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1.
Pediatr Cardiol ; 29(1): 157-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17929079

RESUMO

A 15-year-old boy with hypoplastic left heart syndrome experienced plastic bronchitis 9 years after completion of a nonfenestrated lateral tunnel Fontan. Despite cardiac catheterization with coil embolization of collateral vessels and initiation of a pulmonary toilet regimen, including aerosolized tissue plasminogen activator, he continued to expectorate large acellular-mucinous casts. Finally, after optimization of cardiac function with the addition of carvedilol, the expectorated casts decreased in number. This report reviews pathophysiology of plastic bronchitis cast formation and therapy in the context of this late presentation after Fontan.


Assuntos
Bronquite/etiologia , Bronquite/fisiopatologia , Carbazóis/uso terapêutico , Técnica de Fontan , Propanolaminas/uso terapêutico , Vasodilatadores/uso terapêutico , Administração por Inalação , Adolescente , Aerossóis , Bronquite/complicações , Broncoscopia , Carvedilol , Circulação Colateral , Embolização Terapêutica , Fibrinolíticos/administração & dosagem , Humanos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Masculino , Indução de Remissão , Fatores de Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem
2.
Am J Surg ; 182(4): 384-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11720676

RESUMO

BACKGROUND: Interstitial laser therapy (ILT) is a technique of destroying tumor cells via thermal energy. Prior studies have shown that the procedure is safe and efficacious in laboratory animals and that complete cell death, as assessed by tetrazolium staining, is achieved in the laser treated area. DESIGN: Forty women with localized, mammographically detectable, T1 breast cancers consented to be treated with ILT and then have the treated area subsequently excised. The delay period ranged from 5 to 42 days. Prior to ILT, the diagnosis of breast carcinoma was established by stereotactic needle core biopsy. RESULTS: All 40 cases showed a characteristic gross appearance, which consisted of a series of concentric rings surrounding a cavity corresponding to the laser needle tip. The tissue immediately adjacent to the cavity appeared coagulated and showed the same "wind-swept" nuclei seen with cautery artifact. Surrounding this was a white-tan ring that histologically showed recognizable tumor. No necrosis, increased apoptosis or inflammatory infiltrate was noted in this area on hematoxylin-eosin sections. Immunostains for cytokeratin were negative in the recognizable tumor cells despite intense staining in the epithelial cells outside the laser treated area. A ring of red tan tissue which histologically consisted of necrotic tumor was seen next and this, in turn, was surrounded by a rim of vascular proliferation and fat necrosis. The breast tissue outside the zone of fat necrosis appeared to be unaffected by the laser therapy. CONCLUSIONS: ILT appears to be an effective way to treat small localized breast cancer. It is important for the pathologist to recognize the changes seen after ILT, especially the zone containing pseudoviable tumor. Cytokeratin may be a marker to identify these likely non-viable but recognizable tumor cells. The extent of the laser affected area is defined by vascular proliferation and fat necrosis.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia por Agulha , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Fotocoagulação a Laser , Pessoa de Meia-Idade , Técnicas Estereotáxicas
3.
Am J Surg ; 182(4): 389-92, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11720677

