Long-term health sequelae and quality of life at least 6 months after infection with SARS-CoV-2: design and rationale of the COVIDOM-study as part of the NAPKON population-based cohort platform (POP).

PURPOSE: Over the course of COVID-19 pandemic, evidence has accumulated that SARS-CoV-2 infections may affect multiple organs and have serious clinical sequelae, but on-site clinical examinations with non-hospitalized samples are rare. We, therefore, aimed to systematically assess the long-term health status of samples of hospitalized and non-hospitalized SARS-CoV-2 infected individuals from three regions in Germany. METHODS: The present paper describes the COVIDOM-study within the population-based cohort platform (POP) which has been established under the auspices of the NAPKON infrastructure (German National Pandemic Cohort Network) of the national Network University Medicine (NUM). Comprehensive health assessments among SARS-CoV-2 infected individuals are conducted at least 6 months after the acute infection at the study sites Kiel, Würzburg and Berlin. Potential participants were identified and contacted via the local public health authorities, irrespective of the severity of the initial infection. A harmonized examination protocol has been implemented, consisting of detailed assessments of medical history, physical examinations, and the collection of multiple biosamples (e.g., serum, plasma, saliva, urine) for future analyses. In addition, patient-reported perception of the impact of local pandemic-related measures and infection on quality-of-life are obtained. RESULTS: As of July 2021, in total 6813 individuals infected in 2020 have been invited into the COVIDOM-study. Of these, about 36% wished to participate and 1295 have already been examined at least once. CONCLUSION: NAPKON-POP COVIDOM-study complements other Long COVID studies assessing the long-term consequences of an infection with SARS-CoV-2 by providing detailed health data of population-based samples, including individuals with various degrees of disease severity. TRIAL REGISTRATION: Registered at the German registry for clinical studies (DRKS00023742).

[Ventilation Patients between Acute Care and Long-term Out-of-Hospital Ventilation - Routine Documentation based Analysis of the Care Situation]. / Beatmungspatienten zwischen Akutversorgung und außerstationärer Langzeitbeatmung.

BACKGROUND: The number of invasive and non-invasive long-term out-of-hospital ventilations has been increasing rapidly for years. At the same time, there is poor information on the quality of care of out-of-hospital ventilated patients. The present investigation was conducted as part of the OVER-BEAS study. The aim of this study was to describe the care situation of weaning patients from admission to discharge from the weaning center using existing routine documentation. MATERIAL AND METHODS: In our retrospective analysis, we included all patients admitted in 2018 via the weaning ward of the Thorax Center Münnerstadt. Descriptive analysis of routine data collected as part of quality management was performed. Data sources were the WeanNet database, the discharge letter of the weaning center, and the transfer report of the referring hospital. RESULTS: In the studied weaning center, 50.8 % of the patients (n = 31) could be completely weaned from the respirator and extubated or decannulated (category 3aI). If complete weaning was not successful, 75.0 % (n = 21) required the constant presence of specially trained staff or a specialist nurse in the further course. In this case, further care was mostly provided in inpatient care facilities (e. g., ventilator shared living community). CONCLUSION: Based on routine documentation, the care situation of weaning patients can be presented and compared with known data. In this way, the outcome quality of a weaning center can be made comparable.

[Ventilation Patients between Acute Care and Long-term Out-of-Hospital Ventilation - Routine Documentation based Analysis of the Care Situation]. / Beatmungspatienten zwischen Akutversorgung und außerstationärer Langzeitbeatmung.

BACKGROUND: The number of invasive and non-invasive long-term out-of-hospital ventilations has been increasing rapidly for years. At the same time, there is poor information on the quality of care of out-of-hospital ventilated patients. The present investigation was conducted as part of the OVER-BEAS study. The aim of this study was to describe the care situation of weaning patients from admission to discharge from the weaning center using existing routine documentation. MATERIAL AND METHODS: In our retrospective analysis, we included all patients admitted in 2018 via the weaning ward of the Thorax Center Münnerstadt. Descriptive analysis of routine data collected as part of quality management was performed. Data sources were the WeanNet database, the discharge letter of the weaning center, and the transfer report of the referring hospital. RESULTS: In the studied weaning center, 50.8 % of the patients (n = 31) could be completely weaned from the respirator and extubated or decannulated (category 3aI). If complete weaning was not successful, 75.0 % (n = 21) required the constant presence of specially trained staff or a specialist nurse in the further course. In this case, further care was mostly provided in inpatient care facilities (e. g., ventilator shared living community). CONCLUSION: Based on routine documentation, the care situation of weaning patients can be presented and compared with known data. In this way, the outcome quality of a weaning center can be made comparable.

