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1.
Eur Radiol ; 34(1): 16-25, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37526667

ABSTRACT

OBJECTIVES: To predict the probability of occult lymph node metastasis (OLNM) in the central cervical by analyzing the dual-energy computed tomography (DECT) parameters derived from papillary thyroid carcinoma (PTC). METHODS: Data were retrospectively collected from patients with pathologically confirmed PTC who underwent arterial and venous phases of enhanced DECT with concurrent central neck lymph node dissection (CLND). Three clinical features, three shape-related features, and twenty-six DECT-derived parameters were measured. The univariate and multivariate analyses were applied to select the relevant parameters and develop the nomogram. RESULTS: A total 140 cases with negative diagnosis of cervical central lymph node metastases by preoperative evaluation were included, among which 88 patients with metastasis (OLNM +) and 52 patients without metastasis (OLNM -) were finally confirmed by pathology. (1) Anteroposterior/transverse diameter ratio (A/T) derived from the PTC focus had significant difference between the OLNM + and OLNM - groups (p < 0.05). (2) In the arterial phase, iodine concentration (ICarterial), normalized iodine concentration (NICarterial), effective atomic number (Zeff-arterial), electron density (EDarterial), and slope of energy curve (karterial) from PTC focus showed significant difference (all p < 0.05) between the two groups. In the venous phase, only the CT value under the 40 keV (HU40keVvenous) had differences (p < 0.05). (3) The nomogram was produced to predict the probability of OLNM, and the AUC, sensitivity, and specificity in the training and test cohort were 0.830, 75.0%, 76.9%, and 0.829, 65.9%, 84.6%, respectively. CONCLUSIONS: DECT parameters combined with shape-related feature derived from PTC might be used as predictors of OLNM in the central neck. CLINICAL RELEVANCE STATEMENT: Preoperative imaging evaluation combining shape-related features and dual-energy CT parameters could serve as a reference to discern occult lymph node metastasis in central neck during the surgically planning of papillary thyroid carcinoma. KEY POINTS: • Papillary thyroid carcinoma (PTC) patients may have occult lymph node metastasis (OLNM) in the central neck, which is extremely difficult to find by preoperative imaging examination. • Dual-energy CT quantitative evaluation has higher accuracy than conventional CT and can predicting OLNM in the central neck of PTC. • Dual-energy CT quantitative parameters and morphology of PTC can serve as a useful tool in predicting OLNM in the central neck, and as a guide for personalized treatment.


Subject(s)
Carcinoma, Papillary , Iodine , Thyroid Neoplasms , Humans , Thyroid Cancer, Papillary/diagnostic imaging , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/pathology , Lymphatic Metastasis/diagnostic imaging , Lymphatic Metastasis/pathology , Retrospective Studies , Carcinoma, Papillary/diagnostic imaging , Carcinoma, Papillary/pathology , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Tomography, X-Ray Computed , Neck/pathology
2.
Soft Matter ; 20(22): 4422-4433, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38775112

ABSTRACT

Biogenic purine crystals can function in vision as light scatters, mirrors, and multilayer reflectors and produce structural colors or depolarization for camouflage. Xanthine crystals form irregular multifocal mirrors in the median ocellus of Archaeognatha. It is important to broaden the study of crystallization strategies to obtain organic crystals with purine rings in the laboratory. In this work, a facile one-step synthesis route to fabricate bio-inspired xanthine crystals is reported for the first time. The obtained rhomboidal xanthine nanoplates have similar morphology and size to biogenic xanthine crystals. Their length and thickness are about 2-4 µm and 50 nm, respectively. Lattice parameters, crystal structure, formation mechanism and optical properties of synthetic single-crystalline xanthine nanoplates were investigated in detail in this work. The obtained xanthine nanoplate crystals are proposed to be anhydrous xanthine with monoclinic symmetry, and the xanthine nanoplates mainly expose the (100) plane. It is proposed that the anhydrous xanthine nanoplates are formed via an amorphous xanthine intermediate precursor. The synthetic anhydrous xanthine nanoplates exhibit excellent optical properties, including high diffuse reflectivity, strong depolarization and pearlescent luster. This work provides a new design to synthesize bio-inspired organic molecular crystals with excellent optical properties.

