In the literature, it has been reported that the mechanical output per leg is less in two-leg jumps than in one-leg jumps. This so-called bilateral deficit has been attributed to a reduced neural ...drive to muscles in two-leg jumps. The purpose of the present study was to investigate the possible contribution of nonneural factors to the bilateral deficit in jumping. We collected kinematics, ground reaction forces, and electromyograms of eight human subjects performing two-leg and one-leg (right leg) squat jumps and calculated mechanical output per leg. We also used a model of the human musculoskeletal system to simulate two-leg and one-leg jumps, starting from the initial position observed in the subjects. The model had muscle stimulation as input, which was optimized using jump height as performance criterion. The model did not incorporate a reduced maximal neural drive in the two-leg jump. Both in the subjects and in the model, the work of the right leg was more than 20% less in the two-leg jump than in the one-leg jump. Peak electromyogram levels in the two-leg jump were reduced on average by 5%, but the reduction was only statistically significant in m. rectus femoris. In the model, approximately 75% of the bilateral deficit in work per leg was explained by higher shortening velocities in the two-leg jump, and the remainder was explained by lower active state of muscles. It was concluded that the bilateral deficit in jumping is primarily caused by the force-velocity relationship rather than by a reduction of neural drive.
Smad proteins have been identified as mediators of intracellular signal transduction by members of the transforming growth factor-β (TGF-β) superfamily, which affect cell proliferation, ...differentiation, as well as pattern formation during early vertebrate development. Following receptor activation, Smads are assembled into heteromeric complexes consisting of a pathway-restricted Smad and the common Smad4 that are subsequently translocated into the nucleus where they are thought to play an important role in gene transcription. Here we report the identification of Smad Binding Elements (SBEs) composed of the sequence CAGACA in the promoter of theJunB gene, an immediate early gene that is potently induced by TGF-β, activin, and bone morphogenetic protein (BMP) 2. TwoJunB SBEs are arranged as an inverted repeat that is transactivated in response to Smad3 and Smad4 co-overexpression and shows inducible binding of a Smad3- and Smad4-containing complex in nuclear extracts from TGF-β-treated cells. Bacterial-expressed Smad proteins bind directly to the SBE. Multimerization of the SBE creates a powerful TGF-β-inducible enhancer that is also responsive to activin and BMPs. The identification of the sequence CAGACA as a direct binding site for Smad proteins will facilitate the identification of regulatory elements in genes that are activated by members of the TGF-β superfamily.
In the present study we examined in more detail the dual role of the c-JUN N-terminal kinase (JNK) and p38 stress-activated protein kinase pathways in mediating apoptosis or cellular activation in ...hematopoietic cells. Growth factor deprivation of the erythroleukemic cell line TF-1 led to apoptosis which was associated with an enhanced activity of JNK and p38 and immediate dephosphorylation of the extracellular signal-regulated kinases (ERKs). Enhanced activity of p38 and JNK was not only observed during apoptosis but also in TF-1 cells stimulated with IL-1. IL-1 rescued TF-1 cells from apoptosis. In this case, the upregulation of p38 and JNK was associated with an enhanced activity of ERK. By using SB203580, a specific inhibitor of the p38 signaling pathway, it was demonstrated that p38 plays a pivotal role in the apoptotic process. SB203580 repressed the apoptotic process to a large extent. In contrast, PD98059, a specific inhibitor of the ERK pathway, counteracted the suppressive effects of SB203580 and IL-1 on the apoptotic process indicating that the protective effect of SB203580 and IL-1 might be the result of a shift in the balance between the ERK1/2 and p38/JNK route. This was also supported by experiments with TF-1 cells overexpressing the Shc protein that demonstrated a significantly lower percentage of apoptotic cells, which coincided with higher ERK activity. Finally, the IL-1 and SB203580-mediated effects were associated with an enhanced nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) binding activity, which could also be blocked by PD98059. These data demonstrate a dual function of the p38 pathway whereby other factors, such as ERK kinases, AP-1 and NF-kappaB, might determine the final cellular response.
The JunB gene is activated by many stimuli including transforming growth factor β (TGFβ) family members and interleukin-6 (IL-6). Here the effect of TGFβ activated kinase 1 (TAK1), a mitogen ...activated protein kinase kinase kinase (MAPKKK) implicated in TGFβ, bone morphogenetic protein (BMP) and interleukin-1 (IL-1) signaling, on JunB promoter activity was investigated. Promoter analysis led to the identification of a CCAAT motif in the JunB gene, essential for activation by TAK1. Transfer of this CCAAT element to a heterologous minimal promoter conferred TAK1-responsiveness. The CCAAT-binding transcription factor, nuclear factor Y (NF-Y), activated the JunB promoter and a dominant negative NF-YA construct inhibited TAK1 activation of JunB. Our results demonstrate that JunB gene activation by TAK1 is mediated by the CCAAT-binding factor NF-Y.