RESUMO

BACKGROUND: HER-2 overexpression is seen in 20% to 30% of invasive female breast carcinomas. Besides being prognostic, HER-2 may also be predictive of response to therapy. Similar studies in male breast carcinoma are lacking. We compared the overexpression and amplification of HER-2 in female and male breast carcinoma. DESIGN: Formalin-fixed, paraffin embedded archival material from 58 invasive male breast carcinomas and 202 invasive female breast carcinomas were immunostained for HER-2. Scoring was performed according to established guidelines. Each case was also assessed for HER-2 gene amplification by fluorescence in-situ hybridization (FISH) utilizing the PathVysion assay (Vysis corporation, Downers Grove, Illinois). RESULTS: There were 58 male patients who ranged in age from 38 to 92 years (mean 63). Thirty-five (60%) were T1 lesions and 23 (40%) were T2 lesions. Twenty-five patients (43%) had positive lymph nodes. One (1.7%) of the 58 cases showed 3+ staining of HER-2. The remaining 57 cases did not show overexpression. There was no amplification of the HER-2 gene in any of the cases. There were 202 female patients who ranged in age from 26 to 96 years (mean 52). In all, 129 (64%) were T1 lesions, 61 (30%) were T2 lesions, and 13 (6%) were T3 lesions. Fifty-two (26%) showed positive staining with HER-2 (44 cases 3+, 8 cases 2+). The remaining 150 (74%) did not show overexpression. There was amplification of HER-2 gene in 55 (27%) of the cases. Two of the cases negative by FISH were 3+ positive by IHC. CONCLUSIONS: HER-2 is overexpressed in approximately 27% of female breast carcinomas. A high level of correlation is demonstrated between IHC and FISH techniques. Gene amplification of HER-2 does not play a role in male breast carcinoma. The rate of single-copy overexpression of HER-2 appears identical in male and female breast carcinoma.


Assuntos
Neoplasias da Mama Masculina/química , Neoplasias da Mama/química , Receptor ErbB-2/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Amplificação de Genes , Genes erbB-2/genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica
4.
Am J Surg ; 182(4): 419-25, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11720684

RESUMO

BACKGROUND: Widespread screening mammography has resulted in detection of many breast cancers smaller than one cm. Image-guided percutaneous needle sampling provides accurate diagnostic and prognostic information for adjuvant therapy. Less invasive methods based on imaging techniques are emerging as an alternative to wire localization and lumpectomy. DATA SOURCES: Information presented in this overview was provided by seven investigators from five medical centers in the United States. These researchers are currently developing various techniques of image-guided percutaneous therapy of small (Tis, 1) breast cancers. CONCLUSIONS: Several percutaneous treatment modalities for treatment of early breast cancer, either excisional or in-situ ablative, are described in this overview and their potential applications are discussed.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Biópsia , Ablação por Cateter , Feminino , Humanos , Terapia a Laser , Técnicas Estereotáxicas
5.
Ann Surg Oncol ; 8(8): 675-81, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11569784

RESUMO

BACKGROUND: Up to 30% of patients with operable breast cancer and negative regional lymph nodes experience disease recurrence within 10 years. Serial sectioning and immunohistochemical staining of these nodes have revealed 9% to 30% occult metastases. METHODS: Sentinel nodes from 200 patients with T1 and T2 invasive breast carcinoma were step-sectioned at 2- to 3-mm intervals, fixed in 10% formalin, and embedded in paraffin. Sections were taken from the face of the blocks and stained with hematoxylin and eosin (H&E). The blocks were then cut completely, and sections at .25-mm intervals were stained with cytokeratin and examined. RESULTS: Tumor metastases were found in 34 patients when the sentinel nodes were examined at 2- to 3-mm intervals and in an additional 51 patients when the nodes were sectioned in their entirety at .25-mm intervals and stained with cytokeratin, bringing the total number of patients with metastases to 85. Of the 51 patients whose metastases were detected by 2- to 3-mm sectioning and cytokeratin staining, 27 had isolated tumor cells and 24 had clusters of innumerable malignant cells, all of which were visualized and confirmed by H&E staining of the adjacent sections. CONCLUSIONS: Histologic examination of sentinel nodes of patients with invasive breast cancer sectioned at 2- to 3-mm intervals and stained with H&E significantly underestimates nodal metastases. Sectioning of the entire sentinel nodes at .25-mm intervals and staining with cytokeratin detects metastases as either isolated cells or as clusters.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Carcinoma/secundário , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Neoplasias da Mama/cirurgia , Carcinoma/cirurgia , Técnicas de Cultura , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Sensibilidade e Especificidade
6.
Curr Biol ; 11(8): R326-9, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11369225

