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1.
Clin Exp Dermatol ; 49(8): 801-809, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-38240024

ABSTRACT

BACKGROUND: Secukinumab, an anti-interleukin (IL)-17A monoclonal antibody, induces histological and molecular resolution of psoriatic plaques by 12 weeks. However, the long-term effects of secukinumab on the molecular resolution of psoriatic inflammation remain unknown. OBJECTIVES: To investigate the molecular resolution of psoriasis following 52 weeks of secukinumab treatment. METHODS: This was a two-part phase II randomized double-blinded placebo-controlled 52-week study of patients with moderate-to-severe psoriasis receiving secukinumab 300 mg (NCT01537432). Psoriatic lesional and nonlesional skin biopsies were obtained at baseline and at weeks 12 and 52, and the composition of the residual disease genomic profile (RDGP; i.e. 'molecular scar') of biopsies from secukinumab responders analysed. RESULTS: After 52 weeks of treatment, 14 of 24 enrolled patients were considered to be clinical responders [≥ 75% improvement in Psoriasis Area and Severity Index (PASI 75)], 4 of 24 were considered to be nonresponders (< PASI 75) and 6 of 24 patients were lost to follow-up; both the histological and transcriptomic profiles of PASI 75 responders improved from week 12 to week 52. RDGP transcripts of histological responders only partially overlapped between weeks 12 and 52, despite a similar number of transcripts in each RDGP; specifically, four novel transcript subsets showed distinct expression dynamics between weeks 12 and 52 ('slow-resolving', 'recurring', 'persistent' and 'resolved'), with anti-inflammatory and immunomodulatory genes (e.g. SOCS1, CD207 and IL37) notably restored at week 52. Shorter disease duration prior to secukinumab treatment coincided with greater transcript improvements at weeks 12 and 52. CONCLUSIONS: Secukinumab improves the histological and molecular phenotype of psoriatic lesional skin up to 52 weeks of treatment; these results suggest possible mechanisms that drive long-term control of psoriasis.


Subject(s)
Antibodies, Monoclonal, Humanized , Interleukin-17 , Psoriasis , Transcriptome , Humans , Psoriasis/drug therapy , Psoriasis/genetics , Psoriasis/pathology , Antibodies, Monoclonal, Humanized/therapeutic use , Interleukin-17/metabolism , Interleukin-17/antagonists & inhibitors , Double-Blind Method , Male , Female , Adult , Middle Aged , Antibodies, Monoclonal/therapeutic use , Severity of Illness Index , Biomarkers/metabolism , Skin/pathology , Skin/metabolism , Treatment Outcome
2.
Biochemistry ; 62(5): 1032-1043, 2023 03 07.
Article in English | MEDLINE | ID: mdl-36808948

ABSTRACT

Accelerated spontaneous deamidation of asparagine 373 and subsequent conversion into an isoaspartate has been shown to attenuate the binding of histo blood group antigens (HBGAs) to the protruding domain (P-domain) of the capsid protein of a prevalent norovirus strain (GII.4). Here, we link an unusual backbone conformation of asparagine 373 to its fast site-specific deamidation. NMR spectroscopy and ion exchange chromatography have been used to monitor the deamidation reaction of P-domains of two closely related GII.4 norovirus strains, specific point mutants, and control peptides. MD simulations over several microseconds have been instrumental to rationalize the experimental findings. While conventional descriptors such as available surface area, root-mean-square fluctuations, or nucleophilic attack distance fail as explanations, the population of a rare syn-backbone conformation distinguishes asparagine 373 from all other asparagine residues. We suggest that stabilization of this unusual conformation enhances the nucleophilicity of the backbone nitrogen of aspartate 374, in turn accelerating the deamidation of asparagine 373. This finding should be relevant to the development of reliable prediction algorithms for sites of rapid asparagine deamidation in proteins.


