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Alzheimer's disease (AD) is the leading cause of dementia, mainly affecting elderly individuals. AD is characterized by ß-amyloid plaques, abnormal tau tangles, neuronal loss, and metabolic disruptions. Recent studies have revealed the involvement of the kynurenine (KP) pathway and the aryl hydrocarbon receptor (AhR) in AD development. The KP pathway metabolizes tryptophan to produce neuroactive substances like kynurenine, kynurenic acid, and quinolinic acid. In AD, high levels of kynurenine and the neurotoxic quinolinic acid are associated with increased neuroinflammation and excitotoxicity; conversely, reduced levels of kynurenic acid, which acts as a glutamate receptor antagonist, compromise neuroprotection. Research has indicated elevated KP metabolites and enzymes in the hippocampus of AD patients and other tissues such as blood, cerebrospinal fluid, and urine. However, the finding that KP metabolites are AD biomarkers in blood, cerebrospinal fluid, and urine has been controversial. This controversy, stemming from the lack of consideration of the specific stage of AD, details of the patient's treatment, cognitive deficits, and psychiatric comorbidities, underscores the need for more comprehensive research. AhR, a ligand-activated transcription factor, regulates immune response, oxidative stress, and xenobiotic metabolism. Various ligands, including tryptophan metabolites, can activate it. Some studies suggest that AhR activation contributes to AD, while others propose that it provides neuroprotection. This discrepancy may be explained by the specific ligands that activate AhR, highlighting the complex relationship between the KP pathway, AhR activation, and AD, where the same pathway can produce both neuroprotective and harmful effects.
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Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta, which results in a prominent reduction of striatal dopamine levels leading to motor alterations. The mechanisms underlying neurodegeneration in PD remain unknown. Here, we generated an induced pluripotent stem cell line from dermal fibroblasts of a Mexican patient diagnosed with sporadic PD (UNAMi002-A) and another cell line from dermal fibroblasts of a patient carrying the point mutation c.1423delC in PINK1 (UNAMi003-A). These patient-derived iPS cell lines offer the possibility of modeling PD and understanding the mechanisms that contribute to dopamine neuron loss.
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Células-Tronco Pluripotentes Induzidas , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Dopaminérgicos/metabolismo , Dopamina/metabolismo , Proteínas Quinases/genética , Mutação/genéticaRESUMO
BACKGROUND: Poor disinfection is the main cause of blood contamination, so its elimination is key to limiting the entry of bacteria into the collection system. With the advancement of antiseptic technology, antiseptics with sterile, disposable applicators are now available. AIM: To evaluate in situ two antiseptics (with and without applicators) for blood banks and to demonstrate in vitro antiseptic activity on bacterial biofilms of importance in transfusion medicine. METHODS: Antiseptic A (2% sterile solution of chlorhexidine gluconate/70% isopropyl alcohol provided with applicator) and bulk antiseptic B (10% povidone-iodine) were evaluated. The deferred blood donor arms were subjected to disinfection with antiseptics A and B and the contralateral arms were cultured to determine the baseline bacterial load (control). Antiseptic activity was assessed by ANOVA and logaritmic reduction values (LRV) and percentage reduction values (PRV) were calculated. Finally, the in vitro activity of antiseptic A was analyzed by confocal laser scanning microscopy (CLSM) on biofilm models. RESULTS: Prior to disinfection tests, commensal and clinically important bacteria were identified; antiseptic A showed post-disinfection bacterial growth rates of zero compared to controls (p < 0.0001). The frequency of bacterial growth with antiseptic B was 74%. A significant difference was identified between both antiseptics, where antiseptic A showed higher activity (p < 0.5468). LRV and PRV were 0.6-2.5/100% and 0.3-1.7/66.7-99.7% for antiseptics A and B, respectively. Through CLSM, disinfectant A (without applicator) showed lower in vitro antiseptic activity on the tested biofilms at the exposure times recommended by the manufacturer. CONCLUSIONS: Sterile solution of chlorhexidine gluconate/isopropyl alcohol with applicator showed advantages disinfection in deferred blood donors over povidone-iodine.
