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1.
Am J Hum Genet ; 108(2): 337-345, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33434492

RESUMO

Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the Müllerian ducts (MD)/Wölffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Anormalidades Congênitas/genética , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/crescimento & desenvolvimento , Mutação , Ductos Mesonéfricos/crescimento & desenvolvimento , Adulto , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 7/genética , Códon sem Sentido , Feminino , Estudos de Associação Genética , Pleiotropia Genética , Proteínas Homeobox A10/genética , Proteínas de Homeodomínio/genética , Humanos , Fator de Transcrição PAX8/genética , Herança Paterna , Penetrância , Proteínas com Domínio T/genética , Fatores de Transcrição/genética , Proteínas Wnt/genética , Ductos Mesonéfricos/anormalidades
2.
BMC Genomics ; 24(1): 705, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993794

RESUMO

BACKGROUND: Basic leucine zipper (bZIP) protein is a plant-specific transcription factor involved in various biological processes, including light signaling, seed maturation, flower development, cell elongation, seed accumulation protein, and abiotic and biological stress responses. However, little is known about the pea bZIP family. RESULTS: In this study, we identified 87 bZIP genes in pea, named PsbZIP1 ~ PsbZIP87, via homology analysis using Arabidopsis. The genes were divided into 12 subfamilies and distributed unevenly in 7 pea chromosomes. PsbZIPs in the same subfamily contained similar intron/exon organization and motif composition. 1 tandem repeat event and 12 segmental duplication events regulated the expansion of the PsbZIP gene family. To better understand the evolution of the PsbZIP gene family, we conducted collinearity analysis using Arabidopsis thaliana, Oryza sativa Japonica, Fagopyrum tataricum, Solanum lycopersicum, Vitis vinifera, and Brachypodium distachyon as the related species of pea. In addition, interactions between PsbZIP proteins and promoters containing hormone- and stress-responsive cis-acting elements suggest that the regulation of PsbZIP expression was complex. We also evaluated the expression patterns of bZIP genes in different tissues and at different fruit development stages, all while subjecting them to five hormonal treatments. CONCLUSION: These results provide a deeper understanding of PsbZIP gene family evolution and resources for the molecular breeding of pea. The findings suggested that PsbZIP genes, specifically PSbZIP49, play key roles in the development of peas and their response to various hormones.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Fabaceae , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Pisum sativum/genética , Família Multigênica , Perfilação da Expressão Gênica , Fabaceae/genética , Estresse Fisiológico/genética , Hormônios , Filogenia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Phys Chem Chem Phys ; 25(19): 13766-13771, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37159225

RESUMO

In-depth understanding of the acceptor states and origins of p-type conductivity is essential and critical to overcome the great challenge for the p-type doping of ultrawide-bandgap oxide semiconductors. In this study we find that stable NO-VGa complexes can be formed with ε(0/-) transition levels significantly smaller than those of the isolated NO and VGa defects using N2 as the dopant source. Due to the defect-induced crystal-field splitting of the p orbitals of Ga, O and N atoms, and the Coulomb binding between NO(II) and VGa(I), an a' doublet state at 1.43 eV and an a'' singlet state at 0.22 eV above the valence band maximum (VBM) are formed for the ß-Ga2O3:NO(II)-VGa(I) complexes with an activated hole concentration of 8.5 × 1017 cm-3 at the VBM, indicating the formation of a shallow acceptor level and the feasibility to obtain p-type conductivity in ß-Ga2O3 even when using N2 as the dopant source. Considering the transition from NO(II)-V0Ga(I) + e to NO(II)-V-Ga(I), an emission peak at 385 nm with a Franck-Condon shift of 1.08 eV is predicted. These findings are of general scientific significance as well as technological application significance for p-type doping of ultrawide-bandgap oxide semiconductors.

