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1.
Nature ; 564(7736): 359-365, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30518862

RESUMO

Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales. Here we show that this resemblance is more than skin deep. We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius. Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically distinct epidermal and dermal layers. These are underlain by insulating blubber that would have augmented streamlining, buoyancy and homeothermy. Additionally, we identify endogenous proteinaceous and lipid constituents, together with keratinocytes and branched melanophores that contain eumelanin pigment. Distributional variation of melanophores across the body suggests countershading, possibly enhanced by physiological adjustments of colour to enable photoprotection, concealment and/or thermoregulation. Convergence of ichthyosaurs with extant marine amniotes thus extends to the ultrastructural and molecular levels, reflecting the omnipresent constraints of their shared adaptation to pelagic life.


Assuntos
Evolução Biológica , Regulação da Temperatura Corporal , Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Fósseis , Homeostase , Adaptação Fisiológica , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/química , Animais , Derme/anatomia & histologia , Derme/química , Golfinhos , Epiderme/anatomia & histologia , Epiderme/química , Feminino , Queratinócitos/química , Lipídeos/análise , Masculino , Melaninas/análise , Melanóforos/química , Toninhas , Proteínas/análise
2.
Proc Natl Acad Sci U S A ; 116(8): 3018-3023, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30692253

RESUMO

Dinosaur fossils possessing integumentary appendages of various morphologies, interpreted as feathers, have greatly enhanced our understanding of the evolutionary link between birds and dinosaurs, as well as the origins of feathers and avian flight. In extant birds, the unique expression and amino acid composition of proteins in mature feathers have been shown to determine their biomechanical properties, such as hardness, resilience, and plasticity. Here, we provide molecular and ultrastructural evidence that the pennaceous feathers of the Jurassic nonavian dinosaur Anchiornis were composed of both feather ß-keratins and α-keratins. This is significant, because mature feathers in extant birds are dominated by ß-keratins, particularly in the barbs and barbules forming the vane. We confirm here that feathers were modified at both molecular and morphological levels to obtain the biomechanical properties for flight during the dinosaur-bird transition, and we show that the patterns and timing of adaptive change at the molecular level can be directly addressed in exceptionally preserved fossils in deep time.


Assuntos
Evolução Molecular , Plumas/química , Queratinas/química , beta-Queratinas/química , Animais , Aves , Dinossauros , Plumas/ultraestrutura , Fósseis , Pele/química , Pele/ultraestrutura
3.
J Environ Manage ; 318: 115499, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35717695

RESUMO

We analyzed the dynamics of pollutant emissions from wildfires in mainland China from 2001 to 2019 using MODIS fire products combined with the measurements of emission factors of different vegetation types. The biomass distribution in Mainland China has heterogeneous temporal and spatial pattern, with inter-year variations and a decreasing trend from east to west. Overall, from 2001 to 2019, biomass combustion in Mainland China reached 479.59 Tg (25.24 Tg·a-1), in which northeast, north, east, south, central, northwest, and southwest regions accounted for 20.95%, 31.14%, 8.89%, 9.06%, 3.98%, 0.33% and 25.64% of total biomass combustion, respectively. The emissions of CO, CO2, CxHy, NOx, PM2.5, TC, OC and EC were 47.30, 288.05, 12.90, 0.40, 1.43, 0.83, 0.70, and 0.12 Tg (1 Tg = 1012g), respectively. PM2.5, TC and OC emissions increased in the southwest, while all pollutant emissions declined significantly in the southern region. For particulate matter from wildfires, both the ratio of its emissions to total dust and the ratio of its concentration to atmospheric PM2.5 showed an increasing trend, implying that the relative environmental impacts of particulate emissions from wildfires may be rising. In addition, our results show that the current Chinese wildfire management has successfully reduced on average more than 80% of pollutant emissions from wildfire from 2001 to 2019 compared to the natural wildfire regime (no strict wildfire management). This research on the temporal-spatial changes of pollutant emissions from wildfires in Mainland China provides support for further exploration of wildfire impacts on regional environments, and indicates the effectiveness of Chinese current wildfire policy on the pollutant emission mitigation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Incêndios , Incêndios Florestais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Poeira , Monitoramento Ambiental , Material Particulado/análise
4.
J Anat ; 238(6): 1296-1311, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33398875