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Anti-Infecciosos Locais , Clorexidina/análogos & derivados , Humanos , Anti-Infecciosos Locais/farmacologia , Povidona-Iodo/farmacologia , 2-Propanol , Bancos de SangueRESUMO
Human embryonic stem cells (hESCs) differentiate into specialized cells, including midbrain dopaminergic neurons (DANs), and Non-human primates (NHPs) injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine develop some alterations observed in Parkinson's disease (PD) patients. Here, we obtained well-characterized DANs from hESCs and transplanted them into two parkinsonian monkeys to assess their behavioral and imaging changes. DANs from hESCs expressed dopaminergic markers, generated action potentials, and released dopamine (DA) in vitro. These neurons were transplanted bilaterally into the putamen of parkinsonian NHPs, and using magnetic resonance imaging techniques, we calculated the fractional anisotropy (FA) and mean diffusivity (MD), both employed for the first time for these purposes, to detect in vivo axonal and cellular density changes in the brain. Likewise, positron-emission tomography scans were performed to evaluate grafted DANs. Histological analyses identified grafted DANs, which were quantified stereologically. After grafting, animals showed signs of partially improved motor behavior in some of the HALLWAY motor tasks. Improvement in motor evaluations was inversely correlated with increases in bilateral FA. MD did not correlate with behavior but presented a negative correlation with FA. We also found higher 11C-DTBZ binding in positron-emission tomography scans associated with grafts. Higher DA levels measured by microdialysis after stimulation with a high-potassium solution or amphetamine were present in grafted animals after ten months, which has not been previously reported. Postmortem analysis of NHP brains showed that transplanted DANs survived in the putamen long-term, without developing tumors, in immunosuppressed animals. Although these results need to be confirmed with larger groups of NHPs, our molecular, behavioral, biochemical, and imaging findings support the integration and survival of human DANs in this pre-clinical PD model.
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Células-Tronco Embrionárias Humanas , Doença de Parkinson , Animais , Humanos , Neurônios Dopaminérgicos/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Haplorrinos/metabolismo , Mesencéfalo/metabolismo , Dopamina/metabolismo , Doença de Parkinson/terapia , Doença de Parkinson/metabolismoRESUMO
The blood-brain barrier is the interface through which the brain interacts with the milieu and consists mainly of a sophisticated network of brain endothelial cells that forms blood vessels and selectively moves molecules inside and outside the brain through multiple mechanisms of transport. Although brain endothelial cell function is crucial for brain homeostasis, their role in neurodegenerative diseases has historically not been considered with the same importance as other brain cells such as microglia, astroglia, neurons, or even molecules such as amyloid beta, Tau, or alpha-synuclein. Alzheimer's disease is the most common neurodegenerative disease, and brain endothelial cell dysfunction has been reported by several groups. However, its impairment has barely been considered as a potential therapeutic target. Here we review the most recent advances in the relationship between Alzheimer's disease and brain endothelial cells commitment and analyze the possible mechanisms through which their alterations contribute to this neurodegenerative disease, highlighting their inflammatory phenotype and the possibility of an impaired secretory pattern of brain endothelial cells that could contribute to the progression of this ailment. Finally, we discuss why shall brain endothelial cells be appreciated as a therapeutic target instead of solely an obstacle for delivering treatments to the injured brain in Alzheimer's disease.
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FAM20C (family with sequence similarity 20, member C) is a serine/threonine-specific protein kinase that is ubiquitously expressed and mainly associated with biomineralization and phosphatemia regulation. It is mostly known due to pathogenic variants causing its deficiency, which results in Raine syndrome (RNS), a sclerosing bone dysplasia with hypophosphatemia. The phenotype is recognized by the skeletal features, which are related to hypophosphorylation of different FAM20C bone-target proteins. However, FAM20C has many targets, including brain proteins and the cerebrospinal fluid phosphoproteome. Individuals with RNS can have developmental delay, intellectual disability, seizures, and structural brain defects, but little is known about FAM20C brain-target-protein dysregulation or about a potential pathogenesis associated with neurologic features. In order to identify the potential FAM20C actions on the brain, an in silico analysis was conducted. Structural and functional defects reported in RNS were described; FAM20C targets and interactors were identified, including their brain expression. Gene ontology of molecular processes, function, and components was completed for these targets, as well as for potential involved signaling pathways and diseases. The BioGRID and Human Protein Atlas databases, the Gorilla tool, and the PANTHER and DisGeNET databases were used. Results show that genes with high expression in the brain are involved in cholesterol and lipoprotein processes, plus axo-dendritic transport and the neuron part. These results could highlight some proteins involved in the neurologic pathogenesis of RNS.
