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1.
Phys Rev Lett ; 129(1): 012001, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35841561

ABSTRACT

We show that the matrix element of a local operator between hadronic states can be used to unambiguously define the associated spatial density. As an explicit example, we consider the charge density of a spinless particle and clarify its relationship to the electric form factor. Our results lead to an unconventional interpretation of the spatial densities of local operators and their moments.

2.
Oncoimmunology ; 10(1): 1935104, 2021 06 06.
Article in English | MEDLINE | ID: mdl-34123576

ABSTRACT

CD103-positive tissue resident memory-like CD8+ T cells (CD8CD103 TRM) are associated with improved prognosis across malignancies, including high-grade serous ovarian cancer (HGSOC). However, whether quantification of CD8, CD103 or both is required to improve existing survival prediction and whether all HGSOC patients or only specific subgroups of patients benefit from infiltration, remains unclear. To address this question, we applied image-based quantification of CD8 and CD103 multiplex immunohistochemistry in the intratumoral and stromal compartments of 268 advanced-stage HGSOC patients from two independent clinical institutions. Infiltration of CD8CD103 immune cell subsets was independent of clinicopathological factors. Our results suggest CD8CD103 TRM quantification as a superior method for prognostication compared to single CD8 or CD103 quantification. A survival benefit of CD8CD103 TRM was observed only in patients treated with primary cytoreductive surgery. Moreover, survival benefit in this group was limited to patients with no macroscopic tumor lesions after surgery. This approach provides novel insights into prognostic stratification of HGSOC patients and may contribute to personalized treatment strategies in the future.


Subject(s)
Cystadenocarcinoma, Serous , Ovarian Neoplasms , CD8-Positive T-Lymphocytes , Female , Humans , Lymphocytes, Tumor-Infiltrating , Prognosis , T-Lymphocyte Subsets
3.
Phys Chem Chem Phys ; 23(25): 14093-14108, 2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34159985

ABSTRACT

Mapping the topological phase behaviour of lipids in aqueous solution is time consuming and finding the ideal lipid system for a desired application is often a matter of trial and error. Modelling techniques that can accurately predict the mesomorphic phase behaviour of lipid systems are therefore of paramount importance. Here, the self-consistent field theory of Scheutjens and Fleer (SF-SCF) in which a lattice refinement has been implemented, is used to scrutinize how various additives modify the self-assembled phase behaviour of monoolein (MO) and 1,2-dioleoyl-phosphatidylcholine (DOPC) lipids in water. The mesomorphic behaviour is inferred from trends in the mechanical properties of equilibrium lipid bilayers with increasing additive content. More specifically, we focus on the Helfrich parameters, that is, the mean and Gaussian bending rigidities (κ and [small kappa, Greek, macron], respectively) supplemented with the spontaneous curvature of the monolayer (Jm0). We use previously established interaction parameters that position the unperturbed DOPC system in the lamellar Lα phase ([small kappa, Greek, macron] < 0, κ > 0 and Jm0 ≈ 0). Similar interaction parameters position the MO system firmly in a bicontinuous cubic phase ([small kappa, Greek, macron] > 0). In line with experimental data, a mixture of MO and DOPC tends to be in one of these two phases, depending on the mixing ratio. Moreover we find good correlations between predicted trends and experimental data concerning the phase changes of MO in response to a wide range of additives. These correlations give credibility to the use of SF-SCF modelling as a valuable tool to quickly explore the mesomorphic phase space of (phospho)lipid bilayer systems including additives.


