[Pathological changes of the chemosensory function in multiple sclerosis - an MRI study]

PURPOSE

To examine possible causes for olfactory and gustatory dysfunction in MS patients in a prospective study with MRI.

MATERIALS AND METHODS

30 MS patients (21 women, 11 men, 22 - 65 years, Ø 42 years) were examined by MRI. The olfactory bulb (OB) and olfactory brain volume was correlated with the number and volume of MS lesions in the olfactory brain and the non-olfactory brain. Olfactory testing was performed using the Threshold-Discrimination-Identification Test (TDI), and gustatory function was tested using the Taste-Strips-Test (TST).

RESULTS

33 % of the MS patients displayed olfactory dysfunction (8 % of the control group), and 17 % displayed gustatory dysfunction (5 % of the control group). There was a correlation between the olfactory brain volume and the number (r = -0.38, p < 0.05) and volume (r = -0.38, p < 0.05) of MS lesions in the olfactory brain. The olfactory brain volume correlated with the number of MS lesions in the non-olfactory brain (r = -0.48, p < 0.05). The volume of the left OB correlated with the volume of MS lesions in the olfactory brain (r = -0.42, p < 0.05), the number (r = 0.37, p < 0.05) and volume (r = 0.4, p < 0.05) of lesions in the left part of the olfactory brain and with the TST score (r = -0.45, p < 0.05). The TST score correlated with the volume of lesions in the left (r = -0.45, p < 0.05) and right part (r = -0.53, p < 0.05) of the olfactory brain. The TST score correlated with the number of lesions in the non-olfactory brain (r = -0.48, p < 0.05).

CONCLUSION

The correlation between a higher number and volume of MS lesions in the olfactory brain with a decreased OB and olfactory brain volume could help to explain olfactory and gustatory dysfunction in MS patients. Just the left OB correlated with the number and volume of lesions in the olfactory brain. Manual segmentation was a suitable method for measuring OB and olfactory brain volume.

Effects of recombinant LH treatment on folliculogenesis and responsiveness to FSH stimulation

BACKGROUND

The role of LH in sensitizing antral follicles to FSH is unclear. LH is required for normal hormone production and normal oocyte and embryo development, but follicular responses to LH may depend upon the stage of development. Potential roles at the early follicular phase were explored in a clinical setting by employing a sequential approach to stimulation by recombinant human (r-h) LH followed by r-hFSH in women who were profoundly down-regulated by depo GnRH agonist.

METHODS

We employed a multi-centre, prospective, randomized approach. Women (n = 146) were treated in a long course high-dose GnRH agonist (Decapeptyl, 4.2 mg s.c.) protocol and were randomized to receive r-hLH (Luveris, 300 IU/day) for a fixed 7 days, or no r-hLH treatment. This was followed by a standard r-hFSH stimulation regime (Gonal-F, 150 IU/day). Ultrasound and hormone assessments of responses were measured at the start of r-hLH treatment, on FSH stimulation Days 0 and 8 and at the time of HCG administration.

RESULTS

The LH treatment was associated with increased small antral follicles prior to FSH stimulation (P = 0.007), and an increased yield of normally fertilized (2 PN) embryos (P = 0.03). There was no influence of the r-hLH pretreatment upon hormone profiles or ultrasound assessments during the FSH phase. Anti-mullerian hormone increased in both groups during the week prior to FSH stimulation (P = 0.002).

CONCLUSIONS

This sequential approach to the use of r-hLH in standard IVF showed a possible modest clinical benefit. The results support other recent work exploring up-regulated androgen drive upon follicular metabolism indicating that clinical benefit may be obtainable after further practical explorations of the concept.

Malformation rate and sex ratio in 412 children conceived with epididymal or testicular sperm

BACKGROUND

Follow-up studies of children conceived after ICSI using epididymal or testicular sperm are important due to a still more extensive use of immature male germ cells for ICSI. It is, however, difficult to evaluate the potential risks of malformations of children born after ICSI, overcoming the natural fertilization processes, due to methodological limitations.

METHODS

Follow-up study including all children born in Denmark and Norway following ICSI in Denmark, using epididymal or testicular sperm, was done. A questionnaire was sent to the parents between 3 months and 7 years after delivery.

