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1.
BMC Genomics ; 25(1): 789, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160478

RESUMO

BACKGROUND: Detecting very minor (< 1%) subpopulations using next-generation sequencing is a critical need for multiple applications, including the detection of drug resistant pathogens and somatic variant detection in oncology. A recently available sequencing approach termed 'sequencing by binding (SBB)' claims to have higher base calling accuracy data "out of the box." This paper evaluates the utility of using SBB for the detection of ultra-rare drug resistant subpopulations in Mycobacterium tuberculosis (Mtb) using a targeted amplicon assay and compares the performance of SBB to single molecule overlapping reads (SMOR) error corrected sequencing by synthesis (SBS) data. RESULTS: SBS displayed an elevated error rate when compared to SMOR error-corrected SBS and SBB techniques. SMOR error-corrected SBS and SBB technologies performed similarly within the linear range studies and error rate studies. CONCLUSIONS: With lower sequencing error rates within SBB sequencing, this technique looks promising for both targeted and unbiased whole genome sequencing, leading to the identification of minor (< 1%) subpopulations without the need for error correction methods.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Mycobacterium tuberculosis , Mycobacterium tuberculosis/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Humanos , Sequenciamento Completo do Genoma/métodos
2.
Phys Rev Lett ; 131(26): 262701, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38215364

RESUMO

Nuclear isomer effects are pivotal in understanding nuclear astrophysics, particularly in the rapid neutron-capture process where the population of metastable isomers can alter the radioactive decay paths of nuclei produced during astrophysical events. The ß-decaying isomer ^{128m}Sb was identified as potentially impactful since the ß-decay pathway along the A=128 isobar funnels into this state bypassing the ground state. We report the first direct mass measurements of the ^{128}Sb isomer and ground state using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory. We find mass excesses of -84564.8(25) keV and -84608.8(21) keV, respectively, resulting in an excitation energy for the isomer of 43.9(33) keV. These results provide the first key nuclear data input for understanding the role of ^{128m}Sb in nucleosynthesis, and we show that it will influence the flow of the rapid neutron-capture process.

3.
Appl Environ Microbiol ; 87(13): e0031921, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33893109

RESUMO

Tick-borne diseases in California include Lyme disease (caused by Borrelia burgdorferi), infections with Borrelia miyamotoi, and human granulocytic anaplasmosis (caused by Anaplasma phagocytophilum). We surveyed multiple sites and habitats (woodland, grassland, and coastal chaparral) in California to describe spatial patterns of tick-borne pathogen prevalence in western black-legged ticks (Ixodes pacificus). We found that several species of Borrelia-B. burgdorferi, Borrelia americana, and Borrelia bissettiae-were observed in habitats, such as coastal chaparral, that do not harbor obvious reservoir host candidates. Describing tick-borne pathogen prevalence is strongly influenced by the scale of surveillance: aggregating data from individual sites to match jurisdictional boundaries (e.g., county or state) can lower the reported infection prevalence. Considering multiple pathogen species in the same habitat allows a more cohesive interpretation of local pathogen occurrence. IMPORTANCE Understanding the local host ecology and prevalence of zoonotic diseases is vital for public health. Using tick-borne diseases in California, we show that there is often a bias to our understanding and that studies tend to focus on particular habitats, e.g., Lyme disease in oak woodlands. Other habitats may harbor a surprising diversity of tick-borne pathogens but have been neglected, e.g., coastal chaparral. Explaining pathogen prevalence requires descriptions of data on a local scale; otherwise, aggregating the data can misrepresent the local dynamics of tick-borne diseases.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Vetores Aracnídeos/microbiologia , Borrelia/isolamento & purificação , Ixodes/microbiologia , Animais , California , Ecossistema , Larva/microbiologia , Ninfa/microbiologia
4.
Phys Rev Lett ; 126(4): 042501, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33576685

