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1.
J Biomech Eng ; 145(12)2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37578172

RESUMEN

Ossification of the posterior longitudinal ligament (OPLL) has been identified as an important cause of cervical myelopathy. However, the biomechanical mechanism between the OPLL type and the clinical characteristics of myelopathy remains unclear. The aim of this study was to evaluate the effect of different types of OPLL on the dynamic biomechanical response of the spinal cord. A three-dimensional finite element model of the fluid-structure interaction of the cervical spine with spinal cord was established and validated. The spinal cord stress and strain, cervical range of motion (ROM) in different types of OPLL models were predicted during dynamic flexion and extension activity. Different types of OPLL models showed varying degrees of increase in stress and strain under the process of flexion and extension, and there was a surge toward the end of extension. Larger spinal cord stress was observed in segmental OPLL. For continuous and mixed types of OPLL, the adjacent segments of OPLL showed a dramatic increase in ROM, while the ROM of affected segments was limited. As a dynamic factor, flexion and extension of the cervical spine play an amplifying role in OPLL-related myelopathy, while appropriate spine motion is safe and permitted. Segmental OPLL patients are more concerned about the spinal cord injury induced by large stress, and patients with continuous OPLL should be noted to progressive injuries of adjacent level.


Asunto(s)
Osificación del Ligamento Longitudinal Posterior , Enfermedades de la Médula Espinal , Humanos , Ligamentos Longitudinales/fisiología , Análisis de Elementos Finitos , Osteogénesis , Enfermedades de la Médula Espinal/etiología , Osificación del Ligamento Longitudinal Posterior/complicaciones , Vértebras Cervicales
2.
Geriatr Nurs ; 51: 54-64, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36893611

RESUMEN

OBJECTIVE: The aim of this review was to evaluate the overall diagnostic performance of e-devices for detection of health problems in older adults at home. METHODS: A systematic review was conducted following the PRISMA-DTA guidelines. RESULTS: 31 studies were included with 24 studies included in meta-analysis. The included studies were divided into four categories according to the signals detected: physical activity (PA), vital signs (VS), electrocardiography (ECG) and other. The meta-analysis showed the pooled estimates of sensitivity and specificity were 0.94 and 0.98 respectively in the 'VS' group. The pooled sensitivity and specificity were 0.97 and 0.98 respectively in the 'ECG' group. CONCLUSIONS: All kinds of e-devices perform well in diagnosing the common health problems. While ECG-based health problems detection system is more reliable than VS-based ones. For sole signal detection system has limitation in diagnosing specific health problems, more researches should focus on developing new systems combined of multiple signals.


Asunto(s)
Ejercicio Físico , Humanos , Anciano , Sensibilidad y Especificidad
3.
Lab Invest ; 102(9): 1023-1037, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35585132

RESUMEN

Irritable bowel syndrome (IBS) is characterized by visceral hypersensitivity (VH) associated with abnormal serotonin/5-hydroxytryptamine (5-HT) metabolism and neurotrophin-dependent mucosal neurite outgrowth. The underlying mechanisms of VH remain poorly understood. We investigated the role of 5-HT7 receptor in mucosal innervation and intestinal hyperalgesia. A high density of mucosal nerve fibres stained for 5-HT7 was observed in colonoscopic biopsy specimens from IBS patients compared with those from healthy controls. Staining of 5-HT3 and 5-HT4 receptors was observed mainly in colonic epithelia with comparable levels between IBS and controls. Visceromotor responses to colorectal distension were evaluated in two mouse models, one postinfectious with Giardia and subjected to water avoidance stress (GW) and the other postinflammatory with trinitrobenzene sulfonic acid-induced colitis (PT). Increased VH was associated with higher mucosal density of 5-HT7-expressing nerve fibres and elevated neurotrophin and neurotrophin receptor levels in the GW and PT mice. The increased VH was inhibited by intraperitoneal injection of SB-269970 (a selective 5-HT7 antagonist). Peroral multiple doses of CYY1005 (a novel 5-HT7 ligand) decreased VH and reduced mucosal density of 5-HT7-expressing nerve fibres in mouse colon. Human neuroblastoma SH-SY5Y cells incubated with bacteria-free mouse colonic supernatant, 5-HT, nerve growth factor, or brain-derived neurotrophic factor exhibited nerve fibre elongation, which was inhibited by 5-HT7 antagonists. Gene silencing of HTR7 also reduced the nerve fibre length. Activation of 5-HT7 upregulated NGF and BDNF gene expression, while stimulation with neurotrophins increased the levels of tryptophan hydroxylase 2 and 5-HT7 in neurons. A positive-feedback loop was observed between serotonin and neurotrophin pathways via 5-HT7 activation to aggravate fibre elongation, whereby 5-HT3 and 5-HT4 had no roles. In conclusion, 5-HT7-dependent mucosal neurite outgrowth contributed to VH. A novel 5-HT7 antagonist could be used as peroral analgesics for IBS-related pain.


