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BackgroundThe kinetics of the neutralizing antibody response against SARS-CoV-2 is crucial for responding to the pandemic as well as developing vaccination strategies. We aimed to fit the antibody curves in symptomatic and asymptomatic individuals. MethodsWe systematically searched PubMed, Embase, Web of Science, and Europe PMC for articles published in English between Jan 1, 2020, and Oct 2, 2022. Studies evaluating neutralizing antibody from people who had a natural SARS-CoV-2 infection history were included. Study quality was assessed using a modified standardized scoring system. We fitted dynamic patterns of neutralizing antibody using a generalized additive model and a generalized additive mixed model. We also used linear regression model to conduct both univariate and multivariable analyses to explore the potential affecting factors on antibody levels. This study is registered with PROSPERO, CRD42022348636. Results7,343 studies were identified in the initial search, 50 were assessed for eligibility after removal of duplicates as well as inappropriate titles, abstracts and full-text review, and 48 studies (2,726 individuals, 5,670 samples) were included in the meta-analysis after quality assessment. The neutralization titer of people who infected with SARS-CoV-2 prototype strain peaked around 27 days (217.4, 95%CI: 187.0-252.9) but remained below the Omicron BA.5 protection threshold all the time after illness onset or confirmation. Furthermore, neither symptomatic infections nor asymptomatic infections could provide over 50% protection against Omicron BA.5 sub-lineage. It also showed that the clinical severity and the type of laboratory assays may significantly correlated with the level of neutralizing antibody. ConclusionsThis study provides a comprehensive mapping of the dynamic of neutralizing antibody against SARS-CoV-2 prototype strain induced by natural infection and compared the dynamic patterns between prototype and variant strains. It suggests that the protection probability provided by natural infection is limited. Therefore, timely vaccination is necessary for both previously infected symptomatic and asymptomatic individuals.
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BackgroundAn outbreak of COVID-19 caused by the SARS-CoV-2 Omicron BA.2 sublineage occurred in Shanghai, China from February to June 2022. The government organized multiple rounds of molecular test screenings for the entire population, providing a unique opportunity to capture the majority of subclinical infections and better characterize disease burden and the full spectrum of Omicron BA.2 clinical severity. MethodsUsing daily reports from the websites of the Shanghai Municipal Health Commission, we estimated the incidence of infections, severe/critical infections, and deaths to assess the disease burden. By adjusting for right censoring and Reverse Transcription-Polymerase Chain Reaction (RT{square}PCR) sensitivity, we provide estimates of clinical severity, including the infection fatality risk, symptomatic case fatality risk, and risk of developing severe/critical disease upon infection. FindingsFrom February 26 to June 30, 2022, the overall infection rate, severe/critical infection rate, and mortality rate were 2.74 (95% CI: 2.73-2.74) per 100 individuals, 6.34 (95% CI: 6.02-6.66) per 100,000 individuals and 2.42 (95% CI: 2.23-2.62) per 100,000 individuals, respectively. The severe/critical infection rate and mortality rate increased with age with the highest rates of 125.29 (95% CI: 117.05-133.44) per 100,000 and 57.17 (95% CI: 51.63-62.71) per 100,000 individuals, respectively, noted in individuals aged 80 years or older. The overall fatality risk and risk of developing severe/critical disease upon infection were 0.09% (95% CI: 0.08-0.10%) and 0.23% (95% CI: 0.20-0.25%), respectively. Having received at least one vaccine dose led to a 10-fold reduction in the risk of death for infected individuals aged 80 years or older. InterpretationUnder the repeated population-based screenings and strict intervention policies implemented in Shanghai, our results found a lower disease burden and mortality of the outbreak compared to other settings and countries, showing the impact of the successful outbreak containment in Shanghai. The estimated low clinical severity of this Omicron BA.2 epidemic in Shanghai highlight the key contribution of vaccination and availability of hospital beds to reduce the risk of death. FundingKey Program of the National Natural Science Foundation of China (82130093). Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed and Europe PMC for manuscripts published or posted on preprint servers after January 1, 2022 using the following query: ("SARS-CoV-2 Omicron") AND ("burden" OR "severity"). No studies that characterized the whole profile of disease burden and clinical severity during the Shanghai Omicron outbreak were found. One study estimated confirmed case fatality risk between different COVID-19 waves in Hong Kong; other outcomes, such as fatality risk and risk of developing severe/critical illness upon infection, were not estimated. One study based on 21 hospitals across the United States focused on Omicron-specific in-hospital mortality based on a limited sample of inpatients (565). In southern California, United States, a study recruited more than 200 thousand Omicron-infected individuals and estimated the 30-day risk of hospital admission, intensive care unit admission, mechanical ventilation, and death. None of these studies estimated infection and mortality rates or other indictors associated with disease burden. Overall, the disease burden and clinical severity of the Omicron BA.2 variant have not been fully characterized, especially in populations predominantly immunized with inactivated vaccines. Added value of this studyThe large-scale and multiround molecular test screenings conducted on the entire population during the Omicron BA.2 outbreak in Shanghai, leading to a high infection ascertainment ratio, provide a unique opportunity to capture the majority of subclinical infections. As such, our study provides a comprehensive assessment of both the disease burden and clinical severity of the SARS-CoV-2 Omicron BA.2 sublineage, which are especially lacking for populations predominantly immunized with inactivated vaccines. Implications of all the available evidenceWe estimated the disease burden and clinical severity of the Omicron BA.2 outbreak in Shanghai in February-June 2022. These estimates are key to properly interpreting field evidence and assessing the actual spread of Omicron in other settings. Our results also provide support for the importance of strategies to prevent overwhelming the health care system and increasing vaccine coverage to reduce mortality.
