Comparing Arsenic-Containing Qinghuang Powder and Low-Intensity Chemotherapy in Elderly Patients with Acute Myeloid Leukemia

OBJECTIVE

To compare the clinical effect of arsenic-containing Qinghuang Powder (QHP) and low-intensity chemotherapy (LIC) in treatment of elderly acute myeloid leukemia (eAML) patients.

METHODS

Clinical data of 80 eAML patients treated at Xiyuan Hospital of China Academy of Chinese Medical Sciences from January 2015 to December 2020 were retrospectively analyzed. The treatment scheme was designed by real world study according to patients' preference, and patients were divided into a QHP group (35 cases) and a LIC group (45 cases). The median overall survival (mOS), 1-, 2-, and 3-year OS rates, and incidence of adverse events were compared between the two groups.

RESULTS

The mOS of 80 patients was 11 months, and the 1-, 2-, and 3-year OS rates were 45.51%, 17.96%, and 11.05%, respectively. The QHP and LIC groups demonstrated no significant difference in mOS (12 months vs. 10 months), 1- (48.57% vs. 39.65%), 2- (11.43% vs. 20.04%), and 3-year OS rates (5.71% vs. 13.27%, all P>0.05). Moreover, the related factors of mOS demonstrated no significant difference in patients with age>75 years (11 months vs. 8 months), secondary AML (11 months vs. 8 months), poor genetic prognosis (9 months vs. 7 months), Eastern Cooperative Oncology Group performance status score ⩾ 3 (10 months vs. 7 months) and hematopoietic stem cell transplant comorbidity index ⩾ 4 (11 months vs. 7 months) between the QHP and LIC groups (all P>0.05). However, the incidence of myelosuppression was significantly lower in the QHP group than that in the LIC group (28.57% vs. 73.33%, P<0.01).

CONCLUSIONS

QHP and LIC had similar survival rates in eAML patients, but QHP had a lower myelosuppression incidence. Hence, QHP can be an alternative for eAML patients who do not tolerate LIC.

[Explore the influence of vitamin D supplementation on clinical efficacy and drug retention rate of vedolizumab in patients with ulcerative colitis]

Objectives: To analyze the influence of vitamin D supplementation on clinical efficacy and drug retention rate of vedolizumab (VDZ) in patients with ulcerative colitis (UC). Methods: Retrospective study. By retrieving the clinical database of the Second Affiliated Hospital of Wenzhou Medical University, the patients with moderately to severely active UC were collected, who underwent VDZ treatment from January 2020 to June 2022. The modified Mayo score and Mayo endoscopic score (MES) were employed to evaluate disease activity and intestinal inflammation in UC patients, respectively. According to whether vitamin D was supplemented during VDZ treatment, the patients were divided into supplementary group and non-supplementary group. According to baseline serum 25(OH) D level, UC patients were divided into vitamin D deficiency group and non-deficiency group. According to whether vitamin D was supplemented, the patients of each group were divided into supplementary subgroup and non-supplementary subgroup, respectively. The clinical response rate, clinical remission rate and mucosal healing rate at week 30 after receiving VDZ treatment and the retention rate of VDZ at the 72nd week were observed. The effect of baseline serum 25 (OH) D level on the efficacy of vitamin D supplementation was analyzed by chi-square test. The effects of vitamin D supplementation on the clinical efficacy and drug retention of VDZ in UC were analyzed by chi-square test and Kaplan-Meier curve, respectively. Results: A total of 80 patients with moderately to severely active UC, who were aged (39.4±13.0) years(18-75 years), 37 male and 43 female, were included. There were 43 cases in supplementary group and 37 cases in non-supplementary group. There were 59 cases in the deficiency group, including 32 cases in the supplementary subgroup and 27 cases in the non-supplementary subgroup. There were 21 cases in the non-deficiency group, including 11 cases in the supplementary subgroup and 10 cases in the non-supplementary subgroup. At week 30, the average level of serum 25(OH) D was shown to be higher in supplementary group than that at week 0 [(24.5±5.4) vs (17.7±6.7) μg/L, P<0.001]. At week 30, in contrast with non-supplementary group, erythrocyte sedimentation rate(ESR)[75.0% (24.3%, 86.7%) vs 32.7% (-2.6%, 59.3%), P=0.005] and modified Mayo score [(4.7±2.8) vs (2.3±2.7) points, P<0.001] and MES score [(1.2±1.1) vs (0.4±0.9) points, P=0.001] were significantly reduced, clinical response rate [79.1%(34/43) vs 56.8%(21/37), P=0.032], clinical remission rate [67.4%(29/43) vs 29.7%(11/37), P=0.001] and mucosal healing rate [72.1%(31/43) vs 37.8%(14/37), P=0.002] were higher. At week 72, drug retention rate of VDZ was shown to be higher in supplementary group than in non-supplementary group [55.8%(24/43) vs 27.0%(10/37), P=0.004]. The further analysis showed that vitamin D supplementation could only improve clinical response rate[71.9%(23/32) vs 44.4%(12/27), P=0.033], clinical remission rate[62.5%(20/32) vs 14.8%(4/27), P<0.001], mucosal healing rate[68.8%(22/32) vs 22.2%(6/27), P<0.001] and drug retention rate [53.1%(17/32) vs 13.8%(4/27), P=0.001] in the patients with vitamin D deficiency. Conclusion: Vitamin D supplementation contributes to improving clinical response rate, clinical remission rate, mucosal healing rate and drug retention rate of VDZ in UC patients.

GRN is a prognostic biomarker and correlated with immune infiltration in glioma: A study based on TCGA data

Background

Among primary brain tumors, gliomas are associated with a poor prognosis and a median survival that varies depending on the tumor grade and subtype. As the most malignant form of glioma, glioblastoma (GBM) constitutes a significant health concern. Alteration in granulin(GRN) has been proved to be accountable for several diseases. However, the relationship between GRN and GBM remains unclear. We evaluated the role of GRN in GBM through The Cancer Genome Atlas (TCGA) database

Methods

First, we assessed the relationship between GRN and GBM through the GEPIA database. Next, the relationship between GRN and GBM prognosis was analyzed by logistic regression and multivariate cox methods. Using CIBERSORT and the GEPIA correlation module, we also investigated the link between GRN and immune infiltrates in cancer. Using the TCGA data, a gene set enrichment analysis (GSEA) was performed. We also employed Tumor Immune Estimation Resource (TIMER) to examine the data set of GRN expression and immune infiltration level in GBM and investigate the cumulative survival in GBM. We also validated tissues from GBM patients by Western blotting, RT-qPCR, and immunohistochemistry.

