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Biomedical subjects

J Smitz

Publications and source records attributed to J Smitz.

At least 91 records · Page 5Linked to original sources

Concentrations of chemical mediators in nasal secretions after nasal allergen challenges in atopic patients.

By using a microsuction technique, a quantitative determination of chemical mediators in nasal secretions was performed in 18 hay-fever patients and in a control group of 10 healthy volunteers. The authors then compared these quantitative data for mediators with objective nasal findings counting the number of sneezes, passive anterior rhinomanometry (PAR) and nasal inspiratory peak flow. A sampling protocol was designed with a follow-up of 3 days after nasal allergen challenge (NAC) in order to investigate both early and late allergic reactions. Median baseline concentrations of five major mediators were obtained: histamine, 19 ng/g; leukotriene C4 (LTC4), 5.7 ng/g. tryptase, 0; prostaglandin D2 (PGD2), 477 pg/g; eosinophil cationic protein (ECP), 105 ng/g. Significant increases in histamine (214 ng/g), LTC4 (20 ng/g) and tryptase (28 microU/g) were found, but a significant decrease occurred in ECP (47 ng/g) and PGD (226 pg/g) immediately after NAC in the patients studied. Most ECP concentrations (94%) increased slowly 1 h after NAC and reached a significantly higher level 24 h later. In evaluating nasal symptoms, sneezes were present in a high percentage of cases (76%) during the early phase but were uncommon during the late phase (29%). Total nasal obstruction occurred in 94% during the early phase. In contrast, unilateral nasal obstruction presented in 82% during the late phase, whereas total nasal obstruction was present only in 41%. The most common type of late phase nasal obstruction shown by PAR was alternating nasal obstruction.

Adolescent↗

Prepubertal acne: a cutaneous marker of androgen excess?

BACKGROUND: Early-onset acne before obvious signs of puberty is an uncommon phenomenon. OBJECTIVE: The aim of this study was to determine if prepubertal acne is associated with an excess of androgens. METHODS: Basal and adrenocorticotrophic hormone-stimulated plasma androgen levels were measured and bone age was determined in 15 children with early-onset acne. RESULTS: A late-onset adrenogenital syndrome caused by 21-hydroxylase deficiency was diagnosed in two children. These children had early pubic hair development and advanced bone maturation. Heterozygosity for 21-hydroxylase deficiency was found in three other children. CONCLUSION: We recommend hormonal evaluation in children with prepubertal acne, especially those with associated advanced bone maturation and early pubarche.

17-alpha-Hydroxyprogesterone↗

Intracytoplasmic sperm injection (ICSI): the Brussels experience.

The present report covers the results of a 26-month period in which 1275 consecutive treatment cycles by intracytoplasmic sperm injection (ICSI) were performed in 919 couples. These couples were afflicted with male factor infertility and had had at least one previous failed conventional in vitro fertilization (IVF) treatment cycle. In other couples, the husband had semen parameters incompatible with conventional IVF or suffered from excretory azoospermia which required microsurgical epididymal sperm aspiration or testicular sperm retrieval. Overall, the 2 pronuclear (PN) fertilization rate was 47.7% per retrieved oocyte-cumulus complex and 66.4% per successfully injected metaphase II oocyte. Embryo transfer was performed in 90.8% of started cycles and 362 clinical pregnancies were recorded, giving a clinical pregnancy rate of 28.4% per started cycle or 31.3% per transfer. In addition, updated results on the outcome of pregnancies after microassisted fertilization are presented. As of 30 August 1994, 416 children have been born. Although 16 major congenital malformations have been observed (3.9%), there appears to be no reason for serious concern as regards the occurrence of major congenital anomalies after ICSI.

Belgium↗

Pregnancy and birth after high serum progesterone concentrations during the follicular phase in an in-vitro fertilization cycle with gonadotrophin-releasing hormone agonist suppression.

This case illustrates the possibility of achieving a pregnancy and birth when elevated progesterone concentrations (> 4 ng/ml) are present during the follicular phase (from 6 days before human chorionic gonadotrophin injection) of a gonadotrophin-releasing hormone agonist/menotrophin cycle for in-vitro fertilization (IVF). The present patient underwent three IVF/embryo transfer cycles in which progesterone concentrations were repeatedly increased from the midfollicular phase onwards. A pregnancy was achieved after the first IVF attempt but ended in a miscarriage in the 19th week of gestation. During the second IVF attempt an endometrial biopsy taken on the day of oocyte retrieval revealed an endometrial advancement of 2 days. A successful pregnancy and birth was again achieved after the third IVF attempt although progesterone concentrations were considerably increased from 6 days before the ovulatory stimulus.