RESUMO

We report high-precision mass measurements of ^{50-55}Sc isotopes performed at the LEBIT facility at NSCL and at the TITAN facility at TRIUMF. Our results provide a substantial reduction of their uncertainties and indicate significant deviations, up to 0.7 MeV, from the previously recommended mass values for ^{53-55}Sc. The results of this work provide an important update to the description of emerging closed-shell phenomena at neutron numbers N=32 and N=34 above proton-magic Z=20. In particular, they finally enable a complete and precise characterization of the trends in ground state binding energies along the N=32 isotone, confirming that the empirical neutron shell gap energies peak at the doubly magic ^{52}Ca. Moreover, our data, combined with other recent measurements, do not support the existence of a closed neutron shell in ^{55}Sc at N=34. The results were compared to predictions from both ab initio and phenomenological nuclear theories, which all had success describing N=32 neutron shell gap energies but were highly disparate in the description of the N=34 isotone.

6.
Int J Health Geogr ; 18(1): 9, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064416

RESUMO

BACKGROUND: Tick-borne disease is the result of spillover of pathogens into the human population. Traditionally, literature has focused on characterization of tick-borne disease pathogens and ticks in their sylvatic cycles. A limited amount of research has focused on human-tick exposure in this system, especially in the Northeastern United States. Human-tick interactions are crucial to consider when assessing the risk of tick-borne disease since a tick bite is required for spillover to occur. METHODS: Citizen scientists collected ticks from the Northeastern US through a free nationwide program. Submitted ticks were identified to species, stage, and sex. Blacklegged ticks, Ixodes scapularis, were tested for the presence of Borrelia burgdorferi sensu lato (s.l.) and hard-tick relapsing fever Borrelia. Seasonality of exposure and the citizen science activity during tick exposure was recorded by the citizen scientist. A negative binomial model was fit to predict county level CDC Lyme disease cases in 2016 using citizen science Ixodes scapularis submissions, state, and county population as predictor variables. RESULTS: A total of 3740 submissions, comprising 4261 ticks, were submitted from the Northeastern US and were reported to be parasitizing humans. Of the three species submitted, blacklegged ticks were the most prevalent followed by American dog ticks and lone star ticks. Submissions peaked in May with the majority of exposure occurring during every-day activities. The most common pathogen in blacklegged ticks was B. burgdorferi s.l. followed by hard-tick relapsing fever Borrelia. Negative binomial model performance was best in New England states followed by Middle Atlantic states. CONCLUSIONS: Citizen science provides a low-cost and effective methodology for describing the seasonality and characteristics of human-tick exposure. In the Northeastern US, everyday activities were identified as a major mechanism for tick exposure, supporting the role of peri-domestic exposure in tick-borne disease. Citizen science provides a method for broad pathogen and tick surveillance, which is highly related to human disease, allowing for inferences to be made about the epidemiology of tick-borne disease.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Ciência do Cidadão/métodos , Doença de Lyme/epidemiologia , Picadas de Carrapatos/epidemiologia , Infestações por Carrapato/epidemiologia , Animais , Ciência do Cidadão/tendências , Humanos , Ixodes , Doença de Lyme/diagnóstico , New England/epidemiologia , Especificidade da Espécie , Picadas de Carrapatos/diagnóstico , Infestações por Carrapato/diagnóstico
7.
Phys Rev Lett ; 120(26): 262701, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30004755

RESUMO

The rare-earth peak in the r-process abundance pattern depends sensitively on both the astrophysical conditions and subtle changes in nuclear structure in the region. This work takes an important step towards elucidating the nuclear structure and reducing the uncertainties in r-process calculations via precise atomic mass measurements at the JYFLTRAP double Penning trap. ^{158}Nd, ^{160}Pm, ^{162}Sm, and ^{164-166}Gd have been measured for the first time, and the precisions for ^{156}Nd, ^{158}Pm, ^{162,163}Eu, ^{163}Gd, and ^{164}Tb have been improved considerably. Nuclear structure has been probed via two-neutron separation energies S_{2n} and neutron pairing energy metrics D_{n}. The data do not support the existence of a subshell closure at N=100. Neutron pairing has been found to be weaker than predicted by theoretical mass models. The impact on the calculated r-process abundances has been studied. Substantial changes resulting in a smoother abundance distribution and a better agreement with the solar r-process abundances are observed.

