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BACKGROUND: Personal Protective Equipment (PPE) Portraits is a hybridized art and medical intervention that lessens the alienating appearance of PPE through wearable, smiling headshot pictures. During the pandemic, the use of these portraits was expanded, but Canadian initiatives offered portraits only to immediate stakeholders. PPE Portraits Canada (PPC) aimed to provide PPE portraits to any Canadian healthcare institution and surveyed healthcare workers (HCW) regarding these portraits' impact. METHODS: University student volunteers founded PPC via online platforms and coast-to-coast collaborations that allowed any HCW nationwide to request a free portrait via an accessible online form. PPC has gathered feedback from participating HCWs directly via an anonymous and bilingual survey. RESULTS: 70% of HCWs wore their portraits "always" or "usually", 69% of HCWs "definitely would" recommend their portrait, 89.5% of HCWs found that the PPE portraits made a difference in their experiences with patients and 74% found the same for their colleagues. The pre- and post-effect of the portraits, led to a 37.5% greater likelihood that HCWs felt "connected" or "very connected" to patients/residents. For the thematic analysis, 70% or more of the comments were rated as positive, with less than 5% of comments being rated as negative. CONCLUSION: This model's logistical framework can be expanded beyond PPE portraits to other initiatives with limited resources, allowing them to reach and positively impact diverse populations. HCW feedback was predominantly positive. The optimal design and impact of PPE portraits on patients and HCWs should be studied further to improve portrait adoption.
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Personal de Salud , Equipo de Protección Personal , Humanos , Canadá , Instituciones de Salud , PandemiasRESUMEN
Chromothripsis, the process of catastrophic shattering and haphazard repair of chromosomes, is a common event in cancer. Whether chromothripsis might constitute an actionable molecular event amenable to therapeutic targeting remains an open question. We describe recurrent chromothripsis of chromosome 21 in a subset of patients in blast phase of a myeloproliferative neoplasm (BP-MPN), which alongside other structural variants leads to amplification of a region of chromosome 21 in â¼25% of patients ('chr21amp'). We report that chr21amp BP-MPN has a particularly aggressive and treatment-resistant phenotype. The chr21amp event is highly clonal and present throughout the hematopoietic hierarchy. DYRK1A , a serine threonine kinase and transcription factor, is the only gene in the 2.7Mb minimally amplified region which showed both increased expression and chromatin accessibility compared to non-chr21amp BP-MPN controls. We demonstrate that DYRK1A is a central node at the nexus of multiple cellular functions critical for BP-MPN development, including DNA repair, STAT signalling and BCL2 overexpression. DYRK1A is essential for BP-MPN cell proliferation in vitro and in vivo , and DYRK1A inhibition synergises with BCL2 targeting to induce BP-MPN cell apoptosis. Collectively, these findings define the chr21amp event as a prognostic biomarker in BP-MPN and link chromothripsis to a druggable target.
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Background: Computed tomography (CT) is increasingly used for assessing skeletal muscle characteristics. In cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD), reduced limb muscle mass predicts poor clinical outcomes. However, the degree to which quantity or quality of respiratory and nonrespiratory muscles is affected by these diseases remains controversial. Methods: Thoracic CT images of 29 CF, 21 COPD and 20 normal spirometry control subjects were analysed to measure indices of muscle quantity (volume or cross-sectional area) and quality (radiodensity) in respiratory (diaphragm, abdominal) and nonrespiratory (pectoralis, lumbar paraspinal) muscles. Multivariable linear regression assessed relationships of CT measurements with body mass index (BMI), forced expiratory volume in 1â s (FEV1) % pred, inflammation and infection biomarkers, nutritional status and CF genotype. Results: Diaphragm volume in CF was significantly higher than in COPD (by 154%) or controls (by 140%). Abdominal muscle area in CF was also greater than in COPD (by 130%). Nonrespiratory muscles in COPD had more low radiodensity muscle (marker of lipid content) compared to CF and controls. In CF but not COPD, higher BMI and FEV1 % pred were independently associated with higher diaphragm and/or abdominal muscle quantity indices. Serum creatinine also predicted respiratory and nonrespiratory muscle quantity in CF, whereas other biomarkers including genotype correlated poorly with muscle CT parameters. Conclusions: Our data suggest that the CF diaphragm undergoes hypertrophic remodelling, whereas in COPD the nonrespiratory muscles show altered muscle quality consistent with greater lipid content. Thoracic CT can thus identify distinctive respiratory and nonrespiratory muscle remodelling signatures associated with different chronic lung diseases.
