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1.
Viruses ; 16(1)2024 01 11.
Article in English | MEDLINE | ID: mdl-38257804

ABSTRACT

BACKGROUND: Mpox virus (MPXV) infections have increased in many countries since May 2022, increasing demand for diagnostic tests and research on the virus. To ensure personnel safety, appropriate and reliable measures are needed to disinfect and inactivate infectious samples; Methods: We evaluated the stability of infectious MPXV cultures stored at different temperatures and through freeze-thaw cycles. Heat physical treatment (56 °C, 70 °C, 95 °C), chemical treatment (beta-propiolactone (BPL)) and two commercialized disinfectants (Micro-Chem Plus (MCP) and ethanol) were tested against infectious MPXV cultures; Results: The results indicated that MPXV stability increases with lower temperatures. The MPXV titer was stable within three freeze-thaw cycles and only decreased by 1.04 log10 (lg) 50% cell culture infective dose (CCID50) per milliliter (12.44%) after twelve cycles. MPXV could be effectively inactivated at 56 °C for 40 min, 70 °C for 10 min, and 95 °C for 5 min. For BPL inactivation, a 1:1000 volume ratio (BPL:virus) could also effectively inactivate MPXV. A total of 2% or 5% MCP and 75% ethanol treated with MPXV for at least 1 min could reduce >4.25 lg; Conclusions: MPXV shows high stability to temperature and freeze-thaw. Heat and BPL treatments are effective for the inactivation of MPXV, while MCP and ethanol are effective for disinfection, which could help laboratory staff operate the MPXV under safer conditions and improve operational protocols.


Subject(s)
Disinfectants , Disinfection , Humans , Monkeypox virus , Disinfectants/pharmacology , Cell Culture Techniques , Ethanol/pharmacology , Propiolactone
2.
Vaccines (Basel) ; 12(1)2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38250869

ABSTRACT

BACKGROUND: Large-scale vaccine production requires downstream processing that focuses on robustness, efficiency, and cost-effectiveness. METHODS: To assess the robustness of the current vaccine production process, three batches of COVID-19 Omicron BA.1 strain hydrolytic concentrated solutions were selected. Four gel filtration chromatography media (Chromstar 6FF, Singarose FF, Bestarose 6B, and Focurose 6FF) and four ion exchange chromatography media (Maxtar Q, Q Singarose, Diamond Q, and Q Focurose) were used to evaluate their impact on vaccine purification. The quality of the vaccine was assessed by analyzing total protein content, antigen content, residual Vero cell DNA, residual Vero cell protein, and residual bovine serum albumin (BSA). Antigen recovery rate and specific activity were also calculated. Statistical analysis was conducted to evaluate process robustness and the purification effects of the chromatography media. RESULTS: The statistical analysis revealed no significant differences in antigen recovery (p = 0.10), Vero HCP residue (p = 0.59), Vero DNA residue (p = 0.28), and BSA residue (p = 0.97) among the three batches of hydrolytic concentrated solutions processed according to the current method. However, a significant difference (p < 0.001) was observed in antigen content. CONCLUSIONS: The study demonstrated the remarkable robustness of the current downstream process for producing WIBP-CorV vaccines. This process can adapt to different batches of hydrolytic concentrated solutions and various chromatography media. The research is crucial for the production of inactivated SARS-CoV-2 vaccines and provides a potential template for purifying other viruses.

