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1.
J Chem Phys ; 160(9)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38445733

RESUMO

Helium nanodroplets ("HNDs") are widely used for forming tailor-made clusters and molecular complexes in a cold, transparent, and weakly interacting matrix. The characterization of embedded species by mass spectrometry is often complicated by the fragmentation and trapping of ions in the HNDs. Here, we systematically study fragment ion mass spectra of HND-aggregated water and oxygen clusters following their ionization by charge transfer ionization ("CTI") and Penning ionization ("PEI"). While the efficiency of PEI of embedded clusters is lower than for CTI by about factor 10, both the mean sizes of detected water clusters and the relative yields of unprotonated cluster ions are significantly larger, making PEI a "soft ionization" scheme. However, the tendency of ions to remain bound to HNDs leads to a reduced detection efficiency for large HNDs containing >104 helium atoms. These results are instrumental in determining optimal conditions for mass spectrometry and photoionization spectroscopy of molecular complexes and clusters aggregated in HNDs.

2.
Am J Respir Crit Care Med ; 207(8): 1042-1054, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36480964

RESUMO

Rationale: Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is linked to heterozygous mutations in the FOXF1 (Forkhead Box F1) gene, a key transcriptional regulator of pulmonary vascular development. There are no effective treatments for ACDMPV other than lung transplant, and new pharmacological agents activating FOXF1 signaling are urgently needed. Objectives: Identify-small molecule compounds that stimulate FOXF1 signaling. Methods: We used mass spectrometry, immunoprecipitation, and the in vitro ubiquitination assay to identify TanFe (transcellular activator of nuclear FOXF1 expression), a small-molecule compound from the nitrile group, which stabilizes the FOXF1 protein in the cell. The efficacy of TanFe was tested in mouse models of ACDMPV and acute lung injury and in human vascular organoids derived from induced pluripotent stem cells of a patient with ACDMPV. Measurements and Main Results: We identified HECTD1 as an E3 ubiquitin ligase involved in ubiquitination and degradation of the FOXF1 protein. The TanFe compound disrupted FOXF1-HECTD1 protein-protein interactions and decreased ubiquitination of the FOXF1 protein in pulmonary endothelial cells in vitro. TanFe increased protein concentrations of FOXF1 and its target genes Flk1, Flt1, and Cdh5 in LPS-injured mouse lungs, decreasing endothelial permeability and inhibiting lung inflammation. Treatment of pregnant mice with TanFe increased FOXF1 protein concentrations in lungs of Foxf1+/- embryos, stimulated neonatal lung angiogenesis, and completely prevented the mortality of Foxf1+/- mice after birth. TanFe increased angiogenesis in human vascular organoids derived from induced pluripotent stem cells of a patient with ACDMPV with FOXF1 deletion. Conclusions: TanFe is a novel activator of FOXF1, providing a new therapeutic candidate for treatment of ACDMPV and other neonatal pulmonary vascular diseases.


Assuntos
Síndrome da Persistência do Padrão de Circulação Fetal , Recém-Nascido , Humanos , Animais , Camundongos , Síndrome da Persistência do Padrão de Circulação Fetal/genética , Células Endoteliais , Pulmão/metabolismo , Fatores de Transcrição Forkhead/genética
3.
Am J Respir Cell Mol Biol ; 68(4): 430-443, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36542853