Asunto(s)
Síndrome del Colon Irritable , Neuroblastoma , Animales , Humanos , Mucosa Intestinal , Ratones , Proyección Neuronal , Serotonina
4.
Bioorg Chem ; 109: 104685, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33640631

RESUMEN

The monoamine oxidase-B (MAO-B) inhibitors with neuroprotective effects are better for Parkinson's disease (PD) treatment, due to the complicated pathogenesis of PD. To develop new hMAO-B inhibitors with neuroprotection, a novel series of 3,4-dihydrocoumarins was designed as selective and reversible hMAO-B inhibitors to treat PD. Most compounds showed potent and selective inhibition for hMAO-B over hMAO-A with IC50 values ranging from nanomolar to sub-nanomolar. Among them, compound 4d was the most potent hMAO-B inhibitor (IC50 = 0.37 nM) being about 20783-fold more active than iproniazid, and exhibited the highest selectivity for hMAO-B (SI > 270,270). Kinetic studies revealed that compound 4d was a reversible and competitive inhibitor of hMAO-B. Neuroprotective studies indicated that compound 4d could protect PC12 cells from the damage induced by 6-OHDA and rotenone. Besides, compound 4d did not exhibit acute toxicity at a dose up to 2500 mg/kg (po), and could cross the BBB in parallel artificial membrane permeability assay. More importantly, compound 4d was able to significantly prevent the motor deficits in the MPTP-induced PD model. These results indicate that compound 4d is an effective and promising candidate against PD.


Asunto(s)
Cumarinas/química , Diseño de Fármacos , Intoxicación por MPTP/tratamiento farmacológico , Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/metabolismo , Animales , Indanos/farmacología , Ratones , Modelos Moleculares , Estructura Molecular , Inhibidores de la Monoaminooxidasa/química , Oxidopamina/toxicidad , Células PC12 , Conformación Proteica , Ratas , Rotenona/toxicidad , Relación Estructura-Actividad
5.
Sensors (Basel) ; 21(15)2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34372459

RESUMEN

Atrial fibrillation (AF) is the most common cardiovascular disease (CVD), and most existing algorithms are usually designed for the diagnosis (i.e., feature classification) or prediction of AF. Artificial intelligence (AI) algorithms integrate the diagnosis of AF electrocardiogram (ECG) and predict the possibility that AF will occur in the future. In this paper, we utilized the MIT-BIH AF Database (AFDB), which is composed of data from normal people and patients with AF and onset characteristics, and the AFPDB database (i.e., PAF Prediction Challenge Database), which consists of data from patients with Paroxysmal AF (PAF; the records contain the ECG preceding an episode of PAF), and subjects who do not have documented AF. We extracted the respective characteristics of the databases and used them in modeling diagnosis and prediction. In the aspect of model construction, we regarded diagnosis and prediction as two classification problems, adopted the traditional support vector machine (SVM) algorithm, and combined them. The improved quantum particle swarm optimization support vector machine (IQPSO-SVM) algorithm was used to speed the training time. During the verification process, the clinical FZU-FPH database created by Fuzhou University and Fujian Provincial Hospital was used for hybrid model testing. The data were obtained from the Holter monitor of the hospital and encrypted. We proposed an algorithm for transforming the PDF ECG waveform images of hospital examination reports into digital data. For the diagnosis model and prediction model trained using the training set of the AFDB and AFPDB databases, the sensitivity, specificity, and accuracy measures were 99.2% and 99.2%, 99.2% and 93.3%, and 91.7% and 92.5% for the test set of the AFDB and AFPDB databases, respectively. Moreover, the sensitivity, specificity, and accuracy were 94.2%, 79.7%, and 87.0%, respectively, when tested using the FZU-FPH database with 138 samples of the ECG composed of two labels. The composite classification and prediction model using a new water-fall ensemble method had a total accuracy of approximately 91% for the test set of the FZU-FPH database with 80 samples with 120 segments of ECG with three labels.