RESUMO

Nuclear migration in yeast provides a model system for studying how a cell polarizes the actin and microtubule cytoskeletons toward sites of cell growth. Recent findings indicate that cortical anchors are necessary for directing microtubule-based processes.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Núcleo Celular/metabolismo , Dineínas/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Anáfase , Proteínas de Ligação ao Cálcio/genética , Citoplasma/metabolismo , Proteínas do Citoesqueleto , Proteínas Fúngicas/genética , Saccharomyces cerevisiae
7.
J Midwifery Womens Health ; 46(1): 17-23, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11300302

RESUMO

OBJECTIVE: In 1998, the screening and treatment practices of certified nurse-midwives (CNMs) for group B streptococcal (GBS) infection during pregnancy were studied and evaluated for their consistency with the 1996 perinatal GBS prevention guidelines of the Centers for Disease Control and Prevention (CDC). METHODOLOGY: Five hundred thirty-nine surveys were completed by CNMs attending the 1998 American College of Nurse-Midwives' Convention. Of these, 502 (94.7%) reported a practice policy for GBS prophylaxis. RESULTS: The Culture-Based Approach was used by 66.7% and the Obstetrical Risk Factor Approach by 28%. Most (69%) reported using multiple culture sites, most commonly the proximal vagina and anorectal area (33.2%), followed by the distal vagina and anorectal area (26.7%), and the anorectal area and proximal and distal vagina (7.1%). Most CNMs (92.5%) reported treating GBS intrapartally, with penicillin the most frequently reported antimicrobial (55.0%) used, and most (94.2%) reporting treatment through labor until birth. CONCLUSION: Overall, GBS prophylaxis practices among survey respondents comply with 1996 CDC recommendations; however, GBS screening practices show room for improvement and the need for continuing education that emphasizes the CDC guidelines, updates as they become available, and other new literature about the topic. In addition, heightened awareness among all perinatal providers is needed with respect to CDC guidelines, especially as they pertain to variations in culture sites, identification of risk categories, and the selection of appropriate antimicrobial treatment agents.


Assuntos
Fidelidade a Diretrizes/normas , Enfermeiros Obstétricos/normas , Complicações Infecciosas na Gravidez/diagnóstico , Cuidado Pré-Natal/normas , Infecções Estreptocócicas/diagnóstico , Streptococcus agalactiae , Centers for Disease Control and Prevention, U.S. , Coleta de Dados , Feminino , Humanos , Programas de Rastreamento/normas , Guias de Prática Clínica como Assunto , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/prevenção & controle , Fatores de Risco , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/prevenção & controle , Estados Unidos
8.
Int J Impot Res ; 13(5): 251-4, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11890510

RESUMO

Between December 1996 and December 1998, 79 inflatable penile implant insertions have been performed at our institution by a single surgeon. The objective of this analysis was to compare our in-patient and out-patient experience with penile prosthesis insertion with respect to ease of performance and complication profiles. Data was collected in a prospective manner for both groups (in-patient, n = 33 and out-patient, n = 46). The two groups were compared with respect to intra-operative blood loss, operative time, time lost from work, narcotic use and complication rates. Both groups of patients experienced similar operative blood loss, essentially identical operative times, time lost from work and narcotic use. Most importantly, overall complication rates were 6% for the in-patient group and 4% for the out-patient group. Inflatable penile implant surgery is feasible in an ambulatory surgical setting. There is no difference in complication rates, loss of time from work, or intra-operative and post-operative course. Furthermore, there is a significant saving at our institution by performing the procedure in an out-patient fashion. In-patient prosthetic surgery is reserved for secondary procedures following a prior implant infection or primary implants in men with significant co-morbidities that require in-patient postoperative monitoring.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Pacientes Internados , Implante Peniano , Idoso , Analgésicos/administração & dosagem , Analgésicos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Reoperação
9.
Curr Biol ; 10(23): 1497-506, 2000 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11114516