Subject(s)
Glycerides/chemistry , Lipid Bilayers/chemistry , Phosphatidylcholines/chemistry , Mechanical Phenomena , Models, Molecular , Normal Distribution , Phase Transition , Transition Temperature , Water
4.
Phys Chem Chem Phys ; 23(9): 5152-5175, 2021 Mar 11.
Article in English | MEDLINE | ID: mdl-33624676

ABSTRACT

The self-consistent field theory of Scheutjens and Fleer is implemented on a grid with (lattice) sites that are smaller than the segment size. In this quasi lattice-free implementation we consider united atom-like molecular models and study bilayer self-assembly of phospholipids in a selective solvent (water). We find structural as well as mechanical parameters for these bilayers. The mean (κ) and Gaussian ([small kappa, Greek, macron]) bending moduli, as well as the spontaneous curvature of the monolayer (Jm0), are computed for the first time following a grand canonical ensemble route. Results are in line with previous estimates for mechanical parameters that at the time could not be made following this correct route. This proves that the mean bending modulus is only a very weak function of the membrane tension. We performed a systematic study on the effects of model parameter variations. The mean bending modulus generally grows with increasing bilayer thickness. As expected Jm0 and [small kappa, Greek, macron] behave oppositely with respect to each other and for classical phospholipids assumes values near zero. As an example, an increase in the lipophilic to hydrophilic ratio in the lipids, may cause the Gaussian bending rigidity to switch sign from negative to positive, while - not necessarily at the same point - the spontaneous curvature of the monolayer may switch sign from positive to negative. Together with other investigated trends, these results point to mechanisms of how topological phase transitions of the lipid bilayer membranes may be regulated in the biological context, which correlates with known lipid phase behaviour.

5.
Soft Matter ; 16(29): 6773-6783, 2020 Jul 29.
Article in English | MEDLINE | ID: mdl-32633317

ABSTRACT

Small vesicle aggregates as a model for primitive cellular assemblies or for application as multi-compartment drug delivery systems recently received a lot of interest, yet controlling the aggregation of vesicles to predetermined aggregate sizes remains quite a challenge. We show that this type of control is possible by using a combination of two different linker systems: streptavidin-biotin and C18-pNIPAm. The latter linker is a thermoresponsive surfactant, which below its lower critical solution temperature (LCST) of 32 °C acts as barrier on the outside of the vesicles preventing aggregation, even in the presence of other linkers. Above the LCST however, C18-pNIPAm collapses, becomes sticky and thus acts as a linker inducing aggregation. By working at low vesicle concentrations and tuning the C18-pNIPAm/lipid ratio, the aggregation is by design limited. When the temperature drops below the LCST again, the aggregation is reversed. However, this is not the case if other linkers are present. The collapse of C18-pNIPAm above the LCST provides close contact between vesicles, allowing other linker molecules to connect them. By combining the reversible 'switch-like' aggregation properties of C18-pNIPAm, with the irreversible linkage between biotinylated lipids and streptavidin, it is possible to control the size of the aggregates step by step using a simple temperature program.


Subject(s)
Lipids , Streptavidin , Temperature
6.
Soft Matter ; 16(9): 2379-2389, 2020 Mar 04.
Article in English | MEDLINE | ID: mdl-32064491

ABSTRACT

Lipid vesicles are widely used as model systems to study biological membranes. The self-assembly of such vesicles into vesicle pairs provides further opportunity to study interactions between membranes. However, formation of vesicle pairs, while subsequently keeping their colloidal stability intact, is challenging. Here, we report on three strategies that lead to stable finite-sized aggregates of phospholipid vesicles: (i) vesicles containing biotinylated lipids are coupled together with streptavidin, (ii) bridging attraction is exploited by adding cationic polymers (polylysine) to negatively charged vesicles, and (iii) temperature as a control parameter is used for the aggregation of vesicles mixed with a thermo-sensitive surfactant. While each strategy has its own advantages and disadvantages for vesicle pair formation, the latter strategy additionally shows reversible limited aggregation: above the LCST of pNIPAm, vesicle pairs are formed, while below the LCST, single vesicles prevail. Mixing protocols were assessed by dynamic and static light scattering as well as fluorescence correlation spectroscopy to determine under which conditions vesicle pairs dominate the aggregate size distribution. We have strong indications that without subsequent perturbation, the individual vesicles remain intact and no fusion or leakage between vesicles occurs after vesicle pairs have formed.