RESUMO

Mutations in the FOXF1 (forkhead box F1) gene, encoding the mesenchymal FOX (forkhead box) transcription factor, are linked to alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV), a severe congenital disorder associated with the loss of alveolar capillaries and lung hypoplasia. Although proangiogenic functions of FOXF1 have been extensively studied, the role of FOXF1 in mesenchymal-epithelial signaling during lung development remains uncharacterized. Herein, we used murine lung organoids to demonstrate that the S52F FOXF1 mutation (found in patients with ACDMPV) stimulates canonical WNT/ß-catenin signaling in type 2 alveolar epithelial cells (AEC2s), leading to increased proliferation of AEC2s and decreased differentiation of AEC2s into type 1 alveolar epithelial cells (AEC1s). Alveolar organoids containing Foxf1WT/S52F lung fibroblasts and wild-type epithelial cells grew faster on Matrigel and exhibited AEC2 hyperplasia. AEC2 hyperplasia and loss of AEC1s were found in the lungs of Foxf1WT/S52F embryos, a mouse model of ACDMPV. Activation of canonical WNT/ß-catenin signaling in AEC2s of lung organoids and Foxf1WT/S52F mice was associated with decreased expression of noncanonical WNT5A (Wnt family member 5A) ligand in lung fibroblasts. Mechanistically, FOXF1 directly activates the Wnt5a gene transcription through an evolutionarily conserved +6320/+6326 region located in the first intron of the Wnt5a gene. Site-directed mutagenesis of the +6320/+6326 region prevented the transcriptional activation of the Wnt5a enhancer by FOXF1. Treatment with exogenous WNT5A ligand inhibited the effects of the S52F FOXF1 mutation on canonical WNT/ß-catenin signaling in alveolar organoids, preventing aberrant AEC2 expansion and restoring differentiation of AEC1s. Activation of either FOXF1 or WNT5A may provide an attractive strategy to improve lung function in patients with ACDMPV.


Assuntos
Fatores de Transcrição Forkhead , Síndrome da Persistência do Padrão de Circulação Fetal , Proteína Wnt-5a , Animais , Humanos , Camundongos , beta Catenina/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Hiperplasia , Ligantes , Morfogênese , Ativação Transcricional , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo , Via de Sinalização Wnt
4.
Ann Chir Plast Esthet ; 67(2): 73-80, 2022 Mar.
Artigo em Francês | MEDLINE | ID: mdl-35183393

RESUMO

INTRODUCTION: Constriction grooves are typical abnormalities of constriction band syndrome (CBS). Treatment by complete excision and Z-plastic closure is the gold standard for release of these grooves. However, the results of these Z-plasties are often judged to be aesthetically insufficient. The hypothesis was that direct excisional surgery without Z-plasty gave better aesthetic results. The objectives of this study were (1) to evaluate the clinicaal results of the release of amniotic furrows by simple hemi-circumferential excision without resorting to Z-plasties, (2) to study the occurrence of complications, (3) to study the factors leading to complications. MATERIALS AND METHODS: All patients who had release of amniotic grooves by linear hemi-circumferential excision and closure without Z-plasties were included between 2011 and 2017. Release of complete or circumferential grooves was carried out in 2 stages. Clinical evaluation was based on parental satisfaction with the aesthetic appearance and occurrence of any complications or recurrence. RESULTS: Fourteen grooves including 8 circumferential and 6 semi-circumferential were released, in 7 patients. Average age at surgery was 9 months (3-18 months). Some patients had 1, 2 or 3 surgeries. The groove was localized in 7 cases in the leg, in 4 in the fingers and in 1 in the thigh, toes and forearm. At the last average follow-up of 25 months (12-41 months), all parents were very satisfied with the aesthetic appearance. No complications, including scarring, vascular or lymphatic disease, were noted. No recurrence was noted. CONCLUSION: Release of amniotic grooves by simple linear hemi-circumferential excision without Z-plasties is a simple, safe and effective technique. The aesthetic results are very satisfactory. LEVEL OF EVIDENCE: IV - retrospective study.


Assuntos
Síndrome de Bandas Amnióticas , Síndrome de Bandas Amnióticas/cirurgia , Cicatriz , Estética , Antebraço , Humanos , Recém-Nascido , Margens de Excisão , Estudos Retrospectivos
5.
J Physiol ; 599(3): 963-979, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33258480

