The Effect of Different Surgical Methods on the Number of Circulating Tumor Cells in the Peripheral Blood of Patients with Renal Cell Carcinoma

Objective: The objective is to explore the effects of different surgical methods-retroperitoneal laparoscopic radical nephrectomy (RLRN) and open radical nephrectomy (ORN) on the number of circulating tumor cells (CTC) in the peripheral blood of patients with renal cancer. Methods: The clinical data of 63 patients in the Department of Urology, Affiliated Hospital of Chengde Medical College who underwent radical surgery for renal cancer were divided into CTC positive group (18 cases of open surgery and 16 cases of minimally invasive surgery) and CTC negative group (14 cases of open surgery), 15 cases of minimally invasive surgery), overall group (32 cases of open surgery, 31 cases of minimally invasive surgery). Observe the changes in the number of CTC 1 week before operation and 1 week after operation. Results: In the positive group, whether it was open surgery or minimally invasive surgery, the postoperative CTC level of patients was significantly reduced (P < 0.05). In the negative group, the CTC decreased significantly after open surgery (P > 0.05), and the CTC level decreased significantly after minimally invasive surgery (P < 0.01). In the overall group, both open and minimally invasive surgery CTC decreased significantly, and the difference was statistically significant (P < 0.05). Conclusion: The two different surgical methods can reduce the level of CTC, but compared with ORN, RLRN can significantly reduce the number of postoperative CTC. Patients in the CTC-negative group may be less suitable for open surgery. CTC levels have certain potential in the selection and guidance of treatment modes for patients with renal cell carcinoma (RCC).

Improving precision in the assessment of round cell numbers in human semen

The aim of this study was to increase the precision of assessment of the number of round cells observed in the per- oxidase test for detection of seminal leukocytes （granulocytes）. The dilution of semen was reduced and the volume of suspension examined was increased for semen samples containing between 0.6 and 6 million round cells per mL. A 1 ＋ 5 （1：6） dilution was compatible with measurable peroxidase activity and a sufficiently clear background for cell assessment. At this dilution, and with assessment of all 18 grids on both sides of the Neubauer-improved counting chamber, only three of the 10 samples （nominal cell concentrations of 1.9 ×10^-6-3.3×10^-6 mL-1） presented 400 round cells or more. As lower seminal dilutions were incompatible with easy detection of round cells or their peroxidase reaction product, it was not pos- sible to provide precise measurements （sampling error 5%） of the suggested lower reference limit of 1 ×10^-6 cells per mL. The results indicate that this poor precision of measuring 1×10^-6 round cells per mL could explain the discrepant reports on the acceptability of the cut-off values for leukocytospermia. Such reference limits need to be established with statistically sound methods.

Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

Neural stem cells promote neuronal regeneration and repair of brain tissue after injury,but have limited resources and proliferative ability in vivo.We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews,a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research.We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38,and added nerve growth factor（100 μg/L） to the culture medium.Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls.After 3 days,fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells.These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

Hi-Tag:a simple and efficient method for identifying protein-mediated long-range chromatin interactions with low cell numbers

Protein-mediated chromatin interactions can be revealed by coupling proximity-based ligation with chromatin immunoprecipitation.However,these techniques require complex experimental procedures and millions of cells per experiment,which limits their widespread application in life science research.Here,we develop a novel method,Hi-Tag,that identifies high-resolution,long-range chromatin interactions through transposase tagmentation and chromatin proximity ligation(with a phosphorothioate-modified linker).Hi-Tag can be implemented using as few as 100,000 cells,involving simple experimental procedures that can be completed within 1.5 days.Meanwhile,Hi-Tag is capable of using its own data to identify the binding sites of specific proteins,based on which,it can acquire accurate interaction information.Our results suggest that Hi-Tag has great potential for advancing chromatin interaction studies,particularly in the context of limited cell availability.

