Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Light Response Curves in Land Plants

Light is the driving force for photosynthesis. Two techniques are commonly employed to help characterize the relationship between the light environment and photosynthesis in plants.Chlorophyll a fluorescence analysis is used to examine both the capacity for and the efficiency of the conversion of absorbed light into energy for photosynthesis. Additionally, gas exchange analysis is used to assess the utilization of that energy for carbon fixation. These techniques are used either in isolation or in combination to acquire light response curves that measure the response of the plant to sequential changes in irradiance. Light response curves can help users understand photosynthetic mechanisms, evaluate how plants respond to light conditions, or assess the extent of physiological plasticity within plants. In this chapter, we provide a generalized method for acquiring light response curves suitable for both chlorophyll a fluorescence and gas exchange techniques using commercially available apparatus. Depending on the equipment available, these methods can be applied individually or combined to acquire data simultaneously. The methods are broadly applicable to most land plants but are ideally suited to help those that are unfamiliar with these techniques.

Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales^1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare⁴ in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet⁵, plasma instabilities^6,7 or orbital motion in an accretion disc^7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. ⁹). BL Lac, the prototype of a subclass of blazars¹⁰, is powered by a 1.7 × 10⁸ M_Sun (ref. ¹¹) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. ¹²)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities⁶ near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Targeted knockdown of ribulose-1, 5-bisphosphate carboxylase-oxygenase in rice mesophyll cells

We generated antisense constructs targeting two of the five Rubisco small subunit genes (OsRBCS2 and 4) which account for between 30-40 % of the RBCS transcript abundance in leaf blades. The constructs were driven by a maize phosphoenolpyruvate carboxylase (PEPC) promoter known to have enriched expression in mesophyll cells (MCs). In the resulting lines leaf, Rubisco protein content was reduced by between 30-50 % and CO₂ assimilation rate was limited under photorespiratory and non-photorespiratory conditions. A relationship between Rubisco protein content and CO₂ assimilation rate was found. This was associated with a significant reduction in dry biomass accumulation and grain yield of between 37-70%. In addition to serving as a resource for reducing Rubisco accumulation in a cell-preferential manner, these lines allow us to characterize gene function and isoform specific suppression on photosynthesis and growth. Our results suggest that the knockdown of multiple genes is required to completely reduce Rubisco accumulation in MCs.

A low CO2-responsive mutant of Setaria viridis reveals that reduced carbonic anhydrase limits C4 photosynthesis

In C4 species, β-carbonic anhydrase (CA), localized to the cytosol of the mesophyll cells, accelerates the interconversion of CO2 to HCO3-, the substrate used by phosphoenolpyruvate carboxylase (PEPC) in the first step of C4 photosynthesis. Here we describe the identification and characterization of low CO2-responsive mutant 1 (lcr1) isolated from an N-nitroso-N-methylurea- (NMU) treated Setaria viridis mutant population. Forward genetic investigation revealed that the mutated gene Sevir.5G247800 of lcr1 possessed a single nucleotide transition from cytosine to thymine in a β-CA gene causing an amino acid change from leucine to phenylalanine. This resulted in severe reduction in growth and photosynthesis in the mutant. Both the CO2 compensation point and carbon isotope discrimination values of the mutant were significantly increased. Growth of the mutants was stunted when grown under ambient pCO2 but recovered at elevated pCO2. Further bioinformatics analyses revealed that the mutation has led to functional changes in one of the conserved residues of the protein, situated near the catalytic site. CA transcript accumulation in the mutant was 80% lower, CA protein accumulation 30% lower, and CA activity ~98% lower compared with the wild type. Changes in the abundance of other primary C4 pathway enzymes were observed; accumulation of PEPC protein was significantly increased and accumulation of malate dehydrogenase and malic enzyme decreased. The reduction of CA protein activity and abundance in lcr1 restricts the supply of bicarbonate to PEPC, limiting C4 photosynthesis and growth. This study establishes Sevir.5G247800 as the major CA allele in Setaria for C4 photosynthesis and provides important insights into the function of CA in C4 photosynthesis that would be required to generate a rice plant with a functional C4 biochemical pathway.

Nuclear export protein CSE1L interacts with P65 and promotes NSCLC growth via NF-κB/MAPK pathway

Non-small cell lung cancer (NSCLC) is characterized with high morbidity and mortality, mainly due to frequent recurrence and metastasis. However, the underlying molecular mechanisms of NSCLC tumorigenesis are largely unclear. Through data mining in the ONCOMINE and Gene Expression Omnibus (GEO) databases, the expression of CSE1L (chromosome segregation like 1 protein/CAS), an exportin, was identified to be significantly upregulated in NSCLC and positively associated with poor prognosis of patients. By use of in vitro and in vivo gain- and loss-of-function experiments, we found that CSE1L can promote NSCLC cell proliferation while inhibiting cell apoptosis. Through immunoprecipitation and mass spectrometry experiments, we demonstrated that CSE1L interacted with RELA (named as P65) and affected its location in the nucleus. Moreover, we found that one of the mechanisms by which CSE1L promotes proliferation and inhibits apoptosis is through activating the nuclear factor-κB (NF-κB)/mitogen-activated protein kinase (MAPK) signaling pathway. In summary, our findings indicated an oncogenic role of CSE1L in NSCLC tumorigenesis.

Overexpression of the chloroplastic 2-oxoglutarate/malate transporter disturbs carbon and nitrogen homeostasis in rice

The chloroplastic 2-oxaloacetate (OAA)/malate transporter (OMT1 or DiT1) takes part in the malate valve that protects chloroplasts from excessive redox poise through export of malate and import of OAA. Together with the glutamate/malate transporter (DCT1 or DiT2), it connects carbon with nitrogen assimilation, by providing 2-oxoglutarate for the GS/GOGAT (glutamine synthetase/glutamate synthase) reaction and exporting glutamate to the cytoplasm. OMT1 further plays a prominent role in C4 photosynthesis: OAA resulting from phosphoenolpyruvate carboxylation is imported into the chloroplast, reduced to malate by plastidic NADP-malate dehydrogenase, and then exported for transport to bundle sheath cells. Both transport steps are catalyzed by OMT1, at the rate of net carbon assimilation. To engineer C4 photosynthesis into C3 crops, OMT1 must be expressed in high amounts on top of core C4 metabolic enzymes. We report here high-level expression of ZmOMT1 from maize in rice (Oryza sativa ssp. indica IR64). Increased activity of the transporter in transgenic rice was confirmed by reconstitution of transporter activity into proteoliposomes. Unexpectedly, overexpression of ZmOMT1 in rice negatively affected growth, CO2 assimilation rate, total free amino acid content, tricarboxylic acid cycle metabolites, as well as sucrose and starch contents. Accumulation of high amounts of aspartate and the impaired growth phenotype of OMT1 rice lines could be suppressed by simultaneous overexpression of ZmDiT2. Implications for engineering C4 rice are discussed.

Ethnic Disparities in Dental Caries among Adolescents in China

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health-related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10-1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25-1.67), Tibetan (PRR, 1.39; 95% CI, 1.3-1.48), and Yi (PRR, 1.24; 95% CI, 1.04-1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.