8.
Br J Dermatol ; 174(3): 594-601, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26473312

RESUMO

BACKGROUND: Oral propranolol is widely prescribed as first-line treatment for infantile haemangiomas (IHs). Anecdotally, prescribing practice differs widely between centres. OBJECTIVES: The Propranolol In the Treatment of Complicated Haemangiomas (PITCH) Taskforce was founded to establish patterns of use of propranolol in IHs. METHODS: Participating centres entered data on all of their patients who had completed treatment with oral propranolol for IHs, using an online data capture tool. RESULTS: The study cohort comprised 1097 children from 39 centres in eight European countries. 76·1% were female and 92·8% had a focal IH, with the remainder showing a segmental, multifocal or indeterminate pattern. The main indications for treatment were periocular location (29·3%), risk of cosmetic disfigurement (21·1%) and ulceration and bleeding (20·6%). In total 69·2% of patients were titrated up to a maintenance regimen, which consisted of 2 mg kg(-1) per day (85·8%) in the majority of cases. 91·4% of patients had an excellent or good response to treatment. Rebound growth occurred in 14·1% upon stopping, of whom 53·9% were restarted and treatment response was recaptured in 91·6% of cases. While there was no significant difference in the treatment response, comparing a daily maintenance dose of < 2 mg kg(-1) vs. 2 mg kg(-1) vs. > 2 mg kg(-1) , the risk of adverse events was significantly higher: odds ratio (OR) 1 vs. adjusted OR 0·70, 95% confidence interval (CI) 0·33-1·50, P = 0·36 vs. OR 2·38, 95% CI 1·04-5·46, P = 0·04, Ptrend < 0·001. CONCLUSIONS: The PITCH survey summarizes the use of oral propranolol across 39 European centres, in a variety of IH phases, and could be used to inform treatment guidelines and the design of an interventional study.


Assuntos
Antineoplásicos/administração & dosagem , Hemangioma/tratamento farmacológico , Propranolol/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Antineoplásicos/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Masculino , Propranolol/efeitos adversos , Resultado do Tratamento
9.
Proc Natl Acad Sci U S A ; 109(10): 3623-7, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22308483

RESUMO

For prevention of Streptococcus pneumoniae (pneumococcus) infections in infancy, protein-conjugated capsular polysaccharide vaccines provide serotype-specific, antibody-mediated immunity but do not cover all of the 90+ capsule serotypes. Therefore, microbiologists have sought protective noncapsular antigens common to all strains. Alternatively, we investigated killed cells of a noncapsulated strain, which expose many such common antigens. Given to mice intranasally, this vaccine elicits antibody-independent, CD4+ T lymphocyte-dependent accelerated clearance of pneumococci of various serotypes from the nasopharynx mediated by the cytokine IL-17A. Such immunity may reproduce the natural resistance that develops in infants before capsular antibodies arise. Given by injection, the killed cell vaccine induces bifunctional immunity: plasma antibodies protective against fatal pneumonia challenge, as well as IL-17A-mediated nasopharyngeal clearance. Human testing of this inexpensive candidate vaccine by intramuscular injection is planned. Bacterial cellular vaccines are complex--a challenge for reproducibility. However, when several known protective antigens were deleted, the killed pneumococcal vaccine was still protective. This antigenic redundancy may prevent vaccine escape variants by recombinational loss, which is frequent in pneumococcus. Biochemically defined immunogens with bifunctional activity have also been devised. These immunogens are three-component conjugates in which cell wall teichoic acid (a common antigen capable of T cell activation) is coupled to a genetic fusion of two common pneumococcal proteins: a protective surface antigen and a derivative of pneumolysin, which provides TLR4 agonist activity and induces antitoxic immunity. Such constructs induce accelerated clearance when given intranasally and induce both immune mechanisms when injected. The defined composition permits analysis of structure-function activity.


