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1.
Dalton Trans ; 53(16): 7163-7174, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38573306

RESUMO

Reactions between 1,2-di(tetrazol-2-yl)ethane (ebtz), 1,6-di(tetrazol-2-yl)hexane (hbtz) or 1,1'-di(tetrazol-1-yl)methane (1ditz) and Fe(BF4)2 in the presence of adiponitrile (ADN), glutaronitrile (GLN) or suberonitrile (SUN) resulted in the formation of coordination polymers [Fe(µ-ebtz)2(µ-ADN)](BF4)2 (1), [Fe(µ-hbtz)2(µ-ADN)](BF4)2 (2), [Fe(µ-1ditz)2(GLN)2](BF4)2·GLN (3) and [Fe(µ-1ditz)2(µ-SUN)](BF4)2·SUN (4). It was established that the application of dinitriles allows an increase in the dimensionality of the ebtz and hbtz based systems while maintaining the structure of the polymeric units characteristic of previously studied mononitrile based analogues. In 3 and 4, regardless of the type of dinitrile coligand, the motif of 2D polymeric layers constituted by 1ditz molecules remains preserved. However, the dimensionality of 1ditz based networks is governed by the coordination modes of dinitriles. 3, based on a shorter molecule of glutaronitrile, crystallizes as a two-dimensional (2D) coordination polymer. In this compound, dinitriles coordinate monodentately or play the role of guest molecules. The substitution of glutaronitrile with suberonitrile enables the bridging of neighboring polymeric layers, resulting in a 3D network. The intentional selection of bis(tetrazoles) and dinitriles as building blocks has led, as expected, to obtaining systems with the structure of the first coordination sphere consisting of four tetrazole rings and two axially coordinated nitrile molecules. It created the conditions required for the occurrence of thermally induced spin crossover. Magnetic measurements and single crystal X-ray diffraction studies were used for the characterization of the spin crossover properties of 1-4.

2.
Chemistry ; 30(4): e202302887, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37906679

RESUMO

Cooling [Fe(bbtr)3 ](BF4 )2 (bbtr=1,4-di(1,2,3-triazol-1-yl)butane) triggers very slow spin crossover below 80 K (T1/2 ↓ =76 K). The spin crossover (SCO) is accompanied by a hysteresis loop (T1/2 ↑ =89 K). In contrast to isostructural perchlorate analogue [Fe(bbtr)3 ](ClO4 )2 in which spin crossover during cooling is preceded by phase transition at TPT =126 K in tetrafluoroborate phase transition does not occur to the beginning of spin crossover (80 K). Studies of mixed crystals [Fe(bbtr)3 ](BF4 )2(1-x) (ClO4 )2x (0.5≤x≤0.9) showed that a phase transition precedes spin crossover, however, for x≅0.46 intersection of T1/2 (x) and TPT (x) dependencies takes place. The application of pressure of 1 GPa shifts the spin crossover in [Fe(bbtr)3 ](BF4 )2 to a temperature above 270 K. High-pressure studies of neat tetrafluoroborate and perchlorate, as well as mixed crystals [Fe(bbtr)3 ](BF4 )2(1-x) (ClO4 )2x (0.1≤x≤0.9), revealed that at 295 K P1/2 value changes linearly with x indicating similar mechanism of spin crossover under elevated pressure in all systems under investigation. Variable pressure single crystal X-ray diffraction studies confirmed that in contrast to thermally induced spin crossover undergoing differently in tetrafluoroborate and perchlorate an application of high pressure removes this differentiation leading to a similar mechanism depending at first on start spin crossover and then P-3→P-1 phase transition occurs. In this report we have shown that 2D coordination polymer [Fe(bbtr)3 ](BF4 )2 (bbtr=1,4-di(1,2,3-triazol-1-yl)butane) treated to date as spin crossover silent shows thermally induced spin crossover phenomenon. Spin crossover in tetrafluoroborate is extremely slow. Determination of the spin crossover curve required carrying measurement in the settle mode-cooling from 85 to 70 K took about 600 h (average velocity of change of temperature ca. 0.0004 K/min).