RESUMO

The ability to determine the sex of extinct dinosaurs by examining the bones they leave behind would revolutionize our understanding of their paleobiology; however, to date, definitive sex-specific skeletal traits remain elusive or controversial. Although living dinosaurs (i.e., extant birds) exhibit a sex-specific tissue called medullary bone that is unique to females, the confident identification of this tissue in non-avian archosaurs has proven a challenge. Tracing the evolution of medullary bone is complicated by existing variation of medullary bone tissues in living species; hypotheses that medullary bone structure or chemistry varied during its evolution; and a lack of studies aimed at distinguishing medullary bone from other types of endosteal tissues with which it shares microstructural and developmental characteristics, such as pathological tissues. A recent study attempted to capitalize on the molecular signature of medullary bone, which, in living birds, contains specific markers such as the sulfated glycosaminoglycan keratan sulfate, to support the proposed identification of medullary bone of a non-avian dinosaur specimen (Tyrannosaurus rex MOR 1125). Purported medullary bone samples of MOR 1125 reacted positively to histochemical analyses and the single pathological control tested (avian osteopetrosis) did not, suggesting the presence of keratan sulfate might serve to definitively discriminate these tissues for future studies. To further test these results, we sampled 20 avian bone pathologies of various etiologies (18 species), and several MB samples. Our new data universally support keratan sulfate as a reliable marker of medullary bone in birds. However, we also find that reactivity varies among pathological bone tissues, with reactivity in some pathologies indistinguishable from MB. In the current sample, some pathologies comprised of chondroid bone (often a major constituent of skeletal pathologies and developing fracture calluses in vertebrates) contain keratan sulfate. We note that beyond chemistry, chondroid bone shares many characteristics with medullary bone (fibrous matrix, numerous and large cell lacunae, potential endosteal origin, trabecular architecture) and medullary bone has even been considered by some to be a type of chondroid bone. Our results suggest that the presence of keratan sulfate is not exclusive evidence for MB, but rather must be used as one in a suite of criteria available for identifying medullary bone (and thus gravid females) in non-avian dinosaur specimens. Future studies should investigate whether there are definite chemical or microstructural differences between medullary bone and reactive chondroid bone that can discriminate these tissues.


Assuntos
Osso e Ossos/anatomia & histologia , Dinossauros/anatomia & histologia , Fósseis , Sulfato de Queratano/metabolismo , Animais , Evolução Biológica , Osso e Ossos/metabolismo , Dinossauros/metabolismo
5.
Brain Behav Immun ; 87: 890-897, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31931152

RESUMO

Parkinson's disease (PD) is one of the most significant medical and social burdens of our time. The prevalence of PD increases with age and the number of individuals diagnosed with PD is expected to double from 6.9 million in 2015 to 14.2 million in 2040. To date, no drugs can stop the ongoing neurodegeneration caused by PD due to its unclear and complex pathogenic mechanisms. It has been wildly recognized that both gut microbiota and neuro-immunity are involved in the pathology of PD. In this review, we intend to provide a comprehensive overview of current knowledge on how gut microbiota involved in immune-driven pathogenesis of PD, and its potential as a new target of dietary and/or therapeutic interventions for PD.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Humanos
6.
Biosci Biotechnol Biochem ; 84(1): 134-142, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31490096

RESUMO

Plumbagin (PLB), an alkaloid obtained from the roots of the plants of Plumbago genus, is an inhibitor of NADPH oxidase 4 (NOX4). This study aimed to investigate the beneficial effect of PLB against oxygen-glucose deprivation/reoxygenation (OGDR)-induced neuroinjury in human SH-SY5Y neuronal cultures. Our results showed that OGD/R stimulated NOX4 protein expression and reactive oxygen species (ROS) production in SH-SY5Y cells, whereas increased 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA) production, resulting in the activation of the NLRP3 inflammasome. And PLB pretreatment reduced the ROS production by regulating the expression of NOX4 and downregulated NF-κB signaling which was induced by OGDR. Furthermore, PLB inhibited OGDR induced NLRP3 inflammasome activation but not PARP1. Overall, PLB improved OGDR induced neuroinjury by inhibiting NOX4-derived ROS-activated NLRP3 inflammasome.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Glucose/deficiência , Inflamassomos/metabolismo , NADPH Oxidase 4/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Naftoquinonas/farmacologia , Neurônios/metabolismo , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/química , Plumbaginaceae/química
7.
Proteomics ; 19(16): e1800251, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31172628

