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Biomedical subjects

S Michalas

Publications and source records attributed to S Michalas.

At least 73 records · Page 4Linked to original sources
PubMed2000

Adhesions: laparoscopic surgery versus laparotomy.

This study was undertaken to assess the effectiveness in pregnancy rates of microsurgery and operative laparoscopy in adhesiolysis. Adhesions were found to be the sole infertility factor in 15% of our patients. One hundred and ninety infertile patients with periadnexal adhesions as the only cause of their infertility were treated by microsurgery (86) or operative laparoscopy (104) and were followed up for 24 months. Our results indicate that advanced laparoscopic surgery in general is as effective as microsurgery in healthy infertile patients with adhesions but offers some advantages in comparison to laparotomy. Factors that adversely affect the postoperative success rates are the age of the women, the duration of infertility, and the severity of the adhesions.

Adult↗
PubMed2000

Biological factors in culture media affecting in vitro fertilization, preimplantation embryo development, and implantation.

Optimal culture conditions are of paramount importance for in vitro fertilization of gametes, preimplantation embryo development, and implantation for all species. Water is the basis of all culture media, and ultrapure water should be employed. The main energy sources of a medium are lactate, pyruvate, and glucose. The concentrations of the first two vary in different media, whereas the latter is necessary mainly for the later stages (morula to blastocyst) of development. A fixed nitrogen source is essential for implantation embryo development whether this is provided by amino acids, albumin, or serum. Suboptimal culture conditions can block development. Pronuclear zygotes of most species (but not human) arrest at some point between the two-cell and the 16-cell stage. Modifying culture conditions can lead the embryos to develop through this block. Hypoxanthine also causes a two-cell block to mouse pronuclear zygotes, and this again depends largely on culture conditions. Simple culture media are bicarbonate-buffered systems with pyruvate, lactate, and glucose. Complex media, such as Ham's F-10, contain in addition amino acids and other elements found in serum. Human tubal fluid simulates the fallopian tube microenvironment. EDTA, gonadotropins, growth factors, and other substances can be included in the media to stimulate development. Coculture of embryos with oviductal cells has shown promising results.

Animals↗
PubMed2000

Genetic amniocentesis in women 20-34 years old: associated risks.

The aim of this retrospective controlled study is to evaluate the impact of predisposing factors on amniocentesis-related fetal loss. It comprises 3910 consecutive cases of women, aged 20-34 years, who had genetic amniocentesis during the years 1992-97 (study group). The control group comprised 5324 women under 35, at low risk for Down syndrome, during the same period. The fetal losses in both groups were analysed, in respect of: (a) maternal historical conditions; and/or (b) bleeding during current pregnancy. The leading indication for amniocentesis in women 20-34 years was maternal anxiety, mainly for marginal age (33-34 years), which accounted for a remarkable 34.4% of the study group. Total fetal loss rate up to the 28th week was 2.1% in the study group versus 1. 5% in controls. A history of previous spontaneous or induced abortions, as well as bleeding during the current pregnancy, was associated with a substantial rise of fetal loss in both groups. In cases with no predisposing factors, the added fetal loss rate was 0.03%. Previous abortions and bleeding during the current pregnancy are associated with the most fetal losses after amniocentesis. In the absence of these, the added fetal loss rate (0.03%) is non-significant.

Abortion, Spontaneous↗
PubMed2000

The role of antibiotics after dilatation and curettage in women with metrorrhagia in the prevention of pelvic inflammatory disease.

A follow-up study was carried out in 67 healthy women with negative vaginal-cervical cultures after an endometrial curettage for metrorrhagia. The women were separated into two treatment groups and clinically followed for one month after the operation. The first group included 33 women (aged 23-67, mean 43) who received doxycycline 200 mg daily for a period of one week after the procedure. The second group included 34 women (aged 28-70, mean 43.5) who did not receive any antibiotic regimen after the dilatation and curettage. Four and three women from the 1st and 2nd group, respectively, developed PID during follow-up; a difference not statistically significant.

Adult↗
PubMed2000

Breast tumors during adolescence.

