Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Bone Joint J ; 106-B(4): 380-386, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38555934

RESUMO

Aims: The study aimed to assess the clinical outcomes of arthroscopic debridement and partial excision in patients with traumatic central tears of the triangular fibrocartilage complex (TFCC), and to identify prognostic factors associated with unfavourable clinical outcomes. Methods: A retrospective analysis was conducted on patients arthroscopically diagnosed with Palmer 1 A lesions who underwent arthroscopic debridement and partial excision from March 2009 to February 2021, with a minimum follow-up of 24 months. Patients were assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, Mayo Wrist Score (MWS), and visual analogue scale (VAS) for pain. The poor outcome group was defined as patients whose preoperative and last follow-up clinical score difference was less than the minimal clinically important difference of the DASH score (10.83). Baseline characteristics, arthroscopic findings, and radiological factors (ulnar variance, MRI, or arthrography) were evaluated to predict poor clinical outcomes. Results: A total of 114 patients were enrolled in this study, with a mean follow-up period of 29.8 months (SD 14.4). The mean DASH score improved from 36.5 (SD 21.5) to 16.7 (SD 14.3), the mean MWS from 59.7 (SD 17.9) to 79.3 (SD 14.3), and the mean VAS pain score improved from 5.9 (SD 1.8) to 2.2 (SD 2.0) at the last follow-up (all p < 0.001). Among the 114 patients, 16 (14%) experienced poor clinical outcomes and ten (8.8%) required secondary ulnar shortening osteotomy. Positive ulnar variance was the only factor significantly associated with poor clinical outcomes (p < 0.001). Positive ulnar variance was present in 38 patients (33%); among them, eight patients (21%) required additional operations. Conclusion: Arthroscopic debridement alone appears to be an effective and safe initial treatment for patients with traumatic central TFCC tears. The presence of positive ulnar variance was associated with poor clinical outcomes, but close observation after arthroscopic debridement is more likely to be recommended than ulnar shortening osteotomy as a primary treatment.


Assuntos
Fibrocartilagem Triangular , Traumatismos do Punho , Humanos , Fibrocartilagem Triangular/cirurgia , Prognóstico , Resultado do Tratamento , Estudos Retrospectivos , Artroscopia/efeitos adversos , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia , Traumatismos do Punho/etiologia , Dor/etiologia
2.
Int J Mol Sci ; 24(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958824

RESUMO

We previously reported that glucokinase undergoes ubiquitination and subsequent degradation, a process mediated by cereblon, particularly in the presence of uridine diphosphate glucose (UDP-glucose). In this context, we hereby present evidence showcasing the resilience of variant glucokinase proteins of maturity-onset diabetes of the young type 2 (MODY2) against degradation and, concomitantly, their influence on insulin secretion, both in cell lines and in the afflicted MODY2 patient. Hence, glucose-1-phodphate promotes UDP-glucose production by UDP-glucose pyrophosphorylase 2; consequently, UDP-glucose-dependent glucokinase degradation may occur during fasting. Next, we analyzed glucokinase variant proteins from MODY2 or persistent hyperinsulinemic hypoglycemia in infancy (PHHI). Among the eleven MODY2 glucokinase-mutated proteins tested, those with a lower glucose-binding affinity exhibited resistance to UDP-glucose-dependent degradation. Conversely, the glucokinaseA456V-mutated protein from PHHI had a higher glucose affinity and was sensitive to UDP-glucose-dependent degradation. Furthermore, in vitro studies involving UDP-glucose-dependent glucokinase variant proteins and insulin secretion during fasting in Japanese MODY2 patients revealed a strong correlation and a higher coefficient of determination. This suggests that UDP-glucose-dependent glucokinase degradation plays a significant role in the pathogenesis of glucose-homeostasis-related hereditary diseases, such as MODY2 and PHHI.


