PubMed Health⌕ Search

Biomedical subjects

H Kort

Publications and source records attributed to H Kort.

18 recordsLinked to original sources
PubMed2006

Analysis of the success and failure of endoscopic third ventriculostomy in infants less than 1 year of age.

OBJECTIVES: In infants less than 1 year of age, the value of endoscopic third ventriculostomy (ETV) is controversial. It is believed to cause more morbidity and to have higher failure rates. We analyzed our data enlarging the reported pool of ETV outcome in infants less than 1 year of age. MATERIALS AND METHODS: We performed 12 ETVs in ten patients younger than 1 year of age. All patients had predominant supratentorial hydrocephalus. We defined ETV success as a shunt-free follow-up of at least 12 months, however, allowing re-ETV. CONCLUSION: ETV should be considered as initial treatment and carries low morbidity in these infants. As the immune system rapidly matures, postponing shunt implantation for several months or even weeks would make an ETV procedure worthwhile. On the other hand, as success probability rapidly increases 4 months after birth, re-ETV should always be considered first.

Age Factors↗
PubMed1997

Prospective, randomized, double-blind study of high-dose aprotinin in pediatric cardiac operations.

BACKGROUND: Perioperative aprotinin decreases postoperative blood loss in adults undergoing cardiac operations, but its role is less clear in children. Therefore, a trial of aprotinin in pediatric cardiac operations was conducted to study the efficacy of its use in children. METHODS: Forty-two patients were randomly assigned to receive either high-dose aprotinin or placebo. Aprotinin efficacy was assessed using time from protamine administration to skin closure, postoperative blood loss and hemoglobin loss, and postoperative transfusion requirements. Measures of fibrinolysis (fibrin degradation product titers) and platelet preservation (beta-thromboglobulin levels) were also assessed. RESULTS: There were no statistically significant differences between groups in any of the blood loss or transfusion parameters. Fibrin degradation product levels, measured 4 hours postoperatively, had increased significantly for control patients, but remained unchanged for the aprotinin group (p < 0.02). beta-Thromboglobulin levels increased more rapidly during cardiopulmonary bypass in the control group (p = 0.03). CONCLUSIONS: Aprotinin appears to provide no clinical benefit in routine pediatric cardiac operations. A reduction in fibrinolysis, with perhaps an early preservation of platelet structure, is seen in the aprotinin group.

Aprotinin↗
PubMed1996

Preliminary experience with human oocyte cryopreservation using 1,2-propanediol and sucrose.

Feasibility of cryopreservation of mature human oocytes using 1, 2-propanediol and sucrose was studied initially utilizing 1 and 2 day old unfertilized oocytes. Of these 285 aged oocytes 55% survived thawing, and 41% of 128 oocytes inseminated by single sperm intracytoplasmic injection (ICSI) fertilized normally. Limited embryonic development occurred in 51% of these embryos (n = 27) observed for the next 4 days. Cryosurvival of fresh donated oocytes (n = 81) was poorer (n = 20; 24.7%), while fertilization (n = 13; 65%) and embryo development (100%) was good prior to uterine transfer on day 3. Eight oocyte recipient cycles were undertaken, in which cryopreserved donated oocytes were thawed and inseminated by ICSI. Five of these cycles reached embryo transfer, and three pregnancies were initiated though none went successfully to term. Oocyte cryopreservation will ultimately facilitate oocyte donation procedures; however, cryosurvival of fresh frozen oocytes must be improved to at least the degree observed with aged unfertilized oocytes.

Cell Survival↗
PubMed1991

Stimulation cycles suppressed with gonadotropin-releasing hormone analog yield accelerated embryos.

A retrospective study was performed to assess embryonic development and morphology in 71 patients whose follicular stimulation was regulated after down regulation with a gonadotropin-releasing hormone analog, leuprolide acetate. The embryos were compared with those from 66 patients who did not receive agonists and who were treated during the same period. A separate group of thawed embryos cryopreserved after down regulation in 21 patients was compared with embryos frozen after conventional stimulation during the same period from 21 other patients. Eleven morphological criteria were assessed in the fresh embryos, and analyses did not reveal any differences between the groups studied. However, the rate of development of embryos obtained during down-regulated cycles was significantly higher than that of embryos developing in conventional stimulation cycles. Although no significant morphological differences could be shown between the groups of cryopreserved embryos, there was a decreased incidence of implantation of embryos from patients who were exposed to analogs. It is suggested that embryos from down-regulated cycles should be cryopreserved earlier to correct for their accelerated development.

Clomiphene↗
PubMed1991

Poor implantation of cryopreserved reinsemination-fertilized human embryos.

