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1.
Proc Natl Acad Sci U S A ; 121(6): e2220392121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38305758

RESUMO

Germline colonization by retroviruses results in the formation of endogenous retroviruses (ERVs). Most colonization's occurred millions of years ago. However, in the Australo-Papuan region (Australia and New Guinea), several recent germline colonization events have been discovered. The Wallace Line separates much of Southeast Asia from the Australo-Papuan region restricting faunal and pathogen dispersion. West of the Wallace Line, gibbon ape leukemia viruses (GALVs) have been isolated from captive gibbons. Two microbat species from China appear to have been infected naturally. East of Wallace's Line, the woolly monkey virus (a GALV) and the closely related koala retrovirus (KoRV) have been detected in eutherians and marsupials in the Australo-Papuan region, often vertically transmitted. The detected vertically transmitted GALV-like viruses in Australo-Papuan fauna compared to sporadic horizontal transmission in Southeast Asia and China suggest the GALV-KoRV clade originates in the former region and further models of early-stage genome colonization may be found. We screened 278 samples, seven bat and one rodent family endemic to the Australo-Papuan region and bat and rodent species found on both sides of the Wallace Line. We identified two rodents (Melomys) from Australia and Papua New Guinea and no bat species harboring GALV-like retroviruses. Melomys leucogaster from New Guinea harbored a genomically complete replication-competent retrovirus with a shared integration site among individuals. The integration was only present in some individuals of the species indicating this retrovirus is at the earliest stages of germline colonization of the Melomys genome, providing a new small wild mammal model of early-stage genome colonization.


Assuntos
Quirópteros , Retrovirus Endógenos , Gammaretrovirus , Marsupiais , Animais , Vírus da Leucemia do Macaco Gibão/genética , Nova Guiné , Gammaretrovirus/genética , Murinae/genética , Marsupiais/genética , Células Germinativas
2.
New Phytol ; 241(1): 298-313, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37882365

RESUMO

In leaves of C4 plants, the reactions of photosynthesis become restricted between two compartments. Typically, this allows accumulation of C4 acids in mesophyll (M) cells and subsequent decarboxylation in the bundle sheath (BS). In C4 grasses, proliferation of plasmodesmata between these cell types is thought to increase cell-to-cell connectivity to allow efficient metabolite movement. However, it is not known whether C4 dicotyledons also show this enhanced plasmodesmal connectivity and so whether this is a general requirement for C4 photosynthesis is not clear. How M and BS cells in C4 leaves become highly connected is also not known. We investigated these questions using 3D- and 2D-electron microscopy on the C4 dicotyledon Gynandropsis gynandra as well as phylogenetically close C3 relatives. The M-BS interface of C4 G. gynandra showed higher plasmodesmal frequency compared with closely related C3 species. Formation of these plasmodesmata was induced by light. Pharmacological agents that perturbed photosynthesis reduced the number of plasmodesmata, but this inhibitory effect could be reversed by the provision of exogenous sucrose. We conclude that enhanced formation of plasmodesmata between M and BS cells is wired to the induction of photosynthesis in C4 G. gynandra.


Assuntos
Magnoliopsida , Células do Mesofilo , Células do Mesofilo/metabolismo , Plasmodesmos/metabolismo , Folhas de Planta/metabolismo , Fotossíntese , Poaceae
3.
PLoS Biol ; 19(4): e3001166, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33826607

RESUMO

Neural stem cell (NSC) transplantation induces recovery in animal models of central nervous system (CNS) diseases. Although the replacement of lost endogenous cells was originally proposed as the primary healing mechanism of NSC grafts, it is now clear that transplanted NSCs operate via multiple mechanisms, including the horizontal exchange of therapeutic cargoes to host cells via extracellular vesicles (EVs). EVs are membrane particles trafficking nucleic acids, proteins, metabolites and metabolic enzymes, lipids, and entire organelles. However, the function and the contribution of these cargoes to the broad therapeutic effects of NSCs are yet to be fully understood. Mitochondrial dysfunction is an established feature of several inflammatory and degenerative CNS disorders, most of which are potentially treatable with exogenous stem cell therapeutics. Herein, we investigated the hypothesis that NSCs release and traffic functional mitochondria via EVs to restore mitochondrial function in target cells. Untargeted proteomics revealed a significant enrichment of mitochondrial proteins spontaneously released by NSCs in EVs. Morphological and functional analyses confirmed the presence of ultrastructurally intact mitochondria within EVs with conserved membrane potential and respiration. We found that the transfer of these mitochondria from EVs to mtDNA-deficient L929 Rho0 cells rescued mitochondrial function and increased Rho0 cell survival. Furthermore, the incorporation of mitochondria from EVs into inflammatory mononuclear phagocytes restored normal mitochondrial dynamics and cellular metabolism and reduced the expression of pro-inflammatory markers in target cells. When transplanted in an animal model of multiple sclerosis, exogenous NSCs actively transferred mitochondria to mononuclear phagocytes and induced a significant amelioration of clinical deficits. Our data provide the first evidence that NSCs deliver functional mitochondria to target cells via EVs, paving the way for the development of novel (a)cellular approaches aimed at restoring mitochondrial dysfunction not only in multiple sclerosis, but also in degenerative neurological diseases.