Adult↗

Oocyte and embryo quality as well as pregnancy rate in intracytoplasmic sperm injection are not affected by high follicular phase serum progesterone.

The effect of elevated serum progesterone concentrations (> 1 ng/l) on or before the day of human chorionic gonadotrophin (HCG) injection on the outcome of women receiving gonadotrophin-releasing hormone analogue (GnRHa)/human menopausal gonadotrophin (HMG) for ovarian stimulation prior to intracytoplasmic sperm injection (ICSI) was evaluated. A total of 1275 ICSI cycles were analysed retrospectively. In 53 cycles (4.5%), serum progesterone concentrations were > 1 ng/ml. Patients in the high progesterone group had significantly higher oestradiol and luteinizing hormone concentrations on the day of HCG injection. The characteristics of the cumulus-corona cell complexes and the nuclear maturity of the oocytes were similar in the groups of patients with high and low serum progesterone levels. Fertilization and cleavage rates as well as embryo quality were not different in the two groups. No difference in implantation or clinical pregnancy rates was observed between the high progesterone and low progesterone groups. Moreover, the cumulative exposure to progesterone during the follicular phase, as expressed by the area under the curve (AUC), and the duration of exposure to high serum progesterone levels (> 1 ng/ml) were not significantly different between pregnant and non-pregnant women in the high progesterone group. We conclude that in ICSI cycles pretreated with GnRHa, increased serum progesterone concentrations on or before the day of HCG injection do not affect ICSI outcome.

Adult↗

A randomized, assessor-blind, group-comparative efficacy study to compare the effects of Normegon and Metrodin in infertile female patients undergoing in-vitro fertilization.

A randomized, assessor-blind, group-comparative study was performed to compare the efficacy of Normegon [75 IU follicle stimulating hormone (FSH) and 25 IU luteinizing hormone (LH) and Metrodin (75 IU FSH and < 1.25 IU LH) in infertile women undergoing in-vitro fertilization (IVF) and embryo transfer. None of the patients were pituitary-suppressed by means of gonadotrophin-releasing hormone (GnRH)-agonist treatment. They were randomized in blocks of five with a ratio between treatment with Normegon and with Metrodin of 3:2. A total of 158 patients started hormonal treatment, i.e. 93 patients with Normegon and 65 patients with Metrodin and a total of 248 cycles were performed. Evaluation of first treatment cycles included statistical analysis of the total number of ampoules, number of follicles (> or = 14 mm), serum oestradiol concentrations on the day of HCG (10,000 IU) administration, the number of oocytes retrieved and the ongoing pregnancy rate per attempt and per transfer. For none of these parameters were significant differences revealed. In both groups the median duration of stimulation was 7 days and the median number of ampoules used was 21. Overall, the duration of treatment was short in order to prevent as much as possible endogenous LH rises. The overall ongoing pregnancy rate per transfer of all cycles was 21% in the Normegon group and 19% in the Metrodin group. Analysis of completed treatment cycles (n = 90) with premature rises of LH > 10.0 IU/l and/or progesterone > 1.0 ng/l revealed a relatively high incidence (23%) of fertilization failure and poor embryo quality, but the ongoing pregnancy rate per transfer was still 22%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Comparison among different ovarian stimulation regimens for assisted procreation procedures in patients with endometriosis.

The objective of our study was to establish the most adequate ovarian stimulation regimen for assisted procreation in endometriotic patients. It consisted of a retrospective analysis comparing the use of the gonadotrophin-releasing hormone analogue (GnRHa) buserelin either for 3 months or for 3 weeks and continued with ovarian stimulation with human menopausal gonadotrophin (HMG), and the use of clomiphene citrate in association with HMG for in-vitro fertilization (IVF) and embryo transfer, gamete intra-Fallopian transfer (GIFT) and zygote intra-Fallopian transfer (ZIFT). A total of 145 patients with endometriosis in 174 cycles were divided into two groups according to the revised American Fertility Society staging of the disease (group A, stages 1 and 2; group B, stages 3 and 4). The use of GnRHa significantly increased the number of oocytes retrieved. GnRH analogues for 3 months gave the highest fertilization rate for groups A and B. The cleavage, pregnancy and delivery rates, although higher in the groups treated with analogues, did not reach statistical significance. A higher number of patients had an embryo transfer in the groups treated with GnRHa (P < 0.05). Treatment with GnRHa for either 3 months or for 3 weeks proved to be more efficient than clomiphene citrate-HMG for assisted procreation procedures in patients with endometriosis.

