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1.
Sci Rep ; 14(1): 2231, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278834

RESUMO

Phenotypic degeneration in Cordyceps militaris poses a significant concern for producers, yet the mechanisms underlying this phenomenon remain elusive. To address this concern, we isolated two strains that differ in their abilities to form fruiting bodies. Our observations revealed that the degenerated strain lost the capacity to develop fruiting bodies, exhibited limited radial expansion, increased spore density, and elevated intracellular glycerol levels. Transcriptome reanalysis uncovered dysregulation of genes involved in the MAPK signaling pathway in the degenerate strain. Our RT-qPCR results demonstrated reduced expression of sexual development genes, along with upregulation of genes involved in asexual sporulation, glycerol synthesis, and MAPK regulation, when compared to the wild-type strain. Additionally, we discovered that osmotic stress reduced radial growth but increased conidia sporulation and glycerol accumulation in all strains. Furthermore, hyperosmotic stress inhibited fruiting body formation in all neutralized strains. These findings indicate dysregulation of the MAPK signaling pathway, the possibility of the activation of the high-osmolarity glycerol and spore formation modules, as well as the downregulation of the pheromone response and filamentous growth cascades in the degenerate strain. Overall, our study sheds light on the mechanisms underlying Cordyceps militaris degeneration and identifies potential targets for improving cultivation practices.


Assuntos
Cordyceps , Transcriptoma , Pressão Osmótica , Glicerol/metabolismo , Esporos Fúngicos/genética , Carpóforos/metabolismo
2.
Heliyon ; 8(12): e12222, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36544845

RESUMO

Aim: This article aims to determine the contributing indications for primary cesarean sections among full-term pregnant women with non-previous uterine scars and suggests several potential solutions to reduce the cesarean section rate. Methods: This is a descriptive study with data being retrospectively collected from electronic medical records (EMRs) at Hanoi Obstetrics & Gynecology Hospital, Vietnam, in 2020. We studied 23,631 women at ≥37 weeks of gestation with non-previous uterine scars. Main ICD-10 categories of diagnosis on the EMRs were used to classify the indications. The proportions of indications for primary cesarean sections were calculated, thereby offering potential solutions to reduce the cesarean section rate. Results: The proportion of cesarean sections among full-term pregnancies with non-previous uterine scars was 40.7%. The most common indications for primary cesarean sections were non-reassuring fetal heart rate tracing (40%), labor arrest (31%), and maternal request (11%). Among the low-risk pregnant women, the cesarean section rate was 35.9%, of which the percentages of labor arrest and non-reassuring fetal heart rate tracings and maternal request were 13.6%, 17.7%, and 4.6%, respectively. Conclusions: The proportion of primary cesarean sections among full-term pregnancies with non-previous uterine scars is high; non-reassuring fetal heart rate tracings, labor arrest, and maternal request were three main indications. It is necessary to build the strategies of health organizations regarding the management of clinical practices and the programs improving the knowledge, attitudes, practices of pregnant women and obstetricians regarding cesarean sections.

3.
Vaccines (Basel) ; 10(11)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36366283

RESUMO

The current study used data surveyed with 5357 parents/guardians (parents would be used to represent both 'parents' and 'guardians' hereafter) between February and March 2022 in Vietnam to examine their willingness to vaccinate their children with current COVID-19 vaccines. It applied the multinomial logistic regression model to examine the association between the willingness of parents and selected influential factors. In addition, the reasons that made parent hesitant or unwilling to vaccinate their children were investigated. Moreover, it identified parents' preferences for vaccine origins. Approximately, 75.4% of the parents were willing, 21.3% were hesitant and 3.3% were unwilling to vaccinate their children. The most common reasons that made the parents hesitant or unwilling to vaccinate their children were their concerns about the vaccine safety, efficacy and immunity. The most and the second most preferred vaccines were those developed/originated in the US and EU, respectively. Parents who were more likely to vaccinate their children included those whose children were insured, who regularly vaccinated their children, who belonged to the vaccine priority groups, who possessed sufficient knowledge about the ways to prevent the virus or about the herd immunity, and who perceived that their children might be infected with the virus and whose children were afraid of needles. Parents who were less likely to vaccinate their children included those who were the family main income source, who had savings, and who had tertiary education or higher.