Assuntos
Vesículas Extracelulares/metabolismo , Mitocôndrias/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/ultraestrutura
4.
Int J Mol Sci ; 25(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38203350

RESUMO

Male reproduction depends on hormonally driven behaviors and numerous genes for testis development and spermatogenesis. Neuroplastin-deficient (Nptn-/-) male mice cannot sire offspring. By immunohistochemistry, we characterized neuroplastin expression in the testis. Breeding, mating behavior, hormonal regulation, testicular development, and spermatogenesis were analyzed in cell-type specific neuroplastin mutant mice. Leydig, Sertoli, peritubular myoid, and germ cells express Np, but spermatogenesis and sperm number are not affected in Nptn-/- males. Neuroplastin lack from CNS neurons or restricted to spermatogonia or Sertoli cells permitted reproduction. Normal luteinizing hormone (LH) and follicle-stimulating hormone (FSH) blood levels in Nptn-/- males support undisturbed hormonal regulation in the brain. However, Nptn-/- males lack mounting behavior accompanied by low testosterone blood levels. Testosterone rise from juvenile to adult blood levels is absent in Nptn-/- males. LH-receptor stimulation raising intracellular Ca2+ in Leydig cells triggers testosterone production. Reduced Plasma Membrane Ca2+ ATPase 1 (PMCA1) in Nptn-/- Leydig cells suggests that Nptn-/- Leydig cells produce sufficient testosterone for testis and sperm development, but a lack of PMCA-Np complexes prevents the increase from reaching adult blood levels. Behavioral immaturity with low testosterone blood levels underlies infertility of Nptn-/- males, revealing that Np is essential for reproduction.


Assuntos
Infertilidade , Sêmen , Masculino , Animais , Camundongos , Fertilidade/genética , Reprodução , Testosterona , Glicoproteínas de Membrana
5.
Biol Reprod ; 106(4): 775-791, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35020825

RESUMO

As a major spermadhesin first found in the seminal plasma (SP) of boars, AWN is described to fulfil a variety of reproduction related tasks. Although being the best investigated boar spermadhesin, information about its interaction with membranes is inconsistent. In this regard, previous reports locate AWN either inside or on the surface of sperm cells and at different regions, depending on the method and antibody used. Here, we localize native AWN (natAWN) in/on epididymal, ejaculated, capacitated, and acrosome-reacted boar sperm using epifluorescence and electron microscopy as well as an analysis of potential lipid-binding partners of natAWN and recombinant AWN (recAWN). By applying a custom-made anti-AWN antibody, localization of AWN in the equatorial segment (EQS) of ejaculated, capacitated, and acrosome-reacted boar sperm was discovered. Electron microscopy showed that AWN is localized both on the sperm surface and on the cytoplasmic side of the plasma membrane and in close vicinity to the nuclear and both acrosomal membranes of sperm. Analysis of epididymal sperm indicated migration of AWN from the retral postacrosomal part to the EQS during the epididymal passage. In contrast to hypotheses claiming a specific association of AWN to phosphatidylethanolamine (PE) and in line with our previous study describing an interaction with phosphatidic acid (PA), the current results show a rather electrostatically driven binding mechanism of AWN to negative lipids. In conclusion, this work provides new insights into the arrangement of AWN in the EQS, which suggest a possible role in sperm-oocyte fusion.


