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1.
J Org Chem ; 89(7): 4619-4627, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38536672

RESUMEN

Allyl sulfones are commonly present in bioactive compounds and organic building blocks. This work introduces a photocatalytic radical addition-elimination reaction involving readily accessible sulfonyl chlorides and allyl bromides. It delivers structurally diverse allylic sulfones in moderate to excellent yields, showcasing a high tolerance to functional groups. Notably, this method operates under mild reaction conditions without the need for oxidants, stoichiometric reducing metals, or additives.

2.
Int Dent J ; 74(1): 102-109, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37714716

RESUMEN

OBJECTIVES: This study aimed to explore the influence of alveolar bone morphologic variables on the outcome of guided bone regeneration (GBR) in the anterior maxilla region. METHODS: Twenty-eight patients who received single maxillary anterior tooth delayed implant placed simultaneously with GBR were recruited. Baseline data including age, gender, implant site, implant brand, and bone graft materials were recorded. The resorption rate of the grafted bone (RRGB), labial bone width at 0 mm, 2 mm, and 4 mm apical to the implant platform at Tn (LBW0Tn, LBW2Tn, LBW4Tn), implant angulation (IA), maximum bone graft thickness (MBGT), bone graft volume (BGV), and the initial bone morphologic variables bone concavity depth (BCD) and bone concavity angulation (BCA) were measured. The Pearson correlation analysis, analysis of variance (ANOVA), and optimal binning method were used to explore the potential predictors for GBR. RESULTS: Among 28 patients, the labial bone width of implant and bone graft volume decreased significantly when measured 6 months after surgery. The mean percentage of RRGB was 49.78%. RRGB was not correlated with gender, age, bone graft material, IA, MBGT, bone graft volume at T1, implant site, and implant brand (P > .05). BCD and BCA were each moderately correlated with RRGB (r = -0.872 [P < .001] and r = 0.686 [P < .001], respectively). A BCD ≥1.03 mm and a BCA <155.30° resulted in a significantly lower percentage of RRGB (P < .001). CONCLUSIONS: A significant grafted bone materials volume reduction was detected after GBR with collagen membrane and deproteinized bovine bone mineral (DBBM). The initial bone morphology can influence GBR outcome, and a bone concavity with a depth ≥1.03 mm and an angulation <155.30° led to a lower RRGB. BCD and BCA can be used as variables to predict the outcome of GBR.


Asunto(s)
Aumento de la Cresta Alveolar , Implantes Dentales , Humanos , Animales , Bovinos , Maxilar/cirugía , Aumento de la Cresta Alveolar/métodos , Regeneración Ósea , Colágeno , Trasplante Óseo/métodos
3.
J Org Chem ; 88(1): 329-340, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36563045

RESUMEN

Diaryl alcohol moieties are widespread in pharmaceuticals. Existing methods for the synthesis of diaryl alcohols require the use of pre-functionalized benzylic alcohols, aromatic aldehydes, or ketones as starting materials. Herein, the first convergent paired electrochemical approach to the direct hydroxylarylation of unactivated benzylic carbons (sp3/sp2/sp) is proposed. This protocol features direct functionalization of unactivated benzylic C(sp3)-H bonds and benzylic sp2/sp-carbons, mild conditions (open air, room temperature), an environmentally friendly procedure (without any external catalyst/mediator/additive), and direct access to sterically hindered alcohols from inexpensive and readily available alkyl/alkenyl/alkynylbenzenes. Mechanistic studies, including divided-cell experiments, isotope labeling, radical trapping, electron paramagnetic resonance, reaction kinetics, and cyclic voltammetry, strongly support the proposed radical-radical cross-coupling between transient ketyl radicals and persistent radical anions. Gram-scale synthesis and diversification of drug derivatives have visualized the tremendous potential of this protocol for practical applications.


