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1.
Climacteric ; 23(4): 330-335, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32648827

RESUMO

Endometrial cancer is the most common gynecological malignancy with a relatively good overall prognosis. It traditionally has two subtypes: type 1 (endometrioid carcinoma) and type 2 (non-endometrioid carcinoma). The prognosis is excellent for stage I endometrioid cancer, with a 5-year survival rate of 96%. However, the prognosis is much worse for women with high-risk endometrial cancer. Effective preoperative staging is important in order to tailor treatment and achieve optimal long-term survival. The majority of asymptomatic polyps detected by ultrasound are treated surgically. Conventionally, dilatation and curettage was performed to obtain a histological diagnosis, but nowadays hysteroscopy with biopsy is starting to be considered as the gold standard. Hysteroscopic resection seems to reduce the risk of underdiagnosed (atypical endometrial hyperplasia) endometrial cancer. To avoid the spread of malignant cells, hysteroscopy should be performed with concern to keep intrauterine pressure low. In comparison with cervical injection, the hysteroscopic method has a better detection rate in the para-aortic area during sentinel lymph node mapping. In the assessment of cervical involvement, the accuracy of magnetic resonance imaging is significantly higher than the accuracy of hysteroscopy. In fertility-sparing cases, hysteroscopic endometrium resection with progesterone therapy is an acceptable option.


Assuntos
Neoplasias do Endométrio/cirurgia , Endométrio/cirurgia , Histeroscopia/métodos , Colo do Útero/cirurgia , Feminino , Humanos
2.
Climacteric ; 23(4): 325-329, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32648828

RESUMO

Introduction: Most endometrial polyps represent focal hyperplasia of the endometrium. Endometrial polyps can be diagnosed by ultrasound, hysterocontrast sonography, hysterosalpingography, endometrial biopsy, and uterine curettage, but diagnostic hysteroscopy is considered the gold-standard method, with the greatest sensitivity and specificity and also with the opportunity for treatment at the same time.Study design: A retrospective study was conducted on 424 patients between 2006 and 2018. The polyps were verified during diagnostic hysteroscopy and were removed by resectoscopy or curettage. All samples underwent histological examination. The effectivity of the type of resection and the recurrence rate were evaluated.Results: The average age of the patients was 60.2 ± 9.3 years. Polyps were excised in 62.97% by resectoscopic polypectomy and in 37.03% by curettage. Malignancy was confirmed in 4.24% of cases. Histological verification of polyps was 79.4% in the resectoscopy group and 69.04% in the curettage group; the difference was significant (p < 0.01). The recurrence rate was 20.47% after resectoscopy and 27.12% following curettage.Conclusion: Hysteroscopy remains the best option and the gold-standard method among diagnostic procedures of endometrial pathology. In this study, there was a significant difference in matching hysteroscopic and histological findings in the two methods of polypectomy. The recurrence rate is also lower following resectoscopy.


Assuntos
Curetagem/métodos , Neoplasias do Endométrio/cirurgia , Histeroscopia/métodos , Recidiva Local de Neoplasia/epidemiologia , Pólipos/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/patologia , Endométrio/patologia , Endométrio/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Pólipos/patologia , Pós-Menopausa , Período Pós-Operatório , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do Tratamento
3.
Urol Ann ; 14(1): 102-104, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35197714

RESUMO

Vesicovaginal fistula (VVF) is the most common genitourinary fistula associated with significant, detrimental impact on the quality of life. Surgical repair of VVF may be complex requiring tissue interposition techniques to bring fresh blood supply, minimize recurrence, and improve functional outcomes. The international literature is scarce regarding complications related to interposition tissue. However, caution is particularly recommended in selecting the tissue interposition technique to avoid unexpected and frustrating problems. We present a 57-year-old woman following multiple failed transvaginal and transabdominal VVF repairs involving a labium majus skin island flap (Lehoczky flap) after radical hysterectomy for cervical cancer.