RESUMO

KEY POINTS: Reduced vitamin D receptor (VDR) expression prompts skeletal muscle atrophy. Atrophy occurs through catabolic processes, namely the induction of autophagy, while anabolism remains unchanged. In response to VDR-knockdown mitochondrial function and related gene-set expression is impaired. In vitro VDR knockdown induces myogenic dysregulation occurring through impaired differentiation. These results highlight the autonomous role the VDR has within skeletal muscle mass regulation. ABSTRACT: Vitamin D deficiency is estimated to affect ∼40% of the world's population and has been associated with impaired muscle maintenance. Vitamin D exerts its actions through the vitamin D receptor (VDR), the expression of which was recently confirmed in skeletal muscle, and its down-regulation is linked to reduced muscle mass and functional decline. To identify potential mechanisms underlying muscle atrophy, we studied the impact of VDR knockdown (KD) on mature skeletal muscle in vivo, and myogenic regulation in vitro in C2C12 cells. Male Wistar rats underwent in vivo electrotransfer (IVE) to knock down the VDR in hind-limb tibialis anterior (TA) muscle for 10 days. Comprehensive metabolic and physiological analysis was undertaken to define the influence loss of the VDR on muscle fibre composition, protein synthesis, anabolic and catabolic signalling, mitochondrial phenotype and gene expression. Finally, in vitro lentiviral transfection was used to induce sustained VDR-KD in C2C12 cells to analyse myogenic regulation. Muscle VDR-KD elicited atrophy through a reduction in total protein content, resulting in lower myofibre area. Activation of autophagic processes was observed, with no effect upon muscle protein synthesis or anabolic signalling. Furthermore, RNA-sequencing analysis identified systematic down-regulation of multiple mitochondrial respiration-related protein and genesets. Finally, in vitro VDR-knockdown impaired myogenesis (cell cycling, differentiation and myotube formation). Together, these data indicate a fundamental regulatory role of the VDR in the regulation of myogenesis and muscle mass, whereby it acts to maintain muscle mitochondrial function and limit autophagy.


Assuntos
Receptores de Calcitriol , Deficiência de Vitamina D , Animais , Masculino , Fibras Musculares Esqueléticas , Músculo Esquelético/patologia , Atrofia Muscular/genética , Atrofia Muscular/patologia , Ratos , Ratos Wistar , Receptores de Calcitriol/genética , Vitamina D
6.
J Chem Phys ; 155(5): 054304, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364329

RESUMO

Linearly polarized synchrotron radiation has been used to record polarization dependent valence shell photoelectron spectra of imidazole in the photon energy range 21-100 eV. These have allowed the photoelectron angular distributions, as characterized by the anisotropy parameter ß, and the electronic state intensity branching ratios to be determined. Complementing these experimental data, theoretical photoionization partial cross sections and ß-parameters have been calculated for the outer valence shell orbitals. The assignment of the structure appearing in the experimental photoelectron spectra has been guided by vertical ionization energies and spectral intensities calculated by various theoretical methods that incorporate electron correlation and orbital relaxation. Strong orbital relaxation effects have been found for the 15a', nitrogen lone-pair orbital. The calculations also predict that configuration mixing leads to the formation of several low-lying satellite states. The vibrational structure associated with ionization out of a particular orbital has been simulated within the Franck-Condon model using harmonic vibrational modes. The adiabatic approximation appears to be valid for the X 2A″ state, with the ß-parameter for this state being independent of the level of vibrational excitation. However, for all the other outer valence ionic states, a disparity occurs between the observed and the simulated vibrational structure, and the measured ß-parameters are at variance with the behavior expected at the level of the Franck-Condon approximation. These inconsistencies suggest that the excited electronic states may be interacting vibronically such that the nuclear dynamics occur over coupled potential energy surfaces.

