RESUMO
BACKGROUND: Impairment of cellular cholesterol trafficking is at the heart of atherosclerotic lesions formation. This involves egress of cholesterol from the lysosomes and 2 lysosomal proteins, the NPC1 (Niemann-Pick C1) and NPC2 that promotes cholesterol trafficking. However, movement of cholesterol out the lysosome and how disrupted cholesterol trafficking leads to atherosclerosis is unclear. As the Wnt ligand, Wnt5a inhibits the intracellular accumulation of cholesterol in multiple cell types, we tested whether Wnt5a interacts with the lysosomal cholesterol export machinery and studied its role in atherosclerotic lesions formation. METHODS: We generated mice deleted for the Wnt5a gene in vascular smooth muscle cells. To establish whether Wnt5a also protects against cholesterol accumulation in human vascular smooth muscle cells, we used a CRISPR/Cas9 guided nuclease approach to generate human vascular smooth muscle cells knockout for Wnt5a. RESULTS: We show that Wnt5a is a crucial component of the lysosomal cholesterol export machinery. By increasing lysosomal acid lipase expression, decreasing metabolic signaling by the mTORC1 (mechanistic target of rapamycin complex 1) kinase, and through binding to NPC1 and NPC2, Wnt5a senses changes in dietary cholesterol supply and promotes lysosomal cholesterol egress to the endoplasmic reticulum. Consequently, loss of Wnt5a decoupled mTORC1 from variations in lysosomal sterol levels, disrupted lysosomal function, decreased cholesterol content in the endoplasmic reticulum, and promoted atherosclerosis. CONCLUSIONS: These results reveal an unexpected function of the Wnt5a pathway as essential for maintaining cholesterol homeostasis in vivo.
Assuntos
Aterosclerose/metabolismo , Colesterol/metabolismo , Lisossomos/metabolismo , Proteína Wnt-5a/metabolismo , Animais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteína C1 de Niemann-Pick/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteína Wnt-5a/genéticaRESUMO
Concerns about implant durability and technical difficulty continue to make total wrist arthroplasties a specialized procedure with a narrow scope of indications. As a result, more routinely performed total or partial wrist arthrodesis continues to maintain popularity over arthroplasty. However, wrist motion preservation is undoubtedly preferable for patients and current literature is trending to more favorable outcomes for total wrist arthroplasties. In the setting of the evolving role of wrist arthroplasties in clinical practice, it is important to focus on providing hand surgeons a practical approach to incorporating total wrist arthroplasty into the treatment toolbox available to them when treating patients with painful wrist arthritis.
Assuntos
Artrite , Artroplastia de Substituição , Humanos , Punho/cirurgia , Artroplastia , Articulação do Punho/cirurgia , Artrodese , InternacionalidadeRESUMO
PURPOSE: Intramedullary (IM) screw fixation is gaining popularity in the treatment of metacarpal fractures. Despite its rapid adoption, there is a paucity of evidence regarding parameters to optimize effectiveness. This study aimed to quantify the relationship between stability, IM screw size, and canal fill using a cadaveric model. METHODS: Thirty cadaveric metacarpals (14 index, 13 middle, and three ring fingers; mean age: 58.3 years, range: 48-70) were selected to allow for canal fill ratios of 0.7-1.1 for screws sized 3.0, 3.5, and 4.5 mm. Metacarpals underwent a 45° volar-dorsal osteotomy at the midpoint before fixation with an IM screw. Specimens were subjected to 100 cycles of loading at 10 N, 20 N, and 30 N before load-to-failure testing. Correlation coefficients for angular displacement on the final cycle at each load, peak load to failure, and average stiffness were assessed. RESULTS: Correlation coefficients for the angular displacement on the 100th cycle were as follows: 10 N, R = 0.62, 20 N, R = 0.57, and 30N, R = 0.58. Correlation values for peak load to failure as a function of canal fit were as follows: 3.0 mm, R = 0.5, 3.5 mm, R = 0.17, and 4.5 mm, R = 0.44. The canal fill ratio that intersected the line-of-best fit at an angular deformity of 10° was 0.74. Average peak forces for 3.0-, 3.5-, and 4.5-mm screws were 79.5, 136.5, and 179.6 N, respectively. Average stiffness for each caliber was 14.8, 33.4, and 52.3 N/mm. CONCLUSIONS: Increasing screw diameter and IM fill resulted in more stable fixation, but marginal gains were seen in ratios >0.9. A minimum fill ratio of 0.74 was sufficient to withstand forces of early active motion with angular deformity <10°. CLINICAL RELEVANCE: An understanding of the relationship of IM fill ratio of metacarpal screws to fracture stability may provide a framework for clinicians to optimally size these implants.
