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1.
Gynecol Obstet Fertil ; 31(1): 29-42, 2003 Jan.
Artigo em Francês | MEDLINE | ID: mdl-12659782

RESUMO

OBJECTIVE: The present investigation was carried out in order to study the process of metallic corrosion of copper IUD's in utero, to precise its dynamics and location along the IUD and to appraise the influence of eventual calcareous deposition. MATERIAL AND METHODS: A total of 461 copper IUDs representing four standard models were screened by means of optical microscopy. Especially typical samples were studied at higher magnifications under the scanning electron microscope. The obtained data were considered in terms of statistics. RESULTS: It was possible to demonstrate a preferential corrosive activity in the lower part of the IUD without significant variations between the models. It was also possible to precise the steps of the process, to describe its most characteristic aspects and to study the eventual effect of severe calcareous deposition on corroded copper. DISCUSSION AND CONCLUSIONS: Intrauterine copper corrosion is a normal process which occurs preferentially in the cervical portion of an IUD and can lead to the total metal loss. Both its initiation and evolution are submitted to strong individual variations. Thick and compact vaterite deposits may thwart copper erosion in case of drastic and rapid deposition.


Assuntos
Cobre/química , Dispositivos Intrauterinos de Cobre , Microscopia Eletrônica de Varredura , Corrosão , Falha de Equipamento , Feminino , Humanos
2.
Gynecol Obstet Fertil ; 30(1): 22-35, 2002 Jan.
Artigo em Francês | MEDLINE | ID: mdl-11875861

RESUMO

OBJECTIVE: A study was undertaken in order to determine the frequency of the process of calcareous deposition, to clarify the nature of the deposits, their arrangement along the IUD and their possible influence on the appearance of metrorrhagias. MATERIAL AND METHODS: A total of 408 coopper IUD's belonging to four standard models were observed by means of optical microscopy at low magnifications. The most typical samples were studied under the scanning electron microscope and deposits analyzed by crystallography. The data were analysed statistically. RESULTS: It was possible to determine both the frequency and the importance of the process of calcification according to the model of IUD and to the bearing time, to demonstrate a preferential location of concretions and to suspect a sensibility to the phenomenon variable according to the model. It was also possible to clarify the stages of the process of calcification, to describe its most characteristic aspects and to identify the essential component of calcareous deposits. CONCLUSIONS: Calcification concerns roughly over 50% of IUD's in utero. It occurs preferentially on the fundic portion of an IUD. Obviously, the minimal time required for the phenomenon to start as well as to increase its intensity are submitted to strong individual variations. Concretions are composed of vaterite, a distinct variety of carbonate of calcium. They do not seem to be the primary cause of possible metrorrhagias.


Assuntos
Cálcio/análise , Cristalografia , Dispositivos Intrauterinos de Cobre , Microscopia Eletrônica de Varredura , Falha de Equipamento , Feminino , Humanos , Metrorragia/etiologia , Fatores de Tempo
3.
Contracept Fertil Sex ; 26(11): 781-9, 1998 Nov.
Artigo em Francês | MEDLINE | ID: mdl-9864885

RESUMO

Copper release from copper-bearing IUD's was studied in vitro and in vivo using atomic absorption spectrophotometry in deionized water, normal saline solution and normal ovulatory cervical mucus. In these media, copper release from a 375 mm2 DIU occurs without latency, showing comparable amounts for identical time intervals. Daily copper release was shown to be respectively 8 and 11 times higher in cervical mucus and normal saline solution than in deionized water. Although copper ions are detectable in ovulatory cervical mucus under physiological conditions, the copper content appears 5 to 6 times higher in women bearing a copper IUD. Obviously, the copper amount is dependent on the copper exposed surface: the daily in vitro release from a 250 mm2 IUD is 18% inferior to that observed from a 375 mm2 model. In vivo, the daily copper release in ovulatory mucus of 380 or 200 mm2 IUD users is respectively 5 and 3.5 times higher than in controls.


