Biomedical subjects

Zhenyu Zhang

Publications and source records attributed to Zhenyu Zhang.

At least 19 recordsLinked to original sources

PubMed2026

Direct and spillover hospitalisation patterns during climate hazards across regions of different health-system resilience levels in China: a nationwide retrospective analysis.

BACKGROUND: Health-system resilience serves as a key contributor in mitigating adverse health impacts during climate hazards. However, quantitative insights into resilience-associated health-care utilisation patterns and targeted adaptation policies remain scarce. We aimed to capture the spatiotemporal health impacts in disaster-exposed counties and their neighbouring counties in China during storms, floods, tropical cyclones, and blizzards or winter storms; understand the association between health-system resilience metrics and hazard-attributable hospitalisations; and develop evidence-based adaptation policies towards climate extremes. METHODS: In this retrospective, observational analysis of county-level aggregated hospitalisation data, we used a propensity score matching-difference-in-differences framework to assess the spatiotemporal changes of nine types of disease-specific hospitalisations in both disaster-exposed and neighbouring regions during storms, floods, tropical cyclones, and blizzards in China. We quantified the relative importance and health gains of health-system metrics during such hazards through random forest approach with interpretable partial dependence plots to derive evidence-based adaptation recommendations. FINDINGS: We included hospitalisation data from Jan 1, 2016 to Dec 31, 2023. In this period, 3241 county-hazard event combinations and 41 747 482 hospitalisations were recorded across 955 Chinese counties. The disaster-exposed regions experienced an initial decline in hospitalisation rates, followed by admission surges after disasters. For example, infectious disease admissions decreased by 11·92% (95% CI -10·53 to -13·31) during the flood-active period but increased by 7·68% (6·46-8·91) after 1-2 weeks of floods. Neighbouring zones were also affected through spillover effects, with infectious disease admissions increasing by 3·18% (1·76-4·61) after 1-2 weeks of the floods. Cardiovascular disease, injuries, infectious, respiratory, and mental disorders were more sensitive across all regions. Particularly for disaster-exposed counties, cardiovascular hospitalisations increased by 14·31% (7·34-21·29) during the tropical cyclone-active period. Notably, compared with low-resilience counties, high-resilience counties were associated with 19·48-30·03% smaller hazard-related relative changes in hospitalisation rates during the hazard-active period and 27·07-31·08% smaller hazard-related relative changes in hospitalisation rates in post-hazard periods. For instance, during the storm-active period, the increase in respiratory hospitalisations was 7·21% (0·67-13·75) in high-resilience counties versus 12·13% (5·20-19·05) in low-resilience counties. Health workforce (relative importance 14·58% during the hazard-active period and 13·80% during the post-hazard period) and service delivery (14·10% during the hazard-active period and 14·17% during the post-hazard period) were identified as key contributors of health-system resilience. Empirical synergistic effects were observed when combining interventions during the post-hazard period, with the combined effect of service delivery (individual contribution 8%) and workforce (individual contribution 4%) exceeding the sum of their individual contributions (16% reduction in cumulative excess admissions) by 33%. INTERPRETATION: Climate hazards are associated with substantial changes in hospitalisation rates in both disaster-exposed and neighbouring regions. Health-system resilience is essential in addressing disaster-health challenges. Targeted adaptation interventions should be context-appropriate and threshold-aware, thereby maximising the public health benefits relative to resilience-oriented investments in health systems. FUNDING: Gates Foundation and the National Natural Science Foundation of China.

Journal Article↗

PubMed2026

TMEM33 regulates the proliferation and migration of lung adenocarcinoma by promoting the PI3K/AKT/mTOR signaling pathway.