Asunto(s)
Fibrilación Atrial , Máquina de Vectores de Soporte , Algoritmos , Inteligencia Artificial , Fibrilación Atrial/diagnóstico , Electrocardiografía , Humanos
6.
J Am Chem Soc ; 142(15): 6946-6950, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32227926

RESUMEN

Chiral organic-inorganic perovskites (COIPs) have recently attracted increasing interest due to their unique inherent chirality and potential applications in next-generation optoelectronic and spintronic devices. However, COIP ferroelectrics are very sparse. In this work, for the first time, we present the nickel-nitrite ABX3 COIP ferroelectrics, [(R and S)-N-fluoromethyl-3-quinuclidinol]Ni(NO2)3 ([(R and S)-FMQ]Ni(NO2)3), where the X-site is the rarely seen NO2- bridging ligand. [(R and S)-FMQ]Ni(NO2)3 display mirror-relationship in the crystal structure and vibrational circular dichroism signal. It is emphasized that [(R and S)-FMQ]Ni(NO2)3 show splendid ferroelectricity with both an extremely high phase-transition point of 405 K and a spontaneous polarization of 12 µC/cm2. To our knowledge, [(R and S)-FMQ]Ni(NO2)3 are the first examples of nickel-nitrite based COIP ferroelectrics. This finding expands the COIP family and throws light on exploration of high-performance COIP ferroelectrics.

7.
Acta Pharmacol Sin ; 41(2): 181-191, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31142800

RESUMEN

Breast cancer resistance protein (BCRP) is one of ATP-binding cassette (ABC) transporters in brain microvessel endothelial cells that transport their substrates from brain to blood, thus limiting substrates to crossing into brain through blood-brain barrier. Our previous works show that bile duct ligation (BDL) impairs expression and function of brain BCRP in rats. Since zidovudine (AZT) is BCRP substrate, we investigated whether impaired expression and function of BCRP increased brain distribution and toxicity of AZT in BDL-D7 rats. After administration of AZT (10 mg/kg, i.v.), BDL markedly increased brain AZT concentrations, compared with sham-operated (SO) rats. The ratio of AZT brain-to-plasma area under concentration curve (AUC) in BDL rats was increased to 1.6-folds of SO rats. After treatment with AZT (100 mg/kg every day, i.v.) for 7 days, BDL significantly impaired cognitive functions compared with SO rats, evidenced by the significantly decreased percentage of alternation in Y-maze test and prolonged escaped latency in two-way passive avoidance trial. Furthermore, AZT treatment caused significant decrease in copies of mitochondrial DNA and mitochondrial membrane potential in hippocampus of BDL rats. Moreover, AZT treatment caused a significant decrease of cortex microtubule-associated protein 2 and hippocampus synaptophysin levels in BDL rats. AZT-induced CNS adverse alterations in BDL rats were not observed in SO rats treated with AZT. In conclusion, BDL decreases the function and expression of brain BCRP in rats, leading to increased brain distribution of AZT, which in turn enhances AZT CNS toxicity, leading to mitochondrial dysfunction, neuronal damage, and ultimately cognitive dysfunction.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Fármacos Anti-VIH/toxicidad , Encéfalo/efectos de los fármacos , Zidovudina/toxicidad , Animales , Fármacos Anti-VIH/farmacocinética , Área Bajo la Curva , Conductos Biliares/patología , Barrera Hematoencefálica/metabolismo , Encéfalo/patología , Línea Celular , Cognición/efectos de los fármacos , Disfunción Cognitiva/inducido químicamente , Perros , Humanos , Células de Riñón Canino Madin Darby , Masculino , Ratas , Ratas Sprague-Dawley , Distribución Tisular , Zidovudina/farmacocinética
8.
Planta Med ; 86(16): 1176-1184, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32645740

RESUMEN

Juniperus (Cupressaceae, Pinales) plants are widely distributed in the Qinghai-Tibet Plateau of China. The leaves and twigs of at least 8 Juniperus species (J. pingii, J. pingii var. wilsonii, J. squamata, J. recurva var. coxii, J. saltuaria, J. indica, J. tibetica and J. convallium var. microsperma) have been used as the Tibetan medicine Xuba. At present, it is difficult to distinguish among the original species of Xuba based only on their similar morphological characteristics. However, in our previous studies, 4 Xuba samples from different Juniperus species exhibited significant differences in both anticomplementary activity in vitro and anti-inflammatory effects on acute lung injury in vivo. To identify the effective original species of Xuba reliably, in this study, we developed a sequencing-based DNA molecular technology to distinguish 14 populations of 8 Juniperus species collected from Tibet region, using trnS-G, trnD - T, and petN-psbM genomic regions to build phylogenetic trees. In addition, their anticomplementary activities were evaluated. The results showed that combined sequence of these 3 genomic regions could identify 8 Juniperus species clearly and clustered individuals of one species but from different locations, whichever phylogenetic tree was constructed. Moreover, the anticomplementary activities of the 8 species were clustered into 2 groups. Among them, J. saltuaria and J. recurva var. coxii, which formed an independent branch apart from the other 6 species in phylogenetic trees, were the most potent (CH50: 0.029 - 0.032 mg/mL). Consequently, DNA identification of Juniperus using the combined sequence could provide beneficial guidance for further efficacy evaluation and quality control of Xuba.