The Effects of Colored Pigments on the Translucency of Experimental Dental Resin Composites.

OBJECTIVE: Colored pigments are incorporated into dental resin composites to produce clinically acceptable shades for restorative materials but studies on their effects on translucency are rare. The aim of this study was to examine the effects of the addition of different colored pigments on the translucency of experimental dental resin composites. MATERIALS AND METHODS: 12 types of experimental dental resin composites containing different concentrations of red and yellow iron oxide pigments were formulated and light-cured. Total and diffuse translucency as well as CIE L*a*b* values were measured and the color differences were calculated. RESULTS: There was a statistically significant difference in the translucency values between the composites with no pigments and the composites with increasing concentrations of the pigments (p<0.05). The translucency decreased as the concentration of the pigments increased. However at pigment concentrations greater than 0.02%, the translucency of the composites reached a plateau and ceased to be influenced by the addition of the pigments (p⟨0.05). All color differences were in the range of 3.62-16.00 ΔE*ab unit. CONCLUSIONS: The pigments used in this study can influence the translucency of the experimental resin composites and should be considered as an important factor by clinicians to achieve optimal esthetic restorative outcome.

Microbleeds in ischemic vs hemorrhagic strokes on novel oral anticoagulants.

OBJECTIVES: To identify differences in clinical characteristics and severity of cerebral small vessel disease (CSVD) including cerebral microbleeds (CMBs), between patients suffering ischemic stroke (IS) or intracerebral hemorrhage (ICH) while taking novel (non-vitamin K antagonists) oral anticoagulants (NOACs). METHODS: Multicenter, prospective, observational cohort study performed at 38 centers between 2012 and 2015. We compared demographics, comorbidity, and functional status (before and after stroke) between NOAC-IS and NOAC-ICH patients. Extent of white matter lesions (WML), and location and counts of CMBs were analyzed in a subgroup of patients for whom MRI including hemorrhage-sensitive sequences was available. RESULTS: A total of 351 patients were included (290 NOAC-IS, 61 NOAC-ICH). Functional status was worse in NOAC-ICH patients before and after stroke. No significant differences were found for demographic variables and cardiovascular comorbidity. In the subgroup with available MRI (n = 116), the proportion of patients with at least one CMB was higher in NOAC-ICH than in NOAC-IS (15/19 [79%] vs 36/97 [37%], P < .001), as was the absolute number of CMBs (median 5 [IQR 1-24] vs 0 [0-1], P < .001). WML were more extensive in NOAC-ICH than in NOAC-IS patients. Adjusted for WML, logistic regression analysis showed higher odds of NOAC-ICH in patients with CMB than without (OR 5.60 [1.64-19.14], P = .006). CONCLUSIONS: Patients with NOAC-ICH have similar clinical characteristics but a higher prevalent burden of CSVD compared to NOAC-IS. The role of neuroimaging in selection of patients for anticoagulation with NOAC requires further investigation in longitudinal studies.

Predicting Clinical Outcome After Surgical Treatment in Patients With Carpal Tunnel Syndrome.