Exploring Effective Sensory Experience in the Environmental Design of Sustainable Cafés

The aim of this study was to explore and construct spatial indicators suitable for green café ambience. The indicators were further empirically verified. A three-round questionnaire survey, based on the Delphi method, was conducted with 15 experts, including university professors (food and beverage services management and interior environmental design), café operators, and personnel from government agencies. Data were collected, and the results on the characteristics of the repeated feedback from the experts were convergent. Thirty-six indicators suitable for the design of green café ambience were extracted, of which 17 were verified by actual cafés as highly operable. The five-sense indicators of sustainable green ambience design obtained in this study can facilitate positive customer experiences and enhance the appeal of maintaining sustainable green trends for cafés. These indicators can also provide references for café operators in business planning and green café ambience design.

The Relations Among Physical Indicators, Cognitive Status, Community Participation, and Depression of the Frail Male Elderly in Taiwan

This study explored the basic attributes, physiological indices, cognitive states, and community participation of older male outpatients with frailty for predicting depression. Questionnaires were collected using purposive sampling from a medical clinic in a teaching hospital in northern Taiwan. One hundred and ninety frail men enrolled as participants. The results revealed that older male adults with frailty, the age, residence, income, self-reported health status, alcohol consumption, total instrumental activities of daily living (IADL) scores in physiological indices, IADL grouping, cognitive state score, each Mini-Mental State Examination category, and involvement and dedication scores exhibited statistical differences from depression scores. Depression determinants, such as an excellent and normal self-reported health status and IADL total score, could predict the depression status of male older adults with frailty. Nursing personnel should assess the self-reported health status and self-care ability of male older adults with frailty early to prevent or delay geriatric depression.

Increased vasculogenesis of endothelial cells in hyaluronic acid augmented fibrin-based natural hydrogels - from in vitro to in vivo models

Vascularisation efficiency plays an essential role in the success of bulk transplantation, while biocompatibility and safety are major concerns in clinical applications. Fibrin-based hydrogels have been exploited as scaffolds for their advantages in biocompatibility, degradability and mass transportation in various forms. However, the mechanical strength and degree of vascularisation remain unsatisfactory for clinical usage. An interpenetrating hydrogel was developed by adding hyaluronic acid (HA) to a fibrin-based natural hydrogel. The vasculogenesis of endothelial cells (human umbilical vein endothelial cells, HUVECs) was characterised within the gel using both in vitro and in vivo animal studies. The in vitro vascular morphology analysis showed 17.9 % longer mean tube length and 14.3 % higher average thickness in 7 d cultivation within the HA-supplemented hydrogel. The in vivo results showed 51.6 % larger total tube area, 1.8 × longer average tube length and 81.6 % higher cell number in the HA-supplemented hydrogel compared to the hydrogel without HA. The experimental results demonstrated better vascularisation and cell recruitment in the HA- supplemented hydrogel. The material properties of the hydrogels were also analysed using atomic force microscopy (AFM). The results revealed 3.7 × higher elasticity of the HA-supplemented hydrogel, which provided better mechanical strength and support for easy handling during procedures. With the demonstrated advantages, the developed hydrogels showed promise for exploitation in various practical clinical applications.

A Partial C4 Photosynthetic Biochemical Pathway in Rice

Introduction of a C₄ photosynthetic pathway into C₃ rice (Oryza sativa) requires installation of a biochemical pump that concentrates CO₂ at the site of carboxylation in modified bundle sheath cells. To investigate the feasibility of this, we generated a quadruple line that simultaneously accumulates four of the core C₄ photosynthetic enzymes from the NADP-malic enzyme subtype, phosphoenolpyruvate carboxylase (ZmPEPC), NADP-malate dehydrogenase (ZmNADP-MDH), NADP-malic enzyme (ZmNADP-ME), and pyruvate phosphate dikinase (ZmPPDK). This led to enhanced enzyme activity and mild phenotypic perturbations but was largely neutral in its effects on photosynthetic rate. Measurements of the flux of ¹³CO₂ through photosynthetic metabolism revealed a significant increase in the incorporation of ¹³C into malate, consistent with increased fixation of ¹³CO₂ via PEP carboxylase in lines expressing the maize PEPC enzyme. However, there was no significant differences in labeling of 3-phosphoglycerate (3PGA) indicating that there was no carbon flux through NADP-ME into the Calvin-Benson cycle. There was also no significant difference in labeling of phosphoenolpyruvate (PEP) indicating that there was no carbon flux through PPDK. Crossing the quadruple line with a line with reduced glycine decarboxylase H-protein (OsGDCH) abundance led to a photosynthetic phenotype characteristic of the reduced OsGDCH line and higher labeling of malate, aspartate and citrate than in the quintuple line. There was evidence of ¹³C labeling of aspartate indicating ¹³CO₂ fixation into oxaloacetate by PEPC and conversion to aspartate by the endogenous aspartate aminotransferase activity. While Kranz anatomy or other anatomical modifications have not yet been installed in these plants to enable a fully functional C₄ cycle, these results demonstrate for the first-time a partial flux through the carboxylation phase of NADP-ME C₄ metabolism in transgenic rice containing two of the key metabolic steps in the C₄ pathway.

Transgenic maize phosphoenolpyruvate carboxylase alters leaf-atmosphere CO2 and 13CO2 exchanges in Oryza sativa

The engineering process of C4 photosynthesis into C3 plants requires an increased activity of phosphoenolpyruvate carboxylase (PEPC) in the cytosol of leaf mesophyll cells. The literature varies on the physiological effect of transgenic maize (Zea mays) PEPC (ZmPEPC) leaf expression in Oryza sativa (rice). Therefore, to address this issue, leaf-atmosphere CO2 and 13CO2 exchanges were measured, both in the light (at atmospheric O2 partial pressure of 1.84 kPa and at different CO2 levels) and in the dark, in transgenic rice expressing ZmPEPC and wild-type (WT) plants. The in vitro PEPC activity was 25 times higher in the PEPC overexpressing (PEPC-OE) plants (~20% of maize) compared to the negligible activity in WT. In the PEPC-OE plants, the estimated fraction of carboxylation by PEPC (β) was ~6% and leaf net biochemical discrimination against 13CO2[Formula: see text] was ~ 2‰ lower than in WT. However, there were no differences in leaf net CO2 assimilation rates (A) between genotypes, while the leaf dark respiration rates (Rd) over three hours after light-dark transition were enhanced (~ 30%) and with a higher 13C composition [Formula: see text] in the PEPC-OE plants compared to WT. These data indicate that ZmPEPC in the PEPC-OE rice plants contributes to leaf carbon metabolism in both the light and in the dark. However, there are some factors, potentially posttranslational regulation and PEP availability, which reduce ZmPEPC activity in vivo.

[Analysis of intratesticular condition in micro-dissection testicular sperm extraction era]

OBJECTIVE

To summarizes the intratesticular condition of azoospermia patients, to understand azoospermia more intuitively, and improve the ability of clinical doctors to predict the success rate of microsperm extraction in azoospermia patients.

METHODS

Azoospermia patients (excluding Klinefelter's syndrome) who underwent a micro-TESE during January 2014 and January 2018 in a single center were enrolled. The types of seminiferous tubules were summarized, and the clinical characteristics of different types of seminiferous tubules compared with the success rates of sperm extraction. In this study, 472 cases of non-obstructive azoospermia (excluding Klinefelter's syndrome) were analyzed by SPSS 21.0 software package. Relevant data were expressed by median(minimum,maximum).t-test was used to compare the difference of success rate of sperm extraction between each group and the group with the lowest rate (a type).