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Microcefalia , Proteínas Quinases , Humanos , Proteínas Quinases/metabolismo , Microcefalia/genética , Encéfalo/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Caseína Quinase I/genética , Caseína Quinase I/metabolismoRESUMO
BACKGROUND: Medical devices can be reservoirs of multidrug-resistant bacteria that may be involved in the acquisition of infections since bacteria with the ability to form biofilms that are difficult to eradicate, mainly in mechanical ventilators. The aim of this work was to evaluate the efficacy of O3 against biofilms of bacteria ESKAPE group through disinfection studies. METHODS: The formation of biofilms of ESKAPE group bacteria was induced in vitro. O3 was injected at different exposure times at a constant dose of 600 mg/h. The recovery of surviving bacteria after O3 treatment was assessed by bacterial counts and biofilm disruption was analyzed. Finally, the viability and integrity of biofilms after O3 treatment was determined by confocal laser scanning microscopy (CLSM). RESULTS: O3 showed bactericidal activity on biofilms from 12 min/7.68 ppm for A. baumannii and C. freundii. P. aeruginosa, K. pneumoniae and S. aureus were killed after 15 min/9.60 ppm. Correlation analyses showed inversely proportional relationships between the variables "disruption versus O3". CLSM revealed that death was time-dependent of biofilms upon O3 exposure. Orthogonal plane analysis showed that bacteria located in the outer region of the biofilms were the ones that initially suffered damage from O3 exposure. CONCLUSIONS: Our findings suggest that this method could be an alternative for the disinfection in mechanical ventilators colonized by bacteria biofilm forming.
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Desinfecção , Ozônio , Humanos , Desinfecção/métodos , Staphylococcus aureus , Ozônio/farmacologia , Biofilmes , Bactérias , Antibacterianos/farmacologiaRESUMO
Parkinson's disease (PD) is a neurodegenerative disease caused by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, which results in motor alterations. The exact mechanisms underlying the dopaminergic neurodegeneration in PD are still unknown. Here, we generated a human induced pluripotent stem cell (iPSC) line from dermal fibroblasts of a Mexican patient diagnosed with sporadic PD. The generated iPS cell line (UNAMi001-A) express pluripotency markers, maintain a normal karyotype and display the ability to differentiate into all three germ layers. This is the first iPSC line from a Mexican patient and will be useful for PD modeling.
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Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Doença de Parkinson , HumanosRESUMO
Alzheimer's disease (AD) is the most common neurodegenerative disorder and its prevalence is increasing. Nowadays, very few drugs effectively reduce AD symptoms and thus, a better understanding of its pathophysiology is vital to design new effective schemes. Presymptomatic neuronal damage caused by the accumulation of Amyloid ß peptide and Tau protein abnormalities remains a challenge, despite recent efforts in drug development. Importantly, therapeutic targets, biomarkers, and diagnostic techniques have emerged to detect and treat AD. Of note, the compromised blood-brain barrier (BBB) and peripheral inflammation in AD are becoming more evident, being harmful factors that contribute to the development of the disease. Perspectives from different pre-clinical and clinical studies link peripheral inflammation with the onset and progression of AD. This review aims to analyze the main factors and the contribution of impaired BBB in AD development. Additionally, we describe the potential therapeutic strategies using stem cells for AD treatment.