3.
Biochem Biophys Res Commun ; 671: 80-86, 2023 09 03.
Article in English | MEDLINE | ID: mdl-37300944

ABSTRACT

2-(2-Phenylethyl)chromones (PECs) are the main bioactive components of agarwood which showed diverse pharmaceutical activities. Glycosylation is a useful structural modification method to improve compounds' druggability. However, PEC glycosides were rarely reported in nature which largely limited their further medicinal investigations and applications. In this study, the enzymatic glycosylation of four naturally separated PECs 1-4 was achieved using a promiscuous glycosyltransferase UGT71BD1 identified from Cistanche tubulosa. It could accept UDP-Glucose, UDP-N-acetylglucosamine and UDP-xylose as sugar donors and conduct the corresponding O-glycosylation of 1-4 with high conversion efficiencies. Three O-glucosylated products 1a (5-hydroxy-2-(2-phenylethyl)chromone 8-O-ß-D-glucopyranoside), 2a (8-chloro-2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) and 3a (2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) were prepared and structurally elucidated as novel PEC glucosides based on NMR spectroscopic analyses. Subsequent pharmaceutical evaluation found that 1a showed remarkably improved cytotoxicity against HL-60 cells, whose cell inhibition rate was 19 times higher than that of its aglycon 1. The IC50 value of 1a was further determined to be 13.96 ± 1.10 µM, implying its potential as a promising antitumor-leading candidate. To improve the production of 1, docking, simulation and site-directed mutagenesis were performed. The important role of P15 in the glucosylation of PECs was discovered. Besides, a mutant K288A with a two-fold increased yield for 1a production was also afforded. This research reported the enzymatic glycosylation of PECs for the first time, and also provide an eco-friendly pathway for the alternative production of PEC glycosides for leading compounds discovery.


Subject(s)
Chromones , Glycosides , Humans , Chromones/pharmacology , Glycosyltransferases/genetics , Glycosyltransferases/metabolism , Pharmaceutical Preparations , Catalysis , Uridine Diphosphate , Molecular Structure
4.
Zhongguo Zhong Yao Za Zhi ; 48(2): 336-348, 2023 Jan.
Article in Zh | MEDLINE | ID: mdl-36725223

ABSTRACT

As a biocatalyst, enzyme has the advantages of high catalytic efficiency, strong reaction selectivity, specific target products, mild reaction conditions, and environmental friendliness, and serves as an important tool for the synthesis of complex organic molecules. With the continuous development of gene sequencing technology, molecular biology, genetic manipulation, and other technologies, the diversity of enzymes increases steadily and the reactions that can be catalyzed are also gradually diversified. In the process of enzyme-catalyzed synthesis, the majority of common enzymatic reactions can be achieved by single enzyme catalysis, while many complex reactions often require the participation of two or more enzymes. Therefore, the combination of multiple enzymes together to construct the multi-enzyme cascade reactions has become a research hotspot in the field of biochemistry. Nowadays, the biosynthetic pathways of more natural products with complex structures have been clarified, and secondary metabolic enzymes with novel catalytic activities have been identified, discovered, and combined in enzymatic synthesis of natural/unnatural molecules with diverse structures. This study summarized a series of examples of multi-enzyme-catalyzed cascades and highlighted the application of cascade catalysis methods in the synthesis of carbohydrates, nucleosides, flavonoids, terpenes, alkaloids, and chiral molecules. Furthermore, the existing problems and solutions of multi-enzyme-catalyzed cascade method were discussed, and the future development direction was prospected.


