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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(5): 512-516, 2024 May 09.
Artigo em Chinês | MEDLINE | ID: mdl-38637007

RESUMO

Regional odontodysplasia (ROD) is a rare localized dental developmental anomaly. The typical clinical manifestations of ROD are abnormal tooth eruption, abnormal development of enamel and dentin. The radiographic characteristic is "ghost teeth". Its etiology still remains unknown. The care and treatment of a patient with ROD needs a multidisciplinary approach. And the treatment should be taken after the assessment of each individual case of ROD. This paper reviews the definition, etiology, epidemiological features, clinical manifestations, imaging features, dental microstructure and treatment strategies of ROD to provide reference for clinical diagnosis and treatment.


Assuntos
Odontodisplasia , Humanos , Esmalte Dentário/anormalidades , Dentina/anormalidades , Erupção Dentária
2.
Nat Commun ; 14(1): 7756, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012200

RESUMO

Two-dimensional (2D) materials offer a prospect of membranes that combine negligible gas permeability with high proton conductivity and could outperform the existing proton exchange membranes used in various applications including fuel cells. Graphene oxide (GO), a well-known 2D material, facilitates rapid proton transport along its basal plane but proton conductivity across it remains unknown. It is also often presumed that individual GO monolayers contain a large density of nanoscale pinholes that lead to considerable gas leakage across the GO basal plane. Here we show that relatively large, micrometer-scale areas of monolayer GO are impermeable to gases, including helium, while exhibiting proton conductivity through the basal plane which is nearly two orders of magnitude higher than that of graphene. These findings provide insights into the key properties of GO and demonstrate that chemical functionalization of 2D crystals can be utilized to enhance their proton transparency without compromising gas impermeability.

3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 58(11): 1123-1131, 2023 Oct 26.
Artigo em Chinês | MEDLINE | ID: mdl-37885183

RESUMO

Objective: To analyze the oral phenotype and gene variation of children with hypophosphatasia (HPP), and explore the genotype-phenotype correlations. Methods: Eight children diagnosed with HPP from January 2008 to January 2023 in Children's Hospital,Zhejiang University School of Medicine were recruited in this study. The pathogenic genes of 5 of them were sequentially analyzed and all of their oral manifestations, laboratory tests and genetic variation types were retrospectively analyzed. Results: A total of 8 children were recruited in the study, 3 males and 5 females, aged from 20 months to 104 months, whose main complaints were premature deciduous tooth loss. Among them, 3 children were diagnosed with odonto HPP, and the other 5 children were diagnosed with childhood HPP, including 2 children was odonto HPP at the first diagnosis and modified as childhood HPP at the age of 5. The age range of first deciduous tooth loss is 9 to 18 months, and the age range of diagnosis is 20 to 104 months. The patients of odonto HPP only showed premature loss of deciduous anterior tooth, while the patients with childhood HPP also showed premature loss of multiple deciduous molars. Panoramic radiographic film revealed enlarged pulp chambers and radicular canals in some primary and permanent teeth. The enamel hypoplasia, hypoplastic short roots, and alveolar resorption of deciduous molar were observed in some cases. The serum alkaline phosphatase (ALP) (30-107 U/L) levels of all the patients were lower than that in the normal children of same age and gender, and the ALP value of the 1-3 years old girls with childhood HPP (30-33 U/L) was lower than that of the three children with odonto HPP (61-107 U/L), but there was no significant difference in statistical analysis. There were 8 variation sites of ALP liver/bone/kidney (ALPL) gene detected in 5 children and their families, all of which were missense variation, including the new variants in the mutations of c.1334C>G(p.Ser445Cys) and c.1259G>T(p.Gly420Val) that were not reported in the literature. One case was autosomal dominant inheritance and other 4 cases were complex heterozygous variation with autosomal recessive inheritance. Conclusions: Pediatric stomatologists are often the first doctors to detect childhood and odonto HPP. Diagnosis of mild HPP is often delayed. The severity of HPP is related to serum ALP level and ALPL gene mutation sites.