3.
Carbohydr Res ; 533: 108941, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37717483

RESUMO

New fluorinated and nonfluorinated sugar alkenylphosphonates were obtained. In all cases 1,2;5,6-di-O-isopropylidene-α-d-glucofuranose was used as the starting material. The synthesis of alkenylphosphonates was based on Horner-Wadsworth-Emmons olefination. The process led to products with E-stereochemistry exclusively or predominately.


Assuntos
Açúcares , Açúcares/síntese química
4.
Beilstein J Org Chem ; 19: 434-439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37091732

RESUMO

In this paper, we present the solvolysis reaction of dipeptide analogues of fluorinated aminophosphonates with simultaneous quantitative deprotection of the amino group. To the best of our knowledge, this work is the first reported example of the application of fluorinated aminophosphonates in cathepsin C inhibition studies. The new molecules show moderate inhibition of the cathepsin C enzyme, which opens the door to consider them as potential therapeutic agents. Overall, our findings provide a new avenue for the development of fluorinated aminophosphonate-based inhibitors.

5.
Org Biomol Chem ; 21(6): 1095-1120, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36632995

RESUMO

Selective introduction of a double bond motif into a multifunctional organic compound is always a big challenge. The Horner-Wadsworth-Emmons reaction is one of the most reliable, simple, and stereoselective olefination methods, widely used in organic chemistry. To the best of our knowledge, no review article on the application of HWE reaction in the synthesis of fluoroorganic compounds with direct biological interest has been published in recent years. The importance of the HWE reaction should be emphasised due to its simplicity and stereoselectivity. Under mild conditions and in one step, valuable compounds can be obtained. The HWE reaction is primarily a great tool in the synthesis of fluoroolefins that are, among others, peptide bond mimetics. Therefore, it can serve as an indispensable approach to access peptide bioisosteres and, consequently, analogues of numerous enzyme inhibitors. The protocol may be utilized to obtain florinated vinylphosphonate, vinylsulfone or sulfonate derivatives, which exhibit biological activity. In this review article, we would like to summarize the HWE reaction output of the last 12 years (since 2010).

6.
Molecules ; 27(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080169

RESUMO

Herein, we present the application of fluorinated carbohydrate-derived building blocks for α-hydroxy ß-fluoro/ß-trifluoromethyl and unsaturated phosphonates synthesis. Pudovik and Horner-Wadsworth-Emmons reactions were applied to achieve this goal. The proposed pathway of the key reactions is supported by the experimental results, as well as quantum chemical calculations. The structure of the products was established by spectroscopic (1D, 2D NMR) and spectrometric (MS) techniques. Based on our data received, we claim that the progress of the Pudovik and HWE reactions is significantly influenced by the acidic protons present in the molecules as assessed by pKa values of the reagent.


Assuntos
Organofosfonatos , Carboidratos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Organofosfonatos/química , Estereoisomerismo
7.
Org Biomol Chem ; 20(28): 5615-5623, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35796647

RESUMO

Herein, we would like to present deoxyfluorinating reagents such as DAST and PyFluor and their successful use as tools for selective modification of γ-amino-α-hydroxyphosphonates. Depending on the deoxyfluorinating reagent applied, an intramolecular cyclization leading to phosphonates containing the 1,3-oxazinan-2-one moiety or direct nucleophilic deoxyfluorination yielding the α-fluorinated derivatives of γ-aminophosphonates was observed. The obtained compounds may be used as precursors in the preparation of medicinally important compounds e.g., dipeptide analogues or scaffolds containing the 1,3-oxazinan-2-one group.