RESUMO
BACKGROUND: Multidisciplinary transitional care services reduce readmissions for high-risk patients, but it is unclear if health system costs to offer these intensive services are offset by avoidance of higher downstream expenditures. OBJECTIVE: To evaluate net costs for a health system offering transitional care services DESIGN: One-year pragmatic, randomized trial PARTICIPANTS: Adults aged ≥ 18 without a usual source of follow-up care at the time of hospital discharge were enrolled through a high-volume, urban academic medical center in Chicago, IL, USA, from September 2015 through February 2016. INTERVENTIONS: Eligible patients were silently randomized before discharge by an automated electronic health record algorithm allocating them in a 1:3 ratio to receive routine coordination of post-discharge care (RC) versus being offered intensive, multidisciplinary transitional care (TC) services. MAIN MEASUREMENTS: Health system costs were collected from facility administrative systems and transformed to standardized costs using Medicare reference files. Multivariable generalized linear models estimated proportional differences in net costs over one year. KEY RESULTS: Study patients (489 TC; 164 RC) had a mean age of 44 years; 34% were uninsured, 55% had public insurance, and 49% self-identified as Black or Latinx. Over 90 days, cost differences between groups were not statistically significant. Over 180 days, the TC group had 41% lower ED/observation costs (adjusted cost ratio [aCR], 0.59; 95% CI, 0.36-0.97), 50% lower inpatient costs (aCR, 0.50; 95% CI, 0.27-0.95), and 41% lower total healthcare costs (aCR, 0.59; 95% CI, 0.36-0.99) than the RC group. Over 365 days, total cost differences remained of similar magnitude but no longer were statistically significant. CONCLUSIONS: Offering TC services for vulnerable adults at discharge reduced net health system expenditures over 180 days. The promising economic case for multidisciplinary transitional care interventions warrants further research. TRIAL REGISTRATION: National Clinical Trials Registry (NCT03066492).
Assuntos
Cuidado Transicional , Adulto , Humanos , Idoso , Estados Unidos , Alta do Paciente , Gastos em Saúde , Assistência ao Convalescente , MedicareRESUMO
ABSTRACT: Numerous methods for surgical correction of sagittal synostosis have been described in the literature, yielding similar outcomes. At the authors' institution, surgical approaches to correct this condition have evolved over the past few decades, including Π, H-type craniectomies (Renier), endoscopic suturectomy, and our current technique, the FLAG procedure. Our aim is to review the evolution of these surgical techniques at our institution and compare patient outcomes. A retrospective review was performed on consecutive patients undergoing correction for craniosynostosis from 2008 to 2018. All patients with a diagnosis of nonsyndromic isolated sagittal craniosynostosis were included and classified into one of 4 groups by the type of surgical correction performed (H-type, FLAG, endoscopic, other). The authors identified 166 consecutive patients with a mean age at time of surgery of 6.7 ± 4.0 months. 91 (54.8%) carried a diagnosis of nonsyndromic sagittal synostosis. 63 patients underwent H-type procedures, 9 underwent FLAG procedures, 5 underwent endoscopic procedures, and 14 were classified as other (distraction or other implant). Perioperatively, the FLAG group had the shortest ICU stay (1.3 days, P < 0.05), postoperative transfusion requirement (42cc pRBC, P < 0.001), and complication rate (0.0%). The endoscopic group had the shortest surgical time at 2.00âhours (p < 0.001). No statistically significant difference in cranial index or revision procedures between the four groups was identified. Overall, the mean length of follow-up was 25.3 months. All procedures had similar results for cranial index with decreased surgical time, transfusion volume, and hospital stay seen in FLAG and endoscopic groups.
Assuntos
Craniossinostoses , Procedimentos de Cirurgia Plástica , Craniossinostoses/cirurgia , Craniotomia , Endoscopia , Humanos , Estudos Retrospectivos , Crânio/cirurgia , Resultado do TratamentoRESUMO
Septic, inflammatory, or crystal-induced arthritis are common etiologies of wrist pain without antecedent trauma associated with pain, loss of motion, swelling, redness, and warmth. In this report, we detail the case of granulocytic sarcoma of the wrist that presented as acute wrist pain, swelling, and limitation in motion. Granulocytic sarcoma is an exceedingly rare extramedullary tumor associated with acute myeloblastic leukemia. It may be found in any part of the body; however, upper extremity involvement is uncommon. To our knowledge, this is the first description of granulocytic sarcoma occurring in the wrist joint.
