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1.
Phys Rev Lett ; 126(15): 152701, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929230

RESUMO

The discrepancy between observations from γ-ray astronomy of the ^{60}Fe/^{26}Al γ-ray flux ratio and recent calculations is an unresolved puzzle in nuclear astrophysics. The stellar ß-decay rate of ^{59}Fe is one of the major nuclear uncertainties impeding us from a precise prediction. The important Gamow-Teller strengths from the low-lying states in ^{59}Fe to the ^{59}Co ground state are measured for the first time using the exclusive measurement of the ^{59}Co(t,^{3}He+γ)^{59}Fe charge-exchange reaction. The new stellar decay rate of ^{59}Fe is a factor of 3.5±1.1 larger than the currently adopted rate at T=1.2 GK. Stellar evolution calculations show that the ^{60}Fe production yield of an 18 solar mass star is decreased significantly by 40% when using the new rate. Our result eliminates one of the major nuclear uncertainties in the predicted yield of ^{60}Fe and alleviates the existing discrepancy of the ^{60}Fe/^{26}Al ratio.

2.
Phys Rev Lett ; 124(15): 152502, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32357034

RESUMO

Detailed spectroscopy of the neutron-unbound nucleus ^{28}F has been performed for the first time following proton/neutron removal from ^{29}Ne/^{29}F beams at energies around 230 MeV/nucleon. The invariant-mass spectra were reconstructed for both the ^{27}F^{(*)}+n and ^{26}F^{(*)}+2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the ^{28}F ground state, with S_{n}(^{28}F)=-199(6) keV, while analysis of the 2n decay channel allowed a considerably improved S_{n}(^{27}F)=1620(60) keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of ^{28}F. Importantly, in the case of the ground state, the reconstructed ^{27}F+n momentum distribution following neutron removal from ^{29}F indicates that it arises mainly from the 1p_{3/2} neutron intruder configuration. This demonstrates that the island of inversion around N=20 includes ^{28}F, and most probably ^{29}F, and suggests that ^{28}O is not doubly magic.

3.
Phys Rev Lett ; 120(15): 152504, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756867

RESUMO

The emission of neutron pairs from the neutron-rich N=12 isotones ^{18}C and ^{20}O has been studied by high-energy nucleon knockout from ^{19}N and ^{21}O secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay ^{19}N(-1p)^{18}C^{*}→^{16}C+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a ^{14}C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay ^{21}O(-1n)^{20}O^{*}→^{18}O+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the ^{16}O core and reduces the number of pairs.

4.
J Chem Phys ; 148(13): 134701, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626883

RESUMO

We experimentally determine the effective nonlinear second-order susceptibility of gold over the visible spectral range. To reach that goal, we probe by vibrational two-color sum-frequency generation spectroscopy the methyl stretching region of a dodecanethiol self-assembled monolayer adsorbed on a gold film. The sum-frequency generation spectra show a remarkable shape reversal when the visible probe wavelength is tuned from 435 to 705 nm. After correcting from Fresnel effects, the methyl stretching vibrations serve as an internal reference, allowing to extract the dispersion of the absolute phase and relative amplitude of the effective nonlinear optical response of gold in the visible range.

