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1.
Qual Life Res ; 32(8): 2223-2234, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36928650

ABSTRACT

PURPOSE: Psychosocial health (PH) and quality of life (QoL) are important health outcomes. We compared PH and QoL of adolescents conceived with intrazytoplasmatic sperm injection (ICSI) and of naturally conceived controls. The impact of disclosure of ICSI-conception on QoL and PH was quantified. METHODS: The cross-sectional sample consisted of 545 ICSI-conceived adolescents and 427 unmatched singleton controls aged 14-18 years. Adolescents reported PH with the 'Strengths and Difficulties Questionnaire' (low values indicating high PH), and QoL with the KINDL questionnaire (high values indicating high QoL). Because of clustering of multiples within families, adjusted linear regressions with generalized estimating equations were used to compare ICSI- and naturally conceived adolescents. Missing values were treated by multiple imputation. Minimal importance was defined as half a standard deviation. RESULTS: Both ICSI and control adolescents had high PH (low mean 'total difficulties' score: 9 of 40) and high QoL (mean 'total KINDL' score: 75 of 100). Differences were generally in favour of the ICSI group. Significant differences occurred for 'impact of behavioural problems' (p = 0.033), the 'total KINDL' score (p = 0.021) and the dimensions 'physical wellbeing' (p = 0.031) and 'school' (p = 0.005), but all differences were far below minimal importance. About 80% of ICSI adolescents were informed about their mode of conception. PH and QoL were slightly higher in informed adolescents; behavioural difficulties ('total behavioural problems' and 'conduct problems') were significantly lower (p = 0.013 and p = 0.003), behavioural strengths ('prosocial behaviour') and 'physical QoL' significantly higher (p = 0.004 and p = 0.018), but differences remained clearly below minimal importance. CONCLUSIONS: Our results are reassuring for parents using ICSI and their children. Speaking openly about an ICSI conception in the family may be beneficial.


Subject(s)
Quality of Life , Sperm Injections, Intracytoplasmic , Child , Humans , Male , Adolescent , Quality of Life/psychology , Cross-Sectional Studies , Semen , Fertilization
2.
Hum Reprod ; 35(4): 968-976, 2020 04 28.
Article in English | MEDLINE | ID: mdl-32240284

ABSTRACT

STUDY QUESTION: Are there any differences in the pubertal development and reproductive hormone status during adolescence between singletons following ICSI therapy or spontaneous conception (SC)? SUMMARY ANSWER: Pubertal development and reproductive hormone levels are largely similar between ICSI and SC adolescents, except for a tendency towards lower inhibin B levels as well as significantly higher estradiol levels and a lower testosterone-to-estradiol-ratio in male adolescents. WHAT IS KNOWN ALREADY: Previous data are scarce and partly inconclusive regarding pubertal development in female ICSI adolescents as well as demonstrating a tendency towards lower inhibin B serum levels in male ICSI offspring. STUDY DESIGN, SIZE, DURATION: Prospective controlled study including 274 singleton ICSI-conceived adolescents (141 girls, 133 boys) followed up for the third time, and 273 SC controls (142 girls, 131 boys) from seven German registration offices (Aachen, Eichstätt, Erfurt, Lübeck, Hamburg, Heidelberg and Schwerin). PARTICIPANTS/MATERIALS, SETTING, METHODS: Pubertal development assessed by Tanner staging (breast, genital and pubic hair development), age at menarche and reproductive hormone levels were analyzed in ICSI and SC adolescents at the mean age of 16.5 years. Differences were analyzed by multinomial regression (Tanner stages) or t test and linear regression for hormonal assessments. MAIN RESULTS AND THE ROLE OF CHANCE: Both female and male ICSI and SC adolescents showed adequate pubertal maturation according to their age, and the mean age at menarche (at 12.7 versus 12.8 years) was similar. Tanner stages as well did not display any relevant or significant differences between the groups. Reproductive hormone levels in female adolescents not using hormonal contraception were largely similar before and after adjustment for several factors such as preterm birth, Tanner stages, BMI or physical activity. In male ICSI adolescents, a tendency towards lower inhibin B (-14.8 pg/ml, 95% CI: -34.2 to 4.6 pg/ml), significantly higher estradiol (2.6 ng/l, 95% CI: 0.0 to 5.2 ng/l) and a significantly lower testosterone-to estradiol ratio (-0.047, 95% CI: -0.089 to -0.004) was found. LIMITATIONS, REASONS FOR CAUTION: The all-over response rate and the willingness to participate in the blood test and medical examination were very low in the control group. Participating control families may have greater health awareness, and selection bias cannot be ruled out. Hormonal data in the females were measured irrespective of the cycle day and restricted to those not using hormonal contraception. Some parameters from the questionnaire data such as usage of hormonal contraception might suffer from reporting bias. As this is an observational study, we can draw only limited causal conclusions from the findings. WIDER IMPLICATIONS OF THE FINDINGS: Differences in male reproductive hormones may indicate altered testicular function. However, at this time possible consequences for later reproductive success are unknown. STUDY FUNDING/COMPETING INTEREST(S): DFG research grant KA 1643/4-1. The authors declare no conflict of interest.


