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1.
Nature ; 602(7898): 664-670, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35016195

RESUMO

The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Deriva e Deslocamento Antigênicos/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , Testes de Neutralização , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Deriva e Deslocamento Antigênicos/genética , Vacinas contra COVID-19/imunologia , Linhagem Celular , Convalescença , Epitopos de Linfócito B/imunologia , Humanos , Evasão da Resposta Imune , Camundongos , SARS-CoV-2/química , SARS-CoV-2/classificação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Vesiculovirus/genética
2.
PLoS Pathog ; 18(8): e1010726, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36044447

RESUMO

Although combination antiretroviral therapy (ART) blocks HIV replication, it is not curative because infected CD4+ T cells that carry intact, infectious proviruses persist. Understanding the behavior of clones of infected T cells is important for understanding the stability of the reservoir; however, the stabilities of clones of infected T cells in persons on long-term ART are not well defined. We determined the relative stabilities of clones of infected and uninfected CD4+ T cells over time intervals of one to four years in three individuals who had been on ART for 9-19 years. The largest clones of uninfected T cells were larger than the largest clones of infected T cells. Clones of infected CD4+ T cells were more stable than clones of uninfected CD4+ T cells of a similar size. Individual clones of CD4+ T cells carrying intact, infectious proviruses can expand, contract, or remain stable over time.


Assuntos
Infecções por HIV , HIV-1 , Linfócitos T CD4-Positivos , Células Clonais , DNA Viral , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Provírus/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-38754723

RESUMO

OBJECTIVE: The aim of this study was to compare the efficacy of different endovascular revascularisation procedures for treating chronic limb threatening ischaemia (CLTI) using network meta-analysis (NMA). DATA SOURCES: The databases PubMed and Cochrane Central Register for Controlled Trials were searched on 14 March 2023. REVIEW METHODS: A NMA of randomised controlled trials (RCTs) reporting the efficacy of different endovascular revascularisation techniques for treating CLTI was performed according to PRISMA guidelines. The primary and secondary outcomes were major amputation and death, respectively. Random effects models were developed and the results were presented using surface under the cumulative ranking curve plots and forest plots. A p value of ≤ .050 was considered statistically significant. The Cochrane collaborative tool was used to assess risk of bias. RESULTS: A total of 2 655 participants of whom 94.8% had CLTI were included. Eleven trials compared plain balloon angioplasty (PBA) vs. drug coated balloon (DCB) angioplasty (n = 1 771), five trials compared bare metal stent (BMS) vs. drug coated stent (DCS) (n = 466), three trials compared atherectomy vs. DCB (n = 194), two trials compared PBA vs. BMS (n = 70), one trial compared PBA vs. atherectomy (n = 50), and one trial compared BMS vs. DCB (n = 104). None of the revascularisation strategies significantly reduced the risk of major amputation or death compared with PBA. Using the network estimates, GRADE certainty of evidence for improvement in major amputation outcomes for DCB was moderate, for atherectomy and BMS was low, and for DCS was very low compared with PBA. Risk of bias was low in 16 trials, of some concerns in six trials, and high in one trial, respectively. CONCLUSION: There is no current evidence from RCTs to reliably conclude that BMS, DCB, DCS, or atherectomy are superior to PBA in preventing major amputation and death in patients with CLTI. Larger comparative RCTs are needed to identify the best endovascular revascularisation strategy.

