD-34 and vimentin but not for cytokeratin. CONCLUSION: Solitary fibrous tumor of the pleura is rare but should be included in the differential diagnosis of a peripheral pulmonary nodule. Fine needle aspiration biopsy is a safe and rapid method of providing a confirmatory diagnosis.


Assuntos
Neoplasias de Tecido Fibroso/diagnóstico , Neoplasias Pleurais/diagnóstico , Idoso , Antígenos CD34/análise , Biópsia por Agulha , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecido Fibroso/química , Neoplasias Pleurais/química , Vimentina/análise
9.
Acta Cytol ; 41(4 Suppl): 1373-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9990278

RESUMO

BACKGROUND: Fibromatosis colli, a common cause of congenital muscular torticollis, should be differentiated from other neck masses in infants. Invasive diagnostic and therapeutic measures should be avoided. CASES: Three infants under the age of 2 months presented with neck masses--a clinical suspicion of malignancy, lymphadenopathy and teratoma. The cytologic findings included dyshesive multinucleated skeletal muscle fragments showing degenerative and atrophic changes within a background of scattered reactive fibroblasts. CONCLUSION: Fine needle aspiration biopsy is a safe and rapid method of providing a confirmatory diagnosis of neck masses in infants.


Assuntos
Fibroma/diagnóstico , Fibroma/patologia , Neoplasias Musculares/diagnóstico , Neoplasias Musculares/patologia , Músculos do Pescoço/patologia , Biópsia por Agulha , Fibroma/complicações , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Lactente , Recém-Nascido , Masculino , Neoplasias Musculares/complicações , Torcicolo/diagnóstico , Torcicolo/etiologia , Torcicolo/patologia
10.
Dig Dis Sci ; 42(6): 1179-83, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9201081

RESUMO

We discuss a case of lymphangioma of the small bowel that caused chronic anemia secondary to gastrointestinal blood loss. We believe that this is the first jejunal lymphangioma to be diagnosed by Sonde endoscopy. There are several other lymphatic abnormalities of the small intestine that are briefly discussed. In the Western literature, anemia or chronic gastrointestinal blood loss is an unusual presentation of lymphangioma of the small bowel.


Assuntos
Anemia Ferropriva/etiologia , Hemorragia Gastrointestinal/etiologia , Neoplasias do Jejuno/complicações , Linfangioma/complicações , Adulto , Anemia Ferropriva/diagnóstico , Feminino , Hemorragia Gastrointestinal/diagnóstico , Humanos , Neoplasias do Jejuno/diagnóstico , Linfangioma/diagnóstico
11.
Am J Clin Pathol ; 105(3): 321-6, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8602613

RESUMO

The cytologic diagnosis of pancreatic carcinoma is notoriously difficult, particularly in distinguishing benign atypia from well-differentiated adenocarcinoma. Mutation of codon 12 in the K-ras oncogene is frequently found with pancreatic cancers. Detection by polymerase chain reaction (PCR) followed by restriction endonuclease digestion can provide a powerful tool to improve and confirm diagnosis. The authors examined the utility of PCR-based detection in the diagnosis of pancreatic carcinoma using routinely obtained cytology smears that could be collected at most hospitals. Pancreatic cytology smears were collected retrospectively from 60 patients. DNA was extracted from the slides and amplified by PCR using mismatched primers that generated a Bst-N1 recognition site with the wild type codon 12 but not with the mutant allele. Results were compared with clinical follow-up. K-ras codon 12 mutations were observed in 44 of 46 (95.7%) cases of pancreatic cancer, but not in 12 benign cases nor in 2 cases of islet cell tumor. The amplification and digestion steps proved robust and sensitive, capable of detecting mutant K-ras alleles from cytology smears that contained only small foci of suspicious cells. Our results indicate that K-ras mutation analysis can be done reliably within 1 to 2 days from routine cytology slides without special handling, increasing the sensitivity of diagnosis in ambiguous cases while maintaining cost-effective and relatively noninvasive sampling strategy.


Assuntos
Adenocarcinoma/diagnóstico , Genes ras/genética , Neoplasias Pancreáticas/diagnóstico , Mutação Puntual , Reação em Cadeia da Polimerase , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade
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