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Background: This study examines the rheological properties of various dermal fillers, including hyaluronic acid (HA) fillers, poly-L-lactic acid (PLLA), and calcium hydroxylapatite-carboxymethylcellulose (CaHA-CMC) gels, with a particular focus on the impact of aqueous dilution on CaHA-CMC's rheology and potential clinical implications., Methods: Using standardized rheological analysis, we measured and compared the elastic modulus (G'), viscous modulus (G″), and the tan δ values of different dilutions of CaHA-CMC against published values of HA and PLLA fillers. The study aimed to determine the potential clinical use of application-specific CaHA-CMC hydrogel dilutions along a range of gel strength and cohesion for hydrogel fillers in current use., Results: The findings demonstrate that CaHA-CMC's rheological properties can be tailored across a broad spectrum of viscoelastic parameters through titrated dilution, ranging from high elasticity to low cohesion. Varying the aqueous volume allows for the rheomodulation of CaHA-CMC, potentially matching the entire rheological spectrum of HA fillers and suggesting an expanded range of clinical applications., Conclusions: The versatility of CaHA-CMC through dilution may offer a customizable approach for clinical applications, providing practitioners with the ability to fine-tune the properties of fillers to meet specific patient needs and treatment goals. This study lays the groundwork for the potential future use of filler dilutional rheomodulation in clinical practice, tailored to patient- and application-specific needs., Competing Interests: Drs. McCarthy, Radia El-Banna, and Nadine Hagedorn are employed by Merz Aesthetics. Dr. Soares is a paid speaker and trainer for Revance Therapeutics, Inc. and has received research grant funding from Merz Aesthetics. Dr. Chandawarkar is a paid clinical consultant and shareholder for Cypris Medical and Allergan Aesthetics, an Abbvie Company and has received travel support from Merz Aesthetics. Dr. Faria has received research grant funding and is a paid speaker and trainer for Merz Aesthetics., (Copyright © 2024 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.)

Objectives: To evaluate the diagnostic performance of platelet function analyzer (PFA) and The International Society on Thrombosis and Hemostasis bleeding-assessment-tool (ISTH-BAT) in detecting mild inherited platelet function disorders (IPFDs) in children with suspected bleeding disorders., Methods: Prospective single-center diagnostic study including consecutive patients <18 years with suspected bleeding disorder and performing a standardized workup for platelet function defects including ISTH-BAT, PFA, platelet aggregation testing, blood smear-based immunofluorescence, and next-generation sequencing-based genetic screening for IPFDs., Results: We studied 97 patients, of which 34 von Willebrand disease (VWD, 22 type-1, 11 type-2), 29 IPFDs (including delta-/alpha-storage pool disease, Glanzmann thrombasthenia, Hermansky-Pudlak syndrome) and 34 with no diagnosis. In a model combining PFA-adenosine diphosphate (ADP), PFA-epinephrine (EPI), and ISTH-BAT overall performance to diagnose IPFDs was low with area under the curves of 0.56 (95% CI 0.44, 0.69) compared with 0.84 (95% CI 0.76, 0.92) for VWD. Correlation of PFA-EPI/-ADP and ISTH-BAT was low with 0.25/0.39 Spearman's correlation coefficients. PFA were significantly prolonged in patients with VWD and Glanzmann thrombasthenia. ISTH-BAT-scores were only positive in severe bleeding disorders, but not in children with mild IPFDs or VWD., Conclusion: Neither ISTH-BAT nor PFA or the combination of both help diagnosing mild IPFDs in children. PFA is suited to exclude severe IPFDs or VWD and is in this regard superior to ISTH-BAT in children., (© 2024 The Authors. European Journal of Haematology published by John Wiley & Sons Ltd.)

