Soil, Plant, and Microorganism Interactions Drive Secondary Succession in Alpine Grassland Restoration

Plant secondary succession has been explored extensively in restoring degraded grasslands in semiarid or dry environments. However, the dynamics of soil microbial communities and their interactions with plant succession following restoration efforts remain understudied, particularly in alpine ecosystems. This study investigates the interplay between soil properties, plant communities, and microbial populations across a chronosequence of grassland restoration on the Qinghai-Tibet Plateau in China. We examined five succession stages representing artificial grasslands of varying recovery durations from 0 to 19. We characterized soil microbial compositions using high-throughput sequencing, enzymatic activity assessments, and biomass analyses. Our findings reveal distinct plant and microbial secondary succession patterns, marked by increased soil organic carbon, total phosphorus, and NH4+-N contents. Soil microbial biomass, enzymatic activities, and microbial community diversity increased as recovery time progressed, attributed to increased plant aboveground biomass, cover, and diversity. The observed patterns in biomass and diversity dynamics of plant, bacterial, and fungal communities suggest parallel plant and fungal succession occurrences. Indicators of bacterial and fungal communities, including biomass, enzymatic activities, and community composition, exhibited sensitivity to variations in plant biomass and diversity. Fungal succession, in particular, exhibited susceptibility to changes in the soil C: N ratio. Our results underscore the significant roles of plant biomass, cover, and diversity in shaping microbial community composition attributed to vegetation-induced alterations in soil nutrients and soil microclimates. This study contributes valuable insights into the intricate relationships driving secondary succession in alpine grassland restoration.

Insights into the mechanism involved by electric double layer on phosphate removal of metal-bearing environmental remediation agent: Taking tricalcium aluminate as representative

Metal-bearing materials are known to be desirable environmental captures for phosphate removal, yet few studies focus on understanding the reaction process, especially formed a special phenomenon, i.e., electric double layer (EDL), which might influence the phosphate removal. To fill in this gap, we fabricated metal-bearing tricalcium aluminate (C₃A, Ca₃Al₂O₆) as representative, to remove phosphate and unveil the impact by electric double layer (EDL). Specifically, a preeminent removal capacity of 142.2 mg·g^-1 was achieved at the initial phosphate concentration below 300 mg·L^-1. Following thorough the characterizations, the process was that the released Ca²⁺ or Al³⁺ of C₃A formed positive charged stern layer attracted phosphate to generate Ca or Al-precipitation. At high phosphate concentration (>300 mg·L^-1), C₃A exhibited inferior removal capability for phosphate (<45 mg·g^-1), due to the aggregation of C₃A particles with low water permeability under the EDL effect, obstructing Ca²⁺ and Al³⁺ to release for phosphate removal. In addition, the feasibility application of C₃A was evaluated based on response surface methodology (RSM), highlighting its prospective phosphate treatment. This work not only provides a theoretical guidance for the application of C₃A to remove phosphate, but also deepens the understand of phosphate removal mechanism by metal-bearing materials, shedding light on environmental remediation.

[Clinical features of 19 patients with SIL-TAL1-positive T-cell acute lymphoblastic leukemia]

Objective: To assess the clinical characteristics and prognosis of patients with SIL-TAL1-positive T-cell acute lymphoblastic leukemia (T-ALL) . Methods: The clinical data of 19 SIL-TAL1-positive T-ALL patients admitted to the First Affiliated Hospital of Soochow University between January 2014 and February 2022 were retrospectively computed and contrasted with SIL-TAL1-negative T-ALL patients. Results: The median age of the 19 SIL-TAL1-positive T-ALL patients was 15 (7 to 41 years) , including 16 males (84.2%) . SIL-TAL1-positive T-ALL patients had younger age, higher WBC, and hemoglobin compared with SIL-TAL1-negative T-ALL patients. There was no discrepancy in gender distribution, PLT, chromosome abnormality distribution, immunophenotyping, and complete remission (CR) rate. The 3-year overall survival (OS) was 60.9% and 74.4%, respectively (HR=2.070, P=0.071) . The 3-year relapse-free survival (RFS) was 49.2% and 70.6%, respectively (HR=2.275, P=0.040) . The 3-year RFS rate of SIL-TAL1-positive T-ALL patients was considerably lower than SIL-TAL1-negative T-ALL patients. Conclusion: SIL-TAL1-positive T-ALL patients were connected to younger age, higher WBC, higher HGB, and poor outcome.