Results

Increased GRN expression was shown to have a significant relationship to tumor grade in a univariate study utilizing logistic regression. Furthermore, multivariate analysis disclosed that GRN expression down-regulation is an independent predictive factor for a favorable outcome. GRN expression level positively correlates with the number of CD4+ T cells, neutrophils, macrophages, and dendritic cells (DCs) that infiltrate a GBM. The GSEA also found that the high GRN expression phenotype pathway was enriched for genes involved in immune response molecular mediator production, lymphocyte-mediated immunity, cytokine-mediated signaling pathway, leukocyte proliferation, cell chemotaxis, and CD4+ alpha beta T cell activation. Differentially enriched pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) include lysosome, apoptosis, primary immunodeficiency, chemokine signaling pathway, natural killer cell-mediated cytotoxicity, and B cell receptor signaling pathway. Validated result showed that GRN was upregulated in GBM tissues. These results suggested that GRN was a potential indicator for the status of GBM.

Conclusion

GRN is a prognostic biomarker and correlated with immune infiltrates in GBM.

The spatial-temporal risk profiling of Clonorchis sinensis infection over 50 years implies the effectiveness of control programs in South Korea: a geostatistical modeling study

Background

Over the past 50 years, two national control programs on Clonorchis sinensis infection have been conducted in South Korea. Spatial-temporal profiles of infection risk provide useful information on assessing the effectiveness of the programs and planning spatial-targeted control strategies.

Methods

Advanced Bayesian geostatistical joint models with spatial-temporal random effects were developed to analyze disease data collecting by a systematic review with potential influencing factors, and to handle issues of preferential sampling and data heterogeneities. Changes of the infection risk were analyzed.

Findings

We presented the first spatial-temporal risk maps of C. sinensis infection at 5 × 5 km² resolution from 1970 to 2020 in South Korea. Moderate-to-high risk areas were shrunk, but temporal variances were shown in different areas. The population-adjusted estimated prevalence across the country was 5.99% (95% BCI: 5.09-7.01%) in 1970, when the first national deworming campaign began. It declined to 3.95% (95% BCI: 2.88-3.95%) in 1995, when the campaign suspended, and increased to 4.73% (95% BCI: 4.00-5.42%) in 2004, just before the Clonorchiasis Eradication Program (CEP). The population-adjusted prevalence was estimated at 2.77% (95% BCI: 1.67-4.34%) in 2020, 15 years after CEP started, corresponding to 1.42 (95% BCI: 0.85-2.23) million infected people.

Interpretation

The first nationwide campaign and the CEP showed effectiveness on control of C. sinensis infection. Moderate-to-high risk areas identified by risk maps should be prioritized for control and intervention.

Funding

The National Natural Science Foundation of China (project no. 82073665) and the Natural Science Foundation of Guangdong Province (project no. 2022A1515010042).

Genome-Wide Analysis of Odorant-Binding Proteins in Papilio xuthus with Focus on the Perception of Two PxutGOBPs to Host Odorants and Insecticides

In this study, we annotated 49 odorant-binding proteins (OBPs) in Papilio xuthus, with four novel genes and seven improved sequences. Expression profiles identified numerous OBPs in antennae or reproductive tissues. Using two antenna-enriched general OBPs (PxutGOBP1 and PxutGOBP2) as targets, we screened three key compounds by a reverse chemical ecology strategy. Of these, an oviposition stimulant vicenin-2 could strongly interact with PxutGOBP1, representing a dissociation constant (K_i) value of 10.34 ± 0.07 μM. Molecular simulations and site-directed mutagenesis revealed the importance of His66, Thr73, and Phe118 between PxutGOBP1 and vicenin-2 interactions. Two other compounds, an ordinary floral scent β-ionone and a widely used insecticide chlorpyrifos, exhibited high affinities to PxutGOBPs (K_i < 13 μM). Furthermore, two mutations His66Ala and Thr73Ala of PxutGOBP1 significantly reduced the binding to chlorpyrifos. Our study provides insights into the putative roles of PxutGOBPs in odorant perception and identifies key binding sites of PxutGOBP1 to vicenin-2 and chlorpyrifos.

[The associations of cyclin-dependent kinase inhibitor 2B antisense RNA 1 gene polymorphisms with the risk of Crohn's disease in Chinese patients]

Objectives: The present study aimed to investigate the associations of cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) gene polymorphisms with the risk of Crohn's disease (CD) in Chinese patients. Methods: From January 2012 to January 2021, a total of 207 CD patients and 545 age-and gender-matched healthy controls were collected from the Department of Gastroenterology, the Second Affiliated Hospital of Wenzhou Medical University. The genotypes of CDKN2B-AS1 (rs1063192, rs10757274, rs10757278, rs1333048, rs2383207) were determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry technique. Unconditional logistic regression analysis was used to analyze the differences of CDKN2B-AS1 polymorphisms between CD patients and healthy controls, as well as their influences on the clinicopathologic characteristics of CD patients. The analyses for linkage disequilibrium and haplotype were further performed by Haploview 4.2 software. Results: The variant genotype (AG+GG) and variant allele (G) of rs1063192 were more prevalent in CD patients than in healthy controls (32.4% vs 24.8%, P=0.036; 18.8% vs 13.6%, P=0.011). The same conclusions were also drawn for homozygous variant genotype (GG) and variant allele (G) of rs10757274 when CD patients were compared with healthy controls (19.8% vs 12.8%, P=0.017; 45.2% vs 38.1%, P=0.012). According to the Montreal Classification Standards, CD patients were stratified into different subgroups. The homozygous variant genotype (GG) and variant allele (G) of rs10757278 were less frequent in the patients with stricturing CD or penetrating CD than in those with non-stricturing and non-penetrating CD (13.7% vs 29.9%, P=0.015; 37.7% vs 50.4%, P=0.022). However, all the correlations above were no longer significant after Bonferroni's correction (all P>0.05). The polymorphic loci of rs10757274, rs2383207, rs10757278, and rs1333048 were in close linkage disequilibrium with each other in CDKN2B-AS1 gene. Compared with healthy controls, the frequency of haplotype AGAC was decreased in CD patients (1.5% vs 4.5%, χ²=7.61, P=0.006), whereas the frequency of haplotype GGAC was obviously increased in CD patients (3.0% vs 0.6%, χ²=14.25, P<0.001). The stratified analysis further showed that the frequency of haplotype AGAC was higher in the patients with stricturing CD or penetrating CD than in those with non-stricturing and non-penetrating CD (3.1% vs 0.4%, χ²=5.31, P=0.021). Conclusions: The variations of CDKN2B-AS1 (rs1063192, rs10757274, rs10757278, rs1333048, rs2383207) may not independently affect the risk of CD. Among the haplotypes constructed by rs10757274, rs2383207, rs10757278, and rs1333048, the haplotype AGAC may reduce the risk of CD, whereas it may increase the risk of stricturing or penetrating in CD patients. In addition, the haplotype GGAC may increase the risk of CD.

