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Hemagglutinins (HA's) from duck, swine, and human influenza viruses have previously been shown to prefer avian and human glycan receptor analogues with distinct topological profiles, pentasaccharides LSTa (alpha-2,3 linkage) and LSTc (alpha-2,6 linkage), in comparative molecular dynamics studies. On the basis of detailed analyses of the dynamic motions of the receptor binding domains (RBDs) and interaction energy profiles with individual glycan residues, we have identified approximately 30 residue positions in the RBD that present distinct profiles with the receptor analogues. Glycan binding constrained the conformational space sampling by the HA. Electrostatic steering appeared to play a key role in glycan binding specificity. The complex dynamic behaviors of the major SSE and trimeric interfaces with or without bound glycans suggested that networks of interactions might account for species specificity in these low affinity and high avidity (multivalent) interactions between different HA and glycans. Contact frequency, energetic decomposition, and H-bond analyses revealed species-specific differences in HA-glycan interaction profiles, not readily discernible from crystal structures alone. Interaction energy profiles indicated that mutation events at the set of residues such as 145, 156, 158, and 222 would favor human or avian receptor analogues, often through interactions with distal asialo-residues. These results correlate well with existing experimental evidence, and suggest new opportunities for simulation-based vaccine and drug development.

A simple theory is developed to relate the optical absorption spectrum of a two-dimensional dye aggregate, either dispersed in a transparent matrix or deposited on a transparent substrate, to the spectra of a crystal that consists of a stack of such aggregate layers. Spectral data can then provide evidence on whether the structure of such an aggregate is similar to that of a layer in the crystal. A thiapyrylium dye aggregate dispersed in a polymer film is treated as an example. [ABSTRACT FROM AUTHOR]

Older Americans who live alone are an often forgotten group, although their numbers are increasing, and they are particularly vulnerable when faced with a chronic illness such as Alzheimer's disease (AD). An estimated one fifth of individuals with some form of dementia live alone; the challenge facing most communities is how to first identify, and then respond to, this population in a way that preserves their independence and dignity and at the same time helps keep their environment safe. A review of one community's attempt to respond to this challenge is described. Realizing that addressing the needs of live alones transcended the scope of any single agency, the Alzheimer's Association, Big Sioux Chapter mobilized a diverse group of service providers and other community stakeholders to develop a proactive plan to identify and assist local live alones. [ABSTRACT FROM AUTHOR]

Background: Mink farms are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks and carry an associated risk of novel SARS-CoV-2 variant emergence and non-human reservoir creation. In Denmark, control measures were insufficient to prevent onward transmission of a mink-associated variant, contributing to the nation-wide culling of farmed mink. To date, British Columbia (BC) is the only Canadian province to report mink farm SARS-CoV-2 outbreaks. The objective of this study is to describe BC's One Health response to SARS-CoV-2-associated risk from mink farming, its outcomes, and insights from implementation., Methods: The detection of two mink farm outbreaks in December 2020 catalyzed BC's risk mitigation response for both infected and uninfected farms, including the following: farm inspections and quarantines; Public Health Orders mandating mink mortality surveillance, enhanced personal protective equipment, biosafety measures and worker coronavirus disease 2019 vaccination, at-a-minimum weekly worker viral testing, and wildlife surveillance., Results: A One Health approach enabled a timely, evidence-informed and coordinated response as the situation evolved, including the use of various legislative powers, consistent messaging and combined human and mink phylogenetic analysis. Ongoing mink and worker surveillance detected asymptomatic/subclinical infections and facilitated rapid isolation/quarantine to minimize onward transmission. Voluntary testing and mandatory vaccination for workers were acceptable to industry; enhanced personal protective equipment requirements were challenging. Regular farm inspections helped to assess and improve compliance., Conclusion: British Columbia's One Health response reduced the risk of additional outbreaks, viral evolution and reservoir development; however, a third outbreak was detected in May 2021 despite implemented measures, and long-term sustainability of interventions proved challenging for both industry and governmental agencies involved., Competing Interests: Competing interests: None., (Public Health Agency of Canada, 2022.)