A variety of benign tumors may involve the breast of the adolescent female. Neoplasms and cysts originating from the breast tissue itself, as well as from anatomically related tissues such as lymph nodes may occur. Imaging of the adolescent with a breast mass varies from that of the mature women because of the extremely uncommon occurrence of breast malignancy is this younger population. During a 22-year period (1978-99), 684 young females (14-20 years) were referred to the Breast Unit of the 1st Department of Obstetrics and Gynecology in the major University-appointed hospital of the University of Athens, because of breast masses. The clinical and imaging evaluation of the masses confirmed their presence in the majority of cases. Most cases (442-64.6%) were managed conservatively and carefully followed-up. In 242 cases (35.4%) ablation of the masses was performed. Biopsy showed 236 (97.5%) benign and 6 (2.5%) malignant tumors. The malignant tumors were 2 cases of hemangiosarcoma, 1 case of rhabdomyosarcoma, 1 case of ductual carcinoma, 1 case of cystosarcoma phylloides and 1 case of metastatic rhabdomyosarcoma from the eye. In three cases patients died as a consequence of the disease, two survived and one was lost due to the family's wishes to be transfered to another oncology department abroad.

Adolescent↗
PubMed1999

Oocyte morphology correlates with embryo quality and pregnancy rate after intracytoplasmic sperm injection.

OBJECTIVE: To evaluate the relation of oocyte morphology with embryo quality and pregnancy rates (PRs) after intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective study of patients undergoing ICSI. SETTING: University Hospital IVF Center. PATIENT(S): Sixty-eight patients who underwent ICSI and had transfer of good-quality embryos (grade 3), 60 patients with transfer of both good- and poor-quality embryos (grade 3 and grade 2), and 18 patients with transfer of poor-quality embryos (grade 2). INTERVENTION(S): Comparison of the outcome of ICSI in the three groups of patients and the relation of oocyte morphology to embryo quality. MAIN OUTCOME MEASURE(S): Oocyte morphology and embryo quality (grade). Fertilization, cleavage, and pregnancy rates. Serum E2 on the day of hCG administration. RESULT(S): Oocytes with poor morphology (dark cytoplasm; many vacuoles or fragments in cytoplasm) led to poor-quality embryos and consequently to lower PRs (5.5% versus 29.4%). Serum E2 on the day of hCG administration was significantly higher in the group with good-quality embryos compared with that with poor-quality embryos (2,047 +/- 135.7 versus 1,651 +/- 164.8 pg/mL, respectively). CONCLUSION(S): Serum E2 on the day of hCG administration is a marker of embryo quality. Oocyte morphology correlates well with embryo quality and PRs after ICSI.

Adult↗
PubMed1999

Laparoscopic treatment of massive ovarian edema.

Massive ovarian edema is an unusual cause of ovarian enlargement in young girls and women. A woman with the disorder was managed laparoscopically by wedge resection of the ovary. We believe that endoscopic surgery is the appropriate approach for ovarian edema, as it establishes the diagnosis by minimally invasive means and at the same time ensures conservative treatment.

Adult↗
PubMed1999

Pregnant women of 35 years of age or more: maternal serum markers or amniocentesis?

The aim of this prospective study was to compare triple test screening (alpha-fetoprotein, beta-chorionic gonadotrophin and unconjugated oestriol) with amniocentesis in the detection of fetuses with Down's syndrome in women of 35 years of age or more. Between 1992 and 1996, maternal serum markers were evaluated in 1406 women who had amniocentesis for prenatal diagnosis of chromosomal abnormalities related to a maternal age of 35 or more years. Sixteen fetuses with Down's syndrome were identified in the whole group by amniocentesis and karyotyping. The group with negative triple test screening consisted of 919 pregnancies and included two fetuses with trisomy-21 (false negatives). With triple test screening in the age group over 35, there was a detection rate of 87.5% for cut-off points ranging from 1:200 up to 1:350, with corresponding false positive rates ranging between 23% and 34%. In our population, if we had practiced the policy of offering amniocentesis only to women screening positive for the ages of 35 and 36 and to all pregnant women of 37 or more, we would have carried out 30% less amniocenteses. In this group of 1406 women, 33 abnormal karyotypes were detected with amniocentesis (16 Down's syndrome included) and equal number of elective abortions were carried out. Nevertheless, 19 healthy fetuses and neonates were lost after amniocentesis. Considering the high detection rates that can be achieved with triple test screening, the existing procedure related risk of amniocentesis (0.5-1.0%), and the facts that conception in women over 35 years of age is usually more difficult and the background loss usually higher than in younger women, we believe that in the future women over 35 should be offered a choice between non-invasive and invasive procedures after being thoroughly informed.

