The complexity of kidney disease and diagnosing it - cystatin C, selective glomerular hypofiltration syndromes and proteome regulation

Estimation of kidney function is often part of daily clinical practice, mostly done by using the endogenous glomerular filtration rate (GFR)-markers creatinine or cystatin C. A recommendation to use both markers in parallel in 2010 has resulted in new knowledge concerning the pathophysiology of kidney disorders by the identification of a new set of kidney disorders, selective glomerular hypofiltration syndromes. These syndromes, connected to strong increases in mortality and morbidity, are characterized by a selective reduction in the glomerular filtration of 5-30 kDa molecules, such as cystatin C, compared to the filtration of small molecules <1 kDa dominating the glomerular filtrate, for example water, urea and creatinine. At least two types of such disorders, shrunken or elongated pore syndrome, are possible according to the pore model for glomerular filtration. Selective glomerular hypofiltration syndromes are prevalent in investigated populations, and patients with these syndromes often display normal measured GFR or creatinine-based GFR-estimates. The syndromes are characterized by proteomic changes promoting the development of atherosclerosis, indicating antibodies and specific receptor-blocking substances as possible new treatment modalities. Presently, the KDIGO guidelines for diagnosing kidney disorders do not recommend cystatin C as a general marker of kidney function and will therefore not allow the identification of a considerable number of patients with selective glomerular hypofiltration syndromes. Furthermore, as cystatin C is uninfluenced by muscle mass, diet or variations in tubular secretion and cystatin C-based GFR-estimation equations do not require controversial race or sex terms, it is obvious that cystatin C should be a part of future KDIGO guidelines.

Cancer associated proteins in blood plasma: Determining normal variation

Protein biomarkers have the potential to improve diagnosis, stratification of patients into treatment cohorts, follow disease progression and treatment response. One distinct group of potential biomarkers comprises proteins which have been linked to cancer, known as cancer associated proteins (CAPs). We determined the normal variation of 86 CAPs in 72 individual plasma samples collected from ten individuals using SRM mass spectrometry. Samples were collected weekly during 5 weeks from ten volunteers and over one day at nine fixed time points from three volunteers. We determined the degree of the normal variation depending on interpersonal variation, variation due to time of day, and variation over weeks and observed that the variation dependent on the time of day appeared to be the most important. Subdivision of the proteins resulted in two predominant protein groups containing 21 proteins with relatively high variation in all three factors (day, week and individual), and 22 proteins with relatively low variation in all factors. We present a strategy for prioritizing biomarker candidates for future studies based on stratification over their normal variation and have made all data publicly available. Our findings can be used to improve selection of biomarker candidates in future studies and to determine which proteins are most suitable depending on study design.

A meta-analysis on the correlation between ovarian activity and the incidence of intermenstrual bleeding during low-dose oral contraceptive use

We aimed to evaluate potential correlation between ovarian activity during use of combined oral contraceptives and the incidence of intermenstrual bleeding. Data from seven prospective clinical studies with five different combined low-dose oral contraceptives were retrospectively analyzed to determine ovarian activity measured by the Hoogland Score (follicle diameter and endogenous hormone levels) and cycle control. A total of 227 young fertile women were evaluated over three treatment cycles each. Women with intermenstrual bleeding had statistically significantly higher estradiol levels than those without intermenstrual bleeding. Also, women with intermenstrual bleeding had significantly larger follicle-like structures than those without intermenstrual bleeding. For example, in the second treatment cycle the difference of the mean follicle diameters between women without intermenstrual bleeding (12.5 mm) and women with spotting (16.9 mm) or breakthrough bleeding (16.1 mm) was statistically significant (p = 0.0179). Less than 17% of women with Hoogland Score 1, 2 or 3 (low ovarian activity) reported intermenstrual bleeding. On the other hand, 35.2% of women with Hoogland Score 4 (active follicle-like structures) reported intermenstrual bleeding. The association between bleeding and Hoogland Score was statistically significant (p < 0.0011). The findings of this retrospective analysis provide evidence that high ovarian suppression is positively correlated with improved cycle control in terms of less frequent intermenstrual bleeding - slight and heavy.

A new bronchial blocker tube for one-lung ventilation

One-lung ventilation is used to facilitate thoracic and cardiac surgery. This article describes the development and clinical use of a new device, the bronchial blocker tube, to establish one-lung ventilation. The bronchial blocker tube has two circular lumen joined together, one for ventilation and one for acceptance of a bronchial blocker. In this setting, the bronchial blocker is a separate device which is replaceable, rotatable, and removable. In the authors' experience, the bronchial blocker tube was effective and easy to use.

Inversion (6)(p23q15) as the sole anomaly in a low-grade intraosseous osteosarcoma

We describe the finding of an inversion (6)(p23q15) as the sole anomaly in short-term cultures from an intraosseous low-grade osteosarcoma.

Cloning of novel Wilms tumor gene (WT1) cDNAs; evidence for antisense transcription of WT1

WT1 is a tumor suppressor gene that has been implicated in Wilms tumor, and is expressed in cells of mesodermal origin. The Wit-1 gene is located approximately 2 kb from the WT1 gene, and is expressed coordinately with WT1. WT1 and Wit-1 are bi-directionally transcribed from the same promoter region. We have screened a human fetal kidney cDNA library to identify novel WT1 cDNA clones. Here we report the cloning of cDNA clones which span part of intron 1 of WT1, exon 1, upstream sequences between WT1 and Wit-1 and part of the Wit-1 gene. Northern blot and RNAase protection analysis using subcloned fragments of the cDNAs corresponding to regions from within intron 1 of WT1 suggest that a 7-10 Kb RNA is expressed in human fetal kidney, which overlaps with WT1 and is transcribed in the same direction as Wit-1.

Screened hydrogenic radial integrals

The screened hydrogenic radial integral both for discrete-discrete and discrete-continuum transitions is expressed in forms suitable for obtaining closed-form expressions for specific transitions. Two effective charge parameters Zi and Zf, respectively, for the initial state and for the final state are retained in these formulas. As examples, explicit expressions for a few transitions are derived and a method for obtaining a series for a discrete-discrete radial integral, suitable for large final-state principal quantum numbers, is indicated.