2,864 research outputs found
A method for accurate measurement of GFR in conscious, spontaneously voiding rats
A method for accurate measurement of GFR in conscious, spontaneously voiding rats. Renal function measurement by clearance methods relies on accurately timed urine collection. In small experimental animals, renal function measurement is usually performed under anesthesia and/or with the application of bladder catheters to ensure accurate urine collection. To avoid both anesthesia and the need for bladder catheters we developed a method to measure glomerular filtration rate (GFR) in spontaneously voiding conscious rats. GFR was measured as the urinary clearance of constantly infused 125I-iothalamate. To correct for incomplete bladder emptying, urinary clearance of 125I-iothalamate was multiplied by the ratio of plasma and urinary clearance of simultaneously infused 131I-hippuran, a correction method that has been previously validated in humans. Reproducibility of the technique was evaluated by analysis of the results of four consecutive clearance periods during the day (intra-assay variation) in a group of 17 rats and of two consecutive clearance periods on two or three separate days in a group of 20 rats (inter-assay variation), all with normal renal function. Application of the correction method reduced the intra-assay coefficient of variation (mean ± SD) from 37.4 ± 14.3 to 5.4 ± 2.3% (P < 0.05). The mean inter-assay coefficient of variation fell slightly from 23.4 ± 10.3 to 11.0 ± 7.2% (P < 0.10). In rats with moderately impaired renal function (N = 8) the intra-assay variation fell from 27.9 ± 20.7 to 2.7 ± 1.6% (P < 0.05). Our data show that this correction method is a useful technique to assess renal function in conscious, spontaneously voiding rats
Prevalence of Peyronie and Ledderhose Diseases in a Series of 730 Patients with Dupuytren Disease
BACKGROUND: Dupuytren, Peyronie, and Ledderhose diseases are related fibroproliferative disorders characterized by abnormalities in the connective tissue of the palm of the hand, the tunica albuginea of the penis, and the sole of the foot, respectively. Concomitant prevalence rates of these diseases have only been described in a few small populations. This article aims to report on a large population and to raise awareness in surgeons treating Dupuytren disease for concurring related fibroproliferative disorders. METHODS: Patients diagnosed as having Dupuytren disease were recruited from outpatient clinics in the northern part of the Netherlands from 2007 to 2016. Questionnaires concerning demographics, clinical characteristics, the coexistence of Ledderhose and/or Peyronie diseases, and other factors were filled in by the participants and by plastic surgeons. RESULTS: For 730 men with Dupuytren disease, the surgeons' reported prevalence rate of Peyronie disease was 7.8 percent and of Ledderhose disease was 16.1 percent. The participants themselves reported prevalence rates of 8.8 percent for Peyronie disease and of 22.0 percent for Ledderhose disease. CONCLUSIONS: In the Dupuytren patient cohort, the prevalence of Peyronie disease was lower than that described in the literature. The prevalence of Ledderhose disease corresponded with the rates from the literature. However, both were underreported by plastic surgeons, which calls for a rise in awareness, recognition, and referral to a urologist when the conditions are bothersome or symptomatic
UV-Optical Pixel Maps of Face-On Spiral Galaxies -- Clues for Dynamics and Star Formation Histories
UV and optical images of the face-on spiral galaxies NGC 6753 and NGC 6782
reveal regions of strong on-going star formation that are associated with
structures traced by the old stellar populations. We make NUV--(NUV-I) pixel
color-magnitude diagrams (pCMDs) that reveal plumes of pixels with strongly
varying NUV surface brightness and nearly constant I surface brightness. The
plumes correspond to sharply bounded radial ranges, with (NUV-I) at a given NUV
surface brightness being bluer at larger radii. The plumes are parallel to the
reddening vector and simple model mixtures of young and old populations, thus
neither reddening nor the fraction of the young population can produce the
observed separation between the plumes. The images, radial surface-brightness,
and color plots indicate that the separate plumes are caused by sharp declines