Assuntos
Proteínas de Transporte , Proteínas de Plasma Seminal , Animais , Proteínas de Transporte/metabolismo , Masculino , Sêmen/metabolismo , Proteínas de Plasma Seminal/metabolismo , Espermatozoides/metabolismo , Suínos
6.
PLoS Comput Biol ; 17(7): e1009109, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34264927

RESUMO

Sperm migration in the female genital tract controls sperm selection and, therefore, reproductive success as male gametes are conditioned for fertilization while their number is dramatically reduced. Mechanisms underlying sperm migration are mostly unknown, since in vivo investigations are mostly unfeasible for ethical or practical reasons. By presenting a spatio-temporal model of the mammalian female genital tract combined with agent-based description of sperm motion and interaction as well as parameterizing it with bovine data, we offer an alternative possibility for studying sperm migration in silico. The model incorporates genital tract geometry as well as biophysical principles of sperm motion observed in vitro such as positive rheotaxis and thigmotaxis. This model for sperm migration from vagina to oviducts was successfully tested against in vivo data from literature. We found that physical sperm characteristics such as velocity and directional stability as well as sperm-fluid interactions and wall alignment are critical for success, i.e. sperms reaching the oviducts. Therefore, we propose that these identified sperm parameters should be considered in detail for conditioning sperm in artificial selection procedures since the natural processes are normally bypassed in reproductive in vitro technologies. The tremendous impact of mucus flow to support sperm accumulation in the oviduct highlights the importance of a species-specific optimum time window for artificial insemination regarding ovulation. Predictions from our extendable in silico experimental system will improve assisted reproduction in humans, endangered species, and livestock.


Assuntos
Tubas Uterinas , Reprodução/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Animais , Bovinos , Biologia Computacional , Simulação por Computador , Tubas Uterinas/anatomia & histologia , Tubas Uterinas/fisiologia , Feminino , Humanos , Masculino
7.
BMC Infect Dis ; 22(1): 539, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35692037

RESUMO

BACKGROUND: Acute myocardial injury is associated with poor prognosis in respiratory tract infections. We aimed to highlight the differences in prevalence of myocardial injury and its impact on prognosis in patients with COVID-19 compared to those with seasonal influenza. METHODS: This was a single-center prospective cohort study with a historical control group. 300 age-/sex-matched SARS-CoV-2 and seasonal influenza positive patients were enrolled. Myocardial injury was assessed by electrocardiogram (ECG), transthoracic echocardiography and biomarkers including high-sensitivity troponin-I. All patients were followed-up for 30 days after enrollment for all-cause mortalitiy, admission to the intensive care unit (ICU) and mechanical ventilation. RESULTS: Right ventricular distress was more common in COVID-19 whereas pathological ECG findings and impaired left ventricular function were more prevalent among influenza patients. COVID-19 patients suffered from a higher percentage of hypertension and dyslipidaemia. Contrary to COVID-19, pericardial effusion at admission was associated with poor outcome in the influenza group. Severe course of disease and respiratory failure resulted in significantly higher rates of ICU treatment and mechanical ventilation in COVID-19 patients. Although distribution of myocardial injury was similar, significantly fewer cardiac catheterizations were performed in COVID-19 patients. However, number of cardiac catheterizations was low in both groups. Finally, 30-day mortality was significantly higher in COVID-19 compared to influenza patients. CONCLUSIONS: In adults requiring hospitalization due to COVID-19 or seasonal influenza, cardiovascular risk factors and signs of myocardial distress differ significantly. Furthermore, cardiovascular comorbidities may impair prognosis in COVID-19 patients to a higher degree than in their influenza counterparts.


Assuntos
COVID-19 , Influenza Humana , Adulto , Humanos , Influenza Humana/complicações , Influenza Humana/epidemiologia , Prognóstico , Estudos Prospectivos , SARS-CoV-2 , Estações do Ano
8.
BMC Plant Biol ; 21(1): 258, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34134628

RESUMO

BACKGROUND: Dionysia tapetodes, a small cushion-forming mountainous evergreen in the Primulaceae, possesses a vast surface-covering of long silky fibres forming the characteristic "woolly" farina. This contrasts with some related Primula which instead form a fine powder. Farina is formed by specialized cellular factories, a type of glandular trichome, but the precise composition of the fibres and how it exits the cell is poorly understood. Here, using a combination of cell biology (electron and light microscopy) and analytical chemical techniques, we present the principal chemical components of the wool and its mechanism of exit from the glandular trichome. RESULTS: We show the woolly farina consists of micron-diameter fibres formed from a mixture of flavone and substituted flavone derivatives. This contrasts with the powdery farina, consisting almost entirely of flavone. The woolly farina in D. tapetodes is extruded through specific sites at the surface of the trichome's glandular head cell, characterised by a small complete gap in the plasma membrane, cell wall and cuticle and forming a tight seal between the fibre and hole. The data is consistent with formation and thread elongation occurring from within the cell. CONCLUSIONS: Our results suggest the composition of the D. tapetodes farina dictates its formation as wool rather than powder, consistent with a model of thread integrity relying on intermolecular H-bonding. Glandular trichomes produce multiple wool fibres by concentrating and maintaining their extrusion at specific sites at the cell cortex of the head cell. As the wool is extensive across the plant, there may be associated selection pressures attributed to living at high altitudes.