Subject(s)
Capsid Proteins , Norovirus , Capsid Proteins/chemistry , Binding Sites , Asparagine/metabolism , Norovirus/genetics , Protein Domains , Protein Binding
3.
J Clin Microbiol ; 61(8): e0190522, 2023 08 23.
Article in English | MEDLINE | ID: mdl-37439667

ABSTRACT

Mycoplasma bovis is a fastidious pathogen of cattle causing massive economic losses in the calf and dairy industries worldwide. Since there is no approved standard method for antimicrobial susceptibility testing (AST) of M. bovis, the Clinical and Laboratory Standards Institute has requested the development of a suitable method. Therefore, this study aimed at developing a method for harmonized broth microdilution AST of M. bovis. For this, 131 M. bovis field isolates and M. bovis strain DSM 22781T were collected and macrorestriction analysis was performed to select 15 epidemiologically unrelated M. bovis strains for method validation steps. To select a suitable broth for AST of M. bovis, growth determinations were performed using five media and growth curves were compiled. Then, susceptibility testing was performed considering the exact (precondition of five identical MICs) and essential (MIC mode, accepting a deviation of ±1 dilution step) MIC agreements to evaluate the reproducibility of MIC values using a panel of 16 antimicrobial agents. Subsequently, the remaining field isolates were tested and the suitability of quality control (QC) strains was assessed. Growth experiments showed that SP4 broth was the only one of the five media that yielded sufficient growth of M. bovis. Therefore, it was selected as the test medium for AST and homogeneous MIC values were obtained (exact and essential agreements of 36 to 100% and 92 to 100%, respectively). For all other isolates tested, easy-to-read MIC endpoints were determined with this medium. High overall MIC50 and/or MIC90 values were observed for aminoglycosides and macrolides, and some isolates showed elevated MICs of fluoroquinolones, gentamicin, and/or tiamulin. Since the MICs of four commonly used QC strains were partially not within their ranges, a 20-fold MIC testing of M. bovis DSM 22781T was performed and met the criteria for a new QC strain. For harmonized AST of M. bovis, SP4 broth seems to be suitable with an incubation time of 72 ± 2 h and further validation of M. bovis DSM 22781T as a future QC strain is recommended.


Subject(s)
Anti-Infective Agents , Mycoplasma bovis , Animals , Cattle , Reproducibility of Results , Anti-Bacterial Agents/pharmacology , Fluoroquinolones , Culture Media , Microbial Sensitivity Tests
4.
J Occup Environ Hyg ; 20(2): 120-128, 2023 02.
Article in English | MEDLINE | ID: mdl-36445186

ABSTRACT

Agricultural workers are more prone to noise-induced hearing loss than are many other workers. Hearing protection device use among agricultural workers is low, but training can increase hearing protection device use. This work proposes a system designed to automatically inform agricultural workers when they were exposed to noises that exceed the National Institute for Occupational Safety and Health (NIOSH) recommended exposure level. The smartphone-based system worn on the arm uses a noise dosimeter to measure noise exposures throughout the day to within ±2 A-weighted decibels of a Class 2 sound level meter. The device collects location and audio data, which are transferred to a server and presented to the worker on a locally hosted website. The website details noise exposure and helps the worker identify where exposure occurred and what specific tasks exceed NIOSH's recommended exposure limit, putting them at higher risk of noise-induced hearing loss. With this understanding, the worker is expected to adopt behavior changes and better hearing protection use at critical places and times. This pilot study evaluates the accuracy of the noise dosimeter and GPS relative to gold-standard instruments. The system was tested on a farm with outputs compared with gold-standard instruments. A-weighted, 1-sec averaged sound pressure levels and position data were collected while users were performing a variety of tasks indoors and outdoors. The smartphone's external noise dosimeter read within ±2 A-weighted decibels of the Class 2 reference dosimeter 59% of the time. The positioning devices had an average error of sub-4 m. While not perfectly matching gold-standard instruments, the device is capable of identifying and collecting information relative to loud noise events that promote noise-induced hearing loss.


Subject(s)
Hearing Loss, Noise-Induced , Noise, Occupational , Occupational Exposure , Occupational Health , Humans , Hearing Loss, Noise-Induced/etiology , Hearing Loss, Noise-Induced/prevention & control , Noise, Occupational/adverse effects , Noise, Occupational/prevention & control , Pilot Projects
5.
J Am Chem Soc ; 144(29): 13060-13065, 2022 07 27.
Article in English | MEDLINE | ID: mdl-35830336

ABSTRACT

We have used chemical shift perturbation (CSP) and saturation transfer difference (STD) NMR experiments to identify and characterize the binding of selected ligands to the receptor-binding domain (RBD) of the spike glycoprotein (S-protein) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We also subjected full-length S-protein to STD NMR experiments, allowing correlations with RBD-based results. CSPs reveal the binding sites for heparin and fondaparinux, and affinities were measured using CSP titrations. We then show that α-2,3-sialyllactose binds to the S-protein but not to the RBD. Finally, combined CSP and STD NMR experiments show that lifitegrast, a compound used for the treatment of dry eye, binds to the linoleic acid (LA) binding pocket with a dissociation constant in the µM range. This is an interesting finding, as lifitegrast lends itself well as a blueprint for medicinal chemistry, eventually furnishing novel entry inhibitors targeting the highly conserved LA binding site.