4.
J Gynecol Obstet Hum Reprod ; 51(3): 102326, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35091125

RESUMO

BACKGROUND: Cesarean scar myometrial defect as known as niche is associated with postmenstrual spotting, suprapubic pain and secondary infertility. Hysteroscopic isthmoplasty has been proposed in the treatment of niche. This study aims to determine the safety and effectiveness of hysteroscopic isthmoplasty in postmenstrual spotting treatment and improvement of spontaneous conceiving. MATERIALS AND METHOD: A prospective study was performed at Hanoi Obstetrics and Gynecology Hospital, Vietnam. We studied women who developed postmenstrual spotting related to niches and had desired to conceive for more than six months. Women with residual myometrium less than 2.5 mm were excluded. Twenty-three eligible women underwent hysteroscopic isthmoplasty with four main steps, including identification of relevant anatomy, resection of the cephalad edge of fibrosis, resection of the caudal edge of fibrosis, and ablation of the niche base. Participants were followed up at 1, 3, and 6 months postoperatively. RESULTS: The mean surgical duration was 17 min, and no complications took place. The number of women with improved postmenstrual spotting symptoms after 1, 3, and 6 months were 39.1% (9/23), 61.9% (13/21) and 68.8% (11/16), respectively. Suprapubic pain resolved in 94% (15/16) of the women in the first month. The rate of spontaneous pregnancies within 6 months of isthmoplasty was 30.4% (7/23). There were no differences in depth niche and residual myometrium thickness on ultrasound in the period before and after hysteroscopy. CONCLUSION: Our study supports that hysteroscopic isthmoplasty is a safe and effective procedure for women with a niche and postmenstrual spotting and wish to conceive.


Assuntos
Metrorragia , Doenças Uterinas , Cesárea/efeitos adversos , Feminino , Humanos , Histeroscopia/métodos , Metrorragia/etiologia , Gravidez , Estudos Prospectivos , Doenças Uterinas/cirurgia
5.
Sci Rep ; 9(1): 16439, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712739

RESUMO

In vertebrates, the steroidogenesis enzyme 5α-reductase converts testosterone to the more potent androgen 5α-dihydrotestosterone. Homologues of 5α-reductase genes have been identified in molluscs. However, recent findings suggest that vertebrate-type steroid androgens are not utilised in molluscan reproductive development. Genomic searches have revealed that molluscs do not possess many of the steroidogenic enzymes required to make testosterone, nor a nuclear androgen receptor. Consequently, the role of 5α-reductase in molluscs presents a mystery. Here, developmental exposures of Biomphalaria glabrata to selective pharmaceutical 5α-reductase inhibitors elicited a strong, highly reproducible phenotypic response characterised by the development of elongated "banana-shaped" shell morphology. In comparison to untreated snails, the shells are open-coiled and the whorls are unattached. Dutasteride (5α-reductase inhibitor) is approximately 10-times more potent at provoking the banana-shaped shell phenotype than finasteride, paralleling the pharmaceuticals' efficacy in humans. Other enzyme inhibitors with different modes of action were tested to investigate the specificity of the phenotype. However, only the pharmaceutical 5α-reductase inhibitors provoked the response. Dutasteride elicited the same phenotype in a second gastropod, Physella acuta. In the absence of evidence for de novo androgen steroidogenesis in molluscs, these findings suggest that novel substrates for 5α-reductase exist in gastropods, lending support to the contention that molluscan endocrinology differs from the well-characterised vertebrate endocrine system.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Exoesqueleto/anatomia & histologia , Colestenona 5 alfa-Redutase/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Gastrópodes/anatomia & histologia , Gastrópodes/efeitos dos fármacos , Exoesqueleto/embriologia , Animais , Água Doce , Gastrópodes/embriologia , Gastrópodes/enzimologia , Humanos
6.
J Biol Methods ; 4(3): e78, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31453232

RESUMO

Ventricular tachyarrythmia occurring in ischemic heart disease, dilated/hypertrophic cardiomyopathies or rare monogenic mutations of cardiac ion channels or associated proteins belong to the most frequent causes of sudden cardiac death (SCD). In further decades, next generation sequencing and bioinformatic analysis will become the gold standard of SCD risk stratification. At the moment, Sanger-sequencing is still obligatory in genetic diagnosis. A multiplex polymerase chain reaction (PCR) assay detecting eight SCD mutations in one reaction-tube was developed. To test the general validity of the assay, it was used with 12 patients, who had one or two of the eight mutations (LMNA, p.V256V; SCN5A, p.R1583C; RYR2, p.G1885E; MYH7, V606M; DSG2, p.T335A; KCNJ8, p.S422L; MYBPC, p.E441K; TNNT2, A38V). Thereafter, we tested the multiplex assay in a real diagnostic environment within a high risk family of several past SCD cases. This method allows efficient discrimination of multiple mutations by allele-specific PCR with standard PCR conditions. It relies on obtaining a PCR product specific to the mutation or wildtype-using primers that have the 3'end base complementary to the DNA template site, i.e. a specific primer only permits amplification to take place when its 3'terminal nucleotide matches with its target sequence. The PCR products are further analyzed by length, with Tape Station®(Agilent Technologies, Germany), a high-fidelity capillary chromatography test. The novel multiplex PCR assay strategy could be a good additional test used for SCD risk stratification. Advantages of the test are high velocity and ease of implementation, low price and flexibility of application within cardiomyopathy families for screening purposes.