Assuntos
Flavonas/análise , Primulaceae/ultraestrutura , Tricomas/ultraestrutura , Microscopia , Microscopia Eletrônica , Primulaceae/química
9.
Eur J Clin Invest ; 51(7): e13539, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33729579

RESUMO

BACKGROUND: Gremlin-1 is a cystine knot protein and is expressed in organs developing fibrosis. Transient ischaemia leads to myocardial fibrosis, a major determinant of impaired myocardial function. MATERIALS AND METHODS: Expression of Gremlin-1 was investigated in infarcted myocardium by real-time PCR, Western blot analysis, histological and immunohistochemistry staining. We further elaborated the colocalization of Gremlin-1 and TGF-ß proteins by confocal microscopy and co-immunoprecipitation experiments. The interaction between Gremlin-1 and TGF-ß was analysed by photon correlation spectroscopy. Gremlin-1 modulation of the TGF-ß-dependent collagen I synthesis in fibroblasts was investigated using ELISA and immunohistochemistry experiments. The effect of prolonged administration of recombinant Gremlin-1 on myocardial function following ischaemia/reperfusion was accessed by echocardiography and immunohistochemistry. RESULTS: Gremlin-1 is expressed in myocardial tissue and infiltrating cells after transient myocardial ischaemia (P < .05). Gremlin-1 colocalizes with the pro-fibrotic cytokine transforming growth factor-ß (TGF-ß) expressed in fibroblasts and inflammatory cell infiltrates (P < .05). Gremlin-1 reduces TGF-ß-induced collagen production of myocardial fibroblasts by approximately 20% (P < .05). We found that Gremlin-1 binds with high affinity to TGF-ß (KD  = 54 nmol/L) as evidenced by photon correlation spectroscopy and co-immunoprecipitation. intravenous administration of m Gremlin-1-Fc, but not of equivalent amount of Fc control, significantly reduced infarct size by approximately 20%. In the m Gremlin-1-Fc group, infarct area was reduced by up to 30% in comparison with mice treated with Fc control (I/LV: 4.8 ± 1.2% vs 6.0 ± 1.2% P < .05; I/AaR: 15.2 ± 1.5% vs 21.1 ± 5%, P < .05). CONCLUSIONS: The present data disclose Gremlin-1 as an antagonist of TGF-ß and presume a role for Gremlin-1/TGF-ß interaction in myocardial remodelling following myocardial ischaemia.


Assuntos
Fibroblastos/metabolismo , Coração/fisiopatologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/genética , Miocárdio/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Colágeno Tipo I/metabolismo , Ecocardiografia , Células Endoteliais/metabolismo , Fibroblastos/efeitos dos fármacos , Fibrose , Coração/diagnóstico por imagem , Coração/efeitos dos fármacos , Humanos , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Camundongos , Microscopia Confocal , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Proteínas Recombinantes , Fator de Crescimento Transformador beta/efeitos dos fármacos , Remodelação Ventricular/genética
10.
Psychopathology ; 54(3): 150-158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951644

RESUMO

INTRODUCTION: Research on body aspects in depression primarily focuses on somatic complaints, while phenomenologists emphasize the pre-reflective bodily experience of depression as relevant for the psychopathology of it. Despite this increasing acknowledgement of the subjective body's impact on depression, empirically, it remains rarely studied. METHODS: Relying on the psychotherapy method of Focusing (Gendlin, 1982), interviews were developed, which enable participants with depression to get in contact with pre-reflective bodily experiences through turning inward, attentively observing all bodily feelings that arise, and finding symbolizations for these feelings. RESULTS: In 501 codings of the conducted interviews, the theme of passivity emerged on a continuum ranging from inhibition of drive to lack of drive. It can be split into 5 components (heaviness, emptiness, paralysis, blockage, and alienation), which were felt in the head or the whole body. Moreover, participants reported active, pressuring feelings in the chest and stomach areas, which were associated with specific emotions in some participants. DISCUSSION: In conclusion, through focusing, participants were able to take note of their pre-reflective bodily feelings and described feelings of passivity, active, pressuring feelings, and an ambivalence between these two parts. Results support the notion that depression is associated with specific pre-reflective bodily experiences and lay a foundation for future research.


