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1.
Nucleic Acids Res ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38811035

RESUMO

Ribosomes trapped on mRNAs during protein synthesis need to be rescued for the cell to survive. The most ubiquitous bacterial ribosome rescue pathway is trans-translation mediated by tmRNA and SmpB. Genetic inactivation of trans-translation can be lethal, unless ribosomes are rescued by ArfA or ArfB alternative rescue factors or the ribosome-associated quality control (RQC) system, which in Bacillus subtilis involves MutS2, RqcH, RqcP and Pth. Using transposon sequencing in a trans-translation-incompetent B. subtilis strain we identify a poorly characterized S4-domain-containing protein YlmH as a novel potential RQC factor. Cryo-EM structures reveal that YlmH binds peptidyl-tRNA-50S complexes in a position analogous to that of S4-domain-containing protein RqcP, and that, similarly to RqcP, YlmH can co-habit with RqcH. Consistently, we show that YlmH can assume the role of RqcP in RQC by facilitating the addition of poly-alanine tails to truncated nascent polypeptides. While in B. subtilis the function of YlmH is redundant with RqcP, our taxonomic analysis reveals that in multiple bacterial phyla RqcP is absent, while YlmH and RqcH are present, suggesting that in these species YlmH plays a central role in the RQC.

2.
Sci Rep ; 14(1): 6082, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480759

RESUMO

Melanoma response to immune-modulating therapy remains incompletely characterized at the molecular level. In this study, we assess melanoma immunotherapy response using a multi-scale network approach to identify gene modules with coordinated gene expression in response to treatment. Using gene expression data of melanoma before and after treatment with nivolumab, we modeled gene expression changes in a correlation network and measured a key network geometric property, dynamic Ollivier-Ricci curvature, to distinguish critical edges within the network and reveal multi-scale treatment-response gene communities. Analysis identified six distinct gene modules corresponding to sets of genes interacting in response to immunotherapy. One module alone, overlapping with the nuclear factor kappa-B pathway (NFkB), was associated with improved patient survival and a positive clinical response to immunotherapy. This analysis demonstrates the usefulness of dynamic Ollivier-Ricci curvature as a general method for identifying information-sharing gene modules in cancer.


Assuntos
Melanoma , Humanos , Melanoma/genética , Melanoma/terapia , Redes Reguladoras de Genes , Imunoterapia
3.
EMBO J ; 43(4): 484-506, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177497

RESUMO

Stalled ribosomes are rescued by pathways that recycle the ribosome and target the nascent polypeptide for degradation. In E. coli, these pathways are triggered by ribosome collisions through the recruitment of SmrB, a nuclease that cleaves the mRNA. In B. subtilis, the related protein MutS2 was recently implicated in ribosome rescue. Here we show that MutS2 is recruited to collisions by its SMR and KOW domains, and we reveal the interaction of these domains with collided ribosomes by cryo-EM. Using a combination of in vivo and in vitro approaches, we show that MutS2 uses its ABC ATPase activity to split ribosomes, targeting the nascent peptide for degradation through the ribosome quality control pathway. However, unlike SmrB, which cleaves mRNA in E. coli, we see no evidence that MutS2 mediates mRNA cleavage or promotes ribosome rescue by tmRNA. These findings clarify the biochemical and cellular roles of MutS2 in ribosome rescue in B. subtilis and raise questions about how these pathways function differently in diverse bacteria.


Assuntos
Bacillus subtilis , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ribossomos/metabolismo , Peptídeos/metabolismo
4.
Sci Rep ; 14(1): 488, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177639

RESUMO

Network properties account for the complex relationship between genes, making it easier to identify complex patterns in their interactions. In this work, we leveraged these network properties for dual purposes. First, we clustered pediatric sarcoma tumors using network information flow as a similarity metric, computed by the Wasserstein distance. We demonstrate that this approach yields the best concordance with histological subtypes, validated against three state-of-the-art methods. Second, to identify molecular targets that would be missed by more conventional methods of analysis, we applied a novel unsupervised method to cluster gene interactomes represented as networks in pediatric sarcoma. RNA-Seq data were mapped to protein-level interactomes to construct weighted networks that were then subjected to a non-Euclidean, multi-scale geometric approach centered on a discrete notion of curvature. This provides a measure of the functional association among genes in the context of their connectivity. In confirmation of the validity of this method, hierarchical clustering revealed the characteristic EWSR1-FLI1 fusion in Ewing sarcoma. Furthermore, assessing the effects of in silico edge perturbations and simulated gene knockouts as quantified by changes in curvature, we found non-trivial gene associations not previously identified.


