[Efficiency and safety of peptide receptor radionuclide therapy in the treatment of metastatic neuroendocrine tumors]

The clinical data of 14 patients with neuroendocrine tumors who received Peptide Receptor Radionuclide Therapy (PRRT) from December 2018 to May 2021 were retrospectively analyzed. Among them, 2 patients demonstrated proprogressive disease, 2 patients had partial response, and 10 patients had stable disease. Grade 1-2 myelosuppression occurred in 5 patients. and 1 patient became grade 3 myelosuppression，which recovered to grade 2 after symptomatic treatment. No grade 2 or higher treatment-related renal toxicity was observed in any of the patients. PRRT is efficacy and no significant side effects for unresectable metastatic neuroendocrine tumors.

[Analysis of HIV-1 genetic subtype and pretreatment drug resistance among men who have sex with men infected with HIV-1 from 19 cities of 6 provinces in China]

Objective: To investigate the distribution of HIV-1 genetic subtypes and pretreatment drug resistance (PDR) among men who have sex with men (MSM) from 19 cities of 6 provinces in China. Methods: From April to November 2019, 574 plasma samples of ART-naive HIV-1 infected MSM were collected from 19 cities in Hebei, Shandong, Jiangsu, Zhejiang, Fujian, and Guangdong provinces, total ribonucleic acid (RNA) was extracted and amplified the HIV-1 pol gene region by nested polymerase chain reaction (PCR) after reverse transcription. Then sequences were used to construct a phylogenetic tree to determine genetic subtypes and submitted to the Stanford drug resistance database for drug resistance analysis. Results: A total of 479 samples were successfully amplified by PCR. The HIV-1 genetic subtypes included CRF01_AE, CRF07_BC, B, CRF55_01B, CRF59_01B, CRF65_cpx, CRF103_01B, CRF67_01B, CRF68_01B and unrecognized subtype, which accounted for 43.4%, 36.3%, 6.3%, 5.9%, 0.8%, 0.8%, 0.4%, 0.4%, 0.2% and 5.5%, respectively. The distribution of genetic subtypes among provinces is statistically different (χ²=44.141, P<0.001). The overall PDR rate was 4.6% (22/479), the drug resistance rate of non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, and protease inhibitors were 3.5% (17/479), 0.8% (4/479) and 0.2% (1/479), respectively. The PDR rate of recent infections was significantly higher than that of long-term infections (χ²=4.634, P=0.031). Conclusions: The HIV-1 genetic subtypes among MSM infected with HIV-1 from 19 cities of 6 provinces in China are diverse, and the distribution of subtypes is different among provinces. The overall PDR rate is low, while the PDR rate of recent infections was significantly higher than that of long-term infections, suggesting the surveillance of PDR in recent infections should be strengthened.

[Application of limiting antigen avidity enzyme immunoassay for estimating HIV-1 incidence in men who have sex with men]

Objective: To estimate the incidence of HIV-1 infection in men who have sex with men (MSM) in key areas of China through HIV-1 limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA), analyze the deviation from the actual results and identify influencing factors, and provided reference for improving the accuracy of estimation results. Methods: Based on the principle of the cohort randomized study design, 20 cities were selected in China based on population size and the number of HIV-positive MSM. The sample size was estimated to be 700 according to the HIV-1 infection rate in MSM. MSM mobile phone app. was used to establish a detection appointment and questionnaire system, and the baseline cross-sectional survey was conducted from April to November 2019. LAg-Avidity EIA was used to identify the recent infected samples. The incidence of HIV-1 infection was calculated and then adjusted based on the estimation formula designed by WHO. The influencing factors were identified by analyzing the sample collection and detection processes. Results: Among the 10 650 blood samples from the participants, 799 were HIV-positive in initial screening, in which 198 samples (24.78%) missed during confirmation test. Only 621 samples were received by the laboratory. After excluding misreported samples, 520 samples were qualified for testing. A total of 155 samples were eventually determined as recent infection through LAg-Avidity EIA; Based on the estimation formula , the incidence of HIV-1 infection in MSM in 20 cities was 4.06% (95%CI:3.27%-4.85%), it increased to 5.53% (95%CI: 4.45%-6.60%)after the adjusting for sample missing rate. When the sample missing rate and misreporting rate were both adjusted, the incidence of HIV-1 infection in the MSM increased to 5.66% (95%CI:4.67%-6.65%). The actual incidence of HIV-1 infection in MSM in the 20 cities might be between 4.06% and 5.66%. Conclusions: Sample missing and misreporting might cause the deviation of the estimation of HIV-1 infection incidence. It is important to ensure the sample source and the quality of sample collection and detection to reduce the deviation in the estimation of HIV-1 infection incidence.