Assuntos
Depressão/psicologia , Emoções/fisiologia , Entrevista Psicológica/métodos , Psicoterapia/métodos , Adulto , Afeto , Feminino , Humanos , Masculino
11.
Int J Mol Sci ; 22(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34681838

RESUMO

Platelets play a significant role in atherothrombosis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is critically involved in the regulation of LDL metabolism and interacts with platelet function. The effect of PCSK9 in platelet function is poorly understood. The authors of this article sought to characterize platelets as a major source of PCSK9 and PCSK9's role in atherothrombosis. In a large cohort of patients with coronary artery disease (CAD), platelet count, platelet reactivity, and platelet-derived PCSK9 release were analyzed. The role of platelet PCSK9 on platelet and monocyte function was investigated in vitro. Platelet count and hyper-reactivity correlated with plasma LDL in CAD. The circulating platelets express on their surface and release substantial amounts of PCSK9. Release of PCSK9 augmented platelet-dependent thrombosis, monocyte migration, and differentiation into macrophages/foam cells. Platelets and PCSK9 accumulated in tissue derived from atherosclerotic carotid arteries in areas of macrophages. PCSK9 inhibition reduced platelet activation and platelet-dependent thrombo-inflammation. The authors identified platelets as a source of PCSK9 in CAD, which may have an impact on LDL metabolism. Furthermore, platelet-derived PCSK9 contributes to atherothrombosis, and inhibition of PCSK9 attenuates thrombo-inflammation, which may contribute to the reported beneficial clinical effects.


Assuntos
Aterosclerose/metabolismo , Plaquetas/fisiologia , Doença da Artéria Coronariana/metabolismo , Lipoproteínas LDL/metabolismo , Pró-Proteína Convertase 9/fisiologia , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas/estatística & dados numéricos , Trombose/metabolismo
12.
J Environ Manage ; 298: 113530, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34411800

RESUMO

Mono- and co-sorption of the three antibiotics i.e., norfloxacin (NOR), sulfamerazine (SMR) and oxytetracycline (OTC), to raw and NH4+-modified cassava waste biochar added to aqueous solutions were investigated. The NH4+-modified biochar showed higher sorption affinity for both NOR and SMR than the raw biochar, while the raw biochar showed higher sorption affinity for OTC than the modified biochar. The highest sorption to both biochars in both the mono- and competitive sorption systems was found for OTC followed by NOR and SMR. Sorption equilibrium in all systems analyzed was reached within 15 h. Electrostatic interactions among the ionic antibiotics in the multicomponent solution increased NOR and SMR sorption to both biochars. Antibiotics' mono- and co-sorption to biochars decreased with increasing solution pH. The co-sorption of NOR and SMR to the two biochars was regulated by π-π electron-donor-acceptor (EDA) interactions; besides, electrostatic interactions and Hydrogen (H-) bonding played an important part. Cation bridging might have been a potential mechanism to contribute to SMR sorption to the raw biochar, and OTC sorption to the NH4+-modified biochar. These observations will improve our understanding of the simultaneous removal of multiple antibiotics from water or wastewater.


Assuntos
Compostos de Amônio , Manihot , Adsorção , Antibacterianos , Carvão Vegetal , Água
13.
New Phytol ; 227(3): 810-823, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32249430

RESUMO

Green algae expressing a carbon-concentrating mechanism (CCM) are usually associated with a Rubisco-containing micro-compartment, the pyrenoid. A link between the small subunit (SSU) of Rubisco and pyrenoid formation in Chlamydomonas reinhardtii has previously suggested that specific RbcS residues could explain pyrenoid occurrence in green algae. A phylogeny of RbcS was used to compare the protein sequence and CCM distribution across the green algae and positive selection in RbcS was estimated. For six streptophyte algae, Rubisco catalytic properties, affinity for CO2 uptake (K0.5 ), carbon isotope discrimination (δ13 C) and pyrenoid morphology were compared. The length of the ßA-ßB loop in RbcS provided a phylogenetic marker discriminating chlorophyte from streptophyte green algae. Rubisco kinetic properties in streptophyte algae have responded to the extent of inducible CCM activity, as indicated by changes in inorganic carbon uptake affinity, δ13 C and pyrenoid ultrastructure between high and low CO2 conditions for growth. We conclude that the Rubisco catalytic properties found in streptophyte algae have coevolved and reflect the strength of any CCM or degree of pyrenoid leakiness, and limitations to inorganic carbon in the aquatic habitat, whereas Rubisco in extant land plants reflects more recent selective pressures associated with improved diffusive supply of the terrestrial environment.