Assuntos
Muco do Colo Uterino/química , Cobre/análise , Dispositivos Intrauterinos de Cobre/efeitos adversos , Espectrofotometria Atômica/métodos , Adulto , Feminino , Humanos , Íons , Teste de Materiais , Pessoa de Meia-Idade , Ovulação , Fatores de Tempo
4.
Hum Reprod Update ; 3(4): 347-58, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9459280

RESUMO

The use of physical techniques such as scanning electron microscopy and microprobe analysis permits the analysis of valuable details of the structure of dried samples of mid-cycle cervical mucus during the period of maximum ferning. From a crystallographic point of view, particular attention was paid to the location, morphology and chemical composition of anisotropic organic sulphate microstructures. As distinct from the isotropic sodium chloride pattern described by Papanicolaou, these appear in a narrow period of time corresponding to the middle of the period of maximum ferning. Anisotropic microstructures were revealed to be tiny isolated crystals or polycrystalline aggregates composed of double salts of potassium and sodium. The potassium/sodium cation ratio, equal to 3/1, was constant in the best specimens. Using a simple polarizing microscope, the detection of anisotropic microstructures may be useful to determine the period of maximum fertility more accurately. In addition, experiments have been carried out in order to determine the relative importance of sulphate anisotropic structures as compared with the whole crystallized surface and to investigate precisely their transience after they appear.


Assuntos
Muco do Colo Uterino/química , Ciclo Menstrual/fisiologia , Sulfatos/análise , Adulto , Anisotropia , Biomarcadores/análise , Biomarcadores/química , Cristalização , Microanálise por Sonda Eletrônica , Feminino , Humanos , Microscopia Eletrônica de Varredura , Cloreto de Potássio/análise , Cloreto de Potássio/química , Cloreto de Sódio/análise , Cloreto de Sódio/química , Sulfatos/química
6.
Andrologia ; 27(6): 345-50, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8597306

RESUMO

The present study compiled the data furnished by 77 different specimens of human bulbo-urethral secretion obtained from 4 donors. It established that Cowper's fluid, allowed to dry at room temperature, gives rise to dendritic crystalline structures showing a remarkable pattern closely resembling fern leaves. In addition to the dendrites, which may develop in some other mucoid secretions and are known to be mainly composed of NaCl crystals, numberless tiny spherulites are also observed within interdendritic intervals, in the central part of the preparations. These spherulites consist of polycrystalline microstructures radiating from a central nucleus. It can be inferred from their structure and localization that they are composed of salts other than NaCl and do not crystallize in the cubic system. Far from being an occasional phenomenon, ferning crystallization is considered to be an unequivocal physical constant of dried human bulbo-urethral fluid. As for interdendritic crystalline spherulites that were described previously as occasional structures present only in ovulatory cervical mucus, both their abundance and range of size variation make them a constant and specific feature of dried Cowper's fluid.


Assuntos
Líquidos Corporais/química , Glândulas Bulbouretrais/metabolismo , Cristalização , Dessecação , Humanos , Masculino , Cloreto de Sódio/química
7.
Contracept Fertil Sex ; 22(11): 720-6, 1994 Nov.
Artigo em Francês | MEDLINE | ID: mdl-7820194

RESUMO

The present article summarizes observations and experimental data obtained from the major vestibular Bartholin's glands in both human and animals with special reference to glandular anatomy as wells as chemical composition, physical properties and physiological roles of the vestibular secretion.


Assuntos
Glândulas Vestibulares Maiores/anatomia & histologia , Glândulas Vestibulares Maiores/fisiologia , Animais , Glândulas Vestibulares Maiores/química , Feminino , Humanos
9.
Hum Reprod ; 6(9): 1192-9, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1752918

RESUMO

Studies using scanning electron microscopic techniques permitted characterization of the nature and structure of the anisotropic elements present in dried preparations of mid-cycle cervical mucus. Sodium and potassium sulphates were located in the dehydrated matrix either isolated or bound to the dendrites. Depending on crystallization conditions, they appeared as well-formed individual crystals or as spherulites.


