Clinical risk prediction model for 30-day all-cause re-hospitalisation or mortality in patients hospitalised with heart failure.

BACKGROUND: This study aimed to develop a risk prediction model (AUS-HF model) for 30-day all-cause re-hospitalisation or death among patients admitted with acute heart failure (HF) to inform follow-up after hospitalisation. The model uses routinely collected measures at point of care. METHODS: We analyzed pooled individual-level data from two cohort studies on acute HF patients followed for 30-days after discharge in 17 hospitals in Victoria, Australia (2014-2017). A set of 58 candidate predictors, commonly recorded in electronic medical records (EMR) including demographic, medical and social measures were considered. We used backward stepwise selection and LASSO for model development, bootstrap for internal validation, C-statistic for discrimination, and calibration slopes and plots for model calibration. RESULTS: The analysis included 1380 patients, 42.1% female, median age 78.7 years (interquartile range = 16.2), 60.0% experienced previous hospitalisation for HF and 333 (24.1%) were re-hospitalised or died within 30 days post-discharge. The final risk model included 10 variables (admission: eGFR, and prescription of anticoagulants and thiazide diuretics; discharge: length of stay>3 days, systolic BP, heart rate, sodium level (<135 mmol/L), >10 prescribed medications, prescription of angiotensin converting enzyme inhibitors or angiotensin receptor blockers, and anticoagulants prescription. The discrimination of the model was moderate (C-statistic = 0.684, 95%CI 0.653, 0.716; optimism estimate = 0.062) with good calibration. CONCLUSIONS: The AUS-HF model incorporating routinely collected point-of-care data from EMRs enables real-time risk estimation and can be easily implemented by clinicians. It can predict with moderate accuracy risk of 30-day hospitalisation or mortality and inform decisions around the intensity of follow-up after hospital discharge.

GAMMA SPECTRUM STABILIZATION FOR ENVIRONMENTAL RADIATION MONITORING STATIONS USING NAI(TL) DETECTOR.

Gamma spectrum measured by an NaI(Tl) detector is known to be unstable with the in situ temperature. In the present work, an advanced method has been applied to stabilize the gamma spectrum measured by the NaI(Tl) detector at environmental radiation monitoring (ERM) stations. The method is based on experimental data obtained under controlled conditions in laboratory. In the temperature range from 4 to 45°C, the relative deviation of the peak positions within the stabilized gamma spectrum is less than 2%. To test this method in a real scenario, it has been integrated into the ERM station at the Military Institute of Chemical and Environmental Engineering in Hanoi, Vietnam. The results show that the proposed method is ready for a real application.

Tissue-specific progesterone receptor-chromatin binding and the regulation of progesterone-dependent gene expression.

Progesterone receptor (PGR) co-ordinately regulates ovulation, fertilisation and embryo implantation through tissue-specific actions, but the mechanisms for divergent PGR action are poorly understood. Here we characterised PGR activity in mouse granulosa cells using combined ChIP-seq for PGR and H3K27ac and gene expression microarray. Comparison of granulosa, uterus and oviduct PGR-dependent genes showed almost complete tissue specificity in PGR target gene profiles. In granulosa cells 82% of identified PGR-regulated genes bound PGR within 3 kb of the gene and PGR binding sites were highly enriched in proximal promoter regions in close proximity to H3K27ac-modified active chromatin. Motif analysis showed highly enriched PGR binding to the PGR response element (GnACAnnnTGTnC), but PGR also interacted significantly with other transcription factor binding motifs. In uterus PGR showed far more tendency to bind intergenic chromatin regions and low evidence of interaction with other transcription factors. This is the first genome-wide description of PGR action in granulosa cells and systematic comparison of diverse PGR action in different reproductive tissues. It clarifies finely-tuned contextual PGR-chromatin interactions with implications for more targeted reproductive medicine.

Haemoglobin expression in in vivo murine preimplantation embryos suggests a role in oxygen-regulated gene expression.