[Research progress on pharmacology of butylphthalide and its derivatives]

The butylphthalide(NBP), a colorless or light yellow viscous oily component isolated from celery seeds, has the effects of anti-inflammation, anti-oxidative stress, protecting blood-brain barrier, improving cerebral microcirculation, and promoting angiogenesis. It can protect the neurological function of patients with ischemic stroke through a variety of mechanisms, improve the symptoms of patients, and contribute to the long-term recovery of them. Therefore, independently developed in China, NBP was approved by State Food and Drug Administration for the clinical treatment of stroke patients in 2002. At the same time, owing to the complex multi-target pharmacological mechanism, NBP has been frequently used in clinical practice. As frequently verified, it has obvious effects in the treatment of other neurological diseases such as Alzheimer's disease, vascular dementia, Parkinson's disease, autoimmune diseases, depression, traumatic central nervous system injury. Moreover, it demonstrates significant pharmacological effects on non-neurological diseases such as diabetes mellitus and myocardial infarction. Therefore, this study summarizes the research progress on roles of NBP in nervous system diseases and non-nervous system diseases, and the pharmacological characteristics and mechanisms of NBP, which is expected to lay a basis for research on related targets.

Transcriptome analysis identifies candidate genes in the biosynthetic pathway of sex pheromones from a zygaenid moth, Achelura yunnanensis (Lepidoptera: Zygaenidae)

In most moth species, sex pheromones responsible for mating and communication of both sexes are primarily produced by the pheromone glands (PGs) of female moths. Although the PG transcriptomes and pheromone production related genes from 24 moth species have been characterized, studies on the related information remain unknown in the Zygaenidae family. Here, we sequenced the PG transcriptome of a zygaenid moth, Achelura yunnanensis. Such the sequencing resulted in the yields of 47,632,610 clean reads that were assembled into 54,297 unigenes, coupled with RNA sequencing data from 12 other tissues. Based on the transcriptome, a total of 191 genes encoding pheromone biosynthesis and degradation enzymes were identified, 161 of which were predicted to have full-length sequences. A comparative analysis among 24 moth species of nine families indicated that the numbers of the genes were variable, ranging from 14 in two Grapholita species to 191 in A. yunnanensis. Phylogenetic analysis in parallel with the expression data highlighted some key genes, including three △9 and four △11 desaturases, four fatty acyl-CoA reductases (FARs) clustering in the pgFAR clade, and three significantly antennae-enriched aldehyde oxidases. An extensive tissue- and sex- expression profile revealed a broad distribution of the genes, in which 128 relatives were detected in the PGs and 127 in the antennae. This study reports, for the first time, the gene repertoires associated with the pheromone production in Zygaenidae, and provides a valuable resource for exploring putative roles of the PG-enriched genes in A. yunnanensis.

Combined transcriptomic, proteomic and genomic analysis identifies reproductive-related proteins and potential modulators of female behaviors in Spodoptera litura

The common cutworm, Spodoptera litura, is a polyandrous moth with high reproductive ability. Sexual reproduction is a unique strategy for survival and reproduction of population in this species. However, to date available information about its reproductive genes is rare. Here, we combined transcriptomics, genomics and proteomics approaches to characterize reproductive-related proteins in S. litura. Illumina sequencing in parallel with the reference genome led to the yields of 12,161 reproductive genes, representing 47.83% of genes annotated in the genome. Further, 524 genes of 19 specific gene families annotated in the genome were detected in reproductive tissues of both sexes, some of which exhibited sex-biased and/or tissue-enriched expression. Of these, manual efforts together with the transcriptome analyses re-annotated 54 odorant binding proteins (OBPs) and 23 chemosensory proteins (CSPs) with an increase of 18 OBPs and one CSP compared to those previously annotated in the genome. Interestingly, at least 35 OBPs and 22 CSPs were transcribed in at least one reproductive tissue, suggestive of their involvement in reproduction. Further proteomic analysis revealed 2381 common proteins between virgin and mated female reproductive systems, 79 of which were differentially expressed. More importantly, 74 proteins exclusive to mated females were identified as transferred relatives, coupled with their specific or high expression in male reproductive systems. Of the transferred proteins, several conserved protein classes across insects were observed including OBPs, serpins, trypsins and juvenile hormone-binding proteins. Our current study has extensively surveyed reproductive genes in S. litura with an emphasis on the roles of OBPs and CSPs in reproduction, and identifies potentially transferred proteins serving as modulators of female post-mating behaviors.

Autophagy Gene Panel-Based Prognostic Model in Myelodysplastic Syndrome

Abnormal autophagy is related to the pathogenesis and clinical symptoms of myelodysplastic syndrome (MDS). However, the effect of autophagy-related genes (ARGs) on the prognosis of MDS remains unclear. Here, we examined the expression profile of 108 patients with MDS from the GSE58831 dataset, and identified 22 genes that were significantly associated with overall survival. Among them, seven ARGs were screened and APIs were calculated for all samples based on the expression of the seven ARGs, and then, MDS patients were categorized into high- and low-risk groups based on the median APIs. The overall survival of patients with high-risk scores based on these seven ARGs was shorter than patients with low-risk scores in both the training cohort (P = 2.851e-06) and the validation cohort (P = 9.265e-03). Additionally, API showed an independent prognostic indicator for survival in the training samples [hazard ratio (HR) = 1.322, 95% confidence interval (CI): 1.158–1.51; P < 0.001] and the validation cohort (HR = 1.05, 95% CI: 1–1.1; P < 0.01). The area under the receiver operating characteristic curve (AUROC) of API and IPSS were 43.0137 and 66.0274 in the training cohorts and the AUC of the validation cohorts were 41.5361 and 72.0219. Our data indicate these seven ARGs can predict prognosis in patients with MDS and could guide individualized treatment.

The ionotropic receptor gene family in Lepidoptera and Trichoptera: Annotation, evolutionary and functional perspectives

Lepidoptera (moths and butterflies) and Trichoptera (caddisflies), belonging to the superorder Amphiesmenoptera, are the most diverse insect orders as representatives of the terrestrial and aquatic insects, respectively. The insects of the two orders possess different biological and behavioral characteristics, especially their larvae, presumably resulting in the differences of the ionotropic receptor (IR) genes in numbers, sequence characteristics or gene structure. Here, we employed genomics, transcriptomics, bioinformatics, phylogenetics and molecular biology strategies to characterize the IR gene repertoire in Lepidoptera and Trichoptera. Genome and transcriptome analyses with exhaustive homology-based searches and manual efforts, in 32 lepidopterans and five trichopterans, led to the identification of 1449 genes encoding IRs with 1170 full-length sequences, representing the most comprehensive set of chemoreceptor superfamilies across the Amphiesmenoptera. Analysis of gene gains and losses in orthologous groups implied that some IRs were lost in related species, and multiple gene copies occurred mainly in divergent IRs (D-IRs) by gene duplications. Phylogenetic analysis of 2442 IR proteins from 67 species revealed that Lepidoptera and Trichoptera IRs could be classified into three subfamilies, i.e., 14 antennal IRs (A-IRs), five Lepidoptera-specific IRs (LS-IRs) and four D-IRs. Of the three subfamilies, A-IRs and LS-IRs members within orthologous groups exhibited high conservation of gene structure, but D-IRs shared extremely low amino acid identities (below 30%). Expression profiles revealed functional diversities of IRs from Bombyx mori and Papilio xuthus involving smell, taste or reproduction, in which some genes displayed sex-biased expression in antennae associated with specific chemosensory behaviors of female or male adults. Our current study has provided insights into the evolution, conservation and divergence of IRs between/within Lepidoptera and Trichoptera, and allows for further experiments to investigate IR functions.

