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Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

Objective To investigate hair cortisol concentrations (HCC) monthly in pregnant women and to explore the effect of parity. Design Prospective cohort study from gestational week (GW) 26, at childbirth and postpartum. Setting An antenatal care clinic in southeast Sweden. Sample 390 pregnant women. Methods Cortisol was measured using radioimmunoassay in methanol extracts of ground hair samples. Main outcome measures Hair cortisol concentrations. Results Both primi- and multiparae exhibited an increase in HCC throughout pregnancy. Primiparae had significantly higher HCC in the latter part of the last trimester compared with multiparae (1 month P = 0.003, 2 months P = 0.038). The use of psychotropic medication in the first trimester correlated to HCC postpartum (P < 0.001). HCC in GW 14-17 was associated with HCC in GW 18-21 (primiparae and multiparae, P < 0.001), GW 22-25 (primiparae P = 0.036, multiparae P = 0.033), and 2 months postpartum (primiparae P = 0.049). HCC in GW 18-21 was associated with GW 22-25 in both primiparae (P < 0.001) and multiparae (P < 0.001) as well as 2 months prior to childbirth among primiparae (<0.037). In general, all estimates of HCC in pregnancy and postpartum showed a significant association between HCC for a specific month and the HCC in the previous month (all P < 0.001), except for the association of HCC among primiparae in GW 22-25 and 3 months prior to childbirth. Conclusions Increased cortisol concentrations in hair were observed during pregnancy, which decreased 3 months prior to childbirth in multiparae. The results indicate a quicker suppression of the hypothalamic CRH (corticotropin-releasing hormone) production by placenta CRH in multiparous women.

Background: Diastasis of the rectus abdominis muscle is a common condition. There are no generally accepted criteria for diagnosis or treatment of diastasis of the rectus abdominis muscle, which causes uncertainty for the patient and healthcare providers alike. Methods: The consensus document was created by a group of Swedish surgeons and based on a structured literature review and practical experience. Results: The proposed criteria for diagnosis and treatment of diastasis of the rectus abdominis muscle are as follows: (1) Diastasis diagnosed at clinical examination using a caliper or ruler for measurement. Diagnostic imaging by ultrasound or other imaging modality, should be performed when concurrent umbilical or epigastric hernia or other cause of the patient's symptoms cannot be excluded. (2) Physiotherapy is the firsthand treatment for diastasis of the rectus abdominis muscle. Surgery should only be considered in diastasis of the rectus abdominis muscle patients with functional impairment, and not until the patient has undergone a standardized 6-month abdominal core training program. (3) The largest width of the diastasis should be at least 5 cm before surgical treatment is considered. In case of pronounced abdominal bulging or concomitant ventral hernia, surgery may be considered in patients with a smaller diastasis. (4) When surgery is undertaken, at least 2 years should have elapsed since last childbirth and future pregnancy should not be planned. (5) Plication of the linea alba is the firsthand surgical technique. Other techniques may be used but have not been found superior. Discussion: The level of evidence behind these statements varies, but they are intended to lay down a standard strategy for treatment of diastasis of the rectus abdominis muscle and to enable uniformity of management.

Background/Objectives: Although hundreds of promising substances have been tested in clinical trials, thrombolysis currently remains the only specific pharmacological treatment for ischemic stroke. Poor quality, e.g. low statistical power, in the preclinical studies has been suggested to play an important role in these failures. Therefore, it would be attractive to use animal models optimized to minimize unnecessary mortality and outcome variability, or at least to be able to power studies more exactly by predicting variability and mortality given a certain experimental setup. The possible combinations of methodological parameters are innumerous, and an experimental comparison of them all is therefore not feasible. Design/Method: As an alternative approach, we extracted data from 334 experimental mouse stroke articles and, using a hypothesis-driven meta-analysis, investigated the method parameters' impact on infarct size variability and mortality. Results: The use of Swiss and C57BL6 mice as well as permanent occlusion of the middle cerebral artery rendered the lowest variability of the infarct size while the emboli methods increased variability. The use of Swiss mice increased mortality. Conclusions: Our study offers guidance for researchers striving to optimize mouse stroke models.

