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1.
Leuk Res ; 142: 107504, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38703634

RESUMO

INTRODUCTION: This longitudinal study was based on the outcomes of Donor Lymphocyte Infusion (DLI) for falling peripheral blood (PB) CD34+ and CD3+ donor chimerism (DC). METHODS: From 2012 to 2018, data was collected from the BMT database and electronic medical records (EMR). The primary objective was to compare the indication for DLI based on falling PB CD34+ or CD3+ DC in patients post allo-SCT for AML and MDS and their overall survival (OS). RESULTS: 18/70 patients met the inclusion criteria. Indications for DLI were i) falling PB CD34+ DC ≤ 80 % with morphological relapse, ii) falling PB CD34+ DC ≤ 80 % without morphological relapse and iii) falling PB CD3+ DC ≤ 80 % without falling PB CD34+ DC. Log rank analysis showed falling PB CD34+ DC and morphological relapse had significantly lower OS. Linear regression demonstrated better OS post DLI if there was PB CD34+ and CD3+ chimerism response at 30 days (p = 0.029), GVHD (p = 0.032) and tapering immunosuppression at the time of falling DC (p = 0.042). CONCLUSION: DLI for PB CD34+ DC values ≤ 80 % and morphological relapse had the lowest OS. In this study, full DC was achieved after DLI even with a PB CD3+DC value as low as 13 %, provided the PB CD34+ DC remained > 80 %. Further research is vital in CD34+ DC as a biomarker for disease relapse and loss of engraftment.

2.
J Hum Genet ; 69(6): 255-262, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38454133

RESUMO

A previous study of 200,000 exome-sequenced UK Biobank participants investigating the association between rare coding variants and hyperlipidaemia had implicated four genes, LDLR, PCSK9, APOC3 and IFITM5, at exome-wide significance. In addition, a further 43 protein-coding genes were significant with an uncorrected p value of <0.001. Exome sequence data has become available for a further 270,000 participants and weighted burden analysis to test for association with hyperlipidaemia was carried out in this sample for the 47 genes highlighted by the previous study. There was no evidence to implicate IFITM5 but LDLR, PCSK9, APOC3, ANGPTL3, ABCG5 and NPC1L1 were all statistically significant after correction for multiple testing. These six genes were also all exome-wide significant in the combined sample of 470,000 participants. Variants impairing function of LDLR and ABCG5 were associated with increased risk whereas variants in the other genes were protective. Variant categories associated with large effect sizes are cumulatively very rare and the main benefit of this kind of study seems to be to throw light on the molecular mechanisms impacting hyperlipidaemia risk, hopefully supporting attempts to develop improved therapies.


Assuntos
Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Bancos de Espécimes Biológicos , Sequenciamento do Exoma , Predisposição Genética para Doença , Hiperlipidemias , Receptores de LDL , Humanos , Hiperlipidemias/genética , Reino Unido/epidemiologia , Receptores de LDL/genética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Pró-Proteína Convertase 9/genética , Exoma/genética , Variação Genética , Proteína 3 Semelhante a Angiopoietina , Feminino , Masculino , Biobanco do Reino Unido , Lipoproteínas , Apolipoproteína C-III
4.
Leukemia ; 38(5): 951-962, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38553571

