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1.
Cell ; 149(5): 1048-59, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22632969

RESUMO

Here, we use single-molecule techniques to study the aggregation of α-synuclein, the protein whose misfolding and deposition is associated with Parkinson's disease. We identify a conformational change from the initially formed oligomers to stable, more compact proteinase-K-resistant oligomers as the key step that leads ultimately to fibril formation. The oligomers formed as a result of the structural conversion generate much higher levels of oxidative stress in rat primary neurons than do the oligomers formed initially, showing that they are more damaging to cells. The structural conversion is remarkably slow, indicating a high kinetic barrier for the conversion and suggesting that there is a significant period of time for the cellular protective machinery to operate and potentially for therapeutic intervention, prior to the onset of cellular damage. In the absence of added soluble protein, the assembly process is reversed and fibrils disaggregate to form stable oligomers, hence acting as a source of cytotoxic species.


Assuntos
alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Animais , Células Cultivadas , Endopeptidase K/metabolismo , Transferência Ressonante de Energia de Fluorescência , Humanos , Cinética , Modelos Moleculares , Neurônios/metabolismo , Estresse Oxidativo , Ratos
2.
N Engl J Med ; 388(17): 1582-1596, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37099341

RESUMO

BACKGROUND: The bacille Calmette-Guérin (BCG) vaccine has immunomodulatory "off-target" effects that have been hypothesized to protect against coronavirus disease 2019 (Covid-19). METHODS: In this international, double-blind, placebo-controlled trial, we randomly assigned health care workers to receive the BCG-Denmark vaccine or saline placebo and followed them for 12 months. Symptomatic Covid-19 and severe Covid-19, the primary outcomes, were assessed at 6 months; the primary analyses involved the modified intention-to-treat population, which was restricted to participants with a negative test for severe acute respiratory syndrome coronavirus 2 at baseline. RESULTS: A total of 3988 participants underwent randomization; recruitment ceased before the planned sample size was reached owing to the availability of Covid-19 vaccines. The modified intention-to-treat population included 84.9% of the participants who underwent randomization: 1703 in the BCG group and 1683 in the placebo group. The estimated risk of symptomatic Covid-19 by 6 months was 14.7% in the BCG group and 12.3% in the placebo group (risk difference, 2.4 percentage points; 95% confidence interval [CI], -0.7 to 5.5; P = 0.13). The risk of severe Covid-19 by 6 months was 7.6% in the BCG group and 6.5% in the placebo group (risk difference, 1.1 percentage points; 95% CI, -1.2 to 3.5; P = 0.34); the majority of participants who met the trial definition of severe Covid-19 were not hospitalized but were unable to work for at least 3 consecutive days. In supplementary and sensitivity analyses that used less conservative censoring rules, the risk differences were similar but the confidence intervals were narrower. There were five hospitalizations due to Covid-19 in each group (including one death in the placebo group). The hazard ratio for any Covid-19 episode in the BCG group as compared with the placebo group was 1.23 (95% CI, 0.96 to 1.59). No safety concerns were identified. CONCLUSIONS: Vaccination with BCG-Denmark did not result in a lower risk of Covid-19 among health care workers than placebo. (Funded by the Bill and Melinda Gates Foundation and others; BRACE ClinicalTrials.gov number, NCT04327206.).


Assuntos
Adjuvantes Imunológicos , Vacina BCG , COVID-19 , Pessoal de Saúde , Humanos , Vacina BCG/uso terapêutico , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/uso terapêutico , Método Duplo-Cego , SARS-CoV-2 , Adjuvantes Imunológicos/uso terapêutico
3.
J Biol Chem ; 299(1): 102762, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463962

RESUMO

Chlamydia trachomatis (ct) is the most reported bacterial sexually transmitted infection worldwide and the leading cause of preventable blindness. Caseinolytic proteases (ClpP) from pathogenic bacteria are attractive antibiotic targets, particularly for bacterial species that form persister colonies with phenotypic resistance against common antibiotics. ClpP functions as a multisubunit proteolytic complex, and bacteria are eradicated when ClpP is disrupted. Although crucial for chlamydial development and the design of agents to treat chlamydia, the structures of ctClpP1 and ctClpP2 have yet to be solved. Here, we report the first crystal structure of full-length ClpP2 as an inactive homotetradecamer in a complex with a candidate antibiotic at 2.66 Å resolution. The structure details the functional domains of the ClpP2 protein subunit and includes the handle domain, which is integral to proteolytic activation. In addition, hydrogen-deuterium exchange mass spectroscopy probed the dynamics of ClpP2, and molecular modeling of ClpP1 predicted an assembly with ClpP2. By leveraging previous enzymatic experiments, we constructed a model of ClpP2 activation and its interaction with the protease subunits ClpP1 and ClpX. The structural information presented will be relevant for future rational drug design against these targets and will lead to a better understanding of ClpP complex formation and activation within this important human pathogen.