Haemoglobin expression is not restricted to erythroid cells. We investigated the gene expression of the haemoglobin subunits haemoglobin, alpha adult chain 1 (Hba-a1) and haemoglobin, beta (Hbb), 2,3-bisphosphoglycerate mutase (Bpgm) and the oxygen-regulated genes BCL2/adenovirus E1B interacting protein 3 (Bnip3), solute carrier family 2 (facilitated glucose transporter), member 1 (Slc2a1) and N-myc downstream regulated gene 1 (Ndrg1) in the murine preimplantation embryo, comparing invivo to invitro gene expression. Relatively high levels of Hba-a1 and Hbb were expressed invivo from the 2-cell to blastocyst stage; in contrast, little or no expression occurred invitro. We hypothesised that the presence of haemoglobin invivo creates a low oxygen environment to induce oxygen-regulated gene expression, supported by high expression of Slc2a1 and Ndrg1 in invivo relative to invitro embryos. In addition, analysis of an invitro-derived human embryo gene expression public dataset revealed low expression of haemoglobin subunit alpha (HBA) and HBB, and high expression of BPGM. To explore whether there was a developmental stage-specific effect of haemoglobin, we added exogenous haemoglobin either up to the 4-cell stage or throughout development to the blastocyst stage, but observed no difference in blastocyst rate or the inner cell mass to trophectoderm cell ratio. We conclude that haemoglobin in the invivo preimplantation embryo raises an interesting premise of potential mechanisms for oxygen regulation, which may influence oxygen-regulated gene expression.

Dental condition and salivary characteristics in Vietnamese patients with chronic kidney disease.

OBJECTIVES: To determine the dental status and salivary characteristics and to analyse the correlation between creatinine clearance with DMFT index and salivary flow rate in Vietnamese patients with chronic kidney disease (CKD). METHODS: This study was conducted on 111 CKD and 109 non-CKD patients. The socio-demographic characteristics associated with dental habits and xerostomia status were recorded from a self-administered questionnaire. Dental status (DT, MT, FT) and salivary characteristics (flow rate; pH; buffering capacity; urea and creatinine concentrations) were examined. The multivariate regression models were used to assess the correlation of creatinine clearance with DMFT index and salivary flow rate with adjustment for confounders. RESULTS: Patients with CKD made MT and DMFT indices significantly higher than non-CKD subjects. Chronic kidney disease patients had reduced salivary flow rate; but higher xerostomia level, salivary pH and buffering capacity than those in non-CKD subjects. Results of multivariate regression models showed that with lower creatinine clearance 1 mL/min, DMF index was higher 0.02 teeth, and salivary flow rate lower 0.003 mL/min. CONCLUSIONS: There were no differences in dental status between patients with CKD and those without CKD, except that poor renal function is directly related with a higher DMFT index and lower salivary flow rate. Dental professionals should pay greater attention to oral problems during the progression of CKD to prevent deterioration of oral health.

Catecholamine-Dependent ß-Adrenergic Signaling in a Pluripotent Stem Cell Model of Takotsubo Cardiomyopathy.

BACKGROUND: Takotsubo syndrome (TTS) is characterized by an acute left ventricular dysfunction and is associated with life-threating complications in the acute phase. The underlying disease mechanism in TTS is still unknown. A genetic basis has been suggested to be involved in the pathogenesis. OBJECTIVES: The aims of the study were to establish an in vitro induced pluripotent stem cell (iPSC) model of TTS, to test the hypothesis of altered ß-adrenergic signaling in TTS iPSC-cardiomyocytes (CMs), and to explore whether genetic susceptibility underlies the pathophysiology of TTS. METHODS: Somatic cells of patients with TTS and control subjects were reprogrammed to iPSCs and differentiated into CMs. Three-month-old CMs were subjected to catecholamine stimulation to simulate neurohumoral overstimulation. We investigated ß-adrenergic signaling and TTS cardiomyocyte function. RESULTS: Enhanced ß-adrenergic signaling in TTS-iPSC-CMs under catecholamine-induced stress increased expression of the cardiac stress marker NR4A1; cyclic adenosine monophosphate levels; and cyclic adenosine monophosphate-dependent protein kinase A-mediated hyperphosphorylation of RYR2-S2808, PLN-S16, TNI-S23/24, and Cav1.2-S1928, and leads to a reduced calcium time to transient 50% decay. These cellular catecholamine-dependent responses were mainly mediated by ß1-adrenoceptor signaling in TTS. Engineered heart muscles from TTS-iPSC-CMs showed an impaired force of contraction and a higher sensitivity to isoprenaline-stimulated inotropy compared with control subjects. In addition, altered electrical activity and increased lipid accumulation were detected in catecholamine-treated TTS-iPSC-CMs, and were confirmed by differentially expressed lipid transporters CD36 and CPT1C. Furthermore, we uncovered genetic variants in different key regulators of cardiac function. CONCLUSIONS: Enhanced ß-adrenergic signaling and higher sensitivity to catecholamine-induced toxicity were identified as mechanisms associated with the TTS phenotype. (International Takotsubo Registry [InterTAK Registry] [InterTAK]; NCT01947621).