RESULTS

Of 341 couples, 329 returned the questionnaire giving a response rate of 96.5%. The study included 412 children, 225 girls and 187 boys, giving a sex ratio (males/males + females) of 45.4% compared with 53.1% in Danish children conceived after conventional IVF without ICSI (P < 0.005). Among a total of 14 (3.4%; 95% confidence interval (CI): 1.9%-5.7%) major malformations, three boys with hypospadias were the most remarkable finding (1.6%; 95% CI: 0.33-4.7%).

CONCLUSIONS

An increased frequency of hypospadias in the male offsprings was seen compared with the general population. Apart from this, no increased major malformation rate was detected in ICSI children conceived with epididymal or testicular sperm when compared with malformation rates for IVF or spontaneously conceived children reported in the literature. The sex ratio was significantly lower for ICSI children conceived with epididymal or testicular sperm when compared with children conceived with conventional IVF.

Register data on assisted reproductive technology (ART) in Europe including a detailed description of ART in Denmark

The European Society for Human Reproduction and Embryology (ESHRE) has monitored Assisted Reproduction in Europe since 1997. In 2001, 579 clinics from 23 countries reported 289,690 treatment cycles with: in vitro fertilization (IVF) 120,946, intracytoplasmatisk sperm injection (ICSI) 114,378, frozen embryo replacements (FER) 47,195 and egg donation (ED) 7,171. Intrauterine inseminations are less consistently reported, but in 2001, 15 countries reported 67,124 cycles (IUI-H 52 949 and IUI-D 14 185). Data from 2001 showed that in 12 countries, where all clinics reported the in vitro techniques to the register, 829 treatment cycles were performed per million inhabitants. The availability was highest in the Nordic countries (range 975-1,923 cycles). The proportion of infants born after ART with in vitro techniques ranged from 0.2% in Latvia to 3.9% in Denmark. In general, the impact of the in vitro techniques on the birth rate is highest in the Nordic countries (range 2.2-3.9%). Denmark is the only country with an established National ART reporting system involving all ART treatments both with the in vitro techniques and intrauterine inseminations. In the year 2002, a total of 20,837 treatment cycles were performed. The result was that 6.2% of all infants were born after assisted reproduction.

The role of Gilbert's syndrome and frequent NAT2 slow acetylation polymorphisms in the pharmacokinetics of retigabine

Retigabine (RGB) is an investigational antiepileptic drug, which undergoes extensive UGT1A1, 1A9 and 1A4-mediated N-glucuronidation and N-acetylation. The mono-acetylated metabolite of RGB has some pharmacological activity and is denoted AWD21-360. We investigated whether the pharmacokinetics (PK) of RGB and AWD21-360 are altered in subjects with Gilbert's syndrome (GS) and/or with frequent N-acetyltransferase 2 (NAT2) slow acetylator (SA) polymorphisms. Based on consistent genotyping and phenotyping screening results, 37 Caucasian subjects (21-46 years; 31 men, six women) were assigned to one of the following groups: (1) absence of GS (non-GS)/rapid acetylator (RA) (N=11); (2) GS/RA (N=8); (3) non-GS/SA (N=11); (4) GS/SA (N=7). Subjects received single and multiple (b.i.d.) 200-mg oral RGB doses over 5 days. Blood samples were collected up to 60 h after dosing for plasma PK of RGB and AWD21-360. Group comparisons were performed by ANOVA. Single-dose PK of RGB and AWD21-360 and multiple-dose PK of RGB did not differ significantly between groups. After multiple dose treatment, RA subjects showed a significantly higher total exposure to AWD21-360 of about 32% (95% CI 101.9-172.5) relative to SA subjects (P=0.0362). The UGT1A1 metabolic capacity (i.e. presence or absence of GS), however, did not significantly affect the overall exposure to AWD21-360. The results indicate that the PK of RGB is unaltered in individuals with GS, in subjects with NAT2 SA status, and in carriers of both variants, whereas the total exposure to AWD21-360 is significantly related to the RA or SA status of subjects. Results further suggest that metabolic switching to the mono-acetylated metabolite AWD21-360 may partially compensate for the impaired glucuronidation capacity in GS subjects. RGB treatment showed no significant differences in tolerability and safety between groups.

