Polysaccharides from the root of Angelica sinensis protect bone marrow and gastrointestinal tissues against the cytotoxicity of cyclophosphamide in mice

Cyclophosphamide (CY) is a cytostatic agent that produces systemic toxicity especially on cells with high proliferative capacity, while polysaccharides from Angelica sinensis (AP) have been shown to increase the turnover of gastrointestinal mucosal and hemopoietic stem cells. It is not known whether AP has an effect on CY-induced cytotoxicity on bone marrow and gastrointestinal tract. In this study, we assessed the protective actions of AP on CY-induced leukopenia and proliferative arrest in the gastroduodenal mucosa in mice. Subcutaneous injection of CY (200 mg/kg) provoked dramatic decrease in white blood cell (WBC) count and number of blood vessels and proliferating cells in both the gastric and duodenal mucosae. Subcutaneous injection of AP significantly promoted the recovery from leukopenia and increased number of blood vessels and proliferating cells in both the gastric and duodenal tissues. Western blotting revealed that CY significantly down-regulated the protein expression of vascular endothelial growth factor (VEGF), c-Myc and ornithine decarboxylase (ODC) in gastric mucosae but had no effect on epidermal growth factor (EGF) expression. AP also reversed the dampening effect of CY on VEGF expression in the gastric mucosa. These data suggest that AP is a cytoprotective agent which can protect against the cytotoxicity of CY on hematopoietic and gastrointestinal tissues when the polysaccharide is co-administered with CY in cancer patients during treatment regimen.published_or_final_versio

Anti-tumorigenic and Pro-apoptotic effects of CKBM on gastric cancer growth in nude mice

Natural botanical products can be integrated with western medicine to optimize the treatment outcome, increase immune function and minimize the side effects from western drug treatment. CKBM is a combination of herbs and yeasts formulated based on traditional Chinese medicinal principles. Previous study has demonstrated that CKBM is capable of improving immune responsiveness through the induction of cytokine mediators, such as TNF-α and IL-6. In this study, we aimed to investigate the effect of this immunomodulatory drug on gastric cancer growth using a human xenograft model. Gastric cancer tissues were implanted subcutaneously into athymic nude mice followed by a 14-day or 28-day of CKBM treatment. Results showed that higher doses of CKBM (0.4 or 0.8 ml/mouse/day) produced a dose-dependent inhibitory effect on gastric tumor growth after 28-day drug treatment. This was associated with a decrease of cellular proliferation by 30% with concomitant increase in apoptosis by 97% in gastric tumor cells when compared with the control group. In contrast, CKBM showed no effect on angiogenesis in gastric tumors. This study demonstrates the anti-tumorigenic action of CKBM on gastric cancer probably via inhibition of cell proliferation and induction of apoptosis, and provides future potential targets of this drug candidate on cancer therapy.published_or_final_versio

N‑Linked Glycosylation Prevents Deamidation of Glycopeptide and Glycoprotein

Deamidation has been recognized as a common spontaneous pathway of protein degradation and a prevalent concern in the pharmaceutical industry; deamidation caused the reduction of protein/peptide drug efficacy and shelf life in several cases. More importantly, deamidation of physiological proteins is related to several human diseases and considered a timer for the diseases. N-linked glycosylation has a variety of significant biological functions, and it interestingly occurs right on the deamidation site-asparagine. It has been perceived that N-glycosylation could prevent deamidation, but experimental support is still lacking for clearly understanding the role of N-glycosylation on deamidation. Our results presented that deamidation is prevented by naturally occurring N-linked glycosylation. Glycopeptides and corresponding nonglycosylated peptides were used to compare their deamidation rates. All the nonglycosylated peptides have different half-lives ranging from one to 20 days, for the corresponding glycosylated peptides; all the results showed that the deamidation reaction was significantly reduced by the introduction of N-linked glycosylation. A glycoprotein, RNase B, also showed a significantly elongated deamidation half-life compared to nonglycosylated protein RNase A. At last, N-linked glycosylation on INGAP-P, a therapeutic peptide, increased the deamidation half-life of INGAP-P as well as its therapeutic potency

