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1.
Vascular ; 21(4): 247-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23579380

RESUMO

Carotid artery stenting (CAS) is a validated option in the treatment of selected extracranial carotid artery stenosis. Carotid artery dissection during CAS is a rare but potentially devastating complication. We report a case of acute dissection and thrombosis of the left internal carotid artery during filter tip wire engaging maneuvers, complicated by intraoperative complete blindness of the left eye. Immediate conversion to carotid endarterectomy was performed under general anesthesia with electroencephalographic monitoring. The patient was discharged home symptomless and remains asymptomatic eight months after the operation, with normal left internal carotid patency and fully recovered eyesight. In conclusion, the management of acute carotid occlusion during CAS requires emergent evaluation and definitive endovascular or open surgical repair to minimize neurologic morbidity. We advocate that all endovascular procedures are carried out in a well-established surgical environment.


Assuntos
Dissecação da Artéria Carótida Interna , Stents , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas , Humanos , Trombose
2.
Eur Rev Med Pharmacol Sci ; 16(15): 2082-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23280023

RESUMO

AIM: To evaluate the benefit of endovascular peripheral revascularization on glucose control in patients with chronic limb ischemia. METHODS AND RESULTS: Over a 12 month period, 61 patients (41 male, range 49-88 years of age) presenting with critical limb ischemia (CLI) were treated according to the Trans Atlantic Inter Society Consensus (TASC II) guidelines. After discharge, all patients were asked to measure their glucose level three times daily, and glycated hemoglobin was checked monthly up to 12 months, as well as to fill a questionnaire to assess their Quality of Life (QoL). The revascularization procedure was successful in 90% of cases. Glycemic control and glycated hemoglobin in 22 diabetic patients subgroup were significantly improved after the treatment and remained stable over the follow-up period. There was a significant improvement in QoL that increased steadily from the operation and to reach a plateau after six months. CONCLUSIONS: Peripheral percutaneous angioplasty in subjects with CLI significantly improves glycemic control and ameliorates QoL. Revascularization positively effects also long-term diabetes control as well as QoL.


Assuntos
Angioplastia/métodos , Glicemia/análise , Isquemia/terapia , Extremidade Inferior/irrigação sanguínea , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Isquemia/sangue , Isquemia/psicologia , Masculino , Pessoa de Meia-Idade
3.
J Psychosom Obstet Gynaecol ; 22(2): 83-90, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11446158

RESUMO

The aim of this study was to determine the impact of termination of pregnancy (TOP) on women's sexual well-being, the couple and contraceptive practice. In a prospective qualitative and quantitative study, 103 women undergoing induced abortion by vacuum aspiration were interviewed before the abortion and 6 months later. The interview was performed by means of a questionnaire including open and closed questions, and two psychological tests (Locke-Wallace and Horowitz). After TOP, the majority of women did not report changes in their sexual behavior and satisfaction. Eighteen per cent of women reported a decrease in sexual desire and 17% reported orgasmic disorders. About one-third of women described psychosomatic symptoms, but a minority were traumatized by the event. Ninety-eight per cent of the women were informed about, and had practiced, contraception in the past; 69% had actually used some kind of contraception during the menstrual cycle that had resulted in pregnancy (31% had had unprotected intercourse). Six months later, 83% practiced contraception, and only 17% did not. Fourteen out of 84 couples separated after TOP (one in six). Six months after TOP, the large majority of women interviewed seemed able to cope with TOP. A minority presented some persisting sexual dysfunction and/or some psychosomatic symptoms.


Assuntos
Aborto Induzido/psicologia , Comportamento Contraceptivo/psicologia , Disfunções Sexuais Fisiológicas/etiologia , Parceiros Sexuais/psicologia , Sexualidade/psicologia , Estresse Psicológico/etiologia , Aborto Induzido/efeitos adversos , Feminino , Humanos , Gravidez , Disfunções Sexuais Fisiológicas/psicologia
4.
Eur J Histochem ; 37(2): 155-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7688601

RESUMO

Heterochromatin in mature mouse spermatozoa has been investigated by using C-banding treatment followed by either i) Giemsa staining, ii) staining with DAPI, a fluorochrome specific for AT rich DNA and iii) by using quantitative DNA measurements [Acriflavine-Feulgen, DAPI and Ethidium Bromide (EB)]. We have shown that a fraction of the mature sperm chromatin is affected by C-banding treatment. The sperm chromatin treated with Ba(OH)2 and stained with EB doubled fluorescence emission values found in untreated control preparations. This experimental result clearly shows that the use of intercalating fluorochromes, such as EB, is unsuitable for quantitative evaluation of highly condensed DNAs.