Assuntos
Chlamydia trachomatis , Endopeptidase Clp , Modelos Moleculares , Humanos , Antibacterianos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Chlamydia trachomatis/enzimologia , Endopeptidase Clp/química , Endopeptidase Clp/metabolismo , Cristalização , Domínios Proteicos
4.
Clin Infect Dis ; 79(1): 255-262, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38376945

RESUMO

BACKGROUND: Intussusception is the primary cause of acute bowel obstruction in infants. The majority of cases <2 years of age are classed as idiopathic, with viral infection implicated as one of the causes. Coronavirus disease 2019 (COVID-19) public health measures led to significant decreases in communicable disease prevalence. During these times, reductions in intussusception frequency were greater than would be expected with our previous understanding of its infectious etiology. METHODS: We conducted a retrospective, multistate, ecological study over a 12-year period. Monthly case numbers of "intussusception"-coded admissions (code K56.1; International Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification) were acquired from state-wide admissions data sets from New South Wales, Victoria, and Queensland, representing 77.62% of the eligible Australian population. These counts within differing jurisdictional lockdowns were compared with non-lockdown periods in order to investigate a correlation between intussusception frequency and lockdown periods. RESULTS: We found a negative association between intussusception frequency and lockdown periods in both eligible states. The largest reductions were seen in the <2-year age groups, with Victoria experiencing a 62.7% reduction (rate ratio, 0.37; P < .001) and New South Wales a 40.1% reduction (0.599; P = .006) during lockdown times. Controls for variations in lockdown restrictions between both regional and metropolitan areas also showed expected decreases. CONCLUSIONS: Our ecological study demonstrates significant decreases in the frequency of pediatric intussusception admissions during the COVID-19 lockdown periods. The unexpected magnitude of the reductions suggests that the true proportion of infectious disease-caused idiopathic intussusception is greatly underestimated.


Assuntos
COVID-19 , Intussuscepção , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Intussuscepção/epidemiologia , Intussuscepção/etiologia , Lactente , Estudos Retrospectivos , Pré-Escolar , Criança , Masculino , Feminino , Austrália/epidemiologia , Adolescente , Recém-Nascido , Adulto , Hospitalização/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto Jovem , Idoso , New South Wales/epidemiologia , Queensland/epidemiologia , Vitória/epidemiologia
5.
PLoS Med ; 21(6): e1004414, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38857311

RESUMO

BACKGROUND: In many countries, infant vaccination with acellular pertussis (aP) vaccines has replaced use of more reactogenic whole-cell pertussis (wP) vaccines. Based on immunological and epidemiological evidence, we hypothesised that substituting the first aP dose in the routine vaccination schedule with wP vaccine might protect against IgE-mediated food allergy. We aimed to compare reactogenicity, immunogenicity, and IgE-mediated responses of a mixed wP/aP primary schedule versus the standard aP-only schedule. METHODS AND FINDINGS: OPTIMUM is a Bayesian, 2-stage, double-blind, randomised trial. In stage one, infants were assigned (1:1) to either a first dose of a pentavalent wP combination vaccine (DTwP-Hib-HepB, Pentabio PT Bio Farma, Indonesia) or a hexavalent aP vaccine (DTaP-Hib-HepB-IPV, Infanrix hexa, GlaxoSmithKline, Australia) at approximately 6 weeks old. Subsequently, all infants received the hexavalent aP vaccine at 4 and 6 months old as well as an aP vaccine at 18 months old (DTaP-IPV, Infanrix-IPV, GlaxoSmithKline, Australia). Stage two is ongoing and follows the above randomisation strategy and vaccination schedule. Ahead of ascertainment of the primary clinical outcome of allergist-confirmed IgE-mediated food allergy by 12 months old, here we present the results of secondary immunogenicity, reactogenicity, tetanus toxoid IgE-mediated immune responses, and parental acceptability endpoints. Serum IgG responses to diphtheria, tetanus, and pertussis antigens were measured using a multiplex fluorescent bead-based immunoassay; total and specific IgE were measured in plasma by means of the ImmunoCAP assay (Thermo Fisher Scientific). The immunogenicity of the mixed schedule was defined as being noninferior to that of the aP-only schedule using a noninferiority margin of 2/3 on the ratio of the geometric mean concentrations (GMR) of pertussis toxin (PT)-IgG 1 month after the 6-month aP. Solicited adverse reactions were summarised by study arm and included all children who received the first dose of either wP or aP. Parental acceptance was assessed using a 5-point Likert scale. The primary analyses were based on intention-to-treat (ITT); secondary per-protocol (PP) analyses were also performed. The trial is registered with ANZCTR (ACTRN12617000065392p). Between March 7, 2018 and January 13, 2020, 150 infants were randomised (75 per arm). PT-IgG responses of the mixed schedule were noninferior to the aP-only schedule at approximately 1 month after the 6-month aP dose [GMR = 0·98, 95% credible interval (0·77 to 1·26); probability (GMR > 2/3) > 0·99; ITT analysis]. At 7 months old, the posterior median probability of quantitation for tetanus toxoid IgE was 0·22 (95% credible interval 0·12 to 0·34) in both the mixed schedule group and in the aP-only group. Despite exclusions, the results were consistent in the PP analysis. At 6 weeks old, irritability was the most common systemic solicited reaction reported in wP (65 [88%] of 74) versus aP (59 [82%] of 72) vaccinees. At the same age, severe systemic reactions were reported among 14 (19%) of 74 infants after wP and 8 (11%) of 72 infants after aP. There were 7 SAEs among 5 participants within the first 6 months of follow-up; on blinded assessment, none were deemed to be related to the study vaccines. Parental acceptance of mixed and aP-only schedules was high (71 [97%] of 73 versus 69 [96%] of 72 would agree to have the same schedule again). CONCLUSIONS: Compared to the aP-only schedule, the mixed schedule evoked noninferior PT-IgG responses, was associated with more severe reactions, but was well accepted by parents. Tetanus toxoid IgE responses did not differ across the study groups. TRIAL REGISTRATION: Trial registered at the Australian and New Zealand Clinical 207 Trial Registry (ACTRN12617000065392p).