Assuntos
Imunidade Humoral/fisiologia , Infecções Pneumocócicas/prevenção & controle , Streptococcus pneumoniae/metabolismo , Animais , Antígenos de Superfície/química , Linfócitos B/imunologia , Vacinas Bacterianas/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Humanos , Imunidade Celular , Interleucina-17/metabolismo , Camundongos , Mucosa/patologia , Linfócitos T/imunologia
10.
Int J Obes (Lond) ; 38(9): 1248-50, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24441037

RESUMO

Rapid detection of shifts in substrate utilization and energy balance would provide a compelling biofeedback tool for individuals attempting weight loss. As a proof of concept, we tested whether the natural abundance of exhaled carbon stable isotope ratios (breath δ(13)C) reflects shifts between negative and positive energy balance. Volunteers (n=5) consumed a 40% energy-restricted diet for 6 days followed by 50% excess on day 7. Breath was sampled immediately before and 1 h and 2 h after breakfast, lunch and dinner. Exhaled breath δ(13)C values were measured by cavity ring-down spectroscopy. Using repeated measures analysis of variance (ANOVA) followed by Dunnett's contrasts, pre-breakfast breath values on days 2-6 were compared with day 1, and postprandial day 7 time points were compared with pre-breakfast day 7. Energy restriction diminished pre-breakfast breath δ(13)C by day 3 (P<0.05). On day 7, increased energy intake was first detected immediately before dinner (-23.8±0.6 vs -21.9±0.7‰, P=0.002 (means±s.d.)), and breath δ(13)C remained elevated at least 2 h post dinner. In conclusion, when shifting between negative and positive energy balance, breath δ(13)C showed anticipated isotopic changes. Although additional research is needed to determine specificity and repeatability, this method may provide a biomarker for marked increases in caloric intake.


Assuntos
Testes Respiratórios , Dióxido de Carbono/metabolismo , Isótopos de Carbono/metabolismo , Metabolismo Energético , Período Pós-Prandial , Adulto , Ingestão de Energia , Comportamento Alimentar , Humanos , Análise Espectral/métodos , Fatores de Tempo , Redução de Peso
11.
Br J Dermatol ; 170(3): 730-4, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24125073

RESUMO

BACKGROUND: Primary cutaneous amyloidosis of the penis is a rare entity. OBJECTIVES: We describe two cases of primary penile cutaneous amyloidosis presenting as localized lesions on the penis and not associated with systemic amyloidosis. METHODS: A comprehensive literature review of all published cases. RESULTS: The rarest form of cutaneous amyloidosis, nodular amyloidosis, is the most frequent presentation of penis-limited cutaneous amyloid with a low incidence of systemic disease progression. CONCLUSIONS: Although primary nodular amyloidosis is a rare entity it seems to be the most frequent presentation of penile-limited cutaneous disease, with a low incidence of systemic involvement.


Assuntos
Amiloidose Familiar/patologia , Doenças do Pênis/patologia , Dermatopatias Genéticas/patologia , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Med Primatol ; 43(2): 122-4, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24400996

RESUMO

BACKGROUND: Pathogenic Escherichia coli has been identified as an etiologic agent in humans causing acute diarrhea or even death but has been rarely reported in non-human primates (NHP). An outbreak of diarrhea occurred in an outdoor-housed NHP colony over a period of 2 months with an attack rate of 29%. METHODS: Bacterial culture and PCR were performed on the fecal specimens to identify enteroinvasive E. coli (EIEC) and Enterohemorrhagic E. coli (EHEC) in the NHPs. RESULTS: By random sampling of 10% of fecal samples of diarrheal cases, four cases of EIEC in rhesus macaques and two cases of EHEC in cynomolgus macaques were confirmed. CONCLUSION: This is the first time EIEC and EHEC have been reported in NHPs associated with diarrhea. The primary source of infection could not be determined.


