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1.
J Alzheimers Dis ; 100(1): 239-245, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848189

RESUMO

Background: Plasma and cerebrospinal fluid (CSF) levels of p-tau181 have been associated with Alzheimer's disease (AD). The retina and vitreous have shown measurable quantities of phosphorylated tau 181 (p-tau181). The aqueous humor, which can be collected during cataract surgery, may have measurable concentrations of p-tau181. Objective: To determine whether p-tau181 is detectable in the aqueous humor and if so, whether it is associated with other measures that might be consistent with AD such as higher plasma p-tau181 concentration and lower Montreal Cognitive Assessment (MoCA-BLIND version 7.1) score. Methods: Aqueous humor samples, blood samples, and MoCA-BLIND scores were collected from patients who did not carry a clinical diagnosis of cognitive impairment at the time of cataract surgery. Aqueous p-tau181 concentrations and plasma p-tau181 concentrations were then measured using ultra-sensitive single-molecule assay ELISA technology. A rank-transformed mixed-effects multivariate regression model was used to determine associations between aqueous concentrations, plasma concentrations, and MoCA-BLIND scores. Results: 16 eyes of 16 participants were enrolled with an average age of 71.6. Average MoCA-BLIND score was 20.6/22, average aqueous p-tau181 concentration was 6.4 pg/mL, and average plasma p-tau181 concentration was 3.1 pg/mL. Higher plasma p-tau181 was significantly associated with higher aqueous p-tau181 (p = 0.02). Aqueous p-tau181 and plasma p-tau181 were negatively associated with MoCA-BLIND scores (p = 0.005 and p = 0.001 respectively) in these patients. Conclusions: Aqueous p-tau181 is positively correlated with plasma p-tau181 and is negatively correlated with MoCA-BLIND scores. Further study in individuals with mild cognitive impairment or AD characterized by cerebrospinal fluid and volumetric MRI metrics may yield further insights.


Assuntos
Humor Aquoso , Cognição , Proteínas tau , Humanos , Proteínas tau/sangue , Proteínas tau/líquido cefalorraquidiano , Masculino , Feminino , Idoso , Fosforilação , Humor Aquoso/metabolismo , Pessoa de Meia-Idade , Cognição/fisiologia , Testes de Estado Mental e Demência , Idoso de 80 Anos ou mais , Biomarcadores/sangue
2.
JMIR Public Health Surveill ; 10: e51993, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922648

RESUMO

BACKGROUND: A challenge in achieving the malaria-elimination target in the Greater Mekong Subregion, including Thailand, is the predominance of Plasmodium vivax malaria, which has shown extreme resilience to control measures. OBJECTIVE: This proof-of-concept study aimed to provide evidence for implementing primaquine mass drug administration (pMDA) as a strategy for P. vivax elimination in low-endemicity settings. METHODS: The study employed a mixed-methods trial to thoroughly evaluate the effectiveness, safety, acceptability, and community engagement of pMDA. The quantitative part was designed as a 2-period cluster-crossover randomized controlled trial. The intervention was pMDA augmented to the national prevention and control standards with directly observed treatment (DOT) by village health volunteers. The qualitative part employed in-depth interviews and brainstorming discussions. The study involved 7 clusters in 2 districts of 2 southern provinces in Thailand with persistently low P. vivax transmission. In the quantitative part, 5 cross-sectional blood surveys were conducted in both the pMDA and control groups before and 3 months after pMDA. The effectiveness of pMDA was determined by comparing the proportions of P. vivax infections per 1000 population between the 2 groups, with a multilevel zero-inflated negative binomial model adjusted for cluster and time as covariates and the interaction. The safety data comprised adverse events after drug administration. Thematic content analysis was used to assess the acceptability and engagement of stakeholders. RESULTS: In the pre-pMDA period, the proportions of P. vivax infections in the pMDA (n=1536) and control (n=1577) groups were 13.0 (95% CI 8.2-20.4) and 12.0 (95% CI 7.5-19.1), respectively. At month 3 post-pMDA, these proportions in the pMDA (n=1430) and control (n=1420) groups were 8.4 (95% CI 4.6-15.1) and 5.6 (95% CI 2.6-11.5), respectively. No statistically significant differences were found between the groups. The number of malaria cases reduced in all clusters in both groups, and thus, the impact of pMDA was inconclusive. There were no major safety concerns. Acceptance among the study participants and public health care providers at local and national levels was high, and they believed that pMDA had boosted awareness in the community. CONCLUSIONS: pMDA was associated with high adherence, safety, and tolerability, but it may not significantly impact P. vivax transmission. As this was a proof-of-concept study, we decided not to scale up the intervention with larger clusters and samples. An alternative approach involving a targeted primaquine treatment strategy with primaquine and DOT is currently being implemented. We experienced success regarding effective health care workforces at point-of-care centers, effective collaborations in the community, and commitment from authorities at local and national levels. Our efforts boosted the acceptability of the malaria-elimination initiative. Community engagement is recommended to achieve elimination targets. TRIAL REGISTRATION: Thai Clinical Trials Registry TCTR20190806004; https://www.thaiclinicaltrials.org/show/TCTR20190806004.