Lung adenocarcinoma is a common type of lung cancer with high incidence and mortality rates. TMEM33, a tumor-associated protein, has not been fully elucidated in lung adenocarcinoma. To explore the expression of TMEM33 in lung adenocarcinoma, its impact on tumor progression, and its role in the PI3K/AKT/mTOR signaling pathway. Key genes associated with lung adenocarcinoma were screened using the Gene Expression Omnibus (GEO) dataset GSE140797 in combination with a weighted correlation network analysis (WGCNA). Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed on these key genes. TMEM33 expression in Lung adenocarcinoma patients was validated using data from the TCGA database. The directly interactive molecules were screened through a bioinformatics method. Cellular assays (Western Blot, CCK8, colony formation, scratch assay, Trans well assay) and a nude mouse model were used to investigate the effects of TMEM33 on cell proliferation, migration, and tumor growth. TMEM33 is highly expressed in lung adenocarcinoma tissues (P < 0.05) and associated with poor prognosis. Overexpression of TMEM33 promotes cell proliferation and migration, and activates the PI3K/AKT/mTOR signaling pathway (P < 0.01). In the nude mouse model, TMEM33 overexpression increases tumor volume (P < 0.001), and PI3K/AKT pathway inhibition suppresses these effects (P < 0.05, P < 0.01). TMEM33 acts as an oncogene in lung adenocarcinoma by activating the PI3K/AKT/mTOR pathway, providing new therapeutic targets.

Cell migration↗

PubMed2026

Comprehensive characterization of MET exon 14 skipping mutations in non-small cell lung cancer.

BACKGROUND: MET exon 14 skipping mutation (METΔex14) is a key driver event in non-small cell lung cancer (NSCLC) and can emerge as an acquired drug resistance mechanism to MET, EGFR or ALK inhibitors. The clinical and genomic features of METΔex14 in NSCLC require further characterization. METHODS: Our study included a total of 585 patients with METΔex14 + NSCLC, comprising 556 baseline samples, 53 samples from patients exhibiting resistance to MET inhibitors, and 16 samples from patients resistant to EGFR/ALK inhibitors. Genomic data from targeted next-generation sequencing (NGS) of tissue and/or plasma samples using GeneseeqPrime™ (a 425 pan-cancer gene panel) were analyzed. RESULTS: Overall, METΔex14 exhibited a prevalence of 1.02% (n = 585) in the screened NSCLC population, with a higher incidence in patients with a sarcomatoid histology. METΔex14 was predominantly detected at the splice donor site, though the non-coding region adjacent to the splice acceptor site contributed considerably to the complexity of METΔex14. Common concurrent alterations identified at baseline included those in TP53 (40.8%), CDK4 (16%) and EGFR (12.4%). Concurrent MET amplification and cell cycle pathway mutations were both associated with worse outcomes in patients treated with crizotinib, with significant co-occurrences observed also among these concurrent genomic variations. In addition, increased chromosomal instability and intra-tumoral heterogeneity correlated with a poorer response to crizotinib. Mechanisms of acquired resistance to MET inhibitors were primarily attributed to on-target MET D1228X/Y1230X mutations or off-target alterations within genes in the RTK/RAS/MAPK and PI3K/AKT/mTOR pathways. Intriguingly, our exploratory analysis also identified the FGFR3::TACC3 fusion as a potential resistance mechanism to savolitinib. Moreover, METΔex14 was identified in 16 patients following progression on EGFR and ALK inhibitors, highlighting the need for developing tailored therapeutic strategies to overcome resistance. CONCLUSIONS: This study provides a comprehensive characterization of METΔex14 in NSCLC, revealing its dual role as a primary driver of oncogenesis and a potential resistance mechanism to EGFR/ALK inhibitors. The identification of concurrent genetic alterations and potential resistance mechanisms enhances our molecular understanding of treatment responses. These findings highlight the need for further investigation into targeted therapies that consider the genomic complexity of METΔex14 to improve treatment efficacy and patient outcomes.

Humans↗

PubMed2025

Multi-omics reveals an ecdysone-activated Eip75B-FABP signaling axis coordinating nutrient metabolism for development in Hermetia illucens.

