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1.
Mol Cell ; 84(19): 3843-3859.e8, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39096899

RESUMO

Despite the numerous sequencing methods available, the diversity in RNA size and chemical modification makes it difficult to capture all RNAs in a cell. We developed a method that combines quasi-random priming with template switching to construct sequencing libraries from RNA molecules of any length and with any type of 3' modifications, allowing for the sequencing of virtually all RNA species. Our ligation-independent detection of all types of RNA (LIDAR) is a simple, effective tool to identify and quantify all classes of coding and non-coding RNAs. With LIDAR, we comprehensively characterized the transcriptomes of mouse embryonic stem cells, neural progenitor cells, mouse tissues, and sperm. LIDAR detected a much larger variety of tRNA-derived RNAs (tDRs) compared with traditional ligation-dependent sequencing methods and uncovered tDRs with blocked 3' ends that had previously escaped detection. Therefore, LIDAR can capture all RNAs in a sample and uncover RNA species with potential regulatory functions.


Assuntos
RNA de Transferência , Animais , RNA de Transferência/genética , RNA de Transferência/metabolismo , Camundongos , Análise de Sequência de RNA/métodos , Masculino , Células-Tronco Embrionárias Murinas/metabolismo , Transcriptoma , Células-Tronco Neurais/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Espermatozoides/metabolismo
2.
Cell ; 161(5): 1215-1228, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-26000489

RESUMO

Toward development of a precision medicine framework for metastatic, castration-resistant prostate cancer (mCRPC), we established a multi-institutional clinical sequencing infrastructure to conduct prospective whole-exome and transcriptome sequencing of bone or soft tissue tumor biopsies from a cohort of 150 mCRPC affected individuals. Aberrations of AR, ETS genes, TP53, and PTEN were frequent (40%-60% of cases), with TP53 and AR alterations enriched in mCRPC compared to primary prostate cancer. We identified new genomic alterations in PIK3CA/B, R-spondin, BRAF/RAF1, APC, ß-catenin, and ZBTB16/PLZF. Moreover, aberrations of BRCA2, BRCA1, and ATM were observed at substantially higher frequencies (19.3% overall) compared to those in primary prostate cancers. 89% of affected individuals harbored a clinically actionable aberration, including 62.7% with aberrations in AR, 65% in other cancer-related genes, and 8% with actionable pathogenic germline alterations. This cohort study provides clinically actionable information that could impact treatment decisions for these affected individuals.


Assuntos
Perfilação da Expressão Gênica/métodos , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Estudos de Coortes , Humanos , Masculino , Mutação , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico
3.
Nat Rev Genet ; 23(2): 73-88, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34545247

RESUMO

More than a century ago, August Weissman defined a distinction between the germline (responsible for propagating heritable information from generation to generation) and the perishable soma. A central motivation for this distinction was to argue against the inheritance of acquired characters, as the germline was partly defined by its protection from external conditions. However, recent decades have seen an explosion of studies documenting the intergenerational and transgenerational effects of environmental conditions, forcing a re-evaluation of how external signals are sensed by, or communicated to, the germline epigenome. Here, motivated by the centrality of small RNAs in paradigms of epigenetic inheritance, we review across species the myriad examples of intercellular RNA trafficking from nurse cells or somatic tissues to developing gametes.


Assuntos
Epigênese Genética/genética , Epigenômica , Regulação da Expressão Gênica/genética , Interação Gene-Ambiente , Células Germinativas/metabolismo , RNA/genética , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Células Germinativas/citologia , Humanos , Modelos Genéticos , RNA/metabolismo , Transporte de RNA/genética
4.
Cell ; 155(7): 1532-44, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24360276