[Quality of life after robotic prostatectomy: Impact of BMI and age on urinary incontinence]. / Qualité de vie après prostatectomie robotique : impact des indices de masse corporelle et âge sur l'incontinence urinaire.

INTRODUCTION: Data evaluating risk factors for urinary incontinence (UI) and quality of life (QoL) after robotic-assisted radical prostatectomy are scarce. The objective of our study was to explore the impact of age and body mass index (BMI) on postoperative incontinence, and the impact of such incontinence and urinary symptoms on QoL. MATERIAL AND METHODS: Two hundred and seventy two patients undergoing robotic-assisted radical prostatectomy answered the questionnaires ICIQ-UI short-form (evaluating UI) and EORTC QoL PR25 (evaluating QoL) in the preoperative setting, then at 1, 3, 12 et 24 months after surgery. Data regarding bother due to UI and urinary symptoms were extrapolated and calculated from the EORT PR25 questionnaire. The modification of ICIQ, of the bother from UI and of urinary symptoms was compared between the preoperative and the early (1-3 months) and late postoperative period (12-24 months). Differences of these scores were explored across non-obese and obese patients, as well as across different age groups. Chi-squared and logistic regression models were performed to test the association between BMI, age and ICIQ score, the bother from UI and urinary symptom score. RESULTS: Median age was 64 years and median BMI was 26.4kg/m2. After surgery, all scores (ICIQ, bother from UI and urinary symptoms) were significantly modified and worsened compared to preoperative values; in particular, median ICIQ passed from 1 to 10, 20% of patients were highly bothered by their urinary symptoms (compared to 2% in the preoperative setting) and the urinary score symptom passed from 8% to 33%. We observed a progressive amelioration of all scores of late controls (12-24 months), with a significantly improved QoL. Across BMI groups, we did not observe any significant difference in terms of modification of ICIQ, of the bother from UI or of urinary symptoms. Moreover, on multivariate logistic regression, BMI was not a risk factor for UI at neither 1 month (P>0.35) nor 12 months (P=0.35). On the other hand, age was significantly associated to an increased risk of UI in the immediate postoperative period on multivariate analysis (P<0.001). Indeed, the rate of patients with an ICIQ≥1 in the immediate postoperative period was higher in men>60 years old compared to younger men<60 years (96% vs 78%, P<0.001). When exploring the QoL scores, we did not observe any significant association between age and QoL, with the exception of an inversion correlation between age and urinary symptoms at 1 month after surgery (P=0.01). CONCLUSION: In this study, after robotic-assisted radical prostatectomy, older men appear to be at increased risk of immediate postoperative incontinence when compared to their younger counterparts, although their QoL is less likely to be bothered. BMI instead was not significantly associated to either urinary incontinence nor to QoL scores as bother form UI and urinary symptoms. LEVEL OF EVIDENCE: 4.

Identification of Human Papilloma Viruses in Atheromatous Coronary Artery Disease.

OBJECTIVE: To identify human papilloma viruses (HPV) in atheromatous coronary arteries. BACKGROUND: Atheromatous arterial disease is primarily an initial inflammatory response to unknown stimuli. The crucial question is "what causes the initial inflammation in atheromatous disease?" HPV infections may be relevant as US women with vaginal, high risk for cancer, HPV infections, are at up to threefold increased risk of cardiovascular disease as compared with vaginal HPV-negative women. These studies did not include analyses of HPV in atheromatous coronary arteries. METHODS: Atheromatous coronary arteries were identified and collected from 20 deceased donors. Polymerase Chain Reaction techniques were used to identify HPV gene sequences. Immunohistochemistry methods were used to identify HPV E7 proteins. RESULTS: HPV types 16 and 18 were identified in 11 (55%) of 20 specimens. HPV E7 protein was identified in 10 (50%) of 20 specimens. Positive and negative HPV identification and HPV E7 expression in coronary smooth muscle cells were significantly correlated (cc = 0.503, p = 0.024). The HPV E7 proteins were expressed in smooth muscle cells and plasma cells, foam cells, and macrophages located in the atheromatous plaque. HPV E7 proteins were not expressed in infiltrating lymph cells. CONCLUSION: HPV gene sequences were identified in 55% of atheromatous coronary arteries and may have a role in coronary artery disease.