Journal Article↗
PubMed1999

Reduction of multifetal pregnancies to twins does not increase obstetric or perinatal risks.

Selective reduction in cases of multiple fetuses is used more often nowadays due to the increased number of multiple pregnancies resulting from assisted reproduction. In this retrospective study, we investigated whether twin pregnancies derived from fetal reduction carry a higher obstetric and perinatal risk compared to standard twin pregnancies. We found that the rate of miscarriage was 10.6% in the reduction group (n = 158) compared to 9.5% in the controls (n = 135). Mean gestational age at delivery was 35.7 weeks in the reduction group versus 35.1 weeks in the control group. Mean neonatal weight at birth was 2.260 g (800-3.750 g) in the reduction group compared to 2.240 g (540-3.360 g) in controls. Perinatal mortality rate was 49.3 per thousand after reduction and 42.0 per thousand in the control group. There was no statistically significant difference in any of the above parameters. Therefore, multifetal pregnancy reduction to twins does not appear to increase obstetric or perinatal risks.

Abortion, Spontaneous↗
PubMed1999

Detection and clinical correlations of ras gene mutations in human ovarian tumors.

In epithelial ovarian neoplasms K-ras codon 12 gene mutations show a wide variation fluctuating between 4-39% in invasive carcinomas and 20-48% in borderline malignant tumors. In this study, we showed the pattern of point mutations in codon 12 of the K-ras, H-ras and N-ras genes, using polymerase chain reaction restriction fragment length polymorphism analysis in 74 tissue specimens of Greek patients with epithelial ovarian tumors. K-ras and H-ras gene mutations were detected in 11/48 (23%) and 3/48 (6%) cases with primary invasive ovarian carcinomas, respectively, while N-ras gene mutations were not found. No mutation of K-, H- and N-ras genes was detected in 23 ovarian cystadenomas. In 1 out of 3 borderline ovarian tumors (33%) we found an H-ras gene mutation. The prevalence of mutations in K-ras gene was 1/8 (13%) in mucinous, 7/29 (24%) in serous, 1/3 (33%) in endometrioid and 2/8 (25%) in clear-cell adenocarcinomas and in H-ras gene 1/8 (13%) in mucinous and 2/29 (7%) in serous adenocarcinomas. Analysis of the results revealed no significant correlation between ras gene mutations and clinicopathological parameters or clinical outcome of this primary invasive ovarian carcinoma population. Our present data suggest that ras gene mutations in invasive ovarian carcinomas occur in 29% of Greek patients and are not associated with the differentiation of the epithelial cells or the response of patients to adjuvant platinum-based chemotherapy.

Adenocarcinoma↗
PubMed1999

Ovarian tumors during childhood and adolescence. A clinicopathological study.

Ovarian tumors during the first two decades of life represent the most frequent tumors of the female genital tract at this age. Clinical and therapeutical particularities differentiate them from the same tumors of older women. During the period 1993-1997, 57 ovarian tumors were diagnosed and managed in the Divisions of Pediatric and Adolescent Gynecology of the 1st and 2nd Departments of Obstetrics and Gynecology, University of Athens. Benign tumors were found to be 77.2%, malignant 15.8% and borderline 7%. Germ cell tumors were the most common 49.1%, epithelial 35.1%, stromal 12.3%, lymphoma 1.75% and mixed tumors 1.75%. Of all the malignancies germ cell carcinomas consisted of 44.5%.

Adolescent↗
PubMed1999

Genital tumors during childhood and adolescence. A clinical and pathological study of 71 cases.

Genital tumors during the first two decades of life are not common and they constitute 5-10% of all tumors. During the period 1993-1997, 71 cases of genital tumors were diagnosed and managed in the Divisions of Pediatric and Adolescent Gynecology of the 1st and 2nd Departments of Obstetrics and Gynecology, University of Athens. Ovarian tumors were found to be the most common uterine tumors -16.9% and cervical -28%. From the ovarian tumors -80.3% of all tumors; -77.2% of cases were found to be benign; 15.8% malignant and 7% borderline. Malignant tumors were found to be germ cell -44.5%, epithelial -22.2%, stromal -11.1%, lymphoma 11.1%, and mixed -11.1%.

Adolescent↗
PubMed1999

Day clinic diagnostic hysteroscopy in a state hospital.