OBJECTIVE: To investigate whether a poor rate of implantation after in vitro fertilization (IVF) was due to poor embryonic/endometrial synchrony during the original IVF cycle, we have cryopreserved reinseminated-fertilized embryos for later more synchronous replacement after thawing. The chance of implantation of fresh reinseminated fertilized human oocytes is approximately one tenth that of timely fertilized embryos. STUDY DESIGN AND DATA: Retrospective study of 35 original oocyte collections in which initial normal fertilization was 47.3% (129/273 oocytes), with 49.6% fertilization (67/135) upon reinsemination. Of these, 70 initially fertilized and 67 reinsemination-fertilized embryos were cryopreserved, and 50 initially fertilized and all 67 reinsemination-fertilized embryos were subsequently thawed with 72% and 63% cryosurvival, respectively, (not significant). SETTING: Private infertility clinic. RESULTS: In 11 cycles, 23 thawed initially fertilized embryos (group A) were replaced with a 21.7% implantation rate per embryo; in 10 cycles, 13 initially fertilized and 12 reinsemination-fertilized embryos (group B) were replaced together with an 8% implantation rate; finally, in 16 cycles, 30 reinsemination-fertilized embryos (group C) were replaced with a 3.3% implantation rate (group A versus group C: P = 0.076). Comparison of clinical pregnancies between these groups was significantly different (6/11 versus 1/16; P = 0.0427). CONCLUSION: Reinsemination-fertilized embryos survive freezing as well as initially fertilized embryos, but better embryonic/endometrial synchrony does not improve chances of their implantation.

Adult↗
PubMed1991

The Program for Public Psychiatry: state-university collaboration in Colorado.

A major focus of state-university collaboration programs in psychiatry has been providing services and manpower from the university to the public mental health system, which in turns provides valuable educational experiences to the university. The Program for Public Psychiatry, a state-university collaboration program in Colorado, was founded on a 25-year relationship between the department of psychiatry at the University of Colorado Health Sciences Center and the Colorado Division of Mental Health. The program has enabled Colorado's two state hospitals and most of its urban community mental health centers to almost completely fill previously vacant psychiatric positions. The collaboration has expanded to include programs for forensic psychiatry and developmental disabilities, as well as to fund educational and research missions in developing the public psychiatric work force.

Academic Medical Centers↗
PubMed1990

Immunosuppression supports implantation of zona pellucida dissected human embryos.

The effect of low dose immunosuppression with methylprednisolone during the first 4 days after oocyte retrieval on potential immune cell invasion of partially zona dissected embryos in utero was investigated in alternate in vitro fertilization patients (n = 32). The incidence of pregnancy was significantly higher in patients receiving methylprednisolone (7 of 18, 39%) than in control patients (1 of 14, 7%). Twenty-eight percent (11 of 39) of the embryos replaced in the corticosteroid treated patients implanted, whereas only 7% (2 of 31) of embryos in control patients had a fetal heart beat. There were no side effects reported in any of the patients receiving corticosteroids. It can be concluded that methylprednisolone supports implantation of embryos with small holes in their zonae. However, the actual mechanisms of corticosteroid support on the interaction between immune cells and micromanipulated embryos are not well understood.

Clinical Trials as Topic↗
PubMed1990

Observations on the morphology of pronuclei and nucleoli in human zygotes and implications for cryopreservation.

The effects of cryopreservation on human zygotes at various stages between the appearance of pronuclei and their close association were investigated. Pronuclear zygotes (n = 233) from 101 patients were frozen using propanediol 21-35 h following egg collection. The incidence of implantation of thawed pronuclear zygotes frozen 29-35 h following oocyte collection was significantly higher than that of younger pronuclear zygotes (28 versus 10%, respectively). Zygote age did not affect cell survival following cryostorage. The diameter and association of pronuclei and the number and distribution of nucleoli were determined from video tape recordings of 140 fresh zygotes. Pronuclear migration continued after pronuclear enlargement. The number of nucleoli remained constant during pronuclear migration, but their random distribution within the pronucleus diminished. Strongly adhered pronuclei had significantly more aligned nucleoli on adjacent sides than pronuclei which were still visually separated by ooplasm. This equatorial distribution of nucleoli was noted in the majority of zygotes older than 26 h. The findings suggest that zygote cryopreservation should be initiated when pronuclear migration is completed. This moment can be determined accurately by studying pronuclear association and nucleolar alignment.

Cell Nucleolus↗
PubMed1989

Partial zona dissection of human oocytes when failure of zona pellucida penetration is anticipated.

Partial zona dissection (PZD) of human oocytes facilitates sperm penetration through mechanically made holes in the zona pellucida. Only 1 of 69 eggs was damaged when sucrose was used to shrink the ooplasm during micromanipulation. The fertilization rate of micromanipulated oocytes in 18 couples with male factor infertility was 68% (34/50), which compared favourably with insemination of non-micromanipulated controls (21/45, 47%). PZD was advantageous in oligozoospermic patients, but not in cases of asthenozoospermia, combined semen problems or immunological infertility. Three twin and two singleton pregnancies resulted following replacement of 23 micromanipulated and eight control embryos in 14 patients. No differences in embryo morphology and development rates were found between the micromanipulated and control groups. The incidence of polyspermy in couples with abnormal semen analyses was relatively low (less than 20%) possibly due to partial activation of the oocytes following exposure to sucrose. Polyspermy was high (57%) in normozoospermic patients with either immunological infertility (n = 3) or failure of fertilization in previous cycles (n = 4). In the three immunological patients, nine of 11 hyaluronidase and sucrose-exposed control embryos fertilized and six implanted, possibly indicating that cumulus and corona cells are contributing factors inhibiting fertilization in such cases.