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Objective:To investigate the application value of Overlap guiding tube (OGT) in Overlap esophagojejunostomy of laparoscopic total gastrectomy.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 5 patients with gastric cancer who were admitted to Nanfang Hospital of Southern Medical University from June to July in 2021 were collected. There were 3 males and 2 females, aged from 48 to 61 years, with a median age of 54 years. Patients underwent laparoscopic total gastrectomy combined with OGT-assisted Overlap esophagojejunostomy. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) follow-up. Follow-up was conducted by outpatient examination and telephone interview to detect postoperative anastomotic stenosis and esophageal reflux up to September 2021. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(IQR) or M(range). Count data were represented as absolute numbers. Results:(1) Surgical situations: 5 patients underwent laparoscopic total gastrectomy combined with OGT-assisted Overlap esophagojejunostomy and D 2 lymph node dissection success-fully, achieving R 0 resection. There was no combined organ resection, intraoperative conversion to laparotomy or combined thoracotomy. There was no intraoperative conversion to other esophagoje-junostomy method either. The tumor diameter, length of surgical incision, the number of lymph nodes dissected, time of esophagojejunal anastomosis, time of digestive reconstruction, operation time, volume of intraoperative blood loss of 5 patients were 3.0(2.8)cm, 5.0(2.0)cm, 47.0(21.0), 21.0(5.0)minutes, 62.0(23.0)minutes, 295.0(75.0)minutes, and 50.0(60.0)mL, respectively. The anvil fork of linear stapler was successfully inserted into esophageal lumen by once operation in 4 cases of 5 patients and by twice operation in 1 case to complete the esophagojejunostomy. (2) Post-operative situations: the time to first out-of-bed activities, time to postoperative first anal flatus, time to postoperative initial liquid diet intake, time to postoperative initial semi-liquid diet intake, time to abdominal drainage tube removal, duration of postoperative hospital stay of 5 patients were 2.0(1.0)days, 3.0(2.0)days, 4.0(3.0)days, 6.0(3.0)days, 7.0(4.0)days, and 9.0(6.0)days, respectively. Results of postoperative pathological examination of 5 patients showed gastric adenocar-cinoma in all the 5 patients, with the TNM staging as stage pT2-4aN0M0. The esophageal surgical margin was negative in all cases, and the length of proximal margin from esophagus was 5.0(4.0)cm. None of the 5 patients developed anastomotic leakage, anastomotic bleeding or anastomotic stenosis. Two cases with mild pneumonia (Clavien-Dindo grade Ⅱ) were cured by conservative treatment such as anti-infection and expectoration promotion. There was no unplanned secondary surgery or perioperative death occurred to the 5 patients. (3) Follow-up: 5 patients were followed up for 3 months. None of the 5 patients developed anastomotic stenosis or esophageal reflux during the follow-up. Conclusion:OGT-assisted Overlap esophagojejunostomy of laparoscopic total gas-trectomy is safe and feasible, with good short-term effects.
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Evidence on vaccine-specific protection over time and boosting impact against the Delta variant across different clinical endpoints and age groups is urgently needed. To address this, we used a previously published model, combined with neutralization data for four vaccines - mRNA-1273, BNT162b2, NVX-CoV2373, and CoronaVac - to evaluate long-term dynamics of neutralizing antibody and to predict time-varying efficacy against the Delta variant by specific vaccine, age group, and clinical severity. We found that booster vaccination produces higher neutralization titers compared with titers observed following primary-series vaccination for all vaccines studied. We estimate the efficacies of mRNA-1273 and BNT162b2 against Delta variant infection to be 63.5% (95%CI: 51.4-67.3%) and 78.4% (95%CI: 72.2-83.5%), respectively, 14-30 days after the second dose, and that efficacies decreased to 36.0% (95%CI: 24.1-58.0%) and 38.5% (95%CI: 28.7-49.1%) 6-8 months later. After administration of booster doses, efficacies against the Delta variant would be 97.0% (95%CI: 96.4-98.5%) and 97.2% (95.7-98.1%). All four vaccines are predicted to provide good protection against severe illness from the Delta variant after both primary and booster vaccination. Long-term monitoring and surveillance of antibody dynamics and vaccine protection, as well as further validation of neutralizing antibody or other markers that can serve as correlates of protection against SARS-CoV-2 and its variants are needed to inform COVID-19 pandemic preparedness.