Assuntos
Vacina contra Difteria, Tétano e Coqueluche , Esquemas de Imunização , Imunoglobulina E , Humanos , Lactente , Método Duplo-Cego , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Feminino , Masculino , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/efeitos adversos , Austrália , Vacinas Combinadas/imunologia , Vacinas Combinadas/efeitos adversos , Vacinas Combinadas/administração & dosagem , Vacina contra Coqueluche/imunologia , Vacina contra Coqueluche/efeitos adversos , Vacina contra Coqueluche/administração & dosagem , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/prevenção & controle , Vacina Antipólio de Vírus Inativado/imunologia , Vacina Antipólio de Vírus Inativado/efeitos adversos , Vacina Antipólio de Vírus Inativado/administração & dosagem , Vacinas Anti-Haemophilus/imunologia , Vacinas Anti-Haemophilus/efeitos adversos , Vacinas Anti-Haemophilus/administração & dosagem , Coqueluche/prevenção & controle , Coqueluche/imunologia , Imunogenicidade da Vacina , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia
6.
Am J Transplant ; 24(2S1): S266-S304, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38431361

RESUMO

Intestine remains the least frequently transplanted solid organ, although the survival and quality-of-life benefits of transplant to individuals with irreversible intestinal failure have been well demonstrated. The trend seen over the past 15 years of fewer listings and fewer transplants appears to be continuing, most noticeably in infants, children, and adolescents. There were only 146 additions to the intestine waiting list in 2022, and the proportion of adult candidates continues to increase, so that now 61% of the intestine waiting list are adult candidates. There has been little change in the distribution by sex, race and ethnicity, or primary diagnosis on the waiting list, or for those receiving transplant. The transplant rate for adults has decreased to 55.6 transplants per 100 patient-years, but the pediatric transplant rate remains relatively stable at 22.8 transplants per 100 patient-years. The decrease in transplant rates for adults is primarily the result of falling rates for those listed for combined intestine-liver, and this is reflected in the pretransplant mortality rates, which are twice as high for candidates in need of both organs compared with those listed for intestine alone. Overall, intestine transplant numbers decreased to a total of 82 intestine transplants in 2022, only one above the lowest ever value of 81 in 2019. No major changes were seen in the immunosuppression protocols, with most recipients having induction therapy and tacrolimus-based maintenance. Graft failure rates appear to have improved at 1, 3, and 5 years for intestine without liver, but this is not seen for combined intestine-liver. Graft and patient survival are better for pediatric recipients compared with adult recipients for both liver-inclusive and liver-exclusive transplant. Rates of posttransplant lymphoproliferative disorder are higher for recipients of intestine without liver.