Assuntos
Organofosfonatos , Ciclização , Indicadores e Reagentes , Estrutura Molecular , Organofosfonatos/química
8.
Neuroscience ; 499: 64-103, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35853563

RESUMO

Dopamine facilitates approach to reward via its actions on dopamine receptors in the nucleus accumbens. For example, blocking either D1 or D2 dopamine receptors in the accumbens reduces the proportion of reward-predictive cues to which rats respond with cued approach. Recent evidence indicates that accumbens dopamine also promotes wakefulness and arousal, but the relationship between dopamine's roles in arousal and reward seeking remains unexplored. Here, we show that the ability of systemic or intra-accumbens injections of the D1 antagonist SCH23390 to reduce cued approach to reward depends on the animal's state of arousal. Handling the animal, a manipulation known to increase arousal, was sufficient to reverse the behavioral effects of the antagonist. In addition, SCH23390 reduced spontaneous locomotion and increased time spent in sleep postures, both consistent with reduced arousal, but also increased time spent immobile in postures inconsistent with sleep. In contrast, the ability of the D2 antagonist haloperidol to reduce cued approach was not reversible by handling. Haloperidol reduced spontaneous locomotion but did not increase sleep postures, instead increasing immobility in non-sleep postures. We place these results in the context of the extensive literature on dopamine's contributions to behavior, and propose the arousal-motor hypothesis. This novel synthesis, which proposes that two main functions of dopamine are to promote arousal and facilitate motor behavior, accounts both for our findings and many previous behavioral observations that have led to disparate and conflicting conclusions.


Assuntos
Antagonistas de Dopamina , Dopamina , Animais , Nível de Alerta , Dopamina/fisiologia , Antagonistas de Dopamina/farmacologia , Haloperidol/farmacologia , Núcleo Accumbens , Ratos , Receptores de Dopamina D1 , Recompensa
9.
Front Neurosci ; 15: 631328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305511

RESUMO

Despite the fact that there is a growing awareness to the callosal connections between hemispheres the two hemispheres of the brain are commonly treated as independent structures when peripheral or cortical manipulations are applied to one of them. The contralateral hemisphere is often used as a within-animal control of plastic changes induced onto the other side of the brain. This ensures uniform conditions for producing experimental and control data, but it may overlook possible interhemispheric interactions. In this paper we provide, for the first time, direct proof that cortical, experience-dependent plasticity is not a unilateral, independent process. We mapped metabolic brain activity in rats with 2-[14C] deoxyglucose (2DG) following experience-dependent plasticity induction after a month of unilateral (left), partial whiskers deprivation (only row B was left). This resulted in ∼45% widening of the cortical sensory representation of the spared whiskers in the right, contralateral barrel field (BF). We show that the width of 2DG visualized representation is less than 20% when only contralateral stimulation of the spared row of whiskers is applied in immobilized animals. This means that cortical map remodeling, which is induced by experience-dependent plasticity mechanisms, depends partially on the contralateral hemisphere. The response, which is observed by 2DG brain mapping in the partially deprived BF after standard synchronous bilateral whiskers stimulation, is therefore the outcome of at least two separately activated plasticity mechanisms. A focus on the integrated nature of cortical plasticity, which is the outcome of the emergent interactions between deprived and non-deprived areas in both hemispheres may have important implications for learning and rehabilitation. There is also a clear implication that there is nothing like "control hemisphere" since any plastic changes in one hemisphere have to have influence on functioning of the opposite one.

10.
ACS Appl Mater Interfaces ; 13(7): 8049-8059, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570931

RESUMO

Label-free optical detection of biomolecules is currently limited by a lack of specificity rather than sensitivity. To exploit the much more characteristic refractive index dispersion in the mid-infrared (IR) regime, we have engineered three-dimensional IR-resonant silicon micropillar arrays (Si-MPAs) for protein sensing. By exploiting the unique hierarchical nano- and microstructured design of these Si-MPAs attained by CMOS-compatible silicon-based microfabrication processes, we achieved an optimized interrogation of surface protein binding. Based on spatially resolved surface functionalization, we demonstrate controlled three-dimensional interfacing of mammalian cells with Si-MPAs. Spatially controlled surface functionalization for site-specific protein immobilization enabled efficient targeting of soluble and membrane proteins into sensing hotspots directly from cells cultured on Si-MPAs. Protein binding to Si-MPA hotspots at submonolayer level was unambiguously detected by conventional Fourier transform IR spectroscopy. The compatibility with cost-effective CMOS-based microfabrication techniques readily allows integration of this novel IR transducer into fully fledged bioanalytical microdevices for selective and sensitive protein sensing.