Embryo Transfer↗
PubMed1985

Human chorionic gonadotropin in the ectopic gestation.

The ectopic pregnancy is a relatively common condition in the south African black patients. The beta-specific subunit radioimmunoassay for human chorionic gonadotrophin (HCG) was utilized in procuring information in our series of 30 patients. Levels of the hormone were significantly lower when compared to normal gestation of similar duration, never exceeding 2000 mIU/ml. The clearance rate of HCG following normal vaginal delivery was about 24 h and less variable than that of ectopic gestation. The half-life clearance rate of HCG in the ectopics could be divided into three phases, suggestive of HCG compartmentalization. The possible buffering effect of this hormone in the maintenance of the receptor-saturated pregnancy is discussed. The possibility that the HCG produced by the normal pregnancy is dissimilar to that of ectopic is speculated upon.

Chorionic Gonadotropin↗
PubMed1980

Increased pregnancy rate with oil-soluble hysterosalpingography dye.

The diagnostic value of hysterosalpingography remains unquestioned. Previous studies have suggested that patients who underwent hysterosalpingography with an oil-soluble contract medium (OSCM) rather than a water-soluble contrast medium (WSCM) had higher subsequent fertility rates. This study evaluated subsequent fertility rates in 339 patients who underwent hysterosalpingography in which OSCM or WSCM was used. All forms of infertility were included and over-all, pregnancy occurred in the WSCM group in 21 of 162 patients (13%), in the OSCM group in 51 of 177 patients (29%); these rates were significantly different (P less than 0.001), with the unexplained infertility group and the male factor infertility group showing the most significant difference. Adverse effects of OSCM hysterosalpingography were not corroborated. For this reason it is suggested that initially the patient undergo hysterosalpingography with WSCM. Once patency has been established, 3 ml of OSCM should be injected as a therapeutic modality to increase subsequent fertility.

Clomiphene↗
PubMed1980

Microsurgical technique in the management of tubal ectopic pregnancy.

Microsurgical techniques employing fine instruments and suture, microelectrocautery and continuous lavage, and careful handling of tissue have been applied to a variety of gynecologic procedures in which the microscope itself is not warranted. The thesis underlying this practice is straightforward: if successful outcome in chronic tubal disease is enhanced by these procedures, then they may have a beneficial role in acute tubal disease. To test this premise, in the past 2 years nine patients with tubal ectopic pregnancies have been managed by microsurgical techniques at Yale-New Haven Hospital. Five of the ectopic pregnancies were unruptured and four were ruptured. The products of conception were removed either by meticulous debridement or linear antimesenteric salpingostomy in association with the microsurgical methods noted above. Tubal healing was by secondary intention. All patients were treated with prophylactic antibiotics and intra-abdominal low molecular weight dextran. Four months postoperatively, all tubes operated upon were patent by salpingography. Subsequently, three of the five women with unruptured pregnancies and two of the four with ruptured pregnancies achieved intrauterine pregnancies. However, one has spontaneously aborted. According to these preliminary results, microsurgical techniques may be beneficially applied in the treatment of selected cases of ectopic pregnancy.

Adult↗
PubMed1978

The intra-uterine contraceptive device--contraceptive or abortifacient?

Further to the investigation of the possible mode of action of the intra-uterine contraceptive device (IUCD), an assay for the beta-specific subunit of human chorionic gonadotrophin (HCG) has detected endogenous chorionic activity 21 days after menstruation. In 22 proven ovulatory cycles, 7 patients wearing an IUCD had demonstrable serum HCG levels in 45% of these cycles. Abnormal menstruation was associated with the majority of cycles in which there was HCG in the serum. Subsequent luteolysis occurred in all cases. The results of this study may support the hypothesis that IUCD exerts its effect on the fertilized, implanted blastocyst, thus causing possible 'micro-abortion'. Caution should be exercised in the interpretation of HCG values in the follow-up of patients with hydatidiform mole or choriocarcinoma who are bearing IUCDs, since positive HCG levels may be due to an early, fertilized and implanted blastocyst and not to invasive tissue.

Adult↗
PubMed1978

An analysis of the first 200 legal abortions at the Johannesburg General Hospital.

A retrospective study was made of the first 200 terminations of pregnancy at the Johannesburg General Hospital since the promulgation of the Abortion and Sterilization Act of 1975. The indications for termination of pregnancy, the ages, marital status and parity of the patients, the procedures and their complications are analysed. Psychiatric factors were cited in 76% of cases. Further indications were rubella infection in the first trimester of pregnancy, medical, genetic and legal factors. The use of intra- and extra-amniotic prostaglandin administration is compared.

Abortion, Legal↗