Engineering 3D graphene-like carbon-assembled layered double oxide for efficient microplastic removal in a wide pH range

Microplastics (MPs) elimination is becoming an intractable environmental issue due to their nonbiodegradable nature and wide spreading，especially in the case of wastewater containing acid or alkaline effluent. To target the dilemma, this work rationally engineered a robust three-dimensional graphene-like carbon assembled layered double oxide material (defined as G@LDO) from hierarchical organic LDH (i.e., 3D OLDH) via a "precursor-calcination" strategy. In virtue of the mutually protection effect of graphene-like carbon (G) and LDO, the engineered G@LDO featured the preeminent acid and base resistance for polystyrene (PS, as representative of MPs) removal. Especially and importantly, the removal efficiency of PS was ≥ 80% at pH= 3-11, even nearly 60% PS was removed at pH= 1 and 13. The maximum adsorption ability of G@LDO for PS was estimated to be 209.39 mg/g by a Langmuir isotherm model, much superior to that of pure G, LDO, and 2D G@LDO. Furthermore, the removal pathway was analyzed by kinetic together with thermodynamic study, revealing that the PS removal on G@LDO was an exothermic reaction controlled by chemisorption. By systematical characterization and DFT calculation, the removal mechanism of PS was revealed to be hydrogen bond and complexation associated with LDH recovered from LDO and π-π conjunction from G. Notably, the existence of sulfure (S) in the carbon network was also identified as significant component in PS removal via p-π interaction. Overall, this work not only provides a effective candidate for microplastics removal in a wide applicable scope (especially acid/alkaline effluent), shedding light on environmental remediation, but also opens a new anvenue for the disposal of LDHs adsorbed organic in a high value-added manner.

The Joint Toxicity of Organic Three-dimensional Layered Double Hydroxide and Methyl Orange to Green Algae Chlorella Vulgaris

Organic modified layered double hydroxides (O-LDHs), known as attractive adsorbents for organic pollutants, may pose severe toxicity to the aquatic organisms during their large-scale application. However, little information is available on the toxicity of O-LDHs and the joint toxicity with the coexisted organic pollutants. Herein, we employed organic three-dimensional layered double hydroxide (O3D-LDH) and methyl orange (MO) as representative to investigate the toxicity mechanisms of single substance and its binary mixture on green algae Chlorella vulgaris. Results showed that O3D-LDH and MO presented concentration-dependent toxicity, the binary mixture showed additive effect after exposed to low O3D-LDH concentration (≤ 50 mg/L), but antagonism was observed for the other. It revealed that the agglomeration of O3D-LDH and microalgae influenced chlorophyll content, eventually inhibiting the growth of algae. Overall, this toxicity investigation was critical for understanding the environmental risk of organic LDHs to provide theorical guidance for their practical application in the water purification.

High-efficiency water purification for methyl orange and lead(II) by eco-friendly magnetic sulfur-doped graphene-like carbon-supported layered double oxide

Traditional disposal techniques for the spent layered adsorbents after capturing organics suffer from intractable obstacles, such as resource waste and secondary pollution. To address this diploma, we here developed the "resource-utilization" strategy, i.e., converting the organic layered double hydroxide (as representative) to magnetic sulfur (S)-doped graphene-like carbon-supported layered double oxide (MG/S-LDO) to be reutilized in water purification. The as-prepared MG/S-LDO exhibited outstanding remediation ability toward methyl orange (MO) and lead(II), with the adsorption capacity of 1456 and 656 mg g^-1, respectively. Specifically, the residue concentration of Pb²⁺ was reduced to 0.15 mg L^-1 within 1 h, which met the discharge limit of the secondary industrial wastewater. MG/S-LDO could also maintain the preeminent adsorption capability under various interferences (such as wide pH and co-existing ions), even in the authentic water matrices. The removal mechanisms were systematically investigated to unveil that MO removal was dominated by metal-complexation, "memory effect", and π-π electron donor-acceptor (EDA). While for Pb²⁺ removal, besides the released OH^- from LDO as precipitate agent, the vacancy defect resulting from the S doping played a crucial role in electron interaction between Pb²⁺ and S-doped graphene. Additionally, the MG/S-LDO was further confirmed as an eco-friendly adsorbent with excellent reusability via the acute toxicity tests using green algae and multiple cycle experiments. This work provides a novel resource-utilization strategy for organic layered wastes to construct the functional eco-friendly materials in wastewater purification realm.

