Wuhan was the first epicentre of COVID-19 in the world, accounting for 80% of cases in China during the first wave. We aimed to assess household transmissibility of severe acute respiratory syndrome ...coronavirus 2 (SARS-CoV-2) and risk factors associated with infectivity and susceptibility to infection in Wuhan.
This retrospective cohort study included the households of all laboratory-confirmed or clinically confirmed COVID-19 cases and laboratory-confirmed asymptomatic SARS-CoV-2 infections identified by the Wuhan Center for Disease Control and Prevention between Dec 2, 2019, and April 18, 2020. We defined households as groups of family members and close relatives who did not necessarily live at the same address and considered households that shared common contacts as epidemiologically linked. We used a statistical transmission model to estimate household secondary attack rates and to quantify risk factors associated with infectivity and susceptibility to infection, accounting for individual-level exposure history. We assessed how intervention policies affected the household reproductive number, defined as the mean number of household contacts a case can infect.
27 101 households with 29 578 primary cases and 57 581 household contacts were identified. The secondary attack rate estimated with the transmission model was 15·6% (95% CI 15·2–16·0), assuming a mean incubation period of 5 days and a maximum infectious period of 22 days. Individuals aged 60 years or older were at a higher risk of infection with SARS-CoV-2 than all other age groups. Infants aged 0–1 years were significantly more likely to be infected than children aged 2–5 years (odds ratio OR 2·20, 95% CI 1·40–3·44) and children aged 6–12 years (1·53, 1·01–2·34). Given the same exposure time, children and adolescents younger than 20 years of age were more likely to infect others than were adults aged 60 years or older (1·58, 1·28–1·95). Asymptomatic individuals were much less likely to infect others than were symptomatic cases (0·21, 0·14–0·31). Symptomatic cases were more likely to infect others before symptom onset than after (1·42, 1·30–1·55). After mass isolation of cases, quarantine of household contacts, and restriction of movement policies were implemented, household reproductive numbers declined by 52% among primary cases (from 0·25 95% CI 0·24–0·26 to 0·12 0·10–0·13) and by 63% among secondary cases (from 0·17 0·16–0·18 to 0·063 0·057–0·070).
Within households, children and adolescents were less susceptible to SARS-CoV-2 infection but were more infectious than older individuals. Presymptomatic cases were more infectious and individuals with asymptomatic infection less infectious than symptomatic cases. These findings have implications for devising interventions for blocking household transmission of SARS-CoV-2, such as timely vaccination of eligible children once resources become available.
National Natural Science Foundation of China, Fundamental Research Funds for the Central Universities, US National Institutes of Health, and US National Science Foundation.
China is one of the countries with the highest incidence of gastric cancer. There are differences in epidemiological characteristics, clinicopathological features, tumor biological characteristics, ...treatment patterns, and drug selection between gastric cancer patients from the Eastern and Western countries. Non‐Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients. The Chinese Society of Clinical Oncology (CSCO) arranged for a panel of senior experts specializing in all sub‐specialties of gastric cancer to compile, discuss, and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence‐based medicine in China and abroad. By referring to the opinions of industry experts, taking into account of regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted experts’ consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes. This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis, comprehensive treatment, and follow‐up visits for gastric cancer.
Single‐cell and in situ cell‐based operation with nanopipette approach offers a possibility to elucidate the intracellular processes and may aid the improvement of therapy efficiency and precision. ...We present here a photo‐responsive hydrogel‐nanopipette hybrid system that can achieve single‐cell operation with high spatial/temporal resolution and negligible cell damage. This strategy overcomes long‐time obstacles in nanopipette single‐cell studies as high electric potential (ca. 1000 mV) or organic solvent is always used during operations, which would inevitably impose disturbance and damage to targeted cells. The light‐triggered system promotes a potential‐free, non‐invasive single‐cell injection, resulting in a well‐retained cell viability (90 % survival rate). Moreover, the photo‐driven injection enables a precisely dose‐controllable single‐cell drug delivery. Significantly reduced lethal doses of doxorubicin (163–217 fg cell−1) are demonstrated in corresponding cell lines.