Objectives: Define clinical spectrum and long-term outcomes of gut malrotation. With new insights, an innovative procedure was introduced and predictive models were established., Methods: Over 30-years, 500 patients were managed at 2 institutions. Of these, 274 (55%) were children at time of diagnosis. At referral, 204 (41%) patients suffered midgut-loss and the remaining 296 (59%) had intact gut with a wide range of digestive symptoms. With midgut-loss, 189 (93%) patients underwent surgery with gut transplantation in 174 (92%) including 16 of 31 (16%) who had autologous gut reconstruction. Ladd's procedure was documented in 192 (38%) patients with recurrent or de novo volvulus in 41 (21%). For 80 patients with disabling gastrointestinal symptoms, gut malrotation correction (GMC) surgery "Kareem's procedure" was offered with completion of the 270° embryonic counterclockwise-rotation, reversal of vascular-inversion, and fixation of mesenteric-attachments. Concomitant colonic dysmotility was observed in 25 (31%) patients., Results: The cumulative risk of midgut-loss increased with volvulus, prematurity, gastroschisis, and intestinal atresia whereas reduced with Ladd's and increasing age. Transplant cumulative survival was 63% at 10-years and 54% at 20-years with best outcome among infants and liver-containing allografts. Autologous gut reconstruction achieved 78% and GMC had 100% 10-year survival. Ladd's was associated with 21% recurrent/de novo volvulus and worsening (P > 0.05) of the preoperative National Institute of Health patient-reported outcomes measurement information system gastrointestinal symptom scales. GMC significantly (P ≤ 0.001) improved all of the symptomatology domains with no technical complications or development of volvulus. GMC improved quality of life with restored nutritional autonomy (P < 0.0001) and daily activities (P < 0.0001)., Conclusions: Gut malrotation is a clinicopathologic syndrome affecting all ages. The introduced herein definitive correction procedure is safe, effective, and easy to perform. Accordingly, the current standard of care practice should be redefined in this orphan population., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Objective(s): To define the evolving role of integrative surgical management including transplantation for patients gut failure (GF)., Methods: A total of 500 patients with total parenteral nutrition-dependent catastrophic and chronic GF were referred for surgical intervention particularly transplantation and comprised the study population. With a mean age of 45 ± 17 years, 477 (95%) were adults and 23 (5%) were children. Management strategy was guided by clinical status, splanchnic organ functions, anatomy of residual gut, and cause of GF. Surgery was performed in 462 (92%) patients and 38 (8%) continued medical treatment. Definitive autologous gut reconstruction (AGR) was achievable in 378 (82%), primary transplant in 42 (9%), and AGR followed by transplant in 42 (9%). The 84 transplant recipients received 94 allografts; 67 (71%) liver-free and 27 (29%) liver-contained. The 420 AGR patients received a total of 790 reconstructive and remodeling procedures including primary reconstruction, interposition alimentary-conduits, intestinal/colonic lengthening, and reductive/decompressive surgery. Glucagon-like peptide-2 was used in 17 patients., Results: Overall patient survival was 86% at 1-year and 68% at 5-years with restored nutritional autonomy (RNA) in 63% and 78%, respectively. Surgery achieved a 5-year survival of 70% with 82% RNA. AGR achieved better long-term survival and transplantation better (P = 0.03) re-established nutritional autonomy. Both AGR and transplant were cost effective and quality of life better improved after AGR. A model to predict RNA after AGR was developed computing anatomy of reconstructed gut, total parenteral nutrition requirements, cause of GF, and serum bilirubin., Conclusions: Surgical integration is an effective management strategy for GF. Further progress is foreseen with the herein-described novel techniques and established RNA predictive model.