Assuntos
Sarcoma de Ewing , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Criança , Proteínas de Fusão Oncogênica/genética , Sarcoma/genética , Sarcoma de Ewing/patologia , Proteína EWS de Ligação a RNA/metabolismo , Neoplasias de Tecidos Moles/genética , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteína Proto-Oncogênica c-fli-1/genética , Linhagem Celular Tumoral
5.
JOR Spine ; 7(1): e1291, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38222805

RESUMO

Background: Lumbar spine pathology (LSP) is a common source of low back or leg pain, and paraspinal muscle in these patients demonstrates fatty and fibrotic infiltration, and cellular degeneration that do not reverse with exercise-based rehabilitation. However, it is unclear of this lack of response is due to insufficient exercise stimulus, or an inability to mount a growth response. The purpose of this study was to compare paraspinal muscle gene expression between individuals with LSP who do and do not undergo an acute bout of resistance exercise. Methods: Paraspinal muscle biopsies were obtained from 64 individuals with LSP undergoing spinal surgery. Eight participants performed an acute bout of machine-based lumbar extension resistance exercise preoperatively. Gene expression for 42 genes associated with adipogenic/metabolic, atrophic, fibrogenic, inflammatory, and myogenic pathways was measured, and differential expression between exercised and non-exercised groups was evaluated for (a) the full cohort, and (b) an age, gender, acuity, and etiology matched sub-cohort. Principal components analyses were used to identify gene expression clustering across clinical phenotypes. Results: The exercised cohort demonstrated upregulation of inflammatory gene IL1B, inhibition of extracellular matrix components (increased MMP3&9, decreased TIMP1&3, COL1A1) and metabolic/adipogenic genes (FABP4, PPARD, WNT10B), and downregulation of myogenic (MYOD, ANKRD2B) and atrophic (FOXO3) genes compared to the non-exercised cohort, with similar patterns in the matched sub-analysis. There were no clinical phenotypes significantly associated with gene expression profiles. Conclusion: An acute bout of moderate-high intensity resistance exercise did not result in upregulation of myogenic genes in individuals with LSP. The response was characterized by mixed metabolic and fibrotic gene expression, upregulation of inflammation, and downregulation of myogenesis.

6.
bioRxiv ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-37090606

RESUMO

Cancer transcriptional patterns exhibit both shared and unique features across diverse cancer types, but whether these patterns are sufficient to characterize the full breadth of tumor phenotype heterogeneity remains an open question. We hypothesized that cancer transcriptional diversity mirrors patterns in normal tissues optimized for distinct functional tasks. Starting with normal tissue transcriptomic profiles, we use non-negative matrix factorization to derive six distinct transcriptomic phenotypes, called archetypes, which combine to describe both normal tissue patterns and variations across a broad spectrum of malignancies. We show that differential enrichment of these signatures correlates with key tumor characteristics, including overall patient survival and drug sensitivity, independent of clinically actionable DNA alterations. Additionally, we show that in HR+/HER2-breast cancers, metastatic tumors adopt transcriptomic signatures consistent with the invaded tissue. Broadly, our findings suggest that cancer often arrogates normal tissue transcriptomic characteristics as a component of both malignant progression and drug response. This quantitative framework provides a strategy for connecting the diversity of cancer phenotypes and could potentially help manage individual patients.