Subject(s)
Premature Birth , Sperm Injections, Intracytoplasmic , Adolescent , Female , Humans , Infant, Newborn , Male , Menarche , Pregnancy , Prospective Studies , Testosterone
3.
Reprod Biomed Online ; 25(2): 190-2, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22683152

ABSTRACT

In women, anti-Müllerian hormone (AMH) is exclusively expressed in granulosa cells and an established marker of ovarian reserve. In menstrual cycle disorders, low AMH is usually interpreted as an indicator of primary ovarian insufficiency. This study is a case series of 11 patients with hypopituitarism. AMH concentrations were on or below the age-specific 25th percentile in three of the four patients diagnosed in infancy, but not in the remaining seven patients, who were diagnosed during adolescence or later. In patients with hypopituitarism, the detection of low AMH serum concentrations can present a diagnostic pitfall and its value in the interpretation of ovarian reserve in these patients is challenging.


Subject(s)
Anti-Mullerian Hormone/blood , Hypopituitarism/blood , Hypopituitarism/diagnosis , Ovary/physiology , Adolescent , Age Factors , Biomarkers/blood , Child , Female , Humans , Infant , Ovary/diagnostic imaging , Ultrasonography , Uterus/diagnostic imaging
4.
Exp Clin Endocrinol Diabetes ; 120(2): 73-9, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22068615

ABSTRACT

BACKGROUND: Polycystic ovary syndrome (PCOS) is a frequent heterogenic disorder with a familial background. Androgenic effects, determining the clinical features of the syndrome, are mediated by the androgen receptor (AR), whose activity is modulated by a genetic polymorphism. We investigated the role of the CAG repeat polymorphism of the androgen receptor in PCOS. METHODS: In the infertility unit of a university clinic, 72 PCOS patients were compared with 179 ovulatory controls undergoing a standardized diagnostic work-up. The number of CAG repeats was determined by PCR, labelling with IR-800 and PAGE. X-chromosome inactivation was assessed by a methylation-sensitive assay. RESULTS: Compared to controls, PCOS patients displayed a shorter mean CAG repeat length, encoding for higher AR activity (P=0.001). CAG repeat length correlated inversely with oligomenorrhea, a central androgen dependent feature of the syndrome (P=0.005). In a binomial regression analysis including BMI, LH and free testosterone, CAG repeat length was identified as an independent risk factor for PCOS (P=0.002). CONCLUSIONS: The CAG repeat polymorphism could constitute one of the genetic factors modulating the syndrome's phenotype, contributing to its clinical heterogeneity and associated metabolic consequences.


Subject(s)
Polycystic Ovary Syndrome/genetics , Receptors, Androgen/genetics , Trinucleotide Repeat Expansion/genetics , Adult , Base Sequence , Case-Control Studies , Female , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Menstrual Cycle/genetics , Menstrual Cycle/physiology , Phenotype , Polycystic Ovary Syndrome/etiology , Polycystic Ovary Syndrome/metabolism , Polymorphism, Genetic/physiology , Receptors, Androgen/physiology , Risk Factors , X Chromosome Inactivation/physiology , Young Adult
5.
Reproduction ; 141(4): 481-90, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21292727