A Social Group-Based Information-Motivation-Behavior Skill Intervention to Promote Acceptability and Adoption of Wearable Activity Trackers Among Middle-Aged and Older Adults: Cluster Randomized Controlled Trial

Background

Wearable activity trackers offer potential to optimize behavior and support self-management. To assist older adults in benefiting from mobile technologies, theory-driven deployment strategies are needed to overcome personal, technological, and sociocontextual barriers in technology adoption.

Objective

To test the effectiveness of a social group–based strategy to improve the acceptability and adoption of activity trackers by middle-aged and older adults.

Methods

A cluster randomized controlled trial was conducted among 13 groups of middle-aged and older adults (≥45 years) performing group dancing (ie, square dancing) as a form of exercise in Guangzhou from November 2017 to October 2018. These dancing groups were randomized 1:1 into two arms, and both received wrist-worn activity trackers and instructions at the baseline face-to-face assessment. Based on the Information-Motivation-Behavior Skill framework, the intervention arm was also given a tutorial on the purpose of exercise monitoring (Information), encouraged to participate in exercise and share their exercise records with their dancing peers (Motivation), and were further assisted with the use of the activity tracker (Behavior Skill). We examined two process outcomes: acceptability evaluated by a 14-item questionnaire, and adoption assessed by the uploaded step count data. Intention-to-treat analysis was applied, with the treatment effects estimated by multilevel models.

Results

All dancing groups were followed up for the postintervention reassessment, with 61/69 (88%) participants of the intervention arm (7 groups) and 56/80 (70%) participants of the control arm (6 groups). Participants’ sociodemographic characteristics (mean age 62 years, retired) and health status were comparable between the two arms, except the intervention arm had fewer female participants and lower cognitive test scores. Our intervention significantly increased the participants’ overall acceptability by 6.8 points (95% CI 2.2-11.4), mainly driven by promoted motivation (adjusted group difference 2.0, 95% CI 0.5-3.6), increased usefulness (adjusted group difference 2.5, 95% CI 0.9-4.1), and better perceived ease of use (adjusted group difference 1.2, 95% CI 0.1-2.4), whereas enjoyment and comfort were not increased (adjusted group difference 0.9, 95% CI –0.4-2.3). Higher adoption was also observed among participants in the intervention arm, who were twice as likely to have valid daily step account data than their controlled counterparts (adjusted incidence relative risk [IRR]=2.0, 95% CI 1.2-3.3). The average daily step counts (7803 vs 5653 steps/day for the intervention and control, respectively) were similar between the two arms (adjusted IRR=1.4, 95% CI 0.7-2.5).

Conclusions

Our social group–based deployment strategy incorporating information, motivation, and behavior skill components effectively promoted acceptability and adoption of activity trackers among community-dwelling middle-aged and older adults. Future studies are needed to examine the long-term effectiveness and apply this social engagement strategy in other group settings or meeting places.

Trial Registration

Chinese Clinical Trial Registry ChiCTR-IOC-17013185; https://tinyurl.com/vedwc7h.

Effects of stacking periodicity on the electronic and optical properties of GaAs/AlAs superlattice: a first-principles study

The effects of stacking periodicity on the electronic and optical properties of GaAs/AlAs superlattice have been explored by density functional theory calculations. Among the (GaAs)m/(AlAs)m, (GaAs)1/(AlAs)m and (GaAs)m/(AlAs)1 (m = 1 to 5) superlattices, the band gaps of (GaAs)m/(AlAs)1 superlattices decrease significantly as the layer of GaAs increases, and the cut-off wavelengths are found to locate in the near infrared region. For (GaAs)m/(AlAs)1 SLs, the conduction bands shift toward Fermi level, resulting in the smaller band gap, while conduction bands of (GaAs)1/(AlAs)n SLs slightly shift to higher energy, which lead to comparable band gaps. The layer number of GaAs shows negligible effects on the reflectivity spectra of superlattice structures, while the absorption coefficient shows a red-shift with the increasing layer of GaAs, which is beneficial for the application of GaAs/AlAs superlattice in the field of near infrared detector. These results demonstrate that controlling the number of GaAs layers is a good method to engineer the optoelectronic properties of GaAs/AlAs superlattice.

Arsenic-Containing Qinghuang Powder () is an Alternative Treatment for Elderly Acute Myeloid Leukemia Patients Refusing Low-Intensity Chemotherapy

OBJECTIVE

To analyze the overall survival (OS) of elderly acute myeloid leukemia (AML) patients treated with oral arsenic-containing Qinghuang Powder (, QHP) or low-intensity chemotherapy (LIC).

METHODS

Forty-two elderly AML patients treated with intravenous or subcutaneous LIC (1 month for each course, at least 3 courses) or oral QHP (3 months for each course, at least 2 courses) were retrospectively analyzed from January 2015 to December 2017. The main endpoints of analysis were OS and 1-, 2-, 3-year OS rates of patients, respectively. And the adverse reactions induding bone marrow suppression, digestive tract discomfort and myocardia injury were observed.

RESULTS

Out of 42 elderly AML patients, 22 received LIC treatment and 20 received QHP treatment, according to patients' preference. There was no significant difference on OS between LIC and QHP patients (13.0 months vs. 13.5 months, >0.05). There was no significant difference on OS rates between LIC and QHP groups at 1 year (59.1% vs. 70.0%), 2 years (13.6% vs. 15%), and 3 years (4.6% vs. 5.0%, all >0.05). Furthermore, there was no significant difference of OS on prognosis stratification of performance status > 2 (12 months vs. 12 months), age> 75 year-old (12.0 months vs. 12.5 months), hematopoietic stem cell transplant comorbidity index >2 (12 months vs. 13 months), poor cytogenetics (12 months vs. 8 months), and diagnosis of secondary AML (10 months vs. 14 months) between LIC and QHP patients (>0.05).

CONCLUSION

QHP may be an alternative treatment for elderly AML patients refusing LIC therapy.

