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Biomedical subjects

Jianfu Zhao

Publications and source records attributed to Jianfu Zhao.

7 recordsLinked to original sources

Integrated bulk and single-cell RNA sequencing reveals a prognostic neuro-mimicry signature in papillary thyroid carcinoma.

BACKGROUND: Cancer cells can acquire neuron-like characteristics ("neural mimicry") to promote progression. However, the role of specific ion channel genes in Papillary Thyroid Carcinoma (PTC) and their clinical significance remains unclear. METHODS: We included transcriptomic data from 521 PTC patients in the TCGA cohort. A neuron-specific gene set was used to screen for potential targets. We constructed a prognostic model using LASSO logistic regression. To verify the cellular origin of the signature, we performed single-cell RNA sequencing (scRNA-seq) analysis on the GSE184362 dataset. RESULTS: We established an 8-gene signature involving KCNN4, KCNN1, KCNT2, SNAP25, KCNK16, GABRG1, GABRG2, and GABRB2. The model demonstrated good predictive performance for lymph node metastasis, with an AUC of 0.721 (95% CI 0.677-0.765). Single-cell analysis of seven integrated tumor samples (N = 65,744 cells) confirmed that GABRB2 was specifically enriched in malignant thyrocytes (EPCAM+/KRT18+) at 200-fold higher detection rates than immune cells (20.0% vs. 0.1%, P ≈ 0), supporting tumor-intrinsic neural mimicry. High-risk patients showed immunosuppressive features with altered immune cell infiltration patterns. CONCLUSION: This study identifies a malignant cell-intrinsic signature for predicting PTC prognosis. Validated by single-cell data, our findings suggest that targeting ion channels may represent a potential therapeutic strategy for modulating neuro-immune interactions in thyroid cancer, pending experimental validation.

GABRB2↗

Replication and inheritance of Nocardia plasmid pC1.

Nocardia sp. C-14-1, isolated from acrylic fiber wastewater, can degrade long-chain alkanes and succinonitrile efficiently. Here we report the characterization of an indigenous plasmid pC1. The overall nucleotide sequence of pC1 consisted of 5841 bp. The five ORFs, encoding a DNA recombinase, replication protein (Rep(pC1)) and three proteins of unknown function, were predicted on pC1. The Rep(pC1) displayed its homology with the Rep of Rhodococcus large plasmid p33701, suggesting a theta type of replication. An Escherichia coli plasmid (containing the single rep(pC1) gene) propagated autonomously in low copy number in Nocardia or Rhodococcus, suggesting that rep(pC1) was an essential gene for plasmid replication. The plasmid (containing the single rep(pC1) gene) presented as inheritance unstable hints that other pC1 loci were required for the stable inheritance of plasmids. By comparison of the plasmid-borne Rep proteins, we classify Rhodococcus or Nocardia plasmids into four groups.

DNA Replication↗

Diversity of telomere palindromic sequences and replication genes among Streptomyces linear plasmids.

Streptomyces sp. linear plasmids and linear chromosomes usually contain conserved terminal palindromic sequences bound by the conserved telomeric proteins Tap and Tp, encoded by the tap and tpg genes, respectively, as well as plasmid loci required for DNA replication in circular mode when the telomeres are deleted. These consist of iterons and an adjacent rep gene. By using PCR, we found that 8 of 17 newly detected linear plasmids in Streptomyces strains lack typical telomeric tap and tpg sequences. Instead, two novel telomeres in plasmids pRL1 and pRL2 from the eight strains and one conserved telomere in pFRL1 from the other strains were identified, while multiple short palindromes were also found in the plasmids. The complete nucleotide sequence of pRL2 revealed a gene encoding a protein containing two domains, resembling Tap of Streptomyces and a helicase of Thiobacillus, and an adjacent gene encoding a protein similar to Tpg of Streptomyces and a portion of the telomere terminal protein pTP of adenoviruses. No typical iterons-rep loci were found in the three plasmids. These results indicate an unexpected diversity of telomere palindromic sequences and replication genes among Streptomyces linear plasmids.