RESUMO

BACKGROUND: Two genetic 'pathways' contribute to the fidelity of nuclear segregation during the process of budding in the yeast Saccharomyces cerevisiae. An early pathway, involving Kar9p and other proteins, orients the mitotic spindle along the mother-bud axis. Upon the onset of anaphase, cytoplasmic dynein provides the motive force for nuclear movement into the bud. Loss of either pathway results in nuclear-migration defects; loss of both is lethal. Here, to visualize the functional steps leading to correct spindle orientation along the mother-bud axis, we imaged live yeast cells expressing Kar9p and dynein as green fluorescent protein fusions. RESULTS: Transport of Kar9p into the bud was found to require the myosin Myo2p. Kar9p interacted with microtubules through the microtubule-binding protein Bim1p and facilitated microtubule penetration into the bud. Once microtubules entered the bud, Kar9p provided a platform for microtubule capture at the bud cortex. Kar9p was also observed at sites of microtubule shortening in the bud, suggesting that Kar9p couples microtubule shortening to nuclear migration. CONCLUSIONS: Thus, Kar9p provides a key link between the actin cytoskeleton and microtubules early in the cell cycle. A cooperative mechanism between Kar9p and Myo2p facilitates the pre-anaphase orientation of the spindle. Later, Kar9p couples microtubule disassembly with nuclear migration.


Assuntos
Proteínas de Transporte/metabolismo , Polaridade Celular , Proteínas de Ligação a DNA , Cadeias Pesadas de Miosina , Miosina Tipo II , Miosina Tipo V , Miosinas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/fisiologia , Proteínas de Schizosaccharomyces pombe , Fuso Acromático/fisiologia , Actinas/metabolismo , Proteínas de Transporte/genética , Citoplasma/metabolismo , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microtúbulos/metabolismo , Miosinas/genética , Proteínas Nucleares/genética , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Arch Surg ; 135(11): 1345-52, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11074894

RESUMO

HYPOTHESIS: Mammographically detected breast tumors can be completely ablated with laser energy. DESIGN: Nonrandomized control trial. SETTING: A university hospital ambulatory care center. PATIENTS: Thirty-six patients with mammographically detected well-defined breast tumors were selected. INTERVENTIONS: The diagnosis of malignant neoplasms and determination of prognostic factors were established by image-guided needle-core biopsy. Patients were treated on a stereotactic table, using a 16- to 18-gauge laser probe, with an optic fiber transmitting a predetermined amount of laser energy. A multisensor thermal probe was inserted into the breast adjacent to the laser probe to monitor treatment. In the last 10 patients, the tumor blood flow was evaluated before and after laser therapy with contrast-enhanced color Doppler ultrasound. One to 8 weeks after laser therapy, the tumors were surgically removed and serially sectioned. MAIN OUTCOME MEASURE: Complete necrosis in 66% of tumors. RESULTS: Total tumor ablation with negative margins was observed whenever 2500 J/mL of tumor was given or the thermal sensors recorded 60 degrees C. Microscopic examination at 1 week showed disintegration of malignant cells, with peripheral acute inflammatory response and at 4 to 8 weeks extensive fibrosis. Contrast-enhanced color Doppler ultrasound revealed loss of tumor circulation after therapy, and positron emission tomography scan correlated well with histologic findings. There were no systemic adverse effects. Two patients sustained 3 x 4-mm skin burns around the laser needle. CONCLUSION: A stereotactically guided minimally invasive technique may be effective for the treatment of mammographically detected breast cancer.