7.
Burns ; 50(2): 424-432, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38087659

RESUMO

BACKGROUND: StrataGraft® (allogeneic cultured keratinocytes and dermal fibroblasts in murine collagen-dsat) is an FDA-approved viable bioengineered allogeneic cellularized construct for adult patients with deep partial-thickness burns requiring surgery. We characterized the structural and functional properties of StrataGraft to improve product understanding by evaluating extracellular matrix (ECM) molecule distribution and secreted protein factor expression in vitro. METHODS: ECM protein expression was determined using indirect immunofluorescence on construct cross sections using commercial antibodies against collagen III, IV, VI, laminin-332, and decorin. Human collagen I expression was verified by enzyme-linked immunosorbent assay (ELISA) for collagen I C-terminal propeptide. Soluble protein factor secretion was quantified by multiplex biomarker assays and singleplex ELISA in conditioned media from meshed constructs. RESULTS: StrataGraft cellular components produced collagen I, collagen III, collagen VI, and decorin in patterns indicating an organized ECM. Distributions of collagen IV and laminin-332 indicated formation of basement membranes and dermal-epidermal junctions. Soluble protein factors were observed in the pg/cm2/h range from 1 h to the experiment end at 168 h. CONCLUSIONS: The organization of the ECM proteins was like human skin and the viable cellular components provided sustained secretion of soluble wound healing factors, making StrataGraft an attractive option for treating severe burns.


Assuntos
Queimaduras , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Animais , Camundongos , Proteínas da Matriz Extracelular , Decorina , Queimaduras/terapia , Cicatrização , Matriz Extracelular , Colágeno Tipo I , Calinina , Fibroblastos
8.
bioRxiv ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38045365

RESUMO

Melanoma response to immune-modulating therapy remains incompletely characterized at the molecular level. In this study, we assess melanoma immunotherapy response using a multi-scale network approach to identify gene modules with coordinated gene expression in response to treatment. Using gene expression data of melanoma before and after treatment with nivolumab, we modeled gene expression changes in a correlation network and measured a key network geometric property, dynamic Ollivier-Ricci curvature, to distinguish critical edges within the network and reveal multi-scale treatment-response gene communities. Analysis identified six distinct gene modules corresponding to sets of genes interacting in response to immunotherapy. One module alone, overlapping with the nuclear factor kappa-B pathway (NFKB), was associated with improved patient survival and a positive clinical response to immunotherapy. This analysis demonstrates the usefulness of dynamic Ollivier-Ricci curvature as a general method for identifying information-sharing gene modules in cancer.

9.
Mol Cell ; 83(23): 4290-4303.e9, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37951216

RESUMO

Reactive aldehydes are abundant endogenous metabolites that challenge homeostasis by crosslinking cellular macromolecules. Aldehyde-induced DNA damage requires repair to prevent cancer and premature aging, but it is unknown whether cells also possess mechanisms that resolve aldehyde-induced RNA lesions. Here, we establish photoactivatable ribonucleoside-enhanced crosslinking (PAR-CL) as a model system to study RNA crosslinking damage in the absence of confounding DNA damage in human cells. We find that such RNA damage causes translation stress by stalling elongating ribosomes, which leads to collisions with trailing ribosomes and activation of multiple stress response pathways. Moreover, we discovered a translation-coupled quality control mechanism that resolves covalent RNA-protein crosslinks. Collisions between translating ribosomes and crosslinked mRNA-binding proteins trigger their modification with atypical K6- and K48-linked ubiquitin chains. Ubiquitylation requires the E3 ligase RNF14 and leads to proteasomal degradation of the protein adduct. Our findings identify RNA lesion-induced translational stress as a central component of crosslinking damage.


Assuntos
RNA , Ubiquitina , Humanos , RNA/metabolismo , Ubiquitinação , Ubiquitina/metabolismo , Ribossomos/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Aldeídos , Biossíntese de Proteínas
10.
JOR Spine ; 6(3): e1266, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37780825