Asunto(s)
Juniperus , China , Cloroplastos , Humanos , Filogenia , Tibet
9.
J Med Internet Res ; 22(5): e19540, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32353827

RESUMEN

BACKGROUND: Low infection and case-fatality rates have been thus far observed in Taiwan. One of the reasons for this major success is better use of big data analytics in efficient contact tracing and management and surveillance of those who require quarantine and isolation. OBJECTIVE: We present here a unique application of big data analytics among Taiwanese people who had contact with more than 3000 passengers that disembarked at Keelung harbor in Taiwan for a 1-day tour on January 31, 2020, 5 days before the outbreak of coronavirus disease (COVID-19) on the Diamond Princess cruise ship on February 5, 2020, after an index case was identified on January 20, 2020. METHODS: The smart contact tracing-based mobile sensor data, cross-validated by other big sensor surveillance data, were analyzed by the mobile geopositioning method and rapid analysis to identify 627,386 potential contact-persons. Information on self-monitoring and self-quarantine was provided via SMS, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tests were offered for symptomatic contacts. National Health Insurance claims big data were linked, to follow-up on the outcome related to COVID-19 among those who were hospitalized due to pneumonia and advised to undergo screening for SARS-CoV-2. RESULTS: As of February 29, a total of 67 contacts who were tested by reverse transcription-polymerase chain reaction were all negative and no confirmed COVID-19 cases were found. Less cases of respiratory syndrome and pneumonia were found after the follow-up of the contact population compared with the general population until March 10, 2020. CONCLUSIONS: Big data analytics with smart contact tracing, automated alert messaging for self-restriction, and follow-up of the outcome related to COVID-19 using health insurance data could curtail the resources required for conventional epidemiological contact tracing.


Asunto(s)
Macrodatos , Trazado de Contacto/métodos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/prevención & control , Brotes de Enfermedades/prevención & control , Pandemias/prevención & control , Neumonía Viral/diagnóstico , Neumonía Viral/prevención & control , Vigilancia en Salud Pública/métodos , Cuarentena/métodos , Navíos , Betacoronavirus/aislamiento & purificación , COVID-19 , Control de Enfermedades Transmisibles , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Brotes de Enfermedades/estadística & datos numéricos , Sistemas de Información Geográfica , Humanos , Pandemias/estadística & datos numéricos , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Estudios Retrospectivos , SARS-CoV-2 , Taiwán/epidemiología
10.
J Formos Med Assoc ; 119(5): 925-932, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32057544

RESUMEN

BACKGROUND/PURPOSE: Few studies exist investigating the effectiveness of radioiodine (RAI) therapy for hyperthyroidism patients in Asia. We herein investigated the real-world efficacy of single-dose RAI therapy in Taiwanese patients with Graves' disease (GD). METHODS: This is a retrospective study of 243 patients with GD recorded between 1989 and 2016 in a tertiary referral hospital. Eu- or hypothyroid after RAI therapy were defined as the successful group. Kaplan-Meier curve and cox-regression model were used for analysis of prognostic factors. RESULTS: Of the 243 patients, 187 were females, with mean age of 46.9 ± 13.6 years. Most patients (63.8%) did not choose RAI as the first-line therapy. The median dose was 7 mCi, with a mean follow-up period of 107.1 ± 82.8 months. The overall success rate was 70.9%. Univariate analysis revealed calculated- or fixed-dose (P = 0.015), goiter size (P < 0.001), and RAI dose (P = 0.022) were the factors affecting RAI effectiveness, multivariate analysis indicated goiter size was the independent factor. Patients with grade 0-2 goiter had a higher success rate than patients with grade 3 goiter (HR = 2.1, 95%CI = 1.34-3.27, P = 0.001), although the former were treated with lower RAI dose than the latter (7.8 ± 3.2 mCi vs 8.8 ± 3.3 mCi, P = 0.049). However, if the grade 3 goiters became smaller within 3 months of therapy, the success rate was not inferior to grade 0-2 goiter. CONCLUSION: In Taiwan, RAI therapy for GD patients reached an overall success rate of 70.9%, with a median dose of 7 mCi. This study identified patients with grade 3 goiter need a more aggressive RAI regimen.


