[Clinical manifestations and genetics analysis of collagen type Ⅵ-related myopathy caused by variants in COL6A3 gene]

Objective: To summarize the clinical manifestations and determine the molecular etiology for two collagen type Ⅵ-related myopathy pedigrees. Methods: Two spontaneous collagen type Ⅵ-related myopathy patients were admitted to Department of Neurology, Children's Hospital, Capital Institute of Pediatrics in October 2017. Clinical data of probands and their family members were collected and their genomic DNA was obtained for genetic testing. Next generation sequencing was performed and the variants were verified by the Sanger sequencing in the family members. Results: Target region sequencing indicated that the proband of family 1 has carried a heterozygous variant of COL6A3 gene, c.6229G>C(p.Gly2077Arg), and it was de novo variant confirmed by Sanger-sequencing in the family.The patient 1, a 2-year-three-month old boy, was admitted due to motor retardation at birth. He was defined as early severe Ullrich congenital muscular dystrophy. He never achieved independent ambulation, he had onset of symptoms was found at birth, including diffuse muscle weakness, striking distal joint hyperlaxity, proximal contractures, calcaneal protrusion, kyphosis, and hip dislocation. Serum CK level was elevated slightly and EMG showed neurogenic changes. The patient 2, a 7-year-old girl with a limp for 4 years, carried one de novo variant of COL6A3 gene,c.5169_5177del (p.Glu1724_Leu1726del). This variant results in the deletion of amino acids (1724 to 1726) in α3 chain of collagen Ⅵ, which may disturb the function of this protein.She was diagnosed as Bethlem myopathy with a mild phenotype. She had delayed motor milestones and presented with walking on tiptoe, hypotonia, and ithylordosis. The contracture of proximal joints was not very obvious. Serum CK level was normal and EMG showed myogenic changes.Muscle biopsy revealed muscular dystrophy and muscle magnetic resonance imaging of patient 2 showed vastus lateral is a "sandwich" sign. Immunofluorescence staining for COL6A3 chain in the cultured skin fibroblasts from patients 2 showed decreased deposition compared with control. Conclusions: These two patients were diagnosed as spontaneous collagen type Ⅵ-related myopathy and carried different variants of COL6A3 gene. Different in pathogenetic variants could cause different genetic features and different phenotypes. Collagen type Ⅵ- related myopathy patients have various clinical manifestations. Typical phenotypes include muscular dystrophies, proximal contractures, and distal hyperlaxity. Muscle MRI shows diffuse fatty infiltration of gluteus maximus and thigh muscle. The histological staining showed the low level expression of COL6A3 chain. The seventy of phenotype was related to the genotype.

Temporal variation in zooplankton and phytoplankton community species composition and the affecting factors in Lake Taihu-a large freshwater lake in China

Monitoring diverse components of aquatic ecosystems is vital for elucidation of diversity dynamics and processes, which alter freshwater ecosystems, but such studies are seldom conducted. Phytoplankton and zooplankton are integral components which play indispensable parts in the structure and ecological service function of water bodies. However, few studies were made on how zooplankton and phytoplankton community may respond simultaneously to change of circumstance and their mutual relationship. Therefore, we researched synchronously the phytoplankton communities as well as zooplankton communities based on monthly monitoring data from September 2011 to August 2012 in heavily polluted areas and researched their responses to variation in environmental parameters and their mutual relationship. As indicated by Time-lag analysis (TLA), the long-term dynamics of phytoplankton and zooplankton were undergoing directional variations, what's more, there exists significant seasonal variations of phytoplankton and zooplankton communities as indicated by Non-Metric Multidimensional scaling (NMDS) methods. Also, Redundancy Analysis (RDA) demonstrated that environmental indicators together accounted for 25.6% and 50.1% variance of phytoplankton and zooplankton, respectively, indicating that environmental variations affected significantly on the temporal dynamics of phytoplankton as well as zooplankton communities. What's more, variance partioning suggested that the major environmental factors influencing variation structures of zooplankton communities were water temperature, concentration of nitrogen, revealing the dominating driving mechanism which shaped the communities of zooplankton. It was also found that there was significant synchronization between zooplankton biomass and phytoplankton biomass (expressed as Chl-a concentration), which suggested that zooplankton respond to changes in dynamic structure of phytoplankton community and can initiate a decrease in phytoplankton biomass through grazing in a few months.