RESUMO

Purpose: Previous research has demonstrated increased stiffness in the multifidus muscle compared to other paraspinal muscles at the fiber bundle level. We aimed to compare single fiber and fiber bundle passive mechanical properties of multifidus muscle: (1) in 40 patients undergoing primary versus revision surgery and (2) in muscle with mild versus severe fatty infiltration. Methods: The degree of muscle fatty infiltration was graded using the patients' spine magnetic resonance images. Average single fiber and fiber bundle passive mechanical properties across three tests were compared between primary (N = 30) and revision (N = 10) surgery status, between mild and severe fatty infiltration levels, between sexes, and with age from passive stress-strain tests of excised multifidus muscle intraoperative biopsies. Results: At the single fiber level, elastic modulus was unaffected by degree of fatty infiltration or surgery status. Female sex (p = 0.001) and younger age (p = 0.04) were associated with lower multifidus fiber elastic modulus. At the fiber bundle level, which includes connective tissue around fibers, severe fatty infiltration (p = 0.01) and younger age (p = 0.06) were associated with lower elastic modulus. Primary surgery also demonstrated a moderate, but non-significant effect for lower elastic modulus (p = 0.10). Conclusions: Our results demonstrate that female sex is the primary driver for reduced single fiber elastic modulus of the multifidus, while severity of fatty infiltration is the primary driver for reduced elastic modulus at the level of the fiber bundle in individuals with lumbar spine pathology.

11.
Cancer Genet ; 276-277: 43-47, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37480761

RESUMO

Myeloid/lymphoid neoplasm with fibroblast growth factor 1 rearrangements (MLN-FGFR1) represents a rare group of hematologic neoplasms, with approximately 100 cases reported to date. A 69-year-old woman with a history of polycythemia and leukocytosis, with negative molecular testing for JAK2, CALR, and MPL, presented with diffuse adenopathy. A lymph node (LN) biopsy revealed effacement by T-lymphoblasts, consistent with T-cell acute lymphoblastic lymphoma (T-ALL). A staging bone marrow (BM) biopsy demonstrated trilineage hyperplasia, which, taken together with the patient's elevated hemoglobin and low serum erythropoietin level, fulfilled diagnostic criteria for polycythemia vera. Karyotype and fluorescence in situ hybridization on both the BM and LN demonstrated a FGFR1 rearrangement due to t(8;13), consistent with MLN-FGFR1. Whole genome sequencing on the LN additionally identified a pathogenic frameshift mutation of ASXL1 NC_000020.11:g32434646dup NM_015338.6(ASXL1):c.1934dup p.(Gly646Trpfs) predicted to result in loss of protein function, a finding also observed in 8.1% of BM reads. Both the BM and LN harbored missense variants in HDAC4 NM_001378414.1(HDAC4):c.[2763G>A]; [2763=] p.(Met921Ile) and CHEK2 NM_007194.4(CHEK2):c.[538C>T];[538=] p.(Arg180Cys), with an unknown significance. Despite initial response to Mini-CVD + venetoclax, the patient subsequently experienced rapid clinical deterioration and death. We report the second case of MLN-FGFR1 with an ASXL1 mutation and the first case with HDAC4 and CHEK2 variants.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Leucemia-Linfoma Linfoblástico de Células Precursoras , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Feminino , Humanos , Idoso , Policitemia Vera/genética , Hibridização in Situ Fluorescente , Transtornos Mieloproliferativos/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética
12.
J Trauma Acute Care Surg ; 95(5): 672-678, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37478341

RESUMO

BACKGROUND: Uncontrolled hemorrhage is the leading cause of preventable death in combat and civilian trauma. Efficacious hemostatic agents in junctional hemorrhage can quell blood loss and improve survival. We hypothesized that a novel hemostatic foam of starch and chitosan would improve hemostasis, and thereby increase survival in a swine femoral artery hemorrhage model when compared with CombatGauze (CG). METHODS: A novel hemostatic foam of starch and chitosan was created and modified during the study period. Thirty pigs (four excluded) were assigned to treatment using either foam version 1 (FV1, n = 9) or 2 (FV2, n = 8), or (n = 9) in a standard swine femoral artery hemorrhage model. Animals were observed for 150 minutes. Outcomes assessed included hemostasis, survival, posttreatment blood loss, IV fluid volume, and hemodynamic and laboratory trends. RESULTS: Hemostasis prior to 150 minutes was similar with 44.4%, 77.8%, and 50% of swine treated with CG, FV1 and FV2, respectively (Kaplan-Meyer and log-rank test [KM-LR] p > 0.05). Survival to 150 minutes was improved in swine treated with FV1 (100%) compared with CG (55.6%) (KM-LR p = 0.02). Survival was similar between FV1 and FV2 (75%) (KM-LR p > 0.05), and between CG and FV2 (KM-LR p > 0.05). Using mixed model for longitudinal data, mean arterial pressure decreased significantly in CG- and FV2-treated swine, while there was no significant change in mean arterial pressure in FV1-treated swine. Trends in lactic acid, hematocrit, platelets, INR, and thrombelastography were more favorable for FV1 compared with CG. CONCLUSION: In this preclinical study of junctional hemorrhage, survival was improved in swine treated with version 1 of a novel chitosan/starch foam compared with CG. Trends in hemodynamics and laboratory data were also more favorable in the FV1-treated swine. This novel hemostatic foam may be an effective alternative to current hemostatic agents.