4.
J Seismol ; 26(4): 653-685, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35313617

RESUMO

The single-station microtremor horizontal-to-vertical spectral ratio (MHVSR) method was initially proposed to retrieve the site amplification function and its resonance frequencies produced by unconsolidated sediments overlying high-velocity bedrock. Presently, MHVSR measurements are predominantly conducted to obtain an estimate of the fundamental site frequency at sites where a strong subsurface impedance contrast exists. Of the earthquake site characterization methods presented in this special issue, the MHVSR method is the furthest behind in terms of consensus towards standardized guidelines and commercial use. The greatest challenges to an international standardization of MHVSR acquisition and analysis are (1) the what - the underlying composition of the microtremor wavefield is site-dependent, and thus, the appropriate theoretical (forward) model for inversion is still debated; and (2) the how - many factors and options are involved in the data acquisition, processing, and interpretation stages. This paper reviews briefly a historical development of the MHVSR technique and the physical basis of an MHVSR (the what). We then summarize recommendations for MHVSR acquisition and analysis (the how). Specific sections address MHVSR interpretation and uncertainty assessment.

5.
J Magn Magn Mater ; 322(24): L69-L72, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21655331

RESUMO

We report integration of an InAs quantum well micro-Hall magnetic sensor with microfluidics and real-time detection of moving superparamagnetic beads. Beads moving within and around the Hall cross area result in positive and negative Hall voltage signals respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the shape of the dynamic signal.

6.
Science ; 262(5137): 1249-52, 1993 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-17772647

RESUMO

A combination of chemical vapor deposition and scanning tunneling microscopy techniques have been used to produce nanometer-scale, iron-containing deposits with high aspect ratios from an iron pentacarbonyl precursor both on a substrate and on the tunneling tip itself. The structure and composition of the resulting nanodeposits were determined by transmission electron microscopy and high spatial resolution Auger electron spectroscopy. Either polycrystalline, relatively pure, body-centered-cubic iron or disordered carbon-rich material can be deposited, depending on the bias conditions of the tip sample junction and the precursor pressure. Two mechanisms of decomposition are inferred from the growth phenomenology.

7.
Science ; 294(5546): 1488-95, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11711666

RESUMO

This review describes a new paradigm of electronics based on the spin degree of freedom of the electron. Either adding the spin degree of freedom to conventional charge-based electronic devices or using the spin alone has the potential advantages of nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices. To successfully incorporate spins into existing semiconductor technology, one has to resolve technical issues such as efficient injection, transport, control and manipulation, and detection of spin polarization as well as spin-polarized currents. Recent advances in new materials engineering hold the promise of realizing spintronic devices in the near future. We review the current state of the spin-based devices, efforts in new materials fabrication, issues in spin transport, and optical spin manipulation.

8.
J Hosp Infect ; 103(2): 165-169, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31039380

RESUMO

Several Romanian hospitals have noted increasing isolation of Providencia stuartii strains in recent years, with an alarming rate of carbapenem resistance. In order to provide molecular epidemiological data regarding their dissemination, 77 P. stuartii strains collected from five hospitals located in different regions of Romania were analysed. All strains harboured IncA/C plasmid, and 67 carried the blaNDM-1 gene. Six clonal clusters were differentiated by pulsed-field gel electrophoresis. The predominant subtype was found in all five hospitals. Our study highlights the need for efficient infection-control measures, the optimization of antibiotic use and the targeted surveillance for carbapenemase-producing P. stuartii.


Assuntos
Infecção Hospitalar/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Providencia/enzimologia , Providencia/isolamento & purificação , beta-Lactamases/genética , Infecção Hospitalar/transmissão , Infecções por Enterobacteriaceae/transmissão , Genótipo , Hospitais , Humanos , Epidemiologia Molecular , Tipagem Molecular , Plasmídeos/análise , Providencia/classificação , Providencia/genética , Romênia/epidemiologia
9.
Biosystems ; 93(3): 211-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18554775

RESUMO

The monitoring and analysis of the processes taking place in an ecosystem is a key issue for a sustainable human activity. A system of populations, as the biotic component of a complex ecosystem is usually affected by the variation of its abiotic environment. Even in nearly natural ecosystems an abiotic effect like climatic implications of global warming may cause important changes in the dynamics of the population system. In ecosystems involving field cultivation or any industrial activity; the abiotic parameter in question may be the concentration of a substance, changing, e.g. as a result of pollution, application of a pesticide, or a fertilizer, etc. In many cases the observation of the densities of each population may be technically complicated or expensive, therefore the question arises whether from the observation of the densities of certain (indicator) populations, the whole state process of the population system can be uniquely recovered. The paper is aimed at a methodological development of the state monitoring, under the conditions of a changing environment. It is shown, how the technique of mathematical systems theory can be applied not only for the approximate calculation of the state process on the basis of the observed data, even under the effect of an exogene abiotic change with known dynamics; but in certain cases, also for the estimation of the unknown biological effect of the change of an abiotic parameter. The proposed methodology is applied to simple illustrative examples concerning a three-species predator-prey system.