Assuntos
Leucemia Mieloide Aguda , Sarcoma Mieloide , Humanos , Dor , Sarcoma Mieloide/complicações , Sarcoma Mieloide/diagnóstico , PunhoRESUMO
BACKGROUND: The purpose of this study is to assess the feasibility of a novel microporous annealed particle (MAP) scaffolding hydrogel to enable both articular cartilage and subchondral bone biointegration and chondrocyte regeneration in a rat knee osteochondral defect model. METHODS: An injectable, microporous scaffold was engineered and modified to match the mechanical properties of articular cartilage. Two experimental groups were utilized-negative saline control and MAP gel treatment group. Saline and MAP gel were injected into osteochondral defects created in the knees of Sprague-Dawley rats. Photo-annealing of the MAP gel was performed. Qualitative histologic and immunohistochemical analysis was performed of the treated defects at 2, 4, and 8 weeks postsurgery. RESULTS: The injectable MAP gel successfully annealed and was sustained within the osteochondral defect at each timepoint. Treatment with MAP gel resulted in maintained size of the osteochondral defect with evidence of tissue ingrowth and increased glycosaminoglycan production, whereas the control defects presented with evidence of disorganized scar tissue. Additionally, there was no significant inflammatory response to the MAP gel noted on histology. CONCLUSIONS: We have demonstrated the successful delivery of an injectable, flowable MAP gel scaffold into a rat knee osteochondral defect with subsequent annealing and stable integration into the healing wound. The flowable nature of this scaffold allows for minimally invasive application, for example, via an arthroscopic approach for management of wrist arthritis. The MAP gel was noted to fill the osteochondral defect and maintain the defect dimensions and provide a continuous and smooth surface for cartilage regeneration, suggesting its ability to provide a stable scaffold for tissue ingrowth. Future chemical, mechanical, and biological gel modifications may improve objective evidence of cartilage regeneration.
Assuntos
Cartilagem Articular , Animais , Cartilagem Articular/cirurgia , Condrócitos , Articulação do Joelho , Porosidade , Ratos , Ratos Sprague-Dawley , Alicerces TeciduaisRESUMO
BACKGROUND: There is limited experimental evidence on transitional care interventions beyond 30 days post-discharge and in vulnerable populations. OBJECTIVE: Evaluate effects of a transitional care practice (TC) that comprehensively addresses patients' medical and psychosocial needs following hospital discharge. DESIGN: Pragmatic, randomized comparative effectiveness trial. PATIENTS: Adults discharged from an initial emergency, observation, or inpatient hospital encounter with no trusted usual source of care. INTERVENTIONS: TC intervention included a scheduled post-discharge appointment at the TC practice, where a multidisciplinary team comprehensively assessed patients' medical and psychosocial needs, addressed modifiable barriers, and subsequent linkage to a new primary care source. Routine Care involved assistance scheduling a post-discharge appointment with a primary care provider that often partnered with the hospital where the initial encounter occurred. MAIN MEASURES: The primary outcome was a binary indicator of death or additional hospital encounters within 90 days of initial discharge. Secondary outcomes included any additional hospital encounters, and counts of hospital encounters, over 180 days. KEY RESULTS: Four hundred ninety patients were randomized to TC intervention and 164 to Routine Care; 34.6% were uninsured, 49.7% had Medicaid, and 57.4% were homeless or lived in a high-poverty area. There was no significant difference between arms in the 90-day probability of death or additional hospital encounters (relative risk [RR] 0.89; 0.91; 95% confidence interval [CI] 0.74-1.13). However, TC patients had 37% and 35% lower probability of any inpatient admission over 90 days (RR 0.63; 95% CI 0.43-0.91) and 180 days (RR 0.65; 95% CI 0.47-0.89), respectively. Over 180 days, TC patients had 42% fewer inpatient admissions (incidence rate ratio 0.58; 95% CI 0.37-0.90). CONCLUSIONS: Among patients randomized to a patient-centered transitional care intervention, there was no significant reduction in 90-day probability of death or additional hospital encounters. However, there were significant decreases in measures of inpatient admissions over 180 days. TRIAL REGISTRATION: clinicaltrials.gov identifier NCT03066492.