4.
Postgrad Med J ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38679808

RESUMO

BACKGROUND: Low back pain (LBP) is a leading cause of disability worldwide and has posed numerous health and socioeconomic challenges. This study compared whether nonsteroidal anti-inflammatory drugs (NSAIDs) in combination with tramadol, tizanidine or placebo would be the best treatment regime to improve the Roland Morris Disability Questionnaire (RMDQ) scores at 1 week. METHODS: This was a multi-center, double-blind, randomized, and placebo-controlled trial including adult patients with acute LBP and sciatica in three emergency departments in Hong Kong. Patients were randomized to the receive tramadol 50 mg, tizanidine 2 mg, or placebo every 6 hours for 2 weeks in a 1:1:1 ratio. The RMDQ and other secondary outcomes were measured at baseline, Day 2, 7, 14, 21, and 28. Data were analyzed on an intention to treat basis. Crude and adjusted mean differences in the changes of RMDQ and NRS scores from baseline to Day 7 between tizanidine/tramadol and placebo were determined with 95% confidence intervals. RESULTS: Two hundred and ninety-one patients were analyzed with the mean age of 47.4 years and 57.7% were male. The primary outcome of mean difference in RMDQs on Day 7 (compared with baseline) was non-significant for tizanidine compared with placebo (adjusted mean difference - 0.56, 95% CI -2.48 to 1.37) and tramadol compared with placebo (adjusted mean difference - 0.85, 95% CI -2.80 to 1.10). Only 23.7% were fully compliant to the treatment allocated. Complier Average Causal Effect analysis also showed no difference in the primary outcome for the tizanidine and tramadol versus placebo. CONCLUSION: Among patients with acute LBP and sciatica presenting to the ED, adding tramadol or tizanidine to diclofenac did not improve functional recovery.

5.
Br J Neurosurg ; 37(3): 272-276, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32930611

RESUMO

AIM: Cervical anterior spinal fusion (ASF) with corpectomy has risks of catastrophic acute complications such as airway obstruction requiring re-intubation. Our team has adopted a management plan for all cervical corpectomy patients to be admitted to the intensive care unit (ICU) after the operations for overnight observation. Some of these patients were kept intubated after the operations and transferred to the ICU. This study aims to review the outcome of this practice and to identify independent predictors associated with a prolonged ICU stay. METHODS: We reviewed consecutive patients with cervical ASF from January 2010 to June 2018. The primary outcome was the ICU length of stay. Univariate and multivariate analyses were conducted to identify independent risk factors associated with a prolonged ICU stay. In total, 103 patients had ASF during the study period. ICU length of stay for elective ASF was 1.01 day (SD 0.373 days) and was significantly shorter than that for emergency ASF (13.29 days, SD 12.57 days) (p < 0.001). 79.6% (82/103) of the ASF patients were extubated in the operating theatre after surgery. Significantly more corpectomy patients (33.3%) versus ACDF patients (15.1%) were kept intubated to the ICU after the operation (p = 0.037). None required reintubation in the ICU. 90.9% (80/88) of the elective ASF can be discharged from the ICU within 24 hours and only 3.41% (3/88) of the elective ASF had prolonged post-operative stay in the ICU (≥48 hours). RESULTS: For prolonged postoperative ICU stay (≥48 hours), ICU admission airway status of ASF patients who were either extubated in the OT or kept intubated to ICU had no significant association (p = 0.903). Univariate and multivariate analysis had identified emergency admissions (p = 0.043) and the presence of postoperative neurological deficits (p = 0.031) as independent predictors associated with a prolonged postoperative ICU stay. CONCLUSION: In conclusion, cervical corpectomy and ASF were safe with minimal acute complications.


Assuntos
Doenças da Coluna Vertebral , Fusão Vertebral , Humanos , Fusão Vertebral/efeitos adversos , Vértebras Cervicais/cirurgia , Discotomia , Doenças da Coluna Vertebral/cirurgia , Análise Multivariada , Unidades de Terapia Intensiva , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
6.
Food Microbiol ; 104: 103974, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35287803

RESUMO

Thousands of yeasts have the potential for industrial application, though many were initially considered contaminants in the beer industry. However, these organisms are currently considered important components in beers because they contribute new flavors. Non-Saccharomyces wild yeasts can be important tools in the development of new products, and the objective of this work was to obtain and characterize novel yeast isolates for their ability to produce beer. Wild yeasts were isolated from environmental samples from Olympic National Park and analyzed for their ability to ferment malt extract medium and beer wort. Six different strains were isolated, of which Moniliella megachiliensis ONP131 displayed the highest levels of attenuation during fermentations. We found that M. megachiliensis could be propagated in common yeast media, tolerated incubation temperatures of 37 °C and a pH of 2.5, and was able to grow in media containing maltose as the sole carbon source. Yeast cultivation was considerably impacted (p < 0.05) by lactic acid, ethanol, and high concentrations of maltose, but ONP131 was tolerant to high salinity and hop acid concentrations. This is one of the first physiological characterizations of M. megachiliensis, which has potential for the production of beer and other fermented beverages.