RESUMO

Relapse in T-cell acute lymphoblastic leukemia (T-ALL) may signify the persistence of leukemia-initiating cells (L-ICs). Ectopic TAL1/LMO expression defines the largest subset of T-ALL, but its role in leukemic transformation and its impact on relapse-driving L-ICs remain poorly understood. In TAL1/LMO mouse models, double negative-3 (DN3; CD4-CD8-CD25+CD44-) thymic progenitors harbored L-ICs. However, only a subset of DN3 leukemic cells exhibited L-IC activity, and studies linking L-ICs and chemotolerance are needed. To investigate L-IC heterogeneity, we used mouse models and applied single-cell RNA-sequencing and nucleosome labeling techniques in vivo. We identified a DN3 subpopulation with a cell cycle-restricted profile and heightened TAL1/LMO2 activity, that expressed genes associated with stemness and quiescence. This dormant DN3 subset progressively expanded throughout leukemogenesis, displaying intrinsic chemotolerance and enrichment in genes linked to minimal residual disease. Examination of TAL/LMO patient samples revealed a similar pattern in CD7+CD1a- thymic progenitors, previously recognized for their L-IC activity, demonstrating cell cycle restriction and chemotolerance. Our findings substantiate the emergence of dormant, chemotolerant L-ICs during leukemogenesis, and demonstrate that Tal1 and Lmo2 cooperate to promote DN3 quiescence during the transformation process. This study provides a deeper understanding of TAL1/LMO-induced T-ALL and its clinical implications in therapy failure.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas com Domínio LIM , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Animais , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T/metabolismo , Proteína 1 de Leucemia Linfocítica Aguda de Células T/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas com Domínio LIM/metabolismo , Proteínas com Domínio LIM/genética , Timo/metabolismo , Timo/patologia , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia
5.
Contemp Clin Trials Commun ; 38: 101272, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38444876

RESUMO

Background: Digital health studies using electronic patient reported outcomes (ePROs), wearables, and clinical data to provide a more comprehensive picture of patient health. Methods: Newly initiated patients on upadacitinib or adalimumab for RA will be recruited from community settings in the Excellence NEtwork in RheumatoloGY (ENRGY) practice-based research network. Over the period of three to six months, three streams of data will be collected (1) linkable physician-derived data; (2) self-reported daily and weekly ePROs through the ArthritisPower registry app; and (3) biometric sensor data passively collected via wearable. These data will be analyzed to evaluate correlations among the three types of data and patient improvement on the newly initiated medication. Conclusions: Results from this study will provide valuable information regarding the relationships between physician data, wearable data, and ePROs in patients newly initiating an RA treatment, and demonstrate the feasibility of digital data capture for Remote Patient Monitoring of patients with rheumatic disease.

6.
Hum Hered ; 89(1): 1-7, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342085

RESUMO

INTRODUCTION: Previous studies have demonstrated effects of rare coding variants on common, clinically relevant phenotypes although the additive burden of these variants makes only a small contribution to overall trait variance. Although recessive effects of individual homozygous variants have been studied, little work has been done to elucidate the impact of rare coding variants occurring together as compound heterozygotes. METHODS: In this study, attempts were made to identify pairs of variants likely to be occurring as compound heterozygotes using 200,000 exome-sequenced subjects from the UK Biobank. Pairs of variants, which were seen together in the same subject more often than would be expected by chance, were excluded as it was assumed that these might be present in the same haplotype. Attention was restricted to variants with minor allele frequency ≤0.05 and to those predicted to alter amino acid sequence or prevent normal gene expression. For each gene, compound heterozygotes were assigned scores based on the rarity and predicted functional consequences of the constituent variants and the scores were used in a logistic regression analysis to test for association with hypertension, hyperlipidaemia, and type 2 diabetes. RESULTS: No statistically significant associations were observed and the results conformed to the distribution, which would be expected under the null hypothesis. The average number of apparently compound heterozygous subjects for each gene was only 282.2. CONCLUSION: It seems difficult to detect an effect of compound heterozygotes on the risk of these phenotypes. Even if recessive effects from compound heterozygotes do occur, they would only affect a small number of people and overall would not make a substantial contribution to phenotypic variance. This research has been conducted using the UK Biobank Resource.


Assuntos
Exoma , Fenótipo , Feminino , Humanos , Masculino , Diabetes Mellitus Tipo 2/genética , Exoma/genética , Sequenciamento do Exoma/métodos , Frequência do Gene/genética , Genes Recessivos , Predisposição Genética para Doença , Variação Genética , Heterozigoto , Biobanco do Reino Unido , Reino Unido
7.
Pulse (Basel) ; 12(1): 19-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404912