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BackgroundGenomic surveillance has shaped our understanding of SARS-CoV-2 variants, which have proliferated globally in 2021. Characterizing global genomic surveillance, sequencing coverage, the extent of publicly available genomic data coupled with traditional epidemiologic data can provide evidence to inform SARS-CoV-2 surveillance and control strategies. MethodsWe collected country-specific data on SARS-CoV-2 genomic surveillance, sequencing capabilities, public genomic data, and aggregated publicly available variant data. We divided countries into three levels of genomic surveillance and sequencing availability based on predefined criteria. We downloaded the merged and deduplicated SARS-CoV-2 sequences from multiple public repositories, and used different proxies to estimate the sequencing coverage and public availability extent of genomic data, in addition to describing the global dissemination of variants. FindingsSince the start of 2021, the COVID-19 global epidemic clearly featured increasing circulation of Alpha, which was rapidly replaced by the Delta variant starting around May 2021 and reaching a global prevalence of 96.6% at the end of July 2021. SARS-CoV-2 genomic surveillance and sequencing availability varied markedly across countries, with 63 countries performing routine genomic surveillance and 79 countries with high availability of SARS-CoV-2 sequencing. Less than 3.5% of confirmed SARS-CoV-2 infections were sequenced globally since September 2020, with the lowest sequencing coverage in the WHO regions of Eastern Mediterranean, South East Asia, and Africa. Across different variants, 28-52% of countries with explicit reporting on variants shared less than half of their variant sequences in public repositories. More than 60% of demographic and 95% of clinical data were absent in GISAID metadata accompanying sequences. InterpretationOur findings indicated an urgent need to expand sequencing capacity of virus isolates, enhance the sharing of sequences, the standardization of metadata files, and supportive networks for countries with no sequencing capability. Research in context Evidence before this studyOn September 3, 2021, we searched PubMed for articles in any language published after January 1, 2020, using the following search terms: ("COVID-19" OR "SARS-CoV-2") AND ("Global" OR "Region") AND ("genomic surveillance" OR "sequencing" OR "spread"). Among 43 papers identified, few papers discussed the global diversity in genomic surveillance, sequencing, public availability of genomic data, as well as the global spread of SARS-CoV-2 variants. A paper from Furuse employed the publicly GISAID data to evaluate the SARS-CoV-2 sequencing effort by country from the perspectives of "fraction", "timeliness", and "openness". Another viewpoint paper by Case Western Reserve Universitys team discussed the impediments of genomic surveillance in several countries during the COVID-19 pandemic. The paper as reported by Campbell and colleagues used the GISAID data to present the global spread and estimated transmissibility of recently emerged SARS-CoV-2 variants. We also found several studies that reported the country-level genomic surveillance and spread of variants. To our knowledge, no research has quantitatively depicted the global SARS-CoV-2 genomic surveillance, sequencing ability, and public availability extent of genomic data. Added value of this studyThis study collected country-specific data on SARS-CoV-2 genomic surveillance, sequencing capabilities, public genomic data, and aggregated publicly available variant data as of 20 August 2021. We found that genomic surveillance strategies and sequencing availability is globally diverse. Less than 3.5% of confirmed SARS-CoV-2 infections were sequenced globally since September 2020. Our analysis of publicly deposited SARS-CoV-2 sequences and officially reported number of variants implied that the public availability extent of genomic data is low in some countries, and more than 60% of demographic and 95% of clinical data were absent in GISAID metadata accompanying sequences. We also described the pandemic dynamics shaped by VOCs. Implications of all the available evidenceOur study provides a landscape for global sequencing coverage and public availability extent of sequences, as well as the evidence for rapid spread of SRAS-CoV-2 variants. The pervasive spread of Alpha and Delta variants further highlights the threat of SARS-CoV-2 mutations despite the availability of vaccines in many countries. It raised an urgent need to do more work on defining the ideal sampling schemes for different purposes (e.g., identifying new variants) with an additional call to share these data in public repositories to allow for further rapid scientific discovery.
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The emergence of SARS-CoV-2 variants have raised concerns over the protective efficacy of the current generation of vaccines, and it remains unclear to what extent, if any, different variants impact the efficacy and effectiveness of various SARS-CoV-2 vaccines. We systematically searched for studies of SARS-CoV-2 vaccine efficacy and effectiveness, as well as neutralization data for variants, and used a previously published statistical model to predict vaccine efficacy against variants. Overall, we estimate the efficacy of mRNA-1273 and ChAdOx1 nCoV-19 against infection caused by the Delta variant to be 25-50% lower than that of prototype strains. The predicted efficacy against symptomatic illness of the mRNA vaccines BNT162b2 and mRNA-1273 are 95.1% (UI: 88.4-98.1%) and 80.8% (60.7-92.3%), respectively, which are higher than that of adenovirus-vector vaccines Ad26.COV2.S (44.8%, UI: 29.8-60.1%) and ChAdOx1 nCoV-19 (41.1%, 19.8-62.8%). Taken together, these results suggest that the development of more effective vaccine strategies against the Delta variant may be needed. Finally, the use of neutralizing antibody titers to predict efficacy against variants provides an additional tool for public health decision making, as new variants continue to emerge.