Impact of follicular-fluid meiosis-activating sterol in an albumin-based formulation on the incidence of human pre-embryos with chromosome abnormalities

OBJECTIVE

To evaluate the effect of adding follicular-fluid meiosis-activating sterol (FF-MAS) in a novel 0.2% recombinant human albumin-based formulation to cumulus-enclosed oocytes on chromosomal status and development of pre-embryos.

DESIGN

Multicenter, prospective, randomized, open (double-blind for vehicle and FF-MAS groups), four parallel groups, controlled trial.

SETTING

Four public IVF clinics in Denmark.

PATIENT(S)

Two hundred eighteen women undergoing IVF donated 483 oocytes.

INTERVENTION(S)

Follicle-stimulating hormone/hCG-primed cumulus-enclosed oocytes randomized to 4 hours of exposure to medium with 1 or 10 micromol/L of FF-MAS dissolved in 0.2% recombinant human albumin, medium with 0.2% recombinant human albumin (vehicle control), or medium alone (control) before insemination.

MAIN OUTCOME MEASURE(S)

Primary endpoint: incidence of human pre-embryos with chromosomal abnormalities. Secondary endpoint: fertilization rate, cleavage rate, and pre-embryo quality assessed after 68 hours of culture.

RESULT(S)

At pre-embryo level, the overall abnormality rates in the control, vehicle control, and 1- and 10-micromol/L FF-MAS groups were 53%, 39%, 42%, 53%, respectively, and at blastomere level 49%, 44%, 44%, and 48%, respectively. After 20 and 26 hours, the fertilization rates were between 67% and 71% in all groups. No differences in the cleavage rates were observed.

CONCLUSION(S)

The concentrations of FF-MAS in a novel 0.2% recombinant human albumin-based formulation of FF-MAS did not increase the risk of chromosomal abnormalities in pre-embryos or blastomeres. No statistically significant differences in fertilization rate, cleavage rate, or number of good quality pre-embryos were found among the four groups.

Neue Richtlinien für die Beurteilung der Bioverfügbarkeit/Bioäquivalenz

Bioavailability and bioequivalence studies are essential in the clinical development of medicinal products and the optimization of pharmaceutical forms. Bioavailability means the rate and extent to which the active substance or active moiety is absorbed from a pharmaceutical form and becomes available at the site of action. In practice, drug concentration-time courses are measured in the systemic circulation, and the area under the curve (AUC) as well as the observed maximum concentration (C(max)) are determined. Products are considered bioequivalent if their bioavailabilities after administration of the same molar doses are similar to such a degree that their effects, with respect to both efficacy and safety, will be essentially the same and thus, there are no relevant differences in terms of AUC and C(max). In 2002 a revised version of the 'Note for Guidance on the Investigation of Bioavailability and Bioequivalence' came into effect (CPMP/EWP/QWP/1401/98). Relevant changes in comparison to the previous version are: request for GLP-compliant bioanalytical measurements; for long half-life drugs a truncated AUC is acceptable; acceptance criteria for bioequivalence assessment and requirements for a waiver of bioequivalence studies were further specified. In this context the Biopharmaceutics Classification System (BCS) seems appropriate to decide whether in special cases of rapidly dissolving solid oral dosage forms a biowaiver may be granted or not. Products not considered critical in this matter are medicinal products for which the formulation does not affect the rate and extent of absorption, i. e. bioavailability, of the active moiety. Highly soluble (and highly permeable) drugs (BCS class I) are such candidates. Comprehensive state-of-the-art guidance on the design, conduct and analysis of bioavailability and bioequivalence studies is given in the current European guideline.

Concentrations of gonadotrophins and steroids in pre-ovulatory follicular fluid and serum in relation to stimulation protocol and outcome of assisted reproduction treatment