Subject(s)
COVID-19 Drug Treatment , Spike Glycoprotein, Coronavirus , Angiotensin-Converting Enzyme 2 , Binding Sites , Humans , Ligands , Magnetic Resonance Spectroscopy , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/metabolism , Protein Binding , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry
6.
Biochem Soc Trans ; 50(1): 347-359, 2022 02 28.
Article in English | MEDLINE | ID: mdl-34940787

ABSTRACT

Infection with human noroviruses requires attachment to histo blood group antigens (HBGAs) via the major capsid protein VP1 as a primary step. Several crystal structures of VP1 protruding domain dimers, so called P-dimers, complexed with different HBGAs have been solved to atomic resolution. Corresponding binding affinities have been determined for HBGAs and other glycans exploiting different biophysical techniques, with mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy being most widely used. However, reported binding affinities are inconsistent. At the extreme, for the same system MS detects binding whereas NMR spectroscopy does not, suggesting a fundamental source of error. In this short essay, we will explain the reason for the observed differences and compile reliable and reproducible binding affinities. We will then highlight how a combination of MS techniques and NMR experiments affords unique insights into the process of HBGA binding by norovirus capsid proteins.


Subject(s)
Blood Group Antigens , Norovirus , Binding Sites , Blood Group Antigens/chemistry , Blood Group Antigens/metabolism , Capsid Proteins/chemistry , Capsid Proteins/metabolism , Humans , Norovirus/chemistry , Norovirus/metabolism , Polysaccharides/metabolism , Protein Binding
7.
Clin Exp Allergy ; 52(11): 1247-1263, 2022 11.
Article in English | MEDLINE | ID: mdl-35947495

ABSTRACT

This review presents an overview of the available literature regarding intranasal corticosteroids (INCs) for the treatment of allergic rhinitis (AR). Various treatment options exist for AR including INCs, antihistamines and leucotriene antagonists. INCs are considered to be the most effective therapy for moderate-to-severe AR, as they are effective against nasal and ocular symptoms and improve quality of life. Their safety has been widely observed. INCs are effective and safe for short-term use. Local adverse events are observed but generally well-tolerated. The occurrence of (serious) systemic adverse events is unlikely but cannot be ruled out. There is a lack of long-term safety data. INC may cause serious eye complications. The risk of INCs on the hypothalamic-pituitary-adrenal axis, on bone mineral density reduction or osteoporosis and on growth in children, should be considered during treatment. Pharmacological characteristics of INCs (e.g. the mode of action and pharmacokinetics) are well known and described. We sought to gain insight into whether specific properties affect the efficacy and safety of INCs, including nasal particle deposition, which the administration technique affects. However, advances are lacking regarding the improved understanding of the effect of particle deposition on efficacy and safety and the effect of the administration technique. This review emphasizes the gaps in knowledge regarding this subject. Advances in research and health care are necessary to improve care for patients with AR.


Subject(s)
Quality of Life , Rhinitis, Allergic , Child , Humans , Hypothalamo-Hypophyseal System , Pituitary-Adrenal System , Rhinitis, Allergic/drug therapy , Adrenal Cortex Hormones , Administration, Intranasal , Histamine Antagonists/therapeutic use
8.
Exp Dermatol ; 31(10): 1522-1532, 2022 10.
Article in English | MEDLINE | ID: mdl-35638561