Heavy Grazing Altered the Biodiversity–Productivity Relationship of Alpine Grasslands in Lhasa River Valley, Tibet

Grazing is a crucial anthropogenic disturbance on grasslands. However, it is unknown how livestock grazing affects the relationship between biodiversity and productivity of alpine grasslands in Tibet. We carried out a grazing-manipulated experiment from 2016 to 2019 with grazing intensity levels of null (control, grazing exclusion, C.K.), moderate grazing [1.65 standardized sheep unit (SSU) per hectare, M.G.], and heavy grazing (2.47 SSU per hectare, H.G.) on a typical alpine grassland in the Lhasa River Basin, central Tibet. We measured aboveground biomass (AGB), species assembly (alpha and beta diversity indices), and soil nutrients’ availability. The results showed that grazing differently affected plant community in different treatments. Notably, the total dissimilarity value between C.K. and H.G. is 0.334. Grazing decreased the Shannon–Wiener index, increased the Berger–Parker index from 2016 to 2018 significantly, and decreased AGB and total soil nitrogen (STN) significantly. Our results also showed that the grazing affected the relationship between AGB and diversity indices and soil nutrients, including soil organic carbon (SOC) and total soil phosphorus (STP). Specifically, AGB decreased with increasing SOC and STP in all treatments, and heavy grazing changed the positive relationships between AGB, STP, and Shannon–Wiener index to negative correlations significantly compared with grazing exclusion. There was a significant negative correlation between Berger–Parker and Shannon–Wiener indices under each treatment. The general linear models showed that H.G. altered the relationship between diversity and productivity of grassland in central Tibet, and AGB and Shannon–Wiener index positively correlated in C.K. but negatively correlated in H.G. Our study suggests that H.G. caused a negative relationship between plant diversity and productivity. Therefore, sustainable grazing management calls for a need of better understanding the relationship between biodiversity and productivity of alpine grassland in central Tibet.

The tetracyclines removal by MgAl layered double oxide in the presence of phosphate or nitrate: Behaviors and mechanism exploration

Pollution of tetracyclines (TCs) in swine wastewater has been a critical concern worldwide. Notably, multiple anions (e.g. PO₄^3-, NO₃^-) coexist in the actual environments, which could significantly influence the TCs removal. In the current study, MgAl layered double oxide (MgAl-LDO) was adopted for investigating the TC removal performance with/without PO₄^3- or NO₃^-. In all systems, the adsorption performance exhibited two different approaches between low and high TC concentrations. In the single system, pseudo-second-order and the Freundlich model fitted well to the equilibrium adsorption data when TC concentration was below 125 mg·L^-1, while the pseudo-first-order and the linear model could describe the removal process at high TC concentration (>125 mg·L^-1). The maximum adsorption capacity was 83.56 mg·g^-1. In the co-existing system, the adsorption capacity was slightly enhanced when TC concentration below 150 mg·L^-1 however was inhibited at high concentration (>150 mg·L^-1). Combined with the characterization analyses, the interaction mechanism at low concentration was primarily surface adsorption on reconstructed LDH from LDO in the TC-alone system. It is worth mention that both PO₄^3- and NO₃^- facilitated the formation of LDH via rehydration of LDO which enhanced surface adsorption in the co-existing system. At high TC concentration, the formation of tetracycline-metal complexes played a dominant role in TC removal in the single system, whereas diminished complexation in the binary system led to the decreased TC removal. This study provides a theoretical and practical guidance for MgAl-LDO on the efficient remediation of actual tetracyclines wastewater.