Assuntos
Heterocromatina/ultraestrutura , Espermatozoides/ultraestrutura , Animais , Núcleo Celular/ultraestrutura , Bandeamento Cromossômico , DNA/química , Citometria de Fluxo , Corantes Fluorescentes , Histocitoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coloração e Rotulagem
5.
Minerva Ginecol ; 42(7-8): 289-92, 1990.
Artigo em Italiano | MEDLINE | ID: mdl-1981383

RESUMO

The A. report a cytogenetic study performed on 201 subjects with a defective reproductive fitness. In total, they detected 37 chromosomal changes (18.4%): 7 in 48 subjects (24 couples) with sterility (14.5%), 11 in 96 with hypogonadism and/or criptorchidism (11.4%), 15 in 38 women with oligoamenorrhoea (39.4%) and 4 in 4 patients with Morris syndrome (100%). On the contrary, no chromosomal change was detected in 15 patients with pure gynecomastia. The A. discuss the significance of these chromosomal aberrations, and particularly: the mosaicism XO/XX, because this chromosome picture may be associated with fertility, as in our case; the isodicentric X, because the patient showed the clinical features of the Turner's syndrome; the inv(11), because the patient showed a progressive oligoamenorrhoea, leading us to retain that some chromosome changes, by determining a severe gametic selection, may cause infertility in these subjects. the t(13;14), detected in men with azoospermia, because these changes confirm the presence of a gametic selection, mostly in men. Therefore, according to other reports, the A. suggest that the cytogenetic investigations should be performed in all subjects with abnormal reproductive fitness, for a more accurate diagnostic iter.


Assuntos
Infertilidade Feminina/genética , Infertilidade Masculina/genética , Aberrações dos Cromossomos Sexuais/genética , Adulto , Amenorreia/complicações , Amenorreia/genética , Aberrações Cromossômicas/genética , Criptorquidismo/complicações , Criptorquidismo/genética , Citogenética , Feminino , Humanos , Hipogonadismo/complicações , Hipogonadismo/genética , Infertilidade Feminina/etiologia , Infertilidade Masculina/etiologia , Masculino , Síndrome de Turner/complicações , Síndrome de Turner/genética
6.
Vasc Endovascular Surg ; 45(7): 641-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21984030

RESUMO

PURPOSE: Type A acute aortic dissection is a surgical emergency, and supra-aortic trunk involvement may be complicated by stroke in 6% to 20% of cases. A 66-year-old Caucasian female patient underwent a composite repair of the ascending aorta for type A aortic dissection. Postoperative period was complicated by episodes of "drop attack." Doppler ultrasound of supra-aortic trunks revealed an intimal flap occluding right internal carotid artery. TECHNIQUE: Multiple stenting was performed from carotid bifurcation to internal carotid artery in order to exclude the dissection intimal flap. After endovascular procedure physiatrist considered that motor functional improvement was better than expected, and we support that endovascular resolution of carotid malperfusion led to a better outcome. CONCLUSION: According to other experience, endovascular procedure resulted as a safe and effective way. Moreover, ultrasound monitoring of supra-aortic trunks in postoperative period is recommended.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Lesões das Artérias Carótidas/terapia , Circulação Cerebrovascular , Transtornos Cerebrovasculares/terapia , Procedimentos Endovasculares , Idoso , Dissecção Aórtica/diagnóstico , Aneurisma Aórtico/diagnóstico , Aortografia/métodos , Lesões das Artérias Carótidas/diagnóstico , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/fisiopatologia , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Radiografia Intervencionista , Stents , Síncope/etiologia , Síncope/fisiopatologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler
11.
Hum Reprod ; 8(12): 2167-73, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8150919