Assuntos
Animais de Zoológico , Diarreia/veterinária , Surtos de Doenças/veterinária , Infecções por Escherichia coli/veterinária , Escherichia coli/isolamento & purificação , Macaca fascicularis , Macaca mulatta , Doenças dos Macacos/epidemiologia , Animais , Contagem de Colônia Microbiana/veterinária , Diarreia/epidemiologia , Diarreia/microbiologia , Diarreia/terapia , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/terapia , Doenças dos Macacos/microbiologia , Doenças dos Macacos/terapia , Reação em Cadeia da Polimerase/veterinária , Estados Unidos/epidemiologia
13.
Sci Rep ; 14(1): 1311, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225347

RESUMO

Coccidioides is the fungal causative agent of Valley fever, a primarily pulmonary disease caused by inhalation of fungal arthroconidia, or spores. Although Coccidioides has been an established pathogen for 120 years and is responsible for hundreds of thousands of infections per year, little is known about when and where infectious Coccidioides arthroconidia are present within the ambient air in endemic regions. Long-term air sampling programs provide a means to investigate these characteristics across space and time. Here we present data from > 18 months of collections from 11 air sampling sites across the Phoenix, Arizona, metropolitan area. Overall, prevalence was highly variable across space and time with no obvious spatial or temporal correlations. Several high prevalence periods were identified at select sites, with no obvious spatial or temporal associations. Comparing these data with weather and environmental factor data, wind gusts and temperature were positively associated with Coccidioides detection, while soil moisture was negatively associated with Coccidioides detection. These results provide critical insights into the frequency and distribution of airborne arthroconidia and the associated risk of inhalation and potential disease that is present across space and time in a highly endemic locale.


Assuntos
Coccidioidomicose , Coccidioidomicose/epidemiologia , Coccidioidomicose/microbiologia , Coccidioides , Arizona/epidemiologia , Tempo (Meteorologia) , Temperatura , Esporos Fúngicos
14.
medRxiv ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38562876

RESUMO

Background: Most seasonally circulating enteroviruses result in asymptomatic or mildly symptomatic infections. In rare cases, however, infection with some subtypes can result in paralysis or death. Of the 300 subtypes known, only poliovirus is reportable, limiting our understanding of the distribution of other enteroviruses that can cause clinical disease. Objective: The overarching objectives of this study were to: 1) describe the distribution of enteroviruses in Arizona during the late summer and fall of 2022, the time of year when they are thought to be most abundant, and 2) demonstrate the utility of viral pan-assay approaches for semi-agnostic discovery that can be followed up by more targeted assays and phylogenomics. Methods: This study utilizes pooled nasal samples collected from school-aged children and long-term care facility residents, and wastewater from multiple locations in Arizona during July-October of 2022. We used PCR to amplify and sequence a region common to all enteroviruses, followed by species-level bioinformatic characterization using the QIIME 2 platform. For Enterovirus-D68 (EV-D68), detection was carried out using RT-qPCR, followed by confirmation using near-complete whole EV-D68 genome sequencing using a newly designed tiled amplicon approach. Results: In the late summer and early fall of 2022, multiple enterovirus species were identified in Arizona wastewater, with Coxsackievirus A6, EV-D68, and Coxsackievirus A19 composing 86% of the characterized reads sequenced. While EV-D68 was not identified in pooled human nasal samples, and the only reported acute flaccid myelitis case in Arizona did not test positive for the virus, an in-depth analysis of EV-D68 in wastewater revealed that the virus was circulating from August through mid-October. A phylogenetic analysis on this relatively limited dataset revealed just a few importations into the state, with a single clade indicating local circulation. Significance: This study further supports the utility of wastewater-based epidemiology to identify potential public health threats. Our further investigations into EV-D68 shows how these data might help inform healthcare diagnoses for children presenting with concerning neurological symptoms.