RESUMO

Background: Genetic variants causing diseases with hypertension as a secondary feature have previously been identified. Studies focussing on primary hypertension have utilised common and latterly rare genetic variants in attempts to elucidate the genetic contribution to the risk of primary hypertension. Summary: Using genome-wide association studies (GWASs), associations of hypertension with hundreds of common genetic variants have been reported, implicating thousands of genes. Individual variants have small effect sizes and cumulatively account for around 6% of genetic risk. The common variant signal is enriched for relevant tissues and physiological processes, while some variants are associated with traits expected to have secondary impacts on hypertension risk, such as fruit intake, BMI, or time watching television. Studies using rare variants obtained from exome sequence data have implicated a small number of genes for which impaired function has moderate effects on blood pressure and/or hypertension risk. Notably, genetic variants which impair elements of guanylate cyclase activation, stimulated by either natriuretic hormones or nitric oxide, increase hypertension risk. Conversely, variants impairing dopamine beta-hydroxylase or renin production are associated with lower blood pressure. Variants for which a definite effect can be designated remain cumulatively extremely rare and again make only a small contribution to overall genetic risk. Although these results are of interest, it is not clear that they provide radical new insights or identify drug targets which were not previously known. Nor does it seem that genetic testing could be useful in terms of quantifying disease risk or guiding treatment. Key Messages: Research has increased our knowledge about the relationship between naturally occurring genetic variation and risk of hypertension. Although some results serve to confirm our understanding of underlying physiology, their value in terms of potentially leading to practical advances in the management of hypertension appears questionable.

8.
Health Place ; 85: 103177, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241851

RESUMO

We develop county-level measures of structural and institutional barriers to care, and test associations between these barriers and birth outcomes for US-born Black and White mothers using national birth records for 2014-2017. Results indicate elevated odds of greater preterm birth severity for Black mothers in counties with higher uninsurance rates among Black adults, fewer Black physicians per Black residents, and fewer publicly-funded contraceptive services. Most structural barriers were not associated with small-for-gestational-age birth, and barriers defined for Black residents were not associated with birth outcomes for White mothers, with the exception of Black uninsurance rate. Structural determinants of care may influence preterm birth risk for Black Americans.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Nascimento Prematuro , Adulto , Feminino , Humanos , Recém-Nascido , Atenção à Saúde , Nascimento Prematuro/epidemiologia , Fatores de Risco , Brancos , Negro ou Afro-Americano , Pessoas sem Cobertura de Seguro de Saúde
9.
Urology ; 183: 163-169, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38167595

RESUMO

OBJECTIVES: To compare the detection rate of clinically significant prostate cancer (csPC) and prostate cancer (PC) and to find out the diagnostic concordance between microultrasound (mUS), a high-resolution imaging system that can identify suspicious prostate lesions and biopsy them in real time, and multiparametric magnetic resonance imaging (mpMRI)-guided prostate fusion biopsies. METHODS: A prospective, multicenter, single-blind, single cohort study was conducted involving 80 patients with clinically suspected PC who underwent concomitant mpMRI-guided fusion prostate biopsy (Koelis System) and mUS-guided biopsy (ExactVu System) RESULTS: The detection rate of csPC was slightly higher for image-guided fusion biopsy (21.25% vs 18.75%), but this difference was not statistically significant (P = .453). There was also no significant difference in overall PC diagnosis (50% vs 51.25%, P = .897). The degree of agreement between the 2 diagnostic techniques for the detection of csPC as assessed by Cohen's Kappa concordance index was satisfactory κ ̂ = 0.676. The degree of International Society of Urological Pathology of targeted biopsies obtained from concordant lesions was also represented by satisfactory concordance with a Kappa index of κ ̂ = 0. 696. CONCLUSION: mUS-guided biopsy is presented as an effective diagnostic method for the diagnosis of csPC compared to image-guided fusion biopsy. No differences are found in the detection rates of csPC and PC between the 2 strategies and satisfactory concordance is found in terms of histopathological findings.