Assuntos
Alta do Paciente/tendências , Assistência Centrada no Paciente/métodos , Assistência Centrada no Paciente/tendências , Cuidado Transicional/tendências , Populações Vulneráveis , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
INTRODUCTION: Staged, tissue expander-based implant reconstruction continues to be the most common mode of breast reconstruction after mastectomy and has evolved significantly for the past 60 years. Prepectoral acellular dermal matrix (ADM)-assisted breast reconstruction is gaining popularity with complication rates similar to total submuscular and ADM-assisted partially submuscular reconstruction. Ours is among the first reports comparing postoperative pain and early functional outcomes between 2-stage ADM-assisted prepectoral and partial submuscular breast reconstruction. METHODS: Patients reconstructed with a 2-stage, ADM-assisted prepectoral approach were case matched with patients who had undergone ADM-assisted, partial submuscular reconstruction. Demographics and complication rates were compared. Primary outcomes included postoperative pain, number of days until full active shoulder range of motion was achieved, and postoperative days until drain removal. RESULTS: Forty-five breasts among 24 patients were reconstructed with ADM-assisted prepectoral tissue expanders after mastectomy and 90 breasts among 48 patients were reconstructed with ADM-assisted partial submuscular placement. There was a similarly acceptable complication profile between the 2 groups. The prepectoral group had significantly lower inpatient pain scores, required significantly less intravenous opioids and less oral opioids as outpatients. The prepectoral group saw a return to full active range of shoulder motion in half the number days of the partial submuscular group. Drain duration was similar between groups. CONCLUSIONS: Prepectoral ADM-assisted breast reconstruction can be performed safely and with significantly less pain and earlier return to function than partial submuscular expander placement. Expander placement exclusively in the prepectoral pocket did not result in increased drain duration while affording patients the benefits of avoiding surgical elevation of the pectoralis muscle.
Assuntos
Derme Acelular , Implante Mamário/métodos , Mamoplastia/métodos , Músculos Peitorais/cirurgia , Expansão de Tecido/métodos , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Mastectomia/métodos , Pessoa de Meia-Idade , Satisfação do Paciente/estatística & dados numéricosRESUMO
BACKGROUND: Infection is the most significant complication in implant-based breast reconstruction, potentially leading to reconstructive failure. We hypothesized that implementation of an evidence-based protocol marked by preoperative decolonization and sterility optimization would result in a decline in postoperative infection rates. METHODS: Informed by a literature review, we developed an evidence-based, perioperative infection prevention protocol implemented in 2015. Surgical outcomes were compared between patients who had undergone implant-based breast reconstruction before and after protocol implementation. A Fisher exact test was used to compare infection rates before and after protocol implementation. A logistic regression analysis was modeled to evaluate the impact of the protocol on infection rate while controlling for nonmodifiable risk factors. RESULTS: Three hundred fifty-eight breasts underwent reconstruction before protocol implementation and 135 afterward. Patients were similar in terms of demographics and surgical characteristics. There was a significantly reduced incidence of clinically relevant infection after protocol implementation (9.5%-2.9%, P = 0.013). Logistic regression analysis confirmed that the protocol was independently associated with a decrease in infection risk (odds ratio, 0.244; P = 0.021). After protocol implementation, no gram-positive bacteria were isolated among cultures obtained from infected periprosthetic fluid. Radiation and drain duration greater than 21 days were independently associated with greater risk for infection. CONCLUSIONS: Our evidence-based protocol was associated with a significant decline in infection rates among implant-based breast reconstruction patients and was particularly effective for gram-positive infections. We will continue to use this protocol in our practice and will consider future directions for addressing gram-negative infections as well.