Assuntos
Neoplasias da Mama/cirurgia , Terapia a Laser , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Terapia a Laser/métodos , Mamografia , Pessoa de Meia-Idade , Técnicas Estereotáxicas , Ultrassonografia Doppler em Cores , Ultrassonografia Mamária
11.
Mol Biol Cell ; 11(11): 3949-61, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11071919

RESUMO

In the budding yeast Saccharomyces cerevisiae, movement of the mitotic spindle to a predetermined cleavage plane at the bud neck is essential for partitioning chromosomes into the mother and daughter cells. Astral microtubule dynamics are critical to the mechanism that ensures nuclear migration to the bud neck. The nucleus moves in the opposite direction of astral microtubule growth in the mother cell, apparently being "pushed" by microtubule contacts at the cortex. In contrast, microtubules growing toward the neck and within the bud promote nuclear movement in the same direction of microtubule growth, thus "pulling" the nucleus toward the bud neck. Failure of "pulling" is evident in cells lacking Bud6p, Bni1p, Kar9p, or the kinesin homolog, Kip3p. As a consequence, there is a loss of asymmetry in spindle pole body segregation into the bud. The cytoplasmic motor protein, dynein, is not required for nuclear movement to the neck; rather, it has been postulated to contribute to spindle elongation through the neck. In the absence of KAR9, dynein-dependent spindle oscillations are evident before anaphase onset, as are postanaphase dynein-dependent pulling forces that exceed the velocity of wild-type spindle elongation threefold. In addition, dynein-mediated forces on astral microtubules are sufficient to segregate a 2N chromosome set through the neck in the absence of spindle elongation, but cytoplasmic kinesins are not. These observations support a model in which spindle polarity determinants (BUD6, BNI1, KAR9) and cytoplasmic kinesin (KIP3) provide directional cues for spindle orientation to the bud while restraining the spindle to the neck. Cytoplasmic dynein is attenuated by these spindle polarity determinants and kinesin until anaphase onset, when dynein directs spindle elongation to distal points in the mother and bud.


Assuntos
Proteínas Fúngicas/metabolismo , Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae , Fuso Acromático/ultraestrutura , Leveduras/ultraestrutura , Anáfase/fisiologia , Sequência de Bases , Extensões da Superfície Celular/genética , Citoplasma/genética , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Dineínas/metabolismo , Proteínas Fúngicas/genética , Cinesinas , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fuso Acromático/metabolismo , Leveduras/genética , Leveduras/metabolismo
12.
Nat Cell Biol ; 2(6): E96-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10854334

RESUMO

Microtubule orientation to cortical spatial cues is essential for the fidelity of asymmetric cellular processes. A cortical microtubule-capture site, composed of Bim1 and Kar9, has now been identified in yeast. Bim1 is the yeast homologue of EB1, a binding partner of the adenomatous polyposis coli (APC), indicating that important features of this complex may be highly conserved.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/metabolismo , Cinetocoros/metabolismo , Proteínas dos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae , Sequência Conservada , Leveduras
13.
J Cell Biol ; 148(3): 441-52, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-10662771

RESUMO

The orientation of the mitotic spindle along a polarity axis is critical in asymmetric cell divisions. In the budding yeast, Saccharomyces cerevisiae, loss of the S-phase B-type cyclin Clb5p under conditions of limited cyclin-dependent kinase activity (cdc28-4 clb5Delta cells) causes a spindle positioning defect that results in an undivided nucleus entering the bud. Based on time-lapse digital imaging microscopy of microtubules labeled with green fluorescent protein fusions to either tubulin or dynein, we observed that the asymmetric behavior of the spindle pole bodies during spindle assembly was lost in the cdc28-4 clb5Delta cells. As soon as a spindle formed, both poles were equally likely to interact with the bud cell cortex. Persistent dynamic interactions with the bud ultimately led to spindle translocation across the bud neck. Thus, the mutant failed to assign one spindle pole body the task of organizing astral microtubules towards the mother cell. Our data suggest that Clb5p-associated kinase is required to confer mother-bound behavior to one pole in order to establish correct spindle polarity. In contrast, B-type cyclins, Clb3p and Clb4p, though partially redundant with Clb5p for an early role in spindle morphogenesis, preferentially promote spindle assembly.