6.
Ceska Gynekol ; 77(2): 118-26, 2012 Apr.
Artigo em Tcheco | MEDLINE | ID: mdl-22702068

RESUMO

OBJECTIVE: Presentation of clinical results and experience with this technique during past six years. DESIGN: Original paper. SETTINGS: Gynekologicko-porodnická klinika LF MU a FN Brno, Interní hemato-onkologická klinika LF MU a FN Brno, Department of Obstetrics and Gynecology. Hadassah University Hospital Ein-Karem, Jerusalem, Izrael. INTRODUCTION: Ovarian tissue cryopreservation (OTC) and its future auto-transplantation becomes an alternative for patients to prevent serious damage of ovarian function by oncology treatment. METHODS: Patient is indicated to OTC in case of high risk of ovarian failure due to planned chemotherapy and impossibility to use other oncofertility techniques. Ovarian tissue harvesting is done by laparoscopy in short-term general anesthesia. After tissue processing the samples are cryopreserved in programmable automatic freezer or by vitrification. The auto-transplantation of ovarian tissue is planned after the complete cure of patient's malignancy. Our workplace doesn't have own experience with tissue transplantation - until now cryopreserved tissue has not yet been utilized by the patients. Clinical experience with this technique gained by our team during academic stay in abroad Israeli clinic is presented. RESULTS: During the years of 2005-2011 the OTC was performed in 19 cancer patients before chemotherapy. In majority of cases, patients suffered from blood or lymph node systemic malignancy (84%). Average age of women was 26 years. The patient set consisted of mostly nulliparous women (88%). Patient's average body mass index was 23,9 kg/m2. The length of systemic chemotherapy averaged 7.1 months. Time from fertility preservation counseling to chemotherapy was not exceeding one week (7.2 days on average). Ovarian tissue harvesting was conducted by laparoscopic surgery in all cases. The length of surgery did not exceed 60 minutes and no surgical complications were observed. The case of ovarian tissue transplantation performed on abroad university settings is discussed. CONCLUSION: In the consensus of with international guidelines OTC is offered to patients with high risk of ovarian failure doe to cytotoxic oncology treatment. Research in the field of oncofertility is focused on the techniques of in-vitro folliculogenesis in retrieved ovarian tissue.


Assuntos
Criopreservação , Preservação da Fertilidade , Neoplasias/tratamento farmacológico , Ovário , Adolescente , Adulto , Feminino , Humanos , Laparoscopia , Coleta de Tecidos e Órgãos/métodos , Adulto Jovem
7.
Reprod Biomed Online ; 20(1): 48-52, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20158987

RESUMO

Whole ovary cryopreservation and transplantation has been proposed as a method for preserving long-term ovarian function. This work reports ovarian function 6years post transplantation of frozen-thawed whole sheep ovaries. Three 9-month-old Assaf sheep underwent unilateral oophorectomy to provide organs for the experiments. After perfusing with cold University of Wisconsin solution supplemented with 10% dimethyl sulphoxide, ovaries were cryopreserved using unidirectional solidification freezing technology. After thawing, ovaries were re-perfused and re-transplanted orthotopically by microvascular re-anastomosis, to the contralateral ovarian pedicle after removing the remaining ovary. Six years following transplantation and after inducing superovulation, the sheep were killed and the ovaries analysed. Two ovaries had normal size and shape showing some recent corpora lutea, while the third showed atrophic changes. A total of 36 antral follicles were counted by transillumination and four germinal vesicle oocytes were aspirated and matured in vitro to metaphase II. Serum progesterone concentrations were indicative of ovulatory activity in one of the three sheep. Histological evaluations revealed normal tissue architecture, intact blood vessels and follicles at various stages. Currently, this is the longest recorded ovarian function after cryopreservation and re-transplantation. Cryopreservation of whole ovaries, using directional freezing combined with microvascular anastomosis, is a promising method for preserving long-term reproductive capacity and endocrine function.


Assuntos
Sobrevivência Celular/fisiologia , Criopreservação/métodos , Ovário/fisiologia , Ovário/transplante , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Feminino , Estudos Longitudinais , Modelos Animais , Oócitos/citologia , Oócitos/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Ovário/citologia , Ovinos , Fatores de Tempo
8.
Ultrasound Obstet Gynecol ; 34(5): 572-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19852046

RESUMO

OBJECTIVES: To compare women undergoing magnetic resonance-guided focused ultrasound (MRgFUS) to a group of contemporaneously recruited women undergoing total abdominal hysterectomy. Patient demographics, safety parameters, quality of life outcomes and disability measures are reported. METHODS: One hundred and nine women were recruited in seven centers for MRgFUS treatment and 83 women who underwent abdominal hysterectomy were recruited in seven separate centers to provide contemporaneous assessment of safety. The adverse-event profile and disability parameters were prospectively assessed. Patients were also screened at baseline and at 1, 3 and 6 months using the SF-36 health survey questionnaire. RESULTS: There were no life-threatening adverse events in either group. Overall, the number of significant clinical complications and adverse events was lower in women in the MRgFUS group compared to women undergoing hysterectomy. MRgFUS was associated with significantly faster recovery, including resumption of usual activities. At 6 months of follow-up, there were four (4%) treatment failures in the MRgFUS arm. Regarding SF-36 subscale scores, at 6 months there was improvement in all SF-36 subscales for both treatment groups. However, most of the SF-36 subscale scores were significantly better at this stage in the hysterectomy group than in the MRgFUS group. Women undergoing MRgFUS had steady improvement in all parameters throughout the 6-month follow-up period, despite the fact that they continued to have myomatous uteri and menstruation, which at baseline had given them significant symptomatology. CONCLUSIONS: The results of this study show that MRgFUS treatment of uterine leiomyomas leads to clinical improvement with fewer significant clinical complications and adverse events compared to hysterectomy at 6 months' follow-up.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Histerectomia/métodos , Leiomioma/terapia , Neoplasias Uterinas/terapia , Adulto , Técnicas de Apoio para a Decisão , Feminino , Humanos , Histerectomia/psicologia , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Imagem por Ressonância Magnética Intervencionista/métodos , Imagem por Ressonância Magnética Intervencionista/psicologia , Pessoa de Meia-Idade , Satisfação do Paciente/estatística & dados numéricos , Qualidade de Vida/psicologia , Resultado do Tratamento , Ultrassonografia , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgia
9.
Neural Netw ; 22(2): 116-25, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19243912