Subject(s)
Liposomes/chemistry , Phospholipids/chemistry , Diffusion , Kinetics , Liposomes/chemical synthesis , Polylysine/chemistry
7.
Curr Oncol ; 26(2): e226-e232, 2019 04.
Article in English | MEDLINE | ID: mdl-31043831

ABSTRACT

Background: Data showing the value of neoadjuvant chemotherapy (nact) followed by interval debulking surgery (ids) in the management of advanced-stage serous endometrial carcinoma (eca) are limited; the aim of the present study was to expand the knowledge about that treatment strategy in patients with advanced eca, including endometrioid eca. Methods: Data were collected retrospectively from all patients with advanced-stage eca treated with nact between 2005 and 2014 at 3 oncology referral centres. Primary outcomes were the radiologic response to nact and achievement of optimal or complete ids. Secondary outcomes were recurrence rate and progression-free and overall survival. Results: Of 102 eca cases included, a complete radiologic response was achieved in only 4 cases, with a partial response being achieved in 72% (64% of endometrioid cases, 80% of serous cases). Complete ids was achieved in 62% of the endometrioid cases and in 56% of the serous eca cases, with optimal ids achieved in 31% and 28% of those cases respectively. Survival rates were calculated for all patients with complete and optimal ids; recurrence was observed in 56% and 67% of the cases respectively, and progression-free survival was 18 months and 13 months respectively. Median survival duration was 24 months for endometrioid eca and 28 months for serous eca. Conclusions: For patients with advanced eca who are not suitable for primary debulking, nact followed by ids can be considered regardless of histologic subtype. The treatment options for this group of patients are limited and have to be explored.


Subject(s)
Endometrial Neoplasms/drug therapy , Endometrial Neoplasms/surgery , Adult , Aged , Chemotherapy, Adjuvant , Endometrial Neoplasms/mortality , Endometrial Neoplasms/pathology , Female , Humans , Middle Aged , Neoadjuvant Therapy , Neoplasm Recurrence, Local , Neoplasm Staging , Survival Analysis
8.
Bioorg Chem ; 78: 372-380, 2018 08.
Article in English | MEDLINE | ID: mdl-29627657

ABSTRACT

Treatment of cancer cells by clinically approved hexyl ester of 5-aminolevulinic acid (ALA-Hex) induces accumulation of fluorescent porphyrins in tumors. This allows fluorescence photodiagnosis (PD) of bladder cancer by blue light illumination. However, PD of other cancers is hampered by acute toxicity of the compound limiting its use to local applications. We have designed and synthesized a new prodrug of ALA-Hex that tackles the stability-activity paradox of amino-modified 5-ALA prodrugs. The glucuronide prodrug Glu-ALA-Hex demonstrates excellent stability under physiological conditions and activation in the presence of the target enzyme. ß-glucuronidase-triggered release of 5-ALA is programmed to yield fluorescence in tumor environment with elevated ß-glucuronidase activity, a characteristic of many solid tumors. Glu-ALA-Hex produces similar levels of fluorescence as ALA-Hex in breast cancer MCF7 cells in vitro but with much lower non-specific cell toxicity.


Subject(s)
Aminolevulinic Acid/pharmacology , Antineoplastic Agents/pharmacology , Enzyme Inhibitors/pharmacology , Glucuronidase/antagonists & inhibitors , Photosensitizing Agents/pharmacology , Prodrugs/pharmacology , Aminolevulinic Acid/chemical synthesis , Aminolevulinic Acid/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Fluorescence , Glucuronidase/metabolism , Humans , MCF-7 Cells , Molecular Structure , Photosensitizing Agents/chemical synthesis , Photosensitizing Agents/chemistry , Prodrugs/chemical synthesis , Prodrugs/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured
9.
Neuroimage Clin ; 14: 54-66, 2017.
Article in English | MEDLINE | ID: mdl-28138427