Assuntos
Técnicas Biossensoriais , Proteínas de Fluorescência Verde/isolamento & purificação , Análise Serial de Proteínas , Silício/química , Campos Eletromagnéticos , Proteínas de Fluorescência Verde/química , Células HeLa , Humanos , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
11.
Chemistry ; 26(63): 14419-14434, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-32678463

RESUMO

Reaction of 1,2-di(tetrazol-2-yl)ethane (ebtz) with Fe(BF4 )2 ⋅6 H2 O in different nitriles yields one-dimensional coordination polymers [Fe(ebtz)2 (RCN)2 ](BF4 )2 ⋅nRCN (n=2 for R=CH3 (1) and n=0 for R=C2 H5 (2) C3 H7 (3), C3 H5 (4), CH2 Cl (5)) exhibiting spin crossover (SCO). SCO in 1 and 3-5 is complete and occurs above 160 K. In 2, it is shifted to lower temperatures and is accompanied by wide hysteresis (T1/2 ↓ =78 K, T1/2 ↑ =123 K) and proceeds extremely slowly. Isothermal (80 K) time-resolved single-crystal X-ray diffraction studies revealed a complex nature for the HS→LS transition in 2. An initial, slow stage is associated with shrinkage of polymeric chains and with reduction of volume at 77 % (in relation to the difference between cell volumes VHS -VLS ) whereas only 16 % of iron(II) ions change spin state. In the second stage, an abrupt SCO occurs, associated with breathing of the crystal lattice along the direction of the Fe-nitrile bonds, while the nitriles reorient. HS→LS switching triggered by light (808 nm) reveals the coupling of spin state and nitrile orientation. The importance of this coupling was confirmed by studies of [Fe(ebtz)2 (C2 H5 CN/C3 H7 CN)2 ](BF4 )2 mixed crystals (2 a, 2 b), showing a shift of T1/2 to higher values and narrowing of the hysteresis loop concomitant with an increase of the fraction of butyronitrile. This increase reduces the capability of nitrile molecules to reorient. Density functional theory (DFT) studies of models of 1-5 suggest a particular possibility of 2 to adopt a low (140-145°) value of its Fe-N-C(propionitrile) angle.

12.
Dalton Trans ; 49(28): 9811-9819, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32633296

RESUMO

1,4-Di(1-ethyl-1,2,3-triazol-5-yl)butane (bbtre) was prepared by lithiation of 1-ethyl-1,2,3-triazole, followed by alkylation with 1,4-dibromobutane. The ligand bbtre forms a three-dimensional network with Fe(ii), [Fe(bbtre)3](ClO4)2·2CH3CN, that exhibits thermally induced spin crossover (SCO). A change of temperature or change of spin state results in various types of structural transformation, leading to different structures that are stable in strictly defined temperature ranges. As a result, there are three spin crossover transitions arranged via two different paths. Thus, cooling below 280 K involves a HT(HS) → LT(HS) (HT, high temperature structure; LT, low temperature structure; HS, high spin) phase transition (PT), which is associated with conformational changes of the bbtre molecules and with deformation of the polymeric skeleton. In the LT phase incomplete and reversible LT(HS) ⇄ LT(HS/LS) spin crossover occurs (LS, low spin). In contrast, rapid cooling (of a sample not previously thermally treated) allows the HT(HS) → LT(HS) phase transition to be avoided, and so complete HT(HS) → HT1(LS) SCO occurs. This means that the PT plays the role of a switch, which allows a choice of one of two ways in which the SCO will proceed. After rapid cooling, further heating to 150 K and subsequent cooling results in a reversible HT1(HS) ⇄ HT1(LS) spin crossover (T↓1/2 = 130 K, T↑1/2 = 131 K). However, raising the temperature to 170-200 K leads to formation of a modulated structure HT2(HS) exhibiting the next reversible HT2(HS) ⇄ HT2(LS) SCO (T↓1/2 = 121 K, T↑1/2 = 123 K). Finally, heating above 200 K involves the HT2(HS) → LT(HS) PT and results in a LT(HS) structure exhibiting incomplete LT(HS) ⇄ LT(HS/LS) spin crossover.