Asunto(s)
Aldehídos , Alcohol Bencilo , Carbono/química , Etanol , Catálisis
4.
Arch Med Sci ; 18(6): 1716-1717, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457961
5.
Scand J Immunol ; 96(3): e13191, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35538715

RESUMEN

The present study focuses on the associations of serum immunoglobulin with disease activity, relapse/recurrence and renal involvement in Henoch-Schönlein purpura (HSP) children. 1683 Chinese children with HSP were recruited from January 2015 to January 2021. Laboratory data of blood samples and urine tests were collected. Renal biopsy was performed by the percutaneous technique. Patients' histories associated with HSP onset were obtained by interviews and questionnaires. (1) IgA and IgE were dramatically elevated in HSP patients as compared to their normal values and subject to a 1.75-3.09 fold and a 1.97-2.61 fold increase, respectively. (2) No significant correlation of the disease activity with IgA and IgE was determined, respectively. (3) The serum IgA levels were significantly lower in patients with relapse/recurrence than that in patients without relapse/recurrence, which may be attributed to the transmission of IgA-mediated immune complexes from blood to vessel walls. (4) No significant correlation was found between serum IgA, IgE levels and the pathological classification. HSP children have marked disorders of serum immunoglobulin profiles, characterized by significant increases in IgA and IgE. The detection of serum IgA may be applicable to predict relapse/recurrence of HSP whereas not associated with disease activity and renal involvement.


Asunto(s)
Vasculitis por IgA , Niño , China , Humanos , Inmunoglobulina A , Inmunoglobulina E , Recurrencia
8.
Pediatr Res ; 92(1): 275-283, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34584222

RESUMEN

BACKGROUND: In China, coronary artery abnormalities (CAAs) secondary to Kawasaki disease (KD) tend to have an increased occurrence. We hypothesize that Chinese children with KD may possess several unique CAA risks, and the predictive efficacy of multiple scoring systems in Chinese patients are still to be further studied. METHODS: Two hundred and three KD patients were recruited. Using multivariable analysis, independent predictors of CAAs were combined into a scoring system. Subsequently, CAA risks of our patients were evaluated by the newly established scoring system and eight other published scoring systems. RESULTS: Seventeen (8.37%) KD patients were identified as CAAs. The newly established scoring system contained the following 5 independent predictors: days of illness at initial treatment ≥7, redness and swelling of extremities, hematocrit ≤33%, percentage of monocytes ≥8.89%, and procalcitonin ≥0.5 ng/mL. The AUC value of newly established scoring system was 0.685 with a sensitivity of 41.18% and a specificity of 84.41%, higher than Harada score, Egami score, Kobayashi score, Sato score, San Diego score, Formosa score, and Tang score, whereas lower than Hua score. CONCLUSIONS: Days of illness at initial treatment ≥7 and procalcitonin are unique predictors of CAAs in newly established scoring system. Taking into account different identification criteria and analytical methodologies, there is still some heterogeneity among different scoring systems. IMPACT: The newly established scoring system contains the five independent predictors. Days of illness at initial treatment ≥7 and PCT are unique predictors of CAAs in our study, compared with 8 other systems. The AUC value of newly established scoring system is 0.685, similar to Hua score. There is some heterogeneity among different scoring systems.


Asunto(s)
Enfermedad de la Arteria Coronaria , Cardiopatías Congénitas , Síndrome Mucocutáneo Linfonodular , Enfermedad de la Arteria Coronaria/complicaciones , Cardiopatías Congénitas/complicaciones , Humanos , Inmunoglobulinas Intravenosas , Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/diagnóstico , Polipéptido alfa Relacionado con Calcitonina , Estudios Retrospectivos
10.
Front Cell Neurosci ; 15: 732602, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34512271