Assuntos
Antimaláricos , Malária Vivax , Administração Massiva de Medicamentos , Primaquina , Humanos , Primaquina/uso terapêutico , Primaquina/administração & dosagem , Tailândia/epidemiologia , Administração Massiva de Medicamentos/métodos , Administração Massiva de Medicamentos/estatística & dados numéricos , Masculino , Feminino , Adulto , Adolescente , Malária Vivax/tratamento farmacológico , Antimaláricos/uso terapêutico , Antimaláricos/administração & dosagem , Pessoa de Meia-Idade , Adulto Jovem , Estudo de Prova de Conceito , Criança , Estudos Cross-Over , Estudos Transversais , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia
3.
ArXiv ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38915911

RESUMO

Concentrations of pathogen genomes measured in wastewater have recently become available as a new data source to use when modeling the spread of infectious diseases. One promising use for this data source is inference of the effective reproduction number, the average number of individuals a newly infected person will infect. We propose a model where new infections arrive according to a time-varying immigration rate which can be interpreted as an average number of secondary infections produced by one infectious individual per unit time. This model allows us to estimate the effective reproduction number from concentrations of pathogen genomes while avoiding difficult to verify assumptions about the dynamics of the susceptible population. As a byproduct of our primary goal, we also produce a new model for estimating the effective reproduction number from case data using the same framework. We test this modeling framework in an agent-based simulation study with a realistic data generating mechanism which accounts for the time-varying dynamics of pathogen shedding. Finally, we apply our new model to estimating the effective reproduction number of SARS-CoV-2 in Los Angeles, California, using pathogen RNA concentrations collected from a large wastewater treatment facility.

4.
JCO Precis Oncol ; 8: e2300362, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38865671

RESUMO

PURPOSE: There is significant interest in identifying complete responders to neoadjuvant chemotherapy (NAC) before radical cystectomy (RC) to potentially avoid removal of a pathologically benign bladder. However, clinical restaging after NAC is highly inaccurate. The objective of this study was to develop a next-generation sequencing-based molecular assay using urine to enhance clinical staging of patients with bladder cancer. METHODS: Urine samples from 20 and 44 patients with bladder cancer undergoing RC were prospectively collected for retrospective analysis for molecular correlate analysis from two clinical trials, respectively. The first cohort was used to benchmark the assay, and the second was used to determine the performance characteristics of the test as it correlates to responder status as measured by pathologic examination. RESULTS: First, to benchmark the assay, known mutations identified in the tissue (MT) of patients from the Accelerated Methotrexate, Vinblastine, Doxorubicin, Cisplatin trial (ClinicalTrials.gov identifier: NCT01611662, n = 16) and a cohort from University of California-San Francisco (n = 4) were cross referenced against mutation profiles from urine (MU). We then determined the correlation between MU persistence and residual disease in pre-RC urine samples from a second prospective clinical trial (The pT0 trial; ClinicalTrials.gov identifier: NCT02968732). Residual MU status correlated strongly with residual disease status (pT0 trial; n = 44; P = .0092) when MU from urine supernatant and urine pellet were assessed separately and analyzed in tandem. The sensitivity, specificity, PPV, and NPV were 91%, 50%, 86%, and 63% respectively, with an overall accuracy of 82% for this second cohort. CONCLUSION: MU are representative of MT and thus can be used to enhance clinical staging of urothelial carcinoma. Urine biopsy may be used as a reliable tool that can be further developed to identify complete response to NAC in anticipation of safe RC avoidance.