Assuntos
Diabetes Mellitus Tipo 2 , Uridina Difosfato Glucose , Humanos , Diabetes Mellitus Tipo 2/genética , Jejum , Glucoquinase/genética , Glucoquinase/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Mutação
4.
J Hand Surg Eur Vol ; 48(9): 872-876, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37226467

RESUMO

Trapeziometacarpal arthrodesis is used for the treatment of advanced arthritis. Insufficient stabilization of the joint may lead to nonunion or hardware problems after arthrodesis. The purpose of this study was to compare the biomechanical properties of dorsal versus radial plate fixation of the trapeziometacarpal joint in ten pairs of fresh-frozen cadaveric hands. The biomechanical performance of each group was measured for stiffness in extension and flexion and load to failure using cantilever bending tests. The stiffness in extension was lower in the dorsally positioned group than in the radially positioned group (12.1 versus 15.2 N/mm, respectively). Load to failure was comparable between both groups (53.9 versus 50.9 N, respectively). A radially positioned locking plate for trapeziometacarpal arthrodesis may be biomechanically advantageous.

5.
Sci Rep ; 12(1): 14568, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36028536

RESUMO

Insulin secretion is regulated in multiple steps, and one of the main steps is in the endoplasmic reticulum (ER). Here, we show that UDP-glucose induces proinsulin ubiquitination by cereblon, and uridine binds and competes for proinsulin degradation and behaves as sustainable insulin secretagogue. Using insulin mutagenesis of neonatal diabetes variant-C43G and maturity-onset diabetes of the young 10 (MODY10) variant-R46Q, UDP-glucose:glycoprotein glucosyltransferase 1 (UGGT1) protects cereblon-dependent proinsulin ubiquitination in the ER. Cereblon is a ligand-inducible E3 ubiquitin ligase, and we found that UDP-glucose is the first identified endogenous proinsulin protein degrader. Uridine-containing compounds, such as uridine, UMP, UTP, and UDP-galactose, inhibit cereblon-dependent proinsulin degradation and stimulate insulin secretion from 3 to 24 h after administration in ß-cell lines as well as mice. This late and long-term insulin secretion stimulation is designated a day sustainable insulin secretion stimulation. Uridine-containing compounds are designated as proinsulin degradation regulators.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animais , Glucose , Insulina , Camundongos , Proinsulina , Uridina , Uridina Difosfato Glucose
6.
Int J Mol Sci ; 23(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36012359

RESUMO

We previously reported that glucokinase is ubiquitinated and degraded by cereblon with an unknown endogenous glucokinase protein degrader. Here, we show that UDP-glucose is a glucokinase protein degrader. We identified that both glucose and UDP-glucose bind to glucokinase and that both uridine and UDP-glucose bind to cereblon in a similar way to thalidomide. From these results, UDP-glucose was identified as a molecular glue between cereblon and glucokinase. Glucokinase produces glucose-6-phosphate in the pancreas and liver. Especially in ß-cells, glucokinase is the main target of glucose for glucose-induced insulin secretion. UDP-glucose administration ubiquitinated and degraded glucokinase, lowered glucose-6-phosphate production, and then reduced insulin secretion in ß-cell lines and mice. Maturity-onset diabetes of the young type 2 (MODY2) glucokinaseE256K mutant protein was resistant to UDP-glucose induced ubiquitination and degradation. Taken together, glucokinase ubiquitination and degradation signaling might be impaired in MODY2 patients.


Assuntos
Diabetes Mellitus Tipo 2 , Glucoquinase , Animais , Diabetes Mellitus Tipo 2/metabolismo , Glucoquinase/genética , Glucoquinase/metabolismo , Glucose/metabolismo , Glucose-6-Fosfato , Insulina/metabolismo , Camundongos , Mutação , Uridina Difosfato Glucose
7.
Micromachines (Basel) ; 13(7)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35888887