RESUMO

During each life cycle, germ cells preserve and pass on both genetic and epigenetic information. In C. elegans, the ALG-3/4 Argonaute proteins are expressed during male gametogenesis and promote male fertility. Here, we show that the CSR-1 Argonaute functions with ALG-3/4 to positively regulate target genes required for spermiogenesis. Our findings suggest that ALG-3/4 functions during spermatogenesis to amplify a small RNA signal that represents an epigenetic memory of male-specific gene expression. CSR-1, which is abundant in mature sperm, appears to transmit this memory to offspring. Surprisingly, in addition to small RNAs targeting male-specific genes, we show that males also harbor an extensive repertoire of CSR-1 small RNAs targeting oogenesis-specific mRNAs. Together, these findings suggest that C. elegans sperm transmit not only the genome but also epigenetic binary signals in the form of Argonaute/small RNA complexes that constitute a memory of gene expression in preceding generations.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Epigênese Genética , Proteínas de Ligação a RNA/metabolismo , Espermatogênese , Animais , Caenorhabditis elegans/genética , Feminino , Masculino , Pequeno RNA não Traduzido/metabolismo , Transdução de Sinais , Espermatozoides , Transcrição Gênica
5.
Nature ; 604(7905): 287-291, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418635

RESUMO

Thermophotovoltaics (TPVs) convert predominantly infrared wavelength light to electricity via the photovoltaic effect, and can enable approaches to energy storage1,2 and conversion3-9 that use higher temperature heat sources than the turbines that are ubiquitous in electricity production today. Since the first demonstration of 29% efficient TPVs (Fig. 1a) using an integrated back surface reflector and a tungsten emitter at 2,000 °C (ref. 10), TPV fabrication and performance have improved11,12. However, despite predictions that TPV efficiencies can exceed 50% (refs. 11,13,14), the demonstrated efficiencies are still only as high as 32%, albeit at much lower temperatures below 1,300 °C (refs. 13-15). Here we report the fabrication and measurement of TPV cells with efficiencies of more than 40% and experimentally demonstrate the efficiency of high-bandgap tandem TPV cells. The TPV cells are two-junction devices comprising III-V materials with bandgaps between 1.0 and 1.4 eV that are optimized for emitter temperatures of 1,900-2,400 °C. The cells exploit the concept of band-edge spectral filtering to obtain high efficiency, using highly reflective back surface reflectors to reject unusable sub-bandgap radiation back to the emitter. A 1.4/1.2 eV device reached a maximum efficiency of (41.1 ± 1)% operating at a power density of 2.39 W cm-2 and an emitter temperature of 2,400 °C. A 1.2/1.0 eV device reached a maximum efficiency of (39.3 ± 1)% operating at a power density of 1.8 W cm-2 and an emitter temperature of 2,127 °C. These cells can be integrated into a TPV system for thermal energy grid storage to enable dispatchable renewable energy. This creates a pathway for thermal energy grid storage to reach sufficiently high efficiency and sufficiently low cost to enable decarbonization of the electricity grid.


Assuntos
Eletricidade , Temperatura Alta , Raios Infravermelhos , Temperatura
6.
Am J Hum Genet ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39317201

RESUMO

The ClinGen Hereditary Breast, Ovarian, and Pancreatic Cancer (HBOP) Variant Curation Expert Panel (VCEP) is composed of internationally recognized experts in clinical genetics, molecular biology, and variant interpretation. This VCEP made specifications for the American College of Medical Genetics and Association for Molecular Pathology (ACMG/AMP) guidelines for the ataxia telangiectasia mutated (ATM) gene according to the ClinGen protocol. These gene-specific rules for ATM were modified from the ACMG/AMP guidelines and were tested against 33 ATM variants of various types and classifications in a pilot curation phase. The pilot revealed a majority agreement between the HBOP VCEP classifications and the ClinVar-deposited classifications. Six pilot variants had conflicting interpretations in ClinVar, and re-evaluation with the VCEP's ATM-specific rules resulted in four that were classified as benign, one as likely pathogenic, and one as a variant of uncertain significance (VUS) by the VCEP, improving the certainty of interpretations in the public domain. Overall, 28 of the 33 pilot variants were not VUS, leading to an 85% classification rate. The ClinGen-approved, modified rules demonstrated value for improved interpretation of variants in ATM.