Assuntos
Biomarcadores Tumorais , Cistectomia , Estadiamento de Neoplasias , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/urina , Biópsia , Estudos Retrospectivos , Terapia Neoadjuvante
5.
J Clin Invest ; 134(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747290

RESUMO

BACKGROUNDPreclinical studies suggest that cholesterol accumulation leads to insulin resistance. We previously reported that alterations in a monocyte cholesterol metabolism transcriptional network (CMTN) - suggestive of cellular cholesterol accumulation - were cross-sectionally associated with obesity and type 2 diabetes (T2D). Here, we sought to determine whether the CMTN alterations independently predict incident prediabetes/T2D risk, and correlate with cellular cholesterol accumulation.METHODSMonocyte mRNA expression of 11 CMTN genes was quantified among 934 Multi-Ethnic Study of Atherosclerosis (MESA) participants free of prediabetes/T2D; cellular cholesterol was measured in a subset of 24 monocyte samples.RESULTSDuring a median 6-year follow-up, lower expression of 3 highly correlated LXR target genes - ABCG1 and ABCA1 (cholesterol efflux) and MYLIP (cholesterol uptake suppression) - and not other CMTN genes, was significantly associated with higher risk of incident prediabetes/T2D. Lower expression of the LXR target genes correlated with higher cellular cholesterol levels (e.g., 47% of variance in cellular total cholesterol explained by ABCG1 expression). Further, adding the LXR target genes to overweight/obesity and other known predictors significantly improved prediction of incident prediabetes/T2D.CONCLUSIONThese data suggest that the aberrant LXR/ABCG1-ABCA1-MYLIP pathway (LAAMP) is a major T2D risk factor and support a potential role for aberrant LAAMP and cellular cholesterol accumulation in diabetogenesis.FUNDINGThe MESA Epigenomics and Transcriptomics Studies were funded by NIH grants 1R01HL101250, 1RF1AG054474, R01HL126477, R01DK101921, and R01HL135009. This work was supported by funding from NIDDK R01DK103531 and NHLBI R01HL119962.


Assuntos
Colesterol , Diabetes Mellitus Tipo 2 , Receptores X do Fígado , Estado Pré-Diabético , Transdução de Sinais , Humanos , Estado Pré-Diabético/genética , Estado Pré-Diabético/metabolismo , Masculino , Feminino , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Pessoa de Meia-Idade , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Colesterol/metabolismo , Idoso , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Monócitos/metabolismo , Fatores de Risco , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Idoso de 80 Anos ou mais
7.
Malar J ; 23(1): 138, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720269

RESUMO

BACKGROUND: Artemisinin resistance in Plasmodium falciparum threatens global malaria elimination efforts. To contain and then eliminate artemisinin resistance in Eastern Myanmar a network of community-based malaria posts was instituted and targeted mass drug administration (MDA) with dihydroartemisinin-piperaquine (three rounds at monthly intervals) was conducted. The prevalence of artemisinin resistance during the elimination campaign (2013-2019) was characterized. METHODS: Throughout the six-year campaign Plasmodium falciparum positive blood samples from symptomatic patients and from cross-sectional surveys were genotyped for mutations in kelch-13-a molecular marker of artemisinin resistance. RESULT: The program resulted in near elimination of falciparum malaria. Of 5162 P. falciparum positive blood samples genotyped, 3281 (63.6%) had K13 mutations. The prevalence of K13 mutations was 73.9% in 2013 and 64.4% in 2019. Overall, there was a small but significant decline in the proportion of K13 mutants (p < 0.001). In the MDA villages there was no significant change in the K13 proportions before and after MDA. The distribution of different K13 mutations changed substantially; F446I and P441L mutations increased in both MDA and non-MDA villages, while most other K13 mutations decreased. The proportion of C580Y mutations fell from 9.2% (43/467) before MDA to 2.3% (19/813) after MDA (p < 0.001). Similar changes occurred in the 487 villages where MDA was not conducted. CONCLUSION: The malaria elimination program in Kayin state, eastern Myanmar, led to a substantial reduction in falciparum malaria. Despite the intense use of artemisinin-based combination therapies, both in treatment and MDA, this did not select for artemisinin resistance.