RESULTS

The 472 patients with non-obstructive azoospermia underwent micro-TESE. The mean age of the patients was 31 (23, 46) years, the mean testicular size was 10 (1, 20) mL, the mean FSH was 15.4 (1.21, 68.4) IU/L, the mean T was 8.34 (0.69, 30.2) nmol/L, and totally 202 patients achieved success in micro-TESE (42.7%, 202/472). According to the seminiferous tubules seen during the operation, they were divided into the following six types: Class a, seminiferous tubules developed well and uniformly; Class b, seminiferous tubules developed well, occasionally slightly thick; Class c, seminiferous tubules were generally thin; Class d, seminiferous tubules basically atrophied, occasionally well-developed seminiferous tubules; Class e, all seminiferous tubules atrophied; Class f, seminiferous tubules were infiltrated by yellow substances. The success rate of micro-TESE varied greatly among different types of the patients. A total of 78 patients with type a were 29 (24, 40) years old, FSH 11.1 (1.21, 15.8) IU/L, T 10.2 (3.29, 26.5) nmol/L), and testicular size 12 (12, 20) mL. The successful rate of sperm extraction was 6.41%; 82 patients with type b were 31 (23, 42) years old, FSH 13.8 (3.23, 19.6) IU/L, T 9.44 (3.58, 30.2) nmol/L), and testicular size 12(8,15) mL. The successful rate of sperm extraction was 74.39%; There were 162 patients in group c, aged 31 (25, 40), FSH 19.6 (9.28, 26.6) IU/L, T 8.75 (5.66, 18.6) nmol/L, and testicular size 8 (5, 12) mL. The successful rate of sperm extraction was 45.06%. There were 36 patients in group d, aged 25 (23,38) years and FSH 28.5 (19.3, 45.6) IU/L, T 6.52 (2.12, 9.83) nmol/L, and testicular size 5 (3, 8) mL, and the success rate of sperm extraction was 94.44%. 26 patients with type e were 28(23, 46) years old, FSH 31.3 (18.5, 68.4) IU/L, T 6.72 (0.69, 18.2) nmol/L, and testicular size 5 (1, 8) mL. The success rate of sperm extraction was 45.38%. 88 patients with type f were 29 (24, 38) years old, FSH 18.5 (5.23, 31.6) IU / L, T 8.32 (3.58, 16.5) nmol/L, and testicular size 12 (6, 20) mL. The success rate of sperm extraction was 28.41%.

CONCLUSION

The success rate of micro-TESE in different types of seminiferous tubules in testis can be helpful to the judgement of the surgeon during the operation.

Knockdown of glycine decarboxylase complex alters photorespiratory carbon isotope fractionation in Oryza sativa leaves

The influence of reduced glycine decarboxylase complex (GDC) activity on leaf atmosphere CO2 and 13CO2 exchange was tested in transgenic Oryza sativa with the GDC H-subunit knocked down in leaf mesophyll cells. Leaf measurements on transgenic gdch knockdown and wild-type plants were carried out in the light under photorespiratory and low photorespiratory conditions (i.e. 18.4 kPa and 1.84 kPa atmospheric O2 partial pressure, respectively), and in the dark. Under approximately current ambient O2 partial pressure (18.4 kPa pO2), the gdch knockdown plants showed an expected photorespiratory-deficient phenotype, with lower leaf net CO2 assimilation rates (A) than the wild-type. Additionally, under these conditions, the gdch knockdown plants had greater leaf net discrimination against 13CO2 (Δo) than the wild-type. This difference in Δo was in part due to lower 13C photorespiratory fractionation (f) ascribed to alternative decarboxylation of photorespiratory intermediates. Furthermore, the leaf dark respiration rate (Rd) was enhanced and the 13CO2 composition of respired CO2 (δ13CRd) showed a tendency to be more depleted in the gdch knockdown plants. These changes in Rd and δ13CRd were due to the amount and carbon isotopic composition of substrates available for dark respiration. These results demonstrate that impairment of the photorespiratory pathway affects leaf 13CO2 exchange, particularly the 13C decarboxylation fractionation associated with photorespiration.

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms

OBJECTIVES

To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy （FTIR-MSP） combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages.

METHODS

Electrical skin injury model was established on swines. The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control. Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired. With the combination of machine learning algorithms such as principal component analysis （PCA） and partial least squares-discriminant analysis （PLS-DA）, different spectral bands were selected （full band 4 000-1 000 cm^-1 and sub-bands 4 000-3 600 cm^-1, 3 600-2 800 cm^-1, 2 800-1 800 cm^-1, and 1 800-1 000 cm^-1）, and various pretreatment methods were used such as orthogonal signal correction （OSC）, standard normal variables （SNV）, multivariate scatter correction （MSC）, normalization, and smoothing. Thus, the model was optimized, and the classification effects were compared.

RESULTS

Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups. PLS-DA based on the 3 600-2 800 cm^-1 band was used to identify the different voltages induced skin injuries. The OSC could further optimize the robustness of the 3 600-2 800 cm^-1 band model.

CONCLUSIONS

It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

Current Research and Prospects on Postmortem Interval Estimation

The researches on postmortem interval （PMI） estimation are very important and meaningful in forensic science. PMI estimation is also an important issue that must be solved in practice of forensic pathology. There are many defects existing in traditional methods for PMI estimation, so it is imperative to introduce new pathways. With the emergence of various new technologies, the researches on PMI estimation have a tendency from simple to complex with a growth of data. The present review firstly summarizes a series of methods used for PMI estimation, and then gives an outlook for the application of artificial intelligence algorithms in this field.

High-throughput chlorophyll fluorescence screening of Setaria viridis for mutants with altered CO2 compensation points

To assist with efforts to engineer a C4 photosynthetic pathway into rice, forward-genetic approaches are being used to identify the genes modulating key C4 traits. Currently, a major challenge is how to screen for a variety of different traits in a high-throughput manner. Here we describe a method for identifying C4 mutant plants with increased CO2 compensation points. This is used as a signature for decreased photosynthetic efficiency associated with a loss of C4 function. By exposing plants to a CO2 concentration close to the CO2 compensation point of a wild-type plant, individuals can be identified from measurements of chlorophyll a fluorescence. We use this method to screen a mutant population of the C4 monocot Setaria viridis (L.)P.Beauv. generated using N-nitroso-N-methylurea (NMU). Mutants were identified at a frequency of 1 per 157 lines screened. Forty-six candidate lines were identified and one line with a heritable homozygous phenotype selected for further characterisation. The CO2 compensation point of this mutant was increased to a value similar to that of C3 rice. Photosynthesis and growth was significantly reduced under ambient conditions. These data indicate that the screen was capable of identifying mutants with decreased photosynthetic efficiency. Characterisation and next-generation sequencing of all the mutants identified in this screen may lead to the discovery of novel genes underpinning C4 photosynthesis. These can be used to engineer a C4 photosynthetic pathway into rice.

[Effects of Temperature on FTIR Spectral Characteristics of Renal Tissue in Rats after Death]

OBJECTIVES

To analyse the Fourier transform infrared （FTIR） spectral data of renal tissue at different temperatures in rats after death, and to explore the effects of temperature on the FTIR spectral characteristics of renal tissue.

METHODS

The rats were sacrificed by cervical dislocation and placed at 4 ℃, 20 ℃ and 30 ℃. The FTIR spectral data of renal tissue were collected at different time points and analysed by data mining method.

RESULTS

The principal component analysis （PCA） results showed that there were significant trends of clustering in the samples of partial time point at 4 ℃, 20 ℃ and 30 ℃. Partial least square （PLS） regression models were established with the spectral data at three temperature groups. The performance of PLS regression models in 20 ℃ and 30 ℃ groups were more superior than that in 4 ℃ group, and the stability of the model in 20 ℃ group was better than that in 30 ℃ group.