Assuntos
Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular , Ciclina B/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Fuso Acromático/fisiologia , Proteína Quinase CDC28 de Saccharomyces cerevisiae/genética , Ciclinas/genética , Ciclinas/metabolismo , Dineínas/genética , Dineínas/metabolismo , Proteínas Fúngicas/genética , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microtúbulos/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia
14.
Cancer ; 86(6): 990-6, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10491525

RESUMO

BACKGROUND: Thirty percent of lymph node negative patients with operable breast carcinoma experience disease recurrence within 10 years. Retrospective serial sectioning of axillary lymph nodes has revealed undetected metastases in 9-30% of these patients. These occult metastases have been shown to have an adverse effect on survival. Serial sectioning (SS) is impractical for all axillary lymph nodes harvested from Levels I and II, but it is feasible if applied only to sentinel lymph nodes. METHODS: Sentinel lymph nodes from 52 patients with invasive breast carcinoma were cut at 2 mm intervals, fixed in 10% formalin, and embedded in paraffin. Sections were taken from the blocks, stained with hematoxylin and eosin (H & E), and compared with cytokeratin-stained sections taken at 0.25 mm intervals throughout the entire blocks. RESULTS: Tumor metastases were found in 6 patients (12%) when the sentinel lymph nodes were sectioned at 2 mm intervals and stained with H & E, compared with 30 patients (58%) when the same lymph nodes were serially sectioned at 0.25 mm intervals and stained with cytokeratin. Of 24 patients whose metastases were detected by SS and cytokeratin staining, 12 had isolated tumor cells and 12 had colonies of several thousand malignant cells. CONCLUSIONS: Routine histologic examination of axillary lymph nodes, including sentinel lymph nodes, in cases of breast carcinoma significantly underestimates lymph node metastases. This deficiency may be overcome by SS of the entire lymph nodes and staining with a specific monoclonal antibody. The percentage of patients found to have colonies of cells that were missed by routine sectioning corresponds closely to the percentage of "lymph node negative" patients who would be expected to relapse. The true clinical significance of these occult metastases will be determined by long term follow-up. [See editorial on pages 905-7, this issue.]


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Linfonodos/patologia , Adulto , Idoso , Anticorpos Monoclonais , Axila , Biópsia/métodos , Neoplasias da Mama/cirurgia , Carcinoma/cirurgia , Feminino , Humanos , Queratinas/análise , Linfonodos/cirurgia , Metástase Linfática , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos
15.
J Cell Biol ; 146(5): 1019-32, 1999 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-10477756

RESUMO

In the budding yeast Saccharomyces cerevisiae, the mitotic spindle must align along the mother-bud axis to accurately partition the sister chromatids into daughter cells. Previous studies showed that spindle orientation required both astral microtubules and the actin cytoskeleton. We now report that maintenance of correct spindle orientation does not depend on F-actin during G2/M phase of the cell cycle. Depolymerization of F-actin using Latrunculin-A did not perturb spindle orientation after this stage. Even an early step in spindle orientation, the migration of the spindle pole body (SPB), became actin-independent if it was delayed until late in the cell cycle. Early in the cell cycle, both SPB migration and spindle orientation were very sensitive to perturbation of F-actin. Selective disruption of actin cables using a conditional tropomyosin double-mutant also led to defects in spindle orientation, even though cortical actin patches were still polarized. This suggests that actin cables are important for either guiding astral microtubules into the bud or anchoring them in the bud. In addition, F-actin was required early in the cell cycle for the development of the actin-independent spindle orientation capability later in the cell cycle. Finally, neither SPB migration nor the switch from actin-dependent to actin-independent spindle behavior required B-type cyclins.