May-Thurner syndrome (MTS) is a pelvic venous disorder involving compression of the left common iliac vein by the right common iliac artery, which results in predisposition for deep vein thrombosis. Although MTS is increasingly recognized in young patients, specific guidelines on diagnosis and management for children, adolescents, and young adults do not exist so far. The aim of this study was to assess current diagnostic and therapeutic practice in Germany, Austria, and Switzerland in children and young adults with thrombosis and MTS.We designed an online survey with 11 questions, which we sent via a mailing list to all members of the German, Austrian, and Swiss Society of Thrombosis and Haemostasis Research. Between July and October 2022, 33 specialists answered the questionnaire. Most participating specialists worked at pediatric hospitals (61%). Numbers of annually treated thromboses ranged from <5 (26%) to >30 (13%). Most specialists used venous ultrasound to diagnose deep vein thrombosis, 53% magnetic resonance imaging. Only 25% of specialists systematically screened for MTS in deep vein thrombosis. MTS was managed with anticoagulation (65%), iliac vein stent placement (32%), or balloon angioplasty (13%). In total, 31% of specialists reported to use more than one therapeutic method. Diagnostic and therapeutic approaches for MTS differed between specialists. Lack of standardization resulted in individualized and highly diverse management. Prospective observational clinical studies investigating the outcome of different management strategies including long-term follow-up on outcome and incidence of postthrombotic syndrome will help in defining patient groups who benefit most from revascularizing interventional strategies and developing standardized guidelines., Competing Interests: FC: Support for attending meetings and/or travel: GTH meeting Frankfurt 2023, train ticket and hotel payed by NovoNordiskBG: Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Parexel/CALYX, SIRTex Medical, BAYER, COOK, Siemens/VARIAN, Pharmacept, Ewimed, Guerbet, Terumo, Beacon Bioscience/ICON, Elsai, INARI, IPSEN; Support for attending meetings and/or travel: Parexel/CALYX, SIRTex Medical, BAYER, COOK, Siemens/VARIAN, Pharmacept, Ewimed, Guerbet, Terumo, Beacon Bioscience/ICON, Elsai, INARI, IPSENBZ: Grants or contracts from any entity: Grant funding from CSL Behring, Grant funding from Takeda; Leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid: Leader of the Pediatric commission of the German GTHEL-L: Consulting fees: Boehringer Ingelheim, BMS/Pfizer, Bayer, Leo Pharma; Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Daiichi Sankyo, Boehringer Ingelheim, BMS/Pfizer, Bayer, Leo Pharma, CSL Behring, Astra Zeneca, Norgine, Alexion; Participation on a Data Safety Monitoring Board or Advisory Board: BMS/Pfizer, Boehringer Ingelheim, BayerSH: Consulting fees: Bayer, Boehringer Ingelheim; Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Biomarin, Chugai; Support for attending meetings and/or travel: Biomarin; Participation on a Data Safety Monitoring Board or Advisory Board: Bayer, Boehringer Ingelheim, Sobi, Pfizer; Leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid: ISTHMR: Grants or contracts from any entity: Pfizer, Octapharma, LFB, CSL, SOBI, Takeda, Chugai; Consulting fees: Pfizer, LFB, CSL, SOBI, Takeda, Chugai; Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Pfizer, LFB, CSL, SOBI, Takeda, Chugai; Support for attending meetings and/or travel: Pfizer, Octapharma, LFB, CSL, SOBI, Takeda, Chugai; Participation on a Data Safety Monitoring Board or Advisory Board: Octapharma, CSL, SOBI, Takeda, ChugaiAG, WE, NH have no conflict of interest, (Thieme. All rights reserved.)

Background: Calcium hydroxylapatite-carboxymethylcellulose (CaHA-CMC) injectables have emerged as dual-purpose fillers with bioregenerative and direct filling capabilities., Aims: This study investigates the rheological properties of CaHA-CMC and its CMC carrier gel at various dilutions., Methods: The storage modulus (G'), loss modulus (G″), complex viscosity (η*), loss factor (tan δ), cohesivity, and extrusion force were evaluated for a range of CaHA-CMC aqueous dilutions with an oscillatory rheometer, drop weight testing, and force analysis, respectively., Results: Results revealed a significant decrease in G', η*, and increase in tan(δ) with increasing dilution, indicating a decline in the product's direct filling capabilities. Cohesivity decreased dramatically with dilution, potentially enhancing tissue biointegration and the product's biostimulatory effects. The CMC gel carrier displayed inelastic and non-resilient properties, with rheological changes differing from CaHA-CMC. Dilutional rheology was also correlated with previously published dilution-dependent biostimulatory data where hyperdiluted CaHA-CMC (>1:2) demonstrated a regenerative profile and diluted or hypodiluted mixtures retained meaningful filling properties and increased regeneration., Conclusions: These findings offer a continuum for tailoring the product's rheological profile to match specific tissue requirements. Customizable rheology allows CaHA-CMC to be tuned for either filling and contouring or optimal regenerative effects. Importantly, safety implications related to vascular occlusion suggest that dilutional rheomodulation decreases the risk of vascular events. In conclusion, this study highlights the significant impact of aqueous dilution on the rheological properties of CaHA-CMC and its carrier gel. The findings support the clinical application of tailored dilutions to achieve desired outcomes, providing versatility and safety for aesthetic applications., (© 2024 The Authors. Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.)