4.
Biochem Biophys Res Commun ; 591: 88-94, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34999259

RESUMO

Candida albicans is an important opportunistic fungus in the clinic. In recent years, with the widespread use of antibiotics, drug-resistant strains have been isolated in the clinic, so finding new drug targets has become an urgent problem to be solved. The vacuole and mitochondria patch (vCLAMP) and the ER-mitochondria encounter structure (ERMES) are new types of inner membrane junction systems in Saccharomyces cerevisiae. However, the functions in maintaining cell survival of the two structures have not yet been elucidated in C. albicans. In this study, VAM6 and MDM34 knockout mutants (vam6Δ/Δmet-MDM34) were constructed using an induction system regulated by the MET3 promoter. PI-positive assays showed that deletion of vCLAMP and ERMES led to abnormal growth of C. albicans. Furthermore, the vam6Δ/Δmet-MDM34 mutant exhibited obvious mitochondrial fragmentation, mtDNA damage, reduced ATP levels, and abnormal mitochondrial membrane potential, indicating its important role in maintaining the structures and functions of mitochondria. Moreover, deletion of vCLAMP and ERMES inhibited filamentous growth. Overall This study shows that vCLAMP and ERMES play important roles in maintaining the survival of C. albicans cells.


Assuntos
Candida albicans/citologia , Candida albicans/metabolismo , Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Mitocôndrias/metabolismo , Vacúolos/metabolismo , Candida albicans/crescimento & desenvolvimento , Sobrevivência Celular , Proteínas Fúngicas/metabolismo , Hifas/crescimento & desenvolvimento
5.
Fungal Genet Biol ; 160: 103674, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35227874

RESUMO

Candida albicans is a common conditional pathogenic fungus in the human body, and its infections have received widespread attention in recent years. Phosphatidylinositol and its derivatives have significant regulatory effects on many physiological processes, such as cell metabolism and growth. In this study, we identified and studied the function of the phosphatidylinositol synthase Pis1 in Candida albicans. The protein has a conserved CAPT motif and multiple transmembrane domains. GFP tagging revealed that Pis1 was located at the endoplasmic reticulum (ER). The PIS1 knockout mutant was constructed using an induction system regulated by the MET3 promoter. Growth assays showed that PIS1 is an essential gene for normal growth of Candida albicans. Overexpression of PIS1 led to high sensitivity to both ER stress and cell wall stress, and down-regulated expression of the genes involved in ER stress response and maintenance of cell wall integrity. Interestingly, PIS1 overexpression enhanced secretion of the extracellular hydrolases. Virulence assays further revealed that PIS1 overexpression increased the fungal virulence, leading to quicker death of the fungus-infected mice and more severe fungal burden in the mouse kidneys. In summary, Pis1 is involved in ER stress response, maintenance of cell wall integrity, and pathogenicity of Candida albicans.


Assuntos
CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase , Candida albicans , Proteínas Fúngicas , Animais , CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase/metabolismo , Candida albicans/metabolismo , Candida albicans/patogenicidade , Parede Celular/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Fúngicas/metabolismo , Camundongos , Virulência
6.
Genet Med ; 24(11): 2262-2273, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36112137

RESUMO

PURPOSE: Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is characterized by congenital absence of the uterus, cervix, and the upper part of the vagina in females. Whole-gene deletion and loss-of-function variants in TBX6 have been identified in association with MRKHS. We aimed to expand the spectrum of TBX6 variants in MRKHS and explore the biological effect of the variant alleles. METHODS: Rare variants in TBX6 were called from a combined multiethnic cohort of 622 probands with MRKHS who underwent exome sequencing or genome sequencing. Multiple in vitro functional experiments were performed, including messenger RNA analysis, western blotting, transcriptional activity assay, and immunofluorescence staining. RESULTS: We identified 16 rare variants in TBX6 from the combined cohort, including 1 protein-truncating variant reported in our previous study and 15 variants with unknown effects. By comparing the prevalence of TBX6 variants in the Chinese MRKHS cohort vs 1038 female controls, we observed a significant mutational burden of TBX6 in affected individuals (P = .0004, odds ratio = 5.25), suggesting a causal role of TBX6 variants in MRKHS. Of the 15 variants with uncertain effects, 7 were shown to induce a loss-of-function effect through various mechanisms. The c.423G>A (p.Leu141=) and c.839+5G>A variants impaired the normal splicing of TBX6 messenger RNA, c.422T>C (p.Leu141Pro) and c.745G>A (p.Val249Met) led to decreased protein expression, c.10C>T (p.Pro4Ser) and c.400G>A (p.Glu134Lys) resulted in perturbed transcriptional activity, and c.356G>A (p.Arg119His) caused protein mislocalization. We observed incomplete penetrance and variable expressivity in families carrying deleterious variants, which indicates a more complex genetic mechanism than classical Mendelian inheritance. CONCLUSION: Our study expands the mutational spectrum of TBX6 in MRKHS and delineates the molecular pathogenesis of TBX6 variants, supporting the association between deleterious variants in TBX6 and MRKHS.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual , Anormalidades Congênitas , Feminino , Humanos , Transtornos 46, XX do Desenvolvimento Sexual/genética , Ductos Paramesonéfricos/anormalidades , Vagina/anormalidades , RNA Mensageiro , Anormalidades Congênitas/genética , Proteínas com Domínio T/genética
7.
J Hum Genet ; 67(6): 347-352, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35022528