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Doença de Alzheimer , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Humanos , Inflamação/metabolismo , Células-Tronco/metabolismoRESUMO
The process of freezing cells or tissues and depositing them in liquid nitrogen at -196 °C is called cryopreservation. Sub-zero temperature is not a physiological condition for cells and water ice crystals represent the main problem since they induce cell death, principally in large cells like oocytes, which have a meiotic spindle that degenerates during this process. Significantly, cryopreservation represents an option for fertility preservation in patients who develop gonadal failure for any condition and those who want to freeze their germ cells for later use. The possibility of freezing sperm, oocytes, and embryos has been available for a long time, and in 1983 the first birth with thawed oocytes was achieved. From the mid-2000s forward, the use of egg vitrification through intracytoplasmic sperm injection has improved pregnancy rates. Births using assisted reproductive technologies (ART) have some adverse conditions and events. These risks could be associated with ART procedures or related to infertility. Cryopreservation generates changes in the epigenome of gametes and embryos, given that ART occurs when the epigenome is most vulnerable. Furthermore, cryoprotective agents induce alterations in the integrity of germ cells and embryos. Notably, cryopreservation extensively affects cell viability, generates proteomic profile changes, compromises crucial cellular functions, and alters sperm motility. This technique has been widely employed since the 1980s and there is a lack of knowledge about molecular changes. The emerging view is that molecular changes are associated with cryopreservation, affecting metabolism, cytoarchitecture, calcium homeostasis, epigenetic state, and cell survival, which compromise the fertilization in ART.
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Cálcio/metabolismo , Criopreservação/normas , Embrião de Mamíferos/citologia , Epigênese Genética , Células Germinativas/citologia , Infertilidade/terapia , Proteoma/metabolismo , Sobrevivência Celular , Crioprotetores/química , Feminino , Preservação da Fertilidade/normas , Fertilização in vitro , Células Germinativas/metabolismo , Humanos , Infertilidade/metabolismo , Infertilidade/patologia , Masculino , Oócitos/citologia , Oócitos/metabolismo , Gravidez , Espermatozoides/citologia , Espermatozoides/metabolismoRESUMO
FAM20C is a gene coding for a protein kinase that targets S-X-E/pS motifs on different phosphoproteins belonging to diverse tissues. Pathogenic variants of FAM20C are responsible for Raine syndrome (RS), initially described as a lethal and congenital osteosclerotic dysplasia characterized by generalized atherosclerosis with periosteal bone formation, characteristic facial dysmorphisms and intracerebral calcifications. The aim of this review is to give an overview of targets and variants of FAM20C as well as RS aspects. We performed a wide phenotypic review focusing on clinical aspects and differences between all lethal (LRS) and non-lethal (NLRS) reported cases, besides the FAM20C pathogenic variant description for each. As new targets of FAM20C kinase have been identified, we reviewed FAM20C targets and their functions in bone and other tissues, with emphasis on novel targets not previously considered. We found the classic lethal and milder non-lethal phenotypes. The milder phenotype is defined by a large spectrum ranging from osteonecrosis to osteosclerosis with additional congenital defects or intellectual disability in some cases. We discuss our current understanding of FAM20C deficiency, its mechanism in RS through classic FAM20C targets in bone tissue and its potential biological relevance through novel targets in non-bone tissues.
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Anormalidades Múltiplas , Caseína Quinase I , Fissura Palatina , Exoftalmia , Proteínas da Matriz Extracelular , Variação Genética , Microcefalia , Osteosclerose , Fenótipo , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/metabolismo , Anormalidades Múltiplas/mortalidade , Anormalidades Múltiplas/patologia , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Fissura Palatina/genética , Fissura Palatina/metabolismo , Fissura Palatina/mortalidade , Fissura Palatina/patologia , Exoftalmia/genética , Exoftalmia/metabolismo , Exoftalmia/mortalidade , Exoftalmia/patologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Humanos , Microcefalia/genética , Microcefalia/metabolismo , Microcefalia/mortalidade , Microcefalia/patologia , Osteosclerose/genética , Osteosclerose/metabolismo , Osteosclerose/mortalidade , Osteosclerose/patologiaRESUMO
Chromatin architecture influences transcription by modulating the physical access of regulatory factors to DNA, playing fundamental roles in cell identity. Studies on dopaminergic differentiation have identified coding genes, but the relationship with non-coding genes or chromatin accessibility remains elusive. Using RNA-Seq and ATAC-Seq we profiled differentially expressed transcripts and open chromatin regions during early dopaminergic neuron differentiation. Hierarchical clustering of differentially expressed genes, resulted in 6 groups with unique characteristics. Surprisingly, the abundance of long non-coding RNAs (lncRNAs) was high in the most downregulated transcripts, and depicted positive correlations with target mRNAs. We observed that open chromatin regions decrease upon differentiation. Enrichment analyses of accessibility depict an association between open chromatin regions and specific functional pathways and gene-sets. A bioinformatic search for motifs allowed us to identify transcription factors and structural nuclear proteins that potentially regulate dopaminergic differentiation. Interestingly, we also found changes in protein and mRNA abundance of the CCCTC-binding factor, CTCF, which participates in genome organization and gene expression. Furthermore, assays demonstrated co-localization of CTCF with Polycomb-repressed chromatin marked by H3K27me3 in pluripotent cells, progressively decreasing in neural precursor cells and differentiated neurons. Our work provides a unique resource of transcription factors and regulatory elements, potentially involved in the acquisition of human dopaminergic neuron cell identity.