RESUMO

In this article, we present two neural architectures for the control of socially interacting robots. Beginning with a theoretical model of interaction inspired by developmental psychology, biology and physics, we present two sub-cases of the model that can be interpreted as "turn-taking" and "synchrony" at the behavioral level. These neural architectures are both detailed and tested in simulation. A robotic experiment is even presented for the "turn-taking" case. We then discuss the interest of such behaviors for the development of further social abilities in robots.


Assuntos
Redes Neurais de Computação , Robótica/métodos , Comportamento Social , Algoritmos , Inteligência Artificial , Comunicação , Simulação por Computador , Sistemas Computacionais , Biologia do Desenvolvimento , Relações Interpessoais , Modelos Psicológicos
10.
Hum Reprod ; 23(1): 46-53, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17989069

RESUMO

BACKGROUND: Human embryonic stem cells (hESCs) suitable for future transplantation therapy should preferably be developed in an animal-free system. Our objective was to develop a laser-based system for the isolation of the inner cell mass (ICM) that can develop into hESC lines, thereby circumventing immunosurgery that utilizes animal products. METHODS: Hatching was assisted by micromanipulation techniques through a laser-drilled orifice in the zona pellucida of 13 abnormal preimplantation genetic diagnosed blastocysts. ICMs were dissected from the trophectoderm by a laser beam and plated on feeders to derive hESC lines. RESULTS: eight ICMs were isolated from nine hatched blastocysts and gave rise to three hESC lines affected by myotonic dystrophy type 1, hemophilia A and a carrier of cystic fibrosis 405 + 1G > A mutation. Five blastocysts that collapsed during assisted hatching or ICM dissection were plated whole, giving rise to an additional line affected by fragile X. All cell lines expressed markers of pluripotent stem cells and differentiated in vitro and in vivo into the three germ layers. CONCLUSIONS: These hESC lines can serve as an important model of the genetic disorders that they carry. Laser-assisted isolation of the ICMs may be applied for the derivation of new hESC lines in a xeno-free system for future clinical applications.


Assuntos
Linhagem Celular , Dissecação/métodos , Embrião de Mamíferos/patologia , Células-Tronco Embrionárias/patologia , Fertilização in vitro , Lasers , Diagnóstico Pré-Implantação , Biomarcadores/metabolismo , Massa Celular Interna do Blastocisto/patologia , Diferenciação Celular , Separação Celular , Fibrose Cística/diagnóstico , Fibrose Cística/embriologia , Fibrose Cística/genética , Fibrose Cística/patologia , Células-Tronco Embrionárias/metabolismo , Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/embriologia , Síndrome do Cromossomo X Frágil/patologia , Hemofilia A/diagnóstico , Hemofilia A/embriologia , Hemofilia A/patologia , Heterozigoto , Humanos , Distrofia Miotônica/diagnóstico , Distrofia Miotônica/embriologia , Distrofia Miotônica/patologia , Células-Tronco Pluripotentes/metabolismo
11.
Rev Sci Instrum ; 89(5): 052001, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29864857