INTRODUCTION: Efficient nutrient storage is essential for insect development and energy homeostasis; however, the mechanisms coordinating nutrient allocation during ontogeny are not well understood. Elucidating these systems may yield valuable insights to insect metabolic adaptation. OBJECTIVES: This study aimed to identify regulatory modules governing nutrient metabolism in insects, focusing on hormonal and metabolic interplay. METHODS: Multi-omics profiling (proteomics, phosphoproteomics, and transcriptomics) was conducted throughout the life cycle, from egg to adult, to identify metabolic regulators. RNAi was utilized for gene knockdown, followed by qRT-PCR and mitochondrial DNA quantification to evaluate knockdown efficiency and its metabolic implications. Assessments of nutrient metabolism were performed using assays for triglycerides, crude protein, and fatty acid synthase. EMSA and BODIPY staining examined transcriptional regulation and lipid droplet dynamics. RESULTS: Utilizing an integrative multi-omics approach, this study elucidates the temporal metabolic regulators in insects. A conserved regulatory module was identified in which the PPAR homolog, ecdysone-induced protein 75B (Eip75B), functions as a transcriptional activator of fatty acid binding protein (FABP), sustaining lipid metabolic homeostasis during the larval stage. PPARγ modulators (rosiglitazone and GW9662) alter lipid accumulation, along with the expression of Eip75B and FABP, which was measured by qRT-PCR. Furthermore, the deficiency of FABP may reprogram metabolic pathways by inhibiting lipid storage and promoting mitochondrial β-oxidation, as supported by increased mitochondrial DNA copy number, as well as enhancing protein synthesis. This metabolic change could be modulated by ecdysone signaling, as hormonal supplementation effectively rescued the lipid loss phenotype. Our results establish the ecdysone-Eip75B-FABP signaling axis as a central regulatory module that integrates hormonal and nutrient-sensing signals to control insect nutritional metabolism. CONCLUSION: The ecdysone-Eip75B-FABP axis integrates hormonal and nutrient signals to regulate metabolic plasticity, underscoring a universal strategy for developmental energy allocation. The data also offer potential implications for research on metabolic disorders and bioenergy applications.

Animals↗

PubMed2006

Generalized electron counting in determination of metal-induced reconstruction of compound semiconductor surfaces.

Based on theoretical analysis, first-principles calculations, and experimental observations, we establish a generic guiding principle, embodied in generalized electron counting (GEC), that governs the surface reconstruction of compound semiconductors induced by different metal adsorbates. Within the GEC model, the adsorbates serve as an electron bath, donating or accepting the right number of electrons as the host surface chooses a specific reconstruction that obeys the classic electron-counting model. The predictive power of the GEC model is illustrated for a wide range of metal adsorbates.

Journal Article↗

PubMed2006

One-dimensional arrays of nanoshell dimers for single molecule spectroscopy via surface-enhanced Raman scattering.

The optical properties of one-dimensional arrays of metal nanoshell dimers are studied systematically using the T-matrix method based on Mie theory, within the context of surface enhanced Raman scattering (SERS). It is shown that the local electromagnetic enhancement can be as high as approximately 4.5 x 10(13) for nanoshell dimer arrays with optimal geometry, and sensitive tunability in the resonant frequency can be gained by varying the geometrical parameters, making such structures appealing templates for SERS measurements with single molecule sensitivity. The extraordinarily high enhancement is attributed to a collective photonic effect constructively superposed onto the intrinsic enhancement associated with an isolated nanoshell dimer.

Journal Article↗

PubMed2006

Tuning solid surfaces from hydrophobic to superhydrophilic by submonolayer surface modification.

Molecular-scale understanding and manipulation of the wetting behavior of water on solids remains a fundamental challenge. Using diamond as a model system, we show that the naturally hydrophobic behavior of a hydrogen-terminated C(111) surface can be manipulated by replacing the H termination with a monolayer of adsorbate. In particular, a mixed monolayer of 1/3 Na and 2/3 F atoms leads to superhydrophilic behavior, as shown by first-principles calculations. The physical origin of the superhydrophilic behavior is attributed to the ionic nature of the Na adatoms, which mediate the right degree of binding strength between water molecules and the substrate.