Asunto(s)
Enfermedad de Graves , Radioisótopos de Yodo , Adulto , Asia , Femenino , Enfermedad de Graves/radioterapia , Humanos , Radioisótopos de Yodo/uso terapéutico , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Taiwán , Resultado del Tratamiento
11.
Acta Pharmacol Sin ; 40(8): 1106-1118, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30792487

RESUMEN

Cinnamic acid and its analogues (pyragrel and ozagrel) undergo chain-shortened (ß-oxidative) and reductive metabolism on acyl side chain. In this study, we characterized the ß-oxidative and reductive metabolism on acyl side chain of cinnamic acid and its analogues using primary rat hepatocytes, hepatic mitochondrial, and microsomal systems. A compartmental model including parent compounds and metabolites was developed to characterize in vivo ß-oxidative and reductive metabolism following an intravenous dose of parent compounds to rats. The fitted total in vivo clearance values were further compared with the in vitro values predicted by the well-stirred model. We showed that hepatic microsomal CYP450s did not catalyze ß-oxidative or reductive metabolism of the three compounds. Similar to ß-oxidation of fatty acids, ß-oxidative metabolism on their acyl side chain occurred mainly in mitochondria, which was highly dependent on ATP, CoA and NAD+. Fatty acids and NADH inhibited the ß-oxidative metabolism. Reductive metabolism occurred in both mitochondria and microsomes. Reduction in mitochondria was ATP-, CoA-, and NAD(P)H-dependent and reversible, which was suppressed by enoyl reductase inhibitor triclosan. Reduction in microsomes was ATP-, CoA-, and NADPH-dependent but little affected by triclosan. Both plasma concentrations of ß-oxidative metabolites and reductive metabolites were successfully fitted using the compartmental model. The estimated total in vivo clearance values were consistent with those predicted from hepatocytes and organelles, implicating significance of in vitro kinetics. These findings demonstrate the roles of hepatic mitochondria and microsomes in ß-oxidative and reductive metabolism on acyl side chain of cinnamic acid and its analogues along with their metabolic characteristics.


Asunto(s)
Cinamatos/metabolismo , Metacrilatos/metabolismo , Pirazinas/metabolismo , Animales , Cinamatos/química , Cinamatos/farmacocinética , Ácidos Grasos/metabolismo , Hepatocitos/metabolismo , Masculino , Metacrilatos/química , Metacrilatos/farmacocinética , Microsomas Hepáticos/metabolismo , Mitocondrias Hepáticas/metabolismo , Estructura Molecular , NAD/metabolismo , Oxidación-Reducción/efectos de los fármacos , Pirazinas/química , Pirazinas/farmacocinética , Ratas Sprague-Dawley , Triclosán/farmacología
12.
Proc Natl Acad Sci U S A ; 112(34): 10798-803, 2015 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-26261348

RESUMEN

Acute hepatopancreatic necrosis disease (AHPND) is a severe, newly emergent penaeid shrimp disease caused by Vibrio parahaemolyticus that has already led to tremendous losses in the cultured shrimp industry. Until now, its disease-causing mechanism has remained unclear. Here we show that an AHPND-causing strain of V. parahaemolyticus contains a 70-kbp plasmid (pVA1) with a postsegregational killing system, and that the ability to cause disease is abolished by the natural absence or experimental deletion of the plasmid-encoded homologs of the Photorhabdus insect-related (Pir) toxins PirA and PirB. We determined the crystal structure of the V. parahaemolyticus PirA and PirB (PirA(vp) and PirB(vp)) proteins and found that the overall structural topology of PirA(vp)/PirB(vp) is very similar to that of the Bacillus Cry insecticidal toxin-like proteins, despite the low sequence identity (<10%). This structural similarity suggests that the putative PirAB(vp) heterodimer might emulate the functional domains of the Cry protein, and in particular its pore-forming activity. The gene organization of pVA1 further suggested that pirAB(vp) may be lost or acquired by horizontal gene transfer via transposition or homologous recombination.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Toxinas Bacterianas/aislamiento & purificación , Plásmidos/metabolismo , Vibrio parahaemolyticus/patogenicidad , Animales , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Conjugación Genética , ADN Bacteriano/genética , Genes Bacterianos , Modelos Moleculares , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Penaeidae/microbiología , Plásmidos/genética , Porinas/química , Conformación Proteica , Homología de Secuencia de Ácido Nucleico , Vibrio parahaemolyticus/genética , Virulencia/genética
13.
J Biol Chem ; 291(37): 19312-23, 2016 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-27458021