Within 6 years (1991-97), a total of 680 diagnostic hysteroscopies were performed at the Day Clinic of the 1st Department of Obstetrics and Gynecology of the University of Athens ("Alexandra" Hospital). The procedure was done without general or other forms of anesthesia, using the Siegler method of approach. However in 12 cases with cervical stenosis (1.7%) and 21 patients with marked nervousness (3.1%) general anesthesia proved inevitable. The leading indication was repeated failure of IVF (54.7%), while other indications included abnormal bleeding, amenorrhea and oligomenorrhea, a history of abortions, and infertility. Abnormal hysteroscopic findings were observed in 276 cases (40.5%) among which intrauterine adhesions, endometrial hyperplasia and polyps were the most common. We had no major complications or fatalities in our series and hysteroscopy proved to be a very useful, accurate and safe method of assessing uterine and endometrial functional status.

Adult↗
PubMed1999

Does axillary dissection affect prognosis in T1 breast tumors?

BACKGROUND: The treatment of patients with breast cancer has undergone many revisions over recent decades. The current trend is toward limited resections and breast conservation. Some authors advocate the abandonment of axillary lymph node dissection (ALND) for small tumors. While it is accepted that ALND has no therapeutic effect in breast cancer patients, its prognostic significance for small tumors is debated. Eligibility criteria for surgical treatment without axillary dissection are evolving. METHODS: Considering that problem, we retrospectively reviewed the charts of 100 patients with T1 invasive carcinoma of the breast treated at Hippokration Hospital of Athens between 1986 and 1987. Patients were divided into two groups: those that underwent ALND (n=76) and those that did not (n=24). The following data were recorded: age, tumor size, grade, hormone receptor status and postoperative treatment. The ten-year overall and disease-free survival were analysed. A multivariate analysis was used to identify prognostic variables. RESULTS: There was no statistically significant difference in the ten-year overall and disease-free survival between the two groups. The univariate analysis showed that tumor size predicts both recurrence and survival. In the multivariate analysis tumor size was found to be an independent prognostic factor for overall survival. CONCLUSIONS: ALND did not influence the ten-year survival or the recurrence rate. Tumor size was the only statistically significant and independent prognostic factor for T1 breast cancer patients.

Adult↗
PubMed1999

How to avoid suboptimal management of cervical carcinoma by simple hysterectomy.

OBJECTIVE: To determine the reasons leading to an inappropriate simple hysterectomy in the presence of carcinoma of the cervix and to evaluate factors related to survival. METHODS: All preoperative information was abstracted from 63 cervical cancer patients cleared by simple hysterectomy from 1980-1993. Cervical cancer screening history as well as the indication for hysterectomy were analyzed. The 5-year survival was calculated and correlated with the tumour histological subtype and presumed stage of disease. RESULTS: The most common preoperative symptom was abnormal uterine bleeding (73%). The absence of preoperative cytology, an inadequately evaluated abnormal Pap smear and the failure to differentiate from endometrial carcinoma were the main causes leading to an inappropriate simple hysterectomy. The cumulative 5-year survival was 63.5% and was correlated with the presumed stage of disease and the histological subtype. CONCLUSION: Only with close adherence to the cervical cancer screening guidelines and appropriate evaluation of presenting symptoms can we avoid inappropriate management of cervical carcinoma with simple hysterectomy.

Adult↗
PubMed1999

The management of breech presentation in the last three decades.

In order to evaluate the changes in management of breech presentation during the last three decades, a retrospective analysis of the "Alexandra" Hospital records was undertaken. The years, 1965, 1975, 1985, 1995 and finally 1997 were used as pilot years for this purpose. The cesarean section, breech presentation and breech cesarean section rates were calculated for each year. Specific breech cesarean section rates in respect to birth weight and parity as well as perinatal mortality rates were also recorded for each pilot year. The overall cesarean section rate rose from 8.0% in 1965 to 25.2% in 1995 and 25.1% in 1997 while the breech cesarean rate climbed from 16.9% in 1965 to 74.1% in 1995 and 72.3% in 1997, irrespective of birth weight. A trend towards vaginal delivery of breeches in multiparous women till 1985 became less apparent in later years. During the same period, a marked decrease of the perinatal mortality rate was observed from 70.1/1000 in 1965 to 36.6/1000 in 1997. In conclusion, a more than four-fold increase of the breech cesarean section rate was apparently rewarded by a two-fold decrease in perinatal mortality.

Breech Presentation↗