Assuntos
Quitosana , Hemostáticos , Suínos , Animais , Hemostáticos/farmacologia , Hemostáticos/uso terapêutico , Artéria Femoral/lesões , Polieletrólitos , Hemorragia/etiologia , Hemostasia , Amido
13.
Data Brief ; 48: 109144, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383763

RESUMO

Postoperative opioid prescribing has historically lacked information critical to balancing the pain control needs of the individual patient with our professional responsibility to judiciously prescribe these high-risk medications. This data evaluates pain control, satisfaction with pain control, and opioid utilization among patients undergoing isolated mid-urethral sling (MUS) randomized to one of two different opioid prescribing regimens. This study was registered on clinicaltrials.gov (NCT04277975). Women undergoing isolated MUS by a Female Pelvic Medicine and Reconstructive Surgery physician at a Penn State Health hospital from June 1, 2020 to November 22, 2021 were offered enrollment into this prospective, randomized, open-label, non-inferiority clinical trial. Participants gave informed consent and were enrolled by a member of the study team. Allocation was concealed to patient and study personnel until randomization on the day of surgery. Preoperatively, all participants completed baseline demographic and pain surveys including CSI-9, PCS, and Likert pain score (scale 0-10). Participants were randomized to either receive a standard prescription of ten 5 mg tablets oxycodone provided preoperatively (standard) or opioid prescription provided only upon patient request postoperatively (restricted). Randomization was performed by the study team surgeon using the REDCap randomization module on the day of surgery. Following MUS, subjects completed a daily diary for 1 week, i.e., postoperative day (POD) 0 through 7. Within the dairy, subjects provided the following information: average daily pain score, opioid use and amount of opioid utilized, other forms of pain management, satisfaction with pain control, perception of the amount of opioid prescribed, and need for pain management hospital/clinic visits. The online Prescription Drug Monitoring Program (PDMP) was queried for all patients to determine if prescriptions for opioids were filled during the postoperative period. The primary outcome was average postoperative day 1 pain score and an a priori determined margin of non-inferiority was set at 2 points. Secondary outcomes included whether subject filled an opioid prescription (indicated by the online PDMP), opioid use (yes/no), satisfaction with pain control (on a scale of 1= "much worse" to 5= "much better" than expected), and how subjects felt about the amount of opioid prescribed (on a scale of 1="prescribed far more" to 3="prescribed the right amount" to 5="prescribed far less" opioid than needed). 82 participants underwent isolated MUS placement and met inclusion criteria; 40 were randomized to the standard arm and 42 to the restricted group. Within this manuscript, we detail the data obtained from this randomized clinical trial and the methods utilized.

