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Biomedical subjects

M Marchini

Publications and source records attributed to M Marchini.

At least 37 records · Page 2Linked to original sources
PubMed1993

Fertility after conservative surgery for adenomyomas.

Reproductive performance was evaluated after conservative surgery for uterine adenomyoma in a prospective, observational study. Twenty-eight women with histologically proven adenomyomas had conservative surgery in the period 1985-1990. Eighteen patients wanting children were regularly followed for a mean +/- SD period of 53.2 +/- 23.5 months. Crude and cumulative pregnancy rates were calculated after the operation. Thirteen (72.2%) women conceived, for a total of 18 pregnancies: nine (50%) ended in term deliveries, seven (38.8%) in spontaneous abortions, one (5.6%) in ectopic pregnancy and one (5.6%) in a pre-term delivery with neonatal death. The cumulative pregnancy rate at 36 months of follow-up was 74.7%. This analysis of a small series indicates that conservative surgery for adenomyomas is associated with a good reproductive prognosis.

Adenomyoma↗
PubMed1993

Collagen-glutaraldehyde interaction as revealed by the D-banding of negatively stained fibrils and computer-drawn band patterns.

Band patterns exhibited under electron microscope by native collagen fibrils fixed with glutaraldehyde (2.5%-5% GA diluted in 0.1M phosphate buffer, pH 7.4) and negatively stained with phosphotungstic acid (1% PTA diluted in the same buffer) were digitized to form both bandings and microdensitometric traces. Collaterally, computer-drawn band patterns and traces were yielded on the basis of the "quarter stagger" model and primary structure of alpha 1(I) and alpha 2(I) tropocollagen chains and by selecting options related to specific collagen-GA interactions. Comparisons between actual and simulated patterns suggest that lysines and hydroxylysines should react with GA residues in a 1:3 ratio, while GA-reactivity of histidyl and tyrosyl residues seem to be excluded. On the other hand, an improvement of simulations was achieved by also selecting hydroxyprolines (in addition to lysines and hydroxylysines), which seemed to react with GA in a 1:1 ratio. Considering the bifunctionality of GA, it is suggested that during fixation, heteropolymers form, composed of GA-hexamers bonded to couples of lysyl and/or hydroxylysyl residues. The hypothesis is advanced of an additional formation of GA-dimers, each bonded to two hydroxyprolines.

Animals↗
PubMed1993

Glutaraldehyde-induced D-band pattern of type II collagen fibrils as revealed by negative staining.

A study was carried out on the negative staining band patterns (1% phosphotungstic acid (PTA) in phosphate buffer, 0.1 M, pH 7.4) exhibited by type II collagen fibrils after treatment with glutaraldehyde (5% in phosphate buffer 0.1 M, pH 7.4) and a comparison was made with the negative staining patterns of glutaraldehyde-fixed type I collagen fibrils. A characteristic D-band pattern was observed for type II collagen fibrils. The gap/overlap ratio was unusually low, with a 0.40 long gap zone and a 0.60 D overlap zone. This banding displayed eleven major light bands instead of the fifteen bands per period observed in the type I collagen patterns. On comparing the two types of microdensitograms, seven negative peaks (light bands) coincided and among them were the peaks corresponding to the N-terminal and C-terminal telopeptide regions. Although less numerous, the negative peaks of type II fibril traces were broader and more marked than those of type I microdensitograms and this feature accounts for the greater stain exclusion capacity of the type II fibrils. This is consistent with the larger quantity of hydroxylysines in type II collagen and, perhaps, with the more abundant hydroxyprolines.

Animals↗
PubMed1993

Correlation between amino acid composition and ultrastructural features of type I and type II native collagen fibrils.

The D-band patterns of native collagen fibrils negatively stained with phosphotungstic acid (PTA) of type II (bovine cartilaginous nasal septum) and type I (bovine reticular dermis) were compared in order to find differences and correlate these with the different amino acid composition of these two collagen types. By analyzing the averaged microdensitograms of the two types of D-banding, differences in type II fibrils were observed: a) the overlap zone was more electron-transparent on average; b) there was a different hierarchy of positive peaks (intraperiod dark bands) b1, b2 and c1; c) a more marked negative peak (intraperiod light band X3) corresponded to the C-terminal extrahelical region; d) there was a different D-location of one negative peak (intraperiod light band Y3). At the same time, different values were calculated for type I and type II tropocollagen molecule total amino acid "bulkiness" (molecular volume/length ratio) and "hydrophobicity", on the basis of literature-reported data. Consistency was found between these values and the differences of the two types of D-banding. The assumption of a correlation between the above two amino acid parameters and negative staining band patterns was supported.