Assuntos
Ecossistema , Monitoramento Ambiental , Animais
10.
Biochim Biophys Acta ; 894(2): 327-31, 1987 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-3676301

RESUMO

Both plastocyanin and cytochrome f were purified using a combination of affinity chromatography together with established methods. Plastocyanin was partially purified using the method of Davis and San Pietro (Anal. Biochem. 95 (1979) 254-259), after which it was further purified using a column of cytochrome c covalently attached to Sepharose 4B. The affinity column was prepared using the method of Godinot and Gautheron (Methods Enzymol. 54 (1979) 112-114). The final purity index ratio (A278/A597) was less than 1.2, which is equal to that obtained using the more expensive FPLC procedure (Anderson, G.P., Sanderson, D.G., Lee, C.H., Durell, S., Anderson, L.B. and Gross, E.L. (1987) Biochim. Biophys. Acta 894, issue 3). Cytochrome f was partially purified using a modification of the method of Matazaki et al. (Plant Cell. Physiol. 16 (1975) 237-246) and bound to an affinity column of plastocyanin covalently attached to Sepharose 4B. Cytochrome f purified using this procedure had a purity index ratio (A554.5/A277) of 1.2. Both proteins are tyrosine proteins containing no tryptophan residues. After the affinity chromatography step, the fluorescence emission spectrum of either plastocyanin or cytochrome f was typical of a tyrosine protein free from tryptophan contamination.


Assuntos
Citocromos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Plastocianina/isolamento & purificação , Cromatografia de Afinidade , Citocromos f , Espectrometria de Fluorescência
11.
J Thromb Haemost ; 13(6): 1010-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25851122

RESUMO

BACKGROUND: Recommendations for management of cancer-related venous thromboembolism (VTE) in patients already receiving anticoagulant therapy are based on low-quality evidence. This international registry sought to provide more information on outcomes after a breakthrough VTE in relation to anticoagulation strategies. METHODS: Patients with cancer and VTE despite anticoagulant therapy were reported to the registry. Data on treatments, VTE events, major bleeding, residual thrombosis symptoms and death were collected for the following 3 months. Breakthrough VTE and subsequent recurrences were objectively verified. Outcomes with different treatment strategies were compared with Cox proportional hazards regression. RESULTS: We registered 212 patients with breakthrough VTE. Of those, 59% had adenocarcinoma and 73% had known metastases. At the time of the breakthrough event, 70% were on low-molecular-weight heparin (LMWH) and 27% on a vitamin K antagonist (VKA); 70% had a therapeutic or supratherapeutic dose. After breakthrough the regimen was: unchanged therapeutic dose in 33%, dose increased in 31%, switched to another drug in 24%; and other management in 11%. During the following 3 months 11% had another VTE, 8% had major bleeding and 27% died. Of the survivors, 74% had residual thrombosis symptoms. Additional VTE recurrence was less common with LMWH than with a VKA (hazard ratio [HR], 0.28; 95% confidence interval [CI], 0.11-0.70) but similar with unchanged or increased anticoagulant intensity (HR, 1.09; 95% CI, 0.45-2.63). The bleeding rate did not increase significantly with dose escalation. CONCLUSION: Morbidity and mortality are high after recurrence of cancer-related VTE despite anticoagulation. Further treatment appears to be more effective with LMWH than with a VKA.


Assuntos
Anticoagulantes/administração & dosagem , Heparina de Baixo Peso Molecular/administração & dosagem , Neoplasias/complicações , Tromboembolia Venosa/tratamento farmacológico , Varfarina/administração & dosagem , Idoso , Anticoagulantes/efeitos adversos , Distribuição de Qui-Quadrado , Substituição de Medicamentos , Feminino , Hemorragia/induzido quimicamente , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/mortalidade , Neoplasias/patologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Tromboembolia Venosa/sangue , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/mortalidade , Vitamina K/antagonistas & inibidores , Varfarina/efeitos adversos
12.
Am J Clin Nutr ; 74(3): 364-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11522561