Assuntos
Cerveja , Parques Recreativos , Basidiomycota , Cerveja/análise , Fermentação , Saccharomyces cerevisiae
7.
Biochem Biophys Res Commun ; 529(3): 714-719, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32736697

RESUMO

Obesity is associated with metabolic disorders. Fibroblast growth factor 21 (FGF21) has been recognized as important in metabolism. Glucosamine (GLN) has been demonstrated to perform diverse beneficial functions. This study aimed to reveal whether and how GLN would modulate FGF21 production in relation to metabolism. With in vivo model of normal diet (ND) and high-fat diet (HFD) mice receiving GLN injection and in vitro model of mouse AML12 liver cells and differentiated 3T3L1 adipocytes challenged with GLN, GLN appeared to improve the glucose metabolism in HFD and ND mice and to elevate FGF21 protein expression in HFD liver and to increase both FGF21 protein and mRNA levels in WAT from HFD and ND mice and it also upregulated FGF21 expression in both AML12 and differentiated 3T3L1 cells. By using inhibitors against various signaling pathways, p38, Akt, NF-κB, and PKA appeared potentially involved in GLN-mediated FGF21 production in AML12 cells; GLN was able to mediate activation of NF-κB, p38 or PKA/CREB signaling. Our accumulated findings suggest that GLN may potentially improve the metabolic performance by inducing FGF21 production in liver and adipose tissues and such induction in liver cells may act in part due to GLN induction of the NF-κB, p38 and PKA pathways.


Assuntos
Tecido Adiposo/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Glucosamina/metabolismo , Fígado/metabolismo , Células 3T3-L1 , Animais , Fatores de Crescimento de Fibroblastos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regulação para Cima
8.
J Arthroplasty ; 35(11): 3166-3171, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32660798

RESUMO

BACKGROUND: The goal of kinematically aligned (KA) total knee arthroplasty (TKA) is to restore native knee anatomy. However, there are concerns about patellofemoral tracking problems with this technique that lead to early revision. We measured the differences between preoperative anatomic alignment and postoperative component alignment in a consecutive series of KA TKA and evaluated the association between alignment changes and the likelihood of early revision. METHODS: The charts of 219 patients who underwent 275 KA TKA procedures were reviewed. Preoperative anatomic alignment and postoperative tibial and femoral component alignment were measured radiographically. The difference in component alignment compared with preoperative anatomic alignment was compared between patients who underwent aseptic revision and those who did not at a minimum of 12 months of follow-up. Receiver operating characteristic curves were created for statistically significant variables, and the Youden index was used to determine optimal alignment thresholds with regard to likelihood of revision surgery. RESULTS: Change in tibial component alignment compared with native alignment was greater (P = .005) in the revision group (5.0° ± 3.7° of increased varus compared with preoperative anatomic tibial angle) than in the nonrevision group (1.3° ± 4.2° of increased varus). The Youden index indicated that increasing tibial varus by >2.2° or more is associated with increased likelihood of revision. Preoperative anatomic alignment and change in femoral alignment and overall joint alignment (ie, Q angle) were not associated with increased likelihood of revision. CONCLUSION: Small increases in tibial component varus compared with native alignment are associated with early aseptic revision in patients undergoing KA TKA.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Artroplastia do Joelho/efeitos adversos , Fenômenos Biomecânicos , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
9.
Chin J Physiol ; 63(4): 179-186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32859885