In this prospective, randomized study, concentrations of gonadotrophins and steroids in pre-ovulatory follicular fluid (FF) and serum were related to type of stimulation protocol as well as to the outcome of assisted reproduction in 280 women subjected to the long protocol gonadotrophin-releasing hormone (GnRH) agonist pituitary down-regulation and ovarian stimulation with either human menopausal gonadotrophin (HMG) or recombinant FSH. In the women treated with HMG, concentrations of LH, FSH, oestradiol and androstenedione in FF were significantly higher, and those of human chorionic gonadotrophin (HCG) and progesterone significantly lower, than in the women treated with recombinant FSH (rFSH). More women became pregnant and delivered in the HMG than in the rFSH group. These differences, however, were not statistically significant. Concentrations of FSH in serum and of FSH and LH in FF were significantly higher in conception than in non-conception cycles, whereas all other hormone concentrations in FF and serum were similar. The present study demonstrates that the pre-ovulatory follicular fluid hormone profile is significantly influenced by the gonadotrophin preparation used for ovarian stimulation, and suggests that ovarian stimulation with HMG results in an intra-follicular hormone profile more similar to that characterizing conception cycles than stimulation with rFSH. However, as the present data represent means of FF hormone profiles, they do not allow the conclusion of a direct correlation between the intra-follicular concentration of a certain hormone and the ability of the corresponding embryo to implant and establish an ongoing pregnancy.

Placental protein 14 concentrations in circulation related to hormonal parameters and reproductive outcome in women undergoing IVF/ICSI

Serum concentrations of placental protein 14 (PP14), steroids and gonadotrophins were related to the outcome of IVF/intracytoplasmic sperm injection in 195 normogonadotrophic women subjected to the long protocol gonadotrophin-releasing hormone agonist (GnRHa; buserelin) pituitary down-regulation protocol and gonadotrophin stimulation (HMG or rFSH). Pituitary down-regulation was initiated on cycle day 21 and the patients were randomized to either intranasal or s.c. administration of buserelin. After 14 days of down-regulation, the patients were randomized on stimulation day 1 (S1) to ovarian stimulation with 225 IU per day of either human menopausal gonadotrophin (HMG) or recombinant FSH (rFSH) for a fixed period of 7 days. The daily gonadotrophin dose was adjusted on the following day according to ovarian response. Patient's blood was sampled for PP14 and hormone analysis on cycle days 21, S1, S8 and on the day of oocyte retrieval. Mean concentrations of PP14 on day 21 of the cycle were significantly lower in conception than in non-conception cycles, whereas progesterone and oestradiol were similar in conception and non-conception cycles. PP14 concentrations on the first day of stimulation and at oocyte retrieval were significantly higher in conception than in non-conception cycles, whereas concentrations after 8 days of stimulation were similar. Neither mode of GnRHa administration nor type of gonadotrophin significantly influenced PP14 concentrations throughout ovarian stimulation. Circulating PP14 is thus an important physiological signal of the fertility status of the individual in the cycle antecedent to and during ovarian stimulation. Measuring mid-luteal serum PP14 may offer a clinical test helping to decide if infertility treatment should be initiated in the subsequent cycle.

A clinical study comparing PureSperm and SpermFilter for density gradient separation of human spermatozoa in assisted reproduction

OBJECTIVE

To compare a new density gradient medium, SpermFilter, for purifying spermatozoa in assisted reproduction with the more established medium, PureSperm.

DESIGN

Part 1, a multicenter study on 225 semen samples purified using either PureSperm (115 semen samples) or SpermFilter (110 semen samples). Part 2, a retrospective, single center study on a total of 898 assisted reproductive cycles (245 insemination cycles using husband semen, 58 insemination cycles using donor semen and 595 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles.

SETTING

Part 1, three fertility clinics in Denmark (two university-affiliated fertility clinics and one private clinic). Part 2, one university-affiliated fertility clinic in Denmark.

MAIN OUTCOME PARAMETERS

Part 1, purity of purified spermatozoa (% motile), motility index and recovery of motile spermatozoa. Part 2, malformation and baby take-home rates (insemination cycles), fertilization, cleavage, implantation, malformation and baby take-home rates (IVF/ICSI cycles).

RESULTS

No statistical differences were observed in any of the parameters investigated.

CONCLUSION

SpermFilter is a valid alternative to PureSperm in assisted reproduction technology (ART).

Human menopausal gonadotropin versus recombinant follicle-stimulating hormone in normogonadotropic women down-regulated with a gonadotropin-releasing hormone agonist who were undergoing in vitro fertilization and intracytoplasmic sperm injection: a prospective randomized study

OBJECTIVE

To evaluate clinical and endocrinological effects of intranasal (IN) vs. subcutaneous (SC) GnRH-a for pituitary down-regulation combined with hMG vs. rFSH.