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BackgroundImmunity after SARS-CoV-2 infection or vaccination has been threatened by recently emerged SARS-CoV-2 variants. A systematic summary of the landscape of neutralizing antibodies against emerging variants is needed. MethodsWe systematically searched PubMed, Embase, Web of Science, and 3 pre-print servers for studies that evaluated neutralizing antibodies titers induced by previous infection or vaccination against SARS-CoV-2 variants and comprehensively collected individual data. We calculated lineage-specific GMTs across different study participants and types of neutralization assays. FindingsWe identified 56 studies, including 2,483 individuals and 8,590 neutralization tests, meeting the eligibility criteria. Compared with lineage B, we estimate a 1.5-fold (95% CI: 1.0-2.2) reduction in neutralization against the B.1.1.7, 8.7-fold (95% CI: 6.5-11.7) reduction against B.1.351 and 5.0-fold (95% CI: 4.0-6.2) reduction against P.1. The estimated neutralization reductions for B.1.351 compared to lineage B were 240.2-fold (95% CI: 124.0-465.6) reduction for non-replicating vector platform, 4.6-fold (95% CI: 4.0-5.2) reduction for RNA platform, and 1.6-fold (95% CI: 1.2-2.1) reduction for protein subunit platform. The neutralizing antibodies induced by administration of inactivated vaccines and mRNA vaccines against lineage P.1 were also remarkably reduced by an average of 5.9-fold (95% CI: 3.7-9.3) and 1.5-fold (95% CI: 1.2-1.9). InterpretationOur findings indicate that the antibody response established by natural infection or vaccination might be able to effectively neutralize B.1.1.7, but neutralizing titers against B.1.351 and P.1 suffered large reductions. Standardized protocols for neutralization assays, as well as updating immune-based prevention and treatment, are needed. FundingChinese National Science Fund for Distinguished Young Scholars Research in contextO_ST_ABSEvidence before this studyC_ST_ABSSeveral newly emerged SARS-CoV-2 variants have raised significant concerns globally, and there is concern that SARS-CoV-2 variants can evade immune responses that are based on the prototype strain. It is not known to what extent do emerging SARS-CoV-2 variants escape the immune response induced by previous infection or vaccination. However, existing studies of neutralizing potency against SARS-CoV-2 variants are based on limited numbers of samples and lack comparability between different laboratory methods. Furthermore, there are no studies providing whole picture of neutralizing antibodies induced by prior infections or vaccination against emerging variants. Therefore, we systematically reviewed and quantitively synthesized evidence on the degree to which antibodies from previous SARS-CoV-2 infection or vaccination effectively neutralize variants. Added value of this studyIn this study, 56 studies, including 2,483 individuals and 8,590 neutralization tests, were identified. Antibodies from natural infection or vaccination are likely to effectively neutralize B.1.1.7, but neutralizing titers against B.1.351 and P.1 suffered large reductions. Lineage B.1.351 escaped natural-infection-mediated neutralization the most, with GMT of 79.2 (95% CI: 68.5-91.6), while neutralizing antibody titers against the B.1.1.7 variant were largely preserved (254.6, 95% CI: 214.1-302.8). Compared with lineage B, we estimate a 1.5-fold (95% CI: 1.0-2.2) reduction in neutralization against the B.1.1.7, 8.7-fold (95% CI: 6.5-11.7) reduction against B.1.351 and 5.0-fold (95% CI: 4.0-6.2) reduction against P.1. The neutralizing antibody response after vaccinating with non-replicating vector vaccines against lineage B.1.351 was worse than responses elicited by vaccines on other platforms, with levels lower than that of individuals who were previously infected. The neutralizing antibodies induced by administration of inactivated vaccines and mRNA vaccines against lineage P.1 were also remarkably reduced by an average of 5.9-fold (95% CI: 3.7-9.3) and 1.5-fold (95% CI: 1.2-1.9). Implications of all the available evidenceOur findings indicate that antibodies from natural infection of the parent lineage of SARS-CoV-2 or vaccination may be less able to neutralize some emerging variants, and antibody-based therapies may need to be updated. Furthermore, standardized protocols for neutralizing antibody testing against SARS-CoV-2 are needed to reduce lab-to-lab variations, thus facilitating comparability and interpretability across studies.
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Nanosecond pulsed electric field (nsPEF) is a novel, nonthermal, and minimally invasive modality that can ablate solid tumors by inducing apoptosis. Recent animal experiments show that nsPEF can induce the immunogenic cell death of hepatocellular carcinoma (HCC) and stimulate the host's immune response to kill residual tumor cells and decrease distant metastatic tumors. nsPEF-induced immunity is of great clinical importance because the nonthermal ablation may enhance the immune memory, which can prevent HCC recurrence and metastasis. This review summarized the most advanced research on the effect of nsPEF. The possible mechanisms of how locoregional nsPEF ablation enhances the systemic anticancer immune responses were illustrated. nsPEF stimulates the host immune system to boost stimulation and prevail suppression. Also, nsPEF increases the dendritic cell loading and inhibits the regulatory responses, thereby improving immune stimulation and limiting immunosuppression in HCC-bearing hosts. Therefore, nsPEF has excellent potential for HCC treatment.