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Organizational backends and logistics are often complex and many institutions set-up their workflows based on manual and tedious processes that negatively shape their interactions with stakeholders. Incorporating new technologies can be intimidating. However, a plethora of financially and technically accessible resources that do not require any coding knowledge, can be utilized by institutions to enhance their organizational workflow and stakeholder experience. Guided by our own learning experiences in optimal logistical set-up and user design, we wish to highlight five effective and easily implementable tricks to aid higher institutions and student groups in healthcare to accomplish their administrative duties.
Les backends et la logistique des organisations sont souvent complexes et de nombreuses institutions établissent leurs flux de travail sur la base de processus manuels et fastidieux qui influencent négativement leurs interactions avec les parties prenantes. L'intégration de nouvelles technologies peut être intimidante. Cependant, il existe une pléthore de ressources financièrement et techniquement accessibles, qui ne nécessitent aucune connaissance en codage, que les institutions peuvent utiliser pour améliorer leur flux de travail organisationnel et l'expérience des parties prenantes. Guidés par nos propres expériences d'apprentissage en matière de mise en place d'une logistique optimale et de conception pour l'utilisateur, nous souhaitons mettre en avant cinq astuces efficaces et faciles à mettre en Åuvre pour aider les établissements supérieurs et les groupes d'étudiants en soins de santé à accomplir leurs tâches administratives.
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Ventriculo-peritoneal shunt placement is the most commonly performed procedure for the treatment of hydrocephalus. The complication of migration of the distal ventriculo-peritoneal shunt is one of the many complications that occur after ventriculo-peritoneal shunt placement. The migration of the ventriculo-peritoneal shunt through the vagina is infrequently reported in children. The aim of this review is to help all the providers caring for children with ventriculo-peritoneal shunts to identify issues early when encountered with this complication and thus limit morbidity and mortality. We reviewed all cases of migration of ventriculo-peritoneal shunt through the vagina in children less than 18 years of age that were published in the literature using PubMed, Google Scholar, Web of Science, and Cochrane Library. A total of 11 articles met the eligibility criteria and were included in this review among the 93 articles obtained with title and abstract screening. Previous non-shunt-related abdominal operations and shunt revisions are consistent risk factors in all cases. We did not recognize specific approaches to catheter placement or management that could have prevented this complication. Ventriculitis necessitating shunt removal and therapies requiring additional procedures and prolonged hospitalization are the major consequences identified. Awareness of this unusual complication is very important among health care providers such as emergency care health providers who are likely to be the first to encounter these children on initial presentation.