Assuntos
Chlamydomonas reinhardtii , Clorófitas , Carbono , Dióxido de Carbono , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Clorófitas/metabolismo , Fotossíntese , Filogenia , Ribulose-Bifosfato Carboxilase/metabolismo
14.
Environ Res ; 184: 109324, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32163771

RESUMO

Biochar adsorbent was produced by pyrolyzing traditional Chinese medicinal herb residue at 300, 500 and 750 °C (referred to as biochar-300, biochar-500 and biochar-750). Basic physical and chemical analyses, Fourier transform infrared spectroscopy (FT-IR), and thermodynamic analyses were performed to elucidate adsorption and properties of biochar. Biochar adsorption capacity of herbicide metolochlor, as measured by batch-type adsorption experiments by Freundlich constant Kf (mg1-n Ln kg-1), followed the order: biochar-750 > biochar-300 > biochar-500. Thermodynamic analysis suggested that adsorption of metolachlor on biochar was a spontaneous process. The adsorption isotherm for the biochar produced at the highest pyrolysis temperature was characteristic for adsorption process driven by a high surface area of biochar (85.30 m2 g-1), while the adsorption process for the biochar produced at the lowest temperature was controlled by its higher content of organic matter (39.06%) and abundant functional groups. The FT-IR spectra also showed that the biochar prepared at the lowest temperature had the highest number of surface groups. In general, pore-filling induced by the large surface area of the biochar was the dominant adsorption mechanism. When the H/C value was >0.5, the adsorption mechanism of biochar was dominated by surface chemical bond, while pore-filling played a major role when the H/C value was <0.5.


Assuntos
Carvão Vegetal , Herbicidas , Acetamidas , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Reprod Domest Anim ; 55 Suppl 2: 55-60, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31876343

RESUMO

Cryobanking of gametes in combination with artificial insemination is an essential option to support conservation programmes for endangered and threatened species. About two-thirds of the felid species are classified as 'near threatened', 'vulnerable' or 'endangered' (www.cites.org), and mostly, epididymal sperm are collected from euthanized or castrated male felids and cryopreserved. However, epididymal compared with ejaculated and cryopreserved compared with fresh sperm have a limited potential to fertilize if vaginal non-surgical insemination is applied in feline species. Missing or highly diluted seminal fluid in epididymal and cryopreserved sperm, as well as a potential interference of extender ingredients with the natural interactive properties of sperm in the female genital tract is discussed as potential drawback which hampers a proper sperm transit and fertilization besides the limited longevity of cryopreserved feline sperm. Individual components in seminal fluid as well as cryoextenders may adversely alter sperm properties and have a different impact on fertility and preservation success. The identification and investigation of beneficial as well as detrimental components is a precondition to deduce options for improving the process of cryopreservation in felids, particularly, if only epididymal sperm are available.


Assuntos
Criopreservação/veterinária , Felidae/fisiologia , Preservação do Sêmen/veterinária , Animais , Conservação dos Recursos Naturais/métodos , Criopreservação/métodos , Espécies em Perigo de Extinção , Epididimo/citologia , Feminino , Fertilidade , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/métodos , Espermatozoides/fisiologia
16.
Cell Physiol Biochem ; 52(3): 435-438, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873819

RESUMO

BACKGROUND/AIMS: Tachycardiomyopathy (TCM) is a largely reversible form of non-ischemic heart failure. The underlying mechanism are, however, still today poorly understood. Recent data indicate distinct changes in mitochondrial distribution in these patients, compared to other non-ischemic cardiomyopathies.This study investigated underlying mechanisms in mitochondrial dynamics in endomyocardial biopsy samples (EMB) from patients with TCM and compared them to patients with dilated cardiomyopathy (DCM), which show similar clinical features. METHODS: Focused mRNA analyses were performed on routinely obtained paraffinfixed EMB specimen from patients fulfilling TCM diagnosis criteria, as well as patients with DCM to elucidate regulatory changes in mitochondrial fusion, fission and mitophagy. RESULTS: In patients with TCM we were able to identify mRNA of Mitofusin 1 and 2, two effector proteins regulating mitochondrial fusion, to be strongly upregulated compared to patients with DCM. Conclusively, we did not find differences in the mRNA expression of mitochondrial fission regulators including DRP1, Fis1, MFF, MiD49, and MiD51. Furthermore, we did not find significant changes in PINK1 expression, an important mediator for mitochondrial autophagy. CONCLUSION: The mRNA upregulation of Mitofusin 1 and 2 provides first insight into the complex changes of mitochondrial dynamics in cardiomyocytes of patients with reversible heart failure due to TCM.