7.
Am J Physiol Cell Physiol ; 318(3): C536-C541, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31940245

RESUMO

Vitamin D deficiency has been linked to a reduction in skeletal muscle function and oxidative capacity; however, the mechanistic bases of these impairments are poorly understood. The biological actions of vitamin D are carried out via the binding of 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) to the vitamin D receptor (VDR). Recent evidence has linked 1α,25(OH)2D3 to the regulation of skeletal muscle mitochondrial function in vitro; however, little is known with regard to the role of the VDR in this process. To examine the regulatory role of the VDR in skeletal muscle mitochondrial function, we used lentivirus-mediated shRNA silencing of the VDR in C2C12 myoblasts (VDR-KD) and examined mitochondrial respiration and protein content compared with an shRNA scrambled control. VDR protein content was reduced by ~95% in myoblasts and myotubes (P < 0.001). VDR-KD myoblasts displayed a 30%, 30%, and 36% reduction in basal, coupled, and maximal respiration, respectively (P < 0.05). This phenotype was maintained in VDR-KD myotubes, displaying a 34%, 33%, and 48% reduction in basal, coupled, and maximal respiration (P < 0.05). Furthermore, ATP production derived from oxidative phosphorylation (ATPOx) was reduced by 20%, suggesting intrinsic impairments within the mitochondria following VDR-KD. However, despite the observed functional decrements, mitochondrial protein content, as well as markers of mitochondrial fission were unchanged. In summary, we highlight a direct role for the VDR in regulating skeletal muscle mitochondrial respiration in vitro, providing a potential mechanism as to how vitamin D deficiency might impact upon skeletal muscle oxidative capacity.


Assuntos
Mitocôndrias/fisiologia , Mioblastos/fisiologia , Receptores de Calcitriol/fisiologia , Animais , Técnicas de Silenciamento de Genes/métodos , Células HEK293 , Humanos , Camundongos , Receptores de Calcitriol/deficiência , Deficiência de Vitamina D/metabolismo
8.
Pharmacology ; 105(9-10): 541-549, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940656

RESUMO

BACKGROUND/AIMS: Inflammatory bowel disease is a chronic or remitting/relapsing intestinal inflammation, which comprises Crohn's disease and ulcerative colitis (UC). Severe UC is a life-threatening condition that requires corticosteroids (CS) as a first-line rescue therapy. Some patients are refractory to CS and may require alternative immunosuppressive therapy. Oral tacrolimus (FK506), an immunosuppressive agent, has been reported to be effective in the management of severe refractory UC, but it can cause serious adverse effects. This work aims to study the effect of tacrolimus delivered by a colon-targeted delivery system (CTDS) in a dextran sulfate sodium (DSS)-induced animal model of colitis. MATERIALS AND METHODS: We developed and evaluated an oral CTDS of tacrolimus (FK506) loaded pH-dependent polymeric microspheres, composed of Eudragit® S100 as a pH-sensitive polymer using the oil-in-water emulsion method. The physicochemical properties and drug release profiles of these microparticles in gastrointestinal tract (GIT) conditions were examined. A DSS-induced colitis rat model was used to evaluate the potential remedial and in vivo distribution of microspheres. RESULTS: The pH-microspheres prevented a burst drug release in acidic pH conditions and showed sustained release at a colonic pH. The in vivo distribution study in the rat GIT demonstrated that pH-microspheres were successfully delivered to the inflamed colon. Moreover, it also demonstrated a significant decrease of disease activity and expression of proinflammatory cytokines, such as tumor necrosis factor α, interleukin-1ß (IL-1ß), and IL-6, and minimized the histological and morphometric changes. CONCLUSION: The results confirmed the efficacy of tacrolimus (FK506) CTDs in the management of DSS-induced colitis.


Assuntos
Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Colo/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Imunossupressores/uso terapêutico , Tacrolimo/uso terapêutico , Administração Oral , Animais , Colite/induzido quimicamente , Colo/patologia , Citocinas/metabolismo , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Portadores de Fármacos/administração & dosagem , Concentração de Íons de Hidrogênio , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Masculino , Microesferas , Ácidos Polimetacrílicos/administração & dosagem , Ácidos Polimetacrílicos/farmacocinética , Ácidos Polimetacrílicos/uso terapêutico , Ratos , Ratos Wistar , Tacrolimo/administração & dosagem , Tacrolimo/farmacocinética
9.
J Basic Microbiol ; 60(2): 91-102, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31693214

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR) is a family of DNA direct repeats found in many prokaryotic genomes. It was discovered in bacteria as their (adaptive) immune system against invading viruses. Cas9 is an endonuclease enzyme linked with the CRISPR system in bacteria. Bacteria use the Cas9 enzyme to chop viral DNA sequences by unwinding it and then finding the complementary base pairs to the guide RNA. CRISPR/Cas9 is a modern and powerful molecular biology approach that is widely used in genome engineering (to activate/repress gene expression). It can be used in vivo to cause targeted genome modifications with better efficiency as compared to meganucleases, zinc-finger nucleases and transcription activator-like effector nucleases. CRISPR/Cas9 is a simple, reliable, and rapid method for causing gene alterations that open new horizons of gene editing in a variety of living organisms, including humans, for the treatment of several diseases. In this short review, we explored the basic mechanisms underlying its working principles along with some of its current applications in a number of diverse fields.