RESUMO

Particle-in-cell (PIC) codes are used since the early 1960s for calculating self-consistently the motion of charged particles in plasmas, taking into account external electric and magnetic fields as well as the fields created by the particles itself. Due to the used very small time steps (in the order of the inverse plasma frequency) and mesh size, the computational requirements can be very high and they drastically increase with increasing plasma density and size of the calculation domain. Thus, usually small computational domains and/or reduced dimensionality are used. In the last years, the available central processing unit (CPU) power strongly increased. Together with a massive parallelization of the codes, it is now possible to describe in 3D the extraction of charged particles from a plasma, using calculation domains with an edge length of several centimeters, consisting of one extraction aperture, the plasma in direct vicinity of the aperture, and a part of the extraction system. Large negative hydrogen or deuterium ion sources are essential parts of the neutral beam injection (NBI) system in future fusion devices like the international fusion experiment ITER and the demonstration reactor (DEMO). For ITER NBI RF driven sources with a source area of 0.9 × 1.9 m2 and 1280 extraction apertures will be used. The extraction of negative ions is accompanied by the co-extraction of electrons which are deflected onto an electron dump. Typically, the maximum negative extracted ion current is limited by the amount and the temporal instability of the co-extracted electrons, especially for operation in deuterium. Different PIC codes are available for the extraction region of large driven negative ion sources for fusion. Additionally, some effort is ongoing in developing codes that describe in a simplified manner (coarser mesh or reduced dimensionality) the plasma of the whole ion source. The presentation first gives a brief overview of the current status of the ion source development for ITER NBI and of the PIC method. Different PIC codes for the extraction region are introduced as well as the coupling to codes describing the whole source (PIC codes or fluid codes). Presented and discussed are different physical and numerical aspects of applying PIC codes to negative hydrogen ion sources for fusion as well as selected code results. The main focus of future calculations will be the meniscus formation and identifying measures for reducing the co-extracted electrons, in particular for deuterium operation. The recent results of the 3D PIC code ONIX (calculation domain: one extraction aperture and its vicinity) for the ITER prototype source (1/8 size of the ITER NBI source) are presented.

12.
Obstet Gynecol ; 83(4): 605-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8134074

RESUMO

OBJECTIVE: To study the long-term ovarian neoplastic consequences of resection of a dermoid cyst. METHODS: The study population comprised 99 patients who were operated on for an ovarian dermoid cyst. Follow-up information was obtained for 91 women for a mean period of 5.06 +/- 2.46 years. RESULTS: Of the 99 women, 18 had bilateral dermoid cysts. Multiple dermoid cysts in a single ovary were found in nine of the women with bilateral cysts and in one of the remaining patients. Two patients developed malignant germ cell tumors, and three developed a recurrent dermoid cyst in an ovary from which a dermoid cyst had previously been extracted. Bilateral or multiple ovarian dermoid cysts were present at the initial operation in four (80%) of these patients. CONCLUSIONS: Women with bilateral or multiple dermoid cysts may include a subgroup of patients with a greater tendency to develop future ovarian germ cell neoplasms.


Assuntos
Cisto Dermoide/cirurgia , Germinoma/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/cirurgia , Adulto , Cisto Dermoide/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Ovarianas/patologia , Fatores de Tempo
13.
Obstet Gynecol ; 81(1): 112-4, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8416443

RESUMO

OBJECTIVE: To investigate the possible role of position of the intrauterine device (IUD) in accidental pregnancies. METHODS: We examined the location of the IUD in 97 normal women 45-60 days post-insertion, and in 25 pregnant women with the device in situ. RESULTS: A cervically located IUD was identified in seven of 97 women (7.2%) after insertion and in 13 of 25 pregnant women (52%) with the device in situ. The odds ratio for a woman with an intracervical IUD to be pregnant compared with a woman with an IUD in the uterus was 13.93 (95% confidence limits 4.13-48.96). Sonographic follow-up of the pregnant women revealed no change in IUD location during early gestation. CONCLUSIONS: We suggest that cases of failed contraceptive action of the IUD may be secondary to a malpositioned device. A sonographic survey can identify displaced devices. Reinsertion of the IUD in such cases is recommended.