ABSTRACT

Improvements in cancer survival rates have renewed interest in the cryopreservation of ovarian tissue for fertility preservation. We used the marmoset as a non-human primate model to assess the effect of different cryoprotectives on follicular viability of prepubertal compared to adult ovarian tissue following xenografting. Cryopreservation was performed with dimethylsulfoxide (DMSO), 1,2-propanediol (PrOH), or ethylene glycol (EG) using a slow freezing protocol. Subsequently, nude mice received eight grafts per animal from the DMSO and the PrOH groups for a 4-week grafting period. Fresh, cryopreserved-thawed, and xenografted tissues were serially sectioned and evaluated for the number and morphology of follicles. In adult tissue, the percentage of morphologically normal primordial follicles significantly decreased from 41.2 ± 4.5% (fresh) to 13.6 ± 1.8 (DMSO), 9.5 ± 1.7 (PrOH), or 6.8 ± 1.0 (EG) following cryopreservation. After xenografting, the percentage of morphologically normal primordial (26.2 ± 2.5%) and primary follicles (28.1 ± 5.4%) in the DMSO group was significantly higher than that in the PrOH group (12.2 ± 3 and 5.4 ± 2.1% respectively). Proliferating cell nuclear antigen (PCNA) staining suggests the resumption of proliferative activity in all cellular compartments. In prepubertal tissues, primordial but not primary follicles display a similar sensitivity to cryopreservation, and no significant differences between DMSO and PrOH following xenografting were observed. In conclusion, DMSO shows a superior protective effect on follicular morphology compared with PrOH and EG in cryopreserved tissues. Xenografting has confirmed better efficacy of DMSO versus PrOH in adult but not in prepubertal tissues, probably owing to a greater capacity of younger animals to compensate for cryoinjury.


Subject(s)
Cryopreservation , Cryoprotective Agents/adverse effects , Graft Survival/drug effects , Ovarian Follicle/physiology , Ovarian Follicle/transplantation , Ovary , Sexual Maturation/physiology , Animals , Choice Behavior , Cryoprotective Agents/pharmacology , Dimethyl Sulfoxide/adverse effects , Dimethyl Sulfoxide/pharmacology , Drug Resistance/physiology , Ethylene Glycol/adverse effects , Ethylene Glycol/pharmacology , Female , Graft Survival/physiology , Ovarian Follicle/drug effects , Primates , Propylene Glycol/adverse effects , Propylene Glycol/pharmacology , Transplantation, Heterologous
6.
Phys Rev Lett ; 103(13): 137401, 2009 Sep 25.
Article in English | MEDLINE | ID: mdl-19905539

ABSTRACT

Symmetrical fluorescence yield profiles and asymmetrical electron yield profiles of the preresonances at the La N_{IV,V} x-ray absorption edge are experimentally observed in LaPO_{4} nanoparticles. Theoretical studies show that they are caused by interference effects. The spin-orbit interaction and the giant resonance produce symmetry entangled intermediate states that activate coherent scattering and alter the spectral distribution of the oscillator strength. The scattering amplitudes of the electron and fluorescence decays are further modified by the spin-orbit coupling in the final 5p;{5}epsilonl and 5p;{5}4f;{1} states.

7.
Ann Endocrinol (Paris) ; 68(2-3): 160-6, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17544358

ABSTRACT

Follicle-stimulating hormone (FSH) is a key factor in human reproduction. FSH activates its receptor (FSHR) located exclusively on Sertoli cells in the testis and granulosa cells in the ovary. Two common single nucleotide polymorphisms (SNP) within exon 10 of the human FSHR gene result in two almost equally common allelic variants exhibiting threonine (Thr) or alanine (Ala) at position 307 in the hinge region, respectively, asparagine (Asn) or serine (Ser) at codon 680 of the intracellular domain. Clinical studies have demonstrated that p.N680S polymorphism determines the ovarian response to FSH stimulation in patients undergoing IVF-treatment. Patients with the Ser(680) allele need more FSH during the stimulation phase to reach the serum estradiol levels of Asn(680) patients. A study investigating women with normal, mono-ovulatory menstrual cycles revealed that the Ser(680)/Ser(680) genotype leads to higher FSH serum levels and a prolonged cycle. To date, the molecular mechanism underlying the partial "resistance" of the Ser(680)-FSHR to FSH remains unclear. Future experiments should extend our current understanding of FSH action on follicular selection and dominance, thereby permitting novel, patient-tailored therapies for infertility and fertility preservation.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Ovary/drug effects , Receptors, FSH/genetics , Alleles , Female , Humans , Polymorphism, Genetic/genetics , Polymorphism, Single Nucleotide , Receptors, FSH/drug effects
9.
J Clin Endocrinol Metab ; 90(8): 4866-72, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15886248