ABSTRACT

The complexity and heterogeneity of neuroimaging findings in individuals with autism spectrum disorder has suggested that many of the underlying alterations are subtle and involve many brain regions and networks. The ability to account for multivariate brain features and identify neuroimaging measures that can be used to characterize individual variation have thus become increasingly important for interpreting and understanding the neurobiological mechanisms of autism. In the present study, we utilize the Mahalanobis distance, a multidimensional counterpart of the Euclidean distance, as an informative index to characterize individual brain variation and deviation in autism. Longitudinal diffusion tensor imaging data from 149 participants (92 diagnosed with autism spectrum disorder and 57 typically developing controls) between 3.1 and 36.83 years of age were acquired over a roughly 10-year period and used to construct the Mahalanobis distance from regional measures of white matter microstructure. Mahalanobis distances were significantly greater and more variable in the autistic individuals as compared to control participants, demonstrating increased atypicalities and variation in the group of individuals diagnosed with autism spectrum disorder. Distributions of multivariate measures were also found to provide greater discrimination and more sensitive delineation between autistic and typically developing individuals than conventional univariate measures, while also being significantly associated with observed traits of the autism group. These results help substantiate autism as a truly heterogeneous neurodevelopmental disorder, while also suggesting that collectively considering neuroimaging measures from multiple brain regions provides improved insight into the diversity of brain measures in autism that is not observed when considering the same regions separately. Distinguishing multidimensional brain relationships may thus be informative for identifying neuroimaging-based phenotypes, as well as help elucidate underlying neural mechanisms of brain variation in autism spectrum disorders.


Subject(s)
Autism Spectrum Disorder/diagnostic imaging , Neural Pathways/diagnostic imaging , White Matter/diagnostic imaging , Adolescent , Adult , Anisotropy , Child , Child, Preschool , Diffusion Magnetic Resonance Imaging , Female , Humans , Image Processing, Computer-Assisted , Longitudinal Studies , Male , Young Adult
10.
Biomicrofluidics ; 10(2): 024114, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27051471

ABSTRACT

Efficient lysis is critical when analyzing single cells in microfluidic droplets, but existing methods utilize detergents that can interfere with the assays to be performed. We demonstrate robust cell lysis without the use of detergents or other chemicals. In our method, cells are exposed to electric field immediately before encapsulation in droplets, resulting in cell lysis. We characterize lysis efficiency as a function of control parameters and demonstrate compatibility with enzymatic assays by measuring the catalysis of ß-glucosidase, an important cellulase used in the conversion of biomass to biofuel. Our method enables assays in microfluidic droplets that are incompatible with detergents.

11.
Br J Anaesth ; 112(5): 852-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24486836

ABSTRACT

BACKGROUND: Post-partum haemorrhage (PPH) causes rapidly developing deficiencies in clotting factors and contributes to substantial maternal morbidity and mortality. Rotational thromboelastometry (ROTEM(®)) is increasingly used as a point of care coagulation monitoring device in patients with massive haemorrhage; however, there are limited data on reference ranges in the peri-partum period. These are required due to the haemostatic changes in pregnancy. METHODS: In a Dutch multi-centre trial, 161 subjects were included; blood samples were obtained during labour (T1) and within 1 h of delivery (T2). Reference ranges of ROTEM(®) INTEM, EXTEM, FIBTEM, and APTEM were set and correlation with laboratory results was investigated using the guidelines of the International Federation of Clinical Chemistry. RESULTS: Reference ranges were obtained for clotting time (CT), clot formation time (CFT), α-angle, clot firmness at 10 and 20 min (A10, A20), maximum clot firmness (MCF), and maximum lysis (ML). These were comparable from centre to centre, and between T1 and T2. Reference ranges T1: EXTEM: CT 31-63 s, CFT 41-120 s, and MCF 42-78 mm. INTEM: CT 109-225 s, CFT 40-103, and MCF 63-78 mm. FIBTEM: CT 31-79 s and MCF 13-45 mm. APTEM: CT 33-62 s, CFT 42-118, and MCF 61-79 mm. CONCLUSIONS: Reference values for ROTEM(®) parameters are reported. The previously published correlation between FIBTEM parameters and plasma fibrinogen levels by the Clauss method is confirmed. Further research is needed to define threshold values for haemostatic therapy in the course of PPH. Clinical trial registration NTR 2515 (http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2515).