RESUMEN

Puf6 and Loc1 have two important functional roles in the cells, asymmetric mRNA distribution and ribosome biogenesis. Puf6 and Loc1 are localized predominantly in the nucleolus. They bind ASH1 mRNA, repress its translation, and facilitate the transport to the daughter cells. Asymmetric mRNA distribution is important for cell differentiation. Besides their roles in mRNA localization, Puf6 and Loc1 have been shown to be involved in 60S biogenesis. In puf6Δ or loc1Δ cells, pre-rRNA processing and 60S export are impaired and 60S subunits are underaccumulated. The functional studies of Puf6 and Loc1 have been focused on ASH1 mRNA pathway, but their roles in 60S biogenesis are still not clear. In this study, we found that Puf6 and Loc1 interact directly with each other and both proteins interact with the ribosomal protein Rpl43 (L43e). Notably, the roles of Puf6 and Loc1 in 60S biogenesis are interdependent, and both are required for efficient accommodation of Rpl43. Loc1 is further required to maintain the protein level of Rpl43. Additionally, the recruitment of Rpl43 is required for the release of Puf6 and Loc1. We propose that Puf6 and Loc1 facilitate Rpl43 loading and are sequentially released from 60S after incorporation of Rpl43 into ribosomes in yeast.


Asunto(s)
Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas Grandes de Eucariotas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Nucleares/genética , Proteínas de Unión al ARN/genética , Proteínas Ribosómicas/genética , Subunidades Ribosómicas Grandes de Eucariotas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
14.
Appl Microbiol Biotechnol ; 100(20): 8889-900, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27470140

RESUMEN

The bean bug, Riptortus pedestris, is a major agricultural pest that reduces crop quality and value. Chemical pesticides have contributed to pest management, but resistance to these chemicals has significantly limited their use. Alternative strategies with different modes of action, such as entomopathogenic fungi, are therefore of great interest. Herein, we explored how entomopathogenic fungi can potentially be used to control the bean bug and focused on identifying virulence-related genes. Beauveria bassiana (JEF isolates) were assayed against bean bugs under laboratory conditions. One isolate, JEF-007, showed >80 % virulence by both spray and contact exposure methods. Agrobacterium tumefaciens-mediated transformation (AtMT) of JEF-007 generated 249 random transformants, two of which (B1-06 and C1-49) showed significantly reduced virulence against Tenebrio molitor and R. pedestris immatures. Both species were used for rapid screening of virulence-reduced mutants. The two transformants had different morphologies, conidial production, and thermotolerance than the wild type. To determine the localization of the randomly inserted T-DNA, thermal asymmetric interlaced (TAIL) PCR was conducted and analysis of the two clones found multiple T-DNA insertions (two in B1-06 and three in C1-49). Genes encoding complex I intermediate-associated protein 30 (CIA30) and the autophagy protein (Atg22) were possibly disrupted by the T-DNA insertion and might be involved in the virulence. This work provides a strong platform for future functional genetic studies of bean bug-pathogenic B. bassiana. The genes putatively involved in fungal virulence should be experimentally validated by knockdown in future studies.


Asunto(s)
Beauveria/genética , Beauveria/patogenicidad , ADN Bacteriano/genética , Heterópteros/fisiología , Mutagénesis Insercional , Factores de Virulencia/genética , Agrobacterium tumefaciens/genética , Animales , Bioensayo/métodos , Heterópteros/microbiología , Análisis de Supervivencia , Tenebrio/microbiología , Tenebrio/fisiología , Transformación Genética , Virulencia
15.
J Invertebr Pathol ; 141: 57-65, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27840139

RESUMEN

A viral genome was assembled de novo from next-generation sequencing (NGS) data from bean bugs, Riptortus pedestris, infected with an entomopathogenic fungus, Beauveria bassiana (Bb), and was further confirmed via the RACE method. This is a novel insect positive-sense single-stranded RNA virus, which we named Riptortus pedestris virus-1 (RiPV-1) (GenBank accession no. KU958718). The genome of RiPV-1 consists of 10,554 nucleotides (nt), excluding the poly(A) tail, which contains a single large open reading frame (ORF) of 10,371 nt encoding a polyprotein (3456 aa) and flanked by 71 and 112 nt at the 5' and 3' untranslated regions (UTR), respectively. RiPV-1 genome organization from the 5' end contains a consensus organization of picorna-like RNA virus helicase, cysteine protease, and RNA-dependent RNA polymerase (RdRp), in addition to two putative structural proteins located at the 3' region and a poly(A) tail at the 3' end. The viral particles were approximately 30nm in diameter with some dispersal distinctive surface projections. Based on the phylogenetic analysis of the RdRp sequences, RiPV-1 was clustered in the unassigned insect RNA viruses with two other viruses, APV and KFV. These three viruses were suggested to constitute a new group of insect RNA viruses. RiPV-1 could be found in all stages of lab-reared bean bugs and was detected abundantly in the thorax, abdomen, midgut and fat body, but not in the reproductive organs and muscle. Interestingly, RiPV-1 replication was increased dramatically in bean bugs 2-6days after fungal infection. In conclusion, a novel insect RNA virus was found by NGS data assembly. This virus can provide further insight into the interaction between virus, fungus and the host.