ABSTRACT

CONTEXT: FSH is essential for follicular maturation. Data from ovarian hyperstimulation cycles suggest that FSH action is attenuated by a frequent single nucleotide polymorphism of the FSH receptor gene exchanging Asn for Ser at codon 680. OBJECTIVE: We hypothesized that the FSH receptor genotype influences menstrual cycle dynamics. DESIGN: Menstrual cycle was monitored from the midluteal phase through ovulation until the consecutive menstruation. SETTING: The study was conducted at the University research center. SUBJECTS: Women homozygous for the Asn680 (n = 12) and Ser680 (n = 9) variants with normal menstrual cycles volunteered for the study. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASUREMENTS: Follicular growth, serum LH, FSH, estradiol, progesterone, inhibin A, inhibin B and antimullerian hormone were measured. RESULTS: During the luteo-follicular transition, serum levels of estradiol, progesterone, and inhibin A were significantly lower, and FSH started to rise earlier in the Ser680/Ser680 group. FSH levels were steadily and significantly higher, and the mean area under the FSH curve was 31% greater in this group (P < 0.002). No differences were observed in estradiol, inhibin B, and growth velocities of dominant follicles. The time from luteolysis to ovulation was significantly longer in women with the Ser680/Ser680 (13.6 +/- 1.01 d) compared with Asn680/Asn680 (11.3 +/- 0.61 d, P < 0.05) genotype with a significant difference in total menstrual cycle length (29.3 vs. 27.0 d, respectively; P < 0.05). CONCLUSIONS: The FSH receptor Ser680/Ser680 genotype is associated with higher ovarian threshold to FSH, decreased negative feedback of luteal secretion to the pituitary during the intercycle transition, and longer menstrual cycles.


Subject(s)
Menstrual Cycle/genetics , Polymorphism, Single Nucleotide , Receptors, FSH/genetics , Adolescent , Adult , Exons/genetics , Feedback, Physiological/genetics , Female , Genotype , Humans , Menstrual Cycle/physiology
10.
Reprod Biomed Online ; 9(3): 271-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15353074

ABSTRACT

The hypothesis was tested that conception cycles (CC) resulting from IVF can be distinguished from non-conception cycles (NC) by differences in corpora lutea function that are detectable at the earliest stage of embryo implantation. Luteal oestradiol secretion was analysed retrospectively in 409 ovarian stimulation cycles of 296 patients from the day of embryo transfer until 14 days after embryo transfer (ET+14) in IVF/intracytoplasmic sperm injection (ICSI) cycles. Human chorionic gonadotrophin (HCG) was administered in 330 of 409 cycles in addition to vaginal progesterone in all cycles. Differences in serum oestradiol concentrations between CC and NC increased from day ET+1 onward and became statistically significant on days ET+4 through ET+14, with higher oestradiol concentrations in CC compared with NC. Even though exogenous HCG administration prevented the fall in luteal oestradiol concentrations after ET+4 both in CC and NC, increasing differences in oestradiol concentrations between CC and NC after embryo transfer were observed in both groups of HCG-supplemented and non-supplemented cycles. It is concluded that luteal oestradiol secretion is affected at the earliest stage of embryo implantation. The putative early signal to the corpus luteum associated with embryo attachment and early implantation appears to be superimposed onto the effect of exogenous luteal HCG administration and is clearly distinguishable as early as 4 days after embryo transfer in conception cycles.


Subject(s)
Corpus Luteum/metabolism , Embryo Implantation/physiology , Embryo Transfer , Estradiol/metabolism , Fertilization in Vitro , Chorionic Gonadotropin/administration & dosage , Estradiol/blood , Female , Humans , Luteal Phase , Pregnancy , Progesterone/administration & dosage , Sperm Injections, Intracytoplasmic , Time Factors
11.
Br J Cancer ; 91(3): 434-40, 2004 Aug 02.
Article in English | MEDLINE | ID: mdl-15226779