The fabrication of photo‐responsive hydrogel‐nanopipette system ensures both precision single‐cell operation and high cell preservation. Upon light‐controlled, non‐invasive operation, a high cell viability over 90 % as well as precise quantification of injection are obtained. Hence, a single‐cell precise‐dosing is achieved with a minimum lethal dose of 163–217 fg cell−1.
Since its discovery in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 2 180 000 people worldwide and has caused more than 150 000 deaths as of ...April 16, 2020. SARS-CoV-2, which is the virus causing coronavirus disease 2019 (COVID-19), uses the angiotensin-converting enzyme 2 (ACE2) as a cell receptor to invade human cells. Thus, ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection. This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.
We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger (ages ≤ 49 years) and older (ages > 49 years) persons using two-sided Student's t test. We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.
ACE2 expression levels were the highest in the small intestine, testis, kidneys, heart, thyroid, and adipose tissue, and were the lowest in the blood, spleen, bone marrow, brain, blood vessels, and muscle. ACE2 showed medium expression levels in the lungs, colon, liver, bladder, and adrenal gland. ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue. In the skin, digestive system, brain, and blood vessels, ACE2 expression levels were positively associated with immune signatures in both males and females. In the thyroid and lungs, ACE2 expression levels were positively and negatively associated with immune signatures in males and females, respectively, and in the lungs they had a positive and a negative correlation in the older and younger groups, respectively.
Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes, ages, and races equally. The different host immune responses to SARS-CoV-2 infection may partially explain why males and females, young and old persons infected with this virus have markedly distinct disease severity. This study provides new insights into the role of ACE2 in the SARS-CoV-2 pandemic.
Preparation of reliable, stable, and highly responsive gas-sensing devices for the detection of acetone has been considered to be a key issue for the development of accurate disease diagnosis systems ...via exhaled breath. In this paper, novel CeO2 nanodot-decorated WO3 nanowires are successfully synthesized through a sequential hydrothermal and thermolysis process. Such CeO2 nanodot-decorated WO3 nanowires exhibited a remarkable enhancement in acetone-sensing performance based on a miniaturized micro-electromechanical system device, which affords high response (S = 1.30–500 ppb, 1.62–2.5 ppm), low detection limit (500 ppb), and superior selectivity toward acetone. The improved performance of the acetone sensor is likely to be originated from the fast carrier transportation of WO3 nanowires, the formation of WO3–CeO2 heterojunctions, and the existence of large amounts of oxygen vacancies in CeO2. The improved reaction thermodynamics and sensing mechanisms have also been revealed by the specific band alignment and X-ray photoelectron spectroscopy analysis.
Background
Mesenchymal stem cell (MSC) infusion was reported to improve liver function in patients with decompensated liver cirrhosis (DLC); however, whether the medication can improve outcome of ...these patients is poorly understood.
Methods
This prospective, open-labeled, randomized controlled study enrolled 219 patients with HBV-related DLC who were divided into control group (
n
= 111) and umbilical cord-derived MSC (UC-MSC)-treated group (
n
= 108), then all of them received a follow-up check from October 2010 to October 2017. The treated patients received three times of UC-MSC infusions at 4-week intervals plus conventional treatment that was only used for control group. The overall survival rate and HCC-free survival rate were calculated as primary endpoints and the liver function and adverse events associated with the medication were also evaluated.
Results
During the follow-up check period from 13 to 75th months, there was a significantly higher overall survival rate in the treated group than the control group, while the difference of the hepatocellular carcinoma event-free survival rate between the treated and control groups was not observed during the 75-month follow-up. UC-MSC treatment markedly improved liver function, as indicated by the levels of serum albumin, prothrombin activity, cholinesterase, and total bilirubin during 48 weeks of follow-up. No significant side effects or treatment-related complications were observed in the UC-MSC group.