RESUMO

Molecular studies have contributed greatly to our understanding of evolutionary processes that act upon virtually every aspect of living organisms. However, these studies are limited with regard to extinct organisms, particularly those from the Mesozoic because fossils pose unique challenges to molecular workflows, and because prevailing wisdom suggests no endogenous molecular components can persist into deep time. Here, the power and potential of a molecular approach to Mesozoic fossils is discussed. Molecular methods that have been applied to Mesozoic fossils-including iconic, non-avian dinosaurs- and the challenges inherent in such analyses, are compared and evaluated. Taphonomic processes resulting in the transition of living organisms from the biosphere into the fossil record are reviewed, and the possible effects of taphonomic alteration on downstream analyses that can be problematic for very old material (e.g., molecular modifications, limitations of on comparative databases) are addressed. Molecular studies applied to ancient remains are placed in historical context, and past and current studies are evaluated with respect to producing phylogenetically and/or evolutionarily significant data. Finally, some criteria for assessing the presence of endogenous biomolecules in very ancient fossil remains are suggested as a starting framework for such studies.


Assuntos
Osso e Ossos/metabolismo , Dinossauros/metabolismo , Fósseis , Proteínas/análise , Proteômica/métodos , Animais , Evolução Biológica , Osso e Ossos/anatomia & histologia , Dinossauros/anatomia & histologia , Dinossauros/classificação , Espectrometria de Massas/métodos , Paleontologia/métodos
8.
J Neurovirol ; 25(1): 127-132, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30397825

RESUMO

Vibrio vulnificus usually causes wound infection, gastroenteritis, and septicemia. However, it is a rare conditional pathogen causing meningoencephalitis. We report a case of a young, immunocompromised man presenting with severe sepsis after exposure to sea water and consumption of seafood. The patient subsequently developed meningoencephalitis, and Vibrio vulnificus was isolated from his blood culture. The sequence was confirmed by Next-generation sequencing of a sample of cerebrospinal fluid, as well as from a bacteria culture. After the pathogen was detected, the patient was treated with ceftriaxone, doxycycline, and moxifloxacin for 6 weeks, which controlled his infection. In this case, we acquired his clinical and dynamic MRI presentations, which were never reported. Physicians should consider Vibrio vulnificus infections when they see a similar clinical course, brain CT and MRI findings, susceptibility factors and recent seafood ingestion or exposure to seawater. Due to high mortality, the early diagnosis and treatment of Vibrio vulnificus infections are crucial. Next-generation sequencing was found to be useful for diagnosis.


Assuntos
Antibacterianos/uso terapêutico , Hospedeiro Imunocomprometido , Meningoencefalite/imunologia , Sepse/imunologia , Vibrio vulnificus/patogenicidade , Adulto , Ceftriaxona/uso terapêutico , Doxiciclina/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Masculino , Meningoencefalite/diagnóstico por imagem , Meningoencefalite/tratamento farmacológico , Meningoencefalite/microbiologia , Moxifloxacina/uso terapêutico , Alimentos Marinhos/microbiologia , Água do Mar/microbiologia , Sepse/diagnóstico por imagem , Sepse/tratamento farmacológico , Sepse/microbiologia , Esplenectomia , Talassemia/imunologia , Talassemia/patologia , Talassemia/cirurgia , Resultado do Tratamento , Vibrio vulnificus/efeitos dos fármacos , Vibrio vulnificus/crescimento & desenvolvimento , Vibrio vulnificus/isolamento & purificação
9.
Proc Natl Acad Sci U S A ; 113(49): E7900-E7907, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27872291

RESUMO

Microbodies associated with feathers of both nonavian dinosaurs and early birds were first identified as bacteria but have been reinterpreted as melanosomes. Whereas melanosomes in modern feathers are always surrounded by and embedded in keratin, melanosomes embedded in keratin in fossils has not been demonstrated. Here we provide multiple independent molecular analyses of both microbodies and the associated matrix recovered from feathers of a new specimen of the basal bird Eoconfuciusornis from the Early Cretaceous Jehol Biota of China. Our work represents the oldest ultrastructural and immunological recognition of avian beta-keratin from an Early Cretaceous (∼130-Ma) bird. We apply immunogold to identify protein epitopes at high resolution, by localizing antibody-antigen complexes to specific fossil ultrastructures. Retention of original keratinous proteins in the matrix surrounding electron-opaque microbodies supports their assignment as melanosomes and adds to the criteria employable to distinguish melanosomes from microbial bodies. Our work sheds new light on molecular preservation within normally labile tissues preserved in fossils.