7.
EPMA J ; 5(1): 15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25243024

RESUMO

Atrial fibrillation (AF) is one of the major morbidity and health economic factors in Europe and often associated with several co-morbidities. This paper (1) underlines the importance of highly professional AF management utilising a multi-disciplinary expertise, especially considering the role of AF regarding the stroke risk and prevention, (2) demonstrates the consolidated position of CVD professionals and (3) emphasises those research aspects that could deepen the understanding of the emergence and the treatment of AF and therefore helps to provide a personalised preventive and more effective management of AF. Specialised calls are considered for that within the new European Programme 'Horizon 2020'.

8.
Eukaryot Cell ; 13(3): 392-400, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24413660

RESUMO

To improve the economic viability of microalgal biodiesel, it will be essential to optimize the productivity of fuel molecules such as triacylglyceride (TAG) within the microalgal cell. To understand some of the triggers required for the metabolic switch to TAG production, we studied the effect of the carbon supply (acetate or CO2) in Chlamydomonas reinhardtii (wild type and the starchless sta6 mutant) grown under low N availability. As expected, initial rates of TAG production were much higher when acetate was present than under strictly photosynthetic conditions, particularly for the sta6 mutant, which cannot allocate resources to starch. However, in both strains, TAG production plateaued after a few days in mixotrophic cultures, whereas under autotrophic conditions, TAG levels continued to rise. Moreover, the reduced growth of the sta6 mutant meant that the greatest productivity (measured as mg TAG liter⁻¹ day⁻¹) was found in the wild type growing autotrophically. Wild-type cells responded to low N by autophagy, as shown by degradation of polar (membrane) lipids and loss of photosynthetic pigments, and this was less in cells supplied with acetate. In contrast, little or no autophagy was observed in sta6 mutant cells, regardless of the carbon supply. Instead, very high levels of free fatty acids were observed in the sta6 mutant, suggesting considerable alteration in metabolism. These measurements show the importance of carbon supply and strain selection for lipid productivity. Our findings will be of use for industrial cultivation, where it will be preferable to use fast-growing wild-type strains supplied with gaseous CO2 under autotrophic conditions rather than require an exogenous supply of organic carbon.


Assuntos
Autofagia , Dióxido de Carbono/metabolismo , Chlamydomonas reinhardtii/metabolismo , Amido/metabolismo , Triglicerídeos/biossíntese , Chlamydomonas reinhardtii/genética , Glucose-1-Fosfato Adenililtransferase/genética , Glucose-1-Fosfato Adenililtransferase/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triglicerídeos/metabolismo
9.
Mutat Res ; 760: 48-56, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24361396

RESUMO

The genotoxicity and mutagenicity of formaldehyde (FA) has been well-characterized during the last years. Besides its known direct DNA-damaging and mutagenic activity in sufficiently exposed cells, FA at low concentrations might also enhance the mutagenic and carcinogenic effects of other environmental mutagens by interfering with the repair of DNA lesions induced by these mutagens. To further assess potential co-mutagenic effects of FA, we exposed A549 human lung cells to FA in combination with various mutagens and measured the induction and removal of DNA damage by the comet assay and the production of chromosomal mutations by the cytokinesis-block micronucleus assay (CBMN assay). The mutagens tested were ionizing radiation (IR), (±)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), N-nitroso-N-methylurea (methyl nitrosourea; MNU) and methyl methanesulfonate (MMS). FA (10-75µM) did not enhance the genotoxic and mutagenic activity of these mutagens under the test conditions applied. FA alone and in combination with MNU or MMS did not affect the expression (mRNA level) of the gene of the O(6)-methylguanine-DNA methyltransferase (MGMT) in A549 cells. The results of these experiments do not support the assumption that low FA concentrations might interfere with the repair of DNA damage induced by other mutagens.