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In patients with chronic obstructive pulmonary disease (COPD), exertional dyspnoea generally arises when there is imbalance between ventilatory demand and capacity, but the neurophysiological mechanisms are unclear. We therefore determined if disparity between elevated inspiratory neural drive (IND) and tidal volume (VT ) responses (neuromechanical dissociation) impacted dyspnoea intensity and quality during exercise, across the COPD severity spectrum. In this two-centre, cross-sectional observational study, 89 participants with COPD divided into tertiles of FEV1 %predicted (Tertile 1 = FEV1 = 87 ± 9%, Tertile 2 = 60 ± 9%, Tertile 3 = 32 ± 8%) and 18 non-smoking controls, completed a symptom-limited cardiopulmonary exercise test (CPET) with measurement of IND by diaphragm electromyography (EMGdi (%max)). The association between increasing dyspnoea intensity and EMGdi (%max) during CPET was strong (r = 0.730, P < 0.001) and not different between the four groups who showed marked heterogeneity in pulmonary gas exchange and mechanical abnormalities. Significant inspiratory constraints (tidal volume/inspiratory capacity (VT /IC) ≥ 70%) and onset of neuromechanical dissociation (EMGdi (%max):VT /IC > 0.75) occurred at progressively lower minute ventilation ( V Ì E ${\dot{V}}_{{\rm{E}}}$ ) from Control to Tertile 3. Lower resting IC meant earlier onset of neuromechanical dissociation, heightened dyspnoea intensity and greater propensity (93% in Tertile 3) to select qualitative descriptors of 'unsatisfied inspiration'. We concluded that, regardless of marked variation in mechanical and pulmonary gas exchange abnormalities in our study sample, exertional dyspnoea intensity was linked to the magnitude of EMGdi (%max). Moreover, onset of critical inspiratory constraints and attendant neuromechanical dissociation amplified dyspnoea intensity at higher exercise intensities. Simple measurements of IC and breathing pattern during CPET provide useful insights into mechanisms of dyspnoea and exercise intolerance in individuals with COPD. KEY POINTS: Dyspnoea during exercise is a common and troublesome symptom reported by patients with chronic obstructive pulmonary disease (COPD) and is linked to an elevated inspiratory neural drive (IND). The precise mechanisms of elevated IND and dyspnoea across the continuum of airflow obstruction severity in COPD remains unclear. The present study sought to determine the mechanisms of elevated IND (by diaphragm EMG, EMGdi (%max)) and dyspnoea during cardiopulmonary exercise testing (CPET) across the continuum of COPD severity. There was a strong association between increasing dyspnoea intensity and EMGdi (%max) during CPET across the COPD continuum despite significant heterogeneity in underlying pulmonary gas exchange and respiratory mechanical impairments. Critical inspiratory constraints occurred at progressively lower ventilation during exercise with worsening severity of COPD. This was associated with the progressively lower resting inspiratory capacity with worsening disease severity. Earlier critical inspiratory constraint was associated with earlier neuromechanical dissociation and greater likelihood of reporting the sensation of 'unsatisfied inspiration'.
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Enfermedad Pulmonar Obstructiva Crónica , Mecánica Respiratoria , Estudios Transversales , Disnea , Prueba de Esfuerzo , Humanos , Pruebas de Función Respiratoria , Mecánica Respiratoria/fisiologíaRESUMEN
Immunohistochemistry for vascular network analysis plays a fundamental role in basic science, translational research and clinical practice. However, identifying vascularization in histological tissue images is time consuming and markedly depends on the operator's experience. In this study, we present "blood vessel detection-BVD", an automatic algorithm for quantitative analysis of blood vessels in immunohistochemical images. BVD is based on extraction and analysis of low-level image features and spatial filtering techniques, which do not require a training phase. BVD algorithm performance was comparatively evaluated on histological sections from three different in vivo experiments. Collectively, 173 independent images were analyzed, and the algorithm's results were compared to those obtained by human operators. The developed BVD algorithm proved to be a robust and versatile tool, being able to quantify number, area, and spatial distribution of blood vessels within all three considered histologic datasets. BVD is provided as an open-source application working on different operating systems. BVD is supported by a user-friendly graphical interface designed to facilitate large-scale analysis.
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Algoritmos , Ingeniería de Tejidos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Inmunohistoquímica , Neovascularización PatológicaRESUMEN
Background: The International Standardization Organization operates the world's most widely recognized quality management system standard, the ISO 9001:2015. In the healthcare sector, the adoption of this standard within an organization helps to improve the overall performance and provides a foundation for development and continuous progress. Our study aims to describe the implementation process of a quality management system according to the ISO 9001:2015 standards in an Angiology Unit of an Italian Univer-sity hospital. Methods: The project was structured in 5 operational phases, which were carried out during a time frame of 14 months (March 2018-May 2019) and entailed several improvement actions associated with quality and safety outputs such as clinical management, clinical practice, safety, and patient-centeredness. Results: Implementation of the quality management system led to the improvement of many aspects of the processes performed in the Angiology Unit, both in the outpatient and day hospital setting. Overall, the project positively impacted on systems for patient safety, particularly in communication and data transmis-sion, and clinical leadership. Conclusions: The implementation of the ISO 9001 certification is a process that apparently may seem ex-pensive in terms of resources used, commitment, work, comparison, but it leads to substantial and always progressive improvements in the offer of Services to the user, safety both for the users and for the healthcare personnel involved, in addition to the care processes that translate into significant benefits in terms of quality of care for patients, as well as management savings for the organization.