RESUMO

Müllerian anomaly (M.A.) is a group of congenital anatomic abnormalities caused by aberrations of the development process of the Müllerian duct. M.A. can either be isolated or be involved in Mendelian syndromes, such as Dandy-Walker syndrome, Holt-Oram syndrome and Bardet-Biedl syndrome, which are often associated with both uterus and kidney malformations. In this study, we applied a genotype-first approach to analyze the whole-exome sequencing data of 492 patients with M.A. Six potential pathogenic variants were found in five genes previously related to female urogenital deformities (PKD1, SON, SALL1, BMPR1B, ITGA8), which are partially overlapping with our patients' phenotypes. We further identified eight incidental findings in seven genes related to Mendelian syndromes without known association with reproductive anomalies (TEK, COL11A1, ANKRD11, LEMD3, DLG5, SPTB, BMP2), which represent potential phenotype expansions of these genes.


Assuntos
Anormalidades Múltiplas , Deformidades Congênitas das Extremidades Inferiores , Deformidades Congênitas das Extremidades Superiores , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Feminino , Genótipo , Humanos , Deformidades Congênitas das Extremidades Inferiores/genética , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/patologia , Deformidades Congênitas das Extremidades Superiores/genética
8.
Phys Chem Chem Phys ; 24(16): 9384-9393, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35383793

RESUMO

The emerging semiconductor boron arsenide (BAs) with high thermal conductivity has attracted much attention recently, due to its promising application to overcome the bottleneck of high-density heat generated in power electronics and optoelectronic devices. In this work, based on first-principles calculations, we find that cubic BAs possesses high intrinsic electron/hole mobilities and the ionized impurity scattering plays a more important role in carrier scattering, compared with other scattering processes. The mobilities can be significantly enhanced by 14.9% and 76.2% for electrons and holes, respectively, by strain engineering. The investigation of the optoelectronic properties of indirect semiconductor cubic BAs by considering the many-body excitonic effects reveals that the contribution from finite-momentum excitons to optical properties is larger for photon energy ranging from 2.25 eV to 3.50 eV, compared with that from zero-momentum excitons. Finally, we observe that the phonon-electron couplings to total lattice thermal conductivities are non-trivial at low temperatures. These findings provide new insight into the transport and optoelectronic properties of cubic BAs, which are beneficial for the acceleration of the application of this revolutionary thermal management material.

9.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36361644

RESUMO

Distal vaginal atresia is a rare abnormality of female reproductive tract in which the vagina is closed or absent. The distal vagina may be replaced by fibrous tissue and the condition is often not diagnosed until a girl fails to begin having periods at puberty. Although it is a congenital disorder, potential genetic causes of distal vaginal atresia are still unknown. We recruited a cohort of 39 patients with distal vaginal atresia and analyzed their phenotypic and genetic features. In addition to the complaint of distal vaginal atresia, approximately 17.9% (7/39) of the patients had other Müllerian anomalies, and 17.9% (7/39) of the patients had other structural abnormalities, including renal-tract, skeletal and cardiac anomalies. Using genome sequencing, we identified two fragment duplications on 17q12 encompassing HNF1B and LHX1, two dosage-sensitive genes with candidate pathogenic variants, in two unrelated patients. A large fragment of uniparental disomy was detected in another patient, affecting genes involved in cell morphogenesis and connective tissue development. Additionally, we reported two variants on TBX3 and AXL, leading to distal vaginal atresia in mutated mouse model, in our clinical subjects for the first time. Essential biological functions of these detected genes with pathogenic variants included regulating reproductive development and cell fate and patterning during embryogenesis. We displayed the comprehensive clinical and genetic characteristic of a cohort with distal vaginal atresia and they were highly heterogeneous both phenotypically and genetically. The duplication of 17q12 in our cohort could help to expand its phenotypic spectrum and potential contribution to the distal vaginal atresia. Our findings of pathogenic genetic variants and associated phenotypes in our cohort could provide evidence and new insight for further research attempting to reveal genetic causes of distal vaginal atresia.