Effects of Ag doping on the electronic and optical properties of CdSe quantum dots

Cadmium selenide (CdSe) nanocrystals are important photoelectric materials. Doping heterovalent impurities such as silver (Ag) in CdSe nanocrystal quantum dots (QDs) can provide additional charge carriers, which can significantly enhance the performance of CdSe QDs for their potential applications in high-efficiency photovoltaic devices. Using density functional theory (DFT) based calculations with the Heyd-Scuseria-Ernzerhof (HSE06) screened hybrid functional, we demonstrate that Ag doping can affect the structural, electronic and optical properties of CdSe QDs significantly. The location and number of Ag dopant atoms are critical factors for modifying the electronic structure, in particular the change of energy position and shape of the valence and conduction band edges. It is found that doping of Ag atoms into the core region of a CdSe nanoparticle induces metallic-like electronic characteristics with a dense number of electrons emerging at the Fermi level. However, incorporation of Ag dopant into the surface of a CdSe quantum dot introduces some mid-gap states that mainly consist of Se 4p states, and results in a new sub-bandgap electronic transition from mid-gap states to the conduction band. The calculated absorption spectra indicate that doping of just one or two Ag atoms greatly strengthens the absorption in the ultraviolet-visible regime and extends the absorption edges of CdSe QDs into the infrared regime. In particular, the spectra show a high-intensity absorption band between 424 and 600 nm with just 1 Ag atom incorporated into the CdSe QDs. Based on the improved absorption spectra, the present results provide a science-based strategy for designing Ag-doped CdSe QDs with enhanced visible light absorption for their application in high-efficiency photovoltaic devices.

[Consistency Analysis of Gene Mutation Sites of Bone Marrow Tumor DNA and Circulating Tumor DNA in Patients with Myelodysplastic Syndrome]

OBJECTIVE

To analyze the consistency of gene mutation sites between bone marrow DNA (BM-tDNA) and perepheral plasma circulating tumor DNA (PP-ctDNA) in patients with myelodysplastic syndrome (MDS).

METHODS

The simultaneous sampled BM and PP from 19 patients (SBPP) was detected by NGS-127 gene panel, and the consistency of VAF between BM-tDNA and PP-ctDNA was analyzed. The peripheral blood cell tumor DNA (PC-tDNA) of 5 out of 19 patients was detected randomly, the consistency of VAF among PC-tDNA，BM-tDNA and PP-ctDNA was analyzed. The non simultaneous sampled BM and PP from 13 patients (NBPP) was detected, and the difference value of VAF between BM-tDNA and PP-ctDNA in SBPP and NBPP was analyzed.

RESULTS

The average concentration of PP-ctDNA in SBPP was 0.59 ng/µl and 0.604 ng/µl in NBPP. The median concentration of PP-ctDNA in SBPP and NBPP was 0.330 ng/µl and 0.338 ng/µl, respectively. The study showed a good consistency of VAF between BM-tDNA and PP-ctDNA in the SBPP (R²=0.9693, P<0.05), and the consistency of VAF between BM-tDNA and PP-ctDNA in single base replacement (SNP) sites (R²=0.9712) was better than that in insertion deletion (Indel) sites (R²=0.6813). The results showed a good consistency of VAF between BM-tDNA and PP-ctDNA both in 12 patients before treatment (R²=0.9325, P<0.05) and 5 patients (R²=0.9875, P<0.05) after treatment. The results also showed that the VAF of PC-tDNA had a good consistency with the VAF of BM-tDNA (R²=0.8783) and PP-ctDNA (R²=0.8783) (P<0.05). The difference value of VAF between BM-tDNA and PP-ctDNA in SBPP was significantly lower than that in NBPP (P<0.05).

CONCLUSION

PP can replace BM as a biological sample for genes mutation detection in patients with MDS due to its stable concentration, high degree of consistency with bone marrow in clinical significant mutation sites and easy collection.

A comparative study of low energy radiation response of AlAs, GaAs and GaAs/AlAs superlattice and the damage effects on their electronic structures

In this study, the low energy radiation responses of AlAs, GaAs and GaAs/AlAs superlattice are simulated and the radiation damage effects on their electronic structures are investigated. It is found that the threshold displacement energies for AlAs are generally larger than those for GaAs, i.e., the atoms in AlAs are more difficult to be displaced than those in GaAs under radiation environment. As for GaAs/AlAs superlattice, the Ga and Al atoms are more susceptible to the radiation than those in the bulk AlAs and GaAs, whereas the As atoms need comparable or much larger energies to be displaced than those in the bulk states. The created defects are generally Frenkel pairs, and a few antisite defects are also created in the superlattice structure. The created defects are found to have profound effects on the electronic properties of GaAs/AlAs superlattice, in which charge transfer, redistribution and even accumulation take place, and band gap narrowing and even metallicity are induced in some cases. This study shows that it is necessary to enhance the radiation tolerance of GaAs/AlAs superlattice to improve their performance under irradiation.

Impact of isovalent and aliovalent substitution on the mechanical and thermal properties of Gd2Zr2O7

In this study, a density functional theory method is employed to investigate the effects of isovalent and aliovalent substitution of Sm³⁺ on the phase stability, thermo-physical properties and electronic structure of Gd₂Zr₂O₇. It is shown that the isovalent substitution of Sm³⁺ for Gd³⁺ results in the formation of Gd₂Zr₂O₇-Sm₂Zr₂O₇ solid solution, which retains the pyrochlore structure and has slight effects on the elastic moduli, ductility, Debye temperature and band gap of Gd₂Zr₂O₇. As for the aliovalent substitution of Sm³⁺ for Zr⁴⁺ site, a pyrochlore-to-defect fluorite structural transition is induced, and the mechanical, thermal properties and electronic structures are influenced significantly. As compared with the Gd₂Zr₂O₇, the resulted Gd₂Sm_yZr_2-yO₇ compositions have much smaller elastic moduli, better ductility and smaller Debye temperature. Especially, an amount of electrons distribute on the fermi level and they are expected to have larger thermal conductivity than Gd₂Zr₂O₇. This study suggests an alternative way to engineer the thermo-physical properties of Gd₂Zr₂O₇ and will be beneficial for its applications under stress and high temperature.

Ab initio molecular dynamics simulation of low energy radiation responses of α-Al2O3

In this study, an ab initio molecular dynamics method is employed to investigate the response behavior of α-Al2O3 to low energy irradiation. Different from the previous experiments, our calculations reveal that the displacements of oxygen dominate under electron irradiation and the created defects are mainly oxygen vacancy and interstitial. The experimental observation of the absorption peaks appearing at 203, 233 and 256 nm for α-Al2O3 under electron irradiations should be contributed by the oxygen defects and these defects will reduce the transmittance of α-Al2O3, which agrees well with the very recent experiment. This study demonstrates the necessity to reinvestigate the threshold displacement energies of α-Al2O3, and to introduce recombination center for oxygen defects to improve its optical properties and performance under radiation environment.

