Biomedical subjects

C Crisosto

Publications and source records attributed to C Crisosto.

At least 19 recordsLinked to original sources

PubMed1992

Genotypic variability in vulnerability of leaf xylem to cavitation in water-stressed and well-irrigated sugarcane.

Genotypic variability in vulnerability of leaf xylem to water-stress-induced cavitation was determined in four sugarcane (Saccharum sp.) clones using detached leaf segments in a hydraulic conductivity apparatus. Vulnerability curves were constructed by plotting the percentage of maximum conductivity versus leaf water potential (psi(I)) and fitting curves using a Weibull function. The psi(I) at which each clone lost 10, 50, and 80% of maximum conductivity was determined. Maximum conductivity per unit of leaf width was positively associated with metaxylem vessel diameter. The commercial clone H65-7052 exhibited the highest and the nondomesticated S. spontaneum exhibited the lowest conductivity. All four clones lost substantial conductivity at values of psi(I) less negative than -1.4 MPa, but H65-7052 was able to maintain 50% conductivity to lower psi(I) than the other clones. S. spontaneum sustained the most negative psi(I) (-1.99 MPa) before reaching the 80% conductivity loss point. Clone H69-8235 was consistently the most vulnerable to initial loss of conductivity. These vulnerability functions were used in conjunction with field measurements of psi(I) to estimate diurnal losses in leaf hydraulic conductivity under irrigated and droughted conditions. H69-8235 lost up to 50% of its conductivity during the day, even when well irrigated, and more than 80% when subjected to drought. The other clones exhibited lower conductivity losses. These losses are apparently reversed overnight by root pressure. Despite their close genetic relationships, these clones exhibited large differences in conductivity, in the vulnerability of their xylem to cavitation, and in gas exchange behavior. The potential for altering water relations by selecting for particular hydraulic characteristics is discussed.

Journal Article↗

PubMed1992

[The results of a program of in vitro fertilization and tubal embryo transfer (ZIFT)].

Twenty-one sterile couples, between September 1989, and August 1991, were treated for ovulation stimulation of their cycles, in order to practice in them, a in vitro fertilization and tube embryo transfer (ZIFT). Two protocols of ovulation induction were used, both with leuprolide acetate (Lupron), one in the luteal phase and the other in follicular phase and since the second or the fourth day of the cycle, respectively, gonadotropins were added (Metrodine and Pergonal). Out of all the twenty-nine initiated cycles, twenty-seven were aspirated (93.1%) and twenty-four reached an embryo transfer (82.8%). Seven clinic pregnancies were obtained (29.17% per transfer) and four deliveries (16.67% per transfer). The sterility period average was 69.64 +/- 36.6 months and the patients age average was 34.1 +/- 4.38 years. The global rate of fertilization was 63.53%. With luteal phase Lupron best results were got (pregnancy rate of 38.46% per transfer) and there were not considerable difference in the number of gonadotropins ampulla employed. When embryos were transfer to the tubes and the uteri the pregnant rate was 50% per transfer, in comparison to 18.75% when transfer was made only in the tubes.

Chile↗

PubMed1989

[In vitro fertilization program. Preliminary results].

Three infertile couples were submitted to in vitro fertilization and uterine embryo transfer (IVF+ET) and 7 to in vitro fertilization and pronuclear stage tubal transfer (IVF+PROST). In order to programmed menstruation Norethisterone, 10 mg daily, were administered during the cycle preceding the one of controlled ovarian hyperstimulation. In order to inhibit endogenous production of FSH and LH, leuprolide acetate, a Gn-RH agonist, was injected subcutaneously 1 mg daily during 6 days and 0.5 mg fowardly from the luteal phase of the cycle proceeding the one of hyperstimulation until the day of HCG administration. To achieve superovulation pure FSH (Metrodine), HMG (Pergonal) and HCG (Endocorion) were used. Oocyte retrieval was performed through transvaginal puncture under ultrasonographic control. For oocyte and embryo identification and classification, spermatozoa separation and capacitation and gamete insemination and incubation procedures habitual techniques were employed. Pronuclear embryo tubal transfer was performed through a laparoscope 17 hours after insemination and embryo transfer to the uterine cavity after 48 hours. Nine of 10 patients responded to gonadotrophin hyperstimulation and were submitted to ovarian puncture. 69 oocytes (7, per patient) were obtained, 59 (81.15% of which were mature. 74.55% of the inseminated oocytes fertilized. Two patients got pregnant: one, submitted to IVF+PROST, presently has a multiple pregnancy with triplets and the second, submitted to IVF+UT, had a missed abortion at 8 weeks of pregnancy.

Adult↗

PubMed1989

[Clinico-echographic study of the ovulatory phase, spontaneous and induced, conceptional and non conceptional cycles].

We present the results obtained on 110 menstrual cycles of 87 patients; echography study of ovulation, immunologic LH determination, basal body register card and serial cervical mucus score, since -6 to 0 day. Echography study determined follicular diameter, endometrial bulk and the presence of liquid in the cul-de-sac. We considered only those patients in whom the disappearance of the follicle was observed 24 hours before; being this fact, the indicator of ovulation, related to all other variables. These patients presented spontaneous (47.3%), epimestrol (28.2%) or clomiphene induced (24.5%) cycles, and they turned out to be pregnant or not in that cycle, (34.6%, 25.8% and 37.0% respectively). It was 36 (32.7%) pregnant women in all the The three follicular diameter curves for pregnant cycles, were similar being the preovulatory follicular range 21.5 mm for spontaneous cycles, 18.9 mm for epimestrol induced cycles and 20.7 mm for clomiphene induced cycles. Conceptional range was from 15 to 22 mms, 15 to 22 mm, and 14 to 27 mms, respectively. We didn't observe free fluid in cul-de-sac in 5 pregnant cycles (13.9%). Most of positive LH, are about -2 and -1 (21% and 50%, respectively). There were one pregnant patient and 2 no pregnant patient with repetitive, negative LH. In 50% of patients who became pregnant, the Nadir was on -1 day. In spontaneous conceptional group, bad cervical score was not observed. The good cervical score period is longer on conceptional group than in those with epimestrol. On conceptional group, dissociation between best score day and the day of ovulations was not observed, fact that we observed in non-conceptional group.

Clomiphene↗

PubMed1989

[Sheehan syndrome and spontaneous pregnancy: report of 2 cases].

Two patients receiving substitution therapy for Sheehan syndrome became pregnant. No pituitary trophins, except LH responded to stimulation with the hypothalamic hormones TRH and Gn-Rh, or insulin induced hypoglycemia. Computed tomography showed a normal size sella with arachnoid cyst.

Adult↗

PubMed1979