Assuntos
Transplante de Fígado , Obtenção de Tecidos e Órgãos , Adulto , Lactente , Adolescente , Humanos , Criança , Estados Unidos/epidemiologia , Intestinos/transplante , Terapia de Imunossupressão , Listas de Espera , Etnicidade , Sobrevivência de Enxerto , Doadores de Tecidos
7.
Am J Transplant ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38331046

RESUMO

The Scientific Registry of Transplant Recipients has previously reported the effects of adjusting for demographic variables, including race, in the Centers for Medicare & Medicaid Services (CMS) organ procurement organization (OPO) performance metrics: donation rate and transplant rate. CMS chose not to adjust for most demographic variables other than age (for the transplant rate), arguing that there is no biological reason that these variables would affect the organ donation/utilization decision. However, organ donation is a process based on altruism and trust, not a simple biological phenomenon. Focusing only on biological impacts on health ignores other pathways through which demographic factors can influence OPO outcomes. In this study, we update analyses of demographic adjustment on the OPO metrics for 2020 with a specific focus on adjusting for race. We find that adjusting for race would lead to 8 OPOs changing their CMS tier rankings, including 2 OPOs that actually overperform the national rate among non-White donors improving from a tier 3 ranking (facing decertification without possibility of recompeting) to a tier 2 ranking (allowing the possibility of recompeting). Incorporation of stratified and risk-adjusted metrics in public reporting of OPO performance could help OPOs identify areas for improvement within specific demographic categories.

8.
EMBO J ; 39(18): e104494, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32643832

RESUMO

Cells respond to endolysosome damage by either repairing the damage or targeting damaged endolysosomes for degradation via lysophagy. However, the signals regulating the decision for repair or lysophagy are poorly characterised. Here, we show that the Parkinson's disease (PD)-related kinase LRRK2 is activated in macrophages by pathogen- or sterile-induced endomembrane damage. LRRK2 recruits the Rab GTPase Rab8A to damaged endolysosomes as well as the ESCRT-III component CHMP4B, thereby favouring ESCRT-mediated repair. Conversely, in the absence of LRRK2 and Rab8A, damaged endolysosomes are targeted to lysophagy. These observations are recapitulated in macrophages from PD patients where pathogenic LRRK2 gain-of-function mutations result in the accumulation of endolysosomes which are positive for the membrane damage marker Galectin-3. Altogether, this work indicates that LRRK2 regulates endolysosomal homeostasis by controlling the balance between membrane repair and organelle replacement, uncovering an unexpected function for LRRK2, and providing a new link between membrane damage and PD.


Assuntos
Membranas Intracelulares/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Macrófagos/metabolismo , Animais , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos/genética , Endossomos/metabolismo , Ativação Enzimática/genética , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Lisossomos/genética , Lisossomos/metabolismo , Camundongos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Células RAW 264.7 , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
9.
J Bacteriol ; 205(5): e0009923, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37092988

RESUMO

The obligate intracellular human pathogen Chlamydia trachomatis (Ctr) undergoes a complex developmental cycle in which the bacterium differentiates between two functionally and morphologically distinct forms: the elementary body (EB) and the reticulate body (RB). The EB is the smaller, infectious, nondividing form which initiates infection of a susceptible host cell, whereas the RB is the larger, non-infectious form which replicates within a membrane-bound vesicle called an inclusion. The mechanism(s) which drives differentiation between these developmental forms is poorly understood. Bulk protein turnover is likely required for chlamydial differentiation given the significant differences in the protein repertoires and functions of the EB and RB. We hypothesize that periplasmic protein turnover is also critical for the reorganization of an RB into an EB, referred to as secondary differentiation. Ct441 is a periplasmic protease ortholog of tail-specific proteases (i.e., Tsp, Prc) and is expressed in Ctr during secondary differentiation. We investigated the effect of altering Tsp expression on developmental cycle progression. Through assessment of bacterial morphology and infectious progeny production, we found that both overexpression and CRISPR interference/dCas9 (CRISPRi)-mediated knockdown of Tsp negatively impacted chlamydial development through different mechanisms. We also confirmed that catalytic activity is required for the negative effect of overexpression and confirmed the effect of the mutation in in vitro assays. Electron microscopic assessments during knockdown experiments revealed a defect in EB morphology, directly linking Tsp function to secondary differentiation. These data implicate Ct441/Tsp as a critical factor in secondary differentiation. IMPORTANCE The human pathogen Chlamydia trachomatis is the leading cause of preventable infectious blindness and bacterial sexually transmitted infections worldwide. This pathogen has a unique developmental cycle that alternates between distinct forms. However, the key processes of chlamydial development remain obscure. Uncovering the mechanisms of differentiation between its metabolically and functionally distinct developmental forms may foster the discovery of novel Chlamydia-specific therapeutics and limit development of resistant bacterial populations derived from the clinical use of broad-spectrum antibiotics. In this study, we investigate chlamydial tail-specific protease (Tsp) and its function in chlamydial growth and development. Our work implicates Tsp as essential to chlamydial developmental cycle progression and indicates that Tsp is a potential drug target for Chlamydia infections.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Humanos , Chlamydia trachomatis/metabolismo , Endopeptidases/metabolismo , Antibacterianos/farmacologia , Proteólise , Proteínas de Bactérias/metabolismo
10.
Am J Transplant ; 23(2 Suppl 1): S264-S299, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37132347

RESUMO

There has been just over 30 years of experience in clinical intestine transplant. A rise in demand until 2007 with improving transplant outcomes preceded a subsequent fall in demand due, at least in part, to improvements in pretransplant care of patients with intestinal failure. Over the past 10 to 12 years, there has been no suggestion of an increase in demand and, particularly for adult transplant, there may be a continued trend toward fewer additions to the waiting list and fewer transplants, especially in those needing combined intestine-liver transplant. In addition, over the same period there has been no noticeable improvement in graft survival, with 1- and 5-year graft failure rates averaging 21.6% and 52.5%, respectively, for intestine-alone transplants and 28.6% and 47.2%, respectively, for combined intestine-liver allografts.