ABSTRACT

Endothelin-1 (ET-1) and its receptors (ETAR and ETBR), referred to as the endothelin (ET) axis, are overexpressed in breast carcinomas and appear to influence tumour growth and progression. The objective of this study was to determine the effect of expression of the ET axis in breast carcinomas on response to cytotoxic chemotherapy. The study included 44 patients with locally advanced breast cancer participating in a prospective phase III study evaluating high-dose neoadjuvant chemotherapy of epirubicin and cyclophosphamide. Expression of ET-1, ETAR and ETBR was determined by semiquantitative immunohistochemical analysis of breast cancer tissue from prechemotherapy tru-cut biopsies. Immunohistochemical staining was positive for ET-1 in 61.5%, for ETAR in 35% and for ETBR in 35.9% of breast carcinomas. Pathological response to chemotherapy was significantly decreased in ETAR-positive patients (P=0.002). In total, 50% of ETAR-positive patients as compared to 7.7% of ETAR-negative patients attained pathologically 'no change'. Logistic regression confirmed ETAR as an independent predictive marker for pathological response (P=0.009). These data indicate that increased expression of ETAR in breast carcinomas is associated with resistance to chemotherapy. Determination of ETAR status may serve as a predictive marker for identifying patients less likely to be responsive to conventional chemotherapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Carcinoma/drug therapy , Carcinoma/genetics , Gene Expression Profiling , Receptor, Endothelin A/biosynthesis , Adult , Aged , Chemotherapy, Adjuvant , Cyclophosphamide/administration & dosage , Drug Resistance, Neoplasm , Endothelin-1/analysis , Endothelin-1/biosynthesis , Epirubicin/administration & dosage , Female , Humans , Immunohistochemistry , Middle Aged , Neoadjuvant Therapy , Predictive Value of Tests , Receptor, Endothelin A/analysis , Receptor, Endothelin B/analysis , Receptor, Endothelin B/biosynthesis , Sensitivity and Specificity , Treatment Outcome
12.
Schmerz ; 17(2): 131-6, 2003 Apr.
Article in German | MEDLINE | ID: mdl-12695894

ABSTRACT

OBJECTIVE: The improvement of ambulant treatment for patients with chronic headache or cancer pain. METHODS: Distribution of accepted guidelines and standards by means of the internet in order to make this knowledge known among general practitioners and to give patients better access to this information. RESULTS: We have built an internet manual about the treatment of chronic headache and cancer pain. About 9100 readers accessed the manual during a period of 33 months. The manual has been completely downloaded 279 times. Physicians and patients very often used search engines to access the manual in their search for information about headache. The terms "migraine" and "tension type headache" were looked up the most. CONCLUSIONS: It is worthwhile editing medical information for use on the internet and thus making it available to the public.


Subject(s)
Headache/therapy , Internet , Online Systems , Pain Management , Ambulatory Care Facilities/organization & administration , Chronic Disease , Family Practice , Germany , Humans , Manuals as Topic , Neoplasms/physiopathology
13.
Schmerz ; 16(4): 294-303, 2002 Aug.
Article in German | MEDLINE | ID: mdl-12192438

ABSTRACT

Chronic pain is the most frequent symptom leading to medical expertise in general medicine, orthopedics, neurology and psychiatry. Because of the importance of psychosocial factors in the onset and the course of chronic pain syndromes a basic psychosomatic diagnostic in every medical expertise of chronic pain is necessary. In case of hints to relevant psychosocial factors in the onset and the process of chronicity of the pain syndrome a psychotherapeutic medical expertise for the assessment of the form and the severity of the psychic disorder and psychosocial conflicts as causes, consequences or comorbidities of the pain and its social consequences is mandatory. Within a structured procedure using international diagnostic systems and classifications of severity scores and disabilities an reproducible assessment of performance is possible. The guidelines of the German psychosomatic and psychotherapeutic scientific societies for medical expertising are presented with their relevance to the assessement of patients with chronic pain syndromes. Furthermore the authors discuss based on their own experiences and the literature some controversial issues between medical experts and officials in charge of pension insurance companies.


Subject(s)
Pain/psychology , Psychotherapy , Chronic Disease , Disabled Persons/psychology , Humans , Mental Disorders/physiopathology , Mental Disorders/psychology , Severity of Illness Index , Syndrome
14.
Schmerz ; 16(1): 41-7, 2002 Feb.
Article in German | MEDLINE | ID: mdl-11845340