Subject(s)
Alkaloids , Biological Products , Biological Products/chemistry , Catalysis , Biocatalysis
5.
J Nat Prod ; 85(7): 1826-1836, 2022 07 22.
Article in English | MEDLINE | ID: mdl-35791759

ABSTRACT

Multiple-glycosylated glycosides are a major source of bioactive leads. However, most of the currently reported glycosyltransferases (GTases) mainly catalyze glycosylation of aglycones without sugar group substitution. GTases accepting diverse glycosides as substrates are rarely reported. In this article, a new GTase UGT71BD1 was identified from Cistanche tubulosa, a desert herb plant abundant with various phenylethanoid glycosides (PhGs). Interestingly, UGT71BD1 showed no activity toward the aglycone of PhGs. Instead, it could catalyze the further glycosylation of PhG compounds to produce new phenylethanoid multiglycosylated glycosides, including the natural rarely separated tetraglycoside PhGs. Extensive assays found the unprecedented substrate promiscuity of UGT71BD1 toward diverse glycosides including flavonoid glycosides, stilbene glycosides, and coumarin glycosides, performing further mono- or diglycosylation with efficient conversion rates. Using UGT71BD1, six multiglycosylated glycosides were prepared and structurally identified by NMR spectroscopy. These products showed enhanced pharmacological activities compared with the substrates. Docking, dynamic simulation, and mutagenesis studies identified key residues for UGT71BD1's activity and revealed that the sugar modules in glycosides play crucial roles in substrate recognition, thus partly illuminating the unusual substrate preference of UGT71BD1 toward diverse glycosides. UGT71BD1 could be a potential enzyme tool for glycosylation of diverse glycosides.


Subject(s)
Cistanche , Cistanche/chemistry , Cistanche/metabolism , Glycosides/chemistry , Glycosylation , Glycosyltransferases/metabolism , Sugars
6.
BMC Ophthalmol ; 21(1): 299, 2021 Aug 14.
Article in English | MEDLINE | ID: mdl-34391397

ABSTRACT

BACKGROUND: To evaluate the prevalence of myopia in school students in Urumqi, China, and explore the influence of the interaction between parental myopia and poor reading and writing habits on myopia to identify the at-risk population and provide evidence to help school students avoid developing myopia. METHODS: A cross-sectional survey was conducted with 6,883 school students aged 7-20 years in Urumqi in December 2019. The Standard Eye Chart and mydriatic optometry were used to determine whether students had myopia. Falconer's method was used to calculate the heritability of parental myopia. Multivariate unconditional logistic regression models were used to analyze the risk factors for myopia and the additive and multiplicative interaction of parental myopia and poor reading and writing habits. RESULTS: After standardizing the age of the 6,883 students, the overall prevalence rate of myopia was 47.50 %. The heritability of parental myopia was 66.57 % for boys, 67.82 % for girls, 65.02 % for the Han group, and 52.71 % for other ethnicities. There were additive interactions between parental myopia and poor reading and writing habits; among them, parental myopia and poor eye habits when reading and writing (the distance between the eyes and book is less than 30 cm when reading and writing, fingers block the sight of one eye while holding the pen, and leaning one's body when reading and writing; habit 1) increased the risk of myopia by 10.99 times (odds ratio [OR] = 10.99, 95 % confidence interval [CI] = 8.33-14.68), parental myopia and poor reading posture (reading while lying down, walking, or in the car; habit 2) increased the risk of myopia by 5.92 times (OR = 5.92, 95 % CI = 4.84-7.27). There was no multiplicative interaction between parental myopia and habit 1 or habit 2 (OR = 0.69, 95 % CI = 0.44-1.08; OR = 0.89, 95 % CI = 0.66-1.21, respectively). CONCLUSION: The prevalence of myopia among students in Urumqi, Xinjiang is relatively high. The risk of developing myopia is affected by parental myopia and poor reading and writing habits. In addition, parental myopia amplifies the harm caused by poor reading and writing habits, thereby increasing the risk of myopia. Students with parents who have myopia should be targeted during myopia prevention efforts.