Amino Acids↗
PubMed1993

"GA-banding": a new terminology and a study of the glutaraldehyde-induced band pattern of type I collagen fibrils.

The negative staining D-band patterns of glutaraldehyde-reacted collagen fibrils were compared to those of fresh collagen fibrils. Negative staining was obtained by using 1% phosphotungstic acid (PTA) diluted in phosphate buffer 0.1 M, pH 7.4. The stain was dripped onto grids where native type I collagen fibrils, isolated from bovine dermis, were collected. Ultrastructural pictures were digitized to form microdensitometric traces. The glutaraldehyde-induced patterns showed fifteen light bands (micrographs) or negative peaks (microdensitograms), whose D-locations were constant and characteristic. In order to make this ultrastructural feature a precise reference parameter, these bands were called "GA-bands" and numbered. When comparing this averaged microdensitogram with that of negatively stained fresh fibrils, peak "GA1" and peak "GA7" were observed to correspond to peak "X2" (known as N-terminal telopeptide region) and peak "X3" (known as C-terminal telopeptide region) respectively, while there was no correspondence between the other peaks of the two traces. It means that the regions where preexistent crosslinks exist are unaffected by interaction with glutaraldehyde, while in the other regions, where new glutaraldehyde-crosslinks occur, the band pattern modifies. The unchanged D-location of peaks "GA1" and "GA7" leads to the conclusion that the D-shortening induced by glutaraldehyde is not due to shifting of tropocollagen molecules but to changes in their orientation with respect to fibril long axis or in secondary-tertiary structure of collagen.

Animals↗
PubMed1993

A gonadotropin-releasing hormone agonist versus a low-dose oral contraceptive for pelvic pain associated with endometriosis.

OBJECTIVES: To evaluate the efficacy of goserelin versus a low-dose cyclic oral contraceptive (OC) in improving pelvic pain in women with endometriosis and to compare recurrence of symptoms during follow-up. DESIGN: Open-label, randomized trial. SETTING: University hospital endometriosis center. PATIENTS: Fifty-seven women with moderate or severe pelvic pain and laparoscopically diagnosed endometriosis. INTERVENTIONS: Six-month treatment with goserelin depot (n = 29) or a low-dose cyclic OC (n = 28) followed by 6-month follow-up. MAIN OUTCOME MEASURES: Variation in severity of symptoms during treatment and at the end of follow-up as shown by a linear analog scale and a verbal rating scale. RESULTS: At 6 months of treatment, a significant reduction in deep dyspareunia was observed in both groups, with goserelin superior to the OC at linear analog scale assessment. Nonmenstrual pain was diminished on both scales without differences between treatments. Women taking the OC experienced a significant reduction in dysmenorrhea. At the end of follow-up, symptoms reappeared without differences in severity between the groups. CONCLUSIONS: Low-dose cyclic OCs may be a valuable alternative for the treatment of dysmenorrhea and nonmenstrual pain associated with endometriosis. Symptoms recurred in most subjects 6 months after drug withdrawal.

Adolescent↗
PubMed1992

Endometrial patterns during therapy with danazol or gestrinone for endometriosis: structural and ultrastructural study.

We treated 36 women with laparoscopically proven endometriosis with danazol 600 mg/d (n = 17) or gestrinone 5.0 mg/wk (n = 19) for 6 months. Endometrial samples were obtained before and at 3 and 6 months of treatment and were studied by light, scanning, and transmission electron microscopy. At 3 months of treatment, the endometria of the danazol-treated patients were more atrophic than those of the women who received gestrinone. Some cell organelle involution was evident in patients of both treatment groups. After 6 months of treatment, marked endometrial atrophy was observed in all the patients, including those in whom spotting had occurred. The ultrastructural investigation demonstrated complete involution of the cytoplasmic organelles with cytoplasmic collapse in glandular cells of patients treated with danazol, whereas in the gestrinone group degeneration phenomena were observed in both nucleus and cytoplasm. Irregular secretory transformation was seen in the endometria of patients in both groups. Long-term treatment with danazol caused endometrial atrophy similar to that induced by gestrinone, but it appeared earlier; thus, the former drug seems preferable in short-term treatment.

Adult↗
PubMed1992

Ultrastructural aspects of endometrial surface in Kartagener's syndrome.