RESUMO

BACKGROUND: Previous studies showed significant inverse correlations between values of trans isomeric and long-chain polyunsaturated fatty acids in plasma lipids of preterm infants and healthy children aged 1-15 y. OBJECTIVE: We sought to evaluate the same correlations in full-term infants at birth. DESIGN: We studied healthy full-term infants (n = 42) born after normal pregnancies and deliveries. All infants had a family history of atopy (both parents or one of the parents and a sibling had atopic symptoms). The fatty acid composition of venous cord blood lipids was determined by high-resolution capillary gas-liquid chromatography. RESULTS: The mean (+/-SEM) sum of trans fatty acids was 0.49 +/- 0.02% by wt in phospholipids, 2.47 +/- 0.20% by wt in cholesterol esters, 1.73 +/- 0.09% by wt in triacylglycerols, and 1.59 +/- 0.07% by wt in nonesterified fatty acids. Linear correlation analysis showed significant inverse correlations between the sum of trans fatty acids and both arachidonic acid and docosahexaenoic acid in phospholipids (r = -0.56, P < 0.001, and r = -0.48, P = 0.01, respectively), cholesterol esters (r = -0.52, P < 0.001, and r = -0.39, P = 0.018, respectively), and nonesterified fatty acids (r = -0.41, P = 0.007, and r = -0.41, P = 0.006, respectively). CONCLUSION: Because trans fatty acids in the fetal circulation must originate from the maternal diet, our results indicate that maternal exposure to trans fatty acids may represent a previously neglected variable that inversely influences long-chain polyunsaturated fatty acid status in full-term infants at birth.


Assuntos
Ácidos Graxos Insaturados/sangue , Sangue Fetal/química , Feto/metabolismo , Ésteres do Colesterol/sangue , Ésteres do Colesterol/química , Cromatografia Gasosa , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6 , Ácidos Graxos Insaturados/metabolismo , Feminino , Humanos , Recém-Nascido , Isomerismo , Masculino , Troca Materno-Fetal , Fenômenos Fisiológicos da Nutrição , Fosfolipídeos/sangue , Fosfolipídeos/química , Gravidez , Triglicerídeos/sangue , Triglicerídeos/química
13.
Neurology ; 55(4): 544-8, 2000 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-10953189

RESUMO

OBJECTIVE: To investigate cerebral metabolism by 2-[18F]fluorodeoxy-d-glucose (FDG) uptake using PET and cerebrovascular reverse capacity by transcranial Doppler sonography (TCD) in different mitochondrial diseases (mitochondrial myopathy; mitochondrial encephalopathy, lactacidosis, and stroke-like episodes [MELAS]; and chronic external ophthalmoplegia). BACKGROUND: Previous studies on individual patients with mitochondriopathies revealed abnormal accumulations of mitochondria in endothelium, smooth muscle cells, and pericytes of blood vessels in different parts of the nervous system (cerebrum, cerebellum, sural nerve) and skeletal muscle. On this basis, some investigators suggested a pathogenic role of vascular involvement in the MELAS syndrome and other encephalopathies. smhd1 DESIGN/METHODS: The authors investigated neuronal metabolism and cerebrovascular involvement with PET in 5 cases and with TCD with acetazolamide stimulation in 15 cases. The patients were divided into three groups: 1) interictal MELAS (n = 4); 2) progressive external ophthalmoplegia (n = 6); and 3) pure mitochondrial myopathy and neuropathy (n = 5). The results were compared with those from matched normal control subjects. The diagnoses were based on clinical phenotype as well as histopathologic and molecular analysis. RESULTS: Cerebral glucose uptake was impaired in all patients, both with and without CNS symptoms, particularly in the occipital and temporal lobes. The vasoreactivity of the small arterioles to acetazolamide did not differ significantly between the patients and healthy control subjects or between the different groups of mitochondrial disorders. CONCLUSIONS: MELAS does not appear to be a functional disturbance of arterioles leading to an ischemic vascular event. The clinical symptoms in MELAS are not the result of a mitochondrial angiopathy but are the consequences of a mitochondrial cytopathy affecting neurons or glia. There is no correlation between the decreased glucose metabolism and the duration of the disease.