7.
Am J Hum Genet ; 111(3): 584-593, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38417439

RESUMO

Variants of uncertain significance (VUSs) in BRCA2 are a common result of hereditary cancer genetic testing. While more than 4,000 unique VUSs, comprised of missense or intronic variants, have been identified in BRCA2, the few missense variants now classified clinically as pathogenic or likely pathogenic are predominantly located in the region encoding the C-terminal DNA binding domain (DBD). We report on functional evaluation of the influence of 462 BRCA2 missense variants affecting the DBD on DNA repair activity of BRCA2 using a homology-directed DNA double-strand break repair assay. Of these, 137 were functionally abnormal, 313 were functionally normal, and 12 demonstrated intermediate function. Comparisons with other functional studies of BRCA2 missense variants yielded strong correlations. Sequence-based in silico prediction models had high sensitivity, but limited specificity, relative to the homology-directed repair assay. Combining the functional results with clinical and genetic data in an American College of Medical Genetics (ACMG)/Association for Molecular Pathology (AMP)-like variant classification framework from a clinical testing laboratory, after excluding known splicing variants and functionally intermediate variants, classified 431 of 442 (97.5%) missense variants (129 as pathogenic/likely pathogenic and 302 as benign/likely benign). Functionally abnormal variants classified as pathogenic by ACMG/AMP rules were associated with a slightly lower risk of breast cancer (odds ratio [OR] 5.15, 95% confidence interval [CI] 3.43-7.83) than BRCA2 DBD protein truncating variants (OR 8.56, 95% CI 6.03-12.36). Overall, functional studies of BRCA2 variants using validated assays substantially improved the variant classification yield from ACMG/AMP models and are expected to improve clinical management of many individuals found to harbor germline BRCA2 missense VUS.


Assuntos
Neoplasias da Mama , Predisposição Genética para Doença , Humanos , Feminino , Proteína BRCA2/genética , Testes Genéticos , Mutação de Sentido Incorreto/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células Germinativas/patologia , DNA
8.
J Immunol ; 212(2): 271-283, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37982696

RESUMO

Highly self-reactive T cells are censored from the repertoire by both central and peripheral tolerance mechanisms upon receipt of high-affinity TCR signals. Clonal deletion is considered a major driver of central tolerance; however, other mechanisms such as induction of regulatory T cells and functional impairment have been described. An understanding of the interplay between these different central tolerance mechanisms is still lacking. We previously showed that impaired clonal deletion to a model tissue-restricted Ag did not compromise tolerance. In this study, we determined that murine T cells that failed clonal deletion were rendered functionally impaired in the thymus. Programmed cell death protein 1 (PD-1) was induced in the thymus and was required to establish cell-intrinsic tolerance to tissue-restricted Ag in CD8+ thymocytes independently of clonal deletion. In bone marrow chimeras, tolerance was not observed in PD-L1-deficient recipients, but tolerance was largely maintained following adoptive transfer of tolerant thymocytes or T cells to PD-L1-deficient recipients. However, CRISPR-mediated ablation of PD-1 in tolerant T cells resulted in broken tolerance, suggesting different PD-1 signaling requirements for establishing versus maintaining tolerance. Finally, we showed that chronic exposure to high-affinity Ag supported the long-term maintenance of tolerance. Taken together, our study identifies a critical role for PD-1 in establishing central tolerance in autoreactive T cells that escape clonal deletion. It also sheds light on potential mechanisms of action of anti-PD-1 pathway immune checkpoint blockade and the development of immune-related adverse events.


Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Camundongos , Animais , Receptor de Morte Celular Programada 1/genética , Tolerância Central , Linfócitos T CD8-Positivos , Timo , Antígenos , Tolerância Imunológica
10.
J Gen Intern Med ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937368

RESUMO

BACKGROUND: Patients hospitalized with COVID-19 can clinically deteriorate after a period of initial stability, making optimal timing of discharge a clinical and operational challenge. OBJECTIVE: To determine risks for post-discharge readmission and death among patients hospitalized with COVID-19. DESIGN: Multicenter retrospective observational cohort study, 2020-2021, with 30-day follow-up. PARTICIPANTS: Adults admitted for care of COVID-19 respiratory disease between March 2, 2020, and February 11, 2021, to one of 180 US hospitals affiliated with the HCA Healthcare system. MAIN MEASURES: Readmission to or death at an HCA hospital within 30 days of discharge was assessed. The area under the receiver operating characteristic curve (AUC) was calculated using an internal validation set (33% of the HCA cohort), and external validation was performed using similar data from six academic centers associated with a hospital medicine research network (HOMERuN). KEY RESULTS: The final HCA cohort included 62,195 patients (mean age 61.9 years, 51.9% male), of whom 4704 (7.6%) were readmitted or died within 30 days of discharge. Independent risk factors for death or readmission included fever within 72 h of discharge; tachypnea, tachycardia, or lack of improvement in oxygen requirement in the last 24 h; lymphopenia or thrombocytopenia at the time of discharge; being ≤ 7 days since first positive test for SARS-CoV-2; HOSPITAL readmission risk score ≥ 5; and several comorbidities. Inpatient treatment with remdesivir or anticoagulation were associated with lower odds. The model's AUC for the internal validation set was 0.73 (95% CI 0.71-0.74) and 0.66 (95% CI 0.64 to 0.67) for the external validation set. CONCLUSIONS: This large retrospective study identified several factors associated with post-discharge readmission or death in models which performed with good discrimination. Patients 7 or fewer days since test positivity and who demonstrate potentially reversible risk factors may benefit from delaying discharge until those risk factors resolve.

11.
Environ Sci Technol ; 58(1): 570-579, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38150661

RESUMO

Chemical methods for the extraction and refinement of technologically critical rare earth elements (REEs) are energy-intensive, hazardous, and environmentally destructive. Current biobased extraction systems rely on extremophilic organisms and generate many of the same detrimental effects as chemical methodologies. The mesophilic methylotrophic bacterium Methylobacterium extorquens AM1 was previously shown to grow using electronic waste by naturally acquiring REEs to power methanol metabolism. Here we show that growth using electronic waste as a sole REE source is scalable up to 10 L with consistent metal yields without the use of harsh acids or high temperatures. The addition of organic acids increases REE leaching in a nonspecific manner. REE-specific bioleaching can be engineered through the overproduction of REE-binding ligands (called lanthanophores) and pyrroloquinoline quinone. REE bioaccumulation increases with the leachate concentration and is highly specific. REEs are stored intracellularly in polyphosphate granules, and genetic engineering to eliminate exopolyphosphatase activity increases metal accumulation, confirming the link between phosphate metabolism and biological REE use. Finally, we report the innate ability of M. extorquens to grow using other complex REE sources, including pulverized smartphones, demonstrating the flexibility and potential for use as a recovery platform for these critical metals.


Assuntos
Resíduo Eletrônico , Metais Terras Raras , Metais , Ligantes
12.
PLoS Genet ; 17(3): e1009416, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33661909

RESUMO

Beyond the haploid genome, mammalian sperm carry a payload of epigenetic information with the potential to modulate offspring phenotypes. Recent studies show that the small RNA repertoire of sperm is remodeled during post-testicular maturation in the epididymis. Epididymal maturation has also been linked to changes in the sperm methylome, suggesting that the epididymis might play a broader role in shaping the sperm epigenome. Here, we characterize the genome-wide methylation landscape in seven germ cell populations from throughout the male reproductive tract. We find very few changes in the cytosine methylation landscape between testicular germ cell populations and cauda epididymal sperm, demonstrating that the sperm methylome is stable throughout post-testicular maturation. Although our sequencing data suggested that caput epididymal sperm exhibit a highly unusual methylome, follow-up studies revealed that this resulted from contamination of caput sperm by extracellular DNA. Extracellular DNA formed web-like structures that ensnared sperm, and was present only in sperm samples obtained from the caput epididymis and vas deferens of virgin males. Curiously, contaminating extracellular DNA was associated with citrullinated histone H3, potentially resulting from a PAD-driven genome decondensation process. Taken together, our data emphasize the stability of cytosine methylation in mammalian sperm, and identify a surprising, albeit transient, period during which sperm are associated with extracellular DNA.