[Effects of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children]

Objective: To explore the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Methods: From October to November 2017, 27 987 children aged 3 to 6 years old from 109 kindergartens in 11 cities of Hubei, Anhui and Jiangsu Provinces were selected by using the cluster sampling method. A total of 27 200 valid questionnaires which were completed by subjects' parents were collected. The emotional and behavioral problems of preschool children were collected by "strengths and difficulties questionnaire" and the parental rearing patterns were evaluated by the "Parental Behavior Scale". The differences in emotional and behavioral abnormality rates of preschool children with different characteristics were analyzed; with emotional and behavioral problems as dependent variables and parental support/participation and compulsion/hostility as independent variables, the multivariate logistic regression model was used to analyze the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Results: The age of children was (4.35±0.96) years old, and 51.4% of children were 13 975 males. There were 24 634 (90.6%) urban children and 17 916 (65.9%) only children. Both parents with strong support/participation accounted for 14.9%, and those with poor support/participation accounted for 11.9%; both parents with strong compulsion/hostility accounted for 15.2%, and those with low compulsion/hostility accounted for 11.3%. The rates of emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior of preschool children were 9.5%, 9.5%, 18.2%, 24.5%, 11.2%, and 10.2%, respectively. The multivariate logistic regression model analysis showed that after adjusting for gender, only child, living area, family economic status, mother's age and education level, father's education level, and other factors, compared with fathers/mothers with strong support/participation and low compulsion/hostility and parents with strong support/participation and low compulsion/hostility, preschool children who had fathers/mothers with poor support/participation and strong compulsion/hostility or parents with poor support/participation and strong compulsion/hostility were more likely to have emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior (P<0.05). Conclusions: Parental rearing patterns and their consistency are related to the emotional and behavioral problems of preschool children.

Novel Two-Dimensional Magnetic Titanium Carbide for Methylene Blue Removal over a Wide pH Range: Insight into Removal Performance and Mechanism

Two-dimensional (2D) layer-structured titanium carbide MXenes (e.g., 2D Ti₃C₂ MXene) have received tremendous attention owing to their excellent properties and unique 2D planar topology. Nevertheless, there are still several challenges to be addressed for well dispersibility and easy separation from a heterogeneous system, hindering the practical applications. Herein, 2D Ti₃C₂ MXene, as the most typical member of 2D MXenes, is functionalized with magnetic Fe₃O₄ nanoparticles via an in situ growth approach (designated as MXene@Fe₃O₄), which exhibits the intriguing phenomenon on methylene blue (MB) adsorption in the environmental remediation realm. The maximum adsorption capacity of the MXene@Fe₃O₄ composites for MB is calculated to be 11.68 mg·g^-1 by a Langmuir isotherm model. A thermodynamic study of the adsorption demonstrates that the reaction process is exothermic and entropy-driven. Attractively, the removal process is a pH-independent process, and the optimal MB adsorption capacity is achieved at pH = 3 or 11, which is ascribed to electrostatic interactions and the hydrogen bond effect. X-ray diffraction, Fourier transform spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculation results reveal that the adsorption process is based on a combination of Ti-OH···N bonding, electrostatic attraction, and reductivity. Furthermore, multiple cycle runs demonstrate an excellent stability and reusability of MXene@Fe₃O₄ composites. This study provides a promising approach for the alternative removal of MB and broadens the potential application of 2D MXene for the treatment of practical acidic or alkaline wastewater.