Long-range transfer of electron-phonon coupling in oxide superlattices

The electron-phonon interaction is of central importance for the electrical and thermal properties of solids, and its influence on superconductivity, colossal magnetoresistance, and other many-body phenomena in correlated-electron materials is currently the subject of intense research. However, the non-local nature of the interactions between valence electrons and lattice ions, often compounded by a plethora of vibrational modes, present formidable challenges for attempts to experimentally control and theoretically describe the physical properties of complex materials. Here we report a Raman scattering study of the lattice dynamics in superlattices of the high-temperature superconductor $\bf YBa_2 Cu_3 O_7$ and the colossal-magnetoresistance compound $\bf La_{2/3}Ca_{1/3}MnO_{3}$ that suggests a new approach to this problem. We find that a rotational mode of the MnO$_6$ octahedra in $\bf La_{2/3}Ca_{1/3}MnO_{3}$ experiences pronounced superconductivity-induced lineshape anomalies, which scale linearly with the thickness of the $\bf YBa_2 Cu_3 O_7$ layers over a remarkably long range of several tens of nanometers. The transfer of the electron-phonon coupling between superlattice layers can be understood as a consequence of long-range Coulomb forces in conjunction with an orbital reconstruction at the interface. The superlattice geometry thus provides new opportunities for controlled modification of the electron-phonon interaction in complex materials.Comment: 13 pages, 4 figures. Revised version to be published in Nature Material

Risk Model-Based Lung Cancer Screening and Racial and Ethnic Disparities in the US

Importance The revised 2021 US Preventive Services Task Force (USPSTF) guidelines for lung cancer screening have been shown to reduce disparities in screening eligibility and performance between African American and White individuals vs the 2013 guidelines. However, potential disparities across other racial and ethnic groups in the US remain unknown. Risk model–based screening may reduce racial and ethnic disparities and improve screening performance, but neither validation of key risk prediction models nor their screening performance has been examined by race and ethnicity.Objective To validate and recalibrate the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial 2012 (PLCOm2012) model—a well-established risk prediction model based on a predominantly White population—across races and ethnicities in the US and evaluate racial and ethnic disparities and screening performance through risk-based screening using PLCOm2012 vs the USPSTF 2021 criteria.Design, Setting, and Participants In a population-based cohort design, the Multiethnic Cohort Study enrolled participants in 1993-1996, followed up through December 31, 2018. Data analysis was conducted from April 1, 2022, to May 19. 2023. A total of 105 261 adults with a smoking history were included.Exposures The 6-year lung cancer risk was calculated through recalibrated PLCOm2012 (ie, PLCOm2012-Update) and screening eligibility based on a 6-year risk threshold greater than or equal to 1.3%, yielding similar eligibility as the USPSTF 2021 guidelines.Outcomes Predictive accuracy, screening eligibility-incidence (E-I) ratio (ie, ratio of the number of eligible to incident cases), and screening performance (sensitivity, specificity, and number needed to screen to detect 1 lung cancer).Results Of 105 261 participants (60 011 [57.0%] men; mean [SD] age, 59.8 [8.7] years), consisting of 19 258 (18.3%) African American, 27 227 (25.9%) Japanese American, 21 383 (20.3%) Latino, 8368 (7.9%) Native Hawaiian/Other Pacific Islander, and 29 025 (27.6%) White individuals, 1464 (1.4%) developed lung cancer within 6 years from enrollment. The PLCOm2012-Update showed good predictive accuracy across races and ethnicities (area under the curve, 0.72-0.82). The USPSTF 2021 criteria yielded a large disparity among African American individuals, whose E-I ratio was 53% lower vs White individuals (E-I ratio: 9.5 vs 20.3; P < .001). Under the risk-based screening (PLCOm2012-Update 6-year risk ≥1.3%), the disparity between African American and White individuals was substantially reduced (E-I ratio: 15.9 vs 18.4; P < .001), with minimal disparities observed in persons of other minoritized groups, including Japanese American, Latino, and Native Hawaiian/Other Pacific Islander. Risk-based screening yielded superior overall and race and ethnicity–specific performance to the USPSTF 2021 criteria, with higher overall sensitivity (67.2% vs 57.7%) and lower number needed to screen (26 vs 30) at similar specificity (76.6%).Conclusions The findings of this cohort study suggest that risk-based lung cancer screening can reduce racial and ethnic disparities and improve screening performance across races and ethnicities vs the USPSTF 2021 criteria

Mild Transient Hypercapnia as a Novel Fear Conditioning Stimulus Allowing Re-Exposure during Sleep