Assuntos
Cardiopatias Congênitas , Maturidade Sexual , Camundongos , Animais , Feminino , Vagina , Genitália Feminina
10.
Molecules ; 27(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163951

RESUMO

Phosphorus in the form of phosphate (Pi) is an essential element for metabolic processes, including lipid metabolism. In yeast, the inositol polyphosphate kinase vip1 mediated synthesis of inositol heptakisphosphate (IP7) regulates the phosphate-responsive (PHO) signaling pathway, which plays an important role in response to Pi stress. The role of vip1 in Pi stress and lipid metabolism of Candida albicans has not yet been studied. We found that when vip1Δ/Δ was grown in glucose medium, if Pi was supplemented in the medium or mitochondrial Pi transporter was overexpressed in the strain, the lipid droplet (LD) content was reduced and membrane damage was alleviated. However, further studies showed that neither the addition of Pi nor the overexpression of the Pi transporter affected the energy balance of vip1Δ/Δ. In addition, the LD content of vip1Δ/Δ grown in Pi limitation medium PNMC was lower than that grown in SC, and the metabolic activity of vip1Δ/Δ grown in PNMC was also lower than that grown in SC medium. This suggests that the increase in Pi demand by a high energy metabolic rate is the cause of LD accumulation in vip1Δ/Δ. In addition, in the vip1Δ/Δ strains, the core transcription factor PHO4 in the PHO pathway was transported to the vacuole and degraded, which reduced the pathway activity. However, this does not mean that knocking out vip1 completely blocks the activation of the PHO pathway, because the LD content of vip1Δ/Δ grown in the medium with ß-glycerol phosphate as the Pi source was significantly reduced. In summary, the increased Pi demand and the decreased PHO pathway activity in vip1Δ/Δ ultimately lead to LD accumulation and cell membrane damage.


Assuntos
Metabolismo Energético/fisiologia , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Candida albicans/metabolismo , Membrana Celular/metabolismo , Expressão Gênica/genética , Regulação Fúngica da Expressão Gênica/genética , Fosfatos de Inositol , Gotículas Lipídicas/metabolismo , Fosfatos/metabolismo , Fosforilação , Fosfotransferases (Aceptor do Grupo Fosfato)/fisiologia , Transdução de Sinais , Fatores de Transcrição/metabolismo , Vacúolos/metabolismo
11.
J Phys Chem A ; 125(28): 6096-6108, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34240862

RESUMO

Cytidine ribonucleosides were furnished at O5' with fixed-charge 6-trimethylammoniumhexan-1-aminecarbonyl tags and studied by UV-vis photodissociation action spectroscopy in the gas phase to probe isolated nucleobase chromophores in their neutral, protonated, and hydrogen-adduct radical forms. The action spectrum of the doubly charged cytidine conjugate showed bands at 310 and 270 nm that were assigned to the N3- and O2-protonated cytosine tautomers formed by electrospray, respectively. In contrast, cytidine conjugates coordinated to dibenzo-18-crown-6-ether (DBCE) in a noncovalent complex were found to strongly favor protonation at N3, forming a single-ion tautomer. This allowed us to form cytidine N3-H radicals by electron transfer dissociation of the complex and study their action spectra. Cytidine radicals showed only very weak absorption in the visible region of the spectrum for dipole-disallowed transitions to the low (A and B) excited states. The main bands were observed at 360, 300, and 250 nm that were assigned with the help of theoretical vibronic spectra obtained by time-dependent density functional theory calculations of multiple (>300) radical vibrational configurations. Collision-induced dissociations of cytidine radicals proceeded by major cleavage of the N1-C1' glycosidic bond leading to loss of cytosine and competitive loss of N3-hydrogen atom. These dissociations were characterized by calculations of transition-state structures and energies using combined Born-Oppenheimer molecular dynamics and DFT calculations. Overall, cytidine radicals were found to be kinetically and thermodynamically more stable than previously reported analogous adenosine and guanosine radicals.