Human Papilloma Virus Identification in Breast Cancer Patients with Previous Cervical Neoplasia.

PURPOSE: Women with human papilloma virus (HPV)-associated cervical neoplasia have a higher risk of developing breast cancer than the general female population. The purpose of this study was to (i) identify high-risk HPVs in cervical neoplasia and subsequent HPV positive breast cancers which developed in the same patients and (ii) determine if these HPVs were biologically active. METHODS: A range of polymerase chain reaction and immunohistochemical techniques were used to conduct a retrospective cohort study of cervical precancers and subsequent breast cancers in the same patients. RESULTS: The same high-risk HPV types were identified in both the cervical and breast specimens in 13 (46%) of 28 patients. HPV type 18 was the most prevalent. HPVs appeared to be biologically active as demonstrated by the expression of HPV E7 proteins and the presence of HPV-associated koilocytes. The average age of these patients diagnosed with breast cancer following prior cervical precancer was 51 years, as compared to 60 years for all women with breast cancer (p for difference = 0.001). CONCLUSION: These findings indicate that high-risk HPVs can be associated with cervical neoplasia and subsequent young age breast cancer. However, these associations are unusual and are a very small proportion of breast cancers. These outcomes confirm and extend the observations of two similar previous studies and offer one explanation for the increased prevalence of serious invasive breast cancer among young women.

Human Papilloma Viruses and Breast Cancer.

PURPOSE: Human papillomaviruses (HPV) may have a role in some breast cancers. The purpose of this study is to fill important gaps in the evidence. These gaps are: (i) confirmation of the presence of high risk for cancer HPVs in breast cancers, (ii) evidence of HPV infections in benign breast tissues prior to the development of HPV-positive breast cancer in the same patients, (iii) evidence that HPVs are biologically active and not harmless passengers in breast cancer. METHODS: RNA-seq data from The Cancer Genome Atlas (TCGA) was used to identify HPV RNA sequences in breast cancers. We also conducted a retrospective cohort study based on polymerase chain reaction (PCR) analyses to identify HPVs in archival specimens from Australian women with benign breast biopsies who later developed breast cancer. To assess whether HPVs in breast cancer were biologically active, the expression of the oncogenic protein HPV E7 was assessed by immunohistochemistry (IHC). RESULTS: Thirty (3.5%) low-risk and 20 (2.3%) high-risk HPV types were identified in 855 breast cancers from the TCGA database. The high risk types were HPV 18 (48%), HPV 113 (24%), HPV 16 (10%), HPV 52 (10%). Data from the PCR cohort study indicated that HPV type 18 was the most common type identified in breast cancer specimens (55% of 40 breast cancer specimens) followed by HPV 16 (13%). The same HPV type was identified in both the benign and subsequent breast cancer in 15 patients. HPV E7 proteins were identified in 72% of benign breast specimens and 59% of invasive breast cancer specimens. CONCLUSION: There were four observations of particular interest: (i) confirmation by both NGS and PCR of the presence of high-risk HPV gene sequences in breast cancers, (ii) a correlation between high-risk HPV in benign breast specimens and subsequent HPV-positive breast cancer in the same patient, (iii) HPVs in breast cancer are likely to be biologically active (as shown by transcription of HPV DNA to RNA plus the expression of HPV E7 proteins), (iv) HPV oncogenic influences may occur early in the development of breast cancer.

Role of MMP-2 in the regulation of IL-6/Stat3 survival signaling via interaction with α5ß1 integrin in glioma.