Asunto(s)
Coinfección , Heterópteros/virología , Virus de Insectos/genética , Virus ARN/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Beauveria , Genoma Viral , Heterópteros/parasitología , Secuenciación de Nucleótidos de Alto Rendimiento , Micosis/veterinaria , Filogenia , ARN Viral , Alineación de Secuencia
16.
BMC Genomics ; 15: 628, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-25063321

RESUMEN

BACKGROUND: Penaeus monodon nudivirus (PmNV) is the causative agent of spherical baculovirosis in shrimp (Penaeus monodon). This disease causes significant mortalities at the larval stage and early postlarval (PL) stage and may suppress growth and reduce survival and production in aquaculture. The nomenclature and classification status of PmNV has been changed several times due to morphological observation and phylogenetic analysis of its partial genome sequence. In this study, we therefore completed the genome sequence and constructed phylogenetic trees to clarify PmNV's taxonomic position. To better understand the characteristics of the occlusion bodies formed by this marine occluded virus, we also compared the chemical properties of the polyhedrin produced by PmNV and the baculovirus AcMNPV (Autographa californica nucleopolyhedrovirus). RESULTS: We used next generation sequencing and traditional PCR methods to obtain the complete PmNV genome sequence of 119,638 bp encoding 115 putative ORFs. Phylogenetic tree analysis showed that several PmNV genes and sequences clustered with the non-occluded nudiviruses and not with the baculoviruses. We also investigated the characteristics of PmNV polyhedrin, which is a functionally important protein and the major component of the viral OBs (occlusion bodies). We found that both recombinant PmNV polyhedrin and wild-type PmNV OBs were sensitive to acid conditions, but unlike the baculoviral OBs, they were not susceptible to alkali treatment. CONCLUSIONS: From the viral genome features and phylogenetic analysis we conclude that PmNV is not a baculovirus, and that it should be assigned to the proposed Nudiviridae family with the other nudiviruses, but into a distinct new genus (Gammanudivirus).


Asunto(s)
Organismos Acuáticos/virología , Baculoviridae/genética , Baculoviridae/fisiología , Genómica , Penaeidae/virología , Animales , Baculoviridae/clasificación , Baculoviridae/metabolismo , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Genoma Viral/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Datos de Secuencia Molecular , Boca/virología , Sistemas de Lectura Abierta/genética , Filogenia , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Proteínas Virales/genética , Proteínas Virales/metabolismo , Ensamble de Virus/genética
17.
J Virol ; 87(24): 13263-78, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24089551

RESUMEN

Although shrimp white spot syndrome virus (WSSV) is a large double-stranded DNA virus (∼300 kbp), it expresses many polycistronic mRNAs that are likely to use internal ribosome entry site (IRES) elements for translation. A polycistronic mRNA encodes the gene of the highly expressed nonstructural protein ICP35, and here we use a dual-luciferase assay to demonstrate that this protein is translated cap independently by an IRES element located in the 5' untranslated region of icp35. A deletion analysis of this region showed that IRES activity was due to stem-loops VII and VIII. A promoterless assay, a reverse transcription-PCR together with quantitative real-time PCR analysis, and a stable stem-loop insertion upstream of the Renilla luciferase open reading frame were used, respectively, to rule out the possibility that cryptic promoter activity, abnormal splicing, or read-through was contributing to the IRES activity. In addition, a Northern blot analysis was used to confirm that only a single bicistronic mRNA was expressed. The importance of ICP35 to viral replication was demonstrated in a double-stranded RNA (dsRNA) interference knockdown experiment in which the mortality of the icp35 dsRNA group was significantly reduced. Tunicamycin was used to show that the α subunit of eukaryotic initiation factor 2 is required for icp35 IRES activity. We also found that the intercalating drug quinacrine significantly inhibited icp35 IRES activity in vitro and reduced the mortality rate and viral copy number in WSSV-challenged shrimp. Lastly, in Sf9 insect cells, we found that knockdown of the gene for the Spodoptera frugiperda 40S ribosomal protein RPS10 decreased icp35 IRES-regulated firefly luciferase activity but had no effect on cap-dependent translation.