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Cardiología , Hospitales , Certificación , Humanos , Seguridad del Paciente , Estándares de ReferenciaRESUMEN
Rationale: Chronic obstructive pulmonary disease (COPD) is associated with abnormal skeletal muscle morphology and function. Objectives: To test the hypothesis that in vivo diaphragm muscle morphology assessed by computed tomography (CT) imaging would be associated with COPD severity, exacerbations, health status, and exercise capacity. Methods: The COPD Morphometry Study is a cross-sectional study that enrolled a clinical sample of smokers with COPD. Spirometry was performed and COPD severity was defined according to guidelines. Three-dimensional left hemidiaphragm morphology was segmented from contiguous axial CT images acquired at maximal inspiration, yielding quantitative measures of diaphragm CT density in Hounsfield units, dome height, and muscle volume. Exacerbations prompting pharmacotherapy or hospitalization in the preceding 12 months and St. George's Respiratory Questionnaire for COPD were assessed. Incremental symptom-limited cycle ergometry quantified peak oxygen uptake ([Formula: see text]o2Peak). Associations were adjusted for age, sex, body height, body mass index, and smoking status. Results: Among 65 smokers with COPD (75% male; [mean ± standard deviation (SD)] 56 ± 26 pack-years; forced expiratory volume in 1 second [FEV1] percentage predicted 55 ± 23%), mean diaphragm CT density was 3.1 ± 10 Hounsfield units, dome height was 5.2 ± 1.3 cm, and muscle volume was 57 ± 24 cm3. A 1-SD decrement in the diaphragm CT density was associated with 8.3% lower FEV1, 3.27-fold higher odds of exacerbation history, 9.7-point higher score on the St. George's Respiratory Questionnaire for COPD, and 2.5 ml/kg/min lower [Formula: see text]o2Peak. A 1-SD decrement in dome height was associated with 11% lower FEV1 and 1.3 ml/kg/min lower [Formula: see text]o2Peak. There were no associations with diaphragm volume observed. Conclusions: CT-assessed diaphragm morphology was associated with COPD severity, exacerbations, impaired health status, and exercise intolerance. The mechanisms and functional impact of lower diaphragm CT density merit investigation.
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Diafragma , Enfermedad Pulmonar Obstructiva Crónica , Estudios Transversales , Diafragma/diagnóstico por imagen , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Monosomy 1p36 is the most common terminal deletion syndrome with an autosomal dominant pattern of inheritance. This syndrome is defined by an extremely wide spectrum of characteristics; however, developmental delay and intellectual disability of various degree are present in all patients and about the 90% of patients have a severe intellectual disability. Dental agenesis or other dental anomalies have not been described in previous reports. CASE PRESENTATION: We report the case of two little sisters born from healthy and non-consanguineous parents, presenting with dental anomalies and one of them with epilepsy, dilated cardiomyopathy with left-ventricular non-compaction, strabismus, history of poor growth, hypotonia and mild language delay. Patients were evaluated in several departments (genetic, child neuropsychiatric, cardiology, odontostomatology, ophthalmology, otorhinolaryngology) of Institute for Maternal and Child Health, IRCCS Burlo Garofolo, Trieste, Italy. They underwent investigations such as electrocardiogram, echocardiogram, dental orthopantomography X-Ray and Computed Tomography, electroencephalograms, abdomen ultrasound, blood tests, IQ tests, genetic analysis. They both have an Intelligence Quotient greater than 70 and a negative neurologic exam. Each sister carries the same 1p36 deletion of about 2.3 Mb. Genetic analysis of the parents' blood samples (Single Nucleotide Polymorphism- array, karyotype and Fluorescent In Situ Hybridization) did not reveal any deletion, translocation or inversion and confirmed the paternity. A third sib of the probands does not carry the 1p36 deletion or other quantitative alterations. CONCLUSION: This report describes a new trait linked to monosomy 1p36, namely a mild intellectual outcome associated with significant dental anomalies. Our finding suggests that 1p36 deletion syndrome may present with a mild cognitive impairment or even with a normal intellectual development: this is very important for the genetic counselling, especially in a prenatal setting. Moreover, we report the third study with recurrent 1p36 deletion syndrome in two siblings, likely due to germline mosaicism. Finally, we believe that the dental anomalies should be investigated in 1p36 deletion syndrome and that the spectrum of the condition could be broader than we assume.