Subject(s)
Animals , Carcinoma, Hepatocellular/therapy , Cell Line, Tumor , Immunity , Liver Neoplasms/therapy , Neoplasm Recurrence, LocalABSTRACT
Objective:To analyze the interim clinical efficacy of laparoscopic and open distal gastrectomy for gastric cancer in elderly patients.Methods:The prospective randomized controlled study was conducted. The clinicopathological data of 102 patients aged ≥65 years who underwent distal gastrectomy for gastric cancer in the Nanfang Hospital of Southern Medical University from September 2014 to May 2018 were collected. After excluding 6 patients, 96 patients were finally included. Based on random number table, patients were allocated into two groups. Patients undergoing laparoscopic distal gastrectomy were allocated into laparoscopic group, and patients undergoing open distal gastrectomy were allocated into open group, respectively. Obser-vation indicators: (1) grouping situations of the enrolled patients; (2) intraoperative situations; (3) postoperative situations; (4) follow-up. Follow-up using outpatient examination and telephone interview was conducted to detect complications in the postoperative 30 days up to July 2018. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M( P25, P75) or M(range), and comparison between groups was analyzed using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Comparison of ordinal data was analyzed using the non-parameter Mann-Whitney U test. Results:(1) Grouping situations of the enrolled patients: a total of 96 patients were selected for eligibility. There were 66 males and 30 females, aged from 65 to 85 years, with a median age of 69 years. There were 49 of 96 patients in the laparoscopic group and 47 patients in the open group. (2) Intraoperative situations: patients in the two groups underwent distal gastrectomy successfully with D 2 lymphadenectomy, without intra-operative conversion to laparotomy. The volume of intraoperative blood loss and surgical incision length were 50 mL(50 mL,100 mL) and (7.1±1.7)cm for the laparoscopic group, respectively, versus 100 mL(100 mL,200 mL) and (19.1±1.7)cm for the open group, showing significant differences between the two groups ( Z=?3.779, t=?34.880, P<0.05) . (3) Postoperative situations: the number of lymph node dissected, time to postoperative initial out-of-bed activities, time to postoperative first flatus, time to postoperative first liquid food intake, time to postoperative first semi-liquid food intake, time to drainage tube removal, duration of postoperative hospital stay were 49(35,62), 1.9 days(1.3 days,2.9 days), 2.6 days(2.2 days,2.9 days), 3.4 days(2.7days,4.0 days), 5.9 days(4.7 days,7.7 days), 4.9 days(3.5 days,6.8 days), 7.7 days(6.7 days,8.9 days) for the laparoscopic group, respectively, versus 40(27,51), 2.5 days (1.8 days,3.3 days), 2.6 days(2.2 days,2.9 days), 3.9 days(2.9 days,5.7 days), 4.9 days(3.9 days, 5.9 days), 6.3 days(4.7 days,8.9 days), 8.7 days(6.9 days,11.7 days), showing significant differences between the two groups ( Z=?2.354, ?2.210, ?2.743, ?2.474, ?2.906, ?2.503, ?2.359, P<0.05). (4) Follow-up: patients in the two groups received 30 days of follow-up. During the follow-up, 8 patients in the laparoscopic group had postoperative complications, including 1 case with Clavien-Dindo grade Ⅰ complications, 7 cases with Clavien-Dindo grade Ⅱ complications, and no patient with Clavien-Dindo grade Ⅲ complications. Thirteen patients in the open group had postoperative complications, including 2 cases with Clavien-Dindo grade Ⅰ complications, 10 cases with Clavien-Dindo grade Ⅱ complications, and 1 case with Clavien-Dindo grade Ⅲ complications. There was no significant difference in the above indicators between the two groups ( χ2=1.135, 1.973, 1.054, P>0.05). The overall complication rate was 16.3%(8/49) and 27.7%(13/47) for the laparoscopic group and open group, respectively, showing no significant difference between the two groups ( χ2=1.803, 99.7% confidence interval as ?∞ to 2.4%, P>0.05). The upper limit of 99.7% confidence interval was less than non-inferiority level of 15%, interim analysis of which showed that the complication rate of the laparoscopic group was non-inferior to the open group. Conclusion:For elderly patients undergoing laparoscopic or open distal gastrectomy for gastric cancer, laparoscopic surgery does not increase intraoperative or postoperative complications, and has advantages of minimally invasiveness, fine operation, quicker recovery, and shorter hospital stay. Registry: this study was registered at clinicaltrials.gov in United States, with the registry number of NCT02246153.
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Pulsed electric field(PEF) provides high-energy instantaneous pulse and release energy to myocardial cell membrane, resulting in irreversible electroporation and causes myocardial cell contents leakage, destruction of intracellular homeostasis, cell death, and slight inflammatory response. PEF as non-thermal energy promotes the design and application of arrhythmia ablation catheter to enter a new stage. There are currently limited clinical studies that have proved the safety and effectieness of Farawave PEF catheter, PVAC GOLD PEF catheter, Lattice-tip Sphere-9 PEF and radiofrequency (RF) catheter used for atrial fibrillation ablation, but still need further discussion. The research of atrial fibrillation ablation with PEF is under study in China. In this paper, the design and application of PEF ablation for tachyarrhythmia are reviewed.
Subject(s)
Humans , Atrial Fibrillation/surgery , Catheter Ablation , Catheters , Pulmonary Veins/surgery , TachycardiaABSTRACT
BackgroundCOVID-19 vaccine prioritization and allocation strategies that maximize health benefit through efficient use of limited resources are urgently needed. We aimed to provide global, regional, and national estimates of target population sizes for COVID-19 vaccination to inform country-specific immunization strategies on a global scale. MethodsBased on a previous study of international allocation for pandemic COVID-19 vaccines, we classified the entire world population into eleven priority groups. Information on priority groups was derived from a multi-pronged search of official websites, media sources and academic journal articles. The sizes of different priority groups were projected for 194 countries globally. ResultsOverall, the size of COVID-19 vaccine recipient population varied markedly by goals of the vaccination program and geography. The general population aged <60 years without any underlying condition accounts for the majority of the total population (5.2 billion people, 68%), followed by 2.3 billion individuals at risk of severe disease, and 246.9 million essential workers which are critical to maintaining a functional society. Differences in the demographic structure, presence of underlying conditions, and number of essential workers led to highly variable estimates of target populations both at the WHO region and country level. In particular, Europe has the highest share of essential workers (6.8%) and the highest share of individuals with underlying conditions (37.8%), two priority categories to maintain societal functions and reduce severe burden. In contrast, Africa has the highest share of healthy adults, school-age individuals, and infants (77.6%), which are the key groups to target to reduce community transmission. InterpretationThe sizeable distribution of target groups on a country and regional bases underlines the importance of equitable and efficient vaccine prioritization and allocation globally. The direct and indirect benefits of COVID-19 vaccination should be balanced by considering local differences in demography and health.