Assuntos
Bactérias/genética , Sistemas CRISPR-Cas , Edição de Genes , Biologia Molecular/métodos
10.
J Appl Microbiol ; 126(6): 1708-1721, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30882965

RESUMO

AIMS: The current study was aimed to evaluate the beneficial effects and bioremediation potential of a Cd-tolerant bacterial strain, Serratia sp. CP-13, on the physiological and biochemical functions of Linum usitatissimum L., under Cd stress. METHODS AND RESULTS: The bacterial strain was isolated from the wastewater collection point of Chakera, Faisalabad, Pakistan, as this place contains industrial wastewater of the Faisalabad region. The Serratia sp. CP-13, identified through 16S rRNA gene sequence analysis, exhibited a significant phyto-beneficial potential in terms of in vitro inorganic phosphate solubilization, indole-3-acetic acid production and 1-aminocyclopropane-1-carboxylic acid deaminase activity. Effects of Serratia sp. CP-13 inoculation on L. usitatissimum were evaluated by growing the plants in CdCl2 (0, 5 or 10 mg kg-1 dry soil)-spiked soil. Without inoculation of Serratia sp. CP-13, Cd stress significantly reduced the plant biomass as well as the quantity of proteins and photosynthetic pigments due to enhanced H2 O2 , malondialdehyde (MDA) contents and impaired nutrient homeostasis. Subsequently, Serratia sp. CP-13 increased the plant fresh and dry biomass, plant antioxidation capacity, whereas it decreased the lipid peroxidation under Cd stress. In parallel, Serratia sp. inoculation assisted the Cd-stressed plants to maintain an optimum level of nutrients (K, Ca, P, Mg, Fe and Mn). CONCLUSIONS: The isolated bacterial strain (Serratia sp. CP-13) when applied to Cd-stressed L. usitatissimum inhibited the Cd uptake, reduced Cd-induced lipid peroxidation, maintained the optimum level of nutrients and thereby, enhanced L. usitatissimum growth. The analysis of bio-concentration and translocation factor revealed that L. usitatissimum with Serratia sp. CP-13 inoculation sequestered Cd in plant rhizospheric zone. SIGNIFICANCE AND IMPACT OF THE STUDY: Serratia sp. CP-13 inoculation is a potential candidate for the development of low Cd-accumulating linseed and could be used for phytostabilization of Cd-contaminated rhizosphere/soil colloids.


Assuntos
Cádmio/metabolismo , Linho/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/fisiologia , Serratia/fisiologia , Poluentes do Solo/metabolismo , Antioxidantes/metabolismo , Biodegradação Ambiental , Biomassa , Cádmio/toxicidade , Linho/efeitos dos fármacos , Linho/metabolismo , Nutrientes/metabolismo , Poluentes do Solo/toxicidade , Águas Residuárias/microbiologia
11.
J Basic Microbiol ; 58(1): 3-16, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29131357