RESUMEN

Chronic alcohol consumption causes cognitive impairments accompanying with white matter atrophy. Recent evidence has shown that myelin dynamics remain active and are important for brain functions in adulthood. For example, new myelin generation is required for learning and memory functions. However, it remains undetermined whether alcohol exposure can alter myelin dynamics in adulthood. In this study, we examine the effect of chronic alcohol exposure on myelin dynamics by using genetic approaches to label newly generated myelin (NG2-CreERt; mT/mG). Our results indicated that alcohol exposure (either 5% or 10% in drinking water) for 3 weeks remarkably reduced mGFP + /NG2- new myelin and mGFP + /CC1 + new oligodendrocytes in the prefrontal cortex and corpus callosum of 6-month-old NG2-CreERt; mT/mG mice as compared to controls without changing the mGFP + /NG2 + oligodendrocyte precursor cells (OPCs) density, suggesting that alcohol exposure may inhibit oligodendrocyte differentiation. In support with these findings, the alcohol exposure did not significantly alter apoptotic cell number or overall MBP expression in the brains. Further, the alcohol exposure decreased the histone deacetylase1 (HDAC1) expression in mGFP + /NG2 + OPCs, implying epigenetic mechanisms were involved in the arrested OPC differentiation. Together, our results indicate that chronic exposure to alcohol can inhibit myelinogenesis in the adult mouse brain and that may contribute to alcohol-related cognitive impairments.

11.
Neurosci Bull ; 37(10): 1397-1411, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34292513

RESUMEN

Exposure to chronic hypoxia is considered to be a risk factor for deficits in brain function in adults, but the underlying mechanisms remain largely unknown. Since active myelinogenesis persists in the adult central nervous system, here we aimed to investigate the impact of chronic hypoxia on myelination and the related functional consequences in adult mice. Using a transgenic approach to label newly-generated myelin sheaths (NG2-CreERTM; Tau-mGFP), we found that myelinogenesis was highly active in most brain regions, such as the motor cortex and corpus callosum. After exposure to hypoxia (10% oxygen) 12 h per day for 4 weeks, myelinogenesis was largely inhibited in the 4-month old brain and the mice displayed motor coordination deficits revealed by the beam-walking test. To determine the relationship between the inhibited myelination and functional impairment, we induced oligodendroglia-specific deletion of the transcription factor Olig2 by tamoxifen (NG2-CreERTM; Tau-mGFP; Olig2 fl/fl) in adult mice to mimic the decreased myelinogenesis caused by hypoxia. The deletion of Olig2 inhibited myelinogenesis and consequently impaired motor coordination, suggesting that myelinogenesis is required for motor function in adult mice. To understand whether enhancing myelination could protect brain functions against hypoxia, we treated hypoxic mice with the myelination-enhancing drug-clemastine, which resulted in enhanced myelogenesis and improved motor coordination. Taken together, our data indicate that chronic hypoxia inhibits myelinogenesis and causes functional deficits in the brain and that enhancing myelinogenesis protects brain functions against hypoxia-related deficits.


Asunto(s)
Vaina de Mielina , Oligodendroglía , Animales , Clemastina , Hipoxia/complicaciones , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
12.
Neuron ; 109(14): 2292-2307.e5, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34102111

RESUMEN

Severe cognitive decline is a hallmark of Alzheimer's disease (AD). In addition to gray matter loss, significant white matter pathology has been identified in AD patients. Here, we characterized the dynamics of myelin generation and loss in the APP/PS1 mouse model of AD. Unexpectedly, we observed a dramatic increase in the rate of new myelin formation in APP/PS1 mice, reminiscent of the robust oligodendroglial response to demyelination. Despite this increase, overall levels of myelination are decreased in the cortex and hippocampus of APP/PS1 mice and postmortem AD tissue. Genetically or pharmacologically enhancing myelin renewal, by oligodendroglial deletion of the muscarinic M1 receptor or systemic administration of the pro-myelinating drug clemastine, improved the performance of APP/PS1 mice in memory-related tasks and increased hippocampal sharp wave ripples. Taken together, these results demonstrate the potential of enhancing myelination as a therapeutic strategy to alleviate AD-related cognitive impairment.