Assuntos
Infecções Bacterianas/prevenção & controle , Implante Mamário/métodos , Protocolos Clínicos , Medicina Baseada em Evidências , Infecções Relacionadas à Prótese/prevenção & controle , Adulto , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/epidemiologia , Dispositivos para Expansão de Tecidos , Resultado do TratamentoRESUMO
The low density lipoprotein receptor-related protein 1 (LRP1) is a ubiquitously expressed cell surface receptor that protects from intracellular cholesterol accumulation. However, the underlying mechanisms are unknown. Here we show that the extracellular (α) chain of LRP1 mediates TGFß-induced enhancement of Wnt5a, which limits intracellular cholesterol accumulation by inhibiting cholesterol biosynthesis and by promoting cholesterol export. Moreover, we demonstrate that the cytoplasmic (ß) chain of LRP1 suffices to limit cholesterol accumulation in LRP1(-/-) cells. Through binding of Erk2 to the second of its carboxyl-terminal NPXY motifs, LRP1 ß-chain positively regulates the expression of ATP binding cassette transporter A1 (ABCA1) and of neutral cholesterol ester hydrolase (NCEH1). These results highlight the unexpected functions of LRP1 and the canonical Wnt5a pathway and new therapeutic potential in cholesterol-associated disorders including cardiovascular diseases.
Assuntos
Colesterol/metabolismo , Receptores de LDL/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Via de Sinalização Wnt , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Sequência de Aminoácidos , Animais , Células HEK293 , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Receptores de LDL/química , Receptores de LDL/genética , Esterol Esterase/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5aRESUMO
A 59-year-old male, with a history of angiogram via the left radial artery during the workup for multi-trauma, presented to the hand clinic with a 14-day history of progressive critical ischemia in the left thumb and index finger, along with dry gangrene of the distal index fingertip. Radial artery occlusion was confirmed on imaging. The patient underwent radial artery thrombectomy, arterial reconstruction with vein graft, and amputation of the index fingertip. Postoperatively, perfusion to the thumb and index finger was restored, resulting in the resolution of associated pain and hypersensitivity. This case demonstrates the delayed presentation of ischemia following radial artery cannulation, which was successfully managed with radial artery thrombectomy and a saphenous vein graft.
RESUMO
Toxoplasma gondii motility, which is essential for host cell entry, migration through host tissues, and invasion, is a unique form of actin-dependent gliding. It is powered by a motor complex mainly composed of myosin heavy chain A, myosin light chain 1, gliding associated proteins GAP45, and GAP50, the only integral membrane anchor so far described. In the present study, we have combined glycomic and proteomic approaches to demonstrate that all three potential N-glycosylated sites of GAP50 are occupied by unusual N-glycan structures that are rarely found on mature mammalian glycoproteins. Using site-directed mutagenesis, we show that N-glycosylation is a prerequisite for GAP50 transport from the endoplasmic reticulum to the Golgi apparatus and for its subsequent delivery into the inner complex membrane. Assembly of key partners into the gliding complex, and parasite motility are severely impaired in the unglycosylated GAP50 mutants. Furthermore, comparative affinity purification using N-glycosylated and unglycosylated GAP50 as bait identified three novel hypothetical proteins including the recently described gliding associated protein GAP40, and we demonstrate that N-glycans are required for efficient binding to gliding partners. Collectively, these results provide the first detailed analyses of T. gondii N-glycosylation functions that are vital for parasite motility and host cell entry.
Assuntos
Movimento Celular , Retículo Endoplasmático/metabolismo , Glicoproteínas/química , Complexo de Golgi/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Motores Moleculares/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/metabolismo , Membrana Celular/genética , Membrana Celular/metabolismo , Movimento Celular/fisiologia , Fibroblastos/citologia , Fibroblastos/parasitologia , Glicômica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Interações Hospedeiro-Parasita/genética , Humanos , Espectrometria de Massas , Proteínas de Membrana/genética , Proteínas Motores Moleculares/genética , Mutagênese Sítio-Dirigida , Plasmídeos , Ligação Proteica , Transporte Proteico/fisiologia , Proteômica , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Toxoplasma/genética , TransfecçãoRESUMO
CASE: A 62-year-old woman presented with wrist pain secondary to a distal radius fracture malunion 4 months after a fall onto an outstretched hand. She was not an ideal candidate for osteotomy and bone graft because of the degree of displacement and osteoporosis, so after nonoperative treatment was unsuccessful, she was offered total wrist arthroplasty (TWA) or arthrodesis and opted for TWA. CONCLUSION: At 14-month follow-up, the patient reported significant improvement in her pain and function. The current generation of TWA implants may allow use in the management of symptomatic distal radius malunions in older, low-demand patients.