Assuntos
Próstata , Neoplasias da Próstata , Humanos , Masculino , Biópsia , Estudos de Coortes , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Método Simples-Cego
10.
J Prim Care Community Health ; 15: 21501319241226766, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38270076

RESUMO

OBJECTIVE: To describe blood pressure and glycemic control by racial/ethnic group in the US Community Health Center (CHC) patient population, and whether center characteristics, proxying for higher resource levels and better quality of care, were associated with greater rates of controlled cardiometabolic conditions. METHODS: Data came from the Uniform Data System, representing aggregate patient clinical data for individual health centers in 2019. Descriptive analyses were conducted weighting by health center patient populations to produce race-specific national rates of blood pressure and glycemic control, and linear regression is used to test whether cardiometabolic control rates varied by center characteristics. RESULTS: Hypertension was controlled for 67.2% of non-Hispanic White, 66.9% of Hispanic, and 56.7% of non-Hispanic Black patients. Diabetes was controlled for 70.7% of non-Hispanic White, 65.7% of Hispanic, and 66.1% of non-Hispanic Black patients. The rate of blood pressure control was 2.54 to 3.99 percentage points higher across racial/ethnic groups in health centers that adopted a patient-centered medical home (PCMH) model of care relative to non-PCMH centers, while glycemic control was 1.08 to 2.27 pp. higher as a function of PCMH certification. Results for other center characteristics did not show consistent patterns across racial groups or outcomes. CONCLUSION: This study documented racial and ethnic health disparities in the CHC patient population after major expansion of the CHC program. CHCs with PCMH certification have improved clinical outcomes among patients with hypertension and diabetes across racial/ethnic groups relative to centers without this certification.


Assuntos
Diabetes Mellitus , Hipertensão , Humanos , Pressão Sanguínea , Controle Glicêmico , Centros Comunitários de Saúde , Hipertensão/epidemiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia
13.
Transplant Cell Ther ; 30(3): 334.e1-334.e7, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38029962

RESUMO

There is a limited body of evidence for haploidentical hematopoietic stem cell transplantation (haplo-HSCT) in older patients. Previous studies have used a high proportion of bone marrow-derived grafts and a variety of conditioning regimens. In Australia and New Zealand, haplo-HCST is predominantly performed using peripheral blood (PB) with universal use of post-transplantation cyclophosphamide (PTCy). To characterize the outcomes of older recipients undergoing haplo-HSCT for acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Data were collected through the Australasian Bone Marrow Transplant Recipient Registry (ABMTRR) for patients aged 65 or older receiving a PB haplo-HSCT for AML/MDS between January 2010 and July 2020. A total of 44 patients were included in the analysis. The median follow-up time was 377 days. The median age was 68 (range 65-74) with a median Karnofsky performance status of 90. Thirty patients (68.2%) had AML, whereas 14 (31.8%) had MDS. The median donor age was 40. The most common conditioning regimen was nonmyeloablative fludarabine, cyclophosphamide, and total body irradiation (75%); the remainder of the patients received either melphalan- or busulfan-based regimens, and the majority were reduced intensity, with only 2 patients undergoing myeloablative conditioning. All patients received post-transplantation cyclophosphamide and mycophenolate mofetil, with the majority also receiving tacrolimus (90.5%) and the remainder receiving cyclosporine (9.5%). No patients received anti-thymocyte globulin. Neutrophil engraftment was achieved in 97.6% of patients at a median of 18 days, whereas platelet engraftment was achieved in 92.7% of patients at a median of 28 days. The cumulative incidences of cytomegalovirus (CMV) reactivation and CMV disease were 52.5% and 5.1% at 1 year. The incidence of grade 2-4 acute Graft Versus Host Disease (GVHD) was 18.2%. The incidence of chronic GVHD at 2 years was 40.7%, with extensive chronic GVHD occurring in 17.7% of patients. The incidences of relapse and non-relapse mortality (NRM) at 2 years were 8.8% and 20.7% respectively. The leading causes of death were infection (64.7%) followed by relapse (14.2%). The 2-year overall survival was 74%. Relapse free survival and GVHD free, relapse free survival at 2 years was 70% and 48%. Haplo-HSCT using a peripheral blood graft and PTCy GVHD prophylaxis demonstrates long-term disease control with acceptable rates of NRM for older patients with AML/MDS.