Equine chorionic gonadotropin pretreatment 15 days before fixed-time artificial insemination improves the reproductive performance of replacement gilts

Fixed-time artificial insemination (FTAI) technology uses exogenous reproductive hormones to regulate the sexual cycle and ovulation of sows without oestrus identification, which improves the sow breeding utilisation rate, reduces the number of non-productive days, and elevates the efficiency of pig farm management. In this study, we aimed to optimise FTAI procedures. Healthy 190-day-old and about 90 kg Large White × Landrace crossing breed replacement gilts (n = 166) which were of unknown reproductive status were randomly selected and divided into three groups: a control group (n = 62), an eCG-15D group in which the gilts were pretreated with equine chorionic gonadotropin (eCG) injection 15 days before starting FTAI (n = 50), and an eCG-20D group pretreated with eCG injection 20 days before starting FTAI (n = 54). All three groups were then subjected to the same conventional FTAI procedure. Pigs were orally administered Altrenogest (ALT, 20 mg per pig per day) for 18 days and then 42 h after ALT feeding was stopped, they were injected with 1 000 IU eCG followed by 100 μg GnRH 80 h later. The gilts were inseminated for the first time 24 h after gonadotropin-releasing hormone (GnRH) injection and then again 16 h later. After 42 h of ALT feeding, gilts in the eCG-15D group displayed a higher follicular diameter until artificial insemination (AI) than those from the other groups (P < 0.05). In addition, the ovulation times were the most synchronised in the eCG-15D group, with 100% of the gilts ovulating before the second AI on day 25 of FTAI. Furthermore, the gilts in the eCG-15D group achieved the highest pregnancy rate (92%), farrowing rate (90%), total pigs born (11.59), and pigs born alive (11.18). Together, the findings of this study demonstrate that reproductive performance can be optimised by pretreating gilts with eCG 15 days before conventional FTAI.

Metabolomics Changes of Serum and Tissues in Mice Died of Acute Tetracaine Poisoning

Abstract

Objective To study the changes of metabolites in serum and tissues （kidney, liver and heart） of mice died of acute tetracaine poisoning by metabolomics, to search for potential biomarkers and related metabolic pathways, and to provide new ideas for the identification of cause of death and research on toxicological mechanism of acute tetracaine poisoning. Methods Forty ICR mice were randomly divided into control group and acute tetracaine poisoning death group. The model of death from acute poisoning was established by intraperitoneal injection of tetracaine, and the metabolic profile of serum and tissues of mice was obtained by ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry （UPLC-Orbitrap HRMS）. Multivariate statistical principal component analysis （PCA） and orthogonal partial least square-discriminant analysis （OPLS-DA） were used, combined with t-test and fold change to identify the differential metabolites associated with death from acute tetracaine poisoning. Results Compared with the control group, the metabolic profiles of serum and tissues in the mice from acute tetracaine poisoning death group were significantly different. Eleven differential metabolites were identified in serum, including xanthine, spermine, 3-hydroxybutylamine, etc.; twenty-five differential metabolites were identified in liver, including adenylate, adenosine, citric acid, etc.; twelve differential metabolites were identified in heart, including hypoxanthine, guanine, guanosine, etc; four differential metabolites were identified in kidney, including taurochenodeoxycholic acid, 11, 12-epoxyeicosatrienoic acid, dimethylethanolamine and indole. Acute tetracaine poisoning mainly affected purine metabolism, tricarboxylic acid cycle, as well as metabolism of alanine, aspartic acid and glutamic acid. Conclusion The differential metabolites in serum and tissues of mice died of acute tetracaine poisoning are expected to be candidate biomarkers for this cause of death. The results can provide research basis for the mechanism and identification of acute tetracaine poisoning.

