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1.
Tumori ; 89(4 Suppl): 185-8, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12903588

RESUMO

The aim of modern senology lies in the diagnosis and treatment of non-palpable breast lesions (NPBLs). Through the diffusion of regional mammography screening the lesions being observed are continuously smaller, thus calling for more and more accurate methodology. Our experience in this area is based on the use of certain methods for retrieval and removal of NPBLs, such as Kopan's sec. philo-guide, ultrasound and advanced breast biopsy instrumentation. In our opinion methods allowing total removal of lesions in order to obtain complete histopathological characterization and enabling adequate therapeutic programs are to be preferred. In reviewing case studies a noteworthy increase of initial carcinoma (DCIS or LCIS), from 19.5% to 57.1%, has been observed in the last three years due to the extensive use of the aforementioned methods.


Assuntos
Biópsia/métodos , Neoplasias da Mama/patologia , Doenças Mamárias/diagnóstico , Doenças Mamárias/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Calcinose/diagnóstico por imagem , Carcinoma/diagnóstico por imagem , Carcinoma/epidemiologia , Carcinoma/patologia , Carcinoma/cirurgia , Carcinoma in Situ/diagnóstico por imagem , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/epidemiologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/epidemiologia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Feminino , Secções Congeladas , Humanos , Incidência , Metástase Linfática , Mamografia , Palpação , Estudos Retrospectivos
2.
AJR Am J Roentgenol ; 161(3): 629-31, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8352121

RESUMO

OBJECTIVE: Imaging-directed fine-needle aspiration biopsy can be performed with or without immediate cytologic assessment (smears). We compared the results obtained immediately from cytologic smears with the results of cell-block analysis. We wished to determine the frequency of false-negative findings on cytologic smears in patients subsequently found to have malignant tumors by cell-block analysis. MATERIALS AND METHODS: We retrospectively reviewed the records for 100 consecutive biopsies performed between January 1986 and August 1987. In each case, specimens were obtained from both a 22-gauge and a 20-gauge notched needle placed in tandem. The study group consisted of 84 patients who had results of analyses of both cytologic smears and cell blocks available for review and who had clinical or surgical correlation. RESULTS: Sixty-four (76%) of the 84 biopsies yielded malignant tumor cells, 11 yielded evidence of a benign process, and nine were not diagnostic. Malignant tumor cells were seen on the cytologic smears in 55 (86%) of the 64 patients who had malignant tumors; in the other nine patients, the malignant tumors were indicated by the cell-block analysis only. Within the group of benign disorders, in only one case (9%) was the cell block diagnostic when the cytologic smear was not. CONCLUSION: Operators performing fine-needle aspiration biopsy should be aware of the limitations of immediate cytologic evaluation. Cell-block analysis of the aspirate remaining after the smears are made can be expected to increase the diagnostic accuracy in up to 14% of patients.


Assuntos
Biópsia por Agulha , Técnicas Citológicas , Idoso , Citodiagnóstico , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista , Estudos Retrospectivos
3.
Res Microbiol ; 143(7): 683-93, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1488552

RESUMO

We have further characterized the genomic region of Streptomyces coelicolor A3(2) that contains genes involved in the biosynthesis of histidine. A 2,357-base pair fragment contained in plasmid pSCH3328 that complemented hisD mutations has been sequenced. Computer analysis revealed an open reading frame that encodes a protein with significant homology to the Escherichia coli, Salmonella typhimurium and Mycobacterium smegmatis hisD product, Saccharomyces cerevisiae HIS4C, and Neurospora crassa his3 gene products. Two other contiguous open reading frames oriented divergently with respect to hisD did not show significant similarity with any of the his genes or to other sequences included in the gene bank. S1 nuclease mapping and primer extension experiments indicate that the transcription initiation site of the his-specific mRNA coincides with the GUG translation initiation codon of the hisD cistron.


Assuntos
DNA Bacteriano/genética , Genes Bacterianos/genética , Histidina/genética , Streptomyces/genética , Sequência de Bases/genética , Histidina/biossíntese , Técnicas In Vitro , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Mapeamento por Restrição , Streptomyces/metabolismo , Transcrição Gênica
4.
Mutat Res ; 266(2): 93-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1373843

RESUMO

The effects of 5-azacytidine (5-AZ) and mitomycin C (MMC), administered by larval feeding, on crossing-over were measured in Drosophila melanogaster male germ cells of a DNA repair-proficient and a repair-deficient (mei-9L1) strain. Both 5-AZ and MMC are effective inducers of male crossing-over. The estimated number of induced recombination events was higher in repair-proficient than in mei-9L1 males. The apparently lower sensitivity of mei-9L1 males to crossing-over induction may be the result of an incomplete crossing-over process.