4.
Proc Natl Acad Sci U S A ; 120(12): e2300481120, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36913585

RESUMO

Graphite is one of the most chemically inert materials. Its elementary constituent, monolayer graphene, is generally expected to inherit most of the parent material's properties including chemical inertness. Here, we show that, unlike graphite, defect-free monolayer graphene exhibits a strong activity with respect to splitting molecular hydrogen, which is comparable to that of metallic and other known catalysts for this reaction. We attribute the unexpected catalytic activity to surface corrugations (nanoscale ripples), a conclusion supported by theory. Nanoripples are likely to play a role in other chemical reactions involving graphene and, because nanorippling is inherent to atomically thin crystals, can be important for two-dimensional (2D) materials in general.

5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(11): 1080-1086, 2022 Nov 24.
Artigo em Chinês | MEDLINE | ID: mdl-36418276

RESUMO

Objective: This study sought to investigate the impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease. Methods: We retrospectively analyzed clinical data of male patients diagnosed with suspected coronary microvascular dysfunction (CMD) in the First Hospital of Shanxi Medical University between December 2015 and August 2021. All patients underwent the one-day rest and stress 13N-ammonia positron emission tomography myocardial perfusion imaging. Overall obesity was defined by body mass index (BMI) ≥28 kg/m2 and abdominal obesity was defined by waist circumference ≥90 cm. Hyperemic myocardial blood flow (MBF)<2.3 ml·min-1·g-1 or coronary flow reserve (CFR)<2.5 were referred as CMD. All patients were grouped based on their BMI and waist circumference. MBF, CFR, the incidence of CMD, hemodynamic parameters, and cardiac function were compared among the groups. Results: A total of 136 patients were included. According to BMI and waist circumference, patients were categorized into 3 groups: control group (n=45), simple abdominal obesity group (n=53) and compound obesity group (n=38). Resting MBF did not differ between groups (F=0.02,P=0.994). Compared with the control group, hyperemic MBF was significantly lower in the simple abdominal obesity and compound obesity groups ((2.82±0.64) ml·min-1·g-1, (2.44±0.85) ml·min-1·g-1 and (2.49±0.71) ml·min-1·g-1, both P<0.05, respectively). Hyperemic MBF was comparable among the groups of patients with obesity (P=0.772). CFR was significantly lower in the simle abdominal obesity group compared with the control group (2.87±0.99 vs. 3.32±0.62,P=0.012). Compared with the control group, CFR tended to be lower in the compound obesity group (3.02±0.91 vs. 3.32±0.62,P=0.117). The incidence of CMD was significantly higher in both the simple abdominal obesity and compound obesity groups than in the control group (62.3%, 52.6% vs. 22.2%, both P<0.01, respectively). Waist circumference was an independent risk factor for male CMD (OR=1.057, 95%CI: 1.013-1.103, P=0.011). Conclusions: In male patients with non-obstructive coronary artery disease, abdominal obesity is associated with decreased coronary microvascular function. Male patients with simple abdominal obesity face the highest risk of CMD.


Assuntos
Doença da Artéria Coronariana , Hiperemia , Humanos , Masculino , Circulação Coronária/fisiologia , Obesidade Abdominal , Estudos Retrospectivos , Obesidade/epidemiologia
6.
J Electron Mater ; 51(7): 3843-3850, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497373

RESUMO

To realize the resource utilization of waste mask fibers (MF), a layer of ZnS nanoparticles was grown on MF by a one-step hydrothermal method, and a MF/ZnS sensor was successfully prepared. This is the first time that resource utilization of MF has been combined with the development of a high-performance gas sensor. The MF/ZnS sensor showed high sensitivity and recoverability to target vapors at room temperature. Compared with ZnS powder loaded on a ceramic substrate, the MF/ZnS composite responses to four analytes have been improved by 8.4~35.2 times. In addition, the time for the MF/ZnS sensor to complete one response-recovery cycle for all four analytes was less than 30 s. This should be attributed to the high gas permeability of the MF substrate, which made the ZnS particles loaded on the MF more fully exposed to contact with the target vapors. This work not only provides a simple and low-cost method to optimize the sensing performance of gas sensors but also provides a new way for the resource utilization of MF. Supplementary Information: The online version contains supplementary material available at 10.1007/s11664-022-09644-1.