15.
Int J Obes (Lond) ; 37(5): 678-84, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22665137

RESUMO

OBJECTIVE: Consumption of high-fat diet exerts adverse effects on learning and memory formation, which is linked to impaired hippocampal function. Activation of glucagon-like peptide-1 (GLP-1) signalling ameliorates detrimental effects of obesity-diabetes on cognitive function; however, mechanisms underlying these beneficial actions remain unclear. This study examined effects of daily subcutaneous treatment with GLP-1 mimetic, Liraglutide, on synaptic plasticity, hippocampal gene expression and metabolic control in adult obese diabetic (ob/ob) mice. RESULTS: Long-term potentiation (LTP) induced by area CA1 was completely abolished in ob/ob mice compared with lean controls. Deleterious effects on LTP were rescued (P<0.001) with Liraglutide. Indeed, Liraglutide-treated mice exhibited superior LTP profile compared with lean controls (P<0.01). Expression of hippocampal brain-derived neurotropic factor and neurotrophic tyrosine kinase receptor-type 2 were not significantly different, but synaptophysin and Mash1 were decreased in ob/ob mice. Treatment with Liraglutide over 21 days increased expression of Mash1 in ob/ob mice (2.0-fold; P<0.01). These changes were associated with significantly reduced plasma glucose (21% reduction; P<0.05) and markedly improved plasma insulin concentrations (2.1- to 3.3-fold; P<0.05 to P<0.01). Liraglutide also significantly reduced the glycaemic excursion following an intraperitonal glucose load (area under curve (AUC) values: 22%; P<0.05) and markedly enhanced the insulin response to glucose (AUC values: 1.6-fold; P<0.05). O2 consumption, CO2 production, respiratory exchange ratio and energy expenditure were not altered by Liraglutide therapy. On day 21, accumulated food intake (32% reduction; P<0.05) and number of feeding bouts (32% reduction; P<0.05) were significantly reduced but simple energy restriction was not responsible for the beneficial actions of Liraglutide. CONCLUSION: Liraglutide elicits beneficial effects on metabolic control and synaptic plasticity in mice with severe obesity and insulin resistance mediated in part through increased expression of Mash1 believed to improve hippocampal neurogenesis and cell survival.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Hipocampo/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Obesidade/tratamento farmacológico , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Glicemia/metabolismo , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Dieta Hiperlipídica , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Glucose/metabolismo , Hipocampo/fisiopatologia , Hipoglicemiantes/administração & dosagem , Infusões Subcutâneas , Insulina/metabolismo , Resistência à Insulina , Liraglutida , Masculino , Glicoproteínas de Membrana/efeitos dos fármacos , Camundongos , Obesidade/metabolismo , Obesidade/fisiopatologia , Proteínas Tirosina Quinases/efeitos dos fármacos , Transdução de Sinais
17.
Sci Total Environ ; 857(Pt 1): 159165, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36195153

RESUMO

Previous studies show that SARS-CoV-2 waste shedding rates vary by community and are influenced by multiple factors; however, differences in shedding rates across multiple variants have yet to be evaluated. The purpose of this work is to build on previous research that evaluated waste shedding rates for early SARS-CoV-2 and the Delta variant, and update population level waste shedding rates for the more-recent Omicron variant in six communities. Mean SARS-CoV-2 waste shedding rates were found to increase with the predominance of the Delta variant and subsequently decrease with Omicron infections. Interestingly, the Delta stage had the highest mean shedding rates and was associated with the most severe disease symptoms reported in other clinical studies, while Omicron, exhibiting reduced symptoms, had the lowest mean shedding rates. Additionally, shedding rates were most consistent across communities during the Omicron stage. This is the first paper to identify waste shedding rates specific to the Omicron variant and fills a knowledge gap critical to disease prevalence modeling.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Águas Residuárias , COVID-19/epidemiologia
18.
PLoS Pathog ; 5(6): e1000476, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19521509

