The Y-box factor ZONAB/DbpA associates with GEF-H1/Lfc and mediates Rho-stimulated transcription

Epithelial tight junctions recruit different types of signalling proteins that regulate cell proliferation and differentiation. Little is known about how such proteins interact functionally and biochemically with each other. Here, we focus on the Y-box transcription factor ZONAB (zonula occludens 1-associated nucleic-acid-binding protein)/DbpA (DNA-binding protein A) and the Rho GTPase activator guanine nucleotide exchange factor (GEF)-H1/Lbc's first cousin, which are two tight-junction-associated signalling proteins that regulate proliferation. Our data show that the two proteins interact and that ZONAB activity is Rho-dependent. Overexpression of GEF-H1 induces accumulation of ZONAB in the nucleus and activates transcription. Microtubule-affinity regulating kinase/partition-defective-1, another type of GEF-H1-associated signalling protein, remains in the cytoplasm and partially co-localizes with the exchange factor. GEF-H1 and ZONAB are required for expression of endogenous cyclin D1, a crucial RhoA signalling target gene, and GEF-H1-stimulated cyclin D1 promoter activity requires ZONAB. Our data thus indicate that GEF-H1 and ZONAB form a signalling module that mediates Rho-regulated cyclin D1 promoter activation and expression

Spectroscopy of thulium and holmium heavily doped tellurite glasses

In this study, we report spectroscopic properties of Tm3þ and Ho3þ codoped tellurite glasses over a wide dopant concentration range in order to assess their potential laser performance under 790 nm diode laser excitation. The impact of Tm3þ and Ho3þ concentrations is investigated to identify specific candidates for fiber laser operation. The emission cross section is calculated and discussed, as well as the gain coefficient of this type of glasses. Energy transfer microparameters and critical ion distances are determined for 3H4, 3F4 (Tm3þ), and 5I7 (Ho3þ) emission levels in the framework of diffusionlimited regime and dipole-dipole interaction. We also report thermal properties of tested glasse

The frequency of pharmacological pain relief in university neonatal intensive care units

OBJECTIVE: To evaluate the use of drugs to relieve the pain of invasive procedures newborn infants cared for at a university hospital NICU. METHODS: A prospective cohort study of all newborn infants hospitalized in four NICU during October 2001. The following data were collected: demographic data of the hospitalized newborn infants; clinical morbidity; number of potentially painful procedures and frequency of analgesic administration. Factors associated with the use of analgesia in this cohort of patients were studied by multiple linear regression using SPSS 8.0. RESULTS: Ninety-one newborn infants were admitted to the NICU during the study period (1,025 patient-days). Only 25% of the 1,025 patient-days received systemic analgesia. No specific drugs were administered to relieve acute pain during any of the following painful events: arterial punctures, venous, capillary and lumbar punctures or intubations. For chest tube insertion, 100% of newborn infants received specific analgesia. For the insertion of central catheters 8% of the newborn infants received painkillers. Only nine of the 17 newborn infants that underwent surgical procedures received any analgesic dosage during the postoperative period. For 93% of patients under analgesia the drug of choice was fentanyl. The presence of mechanical ventilation increased the chance of newborn infants receiving painkillers by 6.9 times and the presence of chest tube increased this chance by five times. CONCLUSION: It is necessary to train health professionals in order to bridge the gap between scientific knowledge regarding newborn infant pain and clinical practice.OBJETIVO: Verificar a freqüência com que são empregados analgésicos para o alívio da dor desencadeada por procedimentos invasivos em recém-nascidos internados em UTI universitárias e verificar o perfil de uso de medicamentos para o alívio da dor. MÉTODOS: Coorte prospectiva, avaliada entre 1° e 31 de outubro de 2001, de todos os recém-nascidos internados em quatro UTI. Dados coletados: características gerais das unidades; dados demográficos dos recém-nascidos; morbidade clínica e freqüência do emprego de analgésicos. Realizaram-se a análise estatística descritiva e a regressão linear múltipla por meio do SPSS 8.0, para analisar os fatores associados ao uso de analgésicos nesta coorte. RESULTADOS: No período, foram internados 91 recém-nascidos (1.025 pacientes-dia). Apenas 25% dos 1.025 pacientes-dia receberam alguma dose de analgésico por via sistêmica. Não foi administrada nenhuma medicação específica para o alívio da dor aguda durante os seguintes eventos dolorosos: intubações traqueais, punções arteriais, venosas, capilares e lombares. Na inserção de dreno de tórax, 100% dos recém-nascidos receberam analgesia específica e, para a passagem de cateteres centrais, apenas 8%. De 17 recém-nascidos submetidos a procedimentos cirúrgicos, somente nove receberam analgésicos no pós-operatório. O medicamento mais utilizado foi o fentanil (93%). A presença de ventilação mecânica elevou em 6,9 vezes, e a de dreno de tórax em cinco vezes a chance do recém-nascido receber alguma dose de analgésico. CONCLUSÃO: Há necessidade de melhorar a formação dos profissionais de saúde para diminuir a distância entre os conhecimentos científicos existentes a respeito da dor no recém-nascido e a prática clínica.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Disciplina Pediatria NeonatalUniversidade Estadual de Campinas Faculdade de Ciências Médicas Departamento de PediatriaUNICAMP Centro de Atenção Integral à Saúde da MulherUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Medicina Departamento de PediatriaSanta Casa de São Paulo Faculdade de Ciências Médicas Departamento de PediatriaUNIFESP, EPM, Disciplina Pediatria NeonatalSciEL