Background: &nbsp; Dermal fillers containing calcium hydroxyapatite (CaHA) are categorized as biostimulatory. However, differences in CaHA biomaterial likely affect the resultant induction of collagen synthesis, and variability in microsphere shape and size likely influences a patient&rsquo;s immune response. This study compares 2 CaHA based fillers: one suspended in carboxymethylcellulose (denoted "CaHA/CMC"), and one crosslinked with 1,4-butanediol diglycidyl ether to hyaluronic acid (denoted "CaHA/HA")., Objective: To characterize CaHA/CMC and CaHA/HA fillers to stimulate in vitro collagen biosynthesis., Methods: Physicochemical evaluations included G&prime; and extrusion force. Scanning electron microscopy (SEM) was used to characterize isolated CaHA microspheres and freeze-dried formulations. Collagen I and III expression were evaluated using immunofluorescence., Results: CaHA/CMC showed higher G&prime; (P&lt;0.001) and lower extrusion force (P=0.0003), with uniform polymeric-matrix interactions, compared with CaHA/HA. On SEM, isolated microspheres and freeze-dried CaHA/CMC showed round and smooth surfaced microspheres of similar size. Isolated microspheres and freeze-dried CaHA/HA showed nonhomogeneous, broken microspheres, of various sizes, with fragments embedded in the polymer matrix. Although both fillers induced collagen III expression, only CaHA/CMC induced longer-lasting collagen I expression, with increases of 123% (P=0.007) and 164% (P&lt;0.0001) at 2 and 5 mg/mL, respectively, compared with control. CaHA/CMC also increased collagen I expression at equivalent CaHA microsphere concentrations at 2 (P=0.0052) and 5 mg/mL (P&lt;0.0001), compared with CaHA/HA., Conclusion: The physicochemical characteristics selected for evaluation were more favorable for CaHA/CMC than CaHA/HA. When compared with CaHA/HA, the smooth, homogeneous microsphere composition of CaHA/CMC promoted significantly more collagen I biosynthesis, an essential process for tissue augmentation and long-lasting aesthetic improvement.&nbsp;Citation: Kunzler C, Hartmann C, Nowag B, et al. Comparison of physicochemical characteristics and biostimulatory functions in two calcium hydroxyapatite-based dermal fillers. J Drugs Dermatol. 2023;22(9):910-916. doi:10.36849/JDD.7684.

Drosophila 's dorsal clock neurons (DNs) consist of four clusters (DN 1a s, DN 1p s, DN 2 s, and DN 3 s) that largely differ in size. While the DN 1a s and the DN 2 s encompass only two neurons, the DN 1p s consist of ∼15 neurons, and the DN 3 s comprise ∼40 neurons per brain hemisphere. In comparison to the well-characterized lateral clock neurons (LNs), the neuroanatomy and function of the DNs are still not clear. Over the past decade, numerous studies have addressed their role in the fly's circadian system, leading to several sometimes divergent results. Nonetheless, these studies agreed that the DNs are important to fine-tune activity under light and temperature cycles and play essential roles in linking the output from the LNs to downstream neurons that control sleep and metabolism. Here, we used the Flybow system, specific split-GAL4 lines, trans -Tango, and the recently published fly connectome (called hemibrain) to describe the morphology of the DNs in greater detail, including their synaptic connections to other clock and non-clock neurons. We show that some DN groups are largely heterogenous. While certain DNs are strongly connected with the LNs, others are mainly output neurons that signal to circuits downstream of the clock. Among the latter are mushroom body neurons, central complex neurons, tubercle bulb neurons, neurosecretory cells in the pars intercerebralis, and other still unidentified partners. This heterogeneity of the DNs may explain some of the conflicting results previously found about their functionality. Most importantly, we identify two putative novel communication centers of the clock network: one fiber bundle in the superior lateral protocerebrum running toward the anterior optic tubercle and one fiber hub in the posterior lateral protocerebrum. Both are invaded by several DNs and LNs and might play an instrumental role in the clock network., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Reinhard, Schubert, Bertolini, Hagedorn, Manoli, Sekiguchi, Yoshii, Rieger and Helfrich-Förster.)