in the surface densities of the old populations at radii corresponding to disk
resonances. The maximum surface brightness of the NUV light remains nearly
constant with radius, while the maximum I surface brightness declines sharply
with radius. An MUV image of NGC 6782 shows emission from the nuclear ring. The
distribution of points in an (MUV-NUV) vs. (NUV-I) pixel color-color diagram is
broadly consistent with the simple mixture model, but shows a residual trend
that the bluest pixels in (MUV-NUV) are the reddest pixels in (NUV-I). This may
be due to a combination of red continuum from late-type supergiants and [SIII]
emission lines associated with HII regions in active star-forming regions. We
have shown that pixel mapping is a powerful tool for studying the distribution
and strength of on-going star formation in galaxies. Deep, multi-color imaging
can extend this to studies of extinction, and the ages and metallicities of
composite stellar populations in nearby galaxies.Comment: LaTeX with AASTeX style file, 29 pages with 12 figures (some color,
some multi-part). Accepted for publication in The Astrophysical Journa
Star Clusters in the Nearby Late-Type Galaxy NGC 1311
Ultraviolet, optical and near infrared images of the nearby (D ~ 5.5 Mpc) SBm
galaxy NGC 1311, obtained with the Hubble Space Telescope, reveal a small
population of 13 candidate star clusters. We identify candidate star clusters
based on a combination of their luminosity, extent and spectral energy
distribution. The masses of the cluster candidates range from ~1000 up to
~100000 Solar masses, and show a strong positive trend of larger mass with
increasing with cluster age. Such a trend follows from the fading and
dissolution of old, low-mass clusters, and the lack of any young super star
clusters of the sort often formed in strong starbursts. The cluster age
distribution is consistent with a bursting mode of cluster formation, with
active episodes of age ~10 Myr, ~100 Myr and ~1 Gyr. The ranges of age and mass
we probe are consistent with those of the star clusters found in quiescent
Local Group dwarf galaxies.Comment: 21 pages, 11 figures, accepted by A
What you see is (not) what you get:tools for a non-radiologist to evaluate image quality in lung cancer
Atorvastatin pleiotropically decreases intraplaque angiogenesis and intraplaque haemorrhage by inhibiting ANGPT2 release and VE-Cadherin internalization
Funding This work was supported by a grant from the European Union, MSCA joint doctoral project MoGlyNet [675527].Peer reviewedPublisher PD
Assessing hearing loss in older adults with a single question and person characteristics; Comparison with pure tone audiometry in the Rotterdam Study
INTRODUCTION: Hearing loss (HL) is a frequent problem among the elderly and has been studied in many cohort studies. However, pure tone audiometry-the gold standard-is rather time-consuming and costly for large population-based studies. We have investigated if self-reported hearing loss, using a multiple choice question, can be used to assess HL in absence of pure tone audiometry. METHODS: This study was performed within 4,906 participants of the Rotterdam Study. The question (in Dutch) that was investigated was: 'Do you have any difficulty with your hearing (without hearing aids)?'. The answer options were: 'never', 'sometimes', 'often' and 'daily'. Mild hearing loss or worse was defined as PTA0.5-4(Pure Tone Average 0.5, 1, 2 & 4 kHz) â„20dBHL and moderate HL or worse as â„35dBHL. A univariable linear regression model was fitted with the PTA0.5-4 and the answer to the question. Subsequently, sex, age and education were added in a multivariable linear regression model. The ability of the question to classify HL, accounting for sex, age and education, was explored through logistic regression models creating prediction estimates, which were plotted in ROC curves. RESULTS: The variance explained (R2) by the univariable regression was 0.37, which increased substantially after adding age (R2 = 0.60). The addition of sex and educational level, however, did not alter the R2 (0.61). The ability of the question to classify hearing loss, reflec
Feasibility of Doppler Ultrasound for Cortical Cerebral Blood Flow Velocity Monitoring During Major Non-cardiac Surgery of Newborns
Contra-lateral bone loss at the distal radius in postmenopausal women after a distal radius fracture:A two-year follow-up HRpQCT study
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