Search PubMed⌕ Search

Biomedical subjects

R Campo

Publications and source records attributed to R Campo.

At least 91 records · Page 5Linked to original sources
PubMed1994

A 14 kDa release factor is involved in GTP-dependent beta-tubulin folding.

The tubulin folding pathway is a model system to understand protein folding in the cell. It involves the interaction of several chaperones, including TCP-1 and other as yet uncharacterized factors. Release of tubulin monomers from folding intermediates (C900 and C300) and their incorporation into tubulin dimers is dependent on GTP hydrolysis, magnesium ions and release factors. In this work, we have purified to homogeneity the protein factor responsible for the release of beta-tubulin monomers from C300 complexes. It has an apparent molecular mass of 14 kDa (p14) as judged by SDS electrophoresis. The protein behaved as a dimer of about 28 kDa when analyzed by gel filtration chromatography. Furthermore, the p14-dependent release of beta-tubulin monomers from C300 complexes takes place in the presence of GTP. These results suggest that p14 is a new chaperone that assists in tubulin folding by facilitating the acquisition of the native conformation.

Adenosine Triphosphate↗
PubMed1994

Heterotopic ovarian pregnancy after clomiphene ovulation induction.

Heterotopic pregnancy is a life threatening condition which seems to occur more frequently than previously estimated. We report a case of combined ovarian and intrauterine pregnancy after clomiphene treatment. Diagnosis was delayed because clinical presentation was atypical and ultrasound was falsely reassuring. The neonate was healthy but presented with a single umbilical artery. When an ectopic gestation is suspected after induction of ovulation or assisted reproductive technologies the presence of an intrauterine pregnancy can no longer be considered reassuring and an heterotopic pregnancy has to be ruled out.

Adult↗
PubMed1994

Methods to increase the success rate of artificial insemination with donor semen.

Donor insemination was performed in two fertility clinics using cryopreserved semen from the same sperm bank. Donors were selected in agreement with American Fertility Society recommendations. In the first clinic, cup insemination was combined with intra-uterine insemination in 321 cycles. Follicular development was closely monitored with vaginal echography and serum hormonal measurements. In the second clinic, 1287 insemination cycles were performed using intra-cervical insemination, timed only on basal body temperature. In the first clinic, a total of 53 pregnancies were obtained, of which seven were in 55 unstimulated cycles (12.5%), 21 in 159 cycles with clomiphene citrate stimulation (13.1%, P > 0.1), and 25 in 107 cycles stimulated with clomiphene plus human menopausal gonadotrophin (HMG) (23.9%, P < 0.03). No multiple pregnancies were observed in the latter group. In the second clinic, 159 pregnancies occurred during 1287 insemination cycles (12.4%). It is concluded that neither intra-uterine insemination, nor hormonal and echographic cycle monitoring, nor clomiphene citrate enhances the success rate of artificial insemination with donor semen, but HMG treatment probably exerts a favourable effect.

Adult↗
PubMed1993

Hysteroscopic findings in patients with a cervical polyp.

OBJECTIVE: Our objective was to determine the presence of intrauterine lesions in patients with a cervical polyp. STUDY DESIGN: We performed a retrospective analysis to determine the influence of hormonal treatment and age on 165 patients with a cervical polyp and bleeding on admission. All 165 patients underwent a diagnostic hysteroscopy to rule out intrauterine lesions, including polyps, fibroids, hyperplasia, and adenocarcinoma. RESULTS: Endometrial polyps were found in up to 26.7% of patients who had a cervical polyp. In patients undergoing a combined pill treatment this incidence was much lower (8.3%). Menopausal patients had a 56.8% incidence of cervix-related endometrial polyps, and hormone replacement therapy did not significantly increase (45.7% vs 28.6%) the incidence of coexisting polyps. All cervical polyps present during tamoxifen treatment were associated with endometrial polyps. Abnormal vaginal bleeding was of no clinical significance in excluding concomitant endometrial polyps. CONCLUSIONS: All menopausal patients with a cervical polyp could benefit from a diagnostic hysteroscopy. Premenopausal patients receiving a combined pill treatment are the least likely to have coexistent endometrial polyps.