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BackgroundA rapidly increasing number of serological surveys for anti-SARS-CoV-2 antibodies have been reported worldwide. A synthesis of this large corpus of data is needed. PurposeTo evaluate the quality of serological studies and provide a global picture of seroprevalence across demographic and occupational groups, and to provide guidance for conducting better serosurveys. Data sourcesWe searched PubMed, Embase, Web of Science, and 4 pre-print servers for English-language papers published from December 1, 2019 to September 25, 2020. Study selectionSerological studies evaluating SARS-CoV-2 seroprevalence in humans. Data extractionTwo investigators independently extracted data from studies. Data SynthesisMost of 230 serological studies, representing tests in >1,400,000 individuals, identified were of low quality based on a standardized study quality scale. In the 51 studies of higher quality, high-risk healthcare workers had higher seroprevalence of 17.1% (95% CI: 9.9-24.4%), compared to low-risk healthcare workers and general population of 5.4% (0.7-10.1%) and 5.3% (4.2-6.4%). Seroprevalence varied hugely across WHO regions, with lowest seroprevalence of general population in Western Pacific region (1.7%, 0.0-5.0%). Generally, the young (<20 years) and the old ([≥]65 years) were less likely to be seropositive compared to middle-aged (20-64 years) populations. Seroprevalence correlated with clinical COVID-19 reports, with pooled average of 7.7 (range: 2.0 to 23.1) serologically-detected-infections per confirmed COVID-19 case. LimitationsSome heterogeneity cannot be well explained quantitatively. ConclusionsThe overall quality of seroprevalence studies examined was low. The relatively low seroprevalence among general populations suggest that in most settings, antibody-mediated herd immunity is far from being reached. Given the relatively narrow range of estimates of the ratio of serologically-detected infections to confirmed cases across different locales, reported case counts may help provide insights into the true proportion of the population infected. Primary Funding sourceNational Science Fund for Distinguished Young Scholars (PROSPERO: CRD42020198253).
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The pandemic of novel coronavirus disease 2019 (COVID-19) began in Wuhan, China, where a first wave of intense community transmission was cut short by interventions. Using multiple data source, we estimated the disease burden and clinical severity of COVID-19 by age in Wuhan from December 1, 2019 to March 31, 2020. We adjusted estimates for sensitivity of laboratory assays and accounted for prospective community screenings and healthcare seeking behaviors. Rates of symptomatic cases, medical consultations, hospitalizations and deaths were estimated at 796 (95%CI: 703-977), 489 (472-509), 370 (358-384), and 36.2 (35.0-37.3) per 100,000 persons, respectively. The COVID-19 outbreak in Wuhan had higher burden than the 2009 influenza pandemic or seasonal influenza, and that clinical severity was similar to that of the 1918 influenza pandemic. Our comparison puts the COVID-19 pandemic into context and could be helpful to guide intervention strategies and preparedness for the potential resurgence of COVID-19.
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BackgroundSeveral parameters driving the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain unclear, including age-specific differences in infectivity and susceptibility, and the contribution of inapparent infections to transmission. Robust estimates of key time-to-event distributions remain scarce as well. MethodsWe collected individual records for 1,178 SARS-CoV-2 infected individuals and their 15,648 contacts identified by contact tracing and monitoring over the period from January 13 to April 02, 2020 in Hunan Province, China. We provide descriptive statistics of the characteristics of cases and their close contacts; we fitted distributions to time-to-key-events distributions and infectiousness profile over time; and we used generalized linear mixed model to estimate risk factors for susceptibility and transmissibility of SARS-CoV-2. ResultsWe estimated the mean serial interval at 5.5 days (95%CI -5.0, 19.9) and the mean generation time at 5.5 days (95%CI 1.7, 11.6). The infectiousness was estimated to peak 1.8 days before symptom onset, with 95% of transmission events occurring between 7.6 days before and 7.3 days after the date of symptom onset. The proportion of pre-symptomatic transmission was estimated to be 62.5%. We estimated that at least 3.5% of cases were generated asymptomatic individuals. SARS-CoV-2 transmissibility was not significantly different between working-age adults (15-59 years old) and other age groups (0-14 years old: p-value=0.16; 60 years and over: p-value=0.33), whilst susceptibility to SARS-CoV-2 infection was estimated to increase with age (p-value=0.03). In addition, transmission risk was higher for household contacts (p-value<0.001), decreased for higher generations within a cluster (second generation: odds ratio=0.13, p-value<0.001; generations 3-4: odds ratio=0.05, p-value<0.001, relative to generation 1), and decreased for infectors with a larger number of contacts (p-value=0.04). InterpretationOur findings warn of the possible relevant contribution of children to SARS-CoV-2 transmission. When lockdown interventions are in place, we found that odds of transmission are highest in the household setting but, with the relaxation of interventions, other settings (including schools) could bear a higher risk of transmission. Moreover, the estimated relevant fraction of pre-symptomatic and asymptomatic transmission highlight the importance of large-scale testing, contact tracing activities, and the use of personnel protective equipment during the COVID-19 pandemic.
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We conducted two surveys to evaluate the health-seeking behaviors of individuals with acute respiratory infections (ARI) during the COVID-19 outbreak in Wuhan, China. Among 351 participants reporting ARI (10.3%, 351/3,411), 36.5% sought medical assistance. Children were more likely to seek medical assistance than other age groups (66.1% vs. 28.0%-35.1%).