RESUMO

There are 91 known capsular serotypes of Streptococcus pneumoniae. The nasopharyngeal carriage prevalence of particular serotypes is relatively stable worldwide, but the host and bacterial factors that maintain these patterns are poorly understood. Given the possibility of serotype replacement following vaccination against seven clinically important serotypes, it is increasingly important to understand these factors. We hypothesized that the biochemical structure of the capsular polysaccharides could influence the degree of encapsulation of different serotypes, their susceptibility to killing by neutrophils, and ultimately their success during nasopharyngeal carriage. We sought to measure biological differences among capsular serotypes that may account for epidemiological patterns. Using an in vitro assay with both isogenic capsule-switch variants and clinical carriage isolates, we found an association between increased carriage prevalence and resistance to non-opsonic neutrophil-mediated killing, and serotypes that were resistant to neutrophil-mediated killing tended to be more heavily encapsulated, as determined by FITC-dextran exclusion. Next, we identified a link between polysaccharide structure and carriage prevalence. Significantly, non-vaccine serotypes that have become common in vaccinated populations tend to be those with fewer carbons per repeat unit and low energy expended per repeat unit, suggesting a novel biological principle to explain patterns of serotype replacement. More prevalent serotypes are more heavily encapsulated and more resistant to neutrophil-mediated killing, and these phenotypes are associated with the structure of the capsular polysaccharide, suggesting a direct relationship between polysaccharide biochemistry and the success of a serotype during nasopharyngeal carriage and potentially providing a method for predicting serotype replacement.


Assuntos
Cápsulas Bacterianas/química , Portador Sadio , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/imunologia , Animais , Cápsulas Bacterianas/genética , Portador Sadio/imunologia , Portador Sadio/microbiologia , Frutose/metabolismo , Glucose/metabolismo , Humanos , Modelos Lineares , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/imunologia , Vacinas Pneumocócicas/imunologia , Prevalência , Sorotipagem , Estatísticas não Paramétricas , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/patogenicidade
19.
Virus Res ; 306: 198604, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34662682

RESUMO

The 2020 pandemic has transformed the world and elicited thousands of studies to better understand the SARS-CoV-2 virus. Viral load has been a common measure to monitor treatment therapies and associate viral dynamics with patient outcomes; however, methods associated with viral load have varied across studies. These variations have the potential to sacrifice the accuracy of findings as they often do not account for inter-assay variation or variation across samples. In a retrospective study of nasopharyngeal samples, we found a significant amount of variation within the DNA and RNA targets; for example, across time within a single patient, there was an average of a 32-fold change. Further, we explore the impacts of host normalization on 94 clinical samples using the TGen Quantitative SARS-CoV-2 assay, finding that without host normalization samples with the same viral concentration can have up to 100-fold variation in the viral load.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/genética , Humanos , RNA Viral/genética , Estudos Retrospectivos , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Carga Viral
20.
mSphere ; 6(5): e0068221, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34585963

RESUMO

Tick-borne diseases have expanded over the last 2 decades as a result of shifts in tick and pathogen distributions. These shifts have significantly increased the need for accurate portrayal of real-time pathogen distributions and prevalence in hopes of stemming increases in human morbidity. Traditionally, pathogen distribution and prevalence have been monitored through case reports or scientific collections of ticks or reservoir hosts, both of which have challenges that impact the extent, availability, and accuracy of these data. Citizen science tick collections and testing campaigns supplement these data and provide timely estimates of pathogen prevalence and distributions to help characterize and understand tick-borne disease threats to communities. We utilized our national citizen science tick collection and testing program to describe the distribution and prevalence of four Ixodes-borne pathogens, Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia microti, across the continental United States. IMPORTANCE In the 21st century, zoonotic pathogens continue to emerge, while previously discovered pathogens continue to have changes within their distribution and prevalence. Monitoring these pathogens is resource intensive, requiring both field and laboratory support; thus, data sets are often limited within their spatial and temporal extents. Citizen science collections provide a method to harness the general public to collect samples, enabling real-time monitoring of pathogen distribution and prevalence.


Assuntos
Anaplasma phagocytophilum/fisiologia , Babesia microti/fisiologia , Borrelia/fisiologia , Ixodes/fisiologia , Anaplasma phagocytophilum/isolamento & purificação , Distribuição Animal , Animais , Babesia microti/isolamento & purificação , Borrelia/isolamento & purificação , Ciência do Cidadão , Interações Hospedeiro-Patógeno , Ixodes/microbiologia , Ixodes/parasitologia , Doenças Transmitidas por Carrapatos/transmissão , Estados Unidos
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