RESUMO

Zika virus is one of the emerging viruses and is of significant threat to human health globally. It is a mosquito borne flavivirus similar to dengue, yellow fever, and West Nile viruses. It was reported about 5 decades ago and then it spreads to different parts of the world. Large outbreaks were reported on Yap Islands in 2007. Now it has gained wide attention globally by health communities. Major vector for virus transmission is Aedes aegypti mosquito. ZIKV infection is mostly asymptomatic but it is also responsible to cause mild influenza like illness to serious manifestations. There is no specific anti-viral treatment is available for ZIKV infection. The virus disseminates very fast due to which it possesses a serious threat especially in those areas where there is lack of specific immunity against virus. Little knowledge is available on its transmission and pathogenicity. Although virus was discovered years ago but its genomic structure is not clearly understood yet. In this review we focus on the current knowledge of epidemiology of ZIKV, its transmission, its structural biology, different aspects of diagnosis and diagnostic challenges as well as highlighted appropriates antiviral drugs and vaccines regarding treatment.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissão , Zika virus/genética , África/epidemiologia , América/epidemiologia , Animais , Ásia/epidemiologia , Surtos de Doenças , Variação Genética , Humanos , Filogenia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Vacinas Virais/administração & dosagem , Zika virus/química , Zika virus/imunologia , Zika virus/patogenicidade , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/tratamento farmacológico
12.
Hum Genet ; 135(3): 299-307, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26767831

RESUMO

Although epidemiological evidence suggests a human genetic basis of pulmonary tuberculosis (PTB) susceptibility, the identification of specific genes and alleles influencing PTB risk has proven to be difficult. Previous genome-wide association (GWA) studies have identified only three novel loci with modest effect sizes in sub-Saharan African and Russian populations. We performed a GWA study of 550,352 autosomal SNPs in a family-based discovery Moroccan sample (on the full population and on the subset with PTB diagnosis at <25 years), which identified 143 SNPs with p < 1 × 10(-4). The replication study in an independent case/control sample identified four SNPs displaying a p < 0.01 implicating the same risk allele. In the combined sample including 556 PTB subjects and 650 controls these four SNPs showed suggestive association (2 × 10(-6) < p < 4 × 10(-5)): rs358793 and rs17590261 were intergenic, while rs6786408 and rs916943 were located in introns of FOXP1 and AGMO, respectively. Both genes are involved in the function of macrophages, which are the site of latency and reactivation of Mycobacterium tuberculosis. The most significant finding (p = 2 × 10(-6)) was obtained for the AGMO SNP in an early (<25 years) age-at-onset subset, confirming the importance of considering age-at-onset to decipher the genetic basis of PTB. Although only suggestive, these findings highlight several avenues for future research in the human genetics of PTB.


Assuntos
Estudo de Associação Genômica Ampla , Tuberculose Pulmonar/genética , Adolescente , Adulto , Idade de Início , Idoso , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Loci Gênicos , Técnicas de Genotipagem , Humanos , Lactente , Íntrons , Masculino , Pessoa de Meia-Idade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Marrocos , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reprodutibilidade dos Testes , Fatores de Risco , Tuberculose Pulmonar/microbiologia , Adulto Jovem
14.
Langmuir ; 32(23): 5899-908, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27181278

RESUMO

We present a simple synthesis of iron oxide nanotubes, grown under very mild conditions from a solution containing Fe(II) and Fe(III), on rod-shaped tobacco mosaic virus templates. Their well-defined shape and surface chemistry suggest that these robust bionanoparticles are a versatile platform for synthesis of small, thin mineral tubes, which was achieved efficiently. Various characterization tools were used to explore the iron oxide in detail: Electron microscopy (SEM, TEM), magnetometry (SQUID-VSM), diffraction (XRD, TEM-SAED), electron spectroscopies (EELS, EDX, XPS), and X-ray absorption (XANES with EXAFS analysis). They allowed determination of the structure, crystallinity, magnetic properties, and composition of the tubes. The protein surface of the viral templates was crucial to nucleate iron oxide, exhibiting analogies to biomineralization in natural compartments such as ferritin cages.


Assuntos
Compostos Férricos/química , Nanotubos/química , Vírus do Mosaico do Tabaco/química , Nanotubos/ultraestrutura , Vírus do Mosaico do Tabaco/ultraestrutura
15.
Environ Monit Assess ; 188(4): 230, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26992902