Assuntos
Muco do Colo Uterino , Colo do Útero/ultraestrutura , Adulto , Anisotropia , Cristalografia , Feminino , Humanos , Masculino , Ciclo Menstrual , Microscopia Eletrônica de Varredura
10.
Contraception ; 43(1): 55-65, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2004529

RESUMO

A study was carried out in order to determine the impact of Nomegestrol acetate on the human cervix and to evaluate the ability of changes induced in cervical mucus to render the cervical canal hostile to spermatozoa at midcycle. Under the influence of Nom Ac, loss of spinability, absence of ferning pattern and drastic tightening of the glycoprotein meshwork rendered midcycle mucus very similar to that elaborated during physiological states under total progesterone dominance. The results obtained in this study gave clear evidence that Nomegestrol acetate may provide cervical blocking thereby preventing sperm transport to the uterine cavity.


PIP: The effect of the oral progestin nomegestrol acetate on spinnbarkeit, ferning and mesh size of midcycle cervical mucus was examined. This 19-norprogestin inhibits ovulation and LH surges, and binds to uterine cytosol progesterone receptors. It is 17-alpha-acetoxy-6-methyl-19-nor-4,6-pregnadiene-3,20-dione, or Lutenyl (Laboratories Theramex, Monaco). Nomegestrol was given to 16 normally cycling volunteers at 2.5 or 5 mg/day for 3 consecutive cycles. Spinnbarkeit was determined automatically with 10 mcl mucus with a spinability-meter (Filancemetre SEFAM), or manually between tweezers if too thick to measure. Cervical mucus was scant, to dry, and related to dose. Spinnbarkeit ranged from absent to 3 mm at 5 mg, and from 11-28 on the meter, compared to 90mm in controls at midcycle. Ferning by standard methods was nonexistent with amorphous structure at 2.5 and 5 mg doses, compared to the usual dendrites and arborization at midcycle in controls. When the mucus was observed by scanning electron microscopy, it resembled that seen at the end of pregnancy or menopause. Mesh size averaged 0.5 mcm at both doses, smaller than the diameter of sperm heads. Nomegestrol acetate is currently used to treat luteal deficiency.


Assuntos
Muco do Colo Uterino/citologia , Glicoproteínas/ultraestrutura , Megestrol , Ciclo Menstrual , Norpregnadienos/farmacologia , Adulto , Muco do Colo Uterino/efeitos dos fármacos , Muco do Colo Uterino/fisiologia , Cristalização , Feminino , Glicoproteínas/metabolismo , Humanos , Masculino , Microscopia Eletrônica , Congêneres da Progesterona/farmacologia , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
11.
Hum Reprod ; 4(4): 359-68, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2745667

RESUMO

A new approach to fern-like structures in dried ovulatory cervical mucus has been carried out. Polarizing microscopy and conventional X-ray devices permitted these well-known structures to be demonstrated as being, both in nature and structure, more complex than previously described. The core of the dendrites appears to be mainly composed of NaCl, but also of KCl. They appear, under the polarizing microscope, as isotropic crystals. Anisotropic structures can be observed either at the periphery of the dendrites or isolated as small spheroliths. Anisotropic structures are insensitive to temperature variations but highly hygroscopic. They become rapidly amorphous when placed at room temperature without caution. The anisotropic period, 7 days long, is inscribed within the ferning period. Maximum anisotropy corresponds to the maximum production of cervical mucus, spinability value and basal body temperature rise. Anisotropic structures may be considered to be characteristic structures occurring spontaneously in ovulatory cervical mucus. These newly described structures consist of sodium or potassium sulphates.


Assuntos
Muco do Colo Uterino , Ovulação , Adulto , Muco do Colo Uterino/análise , Cristalização , Feminino , Humanos , Ciclo Menstrual , Microscopia de Polarização , Potássio/análise , Cloreto de Sódio/análise , Sulfatos/análise , Difração de Raios X
13.
Hum Reprod ; 3(5): 577-82, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3170698

RESUMO

Using laser light scattering, photon correlation and spectral analysis, it was shown that cervical mucus is a non-Newtonian Hydrogel with large meshes (approximately 5 microns). The experimental results are in agreement with a model of hydrogel with weak linkages and are definitely not compatible with a model of entangled macromolecules. Large oscillations, induced by both thermal and mechanical excitation, have been observed in this medium, probably due to its non-Newtonian character.