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BackgroundThe COVID-19 epidemic originated in Wuhan City of Hubei Province in December 2019 and has spread throughout China. Understanding the fast evolving epidemiology and transmission dynamics of the outbreak beyond Hubei would provide timely information to guide intervention policy. MethodsWe collected individual information on 8,579 laboratory-confirmed cases from official publically sources reported outside Hubei in mainland China, as of February 17, 2020. We estimated the temporal variation of the demographic characteristics of cases and key time-to-event intervals. We used a Bayesian approach to estimate the dynamics of the net reproduction number (Rt) at the provincial level. ResultsThe median age of the cases was 44 years, with an increasing of cases in younger age groups and the elderly as the epidemic progressed. The delay from symptom onset to hospital admission decreased from 4.4 days (95%CI: 0.0-14.0) until January 27 to 2.6 days (0.0-9.0) from January 28 to February 17. The mean incubation period was estimated at 5.2 days (1.8-12.4) and the mean serial interval at 5.1 days (1.3-11.6). The epidemic dynamics in provinces outside Hubei was highly variable, but consistently included a mix of case importations and local transmission. We estimate that the epidemic was self-sustained for less than three weeks with Rt reaching peaks between 1.40 (1.04-1.85) in Shenzhen City of Guangdong Province and 2.17 (1.69-2.76) in Shandong Province. In all the analyzed locations (n=10) Rt was estimated to be below the epidemic threshold since the end of January. ConclusionOur findings suggest that the strict containment measures and movement restrictions in place may contribute to the interruption of local COVID-19 transmission outside Hubei Province. The shorter serial interval estimated here implies that transmissibility is not as high as initial estimates suggested.
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The prognosis of advanced gastric cancer (AGC) is extremely poor. There is no standard and satisfactory treatment strategy for AGC. In clinical practice, some AGC patients can achieve long-term survival. However, it is not clear which type of AGC can benefit the best in specific treatment mode. Because of the high heterogeneity of AGC, it is particularly important to further dig out more significant beneficiary groups. Therefore, experts put forward the classification based on the biological characteristics and the surgery-oriented classification to predict and select patients who benefit from conversion therapy. While for immunotherapy, the biomarkers, molecular subtyping and potential combination strategies are explored to break through its bottleneck in the treatment in AGC that only certain individuals benefit from it. The authors review the research progress in treatment for advanced gastric cancer.
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Objective:To study the clinical manifestations, diagnosis and treatment of primary hyperparathyroidism (PHPT) in pregnancy.Methods:This study involved six pregnant patients with PHPT who were admitted to Ruijin Hospital of Shanghai Jiao Tong University from August 2014 to November 2019. Their clinical manifestations, treatment strategies (multidisciplinary consultation with departments including Obstetrics, Endocrinology, Neonatology, General Surgery, Anesthesiology and Intensive Care Unit), maternal complications and maternal and infant outcomes were described and retrospectively analyzed.Results:(1) The median age of the six patients was 34(23-38) years old. PHPT was diagnosed in one case before pregnancy, four in the second or third trimester and one after delivery. The main clinical manifestations of four cases were nausea, vomiting, anorexia and other non-specific symptoms. Anemia was the most common maternal complication (five cases). Other complications included hypercalcemia crisis with renal failure (one case), multiple bone destruction and osteoporosis (one case). The median levels of serum calcium, parathyroid hormone and 25-hydroxyvitamin D were 3.08 (2.84-4.21) mmol/L, 216.7(93.1-2 603.6) ng/L and 29.66 (13.50-90.24) nmol/L, respectively. Results of parathyroid ultrasonography showed all patients had hypoechoic focus. Four cases underwent routine parathyroid radionuclide imaging showing abnormal radioactive concentration areas. (2) Obstetricians initiated the multidisciplinary team (MDT) for all patients to determine the treatment plans after communication with the patients and their families. One case received surgical treatment five months after delivery. Three cases received surgical treatment in the second trimester and among them, one terminated the pregnancy in the second trimester and the other two continued and achieved good pregnancy outcomes. Two cases underwent surgical treatment after giving up pregnancy and induced abortion. Postoperative pathology revealed that five cases were isolated parathyroid adenoma and one was parathyroid carcinoma. All of the patients were followed up and no abnormal serum calcium was reported. (3) One newborn had hypocalcemic convulsions one month after birth and was recovered by intravenous calcium supplementation. The newborn was followed up and the serum calcium level was normal so far. The other two neonates had normal serum calcium during follow-ups, but one of them was diagnosed with autism at the age of four and is now undergoing rehabilitation treatment.Conclusions:Pregnancy complicated by PHPT may lead to serious maternal and infant complications. MDT consultation ensures timely diagnosis, comprehensive treatment for the patients and better pregnancy outcomes.