RESUMO

In the present study, milk samples including raw and ultra-high temperature (UHT) processed milk were analyzed for pesticide residue levels, including five pesticides, viz chloripyrifos, endosulfan (α and ß), profenofos and bifenthrin by gas chromatography microelectron capture detector (GC-µECD) after extraction by QuEChERS method. Further confirmation of the pesticide residue was done by GC-MS. The pesticide residual level in raw and UHT milk samples (n = 70) was determined in the range of 0.1-30 µg L(-1). All UHT processed milk samples contain pesticide residues within permissible limit set by the World Health Organization (WHO); however, among raw milk samples, chloripyrifos (12 %), α (24 %), and ß (14 %) endosulfan were found above the maximum residue limit (MRL). The estimated daily intake (EDI) of these four pesticide residues were also calculated as 1.32, 16.16, 5.30, 10.20, and 9.93 µg kg(-1) body weight for chloripyrifos, endosulfan α, profenofos, endosulfan ß, and bifenthrin, respectively. It is concluded that the raw milk samples showed higher prevalence of pesticide residues as compared to UHT processed milk. Graphical abstract Determination of pesticide residues in dairy milk by GC-µECD after QuEChERS extraction method.


Assuntos
Poluentes Ambientais/análise , Leite/química , Resíduos de Praguicidas/análise , Animais , Fracionamento Químico/métodos , Cromatografia Gasosa/métodos , Endossulfano/análise , Monitoramento Ambiental , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Praguicidas/análise , Piretrinas
16.
Ann Dermatol Venereol ; 143(12): 836-840, 2016 Dec.
Artigo em Francês | MEDLINE | ID: mdl-27496274

RESUMO

BACKGROUND: Pansclerotic morphea is a poorly described but extremely debilitating variant of localized scleroderma. We report a case with a rapidly fatal outcome in an 11-year-old girl. PATIENTS AND METHODS: An 11-year-old girl with a 2-year history of morphea presented at our institution in April 2012. The sclerosis had started on her trunk and progressed rapidly to involve her entire skin. Initial treatment with corticosteroids was ineffective and she presented extremely painful ulcerations of the lower limbs. The outcome was rapidly fatal, in early 2014, due to cachexia and sepsis after two amputations and several failed treatments including methotrexate. DISCUSSION: Pansclerotic morphea is characterized by rapidly progressing sclerosis involving the entire skin, trophic cutaneous ulcers, painful contraction and limited joint mobility. The prognosis is poor since the disease has an incapacitating and potentially fatal outcome. No reliably effective treatment has yet been established. CONCLUSION: Our case highlights the clinical characteristics of this uncommon form of localized scleroderma, the extremely severe prognosis, and the therapeutic challenge involved.


Assuntos
Esclerodermia Localizada/complicações , Caquexia/etiologia , Criança , Evolução Fatal , Feminino , Humanos , Úlcera da Perna/etiologia , Sepse/etiologia
17.
Adv Dent Res ; 27(1): 10-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26101335

RESUMO

This review aims to determine the prevalence and severity of oral health diseases in the Africa and Middle East region (AMER). The profile of oral diseases is not homogeneous across the AMER. There are large disparities between groups. Reliable data are scarce. The prevalence and severity of oral diseases appear to be increasing in the African region, as does associated morbidity. There are substantial differences in inequalities in oral health. Dental caries prevalence is less severe in most African countries than in developed countries, but the high rate of untreated caries reflects the limited resources available and difficulties of access and affordability to essential oral health care services. The prevalence of gingival inflammation is very high in all age groups in several African countries. The prevalence of maxillofacial trauma has increased in many countries, with a wide variation of the incidence and high prevalence of traumatic dental injuries in primary and permanent teeth. Orofacial clefts are among the most common birth defects. Annual incidence of oral cancer is estimated as 25 cases per 100,000 people in Africa. Noma is a major public health problem for the Middle East and North African (MENA) region. Data about human immunodeficiency virus/AIDS are limited, particularly in the MENA region. According to the World Health Organization Regional Committee for Africa report, some fundamental key basic knowledge gaps need to be underlined. They include inequalities in oral health, low priority for oral health, lack of adequate funding, inadequate dental student training, obstacles to medical and dental research, and poor databases. There are very few effective public prevention and oral health promotion programs in the AMER. Universal health coverage is not achievable without scientific research on the effectiveness of health promotion interventions.