Assuntos
Cardiomiopatia Dilatada/genética , GTP Fosfo-Hidrolases/genética , Mitocôndrias/genética , Dinâmica Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas Mitocondriais/genética , RNA Mensageiro/genética , Biópsia , Cardiomiopatia Dilatada/classificação , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/fisiopatologia , Dinaminas , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Frequência Cardíaca/fisiologia , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Mensageiro/metabolismo
17.
Reproduction ; 157(1): 77-85, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30394706

RESUMO

Biochemical properties of polyunsaturated fatty acids (PUFAs) are fundamental to sperm movements. Amongst all adjustments operated during epididymal maturation, sperm membrane lipid composition is remodelled. Specifically, the proportion of PUFAs usually increases from the caput towards the cauda epididymidis. In mammals, PUFAs are predominantly acquired through the diet, which can consequently impact male fertility. We aimed at analysing to what extent n-6 and n-3 PUFAs are incorporated into sperm in the Seba's short-tailed bat (Carollia perspicillata), and at demonstrating the effect of the sperm fatty acid composition on sperm mobility. We therefore provided food varying in fatty acid composition to males of C. perspicillata and measured the fatty acid composition and mobility traits in spermatozoa collected from the caput and cauda epididymides. We found that n-6 and n-3 PUFAs and saturated fatty acids were significantly related to sperm velocity but not to the proportion of progressive sperm (i.e. motility). Concomitant to an increase in sperm velocity, the level of fatty acid saturation increased from the caput to the cauda epididymidis, while the proportion of PUFAs remained similar along the epididymis. A reduction in n-6 PUFAs counterbalanced an increase in n-3 PUFAs. The food treatments did not affect the sperm fatty acid composition. Our results suggest that a precise endogenous control rather than dietary effects determines sperm fatty acid composition in C. perspicillata.


Assuntos
Quirópteros , Ácidos Graxos/análise , Maturação do Esperma/fisiologia , Espermatozoides/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Quirópteros/metabolismo , Gorduras Insaturadas na Dieta/farmacologia , Epididimo/citologia , Epididimo/fisiologia , Ácidos Graxos/metabolismo , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/fisiologia , Masculino , Análise do Sêmen/veterinária , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo
18.
Acta Oncol ; 58(7): 1069-1076, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30971150

RESUMO

Introduction: Patient preferences are often not discussed in treatment decisions in oncology. We introduced an online values clarification method (VCM) to help newly diagnosed rectal cancer patients participate in shared decision making about short-course preoperative radiotherapy. Material and Methods: We offered a link to the VCM to a subset of consecutive patients before the pretreatment consultation with the radiation oncologist. Consultations were audiotaped and coded for expressions of patient preferences. Patients were asked to complete pre- and post-consultation questionnaires. Questionnaires assessed values clarity, decision regret and presence and impact of fecal incontinence and sexual problems. Results: Of 135 patients who had their consultation audiotaped and completed questionnaires, 35 received and accessed the VCM-link. Patients in the VCM-group slightly more often expressed preferences during consultations. Questionnaire data showed that patients in the VCM-group did not differ in how clear their values were, but experienced lower regret and less impact of treatment harms at 6 months follow-up; differences were non-significant but in the same direction at 12 months. Discussion: This is the first study to assess the effect of an adaptive conjoint analysis-based VCM on actual patient-clinician communication, and long-term decision regret and impact of treatment harms. Being explicitly invited to think about treatment benefits and harms seems to help patients to live with treatment consequences.


