We have compared three different methods of treating symptomatic non-traumatic tears of the supraspinatus tendon in patients above 55 years of age. A total of 180 shoulders (173 patients) with ...supraspinatus tendon tears were randomly allocated into one of three groups (each of 60 shoulders); physiotherapy (group 1), acromioplasty and physiotherapy (group 2) and rotator cuff repair, acromioplasty and physiotherapy (group 3). The Constant score was assessed and followed up by an independent observer pre-operatively and at three, six and twelve months after the intervention. Of these, 167 shoulders were available for assessment at one year (follow-up rate of 92.8%). There were 55 shoulders in group 1 (24 in males and 31 in females, mean age 65 years (55 to 79)), 57 in group 2 (29 male and 28 female, mean age 65 years (55 to 79)) and 55 shoulders in group 3 (26 male and 29 female, mean age 65 years (55 to 81)). There were no between-group differences in the Constant score at final follow-up: 74.1 (sd 14.2), 77.2 (sd 13.0) and 77.9 (sd 12.1) in groups 1, 2 and 3, respectively (p = 0.34). The mean change in the Constant score was 17.0, 17.5, and 19.8, respectively (p = 0.34). These results suggest that at one-year follow-up, operative treatment is no better than conservative treatment with regard to non-traumatic supraspinatus tears, and that conservative treatment should be considered as the primary method of treatment for this condition.
Deep Learning (DL) methods are powerful analytical tools for microscopy and can outperform conventional image processing pipelines. Despite the enthusiasm and innovations fuelled by DL technology, ...the need to access powerful and compatible resources to train DL networks leads to an accessibility barrier that novice users often find difficult to overcome. Here, we present ZeroCostDL4Mic, an entry-level platform simplifying DL access by leveraging the free, cloud-based computational resources of Google Colab. ZeroCostDL4Mic allows researchers with no coding expertise to train and apply key DL networks to perform tasks including segmentation (using U-Net and StarDist), object detection (using YOLOv2), denoising (using CARE and Noise2Void), super-resolution microscopy (using Deep-STORM), and image-to-image translation (using Label-free prediction - fnet, pix2pix and CycleGAN). Importantly, we provide suitable quantitative tools for each network to evaluate model performance, allowing model optimisation. We demonstrate the application of the platform to study multiple biological processes.
Several recent papers claim the detection of a near-infrared (NIR) extragalactic background light (EBL) intensity at 1.25–4 μm that exceeds the integrated light of galaxies by factors of >3. When ...combined with a claimed optical detection of the EBL at 0.80 μm the EBL excess emission spectrum has a discontinuity at ∼1 μm. This discontinuity has given rise to an interpretation in terms of ultraviolet radiation emanating from the first generation of massive stars at redshifts of 7–20 (so-called Population III stars). The interpretation of the NIR excess emission as being of extragalactic origin depends crucially on the model used in the subtraction of the zodiacal light (ZL), the dominant foreground contaminant. We estimate the ZL at 0.80 μm using on the one hand the measurement by Bernstein et al., with corrections for some omitted effects of atmospheric scattering and calibration, and on the other hand the model of Kelsall et al. There is in neither case any evidence for a step in the EBL at ∼1 μm. We emphasize that in order to avoid systematic effects it is essential to use the same ZL model for both the NIR (1.25–4 μm) and optical (0.80 μm) data. We emphasize, however, that our analysis does not allow a statement on the overall level of the NIR EBL. The contribution of the diffuse galactic light to the ‘EBL excess’ emission is estimated. It is found to be significant at 3–4 μm and should be carefully evaluated in future measurements which aim at detecting an EBL signal at the level of ∼10 nW m−2 sr−1, that is, at the level of the integrated light of (known) galaxies.