The endometrium of an infertile patient with Kartagener's syndrome showed initial secretory phase characteristics at SEM, whereas TEM analysis demonstrated several alterations in the central and peripheral microtubular distribution in 87% of the cilia examined. Such aspects seemed appropriate for a normal implantation, but the ciliary immotility or dyskinesia could cause an altered flow of the endometrial secretions and compromise the upstream movement of the spermatozoa.

Adult↗
PubMed1992

Superovulation with human menopausal gonadotropins in the treatment of infertility associated with minimal or mild endometriosis: a controlled randomized study.

OBJECTIVE: To determine the efficacy of superovulation with buserelin acetate, human menopausal gonadotropins (hMG), and human chorionic gonadotropin (hCG) in the treatment of infertility associated with minimal or mild endometriosis. DESIGN: Prospective, randomized, controlled study. SUBJECTS: Forty-nine infertile women with a laparoscopic diagnosis of endometriosis stage I (n = 29) or II (n = 20) according to the revised American Fertility Society classification, randomly assigned to three superovulation cycles (n = 24) or 6 months' expectant management (n = 25). MAIN OUTCOME MEASURES: Cycle fecundity rates and cumulative pregnancy rates (CPR) in the two groups. RESULTS: Nine pregnancies were obtained in the superovulation-treated patients and six in the nontreated ones. The cycle fecundity rates and CPR were 0.15% and 37.4% after three superovulation cycles and 0.045% and 24% after 6 months of expectant management (P less than 0.05 and P = not significant, respectively). The women who did not achieve a pregnancy after three cycles of superovulation were followed for a total of 50 months during which no therapy was given. One pregnancy started in this period (cycle fecundity rate = 0.020). One spontaneous abortion occurred in each group. Three treated patients had multiple pregnancies, and four had ovarian hyperstimulation syndrome. CONCLUSION: Superovulation seems to be associated with a better cycle fecundity rate but not a better CPR than expectant management in infertile women with endometriosis stages I and II. The efficacy and side effects of this therapeutic approach should be evaluated in larger series.

Adult↗
PubMed1992

HLA-associated susceptibility to HIV-1 infection.

We studied HLA antigen distribution of 50 heterosexual partners of HIV+ drug abusers with more than 1 year of sexual exposure to HIV, 36 children born to seropositive mothers and 61 haemophiliac patients exposed to presumably infectious clotting factor concentrates. B52 and B44 antigens were associated with HIV resistance while B51 was associated with HIV susceptibility. Forty-nine HIV+ drug abusers, spouses of heterosexual partners studied and 25 HIV+ mothers of the children were also typed. DR11 phenotype was associated with infectiousness of HIV+ subjects. Our data suggest that the HLA region controls susceptibility to infection with HIV and infectiousness of HIV+ subjects in different risk groups.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tendons, while in the optic nerve sheath the fibrils appear smaller and uniform, similar to those commonly observed in reticular tissues, vessel walls and skin. Freeze-fracture also reveals these fibrils to have different subfibrillar architectures, straight or helical, which correspond to 2 distinct forms of collagen fibril previously described (Raspanti et al. 1989). The other extracellular matrix components also vary with the particular collagen fibril structure. Despite their common embryological derivation, the dura mater, optic nerve sheath and sclera exhibit diversification of their extracellular matrix consistent with the mechanical loads to which these tissues are subjected. Our observations indicate that the outermost sheath of the optic nerve resembles the epineurium of peripheral nerves rather than the dura to which it is commonly likened.

Animals↗
PubMed1992

[Cytochemical study of human sperm metabolism during in vitro capacitation after cryopreservation].

To study the effects of deep freezing on the energy metabolism of human spermatozoa, we investigated, by cytochemical quantitative methods, cytochrome oxidase and lactate dehydrogenase activities of fresh and frozen human spermatozoa during in vitro capacitation. Fresh and frozen human spermatozoa were incubated in Biggers, Whitten and Wittingham's medium supplemented with 15% heat-inactivated human serum. Both histoenzymological reactions can be quantitated and have been evaluated by microdensitometric method. The results indicate that human spermatozoa depend almost entirely on anaerobic glycolysis during in vitro capacitation and suggest that both aerobic and anaerobic metabolism in spermatozoa are only slightly impaired by freezing-thawing and storage.

Adult↗
PubMed1991

Endometrial patterns during danazol and cyproterone acetate treatment for endometriosis: structural and ultrastructural study.