Assuntos
Citosina/metabolismo , Metilação de DNA , Epigenoma , Maturação do Esperma/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Animais , Diferenciação Celular/genética , Ácidos Nucleicos Livres , Ilhas de CpG , Epididimo/citologia , Epididimo/metabolismo , Feminino , Masculino , Camundongos , Espermatozoides/citologia
13.
J Arthroplasty ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39384078

RESUMO

INTRODUCTION: Extensor mechanism disruption is a devastating complication following total knee arthroplasty (TKA). Despite its morbidity, there is no consensus regarding the optimal treatment strategy. We aimed to determine the survivorship, clinical outcomes, and improvement in patient-reported outcome measures (PROMs) after primary repair of acute extensor mechanism disruptions following primary or revision TKA. METHODS: A retrospective review identified 41 acute extensor mechanism disruptions (33 primary TKAs and eight revision TKAs) from 2015 to 2021. The study group was 56% women, the mean BMI was 33, the mean age was 66 years, and the mean follow-up was three years. Extensor mechanism disruption occurred at the patellar tendon (n = 17), quadriceps tendon (n = 15), and patella (n = 9) at a mean of 10 months following TKA. Surgical management was primary repair (n = 30) or primary repair with augmentation (allograft or autograft) (n = 11). Kaplan-Meier analysis estimated survivorship. RESULTS: The two-year survivorship free from all-cause reoperation was 72 and 23% following primary and revision TKA, respectively (P = 0.013). The two-year survivorship free from all-cause reoperation was 66% for primary repair versus 61% for primary repair with augmentation (P = 0.95). There were 17 (41%) patients who underwent reoperation, most commonly for re-rupture (n = 4) in two primary repairs and two primary repairs with augmentation (P = 0.288). Revision TKA (P = 0.049) and increased time from disruption to repair (P = 0.039) were risk factors for reoperation. The mean extensor lag did not significantly improve, nor did patients see improvement in their PROMs. CONCLUSION: After primary and revision TKA, acute extensor mechanism disruption treated with primary repair with or without augmentation had very poor early survivorship free from all-cause reoperation. Patients should be counseled appropriately, and alternative surgical techniques should be considered.

14.
J Arthroplasty ; 39(11): 2787-2792, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38776991

RESUMO

BACKGROUND: Plain radiographs remain the standard for diagnosing osteoarthritis (OA). Total hip arthroplasty (THA) is generally offered only for advanced OA by plain radiographs. Advanced imaging is used as an adjunct to assess OA severity in cases of progressive symptoms with less advanced OA by plain radiographs. The objective of this study was to compare outcomes following THA in patients who have advanced OA visualized by plain radiographs to patients who have less severe OA visualized by plain radiographs. METHODS: From February 2016 to February 2020, 93 patients who had Kellgren-Lawrence (KL) grade 0 to 2 OA and underwent THA were identified. The median age was 65 years, and 55% were women. They were matched 1:3 to patients who underwent THA for KL 4 OA based on age, sex, body mass index, and Charlson Comorbidity Index. The primary outcome was achievement of the Hip Injury and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) minimum clinically important difference, substantial clinical benefit, and patient-acceptable symptom state at 1 year postoperatively. RESULTS: There was no difference between the KL 0 to 2 and KL 4 cohorts in the achievement of HOOS JR minimum clinically important difference (86 versus 85.6%, P = .922), substantial clinical benefit (81.7 versus 80.2%, P = .751), or patient-acceptable symptom state (89.2 versus 85.6%, P = .374). The KL 0 to 2 cohort had a similar improvement in their 2-year HOOS JR (42.5 versus 38.6, P = .019). CONCLUSIONS: In this series, there was no difference in outcomes following primary THA between patients who have severe OA on plain radiographs (KL 4) compared to those who have less severe OA (KL 0 to 2). In the setting of severe symptoms and the absence of advanced OA on radiographs, advanced imaging can be used to guide treatment and select patients who could benefit from THA.