3.
Hum Vaccin Immunother ; 19(1): 2211896, 2023 12 31.
Article in English | MEDLINE | ID: mdl-37249318

ABSTRACT

This phase III clinical trial aimed to assess the safety and demonstrate the immunogenicity of a candidate freeze-dried purified Vero cell-based rabies vaccine (PVRV-WIBP) developed for human use. A cohort of 40 participants in stage 1 and 1956 subjects in stage 2 with an age range of 10-50 years were recruited for the phase III clinical trial. For safety analysis in stage 1, 20 participants received either 4-dose or 5-dose regimen of PVRV-WIBP. In stage 2, 1956 subjects were randomly divided into the 5-dose PVRV-WIBP, 5-dose PVRV-LNCD, and 4-dose PVRV-WIBP groups. The serum neutralizing antibody titer against rabies was determined on day 7 or 14 and day 35 or 42. Adverse reactions were recorded for more than 6 months. Most adverse reactions, which were mild and moderate in severity, occurred and resolved within 1 week after each injection in the PVRV-WIBP (4 and 5 doses) and PVRV-LNCD (5 doses) groups. All three groups achieved complete seroconversion 14 days after the initial dose and 14 days after completing the full vaccination schedule, the susceptible subjects in the PVRV-WIBP group (4-dose or 5-dose regimen) displayed higher neutralizing antibody titers against the rabies virus compared to those in the PVRV-LNCD group (5-dose regimen). PVRV-WIBP induced non-inferior immune responses versus PVRV-LNCD as assessed by seroconversion rate. PVRV-WIBP was well tolerated and non-inferior to PVRV-LNCD in healthy individuals aged 10-50 years. The results indicated that PVRV-WIBP (both 4- and 5-dose schedules) could be an alternative to rabies post-exposure prophylaxis.


Subject(s)
HIV Seropositivity , Rabies Vaccines , Rabies virus , Rabies , Animals , Chlorocebus aethiops , Humans , Child , Adolescent , Young Adult , Adult , Middle Aged , Rabies/prevention & control , East Asian People , Antibodies, Viral , Antibodies, Neutralizing , Vero Cells , Immunogenicity, Vaccine
4.
Materials (Basel) ; 15(10)2022 May 10.
Article in English | MEDLINE | ID: mdl-35629458

ABSTRACT

Single-phase monazite-type ceramics are considered as potential host matrices for the conditioning of separated plutonium and minor actinides. Sm-orthophosphates were synthesised and their behaviour under irradiation was investigated with respect to their long-term performance in the repository environment. Sintered SmPO4 pellets and thin lamellae were irradiated with 1, 3.5, and 7 MeV Au ions, up to fluences of 5.1 × 1014 ions cm-2 to simulate ballistic effects of recoiling nuclei resulting from α-decay of incorporated actinides. Threshold displacement energies for monazite-type SmPO4 subsequently used in SRIM/TRIM simulations were derived from atomistic simulations. Raman spectra obtained from irradiated lamellae revealed vast amorphisation at the highest fluence used, although local annealing effects were observed. The broadened, but still discernible, band of the symmetrical stretching vibration in SmPO4 and the negligible increase in P-O bond lengths suggest that amorphisation of monazite is mainly due to a breaking of Ln-O bonds. PO4 groups show structural disorder in the local environment but seem to behave as tight units. Annealing effects observed during the irradiation experiment and the distinctively lower dose rates incurred in actinide bearing waste forms and potential α-radiation-induced annealing effects indicate that SmPO4-based waste forms have a high potential for withstanding amorphisation.

5.
Front Psychiatry ; 13: 868072, 2022.
Article in English | MEDLINE | ID: mdl-35509890

ABSTRACT

The longitudinal relationship between students' pre-existing adaptability and subsequent sleep and mental health during the COVID-19 pandemic has not been studied. The present study examines the relationship between adaptability and students' anxiety, depression, and insomnia during and after the lockdown related to COVID-19. 5,235 university students participated in a longitudinal study with three time points. Students completed the Adaptability Scale before the outbreak (October 2019; Time 1), the Insomnia Severity Index (ISI) both during (April 2020; Time 2) and after lockdown (March 2021; Time 3), the Anxiety and Depression subscales of the SCL-90 (at Time 1 and 3), and the SAS/SDS (at Time 2). The results showed that self-reported adaptability is significantly negatively correlated with anxiety and depression, and that anxiety and depression are positively correlated with insomnia. Furthermore, adaptability protects from insomnia both directly and through its negative relationship with anxiety and depression. This study sheds light on the internal mechanisms mediating the relationship between students' adaptability and experience of insomnia in challenging circumstances. Implications for curtailing the negative effects of stressful events on students' sleep health by improving their adaptability and reducing their anxiety and depression are discussed.