Algal uptake of hydrophilic and hydrophobic dissolved organic nitrogen in the eutrophic lakes

Dissolved organic nitrogen (DON) derived from sediments plays an active role in biogeochemical cycling of nutrients in aquatic ecosystems. Sediments from four eutrophic lakes were studied using three-dimensional fluorescence excitation-emission matrix (3DEEM) spectra and supelite XAD-8 macroporous resin separation to investigate the bioavailability of hydrophilic and hydrophobic DON to algae (Microcystis flos-aquae (Wittr.) Kirchner). The results showed that the average loss of DON was <6.0% after dividing DON into hydrophilic and hydrophobic components, demonstrating the utility of XAD-8 resin separation in the study of DON components from lake sediments. The 3DEEM analysis showed that hydrophobic and hydrophilic DON comprised humic- and protein-like materials, respectively. During the incubation period, the bioavailability of hydrophilic DON, which accounted for 59.3%-80.4% of total DON, stimulated algal growth, suggesting that hydrophilic DON was the primary source of organic nitrogen for algae. In contrast, hydrophobic DON increased algal density by only 31.8% of that observed for hydrophilic DON, and had a small (accounted for 20.0%-26.6% of total DON) effect on algal growth over the short-term. The significant differences in algal growth between the two types of DON suggested that they should be considered separately in the eutrophic lake restorations.

[Application value of endoscope in probing chronic wound with sinus tract in clinic]

Objective: To explore the application value of endoscope in probing the chronic wound with sinus tract in clinic. Methods: Twenty-eight chronic wounds with sinus tracts from 27 patients conforming to the inclusion criteria admitted to Outpatient Department of Wound Healing Center of Ruijin Hospital from December 2017 to March 2018 were investigated in a prospective and self-controlled trial. After being cleaned, the diameter of the opening of sinus tract was measured with a rule. A probe was used to measure the depth of a sinus tract according to the touch from the probe extremity in operation, and to measure the depth of a sinus tract that could be observed with naked eyes with the help of a pair of hemostatic forceps. Five minutes later, a probe was inserted deeply into the sinus tract to measure the depth under the endoscopic view combined with touch from the probe extremity in operation. Afterwards, the sinus tract was observed with endoscope, and the depth of the tract which could be observed under the endoscopic view was measured using a probe inserted deeply into the sinus tract. After completion of the above exploration, the sinus tract was infused with contrast agent Omnipaque 350 and scanned by computed tomography (CT) later to obtain its depth. The following indicators were calculated: the ratio of the depth of the sinus tract measured by CT to the diameter of the opening of the sinus tract (hereinafter referred to as the depth/diameter ratio of the sinus tract), the deviation rate comparing the depth of the sinus tract measured by conventional method (measured by probe only) and by endoscope (measured by probe under the endoscope view) with the depth of the sinus tract measured by CT (hereinafter referred to as the deviation rate of the measured depth of the sinus tract), the deviation rate comparing the depth of the sinus tract that could be observed measured by conventional method and by endoscope with the depth of the sinus tract measured by CT (hereinafter referred to as the deviation rate of the depth of the sinus tract that could be observed). Data were processed with paired t test. Pearson correlation analysis was applied to analyze the correlation between the depth/diameter ratio of the sinus tract and the deviation rate of the measured depth of the sinus tract and the deviation rate of the depth of the sinus tract that could be observed by conventional method and by endoscope. Results: The depth/diameter ratio of the sinus tract of this group of wounds was 1-32 (8±7). The deviation rate of the measured depth of the sinus tract and the deviation rate of the depth of the sinus tract that could be observed by conventional method were (19±14)% and (79±18)%, respectively, both obviously larger than (9±9)% and (25±25)% by endoscope (t=3.837, 13.626, P<0.01). Positive correlation existed between the depth/diameter ratio of the sinus tract and the deviation rate of the measured depth of the sinus tract by conventional method, and between the depth/diameter ratio of the sinus tract and the deviation rate of the depth of the sinus tract that could be observed by conventional method and by endoscope (r=0.514, 0.585, 0.651, P<0.01). However, there was no obvious correlation between the depth/diameter ratio of the sinus tract and the deviation rate of the measured depth of the sinus tract by endoscope (r=0.113, P>0.05). Conclusions: Compared with the conventional method, application of endoscope is able to get more accurate data of chronic wounds with sinus tracts and observe the wounds with wider range.