Background: Spatial clusters of syphilis have been observed within several jurisdictions globally; however, the degree to which they are predicted by the spatial distributions of gay, bisexual, and other men who have sex with men (GBM) and testing remains unknown. We sought to describe the spatial-temporal epidemiology of infectious syphilis and identify associations between neighborhood-level factors and rates of syphilis, in British Columbia, Canada., Methods: We used ArcGIS to map infectious syphilis cases among men (2005 to 2016), SaTScan to detect areas with significantly elevated rates of syphilis, and spatial regression to identify associations between neighborhood-level factors and rates of syphilis., Results: Five clusters were identified: a core in downtown Vancouver (incidence rate ratio [IRR], 18.0; 2007-2016), 2 clusters adjacent to the core (IRR, 3.3; 2012-2016; and IRR, 2.2; 2013-2016), 1 cluster east of Vancouver (IRR, 2.1; 2013-2016), and 1 cluster in Victoria (IRR, 4.3; 2015-2016). Epidemic curves were synchronized across cluster and noncluster regions. Neighborhood-level GBM population estimates and testing rates were both associated with syphilis rates; however, the spatial distribution of syphilis was not fully explained by either of these factors., Conclusions: We identified two novel ecologic correlates of the spatial distribution of infectious syphilis-density of GBM and rates of syphilis testing-and found that these factors partially, though not entirely, explained the spatial distribution of clusters. Residual spatial autocorrelation suggests that greater syphilis testing coverage may be needed and low-barrier GBM-affirming testing should be expanded to regions outside the core.

Background: Mucormycosis is an invasive fungal infection with a high fatality rate. We investigated an outbreak of mucormycosis in a pediatric hospital to determine routes of pathogen transmission from the environment and prevent additional infections., Methods: A case was defined as a hospital-onset illness consistent with mucormycosis, confirmed by culture or histopathology. Case-patient medical records were reviewed for clinical course and exposure to items and locations within the hospital. Environmental samples were collected from air and surfaces. Fungal isolates collected from case-patients and the environmental samples were identified using DNA sequencing., Results: Five case-patients had hospital-associated cutaneous mucormycosis over an 11-month period; all subsequently died. Three case-patients had conditions known to be associated with susceptibility to mucormycosis, while 2 had cardiac conditions with persistent acidosis. The cases occurred on several different wards throughout the hospital, and hospital linens were the only exposure identified as common to the case-patients. Rhizopus species were recovered from 26 (42%) of 62 environmental samples from clean linens and associated areas and from 1 (4%) of 25 samples from nonlinen-related items. Case-patients were infected with Rhizopus delemar, which was also isolated from cultures of clean linens and clean linen delivery bins from the off-site laundry facility., Conclusions: Hospital linens were identified as a vehicle that carried R. delemar into contact with susceptible patients. Fungal species identification using DNA-based methods is useful for corroborating epidemiologic links in hospital outbreak investigations. Hospital linens should be laundered, packaged, shipped and stored in a manner that minimizes exposure to environmental contaminants.

Tracheotomy is one of the most common surgical procedures performed in the ICU setting. Traditionally tracheotomy has been performed by otolaryngologists as well as general surgeons. While percutaneous tracheotomy (PT) has been available for some time, it has only recently gained widespread acceptance with the advent of convenient and safe kits. Over the past decade, there has been increased utilization of this technique. However, there is a relative reluctance of certain surgical specialties to perform and train residents in PT; a previous study identified that only 29% of otolaryngology head and neck surgery (OTO-HNS) departments in the USA perform PT. In this study we aim to investigate the trends of PT usage in general surgery training programs and compare them to those previously described in otolaryngology programs. The study design is multi-institution physician survey and the study method was a survey of 250 general surgery program directors. This survey was identical to a published survey of OTO-HNS and a head-to-head comparison of results was performed. The response rate was 53% (133 programs). 89% of general surgery programs performed open tracheotomy on a regular basis. 75% performed percutaneous tracheotomy on a regular basis. 79% use the Ciaglia Blue Rhino method. Simultaneous video bronchoscopy was used by 67%. 83% of general surgery residency programs train their residents in PT. 61% felt that PT was either safer than or equal to open tracheotomy. PT is performed in a majority of general surgery residency programs and taught to their trainees. This is in contrast to otolaryngology residency programs, which have been shown to prefer open tracheotomies in both practice and teaching. This trend may severely impact the skills of the next generation of otolaryngologists.

A patient with a cervical cord transection isolating his hypothalamic thermoregulatory centers from peripheral effectors suffered a fatal hyperthermic episode after receiving haloperidol. This suggests that neuroleptic malignant syndrome is caused by a peripheral, not central, effect of haloperidol.