Assuntos
Azacitidina/farmacologia , Troca Genética/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Mitomicina/farmacologia , Animais , Drosophila melanogaster/genética , Larva/efeitos dos fármacos , Masculino , Recombinação Genética/efeitos dos fármacos
6.
Minerva Stomatol ; 39(7): 551-63, 1990 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-2280754

RESUMO

The identification of prognostic factors which influence the long-term results of dental retransplantation and autotransplantation is one of the main aims of clinical research whose principal scope is remove or alter those factors which have a negative influence on outcome, and to identify the causes of failure and areas for improvement. The paper reports the most significant results of a clinical survey which was carried out on 135 patients who had undergone retransplantation and/or autotransplantation and were then followed for 8 years.


Assuntos
Reimplante Dentário , Dente/transplante , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Prognóstico , Fatores de Tempo , Reimplante Dentário/métodos , Reimplante Dentário/estatística & dados numéricos , Transplante Autólogo
7.
Gene ; 90(1): 31-41, 1990 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-2199329

RESUMO

Biochemical and genetic data indicate that in Streptomyces coelicolor A3(2) the majority of the genes involved in the biosynthesis of histidine are clustered in a small region of the chromosome [Carere et al., Mol. Gen. Genet. 123 (1973) 219-224; Russi et al., Mol. Gen. Genet. 123 (1973) 225-232]. To investigate the structural organization and the regulation of these genes, we have constructed genomic libraries from S. coelicolor A3(2) in pUC vectors. Recombinant clones were isolated by complementation of an Escherichia coli hisBd auxotroph. A recombinant plasmid containing a 3.4-kb fragment of genomic DNA was further characterized. When cloned in the plasmid vector, pIJ699, this fragment was able to complement S. coelicolor A3(2) hisB mutants. Overlapping clones spanning a 15-kb genomic region were isolated by screening other libraries with labeled DNA fragments obtained from the first clone. Derivative clones were able to complement mutations in four different cistrons of the his cluster of S. coelicolor A3(2). Nucleotide sequence analysis of a 4-kb region allowed the identification of five ORFs which showed significant homology with the his gene products of E. coli. The order of the genes in S. coelicolor A3(2) (5'--hisD-hisC-hisBd-hisH-hisA-3') is the same as in the his operon of E. coli.


Assuntos
Genes Fúngicos , Histidina , Streptomyces/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Escherichia coli/genética , Teste de Complementação Genética , Dados de Sequência Molecular , Plasmídeos , Mapeamento por Restrição
9.
Stomatol Mediterr ; 8(4): 339-42, 1988.
Artigo em Italiano | MEDLINE | ID: mdl-3274170

RESUMO

After an analysis of the prosthetic troubles about atrophic edentulous ridges, the Authors describes the lowering mental nerve operation and consider its therapeutic benefit.


Assuntos
Nervo Mandibular/cirurgia , Boca Edêntula/reabilitação , Processo Alveolar/cirurgia , Humanos , Procedimentos Cirúrgicos Pré-Protéticos Bucais
12.
Diagn Cytopathol ; 4(2): 106-12, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2468459

RESUMO

To evaluate the sensitivity and specificity of diagnosing Pneumocystis carinii pneumonia (PCP) by Papanicolaou-stained bronchial brushing and wash/lavage specimens obtained by fiberoptic bronchoscopy, the cytologic preparations and clinical records from 58 immunocompromised patients were reviewed. Bronchial brushings and wash/lavage specimens were examined using methenamine silver (Grocott) and Papanicolaou stains. Pneumocystis carinii pneumonia was recognized with Papanicolaou stain by identifying distinctive alveolar casts, which frequently contained collections of encysted sporozoites. Thirty cases of PCP were identified, and Grocott-stained bronchial wash/lavage specimens were positive in 29 instances (97%). Grocott staining of the transbronchial biopsy was positive for PCP in 18 of 22 specimens (82%). Bronchial brushings were insensitive, yielding a positive specimen in only 30% of cases of PCP. Alveolar casts of PCP were identified by Papanicolaou-stained slides of wash/lavage specimens in 83% of cases of Pneumocystis pneumonia. These proteinaceous alveolar casts were not seen in other pulmonary disorders. Encysted sporozoites were found in 56% of cases in which Papanicolaou-stained alveolar casts were identified. We conclude that the diagnosis of PCP can be made rapidly and reliably on the Papanicolaou-stained bronchial wash/lavage or bronchial brush specimens by detecting the characteristic alveolar casts, which contain P. carinii-encysted sporozoites. The presence of encysted sporozoites within alveolar casts is pathognomonic for PCP, and methenamine silver stains can be eliminated in those cases in which encysted sporozoites are identified.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Pneumonia por Pneumocystis/diagnóstico , Humanos , Síndromes de Imunodeficiência/complicações , Infecções Oportunistas/complicações , Pneumonia por Pneumocystis/complicações , Estudos Retrospectivos , Coloração e Rotulagem
13.
Acta Cytol ; 31(3): 330-4, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3473869