Asunto(s)
Penaeidae/virología , Biosíntesis de Proteínas , Ribosomas/genética , Proteínas no Estructurales Virales/genética , Virus del Síndrome de la Mancha Blanca 1/genética , Regiones no Traducidas 5' , Animales , Regulación Viral de la Expresión Génica , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/genética , ARN Viral/metabolismo , Ribosomas/metabolismo , Proteínas no Estructurales Virales/metabolismo , Virus del Síndrome de la Mancha Blanca 1/metabolismo
18.
Asian J Androl ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38856299

RESUMEN

ABSTRACT: Male infertility is a global issue caused by poor sperm quality, particularly motility. Enhancement of the sperm quality may improve the fertilization rate in assisted reproductive technology (ART) treatment. Scriptaid, with a novel human sperm motility-stimulating activity, has been investigated as a prospective agent for improving sperm quality and fertilization rate in ART. We evaluated the effects of Scriptaid on asthenozoospermic (AZS) semen, including its impact on motility stimulation and protective effects on cryopreservation and duration of motility, by computer-aided sperm analysis (CASA). Sperm quality improvement by Scriptaid was characterized by increased hyaluronan-binding activity, tyrosine phosphorylation, adenosine triphosphate (ATP) concentration, mitochondrial membrane potential, and an ameliorated AZS fertilization rate in clinical intracytoplasmic sperm injection (ICSI) experiments. Furthermore, our identification of active Scriptaid analogs and different metabolites induced by Scriptaid in spermatozoa lays a solid foundation for the future biomechanical exploration of sperm function. In summary, Scriptaid is a potential candidate for the treatment of male infertility in vitro as it improves sperm quality, prolongs sperm viability, and increases the fertilization rate.

19.
Med Eng Phys ; 129: 104189, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38906572

RESUMEN

Understanding the role of mechanical force on tissue nutrient transport is essential, as sustained force may affect nutrient levels within the disc and initiate disc degeneration. This study aims to evaluate the time-dependent effects of different compressive force amplitudes as well as tensile force on glucose concentration and cell viability within the disc. Based on the mechano-electrochemical mixture theory, a multiphasic finite element model of the lumbar intervertebral disc was developed. The minimum glucose concentration and minimum cell density in both normal and degenerated discs were predicted for different compressive force amplitudes, tensile force, and corresponding creep time. Under high compressive force, the minimum glucose concentration exhibited an increasing and then decreasing trend with creep time in the normal disc, whereas that of the degenerated disc increased, then decreased, and finally increased again. At steady state, a higher compressive force was accompanied by a lower glucose concentration distribution. In the degenerated disc, the minimum cell density was negatively correlated with creep time, with a greater range of affected tissue under a higher compressive force. For tensile force, the minimum glucose concentration of the degenerated disc raised over time. This study highlighted the importance of creep time, force magnitude, and force type in affecting nutrient concentration and cell viability. Sustained weight-bearing activities could deteriorate the nutrient environment of the degenerated disc, while tensile force might have a nonnegligible role in effectively improving nutrient levels within the degenerated disc.


Asunto(s)
Supervivencia Celular , Fuerza Compresiva , Análisis de Elementos Finitos , Glucosa , Disco Intervertebral , Resistencia a la Tracción , Glucosa/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/citología , Modelos Biológicos , Fenómenos Biomecánicos , Estrés Mecánico
20.
Med Biol Eng Comput ; 62(4): 1089-1104, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38148413

RESUMEN

Recent studies have emphasized the importance of dynamic activity in the development of myelopathy. However, current knowledge of how degenerative factors affect the spinal cord during motion is still limited. This study aimed to investigate the effect of various types of preexisting herniated cervical disc and the ligamentum flavum ossification on the spinal cord during cervical flexion and extension. A detailed dynamic fluid-structure interaction finite element model of the cervical spine with the spinal cord was developed and validated. The changes of von Mises stress and maximum principal strain within the spinal cord in the period of normal, hyperflexion, and hyperextension were investigated, considering various types and grades of disc herniation and ossification of the ligamentum flavum. The flexion and extension of the cervical spine with spinal canal encroachment induced high stress and strain inside the spinal cord, and this effect was also amplified by increased canal encroachments and cervical hypermobility. The spinal cord might evade lateral encroachment, leading to a reduction in the maximum stress and principal strain within the spinal cord in local-type herniation. Although the impact was limited in the case of diffuse type, the maximum stress tended to appear in the white matter near the encroachment site while compression from both ventral and dorsal was essential to make maximum stress appear in the grey matter. The existence of canal encroachment can reduce the safe range for spinal cord activities, and hypermobility activities may induce spinal cord injury. Besides, the ligamentum flavum plays an important role in the development of central canal syndrome.Significance. This model will enable researchers to have a better understanding of the influence of cervical degenerative diseases on the spinal cord during extension and flexion.


Asunto(s)
Cuello , Médula Espinal , Análisis de Elementos Finitos , Vértebras Cervicales , Osteogénesis
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