The enhancement roles of sulfate on the adsorption of sodium dodecylsulfate by calcium-based layered double hydroxide: microstructure and thermal behaviors

As a commonly used surfactant, sodium dodecyl sulfate (SDS) usually coexists with inorganic anions in the industrial wastewater. These anions have a significant influence on SDS removal, indirectly threatening the environment. It is important to understand the relationship between the adsorption of SDS and inorganic anions. In this study, calcium-based layered double hydroxide (CaAl-LDH-Cl) as an efficient adsorbent was synthesized for investigating the effect of SO₄^2- on SDS removal. The SDS adsorption capacities were enhanced to 3.21 and 4.21 mmol g^-1 in the presence of SO₄^2- with low/high SDS concentration, respectively. The phenomenon and mechanism were confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM). Anionic exchange played a dominant role in the adsorption of SDS onto CaAl-LDH-Cl at DS^-/SO₄^2- < 2, while both anion exchange and precipitation occurred when DS^-/SO₄^2- exceeded 2. Moreover, the thermal analysis (TG-DTA) was employed to further reveal the interaction mechanism. The results showed the highest total mass loss and the lowest loss temperature of interlayer water in the sulfate coexist system, confirming the enhancement of SDS adsorption amount in the presence of SO₄^2-.

Association between the resistin gene-420 C>G polymorphism and obesity: an updated meta-analysis

OBJECTIVE

The aim of this study was to assess the relationship of the resistin gene (RETN)-420 C>G polymorphism and obesity susceptibility by conducting an updated meta-analysis.

MATERIALS AND METHODS

The electronic databases including PubMed, Medline, Embase, China National Knowledge Infrastructure, Chinese Wanfang Database, and Chinese VIP database were searched for relevant studies published before December 2013. The fixed effect model or random effects model was used based on the heterogeneity test results. The sensitivity analysis was performed in the allelic model and the dominant genetic model, respectively. Publication bias was assessed via funnel plot. The meta-analysis was performed using the software of RevMan 5.2.

RESULTS

Data were obtained from 10 included studies, involving 5,069 cases and 6,673 controls. The overall odds ratios (ORs) with its 95% confidence interval (CI) showed no association between RETN-420 C>G polymorphism and obesity in the allelic model (p = 0.09; OR = 1.10; 95% CI = 0.991.24), the dominant model (p = 0.09; OR = 1.16; 95% CI = 0.98-1.36), and the recessive model (p = 0.71; OR = 1.02; 95% CI = 0.90-1.16). Sensitivity analysis showed statistical differences of association analysis within the allelic model (p = 0.04; OR = 1.14; 95% CI = 1.01-1.28) and the dominant genetic model (p = 0.04; OR = 1.21; 95% CI = 1.01-1.45), when 1 study was omitted. No publication bias was observed.

CONCLUSIONS

The RETN-420 C>G polymorphism may be related to obesity with G allele as a risk factor.

Clinic research on the treatment for humeral shaft fracture with minimal invasive plate osteosynthesis: a retrospective study of 128 cases

INTRODUCTION

Minimal invasive plate osteosynthesis (MIPO) is one of the most important techniques in the treatment for humeral shaft fractures. This study was performed to evaluate the efficacy of MIPO technique for the treatment for humeral shaft fractures.

MATERIALS AND METHODS

We retrospectively evaluated 128 cases with humeral shaft fractures that were treated with MIPO technique from March 2005 to August 2008. All the patients were followed up by routine radiological imaging and clinical examinations. Constant-Murley score and HSS elbow joint score were used to evaluate the treatment outcome.

RESULTS

The average duration of the surgery was 60 min (range 40-95 min) without blood transfusion. All fractures healed without infection. All cases recovered carrying angle except four cases with 10°-15° cubitus varus. After the average follow-up of 23 (13-38) months, satisfactory function was achieved according to Constant-Murley score and HSS elbow joint score. Constant-Murley score was 80 on average (range 68-91). According to HSS elbow joint score, there were 123 cases of excellent clinical outcome and five cases of effective outcome.

CONCLUSION

It seems to be a safe and effective method for managing humeral shaft fractures with MIPO technique.