Assuntos
Transplante de Fígado , Obtenção de Tecidos e Órgãos , Transplantes , Adulto , Humanos , Estados Unidos/epidemiologia , Intestinos/transplante , Listas de Espera , Sobrevivência de Enxerto , Doadores de Tecidos
11.
Am J Transplant ; 23(5): 608-610, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36740191

RESUMO

The 2022 Scientific Registry of Transplant Recipients Consensus Conference "People Driven Transplant Metrics" offered an opportunity for a diverse group of stakeholders in the solid organ transplant community to exchange ideas about what information and metrics are important to different stakeholders. Participating patients and family members called on the transplant community to cease using the term "discards" to refer to donated organs that are not transplanted.


Assuntos
Transplante de Rim , Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Seleção do Doador
12.
J Clin Immunol ; 43(8): 1706-1723, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37405544

RESUMO

Although a more efficient adaptive humoral immune response has been proposed to underlie the usually favorable outcome of pediatric COVID-19, the breadth of viral and vaccine cross-reactivity toward the ever-mutating Spike protein among variants of concern (VOCs) has not yet been compared between children and adults. We assessed antibodies to conformational Spike in COVID-19-naïve children and adults vaccinated by BNT162b2 and ChAdOx1, and naturally infected with SARS-CoV-2 Early Clade, Delta, and Omicron. Sera were analyzed against Spike including naturally occurring VOCs Alpha, Beta, Gamma, Delta, and Omicron BA.1, BA.2, BA.5, BQ.1.1, BA2.75.2, and XBB.1, and variants of interest Epsilon, Kappa, Eta, D.2, and artificial mutant Spikes. There was no notable difference between breadth and longevity of antibody against VOCs in children and adults. Vaccinated individuals displayed similar immunoreactivity profiles across variants compared with naturally infected individuals. Delta-infected patients had an enhanced cross-reactivity toward Delta and earlier VOCs compared to patients infected by Early Clade SARS-CoV-2. Although Omicron BA.1, BA.2, BA.5, BQ.1.1, BA2.75.2, and XBB.1 antibody titers were generated after Omicron infection, cross-reactive binding against Omicron subvariants was reduced across all infection, immunization, and age groups. Some mutations, such as 498R and 501Y, epistatically combined to enhance cross-reactive binding, but could not fully compensate for antibody-evasive mutations within the Omicron subvariants tested. Our results reveal important molecular features central to the generation of high antibody titers and broad immunoreactivity that should be considered in future vaccine design and global serosurveillance in the context of limited vaccine boosters available to the pediatric population.


Assuntos
COVID-19 , Vacinas , Criança , Humanos , Adulto , SARS-CoV-2 , Formação de Anticorpos , Vacina BNT162 , Anticorpos
13.
Liver Transpl ; 29(1): 26-33, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35696252

RESUMO

Recent changes to liver allocation replaced donor service areas with circles as the geographic unit of allocation. Circle-based allocation might increase the number of transplantation centers and candidates required to place a liver, thereby increasing the logistical burden of making and responding to offers on organ procurement organizations and transplantation centers. Circle-based allocation might also increase distribution time and cold ischemia time (CIT), particularly in densely populated areas of the country, thereby decreasing allocation efficiency. Using Scientific Registry of Transplant Recipient data from 2019 to 2021, we evaluated the number of transplantation centers and candidates required to place livers in the precircles and postcircles eras, nationally and by donor region. Compared with the precircles era, livers were offered to more candidates (5 vs. 9; p < 0.001) and centers (3 vs. 5; p < 0.001) before being accepted; more centers were involved in the match run by offer number 50 (9 vs. 14; p < 0.001); CIT increased by 0.2 h (5.9 h vs. 6.1 h; p < 0.001); and distribution time increased by 2.0 h (30.6 h vs. 32.6 h; p < 0.001). Increased burden varied geographically by donor region; livers recovered in Region 9 were offered to many more candidates (4 vs. 12; p < 0.001) and centers (3 vs. 8; p < 0.001) before being accepted, resulting in the largest increase in CIT (5.4 h vs. 6.0 h; p < 0.001). Circle-based allocation is associated with increased logistical burdens that are geographically heterogeneous. Continuous distribution systems will have to be carefully designed to avoid exacerbating this problem.