Theoretical prediction of long-range ferromagnetism in transition-metal atom-doped d0 dichalcogenide single layers SnS2 and ZrS2

We have systematically investigated the effects of transition-metal (TM) atom (Sc-Zn) doping in 2D d⁰ materials SnS₂ and ZrS₂via the density functional theory method. Our results demonstrate that the conductivity and magnetism of SnS₂ and ZrS₂ can be engineered to spin-polarize half-metal/metal with appropriate TM dopants. For both materials, nontrivial magnetic interactions can be induced by V/Cr/Mn/Fe/Co doping. Specifically, the various behaviors of the magnetic exchanges in TM-doped SnS₂ and ZrS₂ are due to the competition between the super-exchange, the double exchange, and the p-d exchange interactions, which are dependent on the dopants' chemistry and spatial positions. Thus, our results give potential guidance for future experiments to create functionalized d⁰ nano-electronic devices.

Engineering the electronic and magnetic properties of d(0) 2D dichalcogenide materials through vacancy doping and lattice strains

We have systematically investigated the effects of different vacancy defects in 2D d(0) materials SnS2 and ZrS2 using first principles calculations. The theoretical results show that the single cation vacancy and the vacancy complex like V-SnS6 can induce large magnetic moments (3-4 μB) in these single layer materials. Other defects, such as V-SnS3, V-S, V-ZrS3 and V-ZrS6, can result in n-type conductivity. In addition, the ab initio studies also reveal that the magnetic and conductive properties from the cation vacancy and the defect complex V-SnS6 can be modified using the compressive/tensile strain of the in-plane lattices. Specifically, the V-Zr doped ZrS2 monolayer can be tuned from a ferromagnetic semiconductor to a metallic/half-metallic material with decreasing/increasing magnetic moments depending on the external compressive/tensile strains. On the other hand, the semiconducting and magnetic properties of V-Sn doped SnS2 is preserved under different lattice compression and tension. For the defect complex like V-SnS6, only the lattice compression can tune the magnetic moments in SnS2. As a result, by manipulating the fabrication parameters, the magnetic and conductive properties of SnS2 and ZrS2 can be tuned without the need for chemical doping.

Ab initio molecular dynamics simulation of the effects of stacking faults on the radiation response of 3C-SiC

In this study, an ab initio molecular dynamics method is employed to investigate how the existence of stacking faults (SFs) influences the response of SiC to low energy irradiation. It reveals that the C and Si atoms around the SFs are generally more difficult to be displaced than those in unfaulted SiC, and the corresponding threshold displacement energies for them are generally larger, indicative of enhanced radiation tolerance caused by the introduction of SFs, which agrees well with the recent experiment. As compared with the unfaulted state, more localized point defects are generated in faulted SiC. Also, the efficiency of damage production for Si recoils is generally higher than that of C recoils. The calculated potential energy increases for defect generation in SiC with intrinsic and extrinsic SFs are found to be higher than those in unfaulted SiC, due to the stronger screen-Coulomb interaction between the PKA and its neighbors. The presented results provide a fundamental insight into the underlying mechanism of displacement events in faulted SiC and will help to advance the understanding of the radiation response of SiC with and without SFs.

Association between the rs189037 single nucleotide polymorphism in the ATM gene promoter and cognitive impairment

The aim of this study was to explore the existence of a relationship between the rs189037 single nucleotide polymorphism (SNP) of the ataxia telangiectasia mutated (ATM) gene and cognitive impairment in the elderly (aged 60 years and above). In a cohort, 505 residents of Suinung City were consecutively recruited and their cognitive function was measured using a 30-point Mini-Mental State Examination (MMSE). The subjects were divided into cognitive impairment group and control group on the basis of MMSE scores. Presence of the rs189037 SNP variant was examined using polymerase chain reaction-restriction fragment length polymorphism. The prevalence rates of cognitive impairment were 32.7% in the whole sample. The genotype frequencies of the rs189037 polymorphism were 33.5% (CC), 50.7% (CT), and 15.8% (TT); the C and T allele frequencies were 58.8 and 41.2%, respectively. No significant differences in the frequency distributions of the CC, CT and TT genotypes were observed between cognitively impaired and control groups. We found that the rs189037 SNP was not directly correlated with cognitive impairment among the elderly Chinese Han population.

Effects of ultrasound combined with ozone on the degradation of organophosphorus pesticide residues on lettuce

Methamidophos (MDP) and dichlorvos (DDVP) are organophosphorous pesticides which are commonly used for pest control in agriculture to obtain better yields.

Effects of surface defects on two-dimensional electron gas at NdAlO3/SrTiO3 interface

Density functional theory calculations of NdAlO₃/SrTiO₃ heterostructure show that two-dimensional electron gas (2-DEG) is produced at the interface with a built-in potential of ~0.3 eV per unit cell. The effects of surface defects on the phase stability and electric field of 2-DEG have been investigated. It is found that oxygen vacancy is easily to form on the NdAlO₃(001) surface, with a low threshold displacement energy and a low formation energy. This point defect results in surface reconstruction and the formation of a zigzag -Al-O-Al- chain, which quenches the built-in potential and enhances the carrier density significantly. These results will provide fundamental insights into understanding how surface defects influence the electronic behavior of 2-DEG and tuning their electronic properties through surface modification.

Salt-induced epithelial-to-mesenchymal transition in Dahl salt-sensitive rats is dependent on elevated blood pressure

Dietary salt intake has been linked to hypertension and cardiovascular disease. Accumulating evidence has indicated that salt-sensitive individuals on high salt intake are more likely to develop renal fibrosis. Epithelial-to-mesenchymal transition (EMT) participates in the development and progression of renal fibrosis in humans and animals. The objective of this study was to investigate the impact of a high-salt diet on EMT in Dahl salt-sensitive (SS) rats. Twenty-four male SS and consomic SS-13^BN rats were randomized to a normal diet or a high-salt diet. After 4 weeks, systolic blood pressure (SBP) and albuminuria were analyzed, and renal fibrosis was histopathologically evaluated. Tubular EMT was evaluated using immunohistochemistry and real-time PCR with E-cadherin and alpha smooth muscle actin (α-SMA). After 4 weeks, SBP and albuminuria were significantly increased in the SS high-salt group compared with the normal diet group. Dietary salt intake induced renal fibrosis and tubular EMT as identified by reduced expression of E-cadherin and enhanced expression of α-SMA in SS rats. Both blood pressure and renal interstitial fibrosis were negatively correlated with E-cadherin but positively correlated with α-SMA. Salt intake induced tubular EMT and renal injury in SS rats, and this relationship might depend on the increase in blood pressure.

Ab initio molecular dynamics simulations of threshold displacement energies in SrTiO3

Ab initio molecular dynamics simulations have been carried out to study low energy recoil events in SrTiO3. The threshold displacement energies are shown to be strongly dependent on both the orientation and the corresponding atomic arrangement. The minimum threshold displacement energies are 13 eV for an O recoil along the <100> O-O chain, 25 eV for a Sr recoil along the <100> Sr-Sr chain and 38 eV for a Ti recoil along the <110> Ti-Ti chain. The weighted average threshold displacement energies along the primary crystallographic directions are 35.7, 53.5 and >64.9 eV for O, Sr and Ti, respectively. The interstitial configurations produced by the recoil events are <100> and <111> split interstitials for O and Sr, respectively, together with a Ti interstitial occupying a distorted bridge position between two Sr sites. It is found that the recoil events in SrTiO3 are partial-charge transfer assisted processes, and the partial-charge transfer plays an important role in these recoil events.