Assuntos
Dispositivos Intrauterinos , Gravidez , Útero/diagnóstico por imagem , Adulto , Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Razão de Chances , Estudos Prospectivos , Ultrassonografia
14.
Fertil Steril ; 71(4): 609-13, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10202867

RESUMO

OBJECTIVE: To present our experience with a flexible and convenient protocol for artificial endometrial preparation without prior GnRH agonist suppression in patients with functioning ovaries undergoing frozen ET. DESIGN: Case series. SETTING: An IVF unit in a university hospital. PATIENT(S): All patients who underwent IVF with embryo cryopreservation from December 1997 to June 1998 and requested transfer of their frozen-thawed embryos. INTERVENTION(S): Controlled endometrial preparation for ET entailed the use of a fixed dose of 6 mg/d of micronized E2 started on day 1 of the cycle, followed by concomitant administration of micronized P placed in the vagina. MAIN OUTCOME MEASURE(S): Hormonal and endometrial profiles throughout the cycle, pregnancy rate per ET, implantation rate, and pregnancy outcome. RESULT(S): Of 185 treatment cycles in 140 patients, 8 cycles (4.3%) were canceled. In another 2 cycles, no embryos were suitable for transfer. For the remaining 175 ET cycles, the calculated pregnancy rate and implantation rate were 21.7% and 9%, respectively. The proliferative phase could be extended up to 20 days but was a mean (+/-SD) of 15+/-1.9 days. CONCLUSION(S): For patients with functioning ovaries, controlled endometrial preparation for the transfer of frozen-thawed embryos can be done successfully by using oral E2 from day 1 of the cycle followed by P preparation. Prior suppression with GnRH agonist is not necessary.


Assuntos
Transferência Embrionária/métodos , Estradiol/administração & dosagem , Ovário/fisiologia , Progesterona/administração & dosagem , Adulto , Criopreservação , Implantação do Embrião , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Vagina/efeitos dos fármacos
15.
Fertil Steril ; 69(6): 1001-4, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9627283

RESUMO

OBJECTIVE(S): To correlate fertilization and clinical pregnancy rates (PRs) in low responders with their E2 levels (<500, 500-800, >800-1,000 pg/mL), age (20-30, 31-40, >40 years), number of follicles, and number of oocytes retrieved. DESIGN: A retrospective study. SETTING: The IVF unit of an academic hospital. PATIENT(S): One hundred forty-three women who failed to attain E2 levels of 1,000 pg/mL on the day of hCG administration. INTERVENTION(S): Controlled ovarian hyperstimulation, blood E2 and progesterone measurements, ultrasonographic scanning of ovarian follicles, oocyte retrieval after hCG administration, and ET. MAIN OUTCOME MEASURE: Clinical PR. RESULT(S): Although E2 levels, fertilization rates, age, and number of oocytes did not differ significantly between the three age groups, the PR achieved in the youngest group was approximately three times as high (19.3%) as that achieved in the two older groups. CONCLUSION: Young low responders represent a unique subset in that their age protects them from the deleterious effects of poor ovarian response.


Assuntos
Envelhecimento/fisiologia , Fertilização in vitro , Ovário/fisiopatologia , Adulto , Envelhecimento/sangue , Estradiol/sangue , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Falha de Tratamento
16.
Fertil Steril ; 66(1): 66-71, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8752613

RESUMO

OBJECTIVE: To assess the potential involvement of cytokines and nitrites in the hyperpermeability characterizing the ovarian hyperstimulation syndrome (OHSS). DESIGN: A controlled clinical study comparing peritoneal fluid (PF) from patients with severe OHSS and from non-OHSS controls. SETTING: Women hospitalized with severe OHSS in three tertiary medical centers. PATIENTS: Twelve patients with severe OHSS necessitating paracentesis and 20 non-OHSS controls. INTERVENTIONS: The criteria for ultrasound-guided paracentesis were tense ascites, hydrothorax, hemoconcentration, or oliguria. MAIN OUTCOME MEASURES: Interleukin (IL) 1 beta IL-1 receptor agonist, IL-2, IL-6, IL-8, and tumor necrosis factor alpha (TNF alpha) levels in PF were assayed by ELISA; nitrites were measured by the "Griess" reaction. Estradiol and P were determined by RIA. RESULTS: Ovarian hyperstimulation syndrome patients had significantly higher PF IL-6 (3,523 versus 30 pg/mL), TNF alpha (14 versus 4.2 pg/mL), and IL-8 (1,695 versus 900 pg/mL). In the serum, only IL-6 levels were significantly higher (375 versus 11 pg/mL). Conversely, nitrite levels were significantly lower in PF of OHSS patients (0.5 versus 34 nmol/mL). Interleukin 1 levels were higher and IL-1 receptor antagonist levels were lower in OHSS patients, suggesting potentially increased biologic potency of IL-1. CONCLUSION: These findings suggest that these substances could be involved in mediating the capillary hyperpermeability characterizing this syndrome.