Matrix metalloproteinase-2 (MMP-2) has pivotal role in the degradation of extracellular matrix, and thereby enhances the invasive, proliferative and metastatic potential in cancer. Knockdown of MMP-2 using MMP-2 small interfering RNA (pM) in human glioma xenograft cell lines 4910 and 5310 decreased cell proliferation compared with mock and pSV (scrambled vector) treatments, as determined by 5-bromo-2'-deoxyuridine incorporation, Ki-67 staining and clonogenic survival assay. Cytokine array and western blotting using tumor-conditioned media displayed modulated secretory levels of various cytokines including granulocyte-macrophage colony-stimulating factor, interleukin-6 (IL-6), IL-8, IL-10, tumor necrosis factor-α, angiogenin, vascular endothelial growth factor and PDGF-BB in MMP-2 knockdown cells. Further, cDNA PCR array indicated potential negative regulation of Janus kinase/Stat3 pathway in pM-treated cells. Mechanistically, MMP-2 is involved in complex formation with α5 and ß1 integrins and MMP-2 downregulation inhibited α5ß1 integrin-mediated Stat3 phosphorylation and nuclear translocation. Electrophoretic mobility shift assay and chromatin immunoprecipitation assays showed inhibited Stat3 DNA-binding activity and recruitment at CyclinD1 and c-Myc promoters in pM-treated cells. In individual experiments, IL-6 or siRNA-insensitive MMP-2 overexpression by pM-FL-A141G counteracted and restored the pM-inhibited Stat3 DNA-binding activity, suggesting IL-6/Stat3 signaling suppression in pM-treated 4910 and 5310 cells. MMP-2/α5ß1 binding is enhanced in human recombinant MMP-2 treatments, resulting in elevated Stat3 DNA-binding activity and recruitment on CyclinD1 and c-Myc promoters. Activation of α5ß1 signaling by Fibronectin adhesion elevated pM-inhibited Stat3 phosphorylation whereas blocking α5ß1 abrogated constitutive Stat3 activation. In vivo experiments with orthotropic tumor model revealed the decreased tumor size in pM treatment compared with mock or pSV treatments. Immunofluorescence studies in tumor sections corroborated our in vitro findings evidencing high expression and co-localization of MMP-2/α5ß1, which is decreased upon pM treatment along with significantly reduced IL-6, phospho-Stat3, CyclinD1, c-Myc, Ki-67 and PCNA expression levels. Our data indicate the possible role of MMP-2/α5ß1 interaction in the regulation of α5ß1-mediated IL-6/Stat3 signaling activation and signifies the therapeutic potential of blocking MMP-2/α5ß1 interaction in glioma treatment.

Females do not have increased risk of early or late mortality after isolated aortic valve replacement: results from a multi-institutional Australian study.

AIM: There is controversy regarding whether isolated aortic valve replacement (AVR) in women is associated with an increased risk of early and late mortality. The current study evaluates the impact of gender as an independent risk factor for early and late mortality after isolated AVR. METHODS: Data obtained between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program was retrospectively analysed. Demographic, operative data and postoperative complications were compared between male and female patients using χ(2) and t-tests. Long-term survival analysis was performed using Kaplan Meier survival curves and the log rank test. Independent risk factors for short term and long term mortality were identified using binary logistic and Cox regression, respectively. RESULTS: Isolated aortic valve replacement was undertaken for 2790 patients in 18 Australian institutions; 41.9% were female. Female patients were generally older (mean age 72 vs. 66 years (P<0.001) and presented more often with hypertension (P<0.001) and obesity (P<0.001). They were less likely to present with cerebrovascular disease (P=0.018), renal failure (P=0.017) and non-elective presentation (P=0.017). Women were observed to have a lower 30-day mortality (1.7% vs. 2.1%) but there was no difference on univariate (P=0.490) or multivariate analysis (P=0.983). There was no difference in the incidence of early complications but women were more likely to require red blood cell transfusion (P<0.001). Long-term survival was comparable between men and women (P=0.662). CONCLUSION: Female patients undergoing isolated AVR do not have an increased risk of early and late mortality. Further investigation is required to delineate the impact of gender on early and late outcomes following AVR.

The Brown Norway opticospinal model of demyelination: does it mimic multiple sclerosis or neuromyelitis optica?