Assuntos
Artroplastia de Substituição , Rádio (Anatomia) , Feminino , Humanos , Idoso , Pessoa de Meia-Idade , Punho , Artralgia , DorRESUMO
BACKGROUND: Transitional care programs establish comprehensive outpatient care after hospitalization. This scoping review aimed to define participant characteristics and structure of transitional care programs for injured adults as well as associated readmission rates, cost of care, and follow-up adherence. METHODS: We conducted a scoping review in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews standard. Information sources searched were Medline, the Cochrane Library, CINAHL, and Scopus Plus with Full Text. Eligibility criteria were systematic reviews, clinical trials, and observational studies of transitional care programs for injured adults in the United States, published in English since 2000. Two independent reviewers screened all full texts. A data charting process extracted patient characteristics, program structure, readmission rates, cost of care, and follow-up adherence for each study. RESULTS: A total of 10 studies described 9 transitional care programs. Most programs (60%) were nurse/social-worker-led post-discharge phone call programs that provided follow-up reminders and inquired regarding patient concerns. The remaining 40% of programs were comprehensive interdisciplinary case-coordination transitional care programs. Readmissions were reduced by 5% and emergency department visits by 13% among participants of both types of programs compared to historic data. Both programs improved follow-up adherence by 75% compared to historic data. CONCLUSION: Transitional care programs targeted at injured patients vary in structure and may reduce overall health care use.
Assuntos
Cuidado Transicional , Adulto , Humanos , Alta do Paciente , Assistência ao Convalescente , Hospitalização , Assistência AmbulatorialRESUMO
Sterols are membrane-bound isoprenoid lipids that are required for cell viability and growth. In plants, it is generally assumed that 3-hydroxy-3-methylglutaryl-CoA-reductase (HMGR) is a key element of their biosynthesis, but the molecular regulation of that pathway is largely unknown. In an attempt to identify regulators of the biosynthetic flux from acyl-CoA toward phytosterols, we compared the membrane phosphoproteome of wild-type Arabidopsis thaliana and of a mutant being deficient in HMGR1. We performed a N-terminal labeling of microsomal peptides with a trimethoxyphenyl phosphonium (TMPP) derivative, followed by a quantitative assessment of phosphopeptides with a spectral counting method. TMPP derivatization of peptides resulted in an improved LC-MS/MS detection due to increased hydrophobicity in chromatography and ionization efficiency in electrospray. The phosphoproteome coverage was 40% higher with this methodology. We further found that 31 proteins were in a different phosphorylation state in the hmgr1-1 mutant as compared with the wild-type. One-third of these proteins were identified based on novel phosphopeptides. This approach revealed that phosphorylation changes in the Arabidopsis membrane proteome targets major cellular processes such as transports, calcium homeostasis, photomorphogenesis, and carbohydrate synthesis. A reformatting of these processes appears to be a response of a genetically reduced sterol biosynthesis.
Assuntos
Arabidopsis/metabolismo , Fosfoproteínas/análise , Fitosteróis/biossíntese , Proteoma/análise , Sequência de Aminoácidos , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/análise , Proteínas de Arabidopsis/metabolismo , Membrana Celular/química , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Microssomos/química , Microssomos/metabolismo , Dados de Sequência Molecular , Mutação , Fosfoproteínas/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteoma/metabolismo , Transdução de SinaisRESUMO
Ubiquitin-dependent processes can be antagonized by substrate-specific deubiquitination enzymes involved in many cellular functions. In this study, we show that the yeast Ubp3-Bre5 deubiquitination complex interacts with both the chaperone-like Cdc48, a major actor of the ubiquitin and proteasome system, and Ufd3, a ubiquitin-binding cofactor of Cdc48. We observed that these partners are required for the Ubp3-Bre5-dependent and starvation-induced selective degradation of yeast mature ribosomes, also called ribophagy. By contrast, proteasome-dependent degradation does not participate in this process. Our data favour the idea that these factors cooperate to recognize and deubiquitinate specific substrates of ribophagy before their vacuolar degradation.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenosina Trifosfatases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Endopeptidases/metabolismo , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenosina Trifosfatases/genética , Proteínas de Ciclo Celular/genética , Endopeptidases/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Ubiquitina/metabolismo , Proteína com ValosinaRESUMO
