Biomedical subjects

Zhiyi Zhang

Publications and source records attributed to Zhiyi Zhang.

5 recordsLinked to original sources

PubMed2025

Proteomics and Phosphoproteomics Characteristics of the Rhesus Macaque Lung Infected With Original SARS-CoV-2, Delta, and Omicron Variants.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains mutate rapidly, making it crucial to study their molecular mechanisms for swift vaccine and drug development. Here, we utilized host lung proteomic and phosphoproteomic profiling to investigate the underlying pathology caused by the variants. Lung tissues infected with wild-type GD108, Delta, or Omicron BA.1 variants showed overexpression of proteins and phosphoproteins linked to the innate immune pathway, particularly in the Omicron group, with high activation of NOD-receptor and RIG-I like receptor signaling pathways. Protein-protein interaction (PPI) analysis revealed six key proteins, including antiviral innate immune response receptor RIG-I (DDX58), and five interferon-related proteins (IFIT2, ISG15, MX1, STAT1, and EIF2AK2), highlighting the importance of the innate immune response in combating all three variants. Kinase prediction analysis suggested that six kinases (DAPK1, DAPK2, DAPK3, PRACK, TTK, and MAP2K2), potentially inhibited by Fostamatinib, were activated across all three variants, and might be potential drug targets, pending further verification. Omicron infection, compared to other mutants, significantly disrupted proteins related to pulmonary structural support, like integrin and collagens, and inhibited efferocytosis, reducing the host's ability to eliminate the pathogen. These findings suggest that innate immune activation and structural disruption may contribute to Omicron-related pathology, potentially being useful for research into the molecular mechanisms underlying lung injury from SARS-CoV-2 variants.

Animals↗

PubMed2003

Role of calcium in phototoxicity of 2-butylamino-2-demethoxy-hypocrellin A to human gastric cancer MGC-803 cells.

After incubation with 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA), photodynamically induced change in the cytoplasmic free calcium concentration ([Ca(2+)](i)) and its effect on cell damage were investigated in human gastric cancer (MGC-803). Fluorescence spectrophotometry measurement indicated that the photosensitization of MGC-803 by 2-BA-2-DMHA caused an increase in intracellular calcium [Ca(2+)](i), and this increase in [Ca(2+)](i) showed a dependence on the concentration of 2-BA-2-DMHA, light dose and extracellular [Ca(2+)](e). This phenomenon of intracellular calcium accumulation was further confirmed by using laser scanning confocal microscopy (LSCM). Furthermore, the results from MTT assay and flow cytometry analysis suggested that chelation of extracellular calcium by EGTA or intracellular calcium by BAPTA could inhibit photodynamically induced cell killing, while increase of [Ca(2+)](i) by thapsigargin (TG), a highly specific inhibitor of the Ca(2+)-ATPase, or by A23187, a calcium ionophore could enhance this action. Meanwhile, the nucleus morphology was also investigated by fluorescence microscopy. The results indicated that the increase in intracellular Ca(2+) concentration was responsible for 2-BA-2-DMHA photodynamically induced damage to MGC-803.

Calcimycin↗

PubMed2002

A minimum distance estimation approach to the two-sample location-scale problem.

As reported by Kalbfleisch and Prentice (1980), the generalized Wilcoxon test fails to detect a difference between the lifetime distributions of the male and female mice died from Thymic Leukemia. This failure is a result of the test's inability to detect a distributional difference when a location shift and a scale change exist simultaneously. In this article, we propose an estimator based on the minimization of an average distance between two independent quantile processes under a location-scale model. Large sample inference on the proposed estimator, with possible right-censorship, is discussed. The mouse leukemia data are used as an example for illustration purpose.

Animals↗

PubMed2002

[Clinical significance of secondary cytoreductive surgery for recurrent advanced ovarian cancer].

OBJECTIVE: To study the role of secondary cytoreductive surgery (SCR) in patients with recurrent advanced epithelial ovarian cancer. METHODS: From Jan. 1986 to Dec. 1997, 60 women with recurrent advanced epithelial ovarian cancer treated with SCR were retrospectively reviewed. Survival curves were computed using the Kaplan-Meier method with differences in survival estimated by log-rank test. Independent prognostic factors were identified by Cox's stepwise regression, and the affecting factors of SCR evaluated by Logistic stepwise regression. RESULTS: Of the 60 patients, 23 (38.3%) were cytoreduced to small macroscopic residual (</= 1 cm) and 37 retained larger residual, with an estimated median survival of 19 months and 8 months respectively. Multivariate analysis revealed that residual disease (P = 0.0041) after SCR, as well as refractory ascites (P = 0.0191) and progression-free interval (P = 0.0116), were independent factors of survival. Refractory ascites (relative risk = 20.36, P = 0.0072) and residual disease after primary surgery (relative risk = 5.16, P = 0.0096) were factors affecting SCR. CONCLUSION: Secondary cytoreductive surgery is definitely effective in the treatment of recurrent advanced epithelial ovarian carcinoma, particularly in those who have received primary optimal cytoreduction with a progression-free interval > 12 months and without refractory ascites.

Adult↗

PubMed2002

[Factors affecting disease recurrence and the role of secondary therapies in the management for patients with recurrent ovarian carcinoma].

OBJECTIVE: To identify variants affecting disease recurrence and clarify the role of re-debulking surgery and second-line chemotherapy in the management of recurrent advanced epithelial ovarian cancer (AEOC). METHODS: One hundred and sixty-seven patients with recurrent AEOC treated in our hospital between Jan. 1986 and Dec. 1997 were retrospectively reviewed. Survival was calculated by Kaplan-Meier method with difference in survival estimated by Log-rank test. Independent prognostic factors were identified by the COX stepwise regression model, and variants associated with disease recurrence were found by logistic stepwise regression methods. RESULTS: The median age was 51 (range 26-71) years. Sixty patients underwent re-debulking surgery, 23 of them with residual disease </= 1 cm. There was a significant difference in survival between optimal and sub-optimal groups, with an estimated median survival of 20 and 10 months, respectively (chi(2) = 9.42, P = 0.021). When patients with sub-optimal surgical results were compared with those who had chemotherapy alone, there was a significant difference in median survival, 10 vs. 13 months (chi(2) = 4.38, P = 0.036 4). Age of the patients, refractory ascites, second-line chemotherapy, and residual disease after primary surgery were independent prognostic factors of survival identified by COX regression analysis. Logistic stepwise regression analysis revealed that age, platinum-based chemotherapy, neoadjuvant chemotherapy, and the size of residual disease after primary surgical cytoreduction were factors affecting progression-free interval. CONCLUSIONS: The age at diagnosis, residual disease, first-line chemotherapy, and neoadjuvant chemotherapy are factors affecting disease recurrence. Patients received second-line chemotherapy and with residual disease </= 1 cm after secondary surgery experience a better prognosis than those without receiving second-line chemotherapy or with residual disease > 1 cm after secondary cytoreduction.

Adult↗