Fluorescence regional integration and differential fluorescence spectroscopy for analysis of structural characteristics and proton binding properties of fulvic acid sub-fractions

Structural characteristics and proton binding properties of sub-fractions (FA₃-FA₁₃) of fulvic acid (FA), eluted stepwise by pyrophosphate buffer were examined by use of fluorescence titration combined with fluorescence regional integration (FRI) and differential fluorescence spectroscopy (DFS). Humic-like (H-L) and fulvic-like (F-L) materials, which accounted for more than 80% of fluorescence response, were dominant in five sub-fractions of FA. Based on FRI analysis, except the response of F-L materials in FA₉ and FA₁₃, maximum changes in percent fluorescence response were less than 10% as pH was increased from 2.5 to 11.5. Contents of carboxylic and phenolic groups were compared for fluorescence peaks of FA sub-fractions based on pH-dependent fluorescence derived from DFS. Static quenching was the dominant mechanism for binding of protons by FA sub-fractions. Dissociation constants (pKa) were calculated by use of results of DFS and the modified Stern-Volmer relationship. The pK_a of H-L, F-L, tryptophan-like and tyrosine-like materials of FA sub-fractions exhibited ranges of 3.17-4.06, 3.12-3.97, 4.14-4.45 and 4.25-4.76, respectively, for acidic pHs. At basic pHs, values of pKa for corresponding materials were in ranges of 9.71-10.24, 9.62-10.99, 9.67-10.31 and 9.33-10.28, respectively. At acidic pH, protein-like (P-L) materials had greater affinities for protons than did either H-L or F-L materials. The di-carboxylic and phenolic groups were likely predominant sites of protonation for both H-L and F-L materials at both acidic and basic pHs. Amino acid groups were significant factors during proton binding to protein-like materials of FA sub-fractions at basic pH.

Using dual isotopes and a Bayesian isotope mixing model to evaluate sources of nitrate of Tai Lake, China

Identification and quantification of sources of nitrate (NO₃^-) in freshwater lakes provide useful information for management of eutrophication and improving water quality in lakes. Dual δ¹⁵N- and δ¹⁸O-NO₃^- isotopes and a Bayesian isotope mixing model were applied to identify sources of NO₃^- and estimate their proportional contributions to concentrations of NO₃^- in Tai Lake, China. In waters of Tai Lake, values for δ¹⁵N-NO₃^- ranged from 3.8 to 10.1‰, while values of δ¹⁸O ranged from 2.2 to 12.0‰. These results indicated that NO₃^- was derived primarily from agricultural and industrial sources. Stable isotope analysis in R called SIAR model was used to estimate proportional contributions from four potential NO₃^- sources (agricultural, industrial effluents, domestic sewage, and rainwater). SIAR output revealed that agricultural runoff provided the greatest proportion (50.8%) of NO₃^- to the lake, followed by industrial effluents (33.9%), rainwater (8.4%), and domestic sewage (6.8%). Contributions of those primary sources of NO₃^- to sub-regions of Tai Lake varied significantly (p < 0.05). For the northern region of the lake, industrial source (35.4%) contributed the greatest proportion of NO₃^-, followed by agricultural runoff (27.4%), domestic sewage (21.3%), and rainwater (15.9%). Whereas for the southern region, the proportion of NO₃^- contributed from agriculture (38.6%) was slightly greater than that contributed by industry (30.8%), which was similar to results for nearby inflow tributaries. Thus, to improve water quality by addressing eutrophication and reduce primary production of phytoplankton, NO₃^- from both nonpoint agricultural sources and industrial point sources should be mitigated. Graphical abstract ᅟ.