Effect modification of the association between diurnal temperature range and hospitalisations for ischaemic stroke by temperature in Hefei, China

OBJECTIVES

Diurnal temperature range (DTR) is an important indicator of global climate change. Many epidemiological studies have reported the associations between high DTR and human health. This study investigated the association between DTR and hospitalisations for ischaemic stroke in Hefei, China.

STUDY DESIGN

This is an ecological study.

METHODS

Data of daily hospital admissions for ischaemic stroke and meteorological variables from 1 January 2009 to 31 December 2017 were collected in Hefei, China. A generalised additive model combined with distributed lag non-linear model was used to quantify the effects of DTR on ischaemic stroke. The interactive effect between DTR and temperature was explored with a non-parametric bivariate response surface model.

RESULTS

High DTR was associated with hospitalisations for ischaemic stroke. The adverse effect of extremely high DTR (99th percentile [17.1 °C]) occurred after 8 days (relative risk [RR] = 1.021, 95% confidence interval [CI] = 1.002, 1.041) and the maximum effect appeared after 12 days (RR = 1.029, 95% CI = 1.011, 1.046). The overall trend of the effect of DTR on ischaemic stroke was decreasing. In addition, there was a significant interactive effect of high DTR and low temperature on ischaemic stroke.

CONCLUSIONS

This study suggests that the impact of high DTR should be considered when formulating targeted measures to prevent ischaemic stroke, especially for those days with high DTR and low mean temperature.

Heterotrimeric G protein signalling in plant biotic and abiotic stress response

Heterotrimeric G proteins act as molecular switches to participate in transmitting various stimuli signals from outside of cells. G proteins have three subunits, Gα, Gβ and Gγ, which function mutually to modulate many biological processes in plants, including plant growth and development, as well as biotic and abiotic stress responses. In plants, the number of Gγ subunits is larger than that of the α and β subunits. Based on recent breakthroughs in studies of plant G protein signal perception, transduction and downstream effectors, this review summarizes and analyses the connections between different subunits and the interactions of G proteins with other signalling pathways, especially in plant biotic and abiotic stress responses. Based on current progress and unresolved questions in the field, we also suggest future research directions on G proteins in plants.

[HIV infection and related factors among men who have sex with men aged 50 and above]

Objectives: To explore the HIV prevalence and related factors among MSM aged 50 and above and provide evidence on the prevention and control of HIV/AIDS. Methods: Based on an MSM social application software Blued 7.1.6, we recruited participants through online convenience sampling to collect demographic variables, behavioral and self-reported HIV infection status, etc. Univariate χ2 test and multivariate logistic regression were used to analyze the related factors of self-reported HIV infection. Results: Self-reported HIV infection rate was 17.6%(126/714) among the participants. In multivariable analysis, participants who got divorced or widowed had a 2.07(95%CI: 1.34-3.21) times greater risk of self-reported HIV-positive than those who were married. Participants unaware of HIV-related knowledge showed a 1.92(95%CI:1.21-3.04) times greater risk of self-reported HIV-positive than those with better HIV-related knowledge. Participants who have ever been diagnosed with sexually transmitted disease (STD) showed a 3.17(95%CI:2.09-4.83) times greater risk of self-reported HIV-positive than those without STD infection history. Conclusion: Our findings indicated that the self-reported HIV infection rate was high among MSM aged 50 and above. Being divorced or widowed, being unaware of HIV-related knowledge and STD infection history was proved related with self-reported HIV infection.