RESUMO

PKC-mediated inflammation is important in ovarian physiology. The roles of Akt and protein phosphatase 2A (PP2A) in PKC-mediated inflammation in ovarian granulosa cells (GCs) remain mostly unclear. PKC activator phorbol 12-myristate 13-acetate induced the Akt phosphorylation in rat primary GCs but reduced the Akt phosphorylation in KGN human GCs. In rat GCs, an inhibitory effect of PI3K inhibitor wortmannin and a stimulatory effect of Akt activator SC79 on PKC-induced cyclooxygenase-2 (COX-2)/PGE2production were noted; wortmannin and SC79 acted oppositely in human GCs. In rat GCs, PP2A inhibitor okadaic acid further enhanced the PKC-mediated promoter activation and elevation of mRNA and protein levels of the COX-2 gene, whereas PP2A activator sodium selenate attenuated the PKC-mediated COX-2 expression and promoter activation. PKC activation did not affect PP2A phosphorylation, but okadaic acid indeed augmented the PKC-induced NF-κB nuclear translocation. Thus, PP2A appears to act as a negative modulator in PKC-mediated cellular inflammation in rat GCs, at least in part due to its attenuating effect on the PKC-induced NF-κB activation.


Assuntos
Células da Granulosa , Animais , Feminino , Humanos , Inflamação , Fosfatidilinositol 3-Quinases , Fosforilação , Proteína Fosfatase 2 , Proteínas Proto-Oncogênicas c-akt , Ratos
10.
Biochem Biophys Res Commun ; 503(2): 950-955, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29932914

RESUMO

G protein-coupled receptor (GPCR) activation-mediated PKA and PKC pathways have been recognized to be important in ovarian physiology. Expression of regulator of G-protein signaling 2 (RGS2) has been reported in ovarian granulosa cells. The detailed mechanisms in PKA- and PKC-regulated RGS2 expression and cellular translocation in granulosa cells remain mostly unclear. PKA activator 8-bromo-cAMP and PKC activator phorbol-12, 13-didecanoate appeared to rapidly elevate both protein and mRNA levels and promoter activation of RGS2 gene. Two consensus Sp1 elements within the shortest 78 bp fragment of RGS2 promoter sequence were essential for the full responsiveness to PKA and PKC. PKC activation appeared to increase the RGS2 translocation from nucleus to cytosol. PKA- and PKC-mediated RGS2 transcription in a Sp-1-dependent manner and a PKC-mediated RGS2 intracellular translocation were noted in granulosa cells.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células da Granulosa/metabolismo , Proteína Quinase C/metabolismo , Proteínas RGS/genética , Transdução de Sinais , Ativação Transcricional , Animais , Linhagem Celular , Feminino , Regulação da Expressão Gênica , Camundongos , Regiões Promotoras Genéticas , Transporte Proteico , Proteínas RGS/análise , Proteínas RGS/metabolismo
11.
BMC Biochem ; 18(1): 5, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28320308

RESUMO

BACKGROUND: The smoothelin-like 1 protein (SMTNL1) can associate with tropomyosin (Tpm) and calmodulin (CaM), two proteins essential to the smooth muscle contractile process. SMTNL1 is phosphorylated at Ser301 by protein kinase A during calcium desensitization in smooth muscle, yet the effect of SMTNL1 phosphorylation on Tpm- and CaM-binding has yet to be investigated. RESULTS: Using pull down studies with Tpm-Sepharose and CaM-Sepharose, we examined the interplay between Tpm binding, CaM binding, phosphorylation of SMTNL1 and calcium concentration. Phosphorylation greatly enhanced the ability of SMTNL1 to associate with Tpm in vitro; surface plasmon resonance yielded a 10-fold enhancement in K D value with phosphorylation. The effect on CaM binding is more complex and varies with the availability of calcium. CONCLUSIONS: Combining both CaM and Tpm with SMTNL1 shows that the binding to both is mutually exclusive.


