Implementation of a pooled surveillance testing program for asymptomatic SARS-CoV-2 infections in K-12 schools and universities.

BACKGROUND: The negative impact of continued school closures during the height of the COVID-19 pandemic warrants the establishment of cost-effective strategies for surveillance and screening to safely reopen and monitor for potential in-school transmission. Here, we present a novel approach to increase the availability of repetitive and routine COVID-19 testing that may ultimately reduce the overall viral burden in the community. METHODS: We implemented a testing program using the SalivaClear࣪ pooled surveillance method that included students, faculty and staff from K-12 schools (student age range 5-18 years) and universities (student age range >18 years) across the country (Mirimus Clinical Labs, Brooklyn, NY). The data analysis was performed using descriptive statistics, kappa agreement, and outlier detection analysis. FINDINGS: From August 27, 2020 until January 13, 2021, 253,406 saliva specimens were self-collected from students, faculty and staff from 93 K-12 schools and 18 universities. Pool sizes of up to 24 samples were tested over a 20-week period. Pooled testing did not significantly alter the sensitivity of the molecular assay in terms of both qualitative (100% detection rate on both pooled and individual samples) and quantitative (comparable cycle threshold (Ct) values between pooled and individual samples) measures. The detection of SARS-CoV-2 in saliva was comparable to the nasopharyngeal swab. Pooling samples substantially reduced the costs associated with PCR testing and allowed schools to rapidly assess transmission and adjust prevention protocols as necessary. In one instance, in-school transmission of the virus was determined within the main office and led to review and revision of heating, ventilating and air-conditioning systems. INTERPRETATION: By establishing low-cost, weekly testing of students and faculty, pooled saliva analysis for the presence of SARS-CoV-2 enabled schools to determine whether transmission had occurred, make data-driven decisions, and adjust safety protocols. We provide strong evidence that pooled testing may be a fundamental component to the reopening of schools by minimizing the risk of in-school transmission among students and faculty. FUNDING: Skoll Foundation generously provided funding to Mobilizing Foundation and Mirimus for these studies.

Simple bone cysts of the calcaneus: a report of five cases and a review of the literature.

BACKGROUND: Simple bone cysts of the calcaneus are relatively uncommon. There is no clear consensus on either their etiology or management. Pathological fractures of such cysts are exceptionally rare. MATERIALS AND METHODS: Five simple bone cysts of the calcaneus were present in three males and two females with an average age of 44 years. One patient presented with pain, three cysts were incidental findings on ankle radiographs, and one patient presented with a fracture after a significant fall. RESULTS: All five were managed nonoperatively and had satisfactory outcomes. CONCLUSIONS: A review the literature on the etiology and management of simple bone cysts of the calcaneus and the outcomes of these patients indicate that complications of these cysts are rare and nonoperative management is appropriate.

Cholelithoptysis: an unusual delayed complication of laparoscopic cholecystectomy.

We report the case of a 54-year old woman who presented with a persistent right lower lobe pneumonia followed by cholelithoptysis, 11 months after a laparoscopic cholecystectomy. It is postulated that this was a result of the formation of a subphrenic abscess secondary to intraoperative spillage of gallstones. It is concluded that spillage of gallstones at laparoscopic cholecystectomy is not as benign as previously thought and that efforts to prevent spillage should include scrupulous operative technique, especially in the presence of gallbladder inflammation, and especial care when removing the gallbladder from the abdominal cavity.

Analysis of the Vibronic Structure in the Emission and Absorption Spectra of (&mgr;-1,1-Dicyanoethylene-2,2-dithiolato-S,S')bis(triphenylphosphine)digold(I) and Assignment of the Emissive State.

Both the 77 K single crystal absorption and 20 K emission spectrum of (&mgr;-1,1-dicyanoethylene-2,2-dithiolato-S,S')bis(triphenylphosphine)digold(I), (AuPPh(3))(2)[i-MNT], show resolved vibronic structure. Progressions in the 1410 cm(-)(1) C=C stretching mode of the dithiolate ligand, and in the 480 cm(-)(1) mode, which involves gold-dithiolate stretching, are observed in the emission spectrum. The resonance Raman spectra of the title compound and related compounds were used to identify the modes that give rise to the vibronic structure observed in the emission spectrum. The emission spectrum is fit using the time dependent theory of electronic spectroscopy. The theoretical fit to the spectrum requires distortions in vibrations involving both the metal-sulfur and dithiolate centered modes. These distortions show that the transition is a charge transfer involving the gold and the dithiolate ligand. The emission spectrum of an analogous complex, (AuAsPh(3))(2)[i-MNT], is red shifted relative to the title complex. This red shift allows the direction of the charge transfer emission in the title complex to be assigned as a dithiolate to gold, ligand to metal charge transfer.