9.
Zhonghua Zhong Liu Za Zhi ; 42(8): 665-669, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867459

RESUMO

Objective: To investigate the CT features and dynamic changes of new developed lung cancer in patients with connective tissue disease-related interstitial lung disease (CTD-ILD). Methods: A series of chest CT images of 58 CTD-ILD patients during follow-up were collected. The CT features of interstitial lung disease, the initial appearance time of lung cancer, the time of diagnosis of lung cancer, the morphological characteristics (location, shape, size) of lung cancer lesions and the dynamic changes of CT features were analyzed. Results: Among 58 patients, rheumatoid arthritis was the most common (31 cases). Chest CT images showed coexistence of two or more interstitial CT signs. During the follow-up, a total of 59 lung cancer lesions were found. The median time of lung cancer lesion occurred was 289 days. The median delay in diagnosis was 43 days. There were 44 cases of non-small cell lung cancer (including 23 cases of squamous cell carcinoma and 19 cases of adenocarcinoma), 12 cases of small cell lung cancer. Forty-three (72.9%) lesions were located in the lower lobes and 41 (69.5%) lesions were located in the area of pulmonary interstitial fibrosis. According to CT morphological characteristics of lung cancer, nodular type (37 cases), inflammatory consolidation (12 cases) and intra-honeycomb type (10 cases) were identified. Conclusions: The chest CT features of patients with CTD-ILD are complex. New developed lung cancer is easily missed or misdiagnosed in the early stage. Pay attention to the special CT characteristics of CTD-ILD with lung cancer is helpful for early diagnosis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Doenças do Tecido Conjuntivo/complicações , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Neoplasias Pulmonares/complicações , Tomografia Computadorizada por Raios X/métodos , Doenças do Tecido Conjuntivo/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem
11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(3): 205-210, 2020 Mar 24.
Artigo em Chinês | MEDLINE | ID: mdl-32234177

RESUMO

Objective: To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries. Methods: We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF<2.17 ml·min(-1)·g(-1). Results: Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ(2)=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ(2)=0.915, P=0.339). RMBF ((0.83±0.14) ml·min(-1)·g(-1) vs. (0.82±0.17) ml·min(-1)·g(-1)), SMBF ((2.13±0.60) ml·min(-1)·g(-1) vs. (1.91±0.50) ml·min(-1)·g(-1)) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions: CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Angiografia Coronária , Circulação Coronária , Estenose Coronária , Humanos , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos
12.
Sci Total Environ ; 648: 460-471, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121045

RESUMO

The combined and individual hydrological impacts of climate variation and urbanization have been extensively discussed over the past few decades, yet little is known about the relative impact of each. In this paper we took one of the most developed regions worldwide, Yangtze River Delta, as an example to analyse the long-term relative impacts of precipitation and urbanization change on water level alterations, based on precipitation, water level series, and annual impervious area data from 1960 to 2015. Abrupt changes detection in the water level series divided the data into the pre-impact period (1960-1988) and impacted period (1989-2015), and relative impacts of precipitation and urbanization on the water level increase from pre-impacted to impacted period, as well as their spatial and seasonal variations were estimated with the elasticity method. The results indicated that the urbanization change showed no distinct influence on the water level rise in the pre-impact period, while the precipitation played distinct roles only during summer months in the impacted period; the precipitation dominated two thirds of the water level rise in flood season, and in non-flood season the urbanization controlled the two thirds of the water level rise; spatially, the water level variations in old and new urban area were dominated by precipitation and urbanization process respectively; compared with precipitation amount, the water level correlated more strongly to the contribution ratio of precipitation. The results would provide a good reference for flood control and water resource management in the river basin, especially in the economically developed areas.