Adult↗

Prostaglandin D2 measurement in nasal secretions is not a reliable marker for mast cell activation in atopic patients.

BACKGROUND: Prostaglandin D2 (PGD2) is a very important mast cell product during the early-phase nasal allergic reaction. However, the quantification of PGD2 in nasal secretions has not yet been well established. OBJECTIVE: Quantitative determination of PGD2 in nasal secretions of atopic patients (n = 17) after nasal allergen challenge (NAC) and in non-allergic healthy volunteers (n = 10). METHODS: The nasal microsuction sampling technique was used to obtain the nasal secretions with an exactly known and minimally diluted volume. A sensitive and specific enzyme immunoassay was chosen to measure the more stable 11-methoxime derivative of PGD2, which was obtained after extraction in acetone/ethanol and conversion using methoxamine-HCl. The concentrations of PGD2 in nasal secretions obtained from 10 non-allergic healthy volunteers were used as reference values. RESULTS: There was no significant difference in the concentrations of PGD2 between men (median: 569 pg/mL) and women (median: 407 pg/mL), nor between the baseline concentrations from atopic patients (median: 410 pg/mL) and non-allergic controls (median: 477 pg/mL). In the atopic patient group, PGD2 did not significantly increase during the entire sampling period after NAC. The absence of PGD2 response contrasted with the nasal symptoms manifested by sneezing, increased nasal airway resistance, and the significant increases of the concentrations of histamine, tryptase, and leukotriene C4 (LTC4) 5 min after NAC. CONCLUSION: This observation suggests that the measurement of PGD2 alone in the nasal secretions does not give reliable information on mast cell activation during a nasal allergic reaction.

Adolescent↗

Monitoring nasal allergic inflammation by measuring the concentration of eosinophil cationic protein and eosinophils in nasal secretions.

Quantitative measurement of the eosinophil cationic protein (ECP) concentration and the percentage of eosinophils in nasal secretions has greatly improved our understanding of the inflammatory process after natural allergen exposure. ECP and eosinophils were measured in the nasal secretions of 40 symptomatic patients with seasonal allergic rhinitis during the pollen season. Results showed a significant relationship between a high concentration of ECP (median: 410 ng/g, range: 6-2380 ng/g) and a high percentage of eosinophils (median: 13.5%, range: 1-85%). This quantitative study again demonstrated that infiltration by eosinophils and release of ECP play a key role in allergic rhinitis. It also suggests that the combined measurement of the percentage of eosinophils together with the ECP concentration in nasal secretions seems to be a very useful model in monitoring and assessing the condition of chronic nasal inflammation in patients with allergic rhinitis.

Adolescent↗

Correlations between complaints, inflammatory cells and mediator concentrations in nasal secretions after nasal allergen challenge and during natural allergen exposure.

A quantitative determination of the inflammatory mediators was performed and correlated with complaints and the measurement of the inflammatory cells in nasal secretions of 18 seasonal allergic rhinitis patients (group 1) outside the pollen season and 40 symptomatic patients (group 2) with seasonal allergic rhinitis during the pollen season. Ten nonallergic subjects (group 3) were also studied as a normal control group. In group 1, 17 (94%) out of 18 patients had an immediate response of nasal symptoms accompanied by a significant increase of histamine, leukotriene C4 (LTC4), and tryptase 5 min after nasal allergen challenge (NAC). One hour later, a simultaneous increase was seen both in the percentage of the eosinophils and in the eosinophil cationic protein (ECP) concentration. The eosinophil count reached a peak 2 h after NAC with a duration of 8 h, while the highest ECP level was reached only after 24 h with no clear-cut plateau. In group 2, a high percentage of eosinophils was observed. Mostly one observed significantly (p < 0.01) higher concentrations of ECP, LTC4 and histamine but not of tryptase than the baseline values of group 1. The authors concluded that during the pollen season allergic rhinitis reflects mainly a chronic state of allergic inflammation of the nasal mucosa involving various inflammatory components induced by one or more episodes of early-phase type allergic reaction. Infiltration of eosinophils and consequently release of the various late-phase inflammatory mediators into the nasal secretions are certainly believed to be the predominant pathophysiologic condition in the patients.

Adolescent↗

Analysis of 76 total fertilization failure cycles out of 2732 intracytoplasmic sperm injection cycles.