[Exploration on contamination and transmission of SARS-CoV-2 in imported cold chain aquatic products]

Contaminations of SARS-CoV-2 have been found for many times in imported cold chain aquatic products and their packaging materials in China. The purpose of this paper is to analyze the contamination status, sources and transmission risks of SARS-CoV-2 in imported cold chain aquatic products, and try to put forward relevant suggestions and strategies in order to provide evidence for the prevention and control of SARS-CoV-2 infection.

Ethyl acetate fraction from Nymphaea hybrida Peck modulates inflammatory responses in LPS-stimulated RAW 264.7 cells and acute inflammation murine models

ETHNOPHARMACOLOGICAL RELEVANCE

Nymphaea hybrida Peck is used as a traditional medicinal herb for treating pain and inflammatory diseases, and known for its ornamental value and as a hot drink. However, the effects of N. hybrida polar fractions on lipopolysaccharide (LPS)-induced in vitro inflammation model and acute inflammation murine models have yet to be evaluated.

AIM OF THE STUDY

The aim of this study was to elucidate the anti-inflammatory effects of N. hybrida ethanol extract (NHE) and its polar fractions: petroleum ether (PE), methylene chloride (MC), ethyl acetate (EA), methanol (ME), and water (WA). The underlying molecular mechanisms of active fraction in LPS-stimulated RAW 264.7 murine macrophages were further investigated.

MATERIAL AND METHODS

Fractions with potential anti-inflammatory effects were screened using direct nitric oxide (NO) radical scavenging and cyclooxygenase (COX)-2 inhibition assays in vitro. The anti-inflammatory properties of potential fraction were evaluated in LPS-stimulated RAW264.7 cells, xylene-induced ear edema, carrageenan-induced paw edema and xylene-induced Evans blue exudation of acute inflammation murine models. The regulation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were investigated using western blotting and immunofluorescence.

RESULTS

Compared to other polar fractions, NHE-EA displayed higher phenol and flavonoid content, and exerted greater activity in direct NO radical scavenging and COX-2 inhibition assay in vitro. NHE-EA markedly decreased the levels of inflammatory mediators, NO and prostaglandin E₂ (PGE₂), by suppressing the over-expression of inducible nitric oxide synthase (iNOS) and COX-2 in LPS-stimulated RAW264.7 cells. The NHE-EA fraction dose-dependently alleviated over-elevation of LPS-associated intracellular calcium and decreased the abnormal secretion of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and interferon-γ (IFN-γ). The combination with NHE-EA effectively attenuated the activation and nuclear translocation of NF-κB p65, and the phosphorylation of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 kinases of MAPK pathways. NHE-EA could significantly ameliorate the degree of swelling of the mice ear and paw, the skin exudation of Evans blue and the excessive secretion of inflammatory cytokines.

CONCLUSION

Our results demonstrated that NHE-EA was the most active polar fraction of N. hybrida extracts. It inhibited the LPS-associated inflammatory response by blocking the activation of NF-κB and MAPKs pathways in RAW264.7 cells. It also effectively alleviated the inflammatory response of acute inflammation. These results indicated the role of NHE-EA as adjuvants and their potential role in alternative strategy for the treatment of inflammatory diseases.

Sevoflurane inhibits neuronal apoptosis and expressions of HIF-1 and HSP70 in brain tissues of rats with cerebral ischemia/reperfusion injury

OBJECTIVE

To observe the influences of sevoflurane on neuronal apoptosis and expressions of hypoxia-inducible factor 1 (HIF-1), and heat-shock protein 70 (HSP70) in brain tissues of rats with cerebral ischemia/reperfusion (I/R) injury.