Assuntos
Aves/anatomia & histologia , Plumas/ultraestrutura , Fósseis/ultraestrutura , Queratinas , Melanossomas , Animais , Evolução Biológica
10.
BMC Neurol ; 18(1): 174, 2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30342480

RESUMO

BACKGROUND: DNA methyltransferase 1 (EC 2.1.1.37), encoded by DNMT1 gene, is one of key enzymes in maintaining DNA methylation patterns of the human genome. It plays a crucial role in embryonic development, imprinting and genome stability, cell differentiation. The dysfunction of this group of enzymes can lead to a variety of human genetic disorders. Until now, mutations in DNMT1 have been found to be associated with two distinct phenotypes. Mutations in exon 20 of this gene leads to hereditary sensory and autonomic neuropathy type IE, and mutations in exon 21 cause autosomal dominant cerebellar ataxia, deafness and narcolepsy. CASE PRESENTATION: Here we report a novel DNMT1 mutation in a sporadic case of a Chinese patient with cerebellar ataxia, multiple motor and sensory neuropathy, hearing loss and psychiatric manifestations. Furthermore, we elucidated its pathogenic effect through molecular genetics studies and revealed that this defective DNMT1 function is responsible for the phenotypes in this individual. CONCLUSION: Our findings expand the spectrum of DNMT1-related disorders and provide a good example of precision medicine through the combination of exome sequencing and clinical testing.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/genética , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Adulto , Ataxia Cerebelar/genética , Metilação de DNA , Éxons , Feminino , Humanos , Mutação , Fenótipo
11.
J Proteome Res ; 16(2): 920-932, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28111950

RESUMO

Sequence data from biomolecules such as DNA and proteins, which provide critical information for evolutionary studies, have been assumed to be forever outside the reach of dinosaur paleontology. Proteins, which are predicted to have greater longevity than DNA, have been recovered from two nonavian dinosaurs, but these results remain controversial. For proteomic data derived from extinct Mesozoic organisms to reach their greatest potential for investigating questions of phylogeny and paleobiology, it must be shown that peptide sequences can be reliably and reproducibly obtained from fossils and that fragmentary sequences for ancient proteins can be increasingly expanded. To test the hypothesis that peptides can be repeatedly detected and validated from fossil tissues many millions of years old, we applied updated extraction methodology, high-resolution mass spectrometry, and bioinformatics analyses on a Brachylophosaurus canadensis specimen (MOR 2598) from which collagen I peptides were recovered in 2009. We recovered eight peptide sequences of collagen I: two identical to peptides recovered in 2009 and six new peptides. Phylogenetic analyses place the recovered sequences within basal archosauria. When only the new sequences are considered, B. canadensis is grouped more closely to crocodylians, but when all sequences (current and those reported in 2009) are analyzed, B. canadensis is placed more closely to basal birds. The data robustly support the hypothesis of an endogenous origin for these peptides, confirm the idea that peptides can survive in specimens tens of millions of years old, and bolster the validity of the 2009 study. Furthermore, the new data expand the coverage of B. canadensis collagen I (a 33.6% increase in collagen I alpha 1 and 116.7% in alpha 2). Finally, this study demonstrates the importance of reexamining previously studied specimens with updated methods and instrumentation, as we obtained roughly the same amount of sequence data as the previous study with substantially less sample material. Data are available via ProteomeXchange with identifier PXD005087.


Assuntos
Colágeno Tipo I/química , Dinossauros/classificação , Fósseis , Fragmentos de Peptídeos/análise , Filogenia , Proteômica/métodos , Sequência de Aminoácidos , Animais , Evolução Biológica , Osso e Ossos/química , Extinção Biológica , Paleontologia/instrumentação , Paleontologia/métodos , Proteômica/instrumentação
12.
Proc Biol Sci ; 283(1842)2016 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-28120795