DESIGN

Prospective, randomized study.

SETTING

University hospital, IVF unit.

PATIENT(S)

Three hundred seventy-nine normogonadotropic women eligible for IVF or ICSI.

INTERVENTION(S)

Randomization to intranasal (IN) or SC GnRH-a and to hMG or rFSH.

MAIN OUTCOME MEASURE(S)

Oocytes retrieved, embryos developed, clinical pregnancy, and delivery rates. Serum hormone concentrations on stimulation days 1 (S1) and 8 (S8), and oocyte pick-up (OPU) day.

RESULT(S)

After randomization, four groups were formed: IN/hMG (n = 100), IN/FSH (n = 98), SC/hMG (n = 89), and SC/FSH (n = 92). Mean number of oocytes retrieved and of transferable and transferred embryos were similar in the four groups. Clinical pregnancy rate per started cycle was significantly higher in the IN/HMG group than in the SC/FSH group (P<.05) and was intermediate in the two remaining groups. Se-LH on S8 in the two SC groups was significantly lower than in the two IN groups. Se-E2 on S8 in the SC/FSH group was significantly lower than in the other three groups.

CONCLUSION(S)

The clinical and endocrinological outcome in IVF and ICSI-treated normogonadotropic women is significantly influenced by mode of down-regulation as well as gonadotropin formulation.

Upon prolonged allergen exposure IL-4 and IL-4Ralpha knockout mice produce specific IgE leading to anaphylaxis

BACKGROUND

IL-4 and IL-13 are key regulators in atopic disorders and both signal through the receptor chain IL-4Ralpha. IL-4 and IL-13 are also the only cytokines known to induce class switching to IgE. We sought to compare allergen-specific IgE responses and allergic reactivity of wild-type (wt) mice with IL-4-/- and IL-4Ralpha-/- mice, which lack both IL-4 and IL-13 functions.

METHODS

BALB/c wt, IL-4-/- and IL-4Ralpha-/- mice were immunized with ovalbumin intranasally or intraperitoneally and specific antibody titers were measured by ELISA. Bronchoalveolar lavage fluids and lung tissue were analyzed cytologically and histologically. Allergic reactivity was determined by active cutaneous anaphylaxis and anaphylactic shock.

RESULTS

wt mice immunized intranasally or intraperitoneally showed high titers of specific IgE 3 and 6 weeks after primary sensitization, resulting in cutaneous anaphylaxis and anaphylactic shock upon challenge. Intranasal sensitization resulted in airway eosinophilia and goblet cell metaplasia. In contrast, IL-4-/- and IL-4Ralpha-/- mice showed no specific IgE after 3 weeks, but produced high titers after 6 weeks. At this time cutaneous anaphylaxis and anaphylactic shock could be induced as in wt mice, but lung pathology was absent.

CONCLUSIONS

We conclude that upon long-term allergen exposure, alternative switch mechanisms independent of IL-4 and IL-4Ralpha may induce IgE but not asthma-like lung pathology. This may be relevant for the development of allergic disease, since long-term allergen exposure is a frequent condition during allergic sensitization.

Intrauterine insemination with donor semen. An evaluation of prognostic factors based on a review of 1131 cycles

OBJECTIVE

To identify prognostic factors influencing the outcome of infertility treatment using intrauterine insemination with donor semen (IUI-D).

DESIGN

Retrospective study of all patients undergoing IUI-D between August 1st, 1990 and July 31st, 1998.

SETTING

University-affiliated infertility clinic.

PATIENTS

Three hundred and five couples undergoing 1131 IUI-D treatment cycles.

MAIN OUTCOME MEASURES

Type of hormonal treatment, number of follicles, length of follicular phase, endometrial pattern, female age, infertility diagnosis and semen quality related to clinical pregnancy rate, cumulative birth rate and multiple gestations.

