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1.
Open Heart ; 7(1)2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32393654

RESUMO

OBJECTIVE: To test whether intensive atorvastatin (ATV) increases the efficacy of transplantation with autologous bone marrow mononuclear cells (MNCs) in patients suffering from anterior ST-elevated myocardial infarction (STEMI). METHODS: This clinical trial was under a 2×2 factorial design, enrolling 100 STEMI patients, randomly into four groups of regular (RA) or intensive ATV (IA) with MNCs or placebo. The primary endpoint was the change of left ventricular ejection fraction (LVEF) at 1-year follow-up from baseline, primarily assessed by MRI. The secondary endpoints included other parameters of cardiac function, remodelling and regeneration determined by MRI, echocardiography, positron emission tomography (PET) and biomarkers. RESULTS: All the STEMI patients with transplantation of MNCs showed significantly increased LVEF change values than those with placebo (p=0.01) with only in the IA+MNCs patients group demonstrating significantly elevation of LVEF than in the IA+placebo group (+12.6% (95%CI 10.4 to 19.3) vs +5.0% (95%CI 4.0 to 10.0), p=0.001), pointing to a better synergy between ATV and MNCs (p=0.019). PET analysis revealed significantly increased viable areas of myocardium (p=0.015), while the scar sizes (p=0.026) and blood aminoterminal pro-B-type natriuretic peptide (p<0.034) reduced. All these above benefits of MNCs were also attributed to IA+MNCs instead of RA+MNCs group of patients with STEMI. CONCLUSIONS: Intensive ATV treatment augments the therapeutic efficacy of MNCs in patients with anterior STEMI at the convalescent stage. The treatment with the protocol of intensive ATV and MNC combination offers a clinically essential approach for myocardial infarction. TRIAL REGISTRATION NUMBER: NCT00979758.

2.
Int J Infect Dis ; 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32413609

RESUMO

BACKGROUNDS: The emerging virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a large outbreak of coronavirus disease COVID-19 in Wuhan, China since December 2019. The COVID-19 soon spread to other regions of China and overseas. In Hong Kong, local mitigation measures have been implemented since the first imported case was confirmed on January 23, 2020. Here we evaluated the temporal variation of detection delay from symptoms onset to laboratory confirmation of SARS-CoV-2 in Hong Kong. METHODS: A regression model is adopted to quantify the association between the SARS-CoV-2 detection delay and the calendar time. The association is tested and further validated by a Cox proportional hazard model. FINDINGS: The estimated median detection delay was 9.5 days (95%CI: 6.5-11.5) in the second half of January, and reduced to 6.0 days (95%CI: 5.5-9.5) in the first half of February 2020. We estimate that the SARS-CoV-2 detection efficiency improves at a daily rate of 5.40% (95%CI: 2.54-8.33) in Hong Kong. CONCLUSION: The detection efficiency of SARS-CoV-2 was likely being improved substantially in Hong Kong since the first imported case was detected. The sustaining enforcement in timely detection and other effective control measures are recommended to prevent the SARS-CoV-2 infection.

4.
Int J Infect Dis ; 96: 128-130, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32417744

RESUMO

Owing to the frequent travel connections between Wuhan and Zhejiang, Zhejiang was the third worst-affected province in China with 1,205 cases confirmed before 26 February 2020. The transmissibility of the 2019 novel coronavirus disease was monitored in Zhejiang, accounting for the transmissions from imported cases. Even though Zhejiang was one of the worst-affected provinces, an interruption of disease transmission (i.e. instantaneous reproduction numbers <1) was observed in early/mid-February after a comprehensive set of interventions combating the outbreak.

5.
Int J Infect Dis ; 95: 308-310, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32334115

RESUMO

The novel coronavirus disease 2019 (COVID-19) outbreak has caused 6088 cases and 41 deaths in Republic of Korea, and 3144 cases and 107 death in Italy by 5 March 2020, respectively. We modelled the transmission process in the Republic of Korea and Italy with a stochastic model, and estimated the basic reproduction number R0 as 2.6 (95% CI: 2.3-2.9) or 3.2 (95% CI: 2.9-3.5) in the Republic of Korea, under the assumption that the exponential growth starting on 31 January or 5 February 2020, and 2.6 (95% CI: 2.3-2.9) or 3.3 (95% CI: 3.0-3.6) in Italy, under the assumption that the exponential growth starting on 5 February or 10 February 2020, respectively.

