Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), emerged at the end of 2019 and by mid-June 2020 the virus had spread to at ...least 215 countries, caused more than 8 000 000 confirmed infections and over 450 000 deaths, and overwhelmed healthcare systems worldwide. Like severe acute respiratory syndrome coronavirus (SARS-CoV), which emerged in 2002 and caused a similar disease, SARS-CoV-2 is a betacoronavirus. Both viruses use human angiotensin-converting enzyme 2 (hACE2) as a receptor to enter cells. However, the SARS-CoV-2 spike (S) glycoprotein has a novel insertion that generates a putative furin cleavage signal and this has been postulated to expand the host range. Two low-passage (P) strains of SARS-CoV-2 (Wash1 : P4 and Munich : P1) were cultured twice in Vero E6 cells and characterized virologically. Sanger and MinION sequencing demonstrated significant deletions in the furin cleavage signal of Wash1 : P6 and minor variants in the Munich : P3 strain. Cleavage of the S glycoprotein in SARS-CoV-2-infected Vero E6 cell lysates was inefficient even when an intact furin cleavage signal was present. Indirect immunofluorescence demonstrated that the S glycoprotein reached the cell surface. Since the S protein is a major antigenic target for the development of neutralizing antibodies, we investigated the development of neutralizing antibody titres in serial serum samples obtained from COVID-19 human patients. These were comparable regardless of the presence of an intact or deleted furin cleavage signal. These studies illustrate the need to characterize virus stocks meticulously prior to performing either
or
pathogenesis studies.
To examine the association between the extent of surgery and overall survival in a large contemporary cohort of patients with papillary thyroid cancer (PTC).
Guidelines recommend total thyroidectomy ...for PTC tumors >1 cm, based on older data demonstrating an overall survival advantage for total thyroidectomy over lobectomy.
Adult patients with PTC tumors 1.0-4.0 cm undergoing thyroidectomy in the National Cancer Database, 1998-2006, were included. Cox proportional hazards models were applied to measure the association between the extent of surgery and overall survival while adjusting for patient demographic and clinical factors, including comorbidities, extrathyroidal extension, multifocality, nodal and distant metastases, and radioactive iodine treatment.
Among 61,775 PTC patients, 54,926 underwent total thyroidectomy and 6849 lobectomy. Compared with lobectomy, patients undergoing total thyroidectomy had more nodal (7% vs 27%), extrathyroidal (5% vs 16%), and multifocal disease (29% vs 44%) (all Ps < 0.001). Median follow-up was 82 months (range, 60-179 months). After multivariable adjustment, overall survival was similar in patients undergoing total thyroidectomy versus lobectomy for tumors 1.0-4.0 cm hazard ratio (HR) = 0.96; 95% confidence interval (CI), 0.84-1.09); P = 0.54 and when stratified by tumor size: 1.0-2.0 cm HR = 1.05; 95% CI, 0.88-1.26; P = 0.61 and 2.1-4.0 cm HR = 0.89; 95% CI, 0.73-1.07; P = 0.21. Older age, male sex, black race, lower income, tumor size, and presence of nodal or distant metastases were independently associated with compromised survival (P < 0.0001).
Current guidelines suggest total thyroidectomy for PTC tumors >1 cm. However, we did not observe a survival advantage associated with total thyroidectomy compared with lobectomy. These findings call into question whether tumor size should be an absolute indication for total thyroidectomy.
Despite an increasing number of women in the field of surgery, bias regarding cognitive or technical ability may continue to affect the experience of female trainees differently than their male ...counterparts. This study examines the differences in the degree of operative autonomy given to female compared with male general surgery trainees.
A smartphone app was used to collect evaluations of operative autonomy measured using the 4-point Zwisch scale, which describes defined steps in the progression from novice ("show and tell") to autonomous surgeon ("supervision only"). Differences in autonomy between male and female residents were compared using hierarchical logistic regression analysis.
A total of 412 residents and 524 faculty from 14 general surgery training programs evaluated 8,900 cases over a 9-month period. Female residents received less autonomy from faculty than did male residents overall (P < .001). Resident level of training and case complexity were the strongest predictors of autonomy. Even after controlling for potential confounding factors, including level of training, intrinsic procedural difficulty, patient-related case complexity, faculty sex, and training program environment, female residents still received less operative autonomy than their male counterparts. The greatest discrepancy was in the fourth year of training.