13.
Zhonghua Zhong Liu Za Zhi ; 40(11): 847-850, 2018 Nov 23.
Artigo em Chinês | MEDLINE | ID: mdl-30481937

RESUMO

Objective: To investigate the value of computed tomography (CT) texture analysis in differential diagnosis of inflammatory and malignant pulmonary nodules. Methods: The image data of 54 patients with lung cancer and 36 patients with pulmonary inflammatory nodules were retrospectively collected in our hospital. All the patients received chest CT scan. CT texture analysis of entropy, correlation degree and contrast ratio were performed by the MaZda software. The receiver operating characteristic curve (ROC) was established and the area under the curve (AUC) was calculated to evaluate the value of CT texture analysis in differential diagnosis of inflammatory and malignant pulmonary nodules. Results: In the lung cancer group, the value of entropy, correlation degree and contrast ratio were 1.58±0.07, 0.02±0.17 and 8.79±2.59, respectively. In the inflammatory nodules group, the value of entropy, correlation degree and contrast ratio were 1.51±0.04, 0.22±0.16 and 12.53±2.24, respectively. The differences were all statistically significant (P values were 0.008, 0.027, and 0.006, respectively) between two groups. There was not statistically significant difference (P>0.05) in the CT values between the lung cancer group and the inflammatory nodule group based on the non-contrast enhanced CT scan. Meanwhile, there was no statistically significant difference (P>0.05) in the value of entropy, correlation degree or contrast ratio between two groups based on arterial phase or venous phase of contrast enhanced CT. The ROC analysis showed that the AUC in differentiating the lung cancer and inflammatory nodules was 0.821, 0.778 and 0.875, respectively. The AUC of combination of three phases was 0.931, which was higher than the AUC of entropy, correlation degree and contrast ratio respectively (P<0.01). The sensitivity was 88.9%, and the specificity was 87.5%. Conclusion: CT texture analysis is a high-potential image analysis method, which can provide more information for the differential diagnosis of benign and malignant pulmonary nodules.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Área Sob a Curva , Diagnóstico Diferencial , Entropia , Humanos , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Zhonghua Zhong Liu Za Zhi ; 40(8): 610-613, 2018 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-30139032

RESUMO

Objective: To investigate the influential factors of efficacy of the first (131)I ablation therapy for thyroid remnant in papillary thyroid microcarcinoma (PTMC) patients after thyroidectomy. Methods: Eighty-nine PTMC patients who underwent twice (131)I ablation therapy and (131)I whole body follow-up scan ((131)I-WBS) within 5 to 8 months in our department from September 2007 to October 2016 were identified and enrolled in present study. Patients were divided into complete-ablation group and uncomplete-ablation group according to whether or not radioactivity was detected at the thyroid bed in (131)I-WBS. The χ(2) test and multi-variance Binary logistic regression were performed for the factors which might affect the therapeutic efficacy. Results: The first (131)I ablation therapy was successful in 41 of 89 patients (46.07%). Residual thyroid weight was found to be associated with therapeutic efficacy (P<0.05), while gender, age, surgical method, lesions'maximum diameter, with or without LN metastasis, with or without distant metastasis, time of operation from first (131)I treatment, lesions'number, thyroid stimulating hormone (TSH), thyroglobulin (Tg), the consistency of (131)I-WBS and (99)Tc(m)-pertechnatate, TNM stage, ATA risk, Tg/TSH ratio were not significant associated with therapeutic efficacy. Binary logistic regression analysis was performed in these respects and it indicated that residual thyroid weight and ATA risk were not statistically significant independent variable (P>0.05). Conclusions: Residual thyroid weight might affect efficacy of the first (131)I ablation therapy on thyroid remnant in PTMC patients after thyroidectomy, but it is not an independent factor. Multiple interrelated factors should be considered when predicting the efficacy of the first (131)I ablation therapy.