PURPOSE: Carpal tunnel release (CTR) is typically offered to symptomatic patients with electrophysiological abnormalities when night orthoses no longer prevent waking with numbness and preferably before there is any static numbness, weakness, or atrophy. The ability to predict the amount of symptom relief after CTR could be beneficial for managing patient expectations and, therefore, improve treatment satisfaction. Therefore, the aim of this study was to identify predictors for symptom relief after CTR and to determine their contribution to symptom relief at 6 months after surgery. METHODS: A total of 1,049 patients who underwent CTR between 2011 and 2015 at 1 of 11 Xpert Clinics in the Netherlands were asked to complete online questionnaires at intake and 3 and 6 months after surgery. Patient demographics, comorbidities, and baseline scores were considered potential predictors for the amount of symptom relief on the Boston Carpal Tunnel Questionnaire (BCTQ) score, which was the primary outcome measure. RESULTS: A low score on the BCTQ at intake, a codiagnosis of a trigger finger, ulnar nerve neuropathy, trapeziometacarpal joint arthrosis, and instability or arthrosis of the wrist were associated with a smaller improvement in the BCTQ domains after a CTR at 6 months after surgery and accounted for 35% to 42% of the variance on the BCTQ domains in our multivariable regression models. CONCLUSIONS: In this study, we showed that clinical severity of carpal tunnel syndrome at intake is the most important factor in estimating symptom relief after surgical treatment. Furthermore, this study contributes to a more precise understanding of the capabilities of CTR in relieving symptoms for different subgroups of patients. Results of our study can be used to manage patient expectation on symptom relief from CTR. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

The effects of diet-induced obesity on B cell function.

B-1 and B-2 B cell subsets carry out a diverse array of functions that range broadly from responding to innate stimuli, antigen presentation, cytokine secretion and antibody production. In this review, we first cover the functional roles of the major murine B cell subsets. We then highlight emerging evidence, primarily in preclinical rodent studies, to show that select B cell subsets are a therapeutic target in obesity and its associated co-morbidities. High fat diets promote accumulation of select murine B cell phenotypes in visceral adipose tissue. As a consequence, B cells exacerbate inflammation and thereby insulin sensitivity through the production of autoantibodies and via cross-talk with select adipose resident macrophages, CD4(+) and CD8(+) T cells. In contrast, interleukin (IL)-10-secreting regulatory B cells counteract the proinflammatory profile and improve glucose sensitivity. We subsequently review data from rodent studies that show pharmacological supplementation of obesogenic diets with long chain n-3 polyunsaturated fatty acids or specialized pro-resolving lipid mediators synthesized from endogenous n-3 polyunsaturated fatty acids boost B cell activation and antibody production. This may have potential benefits for improving inflammation in addition to combating the increased risk of viral infection that is an associated complication of obesity and type II diabetes. Finally, we propose potential underlying mechanisms throughout the review by which B cell activity could be differentially regulated in response to high fat diets.

Chondro/osteoblastic and cardiovascular gene modulation in human artery smooth muscle cells that calcify in the presence of phosphate and calcitriol or paricalcitol.

Vitamin D sterol administration, a traditional treatment for secondary hyperparathyroidism, may increase serum calcium and phosphorus, and has been associated with increased vascular calcification (VC). In vitro studies suggest that in the presence of uremic concentrations of phosphorus, vitamin D sterols regulate gene expression associated with trans-differentiation of smooth muscle cells (SMCs) to a chondro/osteoblastic cell type. This study examined effects of vitamin D sterols on gene expression profiles associated with phosphate-enhanced human coronary artery SMC (CASMC) calcification. Cultured CASMCs were exposed to phosphate-containing differentiation medium (DM) with and without calcitriol, paricalcitol, or the calcimimetic R-568 (10(-11)-10(-7) M) for 7 days. Calcification of CASMCs, determined using colorimetry following acid extraction, was dose dependently increased (1.6- to 1.9-fold) by vitamin D sterols + DM. In contrast, R-568 did not increase calcification. Microarray analysis demonstrated that, compared with DM, calcitriol (10(-8) M) + DM or paricalcitol (10(-8) M) + DM similarly and significantly (P < 0.05) regulated genes of various pathways including: metabolism, CYP24A1; mineralization, ENPP1; apoptosis, GIP3; osteo/chondrogenesis, OPG, TGFB2, Dkk1, BMP4, BMP6; cardiovascular, HGF, DSP1, TNC; cell cycle, MAPK13; and ion channels, SLC22A3 KCNK3. R-568 had no effect on CASMC gene expression. Thus, SMC calcification observed in response to vitamin D sterol + DM may be partially mediated through targeting mineralization, apoptotic, osteo/chondrocytic, and cardiovascular pathway genes, although some gene changes may protect against calcification. Further studies to determine precise roles of these genes in development of, or protection against VC and cardiovascular disease are required.