13.
Beilstein J Org Chem ; 16: 756-762, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32362949

RESUMO

Herein, we present an efficient synthesis of dipeptide analogues of α-fluorinated ß-aminophosphonates. Each step of the synthesis was optimized to provide excellent yields. Moreover, the absolute configuration of the obtained compounds was determined by X-ray analysis, which proved the stereochemistry that was proposed based on NMR studies.

14.
Front Chem ; 7: 526, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448256

RESUMO

Mono- and disubstituted 4-CF3 ß-lactams at the C-3 position have been obtained stereoselectively under basic conditions. A wide range of function such as alcohols, alkyls, aryls, esters, and double and triple bonds have been introduced.

15.
RSC Adv ; 8(22): 11957-11974, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35539392

RESUMO

Direct conversion of the α-hydroxyl group by para-toluenesulfonamide to yield α-(N-tosyl)aminophosphonates is reported. α-Aminophosphonates 23a,b-37a,b were obtained from the corresponding α-hydroxyphosphonates 6a,b-21a,b in the presence of K2CO3, via the retro-Abramov reaction of the appropriate aldehydes, 1-5. The subsequent formation of imines with simultaneous addition of diethyl phosphite provided access to the α-sulfonamide phosphonates 23a,b-37a,b with better diastereoselectivity than in the case of the Pudovik reaction. The mechanism for this transformation is proposed herein. When Cbz N-protected aziridine 9a,b and phenylalanine analogue 12a,b were exploited, intramolecular substitution was observed, leading to the corresponding epoxide 38 as the sole product, or oxazolidin-2-one 39 as a minor product. Analogous substitution was not observed in the case of proline 18a,b and serine 21a,b derivatives.

16.
J Neurosci ; 37(13): 3447-3464, 2017 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28209736

RESUMO

Mutations in the Pejvakin (PJVK) gene are thought to cause auditory neuropathy and hearing loss of cochlear origin by affecting noise-induced peroxisome proliferation in auditory hair cells and neurons. Here we demonstrate that loss of pejvakin in hair cells, but not in neurons, causes profound hearing loss and outer hair cell degeneration in mice. Pejvakin binds to and colocalizes with the rootlet component TRIOBP at the base of stereocilia in injectoporated hair cells, a pattern that is disrupted by deafness-associated PJVK mutations. Hair cells of pejvakin-deficient mice develop normal rootlets, but hair bundle morphology and mechanotransduction are affected before the onset of hearing. Some mechanotransducing shorter row stereocilia are missing, whereas the remaining ones exhibit overextended tips and a greater variability in height and width. Unlike previous studies of Pjvk alleles with neuronal dysfunction, our findings reveal a cell-autonomous role of pejvakin in maintaining stereocilia architecture that is critical for hair cell function.SIGNIFICANCE STATEMENT Two missense mutations in the Pejvakin (PJVK or DFNB59) gene were first identified in patients with audiological hallmarks of auditory neuropathy spectrum disorder, whereas all other PJVK alleles cause hearing loss of cochlear origin. These findings suggest that complex pathogenetic mechanisms underlie human deafness DFNB59. In contrast to recent studies, we demonstrate that pejvakin in auditory neurons is not essential for normal hearing in mice. Moreover, pejvakin localizes to stereociliary rootlets in hair cells and is required for stereocilia maintenance and mechanosensory function of the hair bundle. Delineating the site of the lesion and the mechanisms underlying DFNB59 will allow clinicians to predict the efficacy of different therapeutic approaches, such as determining compatibility for cochlear implants.