Assuntos
Tomada de Decisão Clínica/métodos , Tomada de Decisão Compartilhada , Participação do Paciente , Preferência do Paciente/psicologia , Neoplasias Retais/terapia , Idoso , Colectomia , Emoções , Incontinência Fecal/etiologia , Incontinência Fecal/psicologia , Feminino , Humanos , Masculino , Memória Episódica , Pessoa de Meia-Idade , Relações Médico-Paciente , Qualidade de Vida , Lesões por Radiação/etiologia , Lesões por Radiação/psicologia , Radio-Oncologistas , Radioterapia Adjuvante/efeitos adversos , Encaminhamento e Consulta , Disfunções Sexuais Psicogênicas/etiologia , Disfunções Sexuais Psicogênicas/psicologia , Inquéritos e Questionários
19.
Somatosens Mot Res ; 35(3-4): 192-198, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30461318

RESUMO

BACKGROUND: Many researchers have tried to investigate pain by studying brain responses. One method used to investigate pain-related brain responses is continuous electroencephalography (EEG). The objective of the current study is to add on to our understanding of EEG responses during pain, by differentiation between EEG patterns indicative of (i) the noxious stimulus intensity and (ii) the subjective pain sensation. METHODS: EEG was recorded during the administration of tonic experimental pain, consisting of six minutes of contact heat applied to the leg via a thermode. Two stimuli above pain threshold, one at pain threshold and two non-painful stimuli were administered. Thirty-six healthy participants provided a subjective pain rating during thermal stimulation. Relative EEG power was calculated for the frequency bands alpha1, alpha2, beta1, beta2, delta, and theta. RESULTS: Whereas EEG activity could not be predicted by stimulus intensity (except in one frequency band), subjective pain sensation could significantly predict differences in EEG activity in several frequency bands. An increase in the subjective pain sensation was associated with a decrease in alpha2, beta1, beta2 as well as in theta activity across the midline electrodes. CONCLUSION: The subjective experience of pain seems to capture unique variance in EEG activity above and beyond what is captured by noxious stimulus intensity.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Hiperalgesia/fisiopatologia , Percepção da Dor/fisiologia , Limiar da Dor/fisiologia , Dor/fisiopatologia , Adulto , Feminino , Temperatura Alta/efeitos adversos , Humanos , Masculino , Medição da Dor , Estimulação Física/efeitos adversos , Análise de Regressão , Adulto Jovem
20.
J Biol Chem ; 291(45): 23578-23588, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27634046

RESUMO

Glutathione peroxidase 4 (GPX4) and arachidonic acid 15-lipoxygenase (ALOX15) are antagonizing enzymes in the metabolism of hydroperoxy lipids. In spermatoid cells and/or in the male reproductive system both enzymes are apparently expressed, and GPX4 serves as anti-oxidative enzyme but also as a structural protein. In this study we explored whether germ line inactivation of the Alox15 gene might rescue male subfertility induced by heterozygous expression of catalytically silent Gpx4. To address this question we employed Gpx4 knock-in mice expressing the Sec46Ala-Gpx4 mutant, in which the catalytic selenocysteine was replaced by a redox inactive alanine. Because homozygous Gpx4 knock-in mice (Sec46Ala-Gpx4+/+) are not viable we created heterozygous animals (Sec46Ala-Gpx4+/-) and crossed them with Alox15 knock-out mice (Alox15-/-). Male Sec46Ala-Gpx4+/- mice, but not their female littermates, were subfertile. Sperm extracted from the epididymal cauda showed strongly impaired motility characteristics and severe structural midpiece alterations (swollen mitochondria, intramitochondrial vacuoles, disordered mitochondrial capsule). Despite these structural alterations, they exhibited similar respiration characteristics than wild-type sperm. When Sec46Ala-Gpx4+/- mice were crossed with Alox15-deficient animals, the resulting males (Sec46Ala-Gpx4+/-+Alox15-/-) showed normalized fertility, and sperm motility was reimproved to wild-type levels. Taken together these data suggest that systemic inactivation of the Alox15 gene normalizes the reduced fertility of male Sec46Ala-Gpx4+/- mice by improving the motility of their sperm. If these data can be confirmed in humans, ALOX15 inhibitors might counteract male infertility related to GPX4 deficiency.


Assuntos
Araquidonato 12-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/genética , Glutationa Peroxidase/genética , Infertilidade Masculina/genética , Animais , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Regulação para Baixo , Feminino , Técnicas de Introdução de Genes , Glutationa Peroxidase/metabolismo , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mutação , Estresse Oxidativo , Oxigênio/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Motilidade dos Espermatozoides , Espermatozoides/citologia , Espermatozoides/metabolismo , Espermatozoides/patologia
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