RESUMO

Psammoma bodies are concentric, laminated microcalcifications that are regarded as nearly specific markers in the thyroid gland for the presence of papillary carcinoma. While psammoma bodies have been seen rarely in some benign thyroid diseases, there appear to be no reports of psammoma body formation in lymphocytic or Hashimoto's thyroiditis. We report a case of Hashimoto's thyroiditis in which psammoma bodies were identified in a fine needle aspiration specimen of the thyroid and in histologic sections of the right thyroid lobectomy; papillary carcinoma was not found in either specimen. We conclude that psammoma bodies may be seen in any benign process, such as nodular goiter or lymphocytic thyroiditis, that produces reactive papillary hyperplasia of thyroid epithelium, as well as in papillary carcinoma. However, the finding of psammoma bodies in a fine needle aspirate without corroborating cytologic evidence of papillary cancer is still an indication for surgical removal of the thyroid nodule since these structures are reliable markers for occult papillary carcinoma of the thyroid, despite the rarity of their formation in benign diseases.


Assuntos
Biópsia por Agulha , Glândula Tireoide/patologia , Tireoidite Autoimune/patologia , Adulto , Biópsia por Agulha/métodos , Calcinose/diagnóstico , Grânulos Citoplasmáticos/patologia , Grânulos Citoplasmáticos/ultraestrutura , Feminino , Histocitoquímica , Humanos , Tireoidite Autoimune/fisiopatologia
14.
Radiology ; 151(3): 569-73, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6718709

RESUMO

Although most often recognized in neonates and young children, congenital cystic adenomatoid malformation of the lung (CCAM) occasionally appears in later years. Three patients, aged 35, 24, and 7 years, are reported. Chest radiographs in each case suggested a localized patchy density, a cystic mass, or a multicystic mass, but computed tomography (CT) best demonstrated the cystic and solid components while ruling out bronchiectasis or major bronchial obstruction. Bronchography contributed no further diagnostic information compared with CT. Each patient underwent lobectomy. Histologically, the characteristic overgrowth of bronchiolar elements replacing normal parenchymal architecture was accompanied by some superimposed inflammatory change. Each patient had a history of pneumonia, and in such patients, characteristic radiographic features should suggest the possibility of late presentation of CCAM.


Assuntos
Pulmão/anormalidades , Adulto , Broncografia , Criança , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Fatores de Tempo , Tomografia Computadorizada por Raios X
15.
Am J Surg Pathol ; 8(3): 193-202, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6703195

RESUMO

Congenital cystic adenomatoid malformation of the lung presents mainly in neonates, is rare in children beyond infancy, and has not been reported in adults. Two adult males (aged 24 and 35) had congenital cystic adenomatoid malformation of the right and left lower lobes respectively. A third case, that of a 7-year-old girl, provided the link between the typical neonatal and these adult cases. All three lesions consisted of single or multiple macroscopic cysts, as well as a network of interconnecting spaces (the adenomatoid component). The lining varied from pseudostratified columnar ciliated, to simple mucinous and cuboidal epithelium. Abundant smooth muscle was present in two cases. Cartilage was absent in all three cases. The absence of inflammation is typical of the lesion in neonates. By contrast, all three of our patients had clinical and pathologic evidence of chronic inflammation. We postulate that congenital cystic adenomatoid malformation, when confined to a lobe or segment, may be clinically silent in infancy and may present as pneumonia associated with a cystic lesion on chest x-ray in childhood or later life.