MicroRNAs in avian influenza virus H9N2-infected and non-infected chicken embryo fibroblasts

There is limited information about microRNAs (miR-NAs) in H9N2 subtype influenza virus-infected chicken cells or tissues. In this study, 10,487,469 and 13,119,795 reads were obtained from in-fected and non-infected chicken embryo fibroblasts, respectively. Seven hundred and thirty-six and 1004 miRNAs, including mature miRNAs and precursors, were obtained from the infected and non-infected fibro-blasts, respectively. Of those miRNAs, 48 were expressed differently between the groups: 37 had a low expression level in the infected chick-en embryo fibroblast, and the remaining 11 had a higher expression level. Every miRNA was predicted to target immune response-related genes. It has been found that some of the miRNAs, such as gga-miR-146c, gga-miR-181a, gga-miR-181b, gga-miR-30b, gga-miR-30c, gga-miR-30e, and gga-miR-455, are expressed differently in other types of influenza-infected chicken cells or tissues.

Psychrophilic fungi from the world's roof

During a survey of cold-adapted fungi in alpine glaciers on the Qinghai-Tibet Plateau, 1 428 fungal isolates were obtained of which 150 species were preliminary identified. Phoma sclerotioides and Pseudogymnoascus pannorum were the most dominant species. Psychrotolerant species in Helotiales (Leotiomycetes, Ascomycota) were studied in more detail as they represented the most commonly encountered group during this investigation. Two phylogenetic trees were constructed based on the partial large subunit nrDNA (LSU) to infer the taxonomic placements of these strains. Our strains nested in two well-supported major clades, which represented Tetracladium and a previously unknown lineage. The unknown lineage is distant to any other currently known genera in Helotiales. Psychrophila gen. nov. was therefore established to accommodate these strains which are characterised by globose or subglobose conidia formed from phialides on short or reduced conidiophores. Our analysis also showed that an LSU-based phylogeny is insufficient in differentiating strains at species level. Additional analyses using combined sequences of ITS+TEF1+TUB regions were employed to further investigate the phylogenetic relationships of these strains. Together with the recognisable morphological distinctions, six new species (i.e. P. antarctica, P. lutea, P. olivacea, T. ellipsoideum, T. globosum and T. psychrophilum) were described. Our preliminary investigation indicates a high diversity of cold-adapted species in nature, and many of them may represent unknown species.

Clinicopathological characteristics and computed tomography features of mucinous gastric carcinoma

This study investigated the clinicopathological characteristics of mucinous gastric carcinoma (MGC) and assessed whether multidetector-row computed tomography (MDCT) could differentiate MGC from non-mucinous gastric carcinoma (NGC). Clinicopathological data from 542 patients with gastric carcinoma (23 MGC, 519 NGC), who underwent pre-operative MDCT examination and curative or palliative gastrectomy, were analysed. Only seven of the 23 patients with MGC were correctly diagnosed pre-operatively by endoscopic biopsy. The MGC patients had larger tumours, a higher frequency of lymph node metastases, were more likely to have tumours of tumour, node, metastasis stages III and IV, and were less likely to have a curative resection than NGC patients. In addition, five MGC patients had calcifications in the thickened gastric wall. In conclusion, MGC is rare and is detected mostly at an advanced stage. The diagnostic sensitivity of MGC by endoscopic biopsy was relatively low, whereas MDCT was helpful in distinguishing MGC from NGC.

Size of the largest lymph node visualized on multi-detector-row computed tomography (MDCT) is useful in predicting metastatic lymph node status of gastric cancer

This study was designed to investigate whether the size of the largest lymph node (long-axis diameter [LAD] and short-axis diameter [SAD]) visualized using multi-detector-row computed tomography (MDCT) was useful for predicting the metastatic lymph node (MLN) status of gastric cancer. A retrospective analysis of 305 gastric cancer patients who underwent pre-operative MDCT was performed, followed by a prospective study in 61 gastric cancer patients to determine the diagnostic effectiveness of LAD and SAD. In the retrospective study, the accuracy of LAD and SAD for predicting the MLN status of gastric cancer was 51.1% and 45.9%, respectively. In the prospective study, the accuracy of LAD and SAD measurement and the traditional MDCT method of counting MLNs was 52.5%, 49.2% and 57.4%, respectively; the differences were not significant. In conclusion, the size of the largest lymph node in terms of LAD and SAD visualized on MDCT was useful for predicting the MLN status of gastric cancer, with accuracy comparable to the traditional MDCT method of counting the total number of MLNs detected.