Subject(s)
Myopia , Reading , China/epidemiology , Cross-Sectional Studies , Female , Habits , Humans , Male , Myopia/epidemiology , Parents , Posture , Prevalence , Risk Factors , Schools , Students , Surveys and Questionnaires , Writing
7.
Chemistry ; 25(13): 3219-3223, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30681744

ABSTRACT

The thermal stability and structural transformation mechanism are critical for the industrial applications of zeolites and the design of new framework types. Herein, a new zeolite PKU-26 has been hydrothermally synthesized under fluoride conditions using a tetraethylammonium (TEA+ ) cation as the structure-directing agent (SDA) and its framework contains partial Q3 T atoms [Q3 for T(-O-T)3 OH]. Upon calcination, PKU-26 processed a single-crystal to single-crystal transformation to another novel zeolite PKU-27 with the elimination of terminal -OH groups and enhanced thermal stability up to 650 °C, exhibiting the first Q3 →Q4 transformation [Q4 for T(-O-T)4 ] in 3D zeolite frameworks. The mechanism of the structural transformation, involving proton transfer, framework dehydration, and TO4 reconstruction, is proposed and supported by theoretical calculations.

8.
Inorg Chem ; 58(24): 16785-16791, 2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31800233

ABSTRACT

Sensitization with dyes is the most promising option to narrow the band gap and improve visible-light absorption of TiO2. As ideal structure and reaction models of TiO2, titanium oxo clusters (TOCs) with exact crystal structure are beneficial for further understanding the structure-property relationship of TiO2. Most reports mainly focus on the synthesis and properties of TOCs, but research on the band-gap tuning of TOCs at the large range of 3.7-2.0 eV by chromophore ligands (CLs) has been lacking. Herein, six new Ti6-core-based TOCs (Ti6-TOCs) were successfully synthesized by using CLs in a simple and general approach. Each Ti6-TOC structure contains two Ti3(µ3-O) units featuring a flat or pyramidal mode as building blocks. Five Ti6-core structure types were present among the six Ti6-TOCs, which enriched the family of hexanuclear TOCs. To be noted, the band-gap values were tuned at a wide range of 3.41-1.98 eV by controlling the type and number of the CLs 2-hydroxypyridine, salicylaldoxime, and catechol in the structure. Density functional theory calculation revealed that the lowest-energy bands of these Ti6-TOCs are attributed to the CL-to-TiO core charge-transfer bands. This work provides a precise and wide-ranged band-gap tuning method for TOCs. Additionally, the six Ti6-TOCs exhibit good photocurrent response.

9.
Biochem Biophys Res Commun ; 495(4): 2396-2403, 2018 01 22.
Article in English | MEDLINE | ID: mdl-29278701

ABSTRACT

Pulmonary fibrosis (PF) is a chronic and ultimately fatal interstitial lung disease of various causes. The advent of nintedanib and pirfenidone provides treatment options for PF patients for the first time. However, the adverse effects of the two drugs such as gastrointestinal disorders and hepatic dysfunction often lead to treatment discontinuation. Gentiopicroside (GPS) is a natural secoiridoid glycoside from gentian species of medicinal plants, and has a variety of pharmacological activities, including hepatoprotective and cholagogic, anti-inflammatory, antinociceptive, and smooth muscle relaxing activities. The present study aimed to investigate the therapeutical effects of GPS on bleomycin (BLM)-induced PF in mice. Severe lung inflammation and fibrosis were observed in BLM-treated mice. GPS significantly ameliorated inflammatory and fibrotic responses in lungs of PF mice which were confirmed by histopathological examinations including light microscopy and transmission electron microscopy. Additionally, GPS significantly decreased the levels of inflammatory cytokines including TNF-α and IL-1ß in bronchoalveolar lavage fluid and reduced the content of hydroxyproline in lungs of PF mice. Furthermore, GPS significantly downregulated the expression of TGF-ß1 and CTGF in lungs of PF mice. In vitro, GPS inhibited epithelial-mesenchymal transition of A549 cells stimulated by TGF-ß1, in a dose-dependent manner. Our findings suggest that GPS has the potential as an ideal drug candidate for PF, as it has both anti-inflammatory and anti-fibrotic effects. Alveolar epithelial cells and TGF-ß1 may be the main target cells and molecule of GPS on BLM-induced PF, respectively.


