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1.
Chem Commun (Camb) ; 52(99): 14282-14285, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27878145

RESUMO

The autocatalytic decomposition of tartaric acid on Cu(111) exhibits unique kinetics, which are linked to a hexagonal surface structure adopted at high coverage. The chirality imposed on the surface by tartaric acid throughout the explosion process is presented, and the hexagonal structure shows promise as a chiral template for enantiospecific surface chemistry.

2.
Chem Commun (Camb) ; 52(75): 11263-11266, 2016 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-27722525

RESUMO

On surfaces vicinal to Cu{111}, l-aspartic acid (l-Asp) adsorption causes steps to facet enantiospecifically into {310}R and {320}S steps. l-Asp has its highest heat of adsortion on surfaces that naturally expose the {310}R or {320}S steps but decomposes preferentially on the {310}R steps.

3.
Proc Natl Acad Sci U S A ; 107(19): 8818-23, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20421470

RESUMO

Ammonia-oxidizing archaea are ubiquitous in marine and terrestrial environments and now thought to be significant contributors to carbon and nitrogen cycling. The isolation of Candidatus "Nitrosopumilus maritimus" strain SCM1 provided the opportunity for linking its chemolithotrophic physiology with a genomic inventory of the globally distributed archaea. Here we report the 1,645,259-bp closed genome of strain SCM1, revealing highly copper-dependent systems for ammonia oxidation and electron transport that are distinctly different from known ammonia-oxidizing bacteria. Consistent with in situ isotopic studies of marine archaea, the genome sequence indicates N. maritimus grows autotrophically using a variant of the 3-hydroxypropionate/4-hydroxybutryrate pathway for carbon assimilation, while maintaining limited capacity for assimilation of organic carbon. This unique instance of archaeal biosynthesis of the osmoprotectant ectoine and an unprecedented enrichment of multicopper oxidases, thioredoxin-like proteins, and transcriptional regulators points to an organism responsive to environmental cues and adapted to handling reactive copper and nitrogen species that likely derive from its distinctive biochemistry. The conservation of N. maritimus gene content and organization within marine metagenomes indicates that the unique physiology of these specialized oligophiles may play a significant role in the biogeochemical cycles of carbon and nitrogen.


Assuntos
Processos Autotróficos/genética , Crenarchaeota/genética , Genoma Arqueal/genética , Internacionalidade , Nitrogênio/metabolismo , Água do Mar/microbiologia , Diamino Aminoácidos/biossíntese , Amônia/metabolismo , Divisão Celular/genética , Crenarchaeota/citologia , Transporte de Elétrons/genética , Metabolismo Energético/genética , Evolução Molecular , Regulação da Expressão Gênica , Metagenoma/genética , Oxirredução , Fotossíntese/genética , Filogenia , RNA não Traduzido/genética , Análise de Sequência de DNA , Transcrição Gênica
4.
Am J Surg ; 181(5): 434-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11448437

RESUMO

BACKGROUND: Some patients undergoing axillary lymph node dissection (ALND) experience postoperative pain and limited range of motion associated with a palpable web of tissue extending from the axilla into the ipsilateral arm. The purpose of this study is to characterize the previously undescribed axillary web syndrome (AWS). METHODS: To identify patients with AWS, a retrospective review was performed of all invasive breast cancer patients treated by a single surgeon (REM) between 1980 and 1996. Records were also reviewed of 4 more recent patients who developed AWS after undergoing sentinel node lymph node dissection (SLND) without ALND. RESULTS: Among 750 sequentially treated patients, 44 (6%) developed AWS between 1 and 8 weeks after their axillary procedure. The palpable subcutaneous cords extended from the axillary crease down the ipsilateral arm, across the antecubital space, and in severe cases down to the base of the thumb. The web was associated with pain and limited shoulder abduction (< or = 90 degrees in 74% of patients). AWS resolved in all cases within 2 to 3 months. AWS also occurred after SLND. Tissue sampling of webs in 4 patients showed occlusion in lymphatic and venous channels. CONCLUSIONS: AWS is a self-limiting cause of morbidity in the early postoperative period. More limited axillary surgery, with less lymphovenous disruption, might reduce the severity and incidence of this syndrome, although SLND does not eliminate its occurrence.