Purpose: Minimal residual disease (MRD) helps to accurately assess when children with late bone marrow relapses of B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) will benefit from allogeneic hematopoietic stem-cell transplantation (allo-HSCT). More detailed dissection of MRD response heterogeneity and the specific genetic aberrations could improve current practice., Patients and Methods: MRD was assessed after induction treatment and at different times during relapse treatment until allo-HSCT (indicated in poor responders to induction; MRD ≥ 10 -3 ) for patients being treated for late BCP-ALL bone marrow relapses (n = 413; median follow-up, 9.4 years) in the ALL-REZ BFM 2002 trial/registry (ClinicalTrials.gov identifier: NCT00114348)., Results: Patients with both good (MRD < 10 -3 ) and poor responses to induction treatment reached excellent event-free survival (EFS; 72% v 65%) and overall survival (OS; 82% v 74%). Patients with MRD of 10 -2 or greater after induction had reduced EFS (56%), and their MRD persisted until allo-HSCT more frequently than it did in patients with MRD of 10 -3 or greater to less than 10 -2 ( P = .037). Patients with 25% or more leukemic blasts after induction (early nonresponders) had the poorest prognosis (EFS, 22%). Interestingly, patients with MRD of 10 -3 or greater before allo-HSCT (late nonresponders) still had an EFS of 50% and OS of 63%, which in principle justifies allo-HSCT in these patients. From a panel of selected candidate genes, TP53 alterations (frequency, 8%) were the only genetic alteration with independent prognostic value in any MRD-based response subgroup., Conclusion: After induction treatment, MRD-based treatment stratification resulted in excellent survival in patients with late relapsed BCP-ALL. Prognosis could be further improved in very poor responders by intensifying treatment directly after induction. TP53 alterations can be defined as a novel genetic high-risk marker in all MRD response groups in late relapsed BCP-ALL. Here we identified early and late nonresponders to be considered as events in future trials.

Even though the inpatient rehabilitation of children and adolescents with obesity shows beneficial effects in short term, the relapse rate afterwards is high. Previous attempts to implement successful aftercare programs that are open to all patients were either not successful or have been cancelled. Therefore, a new program was developed and evaluated in terms of feasibility. In a cooperation of a rehabilitation clinic with aftercare specialists, 25 families were enabled to participate. During the inpatient treatment a case management was established to accompany and transfer the patients to the ambulatory care afterwards. The process and the aftercare were evaluated by questionnaires (children/adolescents, parents, aftercare specialists) as well as one-on-one interviews and a focus group with the aftercare specialists that were also analyzed. Results show the feasibility of the program and good satisfaction rates among all participating groups (children/adolescents, parents, aftercare specialists, inpatient rehabilitation center). Thus, the program might be eligible in the treatment process. However, the evaluation of the effectiveness in a randomized controlled study is recommended., Competing Interests: IG ist Vorsitzende der KgAS, UT ist Schatzmeister, MP und RS sind Mitglieder. RS ist Ärztlicher Leiter der Fachklinik Sylt., (© Georg Thieme Verlag KG Stuttgart · New York.)

Drosophila melanogaster is a long-standing model organism in the circadian clock research. A major advantage is the relative small number of about 150 neurons, which built the circadian clock in Drosophila. In our recent work, we focused on the neuroanatomical properties of the lateral neurons of the clock network. By applying the multicolor-labeling technique Flybow we were able to identify the anatomical similarity of the previously described E2 subunit of the evening oscillator of the clock, which is built by the 5th small ventrolateral neuron (5th s-LN v ) and one ITP positive dorsolateral neuron (LN d ). These two clock neurons share the same spatial and functional properties. We found both neurons innervating the same brain areas with similar pre- and postsynaptic sites in the brain. Here the anatomical findings support their shared function as a main evening oscillator in the clock network like also found in previous studies. A second quite surprising finding addresses the large lateral ventral PDF-neurons (l-LN v s). We could show that the four hardly distinguishable l-LN v s consist of two subgroups with different innervation patterns. While three of the neurons reflect the well-known branching pattern reproduced by PDF immunohistochemistry, one neuron per brain hemisphere has a distinguished innervation profile and is restricted only to the proximal part of the medulla-surface. We named this neuron "extra" l-LN v (l-LN v x). We suggest the anatomical findings reflect different functional properties of the two l-LN v subgroups., (© 2018 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.)