14.
Plant Mol Biol ; 112(4-5): 279-291, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37326800

RESUMO

A long-held goal of synthetic biology has been the transfer of a bacterial nitrogen-fixation pathway into plants to reduce the use of chemical fertiliser on crops such as rice, wheat and maize. There are three classes of bacterial nitrogenase, named after their metal requirements, containing either a MoFe-, VFe- or FeFe-cofactor, that converts N2 gas to ammonia. Relative to the Mo-nitrogenase the Fe-nitrogenase is not as efficient for catalysis but has less complex genetic and metallocluster requirements, features that may be preferable for engineering into crops. Here we report the successful targeting of bacterial Fe-nitrogenase proteins, AnfD, AnfK, AnfG and AnfH, to plant mitochondria. When expressed as a single protein AnfD was mostly insoluble in plant mitochondria, but coexpression of AnfD with AnfK improved its solubility. Using affinity-based purification of mitochondrially expressed AnfK or AnfG we were able to demonstrate a strong interaction of AnfD with AnfK and a weaker interaction of AnfG with AnfDK. This work establishes that the structural components of the Fe-nitrogenase can be engineered into plant mitochondria and form a complex, which will be a requirement for function. This report outlines the first use of Fe-nitrogenase proteins within a plant as a preliminary step towards engineering an alternative nitrogenase into crops.


Assuntos
Azotobacter vinelandii , Nitrogenase , Nitrogenase/genética , Nitrogenase/metabolismo , Azotobacter vinelandii/genética , Azotobacter vinelandii/metabolismo , Ferro , Fixação de Nitrogênio , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
15.
Cureus ; 15(6): e40195, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37325689

RESUMO

BACKGROUND: Reherniation rates following lumbar discectomy are low for most patients; however, patients with a large defect in the annulus fibrosis have a significantly higher risk of recurrence. Previous results from a randomized controlled trial (RCT) demonstrated that the implantation of a bone-anchored annular closure device (ACD) during discectomy surgery lowered the risk of symptomatic reherniation and reoperation over one year with fewer serious adverse events (SAEs) compared to discectomy alone. OBJECTIVE: The objective of this prospective, post-market, historically controlled study was to evaluate the use of an ACD during discectomy, and to confirm the results of the RCT that was used to establish regulatory approval in the United States. METHODS: In this post-market study, all patients (N = 55) received discectomy surgery with a bone-anchored ACD. The comparison population was patients enrolled in the RCT study who had discectomy with an ACD (N = 262) or discectomy alone (N = 272). All other eligibility criteria, surgical technique, device characteristics, and follow-up methodology were comparable between studies. Endpoints included rate of symptomatic reherniation or reoperation, SAEs, and patient-reported measures of disability, pain, and quality of life. RESULTS: Fifty-five patients received ACD implants at 12 sites between May 2020 and February 2021. In the previous RCT, 272 control patients had discectomy surgery alone (RCT-Control), and 262 patients had discectomy surgery with an ACD implant (RCT-ACD). Baseline characteristics across groups were typical of the overall population undergoing lumbar discectomy. The proportion of patients who experienced reherniation and/or reoperation was significantly lower in the ACD group compared to RCT-ACD and RCT-Control groups (p < 0.05). In the ACD study, the one-year rate of symptomatic reherniation was 3.7%, compared to 8.5% in the RCT-ACD group and 17.0% in the RCT-Control group. In the ACD group, the risk of reoperation was 5.5%, compared to 6.5% in the RCT-ACD group and 12.5% in the RCT-Control group. There were no device-related SAEs or device integrity failures in the ACD, and there were clinically meaningful improvements in patient-reported measures of disability, pain, and quality of life. CONCLUSION: In this post-market study of bone-anchored ACD in patients with large annular defects, rates of symptomatic reherniation, reoperation, and SAEs were all low. Compared to the RCT, the post-market ACD study demonstrated lower rates of reherniation and/or reoperation and measures of back pain one-year post-surgery.