RESUMO

In this paper, we propose and analyze a novel interposer channel structure with vertical tabbed vias to achieve high-speed signaling and low-power consumption in high-bandwidth memory (HBM). An analytical model of the self- and mutual capacitance of the proposed interposer channel is suggested and verified based on a 3D electromagnetic (EM) simulation. We thoroughly analyzed the electrical characteristics of the novel interposer channel considering various design parameters, such as the height and pitch of the vertical tabbed via and the gap of the vertical channel. Based on the frequency-dependent lumped circuit resistance, inductance, and capacitance, we analyzed the channel characteristics of the proposed interposer channel. In terms of impedance, insertion loss, and far-end crosstalk, we analyzed how much the proposed interposer channel improved the signal integrity characteristics compared to a conventional structure consisting of micro-strip and strip lines together. Compared to the conventional worst case, which is the strip line, the eye-width, the eye-height, and eye-jitter of the proposed interposer channel were improved by 17.6%, 29%, and 9.56%, respectively, at 8 Gbps. The proposed interposer channel can reduce dynamic power consumption by about 28% compared with the conventional interposer channel by minimizing the self-capacitance of the off-chip channel.

8.
Biochem Biophys Res Commun ; 615: 131-135, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35613513

RESUMO

Arginine releases proinsulin from binding to UGGT1 in the endoplasmic reticulum (ER). PSIPRED analysis showed that the arginine/proinsulin binding domain (A/PBD) in the C-terminal region of UGGT1 forms a disordered region, which is flexible and outside of the main protein structure. Both arginine and proinsulin may easily access the disordered region of A/PBD. Using the SNP library, two variants, Q1518∗ and R1526C, were identified in this region. UGGT1Q1518∗ protein is a deficient form of A/PBD and ER-retention signal (ERRS). UGGT1Q1518∗ protein in cell analysis reveals that mutated protein is mainly secreted from the cells because it lacks ERRS. We found another UGGT1 variant, UGGT1R1526C. At the molecular level, less interaction of proinsulin with UGGT1 was observed in both human UGGT1R1526C and mouse UGGT1L1518C with/without arginine. However, UGGT1R1526C and UGGT1WT interact with arginine similarly. We identified several amino acid residues for the arginine and proinsulin interaction. Here, the R1526 residue of UGGT1 is involved in proinsulin-interaction and is not involved in arginine-interaction.


Assuntos
Proinsulina , Dobramento de Proteína , Animais , Arginina/metabolismo , Fenômenos Biofísicos , Retículo Endoplasmático/metabolismo , Glucosiltransferases/metabolismo , Insulina/metabolismo , Camundongos , Proinsulina/genética
9.
Surg Today ; 52(7): 1109-1114, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35018512

RESUMO

PURPOSE: At present, ≥ 20% of patients experience clinically relevant postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP). METHODS: We developed a new bioabsorbable pancreatic clip (BioPaC) made of polycaprolactone that does not crush the pancreatic parenchyma during occlusion of the pancreatic stump. We confirmed the efficacy of this BioPac in a porcine DP model and compared it to a linear stapling device (Reinforce®). RESULTS: Pigs were killed at 1 month after DP. In the BioPaC group, all swine (n = 3) survived well without POPF. In the Reinforce® group (n = 2), one pig died early at postoperative day 7 with Grade C POPF (amylase 43 700 U/l), and the other survived until 1 month at scarification with biochemical leakage of POPF (amylase 3 725 U/l). Pathologically, the main pancreatic duct and pancreatic parenchyma were well closed by BioPaC. CONCLUSION: The newly developed BioPaC is effective in a porcine DP model.


Assuntos
Implantes Absorvíveis , Pancreatectomia , Amilases , Animais , Humanos , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Instrumentos Cirúrgicos , Suínos
10.
Biochem Biophys Res Commun ; 579: 110-115, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34597993

RESUMO

The liver increases its size during pregnancy to adapt to metabolic demand associated with pregnancy. Our previous study showed that proliferation of maternal hepatocytes are increased during pregnancy in mice and that estradiol (E2) is one of the candidate hormones responsible for maternal hepatocyte proliferation. Here, we discovered that chorionic gonadotropin (CG) induces maternal hepatocyte proliferation during pregnancy. CG administration was sufficient to stimulate hepatocyte proliferation in non-pregnant mice as well as in cell culture system. We conclude that CG stimulates proliferation in the early pregnancy of maternal hepatocytes. In contrast, estrogen stimulates hepatocyte proliferation in the late pregnancy.


