Live birth rate after intrauterine insemination is not different between women with lower quartile versus higher quartile normal range thyroid stimulating hormone levels.

STUDY QUESTION: Does lower quartile normal range thyroid stimulating hormone (TSH) compared to higher quartile normal range in women without thyroid hormone substitution affect live birth rate after a complete IUI treatment series? SUMMARY ANSWER: Lower quartile normal range TSH, in women without thyroid hormone substitution, does not affect live birth rate after a complete intrauterine insemination treatment series compared to higher quartile normal range TSH. WHAT IS KNOWN ALREADY: TSH is historically seen as the most sensitive test for thyroid function. Its distribution is right-skewed. Whether the preconceptional upper reference TSH values in subfertile women should be 2.5 or 4.5 mIU/L is under debate. Studies have shown that IUI patients treated with levothyroxine for TSH levels above 2.5 mIU/L show higher pregnancy rates. However, no adverse outcome is associated with untreated high normal TSH levels studied in first IUI cycles. Thyroid peroxidase antibodies have also impaired outcomes in some studies whereas others have shown an effect only in combination with high normal TSH levels. As a subgroup, patients with unexplained infertility showed increased levels of TSH. This article adds to the value of TSH evaluation and fertility outcome in four quartiles and in the context of a completed IUI treatment modus of a maximum of six inseminations. STUDY DESIGN SIZE DURATION: This is a retrospective cohort study in 909 women undergoing 3588 IUI cycles starting treatment between the first of January 2008 and the first of March 2012. PARTICIPANTS/MATERIALS SETTING METHODS: Women aged 22-45 years with TSH 0.3-4.5 mIU/L without thyroid hormone substitution were included at Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands, an Iodine-sufficient area. The primary endpoint was live birth. Clinical pregnancy, pregnancy loss and ongoing pregnancy were secondary endpoints. Logistic regression was used with the natural logarithm of TSH as a continuous predictor. Chi-square tests and logistic regression were used to compare groups of patients based on TSH values in four quartile TSH groups (0.3-1.21 mIU/L; 1.22-1.75 mIU/L; 1.76-2.34 mIU/L; 2.35-4.5 mIU/L) on basic characteristics and on the endpoints while adjusting for confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Analysis with the natural logarithm of TSH as a continuous variable showed no association with live birth, pregnancy chance or pregnancy loss. There were no differences in any of the outcomes across the quartile TSH level ranges after regression analysis before and after adjusting for age, BMI, use of alcohol, tobacco, use or gonadotrophins, sperm count, diminished ovarian reserve, unexplained infertility and primary or secondary subfertility.The distribution of primary and secondary subfertility and smoking characteristics were remarkably different across the four groups, with proportionally the lowest prevalence of primary subfertility and the highest rate of smoking in the lowest TSH group (0.3-1.20 mIU/L). LIMITATIONS REASONS FOR CAUTION: Unknown values of free thyroxine and thyroid peroxidase antibodies, as well as the retrospective character of the study, limit the clinical interpretability. WIDER IMPLICATIONS OF THE FINDINGS: TSH in the highest quartile range (2.35-4.5 mIU/L) in subfertile women preceding IUI is not associated with a lower live birth rate or rate of clinical and ongoing pregnancy, or with loss of pregnancies, compared to subfertile women with TSH in the lower three quartile groups after complete intrauterine insemination treatment. STUDY FUNDING/COMPETING INTERESTS: The department of Obstetrics and Gynaecology, division of Reproductive Medicine, and of Internal Medicine, division of Endocrinology provided support. There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.

Levels of DNAJB family members (HSP40) correlate with disease onset in patients with spinocerebellar ataxia type 3.

In polyglutamine disorders, the length of the expanded CAG repeat shows a strong inverse correlation with the age at disease onset, yet up to 50% of the variation in age of onset is determined by other additional factors. Here, we investigated whether variations in the expression of heat shock proteins (HSP) are related to differences in the age of onset in patients with spinocerebellar ataxia (SCA)3. Hereto, we analysed the protein expression levels of HSPA1A (HSP70), HSPA8 (HSC70), DNAJB (HSP40) and HSPB1 (HSP27) in fibroblasts from patients and healthy controls. HSPB1 levels were significantly upregulated in fibroblasts from patients with SCA3, but without relation to age of onset. Exclusively for expression of DNAJB family members, a correlation was found with the age of onset independent of the length of the CAG repeat expansion. This indicates that DNAJB members might be contributors to the variation in age of onset and underlines the possible use of DNAJB proteins as therapeutic targets.

Quantitative structure/activity relationship for the rate of conversion of C4-substituted catechols by catechol-1,2-dioxygenase from Pseudomonas putida (arvilla) C1.

The influence of various C4/C5 substituents in catechol (1,2-dihydroxybenzene) derivatives on the overall rate of conversion by catechol-1,2-dioxygenase from Pseudomonas putida (arvilla) C1 was investigated. Using catechol, 4-methylcatechol, 4-fluorocatechol, 4-chlorocatechol, 4-bromocatechol, 4,5-difluorocatechol and 4-chloro-5-fluorocatechol, it could be demonstrated that substituents at the C4 and/or C5 position decrease the rate of conversion, from 62% (4-methylcatechol) down to 0.7% (4-chloro-5-fluorocatechol) of the activity with non-substituted catechol. The inhibition was reversible upon addition of excess catechol for all substrates tested. This indicates that the lower activities are neither due to irreversible inactivation of the enzyme nor to product inhibition. Based on the reaction mechanism proposed in the literature [Que, L. & Ho, R. Y. N. (1996) Chem. Rev. 96, 2606-2624], the nucleophilic reactivity of the catecholate was expected to be an essential characteristic for its conversion by catechol-1,2-dioxygenase. Therefore, the rates of conversion were compared with calculated energies of the highest occupied molecular orbital (E(HOMO)) of the substrates. A clear quantitative relationship (R>0.97) between the ln kcat and the calculated electronic parameter E(HOMO) was obtained. This indicates that the rate-limiting step of the reaction cycle is dependent on the nucleophilic reactivity of the substrate and not sterically hindered by the relatively large bromine or methyl substituents used in the present study. Possible steps in the reaction mechanism determining the overall rate at 20 degrees C are discussed.