16.
Clin Imaging ; 100: 48-53, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37207442

RESUMO

PURPOSE: To investigate whether pre-procedure Computed Tomography Angiography (CTA) improves radiation exposure, procedure complexity, and symptom recurrence after bronchial embolization for massive hemoptysis. MATERIAL AND METHODS: A single-center retrospective review of bronchial artery embolization (BAE) for massive hemoptysis was performed for procedures between 2008 and 2019. Multi-variate analysis was performed to determine the significance of pre-procedure CTA and etiology of hemoptysis on patient radiation exposure (reference point air kerma, RPAK) and rate of recurrent hemoptysis. RESULTS: There were 61 patients (mean age 52.5 years; SD = 19.2 years, and 57.3% male) and CTA was obtained for 42.6% (26/61). Number of vessels selected was a mean of 7.2 (SD = 3.4) in those without CTA and 7.4 (SD = 3.4) in those with CTA (p = 0.923). Mean procedure duration was 1.8 h (SD = 1.6 h) in those without CTA and 1.3 h (SD = 1.0 h) in those with CTA (p = 0.466). Mean fluoroscopy time and RPAK per procedure were 34.9 min (SD = 21.5 min) and 1091.7 mGy (SD = 1316.6 mGy) for those without a CTA and 30.7 min (SD = 30.7 min) and 771.5 mGy (SD = 590.0 mGy) for those with a CTA (p = 0.523, and p = 0.879, respectively). Mean total iodine given was 49.2 g (SD = 31.9 g) for those without a CTA and 70.6 g (SD = 24.9 g) for those with a CTA (p = 0.001). Ongoing hemoptysis at last clinical follow up was 13/35 (37.1%) in those without CTA and 9/26 (34.6%) in those with CTA (p = 0.794). CONCLUSIONS: Pre-procedure CTA did not improve radiation effective dose and symptom recurrence after BAE and is associated with significant increases in total iodine dose.


Assuntos
Embolização Terapêutica , Hemoptise , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Hemoptise/diagnóstico , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada por Raios X/efeitos adversos , Angiografia/efeitos adversos , Artérias Brônquicas/diagnóstico por imagem , Embolização Terapêutica/métodos , Estudos Retrospectivos , Doses de Radiação , Resultado do Tratamento
17.
bioRxiv ; 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37205477

RESUMO

Stalled ribosomes are rescued by pathways that recycle the ribosome and target the nascent polypeptide for degradation. In E. coli, these pathways are triggered by ribosome collisions through recruitment of SmrB, a nuclease that cleaves the mRNA. In B. subtilis, the related protein MutS2 was recently implicated in ribosome rescue. Here we show that MutS2 is recruited to collisions by its SMR and KOW domains and reveal the interaction of these domains with collided ribosomes by cryo-EM. Using a combination of in vivo and in vitro approaches, we show that MutS2 uses its ABC ATPase activity to split ribosomes, targeting the nascent peptide for degradation by the ribosome quality control pathway. Notably, we see no evidence of mRNA cleavage by MutS2, nor does it promote ribosome rescue by tmRNA as SmrB cleavage does in E. coli. These findings clarify the biochemical and cellular roles of MutS2 in ribosome rescue in B. subtilis and raise questions about how these pathways function differently in various bacteria.

18.
F S Rep ; 4(1): 121-126, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36959970

RESUMO

Objective: To determine the feasibility, safety, and outcomes of an oil-based, iodinated contrast using office-based, ultrasound-imaged hysterosalpingography in women with infertility. Design: Randomized Controlled Double Blind Clinical Trial. Setting: Academic health center. Interventions: Tubal flushing with oil-based contrast medium (Lipiodol UF) versus saline. Main Outcome Measures: Ongoing pregnancy rate, pain, quality of life, and thyroid function. Results: Forty-eight patients (24 in each group) were analyzed. The groups were well-matched at baseline. Ongoing pregnancy was noted in 17% (4/24) of the oil-contrast group versus 37% (9/24) in the saline group. Saline group patients more frequently initiated infertility therapy in the six-month follow-up period (saline, 67% vs. oil, 33%), and no serious adverse events in either group. There were no differences in pain from the procedure between groups. There were no differences in thyroid function tests postprocedure between groups, but within the oil-contrast group, there was a slight increase in thyroid-stimulating hormone (post vs. preratio of geometric means: 1.18; 95% confidence interval [CI], 1.02-1.38) and decrease in Free T4 (postdifference vs. predifference in means: 0.08 ng/dL; 95% CI, -0.14 to -0.01). Immediately after the test, the physicians correctly guessed 79% of oil and 71% of saline randomization assignments, whereas patients correctly guessed 63% of oil and 38% of saline. Conclusions: This pilot study demonstrates the safety and feasibility of giving an oil-based contrast medium during ultrasound-imaged hysterosalpingography. Pregnancies were seen after oil-based administration, and this contrast is associated with minor thyroid function impairment.