Subject(s)
Iridoid Glucosides/administration & dosage , Lung/immunology , Pneumonia/immunology , Pneumonia/prevention & control , Pulmonary Fibrosis/immunology , Pulmonary Fibrosis/prevention & control , Animals , Anti-Inflammatory Agents/administration & dosage , Bleomycin , Cytokines/immunology , Dose-Response Relationship, Drug , Immunologic Factors/immunology , Lung/drug effects , Male , Mice , Pneumonia/chemically induced , Pulmonary Fibrosis/chemically induced , Treatment Outcome
10.
Soft Matter ; 13(3): 670-676, 2017 Jan 18.
Article in English | MEDLINE | ID: mdl-28009918

ABSTRACT

From catanionic fluoro-/hydro-carbon mixtures of fluoroacetic acid (CF3COOH) and tetradecyldimethylaminoxide (C14DMAO) in water, viscoelastic wormlike micelles are successfully constructed which are determined by cryo-TEM measurements. It is found that the formation and rheological behavior of the wormlike micelles are greatly affected by the total concentration and mixing ratio of CF3COOH and C14DMAO as well as temperature. The driving force for the formation of wormlike micelles here is considered to be the electrostatic attractive interaction between the two molecules which is confirmed by 1H NMR measurements. As far as we know, such wormlike micelles formed from the catanionic mixtures of fluorofatty acids and hydrocarbon surfactants have been rarely reported. Our work provides a simple method through mixing a perfluorofatty acid with a hydrocarbon surfactant to construct and understand the formation mechanism of catanionic fluoro-/hydro-carbon wormlike micelles, which should be a great advance in the fundamental research of wormlike micelles.

11.
Angew Chem Int Ed Engl ; 54(25): 7290-4, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25939492

ABSTRACT

One of the challenges in materials science has been to prepare crystalline inorganic compounds with mesopores. Although several design strategies have been developed to address the challenge, expansion of pore sizes in inorganic materials is more difficult compared to that for metal-organic frameworks. Herein, we designed a novel mesoporous germanate PKU-17 with 3D 48×16×16-ring channels by introducing two large building units (Ge10 and Ge7 clusters) into the same framework. The key for this design strategy is the selection of 2-propanolamine (MIPA), which serves as the terminal species to promote the crystallization of Ge7 clusters. Moreover, it is responsible for the coexistence of Ge10 and Ge7 clusters. To our knowledge, the discovery of PKU-17 sets a new record in pore sizes among germanates. It is also the first germanate that exhibits a good selectivity toward CO2 over N2 and CH4 .

12.
Chemistry ; 20(49): 16097-101, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25345719

ABSTRACT

A germanate zeolite, PKU-14, with a three- dimensional large-pore channel system was structurally characterized by a combination of high-resolution powder X-ray diffraction, rotation electron diffraction, NMR, and IR spectroscopy. Ordered Ge4 O4 vacancies inside the [4(6) .6(12) ] cages has been found in PKU-14, in which a unique (H2 O)2 dimer was located at the vacancies and played a structure-directing role. It is the first time that water clusters are found to be templates for ordered framework vacancies.

13.
Front Oncol ; 14: 1302196, 2024.
Article in English | MEDLINE | ID: mdl-38434689

ABSTRACT

Objective: The aim of this report was to comprehensively investigate the clinicopathological features, histological characteristics, and differential diagnosis of tall cell carcinoma with reversed polarity of the breast (TCCRP) to enhance the understanding of this tumour for precise therapeutic interventions. Methods: The clinicopathological characteristics and differential diagnosis of a patient with TCCRP were retrospectively analysed, and a systematic literature review was extracted from relevant published studies on PubMed. Results: All patients included in the study were female, with a median age of 51 years. Microscopically, the tumour cells exhibited a solid papillary growth pattern with tall columnar morphology and reversed nuclear polarity. Immunohistochemistry revealed that the tumours were triple-negative breast cancer (negative for ER, PR, and HER-2), with a low Ki-67 proliferation index. Different degrees of expression were observed for CK7, Calretinin, and S-100 markers; however, CK5/6 showed high expression levels. Conclusions: TCCRP is an uncommon invasive carcinoma subtype found in the breast. Its histological morphology resembles that of tall cell subtype papillary thyroid carcinoma. Accurate diagnosis requires the integration of histomorphological assessment along with immunohistochemistry and molecular genetics analysis.