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OBJECTIVE@#To evaluate the short-term efficacy and cosmetic effect of dual-port laparoscopic distal gastrectomy (DPLDG) for gastric cancer.@*METHODS@#Thirty consecutive patients underwent DPLDG at the Department of General Surgery, Nanfang Hospital from November 2016 to August 2018.@*INCLUSION CRITERIA@#(1) age of 18 to 75 years; (2) primary gastric adenocarcinoma confirmed pathologically by endoscopic biopsy; (3) tumor located at middle-low stomach and planned for distal gastrectomy; (4) cT1b-2N0-1M0 at preoperative staging; (5) tumor diameter ≤3 cm; (6) US Eastern Cancer Cooperative Group(ECOG) score 0 to 1 points; (7) American Society of Anesthesiologists grade I to II; (8) perioperative management based on enhanced recovery after surgery (ERAS) principle.@*EXCLUSION CRITERIA@#previous upper abdominal surgery (except laparoscopic cholecystectomy), history of other malignant disease, and body mass index ≥30 kg/m². A self-developed single-incision, multiport, laparoscopic surgery Trocar (Surgaid Medical, Xiamen, China, comprising 3 channels for observation, main surgeon and assistant surgeon) was placed through a 3-4 cm incision under or at the left side of the umbilicus. An additional 5 mm Trocar was inserted under the rib margin of the right clavicle to serve as the secondary operating hole and the position of the drainage tube. The liver was suspended to expose the surgical field clearly. Surgical procedure was as follows: conventional laparoscopic instruments were used. After entering the omental sac, dissection was performed along the transverse colon to the spleen flexure. Left gastroepiploic vessels were identified and then ligated at the root. No.4sb lymph nodes were dissected. The No.4d lymph nodes were dissected along the greater curvature of the stomach. Then the dissection was continued rightward to the hepatic flexure to separate mesogastrium and mesocolon. The right gastroepiploic artery was ligated at the root to allow the removal of No.6 lymph nodes. The duodenal bulb was transacted by liner stapler, the right gastric artery was ligated at the root and the No.5 lymph nodes were removed. Peritoneal trunk, common hepatic artery, splenic artery and left gastric artery and vein in posterior pancreatic space at upper pancreas were separated, then left gastric vessels were ligated, and No.9, No.8a, No.11p and No.7 lymph nodes were dissected. The left side wall of portal vein was exposed and No.12a lymph nodes were removed. No.1 and No.3 lymph nodes were dissected along the lesser curvature. The stomach corpus was transacted by liner stapler at 4-5 cm proximal end of the tumor. Roux-en-Y anastomosis or Billroth II anastomosis was performed in the cavity. A drainage tube was placed near the gastrojejunal anastomosis through the right upper abdomen secondary operating hole. Postoperative short-term efficacy (operation time, blood loss, 5-port conversion rate, open conversion rate, number of retrieved lymph nodes, time to postoperative first flatus, time to first soft diet intake, time to removal of drainage tube, postoperative hospital stay, postoperative analgesics use, and postoperative 30-day complication rate) and cosmetic scale (questionnaire: degree of satisfaction with scar, description of scar, grade of scar; total score ranged from the lowest 3 to the highest 24; the higher the better) were evaluated in all 30 patients.@*RESULTS@#No serious complication and death were observed intraoperatively. The mean operative time was (197.8±46.9) minutes. The median blood loss was 30 ml (quartile 31.25 ml). The mean number of retrieved lymph node was 38.7±14.1. Five-port conversion rate was 3.3% (1/30), and no open conversion occurred. Mean time to postoperative first flatus, time to first soft diet intake, time to removal of drainage tube and postoperative hospital stay were (45.3±18.9) hours, (87.6±35.6) hours, (101.8±58.0) hours and (6.1±2.1) days, respectively. Twenty-four (80%) of patients had no additional analgesics use. The postoperative complication rate within 30 days was 16.7% (5/30). Postoperative overall cosmetic score was 22.1±1.3, and cosmetic score of 96.7%(29/30) of patients was 18 to 24.@*CONCLUSION@#DPLDG is safe and feasible with advantages of faster postoperative recovery, reducing pain and better cosmetic outcomes.
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Humans , Adenocarcinoma , Pathology , General Surgery , China , Feasibility Studies , Gastrectomy , Methods , Gastroenterostomy , Laparoscopy , Methods , Lymph Node Excision , Retrospective Studies , Stomach Neoplasms , Pathology , General Surgery , Treatment OutcomeABSTRACT
Objective To investigate the perinatal outcomes after elective neurosurgery in pregnant women complicated by space-occupying lesions in saddle area.Methods Clinical data were retrospectively collected and analyzed from five gravidas with space-occupying lesions in saddle area,who underwent neurosurgery at Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from June 2017 to February 2018,including gestational age,perioperative management,surgical procedures,postoperative complications,pregnancy outcomes and pathological results.Results (1) Progressively deteriorated impaired vision was the chief complaint of all five patients.Space-occupying lesions in saddle area were detected by cranial MRI (plain scan).The surgical indication was clear as there was compression on optic nerve and a risk of blindness due to optic nerve atrophy,Two patients were operated in the third trimester and three in the second trimester.Postoperative pathology showed there were two cases with meningioma,two with pituitary macro adenoma and one with abscess of pituitary.Only one patient had mild postoperative cerebrospinal fluid rhinorrhea,which was improved three months later,and no complications were reported in the other four cases.All five patients had obvious improvement of vision after surgical intervention and no relapse was reported during a follow-up of 4-12 months.(2) Four gravidas continued their pregnancies to full or nearly full term,among which three underwent cesarean section due to obstetrical indications (one breech pregnancy,one twin pregnancy with scarred uterus and one complicated by hypertensive diseases of pregnancy with poor blood pressure control) and one delivered vaginally.Postpartum involution of the uterus was well in all of the four cases 42 d after delivery.The women with pituitary abscess terminated the pregnancy due to intraamniotic injection of ethacridine lactate at 20 weeks of gestation.Five neonates were all born with Apgar scores of 10 at 1,5 and 10 min without any visible defects at birth and all grew and developed normally at 4-12 months after birth.Conclusions For gravidas with space-occupying lesions in saddle area,it is necessary to weigh the pros and cons and choose an individualized treatment plan.Resection of saddle area lesions in the second or third trimester backed by a multidisciplinary team is a safe and feasible procedure if postponing the operation until delivery may cause irreversible or even life-threatening consequences.