RESULTS

Throughout the nine year period the overall clinical pregnancy rate per cycle was 22.3%, with an increase from 12.9% in 1990 to 34.6% in 1998. The multiple birth rate was 20.6%. The birth rate per couple was 61.1% after a mean of 3.2 treatment cycles. The pregnancy rate was highest in the first treatment cycle and the cumulative birth rate rose only slightly after the sixth treatment cycle. The following parameters were positively and significantly correlated to a successful outcome of IUI-D: i) the first treatment cycle - compared to the following up to six treatment cycles; ii) number of mature follicles - more than one - at the time of insemination, however, with an unacceptable high rate of multiple pregnancies when more than 3 mature follicles were present; iii) time of insemination after the 12th day in the cycle; iv) insemination after ovulation has occurred and; v) female age under 30 years.

CONCLUSIONS

IUI-D is a simple and inexpensive treatment giving acceptable pregnancy rates for up to six treatment cycles if at least 2 mature follicles have developed at the time of insemination, which implies that hormonal ovarian stimulation and induction of ovulation is used, and ovulation has occurred at the time of insemination, which ought to take place after cycle day (cd) 12 with at least two million motile spermatozoa.

Pharmacodynamic effects and plasma pharmacokinetics of single doses of cetrorelix acetate in healthy premenopausal women

OBJECTIVE

To investigate the pharmacodynamic effects and plasma pharmacokinetics of single subcutaneous doses of cetrorelix acetate in healthy premenopausal women.

SETTING

Phase I clinical research unit.

PATIENT(S)

Healthy, premenopausal women aged 19 to 35 years.

INTERVENTION(S)

Single subcutaneous morning doses of cetrorelix acetate (1, 3, or 5 mg peptide base) were investigated in a randomized, single-blind, placebo-controlled, parallel-group design. After a control cycle, 36 women received cetrorelix acetate (12 per dose) and 12 received placebo on the eighth individual cycle day. Transvaginal ultrasound was performed, and blood samples for LH, FSH, E2 were collected during both cycles and for pharmacokinetics up to 168 hours after dosing. The serum hormone levels were determined by electrochemicoluminescence immunoassay and plasma cetrorelix concentrations by radioimmuno assay.

RESULTS

Cetrorelix acetate administration led to a rapid, marked, and reversible suppression of serum LH, E2, and to a lesser extent FSH concentrations. The median intra-individual shifts between treatment and control cycle were -1.0, 4.0, 8.0, and 9.5 days for serum LH maximum and -1.0, 4.5, 7.0, and 10.0 days for ovulation following placebo or 1, 3, and 5 mg cetrorelix acetate, peptide base, respectively. The area under the concentration-time curve (AUC) and peak cetrorelix concentrations in plasma (Cmax) increased proportionally with dose.

CONCLUSIONS

Cetrorelix acetate showed pronounced and reversible LH and E2 suppression and a dose-dependent postponement of LH surge and ovulation after single subcutaneous administrations to healthy premenopausal women. Dose proportionality over the range of 1 mg to 5 mg cetrorelix acetate, peptide base was demonstrated.

Homologous intrauterine insemination. An evaluation of prognostic factors based on a review of 2473 cycles

OBJECTIVE

To identify prognostic factors influencing the outcome of infertility treatment using homologous intrauterine inseminations (IUI-H).

DESIGN

Retrospective study of all patients undergoing IUI-H at the Fertility Clinic, Odense University Hospital from August 1st, 1990 to July 31st, 1998.

SETTING

University-affiliated infertility clinic.

PATIENTS

Eight hundred and ninety-three couples undergoing 2473 IUI-H treatment cycles.

MAIN OUTCOME MEASURES

Infertility diagnosis, female age, number of follicles, type of hormonal treatment, length of follicular phase, endometrial pattern, and semen quality related to clinical pregnancy rate, cumulative birth rate and multiple gestations.

RESULTS

Throughout the nine year period the overall clinical pregnancy rate per IUI-H cycle was 11.9% with a significant increase from 8.7% in 1990 to 14.8% in 1998. The multiple birth rate was 18.1%. The birth rate per couple was 27.2% after a mean of 2.8 treatment cycles. The pregnancy rate was highest in the first treatment cycle and the cumulative birth rate rose only slightly after the fourth treatment cycle. Of the main outcome measures the following were positively and significantly related to a successful outcome of IUI: i) The first treatment cycle - compared to the following up to six treatment cycles; ii) number of mature follicles up to five - at the time of insemination, however, with an unacceptable high rate of multiple pregnancies with more than 4 mature follicles; iii) use of CC/hMG-FSH as compared to CC only for ovarian stimulation; iv) number of motile sperms inseminated exceeding 5 million; v) time of insemination between the 13th and the 16th day in the cycle and vi) anovulatory or idiopathic infertility.