ZO-1 Guides Tight Junction Assembly and Epithelial Morphogenesis via Cytoskeletal Tension-Dependent and -Independent Functions

Formation and maintenance of tissue barriers require the coordination of cell mechanics and cell–cell junction assembly. Here, we combined methods to modulate ECM stiffness and to measure mechanical forces on adhesion complexes to investigate how tight junctions regulate cell mechanics and epithelial morphogenesis. We found that depletion of the tight junction adaptor ZO-1 disrupted junction assembly and morphogenesis in an ECM stiffness-dependent manner and led to a stiffness-dependant reorganisation of active myosin. Both junction formation and morphogenesis were rescued by inhibition of actomyosin contractility. ZO-1 depletion also impacted mechanical tension at cell-matrix and E-cadherin-based cell–cell adhesions. The effect on E-cadherin also depended on ECM stiffness and correlated with effects of ECM stiffness on actin cytoskeleton organisation. However, ZO-1 knockout also revealed tension-independent functions of ZO-1. ZO-1-deficient cells could assemble functional barriers at low tension, but their tight junctions remained corrupted with strongly reduced and discontinuous recruitment of junctional components. Our results thus reveal that reciprocal regulation between ZO-1 and cell mechanics controls tight junction assembly and epithelial morphogenesis, and that, in a second, tension-independent step, ZO-1 is required to assemble morphologically and structurally fully assembled and functionally normal tight junctions

The Tight Junction Associated Signalling Proteins ZO-1 and ZONAB Regulate Retinal Pigment Epithelium Homeostasis in Mice

Cell-cell adhesion regulates the development and function of epithelia by providing mechanical support and by guiding cell proliferation and differentiation. The tight junction (TJ) protein zonula occludens (ZO)-1 regulates cell proliferation and gene expression by inhibiting the activity of the Y-box transcription factor ZONAB in cultured epithelial cells. We investigated the role of this TJ-associated signalling pathway in the retinal pigment epithelium (RPE) in vivo by lentivirally-mediated overexpression of ZONAB, and knockdown of its cellular inhibitor ZO-1. Both overexpression of ZONAB or knockdown of ZO-1 resulted in increased RPE proliferation, and induced ultrastructural changes of an epithelial-mesenchymal transition (EMT)-like phenotype. Electron microscopy analysis revealed that transduced RPE monolayers were disorganised with increased pyknosis and monolayer breaks, correlating with increased expression of several EMT markers. Moreover, fluorescein angiography analysis demonstrated that the increased proliferation and EMT-like phenotype induced by overexpression of ZONAB or downregulation of ZO-1 resulted in RPE dysfunction. These findings demonstrate that ZO-1 and ZONAB are critical for differentiation and homeostasis of the RPE monolayer and may be involved in RPE disorders such as proliferative vitroretinopathy and atrophic age-related macular degeneration

Anti-Stokes laser cooling in bulk Erbium-doped materials

We report the first observation of anti-Stokes laser-induced cooling in the Er^{3+}:KPb_{2}Cl_{5} crystal and in the Er^{3+}:CNBZn (CdF_{2}-CdCl_{2}-NaF-BaF_{2}-BaCl_{2}-ZnF_{2}) glass. The internal cooling efficiencies have been calculated by using photothermal deflection spectroscopy. Thermal scans acquired with an infrared thermal camera proved the bulk cooling capability of the studied samples. Implications of these results are discussed.Comment: 4 pages, 4 figures. The figures enclosed with this submission are low quality ones. Versions of this paper with high quality figures are available upon reques