Assuntos
Calmodulina/metabolismo , Proteínas Musculares/metabolismo , Tropomiosina/metabolismo , Animais , Cálcio/metabolismo , Galinhas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Musculares/química , Proteínas Musculares/genética , Músculo Liso/metabolismo , Fosforilação , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
12.
Int J Mol Sci ; 17(8)2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27548147

RESUMO

Cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) are two important inflammatory mediators in ovulation. Ghrelin may modulate inflammatory signaling via growth hormone secretagogue receptors. We investigated the role of ghrelin in KGN human ovarian granulosa cells using protein kinase C (PKC) activator phorbol 12, 13-didecanoate (PDD) and synthetic ghrelin analog growth hormone releasing peptide-2 (GHRP-2). GHRP-2 attenuated PDD-induced expression of protein and mRNA, the promoter activity of COX-2 and IL-8 genes, and the secretion of prostaglandin E2 (PGE2) and IL-8. GHRP-2 promoted the degradation of PDD-induced COX-2 and IL-8 proteins with the involvement of proteasomal and lysosomal pathways. PDD-mediated COX-2 production acts via the p38, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways; PDD-mediated IL-8 production acts via the p38, JNK and ERK pathways. GHRP-2 reduced the PDD-induced phosphorylation of p38 and JNK and activator protein 1 (AP-1) reporter activation and PDD-induced NF-κB nuclear translocation and reporter activation. The inhibitors of mitogen-activated protein kinase phosphatase-1 (MKP-1) and protein phosphatase 2 (PP2A) reduced the inhibitory effect of GHRP-2 on PDD-induced COX-2 and IL-8 expression. Our findings demonstrate an anti-inflammatory role for ghrelin (GHRP-2) in PKC-mediated inflammation of granulosa cells, at least in part, due to its inhibitory effect on PKC-induced activation of p38, JNK and NF-κB, possibly by targeting to MKP-1 and PP2A.


Assuntos
Células da Granulosa/metabolismo , Inflamação/tratamento farmacológico , Oligopeptídeos/farmacologia , Proteína Quinase C/metabolismo , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Grelina/metabolismo , Células da Granulosa/efeitos dos fármacos , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Interleucina-8/metabolismo , Ésteres de Forbol/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição AP-1/metabolismo
13.
J Cell Physiol ; 230(9): 2240-51, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25754990

RESUMO

Breast cancer is a common cancer leading to many deaths among females. Cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) are two highly expressed inflammatory mediators to be induced by the protein kinase C (PKC) signaling via various inflammatory stimuli and both contribute significantly to cancer metastasis/progression. Glucosamine has been shown to act as an anti-inflammation molecule. The aim of this study was to clarify the role and acting mechanism of glucosamine during the PKC-regulation of COX-2/IL-8 expression and the associated impact on breast cancer. In MCF-7 breast cancer cells, glucosamine effectively suppresses the PKC induction of COX-2 and IL-8 promoter activity, mRNA and protein levels, as well as the production of prostaglandin E(2) (PGE(2)) and IL-8. Glucosamine is able to promote COX-2 protein degradation in a calpain-dependent manner and IL-8 protein degradation in calpain-dependent and proteasome-dependent manners. The MAPK and NF-κB pathways are involved in PKC-induced COX-2 expression, but only the NF-κB pathway is involved in PKC-induced IL-8 expression. Glucosamine attenuates PKC-mediated IκBα phosphorylation, nuclear NF-κB translocation, and NF-κB reporter activation. Both PGE(2) and IL-8 promote cell proliferation and IL-8 induces cell migration; thus, glucosamine appears to suppress PKC-induced cell proliferation and migration. Furthermore, glucosamine significantly inhibits the growth of breast cancer xenografts and this is accompanied by a reduction in COX-2 and IL-8 expression. In conclusion, glucosamine seems to attenuate the inflammatory response in vitro and in vivo and this occurs, at least in part by targeting to the NF-κB signaling pathway, resulting in an inhibition of breast cancer cell growth.