Colloidal stability of Fe3O4 magnetic nanoparticles differentially impacted by dissolved organic matter and cations in synthetic and naturally-occurred environmental waters

Better understanding of the colloidal behaviors of nanomaterials impacted by aquatic chemistry parameters is needed for appropriate evaluation of the environmental risks posed by nanomaterials in natural waters. In the study, the colloidal stability of Fe₃O₄ magnetic nanoparticles (Fe-MNPs) was evaluated over a range of chemistry characteristics [e.g., pH, dissolved organic matter (DOM), salt types, cationic strength] in six synthetic water samples. The findings from the synthetic water samples were further examined with eight "real world" environmental water samples. Our results demonstrated that DOM fraction, humic acid (HA), promoted suspension of Fe-MNPs more by hydrophobic interactions in addition to ligand exchange and electrostatic effects compared with fulvic acid (FA). Capability of cations to increase aggregation of Fe-MNPs were in the order of Ca²⁺ > Mg²⁺ >> Na⁺ because of their different degrees of bridging complexation with DOM molecules on particle surfaces. As a key parameter for indicating Fe-MNPs colloidal stability, Zeta (ζ) potentials of Fe-MNPs in these waters samples were well correlated to (R² = 0.880, P < 0.001) the contents, types and adsorption forms of DOM and cations. However, several other factors could also affect the hydrodynamic diameter (HDD) of Fe-MNPs in the "real world" environmental waters. It assumed that ampholytic-DOM molecules such as amino acid- and protein-like molecules caused great aggregation of Fe-MNPs. These findings would be helpful for better understanding and evaluating the colloidal behaviors of nanomaterials when they released into natural water environment, thus could shed light on developing relevant pollution control strategies.

[Advances in postoperative thyroid-stimulating hormone suppression therapy in females with thyroid cancer]

Differentiated thyroid cancer is the most common malignant carcinoma in female population.Postoperative long-term thyroid-stimulating hormone(TSH) suppression therapy can reduce the risk of recurrence for differentiated thyroid cancer and control the progress of the disease, but it also induces simultaneously subclinical hypothyroidism and imposes negative effect on female. In addition to cardiovascular disease, TSH suppression therapy can lead to the alteration of sex hormone metabolism, menstrual disorder, poor influence on pregnancy and osteoporosis. This article reviews the recent studies on postoperative TSH suppression therapy in women with thyroid cancer.

Simulated bioavailability of phosphorus from aquatic macrophytes and phytoplankton by aqueous suspension and incubation with alkaline phosphatase

Bioavailability of phosphorus (P) in biomass of aquatic macrophytes and phytoplankton and its possible relationship with eutrophication were explored by evaluation of forms and quantities of P in aqueous extracts of dried macrophytes. Specifically, effects of hydrolysis of organically-bound P by the enzyme alkaline phosphatase were studied by use of solution ³¹P-nuclear magnetic resonance (NMR) spectroscopy. Laboratory suspensions and incubations with enzymes were used to simulate natural releases of P from plant debris. Three aquatic macrophytes and three phytoplankters were collected from Tai Lake, China, for use in this simulation study. The trend of hydrolysis of organic P (P_o) by alkaline phosphatase was similar for aquatic macrophytes and phytoplankton. Most monoester P (15.3% of total dissolved P) and pyrophosphate (1.8%) and polyphosphate (0.4%) and DNA (3.2%) were transformed into orthophosphate (14.3%). The major forms of monoester P were glycerophosphate (8.8%), nucleotide (2.5%), phytate (0.4%) and other monoesters P (3.6%). Proportions of P_o including condensed P hydrolyzed in phytoplankton and aquatic macrophytes were different, with the percentage of 22.6% and 6.0%, respectively. Proportion of P_o hydrolyzed in debris from phytoplankton was approximately four times greater than that of P_o from aquatic macrophytes, and could be approximately twenty-five times greater than that of P_o in sediments. Thus, release and hydrolysis of P_o, derived from phytoplankton debris would be an important and fast way to provide bioavailable P to support cyanobacterial blooming in eutrophic lakes.

Protonation-dependent heterogeneity in fluorescent binding sites in sub-fractions of fulvic acid using principle component analysis and two-dimensional correlation spectroscopy