Adult↗
PubMed1993

Subzonal insemination: a prospective randomized study in patients with abnormal sperm morphology.

OBJECTIVE: To evaluate in a prospective randomized study the outcome of subzonal insemination (SUZI) in patients with male subfertility. DESIGN: In a period of 7 months, 48 patients underwent IVF treatment for male subfertility reasons. Normal insemination and SUZI were performed on sibling oocytes. Patients were divided into three groups depending on the sperm morphology (strict criteria): group 1, 10% to 14%; group 2, 5% to 10%; group 3, 0% to 5%. SETTING: Private fertility center in Leuven, Belgium. MAIN OUTCOME MEASURES: The fertilization rates, cleavage rates, implantation rates, and pregnancy rates between the normally inseminated and the SUZI-treated group were compared. RESULTS: The fertilization rate with SUZI was significantly higher (32%) than after normal insemination (7%). The difference was striking in groups 2 and 3 (35% and 33% versus 11% and 4%). CONCLUSION: This study indicates that SUZI increases the fertility outcome in patients with male subfertility and that there is a marked difference in fertilization rate when morphology, using strict criteria, is < 10%.

Female↗
PubMed1993

Mitochondrial distribution after fast embryo freezing.

Mitochondrial distribution pattern after ultrarapid freezing in dimethylsulphoxide was assessed in human multipronucleate zygotes, 2-cell and 4-cell stage embryos using rhodamine 123. The mitochondrial distribution pattern was evaluated at 37 degrees C after a 30 min incubation in rhodamine 123 solution, 4 h and 24 h after thawing. Non-frozen human unfertilized oocytes, 2-cell and 4-cell embryos used as a control showed a homogeneous distribution of mitochondria throughout the cytoplasm, while there was sequestration of mitochondria from the cortex to the region surrounding the pronuclei in multipronucleate zygotes. Morphologically intact multipronucleate zygotes, 2-cell and 4-cell stage embryos after quick freeze-thawing showed the same mitochondrial distribution pattern found in the unfrozen controls. Mitochondria exhibited a typical severe aggregation (clumping) throughout the cytoplasm when non-viable single blastomeres or embryos at thawing were exposed to rhodamine 123. Our study indicates that quick freezing does not affect subcellular structures. The well-organized and specific mitochondrial distribution appeared still to be present after frozen storage, and subcellular structures seemed to be rather resistant targets for cryo-injury.

Cleavage Stage, Ovum↗
PubMed1993

Apparent culture-negative endocarditis of the prosthetic valve caused by Cardiobacterium hominis.

To date, there have been fewer than 50 reported cases of endocarditis caused by C hominis. Only six of these involved prosthetic heart valves. To our knowledge, in no previous case has the organism been cultured directly from the valve, an aspect we believe gives our case special relevance. Our case also illustrates the fact that whenever a fastidious organism is thought to be responsible for infective endocarditis, not only blood cultures but also cardiac tissue cultures should be held beyond the customary period of time.

Aged↗
PubMed1991

Fluorescein diacetate assessment of embryo viability after ultrarapid freezing of human multipronucleate embryos.