RESUMO

One of the most well-recognized Cretaceous fossils is Citipati osmolskae (MPC-D 100/979), an oviraptorid dinosaur discovered in brooding position on a nest of unhatched eggs. The original description refers to a thin lens of white material extending from a manus ungual, which was proposed to represent original keratinous claw sheath that, in life, would have covered it. Here, we test the hypothesis that this exceptional morphological preservation extends to the molecular level. The fossil sheath was compared with that of extant birds, revealing similar morphology and microstructural organization. In living birds, the claw sheath consists primarily of two structural proteins; alpha-keratin, expressed in all vertebrates, and beta-keratin, found only in reptiles and birds (sauropsids). We employed antibodies raised against avian feathers, which comprise almost entirely of beta-keratin, to demonstrate that fossil tissues respond with the same specificity, though less intensity, as those from living birds. Furthermore, we show that calcium chelation greatly increased antibody reactivity, suggesting a role for calcium in the preservation of this fossil material.


Assuntos
Evolução Biológica , Dinossauros/anatomia & histologia , Casco e Garras/anatomia & histologia , Animais , Aves/anatomia & histologia , Plumas , Fósseis , Queratinas/química
13.
J Proteome Res ; 14(12): 5252-62, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26595531

RESUMO

Structures similar to blood vessels in location, morphology, flexibility, and transparency have been recovered after demineralization of multiple dinosaur cortical bone fragments from multiple specimens, some of which are as old as 80 Ma. These structures were hypothesized to be either endogenous to the bone (i.e., of vascular origin) or the result of biofilm colonizing the empty osteonal network after degradation of original organic components. Here, we test the hypothesis that these structures are endogenous and thus retain proteins in common with extant archosaur blood vessels that can be detected with high-resolution mass spectrometry and confirmed by immunofluorescence. Two lines of evidence support this hypothesis. First, peptide sequencing of Brachylophosaurus canadensis blood vessel extracts is consistent with peptides comprising extant archosaurian blood vessels and is not consistent with a bacterial, cellular slime mold, or fungal origin. Second, proteins identified by mass spectrometry can be localized to the tissues using antibodies specific to these proteins, validating their identity. Data are available via ProteomeXchange with identifier PXD001738.


Assuntos
Vasos Sanguíneos/anatomia & histologia , Vasos Sanguíneos/metabolismo , Dinossauros/anatomia & histologia , Dinossauros/metabolismo , Fósseis/anatomia & histologia , Actinas/genética , Actinas/isolamento & purificação , Sequência de Aminoácidos , Animais , Vasos Sanguíneos/microbiologia , Osso e Ossos/irrigação sanguínea , Galinhas , Dinossauros/genética , Imunofluorescência/métodos , Espectrometria de Massas , Modelos Biológicos , Dados de Sequência Molecular , Miosinas/genética , Miosinas/isolamento & purificação , Filogenia , Proteômica/métodos , Alinhamento de Sequência , Especificidade da Espécie , Struthioniformes , Tropomiosina/genética , Tropomiosina/isolamento & purificação , Tubulina (Proteína)/genética , Tubulina (Proteína)/isolamento & purificação
14.
Proc Biol Sci ; 281(1775): 20132741, 2014 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24285202

RESUMO

The persistence of original soft tissues in Mesozoic fossil bone is not explained by current chemical degradation models. We identified iron particles (goethite-αFeO(OH)) associated with soft tissues recovered from two Mesozoic dinosaurs, using transmission electron microscopy, electron energy loss spectroscopy, micro-X-ray diffraction and Fe micro-X-ray absorption near-edge structure. Iron chelators increased fossil tissue immunoreactivity to multiple antibodies dramatically, suggesting a role for iron in both preserving and masking proteins in fossil tissues. Haemoglobin (HB) increased tissue stability more than 200-fold, from approximately 3 days to more than two years at room temperature (25°C) in an ostrich blood vessel model developed to test post-mortem 'tissue fixation' by cross-linking or peroxidation. HB-induced solution hypoxia coupled with iron chelation enhances preservation as follows: HB + O2 > HB - O2 > -O2 >> +O2. The well-known O2/haeme interactions in the chemistry of life, such as respiration and bioenergetics, are complemented by O2/haeme interactions in the preservation of fossil soft tissues.