Opticospinal demyelinating diseases in humans are mostly characterized by the opticospinal form of multiple sclerosis (MS) and neuromyelitis optica (NMO). Increasing attention has recently focused on astrocyte markers, aquaporin-4 (AQP4) and glial fibrillary acidic protein (GFAP) in these diseases. We induced opticospinal demyelination in Brown Norway rats with soluble recombinant rat myelin oligodendrocyte glycoprotein (1-116) and incomplete Freund's adjuvant. Clinical, MRI, neuropathological and immunological evaluations were performed, with a focus on AQP4 and GFAP. We confirmed the opticospinal phenotype, including extensive myelitis, but also showed the MRI-characterized involvement of the periventricular area. Expression levels of myelin, AQP4 and GFAP showed the early involvement of astrocytes before demyelination in the optic nerve. The overexpression of AQP4 was particularly pronounced in the spinal cord and was concomitant with demyelination and astrocyte apoptosis. The disability scores were correlated with demyelination and inflammation but not with AQP4/GFAP expression. No antibodies against the linear and conformational epitopes of AQP4 were detected. Whereas a NMO-like phenotype was observed in this model, the AQP4/GFAP expression during the disease process was more closely related to opticospinal MS than NMO. However, this model raises the question of a continuum between opticospinal MS and the seronegative NMO subtype.

Swallowing disorders, pneumonia and respiratory tract infectious disease in the elderly.

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).

Cathepsin B and uPAR knockdown inhibits tumor-induced angiogenesis by modulating VEGF expression in glioma.

Angiogenesis, which is the process of sprouting of new blood vessels from pre-existing vessels, is vital for tumor progression. Proteolytic remodeling of extracellular matrix is a key event in vessel sprouting during angiogenesis. Urokinase type plasminogen activator receptor (uPAR) and cathepsin B are both known to be overexpressed and implicated in tumor angiogenesis. In the present study, we observed that knockdown of uPAR and cathepsin B using puPAR (pU), pCathepsin B (pC), and a bicistronic construct of uPAR and cathepsin B (pCU) caused significant inhibition of angiogenesis by disrupting the janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway-dependent expression of vascular endothelial growth factor (VEGF). Further, transcriptional suppression of uPAR and cathepsin B inhibited tumor-induced migration, proliferation of endothelial cells and decreased tumor-promoted expression of VEGF receptor-2, Rac1, gp91phox, cyclin D1, cyclin dependent kinase 4 and p-Rb in human dermal microvascular endothelial cell. Furthermore, U251 and SNB19 xenograft tissue sections from nude mice treated with pCU showed reduced expression of VEGF and CD31, which is a blood vessel visualization marker. Overall, results revealed that knockdown of uPAR and cathepsin B inhibited tumor-induced angiogenesis by disrupting the JAK/STAT pathway-dependent expression of VEGF. These data provide new insight in characterizing the pathways involved in the angiogenic cascade and for the identification of novel target proteins for use in therapeutic intervention for gliomas.

MMP-2 mediates mesenchymal stem cell tropism towards medulloblastoma tumors.

Matrix metalloproteinases (MMPs) are a family of proteinases known to have a role in cell migration. In the present study, we evaluated the role of MMP-2 on tropism of human umbilical cord blood-derived stem cells (hUCBSCs) in a human medulloblastoma tumor model. Consequences of MMP-2 inhibition on stem cell tropism towards medulloblastoma were studied in terms of stem cell migration by using cell culture inserts, transwell chamber assay, western blotting for MMP-2 and migratory molecules, and immunohistochemistry. Conditioned medium from Daoy/D283 cells infected with adenoviral vector encoding MMP-2 small interfering RNA (siRNA) (Ad-MMP-2 si)-reduced stem cell migration as compared with conditioned medium from mock and scrambled vector (Ad-SV) infected cells. In addition, MMP-2 inhibition in the tumor cells decreased the expression of stromal cell-derived factor 1 (SDF1) in the tumor-conditioned medium, which results in impaired SDF1/CXCR4 signaling leading to decreased stem cell tropism towards the tumor cells. We further show that MMP-2 inhibition in the tumor cells repressed stem cell tropism towards medulloblastoma tumors in vivo. In summary, we conclude that hUCBSCs can integrate into human medulloblastoma after local delivery and that MMP-2 expression by the tumor cells mediates this response through the SDF1/CXCR4 axis.

Cathepsin B facilitates autophagy-mediated apoptosis in SPARC overexpressed primitive neuroectodermal tumor cells.