Assuntos
Antimaláricos , Artemisininas , Resistência a Medicamentos , Malária Falciparum , Plasmodium falciparum , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Mianmar , Malária Falciparum/parasitologia , Malária Falciparum/epidemiologia , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Resistência a Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Humanos , Estudos Transversais , Feminino , Masculino , Adolescente , Adulto , Administração Massiva de Medicamentos , Adulto Jovem , Mutação , Criança , Pré-Escolar , Pessoa de Meia-Idade , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Erradicação de Doenças/estatística & dados numéricos , Piperazinas
8.
Sci Adv ; 10(14): eadm7624, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578995

RESUMO

When strongly pumped at twice their resonant frequency, nonlinear resonators develop a high-amplitude intracavity field, a phenomenon known as parametric self-oscillations. The boundary over which this instability occurs can be extremely sharp and thereby presents an opportunity for realizing a detector. Here, we operate such a device based on a superconducting microwave resonator whose nonlinearity is engineered from kinetic inductance. The device indicates the absorption of low-power microwave wavepackets by transitioning to a self-oscillating state. Using calibrated pulses, we measure the detection efficiency to zeptojoule energy wavepackets. We then apply it to measurements of electron spin resonance, using an ensemble of 209Bi donors in silicon that are inductively coupled to the resonator. We achieve a latched readout of the spin signal with an amplitude that is five hundred times greater than the underlying spin echoes.

9.
J Alzheimers Dis ; 98(2): 593-600, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38393897

RESUMO

Background: Some human studies have identified infection with cytomegalovirus (CMV), a member of the alpha herpesvirus family, as a risk factor for Alzheimer's disease and related dementias (ADRD). To our knowledge, no studies have evaluated associations of CMV seropositivity with plasma biomarkers of ADRD risk in middle-aged adults. Objective: In participants recruited for an exercise study, we evaluated cross-sectional associations of CMV seropositivity with: Aß42/Aß40 ratio, a low ratio suggestive of central nervous system Aß accumulation; glial fibrillary acidic protein (GFAP), a measure of neuroinflammation; and neurofilament light (NfL), a measure of neurodegeneration. Methods: Anti-CMV IgG was quantified by ELISA. Plasma ADRD biomarkers were quantified using the ultrasensitive SIMOA assay. We used linear regression to evaluate associations of CMV seropositivity with the ADRD biomarkers, adjusting for age, sex, and race (n = 303; Age = 55.7±9.2 years). For ADRD biomarkers significantly associated with CMV seropositivity, we evaluated continuous associations of anti-CMV IgG levels with the ADRD biomarkers, excluding CMV seronegative participants. Results: 53% of participants were CMV seropositive. CMV seropositivity was associated with a lesser Aß42/Aß40 ratio (ß=-3.02e-03 95% CI [-5.97e-03, -7.18e-05]; p = 0.045). In CMV seropositive participants, greater anti-CMV IgG levels were associated with a lesser Aß42/Aß40 ratio (ß=-4.85e-05 95% CI[-8.45e-05, -1.25e-05]; p = 0.009). CMV seropositivity was not associated with plasma GFAP or NfL in adjusted analyses. Conclusions: CMV seropositivity was associated with a lesser plasma Aß42/Aß40 ratio. This association may be direct and causally related to CMV neuro-cytotoxicity or may be indirect and mediated by inflammatory factors resulting from CMV infection burden and/or the immune response.