19.
Eur Spine J ; 32(4): 1123-1131, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36740606

RESUMO

PURPOSE: The purpose of this study was to understand potential baseline transcriptional expression differences in paraspinal skeletal muscle from patients with different underlying lumbar pathologies by comparing multifidus gene expression profiles across individuals with either disc herniation, facet arthropathy, or degenerative spondylolisthesis. METHODS: Multifidus biopsies were obtained from patients (n = 44) undergoing lumbar surgery for either disc herniation, facet arthropathy, or degenerative spondylolisthesis. Diagnostic categories were based on magnetic resonance images, radiology reports, and intraoperative reports. Gene expression for 42 genes was analysed using qPCR. A one-way analysis of variance was performed for each gene to determine differences in expression across diagnostic groups. Corrections for multiple comparisons across genes (Benjamini-Hochberg) and for between-group post hoc comparisons (Sidak) were applied. RESULTS: Adipogenic gene (ADIPOQ) expression was higher in the disc herniation group when compared to the facet arthropathy group (p = 0.032). Adipogenic gene (PPARD) expression was higher in the degenerative spondylolisthesis group when compared to the disc herniation group (p = 0.013), although absolute gene expression levels for all groups was low. Fibrogenic gene (COL3A1) had significantly higher expression in the disc herniation group and facet arthropathy group when compared to the degenerative spondylolisthesis group (p < 0.001 and p = 0.038, respectively). When adjusted for multiple comparisons, only COL3A1 remained significant (p = 0.012). CONCLUSION: Individuals with disc herniation and facet arthropathy demonstrate higher COL3A1 gene expression compared to those with degenerative spondylolisthesis. Future research is required to further understand the biological relevance of these transcriptional differences.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Artropatias , Espondilolistese , Humanos , Deslocamento do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/complicações , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/cirurgia , Espondilolistese/diagnóstico por imagem , Espondilolistese/genética , Espondilolistese/cirurgia , Músculos Paraespinais/diagnóstico por imagem , Músculos Paraespinais/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/efeitos adversos , Expressão Gênica
20.
J Bacteriol ; 205(2): e0037022, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36651772

RESUMO

The universally conserved protein elongation factor P (EF-P) facilitates translation at amino acids that form peptide bonds with low efficiency, particularly polyproline tracts. Despite its wide conservation, it is not essential in most bacteria and its physiological role remains unclear. Here, we show that EF-P affects the process of sporulation initiation in the bacterium Bacillus subtilis. We observe that the lack of EF-P delays expression of sporulation-specific genes. Using ribosome profiling, we observe that expression of spo0A, encoding a transcription factor that functions as the master regulator of sporulation, is lower in a Δefp strain than the wild type. Ectopic expression of Spo0A rescues the sporulation initiation phenotype, indicating that reduced spo0A expression explains the sporulation defect in Δefp cells. Since Spo0A is the earliest sporulation transcription factor, these data suggest that sporulation initiation can be delayed when protein synthesis is impaired. IMPORTANCE Elongation factor P (EF-P) is a universally conserved translation factor that prevents ribosome stalling at amino acids that form peptide bonds with low efficiency, particularly polyproline tracts. Phenotypes associated with EF-P deletion are pleiotropic, and the mechanistic basis underlying many of these phenotypes is unclear. Here, we show that the absence of EF-P affects the ability of B. subtilis to initiate sporulation by preventing normal expression of Spo0A, the key transcriptional regulator of this process. These data illustrate a mechanism that accounts for the sporulation delay and further suggest that cells are capable of sensing translation stress before committing to sporulation.


Assuntos
Proteínas de Bactérias , Fatores de Transcrição , Proteínas de Bactérias/genética , Fatores de Transcrição/metabolismo , Fatores de Alongamento de Peptídeos/genética , Aminoácidos/metabolismo , Esporos Bacterianos/genética , Bacillus subtilis/genética , Regulação Bacteriana da Expressão Gênica
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