Assuntos
Muco do Colo Uterino/análise , Feminino , Géis , Humanos , Lasers , Luz , Substâncias Macromoleculares , Modelos Moleculares , Radiação , Espalhamento de Radiação
14.
Eur J Clin Pharmacol ; 35(4): 345-52, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3264244

RESUMO

Alpha-amylase can modify ovulatory cervical mucus in vitro, changing both its structure and an essential rheological parameter, spinability. After 5 min at alpha-amylase concentrations above 4.6 mg/ml, spinability was greatly reduced or even non-existent because of the total liquefaction of the mucus. These concentration levels also induced breakdown of the solid phase of the hydrogel, producing more or less marked abnormalities in mucus crystallization after air drying. In the presence of the highest alpha-amylase concentrations (greater than or equal to 37.5 mg/ml) dendrites could not be formed and only sodium chloride crystals were visible at high magnification under a scanning electron microscope. In the 75 to 1.2 mg/ml concentration range, where alpha-amylase has a significant action on cervical mucus, there was an overall decrease in average spinability as the enzyme concentration fell. The action of the enzyme was greater after 10 min than after 5 min reaction time. For the 10-min reaction time interval, the activity could be adjusted using a squared polynominal regression, whereas for the 5-min reaction time interval a linear regression was a suitable model of enzymatic activity. In the 4.6 to 1.2-mg/ml concentration range, adjustment on a linear model showed that there was a significant effect of alpha-amylase concentration and reaction time on mucus spinability. Statistical analysis of the dose-effect data was compatible with the structural changes in dried cervical mucus demonstrated by scanning electron microscopy.


Assuntos
Muco do Colo Uterino/fisiologia , alfa-Amilases/metabolismo , Adulto , Cristalização , Feminino , Humanos , Microscopia Eletrônica de Varredura , Ovulação , alfa-Amilases/farmacologia
15.
Contracept Fertil Sex (Paris) ; 12(11): 1211-20, 1984 Nov.
Artigo em Francês | MEDLINE | ID: mdl-12266610

RESUMO

Examination under the scanning electron microscope of the arborizations which had developed in dehydrated ovulatory cervical mucus following contact with a contraceptive agent "Alpagelle," with recognized activity only as a spermicide, revealed abnormal structural and exogenous crystallization. 2 conclusions can be drawn which cast new light on the mechanism of action of this contraceptive: the water-soluble active principle of the spermicide enters the aqueous phase of the mucus and eventually saturates this phase; and the water/salt balance is disturbed by the addition of solutes from the spermicide. It can therefore be concluded that "Alpagelle" makes part of the cervical passage lethal to spermatozoa and its protective action is not limited to that of a film coating the vaginal neck and body. It can also be concluded that, by disturbing the salt balance within the aqueous phase, it also alters the cervical "climate" and renders it less suitable for the male gametes.


Assuntos
Biologia , Muco do Colo Uterino , Colo do Útero , Anticoncepção , Anticoncepcionais Femininos , Estudos de Avaliação como Assunto , Serviços de Planejamento Familiar , Genitália Feminina , Genitália , Fisiologia , Pesquisa , Sistema Urogenital , Útero , Anticoncepcionais , Países Desenvolvidos , Economia , Europa (Continente) , França , Tecnologia
17.
Contraception ; 22(5): 445-56, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6894112

RESUMO

An investigation correlating scanning electron microscopic observations with sperm penetration tests carried out on cervical mucus under the influence of low-dose continuous progestogen (Norgestrienone) is presented. The results demonstrate that such type of contraceptive is involved in drastic alterations of mid-cycle cervical mucus at the macromolecular level. The meshwork which constitutes the infrastructure of the cervical secretion appears to be greatly tightened as a result of the treatment, thus giving the woof a general appearance typical of cervical mucus in the late luteal phase. The immobilizing effect of such modified mucus on spermatozoa is demonstrated and the duration of effectiveness after the administration of a last pill on the morning of day 13 is determined.