Assuntos
Doença de Alzheimer , Infecções por Citomegalovirus , Humanos , Pessoa de Meia-Idade , Estudos Transversais , Peptídeos beta-Amiloides , Infecções por Citomegalovirus/complicações , Citomegalovirus , Imunoglobulina G , Biomarcadores , Anticorpos Antivirais , Proteínas tau
10.
Lancet Glob Health ; 11(12): e1955-e1963, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973343

RESUMO

BACKGROUND: Yemen continues to endure cholera outbreaks during ongoing conflict and destructive environmental events. Air raids have been used throughout the conflict to target military and civilian infrastructure. We aimed to assess the association between air raids and cholera incidence while taking into account geographical, environmental, economic, and demographic factors that drive outbreaks. METHODS: In this ecological modelling study, we used data from Sept 12, 2016, to Dec 29, 2019, for the number of air raids, vegetation coverage, surface water, precipitation, temperature, economic variables, and cholera case and population data to model the association between conflict and the weekly incidence of cholera (per 100 000 people) in Yemen. Data were transformed into weekly intervals and governorates were categorised according to air raid severity (the number of raids in the previous 3 months). We used a negative binomial generalised additive model that accounted for geographical location and environmental, temporal, economic, and demographic variables to estimate incidence rate ratios for the association between air raid severity and cases of cholera. FINDINGS: During the study period, 2 107 912 cases of cholera were reported in Yemen, and a minimum of 11 366 air raids were recorded. After controlling for relevant factors, compared with no air raids, all other levels of air raid severity were significantly associated with cholera incidence. The largest effect was noted in governorates with severe air raid levels (ie, ≥76 during the previous 3 months), which had an incidence rate ratio of 2·06 (95% CI 1·59-2·69; p<0·0001) for cholera compared with governorates with no air raids in the previous 3 months. Economic factors were also significantly associated with increased cholera incidence. INTERPRETATION: Air raids were significantly associated with the burden of cholera in Yemen, even after controlling for other relevant factors. Quantification of this relationship further shows that the cholera outbreak is largely a result of human action rather than a natural occurrence, and demonstrates the conflict's devastating effects on health. Our findings highlight the need for ceasefire and peacebuilding efforts, as well as infrastructure and economic restoration, to reduce Yemen's cholera burden. FUNDING: None. TRANSLATION: For the Arabic translation of the abstract see Supplementary Materials section.


Assuntos
Cólera , Humanos , Cólera/epidemiologia , Iêmen/epidemiologia , Incidência , Surtos de Doenças , Modelos Teóricos
11.
Phys Rev Lett ; 131(13): 136502, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37832017

RESUMO

The pursuit of exotic phases of matter outside of the extreme conditions of a quantizing magnetic field is a long-standing quest of solid state physics. Recent experiments have observed spontaneous valley polarization and fractional Chern insulators in zero magnetic field in twisted bilayers of MoTe_{2}, at partial filling of the topological valence band (ν=-2/3 and -3/5). We study the topological valence band at half filling, using exact diagonalization and density matrix renormalization group calculations. We discover a composite Fermi liquid (CFL) phase even at zero magnetic field that covers a large portion of the phase diagram near twist angle ∼3.6°. The CFL is a non-Fermi liquid phase with metallic behavior despite the absence of Landau quasiparticles. We discuss experimental implications including the competition between the CFL and a Fermi liquid, which can be tuned with a displacement field. The topological valence band has excellent quantum geometry over a wide range of twist angles and a small bandwidth that is, remarkably, reduced by interactions. These key properties stabilize the exotic zero field quantum Hall phases. Finally, we present an optical signature involving "extinguished" optical responses that detects Chern bands with ideal quantum geometry.