The need for deep groin dissection when superficial nodes contain metastatic melanoma is controversial.
A review of 362 therapeutic groin dissections performed at our tertiary referral center between ...1961 and 1995 revealed 71 patients (20%) with positive iliac and/or obturator nodes. This group was analyzed for survival rates, prognostic factors for survival, regional tumor control, and morbidity.
Patients with involved deep nodes exhibited overall 5-year and 10-year survival rates of 24% (SE, 5%) and 20% (SE, 5%), respectively. Independent prognostic factors for survival were the number of positive iliac nodes (P = .0011), the Breslow thickness (P = .0069), and the site of the primary tumor (P = .0075). Patients with an unknown primary tumor seemed to have better prognoses. Seven patients (10%) experienced recurrence in the surgically treated groin. The short- and long-term morbidity rates (infection, 17%; skin flap necrosis, 15%; seroma, 17%; mild/ moderate lymphedema, 19%; severe lymphedema, 6%) compared well with those of other series studying inguinal as well as ilioinguinal dissections.
From the present study it can be concluded that removal of deep lymph node metastases is worthwhile, because one of every five such patients survives for 10 years. Prognostic factors for survival are the number of involved iliac nodes, the Breslow thickness, and the site of the primary tumor. Long-term regional tumor control can be obtained for 90% of the patients. The morbidity of an additional deep lymph node dissection is acceptable.
A selection of melanoma patients with groin metastases can benefit from a pelvic (iliac/obturator) lymph node dissection in addition to the infrainguinal dissection. However, there are no reliable ...criteria to determine which patients may benefit from such an inguinal-pelvic lymphadenectomy.
In 142 patients (group A) out of a review of 214 groin dissections performed between 1980 and 1994, the tumor status of Cloquet's node was traced retrospectively. In 52 additional patients (group B), the status of Cloquet's node was registered prospectively. The number of positive lymph nodes and the total numbers of retrieved nodes were recorded as well. All patients underwent a combined therapeutic inguinal-pelvic lymph node dissection between January 1995 and June 1999 in a tertiary referral center.
Cloquet's node was free of disease in 18 of 39 patients with involved pelvic nodes in the retrospective study (sensitivity, 54%; negative predictive value, 83%). In the prospective study, 9 of the 20 patients with involved pelvic nodes had a tumor-free Cloquet's node (sensitivity, 55%; negative predictive value, 78%). Additional immunohistochemical staining of Cloquet's node resulted in a sensitivity of 65%. In the combined group A&B, the number of positive nodes in the inguinal region (cutoff point more than three nodes) had a sensitivity of 41% and a negative predictive value of 78% to determine the pelvic nodal status. When we combined the number of positive inguinal nodes and Cloquet's node in group A&B, the best sensitivity was 56% and the best negative predictive value was 82%.
Cloquet's node has a low sensitivity to predict the pelvic nodal tumor status. This was barely improved when we accounted for the number of positive inguinal nodes. Groin lymph node dissections should encompass the iliac and obturator compartments in patients with palpable inguinal node metastases.
The vitamin A derivative retinoic acid (RA) is involved in vertebrate anteroposterior axis formation and cellular differentiation and has been shown to modulate the expression of a number of genes ...implicated in the control of early embryonal development. Under defined culture conditions, all-trans-RA induces differentiation of P19 embryonal carcinoma cells into neural derivatives. In this report, we describe the isolation and partial characterization of 14 RA-regulated genes from P19 cells committed to differentiate along the neural pathway. In addition to the previously recognized genes encoding vimentin, heat stable antigen, neural cadherin, Hox-B2, F52/MacMARCKS, thymosin beta 4b, and the murine homolog of COUP-TF1, we identified 7 novel genes, 5 of which are predominantly expressed in developing neural tissues as shown by in situ hybridization. The results confirm the usefulness of the P19 system in the isolation and study of the regulation of developmentally expressed genes.
Abstract
Introduction
Ageing is the major risk factor for cardiovascular disease. Long non-coding RNAs are emerging as novel regulators of cellular functions and contributors to cardiovascular ...ageing. One of the hallmarks of aging is telomere attrition. Non-coding transcripts called Telomeric repeat-containing RNA (TERRA) are molecules of 0.2–10kb in length which are transcribed from the subtelomeres and telomeres of chromosomes and might play a role in cardiovascular ageing.
Purpose
This study aims to characterize the role of TERRA in aging of the cardiovascular system.