Subject(s)
Blood Coagulation/physiology , Monitoring, Physiologic/methods , Postpartum Hemorrhage/diagnosis , Thrombelastography/methods , Adult , Blood Coagulation Tests/methods , Blood Coagulation Tests/statistics & numerical data , Female , Humans , Monitoring, Physiologic/statistics & numerical data , Netherlands , Peripartum Period , Pregnancy , Reference Values , Thrombelastography/statistics & numerical data
13.
Clin Exp Allergy ; 42(6): 901-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22909161

ABSTRACT

BACKGROUND: Increasing evidence links altered intestinal flora in infancy to eczema and asthma. No studies have investigated the influence of maternal intestinal flora on wheezing and eczema in early childhood. OBJECTIVE: To investigate the link between maternal intestinal flora during pregnancy and development of wheeze and eczema in infancy. METHODS: A total of 60 pregnant women from the Boston area gave stool samples during the third trimester of their pregnancy and answered questions during pregnancy about their own health, and about their children's health when the child was 2 and 6 months of age. Quantitative culture was performed on stool samples and measured in log(10)colony-forming units (CFU)/gram stool. Primary outcomes included infant wheeze and eczema in the first 6 months of life. Atopic wheeze, defined as wheeze and eczema, was analysed as a secondary outcome. RESULTS: In multivariate models adjusted for breastfeeding, day care attendance and maternal atopy, higher counts of maternal total aerobes (TA) and enterococci (E) were associated with increased risk of infant wheeze (TA: OR 2.32 for 1 log increase in CFU/g stool [95% CI 1.22, 4.42]; E: OR 1.57 [95% CI 1.06, 2.31]). No organisms were associated with either eczema or atopic wheeze. CONCLUSIONS AND CLINICAL RELEVANCE: In our cohort, higher maternal total aerobes and enterococci were related to increased risk of infant wheeze. Maternal intestinal flora may be an important environmental exposure in early immune system development.


Subject(s)
Environmental Exposure/adverse effects , Intestinal Mucosa/microbiology , Respiratory Sounds/etiology , Adult , Breast Feeding , Eczema/etiology , Female , Humans , Infant , Infant, Newborn , Male , Pregnancy , Risk Factors
14.
Res Autism Spectr Disord ; 6(2): 921-930, 2012.
Article in English | MEDLINE | ID: mdl-22291857

ABSTRACT

Cognitive processing in autism has been characterized by a difficulty with the abstraction of information across multiple stimuli or situations and subsequent generalization to new stimuli or situations. This apparent difficulty leads to the suggestion that prototype formation, a process of creating a mental summary representation of multiple experienced stimuli that go together in a category, may be impaired in autism. Adults with high functioning autism and a typically developing comparison group matched on age and IQ completed a random dot pattern categorization task. Participants with autism demonstrated intact prototype formation in all four ways it was operationally defined, and this performance was not significantly different from that of control participants. However, participants with autism categorized dot patterns that were more highly distorted from the category prototypes less accurately than did control participants. These findings suggest, at least within the constraints of the random dot pattern task, that although prototype formation may not be impaired in autism, difficulties may exist with the generalization of what has been learned about a category to novel stimuli, particularly as they become less similar to the category's prototype.