Assuntos
Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde , Doenças da Boca/epidemiologia , Doenças da Boca/prevenção & controle , África/epidemiologia , Política de Saúde , Prioridades em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Incidência , Oriente Médio/epidemiologia , Prevalência , Fatores de Risco , Índice de Gravidade de Doença
18.
Indian J Nephrol ; 34(2): 169-171, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680998

RESUMO

Nephrotic syndrome (NS) is one of the common presentations of kidney diseases both in children and adults. NS patients, particularly those with membranous nephropathy, have increased risk of thromboembolic events. Heparin and vitamin K antagonists (VKAs) continue to be commonly used as prophylactic and therapeutic agents, given the experience of use of these agents in NS and nonrenal indications of anticoagulation. The use of direct oral anticoagulants (DOACs) in NS is reported in some case series, conference abstracts, and a few small studies. We report our experience of using DOACs in 11 patients of NS with severe hypoalbuminemia. Out of 11, one patient required change of anticoagulation from DOACs to VKA and the rest of them did well with DOACs. There were no bleeding episodes in our study. We suggest larger studies to be carried out to better understand the use of these agents in NS.

19.
bioRxiv ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38915647

RESUMO

Human organoid model systems have changed the landscape of developmental biology and basic science. They serve as a great tool for human specific interrogation. In order to advance our organoid technology, we aimed to test the compatibility of a piezoelectric material with organoid generation, because it will create a new platform with the potential for sensing and actuating organoids in physiologically relevant ways. We differentiated human pluripotent stem cells into spheroids following the traditional human intestinal organoid (HIO) protocol atop a piezoelectric nanofiber scaffold. We observed that exposure to the biocompatible piezoelectric nanofibers promoted spheroid morphology three days sooner than with the conventional methodology. At day 28 of culture, HIOs grown on the scaffold appeared similar. Both groups were readily transplantable and developed well-organized laminated structures. Graft sizes between groups were similar. Upon characterizing the tissue further, we found no detrimental effects of the piezoelectric nanofibers on intestinal patterning or maturation. Furthermore, to test the practical feasibility of the material, HIOs were also matured on the nanofiber scaffolds and treated with ultrasound, which lead to increased cellular proliferation which is critical for organoid development and tissue maintenance. This study establishes a proof of concept for integrating piezoelectric materials as a customizable platform for on-demand electrical stimulation of cells using remote ultrasonic waveforms in regenerative medicine.

20.
EMBO Mol Med ; 16(5): 1063-1090, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38589650

RESUMO

Cancer cells re-program normal lung endothelial cells (EC) into tumor-associated endothelial cells (TEC) that form leaky vessels supporting carcinogenesis. Transcriptional regulators that control the reprogramming of EC into TEC are poorly understood. We identified Forkhead box F1 (FOXF1) as a critical regulator of EC-to-TEC transition. FOXF1 was highly expressed in normal lung vasculature but was decreased in TEC within non-small cell lung cancers (NSCLC). Low FOXF1 correlated with poor overall survival of NSCLC patients. In mice, endothelial-specific deletion of FOXF1 decreased pericyte coverage, increased vessel permeability and hypoxia, and promoted lung tumor growth and metastasis. Endothelial-specific overexpression of FOXF1 normalized tumor vessels and inhibited the progression of lung cancer. FOXF1 deficiency decreased Wnt/ß-catenin signaling in TECs through direct transcriptional activation of Fzd4. Restoring FZD4 expression in FOXF1-deficient TECs through endothelial-specific nanoparticle delivery of Fzd4 cDNA rescued Wnt/ß-catenin signaling in TECs, normalized tumor vessels and inhibited the progression of lung cancer. Altogether, FOXF1 increases tumor vessel stability, and inhibits lung cancer progression by stimulating FZD4/Wnt/ß-catenin signaling in TECs. Nanoparticle delivery of FZD4 cDNA has promise for future therapies in NSCLC.


Assuntos
Células Endoteliais , Fatores de Transcrição Forkhead , Receptores Frizzled , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Progressão da Doença , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Receptores Frizzled/metabolismo , Receptores Frizzled/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Neovascularização Patológica/genética , Via de Sinalização Wnt
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