From October 1992 to December 1994, 2732 cycles of treatment by intracytoplasmic sperm injection (ICSI) were carried out in couples mainly with severe male-factor infertility. The overall fertilization rate in these 2732 cycles was 71% of intact oocytes. However, in 76 (72 couples) of these cycles, none of the injected oocytes became fertilized, so the total fertilization failure rate was 3% (76/2732 cycles). Details of these 76 cycles were analysed. The results show that total fertilization failure after ICSI may be explained by different factors related to (i) semen characteristics (only immotile or round-headed spermatozoa for ICSI) or (ii) the oocytes (number, abnormal morphology, damage after ICSI). Of 26 couples, 22 achieved fertilization in their subsequent ICSI cycles. In conclusion, total fertilization failure after ICSI for the treatment of severe male-factor infertility was mainly caused by the poor viability of the spermatozoa used for injection; it was also associated with a low number and poor quality of oocytes. Repeated ICSI treatment may be useful or necessary in couples with total fertilization failure.

Adult↗

Fetal hypothyroidism as a complication of amiodarone treatment for persistent fetal supraventricular tachycardia.

We present a case of persistent fetal supraventricular tachycardia where transplacental and direct fetal treatment with amiodarone caused an iatrogenic hypothyroidism. This condition was successfully managed with the intra-amniotic instillation of 250 micrograms of L-thyroxine weekly, for 3 weeks. A male infant was delivered at 32 weeks by Caesarean section. The neonatal electrocardiogram showed Wolf-Parkinson-White (WPW) syndrome, which was controlled by digoxin alone. Thyroid function normalized quickly and the baby is developing normally.

Adult↗

Intracytoplasmic sperm injection.

Intracytoplasmic sperm injection (ICSI) is a promising assisted fertilization technique that may benefit women who have not become pregnant by in-vitro fertilization. ICSI and subzonal insemination (SUZI) were used to treat couples who failed fertilization after standard IVF or who could not be accepted for IVF because too few motile spermatozoa were present in the ejaculate. This paper describes the outcome of 750 consecutive cycles of SUZI and ICSI. Different aspects of these novel assisted fertilization procedures are described: patient management, ovarian stimulation, semen evaluation and treatment, oocyte collection and preparation, SUZI and ICSI techniques, assessment of fertilization and embryo cleavage, outcome of embryo transfers and the evolution of the pregnancies.

Embryo Transfer↗

Human endometrial maturation is markedly improved after luteal supplementation of gonadotrophin-releasing hormone analogue/human menopausal gonadotrophin stimulated cycles.

In human cycles stimulated for ovulation with gonadotrophin-releasing hormone (GnRH) agonists and human menopausal gonadotrophin (HMG), a luteal phase defect has been described. To evaluate the influence on the endometrium, endometrial development in GnRH agonist/HMG stimulated cycles was assessed in cycles with and without luteal phase supplementation. Endometrial histological maturation, ultrastructure and oestrogen receptor (ER) and progesterone receptor (PR) status were analysed in the mid-luteal phase. Serum concentrations of oestradiol and progesterone were measured daily from days 1-5 of the luteal phase. Supplementation of the luteal phase was achieved with either human chorionic gonadotrophin or natural progesterone, administered intramuscularly or intravaginally. In non-supplemented cycles all endometrial features were consistent with an impaired progesterone bioavailability. After supplementation of the luteal phase, fewer signs of luteal phase deficiency were visible, especially with the intravaginal route of progesterone administration. We concluded that the endometrial parameters confirm the need for luteal support in GnRH agonist/HMG stimulated cycles.

Adult↗

Clinical outcome of a pilot efficacy study on recombinant human follicle-stimulating hormone (Org 32489) combined with various gonadotrophin-releasing hormone agonist regimens.