Journal Article↗

PubMed2006

Chemical contribution to surface-enhanced Raman scattering.

We present a new mechanism for the chemical contribution to surface-enhanced Raman scattering (SERS). The theory considers the modulation of the polarizability of a metal nanocluster or a flat metal surface by the vibrational motion of an adsorbed molecule. The modulated polarization of the substrate coupled with the incident light will contribute to the Raman scattering enhancement. We show that for a metal cluster and for a flat metal surface this new chemical contribution may enhance the Raman scattering intensity by a factor of approximately 102 and approximately 104, respectively. The new SERS process is determined by the electric field parallel to the surface of the metal substrate at the molecular binding site.

Journal Article↗

PubMed2006

RETRACTED: Desorption of H from Si(111) by resonant excitation of the Si-H vibrational stretch mode.

Past efforts to achieve selective bond scission by vibrational excitation have been thwarted by energy thermalization. Here we report resonant photodesorption of hydrogen from a Si(111) surface using tunable infrared radiation. The wavelength dependence of the desorption yield peaks at 0.26 electron volt: the energy of the Si-H vibrational stretch mode. The desorption yield is quadratic in the infrared intensity. A strong H/D isotope effect rules out thermal desorption mechanisms, and electronic effects are not applicable in this low-energy regime. A molecular mechanism accounting for the desorption event remains elusive.

Journal Article↗

PubMed2006

Localization of subunit C (Vma5p) in the yeast vacuolar ATPase by immuno electron microscopy.

Vacuolar ATPases (V1V0 -ATPases) function in proton translocation across lipid membranes of subcellular compartments. We have used antibody labeling and electron microscopy to define the position of subunit C in the vacuolar ATPase from yeast. The data show that subunit C is binding at the interface of the ATPase and proton channel, opposite from another stalk density previously identified as subunit H [Wilkens S., Inoue T., and Forgac M. (2004) Three-dimensional structure of the vacuolar ATPase - Localization of subunit H by difference imaging and chemical cross-linking. J. Biol. Chem. 279, 41942-41949]. A picture of the vacuolar ATPase stalk domain is emerging in which subunits C and H are positioned to play a role in reversible enzyme dissociation and activity silencing.

Antibodies, Monoclonal↗

PubMed2005

Multiple bosonic mode coupling in the electron self-energy of (La2-xSrx)CuO4.

High resolution angle-resolved photoemission spectroscopy data along the (0,0)-(pi,pi) nodal direction with significantly improved statistics reveal fine structure in the electron self-energy of the underdoped (La2-xSrx)CuO4 samples in the normal state. Fine structure at energies of (40-46) meV and (58-63) meV, and possible fine structure at energies of (23-29) meV and (75-85) meV, have been identified. These observations indicate that, in (La2-xSrx)CuO4, more than one bosonic modes are involved in the coupling with electrons.

Journal Article↗

PubMed2005

Persistent step-flow growth of strained films on vicinal substrates.

We propose a model of persistent step flow, emphasizing dominant kinetic processes and strain effects. Within this model, we construct a morphological phase diagram, delineating a regime of step flow from regimes of step bunching and island formation. In particular, we predict the existence of concurrent step bunching and island formation, a new growth mode that competes with step flow for phase space, and show that the deposition flux and temperature must be chosen within a window in order to achieve persistent step flow. The model rationalizes the diverse growth modes observed in pulsed laser deposition of SrRuO3 on SrTiO3.

Journal Article↗

PubMed2005

Kinetic pathway for the formation of fe nanowires on stepped Cu111 surfaces.

We report the discovery of a novel kinetic pathway for the formation of one-dimensional Fe nanowires of single atom width on stepped Cu(111) surfaces. This pathway, identified through extensive total-energy calculations within density functional theory, establishes that the stable structure involves a row of Fe atoms on the upper edge of a step. The formation of the surface wire is preceded by facile incorporation of an initial row of Fe atoms into the surface layer at one lateral lattice constant away from the step edge, which then acts as an attractor for the second exposed row of atoms. The resulting wire structure provides a natural interpretation of existing experimental results. We also explore the applicability of this mechanism in the formation of other related systems.