Conclusions
Therapy of UC-MSC is not only well tolerated, but also significantly improves long-term survival rate, as well as the liver function in patients with HBV-related DLC. UC-MSC medication, therefore, might present a novel therapeutic approach for the disease.
Graphic abstract
Emerging infectious diseases, such as severe acute respiratory syndrome (SARS) and Zika virus disease, present a major threat to public health
. Despite intense research efforts, how, when and where ...new diseases appear are still a source of considerable uncertainty. A severe respiratory disease was recently reported in Wuhan, Hubei province, China. As of 25 January 2020, at least 1,975 cases had been reported since the first patient was hospitalized on 12 December 2019. Epidemiological investigations have suggested that the outbreak was associated with a seafood market in Wuhan. Here we study a single patient who was a worker at the market and who was admitted to the Central Hospital of Wuhan on 26 December 2019 while experiencing a severe respiratory syndrome that included fever, dizziness and a cough. Metagenomic RNA sequencing
of a sample of bronchoalveolar lavage fluid from the patient identified a new RNA virus strain from the family Coronaviridae, which is designated here 'WH-Human 1' coronavirus (and has also been referred to as '2019-nCoV'). Phylogenetic analysis of the complete viral genome (29,903 nucleotides) revealed that the virus was most closely related (89.1% nucleotide similarity) to a group of SARS-like coronaviruses (genus Betacoronavirus, subgenus Sarbecovirus) that had previously been found in bats in China
. This outbreak highlights the ongoing ability of viral spill-over from animals to cause severe disease in humans.
Soaring cases of coronavirus disease (COVID-19) are pummeling the global health system. Overwhelmed health facilities have endeavored to mitigate the pandemic, but mortality of COVID-19 continues to ...increase. Here, we present a mortality risk prediction model for COVID-19 (MRPMC) that uses patients' clinical data on admission to stratify patients by mortality risk, which enables prediction of physiological deterioration and death up to 20 days in advance. This ensemble model is built using four machine learning methods including Logistic Regression, Support Vector Machine, Gradient Boosted Decision Tree, and Neural Network. We validate MRPMC in an internal validation cohort and two external validation cohorts, where it achieves an AUC of 0.9621 (95% CI: 0.9464-0.9778), 0.9760 (0.9613-0.9906), and 0.9246 (0.8763-0.9729), respectively. This model enables expeditious and accurate mortality risk stratification of patients with COVID-19, and potentially facilitates more responsive health systems that are conducive to high risk COVID-19 patients.
•Co-adsorption of Cu(II) and TC on PE microplastics with biofilm was first studied.•Biofilm enhanced the adsorption and stabilization of Cu(II) and TC on microplastics.•Competition and complexation ...interactions were involved in the adsorption process.•Microplastics with biofilm act as carriers of heavy metals and antibiotics in water.
In this study, the adsorption properties of Cu(II) and tetracycline (TC) onto virgin and biofilm-developed polyethylene (PE) microplastics were investigated in batch sorption experiments. PE microplastics were placed at sewage outlets (Shanghai, China) for 20 days to develop biofilm on their surface. The adsorption and desorption isotherms of Cu(II) and TC were well fitted by the Freundlich model, and revealed that biofilm could enhance the adsorption and stabilization of Cu(II) and TC on microplastics. The linearity test of the film diffusion model in kinetic experiments suggested that the adsorption on virgin and biofilm-developed microplastics was dominated by intra-particle diffusion and film diffusion, respectively. Compared with the virgin microplastics, the adsorption of Cu(II) and TC on biofilm-developed microplastics was additionally affected by pH-dependent complexation interactions in the biofilm and competition interactions. Cu(II) pre-adsorbed on the biofilm could be released into solution because of competition effects of TC. Fourier transform infrared spectroscopy (FTIR) and density functional theory (DFT) further confirmed that the enhanced adsorption of TC on the biofilm could be attributed to the complexation of TC, Cu(II) and components in biofilm. This study illustrated that biofilms could enhance the role of microplastics in the Cu(II) and TC migration by changing their adsorption properties on microplastics.
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