6.
Front Psychol ; 12: 706601, 2021.
Article in English | MEDLINE | ID: mdl-34295294

ABSTRACT

Although accumulating evidence suggests the COVID-19 pandemic is associated with costs in mental health, the development of students' mental health, including the change from their previous levels of depression and anxiety and the factors associated with this change, has not been well-studied. The present study investigates changes in students' anxiety and depression from before the pandemic to during the lockdown and identifies factors that are associated with these changes. 14,769 university students participated in a longitudinal study with two time points with a 6-month interval. Students completed the Anxiety and Depression subscales of the Symptom Checklist 90 (SCL-90) before the COVID-19 outbreak (October 2020, Time 1), and the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) during the pandemic (April 2020, Time 2). The prevalence of anxiety and depression symptoms were 1.44 and 1.46% at Time 1, and 4.06 and 22.09% at Time 2, respectively, showing a 181.94% increase in anxiety and a 1413.01% increase in depression. Furthermore, the increases in anxiety and depression from pre-pandemic levels were associated with students' gender and the severity of the pandemic in the province where they resided. This study contributes to the gap in knowledge regarding changes in students' mental health in response to the pandemic and the role of local factors in these changes. Implications for gender and the Typhoon Eye effect are discussed.

7.
Front Chem ; 7: 197, 2019.
Article in English | MEDLINE | ID: mdl-31001521

ABSTRACT

Lanthanide phosphates (LnPO 4) are considered as a potential nuclear waste form for immobilization of Pu and minor actinides (Np, Am, and Cm). In that respect, in the recent years we have applied advanced atomistic simulation methods to investigate various properties of these materials on the atomic scale. In particular, we computed several structural, thermochemical, thermodynamic and radiation damage related parameters. From a theoretical point of view, these materials turn out to be excellent systems for testing quantum mechanics-based computational methods for strongly correlated electronic systems. On the other hand, by conducting joint atomistic modeling and experimental research, we have been able to obtain enhanced understanding of the properties of lanthanide phosphates. Here we discuss joint initiatives directed at understanding the thermodynamically driven long-term performance of these materials, including long-term stability of solid solutions with actinides and studies of structural incorporation of f elements into these materials. In particular, we discuss the maximum load of Pu into the lanthanide-phosphate monazites. We also address the importance of our results for applications of lanthanide-phosphates beyond nuclear waste applications, in particular the monazite-xenotime systems in geothermometry. For this we have derived a state-of-the-art model of monazite-xenotime solubilities. Last but not least, we discuss the advantage of usage of atomistic simulations and the modern computational facilities for understanding of behavior of nuclear waste-related materials.

8.
Biologicals ; 55: 59-62, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29970288

ABSTRACT

The NIH potency test for human rabies vaccines has disadvantages for use, especially in developing countries where rabies is endemic and prophylaxis needs ample, rapid, and reliable vaccine supplies. In China, 60-75 million doses of human rabies vaccines are administered each year. Vaccine quality control is of paramount importance, as is the release of potency-validated vaccines. We intended to design an alternative to the NIH in vivo method, and developed a relative potency test using an ELISA. Using Pearson's correlation analysis, we found a close relationship between the rabies vaccine glycoprotein content in vitro and the potency values in vivo. We suggest the relative potency test developed here as a simplified method for human rabies vaccine quality control in China and a possible alternative to the NIH method.


Subject(s)
Rabies Vaccines/chemistry , Rabies Vaccines/immunology , Vaccine Potency , Animals , China , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Male , Mice , Quality Control
9.
Inorg Chem ; 57(11): 6252-6265, 2018 Jun 04.
Article in English | MEDLINE | ID: mdl-29762025

ABSTRACT

This study investigates the incorporation of the minor actinide curium (Cm3+) in a series of synthetic La1- xGd xPO4 ( x = 0, 0.24, 0.54, 0.83, 1) monazite and rhabdophane solid-solutions. To obtain information on the incorporation process on the molecular scale and to understand the distribution of the dopant in the synthetic phosphate phases, combined time-resolved laser fluorescence spectroscopy and X-ray absorption fine structure spectroscopy investigations were conducted and complemented with ab initio atomistic simulations. We found that Cm3+ is incorporated in the monazite endmembers (LaPO4 and GdPO4) on one specific, highly ordered lattice site. The intermediate solid-solutions, however, display increasing disorder around the Cm3+ dopant as a result of random variations in nearest neighbor distances. In hydrated rhabdophane, and especially its La-rich solid-solutions, Cm3+ is preferentially incorporated on nonhydrated lattice sites. This site occupancy is not in agreement with the hydrated rhabdophane structure, where two-thirds of the lattice sites are associated with water of hydration (LnPO4·0.67H2O), implying that structural substitution reactions cannot be predicted based on the structure of the host matrix only.