RESUMO

Sub-zonal sperm microinjection (SUZI) as a treatment for male factor infertility can facilitate fertilization, however, in many cases oocytes remain unfertilized even though the sperm is placed in close contact with the oolemma. In order to improve our understanding of gamete interaction in cases of failed fertilization, we have analysed the failed fertilized oocytes from both SUZI and conventional in-vitro fertilization. The fluorochrome Hoechst 33342 (which binds specifically to DNA) was used to check for the possible presence of paternal chromatin in the unfertilized oocytes. A significantly higher (P < 0.01) number of microinjected oocytes showed signs of fertilization 2-3 days after sperm microinjection compared to normally inseminated oocytes, 30/175 (17.1%) and 2/79 (2.5%) respectively. In addition, four out of eight couples returning for a second treatment by SUZI displayed anomalies in fertilization in both cycles. The semen characteristics of patients with or without anomalies in fertilization was not different. The irregularities observed in the fertilization process infer that certain male factor patients have intrinsic sperm anomalies lying at the sperm membrane and/or chromatin level that could lead to anomalies in the appearance of the pronuclei.


Assuntos
Fertilização in vitro/métodos , Oócitos/citologia , Interações Espermatozoide-Óvulo/fisiologia , Adulto , Núcleo Celular , Cromatina/metabolismo , Feminino , Humanos , Masculino , Microinjeções , Micromanipulação , Valores de Referência , Zona Pelúcida
12.
J Biosoc Sci ; 26(3): 349-68, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7929483

RESUMO

Onset of capacity for childbearing in women is dated biologically by menarche, although actual onset may be delayed. The end of childbearing is less understood but recent demographic and biological research on fertility at older ages in clarifying the end of fertility. The demographic view of declining fertility with age is based on age-specific fertility in natural fertility populations, artificial insemination and pregnancy rates by age and World Fertility Survey data. New data from the Demographic and Health Surveys on exposure to the risk of pregnancy shows that whereas older women biologically need longer exposure to pregnancy, exposure declines on behavioural grounds such as duration of marriage. Actual fecundity is obscured by factors of fecundability. Recent research on medically assisted conception is adding to the understanding of declining fecundity with age, especially the relative contributions of endometrial and ovarian ageing. This paper reviews the available information on declining fertility with age and discusses the implications of the extension of fertility through new medical technologies.


PIP: This literature review on fecundity and age interactions discusses studies on menopause, on artificial insemination, on sexual behavior, and on assisted reproductive technology. Challenges to the age old notion of biological reproductive declines with age have appeared since the advent of new technologies and the understanding of reproductive potential. With donated oocytes, acyclic women can have a higher probability of conception than young women conceiving naturally. The beginning of childbearing is easily demarcated with the advent of menstrual cycles and fecundity with first ovulation. There are societal constraints on fecundity. Fixing a date on the end of childbearing is not as clear cut. An understanding of the limits of childbearing comes from research on cessation of ovarian follicular function, on natural childbearing populations and ages of women at their last birth, and on achieved pregnancy among women artificially inseminated. The end of menopause tends to occur during the mid-50s, but natural population data indicate that fecundity usually ends at around 39-41 years. The gap between fecundity and menopause is determined to be about 8-10 years. Findings from the artificial insemination literature indicate that conception rates decline for women older than 30 years. Van Noord-Zaadastra finds that conceptions among women aged 31 years and older are 66% of those for women aged 21-30 years, after 12 cycles of insemination. Young women conceive in about 90% of cases in 24 cycles. Comparisons with natural fertility indicate that use of fresh sperm increases pregnancy rates in cases of insemination. Sex behavior surveys find that coital frequency declines with age, which reduces the risk of pregnancy. Coital frequency is also related to marriage duration; studies reveal that women married for 30 or more years have half the coital frequency rate of women married for four years or less. Reports of intercourse within the past month show a decline by age. Coital frequency and acceptance of extramarital relations have been found to be culture-dependent. Kerin at al. show that oocyte production and fertilization rates decline with age. The quality of the uterus also declines with age. Navot et al. find a high pregnancy rate in women aged 40 years and older when oocytes are donated.