There is a sex-based difference in the autonomy granted to general surgery trainees. This gender gap may affect female residents’ experience in training and possibly their preparation for practice. Strategies need to be developed to help faculty and residents work together to overcome this gender gap.
Globally, there is an urgency to develop effective, low-cost therapeutic interventions for coronavirus disease 2019 (COVID-19). We previously generated the stable and ultrapotent homotrimeric ...Pittsburgh inhalable Nanobody 21 (PiN-21). Using Syrian hamsters that model moderate to severe COVID-19 disease, we demonstrate the high efficacy of PiN-21 to prevent and treat SARS-CoV-2 infection. Intranasal delivery of PiN-21 at 0.6 mg/kg protects infected animals from weight loss and substantially reduces viral burdens in both lower and upper airways compared to control. Aerosol delivery of PiN-21 facilitates deposition throughout the respiratory tract and dose minimization to 0.2 mg/kg. Inhalation treatment quickly reverses animals' weight loss after infection, decreases lung viral titers by 6 logs leading to drastically mitigated lung pathology, and prevents viral pneumonia. Combined with the marked stability and low production cost, this innovative therapy may provide a convenient and cost-effective option to mitigate the ongoing pandemic.
The primary aim of this phase III randomized trial was to test whether the addition of vincristine, topotecan, and cyclophosphamide (VTC) to interval compressed chemotherapy improved survival ...outcomes for patients with previously untreated nonmetastatic Ewing sarcoma.
Patients were randomly assigned to receive standard five-drug interval compressed chemotherapy (regimen A) for 17 cycles or experimental therapy with five cycles of VTC within the 17 cycles (regimen B). Patients were stratified by age at diagnosis (< 18 years and ≥18 years) and tumor site (pelvic bone, nonpelvic bone, and extraosseous). Tumor volume at diagnosis was categorized as < 200 mL or ≥ 200 mL. Local control occurred following six cycles. Histologic response was categorized as no viable or any viable tumor. Event-free survival (EFS) and overall survival (OS) were compared between randomized groups with stratified log-rank tests.
Of 642 enrolled patients, 309 eligible patients received standard and 320 received experimental therapy. The 5-year EFS and OS were 78% and 87%, respectively. There was no difference in survival outcomes between randomized groups (5-year EFS regimen A
regimen B, 78%
79%;
= .192; 5-year OS 86%
88%;
= .159). Age and primary site did not affect the risk of an EFS event. However, age ≥ 18 years was associated with an increased risk of death at 5 years (hazard ratio 1.84; 95% CI, 1.15 to 2.96;
= .009). The 5-year EFS rates for patients with pelvic, nonpelvic bone, and extraosseous primary tumors were 75%, 78%, and 85%, respectively. Tumor volume ≥ 200 mL was significantly associated with lower EFS.
While VTC added to five-drug interval compressed chemotherapy did not improve survival, these outcomes represent the best survival estimates to date for patients with previously untreated nonmetastatic Ewing sarcoma.
Development of antiviral drugs that have broad-spectrum activity against a number of viral infections would be of significant benefit. Due to the evolution of resistance to currently licensed ...antiviral drugs, development of novel anti-influenza drugs is in progress, including Favipiravir (T-705), which is currently in human clinical trials. T-705 displays broad-spectrum in vitro activity against a number of viruses, including Rift Valley Fever virus (RVFV). RVF is an important neglected tropical disease that causes human, agricultural, and economic losses in endemic regions. RVF has the capacity to emerge in new locations and also presents a potential bioterrorism threat. In the current study, the in vivo efficacy of T-705 was evaluated in Wistar-Furth rats infected with the virulent ZH501 strain of RVFV by the aerosol route.
Wistar-Furth rats are highly susceptible to a rapidly lethal disease after parenteral or inhalational exposure to the pathogenic ZH501 strain of RVFV. In the current study, two experiments were performed: a dose-determination study and a delayed-treatment study. In both experiments, all untreated control rats succumbed to disease. Out of 72 total rats infected with RVFV and treated with T-705, only 6 succumbed to disease. The remaining 66 rats (92%) survived lethal infection with no significant weight loss or fever. The 6 treated rats that succumbed survived significantly longer before succumbing to encephalitic disease.
Currently, there are no licensed antiviral drugs for treating RVF. Here, T-705 showed remarkable efficacy in a highly lethal rat model of Rift Valley Fever, even when given up to 48 hours post-infection. This is the first study to show protection of rats infected with the pathogenic ZH501 strain of RVFV. Our data suggest that T-705 has potential to be a broad-spectrum antiviral drug.