Heterogeneous distributions of proton binding sites within sub-fractions of fulvic acid (FA₃-FA₁₃) were investigated by use of synchronous fluorescence spectra (SFS), combined with principle component analysis (PCA) and two-dimensional correlation spectroscopy (2D-COS). Tryptophan-like, fulvic-like and humic-like materials were observed in SFS. Tyrosine-like materials were identified by use of SFS-PCA analysis. Combined information from synchronous-asynchronous maps and dissociation constants (pKa) was used to describe heterogeneity of binding sites for protons within each sub-fraction. Heterogeneous distributions of proton binding sites were observed in fulvic-like, humic-like, tryptophan-like, and tyrosine-like materials of five sub-fractions and even in the single fulvic-like materials in FA₃ and tryptophan-like materials in FA₉ and FA₁₃. Values of pKa of sub-fractions ranged from 2.20 to 5.29, depending on associated wavelengths in synchronous-asynchronous maps and use of the modified Stern-Volmer equation. The larger values of pKa (4.17-5.29) were established for protein-like materials (including tryptophan-like and tyrosine-like materials) in comparison to those (2.20-3.38) for humic-like and fulvic-like materials in sub-fractions. Sequential variations of 274nm (pKa 4.15-5.29)→360-460nm (pKa 2.78-2.39) for FA₅-FA₁₃ revealed that binding of protons to tryptophan-like materials appeared prior to humic-like/fulvic-like materials. In FA₉, protons were preferentially binding to tryptophan-like materials than tyrosine-like materials. In FA₃, protons were preferentially binding to humic-like materials than fulvic-like materials. Relative differences of values of pKa for fluorescent materials within each sub-fraction were consistent with sequential orders derived from asynchronous maps. Such an integrated approach, SFS-PCA/2D-COS, has superior potential for further applications in exploring complex interactions between dissolved organic matter and contaminants in engineered and natural environments.

[Effects of denatured collagen type Ⅰ on differentiation of human fibroblasts into myofibroblasts]

Objective: To investigate the effects of denatured collagen type Ⅰ on differentiation of human fibroblasts into myofibroblasts. Methods: A small amount of normal skin donated by burn patients undergoing scar surgery was collected. Human fibroblasts were obtained by method of explant culture and then sub-cultured. The fourth passage of cells were used in the following experiments. (1) Fibroblasts were divided into normal collagen group and denatured collagen group according to the random number table, with 10 wells in each group. Fibroblasts in normal collagen group were cultured on normal collagen type Ⅰ coated coverslips. Fibroblasts in denatured collagen group were cultured on denatured type Ⅰ collagen coated coverslips. Expression of proliferating cell nuclear antigen (PCNA) was detected by immunohistochemical method, and the percentage of PCNA positive cells was calculated. (2) Another batch of fibroblasts were grouped and treated as in (1), with 12 wells in each group. Proliferation activity of cells was determined with methyl-thiazolyl-tetrazolium colorimetry method. (3) Another batch of fibroblasts were grouped and treated as in (1), and the microfilament morphology of cells was observed by rhodamine-phalloidin staining. (4) Another batch of fibroblasts were grouped and treated as in (1). Expression of α smooth muscle actin (α-SMA) of cells was detected by immunohistochemical method, and expression of OB-cadherin of cells was detected by immunofluorescence method. (5) Another batch of fibroblasts were divided into normal collagen, denatured collagen, and common coverslips groups according to the random number table, with 6 wells in each group. Fibroblasts in normal collagen and denatured collagen groups were treated as in (1), while fibroblasts in common coverslips group were cultured on coverslips without collagen coating. Expressions of α-SMA and OB-cadherin of cells were determined with Western blotting. (6) Another batch of fibroblasts were grouped and treated as in (5), and then the mRNA expressions of collagen type Ⅰ, collagen type Ⅲ, and α-SMA of cells were determined with real-time fluorescent quantitative reverse transcription polymerase chain reaction. Data were processed with t test, one way analysis of variance, and least-significant difference test. Results: (1) The percentage of PCNA positive cells in denatured collagen group was (83±9)%, significantly higher than (29±9)% in normal collagen group (t=13.53, P<0.01). (2) The proliferation activity of fibroblasts in denatured collagen group was 0.32±0.06, significantly higher than 0.25±0.05 in normal collagen group (t=3.06, P<0.01). (3) The microfilament of fibroblasts in normal collagen group was arranged vertically and in parallel way, paralleling the long axis of cells. The microfilament of fibroblasts in denatured collagen group was denser and thicker. (4) Most fibroblasts in normal collagen group showed long shuttle-like shape typically. Morphology of fibroblasts in denatured collagen group changed, and cells were obviously spreading. Expressions of α-SMA and OB-cadherin of fibroblasts in denatured collagen group were stronger than those in normal collagen group. (5) Expressions of α-SMA of fibroblasts in denatured collagen, normal collagen, and common coverslips groups were respectively 1.69±0.41, 0.89±0.27, and 1.46±0.42. Expression of α-SMA of fibroblasts in denatured collagen group was significantly higher than that in normal collagen group (P<0.01). Expressions of OB-cadherin of fibroblasts in denatured collagen, normal collagen, and common coverslips groups were respectively 5.17±0.28, 2.21±0.10, and 4.01±0.56. Expression of OB-cadherin of fibroblasts in denatured group was significantly higher than that in normal collagen group (P<0.01). (6) There was no significant difference in mRNA expression of collagen type Ⅰ of fibroblasts in denatured collagen, normal collagen, and common coverslips groups (F=2.71, P>0.05). The mRNA expressions of collagen type Ⅲ and α-SMA of fibroblasts in normal collagen group were significantly lower than those in denatured collagen group (P<0.01). Conclusions: Denatured collagen type Ⅰ may influence the activity of fibroblasts, thus inducing fibroblasts differentiating into myofibroblasts.