Asunto(s)
Enfermedad de Alzheimer/patología , Disfunción Cognitiva/patología , Aprendizaje por Laberinto/fisiología , Vaina de Mielina/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Modelos Animales de Enfermedad , Ratones , Ratones Transgénicos , Vaina de Mielina/genética , Vaina de Mielina/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo
13.
Neurosci Bull ; 37(8): 1135-1146, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34106403

RESUMEN

Increasing evidence has shown that astrocytes are implicated in regulating oligodendrocyte myelination, but the underlying mechanisms remain largely unknown. To understand whether microRNAs in astrocytes function in regulating oligodendroglial differentiation and myelination in the developing and adult CNS, we generated inducible astrocyte-specific Dicer conditional knockout mice (hGFAP-CreERT; Dicer fl/fl). By using a reporter mouse line (mT/mG), we confirmed that hGFAP-CreERT drives an efficient and astrocyte-specific recombination in the developing CNS, upon tamoxifen treatment from postnatal day 3 (P3) to P7. The Dicer deletion in astrocytes resulted in inhibited oligodendroglial differentiation and myelination in the developing CNS of Dicer cKO mice at P10 and P14, and did not alter the densities of neurons or axons, indicating that Dicer in astrocytes is required for oligodendrocyte myelination. Consequently, the Dicer deletion in astrocytes at P3 resulted in impaired spatial memory and motor coordination at the age of 9 weeks. To understand whether Dicer in astrocytes is also required for remyelination, we induced Dicer deletion in 3-month-old mice and then injected lysolecithin into the corpus callosum to induce demyelination. The Dicer deletion in astrocytes blocked remyelination in the corpus callosum 14 days after induced demyelination. Together, our results indicate that Dicer in astrocytes is required for oligodendroglia myelination in both the developing and adult CNS.


Asunto(s)
Diferenciación Celular , ARN Helicasas DEAD-box/genética , Vaina de Mielina , Oligodendroglía/citología , Remielinización , Ribonucleasa III/genética , Animales , Astrocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neurogénesis
14.
Pediatr Rheumatol Online J ; 19(1): 79, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34078391

RESUMEN

BACKGROUND: The present study focuses on the associations of streptococcal infection with the clinical phenotypes, relapse/recurrence and renal involvement in Henoch-Schönlein purpura (HSP) children. METHODS: Two thousand seventy-four Chinese children with HSP were recruited from January 2015 to December 2019. Patients' histories associated with HSP onset were obtained by interviews and questionnaires. Laboratory data of urine tests, blood sample and infectious agents were collected. Renal biopsy was performed by the percutaneous technique. RESULTS: (1) Streptococcal infection was identified in 393 (18.9%) HSP patients, and served as the most frequent infectious trigger. (2) Among the 393 cases with streptococcal infection, 43.0% of them had arthritis/arthralgia, 32.1% had abdominal pain and 29.3% had renal involvement. (3) 26.1% of HSP patients relapsed or recurred more than 1 time within a 5-year observational period, and the relapse/recurrence rate in streptococcal infectious group was subjected to a 0.4-fold decrease as compared with the non-infectious group. (4) No significant differences in renal pathological damage were identified among the streptococcal infectious group, the other infectious group and the non-infectious group. CONCLUSIONS: Streptococcal infection is the most frequent trigger for childhood HSP and does not aggravate renal pathological damage; the possible elimination of streptococcal infection helps relieve the relapse/recurrence of HSP.