Assuntos
Circulação Cerebrovascular , Glucose/metabolismo , Miopatias Mitocondriais/metabolismo , Acetazolamida , Acidose Láctica/diagnóstico por imagem , Acidose Láctica/metabolismo , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Inibidores da Anidrase Carbônica , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Síndrome MELAS/diagnóstico por imagem , Síndrome MELAS/metabolismo , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/fisiologia , Encefalomiopatias Mitocondriais/diagnóstico por imagem , Encefalomiopatias Mitocondriais/metabolismo , Miopatias Mitocondriais/diagnóstico por imagem , Oftalmoplegia Externa Progressiva Crônica/diagnóstico por imagem , Oftalmoplegia Externa Progressiva Crônica/metabolismo , Tomografia Computadorizada de Emissão , Ultrassonografia Doppler Transcraniana
14.
Phys Rev Lett ; 84(19): 4485-8, 2000 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-10990717

RESUMO

Giant random telegraph noise (RTN) in the resistance fluctuation of a macroscopic film of perovskite-type manganese oxide La(2/3)Ca(1/3)MnO3 has been observed at various temperatures ranging from 4 to 170 K, well below the Curie temperature ( T(C) approximately 210 K). The amplitudes of the two-level fluctuations vary from 0.01% to 0.2%. We discuss the origin of the RTN to be a dynamic mixed-phase percolative conduction process, where manganese clusters switch back and forth between two phases that differ in their conductivity and magnetization.

15.
Bone Marrow Transplant ; 14(5): 779-82, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7534161

RESUMO

Recombinant granulocyte colony-stimulating factor (rhG-CSF) has been shown to hasten granulocyte recovery after autologous BMT. In current protocols, rhG-CSF treatment starts 1 day after BM reinfusion. Our study retrospectively examined the effects on haematological recovery of a day 6 delayed administration. Seventy-eight patients receiving autologous BMT for malignant lymphoma (21 non-Hodgkin's lymphoma and 9 Hodgkin's disease) or solid tumors (33 breast carcinoma and 5 ovarian carcinoma) were split up into three study groups. Two groups receiving a 5 micrograms/kg/day of rhG-CSF starting either 1 day (day +1 group, n = 25 patients) or 6 days (day +6 group, n = 24 patients) after BM reinfusion were compared with 29 historical control patients. Granulocyte recovery to 0.5 x 10(9)/l was 12 days in day +6 and day +1 groups versus 16 days in control group (p < 0.005) without any difference in other hematological parameters, infectious complications or length of hospitalisation between the three groups. The day +6 administration allows elimination of a median of 7 days rhG-CSF. It has been concluded that the day +6 administration gives the same clinical benefit as day +1 administration with consequent cost reductions.


Assuntos
Transplante de Medula Óssea/métodos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Granulócitos/efeitos dos fármacos , Adulto , Bacteriemia/etiologia , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/patologia , Neoplasias da Mama/sangue , Neoplasias da Mama/terapia , Esquema de Medicação , Feminino , Granulócitos/patologia , Hematopoese/efeitos dos fármacos , Doença de Hodgkin/sangue , Doença de Hodgkin/terapia , Humanos , Contagem de Leucócitos , Linfoma não Hodgkin/sangue , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/terapia , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Transplante Autólogo
16.
J Dent Res ; 58(7): 1735-9, 1979 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-109482

RESUMO

Since we have found that conventional methods of dentin apposition measurements are inaccurate, we have devised a three dimensional model. This model allows the investigator to measure dentin apposition volumetrically, and simultaneously consider odontoblast activity and the geometric relationships which influence the configuration of the dentin.


Assuntos
Dentina/anatomia & histologia , Dentinogênese , Modelos Anatômicos , Modelos Biológicos , Modelos Estruturais , Animais , Contagem de Células , Haplorrinos , Macaca mulatta , Odontoblastos/citologia , Odontoblastos/fisiologia , Fatores de Tempo
17.
J Dent Res ; 62(5): 562-5, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6573372

RESUMO

Most reports of Aboriginal tooth wear have been descriptive, and few have dealt with the question of wear rate. This study records cusp heights of dental casts taken from individuals during a growth study of Aboriginal children from ages six to 18. Their rates of wear were greater than those of Europeans, and the most rapid rate was recorded among Aboriginal males. These differences are due to the quantity of dietary abrasives.