Assuntos
Menopausa , Adulto , Fatores Etários , Comparação Transcultural , Feminino , Humanos , Inseminação Artificial Heteróloga/estatística & dados numéricos , Pessoa de Meia-Idade , Gravidez , Comportamento Sexual
13.
Hum Reprod ; 6(4): 515-8, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1918300

RESUMO

The prediction of ovulation is necessary for oocyte aspiration in a spontaneous cycle and can be reliably achieved only by measuring luteinizing hormone (LH). Since radioimmunoassays of LH take too long for repeated measurements on the same day, we evaluated the possibility of adapting a rapid and fully automated assay of serum LH for use with urine samples. The study group comprised spontaneously ovulating women (38 cycles) who requested artificial insemination. Their serum oestradiol (E2) levels, ultrasound profile (US) and thrice daily urinary LH levels were determined from day 10 of their menstrual cycle. These patients were followed until US signs of follicular rupture were recorded. In all patients, a well-defined LH peak was measured in the urine. This peak lasted 12-15 h and was followed in 35 cycles (no US available for 3) by follicular rupture 9-51 h later. The data were grouped according to the time of the LH peak on day 0. Patients experiencing an LH peak between 0300 h and 0700 h on day 0 had significantly lower levels of E2 on day 0 compared to those with an LH peak between 2200 h and midnight. This is due to the fact that in the patients with an LH peak between 0300 h and 0700 h, E2 levels were already decreasing (from day 1 to day 0), whereas in those with the LH peak between 2200 h and midnight E2 levels were still increasing on the morning of day 0. We conclude that the 30-min IMX LH assay is a reliable, rapid and readily acceptable method for measuring urinary LH and for the prediction of ovulation.


Assuntos
Hormônio Luteinizante/urina , Detecção da Ovulação/métodos , Adulto , Computadores , Estradiol/sangue , Feminino , Fase Folicular/fisiologia , Humanos , Ovulação/fisiologia , Radioimunoensaio , Reprodutibilidade dos Testes
14.
Zygote ; 8(3): 197-202, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11014498

RESUMO

In this study our aim was to characterise the presence and the role of DNA alterations during sperm decondensation in the mouse. To visualise the changes during decondensation we investigated for the presence of DNase I hypersensitive sites in situ and for a putative role for topoisomerase II by examining the effect of teniposide, a topoisomerase II inhibitor, during fertilisation. In situ nick translation without the previous addition of DNase I failed to reveal the presence of endogenous nicks in decondensing sperm and pronuclei whereas preincubation of fixed oocytes with DNase I indicated that decondensing sperm were sensitive to this enzyme. Addition of 100 microM teniposide did not completely inhibit pronuclei formation but its addition to the fertilisation medium did lead to the presence of endogenous DNA nicks in decondensing sperm. These observations suggest that DNase I hypersensitivity during sperm decondensation is related to the dramatic conformational changes that the chromatin undergoes during the decondensation process, in which topoisomerase II may be implicated.


Assuntos
Cromatina/fisiologia , DNA Topoisomerases Tipo II/metabolismo , Desoxirribonuclease I/metabolismo , Fertilização/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Teniposídeo/farmacologia
15.
Biol Reprod ; 49(5): 1083-8, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8286574

RESUMO

A major event in enhancing sperm chromatin stability is the replacement of the histones by protamines during spermiogenesis. In this study, we present results indicating that chromomycin A3 (CMA3) can be used to show protamine deficiency in sperm chromatin. Fixed chromatin of mature mouse spermatozoa showed high fluorescence after treatment with ethidium bromide (EB), but was completely unstained after treatment with CMA3. The same chromatin was found to be highly resistant to in situ nick-translation. In contrast, a substantial fraction of human spermatozoa were positive for CMA3. The accessibility of CMA3 to the DNA of human sperm was eliminated if the slides were previously treated with protamine in situ. This treatment did not affect the accessibility of EB to the chromatin. Individual human sperm samples revealed a substantial frequency of spermatozoa with endogenous nicks, which was found to be the same as the frequency of spermatozoa responding positively to CMA3 staining. Treatment of preparations with protamines prevented the identification of the endogenous nicks. These data as a whole suggest that CMA3 could represent a useful tool for the detection of protamine deficiency in sperm chromatin. Furthermore, confirmation of experiments relating sensitivity to nick translation and positivity to CMA3 may allow an indirect in situ visualization of nicked and partially denatured DNA, which could correlate with certain forms of male factor infertility.