Amino Acid Sequence↗

[Determination of triazines in surface water using solid phase extraction-high performance liquid chromatography].

A method was developed to monitor triazines in surface water using the combination of solid phase extraction (SPE) and high performance liquid chromatography. Four different SPE cartridges were tested for extracting six triazines, including atrazine (A), simazine (S), prometryn (P), desethylatrazine (DEA), 2-hydroxyatrazine (OHA) and desisopropylatrazine (DIA), and finally ENVI-18 was selected as optimal. The method for solid phase extraction was further systematically studied for details. Optimal results of orthogonal design were determined as follows: pH 6, 5 mL methanol as eluting solvent, and no methanol added into water sample before extraction. The detection limits of six triazines were 0.14 microg/L for P, 0.12 microg/L for A, 0.08 microg/L for S, 0.08 microg/L for DEA, 0.10 microg/L for OHA and 0.18 microg/L for DIA. This method was applied for environmental aquatic samples, and the results showed that the concentration of prometryn in a lake was detected as (9.33 +/- 0.27) microg/L, as well as the concentrations of atrazine and prometryn in a river were detected as (5.28 +/- 0.43) microg/L and (7.12 +/- 0.54) microg/L respectively.

English Abstract↗

[Ecological characteristics of phytoplankton in Suining tributary under bio-remediation].

Based on the analyses of phytoplankton community in the treated and untreated reaches of Suining tributary of Suzhou River, this paper studied the effects of bio-remediation on phytoplankton. As the result of the remediation, the density and Chl-a content of phytoplankton in treated reach were greatly declined, while the species number and Shannon-Wiener diversity index ascended obviously. The percentage of Chlorophyta and Baeillariophyta ascended, and some species indicating medium-and oligo-pollution were found. All of these illustrated that bio-remediation engineering might significantly benefit to the improvement of phytoplankton community structure and water quality.

Biodegradation, Environmental↗

[Screening of high efficiency succinonitrile degrading bacterium strains and their degradability].

Succinonitrile used as a sole source of carbon and nitrogen, two bacterium strains, named as J-1-3 and J-13-1, which had high degrading capacity for succinonitrile were isolated and screened out from acrylic fiber wastewater and biofilm in its treatment structure. Through morphological and biochemical method, the two strains were primarily identified as Pseudomonas spp. By tests in shaking flasks, it was determined that the strains can be optimum growth at 30 degrees C, with shaker rotary speed which indirectly reflected aeration capacity at 250 r/min, inoculum amount of 0.1%, and initial pH6. On the optimum conditions for growth, the degradation experiments on different initial concentrations of succinonitrile were carried out. The results indicate that the two strains, especially J-13-1 had high degrading efficiency for succinonitrile. With the initial concentration of succinonitrile at ca. 6000, 8000 and 10,000 mg/L, the degrading rates of succinonitrile by strain J-13-1 reached to 100% after 12.5 h, 14 h and 16 h, respectively.

Biodegradation, Environmental↗

[The relationship between environmental change and stable carbon isotopes records from tree-ring in Mt. Helan].

The value of stable carbon isotope in plants is closely correlative with environmental factors. The stable carbon isotope chronology was attained from tree-ring alpha-cellulose in pine(Pinus tabulacformis), Mt. Helan. The relation between delta 13C series and precipitation from January to July was negatively correlative(r = -0.515, alpha = 0.05). And the delta 13C series was positive correlative with the average temperature from June to August(r = 0.427, alpha = 0.05). Also the atmospheric CO2 content relates to the delta 13C series in the tree-ring cellulose. It was easy to find the increasing trend of CO2 composition in the atmosphere from the tree rings. By the relation between the number of sunspot and delta 13C series, the more number sunspot was correlated with higher delta 13C value was found.

Air↗