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Diferenciação Celular/genética , Cromatina/metabolismo , Neurônios Dopaminérgicos/citologia , Células-Tronco Embrionárias Humanas/citologia , Transcriptoma/genética , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Motivos de Nucleotídeos/genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA-Seq , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
Parkinson's disease (PD) is characterized by the progressive loss of midbrain dopaminergic neurons (DaNs) of the substantia nigra pars compacta and the decrease of dopamine in the brain. Grafting DaN differentiated from embryonic stem cells (ESCs) has been proposed as an alternative therapy for current pharmacological treatments. Intrastriatal grafting of such DaNs differentiated from mouse or human ESCs improves motor performance, restores DA release, and suppresses dopamine receptor super-sensitivity. However, a low percentage of grafted neurons survive in the brain. Glial cell line-derived neurotrophic factor (GDNF) is a strong survival factor for DaNs. GDNF has proved to be neurotrophic for DaNs in vitro and in vivo, and induces axonal sprouting and maturation. Here, we engineered mouse ESCs to constitutively produce human GDNF, to analyze DaN differentiation and the possible neuroprotection by transgenic GDNF after toxic challenges in vitro, or after grafting differentiated DaNs into the striatum of Parkinsonian rats. GDNF overexpression throughout in vitro differentiation of mouse ESCs increases the proportion of midbrain DaNs. These transgenic cells were less sensitive than control cells to 6-hydroxydopamine in vitro. After grafting control or GDNF transgenic DaNs in hemi-Parkinsonian rats, we observed significant recoveries in both pharmacological and non-pharmacological behavioral tests, as well as increased striatal DA release, indicating that DaNs are functional in the brain. The graft volume, the number of surviving neurons, the number of DaNs present in the striatum, and the proportion of DaNs in the grafts were significantly higher in rats transplanted with GDNF-expressing cells, when compared to control cells. Interestingly, no morphological alterations in the brain of rats were found after grafting of GDNF-expressing cells. This approach is novel, because previous works have use co-grafting of DaNs with other cell types that express GDNF, or viral transduction in the host tissue before or after grafting of DaNs. In conclusion, GDNF production by mouse ESCs contributes to enhanced midbrain differentiation and permits a higher number of surviving DaNs after a 6-hydroxydopamine challenge in vitro, as well as post-grafting in the lesioned striatum. These GDNF-expressing ESCs can be useful to improve neuronal survival after transplantation.
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Human skin contains keratinocytes in the epidermis. Such cells share their ectodermal origin with the central nervous system (CNS). Recent studies have demonstrated that terminally differentiated somatic cells can adopt a pluripotent state, or can directly convert its phenotype to neurons, after ectopic expression of transcription factors. In this article we tested the hypothesis that human keratinocytes can adopt neural fates after culturing them in suspension with a neural medium. Initially, keratinocytes expressed Keratins and Vimentin. After neural induction, transcriptional upregulation of NESTIN, SOX2, VIMENTIN, SOX1, and MUSASHI1 was observed, concomitant with significant increases in NESTIN detected by immunostaining. However, in vitro differentiation did not yield the expression of neuronal or astrocytic markers. We tested the differentiation potential of control and neural-induced keratinocytes by grafting them in the developing CNS of rats, through ultrasound-guided injection. For this purpose, keratinocytes were transduced with lentivirus that contained the coding sequence of green fluorescent protein. Cell sorting was employed to select cells with high fluorescence. Unexpectedly, 4 days after grafting these cells in the ventricles, both control and neural-induced cells expressed green fluorescent protein together with the neuronal proteins ßIII-Tubulin and Microtubule-Associated Protein 2. These results support the notion that in vivo environment provides appropriate signals to evaluate the neuronal differentiation potential of keratinocytes or other non-neural cell populations.