Filopodia are thin, actin-rich plasma-membrane protrusions that function as antennae for cells to probe their environment. Consequently, filopodia have an important role in cell migration, neurite ...outgrowth and wound healing and serve as precursors for dendritic spines in neurons. The initiation and elongation of filopodia depend on the precisely regulated polymerization, convergence and crosslinking of actin filaments. The increased understanding of the functions of various actin-associated proteins during the initiation and elongation of filopodia has provided new information on the mechanisms of filopodia formation in distinct cell types.
Background
Myopathy, probably caused by 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase inhibition in skeletal muscle, rarely occurs in patients taking statins. This study was designed to assess the ...effect of high‐dose statin treatment on cholesterol and ubiquinone metabolism and mitochondrial function in human skeletal muscle.
Methods
Forty‐eight patients with hypercholesterolemia (33 men and 15 women) were randomly assigned to receive 80 mg/d of simvastatin (n = 16), 40 mg/d of atorvastatin (n = 16), or placebo (n = 16) for 8 weeks. Plasma samples and muscle biopsy specimens were obtained at baseline and at the end of the follow‐up.
Results
The ratio of plasma lathosterol to cholesterol, a marker of endogenous cholesterol synthesis, decreased significantly by 66% in both statin groups. Muscle campesterol concentrations increased from 21.1 ± 7.1 nmol/g to 41.2 ± 27.0 nmol/g in the simvastatin group and from 22.6 ± 8.6 nmol/g to 40.0 ± 18.7 nmol/g in the atorvastatin group (P = .005, repeated‐measurements ANOVA). The muscle ubiquinone concentration was reduced significantly from 39.7 ± 13.6 nmol/g to 26.4 ± 7.9 nmol/g (P = .031, repeated‐measurements ANOVA) in the simvastatin group, but no reduction was observed in the atorvastatin or placebo group. Respiratory chain enzyme activities were assessed in 6 patients taking simvastatin with markedly reduced muscle ubiquinone and in matched subjects selected from the atorvastatin (n = 6) and placebo (n = 6) groups. Respiratory chain enzyme and citrate synthase activities were reduced in the patients taking simvastatin.
Conclusions
High‐dose statin treatment leads to changes in the skeletal muscle sterol metabolism. Furthermore, aggressive statin treatment may affect mitochondrial volume.
Clinical Pharmacology & Therapeutics (2005) 78, 60–68; doi: 10.1016/j.clpt.2005.03.006
MRI Findings in Acute Tonsillar Infections Heikkinen, J; Nurminen, J; Velhonoja, J ...
American journal of neuroradiology,
02/2022, Letnik:
43, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Previous literature is vague on the prevalence and exact nature of abscesses in tonsillar infections, ranging from intratonsillar and peritonsillar collections to deep extension involving the ...parapharyngeal and retropharyngeal spaces. MR imaging has excellent diagnostic accuracy in detecting neck infections and can potentially clarify this issue. We sought to characterize the spectrum of MR imaging findings regarding tonsillar infections.
We conducted a retrospective cohort study of emergency neck MR imaging scans of patients with tonsillar infections. Imaging data were assessed in terms of signs of infection and the location of abscesses and were compared with clinical findings, final diagnoses, and surgical findings as reference standards.
The study included 132 patients with tonsillar infection. Of these, 110 patients (83%) had ≥1 abscess (99 unilateral, 11 bilateral; average volume, 3.2 mL). Most abscesses were peritonsillar, and we found no evidence of intratonsillar abscess. Imaging showed evidence of parapharyngeal and retropharyngeal extension in 36% and 10% of patients, respectively. MR imaging had a high positive predictive value for both abscesses (0.98) and deep extension (0.86). Patients with large abscesses and widespread edema patterns had a more severe course of illness.
Emergency neck MR imaging can accurately describe the extent and nature of abscess formation in tonsillar infections.