Assuntos
Actinas/metabolismo , Ciclo Celular , Polaridade Celular , Proteínas dos Microfilamentos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/citologia , Fuso Acromático/metabolismo , Anáfase/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Proteína Quinase CDC28 de Saccharomyces cerevisiae/genética , Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/fisiologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiologia , Polaridade Celular/efeitos dos fármacos , Ciclina B/genética , Ciclina B/fisiologia , Dineínas/genética , Dineínas/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Genes Fúngicos/genética , Genes Fúngicos/fisiologia , Hidroxiureia/farmacologia , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Mutação , Nocodazol/farmacologia , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fuso Acromático/efeitos dos fármacos , Temperatura , Tiazóis/farmacologia , Tiazolidinas , Tropomiosina/genética , Tropomiosina/metabolismo
16.
J Cell Biol ; 144(5): 977-87, 1999 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-10085295

RESUMO

We have used time-lapse digital imaging microscopy to examine cytoplasmic astral microtubules (Mts) and spindle dynamics during the mating pathway in budding yeast Saccharomyces cerevisiae. Mating begins when two cells of opposite mating type come into proximity. The cells arrest in the G1 phase of the cell cycle and grow a projection towards one another forming a shmoo projection. Imaging of microtubule dynamics with green fluorescent protein (GFP) fusions to dynein or tubulin revealed that the nucleus and spindle pole body (SPB) became oriented and tethered to the shmoo tip by a Mt-dependent search and capture mechanism. Dynamically unstable astral Mts were captured at the shmoo tip forming a bundle of three or four astral Mts. This bundle changed length as the tethered nucleus and SPB oscillated toward and away from the shmoo tip at growth and shortening velocities typical of free plus end astral Mts (approximately 0.5 micrometer/min). Fluorescent fiduciary marks in Mt bundles showed that Mt growth and shortening occurred primarily at the shmoo tip, not the SPB. This indicates that Mt plus end assembly/disassembly was coupled to pushing and pulling of the nucleus. Upon cell fusion, a fluorescent bar of Mts was formed between the two shmoo tip bundles, which slowly shortened (0.23 +/- 0.07 micrometer/min) as the two nuclei and their SPBs came together and fused (karyogamy). Bud emergence occurred adjacent to the fused SPB approximately 30 min after SPB fusion. During the first mitosis, the SPBs separated as the spindle elongated at a constant velocity (0.75 micrometer/min) into the zygotic bud. There was no indication of a temporal delay at the 2-micrometer stage of spindle morphogenesis or a lag in Mt nucleation by replicated SPBs as occurs in vegetative mitosis implying a lack of normal checkpoints. Thus, the shmoo tip appears to be a new model system for studying Mt plus end dynamic attachments and much like higher eukaryotes, the first mitosis after haploid cell fusion in budding yeast may forgo cell cycle checkpoints present in vegetative mitosis.


Assuntos
Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/citologia , Fusão Celular , Núcleo Celular/metabolismo , Dineínas/genética , Dineínas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Fuso Acromático , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
18.
Endocr Pract ; 5(1): 46-50, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-15251703

RESUMO

OBJECTIVE: To describe a patient with systemic calciphylaxis. METHODS: We present a case of a 26-year-old woman with end-stage renal disease taking intramuscular injections of erythropoietin in whom systemic calciphylaxis subsequently developed. Both clinical and laboratory findings are reviewed. RESULTS: In a 26-year-old woman with end-stage renal disease who was taking erythropoietin intramuscularly, multiple, superficial ulcerative lesions developed on both lower extremities. Despite aggressive treatment, new lesions subsequently developed. Laboratory values showed an increased calcium-phosphate product and a normal parathyroid hormone level. A skin biopsy specimen showed necrotic skin and subcutaneous fat with foci of calcification around the vessels, findings that confirmed the diagnosis of calciphylaxis. The patient then underwent subtotal parathyroidectomy and responded with initial improvement; however, her condition later deteriorated, and she died of uncontrolled pulmonary hemorrhage. CONCLUSION: Systemic calciphylaxis is a rare but devastating complication of end-stage renal disease. This condition mimics many different disorders; therefore, a high index of suspicion is essential for early recognition and diagnosis, which is assisted by biopsy specimens of skin lesions. Treatment includes subtotal or total parathyroidectomy in conjunction with autotransplantation, administration of phosphate binders, aggressive treatment with antibiotics, and lowering of the calcium-phosphate product. Even though a successful outcome is possible when this disease is recognized early and treated aggressively, the morbidity and mortality associated with systemic calciphylaxis still remain high.