Assuntos
Havaiano Nativo ou Outro Ilhéu do Pacífico , Abrasão Dentária/fisiopatologia , Adolescente , Adulto , Fatores Etários , Austrália , Criança , Feminino , Humanos , Masculino , Modelos Dentários , Odontometria , Abrasão Dentária/patologia
18.
Mutat Res ; 41(2-3): 361-76, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-796722

RESUMO

Reversion of the mammalian temperature sensitive leucyl-tRNA synthetase mutant CHO tsH1 [33] has been investigated to determine its potential for mutagenesis studies. The protocol for a mutation assay using the new class of temperature sensitive conditional lethal mutants of somatic cells is presented. While it requires careful control of temperature during revertent selection it promises to provide a system complementary to the existing mutation assays. UV and EMS mutagenesis of tsH1 has confirmed that approx. 3TD of expression time are sufficient for complete expression of induced mutants at low mutagen doses (80% survival following UV and 40-50% with EMS). At a higher UV dose resulting in only 10% survival much longer expression times were required which cannot be explained by growth delays alone. While the reason for this is unknown it suggests that care must be taken in studies which require high mutagen doses. Representative revertants which were isolated show a range of phenotypes between those of tsH1 and WT. They appear to be a promising source of extragenic suppressor mutants [33] with alterations in functions affecting protein synthesis.


Assuntos
Aminoacil-tRNA Sintetases/biossíntese , Técnicas Genéticas , Leucina-tRNA Ligase/biossíntese , Mutação , Linhagem Celular , Relação Dose-Resposta a Droga , Metanossulfonato de Etila/farmacologia , Genes Letais , Temperatura Alta , Temperatura , Raios Ultravioleta
19.
Arch Oral Biol ; 33(12): 901-6, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3256297

RESUMO

The ability to describe dental arch shape is necessary for biomechanical studies of occlusion as well as for anthropological studies of human and primate dental variation. A mathematical method of describing and classifying human dental arch shape was used to assess the nature of individual variability. The method involved the calculation of a series of third-degree polynomials which were fitted to coordinate points along the dental arcade. The slopes of the polynomials, evaluated at these coordinate points, provided a multivariate description of shape, independent of arch size. Graphic representations of arch shape could be constructed from the polynomial equations. These mathematical techniques were used in association with multivariate and univariate statistics to explore the types of variability in dental arch shape among a population of Australian aborigines. The results illustrated the ambiguities of conventional subjective classifications.


Assuntos
Arco Dental/anatomia & histologia , Havaiano Nativo ou Outro Ilhéu do Pacífico , Adulto , Antropometria , Austrália , Humanos , Matemática
20.
Lipids ; 35(11): 1179-84, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11132177

RESUMO

Previously we reported significantly higher values of gamma-linolenic acid (GLA, 18:3n-6), dihomo-gamma-linolenic acid (DHGLA, 20:3n-6), and arachidonic acid (20:4n-6) in plasma lipid classes in obese children than in nonobese controls. In the present study, fatty acid composition of plasma phospholipids (PL) and sterol esters (STE) was determined by high-resolution capillary gas-liquid chromatography in obese children with and without metabolic cardiovascular syndrome [MCS: defined as simultaneous presence of (i) dyslipidemia, (ii) hyperinsulinemia, (iii) hypertension, and.(iv) impaired glucose tolerance] and in nonobese controls. Fatty acid composition of PL and STE lipids did not differ between obese children without MCS and controls. Obese children with MCS exhibited significantly lower linoleic acid (LA, 18:2n-6) values in PL (17.43 [2.36], % wt/wt, median [range from the first to the third quartile]) than obese children without MCS (19.14 [3.49]) and controls (20.28 13.80]). In contrast, PL GLA values were significantly higher in obese children with (0.13 [0.08]) than in those without MCS (0.08 [0.04]), whereas STE GLA values were higher in obese children with MCS (1.04 [0.72]) than in controls (0.62 [0.48]). DHGLA values in PL were significantly higher in obese children with MCS (4.06 [0.74]) than in controls (2.69 [1.60]). The GLA/LA ratio was significantly higher, whereas the AA/DHGLA ratio was significantly lower in obese children with MCS than in obese children without MCS and in controls. In this study, LA metabolism was affected only in obese children with but not in those without MCS. In obese children with MCS, delta6-desaturase activity appeared to be stimulated, whereas delta5-desaturase activity appeared to be inhibited. Disturbances in LA metabolism may represent an additional health hazard within the multifaceted clinical picture of MCS.


Assuntos
Ácidos Graxos Insaturados/sangue , Lipídeos/sangue , Angina Microvascular/sangue , Obesidade/sangue , Adolescente , Estudos de Casos e Controles , Criança , Cromatografia Gasosa , Feminino , Humanos , Lipídeos/química , Masculino
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