Evaluation of pulsed electric fields technology for the improvement of subsequent carotenoid extraction from dried Rhodotorula glutinis yeast.

This research aims to evaluate whether the electroporation of Rhodotorula glutinis fresh biomass improved the subsequent extraction of carotenoids from dry biomass using supercritical CO2 and traditional solvent extraction. Supercritical CO2 extraction yields were low after all treatments assayed. Similarly, solvent extraction of carotenoids from untreated or PEF treated cells that were immediately freeze-dried after the pre-treatment was neither effective (extraction yield < 20% total content). Conversely, PEF-treatment and subsequent intermediate incubation in aqueous buffer for 24 h, followed by freeze-drying and extraction, led to a large improvement with the three solvents assayed (acetone, hexane, ethanol). Ethanol was the most efficient, reaching an extraction yield of 80% of total carotenoid, which represents a recovery of 267 µg/gdw. Torularhodin esters constituted the main carotenoid found in the extracts. This is of great interest, as ethanol is eco-friendly solvent and potential applications of torularhodin range from food to medical purposes.

Visual field defects after selective amygdalohippocampectomy and standard temporal lobectomy.

BACKGROUND: Selective amygdalohippocampectomy (SelAH) is increasingly performed in patients with mesial temporal lobe epilepsy and hippocampal sclerosis. To determine whether visual field defects are less pronounced after SelAH than after standard temporal lobectomy (StTL), we retrospectively analyzed postoperative quantitative visual fields after the 2 procedures. METHODS: Humphrey visual field analysis was obtained postoperatively in 18 patients who had undergone SelAH and in 33 patients who had undergone StTL. The SelAH was performed via a transcortical approach through the middle temporal gyrus and included the amygdala, 3 cm of the hippocampus, and the parahippocampal gyrus. The visual field pattern deviation was used for analysis. We considered a defect clinically significant if there were 3 contiguous coordinates affected at the 5% level or 2 at the 1% level. RESULTS: All but 2 of 18 patients who had undergone SelAH had homonymous superior quadrantic visual field defects contralateral to the side of the surgery. One patient had no defects by our criteria, and one had a mild defect that reached significance only in the ipsilateral eye. The averaged defect affected mostly coordinates close to the vertical meridian with relative sparing of points close to the horizontal meridian. All but 3 of the 33 patients who had undergone StTL had homonymous superior quadrantic visual field defects. One patient had no defects; 2 had defects that reached significance in only one eye. The averaged defect involved all points in the affected quadrant, but was also greater near the vertical meridian. Of 13 tested visual field coordinates, 4 were significantly less affected by SelAH in the ipsilateral eye and 3 in the contralateral eye. The coordinates close to the horizontal meridian were significantly spared by SelAH. CONCLUSIONS: Visual field defects are very common after SelAH but are significantly less pronounced than after StTL. In particular, the visual field close to the horizontal meridian is relatively spared in SelAH.

Single-cell electroporation for gene transfer in vivo.

We report an electroporation technique for targeting gene transfer to individual cells in intact tissue. Electrical stimulation through a micropipette filled with DNA or other macromolecules electroporates a single cell at the tip of the micropipette. Electroporation of a plasmid encoding enhanced green fluorescent protein (GFP) into the brain of intact Xenopus tadpoles or rat hippocampal slices resulted in GFP expression in single neurons and glia. In vivo imaging showed morphologies, dendritic arbor dynamics, and growth rates characteristic of healthy cells. Coelectroporation of two plasmids resulted in expression of both proteins, while electroporation of fluorescent dextrans allowed direct visualization of transfer of molecules into cells. This technique will allow unprecedented spatial and temporal control over gene delivery and protein expression.

Postsynaptic CPG15 promotes synaptic maturation and presynaptic axon arbor elaboration in vivo.