ABSTRACT

Hidradenitis Suppurativa (HS) is a chronic, recurrent, inflammatory, follicular skin disease whose pathology is complex and not fully understood. The objective of this study was to elucidate the role of IL-17A in moderate-to-severe HS. Transcriptomic and histological analyses were conducted on ex vivo HS (n = 19; lesional and non-lesional) and healthy control (n = 8) skin biopsies. Further, a Phase II exploratory, randomized, double-blind, placebo-controlled study was carried out in moderate-to-severe HS patients. Patients were treated with either CJM112 300 mg (n = 33), a fully human anti-IL-17A IgG1/κ monoclonal antibody, or placebo (n = 33). The main outcome of the translational analyses was to identify IL-17A-producing cells and indications of IL-17A activity in HS lesional skin. The primary objective of the clinical study was to determine the efficacy of CJM112 in moderate-to-severe HS patients by HS-Physician Global Assessment (HS-PGA) responder rate at Week 16. Transcriptomic and histopathologic analyses revealed the presence of heterogeneous cell types in HS lesional skin; IL-17A gene signatures were increased in HS lesional vs non-lesional or healthy skin. High expression of IL-17A was localized to T cells, neutrophils, and mast cells, confirming the transcriptional data. Clinically, the proportion of Week 16 HS-PGA responders was significantly higher (p = 0.03) in the CJM112 group vs placebo (32.3% vs 12.5%). This study elucidated the role of the IL-17A pathway in HS pathogenesis and clinically validated the IL-17A pathway in moderate-to-severe HS patients in a proof-of-concept study using the anti-IL-17A-specific antibody CJM112.


Subject(s)
Dermatitis , Hidradenitis Suppurativa , Humans , Antibodies, Monoclonal/therapeutic use , Dermatitis/metabolism , Hidradenitis Suppurativa/genetics , Immunoglobulin G/metabolism , Skin/metabolism
9.
Chemistry ; 28(71): e202202614, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36161798

ABSTRACT

We have used NMR experiments to explore the binding of selected glycans and glycomimetics to the SARS CoV-2 spike glycoprotein (S-protein) and to its receptor binding domain (RBD). STD NMR experiments confirm the binding of sialoglycans to the S-protein of the prototypic Wuhan strain virus and yield dissociation constants in the millimolar range. The absence of STD effects for sialoglycans in the presence of the Omicron/BA.1 S-protein reflects a loss of binding as a result of S-protein evolution. Likewise, no STD effects are observed for the deletion mutant Δ143-145 of the Wuhan S-protein, thus supporting localization of the binding site in the N-terminal domain (NTD). The glycomimetics Oseltamivir and Zanamivir bind weakly to the S-protein of both virus strains. Binding of blood group antigens to the Wuhan S-protein cannot be confirmed by STD NMR. Using 1 H,15 N TROSY HSQC-based chemical shift perturbation (CSP) experiments, we excluded binding of any of the ligands studied to the RBD of the Wuhan S-protein. Our results put reported data on glycan binding into perspective and shed new light on the potential role of glycan-binding to the S-protein.


Subject(s)
COVID-19 , Severe Acute Respiratory Syndrome , Humans , Spike Glycoprotein, Coronavirus , Binding Sites , Polysaccharides , Magnetic Resonance Spectroscopy , Protein Binding
10.
Value Health ; 25(12): 2028-2033, 2022 12.
Article in English | MEDLINE | ID: mdl-35690519

ABSTRACT

OBJECTIVES: The aim of this study was to show how the US government could save approximately 47 000 patients with chronic kidney failure each year from suffering on dialysis and premature death by compensating living kidney donors enough to completely end the kidney shortage. METHODS: Supply and demand analysis was used to estimate the number of donated kidneys needed to end the kidney shortage and the level of compensation required to encourage this number of donations. These results were then input into a detailed cost-benefit analysis to estimate the economic value of kidney transplantation to (1) the average kidney recipient and their caregiver, (2) taxpayers, and (3) society in general. RESULTS: We estimate half of patients diagnosed with kidney failure each year-approximately 62 000 patients-could be saved from suffering on dialysis and premature death if they could receive an average of 1½ kidney transplants. However, currently there are only enough donated kidneys to save approximately 15 000 patients. To encourage sufficient donations to save the other 47 000 patients, the government would have to compensate living kidney donors approximately $77 000 (±50%) per donor. The value of transplantation to an average kidney recipient (and caregiver) would be approximately $1.5 million, and the savings from the recipient not needing expensive dialysis treatments would be approximately $1.2 million. CONCLUSIONS: This analysis reveals the huge benefit that compensating living kidney donors would provide to patients with kidney failure and their caregivers and, conversely, the huge cost that is being imposed on these patients and their families by the current legal prohibition against such compensation.