Assuntos
Artroplastia de Quadril , Osteoartrite do Quadril , Radiografia , Humanos , Feminino , Masculino , Osteoartrite do Quadril/cirurgia , Osteoartrite do Quadril/diagnóstico por imagem , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Estudos Retrospectivos , Índice de Gravidade de Doença
15.
J Arthroplasty ; 39(4): 1083-1087.e1, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37871864

RESUMO

BACKGROUND: Periprosthetic femur fracture (PFF) following total hip arthroplasty (THA) is a leading cause of early reoperation. The objective of this study was to compare rates of periprosthetic joint infection (PJI) and reoperation following PFFs occurring early postoperatively to those that occurred late. METHODS: We retrospectively identified 173 consecutive surgically managed PFFs following primary THA. Cases were categorized as "early" if they occurred within 90 days of THA (n = 117) or "late" if they occurred following the initial 90 days (n = 56). Mean age at time of PFF was 68 years (range, 26 to 96) and 60% were women. Mean body mass index was 29 (range, 16 to 52). Mean follow-up was 2 years (range, 0 to 13). Kaplan-Meier survival analysis estimated cumulative incidences of PJI and reoperation. RESULTS: Early PFFs had higher 2-year cumulative incidence of PJI (11% versus 0%, P < .001) and reoperation (24% versus 13%, P = .110). Following early PFF, 27 patients required reoperation (ie, 13 for PJI, 5 for instability, 2 for re-fracture, 2 for painful hardware, 2 for non-union, 1 for adverse local tissue reaction, 1 for aseptic loosening, and 1 for leg-length discrepancy). Following late PFF, 5 patients required reoperation (ie, 3 for instability, 1 for re-fracture, and 1 for non-union). CONCLUSIONS: There are greater incidences of PJIs and overall reoperations following early PFFs compared to late PFFs after THA. In addition to focusing efforts on prevention of early PFFs, surgeons should consider antiseptic interventions to mitigate the increased risk of PJI after treatment of early PFF.


Assuntos
Artroplastia de Quadril , Fraturas do Fêmur , Prótese de Quadril , Fraturas Periprotéticas , Infecções Relacionadas à Prótese , Humanos , Feminino , Masculino , Artroplastia de Quadril/efeitos adversos , Reoperação/efeitos adversos , Estudos Retrospectivos , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Fêmur/cirurgia , Fraturas do Fêmur/epidemiologia , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fraturas Periprotéticas/epidemiologia , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Prótese de Quadril/efeitos adversos , Fatores de Risco
16.
J Arthroplasty ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147074