ABSTRACT

In a regional pain management network in Cologne, sponsored by the German Ministry of Health, structures of outpatient pain treatment in general practice and the adherence to pain management guidelines were examined. The 3-year project was divided into a 1-year observational period to analyze the present state of outpatient pain management followed by a 2-year period of interventions such as consultations and educational training programs in pain treatment. Eighty physicians with different specializations working in general practice took part in the network. The knowledge of and adherence to the guidelines for the treatment of headache and cancer pain were examined by questionnaire surveys and six simulated patient cases. These investigations were performed yearly from 1997 to 2000. The adherence to the guidelines for the treatment of headache and cancer pain by the physicians participating in the network was low. The levels achieved for simulated cases of headache were higher than for cancer pain. The results of simulated patient cases from the beginning and the end of the project were available for comparison for 28 physicians. Evaluation of the physicians' assessment of the simulated patient cases increased only fractionally and was not significant in headache patients (median change of 0.67) and cancer pain patients (median change of 0.17). The network interventions resulted in a slight improvement in the knowledge of and attitudes to the treatment of headache and cancer pain as judged by simulated patient cases. This improvement, however, did not reach statistical significance. The small number of physicians answering at the beginning and at the end of the project made it difficult to draw a general conclusion on whether the interventions had led to an improvement in outpatient pain management in a larger group of physicians.


Subject(s)
Headache/therapy , Neoplasms/physiopathology , Pain Management , Practice Guidelines as Topic , Adult , Female , Humans , Male , Middle Aged , Outpatients , Pain/etiology , Quality of Health Care
15.
Hum Reprod ; 16(8): 1648-52, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11473957

ABSTRACT

BACKGROUND: There is an increased rate of chromosomal anomalies, in particular low-level sex chromosome mosaicism, in the female partners of couples undergoing intracytoplasmic sperm injection (ICSI). METHODS: Among 811 consecutive couples presenting for pre-ICSI chromosome analysis, chromosomal abnormalities were detected in 54 individuals, of which 26 were low-level sex chromosome mosaicism in the females. Attention was focused on the treatment course and outcome of ICSI in 20 couples with low-level sex chromosome mosaicism in the females actually embarking on ICSI treatment (group I, n = 38 ICSI treatment cycles). Applying a case-control design, each of the 20 couples was matched according to female age and source of spermatozoa to couples without a chromosomal abnormality in either of the partners (group II, n = 38 ICSI treatment cycles). RESULTS: No significant differences were found between the groups in ovarian response, fertilization rate and number of embryos transferred. Pregnancy rates, as well as implantation and abortion rates did not differ significantly between the groups. CONCLUSIONS: The data suggest that low-level sex chromosome mosaicism in females has no major effect on the course and outcome of ICSI.


Subject(s)
Mosaicism , Sex Chromosome Aberrations , Sperm Injections, Intracytoplasmic , Treatment Outcome , Abortion, Spontaneous , Embryo Implantation , Embryo Transfer , Estradiol/blood , Female , Humans , Infertility/genetics , Karyotyping , Male , Ovulation Induction , Pregnancy , Pregnancy Outcome
16.
Microb Ecol ; 42(3): 217-227, 2001 Oct.
Article in English | MEDLINE | ID: mdl-12024247

ABSTRACT

Three aspects of size selective feeding by the scuticociliate Cyclidium glaucoma were studied in continuous cultivation systems. Firstly, grazing-induced changes in abundance, biomass, and size structure of a bacterial community were investigated. Secondly, we studied possible grazing-protection mechanisms of bacteria as a response to permanent presence of the predator. And finally, we were looking for potential feedback mechanisms within this predator-prey relationship, i.e., how the ciliate population reacted to a changed, more grazing-protected bacterial community. The first stage of the cultivation system consisted of the alga Cryptomonas sp. and the accompanying mixed bacterial community. These organisms were transferred to two second stage vessels, a control stage without ciliates and a second one inoculated with C. glaucoma. After the first week, the abundance of bacteria in the latter decreased by 60% and remained stable until the end of the experiment (65 d), whereas bacterial biomass was less affected (393 mg C L-1 during days 0-7, 281 mg C L-1 afterwards). The mean bacterial cell volume doubled from 0.089 mm3 to 0.167 mm3, which was mainly due to increasing cell widths. During the whole investigation period formation of colonies or filaments was not observed, but we found a clear feedback of ciliates on bacterial size. An increase in bacterial cell volume was always followed by a decline of the predator population, resulting in a yet undescribed type of microbial predator-prey relation. Literature and our own data on the optimal food size range grazed by C. glaucoma showed that bacterial cell width rather than length was responsible for that observed phenomenon. Finally, we suggest that uptake rates of spherical latex beads give only limited information on truly ingestible prey volumes and that prey geometry should be considered in future studies on size selective feeding of protists.