Interactions between stepwise-eluted sub-fractions of fulvic acids and protons revealed by fluorescence titration combined with EEM-PARAFAC

In aquatic environments, pH can control environmental behaviors of fulvic acid (FA) via regulating hydrolysis of functional groups. Sub-fractions of FA, eluted using pyrophosphate buffers with initial pHs of 3.0 (FA₃), 5.0 (FA₅), 7.0 (FA₇), 9.0 (FA₉) and 13.0 (FA₁₃), were used to explore interactions between the various, operationally defined, FA fractions and protons, by use of EEM-PARAFAC analysis. Splitting of peaks (FA₃ and FA₁₃), merging of peaks (FA₇), disappearance of peaks (FA₉ and FA₁₃), and red/blue-shifting of peaks were observed during fluorescence titration. Fulvic-like components were identified from FA₃-FA₁₃, and protein-like components were observed in fractions FA₉ and FA₁₃. There primary compounds (carboxylic-like, phenolic-like, and protein-like chromophores) in PARAFAC components were distinguished based on acid-base properties. Dissociation constants (pK_a) for fulvic-like components with proton ranged from 2.43 to 4.13 in an acidic pH and from 9.95 to 11.27 at basic pH. These results might be due to protonation of di-carboxylate and phenolic functional groups. At basic pH, pK_a values of protein-like components (9.77-10.13) were similar to those of amino acids. However, at acidic pH, pK_a values of protein-like components, which ranged from 3.33 to 4.22, were 1-2units greater than those of amino acids. Results presented here, will benefit understanding of environmental behaviors of FA, as well as interactions of FA with environmental contaminants.

CCR2- and CCR2+ corneal macrophages exhibit distinct characteristics and balance inflammatory responses after epithelial abrasion

Macrophages are distributed throughout the body and are crucial for the restoration of damaged tissues. However, their characteristics in the cornea and roles in the repair of corneal injures are unclear. Here we show that corneal macrophages can be classified as CCR2^- macrophages, which already exist in the cornea at embryonic day 12.5 (E12.5) and are similar to yolk sac-derived macrophages, microglia, in phenotype and gene expression, and CCR2⁺ macrophages, which do not appear in the cornea until E17.5. At a steady state, CCR2^- corneal macrophages have local proliferation capacity and are rarely affected by monocytes; however, following corneal epithelial abrasion, most CCR2^- corneal macrophages are replaced by monocytes. In contrast, CCR2⁺ macrophages are repopulated by monocytes under both a steady-state condition and following corneal wounding. Depletion of CCR2⁺ macrophages decreases corneal inflammation after epithelial abrasion, whereas depletion of CCR2^- macrophages increases inflammation of the injured cornea. Loss of either cell type results in a delay in corneal healing. These data indicate that there are two unique macrophage populations present in the cornea, both of which participate in corneal wound healing by balancing the inflammatory response.