15.
Neuropharmacology ; 62(2): 1052-61, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22079161

ABSTRACT

L-DOPA-induced dyskinesias (LID) represent a severe complication of long-time pharmacotherapy in Parkinson's disease that necessitates novel therapeutics. The acute and chronic effects of K(V)7.2-7.5 channel openers (retigabine, flupirtine) on the severity of LID and parkinsonian signs were examined in comparison to the glutamate receptor antagonist amantadine (positive control) in a rat model of LID. Acute treatment with retigabine (2.5, 5 mg/kg i.p.) and flupirtine (5, 10 mg/kg i.p.) significantly reduced the severity of abnormal involuntary movements (AIM) to a comparable extent as amantadine (20, 40 mg/kg s.c.), but flupirtine delayed the disappearance of AIM. Chronic treatment with retigabine (daily 5 mg/kg i.p. over 19 days combined with l-DOPA 10 mg i.p.) did not prevent or delay the development of LID, but reduced the severity of AIM, while antidyskinetic effects of amantadine (40 mg/kg i.p.) were restricted to the first day of treatment. Retigabine caused sedation and ataxia which declined during the chronic treatment, but did not reduce the antiparkinsonian effects of l-DOPA in these experiments. Acute co-injections of retigabine (5 mg) together with l-DOPA (10 mg/kg) neither reduced the motor performance in the rotarod test nor exerted negative effects on the antiparkinsonian efficacy of l-DOPA in the block and stepping test. Nevertheless, the sedative effects of retigabine may limit its therapeutic potential for the treatment of LID. The present data indicate that K(V)7 channels deserve attention in the research of the pathophysiology of dyskinesias. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.


Subject(s)
Anticonvulsants/therapeutic use , Carbamates/therapeutic use , Dyskinesia, Drug-Induced/drug therapy , Motor Activity/drug effects , Phenylenediamines/therapeutic use , Stereotyped Behavior/drug effects , Amantadine/pharmacology , Amantadine/therapeutic use , Aminopyridines/pharmacology , Aminopyridines/therapeutic use , Animals , Anticonvulsants/pharmacology , Antiparkinson Agents/pharmacology , Antiparkinson Agents/therapeutic use , Behavior, Animal/drug effects , Carbamates/pharmacology , Female , Oxidopamine/pharmacology , Phenylenediamines/pharmacology , Rats , Rats, Sprague-Dawley
16.
Sahara J (Online) ; 9: 3-10, 2012.
Article in English | AIM (Africa) | ID: biblio-1271518

ABSTRACT

HIV and AIDS is recognized as one of the most devastating pandemics of sub-Saharan Africa; and South Africa in particular; with adverse effect on individuals; families; schools; communities and society at large. Research is therefore required to provide a deeper understanding of the complexities of HIV and AIDS in order to mitigate the effect of the pandemic. Much of the excellent research that has been done has been undertaken within a positivist paradigm and has focused on the biomedical aspects of HIV and AIDS; as well as the social aspects of the pandemic. This theoretical position paper draws on various projects in the field of HIV and AIDS education in rural KwaZulu-Natal to argue that more social science research should be framed within a participatory research paradigm; foregrounding participant engagement and process; and which simultaneously has a 'research-as-intervention' focus. Such research adheres to the requirement of knowledge production; but also engages the participants as knowledge producers who; through the research process; are enabled to shift towards taking up their own agency. Reflecting on the findings from the various projects suggests that visual participatory methodologies are particularly useful when working with marginalized persons whose voices are seldom heard especially when exploring topics which are difficult to discuss. Furthermore; it brings issues to the fore and opens up debate; while at the same time democratizing research and allowing universities to take up their social responsibility and to contribute towards making a difference in the communities they serve


Subject(s)
Acquired Immunodeficiency Syndrome , Community-Based Participatory Research , Clinical Trial , Planning Techniques , Qualitative Research , Social Change , Social Sciences
17.
J Appl Physiol (1985) ; 111(5): 1431-40, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21836049