CONCLUSIONS

IUI-H is a simple and inexpensive treatment giving acceptable pregnancy rates for up to four treatment cycles providing that at least 3 to 4 mature follicles have developed at the time of insemination, which implies that hormonal ovarian stimulation and induction of ovulation is used, that insemination occurs between cycle day 13 and 16 and that at least 5 million motile sperms are available for insemination. Our results indicate that in the presence of tubal pathology or less than 5 million motile sperms, the couples should be referred directly to IVF-treatment.

Pharmacokinetic and pharmacodynamic modeling of cetrorelix, an LH-RH antagonist, after subcutaneous administration in healthy premenopausal women

PURPOSE

The purpose of this study was the development of pharmacokinetic and pharmacodynamic models for the luteinizing hormone (LH) suppression and subsequent shift in LH surge and follicle-stimulating hormone by cetrorelix in women.

BACKGROUND

Cetrorelix is a potent luteinizing hormone-releasing hormone (LH-RH) antagonist and is used for the prevention of the premature ovulation indicated by an LH surge in in vitro fertilization. The pharmacokinetic and pharmacodynamic relationship for the suppression and the shift in the LH surge has not yet been established.

METHODS

In a placebo-controlled study, single subcutaneous doses of 1, 3, and 5 mg of cetrorelix were given to 36 subjects on day 8 of the natural menstrual cycle. Cetrorelix, LH, follicle-stimulating hormone, estradiol, and progesterone were determined.

RESULTS

Cetrorelix pharmacokinetics were described by a 2-compartment model with a terminal half-life of 56.9 +/- 27.1 hours. Mean shift in LH surge was by 4.1, 7.5, and 9.3 days with the 1-, 3-, and 5-mg doses, respectively. An indirect response sigmoid Emax model was developed for the suppression of LH and the shift in the LH surge. The inhibitory concentration of 50% (for LH suppression) and median effective concentration (for surge shift) estimates were 3.6 ng/mL and 1.6 ng/mL, respectively. The suppression of follicle-stimulating hormone was described by a similar Emax model, with an inhibitory concentration of 50% of 7.25 ng/mL.

CONCLUSIONS

A pharmacokinetic and pharmacodynamic model was developed for the transient initial suppression of LH and the subsequent shift in the LH surge after 3 single subcutaneous doses of cetrorelix without ovarian stimulation. A separate model was developed for the suppression of follicle-stimulating hormone by cetrorelix. The shift in the LH surge could be adequately described by the model.

The influence of infections on the development and severity of allergic disorders

The frequency and severity of atopic disorders are steadily increasing, particularly in developing countries. The reason for this observation is not clear. Recent studies indicate that infections with viruses and especially with bacteria early in life may help to inhibit allergic Th2 responses by skewing the immune system towards Th1 responses. However, infections can also lead to the exacerbation of atopic disorders.

Molecular diagnosis of a familial nonhemolytic hyperbilirubinemia (Gilbert's syndrome) in healthy subjects

Recent research has shown that congenital nonhemolytic low grade hyperbilirubinemias in patients with Gilbert's syndrome (GS) are linked to mutations in the TATA box upstream of the uridine 5'-diphosphoglucose glucuronosyltransferase (UGT1A1) gene leading to an impaired bilirubin glucuronidation. In routine clinical practice GS patients can, however, only be suspected by exclusion of other causes of hyperbilirubinemia or substantial liver diseases. We developed a new, sensitive, convenient, and economic polymerase chain reaction (PCR) method for the rapid and reliable identification of gene polymorphisms in the TATA box of the UGT1A1 gene using fluorescence resonance energy transfer (FRET). With this procedure the genotype frequency in a cohort of 266 unrelated individuals from Southern Germany was investigated and the allelic distribution for individual genotypes was 43:45:12 for the (TA)(6)TAA:(TA)(6)TAA/(TA)(7)TAA:(TA)(7)TAA alleles, respectively. The homozygous (TA)(7)TAA genotype was strongly associated with suspected Gilbert's patients and its prevalence in our cohort of 266 Southern German individuals was 12.4%. In this cohort total mean serum bilirubin levels ranged from 5 micromol/L (wild-type 6/6 allele) to 57 micromol/L serum total bilirubin (mutant 7/7 homozygous allele). Median (interquartile range) serum total bilirubin levels were 12 (6) and 21 (13) for the homozygous wild-type and mutant allele, respectively. Our assay enables individual guidance for dose adjustment in suspected GS patients undergoing long-term drug therapies, especially if glucuronidation via UGT1A1 is a major metabolic pathway.

