Objective:To study the movement regularity of Ca~(2+) in tooth hard tissue.Methods:14 extracted intact caries-free teeth were cleaned and then immersed into artificial saliva in a divice with 3 chambers for enamel part,dentin part and cement part respectively.The concentration of Ca~(2+) in the chambers was measured with an ion meter,TECHNICON(AXON,USA),24 h after immersion of each tooth.Results:The Ca~(2+) concentration in tooth immersed fluid of enamel part was higher than that of dentin part(P

0.05). Conclusion: There is surface potential in teeth and the potent ial can be affected by the electrolyte surroundings.

Digital PCR is an emerging analysis technology for absolute quantification after realtime-PCR. Through digital PCR, single DNA molecules are distributed into isolated reactions, and the product with fluorescence signal can be detected and analyzed after amplification. With the advantages of higher sensitivity and accuracy, digital PCR, independent of a standard curve, is developing rapidly and applied widely to the next generation sequencing and detection fields, such as gene mutation, copy number variation, microorganism, and genetically modified food. In this article, we reviewed the quantitative method and research progress of digital PCR technology in the main application fields.

We evaluated an astaxanthin overproducing Phaffia rhodozyma JMU-MVP14, and developed astaxanthin high-yielding fermentation process. We analyzed several fermentation parameters, i.e., biomass, astaxanthin and total carotenoids content to compare the characteristics of P rhodozyma JMU-MVP14 and the original strain through flask fermentation experiments. We conducted batch and fed-batch fermentation experiments in 7 L fermentor to investigate the effects of pH controlling models and feeding medium compositions on the production of astaxanthin. We further evaluated the capability and practical value of P rhodozyma JMU-MVP14 by fed-batch cultivation in the 1 m3 fermentor. Flask fermentation experiments revealed that P. rhodozyma JMU-MVP14 produced high yield of astaxanthin and carotenoids with specific productivity of astaxanthin and specific productivity of total carotenoids of 6.01 mg/g and 10.38 mg/g. Results of batch culture experiments in the 7 L fermentor showed that controlling the pH by ammonia auto-feeding was better than discontinuously adjusting pH value at 6.0 with regard to the high productivities of biomasses and astaxanthin. This P. rhodozyma strain synthesized astaxanthin partially linked to the growth with the Ks and pmax of 0.20 h ' and 21.73 g/L, respectively. Results of batch-fed fermentations in 7 L fermentor indicated that the complex feeding medium consisted of 50% glucose, 0.5% yeast extract and 0.3% corn steep syrup had lower astaxanthin productivity than the simple feeding medium containing only 50% glucose, which produced biomass, volumetric productivity of astaxanthin, volumetric productivity of total carotenoids, specific productivity of astaxanthin and total carotenoids at 32.81 g/L, 155.99 mg/L, 4.94 mg/g, 399.99 mg/L and 12.19 mg/g, respectively. As fed-batch cultured in 1 m3 fermentor, P rhodozyma JMU-MVP14 yielded 85.11 g/L of biomass, 279.96 mg/L of volumetric productivity of astaxanthin, 618.01 mg/L of volumetric productivity of total carotenoids, 3.29 mg/g of specific productivity of astaxanthin and 7.26 mg/g of specific productivity of total carotenoids. Additionally, P rhodozyma JMU-MVP14 cell contained 21.54% of protein, 41.34% of carbohydrate and 34.31% of lipid. These comprehensive results suggest that P. rhodozyma JMU-MVPl14 has great practical prosperity related to its strong ability to produce astaxanthin and good value byproducts.
Basidiomycota ; genetics ; growth & development ; metabolism ; Batch Cell Culture Techniques ; Carotenoids ; biosynthesis ; Culture Media ; Fermentation ; Hydrogen-Ion Concentration ; Industrial Microbiology ; Kinetics ; Xanthophylls ; biosynthesis

Phaffia rhodozyma is one of the organisms for production of astaxanthin, and the key process for extracting intracellular astaxanthin is cell disruption. In this work, cell disruption for extracting astaxanthin from Phaffia rhodozyma was studied with autoclave method at low acid concentration. The optimum disrupting conditions were: autoclave pressure 0.1 MPa, 121 degrees C; hydrochloric acid concentration 0.5 mol/L; liquid to material ratio (V/W) 30 mL/g dry cell weight and disruption time 2 min. Under the optimum conditions, medium scale experiment showed that astaxanthin and total carotenoids recovery from Phaffia rhodozyma were (84.8 +/- 3.2)% and (93.3 +/- 2)%, respectively. This new method can lead to no poisonous residues and get high extraction yield, which have good prospects to be put into industrial production.
Basidiomycota ; chemistry ; Carotenoids ; isolation & purification ; Cell Wall ; metabolism ; Hot Temperature ; Hydrochloric Acid ; Xanthophylls ; isolation & purification