Assuntos
Gonadotropina Coriônica/metabolismo , Estradiol/metabolismo , Hepatócitos/citologia , Prenhez , Envelhecimento , Animais , Proliferação de Células , Células Cultivadas , Estrogênios/metabolismo , Feminino , Células HEK293 , Células Hep G2 , Humanos , Hormônio Luteinizante/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Placenta/metabolismo , Gravidez , Ligação Proteica , Fatores de Tempo
11.
Front Plant Sci ; 12: 756795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650585

RESUMO

Phytochromes are red and far-red photoreceptors that regulate plant growth and development under ambient light conditions. During phytochrome-mediated photomorphogenesis, phytochrome-interacting factors (PIFs) are the most important signaling partners that regulate the expression of light-responsive genes. However, the function of PIFs in monocots has not been studied well. In this study, using RNA interference (RNAi), we investigated the functions of BdPIL1 and BdPIL3, two PIF-like genes identified in Brachypodium distachyon, which are closely related to Arabidopsis PIF1 and PIF3. The expression of their genes is light-inducible, and both BdPIL1 and BdPIL3 proteins interact with phytochromes in an active form-specific manner. Transgenic Brachypodium seedlings with the RNAi constructs of BdPIL1 and BdPIL3 showed decreased coleoptile lengths and increased leaf growth when exposed to both red and far-red light. In addition, the transgenic plants were taller with elongated internodes than wild-type Bd21-3 plant, exhibiting late flowering. Moreover, RNA-seq analysis revealed downregulation of many genes in the transgenic plants, especially those related to the regulation of cell number, floral induction, and chlorophyll biosynthesis, which were consistent with the phenotypes of increased plant height, delayed flowering, and pale green leaves. Furthermore, we demonstrated the DNA-binding ability of BdPIL1 and BdPIL3 to the putative target promoters and that the DNA-binding was inhibited in the presence of phytochromes. Therefore, this study determines a molecular mechanism underlying phytochrome-mediated PIF regulation in Brachypodium, i.e., sequestration, and also elucidates the functions of BdPIL1 and BdPIL3 in the growth and development of the monocot plant.

12.
Front Plant Sci ; 12: 706316, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394163

RESUMO

Plant phytochromes are known as autophosphorylating serine/threonine protein kinases. However, the functional importance of their kinase activity is not fully elucidated. Previously, the kinase activity is shown to be necessary for the function of Avena sativa phytochrome A (AsphyA) using transgenic plants with mutants displaying reduced kinase activity, such as K411L and T418D. In this study, we isolated and analyzed two AsphyA mutants, K411R and T418V, that showed increased kinase activity. Transgenic phyA-201 plants with these mutants showed hypersensitive responses to far-red (FR) light, such as shorter hypocotyls and more expanded cotyledons than those of control plant (i.e., transgenic phyA-201 plant with wild-type AsphyA). Contrary to the mutants with reduced kinase activity, these mutants accelerated FR-induced phosphorylation and subsequent degradation of phytochrome-interacting factor 3 (PIF3) in Arabidopsis. Moreover, elongated hypocotyl 5 (HY5), a critical positive regulator of photoresponses in plants, accumulated in higher amounts in the transgenic plants under FR light than in the control plant. In addition, PIF1 degradation was accelerated in the transgenic plants. Consequently, the transgenic plants exhibit higher germination frequencies than the control plant. Collectively, our results demonstrate that the AsphyA mutants with increased kinase activity are hyperactive in plants, supporting a positive relationship between the kinase activity of phytochromes and photoresponses in plants.

13.
Plant Cell Physiol ; 62(9): 1446-1459, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34155514

RESUMO

Trichomes are hair-like structures that are essential for abiotic and biotic stress responses. Tomato Hair (H), encoding a C2H2 zinc finger protein, was found to regulate the multicellular trichomes on stems. Here, we characterized Solyc10g078990 (hereafter Hair2, H2), its closest homolog, to examine whether it was involved in trichome development. The H2 gene was highly expressed in the leaves, and its protein contained a single C2H2 domain and was localized to the nucleus. The number and length of type I trichomes on the leaves and stems of knock-out h2 plants were reduced when compared to the wild-type, while overexpression increased their number and length. An auto-activation test with various truncated forms of H2 using yeast two-hybrid (Y2H) suggested that H2 acts as a transcriptional regulator or co-activator and that its N-terminal region is important for auto-activation. Y2H and pull-down analyses showed that H2 interacts with Woolly (Wo), which regulates the development of type I trichomes in tomato. Luciferase complementation imaging assays confirmed that they had direct interactions, implying that H2 and Wo function together to regulate the development of trichomes. These results suggest that H2 has a role in the initiation and elongation of type I trichomes in tomato.