12.
J Wound Care ; 32(9): 587-596, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37682784

RESUMO

OBJECTIVE: To investigate reliability and changes of in-shoe plantar pressure and shear during walking at three cadences with two insole designs. This was a precursor to the investigation of plantar loading in people with diabetes for potential foot ulcer prevention. METHOD: A sensorised insole system, capable of measuring plantar pressure and shear at the heel, fifth metatarsal head (5MH), first metatarsal head (1MH) and hallux, was tested with ten healthy participants during level walking. Reliability was evaluated, using intra-class correlation coefficient (ICC), while varying the cadences and insole types. Percentage changes in pressure and shear relative to values obtained at self-selected cadence with a flat insole design were investigated. RESULTS: Mean±standard deviation of maximum pressure, medial-lateral and anterior-posterior shear of up to 380±24kPa, 46±2kPa and -71±4kPa, respectively, were measured. The ICC in ranges of 0.762-0.973, 0.758-0.987 and 0.800-0.980 were obtained for pressure, anterior-posterior and medial-lateral shear, respectively. Opposite anterior-posterior shear directions between 5MH and 1MH (stretching), and between 1MH and hallux (pinching) were observed for some participants. Increasing cadence increased pressure and anterior-posterior shear (by up to +77%) but reduced medial-lateral shear at the heel and hallux (by up to -34%). Slower cadence increased anterior-posterior shear (+114%) but decreased medial-lateral shear (-46%) at the hallux. The use of a flexible contoured insole resulted in pressure reduction at the heel and 5MH but an increase in anterior-posterior shear at the heel (+69%) and hallux (+75%). CONCLUSION: The insole system demonstrated good reliability and is comparable to reported pressure-only systems. Pressure measurements were sensitive to changes in cadence and insole designs in ways that were consistent with the literature. However, our plantar shear showed localised shear changes with cadences and insoles for the first time, as well as stretching and pinching effects on plantar tissue. This opens new possibilities to investigate plantar tissue viability, loading characteristics and orthotic designs aimed towards foot ulcer prevention.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/prevenção & controle , Reprodutibilidade dos Testes , Sapatos , Voluntários Saudáveis , Caminhada
13.
ArXiv ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37693183

RESUMO

Concentrations of pathogen genomes measured in wastewater have recently become available as a new data source to use when modeling the spread of infectious diseases. One promising use for this data source is inference of the effective reproduction number, the average number of individuals a newly infected person will infect. We propose a model where new infections arrive according to a time-varying immigration rate which can be interpreted as a compound parameter equal to the product of the proportion of susceptibles in the population and the transmission rate. This model allows us to estimate the effective reproduction number from concentrations of pathogen genomes while avoiding difficult to verify assumptions about the dynamics of the susceptible population. As a byproduct of our primary goal, we also produce a new model for estimating the effective reproduction number from case data using the same framework. We test this modeling framework in an agent-based simulation study with a realistic data generating mechanism which accounts for the time-varying dynamics of pathogen shedding. Finally, we apply our new model to estimating the effective reproduction number of SARS-CoV-2 in Los Angeles, California, using pathogen RNA concentrations collected from a large wastewater treatment facility.

14.
Front Genet ; 14: 1236509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719713

RESUMO

Dysregulation of physiological processes may contribute to Alzheimer's disease (AD) development. We previously found that an increase in the level of physiological dysregulation (PD) in the aging body is associated with declining resilience and robustness to major diseases. Also, our genome-wide association study found that genes associated with the age-related increase in PD frequently represented pathways implicated in axon guidance and synaptic function, which in turn were linked to AD and related traits (e.g., amyloid, tau, neurodegeneration) in the literature. Here, we tested the hypothesis that genes involved in PD and axon guidance/synapse function may jointly influence onset of AD. We assessed the impact of interactions between SNPs in such genes on AD onset in the Long Life Family Study and sought to replicate the findings in the Health and Retirement Study. We found significant interactions between SNPs in the UNC5C and CNTN6, and PLXNA4 and EPHB2 genes that influenced AD onset in both datasets. Associations with individual SNPs were not statistically significant. Our findings, thus, support a major role of genetic interactions in the heterogeneity of AD and suggest the joint contribution of genes involved in PD and axon guidance/synapse function (essential for the maintenance of complex neural networks) to AD development.