Successive mineralization and detoxification of benzo[a]pyrene by the white rot fungus Bjerkandera sp. strain BOS55 and indigenous microflora.

White rot fungi can oxidize high-molecular-weight polycyclic aromatic hydrocarbons (PAH) rapidly to polar metabolites, but only limited mineralization takes place. The objectives of this study were to determine if the polar metabolites can be readily mineralized by indigenous microflora from several inoculum sources, such as activated sludge, forest soils, and PAH-adapted sediment sludge, and to determine if such metabolites have decreased mutagenicity compared to the mutagenicity of the parent PAH. 14C-radiolabeled benzo[a]pyrene was subjected to oxidation by the white rot fungus Bjerkandera sp. strain BOS55. After 15 days, up to 8.5% of the [14C]benzo[a]pyrene was recovered as 14CO2 in fungal cultures, up to 73% was recovered as water-soluble metabolites, and only 4% remained soluble in dibutyl ether. Thin-layer chromatography analysis revealed that many polar fluorescent metabolites accumulated. Addition of indigenous microflora to fungal cultures with oxidized benzo[a]pyrene on day 15 resulted in an initially rapid increase in the level of 14CO2 recovery to a maximal value of 34% by the end of the experiments (>150 days), and the level of water-soluble label decreased to 16% of the initial level. In fungal cultures not inoculated with microflora, the level of 14CO2 recovery increased to 13.5%, while the level of recovery of water-soluble metabolites remained as high as 61%. No large differences in 14CO2 production were observed with several inocula, showing that some polar metabolites of fungal benzo[a]pyrene oxidation were readily degraded by indigenous microorganisms, while other metabolites were not. Of the inocula tested, only PAH-adapted sediment sludge was capable of directly mineralizing intact benzo[a]pyrene, albeit at a lower rate and to a lesser extent than the mineralization observed after combined treatment with white rot fungi and indigenous microflora. Fungal oxidation of benzo[a]pyrene resulted in rapid and almost complete elimination of its high mutagenic potential, as observed in the Salmonella typhimurium revertant test performed with strains TA100 and TA98. Moreover, no direct mutagenic metabolite could be detected during fungal oxidation. The remaining weak mutagenic activity of fungal cultures containing benzo[a]pyrene metabolites towards strain TA98 was further decreased by subsequent incubations with indigenous microflora.

The cancellation method for an accurate determination of an air-bone gap.

For a reliable detection of the bone conduction threshold blocking of the contralateral ear can be necessary but then the noise will affect the threshold in the test ear. To resolve this problem the cancellation method is used. The equalization of air and bone conduction sound level in the inner ear is very accurate, the relation between the intensities has been proved to be linear and independent of noise at the contralateral ear. An application for calibration of the bone conduction vibrator to the head phone is discussed. The benefit of the method for measuring an air-bone gap in an accurate way in patients suffering bilaterally from a severe conductive hearing loss is shown.

Assay of antipyrine and its primary metabolites in plasma, saliva and urine by high-performance liquid chromatography and some preliminary results in man.

A reversed phase system for the HPLC separation of antipyrine and its primary metabolites is described. Based on this system an assay procedure for antipyrine in plasma and saliva was developed with a lowest measurable concentration of 25 ng/ml and precision of +/- 3.6 and +/- 4.5%, respectively. Furthermore, assays for the parent compound, 3-hydroxymethyl-antipyrine, norantipyrine and 4-hydroxy-antipyrine in urine were developed. The lowest measurable concentration for these compounds is about 100 ng/ml except for 3-hydroxymethyl-antipyrine with a lowest measurable concentration of about 200 ng/ml. The precision was established at +/- 3.6 and +/- 5.0% for 3-hydroxymethyl-antipyrine, and antipyrine, respectively, and +/- 7.0 and +/- 3.6% for norantipyrine and 4-hydroxy-antipyrine, respectively. The method was applied to studies on antipyrine metabolism in humans. Following administration of a single dose of 500 mg antipyrine to 5 healthy volunteers, 3.3 +/- 1.2% of the dose was recovered from 48-hour hydrolyzed urine as unchanged drug, 39.7+/- 8.7% as 3-hydroxymethyl-antipyrine, 14.5 +/- 6.8% as norantipyrine and 28.5 +/- 2.2% as 4-hydroxy-antipyrine.

Assay of 3-carboxy-antipyrine in urine by capillary gas chromatography with nitrogen selective detection. Some preliminary results in man.

An assay procedure is described for 3-carboxy-antipyrine in urine using gas chromatography with a support coated open tubular capillary column (Carbowax 20M), a solid injection system and nitrogen selective detection. 3-Carboxy-antipyrine was analyzed after derivatization with diazomethane and using 4-bromo-antipyrine as internal standard. Following extraction of the urine samples with a mixture of organic solvents linear calibration curves were obtained in the concentration range of 1--50 microgram/ml. The precision was established as +/- 5.0% (n = 5), and the lowest measurable concentration was 1 microgram/ml at a signal-to-noise ratio of 10:1. Preliminary results in 5 human volunteers showed that after orl administration of 500 mg antipyrine, 3.3 +/- 0.8% of the dose was excreted as 3-carboxy-antipyrine in 52 hours' urine. The compound was excreted completely in the unconjugated form.