The prognosis for children with high-risk relapsed acute lymphoblastic leukemia (ALL) is poor. Here, we assessed the prognostic importance of response during induction and consolidation treatment prior to hematopoietic stem cell transplantation (HSCT) aiming to evaluate the best time to assess minimal residual disease (MRD) for intervention strategies and in future trials in high-risk ALL relapse patients. Included patients (n=125) were treated uniformly according to the ALL-REZ BFM (Berlin-Frankfurt-Münster) 2002 relapse trial (median follow-up time=4.8 years). Patients with MRD ⩾10(-3) after induction treatment (76/119, 64%) or immediately preceding HSCT (19/71, 27%) had a significantly worse probability of disease-free survival 10 years after relapse treatment begin, with 26% (±6%) or 23% (±7%), respectively, compared with 58% (±8%) or 48% (±7%) for patients with MRD <10(-3). Conventional intensive consolidation treatment reduced MRD to <10(-3) before HSCT in 63% of patients, whereas MRD remained high or increased in the rest of this patient group. Our data support that MRD after induction treatment can be used to quantify the activity of different induction treatment strategies in phase II trials. MRD persistence at ⩾10(-3) before HSCT reflects a disease highly resistant to conventional intensive chemotherapy and requiring prospective controlled investigation of new treatment strategies and drugs.

Purpose: Developing new blends of heavier-than-water silicone oil tamponade agents containing high molecular weight polydimethylsiloxane polymer for use in vitreoretinal surgery., Materials and Methods: The viscoelastic properties of heavier-than-water silicone oil blends (30.5% F6H8 + 69.5% polydimethylsiloxane) containing high molecular weight polymer additive at increasing concentrations were measured using a controlled-stress rheometer (TA Instruments Rheolyst AR 1000 N). Emulsification of the blends was induced using a sonication device and a pluronic surfactant as a strong emulsifier. The percentage emulsion area was photographed and measured using ImageJ software. In a second in vitro emulsification assessment, silicone oil blends were dispersed using a high shear homogenizer and the oil-in-water droplets were counted using a coulter counter particle analyser., Results: The addition of the high molecular weight polymer increased shear viscosity and viscoelasticity of the oil blends, which were measureable and to some extent predictable. The in vitro emulsification models produced contradictory results. This demonstrates the difficulty of designing and using in vitro models to evaluate the emulsification tendency of tamponade agents in vivo., Conclusion: Addition of a high molecular weight polymer to heavy silicone oil can increase the viscoelasticity. These findings might contribute to the development of emulsification resistant heavy silicone oils., (© The Author(s) 2015.)

Purpose: To present the development and initial experience of a novel colored perfluorocarbon liquid (PFCL) in vitreoretinal surgery., Methods: This was an experimental laboratory study and prospective human interventional study. F6H8 (Fluoron GmbH) was colored by adding 0.3 g/L blue anthraquinone dye. Subsequently, 20% colored F6H8 was prepared by mixing with perfluorooctane or perfluorodecalin (Fluoron GmbH). The novel product is not yet FDA approved for human application. In the laboratory, the colored PFCL was covered with 1) uncolored PFCL, 2) BSS, and 3) silicone oil. Cell toxicity was evaluated in L929 mouse fibroblasts using a growth inhibition assay. Porcine ex vivo eyes were evaluated after vitrectomy followed by intravitreal and subretinal colored PFCL infusion. A pilot, prospective, noncomparative interventional study was conducted in patients with retinal detachment with proliferative vitreoretinopathy (PVR)., Results: The density of the colored PFLC mixture was 1.664 g/cm for perfluorooctane and 1.802 g/cm for perfluorodecalin. There was no relevant cell growth inhibition with any concentration of colored PFCL tested. Experiments in pigs revealed that infusion of the colored PFCL caused neither staining of the internal limiting membrane nor intravitreal residual droplets. In the prospective study, 9 eyes (75%) underwent surgery for rhegmatogenous retinal detachment with at least grade C PVR. The colored PFCL enabled retinal break examination and detection of residual intravitreal droplets in all surgeries. There was no case of separation or leakage of the dye from the PFCL solution that could have caused unwanted staining of the vitreous or epiretinal surface., Conclusion: The colored PFCL enabled intraoperative maneuvers such as endolaser use. In addition, removal of the colored PFCL was easily achieved at the end of surgery.