Assuntos
Infecções por Citomegalovirus , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Transplante de Células-Tronco de Sangue Periférico , Humanos , Idoso , Nova Zelândia/epidemiologia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Ciclofosfamida/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Síndromes Mielodisplásicas/terapia , Recidiva
14.
Cities ; 1452024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38075593

RESUMO

Socially disadvantaged groups generally are more likely to reside in areas with less desirable conditions. We examined longitudinal relationships between neighborhood resident characteristics and amenities from 1990 to 2010 in an urban area of Utah, U.S. Four temporal patterns of social inequities are described using mixed-effects models: historical inequities; differential selection into amenity-rich tracts; differential investment in amenities; and simultaneous twenty-year change. Results indicate historical differences by neighborhood socioeconomic status, with lower status tracts having fewer green/natural amenities and higher air pollution in 1990 but also greater walkability and more food stores. Differences in amenities by neighborhood socioeconomic status widened over time as aggregate socioeconomic status disproportionately increased in tracts with more green/natural amenities, less air pollution, and lower walkability in 1990, consistent with differential selection. Tract percentage non-Hispanic White did not predict historical differences, but tracts that were less walkable and had fewer healthy food stores in 1990 experienced larger subsequent increases in racial/ethnic diversity. Tracts with higher relative to lower percentage non-Hispanic White in 1990 had larger decreases in air pollution but declining green/natural amenities. This study shows how social inequities in neighborhood amenities change over time, providing evidence of historical socioeconomic differences increasing from differential resident selection.

15.
Pulse (Basel) ; 11(1): 9-16, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38090255

RESUMO

Introduction: A previous study of 200,000 exome-sequenced UK Biobank participants to test for association of rare coding variants with hypertension implicated two genes at exome-wide significance, DNMT3A and FES. A total of 42 genes had an uncorrected p value <0.001. These results were followed up in a larger sample of 470,000 exome-sequenced participants. Methods: Weighted burden analysis of rare coding variants in a new sample of 97,050 cases and 172,263 controls was carried out for these 42 genes. Those showing evidence for association were then analysed in the combined sample of 167,127 cases and 302,691 controls. Results: The association of DNMT3A and FES with hypertension was replicated in the new sample and they and the previously implicated gene NPR1, which codes for a membrane-bound guanylate cyclase, were all exome-wide significant in the combined sample. Also exome-wide significant as risk genes for hypertension were GUCY1A1, ASXL1, and SMAD6, while GUCY1B1 had a nominal p value of <0.0001. GUCY1A1 and GUCY1B1 code for subunits of a soluble guanylate cyclase. For two genes, DBH, which codes for dopamine beta hydroxylase, and INPPL1, rare coding variants predicted to impair gene function were protective against hypertension, again with exome-wide significance. Conclusion: The findings offer new insights into biological risk factors for hypertension which could be the subject of further investigation. In particular, genetic variants predicted to impair the function of either membrane-bound guanylate cyclase, activated by natriuretic peptides, or soluble guanylate cyclase, activated by nitric oxide, increase risk of hypertension. Conversely, variants impairing the function of dopamine beta hydroxylase, responsible for the synthesis of norepinephrine, reduce hypertension risk.

17.
JMIR Hum Factors ; 10: e44034, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37934559

RESUMO

BACKGROUND: Digital health studies using electronic patient-reported outcomes (ePROs) and wearables bring new challenges, including the need for participants to consistently provide trial data. OBJECTIVE: This study aims to characterize the engagement, protocol adherence, and data completeness among participants with rheumatoid arthritis enrolled in the Digital Tracking of Arthritis Longitudinally (DIGITAL) study. METHODS: Participants were invited to participate in this app-based study, which included a 14-day run-in and an 84-day main study. In the run-in period, data were collected via the ArthritisPower mobile app to increase app familiarity and identify the individuals who were motivated to participate. Successful completers of the run-in period were mailed a wearable smartwatch, and automated and manual prompts were sent to participants, reminding them to complete app input or regularly wear and synchronize devices, respectively, during the main study. Study coordinators monitored participant data and contacted participants via email, SMS text messaging, and phone to resolve adherence issues per a priori rules, in which consecutive spans of missing data triggered participant contact. Adherence to data collection during the main study period was defined as providing requested data for >70% of 84 days (daily ePRO, ≥80% daily smartwatch data) or at least 9 of 12 weeks (weekly ePRO). RESULTS: Of the 470 participants expressing initial interest, 278 (59.1%) completed the run-in period and qualified for the main study. Over the 12-week main study period, 87.4% (243/278) of participants met the definition of adherence to protocol-specified data collection for weekly ePRO, and 57.2% (159/278) did so for daily ePRO. For smartwatch data, 81.7% (227/278) of the participants adhered to the protocol-specified data collection. In total, 52.9% (147/278) of the participants met composite adherence. CONCLUSIONS: Compared with other digital health rheumatoid arthritis studies, a short run-in period appears useful for identifying participants likely to engage in a study that collects data via a mobile app and wearables and gives participants time to acclimate to study requirements. Automated or manual prompts (ie, "It's time to sync your smartwatch") may be necessary to optimize adherence. Adherence varies by data collection type (eg, ePRO vs smartwatch data). INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/14665.