Assuntos
Neoplasias da Mama/genética , Ciclo-Oxigenase 2/biossíntese , Interleucina-8/biossíntese , Proteína Quinase C/metabolismo , Animais , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Glucosamina/administração & dosagem , Glucosamina/genética , Humanos , Inflamação/genética , Inflamação/patologia , Células MCF-7 , Camundongos , RNA Mensageiro/biossíntese , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Neurooncol ; 119(1): 27-35, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24792645

RESUMO

Separase, an enzyme that cleaves the chromosomal cohesin during mitosis, is overexpressed in a wide range of human epithelial cancers of breast, bone and prostate (Meyer et al., Clin Cancer Res 15(8):2703-2710, 2009). Overexpression of Separase in animal models results in aneuploidy and tumorigenesis. We have examined the expression and localization of Separase protein in adult and pediatric glioblastoma and normal brain specimens. Immunofluorescence microscopy and Western blot analysis showed significant overexpression of Separase in all adult and a subset of pediatric glioblastoma cells. Tumor status and patient survival strongly correlate with the mislocalization of Separase into the nucleus throughout all stages of the cell cycle. Unlike exclusively nuclear localization in mitotic control cells, glioblastoma samples have a significantly higher number of resting (interphase) cells with strong nuclear Separase staining. Additionally, patient survival analysis demonstrated a strong correlation between overexpression of Separase protein in adult glioblastoma and a high incidence of relapse and reduced overall survival. These results further strengthen our hypothesis that Separase is an oncogene whose overexpression induces tumorigenesis, and indicate that Separase overexpression and aberrant nuclear localization are common in many tumor types and may predict outcome in some human malignancies.


Assuntos
Neoplasias Encefálicas/metabolismo , Núcleo Celular/metabolismo , Glioblastoma/metabolismo , Separase/metabolismo , Regulação para Cima , Neoplasias Encefálicas/mortalidade , Ciclo Celular , Glioblastoma/mortalidade , Humanos , Prognóstico , Recidiva , Taxa de Sobrevida
15.
J Pediatr Orthop ; 34(5): 565-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24915036

RESUMO

BACKGROUND: In the era of methicillin-resistant Staphylococcus aureus, surgical intervention seems to be increasingly common as an adjunct to treatment for pediatric acute hematogenous osteomyelitis (AHO). The purpose of this study is to identify objective clinical and laboratory parameters that are associated with repeated surgical intervention during the acute phase of treatment. METHODS: Fifty-seven children who were consecutively evaluated and treated for AHO at a single institution during 2009 were studied retrospectively. Objective clinical and laboratory parameters related to length of hospitalization were recorded for each child. Univariate analysis was performed with ordinal logistic regression, χ, Fisher exact, and Wilcoxon rank-sum and 2-value tests to identify independent variables associated with the occurrence of surgery in children with AHO. Multivariate logistic regression was used to identify parameters associated with repeated surgical intervention. RESULTS: Sixteen children were treated with antibiotics alone and no surgery. There were 41 children who had at least 1 surgery and 12 who underwent ≥2 surgeries. Multiple logistic regression showed that a swollen extremity (P=0.002), initial C-reactive protein (CRP) value >9.9 mg/dL (P=0.02), and respiration rate >27 breaths/min (P=0.02) were significantly associated with the occurrence of at least 1 surgery. The best model to identify the occurrence of repeated surgical intervention in children with AHO included: ≥4 febrile days on antibiotics; and the CRP values at admission (>19.8 mg/dL), 48 hours after the initial surgery (>21.5 mg/dL), and 96 hours after the initial surgery (>15.3 mg/dL). CONCLUSIONS: Children with AHO who have sustained marked elevation of CRP values during the first 96 hours after surgery and who remain febrile while on antibiotics have an increased likelihood of repeated surgical intervention and should be evaluated carefully for additional surgical treatment. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Assuntos
Proteína C-Reativa/análise , Febre/cirurgia , Osteomielite/cirurgia , Sepse/cirurgia , Doença Aguda , Antibacterianos/uso terapêutico , Criança , Feminino , Febre/sangue , Febre/tratamento farmacológico , Febre/microbiologia , Humanos , Masculino , Osteomielite/sangue , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Reoperação , Estudos Retrospectivos , Sepse/sangue , Sepse/tratamento farmacológico , Sepse/microbiologia
16.
Cureus ; 16(1): e53001, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38406061