Assuntos
Fósseis , Ferro/química , Oxigênio/química , Animais , Dinossauros/anatomia & histologia , Ferro/análise , Microscopia Eletrônica de Transmissão , Struthioniformes/sangue
15.
Brain Inj ; 28(2): 227-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24456060

RESUMO

PRIMARY OBJECTIVE: To examine the neuroprotection of baicalin, a flavonoid compound derived from the dried root of Scutellaria baicalensis Georgi, on neurons. RESEARCH DESIGN: A rat PC12 cell line was used to study the neuroprotection and possible mechanisms of baicalin on H2O2-induced neuron damage. METHODS: Three anti- and one pro-apoptosis genes in PC12 cells were examined. Cell apoptosis was induced by H2O2 and apoptotic rate was obtained by flow cytometry. MTT for cell viability, immunofluorescence microscopy for promoter activity and western blot for gene expression were also employed. RESULTS: Data of MTT reduction assay and flow cytometry revealed that viability loss and apoptotic rate were reduced by pre-treatment of PC12 cells with baicalin for 24 hours. Baicalin was also found to increase SOD, GSH-Px activities and to decrease MDA level. Results from Western blot and immunofluorescence microscopy showed baicalin increased the expressions of survivin, Bcl-2 and p-STAT3 and decreased caspase-3 expression which were attenuated by AG-490. CONCLUSIONS: The results point to the possibility of the neuroprotective effects of baicalin on neuronal apoptosis induced by oxidative stress and indicate that activation of the JAK/STAT signalling pathway might involve the anti-apoptotic effect of baicalin.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Isquemia Encefálica/patologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Western Blotting , Isquemia Encefálica/tratamento farmacológico , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Imunofluorescência , Peróxido de Hidrogênio , Camundongos , Ratos
16.
J Invest Dermatol ; 143(4): 648-660.e6, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36309321

RESUMO

The transition from the proinflammatory phase to the prohealing phase in wound healing is essential for effective skin wound repair, which involves the balance of M1 and M2 polarization of wound-infiltrating macrophages. P311 plays an essential role in promoting wound closure by enhancing the biological function of epidermal stem cells, endothelial cells, and fibroblasts. Nevertheless, whether and how P311 regulates macrophage polarization remains unclear. In this study, we showed that P311 deficiency reduced the M2 polarization of macrophages, thereby attenuating the secretion of M2-like cytokines. The P311 deficiency prolonged the transition from the proinflammatory phase to the prohealing phase, accompanied by weakened angiogenesis and retarded granulation tissue formation, both of which coordinately hinder the healing of skin wounds. Mechanistically, P311 deficiency downregulated the expression of IL-4 receptor on macrophages, followed by less activation of the IL-4 receptor‒signal transducer and activator of transcription 6 signaling pathway, resulting in impaired M2 macrophage polarization. We further revealed that the mTOR signaling pathway was associated with the regulation of P311 on the expression of IL-4 receptor in macrophages. Thus, our study has highlighted the pivotal role of P311 in promoting the M2 polarization of macrophages for effective skin wound healing.


Assuntos
Células Endoteliais , Pele , Pele/lesões , Macrófagos/metabolismo , Cicatrização , Transdução de Sinais
17.
Biology (Basel) ; 11(5)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35625431

RESUMO

The exceptional preservation of feathers in the fossil record has led to a better understanding of both phylogeny and evolution. Here we address factors that may have contributed to the preservation of feathers in ancient organisms using experimental taphonomy. We show that the atmospheres of the Mesozoic, known to be elevated in both CO2 and with temperatures above present levels, may have contributed to the preservation of these soft tissues by facilitating rapid precipitation of hydroxy- or carbonate hydroxyapatite, thus outpacing natural degradative processes. Data also support that that microbial degradation was enhanced in elevated CO2, but mineral deposition was also enhanced, contributing to preservation by stabilizing the organic components of feathers.