Asunto(s)
Artritis , Vasculitis por IgA , Enfermedades Renales , Infecciones Estreptocócicas , Streptococcus , Artritis/diagnóstico , Artritis/etiología , Artritis/inmunología , Biopsia/métodos , Biopsia/estadística & datos numéricos , Niño , China/epidemiología , Correlación de Datos , Femenino , Humanos , Vasculitis por IgA/diagnóstico , Vasculitis por IgA/epidemiología , Vasculitis por IgA/microbiología , Vasculitis por IgA/fisiopatología , Inmunoglobulina A/análisis , Enfermedades Renales/diagnóstico , Enfermedades Renales/etiología , Enfermedades Renales/inmunología , Glomérulos Renales/patología , Masculino , Recurrencia , Estudios Retrospectivos , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/fisiopatología , Streptococcus/inmunología , Streptococcus/aislamiento & purificación
15.
Clin Exp Med ; 21(4): 633-643, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33839960

RESUMEN

OBJECTIVE: Kawasaki disease (KD) is an acute systemic vasculitis and suspected to be triggered by several potential infections in which procalcitonin (PCT) experiences an increase to some extent. However, whether PCT can serve as a useful candidate for differentiating KD from sepsis, and even for predicting incomplete KD, intravenous immunoglobulin (IVIG) nonresponsiveness and coronary artery abnormalities (CAAs) remains unclear. METHODS: A total of 254 Chinese KD children were enrolled and divided into 6 subgroups, including complete KD, incomplete KD, IVIG-responsive KD, IVIG-nonresponsive KD, KD with CAAs and KD without CAAs. Blood samples were collected from all subjects within 24-h pre- and 48-h post-IVIG infusion, respectively. PCT, C-reactive protein, erythrocyte sedimentation rate and blood cell counts were detected. In addition, both 261 children with sepsis and 251 healthy children sex- and age-matched with KD children were enrolled in the same period. RESULTS: (1) PCT experienced the highest increase in sepsis patients before antibiotic therapy, followed by acute KD patients and the healthy controls. (2) The proportion of KD patients with a PCT concentration below 0.25 ng/ml was 11 folds higher than that of sepsis patients. (3) PCT had a sensitivity of 91.7% and a specificity of 30.3% at a cutoff value of > 0.15 ng/ml to predict IVIG nonresponsiveness, and the proportion of IVIG-nonresponders with a PCT concentration of 0.25-0.50 ng/ml was 2 folds higher than that of IVIG-responders. CONCLUSIONS: The PCT concentrations below 0.25 ng/ml may be useful for discriminating KD from sepsis, and moreover, the PCT concentrations of 0.25-0.50 ng/ml may be helpful in predicting IVIG nonresponsiveness.


Asunto(s)
Síndrome Mucocutáneo Linfonodular , Sepsis , Sedimentación Sanguínea , Humanos , Inmunoglobulinas Intravenosas , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Polipéptido alfa Relacionado con Calcitonina , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico
16.
Adv Med Sci ; 66(1): 206-214, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33735829

RESUMEN

PURPOSE: Several studies have demonstrated that C-type natriuretic peptide (CNP) stimulates osteoblastic proliferation seemly via antagonizing the expression of fibroblast growth factor (FGF)-23 in vitro. The main aim of the present study is to probe whether the post-receptor pathways of FGF-23 participate in osteogenesis caused by CNP. METHODS: Osteoblasts were cultured in the absence or presence of CNP: 0, 10, and 100 â€‹pmol/L, for 24 â€‹h, 48 â€‹h and 72 â€‹h, respectively. RESULTS: The findings of the present study indicated that osteoblastic proliferation was directly promoted by exogenous CNP in a dose-dependent manner; osteoblastic FGF-23 was significantly down-regulated by CNP at 24 â€‹h post-treatment; RAF-1, extracellular signal-regulated kinases (ERK), and P38 were substantially suppressed by CNP in a dose- and time-dependent manner; and signal transducer and activator of transcription (STAT)-1 was not changed on the premise of the down-regulated FGF-23 in osteoblasts treated with CNP. CONCLUSION: CNP may promote osteogenesis via inhibiting ERK and P38, rather than STAT-1, in the downstream of FGF-23/RAF-1 pathway.