ABSTRACT

A reduced expression of the manganese-dependent superoxide dismutase (SOD2) is characterized by increased cardiac oxidative stress. Oxidative stress has also been described in situations of physical exercise. We investigated the influence of physical exercise (EX; treadmill 1 h/day at 15 m/min, 5 days/wk, at an angle of 5° for a duration of 8 wk) on cardiac function [heart frequency (HF), echocardiography, morphometry], oxidative stress [reactive oxygen species (ROS)], and antioxidative defence capacity (peroxiredoxin 1-6) in male SOD2-knockout (SOD2_EX) and wild-type mice (WT_EX) compared with untrained age-matched animals (WT_CON; SOD2_CON). In SOD2_CON, heart weight, cardiomyocyte diameter, and cardiac ROS were significantly larger and peroxiredoxin isoforms 4-6 lower than in WT_CON. The vessel-to-cardiomyocyte ratio, cardiac VEGF-concentration, and cardiac function were similar in SOD2_CON and WT_CON. Both groups tolerated the exercise protocol well. In WT, exercise significantly increased vessel-to-cardiomyocyte ratio and ROS-generation and downregulated peroxiredoxin isoforms 4-6 and VEGF generation. The vessel-to-cardiomyocyte ratio, cardiac VEGF concentration, and cardiac ROS were not altered in SOD2_EX compared with SOD2_CON, but a significant upregulation of cardiac peroxiredoxin 1 and 4 was observed. Similar to the result observed in WT_EX, peroxiredoxin 3 was upregulated in SOD2_EX. Chronic exercise shifted the (mal)adaptive hypertrophic into a compensated dilated cardiac phenotype in SOD2_EX. In conclusion, downregulation of SOD2 induces a maladaptive cardiac hypertrophy. In this situation, physical exercise results in a further deterioration of cardiac remodeling despite an upregulation of the antioxidative defense system.


Subject(s)
Adaptation, Physiological/physiology , Heart/physiology , Physical Conditioning, Animal/physiology , Superoxide Dismutase/genetics , Ventricular Remodeling/physiology , Adaptation, Physiological/genetics , Animals , Antioxidants/metabolism , Apoptosis/genetics , Cardiomegaly/genetics , Cardiomegaly/metabolism , Cardiomegaly/physiopathology , Down-Regulation , Heterozygote , Homeostasis , Male , Mice , Mice, Knockout , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/physiology , Oxidation-Reduction , Oxidative Stress/genetics , Oxidative Stress/physiology , Peroxiredoxins/genetics , Protein Isoforms , Reactive Oxygen Species/metabolism , Superoxide Dismutase/deficiency , Up-Regulation , Vascular Endothelial Growth Factor A/metabolism , Ventricular Remodeling/genetics
18.
Curr Med Chem ; 18(12): 1785-805, 2011.
Article in English | MEDLINE | ID: mdl-21466472

ABSTRACT

Clinical studies provide overwhelming evidence for the importance of proteolytic imbalance and the upregulation of diverse protease classes in diseases such as cancer and arthritis. While the complex nature of proteolytic networks has hampered the development of protease inhibitors for these indications, aberrant enzyme activity could be successfully exploited for the development of proteasesensitive drug delivery systems and fluorescent in vivo imaging agents. More recently, these concepts have also been translated into photomedical applications to develop dual modality prodrugs for the simultaneous treatment and imaging of disease. After an introductory overview of proteases and their role in cancer, we present and discuss different strategies to exploit upregulated protease activity for the development of drug delivery systems, fluorescent in vivo reporter probes, and photosensitizer-prodrugs with respect to their potential and limitations. The main approaches used for targeting proteases in all three areas can be roughly divided into peptide-based and macromolecular strategies. Both involve the use of a short, peptide-based protease substrate, which is either directly tagged to the therapeutic agent or dye/quencher pair, or alternatively, serves as a linker between the polymeric carrier and a functional unit. In the latter case, the pharmacokinetic properties of peptide-based protease-sensitive prodrugs and imaging probes can be further ameliorated by the passive targeting capacity of macromolecular drug delivery systems for neoplastic and inflammatory lesions.


Subject(s)
Peptide Hydrolases/therapeutic use , Diagnostic Imaging , Drug Delivery Systems , Humans , Neoplasms/diagnosis , Neoplasms/drug therapy , Photosensitizing Agents , Up-Regulation
19.
J Control Release ; 144(3): 324-31, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20219607