Medulloblastoma and neuroblastoma belong to a group of neoplasms designated as primitive neuroectodermal tumors (PNETs). Secreted protein, acidic and rich in cysteine (SPARC) is a matrix-associated glycoprotein that influences a variety of cellular activities in vitro and in vivo. In this study, we provide evidence that expression of SPARC cDNA induces autophagy in PNET cells followed by apoptotic cell death. SPARC-induced autophagy was morphologically characterized by (i) the formation of membrane-bound autophagic vacuoles (AVOs), (ii) increase in the levels of microtubule-associated protein light chain 3 (LC3) and (iii) induction of the lysososmal enzyme cathepsin B. Cathepsin B, in turn induced mitochondrial release of cytochrome c and activated caspase-3, events that signify the onset of apoptotic cell death. In agreement with these observations, inhibition of autophagy by 3-MA reduced AVO formation and LC3 and inhibited apoptosis, suggesting that autophagy has a role in SPARC-mediated apoptosis. Blocking cathepsin B expression with a specific inhibitor of cathepsin B suppressed apoptosis but did not affect autophagy, which suggests that cathepsin B is a molecular link between autophagy and apoptosis. In summary, these findings show that SPARC expression induces autophagy, which results in the elevation of cathepsin B and subsequent mitochondria-mediated apoptosis.

The role of MMP-9 in the anti-angiogenic effect of secreted protein acidic and rich in cysteine.

BACKGROUND: Secreted protein acidic and rich in cysteine (SPARC), a matricellular glycoprotein, modulates cellular interaction with the extracellular matrix and is capable of altering the growth of various cancers. We therefore sought to determine the effect of SPARC expression on medulloblastoma tumour growth and angiogenesis. METHODS: To this extent, we selected three SPARC full-length cDNA overexpressed clones (Daoy-SP). Consequences of SPARC overexpression were studied in terms of cell growth, angiogenesis using co-culture assay in vitro, dorsal skin-fold chamber assay in vivo, PCR Array for human angiogenic genes, as well as western blotting for angiogenic molecules and tumour growth, in an orthotopic tumour model. RESULTS: The SPARC protein and mRNA levels were increased by approximately three-fold in Daoy-SP cells compared with parental (Daoy-P) and vector (Daoy-EV) controls. Daoy-SP clones reduced tumour cell-induced angiogenesis in vitro and in vivo, and formed small tumours with fewer blood vessels when compared with controls. Matrix metalloprotease-9 (MMP-9) and vascular endothelial growth factor (VEGF) expression were decreased in Daoy-SP clones. Further, inhibition of MMP-9 expression caused SPARC-mediated inhibition of angiogenesis and tumour growth as MMP-9 rescued SPARC-mediated anti-angiogenic effect in vitro and tumour growth inhibition in vivo. CONCLUSION: Overexpression of SPARC decreases angiogenesis, which leads to decreased tumour growth. Further, the role of MMP-9 could be attributed to the anti-angiogenic effect of SPARC.

[Swallowing disorders, pneumonia and respiratory tract infectious disease in the elderly]. / Troubles de la déglutition du sujet âgé et pneumopathies en 14 questions/réponses.

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).

Adenovirus-mediated transfer of siRNA against MMP-2 mRNA results in impaired invasion and tumor-induced angiogenesis, induces apoptosis in vitro and inhibits tumor growth in vivo in glioblastoma.

Invasive tumors, including gliomas, utilize proteinases to degrade extracellular matrix components and diffuse into the adjacent tissues or migrate toward distant ones. In addition, proteinase activity is required for the formation of new blood vessels within the tumor. Levels of the proteinase matrix metalloproteinase-2 (MMP-2) are highly increased in gliomas. In this study, we examined the effect of the downregulation of MMP-2 via adenovirus-mediated siRNA in gliomas. Here, we show that siRNA delivery significantly decreased levels of MMP-2 in the glioblastoma cell lines U-87 and U-251. U-87 and U-251 cells showed impaired invasion through matrigel as well as decreased migration from tumor spheroids transfected with adenoviral vector expressing siRNA against MMP-2. Additionally, tumor-induced angiogenesis was decreased in in vitro experiments in cultured human microvascular endothelial cells (HMECs) in serum-free conditioned medium of glioblastoma cells transfected with these constructs and co-cultures of glioma cells with HMECs. We also observed decreased angiogenesis in the in vivo dorsal skin-fold chamber model. Moreover, MMP-2 inhibition induced apoptotic cell death in vitro, and suppressed tumor growth of preestablished U-251 intracranial xenografts in nude mice. Thus, specific targeting of MMP-2 may provide a novel, efficient approach for the treatment of gliomas and improve the poor outcomes of patients with these brain tumors.