12.
Int Urogynecol J ; 32(4): 859-864, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33206221

RESUMO

INTRODUCTION AND HYPOTHESIS: Personality traits can play an important role in outcomes of different chronic disorders. We hypothesize that the pessary treatment outcomes in symptomatic pelvic organ prolapse (POP) can also be influenced by personality traits. METHODS: This prospective observational study included consecutive women with symptomatic POP seeking pessary treatment between December 2018 and January 2020. The personality profile was measured using the Eysenck Personality Questionnaire (EPQ-R) at baseline, and patient health-related quality of life (HRQoL) was measured using the Pelvic Floor Impact Questionnaire-7 (PFIQ-7) and the Pelvic Floor Distress Inventory (PFDI-20) at baseline and at 3 months. The correlation between HRQoL and personality traits was investigated by means of linear regression. RESULTS: In total, 213 patients were included, of which 163 patients (76.5%) achieved success by the 3-month follow-up. No significant differences were found in the EPQ scores between the successful and unsuccessful groups. The scores on both the PFIQ-7 and PFDI-20 correlated significantly with neuroticism and correlated inversely with extraversion at both baseline and the 3-month follow-up. The degree of improvement in PFIQ-7 and PFDI-20 scores was not associated with personality traits. CONCLUSIONS: Our data indicate that neurotic and introverted women were more bothered by POP-related symptoms, although the improvement in symptoms was not significantly associated with personality traits after 3 months of pessary treatment.


Assuntos
Prolapso de Órgão Pélvico , Pessários , Feminino , Humanos , Prolapso de Órgão Pélvico/terapia , Personalidade , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento
13.
J Minim Invasive Gynecol ; 28(6): 1203-1210, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33321256

RESUMO

STUDY OBJECTIVE: To study the long-term outcomes of laparoscopically assisted uterovaginal canalization and vaginoplasty in patients with congenital cervical and vaginal atresia and to introduce the surgery step by step. DESIGN: A prospective observational study from January 2016 to September 2019. SETTING: A tertiary teaching hospital. PATIENTS: Ten women diagnosed with congenital cervical and vaginal atresia. INTERVENTIONS: All women underwent laparoscopically assisted uterovaginal canalization and vaginoplasty. MEASUREMENTS AND MAIN RESULTS: All procedures went smoothly, with no case requiring conversion to laparotomy, and no intraoperative complications occurred. Postoperative febrile morbidity occurred in 1 patient (1/10, 10%). The median (interquartile range) follow-up time was 26.0 (21.3, 48.3) months. All patients resumed menstruation, including 9 patients (9/10, 90%) with regular monthly menstruation. Eight patients (8/10, 80%) experienced mild to moderate dysmenorrhea; the remaining 2 patients (2/10, 20%) had no dysmenorrhea. Cervical restenosis occurred in 1 patient (1/10, 10%) 12 months postoperatively, and cervical dilation was performed. So far, 8 months after the second surgery, no restenosis has been found. The mean postoperative vaginal length was 7.9 ± 1.3-cm at the time of the last follow-up. Only 1 patient attempted to conceive for 2 years, but she had not conceived yet. CONCLUSION: Laparoscopically assisted uterovaginal canalization and vaginoplasty is an easy, safe, and promising management option for correcting congenital cervical and vaginal atresia.


Assuntos
Colo do Útero , Vagina , Colo do Útero/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Menstruação , Resultado do Tratamento , Vagina/cirurgia
14.
J Acoust Soc Am ; 150(4): 2514, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34717451

RESUMO

A calculation method is proposed to investigate trapped modes in a rigid waveguide with rigid obstacles in the presence of non-potential steady mean flow in a two-dimensional coordinate system. This method facilitates the investigation of trapped modes in the presence of non-potential flow. A coupled calculation method that combines computational fluid dynamics and computational aeroacoustics is used. Galbrun's equation of aeroacoustics is used and discretized by the finite element method. The boundary condition corresponding to the unbounded domain is modeled by the perfectly matched layer technique. The proposed approach facilitates the investigation of the trapped modes generated by obstacles with different geometrical shapes. The effects of both the dimensions of different geometrical shapes (e.g., thin plate, rectangular, and elliptical) and the presence of the non-potential flow on the trapped modes are studied. It is observed that the non-potential flow alters the pressure distribution around the obstacle and the frequencies of the trapped modes. The results show good agreement with the literature. Also, experimental investigations are performed to validate the model.