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Células Germinativas , Mosaicismo , Niño , Deleción Cromosómica , Trastornos de los Cromosomas , Cromosomas Humanos Par 1 , Humanos , Hibridación Fluorescente in Situ , ItaliaRESUMEN
Stromal cells, deriving from mesenchymal stromal cells (MSCs), are crucial component of tumour microenvironment and represent key regulators of tumour processes. MSCs can be recruited to the tumour environment and interact with many cellular elements, thus influencing tumour biology. Cell-to-cell communication is in part mediated by the release of extracellular vesicle (EVs). EVs can induce significant molecular changes in recipient cells, delivering bioactive molecules. In this review, we describe the MSC-derived EVs content and discuss their role in different processes related to cancer biology. Furthermore, we summarize chemical or biological EVs modifications aiming to develop more efficient antitumor therapies.
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Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Neoplasias/patología , Microambiente Tumoral/fisiología , Animales , Comunicación Celular/fisiología , Vesículas Extracelulares/patología , Humanos , Células Madre Mesenquimatosas/patología , Neoplasias/metabolismoRESUMEN
Zinc deficiency affects the development of the central nervous system (CNS) through mechanisms only partially understood. We previously showed that zinc deficiency causes CNS oxidative stress, damaging microtubules and impairing protein nuclear shuttling. STAT1 and STAT3 transcription factors, which require nuclear import for their functions, play major roles in CNS development. Thus, we investigated whether zinc deficiency disrupts STAT1 and STAT3 signaling pathways in the developing fetal CNS, characterizing the involvement of oxidative stress and the cytoskeleton in the adverse effects. Maternal (gestation day 0-19) marginal zinc deficiency (MZD) reduced STAT1 and STAT3 tyrosine phosphorylation and their nuclear translocation in the embryonic day 19 (E19) rat brain. Similar effects were observed in zinc depleted IMR-32 neuroblastoma cells, with an associated decrease in STAT1- and STAT3-dependent gene transactivation. Zinc deficiency caused oxidative stress (increased 4-hydroxynonenal-protein adducts) in E19 brain and IMR-32 cells, which was prevented in cells by supplementation with 0.5mM α-lipoic acid (LA). In zinc depleted IMR-32 cells, the low tyrosine phosphorylation of STAT1, but not that of STAT3, recovered upon incubation with LA. STAT1 and STAT3 nuclear transports were also restored by LA. Accordingly, chemical disruption of the cytoskeleton partially reduced STAT1 and STAT3 nuclear levels. In summary, the redox-dependent tyrosine phosphorylation, and oxidant-mediated disruption of the cytoskeleton are involved in the deleterious effects of zinc deficit on STAT1 and STAT3 activation and nuclear translocation. Therefore, disruption of the STAT1 and STAT3 signaling pathways may in part explain the deleterious effects of maternal MZD on fetal brain development.