Assuntos
Dedos de Zinco CYS2-HIS2/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Caules de Planta/crescimento & desenvolvimento , Solanum lycopersicum/genética , Tricomas/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Tricomas/genética
14.
Arthroscopy ; 37(2): 450-456, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33007408

RESUMO

PURPOSE: To determine how intraoperative assessment (engagement test) may affect recurrent dislocation rate and to compare the clinical outcomes, recurrence rates, and presence of on-/off-track conditions between cases that received arthroscopic Bankart repair alone (nonengaged Hill-Sachs lesion) and Bankart repair with remplissage (engaged Hill-Sachs lesion). METHODS: We retrospectively reviewed 213 patients who underwent arthroscopic Bankart repair alone (186 patients with nonengaging lesions, group A) or with remplissage (27 patients with engaging lesion, group B) for recurrent anterior shoulder instability with <25% glenoid bone defect. The presence of an engaging Hill-Sachs lesion was determined during arthroscopic evaluation. On-track or off-track lesions were assessed retrospectively from preoperative 3-dimensional (3D) computed tomography (CT). RESULTS: Mean glenoid bone defect was 13.7% in group A and 20.7% in group B (P < .001). Off-track lesions were identified in 8.1% (15/186) and 100% (27/27) in group B. At the final follow-up (minimum 2 years; mean follow-up periods after surgery of 50.1 months in group A and 47.7 months in group B), there were no significant differences in shoulder functional scores and recurrence rates between groups, despite improvement after surgery. In the off-track lesion (group A-1: nonengaging but off-track lesion), recurrence instability occurred in 9 patients (60%, 9/15). Also, comparing group A-1 and group B, we noted significant differences in shoulder functional scores and recurrence rates (P < .001). CONCLUSION: Of 186 patients, 8.1% with nonengaging Hill-Sachs lesions during direct arthroscopic examination under anesthesia actually demonstrated off-track lesions on preoperative 3D CT scans retrospectively, with 60% experiencing recurrent instability. Intraoperative manual assessment for Hill-Sachs engagement was inferior to 3D CT scan in establishing the presence of off-track defects. LEVEL OF EVIDENCE: III, retrospective comparative study.


Assuntos
Lesões de Bankart/cirurgia , Adulto , Artroscopia , Lesões de Bankart/diagnóstico por imagem , Lesões de Bankart/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Estudos Retrospectivos , Articulação do Ombro/fisiopatologia , Articulação do Ombro/cirurgia , Esportes , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
15.
Commun Biol ; 3(1): 497, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901087

RESUMO

We sought to determine a mechanism by which L-arginine increases glucose-stimulated insulin secretion (GSIS) in ß-cells by finding a protein with affinity to L-arginine using arginine-immobilized magnetic nanobeads technology. Glucokinase (GCK), the key regulator of GSIS and a disease-causing gene of maturity-onset diabetes of the young type 2 (MODY2), was found to bind L-arginine. L-Arginine stimulated production of glucose-6-phosphate (G6P) and induced insulin secretion. We analyzed glucokinase mutants and identified three glutamate residues that mediate binding to L-arginine. One MODY2 patient with GCKE442* demonstrated lower C-peptide-to-glucose ratio after arginine administration. In ß-cell line, GCKE442* reduced L-arginine-induced insulin secretion compared with GCKWT. In addition, we elucidated that the binding of arginine protects glucokinase from degradation by E3 ubiquitin ligase cereblon mediated ubiquitination. We conclude that L-arginine induces insulin secretion by increasing G6P production by glucokinase through direct stimulation and by prevention of degradation.