RESUMO

BACKGROUND: Patients with recurrent glioblastoma (GBM) have limited treatment options. This study determined whether patients with recurrent GBM treated with initial radiation/temozolomide (TMZ) and reirradiation using fractionated stereotactic radiotherapy (FSRT) had improved outcomes. MATERIALS AND METHODS: We identified 95 patients with recurrent GBM, 50 of whom underwent FSRT at recurrence and 45 who had systemic treatment only (control). The median total FSRT dose at the time of GBM recurrence was 30 Gy in five fractions of the gadolinium-enhanced tumor only. RESULTS: With a median follow-up of 18 months, the progression-free survival (PFS) and overall survival (OS) following initial GBM diagnosis were longer in the reirradiation group compared to the control group (13.5 vs. 7.5 months [p=0.001] and 24.6 vs. 12.6 months [p<0.001], respectively). For patients who underwent reirradiation, the median time interval between the end of the initial radiation and reirradiation was 15.2 months. The median OS after GBM recurrence was longer in the reirradiation group versus the control group (9.9 vs. 3.5 months [p<0.001]), with a one-year OS survival rate of 22%. The hazard ratio for death of patients in the reirradiation group was 0.31 [0.19-0.50]. The reirradiation group had a higher percentage of patients who received bevacizumab (BEV, 62.0% vs. 28.9%, p=0.002) and a lower percentage of patients whose TMZ was discontinued due to toxicity (8.0% vs. 28.9%, p=0.017) compared to the control group. CONCLUSIONS: Reirradiation utilizing FSRT was associated with improved PFS and OS after GBM recurrence compared to the control group who did not receive additional irradiation.

17.
Int J Pharm ; 635: 122694, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36754182

RESUMO

True density is an important physical property of powdered materials, especially in the context of powder compaction. Currently available methods for true density determination either require a significant amount of materials or are laborious. Hence, a material-sparing and efficient method for true density determination is of value. In this work, we detail a simplified buoyancy-based method capable of fast determination of true density with accuracy comparable to helium pycnometry. This miniaturized method only uses a few milligrams of a powder with data collection process expedited by centrifugation in a laboratory centrifuge. This method can be easily adapted in a laboratory since determination of true density only requires a balance, a micropipette, a laboratory centrifuge, and standard stock liquids of low and high densities. Hence, it is a useful addition to the materials characterization tool kit critical for pharmaceutical formulation development.


Assuntos
Fenômenos Físicos , Pós
18.
Invest Ophthalmol Vis Sci ; 64(10): 18, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37459065

RESUMO

Purpose: Transforming growth factor (TGF)-ß2 has been widely implicated in human glaucoma pathology. The purpose of this study was to determine the source of TGF-ß2 in aqueous humor (AH) and its relationship with intraocular pressure (IOP) in an inherited large animal model of glaucoma. Methods: Sixty-six glaucomatous cats homozygous for LTBP2 mutation, and 42 normal cats were studied. IOP was measured weekly by rebound tonometry. AH was collected by anterior chamber paracentesis from each eye under general anesthesia, and serum samples collected from venous blood concurrently. Concentrations of total, active and latent TGF-ß2 in AH and serum samples were measured by quantitative sandwich immunoassay. For comparisons between groups, unpaired t-test or Mann Whitney test were used, with P < 0.05 considered significant. The relationships between TGF-ß2 concentrations and IOP values were examined by Pearson's correlation coefficient and generalized estimating equation. Results: IOP and AH TGF-ß2 concentrations were significantly higher in glaucomatous than in normal cats. AH TGF-ß2 showed a significant, robust positive correlation with IOP in glaucomatous cats (r = 0.83, R2 = 0.70, P < 0.0001). Serum TGF-ß2 did not correlate with AH TGF-ß2 and was not significantly different between groups. TGF-ß2 mRNA and protein expression were significantly increased in local ocular tissues in glaucomatous cats. Conclusions: Enhanced, local ocular production of TGF-ß2 with a robust positive association with IOP was identified in this spontaneous feline glaucoma model, providing a foundation for preclinical testing of novel therapeutics to limit disease-associated AH TGF-ß2 elevation and signaling in glaucoma.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Fator de Crescimento Transformador beta2 , Animais , Gatos , Humanos , Humor Aquoso/metabolismo , Glaucoma/metabolismo , Glaucoma de Ângulo Aberto/metabolismo , Pressão Intraocular , Proteínas de Ligação a TGF-beta Latente/metabolismo , Modelos Animais , Fator de Crescimento Transformador beta2/metabolismo
19.
Can J Cardiol ; 39(7): 936-944, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37080291