CONCLUSIONS

There are differences in the FTIR spectral characteristics of renal tissue of rats after death at different temperatures. Temperature has a major impact on the performance of FTIR spectral PLS regression model. Therefore, in order to improve the accuracy of postmortem interval estimation, the effects of temperature on the model should be considered in the related study by spectral method.

Single-fabrication-step Ge nanosphere/SiO2/SiGe heterostructures: a key enabler for realizing Ge MOS devices

We report channel and strain engineering of self-organized, gate-stacking heterostructures comprising Ge-nanosphere gate/SiO₂/SiGe-channels. An exquisitely-controlled dynamic balance between the concentrations of oxygen, Si, and Ge interstitials was effectively exploited to simultaneously create these heterostructures in a single oxidation step. Process-controlled tunability of the channel length (5-95 nm diameters for the Ge-nanospheres), gate oxide thickness (2.5-4.8 nm), as well as crystal orientation, chemical composition and strain engineering of the SiGe-channel was achieved. Single-crystalline (100) Si_1-x Ge _x shells with Ge content as high as x = 0.85 and with a compressive strain of 3%, as well as (110) Si_1-x Ge _x shells with Ge content of x = 0.35 and corresponding compressive strain of 1.5% were achieved. For each crystal orientation, our high Ge-content, highly-stressed SiGe shells feature a high degree of crystallinity and thus, provide a core 'building block' required for the fabrication of Ge-based MOS devices.

[Establishment of the Mathematical Model for PMI Estimation Using FTIR Spectroscopy and Data Mining Method]

OBJECTIVES

To analyse the relationship between Fourier transform infrared （FTIR） spectrum of rat's spleen tissue and postmortem interval （PMI） for PMI estimation using FTIR spectroscopy combined with data mining method.

METHODS

Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method.

RESULTS

The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis （PCA） showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis （PLS-DA） and support vector machine classification （SVMC） effectively divided the spectrum samples with different PMI into four categories （0-24 h, 48-72 h, 96-120 h and 144-168 h）. The determination coefficient （R²） of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration （RMSEC） and root mean square error of cross validation （RMSECV） were 9.90 h and 11.39 h respectively. In prediction set, the R² was 0.97, and the root mean square error of prediction （RMSEP） was 10.49 h.

CONCLUSIONS

The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation.

Increased risk of a herpes zoster attack in patients receiving androgen deprivation therapy for prostate cancer

This study aimed to examine the association of herpes zoster (HZ) with androgen deprivation therapy (ADT) use among patients with prostate cancer (PC), using a population-based data set. The study sample for this study was retrieved from the Taiwan Longitudinal Health Insurance Database 2005. We selected 877 patients with PC who had received ADT as the study group, while 849 patients with PC who had not received ADT served as the comparison group. Each study patient was individually tracked for a 3-year period to discriminate those who subsequently received a diagnosis of HZ. Of the total 1,726 sampled patients, the incidence rate of HZ per 100 person-years was 1.80 (95% CI: 1.41-2.25) during the 3-year follow-up period. In particular, incidence rates of HZ per 100 person-years were 2.36 (95% CI: 1.75-3.13) and 1.24 (95% CI: 0.81-1.81), respectively, for patients with PC who had and those who had not received ADT. Furthermore, Cox proportional hazard regressions showed that the adjusted hazard ratio for an HZ attack during the 3-year follow-up period for patients with PC who had received ADT was 1.88 (95% CI: 1.13-3.11) than those who had not received ADT. We concluded that patients with PC who had received ADT had an increased risk of HZ.

Candidate regulators of Early Leaf Development in Maize Perturb Hormone Signalling and Secondary Cell Wall Formation When Constitutively Expressed in Rice

All grass leaves are strap-shaped with a series of parallel veins running from base to tip, but the distance between each pair of veins, and the cell-types that develop between them, differs depending on whether the plant performs C₃ or C₄ photosynthesis. As part of a multinational effort to introduce C₄ traits into rice to boost crop yield, candidate regulators of C₄ leaf anatomy were previously identified through an analysis of maize leaf transcriptomes. Here we tested the potential of 60 of those candidate genes to alter leaf anatomy in rice. In each case, transgenic rice lines were generated in which the maize gene was constitutively expressed. Lines grouped into three phenotypic classes: (1) indistinguishable from wild-type; (2) aberrant shoot and/or root growth indicating possible perturbations to hormone homeostasis; and (3) altered secondary cell wall formation. One of the genes in class 3 defines a novel monocot-specific family. None of the genes were individually sufficient to induce C₄-like vein patterning or cell-type differentiation in rice. A better understanding of gene function in C₄ plants is now needed to inform more sophisticated engineering attempts to alter leaf anatomy in C₃ plants.

CRISPR-Cas9 and CRISPR-Cpf1 mediated targeting of a stomatal developmental gene EPFL9 in rice

CRISPR-Cas9/Cpf1 system with its unique gene targeting efficiency, could be an important tool for functional study of early developmental genes through the generation of successful knockout plants. The introduction and utilization of systems biology approaches have identified several genes that are involved in early development of a plant and with such knowledge a robust tool is required for the functional validation of putative candidate genes thus obtained. The development of the CRISPR-Cas9/Cpf1 genome editing system has provided a convenient tool for creating loss of function mutants for genes of interest. The present study utilized CRISPR/Cas9 and CRISPR-Cpf1 technology to knock out an early developmental gene EPFL9 (Epidermal Patterning Factor like-9, a positive regulator of stomatal development in Arabidopsis) orthologue in rice. Germ-line mutants that were generated showed edits that were carried forward into the T2 generation when Cas9-free homozygous mutants were obtained. The homozygous mutant plants showed more than an eightfold reduction in stomatal density on the abaxial leaf surface of the edited rice plants. Potential off-target analysis showed no significant off-target effects. This study also utilized the CRISPR-LbCpf1 (Lachnospiracae bacterium Cpf1) to target the same OsEPFL9 gene to test the activity of this class-2 CRISPR system in rice and found that Cpf1 is also capable of genome editing and edits get transmitted through generations with similar phenotypic changes seen with CRISPR-Cas9. This study demonstrates the application of CRISPR-Cas9/Cpf1 to precisely target genomic locations and develop transgene-free homozygous heritable gene edits and confirms that the loss of function analysis of the candidate genes emerging from different systems biology based approaches, could be performed, and therefore, this system adds value in the validation of gene function studies.

Sulfate-reducing bacteria slow intestinal transit in a bismuth-reversible fashion in mice

BACKGROUND

Hydrogen sulfide (H₂ S) serves as a mammalian cell-derived gaseous neurotransmitter. The intestines are exposed to a second source of this gas by sulfate-reducing bacteria (SRB). Bismuth subsalicylate binds H₂ S rendering it insoluble. The aim of this study was to test the hypothesis that SRB may slow intestinal transit in a bismuth-reversible fashion.

METHODS

Eighty mice were randomized to five groups consisting of Live SRB, Killed SRB, SRB+Bismuth, Bismuth, and Saline. Desulfovibrio vulgaris, a common strain of SRB, was administered by gavage at the dose of 1.0 × 10⁹ cells along with rhodamine, a fluorescent dye. Intestinal transit was measured 50 minutes after gavage by euthanizing the animals, removing the small intestine between the pyloric sphincter and the ileocecal valve and visualizing the distribution of rhodamine across the intestine using an imaging system (IVIS, Perkin-Elmer). Intestinal transit (n=50) was compared using geometric center (1=minimal movement, 100=maximal movement). H₂ S concentration (n=30) was also measured when small intestinal luminal content was allowed to generate this gas.