14.
Front Oncol ; 14: 1346964, 2024.
Article in English | MEDLINE | ID: mdl-38482206

ABSTRACT

Pancreatoblastoma (PB) is a rare malignant pancreatic epithelial tumor that mostly occurs in children and occasionally occurs in adults. The tumor has acinar cell differentiation and squamous corpuscles/squamous epithelial islands, which are frequently separated by fibrous bundles. Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease characterized by the presence of numerous adenomatous polyps in the colon and rectum. Cases of pancreatoblastoma combined with familial adenomatous polyposis (FAP) are rarely reported. A review of a rare case of adult pancreatoblastoma with atypical histological morphology combined with familial adenomatous polyposis is presented herein. In this case, the patient was first diagnosed with familial adenomatous polyposis and subsequently found to have pancreatoblastoma 1 year and 3 months later. This suggests pancreatoblastoma may occur in patients with familial adenomatous polyposis or a family history of the condition, indicating a possible association between the two tumors. Therefore, pancreatoblastoma should be included in a differential diagnosis for FAP patients with a pancreatic mass. The final diagnosis of pancreatoblastoma depends on the pathological diagnosis. Acinar-like cells and squamous corpuscles/squamous epithelial cell islands under light microscopy are the key diagnostic points. This case report also can improve the awareness of clinicians, radiologists, and pathologists on the presence of rare tumor-adult pancreatoblastoma in patients with familial adenomatous polyposis.

15.
Acta Pharm Sin B ; 14(5): 2333-2348, 2024 May.
Article in English | MEDLINE | ID: mdl-38799633

ABSTRACT

Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides supply. However, the catalytic potential and structural basis of plant malonyltransferase are far from being fully elucidated. This work identified a new malonyltransferase CtMaT1 from Cistanche tubulosa. It displayed unprecedented mono- and/or di-malonylation activity toward diverse glucosides with different aglycons. A "one-pot" system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated glucosides. Structural investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse glucosides. Additionally, it recognizes malonyl-CoA through strong electrotactic and hydrogen interactions. QM/MM calculation revealed the H167-mediated SN2 reaction mechanism of CtMaT1, while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167, resulting in its high malonylation regiospecificity. Calculated energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates, emphasizing CtMaT1's preference for glucosides. Furthermore, a mutant CtMaT1H36A with notably increased di-malonylation activity was obtained. The underlying molecular mechanism was illuminated through MM/GBSA binding free energy calculation. This study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives, while also providing a versatile tool for enzymatic malonylation applications in pharmacology.