Assuntos
Neoplasias da Mama/cirurgia , Excisão de Linfonodo/efeitos adversos , Linfonodos/cirurgia , Dor Pós-Operatória/etiologia , Adulto , Idoso , Axila , Feminino , Humanos , Pessoa de Meia-Idade , Morbidade , Estudos Retrospectivos , Articulação do Ombro/patologia , Síndrome
5.
Radiology ; 220(2): 465-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11477253

RESUMO

Five female patients undergoing cyclosporin A therapy had newly developed breast masses. Masses were bilateral in three of the five patients and palpable in four patients. The imaging findings were suggestive of fibroadenomas, and biopsy results were used to confirm the diagnosis. With the development of new breast lesions in patients after transplantation surgery, the diagnosis of cyclosporin A-induced fibroadenomas should be considered.


Assuntos
Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/diagnóstico , Ciclosporina/efeitos adversos , Diagnóstico por Imagem , Fibroadenoma/induzido quimicamente , Fibroadenoma/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Transplante de Órgãos , Complicações Pós-Operatórias
6.
Radiology ; 219(3): 797-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11376272

RESUMO

The classic imaging findings of diabetic mastopathy, an uncommon entity manifesting in patients with a history of long-standing insulin-dependent diabetes mellitus, have been reported in the literature in women but not, to the authors' knowledge, in men. Two men with diabetic mastopathy presented with palpable breast masses. The clinical histories of the men in whom this condition was diagnosed were similar to those reported for women with the condition. The mammographic findings in both men, at presentation, were suggestive of gynecomastia.


Assuntos
Doenças Mamárias/diagnóstico , Neoplasias da Mama Masculina/diagnóstico , Diabetes Mellitus Tipo 1/complicações , Adulto , Mama/patologia , Doenças Mamárias/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Mamografia , Pessoa de Meia-Idade , Ultrassonografia Mamária
7.
AJR Am J Roentgenol ; 176(5): 1255-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11312190

RESUMO

OBJECTIVE: Because lobular carcinoma in situ is thought to be an incidental finding at breast pathology, the finding of lobular carcinoma in situ at core biopsy poses a diagnostic dilemma of radiologic-pathologic concordance. The purpose of this article is to describe the radiologic-pathologic correlation of calcifications associated with lobular carcinoma in situ of the breast. MATERIALS AND METHODS: Between July 1999 and July 2000, seven excisional biopsies resulted in findings of lobular carcinoma in situ of mammographic calcifications. The radiographic features of the calcifications were characterized by the Breast Imaging Reporting and Data System lexicon, and pathologic features were reviewed. RESULTS: Two forms of lobular carcinoma in situ were associated with calcifications: the classic form with small, uniform cells, and the pleomorphic form with larger cells frequently associated with central necrosis. On mammography, all calcifications were clustered, punctate, high density, and smaller than or equal to 0.5 mm, although mammographically visible calcifications found in the pleomorphic type tended to be larger and more dense. Additionally, infiltrating lobular carcinoma was found after surgical excision in two (40%) of five patients with pleomorphic lobular carcinoma in situ. CONCLUSION: Calcifications can be associated with lobular carcinoma in situ and therefore concordant at stereotactic core biopsy. The classic form may be incidental and clinically innocuous. The pleomorphic form is morphologically similar to ductal carcinoma in situ and may have a greater tendency for invasion.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Carcinoma in Situ/diagnóstico por imagem , Carcinoma in Situ/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Primárias Múltiplas/patologia , Adulto , Idoso , Doenças Mamárias/complicações , Doenças Mamárias/patologia , Neoplasias da Mama/complicações , Calcinose/complicações , Carcinoma in Situ/complicações , Carcinoma Lobular/complicações , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/complicações
8.
Am J Clin Pathol ; 115(1): 85-98, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11190811