Assuntos
Arginina/farmacologia , Glucoquinase/metabolismo , Glucose-6-Fosfato/biossíntese , Células Secretoras de Insulina/metabolismo , Ubiquitinação , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular , Diabetes Mellitus Tipo 2/patologia , Glucose-6-Fosfato/metabolismo , Ácido Glutâmico/metabolismo , Células HEK293 , Humanos , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ubiquitina-Proteína Ligases , Ubiquitinação/efeitos dos fármacos
16.
Biochem Biophys Res Commun ; 527(3): 668-675, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32423812

RESUMO

We sought to clarify a pathway by which L- and dD-arginine simulate insulin secretion in mice and cell lines and obtained the following novel two findings. (1) Using affinity magnetic nanobeads technology, we identified that proinsulin is retained in the endoplasmic reticulum (ER) through UDP-glucose:glycoprotein glucosyltransferase 1 (UGGT1) when arginine availability is limited. (2) L- and d-arginine release proinsulin from UGGT1 through competition with proinsulin and promote exit of proinsulin from the ER to Golgi apparatus. The ability of arginine to release proinsulin from UGGT1 closely correlates with arginine-induced insulin secretion in several models of ß cells indicating that UGGT1-proinsulin interaction regulates arginine-induced insulin secretion.


Assuntos
Arginina/metabolismo , Retículo Endoplasmático/metabolismo , Glucosiltransferases/metabolismo , Proinsulina/metabolismo , Animais , Células Cultivadas , Células HEK293 , Humanos , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Modelos Moleculares
17.
Clin Biomech (Bristol, Avon) ; 76: 105021, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32416405

RESUMO

BACKGROUND: Comparative studies of the biomechanical effects of plates of varying lengths and different screw insertion angles on allograft spacers are lacking. METHODS: Finite element model analysis of a previously validated, three-dimensional, intact cervical spinal segment model of C3-6 was conducted in the present study. On the C5-6 segment, anterior discectomy and fusion were performed using allograft spacers and different combinations of anterior plates and screws. The biomechanical characteristics of combinations of short, medium, and maximal length plates with screw insertion angles of 0°, 8°, 16°, and 32° were analyzed. FINDINGS: In flexion and extension, the risk of allograft spacer subsidence decreased as screw angles increased. Short plates with a screw insertion angle of 32° posed the lowest subsidence risk, similar to medium length plates with a screw insertion angle of 16°, in all motion conditions. The risk of bone yielding increased as plate length increased, but decreased as the screw insertion angle increased. INTERPRETATION: Short plates with a large screw insertion angle (32°) showed the highest mechanical stability and load sharing of allograft spacers and the lowest risk of screw loosening. Accordingly, we recommend the use of a short plate and large screw insertion angle for anterior cervical discectomy and fusion.


Assuntos
Placas Ósseas , Parafusos Ósseos , Vértebras Cervicais/cirurgia , Análise de Elementos Finitos , Aloenxertos/cirurgia , Fenômenos Biomecânicos , Humanos , Transplante Homólogo
18.
EMBO Rep ; 20(10): e47828, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31393060

RESUMO

Growth plasticity is a key mechanism by which plants adapt to the ever-changing environmental conditions. Since growth is a high-energy-demanding and irreversible process, it is expected to be regulated by the integration of endogenous energy status as well as environmental conditions. Here, we show that trehalose-6-phosphate (T6P) functions as a sugar signaling molecule that coordinates thermoresponsive hypocotyl growth with endogenous sugar availability. We found that the loss of T6P SYNTHASE 1 (TPS1) in Arabidopsis thaliana impaired high-temperature-mediated hypocotyl growth. Consistently, the activity of PIF4, a transcription factor that positively regulates hypocotyl growth, was compromised in the tps1 mutant. We further show that, in the tps1 mutant, a sugar signaling kinase KIN10 directly phosphorylates and destabilizes PIF4. T6P inhibits KIN10 activity in a GRIK-dependent manner, allowing PIF4 to promote hypocotyl growth at high temperatures. Together, our results demonstrate that T6P determines thermoresponsive growth through the KIN10-PIF4 signaling module. Such regulation of PIF4 by T6P integrates the temperature-signaling pathway with the endogenous sugar status, thus optimizing plant growth response to environmental stresses.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Transdução de Sinais , Fosfatos Açúcares/metabolismo , Temperatura , Trealose/análogos & derivados , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucose/farmacologia , Modelos Biológicos , Morfogênese/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sacarose/farmacologia , Trealose/metabolismo
19.
Methods Mol Biol ; 2026: 95-111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31317405