15.
Phys Rev Lett ; 131(9): 096401, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721816

RESUMO

Moiré systems have emerged in recent years as a rich platform to study strong correlations. Here, we will propose a simple, experimentally feasible setup based on periodically strained graphene that reproduces several key aspects of twisted moiré heterostructures-but without introducing a twist. We consider a monolayer graphene sheet subject to a C_{2}-breaking periodic strain-induced pseudomagnetic field with period L_{M}≫a, along with a scalar potential of the same period. This system has almost ideal flat bands with valley-resolved Chern number ±1, where the deviation from ideal band geometry is analytically controlled and exponentially small in the dimensionless ratio (L_{M}/l_{B})^{2}, where l_{B} is the magnetic length corresponding to the maximum value of the pseudomagnetic field. Moreover, the scalar potential can tune the bandwidth far below the Coulomb scale, making this a very promising platform for strongly interacting topological phases. Using a combination of strong-coupling theory and self-consistent Hartree-Fock, we find quantum anomalous Hall states at integer fillings. At fractional filling, exact diagonaliztion reveals a fractional Chern insulator at parameters in the experimentally feasible range. Overall, we find that this system has larger interaction-induced gaps, smaller quasiparticle dispersion, and enhanced tunability compared to twisted graphene systems, even in their ideal limit.

16.
PLOS Glob Public Health ; 3(7): e0002200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494337

RESUMO

Mass drug administration (MDA) with antimalarials has been shown to reduce prevalence and interrupt transmission in small populations, in populations with reliable access to antimalarial drugs, and in populations where sustained improvements in diagnosis and treatment are possible. In addition, when MDA is effective it eliminates both drug-resistant parasites and drug-sensitive parasites, which has the long-term benefit of extending the useful therapeutic life of first-line therapies for all populations, not just the focal population where MDA was carried out. However, in order to plan elimination measures effectively, it is necessary to characterize the conditions under which failed MDA could exacerbate resistance. We use an individual-based stochastic model of Plasmodium falciparum transmission to evaluate this risk for MDA using dihydroartemisinin-piperaquine (DHA-PPQ), in populations where access to antimalarial treatments may not be uniformly high and where re-importation of drug-resistant parasites may be common. We find that artemisinin-resistance evolution at the kelch13 locus can be accelerated by MDA when all three of the following conditions are met: (1) strong genetic bottlenecking that falls short of elimination, (2) re-importation of artemisinin-resistant genotypes, and (3) continued selection pressure during routine case management post-MDA. Accelerated resistance levels are not immediate but follow the rebound of malaria cases post-MDA, if this is allowed to occur. Crucially, resistance is driven by the selection pressure during routine case management post-MDA and not the selection pressure exerted during the MDA itself. Second, we find that increasing treatment coverage post-MDA increases the probability of local elimination in low-transmission regions (prevalence < 2%) in scenarios with both low and high levels of drug-resistance importation. This emphasizes the importance of planning for and supporting high coverage of diagnosis and treatment post-MDA.

17.
J Inorg Biochem ; 245: 112240, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37245283

RESUMO

A one-pot chemoenzymatic approach was developed by combining Palladium-catalysis with selective cytochrome P450 enzyme oxyfunctionalization. Various iodophenyl alkanoic acids could be coupled with alkylphenyl boronic acids to generate a series of alkyl substituted biarylalkanoic acids in overall high yield. The identity of the products could be confirmed by various analytical and chromatographic techniques. Addition of an engineered cytochrome P450 heme domain mutant with peroxygenase activity upon completion of the chemical reaction resulted in the selective oxyfunctionalization of those compounds, primarily at the benzylic position. Moreover, in order to increase the biocatalytic product conversion, a reversible substrate engineering approach was developed. This involves the coupling of a bulky amino acid such as L- phenylalanine or tryptophan, to the carboxylic acid moiety. The approach resulted in a 14 to 49% overall biocatalytic product conversion increase associated with a change in regioselectivity of hydroxylation towards less favored positions.