18.
Sci Total Environ ; 841: 156772, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35724788

RESUMO

Emission of particulate matter (PM) during forest fires is a major source of air pollution and hence purification of atmospheric pollution has gained increasing importance. Trees can absorb polluting gases and fine particles by their leaves from the atmosphere and act as a sustainable air purification filter. However, the capture efficiency varies among tree species; thus exploring the ability of forest trees to capture smoke PM released during forest fires provides a basis for assessing net emissions from forest fires and the impact of smoke on forest ecosystems. In this study, the main afforestation tree species, Cunninghamia lanceolata (Lamb.) Hook, and a fire-resistant tree species, Schima superba Gardn.et Champ, in southern China were exposed to different smoke concentrations by simulating forest fire. The amount of PM per unit leaf area, absorption of nutrient element, leaf surface characteristics and antioxidant enzyme activities were determined. The main findings were: (1) The total quantity of PM captured by unit leaf area (µg·cm-2) of C. lanceolata was 28.25 ± 1.12, 30.52 ± 3.43 and 33.14 ± 3.00 in low, intermediate and high smoke concentrations, respectively. The corresponding values for S. superba was 5.96 ± 0.56, 10.09 ± 1.13 and 12.27 ± 0.39, respectively. (2) Both species had weak absorption capacity for inorganic ions in the PM. (3) The purification of smoke PM by leaves was mainly related to leaf surface roughness, where it was higher for C. lanceolata than S. superba leaves. (4) Smoke treatment positively affected the contents of chlorophyll and soluble protein as well as increased antioxidant enzyme activities. In conclusion, the findings highlight the importance of leaf structural characteristics in capturing smoke particles and C. lanceolata is better suited for purification of atmospheric smoke particles following forest fire than S. superba.


Assuntos
Poluentes Atmosféricos , Cunninghamia , Theaceae , Poluentes Atmosféricos/análise , Antioxidantes/análise , Ecossistema , Material Particulado/análise , Folhas de Planta/química , Fumaça/análise , Árvores
19.
Am J Transl Res ; 14(8): 5622-5629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105007

RESUMO

OBJECTIVE: To explore the significance of liraglutide combined with dapagliflozin or empagliflozin in the prevention of early diabetic nephropathy (DN) and its effects on renal function indices. METHODS: Three hundred patients with type 2 diabetes mellitus (T2DM) treated in our hospital from April 2019 to April 2020 were retrospectively included and divided into two groups according to different treatment regimens. Among them, 150 patients who received liraglutide alone were included in the single-drug group, and 150 patients treated with liraglutide combined with dapagliflozin or empagliflozin were included in the combination group. The baseline data and the improvement of inflammatory indices, blood glucose indices and renal function-related indices were compared between the two groups of patients. RESULTS: The baseline data such as age, body mass index, retinopathy, and course of disease had no significant difference between the two groups (P > 0.05). After treatment, the waist-to-hip ratio, total body fat percentage, total body fat mass, total body lean mass, and A/G ratio were significantly decreased in both groups (P < 0.05) compared with before treatment, and were significantly lower in the combination group than in the single-drug group (P < 0.05). The combination group had significantly lower urinary transferrin (Tf), neutrophil gelatinase-associated lipocalin (NGAL) and tumor necrosis factor (TNF)-α, insulin-like growth factor 1 (IGF-1), retinol-binding protein (RBP), homocysteine (Hcy), brain natriuretic peptide (BNP), 24 h urinary albumin excretion ratio (UAER), urine albumin to creatinine ratio (UACR) and urinary liver-type fatty acid binding protein (L-FABP) levels, and higher secretory frizzled-related protein 5 levels than the single-drug group after treatment (P < 0.05). CONCLUSION: Liraglutide combined with dapagliflozin or empagliflozin treatment can effectively reduce the levels of Tf, NGAL and TNF-α in patients with T2DM, and improve the renal function in terms of IGF-1, RBP, Hcy, BNP, UAER, UACR, L-FABP, showing high treatment safety.

20.
Oxid Med Cell Longev ; 2022: 9611362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295717

RESUMO

Atherosclerosis is a chronic inflammatory disease with a high prevalence worldwide, contributing to a series of adverse cardiovascular and cerebrovascular diseases. Periodontal disease induced by pathogenic periodontal microbiota has been well established as an independent factor of atherosclerosis. Periodontal microorganisms have been detected in atherosclerotic plaques. The high-risk microbiota dwelling in the subgingival pocket can stimulate local and systematic host immune responses and inflammatory cascade reactions through various signaling pathways, resulting in the development and progression of atherosclerosis. One often-discussed pathway is the Toll-like receptor-nuclear factor-κB (TLR-NF-κB) signaling pathway that plays a central role in the transduction of inflammatory mediators and the release of proinflammatory cytokines. This narrative review is aimed at summarizing and updating the latest literature on the association between periodontopathic microbiota and atherosclerosis and providing possible therapeutic ideas for clinicians regarding atherosclerosis prevention and treatment.


Assuntos
Aterosclerose/fisiopatologia , Inflamação/metabolismo , Microbiota/imunologia , Doenças Periodontais/microbiologia , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Fatores de Risco , Receptor 4 Toll-Like/metabolismo
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