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Encéfalo/metabolismo , Estrés Oxidativo/efectos de los fármacos , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT3/genética , Zinc/metabolismo , Animales , Encéfalo/crecimiento & desarrollo , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/patología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Humanos , Oxidación-Reducción , Fosforilación , Transporte de Proteínas/efectos de los fármacos , Ratas , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Ácido Tióctico/administración & dosificación , Activación Transcripcional/efectos de los fármacos , Tirosina/metabolismo , Zinc/deficienciaRESUMEN
This paper investigated if marginal zinc nutrition during gestation could affect fetal exposure to glucocorticoids as a consequence of a deregulation of placental 11ßHSD2 expression. Placenta 11ß-hydroxysteroid dehydrogenase type 2 (11ßHSD2) plays a central role as a barrier protecting the fetus from the deleterious effects of excess maternal glucocorticoids. Rats were fed control (25 µg zinc per g diet) or marginal (10 µg zinc per g diet, MZD) zinc diets from day 0 through day 19 (GD19) of gestation. At GD19, corticosterone concentration in plasma, placenta, and amniotic fluid was similar in both groups. However, protein and mRNA levels of placenta 11ßHSD2 were significantly higher (25% and 58%, respectively) in MZD dams than in controls. The main signaling cascades modulating 11ßHSD2 expression were assessed. In MZD placentas the activation of ERK1/2 and of the downstream transcription factor Egr-1 was low, while p38 phosphorylation and SP-1-DNA binding were low compared to the controls. These results point to a central role of ERK1/Egr-1 in the regulation of 11ßHSD2 expression under the conditions of limited zinc availability. In summary, results show that an increase in placenta 11ßHSD2 expression occurs as a consequence of gestational marginal zinc nutrition. This seems to be due to a low tissue zinc-associated deregulation of ERK1/2 rather than to exposure to high maternal glucocorticoid exposure. The deleterious effects on brain development caused by diet-induced marginal zinc deficiency in rats do not seem to be due to fetal exposure to excess glucocorticoids.
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11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , Fenómenos Fisiologicos Nutricionales Maternos , Placenta/enzimología , Zinc/deficiencia , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/análisis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/genética , Animales , Dieta , Femenino , Expresión Génica/fisiología , Edad Gestacional , Glucocorticoides/análisis , Masculino , Proteína Quinasa 1 Activada por Mitógenos/fisiología , Proteína Quinasa 3 Activada por Mitógenos/fisiología , Placenta/química , Embarazo , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Zinc/administración & dosificación , Proteínas Quinasas p38 Activadas por Mitógenos/fisiologíaRESUMEN
PURPOSE: This study was designed to assess the effect of calcium on the efficacy of DEB during revascularization of steno-obstructive SFA lesions. METHODS: Sixty patients with de novo lesions of the superficial femoral artery underwent endovascular treatment with drug eluting balloons (DEB). DEB was selected according to vessel reference diameter (1:1). In case of residual stenosis > 50 % or flow-limiting dissection, postdilatation with conventional balloon or provisional stenting was done. Patients were classified into eight groups according to circumferential distribution of calcium on CT-angiography axial images (from 0° to 360°) and to its length (length < or > 3 cm) evaluated with digital-subtraction-angiography. Ankle-brachial index (ABI), late lumen loss (LLL), target lesion revascularization (TLR), primary (PP) and secondary (SP) patency, major adverse events (MAE), and Rutherford shift were evaluated at 1-year follow-up and correlated with the amount of calcium. RESULTS: Revascularization was successful in all cases. Flow-limiting dissection occurred in five cases (8.3 %) with a higher circumferential degree of calcium and solved in three cases with postdilatation and in the other two with provisional stenting. DEB effect was lower in patients with higher degree of calcium (>270° vs. <90°): ABI 0.71 ± 0.07 versus 0.92 ± 0.07; LLL 0.75 ± 0.21 versus 0.45 ± 0.1; PP 50 versus 100 %; SP 50 versus 100 %; TLR 25 versus 0 %; MAE 25 versus 0 %. CONCLUSIONS: Calcium represents a barrier to optimal drug absorption. Circumferential distribution seems to be the most influencing factor with the worst effect noticed in 360° calcium presence.