An oral synechia is a fibrous or soft tissue adhesion between the maxilla and the mandible. These synechiae can appear at various locations in the oral cavity, with alveolar synechia being one of the manifestations. Alveolar synechia is a rare congenital deformity and often accompanied by additional congenital defects, such as cleft lip or palate, microglossia, micrognathia, or TMJ anomalies. Among these, cleft palate is the most common. A case of congenital alveolar synechiae with cleft palate is reported. The child is in good condition after surgical treatment. The etiology and treatment are discussed.

Regional odontodysplasia(ROD)is a localized developmental anomaly involving deciduous and perma-nent dentition,with a significant impact on patients.The affected teeth display unique ghost-like radiological characteris-tics,clinically manifesting as delayed tooth eruption,abnormal tooth morphology,and recurrent swelling of gingiva.In this paper,we report a case of a 2-year-old patient with ROD whose chief complaint was facial cellulitis.We analyze the medical history,clinical examination,radiographic findings,and histologic findings,and review the pathological fea-tures,pathogenesis,multidisciplinary diagnosis,and treatment of ROD.This rare case,which offers clinical samples for its further study,can provide a deeper study of ROD.

Hypophosphatemia rickets is a rare disease that is divided into two categories,namely,hereditary and ac-quirability.Its clinical manifestations include growth disorders,limb deformities and dysfunction,poor mineralization of the teeth,and growth retardation in children as well as hyperparathyroidism,osteoarthritis,osteomalacia,and pseudofrac-ture in adults.Oral manifestations include non-carious teeth with recurrent apical periodontitis,periapical abscess and even cellulitis,periodontitis,and early tooth loss.X-linked hypophosphatemia rickets(XLHR)accounts for approximate-ly 80％of all hypophosphatemia rickets.We report a 3-year-old child with XLHR whose first diagnosis was apical peri-odontitis of multiple non-carious and non-traumatic teeth.Through medical history,clinical examination,laboratory ex-amination,radiographic findings,genotype testing,and literature analysis,we analyze the pathogenesis,clinical manifes-tations,radiographic features,diagnosis and differential diagnosis,treatment,and follow-up.This work provides refer-ence for clinical diagnosis and treatment and reduces missed diagnosis and misdiagnosis by dentists.

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 The 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 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 was 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.

OBJECTIVESince 1986, the reference of birth weight for gestational age has not been updated. The aim of this study was to set up Chinese neonatal network to investigate the current situation of birth weight in China, especially preterm birth weight, to develop the new reference for birth weight for gestational age and birth weight curve.

METHODA nationwide neonatology network was established in China. This survey was carried out in 63 hospitals of 23 provinces, municipalities and autonomous regions. We continuously collected the information of live births in participating hospitals during the study period of 2011-2014. Data describing birth weight and gestational age were collected prospectively. Newborn's birth weight was measured by electronic scale within 2 hours after birth when baby was undressed. The evaluation of gestational age was based on the combination of mother's last menstrual period, ultrasound in first trimester and gestational age estimation by gestational age scoring system.

STATISTICAL ANALYSISthe growth curve was drawn by using LMSP method, which was conducted in GAMLSS 1.9-4 software package in R software 2.11.1.

RESULTA total of 159 334 newborn infants were enrolled in this study. There were 84 447 male and 74 907 female. The mean birth weight was (3 232 ± 555) g, the mean birth weight of male newborn was (3 271 ± 576) g, the mean weight of female newborn was (3 188 ± 528) g. The test of the variables' distribution suggested that the distribution of gestational age and birth weight did not fit the normal distribution, the optimal distribution for them was BCT distribution. The Q-Q plot test and worm plot test suggested that this curve fitted the distribution optimally. The male and female neonatal birth weight curve was developed using the same method.

CONCLUSIONUsing GAMLSS method to establish nationwide neonatal birth weight curve, and the first time to update the birth weight reference in recent 28 years.