Assuntos
Pulmão/anormalidades , Adulto , Criança , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pulmão/cirurgia , Pulmão/ultraestrutura , Masculino , Tomografia Computadorizada por Raios X
17.
J Biol Chem ; 250(21): 8376-81, 1975 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-1104602

RESUMO

Initiation of transcription of the Escherichia coli histidine (his) operon in vitro has been analyzed. The DNA of a specialized transducing phage, ø80dhis, was used as a template, and his RNA was measured by RNA/DNA hybridization. Taking advantage of the fact that E. coli RNA polymerase cannot initiate transcription when the nucleoside triphosphates are present at very low (5 muM) concentration, his RNA initiation was primed by dinucleoside monophosphates. It has been found that his RNA synthesis can be stimulated by one of the three dinucleotides CpA, ApA, and ApG. Under these conditions, it is the initiation of his RNA synthesis that is stimulated. Stimulation of his RNA synthesis by the three dinucleotides apparently occurs at a single initiation site, as judged by the nonadditivity of the effects of the three dinucleotides. This was further confirmed by the effect of phosphoribosyltransferase (the first enzyme of histidine biosynthesis, which specifically represses the synthesis of his RNA) on ApA primed RNA synthesis. Addition of his protein results in a sharp decrease of his RNA synthesis, with no effect whatsoever on the levels of RNAa transcribed from other regions of the template. Our data suggest that the 5' -terminal sequence of his RNA made in vitro is ApApG and that the base immediately preceding this sequence is C.


Assuntos
Escherichia coli/metabolismo , Histidina/biossíntese , Oligonucleotídeos/farmacologia , Óperon , Transcrição Gênica/efeitos dos fármacos , Amidofosforribosiltransferase/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/efeitos dos fármacos , Cinética , Hibridização de Ácido Nucleico , Relação Estrutura-Atividade , Moldes Genéticos
19.
J Bacteriol ; 116(2): 656-62, 1973 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4583246

RESUMO

The defective prophage phi80ilambdac(I)857dhis has been mapped through both marker rescue and deletion analysis. Deletions have been isolated which put residual his genes close to trp genes. Analysis of these deletions shows that the histidine operon on the prophage is oriented clockwise as on the bacterial chromosome, thus opposite to the orientation of the trp operon. The presence of the his promoter-operator region is inferred by the ability of the prophage-carrying strain to derepress sequentially under conditions in which the histidine concentration is limiting. In addition to his, the gnd gene is also present on the prophage and is located between his and trp operons. The bacterial genes are inserted in the right arm of the prophage and substitute for all of the late function genes, except for the first three. These data indicate that the "sense" strand for transcription of the his operon in vivo must be the "R" strand.


Assuntos
Mapeamento Cromossômico , Colífagos/metabolismo , Escherichia coli/metabolismo , Ligação Genética , Histidina/metabolismo , Óperon , Transdução Genética , Cromossomos Bacterianos , Genótipo , Mutação , Salmonella typhimurium/enzimologia , Fatores de Tempo
20.
Proc Natl Acad Sci U S A ; 70(9): 2692-6, 1973 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-4582195

RESUMO

An in vitro system was developed for transcription of the histidine operon of Esherichia coli carried in the genome of a defective varphi80 transducing phage. The messenger RNA (mRNA) of the histidine operon synthesized in the in vitro system was detected by hybridization to single strands of both varphi80 and varphi80dhis DNA, and by competition of this hybridization with unlabeled histidine mRNA that had been synthesized in vivo (RNA extracted from cells in which the histidine operon had been derepressed). Under the conditions used, RNA complementary to the histidine operon was about 15% of the total RNA that was synthesized in vitro from the varphi80dhis DNA template. The RNA complementary to the histidine operon was synthesized on the "sense" strand (the R strand) of varphi80dhis in the form of a polycistronic message with a sedimentation coefficient (about 38 S) very close to that observed for the histidine mRNA synthesized in vivo. Synthesis of the histidine operon RNA appears to be subject to control in vitro. Addition of the first enzyme of the pathway for histidine biosynthesis blocked transcription of the histidine operon specifically, strongly suggesting that this enzyme acts as a regulatory protein for the histidine operon.


Assuntos
Colífagos/metabolismo , Histidina/biossíntese , Óperon , Pentosiltransferases/metabolismo , RNA Mensageiro/biossíntese , Transcrição Gênica , Sistema Livre de Células , Centrifugação com Gradiente de Concentração , Mapeamento Cromossômico , DNA Viral , Escherichia coli/metabolismo , Retroalimentação , Hibridização de Ácido Nucleico , RNA/análise , RNA/biossíntese , RNA Mensageiro/análise , Moldes Genéticos , Trítio
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