7.
Dalton Trans ; 49(17): 5677-5683, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32292974

RESUMO

The "shuttle effect" of long-chain polysulfides and the low conductivity of elemental sulfur lead to the inferior cycling stability of lithium-sulfur batteries and imped their practical applications. Herein, Co3O4 nanoflakes with uniform macro pores distribution were synthesized via facile oil bath and calcination methods. Coupled with super P and coated on common polypropylene separators, they were expected to hinder the migration of lithium polysulfides (LiPSs) and accelerate the redox kinetics of polysulfides. Coin cells assembled with the Co3O4-super P interlayer exhibited a capacity of 760 mA h g-1 at 1 C, maintained 598 mA h g-1 after 350 cycles, and the decay rate of discharge capacity was only about 0.062% per cycle. Such high performance can be attributed to the synergistic effects between polar Co3O4 and conductive super P. The facile fabrication method and high performance make the Co3O4-super P interlayer a feasible material to apply in lithium-sulfur batteries.

8.
Int J Infect Dis ; 94: 145-147, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32315808

RESUMO

Asymptomatic transmission of the coronavirus disease 2019 is an important topic. A recent study in China showed that transmissibility of the asymptomatic cases is comparable to that of symptomatic cases. Here, we discuss that the conclusion may depend on how we interpret the data. To the best of our knowledge, this is the first time the relative transmissibility of asymptomatic COVID-19 infections is quantified.


Assuntos
Infecções Assintomáticas , Betacoronavirus , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , China , Humanos , Pandemias
9.
PLoS Negl Trop Dis ; 14(4): e0007502, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32348302

RESUMO

BACKGROUND: Between January 2015 and August 2016, two epidemic waves of Zika virus (ZIKV) disease swept the Northeastern (NE) region of Brazil. As a result, two waves of Guillain-Barré Syndrome (GBS) were observed concurrently. The mandatory reporting of ZIKV disease began region-wide in February 2016, and it is believed that ZIKV cases were significantly under-reported before that. The changing reporting rate has made it difficult to estimate the ZIKV infection attack rate, and studies in the literature vary widely from 17% to > 50%. The same applies to other key epidemiological parameters. In contrast, the diagnosis and reporting of GBS cases were reasonably reliable given the severity and easy recognition of the disease symptoms. In this paper, we aim to estimate the real number of ZIKV cases (i.e., the infection attack rate) and their dynamics in time, by scaling up from GBS surveillance data in NE Brazil. METHODOLOGY: A mathematical compartmental model is constructed that makes it possible to infer the true epidemic dynamics of ZIKV cases based on surveillance data of excess GBS cases. The model includes the possibility that asymptomatic ZIKV cases are infectious. The model is fitted to the GBS surveillance data and the key epidemiological parameters are inferred by using a plug-and-play likelihood-based estimation. We make use of regional weather data to determine possible climate-driven impacts on the reproductive number [Formula: see text], and to infer the true ZIKV epidemic dynamics. FINDINGS AND CONCLUSIONS: The GBS surveillance data can be used to study ZIKV epidemics and may be appropriate when ZIKV reporting rates are not well understood. The overall infection attack rate (IAR) of ZIKV is estimated to be 24.1% (95% confidence interval: 17.1%-29.3%) of the population. By examining various asymptomatic scenarios, the IAR is likely to be lower than 33% over the two ZIKV waves. The risk rate from symptomatic ZIKV infection to develop GBS was estimated as ρ = 0.0061% (95% CI: 0.0050%-0.0086%) which is significantly less than current estimates. We found a positive association between local temperature and the basic reproduction number, [Formula: see text]. Our analysis revealed that asymptomatic infections affect the estimation of ZIKV epidemics and need to also be carefully considered in related modelling studies. According to the estimated effective reproduction number and population wide susceptibility, we comment that a ZIKV outbreak would be unlikely in NE Brazil in the near future.