Subject(s)
Kidney Failure, Chronic , Kidney Transplantation , Humans , United States , Cost-Benefit Analysis , Living Donors , Kidney Failure, Chronic/surgery , Renal Dialysis
11.
J Occup Environ Hyg ; 19(5): 295-301, 2022 05.
Article in English | MEDLINE | ID: mdl-35286244

ABSTRACT

Ventilation plays an important role in mitigating the risk of airborne virus transmission in university classrooms. During the early phase of the COVID-19 pandemic, methods to assess classrooms for ventilation adequacy were needed. The aim of this paper was to compare the adequacy of classroom ventilation determined through an easily accessible, simple, quantitative measure of air changes per hour (ACH) to that determined through qualitative "expert judgment" and recommendations from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and the American Conference of Governmental Industrial Hygienists (ACGIH)®. Two experts, ventilation engineers from facilities maintenance, qualitatively ranked buildings with classrooms on campus with regard to having "acceptable classroom ventilation." Twelve lecture classrooms were selected for further testing, including a mix of perceived adequate/inadequate ventilation. Total air change per hour (ACH) was measured to quantitatively assess ventilation through the decay of carbon dioxide in the front and rear of these classrooms. The outdoor ACH was calculated by multiplying the total ACH by the outdoor air fraction. The classrooms in a building designed to the highest ASHRAE standards (62.1 2004) did not meet ACGIH COVID-19 recommendations. Four of the classrooms met the ASHRAE criteria. However, a classroom that was anticipated to fail based on expert knowledge met the ASHRAE and ACGIH criteria. Only two classrooms passed stringent ACGIH recommendations (outdoor ACH > 6). None of the classrooms that passed ACGIH criteria were originally expected to pass. There was no significant difference in ACH measured in the front and back of classrooms, suggesting that all classrooms were well mixed with no dead zones. From these results, schools should assess classroom ventilation considering a combination of classroom design criteria, expert knowledge, and ACH measurements.


Subject(s)
Air Pollution, Indoor , COVID-19 , Air Pollution, Indoor/prevention & control , COVID-19/epidemiology , Humans , Pandemics , Schools , Universities , Ventilation/methods
12.
J Occup Environ Hyg ; 19(6): 343-352, 2022 06.
Article in English | MEDLINE | ID: mdl-35286249

ABSTRACT

Worker exposure to occupational hazards is traditionally measured by equipping workers with wearable exposure monitors. An emerging alternative measurement first generates time-varying hazard maps from permanent monitors within the facility, then estimating worker exposure by integrating hazard levels traversed in map, following the tracked movement of workers. Complex environments may require many monitors to produce a hazard map with the necessary accuracy, but effective interpolation functions can reduce the required number of monitors needed. This work assesses the effectiveness of three models for accurately interpolating hazard levels among monitors: a traditional Kriging model, a physics-based model, and a hybrid model that combines the Kriging and physics-based models. The effectiveness of each interpolation function was tested with sound levels collected in four environmental settings. These detailed experimental data were used to generate over 10,000 simulation trials, where each trial configured the experimental data into a unique arrangement of simulated monitoring and sampling positions. For each simulation trial, the effectiveness of the three models was assessed with the root mean square error of the sound levels at the simulated sampling positions, using the simulated monitoring positions as input. The interpolated values between the monitored positions were analyzed separately from the extrapolated values beyond the monitored positions. The hybrid model consistently reported among the lowest errors in each trial. The Kriging model performed best for the densest networks (those with the most monitors). Even in these cases, the hybrid model performed within 10% of the Kriging model with less than a third of the monitors. The experiment demonstrates that the hybrid model is highly effective at estimating hazardous sound levels; future work may demonstrate similar advantages for gas and aerosol hazards.


Subject(s)
Environmental Monitoring , Physics , Humans , Spatial Analysis
13.
Clin Transplant ; 35(8): e14292, 2021 08.
Article in English | MEDLINE | ID: mdl-33749935

ABSTRACT

To predict whether the COVID-19 pandemic and transplant center responses could have resulted in preventable deaths, we analyzed registry information of the US end-stage renal disease (ESRD) patient population awaiting kidney transplantation. Data were from the Organ Procurement and Transplantation Network (OPTN), the US Centers for Disease Control and Prevention, and the United States Renal Data System. Based on 2019 OPTN reports, annualized reduction in kidney transplantation of 25%-100% could result in excess deaths of wait-listed (deceased donor) transplant candidates from 84 to 337 and living donor candidate excess deaths from 35 to 141 (total 119-478 potentially preventable deaths of transplant candidates). Changes in transplant activity due to COVID-19 varied with some centers shutting down while others simply heeded known or suspected pandemic risks. Understanding potential excess mortality for ESRD transplant candidates when circumstances compel curtailment of transplant activity may inform policy and procedural aspects of organ transplant systems allowing ways to best inform patients and families as to potential risks in shuttering organ transplant activity. Considering that more than 700 000 Americans have ESRD with 100 000 awaiting a kidney transplant, our highest annual estimate of 478 excess total deaths from postponing kidney transplantation seems modest.