MATERIALS AND METHODS

A total of 60 Sprague-Dawley rats were selected and divided into sham-operation group (Sham group, n=20), cerebral I/R model group (Model group, n=20), and 3% sevoflurane treatment group (Sevoflurane group, n=20). The rats in each group received neurological scoring, and the blood and brain tissues were collected to detect the concentrations of serum K+, Na+ and glucose (Glu). Enzyme-linked immunosorbent assay (ELISA) was adopted to measure the levels of inflammatory factors [tumor necrosis factor-β (TNF-β) and interleukin-6 (IL-6)] and oxidative stress [catalase (CAT), malondialdehyde (MDA) and superoxide dismutase (SOD)]. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was performed to determine the nerve cell apoptosis in the brain tissues. The gene and protein expressions of Caspase-3, HIF-1, and HSP70 in the brain tissues were measured via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) and Western blotting.

RESULTS

In Sevoflurane group, the content of serum Glu and Na+ was decreased markedly, that of K+ was increased notably, and the levels of TNF-β, IL-1 and IL-6 were lowered remarkably compared with those in Model group (p<0.05). Moreover, the neurological score was reduced evidently (p<0.05). Model group had significantly strengthened the activity of MDA and CAT and decreased SOD content, while Sevoflurane group exhibited the opposite results. TUNEL staining showed that there were distinctly more apoptotic cells that were dominated by glial cells in Model group and fewer apoptotic cells in Sevoflurane group. It was indicated in gene assay that the messenger ribonucleic acid (mRNA) expression levels of HIF-1, HSP70, and Caspase-3 in Model group were remarkably higher than those in Sham group and Sevoflurane group (p<0.05). According to the results of Western blotting, the protein expressions of HIF-1 and HSP70 in Sevoflurane group were markedly lower than those in Model group.

CONCLUSIONS

Sevoflurane can reduce the content of inflammatory factors, inhibit apoptosis, and reduce the expressions of HIF-1 and HSP70 in the case of cerebral I/R injury, thus exerting protective effects on rats with cerebral I/R injury.

A novel dentin bonding scheme based on extrafibrillar demineralization combined with covalent adhesion using a dry-bonding technique

Dentin bonding is a dynamic process that involves the penetration of adhesive resin monomers into the extrafibrillar and intrafibrillar demineralized collagen matrix using a wet-bonding technique. However, adhesive resin monomers lack the capacity to infiltrate the intrafibrillar space, and the excess water that is introduced by the wet-bonding technique remains at the bonding interface. This imperfectly bonded interface is inclined to hydrolytic degradation, severely jeopardizing the longevity of bonded clinical restorations. The present study introduces a dentin bonding scheme based on a dry-bonding technique, combined with the use of extrafibrillar demineralization and a collagen-reactive monomer (CRM)-based adhesive (CBA). Selective extrafibrillar demineralization was achieved using 1-wt% high-molecular weight (MW) carboxymethyl chitosan (CMCS) within a clinically acceptable timeframe to create a less aggressive bonding substance for dentin bonding due to its selectively extrafibrillar demineralization capacity. CMCS demineralization decreased the activation of in situ collagenase, improved the shrinking resistance of demineralized collagen, and thus provided stronger and more durable bonding than traditional phosphoric acid etching. The new dentin bonding scheme that contained CMCS and CBA and used a dry-bonding technique achieved an encouraging dentin bonding strength and durability with low technical sensitivity. This bonding scheme can be used to improve the stability of the resin-dentin interface and foster the longevity of bonded clinical restorations.