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Transplante de Tecido Encefálico/métodos , Queratinócitos/metabolismo , Animais , Humanos , RatosRESUMO
Introduction. Biological adhesives and effective topical therapeutic agents that improve wound healing are urgently required for the treatment of chronic ulcers. A biodegradable adhesive based on a carbohydrate polymer with zinc oxide (CPZO) was shown to possess anti-inflammatory activity and enhance wound healing, but its bactericidal activity was unknown.Aim. To investigate the bactericidal activity of CPZO against bacteria commonly present as infectious agents in chronic wounds.Methodology. We examined the bactericidal activity of CPZO against three biofilm-producing bacteria (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) through three strategies: bacterial suspension, biofilm disruption and in vitro wound biofilm model.Results. In suspension cultures, CPZO had direct, potent bactericidal action against S. aureus within 24 h, whereas E. coli took 7 days to be eliminated. By contrast, P. aeruginosa survived up to 14 days with CPZO. CPZO had biofilm disruption activity against clinical isolates of S. aureus in the anti-biofilm test. Finally, in the in vitro wound biofilm model, CPZO dramatically reduced the bacterial viability of S. aureus and P. aeruginosa.Conclusions. Together with its previously shown anti-inflammatory properties, the bactericidal activity of CPZO gives it the potential to be a first-line therapeutic option for chronic various ulcers and, possibly, other chronic ulcers, preventing or controlling microbial infections, and leading to the healing of such complicated chronic ulcers.
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Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Carboidratos/farmacologia , Polímeros/farmacologia , Cicatrização/efeitos dos fármacos , Óxido de Zinco/farmacologia , Infecções Bacterianas/microbiologia , Biofilmes/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana/métodosRESUMO
Two siblings from a Mexican family who carried lethal Raine syndrome are presented. A newborn term male (case 1) and his 21 gestational week brother (case 2), with a similar osteosclerotic pattern: generalized osteosclerosis, which is more evident in facial bones and cranial base. Prenatal findings at 21 weeks and histopathological features for case 2 are described. A novel combination of biallelic FAM20C pathogenic variants were detected, a maternal cytosine duplication at position 456 and a paternal deletion of a cytosine in position 474 in exon 1, which change the reading frame with a premature termination at codon 207 and 185 respectively. These changes are in concordance with a negative detection of the protein in liver and kidney as shown in case 2. Necropsy showed absence of pancreatic Langerhans Islets, which are reported here for the first time. Corpus callosum absence is added to the few reported cases of brain defects in Raine syndrome. This report shows two new FAM20C variants not described previously, and negative protein detection in the liver and the kidney. We highlight that lethal Raine syndrome is well defined as early as 21 weeks, including mineralization defects and craniofacial features. Pancreas and brain defects found here in FAM20C deficiency extend the functional spectrum of this protein to previously unknown organs.
