ABSTRACT
Background During dental procedures, critical parameters, such as cooling condition, speed of the rotary dental turbine (handpiece), and distance and angle from pollution sources, were evaluated for transmission risk of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), simulated by spiking in a plasmid encoding a modified viral spike protein, HexaPro (S6P), in droplets and aerosols.Methods To simulate routine operation in dental clinics, dental procedures were conducted on a dental manikin within a digital dental unit, incorporating different dental handpiece speeds and cooling conditions. The tooth model was immersed in Coomassie brilliant blue dye and was pre-coated with 100 µL water spiked-in with S6P-encoding plasmid. Furthermore, the manikin was surrounded by filter papers and Petri dishes positioned at different distances and angles. Subsequently, the filter papers and Petri dishes were collected to evaluate the aerosol splash points and the viral load of S6P-encoding plasmid in aerosols and splatters generated during the dental procedure.Results Aerosol splashing generated a localized pollution area extended up to 60 cm, with heightened contamination risks concentrated within a 30 cm radius. Significant differences in aerosol splash points and viral load by different turbine handpiece speeds under any cooling condition (P < 0.05) were detected. The highest level of aerosol splash points and viral load were observed when the handpiece speed was set at 40,000 rpm. Conversely, the lowest level of aerosol splash point and viral load were found at a handpiece speed of 10,000 rpm. Moreover, the aerosol splash points with higher viral load were more prominent in the positions of the operator and assistant compared to other positions. Additionally, the position of the operator exhibited the highest viral load among all positions.Conclusions To minimize the spread of aerosol and virus in clinics, dentists are supposed to adopt the minimal viable speed of a dental handpiece with limited cooling water during dental procedures. In addition, comprehensive personal protective equipment is necessary for both dental providers and dental assistants.
Subject(s)
Severe Acute Respiratory Syndrome , Nevus, Blue , Tooth DiseasesABSTRACT
Purpose： To analyze the clinical manifestations of perinatal pregnant women with pulmonary embolism(PE) and improve the understanding of maternal PE disease. Methods：We retrospectively reviewed maternities diagnosed with PE in a maternity and infant hospital between July 2018 and June 2020. Patients were divided into different groups according to risk stratification. Clinical data were collected and statistically analyzed by SPSS. Results: A total of 49 patients, with an average age of (32.31±4.17) years at delivery were clarified into low-risk group (28 patients, 57.1%) and medium-risk group (21 patients, 42.9%). The medium-risk group had a significant higher serum level of TnI (0.0052±0.0073 ng/ml) compared with low-risk group (0.0009±0.0013 ng/ml). Although d-dimer level (5.1±3.6 mg/l) of selected patients were higher than normal range at the time of admitting, a significant increasing trend was still observed when diagnosed with PE (p=0.012 in low-risk group, p=0.005 in medium-risk group). The location of thrombosis distributed mainly in right lung (28(57.1%)) and lower field of lung (32(65.3%)) according to CTA image, while 5 cases of right ventricular enlargement were limited in medium-risk group. While 87.8% of patients were asymptomatic. The frequencies of PE in Febraury 2020 and March 2020 were higher compared to any other month, which was in accordance with the first episode period of COVID-19 in China. Conclusion: Perinatal PE is frequently found in elderly pregnant women, with a more benign clinical presentation compared with reported data. Dynamic monitoring of d-dimer may have more clinical value for early identification of perinatal PE.
Subject(s)
Pulmonary Embolism , Thrombosis , Cardiomegaly , COVID-19ABSTRACT
Background Community clustering is one of the main features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, few studies have been conducted on the clinical characteristics and clinical outcome of clustered cases and sporadic cases with COVID-19. Methods We recruited 41 community clusters confirmed with SARS-CoV-2 infection compared with 49 sporadic cases in Zhejiang Province from 19 January 2020 to 9 June 2020. Clinical data were collected to evaluate the clinical outcome and characteristics of community clusters. Results Compared to sporadic cases, clustered cases had significantly lower Acute Physiology and Chronic Health Evaluation II (APACHE II) score {5.0 [interquartile range (IQR), 2.0–7.5] vs. 7.0 [IQR, 4.0–12.5];P = 0.005}, less members in intensive care unit (ICU) (6 [14.6%] vs. 18 [36.7%];P = 0.018), and shorter time of viral shedding in fecal samples (18.5 [IQR, 17.0–28.3] vs. 32.0 [IQR, 24.3–35.5];P = 0.002). Univariable logistic regression revealed that older age (odds ratios 1.078, 95% confidence intervals 1.007–1.154, per year increase;p = 0.032), high APACHE II score (3.171, 1.147–8.76;P = 0.026), elevated interleukin-2 levels (3.078, 1.145–8.279;P = 0.026) were associated with ICU admission of clustered cases. Conclusions Compared to sporadic cases, clustered cases exhibited milder disease severity and a better clinical outcome, which may be closely related to the management of early detection, early diagnosis, early treatment and early isolation of COVID-19.
ABSTRACT
Background: To describe the clinical characteristics and the time of nucleic acid turning negative in patients with common type Corona Virus Disease 2019(COVID-19) pneumonia and analyze the treatment time and prognostic factors.Methods: It’s a retrospective analysis of 72 cases of common type COVID-19 pneumonia diagnosed by nucleic acid test and Computed tomography (CT).Results: The average time of nucleic acid test turning negative is 17.37±9.29 days, and the average treatment time was 23.74±8.06 days. There was no influence of Blood leukocyte count, Neutrophil count, lymphocyte count, C-reactive protein (CRP), glutamic-pyruvic transaminase (ALT), glutamic oxalacetic transaminase (AST), creatinine, D-dimer on the prognosis of the patients, whether univariate or multivariate logistic regression analysis. By χ2 test of the drugs and prognosis, we found that oseltamivir may have an impact on the prognosis of patients (P<0.05), while other drugs have no significant impact on the prognosis of patients. Through the correlation analysis, we found that age, the admission temperature, leukocyte count, neutrophil count, CRP were positively correlated with the treatment time of the patients (both P<0.05). Leukocyte count and neutrophil count were positively correlated with the time of nucleic acid test turning negative (both P<0.05).Conclusions: Age, the admission temperature, leukocyte count, neutrophil count, CRP were positively correlated with the treatment time of the patients. Leukocyte count and neutrophil count were positively correlated with the time of nucleic acid test turning negative. Oseltamivir may have an impact on the prognosis of patients, but the detailed role needs further study.