The formation of CNS circuits is characterized by the coordinated development of neuronal structure and synaptic function. The activity-regulated candidate plasticity gene 15 (cpg15) encodes a glycosylphosphatidylinositol (GPI)-linked protein whose in vivo expression increases the dendritic arbor growth rate of Xenopus optic tectal cells. We now demonstrate that tectal cell expression of CPG15 significantly increases the elaboration of presynaptic retinal axons by decreasing rates of branch retractions. Whole-cell recordings from optic tectal neurons indicate that CPG15 expression promotes retinotectal synapse maturation by recruiting functional AMPA receptors to synapses. Expression of truncated CPG15, lacking its GPI anchor, does not promote axon arbor growth and blocks synaptic maturation. These results suggest that CPG15 coordinately increases the growth of pre- and postsynaptic structures and the number and strength of their synaptic contacts.

The scaffold protein, Homer1b/c, regulates axon pathfinding in the central nervous system in vivo.

Homer proteins are a family of multidomain cytosolic proteins that have been postulated to serve as scaffold proteins that affect responses to extracellular signals by regulating protein-protein interactions. We tested whether Homer proteins are involved in axon pathfinding in vivo, by expressing both wild-type and mutant isoforms of Homer in Xenopus optic tectal neurons. Time-lapse imaging demonstrated that interfering with the ability of endogenous Homer to form protein-protein interactions resulted in axon pathfinding errors at stereotypical choice points. These data demonstrate a function for scaffold proteins such as Homer in axon guidance. Homer may facilitate signal transduction from cell-surface receptors to intracellular proteins that govern the establishment of axon trajectories.

[Intravitreal injection of bevacizumab for exsudative AMD with occult or minimal classic choroidal neovascularisation (CNV)]. / Bevacizumab intravitreal zur Behandlung okkulter und minimal klassischer choroidaler Neovaskularisation (CNV) bei AMD.

PURPOSE: Systemic anti-VEGF therapy with bevacizumab was effective in neovascular AMD in the SANA study. Intravitreal bevacizumab has the advantage that a high concentration can be achieved in the eye with a low dose. First clinical studies showed a good therapeutic effect. METHODS: In a clinical study 93 patients with occult or minimal classic CNV due to neovascular AMD were treated with intravitreal injections of Bevacizumab (1.25 mg). Before, 1, 3 and 6 months after treatment visual acuity, intraocular pressure measurement, angiography and OCT examination were performed. After one day and after one week an eye examination was done and the intraocular pressure was measured. RESULTS: Bevacizumab was well tolerated and we had no complications. Mean visual acuity was 20 / 80 at baseline. Visual acuity was stabilised but not significantly improved after 1, 3 and 6 months (20 / 80). 70 (75 %) patients showed reduced leakage in fluorescein angiography after 6 month. In OCT retinal thickness was reduced significantly after 1, 3 and 6 months (OCT: mean 323 microm at baseline, 260 microm after 1, 290 microm after 3 and 275 microm after 6 months). CONCLUSIONS: Intravitreal therapy with bevacizumab was safe and well tolerated. It is a therapeutic option in treating occult choroidal neovascularisations and minimal classic CNV. Six months after intravitreal administration of bevacizumab mean visual acuity was stabilised. Retinal thickness and leakage were more reduced after 1 month than after 3 and 6 months. According to our results, a monthly injection schedule could give more favourable results.

[Photodynamic therapy with verteporfin combined with intravitreal injection of bevacizumab for occult and classic CNV in AMD]. / Photodynamische Therapie kombiniert mit intravitrealer Injektion von Bevacizumab zur Behandlung okkulter und klassischer choroidaler Neovaskularisationen bei AMD.