15.
Mycopathologia ; 186(4): 477-486, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34057669

RESUMO

Vacuole and mitochondria patches (vCLAMPs) are involved in the stress resistance of yeast, but their exact role in autophagy remains so far unclear. This study, for the first time, investigated the role of the vCLAMP core protein Vam6 in autophagy of Candida albicans. The experiments demonstrated that the deletion of VAM6 led to a growth defect under nitrogen starvation. Also, western blotting revealed that the vam6Δ/Δ mutant attenuated degradation of Atg8 (an autophagy indicator), Lap41 (an indicator of the cytoplasm to vacuole targeting pathway), and Csp37 (a mitophagy indicator). Moreover, the activity of carboxypeptidase Y and the levels of the vacuolar phospholipase Atg15 were significantly decreased in the mutant, which confirmed the defect of autophagy caused by deletion of VAM6. Overall, these results revealed that Vam6 is essential in maintaining the autophagic process under nitrogen starvation, and this provided new insights into the correlation between vCLAMPs and autophagy.


Assuntos
Autofagia , Candida albicans , Mitocôndrias , Vacúolos , Candida albicans/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Vacúolos/metabolismo
16.
Neurourol Urodyn ; 39(8): 2238-2245, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32936968

RESUMO

AIM: To identify factors associated with unsuccessful pessary fitting in a large cohort of patients with symptomatic pelvic organ prolapse (POP). METHODS: This prospective observational study included 611 consecutive women with symptomatic POP in a tertiary-care hospital. Patients were initially fitted with a ring pessary with support. Those who failed were fitted with a Gellhorn pessary. A successful pessary fitting was defined as a patient who was fitted or refitted with a pessary and continued to use it 2 weeks later. Parametric and nonparametric tests were used for the data analysis. RESULTS: A total of 524 patients had successful pessary fittings (85.8% success rate). The success rate of the ring pessary with support was 57.9%, of the Gellhorn pessary was 69.1%. Stage IV prolapse (odds ratio [OR], 2.12), posterior compartment prolapse (OR, 1.92), genital hiatus (OR, 1.41), and vaginal introitus (OR, 1.40) were independent predictors of unsuccessful ring with support pessary fitting. Vaginal length (OR, 0.74/0.60 for ring with support/Gellhorn) and history of POP reconstructive surgery (OR, 2.50/2.58 for ring with support/Gellhorn) were independent predictors of both ring with support and Gellhorn pessary fitting. CONCLUSIONS: Stage IV prolapse, posterior compartment prolapse, large genital hiatus, and wide vaginal introitus were risk factors for unsuccessful fitting of ring pessary with support. Short vaginal length and a history of POP reconstructive surgery were risk factors for unsuccessful fitting of both pessaries.


Assuntos
Prolapso de Órgão Pélvico/terapia , Pessários , Vagina , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Appl Microbiol Biotechnol ; 104(16): 7143-7153, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32623494

RESUMO

The gut microbiota is crucial in the pathogenesis of type 2 diabetes mellitus (T2DM). However, the metabolism of T2DM patients is not well-understood. We aimed to identify the differences on composition and function of gut microbiota between T2DM patients with obesity and healthy people. In this study, 6 T2DM patients with obesity and 6 healthy volunteers were recruited, and metagenomic approach and bioinformatics analysis methods were used to understand the composition of the gut microbiota and the metabolic network. We found a decrease in the abundance of Firmicutes, Oribacterium, and Paenibacillus; this may be attributed to a possible mechanism and biological basis of T2DM; moreover, we identified three critical bacterial taxa, Bacteroides plebeius, Phascolarctobacterium sp. CAG207, and the order Acidaminococcales that can potentially be used for T2DM treatment. We also revealed the composition of the microbiota through functional annotation based on multiple databases and found that carbohydrate metabolism contributed greatly to the pathogenesis of T2DM. This study helps in elucidating the different metabolic roles of microbes in T2DM patients with obesity.