This corrects the article Development of Salivary Cortisol Circadian Rhythm and Reference Intervals in Full-Term Infants DO1:10.1371/journal.pone.0129502

Rodent models constitute a cornerstone in the elucidation of the effects and biological mechanisms of 17β-estradiol. However, a thorough assessment of the methods for long-term administration of 17β-estradiol to mice is lacking. The fact that 17β-estradiol has been demonstrated to exert different effects depending on dose emphasizes the need for validated administration regimens. Therefore, 169 female C57BL/6 mice were ovariectomized and administered 17β-estradiol using one of the two commonly used subcutaneous methods; slow-release pellets (0.18 mg, 60-day release pellets; 0.72 mg, 90-day release pellets) and silastic capsules (with/without convalescence period, silastic laboratory tubing, inner/outer diameter: 1.575/3.175 mm, filled with a 14 mm column of 36 μg 17β-estradiol/mL sesame oil), or a novel peroral method (56 μg 17β-estradiol/day/kg body weight in the hazelnut cream Nutella). Forty animals were used as ovariectomized and intact controls. Serum samples were obtained weekly for five weeks and 17β-estradiol concentrations were measured using radioimmunoassay. The peroral method resulted in steady concentrations within--except on one occasion--the physiological range and the silastic capsules produced predominantly physiological concentrations, although exceeding the range by maximum a factor three during the first three weeks. The 0.18 mg pellet yielded initial concentrations an order of magnitude higher than the physiological range, which then decreased drastically, and the 0.72 mg pellet produced between 18 and 40 times higher concentrations than the physiological range during the entire experiment. The peroral method and silastic capsules described in this article constitute reliable modes of administration of 17β-estradiol, superior to the widely used commercial pellets.

Hormone replacement after menopause has in recent years been the subject of intense scientific debate and public interest and has sparked intense research efforts into the biological effects of estrogens and progestagens. However, there are reasons to believe that the doses used and plasma concentrations produced in a large number of studies casts doubt on important aspects of their validity. The concept of hormesis states that a substance can have diametrically different effects depending on the concentration. Even though estrogens and progestagens have proven prone to this kind of dose-response relation in a multitude of studies, the phenomenon remains clearly underappreciated as exemplified by the fact that it is common practice to only use one hormone dose in animal experiments. If care is not taken to adjust the concentrations of estrogens and progestagens to relevant biological conditions, the significance of the results may be questionable. Our aim is to review examples of female sexual steroids demonstrating bidirectional dose-response relations and to discuss this in the perspective of hormesis. Some examples are highlighted in detail, including the effects on cerebral ischemia, inflammation, cardiovascular diseases and anxiety. Hopefully, better understanding of the hormesis phenomenon may result in improved future designs of studies of female sexual steroids., cited By 5

The impact of exposure of the intestinal mucosa to acid and hyperosmolal solutions on the release of the inhibitory gut peptides somatostatin (SOM), neurotensin (NT) and vasoactive intestinal peptide (VIP) was studied in conscious rats during pentagastrin-stimulated gastric acid secretion. The animals were equipped with a chronic gastric fistula to measure acid secretion and a jejunal Thiry–Vella loop for intestinal challenge with saline, hydrochloric acid (HCl, 200 mmol L− 1) or hyperosmolal polyethylene glycol (PEG, 1200 mOsm kg− 1). Gut peptide concentrations were measured in intestinal perfusates, and in plasma samples collected during stimulated acid secretion, and at the end of experiments with luminal challenge of the loops. After pentagastrin-stimulation acid secretion was dose-dependently inhibited by intravenous administration of the gastrin receptor antagonist gastrazole, as well as ranitidine and esomeprazole by maximally 73 ± 10%; 95 ± 3%; 90 ± 10%, respectively. Acid perfusion of the Thiry–Vella loop caused a prominent release of SOM both to the lumen (from 7.2 ± 5.0 to 1279 ± 580 pmol L− 1) and to the circulation (from 18 ± 5.2 to 51 ± 9.0 pmol L− 1) simultaneously with an inhibition of gastric acid secretion. The release of NT and VIP was not affected to the same extent. PEG perfusion of the loop caused a release of SOM as well as NT and VIP, but less. Simultaneously acid secretion was slightly decreased. In conclusion, intestinal perfusion with acid or hyperosmolal solutions mainly releases SOM, which seems to exert a major inhibitory action in the gut, as shown by inhibition of acid secretion. The other peptides NT and VIP also participate in this action but to a much lesser degree. The operative pathways of these gut peptides hence involve both endocrine (SOM) and paracrine actions (SOM, NT, VIP) in order to exert inhibitory functions on the stomach. The inhibitory action of gastrazole, was in a similar range as that of SOM implying that physiolog