ABSTRACT

The benefit of polymeric immuno-nanoparticles (NPs-Tx-HER), consisting of paclitaxel (Tx)-loaded nanoparticles coated with anti-HER2 monoclonal antibodies (Herceptin, trastuzumab), in cancer treatment was assessed in a disseminated xenograft ovarian cancer model induced by intraperitoneal inoculation of SKOV-3 cells overexpressing HER2 antigens. The study was focused on the evaluation of therapeutic efficacy and biodistribution of NPs-Tx-HER compared to other Tx formulations. The therapeutic efficacy was determined by two methods: bioluminescence imaging and survival rate. The treatment regimen consisted in an initial dose of 20mg/kg Tx administered as 10mg/kg intravenously (IV) and 10mg/kg intraperitonealy (IP), followed by five alternative IP and IV injections of 10mg/kg Tx every 3 days. The bioluminescence study has clearly shown the superior anti-tumor activity of NPs-Tx-HER compared to free Tx. As a confirmation of these results, a significantly longer survival of mice was observed for NPs-Tx-HER treatment compared to free Tx, Tx-loaded nanoparticles coated with an irrelevant mAb (Mabthera, rituximab) or Herceptin alone, indicating the potential of immuno-nanoparticles in cancer treatment. The biodistribution pattern of Tx was assessed on healthy and tumor bearing mice after IV or IP administration. An equivalent biodistribution profile was observed in healthy mice for Tx encapsulated either in uncoated nanoparticles (NPs-Tx) or in NPs-Tx-HER. No significant difference in Tx biodistribution was observed after IV or IP injection, except for a lower accumulation in the lungs when NPs were administered by IP. Encapsulated Tx accumulated in the organs of the reticulo-endothelial system (RES) such as the liver and spleen, whereas free Tx had a non-specific distribution in all tested organs. Compared to free Tx, the single dose injection (IV or IP) of encapsulated Tx in mice bearing tumors induced a higher tumor accumulation. However, no difference in overall tumor accumulation between NPs-Tx-HER and NPs-Tx was observed. In conclusion, the encapsulation of Tx into NPs-Tx-HER immuno-nanoparticles resulted in an improved efficacy of drug in the treatment of disseminated ovarian cancer overexpressing HER2 receptors.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents, Phytogenic/therapeutic use , Drug Carriers/chemistry , Nanoparticles/chemistry , Ovarian Neoplasms/drug therapy , Paclitaxel/therapeutic use , Receptor, ErbB-2/immunology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Monoclonal, Humanized , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/pharmacokinetics , Cell Line, Tumor , Female , Humans , Mice , Paclitaxel/administration & dosage , Paclitaxel/pharmacokinetics , Tissue Distribution , Trastuzumab , Xenograft Model Antitumor Assays
20.
AJNR Am J Neuroradiol ; 31(1): 131-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19749222

ABSTRACT

BACKGROUND AND PURPOSE: Individuals with autism spectrum disorders often exhibit atypical language patterns, including delay of speech onset, literal speech interpretation, and poor recognition of social and emotional cues in speech. We acquired functional MR images during an auditory language task to evaluate systematic differences in language-network activation between control and high-functioning autistic populations. MATERIALS AND METHODS: Forty-one right-handed male subjects (26 high-functioning autistic subjects, 15 controls) were studied by using an auditory phrase-recognition task, and areas of differential activation between groups were identified. Hand preference, verbal intelligence quotient (IQ), age, and language-function testing were included as covariables in the analysis. RESULTS: Control and autistic subjects showed similar language-activation networks, with 2 notable differences. Control subjects showed significantly increased activation in the left posterior insula compared with autistic subjects (P < .05, false discovery rate), and autistic subjects showed increased bilaterality of receptive language compared with control subjects. Higher receptive-language scores on standardized testing were associated with greater activation of the posterior aspect of the left Wernicke area. A higher verbal IQ was associated with greater activation of the bilateral Broca area and involvement of the prefrontal cortex and lateral premotor cortex. CONCLUSIONS: Control subjects showed greater activation of the posterior insula during receptive language, which may correlate with impaired emotive processing of language in autism. Subjects with autism showed greater bilateral activation of receptive-language areas, which was out of proportion to the differences in hand preference in autism and control populations.


Subject(s)
Autistic Disorder/physiopathology , Cerebral Cortex/physiopathology , Language Development Disorders/physiopathology , Magnetic Resonance Imaging , Child , Child, Preschool , Humans , Male
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