KEY RESULTS

The Live SRB group had slower intestinal transit as represented by a geometric center score of 40.2 ± 5.7 when compared to Saline: 73.6 ± 5.7, Killed SRB: 77.9 ± 6.9, SRB+Bismuth: 81.0 ± 2.0, and Bismuth: 73.3 ± 4.2 (P<.0001). Correspondingly, the Live SRB group had the highest luminal H₂ S concentration of 4181.0 ± 968.0 ppb compared to 0 ± 0 ppb for the SRB+Bismuth group (P<.0001).

CONCLUSIONS & INFERENCES

Live SRB slow intestinal transit in a bismuth-reversible fashion in mice. Our results demonstrate that intestinal transit is slowed by SRB and this effect could be abolished by H₂ S-binding bismuth.

[Outcome of treatment of Y chromosome AZFc microdeletion patients]

OBJECTIVE

To discuss the treatment options for patients with azoospermia factor (AZF) c microdeletion on Y chromosome.

METHODS

One hundred and eighty three patients, who were diagnosed as AZFc microdeletion on Y chromosome in Peking University Third Hospital, were recruited in our study. In order to get better treatment option for this kind of patients, we retrospectively analyzed their clinic data including the treatment process and pregnancy outcome and found out the characteristics of their semen.

RESULTS

Among the 183 patients, sperms can be found in ejaculated semen in 105 patients (57.4%, 105/183). One hundred and three patients (98.1%, 103/105) were diagnosed as severe or extremely severe oligospermia. Regular medication was given to 98 patients, 6 patients (6.1%, 6/98) of which got natural pregnancy. The other 99 patients who have sperms in their semen received intracytoplasmic sperm injection (ICSI), 68 patients (68.7%, 68/99) of which got pregnancy. Seventy eight patients were diagnosed as azoospermia among all the 183 patients. Forty nine patients received testicular sperm aspiration (TESA), and 21 patients choose to receive micro-TESE directly. Among the 49 patients with TESA, sperms were retrieved in 17 patients (34.7%, 17/49), and sperms were not retrieved in 32 patients (65.3%, 32/49), of which 12 patients (37.5%, 12/32) gave up treatment and 20 patients (62.5%, 20/32) choose micro-TESE. Among the 41 patients who choose to receive micro-TESE, operation has been done on 19 patients, of which 11 patients (57.9%, 11/19) got sperms. Among the 11 patients, TESA has been done on 6 patients before micro-TESE, of which 4 patients (66.6%, 4/6) got sperms. ICSI has already been done on 7 azoospermia AZFc microdeletion patients who underwent micro-TESE, of which 4 patients (57.1%, 4/7) get pregnancy.

CONCLUSION

AZFc microdeletion patients who had sperms were always diagnosed as severe or extremely severe oligospermia. ICSI was their first choice instead of drug therapy. For AZFc microdeletion patients who were diagnosed as azoospermia, TESA was one of their choices, however, the success rate is not high. Micro-TESE is still possible to get sperms even after the failure of TESA. Therefore, we may choose micro-TESE instead of TESA in some azoospermia patients in order to reduce surgical trauma on patients.

Overexpression of OsSAP16 Regulates Photosynthesis and the Expression of a Broad Range of Stress Response Genes in Rice (Oryza sativa L.)

This study set out to identify and characterize transcription factors regulating photosynthesis in rice. Screening populations of rice T-DNA activation lines led to the identification of a T-DNA mutant with an increase in intrinsic water use efficiency (iWUE) under well-watered conditions. Flanking sequence analysis showed that the T-DNA construct was located upstream of LOC_Os07g38240 (OsSAP16) encoding for a stress-associated protein (SAP). A second mutant identified with activation in the same gene exhibited the same phenotype; expression of OsSAP16 was shown to be enhanced in both lines. There were no differences in stomatal development or morphology in either of these mutants, although overexpression of OsSAP16 reduced stomatal conductance. This phenotype limited CO2 uptake and the rate of photosynthesis, which resulted in the accumulation of less biomass in the two mutants. Whole transcriptome analysis showed that overexpression of OsSAP16 led to global changes in gene expression consistent with the function of zinc-finger transcription factors. These results show that the gene is involved in modulating the response of rice to drought stress through regulation of the expression of a set of stress-associated genes.

Targeted Knockdown of GDCH in Rice Leads to a Photorespiratory-Deficient Phenotype Useful as a Building Block for C4 Rice

The glycine decarboxylase complex (GDC) plays a critical role in the photorespiratory C2 cycle of C3 species by recovering carbon following the oxygenation reaction of ribulose-1,5-bisphosphate carboxylase/oxygenase. Loss of GDC from mesophyll cells (MCs) is considered a key early step in the evolution of C4 photosynthesis. To assess the impact of preferentially reducing GDC in rice MCs, we decreased the abundance of OsGDCH (Os10g37180) using an artificial microRNA (amiRNA) driven by a promoter that preferentially drives expression in MCs. GDC H- and P-proteins were undetectable in leaves of gdch lines. Plants exhibited a photorespiratory-deficient phenotype with stunted growth, accelerated leaf senescence, reduced chlorophyll, soluble protein and sugars, and increased glycine accumulation in leaves. Gas exchange measurements indicated an impaired ability to regenerate ribulose 1,5-bisphosphate in photorespiratory conditions. In addition, MCs of gdch lines exhibited a significant reduction in chloroplast area and coverage of the cell wall when grown in air, traits that occur during the later stages of C4 evolution. The presence of these two traits important for C4 photosynthesis and the non-lethal, down-regulation of the photorespiratory C2 cycle positively contribute to efforts to produce a C4 rice prototype.

Effects of missense mutations in sortase A gene on enzyme activity in Streptococcus mutans

Background

Streptococcus mutans (S. mutans) is the major aetiological agent of dental caries, and the transpeptidase Sortase A (SrtA) plays a major role in cariogenicity. The T168G and G470A missense mutations in the srtA gene may be linked to caries susceptibility, as demonstrated in our previous studies. This study aimed to investigate the effects of these missense mutations of the srtA gene on SrtA enzyme activity in S. mutans.

Methods

The point mutated recombinant S.mutans T168G and G470A sortases were expressed in expression plasmid pET32a. S. mutans UA159 sortase coding gene srtA was used as the template for point mutation. Enzymatic activity was assessed by quantifying increases in the fluorescence intensity generated when a substrate Dabcyl-QALPNTGEE-Edans was cleaved by SrtA. The kinetic constants were calculated based on the curve fit for the Michaelis-Menten equation.

Results

SrtA_{△N40(UA159)} and the mutant enzymes, SrtA_△N40(D56E) and SrtA_{△N40(R157H)}, were expressed and purified. A kinetic analysis showed that the affinity of SrtA_△N40(D56E) and SrtA_{△N40(R157H)} remained approximately equal to the affinity of SrtA_{△N40(UA159)}, as determined by the Michaelis constant (K_m). However, the catalytic rate constant (k_cat) and catalytic efficiency (k_cat/K_m) of SrtA_△N40(D56E) were reduced compared with those of SrtA_{△N40(R157H)} and SrtA_{△N40(UA159)}, whereas the k_cat and k_cat/K_m values of SrtA_{△N40(R157H)} were slightly lower than those of SrtA_{△N40(UA159)}.

Conclusions

The findings of this study indicate that the T168G missense mutation of the srtA gene results in a significant reduction in enzymatic activity compared with S. mutans UA159, suggesting that the T168G missense mutation of the srtA gene may be related to low cariogenicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-016-0204-1) contains supplementary material, which is available to authorized users.