Journal Article↗

PubMed2005

Initial stages of Ti growth on diamond (100) surfaces: from single adatom diffusion to quantum wire formation.

Using first-principles total energy calculations within density functional theory, we investigate the energetics, kinetics, and transport properties of Ti on clean and hydrogen-terminated diamond (100)-2x1 surfaces at increasing Ti coverages. On a clean surface, an isolated Ti adatom prefers to adsorb on top of a C-C dimer row, and also diffuses faster along the dimer row direction. As the Ti coverage increases, the preferred adsorption site converts from an atop site to a site located between the dimer rows. Passivation of the surface at the monohydride coverage not only greatly enhances the Ti mobility, but also weakens the diffusion isotropy. Based on these energetic and kinetic characteristics, we propose a viable approach to fabricate ideal Ti quantum wires on hydrogen-terminated diamond substrates.

Journal Article↗

PubMed2005

A structural model of the vacuolar ATPase from transmission electron microscopy.

Vacuolar ATPases (V-ATPases) are large, membrane bound, multisubunit protein complexes which function as ATP hydrolysis driven proton pumps. V-ATPases and related enzymes are found in the endomembrane system of eukaryotic organsims, the plasma membrane of specialized cells in higher eukaryotes, and the plasma membrane of prokaryotes. The proton pumping action of the vacuolar ATPase is involved in a variety of vital intra- and inter-cellular processes such as receptor mediated endocytosis, protein trafficking, active transport of metabolites, homeostasis and neurotransmitter release. This review summarizes recent progress in the structure determination of the vacuolar ATPase focusing on studies by transmission electron microscopy. A model of the subunit architecture of the vacuolar ATPase is presented which is based on the electron microscopic images and the available information from genetic, biochemical and biophysical experiments.

Animals↗

PubMed2005

Quantum growth of magnetic nanoplatelets of Co on Si with high blocking temperature.

Self-organized Co nanoplatelets with a singular height, quantized lateral sizes, and unique shape and orientation have been fabricated on a template consisting of ordered Al nanocluster arrays on Si(111)-7 x 7 surfaces. Despite their small volume (a few nm(3)), these nanomagnets exhibit an unusually high blocking temperature (>100 K). The perpendicular direction for easy magnetization, the high blocking temperature, the size tunability, and the epitaxial growth on Si substrates make these nanomagnets important for applications in information technology.

Journal Article↗

PubMed2004

"Lagrange functions": a family of powerful basis sets for real-space order-N electronic structure calculations.

Plane waves have unparalleled simplicity and systematic convergence by a single monotonic parameter, the energy cutoff, but they are limited to speriodic systems and require Fourier transforms that scale as N(2)logN, where N is the number of atoms. Real-space methods for order-N scaling are computationally complex and convergence depends on several variables. Here we introduce and demonstrate "Lagrange functions" as a family of analytical, complete, and orthonormal basis sets that are suitable for efficient, accurate, real-space, order-N electronic structure calculations. Convergence is controlled by a single monotonic parameter, the dimension of the basis set, and computational complexity is lower than that of plane waves.

Journal Article↗

PubMed2004

Contrasting growth modes of Mn on Ge(100) and Ge(111) surfaces: subsurface segregation versus intermixing.

Based on first-principles total energy calculations within density functional theory, we show that a low dose of Mn on Ge(100) initiates in a novel subsurface growth mode, characterized by easy access to, and strong preference for, interstitial sites located between the two topmost Ge layers. Strikingly, such a "subsurfactant action" is preserved even during epitaxial growth of additional Ge layers, analogous to the well-known phenomenon of surfactant action. In contrast, along the [111] orientation, Mn can easily diffuse into the bulk via interstitial sites. These results are discussed within the context of dopant control in dilute magnetic semiconductors.

Journal Article↗