BACKGROUND: Despite multiple surgical modalities available for the management of Morton's neuroma, complications remain common. Targeted muscle reinnervation (TMR) has yet to be explored as an option for the prevention of recurrence of Morton's neuroma. The purpose of the present investigation was to determine the consistency of the relevant foot neurovascular and muscle anatomy and to demonstrate the feasibility of TMR as an option for Morton's neuroma. METHODS: The anatomy of 5 fresh-tissue donor cadaver feet was studied, including the course and location of the medial and lateral plantar nerves (MPNs and LPNs), motor branches to abductor hallucis (AH) and flexor digitorum brevis (FDB), as well as the course of sensory plantar digital nerves. Measurements for the locations of the muscular and sensory branches were taken relative to landmarks including the navicular tuberosity (NT), AH, FDB, and the third metatarsophalangeal joint (third MTPJ). RESULTS: The mean number of nerve branches to FDB identified was 2. These branch points occurred at an average of 8.6 cm down the MPN or LPN, 9.0 cm from the third MTPJ, 3.0 cm distal to AH distal edge, and 4.8 cm from the NT. The mean number of nerves to AH was 2.2. These branch points occurred at an average of 6.3 cm down the MPN, 11.9 cm from the third MTPJ, 0.8 cm from the AH distal edge, and 3.8 cm from the NT. CONCLUSIONS: Recurrent interdigital neuroma, painful scar, and neuropathic pain are common complications of operative management for Morton's neuroma. Targeted muscle reinnervation is a technique that has demonstrated efficacy for the prevention and treatment of neuroma, neuropathic pain, and phantom limb pain in amputees. Herein, we have described the neuromuscular anatomy for the application of TMR for the management of Morton's neuroma. Target muscles, including the AH and FDB, have consistent innervation patterns in the foot, and consequently, TMR represents a viable option to consider for the management of recalcitrant Morton's neuroma. LEVELS OF EVIDENCE: V.
Assuntos
Doenças do Pé , Neuroma Intermetatársico , Neuroma , Estudos de Viabilidade , Pé , Humanos , Músculos , Neuroma/cirurgiaRESUMO
Acid mine drainage of the Carnoulès mine (France) is characterized by acid waters containing high concentrations of arsenic and iron. In the first 30 m along the Reigous, a small creek draining the site, more than 38% of the dissolved arsenic was removed by co-precipitation with Fe(III), in agreement with previous studies, which suggest a role of microbial activities in the co-precipitation of As(III) and As(V) with Fe(III) and sulfate. To investigate how this particular ecosystem functions, the bacterial community was characterized in water and sediments by 16S rRNA encoding gene library analysis. Based on the results obtained using a metaproteomic approach on sediments combined with high-sensitivity HPLC-chip spectrometry, several GroEL orthologs expressed by the community were characterized, and the active members of the prokaryotic community inhabiting the creek sediments were identified. Many of these bacteria are ß-proteobacteria such as Gallionella and Thiomonas, but γ-proteobacteria such as Acidithiobacillus ferrooxidans and α-proteobacteria such as Acidiphilium, Actinobacteria, and Firmicutes were also detected.
Assuntos
Arsênio/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Arsênio/análise , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Sedimentos Geológicos/química , Dados de Sequência Molecular , FilogeniaRESUMO
Aromatic compounds comprise a large class of natural and man-made compounds, many of which are of considerable concern for the environment and human health. In aromatic compound-degrading anaerobic bacteria the central intermediate of aromatic catabolism, benzoyl coenzyme A, is attacked by dearomatizing benzoyl-CoA reductases (BCRs). An ATP-dependent BCR has been characterized in facultative anaerobes. In contrast, a previous analysis of the soluble proteome from the obligately anaerobic model organism Geobacter metallireducens identified genes putatively coding for a completely different dearomatizing BCR. The corresponding BamBCDEFGHI complex is predicted to comprise soluble molybdenum or tungsten, selenocysteine, and FeS cluster-containing components. To elucidate key processes involved in the degradation of aromatic compounds in obligately anaerobic bacteria, differential membrane protein abundance levels from G. metallireducens grown on benzoate and acetate were determined by the MS-based spectral counting approach. A total of 931 proteins were identified by combining one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with liquid chromatography-tandem mass spectrometry. Several membrane-associated proteins involved in the degradation of aromatic compounds were newly identified including proteins with similarities to modules of NiFe/heme b-containing and energy-converting hydrogenases, cytochrome bd oxidases, dissimilatory nitrate reductases, and a tungstate ATP-binding cassette transporter system. The transcriptional regulation of differentially expressed genes was analyzed by quantitative reverse transcription-PCR; in addition benzoate-induced in vitro activities of hydrogenase and nitrate reductase were determined. The results obtained provide novel insights into the poorly understood degradation of aromatic compounds in obligately anaerobic bacteria.