Subject(s)
COVID-19 , Kidney Failure, Chronic , Tissue and Organ Procurement , Humans , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/surgery , Living Donors , Pandemics , SARS-CoV-2 , United States/epidemiology , Waiting Lists
14.
Langenbecks Arch Surg ; 406(6): 1831-1838, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34021417

ABSTRACT

PURPOSE: Internal hernias (IH) are frequent complications after laparoscopic Roux-en-Y gastric bypass (LRYGB). Closure of the jejunal mesenteric and the Petersen defect reduces IH incidence in prospective and retrospective trials. This study investigates whether closing the jejunal mesenteric space alone by non-absorbable suture and splitting the omentum can be beneficial to prevent IH after LRYGB. METHODS: Observational cohort study of 785 patients undergoing linear LRYGB including omental split at a single institution, with 493 patients without jejunal mesenteric defect closure and 292 patients with closure by non-absorbable suture, and a minimal follow-up of 2 years. Patients were assessed for appearance and severity of IH. Additionally, open mesenteric gaps without herniated bowel as well as early obstructions due to kinking of the entero-enterostomy (EE) were explored. RESULTS: Through primary mesenteric defect closure, the rate of manifest jejunal mesenteric and Petersen IH could be reduced from 6.5 to 3.8%, but without reaching statistical significance. The most common location for an IH was the jejunal mesenteric space, where defect closure during primary surgery reduced the rate of IH from 5.3 to 2.4%. Higher weight loss seemed to increase the risk of developing an IH. CONCLUSION: The closure of the jejunal mesenteric defect by non-absorbable suture may reduce the rate of IH at the jejunal mesenteric space after LRYGB. However, the beneficial effect in our collective is smaller than expected, particularly in patients with good weight loss. The Petersen IH rate remained low by consequent T-shape split of the omentum without suturing of the defect.


Subject(s)
Gastric Bypass , Hernia, Abdominal , Laparoscopy , Obesity, Morbid , Gastric Bypass/adverse effects , Hernia, Abdominal/epidemiology , Hernia, Abdominal/etiology , Hernia, Abdominal/prevention & control , Humans , Incidence , Internal Hernia , Obesity, Morbid/surgery , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Prospective Studies , Retrospective Studies , Sutures
15.
Molecules ; 26(8)2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33917179

ABSTRACT

Noroviruses are the major cause of viral gastroenteritis and re-emerge worldwide every year, with GII.4 currently being the most frequent human genotype. The norovirus capsid protein VP1 is essential for host immune response. The P domain mediates cell attachment via histo blood-group antigens (HBGAs) in a strain-dependent manner but how these glycan-interactions actually relate to cell entry remains unclear. Here, hydrogen/deuterium exchange mass spectrometry (HDX-MS) is used to investigate glycan-induced protein dynamics in P dimers of different strains, which exhibit high structural similarity but different prevalence in humans. While the almost identical strains GII.4 Saga and GII.4 MI001 share glycan-induced dynamics, the dynamics differ in the emerging GII.17 Kawasaki 308 and rare GII.10 Vietnam 026 strain. The structural aspects of glycan binding to fully deamidated GII.4 P dimers have been investigated before. However, considering the high specificity and half-life of N373D under physiological conditions, large fractions of partially deamidated virions with potentially altered dynamics in their P domains are likely to occur. Therefore, we also examined glycan binding to partially deamidated GII.4 Saga and GII.4 MI001 P dimers. Such mixed species exhibit increased exposure to solvent in the P dimer upon glycan binding as opposed to pure wildtype. Furthermore, deamidated P dimers display increased flexibility and a monomeric subpopulation. Our results indicate that glycan binding induces strain-dependent structural dynamics, which are further altered by N373 deamidation, and hence hint at a complex role of deamidation in modulating glycan-mediated cell attachment in GII.4 strains.