Assuntos
Carcinoma Papilar/radioterapia , Carcinoma Papilar/cirurgia , Radioisótopos do Iodo/uso terapêutico , Glândula Tireoide/efeitos da radiação , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Fatores Etários , Carcinoma Papilar/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Neoplasia Residual , Tamanho do Órgão , Fatores Sexuais , Tireoglobulina/análise , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Tireotropina/análise , Resultado do Tratamento
16.
Lett Appl Microbiol ; 66(5): 447-454, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29488630

RESUMO

Fresh-cut produce is at greater risk of Salmonella contamination. Detection and early warning systems play an important role in reducing the dissemination of contaminated products. One-step Reverse Transcription Polymerase Chain Reaction (RT-qPCR) targeting Salmonella tmRNA with or without a 6-h enrichment was evaluated for the detection of Salmonella in fresh-cut vegetables after 6-h storage. LOD of one-step RT-qPCR was 1·0 CFU per ml (about 100 copies tmRNA per ml) by assessed 10-fold serially diluted RNA from 106 CFU per ml bacteria culture. Then, one-step RT-qPCR assay was applied to detect viable Salmonella cells in 14 fresh-cut vegetables after 6-h storage. Without enrichment, this assay could detect 10 CFU per g for fresh-cut lettuce, cilantro, spinach, cabbage, Chinese cabbage and bell pepper, and 102 CFU per g for other vegetables. With a 6-h enrichment, this assay could detect 10 CFU per g for all fresh-cut vegetables used in this study. Moreover, this assay was able to discriminate viable cells from dead cells. This rapid detection assay may provide potential processing control and early warning method in fresh-cut vegetable processing to strengthen food safety assurance. SIGNIFICANCE AND IMPACT OF THE STUDY: Significance and Impact of the Study: Fresh-cut produce is at greater risk of Salmonella contamination. Rapid detection methods play an important role in reducing the dissemination of contaminated products. One-step RT-qPCR assay used in this study could detect 10 CFU per g Salmonella for 14 fresh-cut vegetables with a 6-h short enrichment. Moreover, this assay was able to discriminate viable cells from dead cells. This rapid detection assay may provide potential processing control and early warning method in fresh-cut vegetable processing to strengthen food safety assurance.


Assuntos
Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Salmonella enterica/isolamento & purificação , Verduras/microbiologia , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Gastroenterite/microbiologia , Gastroenterite/prevenção & controle , RNA Bacteriano , Infecções por Salmonella/microbiologia , Infecções por Salmonella/prevenção & controle , Salmonella enterica/genética
18.
Zhonghua Zhong Liu Za Zhi ; 39(10): 759-763, 2017 Oct 23.
Artigo em Chinês | MEDLINE | ID: mdl-29061020

RESUMO

Objective: To explore the diagnostic efficacy of by (18)F-FDG PET-CT for hypermetabolic thyroid nodules. Methods: To retrospectively analyze the clinical data of 3 192 patients underwent (18)F-FDG PET-CT in our hospital from May 2012 to October 2014. Among them, 98 patients were diagnosed with focal hypermetabolic thyroid nodules. 61 of the 98 patients were diagnosed with malignant or benign thyroid nodules using histopathological or clinical follow-up (22 malignant nodules, 39 benign nodules). The average age of these 61 patients was 61.6±12.5 years. Results: The lgSUVmax of malignant group (0.69±0.31) was significantly higher than that in benign group (0.43±0.27) (P=0.001). There was no significant difference in age, gender, nodule size, minimum diameter of nodule, lgCT, calcification, the boundary definition, density uniformity, and history of malignancy between the two groups (P>0.05). Binary Logistic regression indicated the AUC of Logistic regressive model(AUC) was 0.866±0.049 (95% CI: 0.769-0.963), and the malignant AUCs of ROC curve was 0.747±0.068 (95%CI: 0.614-0.880) which was only determined by lgSUVmax. The difference was statistically significant (P<0.01). Conclusion: (18)F-FDG PET-CT imaging can not only detect hypermetabolic thyroid nodules, but also have a certain clinical value for the identification of benign and malignant nodules.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Fatores Etários , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Fatores Sexuais , Nódulo da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/patologia
19.
Plant Biol (Stuttg) ; 19(6): 851-858, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28787541