Assuntos
Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/patologia , Perda Auditiva Neurossensorial/metabolismo , Perda Auditiva Neurossensorial/patologia , Mecanotransdução Celular , Proteínas/metabolismo , Animais , Linhagem Celular , Audição , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Mutação/genética , Proteínas/genética , Estereocílios/metabolismo , Estereocílios/patologia
17.
Neuroscience ; 344: 380-393, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28089576

RESUMO

Mutations in the Pejvakin (Pjvk) gene cause autosomal recessive hearing loss DFNB59 with audiological features of auditory neuropathy spectrum disorder (ANSD) or cochlear dysfunction. The precise mechanisms underlying the variable clinical phenotypes of DFNB59 remain unclear. Here, we demonstrate that mice with conditional ablation of the Pjvk gene in all sensory hair cells or only in outer hair cells (OHCs) show similar auditory phenotypes with early-onset profound hearing loss. By contrast, loss of Pjvk in adult OHCs causes a slowly progressive hearing loss associated with OHC degeneration and delayed loss of inner hair cells (IHCs), indicating a primary role for pejvakin in regulating OHC function and survival. Consistent with this model, synaptic transmission at the IHC ribbon synapse is largely unaffected in sirtaki mice that carry a C-terminal deletion mutation in Pjvk. Using the C-terminal domain of pejvakin as bait, we identified in a cochlear cDNA library ROCK2, an effector for the small GTPase Rho, and the scaffold protein IQGAP1, involved in modulating actin dynamics. Both ROCK2 and IQGAP1 associate via their coiled-coil domains with pejvakin. We conclude that pejvakin is required to sustain OHC activity and survival in a cell-autonomous manner likely involving regulation of Rho signaling.


Assuntos
Células Ciliadas Auditivas Externas/metabolismo , Perda Auditiva/metabolismo , Proteínas/metabolismo , Animais , Sobrevivência Celular/fisiologia , Progressão da Doença , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas Internas/patologia , Células Ciliadas Auditivas Externas/patologia , Células HeLa , Perda Auditiva/patologia , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Proteínas/genética , RNA Mensageiro/metabolismo , Deleção de Sequência , Sinapses/metabolismo , Técnicas de Cultura de Tecidos , Proteínas Ativadoras de ras GTPase/metabolismo , Quinases Associadas a rho/metabolismo
18.
J Neurosci ; 35(47): 15582-98, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26609154

RESUMO

Disordered protein ubiquitination has been linked to neurodegenerative disease, yet its role in inner ear homeostasis and hearing loss is essentially unknown. Here we show that progressive hearing loss in the ethylnitrosourea-generated mambo mouse line is caused by a mutation in Usp53, a member of the deubiquitinating enzyme family. USP53 contains a catalytically inactive ubiquitin-specific protease domain and is expressed in cochlear hair cells and a subset of supporting cells. Although hair cell differentiation is unaffected in mambo mice, outer hair cells degenerate rapidly after the first postnatal week. USP53 colocalizes and interacts with the tight junction scaffolding proteins TJP1 and TJP2 in polarized epithelial cells, suggesting that USP53 is part of the tight junction complex. The barrier properties of tight junctions of the stria vascularis appeared intact in a biotin tracer assay, but the endocochlear potential is reduced in adult mambo mice. Hair cell degeneration in mambo mice precedes endocochlear potential decline and is rescued in cochlear organotypic cultures in low potassium milieu, indicating that hair cell loss is triggered by extracellular factors. Remarkably, heterozygous mambo mice show increased susceptibility to noise injury at high frequencies. We conclude that USP53 is a novel tight junction-associated protein that is essential for the survival of auditory hair cells and normal hearing in mice, possibly by modulating the barrier properties and mechanical stability of tight junctions. SIGNIFICANCE STATEMENT: Hereditary hearing loss is extremely prevalent in the human population, but many genes linked to hearing loss remain to be discovered. Forward genetics screens in mice have facilitated the identification of genes involved in sensory perception and provided valuable animal models for hearing loss in humans. This involves introducing random mutations in mice, screening the mice for hearing defects, and mapping the causative mutation. Here, we have identified a mutation in the Usp53 gene that causes progressive hearing loss in the mambo mouse line. We demonstrate that USP53 is a catalytically inactive deubiquitinating enzyme and a novel component of tight junctions that is necessary for sensory hair cell survival and inner ear homeostasis.