Regulation of H2O2-induced cells injury through Nrf2 signaling pathway: An introduction of a novel cysteic acid-modified peptide

A novel peptide (Cya-Phe-Leu-Ala-Pro, SCP) was formulated through non-protein amino acid-cysteic acid (Cya) modification of collagen peptide (Phe-Leu-Ala-Pro, CP) from Acaudina molpadioides. Introduction of this Cya showed remarkable improvement in the scavenging activities of OH·. SCP exhibited stronger effects than CP in preventing H₂O₂-induced oxidative damage due to lower levels of ROS and MDA, and higher activities of antioxidant enzymes, such as SOD, GSH-Px, HO-1, and NQO1. It was speculated that SCP could significantly increase the expression level of Nrf2 compared to CP, thereby activating the expression of downstream ARE genes. The expression levels of p38 in the upstream pathway to regulate Nrf2 content were significantly higher in both the CP and SCP-treated groups, while a higher level of JNK was observed only in the SCP-treated groups. The present study provided insights towards the application of cysteic acid modified peptide in protecting cell from oxidative damage through the JNK/Nrf2 pathway.

The antibacterial effect and physical performance of pit and fissure sealants based on an antibacterial core-shell nanocomposite

The application of pit and fissure sealants is a well-established method to prevent and treat early childhood caries. Resin-based sealants with antibacterial properties provide additional benefits for caries prevention in a cariogenic oral environment. The objective of this study was to evaluate the effect of an antibacterial core-shell AgBr/cationic polymer nanocomposite (AgBr/BHPVP) on the properties of a resin-based pit and fissure sealant. A commercialized pit and fissure sealant without fluoride, Concise (3M, ESPE, USA), was used as the parent material and negative control. Experimental antibacterial sealants were formulated by the addition of AgBr/BHPVP nanoparticles at mass fractions of 0.5, 1.0, and 1.5 wt% to the parent material. A fluoride-releasing sealant, Clinpro (3M, ESPE), was used as the positive control. Bacterial colony-forming unit (CFU) counts, metabolic activity tests, field emission-scanning electron microscopy (FE-SEM), and confocal laser scanning microscopy (CLSM) observations were used to evaluate the antibacterial properties of AgBr/BHPVP-modified sealants against Streptococcus mutans before and after five months of aging. The Vickers microhardness, degree of conversion, and microleakage level of the sealants were also investigated. According to the results of CFU counts and metabolic tests, sealants containing AgBr/BHPVP showed better contact-killing bactericidal activity against S. mutans than the two commercial sealants, irrespective of aging conditions (both P < 0.05). The AgBr/BHPVP-modified sealants also showed a significant inhibitory effect on the planktonic S. mutans around the cured sealant surfaces. In addition, the Vickers microhardness, degree of conversion, and microleakage level of the parent material were not damaged by modification with AgBr/BHPVP (P > 0.05). AgBr/BHPVP-modified pit and fissure sealant with a dual bactericidal mechanism is a promising option for the prevention of pit and fissure caries.

[Influence of Halogenated Hydroxyl-Alkanes Inhalation Anesthetic on the Determination of Ethanol Content in Blood]

Objective To study the influence of halogenated hydroxyl-alkanes inhalation anesthetic on the determination of ethanol content in blood. Methods Halogenated hydroxyl-alkanes were analyzed by headspace gas chromatography with double column confirmatory detection method. The influence of halogenated hydroxyl-alkanes on determination of ethanol content in blood sample by headspace gas chromatography was explored under the different detection conditions of KB-BAC1/ KB-BAC2 and J&W DB-ALC1/DB-ALC2 gas chromatographic column. Results The retention time of sevoflurane and enflurane was similar to that of ethanol and tert butanol respectively when using the J&W DB-ALC1/DB-ALC2 gas chromatographic column, and interfered with the detection of ethanol content in blood; only J&W DB-ALC1 gas chromatographic column can separate the sevoflurane and ethanol components, so as to eliminate their influence on the detection of ethanol content in blood. When using KB-BAC1/KB-BAC2 gas chromatographic column, the retention time of sevoflurane, isoflurane and ethanol is similar, especially that of sevoflurane and ethanol, and sevoflurane obviously interferes with the determination of ethanol content in blood. Conclusion Halogenated hydroxy-alkanes interfere with determination of ethanol content in blood by headspace gas chromatography. The interference can be discriminated effectively by choosing the suitable chromatographic column and double column confirmatory detection.