RESUMO

We studied the pattern of E-cadherin expression in 183 invasive carcinomas (100 ductal, 42 lobular, 41 with mixed ductal and lobular features) and 198 in situ carcinomas (131 ductal, 53 lobular, 14 in situ with ductal and lobular features) by immunohistochemistry. We found a highly significant correlation of E-cadherin membrane expression with the histologic phenotype of the tumors. While moderate to strong membrane expression of E-cadherin was seen in all invasive and in situ ductal carcinomas, 41 of 42 invasive and 50 of 53 in situ lobular carcinomas showed complete loss of expression. All in situ carcinomas diagnosed histologically as showing mixed ductal and lobular features demonstrated complete loss of staining. Invasive carcinomas with ductal and lobular features showed 3 staining patterns: (1) complete or almost complete lack of membrane staining similar to that seen in lobular carcinomas, (2) uniform membrane expression throughout the tumor similar to ductal carcinomas, and (3) focal loss of E-cadherin staining, which correlated well with the histologic impression of focal lobular features. In tumors with histologically equivocal features, immunohistochemical detection of E-cadherin expression can be a useful diagnostic tool for the differentiation of ductal and lobular carcinomas of the breast.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Fenótipo
9.
Diagn Cytopathol ; 23(2): 73-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10888748

RESUMO

Recent studies suggest that altered expression of intercellular adhesion molecules (ICAM) in ductal carcinoma of the breast is associated with a higher incidence of metastases and decreased patient survival. In addition, the presence of significant cellular dyscohesion in cytologic smear preparations has been found to correlate with the presence of regional and distant metastases in a subset of patients. In this study, we correlate the smear pattern in preparations taken directly from surgically excised breast tumors with their immunohistochemical staining pattern, using antibodies directed against a panel of ICAM. We found excellent correlation, as all three tumors with an extremely high degree of tumor cell cohesion showed strong staining with all ICAM antibodies in the vast majority (>/=90%) of tumor cells in corresponding tissue sections. In contrast, five tumors displaying a largely dyscohesive smear pattern demonstrated decreased staining (

Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Moléculas de Adesão Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/cirurgia , Citodiagnóstico , Feminino , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade
10.
Am J Gastroenterol ; 95(4): 1078-81, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10763965

RESUMO

We report the first case of an Echinococcal cyst and focal nodular hyperplasia, two usually isolated hepatic lesions, in direct contiguity. The patient presented with right upper quadrant pain and subsequent imaging studies found a cystic and solid lesion. These studies suggested that this lesion was an hepatic adenoma, which had bled forming a hematoma. Pathological examination of the surgical resection showed Echinococcus multilocularis with contiguous focal nodular hyperplasia. Because focal nodular hyperplasia is a benign hepatic lesion the etiology of which is thought to be abnormal arterial blood flow, we postulate that the parasitic hepatic infection by E. multilocularis may have incited the formation of this contiguous hepatic lesion.


Assuntos
Equinococose Hepática/patologia , Hiperplasia Nodular Focal do Fígado/patologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Fígado/patologia
11.
Arch Ophthalmol ; 117(12): 1641-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10604671

RESUMO

Patients with systemic cancer may have a variety of ocular complaints. Most commonly these are metastases or adverse effects of therapy. Paraneoplastic syndromes, like cancer-associated retinopathy, rarely cause ophthalmic symptoms. We describe a patient with a malignant mixed mullerian tumor and cancer-associated retinopathy who had circulating serum antibodies to recoverin and cells positive for recoverin in the tumor. We discuss the typical clinical symptoms as well as the pathophysiology of this uncommon disorder.


Assuntos
Proteínas do Olho , Lipoproteínas , Tumor Mulleriano Misto/patologia , Proteínas do Tecido Nervoso , Síndromes Paraneoplásicas/patologia , Doenças Retinianas/patologia , Neoplasias Uterinas/patologia , Antígenos de Neoplasias/sangue , Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/sangue , Proteínas de Ligação ao Cálcio/sangue , Eletrorretinografia , Evolução Fatal , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Fundo de Olho , Hipocalcina , Humanos , Pessoa de Meia-Idade , Tumor Mulleriano Misto/imunologia , Tumor Mulleriano Misto/radioterapia , Síndromes Paraneoplásicas/tratamento farmacológico , Síndromes Paraneoplásicas/imunologia , Prednisona/uso terapêutico , Recoverina , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/imunologia , Neoplasias Uterinas/imunologia , Neoplasias Uterinas/radioterapia , Acuidade Visual , Campos Visuais
12.
J Clin Oncol ; 17(6): 1720-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10561208