Assuntos
DNA/metabolismo , Protaminas/metabolismo , Espermatozoides/metabolismo , Animais , Cromatina/metabolismo , Cromomicina A3/metabolismo , Dano ao DNA , Etídio , Corantes Fluorescentes , Técnicas Genéticas , Humanos , Técnicas In Vitro , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Espermatogênese
16.
J Assist Reprod Genet ; 13(3): 246-50, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8852887

RESUMO

PURPOSE: We have previously postulated that the chromomycin A3 (CMA3) fluorochrome allows an indirect visualization of sperm chromatin packaging quality and partially denatured sperm DNA. In this study we investigate the relationship between CMA3 positivity and sperm morphology. We also present data on the association between sperm morphology and the presence of endogenous nicks in sperm DNA. METHODS: Semen samples were examined from 81 males of the couples who were consulting for infertility treatment. CMA3 fluorescence was assessed for all samples, while in 24 sperm samples we also examined for the presence of endogenous nicks in the sperm DNA. RESULTS: When sperm morphology was less than 20% normal in a patient, the level of CMA3 fluorescence and presence of endogenous nicks were significantly higher than in patients with a higher incidence of morphologically normal sperm. CONCLUSIONS: CMA3 could be used as an adjunct to the assessment of morphology as an evaluation method for poor sperm. Its value in predicting fertilizing ability when using either SUZI or ICSI awaits to be answered.


Assuntos
Cromomicina A3/metabolismo , Espermatozoides/metabolismo , Biomarcadores , Cromatina/metabolismo , Cromatina/ultraestrutura , Dano ao DNA/genética , Fertilização in vitro , Corantes Fluorescentes/metabolismo , Humanos , Infertilidade , Masculino , Protaminas/metabolismo , Motilidade dos Espermatozoides
17.
Histochem J ; 30(1): 33-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9539205

RESUMO

The nick translation and terminal transferase assays have been compared to test their relative efficiency in detecting DNA breakage in ejaculated human spermatozoa. The results have been correlated with the percentage of chromomycin A3 positive sperm, a fluorochrome that is indicative of the protamination state of sperm. Examination of the ejaculated sperm of 30 subjects revealed that the percentage of positivity to the nick translation and terminal transferase assays did not differ, even when using different fixatives. It is concluded that the inability of the two assays to distinguish the type of DNA damage, as is possible in somatic nuclei, is most probably linked to the unique nature of sperm chromatin. It is proposed that the presence of the damaged DNA may be the remnants of an imperfect spermiogenesis, probably related to an inadequate protamine deposition. This is supported by the strong correlation between the presence of DNA damage and underprotamination as evidenced by chromomycin A3.


Assuntos
Dano ao DNA , Técnicas Genéticas , Infertilidade Masculina/patologia , Espermatozoides/patologia , Cromomicina A3 , Ejaculação , Corantes Fluorescentes , Humanos , Masculino
18.
Mol Hum Reprod ; 4(2): 127-32, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9542969

RESUMO

In this study we investigated the relationship between the presence of bound protamine on mouse and human sperm DNA and the level of chromomycin A3 (CMA3) and 4'6-diamidino-2-phenylindole (DAPI) fluorescence. This was accomplished by performing a competition assay between salmon protamine and fluorochromes on decondensed spermatozoa that had their nuclear proteins extracted and were fixed on slides. Various concentrations (0, 0.005, 0.0225, 0.05, 0.225, 0.5 and 5 mg/ml) of salmon protamine were added to either the CMA3 or DAPI staining solutions. Fluorescence emission measurements of stained sperm nuclei were then performed using a microfluorometer. When the treated decondensed sperm heads were stained with either CMA3 or DAPI all spermatozoa were found to fluoresce intensely. The addition of protamines to the spermatozoa led to an elimination of CMA3 fluorescence, while the intensity of DAPI staining was decreased to approximately 50% at the highest concentrations of protamine. The addition of increasing amounts of salmon protamine also induced the sperm nuclei to regain their initial condensed appearance. This study shows that protamine retains a strong affinity for sperm DNA in situ and that CMA3 fluorescence is a strong indicator of the protamination state of spermatozoa.