Post-operative complications of gastric cancer surgery: female gender at high risk

We applied physiological and operative severity score for the enumeration of morbidity and mortality (POSSUM) to evaluate overall surgical outcome and investigated the role of gender for early post-operative complications in gastric cancer surgery. The data from a total of 357 patients of gastric cancer were analysed by univariate and multivariate analysis. Post-operative complications were recorded according to definition of POSSUM. Post-operative complications of male and female patients were compared separately. The observed to estimated morbidity ratio (O:E) was 1.01. Among the pre-operative variables, patient gender was one of the independent risk factors for a higher rate of post-operative complications (risk ratio 1.777, P = 0.024). Post-operative complication was significantly higher in female patients. Similarly, post-operative length of stay was significantly longer and more severe complications were observed in female patients (P = 0.03). In conclusion, POSSUM system is a valid algorithm for risk-adjusted surgical audit. We conclude that a patient's gender influences the early post-operative complications after gastric cancer surgery. A detailed understanding on disparity of early post-operative complications between men and women may provide valuable information to improve surgical outcome of gastric cancer. However, results of this study need further confirmation by a prospective study involving a larger cohort.

Breast milk levels of zinc and omega-6 polyunsaturated fatty acids and growth of healthy Chinese infants

AIM

To examine the concentrations of zinc and omega-6 polyunsaturated fatty acids (omega-6 PUFAs) in breast milk, the impact of zinc on omega-6 PUFA metabolism, and the growth rate of infants.

METHODS

Forty-one mother-term infant pairs from a rural area of northern Beijing, China, who were 1 month (n = 18, group I) and 3 months (n = 23, group II) old and exclusively breastfed, were studied. The dietary records and the concentrations of zinc and omega-6 PUFAs in the milk of lactating women and the increase in weight and length of their infants during 1 and 3 postnatal months were analysed.

RESULTS

The dietary intakes of mothers in the two groups were the same, i.e. high in carbohydrate and low in fat, protein and energy. The maternal zinc intake was 7.5mg/d and thus reached only 34.6% of the current Recommended Nutrient Intake (RNI). The levels of zinc and arachidonic acid (AA, C20:4 omega-6) in the milk of group I were significantly higher than those in group II. Furthermore, significant positive correlations were found between the concentrations of zinc and AA in the breast milk and between the level of milk AA and weight gain.

CONCLUSION

Zinc may be a co-factor and essential for essential fatty acids (EFA) metabolism. Thus suboptimal zinc intake may cause EFA imbalance. Further studies of Chinese rural mother-infant pairs are necessary to determine whether zinc supplementation should be recommended when lactation exceeds 3 months.

Diet and Gene Expression: Delta-5 and Delta-6 Desaturases in Healthy Chinese and European Subjects

AIM

To compare the composition of fatty acids (FAs) in diet, and the expression of delta-6 desaturase (D6D) and delta-5 desaturase (D5D) genes in peripheral blood mononuclear cells (PBMCs) between Chinese and Europeans.

METHODS

Three-day dietary records from 20 subjects from Beijing, China (n = 10) and Kent, UK (n = 10) were analysed. Expression of PBMC D6D and D5D genes of the subjects was determined using RT-PCR.

RESULTS

The dietary intake of Chinese subjects contained less saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs), but more essential fatty acids (EFAs) than that of Europeans. Levels of expression of PBMC D6D and D5D genes of Chinese subjects were significantly lower than those of Europeans. A significant positive correlation was found between dietary intake of total SFAs and total MUFAs and expression of PBMC D6D and D5D genes, but a significant negative correlation between dietary intake of linoleic acid (LA) and alpha-linolenic acid (LNA) and the expression of PBMC D6D and D5D genes.

CONCLUSION

Intake of high SFAs and MUFAs appears to increase expression of PBMC D6D and D5D genes, whilst high EFAs intake appears to decrease expression of PBMC D6D and D5D genes. A follow-up study of the expression of D6D and D5D genes in Chinese who live in European countries with high SFA and MUFA diets would be of interest.