Subject(s)
Capsid Proteins/chemistry , Molecular Dynamics Simulation , Polysaccharides/chemistry , Protein Interaction Domains and Motifs , Protein Multimerization , Amino Acids , Binding Sites , Humans , Norovirus , Protein Binding , Protein Conformation
16.
J Occup Environ Hyg ; 18(3): 139-148, 2021 03.
Article in English | MEDLINE | ID: mdl-33507840

ABSTRACT

Daily activities performed by music instructors generate high sound levels that could potentially lead to overexposure. Adverse outcomes associated with high-exposure to sound, such as hearing loss and tinnitus, can be especially devastating to music instructors as hearing is essential to both job performance and career reward. The primary objective of this study was to compare sound exposures of music instructors to recommended exposure limits. Secondary objectives were to identify high-exposure activities and to evaluate potential similar exposure groups by examining between- and within-worker exposure variability. Personal sound exposure measurements from music instructors were collected using dosimeters during full workdays for up to 4 weeks over multiple semesters at a university's school of music. Study participants completed an activity log to record work-related activities throughout each day of sampling. Dosimeters logged 1-sec sound equivalent levels in A-weighted decibels. These data were used to calculate 8-hr time-weighted averages, daily dose, and activity-specific contributions to that dose to determine if daily exposures exceeded the recommended limit of 85 dBA and to identify high-exposure activities that could be targeted for future intervention. Seventeen participants were sampled for a total of 200 days. Approximately one-third of daily exposures exceeded recommended limits. The groups with the highest exposures were brass and conducting instructors. Conductors experienced the highest between-day variability in daily exposures. Activities that contributed the most to daily dose included group rehearsals, personal practice sessions, and performances, while classes and administrative work did not substantially contribute to daily dose. Daily exposures were highly variable, ranging from 60-95 dBA (mean = 81 dBA, sd = 8 dBA), and were influenced by instructional area and musical activity. Future exposure assessments for music instructors should include sampling for multiple days, and those above-recommended limits should be placed into hearing conservation programs.


Subject(s)
Music , Noise, Occupational , Occupational Exposure , Tinnitus , Humans , Sound
17.
J Occup Environ Hyg ; 18(2): 65-71, 2021 02.
Article in English | MEDLINE | ID: mdl-33406010

ABSTRACT

A quantitative fit test is performed using a benchtop instrument (e.g., TSI PortaCount) to assess the fit factor provided by a respirator when assigned to a worker. There are no wearable instruments on the market to measure protection factors while the respirator is in use. The aim of this study is to evaluate two new, wearable, quantitative instruments-a dual-channel optical particle counter (DC OPC) and a dual-channel condensation particle counter (DC CPC)-that would enable in-situ, real-time measurement of respirator workplace protection factor. Respirator laboratory protection factors measured by the new instruments were compared to those measured with the TSI PortaCount on one test subject for three test aerosols (sodium chloride, incense, ambient) at target laboratory protection factors of 100, 300, and 1,000 for sodium chloride and ambient, and 75 and 500 for incense. Three replicates were performed for each test condition. Data were analyzed with a two-sided paired t-test at a significance level of 0.05. Laboratory protection factors measured with the DC CPC agree with those measured with the PortaCount whereas those from the DC OPC generally do not. Mean laboratory protection factors derived from the DC CPC are only statistically significantly different for mean values of a laboratory protection factor at ambient conditions for a target laboratory protection factor of 300 (p = 0.02) and for incense at a target laboratory protection factor of 75 (p = 0.03). Although statistically significant, the difference in laboratory protection factors derived from the DC CPC are not substantial in practice and may be explained by systematic uncertainty. In contrast, the DC OPC reports substantially larger mean laboratory protection factors, differing by about half an order of magnitude in extreme cases, and statistically significantly different mean laboratory protection factors for the sodium chloride aerosol for target laboratory protection factors of 100 and 300 (p = 0.01 and p = 0.01).


Subject(s)
Occupational Exposure , Respiratory Protective Devices , Aerosols , Laboratories , Occupational Exposure/prevention & control , Ventilators, Mechanical
18.
Genes Chromosomes Cancer ; 59(2): 96-105, 2020 02.
Article in English | MEDLINE | ID: mdl-31469468