Ab initio molecular dynamics simulations of overlapping recoil events in ThO₂

Ab initio molecular dynamics is used to study defect production and interactions from overlapping atomic recoil events in thoria. The pre-existing defects, charge redistribution, and structural distortion from an initial recoil event significantly affect the dynamics of defect production processes that occur from a subsequent overlapping recoil event. The final defect configurations and increase in system energy are dependent on the incident directions and sequence of the recoils. A linear relationship between system potential energy and charge transfer at the distance of closest approach between the recoil and atomic nuclei demonstrates the important role of charge transfer in the response of thoria to single and overlapping recoils.

Pressure induced structural transformation in Gd₂Ti₂O₇ and Gd₂Zr₂O₇

Ab initio total energy calculations have been performed to study the phase stability of Gd(2)Ti(2)O(7) and Gd(2)Zr(2)O(7) pyrochlores over the pressure range from 0 to 60 GPa. Both compounds are unstable under pressure, and phase transformations to the defect-cotunnite structure are predicted. The phase transformation pressure of 43.6 GPa for Gd(2)Ti(2)O(7) is considerably larger than the value of 13 GPa for Gd(2)Zr(2)O(7), in good agreement with experiments. The decreased structural stability of Gd(2)Zr(2)O(7) under pressure, relative to Gd(2)Ti(2)O(7), is a consequence of the lower compressibility of the ⟨Zr-O⟩ bond and the higher compressibility of the ⟨Gd-O⟩ bond. In addition, the Gd 4f electrons are found to have only a small effect in determining the pressure induced phase transformation.

Oxygen-induced magnetic properties and metallic behavior of a BN sheet

In this paper, an ab initio method has been employed to study the adsorption energies, electronic structures and magnetic properties of a BN sheet functionalized by an oxygen (O) atom. The adsorption process is typically exothermic, and some unusual properties can be revealed with different adsorption sites. The energy gap of the BN sheet narrows due to the strong hybridization between O and BN electronic states when the O locates above a BN bond or a nitrogen atom. Upon the adsorption of O above a B3N3 ring or a boron atom, the electrons of the O-adsorbed BN system are polarized, which gives rise to a magnetic moment of 2.0 μ(B). In this case, the Fermi level crosses the valence band, resulting in the O-adsorbed BN system being metallic. Furthermore, potential energy curve analysis shows that the magnetism and metallicity of the BN system can be modulated by the external temperature and pressure.

Threshold displacement energies and defect formation energies in Y2Ti2O7

Ab initio molecular dynamics simulations have been carried out to determine both threshold displacement energies, E(d), and corresponding defect configurations, and ab initio methods have been used to determine defect formation energies in Y(2)Ti(2)O(7). The minimum E(d) is found to be 27 eV for a Y recoil along the {100} direction, 31.5 eV for Ti atoms along the {100} direction, 14.5 eV for O(48f) atoms along the {110} direction and 13 eV for O(8b) atoms along the {111} direction. The average E(d) values along three directions determined here are 35.1, 35.4, 17.0 and 16.2 eV for yttrium, titanium, O(48f) and O(8b) atoms, respectively. Cation interstitials are observed occupying vacant 8a anion sites and bridge sites between two neighboring cations along the {010} direction after low energy recoil events. A systematic study of the defect formation energies suggests that cation interstitials that are located at 8a sites, at bridge sites along the {010} direction and in split configurations along the {010}, {110} or {111} direction are all stable configurations. It is suggested that the relative stability of cation interstitials may provide a pathway for driving irradiation induced amorphization in Y(2)Ti(2)O(7).

Ab initio molecular dynamics simulation of a pressure induced zinc blende to rocksalt phase transition in SiC

The high-pressure induced phase transformation from the zinc blende to rocksalt structure in SiC has been studied by the ab initio molecular dynamics method. The simulations showed that SiC passes through a tetragonal intermediate state before transforming to a monoclinic phase at 160 GPa. The mechanism for this phase transformation agrees well with recent ab initio MD simulations, in which the applied pressure was as high as ∼600 GPa, but in the present study the transformation occurs at much lower pressure.

[Immobilization of laccase on magnetic chitosan microspheres and study on its enzymic properties]

Laccase was immobilized on magnetic chitosan microspheres by using glutaraldehyde as cross-linking reagent. The immobilization conditions and characterization of the immobilized enzyme were investigated. immobilization conditions for laccase were: 10mL of 0.8mg/mL of laccase in phosphate buffer(0.1mol/L, pH 7.0) reacted with 50mg of magnetic chitosan microspheres at 25 degrees C for 1h and subsequently was kept at 4 degrees C for 2h. The immobilized enzyme exhibited the maximal activity at pH 3.0. The optimal temperatures for immobilized enzyme were 10 degrees C and 55 degrees C. The Km value of immobilized laccase for ABTS was 171.1 micromol/L in pH 3.0 phosphate buffer at 37 degrees C. Compared with free enzyme, the thermal, operational, and storage stabilities of the enzyme were increased after the immobilization.

First-principles study of the adsorption of cesium on Si(001)(2×1) surface

First-principles calculations based on density functional theory-generalized gradient approximation method have been performed on cesium adsorption on Si(001)(2 x 1) surface. The optimized geometries and adsorption energies have been obtained and the preferred binding sites have been determined for the coverage (Theta) of one monolayer and half a monolayer. At Theta = 0.5 ML the most stable adsorption site is shown to be T3 site. At Theta = 1 ML two Cs atoms are adsorbed at HH and T3 sites, respectively. It was found that the saturation coverage of Cs for the Si(001)(2 x 1)-Cs surface is one monolayer instead of half a monolayer. This finding supports the majority of experimental observations but does not support recent coaxial impact collision ion scattering spectroscopy investigations [Surf. Sci. 531, L340 (2003)] and He(+) Rutherford backscattering spectroscopy studies [Phys. Rev. B 62, 4545 (2000)]. Mulliken charge and overlap population analysis showed that the Cs-Si bond is indeed ionic rather than polarized covalent as generally assumed for alkali metal (AM) on Si(001)(2 x 1) surface. Geometrical structure analysis seems to have limitations in determining the nature of AM-substrate bond. We also found that the silicon surface is metallic and semiconducting for the coverages of 0.5 and 1 ML, respectively.

Generation of annexin V-positive platelets and shedding of microparticles with stimulus-dependent procoagulant activity during storage of platelets at 4 degrees C

BACKGROUND

The ability of propyl gallate to activate platelet factor 3 has been determined through the activated partial thromboplastin time, but its effect on phosphatidylserine has not been established.