RESUMO

Expression and purification of recombinant proteins are important for the structure-function study of phytochromes. However, it is difficult to purify phytochrome proteins from natural sources or using a bacterial expression system, due to the presence of multiple phytochrome species and low expression and solubility, respectively. Here we describe the expression of recombinant full-length plant phytochromes in the yeast Pichia pastoris, and the spectral analysis of chromophore-assembled phytochromes before and after the purification by streptavidin affinity chromatography.


Assuntos
Fitocromo/química , Fitocromo/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Cromatografia de Afinidade , Fitocromo/isolamento & purificação , Pichia/metabolismo , Proteínas Recombinantes/isolamento & purificação , Saccharomyces cerevisiae/metabolismo
20.
Oncologist ; 21(9): 1085-90, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27401892

RESUMO

BACKGROUND: The phase II YO28252 study (NCT01590719) examined first-line onartuzumab plus mFOLFOX6 in patients with metastatic, human epidermal growth factor receptor 2-negative adenocarcinoma of the stomach or gastroesophageal junction. MET immunohistochemistry expression as a biomarker of onartuzumab activity was also examined. PATIENTS AND METHODS: Patients were randomized 1:1 to receive standard mFOLFOX6 plus onartuzumab (10 mg/kg) or placebo in 2-week cycles for 12 cycles, followed by onartuzumab or placebo until disease progression. Coprimary endpoints were progression-free survival (PFS) in intent-to-treat (ITT) and MET-positive populations. The target hazard ratio (HR) was 0.70 for patients in the ITT group and 0.60 in the MET-positive population. Secondary endpoints were overall survival (OS), overall response rate (ORR), and safety. RESULTS: Overall, 123 patients were enrolled (n = 62 onartuzumab, n = 61 placebo). Median PFS was 6.77 versus 6.97 months for onartuzumab versus placebo, respectively (HR, 1.08; 95% confidence interval [CI], 0.71-1.63; p = .71). In the MET-positive population, median PFS was 5.95 versus 6.80 months, onartuzumab versus placebo (HR, 1.38; 95% CI, 0.60-3.20; p = .45). Median OS was 10.61 months for onartuzumab versus 11.27 months for placebo) (HR, 1.06, 0.64-1.75; p = .83). In the MET-positive population, median OS was 8.51 versus 8.48 months for onartuzumab versus placebo, respectively (HR, 1.12, 95% CI, 0.45-2.78; p = .80). ORR was 60.5% for the onartuzumab group and 57.1% for placebo. Grade 3-5 adverse events (AEs) were seen in 88.3% of patients receiving onartuzumab and in 78.3% of patients receiving placebo, with serious AEs in 55% and 40%, respectively. CONCLUSION: The addition of onartuzumab to mFOLFOX6 in gastric cancer did not improve efficacy in an unselected population or in a MET immunohistochemistry-positive population. IMPLICATIONS FOR PRACTICE: The YO28252 study demonstrated that the addition of the anti-MET agent onartuzumab to mFOLFOX6 for treatment of gastric cancer did not improve efficacy in an overall study population or those selected for positive MET status by immunohistochemistry. This highlights the importance of correctly selecting biomarkers for targeted therapies. A multivariate analysis suggested that MET positivity may still be prognostic for worse median overall survival in gastric cancer; therefore, it is important to continue investigation into the optimal approach to inhibit MET signaling in gastric cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Esofágicas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/efeitos dos fármacos , Junção Esofagogástrica/patologia , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Compostos Organoplatínicos/administração & dosagem , Proteínas Proto-Oncogênicas c-met/genética , Neoplasias Gástricas/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...