RESUMO

BACKGROUND: It is unknown whether the degree of high-sensitivity troponin T (hsTropT) elevation in patients with suspected myocardial infarction without obstructive coronary arteries (MINOCA) presentations can help predict the likelihood of an abnormal cardiac magnetic resonance (CMR) scan. In this study we describe the diagnostic utility of CMR in patients with MINOCA and assesses the effect of peak hsTropT levels at presentation on CMR diagnostic yield. METHODS: Records of consecutive patients (n = 1407) referred for CMR at a tertiary referral hospital between January 2016 and September 2021 were reviewed. A total of 70 patients met the criteria of MINOCA including ischemic chest pain, elevated peak hsTropT, and nonobstructive coronary artery disease (< 50% stenosis). The peak hsTropT levels within 72 hours of admission were identified. CMR images were generated using a 3.0 T Siemens scanner. Predictors of having an abnormal CMR were evaluated. RESULTS: CMR established a diagnosis in 71% (n = 50) of patients, with the most common CMR diagnosis being myopericarditis (n = 27; 39%). Time to CMR was an independent predictor of a normal CMR scan (odds ratio, 0.98; 95% confidence interval, 0.97-0.999). Peak hsTropT had a high diagnostic accuracy for identifying patients with an abnormal CMR scan (area under the receiver operator characteristic curve, 0.81; P < 0.001). The optimal hsTropT cutoff was 166 ng/L, with 72% sensitivity and specificity. A troponin value ≥ 166 ng/L was independently predictive of an abnormal CMR scan (odds ratio, 4.76; 95% confidence interval, 1.32-17.11). CONCLUSIONS: HsTropT and early CMR imaging are independently predictive of an abnormal CMR scan in patients with MINOCA. Additionally, the use of a hsTropT cutoff provides incremental predictive value to clinical parameters and time to CMR scanning in determining an abnormal scan.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Humanos , Troponina T , MINOCA , Angiografia Coronária/métodos , Imageamento por Ressonância Magnética
20.
Neurooncol Adv ; 5(1): vdad031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114245

RESUMO

Background: Laser interstitial thermal therapy (LITT) in the setting of post-SRS radiation necrosis (RN) for patients with brain metastases has growing evidence for efficacy. However, questions remain regarding hospitalization, local control, symptom control, and concurrent use of therapies. Methods: Demographics, intraprocedural data, safety, Karnofsky performance status (KPS), and survival data were prospectively collected and then analyzed on patients who consented between 2016-2020 and who were undergoing LITT for biopsy-proven RN at one of 14 US centers. Data were monitored for accuracy. Statistical analysis included individual variable summaries, multivariable Fine and Gray analysis, and Kaplan-Meier estimated survival. Results: Ninety patients met the inclusion criteria. Four patients underwent 2 ablations on the same day. Median hospitalization time was 32.5 hours. The median time to corticosteroid cessation after LITT was 13.0 days (0.0, 1229.0) and cumulative incidence of lesional progression was 19% at 1 year. Median post-procedure overall survival was 2.55 years [1.66, infinity] and 77.1% at one year as estimated by KaplanMeier. Median KPS remained at 80 through 2-year follow-up. Seizure prevalence was 12% within 1-month post-LITT and 7.9% at 3 months; down from 34.4% within 60-day prior to procedure. Conclusions: LITT for RN was not only again found to be safe with low patient morbidity but was also a highly effective treatment for RN for both local control and symptom management (including seizures). In addition to averting expected neurological death, LITT facilitates ongoing systemic therapy (in particular immunotherapy) by enabling the rapid cessation of steroids, thereby facilitating maximal possible survival for these patients.

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