Methods and results
TERRA molecules from different chromosomes were upregulated in the hearts of old mice compared to young mice (p=0.002). Increased TERRA expression was also shown in heart tissue of patients with ischemic heart disease compared to donors (p=0.001). In vitro an upregulation of the TERRA molecule transcribed from chromosome 20 (h20q-TERRA) was found with increasing passage in human umbilical vein endothelial cells (HUVECs) (p=0.014) and IPSC-derived cardiomyocytes (p=0.011). After h20q-TERRA knockdown with LNA GapmeRs, HUVECs show less sprout formation in a spheroid assay compared to negative control transfected HUVECs (p=0.002), without showing a change in migration (p=0.205) or proliferation (p=0.114). H20q-TERRA knockdown revealed an increase in apoptosis (p=0.015) and telomeric DNA damage (p=0.011) and a decrease in telomere length (p<0.001), while lentiviral TERRA-repeat overexpression had the opposite effect (p=0.016, p=0.031, p<0.001, resp.). Apoptosis (p=0.012) and telomeric DNA damage (p=0.007) were also increased after the knockdown of h20q-TERRA in human cardiomyocytes. An apoptosis pathway profiler array in HUVECs showed that the expression of the antioxidant PON2 was decreased after knockdown of h20q-TERRA (p=0.040). PON2 expression was increased after TERRA overexpression (p=0.003). RNA immunoprecipitation revealed that TERRA can bind to PON2. Silencing PON2 in TERRA overexpressing cells diminished the TERRA-mediated decrease in caspase activation, suggesting a detrimental role for PON2 in caspase activation and endothelial cell survival.
Conclusion
Our data demonstrates that TERRA is upregulated with ageing and plays a role in endothelial and cardiomyocyte function and survival.
Funding Acknowledgement
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020
Background
Anastomotic leakage is a potential major complication after colorectal surgery. The C‐seal was developed to help reduce the clinical leakage rate. It is an intraluminal sheath that is ...stapled proximal to a colorectal anastomosis, covering it intraluminally and thus preventing intestinal leakage in case of anastomotic dehiscence. The C‐seal trial was initiated to evaluate the efficacy of the C‐seal in reducing anastomotic leakage in stapled colorectal anastomoses.
Methods
This RCT was performed in 41 hospitals in the Netherlands, Germany, France, Hungary and Spain. Patients undergoing elective surgery with a stapled colorectal anastomosis less than 15 cm from the anal verge were eligible. Included patients were randomized to the C‐seal and control groups, stratified for centre, anastomotic height and intention to create a defunctioning stoma. Primary outcome was anastomotic leakage requiring invasive treatment.
Results
Between December 2011 and December 2013, 402 patients were included in the trial, 202 in the C‐seal group and 200 in the control group. Anastomotic leakage was diagnosed in 31 patients (7·7 per cent), with a 10·4 per cent leak rate in the C‐seal group and 5·0 per cent in the control group (P = 0·060). Male sex showed a trend towards a higher leak rate (P = 0·055). Construction of a defunctioning stoma led to a lower leakage rate, although this was not significant (P = 0·095).
Conclusion
C‐seal application in stapled colorectal anastomoses does not reduce anastomotic leakage. Registration number: NTR3080 (http://www.trialregister.nl/trialreg/index.asp).
Not effective
Ductal carcinoma in situ (DCIS) can progress to invasive breast cancer (IBC), but often never will. As we cannot predict accurately which DCIS-lesions will or will not progress to IBC, almost all ...women with DCIS undergo breast-conserving surgery supplemented with radiotherapy, or even mastectomy. In some countries, endocrine treatment is prescribed as well. This implies many women with non-progressive DCIS undergo overtreatment. To reduce this, the LORD patient preference trial (LORD-PPT) tests whether mammographic active surveillance (AS) is safe by giving women with low-risk DCIS a choice between treatment and AS. For this, sufficient knowledge about DCIS is crucial. Therefore, we assessed women's DCIS knowledge in association with socio-demographic and clinical characteristics.
LORD-PPT participants (N = 376) completed a questionnaire assessing socio-demographic and clinical characteristics, risk perception, treatment choice and DCIS knowledge after being informed about their diagnosis and treatment options.
66 % of participants had poor knowledge (i.e., answered ≤3 out of 7 knowledge items correctly). Most incorrect answers involved overestimating the safety of AS and misunderstanding of DCIS prognostic risks. Overall, women with higher DCIS knowledge score perceived their risk of developing IBC as being somewhat higher than women with poorer knowledge (p = 0.049). Women with better DCIS knowledge more often chose surgery whilst most women with poorer knowledge chose active surveillance (p = 0.049).
Our findings show that there is room for improvement of information provision to patients. Decision support tools for patients and clinicians could help to stimulate effective shared decision-making about DCIS management.
•Low-risk DCIS is surgically treated, but not all will progress to breast cancer.•LORD trial: women can opt for conventional treatment or for active surveillance.•Adequate knowledge about DCIS is essential for patients to make an informed choice.•Overall DCIS knowledge about safety of active surveillance was poor.•DCIS knowledge level is associated with risk perception and treatment choice.
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