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Angioplastia de Balón/instrumentación , Arteriopatías Oclusivas/sangre , Arteriopatías Oclusivas/terapia , Calcio/sangre , Portadores de Fármacos , Procedimientos Endovasculares , Arteria Femoral , Enfermedades Vasculares Periféricas/sangre , Enfermedades Vasculares Periféricas/terapia , Anciano , Angiografía , Arteriopatías Oclusivas/diagnóstico por imagen , Femenino , Humanos , Recuperación del Miembro , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Stents , Resultado del Tratamiento , UltrasonografíaRESUMEN
We present a microfluidic based injection system designed to achieve intracellular delivery of macromolecules by directing a picoliter-jet of a solution towards individual cells. After discussing the concept, we present design specification and criteria, elucidate performance and discuss results. The method has the potential to be quantitative and high throughput, overcoming limitations of current intracellular delivery protocols.
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During meiosis, DNA double-strand breaks (DSBs) are physiologically induced to start the recombination process and promote the formation of interhomologue crossovers (COs), which are required to ensure faithful chromosome segregation into the gametes. The timely repair of DSBs is an essential part of the meiotic programme, as accumulation of unprocessed DSBs during the pachytene stage of meiotic prophase triggers a DNA damage checkpoint response that induces apoptosis of damaged cells. We show that CO-promoting factors MSH-4, MSH-5, and ZHP-3, but not COSA-1, are required for the apoptotic response of the meiotic DNA damage checkpoint. Lack of MSH-4 or MSH-5 suppresses the apoptotic response observed in some DNA repair-defective mutants such as fcd-2 and brc-1 (orthologues of FANCD2 and BRCA1), irrespectively of the amount of DSBs present in pachytene nuclei. Although ionizing radiation fails to induce apoptosis in msh-4/5-mutant backgrounds, it induces transcriptional activation of the apoptosis-activator egl-1, which is controlled by the Caenorhabditis elegans p53 orthologue CEP-1. This finding suggests that MSH-4/5 involvement in the apoptotic response occurs downstream or independently of damage sensing and checkpoint activation. This study establishes a role for pro-CO factors MSH-4/5 and ZHP-3 in the execution of apoptosis at late meiotic prophase following the accumulation of exogenous or endogenous DNA damage.
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Apoptosis/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Reparación del ADN/genética , Proteínas de Unión al ADN/metabolismo , Animales , Apoptosis/efectos de la radiación , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/genética , Roturas del ADN de Doble Cadena , Proteínas de Unión al ADN/genética , Meiosis/genética , Radiación Ionizante , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Activación Transcripcional/efectos de la radiación , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Twenty-one-day-old Wistar rats were fed a diet containing 0.6% cuprizone for 2 weeks. Studies carried out after withdrawal of cuprizone showed histological evidences of marked demyelination in the corpus callosum. Biochemical studies of isolated myelin showed a marked decrease in myelin proteins, phospholipids, and galactocerebrosides as well as a marked decrease in myelin yield. Treatment of these animals with a single intracranial injection of 350 ng of apotransferrin at the time of withdrawal of cuprizone induced a marked increase in myelin deposition resulting in a significantly improved remyelination, evaluated by histological, immunocytochemical, and biochemical parameters, in comparison to what was observed in spontaneous recovery. Immunocytochemical studies of cryotome sections to analyze developmental parameters of the oligodendroglial cell population at the time of termination of cuprizone and at different times thereafter showed that in the untreated animals, there was a marked increase in the number of NG2-BrdU-positive precursor cells together with a marked decrease in MBP expression at the peak of cuprizone-induced demyelination. As expected, the amount of precursor cells decreased markedly during spontaneous remyelination and was accompanied by an increase in MBP reactivity. In the apotransferrin-treated animals, these phenomena occurred much faster, and remyelination was much more efficient than in the untreated controls. The results of this study suggest that apotransferrin is a very active promyelinating agent which could be important for the treatment of certain demyelinating conditions.