[Outcome of treatment of Y chromosome AZFc microdeletion patients]

OBJECTIVE

To discuss the treatment options for patients with azoospermia factor (AZF) c microdeletion on Y chromosome.

METHODS

One hundred and eighty three patients, who were diagnosed as AZFc microdeletion on Y chromosome in Peking University Third Hospital, were recruited in our study. In order to get better treatment option for this kind of patients, we retrospectively analyzed their clinic data including the treatment process and pregnancy outcome and found out the characteristics of their semen.

RESULTS

Among the 183 patients, sperms can be found in ejaculated semen in 105 patients (57.4%, 105/183). One hundred and three patients (98.1%, 103/105) were diagnosed as severe or extremely severe oligospermia. Regular medication was given to 98 patients, 6 patients (6.1%, 6/98) of which got natural pregnancy. The other 99 patients who have sperms in their semen received intracytoplasmic sperm injection (ICSI), 68 patients (68.7%, 68/99) of which got pregnancy. Seventy eight patients were diagnosed as azoospermia among all the 183 patients. Forty nine patients received testicular sperm aspiration (TESA), and 21 patients choose to receive micro-TESE directly. Among the 49 patients with TESA, sperms were retrieved in 17 patients (34.7%, 17/49), and sperms were not retrieved in 32 patients (65.3%, 32/49), of which 12 patients (37.5%, 12/32) gave up treatment and 20 patients (62.5%, 20/32) choose micro-TESE. Among the 41 patients who choose to receive micro-TESE, operation has been done on 19 patients, of which 11 patients (57.9%, 11/19) got sperms. Among the 11 patients, TESA has been done on 6 patients before micro-TESE, of which 4 patients (66.6%, 4/6) got sperms. ICSI has already been done on 7 azoospermia AZFc microdeletion patients who underwent micro-TESE, of which 4 patients (57.1%, 4/7) get pregnancy.

CONCLUSION

AZFc microdeletion patients who had sperms were always diagnosed as severe or extremely severe oligospermia. ICSI was their first choice instead of drug therapy. For AZFc microdeletion patients who were diagnosed as azoospermia, TESA was one of their choices, however, the success rate is not high. Micro-TESE is still possible to get sperms even after the failure of TESA. Therefore, we may choose micro-TESE instead of TESA in some azoospermia patients in order to reduce surgical trauma on patients.

No increased risk of coronary heart disease for patients receiving androgen deprivation therapy for prostate cancer in Chinese/Taiwanese men

The relationship between androgen deprivation therapy (ADT) and coronary heart disease (CHD) remains controversial. Furthermore, the majority of such studies focused on Caucasian populations, and there is still a paucity of studies among Asian populations. This population-based study aimed to investigate the relationship between ADT and CHD in an ethnic Chinese (i.e., Taiwanese) population. We used data sourced from the Taiwan 'Longitudinal Health Insurance Database'. This study included 1278 patients with prostate cancer in the study group and 1278 subjects without prostate cancer in the comparison group. Each patient was individually tracked for a 3-year period to identify those who had subsequently received a diagnosis of CHD. The results showed that the incidence rate of CHD during the 3-year follow-up period was 4.69 (95% CI: 2.99-5.48) per 100 person-years and 2.67 (95% CI: 2.15-3.27) per 100 person-years for the study and comparison cohort, respectively. The Cox proportional hazard regression showed that the hazard ratio for CHD during the 3-year follow-up period for prostate cancer patients was 1.65 (95% confidence interval (CI) = 1.25-2.16) compared with comparison subjects after adjusting for patients' geographic location, monthly income, urbanization level, hypertension, diabetes, hyperlipidemia, and stroke. However, we failed to find a significant difference in the adjusted hazard of CHD during the 3-year follow-up period between prostate cancer patients who did and those who did not receive ADT (hazard ratio = 1.12, 95% CI = 0.79-1.59). We concluded that prostate cancer but not ADT was significantly associated with CHD. In addition, a common cause of prostate cancer and coronary heart disease could exist.

Benign prostatic enlargement is not associated with diabetes: a population-based study

The association between diabetes and benign prostatic hyperplasia remains inconclusive. In this case-control study, we examined the association of diabetes with benign prostatic enlargement (BPE) using the Longitudinal Health Insurance Database 2000 in Taiwan. In total, 20 152 patients with BPE as cases and 20 152 age-matched patients without BPE were included as controls. Conditional logistic regression analyses were performed to calculate the odds ratio (OR) and corresponding 95% CI for having been previously diagnosed with diabetes between cases and controls. We found that of the 40 304 sampled patients, 9492 (23.6%) had a history of diabetes before the index date. This mean age for the sampled patients was 65.9 with a standard deviation of 12.0 years. A Chi-squared test revealed that there was a significant difference in the prevalence of prior diabetes between cases and controls (25.3% vs. 21.8%, p < 0.001). The conditional logistic regression found that the OR of prior diabetes for cases was 1.21 (95% CI = 1.15-1.27) compared with controls. However, after adjusting for geographic region, monthly income, urbanization level, hypertension, coronary heart disease (CHD), hyperlipidemia, tobacco use disorder, and obesity, the association between prior diabetes and BPE did not reach a statistically significant level (OR = 1.03, 95% CI = 0.98-1.08). In addition, it was noteworthy that hypertension (OR = 1.25, 95% CI = 1.20-1.31), CHD (OR = 1.40, 95% CI = 1.32-1.48), and hyperlipidemia (OR = 1.30, 95% CI = 1.24-1.36) were all significantly associated with BPE. We found that men with a diagnosis of diabetes were not significantly associated with BPE after adjusting for patient's sociodemographic characteristics and comorbidities.

Statin Use Is Associated with Bladder Pain Syndrome/Interstitial Cystitis: A Population-Based Case-Control Study

INTRODUCTION

Statin may induce epithelial dysfunction of the bladder urothelium. Epithelial dysfunction was proposed as one of the major potential etiologies for bladder pain syndrome/interstitial cystitis (BPS/IC). In this study, we examined the association between statin use and BPS/IC using a population-based study.

SUBJECTS AND METHODS

This case-control study used the Taiwan Longitudinal Health Insurance Database. In total, 815 female subjects with BPS/IC and 4075 randomly selected female controls were included. We used a conditional logistic regression to compute the odds ratio (OR) for having previously used statins between cases and controls.

RESULTS

A conditional logistic regression analysis showed that the OR of prior statin users for cases was 1.52 (95% confidence interval (CI): 1.19-1.94) compared to controls after adjusting for diabetes, hypertension, coronary heart disease, obesity, chronic pelvic pain, irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, depression, panic disorder, migraines, sicca syndrome, allergies, endometriosis, and asthma. Furthermore, adjusted ORs of regular and irregular statin use for cases were 1.58 (95% CI: 1.20-2.08) and 1.53 (95% CI: 1.02-2.31), respectively, compared to controls.

CONCLUSION

We concluded that there was an association between statin use and BPS/IC.

Dementia is associated with open-angle glaucoma: a population-based study

PURPOSE

Previous epidemiologic studies that focused on the association between open-angle glaucoma (OAG) and dementia showed inconsistent results. In the present study, we explored the association between OAG and dementia in an ethnic Chinese (i.e., Taiwanese) population using a population-based data set.