Effect of Salinity on the Composition, Number and Size of Epidermal Cells along the Mature Blade of Wheat Leaves

Salinity inhibits leaf growth in association with changes in cell size. The objective of this study was to determine the spatial distributions of the composition, number and dimensions of epidermal cells in the mature blades of leaf four of wheat seedlings under saline conditions. Plants were grown in loamy soil either with or without 120 mmol/L NaCl in a growth chamber, and harvested after leaf four was fully developed. The results of the spatial distribution analyses of width along the blade showed that salinity not only reduced the width of the leaf blade, but that it also altered the distribution pattern of blade width along the leaf axis. The reduction in the final size of the leaf blade was associated with a reduction in the total number of epidermal cells and in their widths and lengths. This study also revealed the spatial effects of salinity on the blade and epidermal cell dimensions along the leaf axis. In particular, salinity inhibited the total cell number for interstomatal, sister and elongated cells, implying that cell division in wheat leaves is inhibited by salinity. However, the lengths of interstomatal cells were not affected by salinity （unlike those for the sister and elongated cells）, suggesting the relative contributions of cell length and numbers to the reduction in the final length of the blade under salinity is dependent on cell type.

Key genes and mechanisms underlying natural variation of silique length in oilseed rape(Brassica napus L.)germplasm

Silique length influences seed yield in oilseed rape.It shows extensive variation in germplasm resources,and identifying the underlying genes and regulatory mechanisms would advance breeding for the trait.In the present study,a genome-wide association study(GWAS)using 331 core accessions planted in 10 environments revealed 13 loci associated with silique length on chromosomes A01,A04,A07,A09,and C03,explaining 6.2%–19.2%of phenotypic variance.Physiological analysis showed that silique length variation was attributable to differences in silique growth rate and/or duration before four weeks after flowering,with levels of endogenous phytohormones(auxin,ethylene,and GA24,GA12,and GA44)playing an important role.Cytological analysis showed that silique length variation was due mainly to differences in cell number followed by cell size.Transcriptomic analysis of two pools of silique walls with opposite length extremes revealed 3248 differentially expressed genes(DEGs).These DEGs were enriched in several pathways(such as cell wall,cell division,and hormone metabolism)associated with cell proliferation and expansion and silique development.Integrating GWAS,RNA-seq,and functional annotation results revealed 15 candidate genes for the major associated locus q SL.A09-3.Of these,Bna A9.ARF18 and Bna A9.CYP78 A9 were validated by haplotype analysis followed by candidate gene association.Sequence variation in the coding region of Bna A9.ARF18 and expression of Bna A9.CYP78 A9 in silique walls were strongly associated with silique length.Our results provide an explanation for the natural variation of silique length in oilseed rape germplasm and offer useful information for its improvement.

An approach for choosing discretization schemes and grid size based on the convection-diffusion equation

A new approach for selecting proper discretization schemes and grid size is presented. This method is based on the convection-diffusion equation and can provide insight for the Navier-Stokes equation. The approach mainly addresses two aspects, i.e., the practical accuracy of diffusion term discretization and the behavior of high wavenum- ber disturbances. Two criteria are included in this approach. First, numerical diffusion should not affect the theoretical diffusion accuracy near the length scales of interest. This is achieved by requiring numerical diffusion to be smaller than the diffusion discretization error. Second, high wavenumber modes that are.much smaller than the length scales of interest should not be amplified. These two criteria provide a range of suitable scheme combinations for convective flux and diffusive flux and an ideal interval for grid spacing. The effects of time discretization on these criteria are briefly discussed.

The preliminary study of the phytoplankton ecology in the Great Wall Bay，Antarctica

This paper presents the identification and quantitative analysis of the phytoplankton samples collected in the Great Wall Bay, Antarctica from March 1988 to February 1989. The results indicate that the specific composition of phytoplankton clearly shows their ecological characteristics. That is the community mainly composed of cold-water species and neritic-eurythermal species. The dominant species altered with seasonal variation, their number showed the high-peak in the austral summer and the abundance of phytoplankton in each month mainly depended upon the dominant species. The distribution of phytoplankton is influenced by many environmental factors. Among them the hours of sunshine are the main factor.

Optimization of Band Gap of 1D Elastic Metamaterial Under Impact Load by Regulating Stiffness

Designing materials that mitigate impacts effectively are crucial for protecting people and structures.Here,a single-resonator metamaterial with negative mass characteristics is proposed for impact mitigation,and numerical analysis of wave propagation shows explicitly how the spring stiffness and number of unit cells influence that mitigation.The results show clearly that a metamaterial with differing microstructural stiffness is better at mitigating the effect of a shock wave than one with a unique stiffness.Also,there is a critical number of unit cells beyond which the shock wave is not attenuated further,but the fabrication complexity increases.In the 40 groups of microstructural regions in this example,the attenuation effect no longer increases when there are more than 35 groups.This work offers guidance for microstructure designs in metamaterials and provides new ideas for using metamaterials to mitigate shock waves.