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Anormalidades Múltiplas/genética , Caseína Quinase I/genética , Fissura Palatina/genética , Exoftalmia/genética , Proteínas da Matriz Extracelular/genética , Microcefalia/genética , Osteosclerose/genética , Anormalidades Múltiplas/metabolismo , Doenças do Desenvolvimento Ósseo , Caseína Quinase I/metabolismo , Fissura Palatina/metabolismo , Cisteína/genética , Exoftalmia/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Família , Feminino , Humanos , Recém-Nascido , Ilhotas Pancreáticas/patologia , Rim/patologia , Fígado/patologia , Masculino , Microcefalia/metabolismo , Mutação , Osteosclerose/metabolismo , Linhagem , Fenótipo , Polimorfismo Genético/genéticaRESUMO
During midbrain development, dopamine neuron differentiation occurs before birth. Epigenetic processes such as DNA methylation and demethylation as well as post-translational modification of histones occur during neurogenesis. Here, we administered histamine (HA) into the brain of E12 embryos in vivo and observed significant lower immunoreactivity of Lmx1a+ and Tyrosine Hydroxylase (TH)+ cells, with parallel decreases in the expression of early (Lmx1a, Msx1) and late (Th) midbrain dopaminergic (mDA) genes. With MeDIP assays we found that HA decreases the percentage of 5-methylcytosine of Pitx3 and Th, without changes in 5-hydroxymethylcytosine. Additionally, HA treatment caused a significant increase in the repressive epigenetic modifications H3K9me3 in Pitx3 and Th, and also more H3K27me3 marks in Th. Furthermore, HA has a long-term effect on the formation of the nigrostriatal and mesolimbic/mesocortical pathways, since it causes a significant decrease in midbrain TH immunoreactivity, as well as alterations in dopaminergic neuronal fibers, and significant lower TH-positive area in the forebrain in whole-mount stainings. These findings suggest that HA diminishes dopaminergic gene transcription by altering several epigenetic components related to DNA and histone modifications, which affects mDA neuron progression during development.
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We previously demonstrated the capacity of GAS1 (Growth Arrest Specific 1) to inhibit the growth of gliomas by blocking the GDNF-RET signaling pathway. Here, we show that a soluble form of GAS1 (tGAS1), decreases the number of viable MDA MB 231 human breast cancer cells, acting in both autocrine and paracrine manners when secreted from producing cells. Moreover, tGAS1 inhibits the growth of tumors implanted in female nu/nu mice through a RET-independent mechanism which involves interfering with the Artemin (ARTN)-GFRα3-(GDNF Family Receptor alpha 3) mediated intracellular signaling and the activation of ERK. In addition, we observed that the presence of tGAS1 reduces the vascularization of implanted tumors, by preventing the migration of endothelial cells. The present results support a potential adjuvant role for tGAS1 in the treatment of breast cancer, by detaining tumor growth and inhibiting angiogenesis.
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Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Neovascularização Patológica/prevenção & controle , Proteínas do Tecido Nervoso/metabolismo , Neoplasias de Mama Triplo Negativas/prevenção & controle , Animais , Apoptose , Western Blotting , Ciclo Celular , Proteínas de Ciclo Celular/genética , Movimento Celular , Meios de Cultivo Condicionados/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Feminino , Citometria de Fluxo , Imunofluorescência , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Nus , Proteínas do Tecido Nervoso/genética , Fosforilação , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias de Mama Triplo Negativas/irrigação sanguínea , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Transit of human neural stem cells, ReNcell CX, through the blood brain barrier (BBB) was evaluated in an in vitro model of BBB and in nude mice. The BBB model was based on rat brain microvascular endothelial cells (RBMECs) cultured on Millicell inserts bathed from the basolateral side with conditioned media (CM) from astrocytes or glioma C6 cells. Glioma C6 CM induced a significant transendothelial migration of ReNcells CX in comparison to astrocyte CM. The presence in glioma C6 CM of high amounts of HGF, VEGF, zonulin and PGE2, together with the low abundance of EGF, promoted ReNcells CX transmigration. In contrast cytokines IFN-α, TNF-α, IL-12p70, IL-1ß, IL-6, IL-8 and IL-10, as well as metalloproteinases -2 and -9 were present in equal amounts in glioma C6 and astrocyte CMs. ReNcells expressed the tight junction proteins occludin and claudins 1, 3 and 4, and the cell adhesion molecule CRTAM, while RBMECs expressed occludin, claudins 1 and 5 and CRTAM. Competing CRTAM mediated adhesion with soluble CRTAM, inhibited ReNcells CX transmigration, and at the sites of transmigration, the expression of occludin and claudin-5 diminished in RBMECs. In nude mice we found that ReNcells CX injected into systemic circulation passed the BBB and reached intracranial gliomas, which overexpressed HGF, VEGF and zonulin/prehaptoglobin 2.