Purpose: In children with intermediate risk of relapse of acute lymphoblastic leukemia (ALL), it is essential to identify patients in need of treatment intensification. We hypothesized that the prognosis of patients with unsatisfactory reduction of minimal residual disease (MRD) can be improved by allogeneic hematopoietic stem-cell transplantation (HSCT)., Patients and Methods: In the Acute Lymphoblastic Leukemia-Relapse Study of the Berlin-Frankfurt-Münster Group (ALL-REZ BFM) 2002, patients with an MRD level of ≥ 10(-3) (n = 99) at the end of induction therapy were allocated to HSCT, whereas those with an MRD level less than 10(-3) (n = 109) continued to receive chemotherapy. MRD was quantified by real-time polymerase chain reaction for clone-specific T-cell receptor/immunoglobulin gene rearrangements., Results: The probability of event-free survival for patients with MRD ≥ 10(-3) was 64% ± 5% in ALL-REZ BFM 2002 compared with 18% ± 7% in the predecessor study ALL-REZ BFM P95/96 (P < .001). This was mainly achieved by reducing the cumulative incidence of subsequent relapse (CIR) at 8 years from 59% ± 9% to 27% ± 5% (P < .001). The favorable prognosis of patients with MRD less than 10(-3) could be confirmed in those with a late combined or isolated bone marrow B-cell precursor (BCP) -ALL relapse (CIR, 20% ± 5%), whereas patients with an early combined BCP-ALL relapse had an unfavorable outcome (CIR, 63% ± 13%; P < .001)., Conclusion: Allogeneic HSCT markedly improved the prognosis of patients with intermediate risk of relapse of ALL and unsatisfactory MRD response. As a result, outcomes in this group approximated those of patients with favorable MRD response. Patients with early combined relapse require treatment intensification even in case of favorable MRD response, demonstrating the prognostic impact of time to relapse.

Tumor cell metastasis, a process which increases the morbidity and mortality of cancer patients, is highly dependent upon matrix metalloproteinase (MMP) production. Small molecule inhibitors of MMPs have proven unsuccessful at reducing tumor cell invasion in vivo. Therefore, finding an alternative approach to regulate MMP is an important endeavor. Tetraspanins, a family of cell surface organizers, play a major role in cell signaling events and have been implicated in regulating metastasis in numerous cancer cell lines. We stably expressed tetraspanin CD9 in an invasive and metastatic human fibrosarcoma cell line (CD9-HT1080) to investigate its role in regulating tumor cell invasiveness. CD9-HT1080 cells displayed a highly invasive phenotype as demonstrated by matrigel invasion assays. Statistically significant increases in MMP-9 production and activity were attributed to CD9 expression and were not due to any changes in other key tetraspanin complex members or MMP regulators. Increased invasion of CD9-HT1080 cells was reversed upon silencing of MMP-9 using a MMP-9 specific siRNA. Furthermore, we determined that the second extracellular loop of CD9 was responsible for the upregulation of MMP-9 production and subsequent cell invasion. We demonstrated for the first time that tetraspanin CD9 controls HT1080 cell invasion via upregulation of an integral member of the MMP family, MMP-9. Collectively, our studies provide mounting evidence that altered expression of CD9 may be a novel approach to regulate tumor cell progression.

Background: Perfluorocarbon liquids (PFCLs) are used as intraoperative tools to stabilize the retina during vitreoretinal surgeries. Their use would be much facilitated if PFCLs were colored and not transparent. We describe the development of a colored PFCL for vitreoretinal surgeries., Methods: Perfluorohexyloctan (F6H8) was colored by adding a blue, biocompatible anthraquinone dye, and then mixed with perfluorodecalin (PFD) or perfluorooctane (PFO) at different volume percentages. The thus-obtained colored PFCLs were incubated with lens, lens capsule, vitreous body, and retina of enucleated porcine eyes for staining purpose and analyzed microscopically. To analyze possible interactions between colored PFCLs and silicone oil, colored PFCLs were exchanged to BSS and silicone oil respectively in enucleated pig eyes., Results: By mixing different volume% of colored F6H8 with perfluorodecalin (PFD) or perfluorooctane (PFO), colored PFCLs of different density and staining intensity were obtained. Cornea, lens, lens capsule, vitreous, and retina showed no signs of staining after incubation with colored PFCLs for 10 min. Colored PFCLs were transparent despite intense coloring, thus allowing a clear visibility of the underlying tissue. Immediately after instillation of silicone oil, the colored PFCL bubble was well-defined, and colored PFCL was easily aspirated. After 5 minutes reaction time, considerable diffusion of the dye from the PFCL bubble into the silicone oil was observed., Conclusions: The staining intensity can be varied according to the volume% of the colored F6H8 phase. Colored PFCL is clearly visible when installed in the vitreous cavity of a pig eye, and can easily be removed. It does not stain the intraocular tissues in pig eyes. Colored PFCL can be exchanged with silicone oil. But a time-dependent diffusion of the dye into the silicone oil was observed in pig eyes, indicating that the contact should be limited.