Selective suppression of inhibitory synaptic transmission by nocistatin in the rat spinal cord dorsal horn

Nociceptin/orphanin FQ (N/OFQ) and nocistatin (NST) are two recently identified neuropeptides with opposing effects on several CNS functions, including spinal nociception. The cellular mechanisms that underlie this antagonism are not known. Here, we have investigated the effects of both peptides on synaptic transmission mediated by the three fast neurotransmitters l-glutamate, glycine, and GABA in the superficial layers of the rat spinal cord horn, which constitute the first important site of integration of nociceptive information in the pain pathway. NST selectively reduced transmitter release from inhibitory interneurons via a presynaptic Bordetella pertussis toxin-sensitive mechanism but left excitatory glutamatergic transmission unaffected. In contrast, N/OFQ only inhibited excitatory transmission. In the rat formalin test, an animal model of tonic pain in which N/OFQ exerts antinociceptive activity, NST induced profound hyperalgesia after intrathecal application. Similar to glycine and GABA(A) receptor antagonists, NST had no significant effects in the rat tail-flick test, a model of acute thermal pain. Our results provide a cellular basis for the antagonism of N/OFQ and NST and suggest the existence of a so far unidentified membrane receptor for NST. In addition, they support a role of NST as an endogenous inhibitor of glycinergic and GABAergic neurotransmission in the sensory part of the spinal cord and as a mediator of spinal hyperalgesia.

Pituitary and gonadal endocrine effects and pharmacokinetics of the novel luteinizing hormone-releasing hormone antagonist teverelix in healthy men--a first-dose-in-humans study

BACKGROUND. Teverelix is a novel synthetic peptidic luteinizing hormone-releasing hormone (LHRH) antagonist.

METHODS

Single subcutaneous morning doses of teverelix acetate (either 0.5, 1, 2, 3, or 5 mg base) were investigated in a randomized, single-blind, placebo-controlled, dose-escalating parallel-group design in healthy men. Six subjects received teverelix, and two subjects received placebo per dose level. Blood samples for lutropin, luteinizing hormone (LH), and follitropin, follicle-stimulating hormone (FSH), and testosterone, as well as for pharmacokinetics, were withdrawn up to 120 hours after dosing. Serum hormone levels were determined by electrochemicoluminescence immunoassays, and plasma teverelix concentrations were determined by radioimmunoassay.

RESULTS

Teverelix led to a rapid, marked suppression of LH, testosterone and, to a lesser extent, FSH. Median maximum suppressions compared with predose levels were -93% for LH and -54% for FSH after teverelix 5 mg, and -93% for testosterone after teverelix 3 mg, respectively. After 5 mg teverelix, testosterone suppression <1 ng/mL started a median of 12 hours after dosing and lasted for a median of 33 hours. The duration of testosterone suppression increased with dose. Geometric means of peak teverilix plasma concentrations were 4.5 ng/mL (0.5 mg teverelix) to 49.0 ng/mL (5 mg teverelix) and tmax occurred between 1 and 4 hours after dosing. Geometric means of the area under the teverelix plasma concentration-time course from zero to time of the last quantifiable plasma concentration [AUC(O-tlast)] were 54.9 ng x h/mL (0.5 mg teverelix) to 881.8 ng x h/mL (5 mg teverelix). Median values for apparent terminal half-lives ranged from 24 to 75 hours. The most frequently reported adverse events were short-lasting mild injection-site reactions.

CONCLUSIONS

Teverelix showed pronounced LH and testosterone suppressive effects after single subcutaneous doses in healthy men. Duration of hormone suppression increased with dose. Teverelix was well tolerated. This profile indicates potential for further clinical use.