Assuntos
Transplante de Fígado , Obtenção de Tecidos e Órgãos , Humanos , Transplante de Fígado/efeitos adversos , Doadores de Tecidos , Transplantados , Fígado/cirurgia , Listas de Espera
14.
Clin Transplant ; 37(9): e15017, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37204074

RESUMO

BACKGROUND: The Organ Procurement and Transplantation Network (OPTN) is eliminating geographic boundaries in liver allocation, in favor of continuous distribution. Continuous distribution allocates organs via a composite allocation score (CAS): a weighted sum of attributes like medical urgency, candidate biology, and placement efficiency. The opportunity this change represents, to include new variables and features for prioritizing candidates, will require lengthy and contentious discussions to establish community consensus. Continuous distribution could instead be implemented rapidly by computationally translating the allocation priorities for pediatric, status 1, and O/B blood type liver candidates that are presently implemented via geographic boundaries into points and weights in a CAS. METHODS: Using simulation with optimization, we designed a CAS that is minimally disruptive to existing prioritizations, and that eliminates geographic boundaries and minimizes waitlist deaths without harming vulnerable populations. RESULTS: Compared with Acuity Circles (AC) in a 3-year simulation, our optimized CAS decreased deaths from 7771.2 to 7678.8 while decreasing average (272.66 NM vs. 264.30 NM) and median (201.14 NM vs. 186.49 NM) travel distances. Our CAS increased travel only for high MELD and status 1 candidates (423.24 NM vs. 298.74 NM), and reduced travel for other candidates (198.98 NM vs. 250.09 NM); overall travel burden decreased. CONCLUSION: Our CAS reduced waitlist deaths by sending livers for high-MELD and status 1 candidates farther, while keeping livers for lower MELD candidates nearby. This advanced computational method can be applied again after wider discussions of adding new priorities conclude; our method designs score weightings to achieve any specified feasible allocation outcomes.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Criança , Listas de Espera
15.
Brain ; 145(12): 4349-4367, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36074904

RESUMO

Parkinson's disease is a common incurable neurodegenerative disease. The identification of genetic variants via genome-wide association studies has considerably advanced our understanding of the Parkinson's disease genetic risk. Understanding the functional significance of the risk loci is now a critical step towards translating these genetic advances into an enhanced biological understanding of the disease. Impaired mitophagy is a key causative pathway in familial Parkinson's disease, but its relevance to idiopathic Parkinson's disease is unclear. We used a mitophagy screening assay to evaluate the functional significance of risk genes identified through genome-wide association studies. We identified two new regulators of PINK1-dependent mitophagy initiation, KAT8 and KANSL1, previously shown to modulate lysine acetylation. These findings suggest PINK1-mitophagy is a contributing factor to idiopathic Parkinson's disease. KANSL1 is located on chromosome 17q21 where the risk associated gene has long been considered to be MAPT. While our data do not exclude a possible association between the MAPT gene and Parkinson's disease, they provide strong evidence that KANSL1 plays a crucial role in the disease. Finally, these results enrich our understanding of physiological events regulating mitophagy and establish a novel pathway for drug targeting in neurodegeneration.


Assuntos
Mitofagia , Doença de Parkinson , Humanos , Estudo de Associação Genômica Ampla , Mitofagia/fisiologia , Doenças Neurodegenerativas , Doença de Parkinson/metabolismo , Proteínas Quinases/genética , Proteínas tau/genética
16.
Brain ; 145(12): 4398-4408, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35903017

RESUMO

Disease-modifying treatments are currently being trialled in multiple system atrophy. Approaches based solely on clinical measures are challenged by heterogeneity of phenotype and pathogenic complexity. Neurofilament light chain protein has been explored as a reliable biomarker in several neurodegenerative disorders but data on multiple system atrophy have been limited. Therefore, neurofilament light chain is not yet routinely used as an outcome measure in multiple system atrophy. We aimed to comprehensively investigate the role and dynamics of neurofilament light chain in multiple system atrophy combined with cross-sectional and longitudinal clinical and imaging scales and for subject trial selection. In this cohort study, we recruited cross-sectional and longitudinal cases in a multicentre European set-up. Plasma and CSF neurofilament light chain concentrations were measured at baseline from 212 multiple system atrophy cases, annually for a mean period of 2 years in 44 multiple system atrophy patients in conjunction with clinical, neuropsychological and MRI brain assessments. Baseline neurofilament light chain characteristics were compared between groups. Cox regression was used to assess survival; receiver operating characteristic analysis to assess the ability of neurofilament light chain to distinguish between multiple system atrophy patients and healthy controls. Multivariate linear mixed-effects models were used to analyse longitudinal neurofilament light chain changes and correlated with clinical and imaging parameters. Polynomial models were used to determine the differential trajectories of neurofilament light chain in multiple system atrophy. We estimated sample sizes for trials aiming to decrease neurofilament light chain levels. We show that in multiple system atrophy, baseline plasma neurofilament light chain levels were better predictors of clinical progression, survival and degree of brain atrophy than the neurofilament light chain rate of change. Comparative analysis of multiple system atrophy progression over the course of disease, using plasma neurofilament light chain and clinical rating scales, indicated that neurofilament light chain levels rise as the motor symptoms progress, followed by deceleration in advanced stages. Sample size prediction suggested that significantly lower trial participant numbers would be needed to demonstrate treatment effects when incorporating plasma neurofilament light chain values into multiple system atrophy clinical trials in comparison to clinical measures alone. In conclusion, neurofilament light chain correlates with clinical disease severity, progression and prognosis in multiple system atrophy. Combined with clinical and imaging analysis, neurofilament light chain can inform patient stratification and serve as a reliable biomarker of treatment response in future multiple system atrophy trials of putative disease-modifying agents.