16.
Heliyon ; 10(12): e33438, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39027452

ABSTRACT

Background: Pediatric pneumonia presents a significant global health challenge, particularly in low- and middle-income countries. This study aimed to investigate the incidence of pneumonia in preschool children in Urumqi and its association with indoor environmental factors. Methods: This case-control study collected data from December 2018 to December 2019 on 1522 preschool children in Urumqi (779 boys and 743 girls) who were diagnosed with pneumonia by a physician. A control group of children who had never had pneumonia was matched in a 1:1 ratio based on gender, age, and ethnicity. Using questionnaires, data were collected on children's general characteristics, passive smoking, types of housing, flooring materials, and indoor dampness, analyzing potential factors associated with the incidence of pediatric pneumonia. Results: Multivariate analysis revealed that cesarean birth (odds ratio [OR] = 1.27; 95 % confidence interval [95%CI] = 1.08-1.48), being an only child (OR = 1.32; 95%CI = 1.13-1.55), antibiotic treatment during the first year of life (OR = 2.51; 95%CI = 1.98-3.19), passive smoking during the mother's pregnancy (OR = 1.62; 95%CI = 1.24-2.13), living in multi-family apartment housing (OR = 1.64; 95%CI = 1.28-2.10) and other types of housing (OR = 1.47; 95%CI = 1.09-1.99), laminate flooring (OR = 1.31; 95%CI = 1.01-1.72), and tile/stone/cement flooring flooring (OR = 1.31; 95%CI = 1.06-1.61), and dampness in dwelling (during first year of mother's pregnancy) (OR = 1.30; 95%CI = 1.04-1.63) were risk factors for pediatric pneumonia. The use of fresh air filtration systems in children's residences (OR = 0.66; 95%CI = 0.50-0.86) was identified as a protective factor. Conclusion: This study underscores the importance of indoor environmental factors in the prevention of pediatric pneumonia. Public health strategies should consider these factors to reduce the incidence of pneumonia in children. Future research needs to be conducted over a broader geographical range and consider a more comprehensive range of factors influencing pediatric pneumonia.

17.
Inorg Chem ; 52(13): 7460-6, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23768124

ABSTRACT

ß-BiB3O6 was compressed in a diamond anvil cell at room temperature and studied using a combinstion of in situ high-pressure Raman scattering and angle-dispersive synchrotron X-ray diffraction. The results reveal that ß-BiB3O6 retains its structure below 9.0 GPa and undergoes a structural phase transition that starts at ~11.5 GPa and finishes at ~18.5 GPa. No other phase transition occurred with increasing pressure up to ~46 GPa. It was also found that the high-pressure phase is different from the already-reported five polymorphs of BiB3O6. Therefore, the new phase is denoted as ζ-BiB3O6, which could be indexed by an orthorhombic unit cell (a ≈ 12.5 Å, b ≈ 6.7 Å, c ≈ 4.0 Å) from the powder XRD pattern collected at 22.2 GPa. Moreover, ζ-BiB3O6 can be quenched to ambient conditions. The investigation of the pressure dependence of the lattice parameters reveals that both ß-BiB3O6 and ζ-BiB3O6 exhibit a large amount of crystallographic anisotropy. An unusual expansion of the c-axis of ζ-BiB3O6 was observed. Assignments for the Raman spectra of ß-BiB3O6, γ-BiB3O6, and δ-BiB3O6 under ambient conditions were also performed. Currently, we cannot solve the crystal structure of ζ-BiB3O6 but give some speculations based on its relationship with ß-BiB3O6.

18.
Dig Dis Sci ; 58(8): 2197-204, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23661031

ABSTRACT

BACKGROUND: Semaphorin 5A, a member of the semaphorin family, was originally identified as an axonal guidance factor functioning during neuronal development. Previously, we showed that the expression of semaphorin 5A might contribute to the metastasis of gastric cancer. However, less information is currently available as to the involvement of uPA in the semaphorin 5A-induced metastasis and invasion of gastric cancer cells. AIM: The present study was designed to test whether semaphorin 5A mediates the invasion and metastasis of gastric cancer via PI3K/Akt/uPA signaling. METHODS: The semaphorin 5A-overexpressing cell was established from the gastric cancer cell line AGS. The effect of semaphorin 5A on the expression of uPA was evaluated by ELISA and Western blotting as well as RT-PCR assays, respectively. Synthetic or natural inhibitors and dominant-negative mutants were used to determine the hierarchical relationship between semaphorin 5A, PI3K/Akt and uPA in the invasion and metastasis of gastric cancer. RESULTS: Overpression of semaphorin 5A enhanced the expression of uPA, and synthetic or natural inhibitors of uPA abolished semaphorin 5A-induced cell migration and invasion. Semaphorin 5A overexpression promoted the phosphorylation of Akt. Blocking effects of PI3K/Akt using pharmacologic inhibitors, dominant-negative mutants abolished the ability of semaphorin 5A to induce uPA expression and cell invasion and migration. CONCLUSION: Semaphorin 5A could promote invasion and metastasis of gastric cancer through the PI3K/Akt/uPA signal transduction pathway. Semaphorin 5A and its regulated molecules could be the potential targets for cancer therapy.