Glucagon-like peptide-1 (GLP-1) is released after food intake to act as an incretin. GLP-1 also inhibits gastric emptying and increases satiety. In rats, GLP-1 inhibits small bowel motility. Our aim was to study the effects of GLP-1 on gastrointestinal motility in healthy subjects and patients with irritable bowel syndrome (IBS). Antro-duodeno-jejunal manometry was carried out during a 4-h control period with saline, followed by a 4-h period with intravenous GLP-1 (healthy: 0.7 and 1.2 pmol kg(-1) min(-1) (n = 16); IBS, 1.2 and 2.5 pmol kg(-1) min(-1) (n = 14). Plasma was analysed for GLP-1 and gut hormones, and gut tissue expression of GLP-1 receptor was studied. In healthy subjects, GLP-1 0.7 pmol kg(-1) min(-1) reduced the migrating motor complexes (MMCs) from a median of 2 (range 2-3) to 0.5 (0-2), and motility index from 4.9 +/- 0.1 to 4.3 +/- 0.3 ln Sigma(mmHg*s min(-1)) in jejunum, while GLP-1 1.2 pmol kg(-1) min(-1) diminished MMCs from 2 (2-3) to 1.5 (1-2.5), and motility index from 5.2 +/- 0.2 to 4.4 +/- 0.2. In IBS patients, GLP-1 1.2 pmol kg(-1) min(-1) reduced the MMCs from 2.5 (2-3.5) to 1 (0-1.5) without affecting motility index. At 2.5 pmol kg(-1) min(-1) GLP-1 decreased MMCs from 2 (1.5-3) to 1 (0.5-1.5), and motility index from 5.2 +/- 0.2 to 4.0 +/- 0.5. Motility responses to GLP-1 were similar in antrum and duodenum. Presence of the GLP-1 receptor in the gut was verified by reverse transcriptase PCR. In conclusion, the gut peptide GLP-1 decreases motility in the antro-duodeno-jejunal region and inhibits the MMC in healthy subjects and IBS patients.

Udgivelsesdato: 2008/6

The about 400 million individuals worldwide suffering from a hereditary deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD) may experience different degrees of haemolytic anaemia. Haemoglobin is present in very high concentrations in the erythrocyte cytoplasm, at risk of falling out of solution if the internal environment or the haemoglobin itself is changed. G6PD is a crucial enzyme producing reduced glutathione in the erythrocyte cytoplasm for the purpose of protecting haemoglobin against oxidative damage. The presence of unopposed oxidizing agents leading to oxidation of the sulfhydryl bridges between parts of the haemoglobin molecule decrease the solubility of haemoglobin, leading to precipitations called Heinz bodies. The laboratory investigation of G6PD deficiency is commonly done by a quantitative spectrophotometric analysis or by a rapid fluorescent spot test detecting the generation of NADPH from NADP. Genetic tests based on polymerase chain reaction detect specific mutations and may be used for population screening, family studies, or prenatal diagnosis.