Assuntos
Atrofia de Múltiplos Sistemas , Humanos , Estudos de Coortes , Estudos Transversais , Filamentos Intermediários , Proteínas de Neurofilamentos , Biomarcadores , Progressão da Doença
17.
Med J Aust ; 218(11): 528-541, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37248802

RESUMO

Vaccination in pregnancy is the best strategy to reduce complications from influenza or pertussis infection in infants who are too young to be protected directly from vaccination. Pregnant women are also at risk of influenza complications preventable through antenatal vaccination. Both vaccines are funded under the National Immunisation Program for pregnant women in Australia, but coverage is not routinely reported nationally. We reviewed all reported Australian maternal influenza and pertussis vaccine coverage data for the period 2016-2021, to identify gaps and information needs. Maternal influenza vaccine coverage was suboptimal at < 58% for 2016-2018, with higher coverage of 62-75% reported in two states (Victoria and Western Australia) for 2019-2021. Maternal pertussis vaccine coverage from 2016 was generally higher than for influenza at > 70%, with the highest jurisdictional coverage of 89% reported in Western Australia in 2020. Vaccination rates were often suboptimal among First Nations pregnant women and up to 20% lower than among non-First Nations Australian women; while data were limited, coverage was low among culturally and linguistically diverse women and among women of lower socio-economic status. Jurisdictional perinatal data collections were the best source of information on antenatal vaccine coverage but were only available for a minority of the population; a nationally consistent systematic approach is lacking. Timely and comprehensive data are needed to provide feedback to improve maternal vaccination coverage, particularly among groups with higher risk and/or low uptake, and as new vaccines are recommended, including COVID-19 vaccination.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Complicações Infecciosas na Gravidez , Coqueluche , Lactente , Feminino , Gravidez , Humanos , Vacinas contra Influenza/uso terapêutico , Vacina contra Coqueluche , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Vacinas contra COVID-19 , Gestantes , Vacinação , Coqueluche/epidemiologia , Coqueluche/prevenção & controle , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Inquéritos e Questionários , Vitória
18.
Future Oncol ; 19(9): 663-678, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37128990

RESUMO

Aim: To provide perspective on patient-reported outcome measurement (PROM) instruments to adopt in patients diagnosed with gynecological cancers. Methods: A systematic search was conducted to identify PROMs developed for or applied in gynecological cancer populations. PROMs identified in more than one study subsequently underwent assessment according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria. Results: Overall, 55 PROMs were identified within the gynecological cancer setting, and 20 were assessed according to COSMIN guidelines. Most PROMs had limited information reported, but a best fit approach was adopted to recommend a number of instruments for use in patients with gynecological cancer. Conclusion: Further study to assess the methodological quality of each PROM utilized in gynecological cancers is warranted to endorse the recommendations of this review.