RESUMO

PURPOSE: Recent studies have suggested that the sentinel lymph node (SLN) biopsy is an accurate alternative staging procedure for women with breast cancer. The goal of this study was to identify a subset of breast cancer patients in whom metastatic disease was confined only to the SLN. MATERIALS AND METHODS: From two institutions, we recruited 222 women with breast cancer for SLN biopsy. A SLN biopsy was performed in each patient, followed by an axillary dissection in 182 patients. Histologic and immunohistochemical cytokeratin stains were used on all SLNs. RESULTS: The SLN was identified in 220 (97. 8%) of the 225 biopsies. Evidence of metastatic breast cancer in the SLN was found in 60 (27.0%) of the 222 patients. Of these patients, 32 (53.3%) had evidence of tumor in the SLN only. By multivariate analysis, two factors were found to be significantly associated with a higher likelihood of tumor involvement in the non-SLNs: primary tumor size larger than 2.0 cm (P =.0004) and macrometastasis (> 2.0 mm) in the SLN (P =.002). Additional analysis revealed that none (0%; 95% confidence interval, 0% to 18.5%) of the 18 patients with primary tumors < or = 2.0 cm and micrometastasis to the SLN had remaining axillary lymph node involvement. CONCLUSION: The primary tumor size and metastasis size in the SLN are independent factors in predicting the incidence of tumor in the non-SLNs. Therefore, the SLN biopsy alone may be adequate for staging and/or therapy decision making in patients with primary breast tumors < or = 2.0 cm and micrometastasis in the SLN.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Biópsia , Neoplasias da Mama/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Queratinas/metabolismo , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Valor Preditivo dos Testes
13.
Hum Pathol ; 29(6): 651-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9635689

RESUMO

We present a unique case of massive splenomegaly, hepatomegaly, and lymphadenopathy caused by lipid-laden macrophages in a 50 year old white female with short-bowel syndrome treated with long-term total parenteral nutrition. Using transmission electron microscopy and special stains we were able to show that the total parenteral nutrition lipid component was composed of lipid droplets and micelles morphologically identical to those found in lipid-laden macrophages which had accumulated in the patient's reticuloendothelial system leading to massive splenomegaly, hepatomegaly (without evidence of steatosis) and lymphadenopathy. While this phenomenon has been reported in animal models, no human cases have been previously reported.


Assuntos
Emulsões Gordurosas Intravenosas/efeitos adversos , Células Espumosas/patologia , Hepatomegalia/etiologia , Doenças Linfáticas/etiologia , Nutrição Parenteral/efeitos adversos , Síndrome do Intestino Curto/terapia , Esplenomegalia/etiologia , Feminino , Células Espumosas/metabolismo , Hepatomegalia/patologia , Humanos , Metabolismo dos Lipídeos , Doenças Linfáticas/patologia , Pessoa de Meia-Idade , Esplenomegalia/patologia
14.
Cleft Palate J ; 25(1): 8-15, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3422605

RESUMO

This report addresses the emergence of proportional patterns in the early development of the human face. Fifty-nine human embryos and fetuses (7 through 26 weeks fertilization age) constituted a "normal" study sample. Midfacial cephalometric analyses were done on projected histologic sections cut frontally through the maxillary deciduous first molar tooth crowns. The midface was divided into three cephalometric zones. Data show that while each zone increases in absolute width, least change is seen in the central facial zone, with greatest change seen in the lateral-most facial zone. This pattern of proportional stability of the central facial zone becomes evident at 9 weeks gestation, at which time the changing embryonic optical axes have converged toward the midline to within several degrees of their position at birth. These data show that the central portion of the postnatal facial T-zone has a clearly recognizable prenatal antecedent as early as the ninth week in fetal life.


Assuntos
Face/embriologia , Cefalometria , Embrião de Mamíferos , Desenvolvimento Embrionário e Fetal , Olho/embriologia , Ossos Faciais/embriologia , Feminino , Feto , Idade Gestacional , Humanos , Arcada Osseodentária/embriologia , Masculino
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