Biomedical subjects

G Rocchetta

Publications and source records attributed to G Rocchetta.

11 recordsLinked to original sources

PubMed2001

Human oocyte cryopreservation: new perspectives regarding oocyte survival.

The success of human oocyte cryopreservation depends on morphological and biophysical factors that could influence oocyte survival after thawing. Various attempts to cryopreserve human oocytes have been performed with contrasting results. Therefore the effect of some factors, such as the presence or absence of the cumulus oophorus, the sucrose concentration in the freezing solution and the exposure time to cryoprotectants, on human oocyte survival after thawing were investigated. The oocytes were cryopreserved in 1,2-propanediol added with sucrose, using a slow-freezing-rapid-thawing programme. After thawing, the oocytes were inseminated by intracytoplasmic sperm injection (ICSI) and the outcomes of insemination and subsequent embryo development were also recorded. The post-thaw cryosurvival rate was not different for the oocytes cryopreserved with their cumuli partially removed mechanically (56%) when compared with those cryopreserved with their cumuli totally removed enzymatically (53%). On the contrary, a significantly higher survival rate was obtained when the oocytes were cryopreserved in the presence of a doubled sucrose concentration (0.2 mol/l) in the freezing solution and the survival rate was even higher when the sucrose concentration was tripled (0.3 mol/l) (60 versus 82% P < 0.001). Furthermore, a longer exposure time (from 10.5 to 15 min) to cryoprotectants, before lowering the temperature, significantly increased the oocyte survival rate (P < 0.005). Intracytoplasmic sperm injection produced a good fertilization rate (57%) of thawed oocytes and a high embryo cleavage rate (91%) and a satisfactory embryo morphology was observed (14 and 34% for grade I and grade II embryos respectively).

Adult↗

PubMed2000

Technical aspects of oocyte cryopreservation.

Since the successful development in the mouse, the oocyte cryopreservation has been applied with varying success to a number of different species including the human. The recently reported successes in terms of pregnancies obtained by human oocyte cryopreservation are encouraging. Several studies typically reported different rates of survival (20-80%), fertilization (30-60%) and cleavage (32-100%). This variability of results throws some doubts on the usefulness of oocyte cryopreservation in IVF treatment cycles. It remains to be determined whether the relatively different success rates reported in literature, mainly in terms of survival rate, are due to methodological differences. We tried to investigate the effect of some factors on the oocyte survival rate after thawing: the presence or absence of cumulus oophorus and the exposure time of the oocytes to cryoprotectant. We suggest that a combination of several factors including both morphological and biophisical ones can affect the oocyte survival rate.

Animals↗

PubMed2000

Analysis of inheritance of growth trajectories in laboratory populations of guppy-fish.

We analysed the variation of growth trajectories for body length from 40 to 90 days of age in three laboratory populations of Poecilia reticulata. The populations used were two lines of guppy-fish obtained by artificial selection for increased and decreased body length at 70 days and one line maintained under free-breeding condition. The factor analysis performed on the phenotypic correlation matrices among age-specific values of body length showed that a very large portion of the phenotypic variation is confined to a single factor. This factor corresponds to a simultaneous increase/decrease at all ages, hence representing the variation in the height of the growth trajectories. A smaller portion of the variation describes an increase/decrease at early ages followed by the reverse in the later ages, which corresponds to the variation in the shape of the trajectories. The genetic analysis performed on the height and shape of the growth curves showed a additive genetic component for the height in the free-breeding population and for the shape in the selected lines.

Animals↗

PubMed1993

Parental age effects on body size and growth rate in guppy-fish.

We analysed the effect of parental ageing on variations in body size and growth rate of guppy-fish progeny. The resulting data showed that the mean body length of the progeny increases with advancing parental age and this increase might be due to a faster growth rate of progeny from older parents. Given the high correlation linking parental age and maternal size, the involvement of size cannot be ruled out, even though parental age had a greater effect than maternal size on the body length of progeny in one of the two populations considered. Variation in progeny growth rate in relation to variation in parental age might be due to an adaptive mechanism which allows the offspring of older parents to reach reproductive age faster.

Adaptation, Physiological↗

PubMed1992

Ag-NOR protein distribution correlates with patient survival in stage I endometrial adenocarcinoma.

The relationship between argyrophil nucleolar organizer region (Ag-NOR) protein quantity and prognosis was studied in 33 cases of stage I endometrial adenocarcinoma. Ag-NOR protein quantity was measured by image analysis in silver-stained sections from paraffin-embedded samples of curettings. Patients had a minimum 10-year follow-up. Only 2 out of 25 patients exhibiting a mean Ag-NOR protein area of less than 3 microns2 died of cancer, whereas 5 of the 8 patients with a mean Ag-NOR protein area of more than 3 microns2 died of the disease. The present results demonstrate that the Ag-NOR protein value is closely related to patient survival in stage I endometrial carcinoma and that it is a reliable prognostic indicator in this type of carcinoma.

Adenocarcinoma↗

PubMed1980

[Urinary hydroxyproline in advanced breast carcinoma and response to treatment with medroxyprogesterone acetate (MAP) in high doses].

The Authors have studied total urinary hydroxyproline (TUH), together with other hematochemical analyses, in 104 patients suffering from advanced breast cancer with or without bone metastases. TUH escretion is higher in patients with osseous lesions and, if simultaneous pathologic values of TUH and serum alcaline phosphatase occur, the presence of bone metastases is statistically even more probable. Moreover TUH seems to vary in accordance with the clinical response of the disease at osseous level in 46 patients treated with Medroxyprogesterone acetate (MPA) at high doses, showing itself as a possible marker of not negligible clinical value.

Adult↗

PubMed1979