We studied the endometrial structure and ultrastructure in serial biopsies from 16 patients with endometriosis treated with danazol (n = 9) or the combination cyproterone acetate plus ethinyl estradiol (n = 7) for 6 months. Biopsies were performed before and at 3 and 6 months of treatment. The material obtained was studied by light (LM), scanning (SEM) and transmission electron microscopy (TEM). A morphometric analysis was performed evaluating three morphometric and three stereologic indices. The results indicate that danazol had a progestational effect on endometrial glands and stroma, associated with a marked hypotrophy of the mucosa. The cyproterone acetate/ethinyl estradiol combination induced progressive atrophy of the endometrium with an increase in the stromal component and a reduction of glandular tissue.

Adult↗
PubMed1991

Intranasal buserelin versus surgery in the treatment of uterine leiomyomata: long-term follow-up.

Forty-two women with symptomatic uterine myomas, candidates for myomectomy or hysterectomy, were randomized to 6 months' treatment with buserelin 1200 micrograms/day intranasally (n = 22) or immediate surgery (n = 20). After buserelin treatment or operation the patients were followed for at least 12 months. Buserelin was well tolerated, the uterine volume fell from 465 +/- 168 to 273 +/- 88 cm3, and hemoglobin values normalized in all anemic patients. Rapid myoma regrowth was observed in all patients in the buserelin group after treatment withdrawal. Pregnancy occurred during follow-up in one of five buserelin-treated myomectomy candidates. Menorrhagia recurred in eight of 15 buserelin-treated hysterectomy candidates, and a hysterectomy was required but no transfusion was needed. Two women entered natural menopause and were considered cured. In the surgery group all operations were uneventful: three women conceived after myomectomy, whereas four of the patients that underwent hysterectomy required transfusions. Thus buserelin treatment appears to be indicated for infertile patients when surgery is contra-indicated or could cause adhesions, and for hysterectomy candidates in perimenopausal age and/or with secondary anemia.

Administration, Intranasal↗
PubMed1991

Follicular fluid enhances sperm motility and velocity in vitro.

Forty-three follicular fluids (FFs) obtained during laparoscopy were tested in vitro for their effect(s) on sperm motility using gametes obtained by the swim-up procedure. Both the proportion of motile sperm and the velocity distribution patterns were evaluated as function of time by multiple-exposure photography technique. At the various incubation periods considered, all FFs maintained or then enhanced sperm motility as compared with the paired control suspension incubated with a sperm survival medium. The results of the sperm contact test for FFs from women who achieved pregnancy versus FFs from women who remained infertile were not significantly different for both parameters measured. Comparing these with our previously reported results, we may hypothesize that FF released at ovulation into the peritoneal cavity may counteract some sperm-immobilizing effect of peritoneal fluid, thereby increasing the fertility potential of the male gametes.

Ascitic Fluid↗
PubMed1991

Secretory changes in preovulatory endometrium during controlled ovarian hyperstimulation with buserelin acetate and human gonadotropins.

Twenty-one patients with unexplained infertility underwent controlled ovarian hyperstimulation with buserelin acetate and human menopausal and chorionic gonadotropins, and follicular growth was monitored by ultrasonography and daily 17 beta-estradiol (E2) assays. Endometrial biopsy was performed when E2 levels were greater than or equal to 250 pg/mL per follicle and the follicular diameter was greater than or equal to 17 mm. As controls, we studied 20 preovulatory endometrial biopsies from patients with a male infertility factor. The biopsy material was examined at light, scanning, and transmission electron microscopes, and a morphometric analysis was performed. Preovulatory endometrial mucosa during controlled ovarian hyperstimulation showed accentuated proliferative aspects in both the glandular and stromal components and more frequent early secretory phenomena compared with the controls. The preovulatory progesterone (P) levels observed in our study seem to exclude the possibility that such early secretory aspects of the hyperstimulated endometrium are because of higher P concentrations in patients compared with controls.

Buserelin↗
PubMed1991

Negative staining and genesis of D-periodicity in native collagen fibrils.

An investigation was carried out on the mechanism which gives rise to the banding exhibited by collagen fibrils after negative staining. The negative staining (phosphotungstic acid) band patterns of native collagen fibrils (type I), isolated from calf reticular dermis, were compared with computer-drawn band patterns. The stimulations were based on the primary structure of bovine type I collagen, the "quarter stagger" molecular packing and different conformations of telopeptides. The results suggest that in negative staining, the stain exclusion effect depends on both spatial factors and water repelling factors being the "bulkiness" (molecular volume/length ratio) as well as the hydrophobicity of the amino acids of alpha 1 (I) and alpha 2 (I) chains directly involved. No final conclusion could be drawn about the contribution of positive staining to negative staining. Improvements in the simulations were achieved when the telopeptides were shaped according to particular conformational models.

Animals↗