METHODS

We retrieved data on study subjects for this case-control study from the Longitudinal Health Insurance Database 2000. We identified 7770 patients who had a diagnosis of dementia as cases, and 7770 subjects matched in terms of sex and age, which were randomly extracted as controls. A conditional logistic regression conditioned on age group, sex, and index year was used to assess the association of dementia with previously diagnosed OAG among the sampled patients.

RESULTS

Of 15,540 patients, 1.70% had prior OAG, including 2.02% of the dementia group and 1.38% of the controls. After adjusting for patient socioeconomic characteristics and comorbid medical disorders, dementia patients were more likely to have had prior OAG than controls (odds ratio (OR): 1.44; 95% confidence interval (CI): 1.12-1.85; P<0.01). In addition, female dementia patients were more likely to have had prior OAG than controls (OR: 1.93; 95% CI: 1.35-2.77; P<0.001), whereas no statistical difference in prior OAG between male dementia patients and controls was found.

CONCLUSIONS

Female dementia patients were associated with a higher proportion of prior OAG than were the controls.

Impact of early childhood caries on oral health-related quality of life of preschool children

AIM

Child oral health-related quality of life (COHRQoL) has been assessed in developed areas; however, it remains unstudied in mainland China. Studies on COHRQoL would benefit a large number of children in China suffering from oral health problems such as dental caries. This study explored the relationship between COHRQoL and early childhood caries, adjusted by socioeconomic factors, in 3- to 4-year-old children in a region of southern China.

MATERIALS AND METHODS

In this study, 1062 children aged 3-4 years were recruited by cluster sampling and their oral health statuses were examined by a trained dentist. The Chinese version of the Early Childhood Oral Health Impact Scale (ECOHIS) and questions about the children's socioeconomic conditions were completed by the children's parents. A negative binomial regression analysis was used to assess the prevalence of early childhood caries among the children and its influence on COHRQoL.

RESULTS

The total ECOHIS scores of the returned scale sets ranged from 0 to 31, and their average scores was 3.1±5.1. The negative binomial analysis showed that the dmfs indices were significantly associated with the ECOHIS score and subscale scores (P<0.05). The multivariate adjusted model showed that a higher dmft index was associated with greater negative impact on COHRQoL (RR = 1.10; 95% CI = 1.07, 1.13; P < 0.05). However, demographic and socioeconomic factors were not associated with COHRQoL (P>0.05).

CONCLUSION

The severity of early childhood caries has a negative impact on the oral health-related quality of life of preschool children and their parents.

An unexpected route for otolaryngology bacterial contamination with a Venturi atomizer

BACKGROUND

The Venturi-principle atomizer is a commonly used device in otolaryngology practices. The purpose of this study is to evaluate the possible route of bacterial contamination from the nasal vestibule to the atomizer tip through the jet airflow created during the use of the Venturi atomizer.

METHODS

Thirty nostrils from 15 enrolled volunteers were tested. The aerosols generated by spraying sterilized saline into the nostrils were collected using a specially made aerosol-collecting nozzle cap. The collected samples were sent for bacterial culture, and nasal vestibular swab cultures were performed for comparison.

RESULTS

In the aerosol-exposed group, 18 out of 30 samples (60%) were positive for bacterial growth, confirming the bacterial contamination from the nasal vestibule to the atomizer tip through the reverse jet airflow. The bacteria species in 8 of the 18 positive samples were identical to those from the nasal swab culture results from the same nostril.

CONCLUSION

In ordinary otolaryngology practices, there are significant risks for bacterial contamination from the nasal vestibule to the tip of the Venturi atomizer even without direct contact. Clinicians must be more aware of this pattern of contamination, which has not been reported in the existing literature.

Factors associated with colonization of Streptococcus mutans in 8- to 32-month-old children: a cohort study

BACKGROUND

The factors involved in Streptococcus mutans colonization in young children are not clear. The aim of this study was to determine the factors associated with S. mutans colonization in 8- to 32-month-old children.

METHODS

A group of 225 caries-free 8-month-old children was recruited for the study. They were examined every six months until they were 32 months old to investigate their environmental factors, host factors and bacterial transmission factors. At baseline and during each examination, their teeth were checked for the presence of dental plaque and developmental defects of enamel, and S. mutans plaque status was assessed using a real-time PCR test.

RESULTS

Eight children (3.6%) showed S. mutans colonization by the age of 8 months. The percentages of colonization were 6.0% at 14 months, 16.2% at 20 months, 26.7% at 26 months, and 33.5% at 32 months. The results showed that females (p = 0.006), children with enamel hypoplasia (p = 0.024), children with low birth weights (p = 0.005), those who consume more sweets (p < 0.001), and those with a higher proportion of visible plaque (p = 0.020 and p = 0.041) were more likely to be colonized by S. mutans.

CONCLUSIONS

Streptococcus mutans colonization in young children was associated with gender, tooth enamel hypoplasia, low birth weight, frequent consumption of sweets and poor oral hygiene.

Dose effect of thiazolidinedione on cancer risk in type 2 diabetes mellitus patients: a six-year population-based cohort study

WHAT IS KNOWN AND OBJECTIVE

Prior studies found that thiazolidinediones (TZDs) might have tumour-suppressor activity mediated through cell-cycle arrest, induction of apoptosis and inhibition of cell invasion. The main objective of this study was to investigate the effects of TZDs on the risk of cancer among patients with type 2 diabetes mellitus (DM).

METHODS

Patients diagnosed with DM between 1 January 1998 and 31 December 2002 were identified from the Longitudinal Health Insurance Database (LHID) within the Taiwan National Health Insurance (NHI) programme. Using Cox regression models, we assessed the association between prescribed TZDs and cancer risk, TZDs' dose effect and the association between TZDs and specific cancer types. Hazard ratios (HR) were adjusted for potential confounders (age, gender, income, Charlson score index, metformin and insulin use).

RESULTS AND DISCUSSION

The adjusted HRs for those prescribed TZD were 0·74 (95% CI 0·43-1·26, P = 0·27), 0·39 (95% CI 0·33-0·45, P < 0·001) and 0·49 (95% CI 0·27-0·89, P = 0·02), respectively, relative to non-DM patients, DM patients prescribed other anti-DM drugs besides TZDs and DM patients not prescribed any anti-DM drugs. In addition, the effects of TZDs were shown to be significantly dose dependent (P for trend < 0·001). The risk of breast, brain, colorectal, ear-nose-throat, kidney, liver, lung, lymphatic, prostate, stomach, and uterus cancer was significantly lower in those prescribed TZDs.

WHAT IS NEW AND CONCLUSIONS

The results showed a decrease in cancer risk in diabetic patients using TZD, and the association was dose dependent.

Anomalous quantum efficiency for photoconduction and its power dependence in metal oxide semiconductor nanowires

The quantum efficiency and carrier lifetime that decide the photoconduction (PC) efficiencies in the metal oxide semiconductor nanowires (NWs) have been investigated. The experimental result surprisingly shows that the SnO2, TiO2, WO3, and ZnO NWs reveal extraordinary quantum efficiencies in common, which are over one to three orders of magnitude lower than the theoretical expectation. The surface depletion region (SDR)-controlled photoconductivity is proposed to explain the anomalous quantum efficiency and its power dependence. The inherent difference between the metal oxide nanostructures such as carrier lifetime, carrier concentration, and dielectric constant leading to the distinct PC performance and behavior are also discussed.

Effects of prolonged intensive training on the resting levels of salivary immunoglobulin A and cortisol in adolescent volleyball players

AIM

Concerns have been raised regarding the effects of prolonged intensive training on adolescent athletes. This study investigated the differences in mucosal immune functions and stress responses between intensively trained male adolescent volleyball players and age-matched sedentary controls.