RESUMO

BACKGROUND: The purpose of this study was to determine implant survivorship and functional outcomes for revision total knee arthroplasty (rTKA) with contemporary rotating-hinge knee implants. METHODS: A retrospective review identified 115 rTKAs using contemporary rotating-hinge implants from 2014 to 2018 for the treatment of instability (34, 30%), reimplantation after periprosthetic joint infection (PJI) (33, 29%), aseptic loosening (25, 22%), arthrofibrosis (14, 12%), periprosthetic fracture (4, 3%), osteolysis (4, 3%), and femoral component fracture (1, 1%). There were 70 women (61%), and the mean age was 67 years (range, 27 to 94). The mean follow-up was 3 years (range, 2 to 6). Kaplan-Meier analysis and Cox proportional hazard models estimated survivorship. RESULTS: The re-revision rate was 20% (23 of 115) at an average of 18 months postoperatively. Re-revision indications included PJI (n = 14), aseptic loosening (n = 4), arthrofibrosis (n = 2), instability/malalignment (n = 1), femoral stem fracture (n = 1), and hinge mechanism disruption (n = 1). At 2 and 5 years, survivorship free from all-cause re-revision was 86 and 64%, and survivorship free from re-revision for aseptic loosening was 100 and 87%, respectively. Use of a rotating-hinge implant in reimplantation after PJI was a risk factor for subsequent re-revision (hazard ratio = 2.4, P = 0.046). On a radiographic review of unrevised rotating-hinges, there were major radiolucent lines around 2 femoral and 5 tibial components. The mean Knee Injury and Osteoarthritis Outcomes Score for Joint Replacement increased from 43 preoperatively to 60 at 1 year (P < 0.001). CONCLUSIONS: In patients treated with a rotating-hinge implant for rTKA, there were relatively poor 2-year (86%) and 5-year (64%) survivorship free from all-cause re-revision, most commonly due to PJI. Midterm survivorship free from re-revision for aseptic loosening was modest (87%). There should be a goal to mitigate complications in complex rTKAs with rotating-hinge implants, namely PJI.

17.
J Arthroplasty ; 39(10): 2607-2614.e1, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38735554

RESUMO

BACKGROUND: Interprosthetic femur fractures (IPFFs) are a rare, but devastating complication following total joint arthroplasty. There is limited evidence to help guide their management. The purpose of this study was to describe the features, treatment, and outcomes of surgically managed IPFFs. METHODS: We retrospectively identified 75 patients who had 76 IPFFs. The mean age at the time of IPFF was 75 years (range, 29 to 94), and 78% were women. The mean body mass index was 30 (range, 19 to 51), and the mean follow-up was 3 years (range, 0 to 14). There were 16 Vancouver B1 fractures, 28 Vancouver B2 fractures, 2 Vancouver B3 fractures, and 30 Vancouver C fractures. All B1 fractures underwent open reduction internal fixation (ORIF). All Vancouver B2 and B3 fractures underwent revision arthroplasty, including 1 proximal femur replacement and 1 total femur replacement. Vancouver C fractures were treated with ORIF (n = 20), distal femoral replacement (n = 9), and in 1 case, total femur replacement (n = 1). Kaplan-Meier survivorship was used to calculate 2-year survival free from all-cause reoperation and periprosthetic joint infection (PJI). RESULTS: The 2-year survivorship-free rate from reoperation was 71%. There were 18 reoperations following initial surgical management of the IPFF, including 9 for infection, 3 for refracture, 3 for nonunion, 2 for hardware failure, and 1 for instability. An initial IPFF involving a stemmed femoral total knee arthroplasty component was associated with increased risk for reoperation (P = .007) and PJI (P = .044). There was no difference in survivorship free of reoperation between IPFFs managed with ORIF or revision arthroplasty (P = .72). CONCLUSIONS: An IPFF is a devastating complication following total joint arthroplasty with high reoperation rates, most commonly secondary to PJI. Those IPFFs that occurred between 2 stemmed components were at the highest risk for reoperation.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Fraturas do Fêmur , Reoperação , Humanos , Feminino , Reoperação/estatística & dados numéricos , Idoso , Artroplastia do Joelho/efeitos adversos , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/etiologia , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Adulto , Fraturas Periprotéticas/cirurgia , Fraturas Periprotéticas/etiologia , Fixação Interna de Fraturas/efeitos adversos , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Complicações Pós-Operatórias/epidemiologia
18.
J Arthroplasty ; 39(7): 1765-1770, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38301980