Brn-3a is required for the generation of proprioceptors in the mesencephalic trigeminal tract nucleus

The distribution of motor and proprioceptive neurons was investigated in the trigeminal nervous system of wild-type and Brn-3a knockout mice at embryonic day 18.5 and postnatal day 0. We found that the trigeminal motor nucleus (Mo5) contained abundant motoneurons in wild-type (mean number +/- SD per section = 128 +/- 22, range = 93-167) and knockout (mean number +/- SD per section = 121 +/- 23, range = 75-158) mice and that the cell size of Mo5 neurons was similar between these mice (wild-type, mean +/- SD = 165 +/- 59 microm2, range = 65-326 microm2; knockout, mean +/- SD = 167 +/- 59 microm2, range = 71-327 microm2). Mo5 neurons were immunoreactive for calcitonin gene-related peptide and such immunoreactive neurons were abundant in both wild-type and mutant mice. In the mesencephalic tract nucleus (Mes5) of wild-type mice, many proprioceptors (mean number +/- SD per section = 56 +/- 19, range = 27-85) that contained parvalbumin immunoreactivity were also observed. In knockout mice, however, Mes5 neurons could not be detected. The area of brainstems which normally contained the Mes5 was devoid of parvalbumin-immunoreactive proprioceptors. The present study suggests that Brn-3a is required for the development of proprioceptors but not motoneurons in the trigeminal nervous system.

Effect of Brn-3a deficiency on primary nociceptors in the trigeminal ganglion

Immunohistochemistry for substance P, somatostatin and vanilloid receptor subtype 1 as well as receptors for somatostatin and opioids was performed on the trigeminal ganglion in wild-type and Brn-3a knockout mice at postnatal day 0. In wild-type mice, the trigeminal ganglion contained abundant substance P-, vanilloid receptor subtype 1-, sst2A receptor- and delta-opioid receptor-immunoreactive neurons, while the ganglion had only a few mu-opioid receptor-immunoreactive neurons. The Brn-3a deficiency had an effect on the cell size but not the number of substance P-immunoreactive neurons. In knockout mice, the proportion of small immunoreactive neurons markedly increased and that of medium- to large-sized immunoreactive ones correspondingly decreased (mean +/- S.D. = 54.7 +/- 29.1 microm2, range = 10.9-220.8 microm2) compared to wild-type mice (mean +/- S.D. = 116.6 +/- 58.6 microm2, range = 27.3-400.7 microm2). As for vanilloid receptor subtype 1-immunoreactive neurons, the number and cell size was barely affected by the deficiency. On the other hand, the loss of Brn-3a caused a decrease in the number of sst2A receptor- or delta-opioid receptor-immunoreactive neurons (more than 95% reduction) and an increase in the number of mu-opioid receptor-immunoreactive neurons (9.3-fold increase). Somatostatin-immunoreactive neurons were not detected in the trigeminal ganglion of wild-type or mutant mice at postnatal day 0. The present study suggests that Brn-3a deficiency may have effects on the survival of trigeminal nociceptors and their expression of some neurochemical substances.

Effect of Brn-3a deficiency on parvalbumin-immunoreactive primary sensory neurons in the dorsal root ganglion

Immunohistochemistry for parvalbumin, a marker for primary proprioceptors, was performed on the dorsal root ganglion (DRG) of wildtype and knockout mice for Brn-3a at postnatal day 0 and embryonic day 18.5. The DRG contained many parvalbumin-immunoreactive (ir) neurons in wildtype (5.4%) and knockout mice (5.6%). Cell size analysis demonstrated that such neurons were mostly medium-sized to large in these mice. Therefore, it is unlikely that the survival of proprioceptors is dependent upon Brn-3a in the DRG. In the dorsal column and gray matter of the spinal cord of knockout mice, however, parvalbumin-ir nerve fibers were sparse compared to wildtype mice. The number of parvalbumin-ir varicosities around motoneurons decreased in the mutant. Thus, our data suggest that Brn-3a may play an important role in the central projection and terminal formation of DRG proprioceptors in the spinal cord.