Asunto(s)
Factores de Crecimiento de Fibroblastos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Natriuréticos/farmacología , Péptido Natriurético Tipo-C/farmacología , Osteoblastos/citología , Osteogénesis , Proteínas Proto-Oncogénicas c-raf/metabolismo , Animales , Factores de Crecimiento de Fibroblastos/genética , Masculino , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Proteínas Proto-Oncogénicas c-raf/genética , Ratas , Ratas Sprague-Dawley , Transducción de Señal
17.
Phys Chem Chem Phys ; 23(4): 2753-2761, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33471019

RESUMEN

Zigzag-edged graphene nanoribbons (ZGNRs) have important applications in spintronics and spin caloritronics. While in the preparation of a ZGNR, defects like the graphene nanobubbles often appear, which may affect the physical properties of the ZGNR. In this paper, we studied the transport properties of a defected ZGNR with a graphene nanobubble by performing first-principles quantum transport calculations. The results show that when the nanobubble is intact and locates at the centre, the spin polarization and magnetoresistance tend to drop off in the low bias voltage cases, compared to the ideal ZGNR. While when the nanobubble is split and locates at the edge, all the transport properties are significantly affected and altered, such as the spin polarization, the giant magnetoresistance effect and the spin Seebeck effect. Meanwhile, some new results are obtained from the device, including the negative differential resistance effect and the pure thermal-induced spin-current.

18.
Eur J Clin Invest ; 51(3): e13409, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32916764

RESUMEN

BACKGROUND: Accurate classification of coronary artery abnormalities (CAAs) is essential for clinical decision-making and long-term management in Kawasaki disease (KD) patients. To date, there are several echocardiographic criteria of CAA assessment. MATERIALS AND METHODS: The Japanese Ministry of Health (JMH) criteria and the Z-score criteria from 2004 American Heart Association guidelines were adopted and their detective efficacies for CAAs were compared in 251 Chinese patients with KD Z scores were calculated by 6 published methods. RESULTS: According to the JMH criteria, 19 (7.57%) KD patients were classified as CAAs during the acute KD episode. However, the detective number of CAAs was highest and had a 0.68-fold increase by the Dallaire et al method with a Z-score cut point of ≥2.5 as compared with the JMH criteria; in contrast, more than 78.95% of patients with CAAs identified by the JMH criteria had a coronary artery Z score ≥2.5. All 6 different Z-score methods had satisfactory accuracies with a range from 93.23% to 97.61% in screening CAAs. For the 19 patients with CAAs identified by the JMH criteria, their Z scores presented the widest variation calculated by the McCrindle et al method. CONCLUSIONS: The JMH criteria underestimate the prevalence of CAAs as compared with the Z-score criteria. Quantitative assessment of coronary artery luminal dimensions, normalized as Z scores adjusted for body surface, should be recommended. The larger coronary artery luminal dimensions vary, the more heterogeneous Z scores calculated by different methods have.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Síndrome Mucocutáneo Linfonodular/diagnóstico por imagen , Preescolar , China , Enfermedad de la Arteria Coronaria/diagnóstico , Ecocardiografía , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Factores Inmunológicos/uso terapéutico , Lactante , Masculino , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos
19.
Asian J Androl ; 23(1): 91-96, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32567578