BACKGROUND: Little is known about factors related to prognosis in patients with carcinoid disease. In this study we have tried to identify such factors. PATIENTS AND METHODS: We have evaluated 301 consecutive carcinoid patients (256 midgut, 39 foregut and six hindgut) referred during 15 years for medical treatment with respect to tumor distribution, hormone production, prognostic factors and survival. RESULTS: Survival was significantly shorter in midgut carcinoid patients with > or = 5 liver metastases or with high levels of urinary 5-hydroxyindoleacetic acid, plasma chromogranin A or neuropeptide K. By univariate analysis, these variables together with the presence of carcinoid syndrome were related to a higher risk of dying. In multivariate analyses, performed in the 71 patients with full information on all variables, advanced age and plasma chromogranin A > 5000 micrograms/l were independent predictors of overall survival. CONCLUSIONS: Poor prognostic factors for midgut carcinoid patients were multiple liver metastases, presence of carcinoid syndrome and high levels of the tumor markers studied. In this study the only independent predictors of bad prognosis in midgut, carcinoid patients were advanced age, which however is inherently related to overall survival, and plasma chromogranin A > 5000 micrograms/l. Thus, chromogranin A may prove to be an important prognostic marker for patients with carcinoid tumors.

The effects of epithelium removal were studied on the contraction induced by Ca2+ in K(+)-depolarizing solution, and by the calcium ionophore A 23187 in guinea-pig isolated tracheal strips. Epithelium removal reduced the maximal response to Ca2+ in K(+)-depolarizing solution and caused a significant shift to the right of the Ca2+ concentration-response curves. The contraction induced by the calcium ionophore A 23187 (10(-6) M) was also markedly reduced by epithelium removal. These results suggest the occurrence of an epithelium-derived contracting factor. The effects of hexamethonium, atropine, spantide and thiorphan showed that acetylcholine and neurokinins play a minor role in the Ca(2+)-induced contraction. The epithelium-dependent potentiation of the calcium- and of the A 23187-induced contractions was inhibited by an antibody selective for rat calcitonin gene-related peptide (rCGRP alpha). Therefore, CGRP-like immunoreactive material may be part of the epithelium-dependent contracting factor of guinea-pig trachea. Comparison of concentration-response curves for rCGRP alpha in epithelium-free and in intact guinea-pig tracheal strips suggests that an epithelium-dependent contracting factor may be mobilized by CGRP.

Plasma levels of chromogranin A + B, neuropeptide Y and catecholamines were analysed before, during and after surgery in seven patients with pheochromocytoma. The aim of the study was to determine the diagnostic sensitivity of these plasma amines and peptides, and to investigate their peroperative fluctuations. Chromogranin A + B in plasma was increased preoperatively in all patients, showed no significant increase during surgery, and normalized postoperatively. Neuropeptide Y, which alone can induce hypertension, was present in high levels in plasma from three patients preoperatively, increased further in four patients during surgery, and was postoperatively low in all patients. Fractionated plasma catecholamines were increased in five patients before surgery, increased in all patients during tumour dissection, and normalized postoperatively. It may be concluded that plasma chromogranin A + B exhibited as high a sensitivity for pheochromocytoma as fractionated urinary catecholamines in the patients studied.

Capsaicin (10(-9) to 10(-5) M) contracted guinea-pig tracheal strips. Epithelium-containing tracheal strips developed a maximum active tension which was significantly higher than that observed in epithelium-free strips. Anti-CGRP (calcitonin gene-related peptide) serum blocked the epithelium-dependent potentiation of the capsaicin-induced contraction in the intact tracheal strips, without affecting the response of the epithelium-free strips. This result suggests the occurrence of an epithelium-dependent release of CGRP. This same serum markedly reduced the contraction induced by exogenous rat CGRP in both intact and epithelium-free tracheal strips. In epithelium-free tracheal strips, capsaicin-induced contraction was abolished by spantide (10(-6) and 10(-5) M), a substance P antagonist, but, in intact tracheal strips, spantide did not abolish the capsaicin-induced contraction, showing that both CGRP and substance P release are directly induced by capsaicin. Moreover, the contractile responses to rat CGRP of intact tracheal strips from guinea pig suggest that CGRP itself might be able to release a contracting factor from the airway epithelium. Therefore, CGRP originating from the airway epithelium may play a major role in the control of airway smooth muscle tone.