ABSTRACT

Tenosynovial giant cell tumors (TGCTs) are characterized by rearrangements of CSF1, thought to drive overexpression of macrophage colony-stimulating factor (CSF1), thereby promoting tumor growth and recruitment of non-neoplastic mononuclear and multinucleated inflammatory cells. While fusions to collagen promoters have been described, the mechanism of CSF1 overexpression has been unclear in a majority of cases. Two cohorts of TGCT were investigated for CSF1 rearrangements using fluorescence in situ hybridization (FISH) and either RNA-seq or DNA-seq with Sanger validation. The study comprised 39 patients, including 13 localized TGCT, 21 diffuse TGCT, and five of unspecified type. CSF1 rearrangements were identified by FISH in 30 cases: 13 translocations, 17 3' deletions. Sequencing confirmed CSF1 breakpoints in 28 cases; in all 28 the breakpoint was found to be downstream of exon 5, replacing or deleting a long 3' UTR containing known miRNA and AU-rich element negative regulatory sequences. We also confirmed the presence of CBL exon 8-9 mutations in six of 21 cases. In conclusion, TGCT in our large cohort were characterized by variable alterations, all of which led to truncation of the 3' end of CSF1, instead of the COL6A3-CSF1 fusions previously reported in some TGCTs. The diversity of fusion partners but consistent integrity of CSF1 functional domains encoded by exons 1-5 support a hypothesis that CSF1 overexpression results from transcription of a truncated form of CSF1 lacking 3' negative regulatory sequences. The presence of CBL mutations affecting the linker and RING finger domain suggests an alternative mechanism for increased CSF1/CSF1R signaling in some cases.


Subject(s)
Giant Cell Tumor of Tendon Sheath/genetics , Macrophage Colony-Stimulating Factor/genetics , 3' Untranslated Regions , Adult , Aged , Cohort Studies , Exons , Female , Giant Cell Tumor of Tendon Sheath/diagnosis , Giant Cell Tumor of Tendon Sheath/metabolism , Humans , In Situ Hybridization, Fluorescence/methods , Macrophage Colony-Stimulating Factor/metabolism , Male , Middle Aged , Translocation, Genetic
19.
Am J Transplant ; 20(4): 1087-1094, 2020 04.
Article in English | MEDLINE | ID: mdl-31667990

ABSTRACT

Using 5 years of US organ procurement organization (OPO) data, we determined the cost of recovering a viable (ie, transplanted) kidney for each of 51 OPOs. We also examined the effects on OPO costs of the recovery of nonviable (ie, discarded) kidneys and other OPO metrics. Annual cost reports from 51 independent OPOs were used to determine the cost per recovered kidney for each OPO. A quadratic regression model was employed to estimate the relationship between the cost of kidneys and the number of viable kidneys recovered, as well as other OPO performance indicators. The cost of transplanted kidneys at individual OPOs ranged widely from $24 000 to $56 000, and the average was $36 000. The cost of a viable kidney tended to decline with the number of kidneys procured up to 549 kidneys per year and then increase. Of the total 81 401 kidneys recovered, 66 454 were viable and 14 947 (18.4%) were nonviable. The costs of kidneys varied widely over the OPOs studied, and costs were a function of the recovered number of viable and nonviable organs, local cost levels, donation after cardiac death, year, and Standardized Donor Rate Ratio. Cost increases were 3% per year.


Subject(s)
Kidney Transplantation , Tissue and Organ Procurement , Death , Humans , Kidney , Tissue Donors
20.
Chembiochem ; 21(7): 1007-1021, 2020 04 01.
Article in English | MEDLINE | ID: mdl-31644826

ABSTRACT

Bile acids have been reported as important cofactors promoting human and murine norovirus (NoV) infections in cell culture. The underlying mechanisms are not resolved. Through the use of chemical shift perturbation (CSP) NMR experiments, we identified a low-affinity bile acid binding site of a human GII.4 NoV strain. Long-timescale MD simulations reveal the formation of a ligand-accessible binding pocket of flexible shape, allowing the formation of stable viral coat protein-bile acid complexes in agreement with experimental CSP data. CSP NMR experiments also show that this mode of bile acid binding has a minor influence on the binding of histo-blood group antigens and vice versa. STD NMR experiments probing the binding of bile acids to virus-like particles of seven different strains suggest that low-affinity bile acid binding is a common feature of human NoV and should therefore be important for understanding the role of bile acids as cofactors in NoV infection.


Subject(s)
Bile Acids and Salts/metabolism , Capsid Proteins/metabolism , Norovirus/metabolism , Animals , Bile Acids and Salts/chemistry , Binding Sites , Caliciviridae Infections/pathology , Caliciviridae Infections/virology , Capsid Proteins/chemistry , Dimerization , Humans , Ligands , Molecular Dynamics Simulation , Nuclear Magnetic Resonance, Biomolecular , Protein Binding , Protein Structure, Tertiary
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