10.
Int J Mol Sci ; 21(6)2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245276

RESUMO

Vascular plant one-zinc-finger (VOZ) transcription factor, a plant specific one-zinc-finger-type transcriptional activator, is involved in regulating numerous biological processes such as floral induction and development, defense against pathogens, and response to multiple types of abiotic stress. Six VOZ transcription factor-encoding genes (GmVOZs) have been reported to exist in the soybean (Glycine max) genome. In spite of this, little information is currently available regarding GmVOZs. In this study, GmVOZs were cloned and characterized. GmVOZ genes encode proteins possessing transcriptional activation activity in yeast cells. GmVOZ1E, GmVOZ2B, and GmVOZ2D gene products were widely dispersed in the cytosol, while GmVOZ1G was primarily located in the nucleus. GmVOZs displayed a differential expression profile under dehydration, salt, and salicylic acid (SA) stress conditions. Among them, GmVOZ1G showed a significantly induced expression in response to all stress treatments. Overexpression of GmVOZ1G in soybean hairy roots resulted in a greater tolerance to drought and salt stress. In contrast, RNA interference (RNAi) soybean hairy roots suppressing GmVOZ1G were more sensitive to both of these stresses. Under drought treatment, soybean composite plants with an overexpression of hairy roots had higher relative water content (RWC). In response to drought and salt stress, lower malondialdehyde (MDA) accumulation and higher peroxidase (POD) and superoxide dismutase (SOD) activities were observed in soybean composite seedlings with an overexpression of hairy roots. The opposite results for each physiological parameter were obtained in RNAi lines. In conclusion, GmVOZ1G positively regulates drought and salt stress tolerance in soybean hairy roots. Our results will be valuable for the functional characterization of soybean VOZ transcription factors under abiotic stress.

13.
Int J Infect Dis ; 94: 29-31, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171951

RESUMO

As of March 1, 2020, Iran had reported 987 novel coronavirus disease (COVID-19) cases, including 54 associated deaths. At least six neighboring countries (Bahrain, Iraq, Kuwait, Oman, Afghanistan, and Pakistan) had reported imported COVID-19 cases from Iran. In this study, air travel data and the numbers of cases from Iran imported into other Middle Eastern countries were used to estimate the number of COVID-19 cases in Iran. It was estimated that the total number of cases in Iran was 16 533 (95% confidence interval: 5925-35 538) by February 25, 2020, before the UAE and other Gulf Cooperation Council countries suspended inbound and outbound flights from Iran.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Doença Relacionada a Viagens , Viagem Aérea , Humanos , Irã (Geográfico) , Pandemias
14.
Int J Infect Dis ; 93: 211-216, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32145465

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) outbreak, emerged in Wuhan, China in the end of 2019, has claimed more than 2600 lives as of 24 February 2020 and posed a huge threat to global public health. The Chinese government has implemented control measures including setting up special hospitals and travel restriction to mitigate the spread. We propose conceptual models for the COVID-19 outbreak in Wuhan with the consideration of individual behavioural reaction and governmental actions, e.g., holiday extension, travel restriction, hospitalisation and quarantine. We employe the estimates of these two key components from the 1918 influenza pandemic in London, United Kingdom, incorporated zoonotic introductions and the emigration, and then compute future trends and the reporting ratio. The model is concise in structure, and it successfully captures the course of the COVID-19 outbreak, and thus sheds light on understanding the trends of the outbreak.


Assuntos
Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Modelos Biológicos , Pneumonia Viral/epidemiologia , Saúde Pública/legislação & jurisprudência , Betacoronavirus , China/epidemiologia , Governo , Regulamentação Governamental , Humanos , Influenza Pandêmica, 1918-1919/estatística & dados numéricos , Pandemias , Quarentena , Viagem/legislação & jurisprudência , Reino Unido/epidemiologia
16.
Environ Sci Technol ; 54(7): 4036-4045, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32131590