RESUMO

Metabolism of strigolactones (SLs) can improve the efficiency of nutrient use by regulating the development of roots and shoots in crops, making them an important research focus for molecular breeding. However, as a very important plant hormone, the molecular mechanism of SL signal transduction still remains largely unknown. In this study, we isolated an indica high-tillering dwarf mutant 4 (htd4), a spontaneous mutant of rice, from the restorer line Gui99. Mapping and sequencing analysis showed that htd4 was a novel allelic mutant of D14, in which a single base substitution forms a premature termination codon. Quantitative RT-PCR analyses revealed that expression levels of the genes D10, D17, D27, D3 and D14 increased significantly, while expression of D53 decreased in htd4, compared with the wild type. A subcellular localisation assay showed that the mutant of D14 in htd4 did not disturb the normal localisation of D14 proteins. However, a BiFC assay suggested that the mutant-type D14 could not interact with D3. Additionally, compared with other D14 allelic mutants, htd4 was the first mutant of D14 discovered in indica, and the differences in many yield traits such as plant height, seed-setting rate and grain sizes between htd4 and the wild type were less than those between other D14 allelic mutants and the wild type. Therefore, htd4 is considered a mild phenotype allelic mutant of D14. We conclude that the absence of functional D14 caused the high-tillering dwarf phenotype of htd4. Our results may provide vital information for research on D14 function and the application of htd4 in molecular breeding.


Assuntos
Mutação/genética , Oryza/genética , Alelos , Mapeamento Cromossômico , Códon/genética , Genes de Plantas/genética , Oryza/crescimento & desenvolvimento , Fenótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
20.
J Dent Res ; 95(13): 1452-1456, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27872324

RESUMO

The salivary glands and oral bacteria play an essential role in the conversion process from nitrate (NO3-) and nitrite (NO2-) to nitric oxide (NO) in the human body. NO is, at present, recognized as a multifarious messenger molecule with important vascular and metabolic functions. Besides the endogenous L-arginine pathway, which is catalyzed by complex NO synthases, nitrate in food contributes to the main extrinsic generation of NO through a series of sequential steps (NO3--NO2--NO pathway). Up to 25% of nitrate in circulation is actively taken up by the salivary glands, and as a result, its concentration in saliva can increase 10- to 20-fold. However, the mechanism has not been clearly illustrated until recently, when sialin was identified as an electrogenic 2NO3-/H+ transporter in the plasma membrane of salivary acinar cells. Subsequently, the oral bacterial species located at the posterior part of the tongue reduce nitrate to nitrite, as catalyzed by nitrate reductase enzymes. These bacteria use nitrate and nitrite as final electron acceptors in their respiration and meanwhile help the host to convert nitrate to NO as the first step. This review describes the role of salivary glands and oral bacteria in the metabolism of nitrate and in the maintenance of NO homeostasis. The potential therapeutic applications of oral inorganic nitrate and nitrite are also discussed.


Assuntos
Bactérias/metabolismo , Boca/microbiologia , Óxido Nítrico/metabolismo , Saliva/fisiologia , Glândulas Salivares/metabolismo , Arginina/metabolismo , Alimentos , Homeostase , Humanos , Nitrato Redutase/metabolismo , Nitratos/metabolismo , Nitritos/metabolismo , Oxirredução , Saliva/microbiologia
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