RESUMEN

Slow freezing is the most commonly used technique for the cryopreservation of spermatozoa in clinical practice. However, it has been shown to have a negative impact on sperm function and structure. Vitrification as a successful alternative method has been proved to have better protective effects on human embryos, but vitrification of spermatozoa is still subject to low recovery rates. In this study, a modified vitrification method for native spermatozoa was developed. A total of 28 semen samples were included; each sample was divided into three equal parts and assigned to fresh, slow freezing, and vitrification groups. Sperm vitality, motility, morphology, DNA integrity, and acrosome reaction were assessed for each of the groups. The results showed that vitrification achieves better results for several sperm protection parameters than slow freezing; vitrification achieves a higher recovery rate (P < 0.05), motility (P <0.05), morphology (P <0.05), and curve line velocity (P <0.05) than slow freezing. Furthermore, DNA fragmentation was decreased (P <0.05) and better acrosome protection (P <0.05) was exhibited in the spermatozoa after vitrification. Principal component analysis of all sperm parameters revealed that the vitrification cluster was closer to the fresh cluster, indicating that spermatozoa are better preserved through vitrification. In conclusion, while both slow freezing and vitrification have negative effects on sperm function and structure, the vitrification protocol described here had a relatively better recovery rate (65.8%) and showed improved preservation of several sperm quality parameters compared with slow freezing.


Asunto(s)
Criopreservación/métodos , Espermatozoides , Vitrificación , Reacción Acrosómica , Adulto , Humanos , Masculino , Manejo de Especímenes/métodos , Motilidad Espermática , Adulto Joven
20.
Pediatr Rheumatol Online J ; 18(1): 46, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32517762

RESUMEN

BACKGROUND: The effects of C-type natriuretic peptide (CNP) and fibroblast growth factor (FGF)-23 appear to oppose each other during the process of bone formation, whereas few studies exist on the interaction between CNP and FGF-23. The main objective of the present study is to probe whether CNP is directly responsible for the regulation of osteoblast or via antagonizing FGF-23. METHODS: Osteoblasts were cultured in the absence or presence of CNP (0, 10, and 100 pmol/L) for 24 h, 48 h and 72 h, respectively. RESULTS: The findings of the present study indicated that: (1) CNP significantly stimulated osteoblastic proliferation and collagen (Col)-X expression; (2) both osteoblastic (osteocalcin, procollagen type I carboxy-terminal propeptide, total alkaline phosphatase and bone-specific alkaline phosphatase) and osteolytic (tartrate-resistant acid phosphatase and cross-linked carboxyterminal telopeptide of type I collagen) bone turnover biomarkers were up-regulated by CNP in osteoblasts; (3) FGF-23 mRNA and protein were significantly down-regulated at 24 h by CNP in osteoblasts, but the expression of FGF receptor-1/Klotho had no significant change. CONCLUSIONS: CNP stimulates osteoblastic proliferation and Col-X expression via the down-regulation of FGF-23 possibly in vitro. However, the specific mechanisms of the interaction between CNP and FGF-23 in osteoblasts are still unclear according to our findings. A further study on osteoblasts cultured with CNP and FGF-23 inhibitor will be undertaken in our laboratory.


Asunto(s)
Proliferación Celular/genética , Factores de Crecimiento de Fibroblastos/genética , Péptido Natriurético Tipo-C/metabolismo , Osteoblastos/metabolismo , Fosfatasa Alcalina/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Animales , Western Blotting , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/genética , Proliferación Celular/efectos de los fármacos , Colágeno Tipo I/efectos de los fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo X/efectos de los fármacos , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Ensayo de Inmunoadsorción Enzimática , Factores de Crecimiento de Fibroblastos/efectos de los fármacos , Factores de Crecimiento de Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Expresión Génica , Regulación de la Expresión Génica , Glucuronidasa/efectos de los fármacos , Glucuronidasa/genética , Glucuronidasa/metabolismo , Técnicas In Vitro , Proteínas Klotho , Péptido Natriurético Tipo-C/farmacología , Osteoblastos/efectos de los fármacos , Osteocalcina/efectos de los fármacos , Osteocalcina/metabolismo , Osteogénesis/genética , Fragmentos de Péptidos/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Cultivo Primario de Células , Procolágeno/efectos de los fármacos , Procolágeno/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/efectos de los fármacos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Fosfatasa Ácida Tartratorresistente/efectos de los fármacos , Fosfatasa Ácida Tartratorresistente/metabolismo
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