Assuntos
Líquido Ascítico/metabolismo , Citocinas/metabolismo , Nitritos/metabolismo , Síndrome de Hiperestimulação Ovariana/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucinas/metabolismo , Nitratos/metabolismo
17.
Trans R Soc Trop Med Hyg ; 82(5): 686-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3075353

RESUMO

The dot enzyme-linked immunosorbent assay (dot-ELISA) was compared to the indirect immunofluorescent assay (IIFA) and radioimmunoassay (RIA) for the detection of malaria antibodies. Of 281 sera tested by dot-ELISA, 220 were from Ethiopia, 11 from the Sudan, and 50 from Egypt. A close correlation between the dot-ELISA and RIA results was observed in 92% of the 220 Ethiopian cases. Of the remainder, 6% gave positive RIA and negative dot-ELISA results, and 2% gave positive dot-ELISA and negative RIA results. Antibody titres determined by dot-ELISA and RIA were positively correlated in 10 of the 11 Sudanese cases tested by direct microscopical examination. The eleventh case was positive by dot-ELISA at 1:1000 dilution, but negative by RIA and direct examination. With the 50 Egyptian sera, the dot-ELISA results showed close correspondence to the IIFA results, but the dot-ELISA was 20-40 fold more sensitive than the IIFA. To test specificity, 62 samples from patients with 11 different diseases and conditions were examined by dot-ELISA. No malaria antibodies were detected in any of these or in sera from healthy controls. Dot-ELISA is a potentially useful method for sero-epidemiological studies of malaria.


Assuntos
Anticorpos Antiprotozoários/análise , Ensaio de Imunoadsorção Enzimática , Plasmodium falciparum/imunologia , Animais , Especificidade de Anticorpos , Imunofluorescência , Humanos , Malária/diagnóstico , Radioimunoensaio
18.
Reprod Toxicol ; 15(5): 479-86, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11780955

RESUMO

Benzo(a)pyrene (BaP), an aryl hydrocarbon receptor (AhR) ligand present in cigarette smoke and car exhaust, is thought to have negative effects on male reproduction. We hypothesized that BaP damages sperm through AhR activation, phase I enzyme induction, DNA adduct formation, and increased germ cell apoptosis in the testis, and that resveratrol, a natural competitive inhibitor of the AhR found in some red wines, could prevent the adverse effects of BaP on sperm. Male Balb C mice were injected subcutaneously (s.c.) for 5 weeks with a range of BaP doses (0.5 mg/kg to 50 mg/kg). Live sperm were obtained from the vas deferens, counted, and stained to measure annexin-V positive (apoptotic) cells. In a subsequent study, mice were injected for 5 weeks with corn oil (control), BaP (5 mg/kg/week), or BaP plus resveratrol (50 mg/kg/week) (n = 3 per group). Immunohistochemistry (IHC) was performed on testis sections for the determination of CYP1A1, BaP diol epoxide (BPDE) DNA adducts, and apoptosis and the results quantified by using the HSCORE, a semiquantitative scoring system. Our results demonstrated that sperm counts after 5 weeks were inversely correlated to BaP dosage. BaP (0.5 to 5 mg/week) positively correlated with sperm apoptosis while higher doses increased sperm necrosis. CYP1A1 protein was observed mainly in interstitial cells of some testis sections, but there was no significant induction by BaP. BPDE DNA adducts were induced in all components of the seminiferous tubules by BaP and suppressed by resveratrol: median HSCORE (interquartile range) control 61 (52-71.5); BaP 213 (192-248), P = 0.01 compared to control; BaP plus resveratrol 83 (70-90). BaP significantly increased apoptosis, mainly in spermatogonia: medain HSCORE (interquartile range) BaP 189 (161-223) versus control 83 (57-93), P < 0.01; and this effect was abrogated by resveratrol. Median HSCORE for BaP plus resveratrol was 112 (range 99-121). In summary, BaP caused increased sperm cell BPDE DNA adduct formation and apoptosis in the mouse. The natural AhR antagonist, resveratrol diminished BaP-induced DNA adducts and apoptosis in seminiferous tubules.