In contrast to the highly dynamic actin cytoskeleton in non-muscle cells, actin filaments in muscle sarcomeres are thought to be relatively stable and undergo dynamics only at their ends. However, ...many proteins that promote rapid actin dynamics are also expressed in striated muscles. We show that a subset of actin filaments in cardiomyocyte sarcomeres displays rapid turnover. Importantly, we found that turnover of these filaments depends on contractility of the cardiomyocytes. Studies using an actin-polymerization inhibitor suggest that the pool of dynamic actin filaments is composed of filaments that do not contribute to contractility. Furthermore, we provide evidence that ADF/cofilins, together with myosin-induced contractility, are required to disassemble non-productive filaments in developing cardiomyocytes. These data indicate that an excess of actin filaments is produced during sarcomere assembly, and that contractility is applied to recognize non-productive filaments that are subsequently destined for depolymerization. Consequently, contractility-induced actin dynamics plays an important role in sarcomere maturation.
Aposematic animals advertise their toxicity or unpalatability with bright warning coloration. However, acquiring and maintaining chemical defenses can be energetically costly, and consequent ...associations with other important traits could shape chemical defense evolution. Here, we have tested whether chemical defenses are involved in energetic trade‐offs with other traits, or whether the levels of chemical defenses are condition dependent, by studying associations between biosynthesized cyanogenic toxicity and a suite of key life‐history and fitness traits in a Heliconius butterfly under a controlled laboratory setting. Heliconius butterflies are well known for the diversity of their warning color patterns and widespread mimicry and can both sequester the cyanogenic glucosides of their Passiflora host plants and biosynthesize these toxins de novo. We find energetically costly life‐history traits to be either unassociated or to show a general positive association with biosynthesized cyanogenic toxicity. More toxic individuals developed faster and had higher mass as adults and a tendency for increased lifespan and fecundity. These results thus indicate that toxicity level of adult butterflies may be dependent on individual condition, influenced by genetic background or earlier conditions, with maternal effects as one strong candidate mechanism. Additionally, toxicity was higher in older individuals, consistent with previous studies indicating accumulation of toxins with age. As toxicity level at death was independent of lifespan, cyanogenic glucoside compounds may have been recycled to release resources relevant for longevity in these long‐living butterflies. Understanding the origins and maintenance of variation in defenses is necessary in building a more complete picture of factors shaping the evolution of aposematic and mimetic systems.
Understanding the origins and maintenance of variation in defenses is necessary in building a more complete picture of factors shaping the evolution of aposematic and mimetic systems. We studied associations between biosynthesized cyanogenic toxicity and a suite of key life‐history and fitness traits in a Heliconius butterfly under a controlled laboratory setting. Our data adds to evidence suggesting that life‐history trade‐offs involving negative associations with chemical defense traits are not particularly common in aposematic herbivores, but that variation in chemical defense levels could be introduced by condition dependent investments into defense compound production.
Rho family GTPases regulate diverse cellular events, such as cell motility, polarity, and vesicle traffic. Although a wealth of data exists on the canonical Rho GTPases RhoA, Rac1, and Cdc42, several ...other family members remain poorly studied. In B cells, we recently demonstrated a critical role for Cdc42 in plasma cell differentiation. In this study, we focus on a close homolog of Cdc42, TC10 (also known as RhoQ), and investigate its physiological role in B cells. By generating a TC10-deficient mouse model, we show that despite reduced total B cell numbers, B cell development in these mice occurs normally through distinct developmental stages. Upon immunization, IgM levels were reduced and, upon viral infection, germinal center responses were defective in TC10-deficient mice. BCR signaling was mildly affected, whereas cell migration remained normal in TC10-deficient B cells. Furthermore, by generating a TC10/Cdc42 double knockout mouse model, we found that TC10 can compensate for the lack of Cdc42 in TLR-induced cell activation and proliferation, so the two proteins play partly redundant roles. Taken together, by combining in vivo and in vitro analysis using TC10-deficient mice, we define the poorly studied Rho GTPase TC10 as an immunomodulatory molecule playing a role in physiological B cell responses.
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