Introduction:Studies suggest that sleep plays a role in traumatic memories and that treatment of sleep disorders may help alleviate symptoms of posttraumatic stress disorder. Fear-conditioning paradigms in rodents are used to investigate causal mechanisms of fear acquisition and the relationship between sleep and posttraumatic behaviors. We developed a novel conditioning stimulus (CS) that evoked fear and was subsequently used to study re-exposure to the CS during sleep.Methods:Experiment 1 assessed physiological responses to a conditioned stimulus (mild transient hypercapnia, mtHC; 3.0% CO2; n = 17)+footshock for the purpose of establishing a novel CS in male FVB/J mice. Responses to the novel CS were compared to tone+footshock (n = 18) and control groups of tone alone (n = 17) and mild transient hypercapnia alone (n = 10). A second proof of principle experiment re-exposed animals during sleep to mild transient hypercapnia or air (control) to study sleep processes related to the CS.Results:Footshock elicited a response of acute tachycardia (30-40 bpm) and increased plasma epinephrine. When tone predicted footshock it elicited mild hypertension (1-2 mmHg) and a three-fold increase in plasma epinephrine. When mtHC predicted footshock it also induced mild hypertension, but additionally elicited a conditioned bradycardia and a smaller increase in plasma epinephrine. The overall mean 24 hour sleep-wake profile was unaffected immediately after fear conditioning.Discussion:Our study demonstrates the efficacy of mtHC as a conditioning stimulus that is perceptible but innocuous (relative to tone) and applicable during sleep. This novel model will allow future studies to explore sleep-dependent mechanisms underlying maladaptive fear responses, as well as elucidate the moderators of the relationship between fear responses and sleep. © 2013 McDowell et al

Alpha-2-Macroglobulin Is Acutely Sensitive to Freezing and Lyophilization: Implications for Structural and Functional Studies.

Alpha-2-macroglobulin is an abundant secreted protein that is of particular interest because of its diverse ligand binding profile and multifunctional nature, which includes roles as a protease inhibitor and as a molecular chaperone. The activities of alpha-2-macroglobulin are typically dependent on whether its conformation is native or transformed (i.e. adopts a more compact conformation after interactions with proteases or small nucleophiles), and are also influenced by dissociation of the native alpha-2-macroglobulin tetramer into stable dimers. Alpha-2-macroglobulin is predominately present as the native tetramer in vivo; once purified from human blood plasma, however, alpha-2-macroglobulin can undergo a number of conformational changes during storage, including transformation, aggregation or dissociation. We demonstrate that, particularly in the presence of sodium chloride or amine containing compounds, freezing and/or lyophilization of alpha-2-macroglobulin induces conformational changes with functional consequences. These conformational changes in alpha-2-macroglobulin are not always detected by standard native polyacrylamide gel electrophoresis, but can be measured using bisANS fluorescence assays. Increased surface hydrophobicity of alpha-2-macroglobulin, as assessed by bisANS fluorescence measurements, is accompanied by (i) reduced trypsin binding activity, (ii) increased chaperone activity, and (iii) increased binding to the surfaces of SH-SY5Y neurons, in part, via lipoprotein receptors. We show that sucrose (but not glycine) effectively protects native alpha-2-macroglobulin from denaturation during freezing and/or lyophilization, thereby providing a reproducible method for the handling and long-term storage of this protein.Early Career Fellowship from the National Health and Medical Research Council GNT1012521(A.R.W.); Wellcome Trust Programme Grant (J.R.K., C.M.D.) 094425/Z/10/Z; Samsung GRO Grant (M.R.W.)This is the final version of the article. It first appeared from PLoS via http://dx.doi.org/10.1371/journal.pone.013003

Azimuthal anisotropy and correlations at large transverse momenta in p+pp+p and Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV

Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at $\sqrt{s_{_{NN}}}$= 200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in $p+p$ at the same energy. Elliptic anisotropy, $v_2$, is found to reach its maximum at $p_t \sim 3$ GeV/c, then decrease slowly and remain significant up to $p_t\approx 7$ -- 10 GeV/c. Stronger suppression is found in the back-to-back high-$p_t$ particle correlations for particles emitted out-of-plane compared to those emitted in-plane. The centrality dependence of $v_2$ at intermediate $p_t$ is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004