Assuntos
Artrite Reumatoide , Aplicativos Móveis , Humanos , Coleta de Dados , Correio Eletrônico , Medidas de Resultados Relatados pelo Paciente
18.
Infect Immun ; 91(11): e0033223, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37877711

RESUMO

Many AB toxins contain an enzymatic A moiety that is anchored to a cell-binding B moiety by a disulfide bridge. After receptor-mediated endocytosis, some AB toxins undergo retrograde transport to the endoplasmic reticulum (ER) where reduction of the disulfide bond occurs. The reduced A subunit then dissociates from the holotoxin and enters the cytosol to alter its cellular target. Intoxication requires A chain separation from the holotoxin, but, for many toxins, it is unclear if reduction alone is sufficient for toxin disassembly. Here, we examined the link between reduction and disassembly for several ER-translocating toxins. We found disassembly of the reduced Escherichia coli heat-labile enterotoxin (Ltx) required an interaction with one specific ER-localized oxidoreductase: protein disulfide isomerase (PDI). In contrast, the reduction and disassembly of ricin toxin (Rtx) and Shiga toxin 1 (Stx1) were coupled events that did not require PDI and could be triggered by reductant alone. PDI-deficient cells accordingly exhibited high resistance to Ltx with continued sensitivity to Rtx and Stx1. The distinct structural organization of each AB toxin thus appears to determine whether holotoxin disassembly occurs spontaneously upon disulfide reduction or requires the additional input of PDI.


Assuntos
Ricina , Ricina/toxicidade , Ricina/química , Ricina/metabolismo , Toxina Shiga I , Isomerases de Dissulfetos de Proteínas/metabolismo , Dissulfetos
19.
J Genet ; 1022023.
Artigo em Inglês | MEDLINE | ID: mdl-37798873

RESUMO

Modern genetics research increasingly reveals that what is commonly termed Mendelian genetics occurs rarely in nature, especially with regard to the effects that genetic variation exerts on human characteristics. It has been argued that an inappropriate emphasis on Mendel's work could distort the public understanding of genetics and indeed in the UK Mendel has been completely dropped from the official school syllabus. There is a widespread misunderstanding that Mendel studied common phenotypes such as height and colour in individual pea plants. In fact, he studied a handful of specially selected phenotypes which he observed to be always dichotomous in 22 specially bred varieties of pea and studied crosses between individuals from these different varieties. This approach enabled him to study a small number of phenotypes which did in fact exhibit truly Mendelian transmission. Modern molecular genetic studies have now demonstrated that these phenotypes result from loss of function variants which result in markedly reduced activity of specific proteins and which hence have recessive effects. Understanding that Mendel studied the effects of loss of function mutations in crosses between artificially bred varieties, rather than naturally occurring variation in a population, could allow his work to continue to be taught as part of a modern genetics curriculum.


Assuntos
Cruzamento , Genética , Humanos , Fenótipo , Mutação
20.
Behav Brain Sci ; 46: e212, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694985

RESUMO

The problems with polygenic scores (PGSs) have been understated. The fact that they are ancestry-specific means that biases related to sociodemographic factors would be impossible to avoid. Additionally, the requirement to obtain DNA would have profound impacts on study design and required resources, as well as likely introducing recruitment bias. PGSs are unhelpful for social science research.


Assuntos
Herança Multifatorial , Ciências Sociais , Humanos
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