Assuntos
Apoptose/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Dano ao DNA/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Espermatozoides/efeitos dos fármacos , Estilbenos/farmacologia , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/metabolismo , Animais , Benzo(a)pireno/metabolismo , Carcinógenos Ambientais/toxicidade , Citoproteção/efeitos dos fármacos , Adutos de DNA/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Resveratrol , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/efeitos dos fármacos , Testículo/enzimologia , Testículo/patologia
19.
Eur J Obstet Gynecol Reprod Biol ; 54(2): 93-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8070605

RESUMO

OBJECTIVE: To study the role of Doppler ultrasound examination in predicting an abnormal perinatal outcome, among post-term pregnancies uncomplicated by an abnormal non-stress test (NST) or reduced amount of amniotic fluid. DESIGN: A prospective study. SETTING: High-risk pregnancy unit, Hadassah Mt. Scopus University Hospital, Jerusalem. SUBJECTS: Seventy-eight women with confirmed gestational age of > 287 days, who had normal initial evaluation and unfavourable cervical examination. INTERVENTIONS: Doppler flow velocity waveforms were recorded from the umbilical and middle cerebral arteries, and from the descending thoracic aorta. MAIN OUTCOME MEASURES: Correlation between Doppler measurements and data regarding delivery. RESULTS: Women who developed signs of fetal distress during labour, or who required intervention because of fetal distress, had elevated umbilical artery systolic/diastolic ratio, decreased middle cerebral artery pulsatility index, and decreased time average aortic blood flow velocity. Umbilical artery Doppler measurements could significantly predict the need for intervention due to fetal distress. CONCLUSIONS: Doppler examination of uncomplicated post-term pregnancies may identify patients with normal results as having a low risk of developing fetal distress during labour. Patients with abnormal Doppler results are prone to need intervention following fetal distress in labour.


Assuntos
Sofrimento Fetal/diagnóstico por imagem , Gravidez Prolongada/fisiologia , Ultrassom , Adulto , Líquido Amniótico/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiologia , Feminino , Feto/irrigação sanguínea , Humanos , Gravidez , Estudos Prospectivos , Fluxo Sanguíneo Regional , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/fisiologia
20.
Chemosphere ; 44(6): 1347-52, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11513111

RESUMO

We evaluated individual adipose tissue (subcutaneous lipomas) dioxin contamination in non-occupationally exposed persons living in France (adult patients undergoing a surgical ablation of benign lipomas), in relation to the corresponding individually evaluated mean daily dietary dioxin intake (DDDI). The diet survey (questionnaire) included information on consumption of meat, fish, milk and dairy products, from which the individual DDDI was calculated. Sixteen subjects participated in this study. DDDI ranged between 1.06 and 3.31 pg I-TEQ/kg body weight, bw (mean value: 2.05+/-0.72). Adipose tissue polychlorinated dibenzo-p-dioxins (PCDD)/polychlorinated dibenzofurans (PCDF) levels ranged between 18.5 and 76.9 pg I-TEQ/g lipids (mean value: 35.6+/-14.8). No relation was found between the DDDI and adipose tissue PCDD/PCDF concentrations. The mean DDDI in France does not fundamentally differ from those found in other industrialised countries, is within the range of 1-4 pg I-TEQ/kg/day recently suggested by WHO-ECEH/ICPS for the tolerable daily intake of dioxins. Adipose tissue PCDD/PCDFs levels are similar to levels in other European countries and USA without relation to sex or age, and can be considered representative European background concentrations. Globalisation of alimentary production leads to a similar food exposure in Western European countries, in spite of dioxins accidental selective contaminations that are epiphenomenon and thus do not have any impact in human dioxin background levels.


Assuntos
Tecido Adiposo/química , Benzofuranos/farmacocinética , Contaminação de Alimentos , Lipoma/química , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/farmacocinética , Poluentes do Solo/farmacocinética , Adulto , Idoso , Benzofuranos/análise , Dibenzofuranos Policlorados , Dieta , Exposição Ambiental , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Dibenzodioxinas Policloradas/análise , Poluentes do Solo/análise
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