PURPOSE: The aim of this study is to discuss the effect and outcome of a combined photodynamic therapy and intravitreal injection of bevacizumab (1.25 mg) in occult and classic choroidal neovascularisation (CNV) due to AMD. Especially cases of occult CNV with pigment epithelium detachment (PED) are not likely to respond positively to standard photodynamic therapy, often ending up in PED enlargement or tearing of the RPE. METHODS: In a pilot study involving 23 patients, intravitreal injections of bevacizumab were administered within 12 to 24 hours after standard PDT to reduce the post-PDT increase of proangiogenic and inflammatory factors. Before and at 1, 3 and 6 month after treatment visual acuity and OCT examinations (retinal thickness) were performed. RESULTS: Mean visual acuity was significantly improved compared to baseline. (VA baseline 20/125, after 1 month 20/80, after 3 months 20/80, and 20/80 after 6 months) and an enlargement of the PED in occult CNV was prevented. We found no RPE rip. OCT findings in patients with occult and classic choroidal neovascularisation 1, 3 and 6 months after combination therapy showed a reduced retinal thickness compared to baseline. CONCLUSIONS: Photodynamic therapy combined with injection of intravitreal bevacizumab tends to be more effective compared to PDT monotherapy by reducing the post-PDT increase of vascular growth and inflammatory factors. Our short-term results are very promising. Further studies are necessary to show the long-term effect of PDT and anti-VEGF combination therapy.

Risk-adjusted procedure tailoring leads to uniformly low complication rates in ventral and incisional hernia repair: a propensity score analysis and internal validation of classification criteria.

BACKGROUND: The usual approach in hernia surgery is to select the ideal repair method independent of the patient's characteristics. In the present study, we change the approach to ask which technique is best for the individual patient`s risk profile. For this, two criteria are important: does the patient need reconstruction of the abdominal wall? or does he or she need treatment of symptoms without being exposed to unnecessarily high perioperative risks? METHODS: In a heuristic selection procedure, 486 consecutive patients were classified according to their characteristics as low-risk or high-risk for postoperative complications. Low-risk patients preferentially underwent open abdominal wall reconstruction with mesh (MFR + mesh), high-risk patients mainly a bridging-mesh procedure, either by laparoscopic (Lap.-IPOM) or open approach (Open-IPOM). Primary outcome was the incidence of postoperative complications. Secondary outcome was the recurrence-free interval. The propensity score was used for covariate adjustment analyzing recurrence rate as well as postoperative complications using Cox regression and logistic regression, respectively. RESULTS: Comparison of all surgical procedures showed risk factors had no independent influence on occurrence of complications (p = 0.110). Hernial gap width was an independent factor for occurrence of complications (p = 0.002). Propensity score adjustment revealed Lap.-IPOM to have a significantly higher recurrence rate than MFR + mesh (HR 2.367, 95% CI 1.123-4.957, p = 0.024). Three or more risk factors were protective against recurrence (HR 0.454, 95% CI 0.221-0.924, p = 0.030). In the univariate Cox regression analysis for recurrence, age >50 years was a protective prognostic factor (HR 0.412, 95% CI 0.245-0.702, p = 0.002). CONCLUSIONS: The classification criteria applied were internally validated. The heuristic algorithm ensured that patients at high-risk of complications did not have a higher perioperative complication rate than patients at low-risk.

Comparison of equilibration times when freezing epididymal sperm from African buffalo (Syncerus caffer) using Triladyl or AndroMed.

Because of risks of disease transmission, it is not possible to move African buffalo (Syncerus caffer) within South Africa. Therefore, new ways must be found to enable exchange of genetic material and to increase genetic diversity. In this study epididymal sperm from 11 African buffaloes was exposed to 8 different pre-freezing equilibration times, using 2 different semen extenders. To test the influence of equilibration time and to find a practical way of freezing sperm in the field equilibration times between 2 and 9 h were compared. The extenders used were Triladyl and the totally defined extender AndroMed (both Minitüb, Tiefenbach, Germany). Post-thaw motility, longevity and acrosomal integrity were compared. Different equilibration times did not result in different post-thaw qualities. The use of Triladyl resulted almost always in higher post-thaw motilities and in better acrosomal integrity. Individual bulls had a significant influence on measured parameters. Results indicate that sperm flushed in the field can be stored in freezing medium for up to 9 h before being further processed and that Triladyl is superior to AndroMed when freezing epididymal African buffalo sperm. This knowledge is important to plan fieldwork, since working conditions are usually far from the ideal of a laboratory.

Efficacy and safety of deferasirox in non-thalassemic patients with elevated ferritin levels after allogeneic hematopoietic stem cell transplantation.