Subject(s)
Gene Expression Regulation, Neoplastic/physiology , Membrane Proteins/metabolism , Nerve Tissue Proteins/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stomach Neoplasms/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Animals , Cell Line, Tumor , Female , Humans , Membrane Proteins/genetics , Mice , Mice, Nude , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasms, Experimental , Nerve Tissue Proteins/genetics , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Semaphorins , Up-Regulation , Urokinase-Type Plasminogen Activator/genetics
19.
Nano Lett ; 12(6): 2685-9, 2012 Jun 13.
Article in English | MEDLINE | ID: mdl-22432731

ABSTRACT

The development of responsive nanomaterials, nanoscale systems that actively respond to stimuli, is one general goal of nanotechnology. Here we develop nanoparticles that can be controllably triggered to synthesize proteins. The nanoparticles consist of lipid vesicles filled with the cellular machinery responsible for transcription and translation, including amino acids, ribosomes, and DNA caged with a photolabile protecting group. These particles served as nanofactories capable of producing proteins including green fluorescent protein (GFP) and enzymatically active luciferase. In vitro and in vivo, protein synthesis was spatially and temporally controllable, and could be initiated by irradiating micrometer-scale regions on the time scale of milliseconds. The ability to control protein synthesis inside nanomaterials may enable new strategies to facilitate the study of orthogonal proteins in a confined environment and for remotely activated drug delivery.


Subject(s)
Crystallization/methods , Nanostructures/chemistry , Nanostructures/ultrastructure , Protein Engineering/methods , Proteins/chemical synthesis , Robotics/methods , Materials Testing , Particle Size , Protein Conformation , Surface Properties
20.
Article in English | MEDLINE | ID: mdl-36800681

ABSTRACT

The cytochrome P450 17α-hydroxylase (P450c17) enzyme, encoded by Cytochrome P450 Family 17 Subfamily A Member 1 (CYP17A1) gene, catalyzes both the 17a-hydroxylation and 17,20-lyase reactions required for the production of cortisol and sex steroids. 17α-hydroxylase/17,20-lyase deficiency (17OHD) is a rare autosomal recessive disease caused by homozygous or compound heterozygous mutations in CYP17A1 gene. 17OHD can be classified into complete form and partial form based on the phenotypes resulting from P450c17 enzyme defects of different severities. Here we report two unrelated girls diagnosed with 17OHD at the age of 15 and 16 respectively. Both patients presented with primary amenorrhea, infantile female external genitalia and absent axillary or pubic hair. Hypergonadotropic hypogonadism was detected in both patients. Besides, Case 1 showed undeveloped breast, primary nocturnal enuresis, hypertension, hypokalemia and reduced 17α-hydroxyprogesterone and cortisol levels, while Case 2 had growth spurt, spontaneous breast development, elevated corticosterone and decreased aldosterone. The chromosome karyotype for both patients was 46, XX. Clinical exome sequencing was used to detect the underlying genetic defect in the patients, and the potential pathogenic mutations were validated by Sanger sequencing of the patients and their parents. The homozygous p.S106P mutation of CYP17A1 gene detected in Case 1 has been reported previously. Although the p.R347C and p.R362H mutations have been reported separately before, their compound heterozygote was firstly identified in Case 2. Based on the clinical, laboratory and genetic findings, Case 1 and Case 2 were definitely diagnosed as complete and partial form of 17OHD respectively. Both patients received estrogen and glucocorticoid replacement therapy. Their uterus and breasts developed gradually, and first menstruation occurred. Hypertension, hypokalemia and nocturnal enuresis in Case 1 were relieved. In conclusion, we described a case of complete 17OHD accompanied by nocturnal enuresis for the first time. Moreover, we identified a new compound heterozygote (p.R347C and p.R362H) of CYP17A1 gene in the case with partial 17OHD.

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