Assuntos
DNA/metabolismo , Corantes Fluorescentes/metabolismo , Protaminas/metabolismo , Espermatozoides/metabolismo , Animais , Ligação Competitiva , Cromomicina A3/metabolismo , Humanos , Técnicas In Vitro , Indóis/metabolismo , Masculino , Camundongos , Ovinos
19.
Mol Hum Reprod ; 2(3): 139-44, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9238672

RESUMO

This study aimed to investigate the association between anomalies in sperm chromatin packaging, morphology and fertilization in patients undergoing routine in-vitro fertilization (IVF) or subzonal insemination (SUZI). Sperm chromatin packaging was assessed using chromomycin A3 (CMA3), a fluorochrome specific for guanine-cytosine rich sequences of DNA. One hundred to 150 sperm cells were assessed in 55 patients to compare sperm chromatin packaging and morphology to fertilization after IVF or SUZI. When the morphology and CMA3 fluorescence of individual spermatozoa was assessed, > 75% of the macrocephalic sperm fluoresced in all patients. In contrast, a mean of 37% of the spermatozoa with normal morphology fluoresced in IVF patients compared with 58% of the normal spermatozoa in male factor patients treated by SUZI. SUZI patients displaying a high fluorescence (> 70%) in their spermatozoa also had a significantly lower fertilization rate. Lower packaging quality in morphologically normal spermatozoa may represent a major limiting factor in the fertilizing ability of male factor patients. This study confirms that a high percentage of CMA3 positivity is present in certain forms of male factor infertility and that such a test may be used to distinguish separate populations in morphologically normal spermatozoa.


Assuntos
Cromatina/fisiologia , Espermatozoides/fisiologia , Cromomicina A3/metabolismo , Embrião de Mamíferos/fisiologia , Feminino , Fertilização in vitro/métodos , Fertilização in vitro/estatística & dados numéricos , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/terapia , Inseminação Artificial , Masculino , Microscopia de Fluorescência , Gravidez , Motilidade dos Espermatozoides , Resultado do Tratamento
20.
Biol Reprod ; 52(5): 1149-55, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7626715

RESUMO

Mammalian spermiogenesis involves the replacement of histones by protamines, resulting in a highly compacted chromatin. Upon fertilization, the reverse process occurs. We have previously shown that the chromomycin A3 (CMA3) fluorochrome represents a useful tool for detecting protamine deficiency in spermatozoa. In this study we investigated CMA3 fluorochrome accessibility and the presence of endogenous nicks in maturing and fertilizing mouse sperm. Testicular sperm of stages 1-7 and 8-14 showed high positivity (> 96%) to CMA3, decreasing to 63% in stage 15-16 spermatids. In situ protamination of stage 15-16 spermatids saw an inhibition of CMA3 accessibility. Only 8% of the mature spermatozoa in the efferent ducts were CMA3-positive; this value decreased to 0% in the caput epididymidis. At fertilization, CMA, fluorescence reappears in decondensing sperm. Fluorescein isothiocyanate (FITC) fluorescence, identifying endogenous nicks, was evident in 6% of stage 1-7 spermatids, increased to 22% in stage 8-14 spermatids, and disappeared in stage 15-16 spermatids. During fertilization, endogenous nicks were not observed in decondensing sperm. We propose that 1) the presence of nicks in mouse testicular spermatids suggests that DNA cutting and ligating occurs prior to completion of protamination and 2) the absence of nicks during fertilization indicates that decondensation is not simply the reversal of the initial chromatin packaging process.


Assuntos
Cromatina/ultraestrutura , Fertilização , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Animais , Cromomicina A3/análise , DNA/metabolismo , Feminino , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Histonas/metabolismo , Masculino , Camundongos , Oócitos/ultraestrutura , Protaminas/metabolismo , Interações Espermatozoide-Óvulo
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