Rift Valley fever virus (RVFV) causes severe disease in livestock concurrent with zoonotic transmission to humans. A subset of people infected with RVFV develop encephalitis, and significant gaps ...remain in our knowledge of how RVFV causes pathology in the brain. We previously found that, in Lewis rats, subcutaneous inoculation with RVFV resulted in subclinical disease while inhalation of RVFV in a small particle aerosol caused fatal encephalitis. Here, we compared the disease course of RVFV in Lewis rats after each different route of inoculation in order to understand more about pathogenic mechanisms of fatal RVFV encephalitis. In aerosol-infected rats with lethal encephalitis, neutrophils and macrophages were the major cell types infiltrating the CNS, and this was concomitant with microglia activation and extensive cytokine inflammation. Despite this, prevention of neutrophil infiltration into the brain did not ameliorate disease. Unexpectedly, in subcutaneously-inoculated rats with subclinical disease, detectable viral RNA was found in the brain along with T-cell infiltration. This study sheds new light on the pathogenic mechanisms of RVFV encephalitis.
Examining the persistence of highly pathogenic avian influenza A(H5N1) from cattle and human influenza A(H1N1)pdm09 pandemic viruses in unpasteurized milk revealed that both remain infectious on ...milking equipment materials for several hours. Those findings highlight the risk for H5N1 virus transmission to humans from contaminated surfaces during the milking process.Examining the persistence of highly pathogenic avian influenza A(H5N1) from cattle and human influenza A(H1N1)pdm09 pandemic viruses in unpasteurized milk revealed that both remain infectious on milking equipment materials for several hours. Those findings highlight the risk for H5N1 virus transmission to humans from contaminated surfaces during the milking process.
In his dissent in Plessy v. Ferguson, Justice John Marshall Harlan wrote, “Our constitution is color-blind, and neither knows nor tolerates classes among citizens.” Racial conservatives have argued ...that Harlan's dissent should invalidate policies that partially redress the historical injuries inflicted on African Americans. This article contends that the concept of colorblindness misstates Harlan's central claim. His dissent insisted black Americans are entitled to the full fruits of citizenship. This rearticulation reveals that race-conscious policies, particularly within public education, fulfill, rather than undermine, Harlan's primary objective of defending black citizenship. The article shows that racial conservatives' colorblind ideology emerged as a strategic response to their legal defeats over segregated schools and to attack affirmative action. The Supreme Court's later use of colorblind principles is contrasted with empirical evidence of the efficacy of color-conscious pedagogies within schools. The recent Gary B. v. Whitmer case highlights the linkages between full citizenship and race-conscious pedagogies.
Live attenuated vaccines (LAVs), if sufficiently safe, provide the most potent and durable anti-pathogen responses in vaccinees with single immunizations commonly yielding lifelong immunity. ...Historically, viral LAVs were derived by blind passage of virulent strains in cultured cells resulting in adaptation to culture and a loss of fitness and disease-causing potential in vivo. Mutations associated with these phenomena have been identified but rarely have specific attenuation mechanisms been ascribed, thereby limiting understanding of the attenuating characteristics of the LAV strain and applicability of the attenuation mechanism to other vaccines. Furthermore, the attenuated phenotype is often associated with single nucleotide changes in the viral genome, which can easily revert to the virulent sequence during replication in animals. Here, we have used a rational approach to attenuation of eastern equine encephalitis virus (EEEV), a mosquito-transmitted alphavirus that is among the most acutely human-virulent viruses endemic to North America and has potential for use as an aerosolized bioweapon. Currently, there is no licensed antiviral therapy or vaccine for this virus. Four virulence loci in the EEEV genome were identified and were mutated individually and in combination to abrogate virulence and to resist reversion. The resultant viruses were tested for virulence in mice to examine the degree of attenuation and efficacy was tested by subcutaneous or aerosol challenge with wild type EEEV. Importantly, all viruses containing three or more mutations were avirulent after intracerebral infection of mice, indicating a very high degree of attenuation. All vaccines protected from subcutaneous EEEV challenge while a single vaccine with three mutations provided reproducible, near-complete protection against aerosol challenge. These results suggest that informed mutation of virulence determinants is a productive strategy for production of LAVs even with highly virulent viruses such as EEEV. Furthermore, these results can be directly applied to mutation of analogous virulence loci to create LAVs from other viruses.
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