In total, 50 couples participated in a pilot study evaluating the efficacy of various regimens of gonadotrophin-releasing hormone agonist (GnRHa) in association with recombinant human follicle-stimulating hormone (recFSH) in women undergoing in-vitro fertilization (IVF) and embryo transfer. The women were treated with recFSH alone (group I), or with recFSH in conjunction with pituitary desensitization using a buserelin intranasal spray, 4 x 150 micrograms per day, in a short protocol (group II) or in a long protocol (group III), or using triptorelin in a long protocol, giving a single dose of 3.75 mg i.m. (group IV) or daily s.c. injections of 200 micrograms (group V). In all women, treatment with recFSH resulted in multiple follicular growth and rises of serum inhibin and oestradiol. The latter indicates that the amount of remaining luteinizing hormone (LH) was sufficient to support FSH-induced oestrogen biosynthesis. On the day of human chorionic gonadotrophin (HCG) administration, endogenous LH was most profoundly suppressed in subjects treated with triptorelin. The median number of ampoules and treatment days required in the various treatment groups varied from 21 to 36 ampoules and from 7 to 14 days, respectively. The median number of oocytes per group ranged from 9 to 11 and all cumulus-corona-oocyte complexes, with the exception of two, were classified as mature. The median fertilization and cleavage rates ranged between the treatment groups from 40 to 73% and from 73 to 100%, respectively. Fertilization failure of retrieved oocytes occurred in six couples with andrological or unexplained infertility. One patient had no transfer because of insufficient embryo quality.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Concentrations of chemical mediators in nasal secretions of patients with hay fever during natural allergen exposure.

By using the microsuction technique, quantitative determination of the chemical mediators in nasal secretions was performed in 40 patients with seasonal allergic rhinitis during the pollen season. The aim of this study was to investigate the actual concentrations of these important mediators in nasal secretions during natural allergen exposure so as to better understand the pathophysiology of allergic rhinitis. The median concentrations of four mediators, were histamine: 51.5 ng/g (range: 4-146 ng/g); tryptase: 0 (range: 0-84 microU/g); leukotriene C4 (LTC4): 23 ng/g (range: 11-77 ng/g); and eosinophil cationic protein (ECP): 410 ng/g (range: 6-2380 ng/g). The authors compared these concentrations with those of the same mediator found in a previous study of seasonal allergic rhinitis patients after nasal challenge outside the pollen season. The present study demonstrates that during the season allergic rhinitis reflects a chronic state of allergic inflammation of the nasal mucosa involving various inflammatory mediators induced by one or more episodes of early type allergic reaction.

Adolescent↗

The use of recombinant FSH for ovulation induction.

Recombinant human FSH (recFSH) was tested in a phase II study in 50 couples superovulated for IVF. Rec FSH alone was used in 10 women (Group 1). Intranasal buserelin spray (150 micrograms x 4 daily) was used in a flare-up protocol (10 women; Group 2) or in a desensitization protocol (10 women; Group 3) in combination with rec FSH. Desensitization using Triptorelin depot (3.75 mgIM) followed by rec FSH was given to 10 women (Group 4), while the same agonist was used subcutaneously (200 micrograms/daily) in Group 5 (10 women). In the five groups rec FSH induced multiple follicular growth. Significantly more ampoules rec FSH were required when a GnRH agonist was used. I all groups 9 to 11 mature oocytes were retrieved per cycle. In 6 couples there was an absence of fertilization due to severe sperm anomalies (5 couples); one couple suffered from idiopathic infertility. Fertilization and cleavage was normal in 44 couples. Forty-three transfers of 2.3 to 2.8 embryos yielded 10 pregnancies. Nine healthy babies were born. Superovulation for IVF was successful and safe by using rec FSH alone or in combination with various GnRHa dosages and protocols.

Buserelin↗

A prospective randomized study on oestradiol valerate supplementation in addition to intravaginal micronized progesterone in buserelin and HMG induced superovulation.

A prospective randomized study was conducted to evaluate the use of adding oestradiol valerate 6 mg per os daily to intravaginal micronized progesterone (600 mg daily) as luteal supplements. The study comprised 378 infertile women superovulated with a gonadotrophin releasing-hormone agonist (GnRHa) and human menopausal gonadotrophins (HMG) for in-vitro fertilization (IVF) or zygote intra-Fallopian transfer (ZIFT). The clinical pregnancy rate was similar (29%) whether or not oestradiol valerate was added to intravaginal progesterone. Eighteen out of twenty-two endometrial biopsies were in phase, and morphological evaluations of the two luteal supplementation groups were not different. Serum hormone profiles in singleton pregnancies showed a similar day of appearance of human chorionic gonadotrophin (HCG) in both protocols but significantly lower oestradiol concentrations arose in the group without oestradiol valerate. In 32% of the singleton pregnancies, the first appearance of HCG occurred later than day 12 after HCG injection; in those ongoing pregnancies, corpus luteum rescue--as measured by significantly lower serum oestradiol and progesterone concentrations--was compromised. This study provided no evidence of any benefit of routinely supplementing GnRHa/HMG cycles with oestradiol valerate in addition to intravaginal micronized progesterone.

Administration, Intravaginal↗