PIP: The antifertility and obstructive effects toward spermatozoa of a continuous low-dose progestogen contraceptive are examined in this study. Scanning electron microscopy (SEM) observations were correlated with sperm penetration tests carried out on cervical mucus. 11 healthy women aged 19 to 36 who were using no oral contraceptives were studied for 2 consecutive cycles. During the 2nd cycle, the women took a single, daily low-dose progestogen pill (350 ug of Norgestrienone) from the 1st till the 13th day. Blood samples were collected for determination of plasma estrogen levels, which were found to be normal during the control cycle. The progestogen was found to dramatically alter midcycle cervical mucus at the macromolecular level. The meshwork constituting the infrastructure of cervical secretion appeared to be greatly tightened by the treatment, giving the woof a general appearance typical of cervical mucus in the late luteal phase. The mucus framework revealed a tangle of micelles, and sperms leaving the seminal pool in the vagina were faced with such a succession of exhausting physical obstacles that they were unable to penetrate the uterine cavity. The SEM data shows that rendering the midcycle cervical mucus hostile interferes with sperm transport and this probably accounts for the effectiveness of the continuous low-dose progestogen therapy.


Assuntos
Muco do Colo Uterino/efeitos dos fármacos , Norgestrienona/farmacologia , Norpregnatrienos/farmacologia , Transporte Espermático/efeitos dos fármacos , Administração Oral , Adulto , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura
18.
Acta Obstet Gynecol Scand ; 59(1): 55-68, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6770577

RESUMO

The scanning electron microscope was used to study the evolution of the infrastructure of cervical mucus in normal cyclic baboons and in castrated animals treated with ovarian hormones for establishing an artificial cycle. In both groups, the results make conspicuous the progressive enlargement of the filamentous woof, which attains a maximum at midcycle and then decreases by degrees in the second part of the cycle. It was shown that the evolution of the framework is very similar during normal and artificial cycle, with only variations of slight amplitude. Moreover, the variations in the baboon mucus infrastructure closely resemble those described in the human. The results are briefly discussed in the light of known data.


Assuntos
Muco do Colo Uterino/citologia , Estro , Etinilestradiol/farmacologia , Progesterona/farmacologia , Animais , Evolução Biológica , Castração , Muco do Colo Uterino/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Haplorrinos , Microscopia Eletrônica de Varredura , Papio , Gravidez
19.
Eur J Obstet Gynecol Reprod Biol ; 9(5): 289-97, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-264095

RESUMO

The evolution of the mean spinability value of human cervical mucus was studied by means of an automatic device throughout the menstrual cycle and pregnancy and during and after the onset of menopause. The automatic measurement brings to light the major drawbacks presented by manual methods: values previously obtained should be considered as underestimated. The mean spinability value recorded from cyclic mucus exhibits a very significant increase at mid-cycle. Graphical analysis demonstrates that only small differences in the mean spinability value occur as pregnancy proceeds. A progressive and regular decrease in the mean spinability value can be recorded from the very beginning of the menopause. However, the spinability values observed in premenopausal mucus are noticeably higher than those recorded after the onset of the menopause. The numeric data furnished by the automatic measurement are discussed in terms of statistics.


Assuntos
Muco do Colo Uterino/análise , Menopausa/fisiologia , Ciclo Menstrual , Gravidez/fisiologia , Feminino , Humanos
20.
Acta Anat (Basel) ; 104(3): 323-31, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-484194

RESUMO

By means of scanning electron-microscopic investigations, thorn-like projections (TLP) were observed in the cilio-secretory epithelium of the ventral surface of the human endocervix. These projections, which seem to be characteristic of a new cell type, were seen at different stages of the menstrual cycle (days 8, 14 and 21) in 4 apparently healthy fertile women. Striking differences in length, with a maximum size at midcycle, suggest an evolutive process throughout the menstrual cycle. The origin and possible physiological role of TLP in the reproductive process are discussed.


Assuntos
Colo do Útero/ultraestrutura , Adulto , Cílios/ultraestrutura , Epitélio/ultraestrutura , Feminino , Humanos , Menstruação , Microscopia Eletrônica de Varredura , Mucosa/ultraestrutura
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