10.
Di Yi Jun Yi Da Xue Xue Bao ; 23(2): 179-80, 2003 Feb.
Article in Chinese | MEDLINE | ID: mdl-12581977

ABSTRACT

OBJECTIVE: To study the clinical characteristics, diagnosis, and surgical treatment of primary cardiac tumors. METHOD: The clinical features and surgical results in 126 cases (1971-2000) of primary cardiac tumors were analyzed retrospectively. RESULTS: Among the 121 patients with benign tumors were treated surgically, 6 had recurrence of the pathologically confirmed intracardiac myxoma in a period of 1 to 7 years after surgery, and all were cured after reoperation. Follow-up of these patients showed satisfying long-term survival. In the other 5 malignant cases, 1 died during the perioperative period, and the others died of progressive heart failure, cardiac tamponade and cardiac rupture, respectively, within 10 months after the final diagnosis. CONCLUSION: The symptoms of primary cardiac tumor are diverse and complex, and echocardiography, CT, MRI are instrumental for a definite early diagnosis. In case of benign tumors, operation usually produces good results, but for malignant tumors characterized by rapid progression, earlier surgical removal in combination with other therapeutic modalities may improve the prognosis.


Subject(s)
Heart Neoplasms/diagnosis , Heart Neoplasms/surgery , Adolescent , Adult , Aged , Child , Female , Heart Neoplasms/physiopathology , Humans , Male , Middle Aged
11.
Di Yi Jun Yi Da Xue Xue Bao ; 22(6): 536-8, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12297479

ABSTRACT

OBJECTIVE: To understand the pathological features of congenital dextrocardia and explore its diagnosis and surgical treatment. METHOD: The clinical data from 32 cases of congenital dextrocardia were collected to understand the major cardiac anomalies and evaluate the diagnostic approaches of this disease. Analysis of the effect of surgical treatment was also conducted in 16 among the 32 cases. RESULTS: Complex anomalies such as transposition of great artery (TGA), single ventricle (SV), common trunk (CMT) formation for the arteries were found in 8 out of 13 mirror-image dextrocardia cases, most of the dextroversion (DV) accompanied by physiological correction of the TGA (C-TGA, 11/17) which often involved ventricle septal defect (VSD) and pulmonary stenosis (PS, 8/11). Another 2 cases diagnosed as isolated dextrocardia (IDC) also suffered TGA combined with complete atrioventricular canal (CAVC) defect. Definite diagnoses of dextrocardia (DC) were derived from X-ray examination, including thoracic-abdominal plain X-ray film, hilar computed tomography, high kV chest plain film or ultrafast CT, echocardiogram and angiography. Fontan operation was performed in 8 cases and anatomical correction in 7 with surgical exploration in 1 case. Thirteen patients survived, among whom 8 had complex cardiac defect and 5 of them received modified Fontan operation or total cavopulmonary connection (TCPC). CONCLUSIONS: Complex cardiac anomalies are not rare in mirror-image dextrocardia, and dextroversion and isolated dextrocardia were usually related to C-TGA+VSD+PS and TGA+CAVC respectively. X-ray examinations are of great significance in the diagnoses and classification of dextrocardia, and echocardiogram and ultrafast CT constitute the major modalities for clarifying intracardial defect and surgical indications. Fontan operations, including modified Fontan and total cavopulmonary connection, might be hopeful surgical treatment for complex congenital heart disease when indications are carefully evaluated.


Subject(s)
Dextrocardia/surgery , Adolescent , Child , Child, Preschool , Dextrocardia/diagnosis , Female , Humans , Infant , Male , Treatment Outcome
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