Elevated serum ferritin contributes to treatment-related morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). The multicenter DE02 trial assessed the safety, efficacy and impact of deferasirox on iron homeostasis after allogeneic HSCT. Deferasirox was administered at a starting dose of 10 mg/kg per day to 76 recipients of allogeneic HSCT, with subsequent dose adjustments based on efficacy and safety. Deferasirox was initiated at a median of 168 days after HSCT, with 84% of patients still on immunosuppression. Baseline serum ferritin declined from 2045 to 957 ng/mL. Deferasirox induced a negative iron balance in 84% of patients. Hemoglobin increased in the first 3 months, and trough serum cyclosporine levels were stable. Median exposure was 330 days, with a median compliance rate of >80%. The most common investigator-reported drug-related adverse events (AEs) were increased blood creatinine (26.5%), nausea (9.0%) and abdominal discomfort (8.3%). Fifty-four (71.1%) patients experienced drug-related AEs, which occasionally resulted in discontinuation (gastrointestinal (n=6), skin (n=3), elevated transaminases (n=1) and creatinine (n=1)). The incidence of AEs appeared to be dose related, with 7.5 mg/kg per day being the best-tolerated dose. Low-dose deferasirox is an effective chelation therapy after allogeneic HSCT, with a manageable safety profile, even in patients receiving cyclosporine.

Mutual requirement of CDK4 and Myc in malignant transformation: evidence for cyclin D1/CDK4 and p16INK4A as upstream regulators of Myc.

We demonstrate in this paper that CDK4 which is a G1 phase specific cell cycle regulator and catalytic subunit of D-type cyclins has oncogenic activity similar to D-type cyclins themselves and is able to provoke focus formation when cotransfected with activated Ha-ras into primary rat embryo fibroblasts. Surprisingly, using two different mutants we show that CDK4's ability to bind to p16INK4a and not its kinase activity is important for its transforming potential. In addition, p16INK4a but not a mutant form that is found in human tumours can completely abrogate focus formation by CDK4 suggesting that CDK4 can malignantly transform cells by sequestering p16INK4a or other CKIs. We demonstrate that both cyclin D1 and CDK4 functionally depend on active Myc to exert their potential as oncogenes and vice versa that the transforming ability of Myc requires functional cyclin D/CDK complexes. Moreover, we find that p16INK4a and the Rb related protein p107 which releases Myc after phosphorylation by cyclin D1/CDK4 efficiently block Myc's activity as a transcriptional transactivator and as an oncogene. We conclude that both p16INK4a and cyclin D/CDK4 complexes are upstream regulators of Myc and directly govern Myc function in transcriptional transactivation and transformation via the pocket protein p107.

Malignant transformation by cyclin E and Ha-Ras correlates with lower sensitivity towards induction of cell death but requires functional Myc and CDK4.

We demonstrate in this paper that the G1 phase specific cell cycle regulator cyclin E is able to provoke focus formation when cotransfected with activated Ha-ras into primary rat embryo fibroblasts (REFs). Cyclin E/Ha-ras transformed cells are highly tumorigenic in synergeneic rats, are able to form colonies in soft agar and show protection towards apoptosis upon serum starvation or DNA damage compared to cells transformed by the combination of Myc, cyclin D1 or SV40 large T-antigen and Ha-ras. Lines that were established after cyclin E/Ha-ras or cyclin D1/Ha-ras transformation contain a large percentage of polyploid cells. This was not observed in cells transformed with other oncoproteins and Ha-ras pointing to an involvement of D- and E type cyclins in genomic instability. The cyclin dependent kinase inhibitors p21 and p27 but also p16 completely abrogate focus formation by cyclin E and Ha-ras suggesting that the oncogenic activity of cyclin E still requires functional G1 specific cyclin/CDK complexes. Moreover, inhibition of Myc function also blocks the oncogenic activity of cyclin E indicating a requirement of Myc for cyclin E function. The findings presented here demonstrate that cyclin E can act as an oncoprotein with a potential involvement in genomic instability and the prevention of cell death. Our data also present more evidence for a strict functional interdependency between G1 cyclin/CDK complexes and c-Myc.