Assuntos
Aberrações Cromossômicas/efeitos dos fármacos , Desinfetantes/efeitos adversos , Sinergismo Farmacológico , Formaldeído/efeitos adversos , Neoplasias Pulmonares/patologia , Mutagênicos/efeitos adversos , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/efeitos adversos , Alquilantes/efeitos adversos , Ensaio Cometa , Combinação de Medicamentos , Raios gama/efeitos adversos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Metanossulfonato de Metila/efeitos adversos , Metilnitrosoureia/efeitos adversos , Testes para Micronúcleos , O(6)-Metilguanina-DNA Metiltransferase/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
10.
BMC Syst Biol ; 6: 151, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23216813

RESUMO

BACKGROUND: Temperature strongly affects microbial growth, and many microorganisms have to deal with temperature fluctuations in their natural environment. To understand regulation strategies that underlie microbial temperature responses and adaptation, we studied glycolytic pathway kinetics in Saccharomyces cerevisiae during temperature changes. RESULTS: Saccharomyces cerevisiae was grown under different temperature regimes and glucose availability conditions. These included glucose-excess batch cultures at different temperatures and glucose-limited chemostat cultures, subjected to fast linear temperature shifts and circadian sinoidal temperature cycles. An observed temperature-independent relation between intracellular levels of glycolytic metabolites and residual glucose concentration for all experimental conditions revealed that it is the substrate availability rather than temperature that determines intracellular metabolite profiles. This observation corresponded with predictions generated in silico with a kinetic model of yeast glycolysis, when the catalytic capacities of all glycolytic enzymes were set to share the same normalized temperature dependency. CONCLUSIONS: From an evolutionary perspective, such similar temperature dependencies allow cells to adapt more rapidly to temperature changes, because they result in minimal perturbations of intracellular metabolite levels, thus circumventing the need for extensive modification of enzyme levels.


Assuntos
Adaptação Fisiológica , Biologia Computacional , Evolução Molecular , Glicólise , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/fisiologia , Temperatura , Biocatálise , Espaço Intracelular/metabolismo , Cinética , Modelos Biológicos , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo
11.
AMB Express ; 1(1): 26, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21961566

RESUMO

Six protease fractions, namely FI, FII, FIII-1, FIII-2, FIII-3 and FIV, were isolated from Perionyx excavatus earthworm biomass by acetone precipitation, followed by serial chromatography using anion exchange, hydrophobic interaction and size exclusion chromatography. All fractions exhibited strong hydrolytic activity towards casein. The activity of six fractions towards fibrin, determined by fibrin plate assay, ranged from 44 to 831 plasmin unit.mg-1 and ranked as FIII-3 > FIII-2 > FI > FIII-1 > FIV > FII. Casein degradation was optimal at pH 7 and 11, and at 45-60°C. All fractions were considerably stable at high temperature and wide pH range. They were completely inhibited by phenylmethylsulfonyl fluoride (PMSF). The molecular weights (MW) and isoelectric points (pI) determined by 2D-electrophoresis were 27.5-34.5 kDa, and 4.3-5.2, respectively. Tandem mass spectrometry (MS) analysis was used to deduce the amino acid sequences of some peptides from FIII-1 and FIII-2. The sequences shared 16.9% and 13.2% similarity, respectively, with the fibrinolytic enzymes from two related earthworm species, Lumbricus rubellus and Eisenia fetida. The P. excavatus proteases were classified as serine proteases. They could perform rapid hydrolysis on both coagulated fibrous fibrin and soluble fibrinogen monomers without the presence of activators such as tPA or urokinase.

12.
Appl Environ Microbiol ; 75(8): 2320-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19251894

RESUMO

Industrial production of lactic acid with the current pyruvate decarboxylase-negative Saccharomyces cerevisiae strains requires aeration to allow for respiratory generation of ATP to facilitate growth and, even under nongrowing conditions, cellular maintenance. In the current study, we observed an inhibition of aerobic growth in the presence of lactic acid. Unexpectedly, the cyb2Delta reference strain, used to avoid aerobic consumption of lactic acid, had a specific growth rate of 0.25 h(-1) in anaerobic batch cultures containing lactic acid but only 0.16 h(-1) in identical aerobic cultures. Measurements of aerobic cultures of S. cerevisiae showed that the addition of lactic acid to the growth medium resulted in elevated levels of reactive oxygen species (ROS). To reduce the accumulation of lactic acid-induced ROS, cytosolic catalase (CTT1) was overexpressed by replacing the native promoter with the strong constitutive TPI1 promoter. Increased activity of catalase was confirmed and later correlated with decreased levels of ROS and increased specific growth rates in the presence of high lactic acid concentrations. The increased fitness of this genetically modified strain demonstrates the successful attenuation of additional stress that is derived from aerobic metabolism and may provide the basis for enhanced (micro)aerobic production of organic acids in S. cerevisiae.


Assuntos
Catalase/biossíntese , Ácido Láctico/metabolismo , Estresse Oxidativo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/fisiologia , Aerobiose , Catalase/genética , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/toxicidade , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/crescimento & desenvolvimento
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