Gynecological cancers are cancers which occur in the reproductive system of women. The cervical cancer screening program and development of new treatments mean that women with gynecological cancers are now living longer than before. However, these new treatments may have side effects that can affect the quality of life of women with cancer. Many care providers now agree that looking at women's quality of life during their gynecological cancer journey is an important part of their treatment. Patient-reported outcome measurements (PROMs) are questionnaires that the patient completes to measure their symptoms and quality of life. There are a lot of PROMs available to choose from, and it can be difficult to select one that is relevant and understandable for all women with gynecological cancer. This article searched the literature to find all PROMs that can be completed by women with gynecological cancer and then measured each of the PROM's quality. PROM quality was measured by looking at validity (whether the questionnaire measures what it is supposed to measure), reliability (that the questionnaire is not subject to different errors in measuring), and sensitivity (that the questionnaire can measure changes in questionnaire scores over time). Overall, this study found that there were a few PROMs that were of good enough quality to be completed by women with gynecological cancers. These questionnaires are called the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire Cervical Cancer Module (EORTC QLQ-CX24), the Functional Assessment of Cancer Therapy - General (FACT-G), European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire Endometrial Cancer (EORTC QLQ-EN24), Functional Assessment of Cancer Therapy Gynecologic Oncology Group ­ Neurotoxicity (FACT-GOG/Ntx), Functional Assessment of Cancer Therapy ­ Ovarian (FACT-O) and Female Sexual Function Index (FSFI). Each questionnaire can be filled out by women with different types of gynecological cancer, and the FSFI measures sexual problems that women may experience after cancer treatment.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Inquéritos e Questionários , Psicometria , Medidas de Resultados Relatados pelo Paciente
19.
Pediatr Nephrol ; 38(3): 859-866, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35833990

RESUMO

BACKGROUND: COVID-19 disease in kidney transplant (KT) recipients is associated with increased morbidity, mortality, and hospitalization rates. Unfortunately, KT recipients also have a reduced response to SARS-CoV-2 immunization. The primary aim of this study was to assess immunologic response to SARS-CoV-2 mRNA vaccines in pediatric kidney transplant recipients 12-18 years of age. Secondary aims were to assess response rates following a third immunization and determine factors that influence immunization response. METHODS: Pediatric KT recipients in a single tertiary center received SARS-CoV-2 mRNA vaccination as per local protocol. SARS-CoV-2 immunoglobulin (IgG) was measured following second and/or third vaccination. Demographics including patient factors (age, gender, and underlying disease), transplant factors (time and type of transplant), and immunosuppression (induction, maintenance, and immunomodulatory therapies such as IVIG) were collected from the medical records. RESULTS: Of 20 participants, 10 (50%) responded following a two-dose vaccine schedule, which increased to 15 (75%) after three doses. Maintenance immunosuppression affected immunologic response, with azathioprine demonstrating a higher rate of response to vaccine compared to mycophenolate (100% vs. 38%, p = 0.04). Increasing prednisolone dose had a negative impact on immunologic response (0.01 mg/kg/day increase: OR 1.60 95% CI 1.01 to 2.57). Tacrolimus dose and trough levels, age, time post-transplant, underlying disease, and other immunosuppression did not impact immunologic response. CONCLUSIONS: Pediatric KT recipients had similar response rates following SARS-CoV-2 immunization as adult KT recipients. Immunologic response improved following a third immunization. Choice of antimetabolite and prednisolone dosing influenced the rate of response. A higher resolution version of the Graphical abstract is available as Supplementary Information.


Assuntos
COVID-19 , Transplante de Rim , Adulto , Humanos , Criança , SARS-CoV-2 , Transplante de Rim/efeitos adversos , COVID-19/prevenção & controle , Vacinação , Transplantados , Imunossupressores/efeitos adversos , RNA Mensageiro , Anticorpos Antivirais
20.
J Paediatr Child Health ; 59(11): 1217-1222, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37664891

RESUMO

AIM: Australian and New Zealand guidelines recommend that live vaccines be postponed for 11 months after treatment of Kawasaki disease (KD) with intravenous immunoglobulin (IVIG). We aimed to describe patterns of live-vaccine administration after KD treatment, focusing on the measles-mumps-rubella/measles-mumps-rubella-varicella (MMR/MMRV) vaccines, and to compare real-world practice with current recommendations. METHODS: We combined data from inpatient Electronic Health Records and the Australian Immunisation Register for all children who received IVIG for the treatment of KD under the age of 5 years at two Australian tertiary children's hospitals over a 12-year period. Children who received IVIG <11 months before a scheduled MMR/MMRV were deemed 'at risk' of breaching the guidelines, and those whose subsequent vaccination occurred <11 months after the IVIG were deemed to have 'breached' the guidelines. RESULTS: Of those at risk, three-quarters (76%) breached the guidelines for their first MMR/MMRV. Findings were similar (50%-80%) for the second MMR/MMRV dose. CONCLUSIONS: The majority of Australian children treated for KD with IVIG may not be optimally protected by MMRV vaccination. Immunisation systems should address this avoidable risk.


Assuntos
Varicela , Sarampo , Síndrome de Linfonodos Mucocutâneos , Caxumba , Rubéola (Sarampo Alemão) , Criança , Humanos , Lactente , Pré-Escolar , Imunoglobulinas Intravenosas/uso terapêutico , Caxumba/prevenção & controle , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Austrália , Vacina contra Varicela , Vacina contra Sarampo-Caxumba-Rubéola , Varicela/prevenção & controle , Herpesvirus Humano 3 , Sarampo/prevenção & controle , Rubéola (Sarampo Alemão)/prevenção & controle
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