Assuntos
Progressão da Doença , Perda Auditiva/genética , Perda Auditiva/patologia , Heterozigoto , Mutação/genética , Proteases Específicas de Ubiquitina/genética , Sequência de Aminoácidos , Animais , Cóclea/patologia , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular
19.
Heart Lung Circ ; 24(8): 817-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25797323

RESUMO

BACKGROUND: Although both chronic obstructive pulmonary disease (COPD) and cardiovascular diseases (CVD) are characterised by chronic, systemic inflammation, their reciprocal interactions are poorly understood. The purpose of this study was to determine the concentrations of both inflammatory and oxidative stress biomarkers in the serum and exhaled breath condensate (EBC) of COPD patients, either with coexisting CVD or without cardio-vascular comorbidities. METHODS: Twenty-four COPD patients with CVD were allocated to group A, 20 COPD patients without CVD were assigned to group B and 16 healthy patients were included as a control. A medical history and physical examination were performed, and the following were measured: serum CRP concentration, glucose level, uraemic acid level and lipid profile. In addition 8-isoprostane, LTB4 and IL-8 concentrations were measured both in serum and EBC. Spirometry, six-minute walk test and echocardiography were performed in all subjects. RESULTS: EBC concentrations of 8-isoprostane and LTB4, and serum levels of CRP, 8-soprostane, LTB4, IL-8 were significantly higher in COPD patients than in healthy controls. COPD patients with CVD were not found to have higher concentrations of the assessed markers than those without CVD, neither in the serum nor EBC. CRP, 8-isoprostane and LTB4 levels in serum, and IL-8 concentration in EBC correlated negatively with the value of forced expiratory volume in one second. CONCLUSIONS: Although systemic inflammation coexists with COPD, it is not elevated in COPD patients with CVD. Since this phenomenon may result from treatment with statins, future studies should state whether COPD patients could benefit from the additional statin therapy.


Assuntos
Doenças Cardiovasculares/metabolismo , Dinoprosta/análogos & derivados , Mediadores da Inflamação/metabolismo , Interleucina-8/metabolismo , Leucotrieno B4/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Idoso , Biomarcadores/metabolismo , Testes Respiratórios , Doenças Cardiovasculares/epidemiologia , Comorbidade , Dinoprosta/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia
20.
Pol Arch Med Wewn ; 124(6): 290-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24824617

RESUMO

INTRODUCTION:  Inflammation and oxidative stress play an essential role in the pathogenesis of chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD). OBJECTIVES:  The aim of the study was to evaluate the echocardiographic parameters of the left and right ventricular functions in patients with COPD with or without CVD and in healthy controls, and to establish their relationships with biomarkers of inflammation and oxidative stress. PATIENTS AND METHODS:  The study included 24 patients with COPD and CVD, 20 patients with COPD, and 16 healthy controls. Physical examination, spirometry, and echocardiography were performed in all participants, and blood samples were collected. The levels of 8­isoprostane, leukotriene B4, and interleukin 8 were determined in the blood and exhaled breath condensate (EBC). RESULTS:  In patients with COPD, the left ventricular ejection fraction was lower than in healthy controls (58.84% ±9.57% vs. 65.50% ±3.35%, P <0.01); moreover, it was lower in patients with COPD and CVD than in those without comorbidities (54.29% ±10.58% vs. 64.30% ±3.74%, P <0.01). The systolic and diastolic functions of the right ventricle were lower in patients with COPD than in the control group, while systolic pulmonary arterial pressure was significantly higher in patients with COPD than in the control group (37.04 ±7.6 mmHg vs. 28.12 ±4.44 mmHg, P = 0.01). Some echocardiographic parameters of the left and right ventricular functions correlated with the concentrations of inflammatory markers both in serum and EBC. CONCLUSIONS:  The echocardiographic parameters of cardiac function correlate with the markers of inflammation in patients with COPD, which emphasizes the inflammatory background of CVD.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/etiologia , Ecocardiografia , Inflamação/complicações , Doença Pulmonar Obstrutiva Crônica/etiologia , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia , Idoso , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/fisiopatologia , Diástole , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Inflamação/sangue , Interleucina-8/sangue , Leucotrieno B4/sangue , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sístole
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