STUDY DESIGN AND METHODS

A novel platelet activator, propyl gallate, was introduced to a study of platelets stored at 4 degrees C. The effects of storage on platelet coagulation activity, on phosphatidylserine, and on the shedding of activated and activable membrane particles (microparticles) were examined by activated plasma clotting time, and the effect on annexin V binding was examined by gated flow cytometry. The ratios of annexin V binding and microparticle shedding in stored platelet samples were compared with those in fresh platelets stimulated with propyl gallate.

RESULTS

Microparticle shedding by stored platelets compensated for the diminished procoagulant potential of intact platelets (shown as the total propyl gallate-dependent platelet factor 3 activity), which did not change during prolonged (20-day) storage, but levels of phosphatidylserine confined to microparticles increased dramatically as platelet counts fell. Both annexin V binding and microparticle shedding increased spontaneously with storage and artificially with propyl gallate stimulation. However, at the same level of annexin V binding, stored platelets shed more microparticles than did fresh platelets stimulated with propyl gallate.

CONCLUSION

Propyl gallate induces platelet procoagulant activity and annexin V binding. Stored platelets differ from fresh platelets in a lower reactivity to propyl gallate activation and a higher rate of microparticle shedding.

Development of optimal techniques for cryopreservation of human platelets. I. Platelet activation during cold storage (at 22 and 8 degrees C) and cryopreservation

Using the current blood bank storage conditions at 22 degrees C, the viability and function of human platelets can be maintained for only 5 days. This does not allow for the necessary and extensive banking of platelets needed to treat patients afflicted with thrombocytopenia, a side effect of many invasive surgeries such as cardiopulmonary bypass or bone marrow transplantation. The development of optimal techniques for long-term cryopreservation and banking of human platelets would provide the ability to greatly extend the viable life of the platelet and would fulfill an increasing and urgent need in many clinical applications. To determine the optimal techniques for platelet preservation, the expression of an activation marker, phosphatidylserine, on the platelet membrane during storage at 22 and 8 degrees C as well as during the different freezing preservation processes was examined using flow cytometry and annexin V binding assay. Human platelets were identified by both CD41 and light scatter in flow cytometry. In cryopreservation experiments, effects of the following factors on platelet activation were evaluated: (a) cryoprotective agents (CPAs) type: dimethyl sulfoxide (Me2SO), ethylene glycol (EG), and propylene glycol (PG), (b) CPA concentration ranging from 0 to 3 M, and (c) ending temperatures of a slow cooling process at -1 degrees C/min. Our results demonstrated that (a) approximately 50% of platelets were activated on days 7 and 16 at 22 and 8 degrees C, respectively; (b) platelets were not significantly activated after 30-min exposure to 1 M Me2SO, EG, and PG at 22 degrees C, respectively, and (c) there was a significant difference in cryoprotective efficacy among these three CPAs in preventing platelets from cryoinjury. After being cooled to -10 degrees C, 74% of the cryopreserved platelets survived (nonactivated) in 1 M Me2SO solution, while in 1 M EG and 1 M PG solutions, 62 and 42% of the platelets survived, respectively. Using the information that Me2SO consistently yields higher percentages of nonactivated platelets and does not seem to be cytotoxic to platelets for 30-min exposure time, this was found to be the optimal cryoprotective agent for platelets. In addition, significant Me2SO toxicity to platelets was not noted until Me2SO concentrations exceeded 2 M. Finally, a concentration of 1 M Me2SO proved to be the most effective at all cryopreservation ending temperatures tested (-10, -30, -60, and -196 degrees C). In conclusion, under the present experimental conditions, a storage temperature of 8 degrees C appeared to be much better than 22 degrees C. Although the potential chemical toxicity of 1 M Me2SO, EG, or PG is negligible, 1 M Me2SO was found to be optimum for cryopreservation of human platelets. PG has the least cryoprotective function for low-temperature platelet survival.

Aberrant elevation of tyrosine-specific phosphorylation in human gastric cancer cells

Phosphotyrosine-containing proteins in various human cancer cell lines were studied by immunoblotting with anti-phosphotyrosine antibody. Of 29 cell lines derived from oral epidermoid cancer, esophageal cancer, gastric cancer, colon cancer, pancreatic cancer, hepatocellular carcinoma and malignant melanoma, 3 of the 6 gastric cancer cells showed aberrant elevation of tyrosine-specific phosphorylation. On the other hand, both esophageal cancer cells and colon cancer cells, which were reported to have amplified epidermal growth factor receptor and activated p60v-src kinase, respectively, showed no apparent elevation of tyrosine-specific phosphorylation, and their profiles of phosphorylation were similar to that of normal human fibroblasts. Two gastric cancer cells, NUGC-4 and MKN-45, showed similar profiles of phosphorylation but their responses to growth factors differed from each other. Tyrosine phosphorylation in NUGC-4 was strongly activated by treatment with epidermal growth factor and quickly reduced by the acid treatment which is effective in removing growth factors from cellular surface receptors. On the contrary, phosphorylation in MKN-45 did not respond to either growth factor or acid treatment. These results suggest that NUGC-4 and MKN-45 have tyrosine kinases which are activated by different mechanisms but share similar substrates.

[Study on carcinogenic activity of several nickel compounds in mice]

This paper reports the result of the tumor in site induced by several nickel compounds in mice. Three nickel compounds (Ni3S2, NiCl, pure nickel powder) were injected separately to the right arm pit subcutaneously (5 mg/mouse). At the end of the 62nd week, the tested mice were sacrificed. Only nickel sulfide induced tumors in the site of injection, the incidence of tumor was 36%. The majority of the tumors were fibrosarcomas, only 2 rhabdomyosarcomas. The tumors might infiltrate into the surrounding tissues, a few metastasized to the liver and/or the lungs.

[Study on molecular hybridization with biotin-labelled HPV 16 DNA probe in human cervical carcinoma]

Biotin-labelled human papillomavirus (HPV) 16 type DNA probe was prepared by the techniques of molecular biology. And dot hybridization technique was used to detect the HPV 16 homologous sequences in the tissues DNA of human cervical carcinoma. The results indicated that 16 cases out of 28 of the human cervical carcinoma tissues were positive. The positive rate was 57%. The other 4 cases of normal uterine cervix tissues were negative. Only 1 in 4 chronic cervicitis tissues showed positive. The HPV 16 plasmid DNA, as the positive control group, showed strong positive, while lambda-phage DNA was negative. The results have shown that the genome of the HPV actually exists in the tissue of the cervical carcinoma and that there is a close relationship between the cervical carcinoma and HPV infection. This experiment adopted the Biotin-labelled HPV 16 DNA probe. And it may provide us with a quick and sensitive method for investigation of the infection of HPV and its role in the carcinogenesis of cervical carcinoma.