17.
Hum Reprod ; 15(12): 2478-82, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11098014

ABSTRACT

The timing of sexual intercourse in relation to ovulation strongly influences the chance of conception. Daily serum LH measurements or transvaginal ultrasonography are not practical to determine ovulation in consecutive cycles for an individual. A prospective study was initiated to test the home use performance of the ClearPlan Fertility Monitor (CPFM) in ovulation prediction compared with transvaginal ultrasonography and serum hormone measurements. A total of 53 women aged 18-39 years with a normal uterus and at least one ovary, cycle length between 21-42 days and not using medication which interferes with ovarian function contributed 150 cycles for analysis. One cycle was anovulatory and no LH surge, indicating peak fertility, was detected by the monitor. Of the remaining 149 cycles, 135 (90.6%) had a monitor LH surge and ultrasonographically confirmed ovulation. Ovulation was detected in 91.1% of cycles during the 2 days of CPFM peak fertility. Ovulation was observed in 51.1% of cycles 1 day and in 43.2% of cycles 2 days after the surge in serum LH. Ovulation never occurred before CPFM peak fertility or the serum LH surge day. CPFM can help women who desire pregnancy to time intercourse. It may also have potential as a diagnostic aid and for monitoring the treatment of infertility.


Subject(s)
Estrone/analogs & derivatives , Estrone/urine , Luteinizing Hormone/urine , Ovarian Follicle/diagnostic imaging , Ovulation Detection/methods , Adolescent , Adult , Estradiol/blood , Female , Fertility , Humans , Luteinizing Hormone/blood , Menstrual Cycle , Ovulation Detection/instrumentation , Prospective Studies , Reagent Strips , Ultrasonography
18.
Phys Rev Lett ; 85(18): 3825-9, 2000 Oct 30.
Article in English | MEDLINE | ID: mdl-11041937

ABSTRACT

We present the first observation of self-amplified spontaneous emission (SASE) in a free-electron laser (FEL) in the vacuum ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approximately 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width, and intensity fluctuations, are all consistent with the present models for SASE FELs.

19.
Z Arztl Fortbild Qualitatssich ; 94(6): 495-500, 2000 Aug.
Article in German | MEDLINE | ID: mdl-10996940

ABSTRACT

In a regional pain management network in Cologne, the pain clinic of the department of anaesthesiology and the departments of psychosomatic medicine and of informatics, statistics and epidemiology have been cooperating with the regional board of physicians and more than 80 general practitioners since 1996. The program is sponsored by the German Ministry of Health. In this network, guidelines for the management of chronic pain have been implemented for outpatient care in the last three years. Results from the first year confirm the high level of distress of patients with chronic pain. Consultation and education offered by the coordinating office and in training courses were accepted by the practitioners in variable degrees. Some physicians requested consultations frequently while including only a few patients in the study documentation, while other physicians requested consultations rarely and assessed many patients. Participating physicians were also asked to provide analgesic regimens for constructed case reports with chronic headache or cancer pain. The evaluation of these prescriptions showed poor adherence to analgesic guidelines.


Subject(s)
Pain Management , Ambulatory Care/standards , Chronic Disease , Germany , Guidelines as Topic , Humans , Patient Care Team , Quality Assurance, Health Care
20.
Z Arztl Fortbild Qualitatssich ; 94(5): 373-8, 2000 Jun.
Article in German | MEDLINE | ID: mdl-10939149

ABSTRACT

Pain management by general practitioners often is inadequate. Guidelines for pain management are either not observed or not known at all. Opioids are not prescribed adequately. Differential diagnoses influencing the therapeutic regimen such as drug-induced headache are not sufficiently known. Monotherapies with analgesic drugs are enforced for patients with chronic lower back pain in spite of low efficacy. Improving pain management can be difficult for the general practitioner having no special knowledges or support from pain specialists. However, the general practitioner should remain the patient-coordinator for the patient with chronic pain. Networks with general practitioners and specialised units in the hospital may offer possibilities for improvement of pain management deficits.


Subject(s)
Family Practice/standards , Pain Management , Analgesics/therapeutic use , Chronic Disease , Germany , Guidelines as Topic , Humans , Practice Guidelines as Topic
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