Using solid 13C NMR coupled with solution 31P NMR spectroscopy to investigate molecular species and lability of organic carbon and phosphorus from aquatic plants in Tai Lake, China

Forms and labilities of plant-derived organic matters (OMs) including carbon (C) and phosphorus (P) were fundamental for understanding their release, degradation and environmental behaviour in lake ecosystems. Thus, solid ¹³C and solution ³¹P nuclear magnetic resonance (NMR) spectroscopy were used to characterize biomass of six aquatic plants in Tai Lake, China. The results showed that carbohydrates (61.2% of the total C) were predominant C functional group in the solid ¹³C NMR spectra of plant biomass, which may indicate high lability and bioavailability of aquatic plants-derived organic matter in lakes. There was 72.6-103.7% of the total P in aquatic plant biomass extracted by NaOH-EDTA extracts. Solution ³¹P NMR analysis of these NaOH-EDTA extracts further identified several molecular species of P including orthophosphate (50.1%), orthophosphate monoesters (46.8%), DNA (1.6%) and pyrophosphate (1.4%). Orthophosphate monoesters included β-glycerophosphate (17.7%), hydrolysis products of RNA (11.7%), α-glycerophosphate (9.2%) and other unknown monoesters (2.1%). Additionally, phytate, the major form of organic P in many lake sediments, was detected in floating plant water poppy. These inorganic P (e.g. orthophosphate and pyrophosphate) and organic P (e.g. diester and its degradation products) identified in plant biomass were all labile and bioavailable P, which would play an important role in recycling of P in lakes. These results increased knowledge of chemical composition and bioavailability of OMs derived from aquatic plants in lakes.

Frontiers of water oxidation: the quest for true catalysts

Development of advanced analytical techniques is essential for the identification of water oxidation catalysts together with mechanistic studies.

[Effects of severe hypoxia and low concentration of serum protein on the function of human hypertrophic scar fibroblasts]

Objective: To simulate the environmental factors during the process of formation and evolution of hypertrophic scar, so as to explore the effects of moderate and severe hypoxia and low concentration of serum protein on the function of human hypertrophic scar fibroblasts (HSFs). Methods: Human HSFs were routinely cultured. Cells of the 3rd to the 6th passage were divided into 10.0% oxygen+ 10.0% fetal calf serum (FCS), 5.0% oxygen+ 5.0% FCS, and 0.5% oxygen+ 0.5% FCS groups according to the random number table. After being cultured with DMEM nutrient solution with no FCS for 24 h, the cells were cultured with the corresponding volume fraction of oxygen and FCS. Cell proliferation activity was determined with methyl-thiazole-tetrazolium assay (denoted as actual cell number). Content of total collagen was detected with Sirius red staining method (denoted as absorbance value). Protein expression levels of hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF), transforming growth factor β₁ (TGF-β₁), B-cell lymphoma 2 (Bcl-2), and P53 were determined with Western blotting (denoted as ratio of gray value). Cell apoptosis rate was detected by in situ end labeling method. The sample numbers of each group in the above experiments were all 3. Data were processed with Kruskal-Wallis test and Dunnett test. Results: (1) Compared with 11 000±1 306 in 10.0% oxygen+ 10.0% FCS group, the cell proliferation activity was higher in 5.0% oxygen+ 5.0% FCS group (13 290±1 500, P<0.05), but lower in 0.5% oxygen+ 0.5% FCS group (6 999±765, P<0.05). (2) Compared with 0.039 6±0.004 2 in 10.0% oxygen+ 10.0% FCS group, the content of total collagen of cells was higher in 5.0% oxygen+ 5.0% FCS group (0.051 6±0.005 1, P<0.05), but lower in 0.5% oxygen+ 0.5% FCS group (0.015 6±0.002 4, P<0.05). (3) Compared with those in 10.0% oxygen+ 10.0% FCS group, the protein expression levels of HIF-1α, VEGF, TGF-β₁, and Bcl-2 were increased (with P values below 0.05), with no obvious difference in protein expression level of P53 in 5.0% oxygen+ 5.0% FCS group (P>0.05), whereas the protein expression levels of HIF-1α, VEGF, TGF-β₁, and Bcl-2 were decreased (with P values below 0.05), while the protein expression level of P53 was increased in 0.5% oxygen+ 0.5% FCS group (P<0.05). (4) Compared with (1.2±0.9)% in 10.0% oxygen+ 10.0% FCS group, the cell apoptosis rate in 5.0% oxygen+ 5.0% FCS group showed no significant difference [(2.6±0.9)%, P>0.05], while it was significantly increased in 0.5% oxygen+ 0.5% FCS group [(13.3±4.1)%, P<0.05]. Conclusions: Severe hypoxia and low concentration of serum protein can inhibit proliferation activity and production of total collagen of human HSFs and induce their apoptosis.