RESUMO

Phylogenetically diverse species of bacteria can mediate anaerobic oxidation of ferrous iron [Fe(II)] and/or arsenite [As(III)] coupled to nitrate reduction, impacting the biogeochemical cycles of Fe and As. However, the mechanisms for nitrate-dependent anaerobic oxidation of Fe(II) and As(III) remain unclear. In this study, we isolated two bacterial strains from arsenic-contaminated paddy soils, Ensifer sp. ST2 and Paracoccus sp. QY30. Both strains were capable of anaerobic As(III) oxidation, but only QY30 could oxidize Fe(II) under nitrate-reducing conditions. Both strains contain the As(III) oxidase gene aioA, whose expression was induced greatly by As(III) exposure. Both strains contain the whole suite of genes for complete denitrification, but the nitrite reductase gene nirK was not expressed in QY30 and nitrite accumulated under nitrate-reducing conditions. When the functional nirK gene was knocked out in strain ST2, its nitrite reduction ability was completely abolished and nitrite accumulated in the medium. Moreover, the ST2ΔnirK mutant gained the ability to oxidize Fe(II). When nirK gene from ST2 was introduced to QY30, the recombinant strain QY30::nirK gained the ability to reduce nitrite but lost the ability to oxidize Fe(II). These genetic manipulations did not affect the ability of both strains to oxidize As(III). Our results indicate that nitrite accumulation is required for anaerobic oxidation of Fe(II) but not for As(III) oxidation in these strains. The results suggest that anaerobic Fe(II) oxidation in the two bacterial strains is primarily driven by abiotic reaction of Fe(II) with nitrite, while reduction of nitrate to nitrite is sufficient for redox coupling with anaerobic As(III) oxidation catalyzed by Aio. Deletion of nirK gene in denitrifiers can enhance anaerobic Fe(II) oxidation.

17.
BMC Plant Biol ; 20(1): 123, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32192425

RESUMO

BACKGROUND: Crop productivity is challenged by abiotic stresses, among which drought stress is the most common. NF-Y genes, especially NF-YA genes, regulate tolerance to abiotic stress. RESULTS: Soybean NF-Y gene GmNFYA5 was identified to have the highest transcript level among all 21 NF-YA genes in soybean (Glycine max L.) under drought stress. Drought-induced transcript of GmNFYA5 was suppressed by the ABA synthesis inhibitor naproxen (NAP). GmNFYA5 transcript was detected in various tissues at vegetative and reproductive growth stages with higher levels in roots and leaves than in other tissues, which was consist with the GmNFYA5 promoter: GUS fusion assay. Overexpression of GmNFYA5 in transgenic Arabidopsis plants caused enhanced drought tolerance in seedlings by decreasing stomatal aperture and water loss from leaves. Overexpression and suppression of GmNFYA5 in soybean resulted in increased and decreased drought tolerance, respectively, relative to plants with an empty vector (EV). Transcript levels of ABA-dependent genes (ABI2, ABI3, NCED3, LEA3, RD29A, P5CS1, GmWRKY46, GmNCED2 and GmbZIP1) and ABA-independent genes (DREB1A, DREB2A, DREB2B, GmDREB1, GmDREB2 and GmDREB3) in transgenic plants overexpressing GmNFYA5 were higher than those of wild-type plants under drought stress; suppression of GmNFYA5 transcript produced opposite results. GmNFYA5 probably regulated the transcript abundance of GmDREB2 and GmbZIP1 by binding to the promoters in vivo. CONCLUSIONS: Our results suggested that overexpression of GmNFYA5 improved drought tolerance in soybean via both ABA-dependent and ABA-independent pathways.

20.
J Theor Biol ; 493: 110209, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32097608

RESUMO

Lassa fever, also known as Lassa hemorrhagic fever, is a virus that has generated recurrent outbreaks in West Africa. We use mechanistic modelling to study the Lassa fever epidemics in Nigeria from 2016-19. Our model describes the interaction between human and rodent populations with the consideration of quarantine, isolation and hospitalization processes. Our model supports the phenomenon of forward bifurcation where the stability between disease-free equilibrium and endemic equilibrium exchanges. Moreover, our model captures well the incidence curves from surveillance data. In particular, our model is able to reconstruct the periodic rodent and human forces of infection. Furthermore, we suggest that the three major epidemics from 2016-19 can be modelled by properly characterizing the rodent (or human) force of infection while the estimated human force of infection also present similar patterns across outbreaks. Our results suggest that the initial susceptibility likely increased across the three outbreaks from 2016-19. Our results highlight the similarity of the transmission dynamics driving three major Lassa fever outbreaks in the endemic areas.

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