Assuntos
Bactérias/classificação , Diabetes Mellitus Tipo 2/microbiologia , Microbioma Gastrointestinal , Metagenoma , Obesidade/microbiologia , Adulto , Bactérias/metabolismo , Biologia Computacional , Diabetes Mellitus Tipo 2/fisiopatologia , Fezes/microbiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade
18.
J Pineal Res ; 67(2): e12584, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31050371

RESUMO

Brain insulin resistance, induced by neuroinflammation and oxidative stress, contributes to neurodegeneration, that is, processes that are associated with Aß accumulation and TAU hyperphosphorylation. Here, we tested the effect of chronic administration of melatonin (MLT) on brain insulin resistance and cognition deficits caused by a high-fat diet (HFD) in aged rats. Results showed that MLT supplementation attenuated peripheral insulin resistance and lowered hippocampal oxidative stress levels. Activated microglia and astrocytes and hippocampal levels of TNF-α in HFD-fed rats were reduced by MLT treatment. Melatonin also prevented HFD-induced increases in beta-amyloid (Aß) accumulation and TAU phosphorylation in the hippocampus. In addition, impairments of brain insulin signaling elicited by long-term HFD were restored by MLT treatment, as confirmed by ex vivo insulin stimulation. Importantly, MLT reversed HFD-induced cognitive decline as measured by a water maze test, normalized hippocampal LTP and restored CREB activity and BDNF levels as well as cholinergic neuronal activity in the hippocampus. Collectively, these findings indicate that MLT may exhibit substantial protective effects on cognition, via restoration of brain insulin signaling.


Assuntos
Envelhecimento , Disfunção Cognitiva , Gorduras na Dieta/efeitos adversos , Hipocampo , Resistência à Insulina , Melatonina/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Gorduras na Dieta/farmacologia , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Aprendizagem em Labirinto/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
19.
Can J Microbiol ; 65(12): 913-921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491332

RESUMO

This study reports the use of reverse transcription - loop-mediated isothermal amplification (RT-LAMP) to detect Listeria monocytogenes in meat. The assay was designed to target the iap gene of L. monocytogenes, to which four primers, recognizing six distinct iap sites, were designed. We optimized the RT-LAMP conditions and established the following optimal systems: 60 min, 63 °C, 2.0 mmol/L MgSO4, 1.0 mol/L betaine, 2.0 mmol/L dNTPs, 320 U/mL Bst DNA polymerase, 0.4 µmol/L outer primers, and 0.8 µmol/L inner primers. The RT-LAMP amplification products were identified by a visible white Mg2P2O7 precipitate or electrophoresis on a 2% agarose gel. RT-LAMP has a sensitivity of 7.3 × 101 CFU/mL, which is 2-fold higher than that of LAMP. When commercially available raw meat samples (including beef, pork, mutton, and rabbit) were analyzed simultaneously with RT-LAMP and the Chinese National Standard GB 4789.30-2016, their abilities to detect L. monocytogenes were the same. Samples containing L. monocytogenes killed by 15 psi at 121 °C for 15 min were used to confirm the specificity of RT-LAMP for live microorganisms. Thus, we used RT-LAMP to efficiently detect L. monocytogenes in meat products.


Assuntos
Microbiologia de Alimentos/métodos , Listeria monocytogenes/isolamento & purificação , Produtos da Carne/microbiologia , Técnicas de Amplificação de Ácido Nucleico , Animais , Proteínas de Bactérias/genética , Lipoproteínas/genética , Listeria monocytogenes/genética , Carne/microbiologia , Sensibilidade e Especificidade
20.
Mycopathologia ; 184(5): 573-583, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473908

RESUMO

Candida albicans is one of the most important fungal pathogens. Hyphal development is required for the virulence of this pathogen. Our previous study has revealed that Spf1, an ER P-type calcium pump, plays an important role in hyphal development. However, the detailed mechanisms by which this protein functions in this process remain to be investigated. In this study, we found that loss of Spf1 led to decreased growth biomass under the hypha-inducing condition, suggesting a role of this protein in maintaining hyphal growth rate. Actin staining further revealed that the spf1Δ/Δ mutant showed attenuated tip-localization of actin patches and the defect in transport of both the chitin synthase Chs3 and the hypha-related factor Hwp1, implying that Spf1 functions in polarized growth of the hyphae by regulating actin organization and consequent polarized transport of morphogenesis-associated factors. Moreover, deletion of SPF1 led to abnormal vacuolar morphology under the hypha-inducing condition, which may also contribute to the defect of hyphal development in the spf1Δ/Δ mutant. This study revealed the pleiotropic role of Spf1-regulated calcium homeostasis in controlling hyphal development in C. albicans.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Cálcio/metabolismo , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Transportadores de Cassetes de Ligação de ATP/deficiência , Candida albicans/genética , Deleção de Genes , Hifas/genética
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