Assuntos
Sistema Enzimático do Citocromo P-450 , Domínio Catalítico , Sistema Enzimático do Citocromo P-450/metabolismo , Biocatálise , Hidroxilação , Catálise , Especificidade por Substrato
18.
Sci Rep ; 13(1): 5963, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045879

RESUMO

Targeted mass primaquine treatment (TPT) might be an effective intervention to facilitate elimination of vivax malaria in Myanmar by 2030. In this study, we explored the factors hindering coverage of a TPT campaign conducted in a malarious township of northern Myanmar. From August 2019 to July 2020, a cross-sectional exploratory design including quantitative and qualitative data was conducted in five villages with high P. vivax prevalence following a TPT campaign. Among a targeted population of 2322; 1973 (85.0%) participated in the baseline mass blood survey (MBS) and only 52.0% of the total targeted population (1208, 91.9% of total eligible population) completed the TPT. G6PD deficiency was found among 13.5% of total MBS participants and those were excluded from TPT. Of 1315 eligible samples, farmers and gold miners, males, and those aged 15 to 45 years had higher percentages of non-participation in TPT. Qualitative findings showed that most of the non-participation groups were outside the villages during TPT because of time-sensitive agricultural and other occupational or education-related purposes. In addition to mitigating of some inclusion criteria (i.e. including young children or offering weekly PQ treatment to G6PD deficient individuals), strengthening community awareness and increasing engagement should be pursued to increase community participation.


Assuntos
Antimaláricos , Deficiência de Glucosefosfato Desidrogenase , Malária Vivax , Masculino , Criança , Humanos , Pré-Escolar , Primaquina/uso terapêutico , Antimaláricos/uso terapêutico , Estudos Transversais , Mianmar/epidemiologia , Malária Vivax/tratamento farmacológico , Malária Vivax/epidemiologia
19.
Int J Audiol ; : 1-11, 2023 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37005863

RESUMO

OBJECTIVE: The purpose of this study was to investigate whether focusing on positive listening experiences improves hearing aid outcomes in experienced hearing aid users. DESIGN: The participants were randomised into a control or positive focus (PF) group. At the first laboratory visit, the Client-Oriented Scale of Improvement (COSI) questionnaire was administered followed by hearing aid fitting. The participants wore the hearing aids for three weeks. The PF group was asked to report their positive listening experiences via an app. During the third week, all the participants answered questionnaires related to hearing aid benefit and satisfaction. This was followed by the second laboratory visit where the COSI follow-up questionnaire was administered. STUDY SAMPLE: Ten participants were included in the control and eleven in the PF group. RESULTS: Hearing aid outcome ratings were significantly better in the PF group in comparison to the control group. Further, COSI degree of change and the number of positive reports were positively correlated. CONCLUSIONS: These results point to the importance of asking hearing aid users to focus on positive listening experiences and talk about them. The potential outcome is increased hearing aid benefit and satisfaction which could lead to more consistent use of the devices.

20.
Emerg Infect Dis ; 29(5): 977-987, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37081530

RESUMO

Combining genomic and geospatial data can be useful for understanding Mycobacterium tuberculosis transmission in high-burden tuberculosis (TB) settings. We performed whole-genome sequencing on M. tuberculosis DNA extracted from sputum cultures from a population-based TB study conducted in Gaborone, Botswana, during 2012-2016. We determined spatial distribution of cases on the basis of shared genotypes among isolates. We considered clusters of isolates with ≤5 single-nucleotide polymorphisms identified by whole-genome sequencing to indicate recent transmission and clusters of ≥10 persons to be outbreaks. We obtained both molecular and geospatial data for 946/1,449 (65%) participants with culture-confirmed TB; 62 persons belonged to 5 outbreaks of 10-19 persons each. We detected geospatial clustering in just 2 of those 5 outbreaks, suggesting heterogeneous spatial patterns. Our findings indicate that targeted interventions applied in smaller geographic areas of high-burden TB identified using integrated genomic and geospatial data might help interrupt TB transmission during outbreaks.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Botsuana/epidemiologia , Tuberculose/microbiologia , Mycobacterium tuberculosis/genética , Genótipo , Genômica
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