Proliferation and adipogenic differentiation of human adipose-derived stem cells isolated from middle-aged patients with prominent orbital fat in the lower eyelids

Aim:To evaluate the age-related effects on the adipogenic differentiation and proliferation potentials of human orbital adipose-derived stem cells(OASCs).Methods:Orbital adipose samples were harvested from the central fat compartment in the lower eyelids of 10 young and middle-aged patients during routine blepharoplasty surgery.After assessment of the morphological changes of adipocytes with aging,OASCs were isolated from the fat samples and expanded in vitro.Differences in the stem cell colony number(fibroblast colony-forming unit),growth rate and phenotype characterization(flow cytometry analysis)were evaluated.The ability of OASCs to differentiate into adipocytes was determined by oil red O staining and the mRNA expression level of peroxisome proliferator-activated receptorγ.Results:Fat cell size showed a decreasing trend with advancing age.Although no difference was found in the expression of cell surface markers,the colony number and proliferative rate of OASCs from middle-aged donors were significantly lower than those from the young donors.The adipogenic differentiation capacity of middle-aged OASCs was also reduced.These differences were statistically significant(P<0.001).Conclusion:The data showed that the progenitor cell number,proliferation capacity and adipogenic potential of OASCs decreased with aging,suggesting that using OASCs from elderly patients for therapeutic purposes might be restricted.

Expression of a rice OsARGOS gene in Arabidopsis promotes cell division and expansion and increases organ size

The ARGOS gene in Arabidopsis plays a key role in controlling plant organ size. To determine the function of it＇s ortholog in rice, a putative ARGOS orthologous gene from rice tissues was isolated and designated as OsARGOS. This gene has only one copy in the rice genome. OsARGOS transcripts were detected in most of rice tissues, particularly in the young tissues, and its expression was induced in rice seedlings by the application of either auxin or cytokinin. Arabidopsis plants expressing OsARGOS led to larger organs, such as leaves and siliques, compared with wild-type plants. Interestingly, the root growth was also enhanced in these transgenic Arabidopsis plants. Therefore, the biomass of the transgenic plants was significantly increased. Further analysis revealed that, different from the ARGOS and ARGOS-LIKE genes in Arabidopsis, the OsARGOS gene enlarged organ by an increase in both cell number and cell size. In addition, the transcript levels of several organ size-associated genes regulating either cell division or cell growth were upregulated in the transgenic Arabidopsis plants. We also transferred the OsARGOS gene to rice, but the transgenic plants did not show any changes in organ size compared with the control plants. It is likely that the function of OsARGOS in organ size control depends on other size regulators in rice. The expression of OsARGOS in Arabidopsis may activate the signaling pathways that control cell proliferation and cell expansion during the course of plant growth and development. Since the expression of OsARGOS causes organ enlargement, the potential application of this gene through genetic engineering may significantly improve the production of biomass in agricultural practice.

Overexpression of a New Putative Membrane Protein Gene AtMRB1 Results in Organ Size Enlargement in Arabidopsis

Arabidopsis AtMRB1 is predicted to encode a novel protein of 432 amino acid residues in length, with four putative transmembrane domains. In the present study, characterization of AtMRB1 is conducted. Green fluorescent protein （GFP） fusion protein assay showed that AtMRB1 was located in the plasma membrane. Transgenic lines overexpressing AtMRB1 driven by a CaMV 35S promoter were generated. Statistic analysis showed that, during the seedling stage, the organ sizes of the transgenic lines including hypocotyl length, root length and root weight were significantly larger than those of the wild type plants under both light and dark conditions. In the adult plant stage, the AtMRB1 overexpressor plants were found to have larger organ sizes in terms of leaf length and width, and increased number of cauline leaves and branches when bolting. Further observation indicated that the larger leaf size phenotype was due to a larger number of mesophyll cells, the size of which was not altered. Quantitative real-time polymerase chain reaction analysis showed that the transcription of ANT, ROT3 and GRF5 were upregulated in the AtMRBl.overexpressor plants. These data suggest that AtMRB1 is possibly a positive regulator of organ size development in Arabidopsis, mainly through cell number control.