OBJECTIVE: To assess embryo viability after ultrarapid freezing-thawing. DESIGN: We studied the fluorescence pattern of 35 ultrarapidly frozen-thawed multipronucleate human embryos exposed to fluorescein diacetate. SETTING: All the embryos were obtained from the Medical Center for Fertility Diagnostics and In Vitro Fertilization and Embryo Transfer at Leuven (Belgium), a private care center. PATIENTS, PARTICIPANTS: None. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The fluorescence pattern was evaluated at room temperature after a 1-minute incubation in fluorescein diacetate solution, 4 hours and 24 hours after thawing. RESULTS: Healthy human multipronucleate embryos, when exposed to fluorescein diacetate, accumulated intracellular fluorescein and fluoresced brightly under ultraviolet light. On the other hand, embryos presenting submicroscopic cell membranes damage caused by different processes (e.g., high or low temperatures) lost the ability to accumulate intracellular fluorescein. All the ultrarapidly frozen embryos with normal looking blastomeres fluoresced brightly after a short exposure to fluorescein diacetate. CONCLUSIONS: Our experiments indicate an intact cell membrane permeability and an integrity of the intracytoplasmatic esterase enzyme activity of human embryos ultrarapidly frozen.

Blastocyst↗
PubMed1991

Site and size of bleeding peptic ulcer. Is there any relation to the efficacy of hemostatic sclerotherapy?

In 78 patients with high-risk bleeding peptic ulcers (either with active bleeding or non-bleeding visible vessel) endoscopic hemostasis by injection of adrenaline and polidocanol was attempted. Sclerotherapy was performed in 70 (90%) patients. Initial hemostasis was achieved in 35 (94.5%) patients with active bleeding, and permanent hemostasis in 61 (87%). Efficacy of injection therapy was significantly lower in ulcers larger than 2 cm (p = 0.001), and in those located on the posteroinferior duodenal wall (p = 0.03). It was not possible to perform endoscopic injection in 8 (10%) patients due to difficulty of access, lesions located mainly high on the lesser gastric curvature and on the posteroinferior duodenal wall. From these results we conclude that endoscopic injection is a very useful technique for the initial treatment of high-risk bleeding peptic ulcer, although the size and anatomical location of the lesions may be a limitation of its use.

Aged↗
PubMed1991

[Evaluation of transparietal hepatic cholangiography in the diagnosis of cholestatic syndrome].

Three hundred and thirty-two percutaneous cholangiograms were done in 313 patients. The etiology was benign in 137 cases and malignant in 152 instances. The level of obstruction was correctly localized in 97.8% of cases. The total sensitivity was 88.5% and specificity 95.9%. Positive predictive value 95.4% and negative predictive value 89.6%. Major complications occurred in 3.3% of cases. Complications occurred more frequently when the bile ducts were dilated. They were not related to the number of attempts to puncture ther biliary tree or the experience of the physician.

Aged↗
PubMed1990

[Epidemiological research on dental caries incidence in a sample of the school-age population of Ragusa].

The authors have conducted an epidemiologic research into a sample of 1500 schoolboys of Ragusa aged between a six and a twelve years old, to evaluate the incidence of dental caries. A small percentage of children practice correct oral cleanliness and know the importance of regular medical check-ups. The result is that, since childhood, a large incidence of dental caries is present whether in permanent teeth or in deciduous teeth, often precociously extracted and rarely treated with all the negative consequences that follow. Therefore it's necessary to intensify both information programs and dental prevention at a scholastic level in the intervention of a valid program of social and preventive medicine.

Age Factors↗
PubMed1990

Survival and pregnancy outcome after ultrarapid freezing of human embryos.

Contrary to the belief that rapid cooling and thawing of mammalian embryos is detrimental to survival, it has been shown that under certain conditions mammalian embryos can survive rapid freezing-thawing. In this study, 237 human fertilized oocytes (93 pronucleates, 20 multipronucleates, and 124 cleaved embryos) were frozen for a period of 1 day to 7 months using the ultrarapid freezing system. After thawing, 94% of the embryos in the pronucleate group and 89.5% in the multipronucleate group showed normal morphological features, and 79% and 71%, respectively, started to cleave. Forty cleaved embryos were also frozen-thawed, but only 15 (37.5%) survived at thawing. Thirty-four frozen-thawed cleaved embryos were transferred to 20 patients during spontaneous cycles. Four patients became pregnant.

Cell Division↗