Minimal residual disease (MRD) quantified after induction treatment of childhood acute lymphoblastic leukemia (ALL) predicts risk of relapse. It has been assumed that early relapses derive from a residual population of leukemic cells, which is still present after induction and that relapsed disease will consequently be more resistant to treatment. To test these hypotheses, we performed a prospective study on patients treated according to the frontline-trial ALL-BFM 2000, which used MRD response for risk-group stratification. Patients (n=45) showed a median time to relapse of 1.5 years. In 89% of patients at least one T-cell-receptor/immunoglobulin gene rearrangement chosen for initial MRD quantification remained stable; however, at least one of the preferred markers for MRD stratification at relapse was different to diagnosis in 50% of patients. A similar proportion of very early, early and late relapses appeared to gain a marker at relapse although backtracking-analysis revealed that in 77% of cases, the gained markers were present as small sub-clones at initial diagnosis. Comparing initial and relapse MRD response to induction, 38% of patients showed a similar, 38% a better and 25% a poorer response after relapse. These data demonstrate an unexpectedly high clonal heterogeneity among very early/early relapses and challenge some current assumptions about relapsed ALL.

Purpose: To develop new blends of emulsification-resistant silicone oil based on high molecular weight (HMW) silicone oil for use as an endotamponade in vitreoretinal surgery., Methods: Viscosity and elasticity of various silicone oil blends (Siluron 1000, Siluron 2000, Siluron 5000, 7% HMW + Siluron 1000, 10% HMW + Siluron 1000, and 15% HMW + Siluron 1000; Fluoron GmbH, Ulm, Germany) were measured using a piezoelectric axial vibrator. Emulsification was induced using a sonication device. Pluronic 10%, plasma, and serum were used as emulsifiers. The emulsion area was photographed and measured using ImageJ software (developed by Wayne Rasband, National Institutes of Health, Bethesda, MD; available at http://rsb.info.nih.gov/ij/index.html)., Results: Viscosity increased proportionally to HMW concentrations. Fluid elasticity was optimum using 10% HMW. Emulsification was at a minimum when using 10% or 15% HMW blends., Conclusions: A new silicone oil-based tamponade was developed with a viscosity similar to Siluron 5000 (at 37°C) but with significantly less emulsification tendency than Siluron 5000 or Siluron 2000. HMW concentration increases the fluid elasticity, thereby reducing the emulsification tendency.

A rapid and selective method for simultaneous determination of cyclophosphamide and its metabolite carboxyethylphosphoramide mustard (CEPM) was developed using online sample preparation and separation with tandem mass spectrometric detection. Diluted plasma was injected onto an extraction column (Cyclone MAX 0.5 mm x 50 mm, >30 microm), the sample matrix was washed with an aqueous solution, and retained analytes were transferred to an analytical column (Gemini 3 microm C18 110A, 100 mm x 2.0 mm) using a gradient mobile phase prior to detection by MS/MS. Analytes were detected in an API-3000 LC-MS/MS system using positive multiple-reaction monitoring mode (m/z 261/140 and 293/221 for CTX and CEPM, respectively). Online extraction recoveries were 76% and 72% for cyclophosphamide and CEPM. Within-day and between-day variabilities were <3.0%, and accuracies were between -6.9% and 5.2%. This method has been used to measure plasma cyclophosphamide and CEPM concentrations in an ongoing Phase II study in children with newly diagnosed medulloblastoma.

Purpose: To compare the expression of pregnane xenobiotic receptor and certain multi-drug resistance proteins in retinoblastoma., Methods: Using tissue microarray analyses, we studied 62 pathology specimens for expression of pregnane xenobiotic receptor, multi-drug resistance 1/P glycoprotein, multi-drug resistance proteins 1, 2, and 4, and breast cancer resistant protein., Results: Comparing tumors treated with primary enucleation with tumors treated with chemotherapy and/or radiation showed no significant differences in the expression of multi-drug resistance proteins or pregnane xenobiotic receptor. Pregnane xenobiotic receptor was correlated with multi-drug resistance protein 2 expression (p < 0.001)., Conclusion: Our results indicate selection, rather than induction, of chemoresistant cells as a cause for treatment failure in managing retinoblastoma with primary systemic chemotherapy.