METHODS

Twelve male volleyball players (16.5 [0.7] years of age) and sixteen healthy sedentary male volunteers (17.1 [0.6] years of age) participated in this study. Volleyball players were engaged in regular and year-round training. Unstimulated saliva samples were collected from volleyball players during the high-intensity training period and from the counterparts at the same timepoints after at least 18 hours of rest. Concentrations of salivary total protein, secretory immunoglobulin A (SIgA), cortisol, and lactoferrin were measured.

RESULTS

Results of this study revealed that the SIgA concentrations and the ratio of SIgA/total protein in volleyball players were significantly lower compared with those in sedentary controls. However, the salivary cortisol concentrations and the ratio of cortisol/total protein in volleyball players were markedly higher compared with those in sedentary controls. No significant difference was observed in lactoferrin levels between volleyball players and sedentary controls.

CONCLUSION

The findings of this study suggest that the prolonged intensive training may elicit a sustained stress and induce a suppressive effect on mucosal immunity in regularly and intensively trained adolescent athletes.

Randomized trial on fluorides and sealants for fissure caries prevention

To investigate the effectiveness of topical fluorides in preventing fissure caries, we conducted a randomized controlled trial with parallel groups. In total, 501 children (1,539 molars, 3,078 sites), mean age 9.1 years, who had at least one sound permanent first molar with deep fissures or fissures with signs of early caries were recruited. They were randomly allocated among four groups: (1) resin sealant, single placement; (2) 5% NaF varnish, semi-annual application; (3) 38% silver diamine fluoride (SDF) solution, annual application; and (4) placebo control. Follow-up examinations were conducted every 6 months by a masked examiner. After 24 months, 485 children (97%) were examined. Proportions of pit/fissure sites with dentin caries in the sealant, NaF, SDF, and control groups were 1.6%, 2.4%, 2.2%, and 4.6%, respectively. A multi-level logistic regression analysis accounting for the effects of data clustering and confounding factors showed that fissures in any of the three treatment groups had significantly lower risks of carious cavity development into dentin than did controls (p < 0.05). We concluded that placement of resin sealant, semi-annual application of NaF varnish, and annual application of SDF solution are all effective in preventing pit and fissure caries in permanent molars (ClinicalTrials.gov number CT01446107).

Genetic polymorphisms of the sortase A gene and early childhood caries in two-year-old children

OBJECTIVE

To explore and compare the genetic polymorphisms of the sortase A (srtA) gene found in Streptococcus mutans (S. mutans) infecting two-year-old children suffering early childhood caries to those found in caries-free children through molecular identification methods.

METHODS

Clinical S. mutans strains were isolated from the dental plaques of two-year-old children. Fifteen strains of S. mutans from the caries-active group and 15 strains of S. mutans from the caries-free group were collected. Genomic DNA was extracted from the S. mutans isolates. DNA fragments, including the srtA gene, were amplified by PCR. The PCR products were purified, sequenced and analyzed. A chi-square test and BioEdit software were used to analyze the sequencing results.

RESULTS

All 30 clinically isolated S. mutans strains had a 741 base pair (bp) srtA gene. There were no nucleotide sequence insertions or deletions observed in the srtA genes. Twenty mutations were identified in the srtA genes that taken from the 30 clinical strains. There were 10 silent point mutations at the 78, 99, 150, 165, 186, 222, 249, 261, 312, and 636bp positions. The other 10 mutations were point mutations resulting in a missense mutation at the 23, 34, 36, 47, 112, 114, 168, 176, 470, and 671bp positions. None of the positions were enzyme-activity sites of srt A. The missense mutation rates of the two groups did not exhibit statistically significant differences.

CONCLUSION

There were no genetic polymorphisms of the sortase A gene associated with early childhood caries in two-year-old children.

Electrical and optical properties of NiO composite films by radio frequency magnetron sputtering

The 100-nm NiO-Ag composite films with Ag content of 0 to 24.4 at.% are deposited on glass substrates. It is found that an ultra high electric resistivity (rho) value is obtained and cannot be detected by four point probe measurement when the Ag content is less than 3.4 at.%. The rho value is reduced significantly to 29.0 Omega-cm as Ag content is increased to 4.2 at.%, and it decreases greatly to 0.009 Omega-cm as the content of Ag is further increased to 24.4 at.%. The NiO-Ag composite film with Ag content of 4.2 at.% shows p-type conduction. However, it becomes n-type when the Ag content increases to 9.3 at.%, which results from the Ag atoms segregated at grain boundary of NiO when the excess Ag atoms are added into NiO films. On the other hand, the transmittance of the NiO-Ag films drops continuously from 96.3% to 31.6% as the Ag content increases from 0 to 24.4%.

Clinical and socio-demographic factors influencing the oral health-related quality of life of Chinese elders

OBJECTIVES

The objective of this study was to explore the clinical and socio-demographic factors influencing oral health-related quality of life (OHRQoL) of the Chinese elderly.

METHODS

Two urban districts in Binzhou, Shandong Province, Eastern China were selected and 300 elders aged 60-80 years were recruited. The study subjects completed a structured questionnaire in an interview and underwent a clinical examination. The questionnaire included questions on socio-economic information and a Putonghua version of the General Oral Health Assessment Index (GOHAI) which had been validated for use in Chinese elders to evaluate their OHRQoL. Clinical examination was performed using the criteria recommended by the World Health Organization. Tooth status, periodontal health status, loss of attachment (LOA), and number of occluding tooth pairs were recorded. Duplicate examinations were conducted on 10% of the subjects.

RESULTS

The mean GOHAI score of the subjects was 46.0 (SD 8.5). Result of an ANCOVA showed that subjects who were older, had no root caries, had no tooth with LOA > or = 6mm, or had more occluding pairs had higher GOHAI scores indicating better OHRQoL.

CONCLUSION

The OHRQoL of the study elders was fair and was influenced by age and a number of clinical factors. With limited resources and dental manpower in China, higher priority should be given to the elders who are relatively younger, who have or are at high risk of developing root caries and advanced periodontal diseases, and who have few occluding tooth pairs.

Pharmacokinetics of ketamine in plasma and milk of mature Holstein cows

The purpose of this study was to evaluate the pharmacokinetics of ketamine in mature Holstein cows following administration of a single intravenous (i.v.) dose. Plasma and milk concentrations were determined using a high-performance liquid chromatography assay. Pharmacokinetic parameters were estimated using a noncompartmental method. Following i.v. administration, plasma T(max) was 0.083 h and plasma C(max) was 18,135 ± 22,720 ng/mL. Plasma AUC was 4484 ± 1,398 ng·h/mL. Plasma t(½β) was 1.80 ± 0.50 h and mean residence time was 0.794 ± 0.318 h with total body clearance of 1.29 ± 0.70 L/h/kg. The mean plasma steady-state volume of distribution was calculated as 0.990 ± 0.530 L/kg and volume of distribution based on area was calculated as 3.23 ± 1.51 L/kg. The last measurable time for ketamine detection in plasma was 8.0 h with a mean concentration of 24.9 ± 11.8 ng/mL. Milk T(max) was detected at 0.67 ± 0.26 h with C(max) of 2495 ± 904 ng/mL. Milk AUC till the last time was 6593 ± 2617 ng·h/mL with mean AUC milk to AUC plasma ratio of 1.99 ± 2.15. The last measurable time that ketamine was detected in milk was 44 ± 10.0 h with a mean concentration of 16.0 ± 9.0 ng/mL.