RESUMO

BACKGROUND: There is no consensus on whether direct anterior approach (DAA) or postero-lateral approach (PLA) total hip arthroplasty (THA) confers a lower risk of postoperative complications. Robotic assistance in THA results in a more consistently accurate component position compared to manual THA. The objective of this study was to compare rates of dislocation, reoperation, revision, and patient-reported outcome measures between patients undergoing DAA and PLA robotic-assisted primary THA. METHODS: We identified 2,040 consecutive robotic-assisted primary THAs performed for primary osteoarthritis, using DAA (n = 497) or PLA (n = 1,542) between 2017 and 2020. The mean follow-up was 18 months. Kaplan-Meier analysis estimated survivorship free of dislocation, reoperation, and revision. Achievement of patient acceptable symptom state and minimum clinically important difference were used to compare changes in the Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS JR) and Visual Analog Scale. RESULTS: Dislocation was rare in this series (14 in 2,040, 0.7%), including 1 of 497 (0.2%) in the DAA cohort and 13 of 1,542 (0.8%) in the PLA cohort (P = .210). There was no difference in 2-year reoperation-free survivorship (97.8 versus 98.6%, P = .59) or revision-free survivorship (98.8 versus 99.0%, P = .87) at any time point. After controlling for age, sex, and body mass index, there was no difference in dislocation, reoperation, or revision. At 6-week follow-up, after controlling for age, sex, and body mass index, patients in the DAA cohort had higher odds of achieving HOOS JR minimum clinically important difference (odds ratio = 2.01, P = .012) and HOOS JR patient acceptable symptom state (odds ratio = 1.72, P = .028). There were no differences in patient-reported outcome measures by 3 months. CONCLUSIONS: For robotic-assisted primary THA, DAA may confer enhanced early (<6 weeks) functional recovery compared to the PLA, but there was no significant difference in postoperative dislocation, reoperation, or revision rates.


Assuntos
Artroplastia de Quadril , Osteoartrite do Quadril , Medidas de Resultados Relatados pelo Paciente , Complicações Pós-Operatórias , Reoperação , Procedimentos Cirúrgicos Robóticos , Humanos , Artroplastia de Quadril/métodos , Reoperação/estatística & dados numéricos , Feminino , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Idoso , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Resultado do Tratamento , Adulto
19.
J Nurs Care Qual ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361883

RESUMO

BACKGROUND: The Johns Hopkins Activity and Mobility Program is a systematic approach to measure and improve patient mobility. PURPOSE: The purpose of this study was to evaluate the relationship between mobility loss and quality outcomes. METHODS: A retrospective cohort study design was used. Patients were categorized into 3 groups (gain, loss, no change in mobility) using the Johns Hopkins Highest Level of Mobility (JH-HLM) scores. The association between mobility loss and falls risk, in-hospital mortality, delirium, discharge to a facility, length of stay, and 30 day readmissions were assessed. RESULTS: Those who lost mobility were more at risk of being a high fall risk, in-hospital mortality, delirium, discharging to a facility, and had 48% longer lengths of stay. There was no association between mobility loss and 30-day readmissions. CONCLUSIONS: Loss of mobility assessed using JH-HLM scores is associated with worse patient outcomes.

20.
Semin Cancer Biol ; 78: 5-16, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582171

RESUMO

Disseminated non-dividing (dormant) cancer cells as well as those in equilibrium with the immune response remain the major challenge for successful treatment of cancer. The equilibrium between disseminated dormant cancer cells and the immune system is reminiscent of states that can occur during infection or allogeneic tissue and cell transplantation. We discuss here the major competing models of how the immune system achieves a self nonself discrimination (pathogen/danger patterns, quorum, and coinhibition/tuning models), and suggest that taking advantage of a combination of the proposed mechanisms in each model may lead to increased efficacy in tackling cancer cell dormancy.


Assuntos
Suscetibilidade a Doenças , Modelos Biológicos , Neoplasias/etiologia , Neoplasias/metabolismo , Microambiente Tumoral , Gerenciamento Clínico , Suscetibilidade a Doenças/imunologia , Humanos , Sistema Imunitário , Técnicas de Diagnóstico Molecular , Neoplasias/diagnóstico , Transplante/efeitos adversos , Transplante/métodos
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