19.
Am J Med Genet ; 79(4): 319-26, 1998 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-9781914

RESUMO

Patients with Klippel-Trenaunay (KT) syndrome have a complex constellation of anomalies that includes cutaneous capillary malformation (usually on an affected limb), abnormal development of the deep and superficial veins, and limb asymmetry, usually enlargement. Mixed vascular malformations may be present and include capillary, venous, arterial, and lymphatic systems. The records of 79 patients referred for vascular anomalies were reviewed and 49 were found to have the three "cardinal" anomalies of KT syndrome. Twenty-six females and 23 males had 46 affected legs (27 right legs), 23 affected arms (15 right), 21 affected trunks, and 10 affected heads. Thirty-six had only one affected quadrant, 8 had two, and 5 had three or more. Although 40 patients had increased limb girth, measurable length discrepancy was noted in only 17 individuals. Patients were evaluated using a noninvasive imaging strategy including color duplex ultrasonography, MRI, lymphoscintigraphy, and plain radiographs. Treatment included compression, pulsed-dye laser treatment, reduction of arteriovenous malformations, and orthopedic procedures for overgrowth. All KT cases in this series occurred sporadically. We speculate that KT syndromes may be due to a somatic mutation for a factor critical to vasculogenesis and angiogenesis in embryonic development.


Assuntos
Síndrome de Klippel-Trenaunay-Weber/diagnóstico por imagem , Síndrome de Klippel-Trenaunay-Weber/patologia , Síndrome de Klippel-Trenaunay-Weber/terapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Radiografia , Ultrassonografia
20.
J Cell Biol ; 139(4): 985-94, 1997 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-9362516

RESUMO

Localization of dynein-green fluorescent protein (GFP) to cytoplasmic microtubules allowed us to obtain one of the first views of the dynamic properties of astral microtubules in live budding yeast. Several novel aspects of microtubule function were revealed by time-lapse, three-dimensional fluorescence microscopy. Astral microtubules, about four to six in number for each pole, exhibited asynchronous dynamic instability throughout the cell cycle, growing at approximately 0.3-1.5 micron/min toward the cell surface then switching to shortening at similar velocities back to the spindle pole body (SPB). During interphase, a conical array of microtubules trailed the SPB as the nucleus traversed the cytoplasm. Microtubule disassembly by nocodozole inhibited these movements, indicating that the nucleus was pushed around the interior of the cell via dynamic astral microtubules. These forays were evident in unbudded G1 cells, as well as in late telophase cells after spindle disassembly. Nuclear movement and orientation to the bud neck in S/G2 or G2/M was dependent on dynamic astral microtubules growing into the bud. The SPB and nucleus were then pulled toward the bud neck, and further microtubule growth from that SPB was mainly oriented toward the bud. After SPB separation and central spindle formation, a temporal delay in the acquisition of cytoplasmic dynein at one of the spindle poles was evident. Stable microtubule interactions with the cell cortex were rarely observed during anaphase, and did not appear to contribute significantly to spindle alignment or elongation into the bud. Alterations of microtubule dynamics, as observed in cells overexpressing dynein-GFP, resulted in eventual spindle misalignment. These studies provide the first mechanistic basis for understanding how spindle orientation and nuclear positioning are established and are indicative of a microtubule-based searching mechanism that requires dynamic microtubules for nuclear migration into the bud.


Assuntos
Dineínas/fisiologia , Microtúbulos/fisiologia , Saccharomyces cerevisiae/citologia , Fuso Acromático/fisiologia , Anáfase , Núcleo Celular/fisiologia , Núcleo Celular/ultraestrutura , Proteínas de Fluorescência Verde , Proteínas Luminescentes , Microscopia de Fluorescência , Saccharomyces cerevisiae/ultraestrutura , Fuso Acromático/ultraestrutura , Telófase
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