This study investigates the extent of bone marrow (BM) involvement at diagnosis of apparent isolated extramedullary (AIEM) relapses of childhood acute lymphoblastic leukemia (ALL) and its relation to prognosis. Sixty-four children with first AIEM relapse treated in Germany, Czech Republic, or France were included. Real-time quantitative polymerase chain reaction using T-cell receptor and immunoglobulin gene rearrangements provided a sensitive measure of submicroscopic BM involvement, which was detectable at a level of 10(-4) or higher in 46 patients and less than 10(-4) in 11 patients, and was nondetectable (sensitivity: 10(-4)) in 7 patients. In the total cohort, the probability of event-free survival (pEFS) for children with BM involvement of 10(-4) or higher was 0.30 (0.09 +/- SE) versus 0.60 (+/- 0.12) for those with less than 10(-4) (P = .13). The cumulative incidence of subsequent relapse was 0.24 (+/- 0.01) for patients with BM involvement less than 10(-4) and 0.65 (+/- 0.01) for those with 10(-4) or higher (P = .012). Restricted to central nervous system (CNS) relapses, pEFS was 0.11 (+/- 0.09) for patients with BM involvement 10(-4) or higher and 0.63 (+/- 0.17) for those with less than 10(-4) (P = .053). CNS relapses were associated with a higher (> or = 10(-4): 80%) submicroscopic BM involvement than testicular relapses (> or = 10(-4): 57%, P = .08). In summary, we show marked heterogeneity of submicroscopic BM involvement at first AIEM relapse diagnosis in children with ALL, and demonstrate its possible prognostic relevance.

A potential strategy to increase the efficacy of topotecan to treat central nervous system (CNS) malignancies is modulation of the activity of ATP-binding cassette (ABC) transporters at the blood-brain and blood-cerebrospinal fluid barriers to enhance topotecan CNS penetration. This study focused on topotecan penetration into the brain extracellular fluid (ECF) and ventricular cerebrospinal fluid (CSF) in a mouse model and the effect of modulation of ABC transporters at the blood-brain and blood-cerebrospinal fluid barriers by a tyrosine kinase inhibitor (gefitinib). After 4 and 8 mg/kg topotecan i.v., the brain ECF to plasma AUC ratio of unbound topotecan lactone was 0.21 +/- 0.04 and 0.61 +/- 0.16, respectively; the ventricular CSF to plasma AUC ratio was 1.18 +/- 0.10 and 1.30 +/- 0.13, respectively. To study the effect of gefitinib on topotecan CNS penetration, 200 mg/kg gefitinib was administered orally 1 hour before 4 mg/kg topotecan i.v. The brain ECF to plasma AUC ratio of unbound topotecan lactone increased by 1.6-fold to 0.35 +/- 0.04, which was significantly different from the ratio without gefitinib (P < 0.05). The ventricular CSF to plasma AUC ratio significantly decreased to 0.98 +/- 0.05 (P < 0.05). Breast cancer resistance protein 1 (Bcrp1), an efficient topotecan transporter, was detected at the apical aspect of the choroid plexus in FVB mice. In conclusion, topotecan brain ECF penetration was lower compared with ventricular CSF penetration. Gefitinib increased topotecan brain ECF penetration but decreased the ventricular CSF penetration. These results are consistent with the possibility that expression of Bcrp1 and P-glycoprotein at the apical side of the choroid plexus facilitates an influx transport mechanism across the blood-cerebrospinal fluid barrier, resulting in high topotecan CSF penetration.

Purpose: To compare the expression of multidrug-resistant proteins in retinoblastoma tumors among eyes treated with primary enucleation., Methods: A group of 18 patients with unilateral retinoblastoma with advanced intraocular disease was selected for the study. All patients had undergone primary enucleation. A histologic specimen from each patient was retrieved from the pathology archives and a tissue gene microarray was constructed (0.6 x 3-4 mm). Standard immunohistochemical techniques were used to study the tissue microarrays for the expression of the ATP-binding cassette (ABC) transporters: breast cancer resistance protein (BCRP; ABCG2), multidrug-resistant protein 1/P-glycoprotein (MDR1/Pgp; ABCB1), multidrug-resistant-associated protein 1 (MRP1; ABCC1), MRP2 (ABCC2), and MRP4 (ABCC4)., Results: Of the 18 specimens retrieved, 16 had adequate tissue for study. MRP1 was expressed in 8 (50%) of 16 tumors, and MRP2 was expressed in 5 (31%) of 16 tumors. MDR1/Pgp was found in 2 (12%) of 16 retinoblastomas. MRP4 and BCRP were not detected in any of the tumors studied., Conclusions: The results show that multiple ABC transporters were present in a cohort of sporadic patients with unilateral retinoblastoma who underwent primary enucleation. Studies are planned of the expression of ABC transporters in eyes treated by chemotherapy and/or radiation as a comparison with this group.