Pre- and undiagnosed-hypertension in urban Chinese adults: a population-based cross-sectional study

Hypertension is common in adults and often undiagnosed, and the prevalence of pre- and undiagnosed-hypertension remains unclear. We aimed to investigate the prevalence of pre- and undiagnosed-hypertension and their correlates among urban Chinese adults. A total of 7435 participants aged 20-79 were included in this study. Data on demographics, lifestyle and medical history were collected through a structured interview. Pre- and undiagnosed-hypertension was defined as systolic blood pressure/ diastolic blood pressure (SBP/DBP) of 120-139/80-89 mm Hg and SBP⩾140 mm Hg and/or DBP⩾90 mm Hg, respectively, in participants without a history of hypertension and use of antihypertensive medication. Prevalence rates were calculated and standardized using local age- and gender-specific census data. Data were analysed using multinomial logistic regression with adjustment for potential confounders. Of all the participants, 2726 (36.7%) were diagnosed with pre-hypertension and 919 (12.3%) with undiagnosed-hypertension. Undiagnosed-hypertension accounted for 37.3% of all participants with hypertension. The prevalence of pre-hypertension gradually decreased with age, while undiagnosed-hypertension increased, although presenting different changing patterns among men and women. In a fully adjusted multinomial logistic regression, age, male sex, low socio-economic status (SES), abdominal obesity, alcohol drinking, physical inactivity and type 2 diabetes mellitus (T2DM) were significantly associated with increased odds of pre- and undiagnosed-hypertension. In conclusions, the prevalence of pre- and undiagnosed-hypertension was ~50% among urban Chinese adults. Abdominal obesity, low SES, alcohol drinking, physical inactivity and T2DM may be indicators for pre- and undiagnosed-hypertension.

Methodological difificulties in rehabilitation research

This paper presents an overview of some of the pitfalls and suggests ways of improving the quality of research into rehabilitation after stroke. The aims of rehabilitation are outlined and methodological problems inherent in this area discussed, including spontaneous recovery, multidimensional outcomes, definition of treatment and placebo effects. Major weaknesses found in the rehabilitation literature are identified and recommendations for improvement made, including the need for comparable controls, adequate numbers, appropriate outcome measures, clear definition of therapy, generalizability, and a concern for the cost-effectiveness of stroke rehabilitation packages. The field of rehabilitation is still relatively new and idiosyncratic in form and content. Thus it still provides opportunities for research into its relative effectiveness before current practices in rehabilitation become entrenched in medical practice and folklore. Adequate funding support for improved, multicentre clinical trials in rehabilitation is essential.

The clinical diagnostic value of target biopsy using narrow-band imaging endoscopy and accurate laryngeal carcinoma pathologic specimen acquisition

OBJECTIVE

To estimate the clinical significance of target biopsy for clinical diagnosis and determine accurate laryngeal lesion pathologic specimen acquisition via narrow-band imaging (NBI) endoscopy.

METHODS

A total of 138 samples from patients with laryngeal lesions (carcinoma, 118; hyperplasia, 3; mild dysplasia, 2; moderate dysplasia, 5; severe dysplasia, 5; vocal cord polyp, 1; and inflammatory lesion, 4) were collected from the Department of Otolaryngology Head and Neck Surgery of Tianjin Union Medical Center from 1 January 2013 to 1 February 2015. All patients were divided into the regular biopsy and NBI target biopsy groups; the imaging data were recorded and patient samples were biopsied. Pathologic diagnoses were used to evaluate the accuracies of regular and target biopsy.

RESULTS

Based on the pathologic diagnosis, NBI target pathology yielded an accurate laryngeal lesion pathologic specimen acquisition rate of 95.6% (65/68), significantly higher than that yielded by regular biopsy (75.7%, 53/70; χ² = 10.99, P = 0.001). In the NBI target pathology group, the correct accurate pathologic specimen acquisition rates at laryngeal cancer diagnostic stages 0 (Tis), I and II were 100%, 100% and 85.71%, respectively, which were higher than the corresponding rates in the regular biopsy group (0%, χ² = 10.000, P = 0.002; 25%, χ² = 5.625, P = 0.018; and 38.46%, χ² = 6.454, P = 0.011, respectively).

CONCLUSIONS

In cases of laryngeal carcinoma, NBI endoscopy plays an important role in clinical diagnosis and accurate pathologic specimen acquisition and could be a regular clinical method for laryngeal lesion detection.