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1.
Clin Rheumatol ; 43(5): 1763-1775, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38446355

RESUMEN

OBJECTIVE: To report a statistical evaluation of symptomatology based on 56 cases of SAPHO syndrome and 352 non-SAPHO involvement cases, to propose a symptomatic scoring system in consideration of early warning for SAPHO syndrome. METHODS: A cohort comprising 56 subjects diagnosed with SAPHO syndrome was reported, as well as 352 non-SAPHO involvement cases, including their chief complaints, skin manifestations, radiological findings, and laboratory tests. We systematically reviewed previous published five representative huge cohorts from different countries to conclude several specific features of SAPHO by comparing with our case series. The score of each specific index is based on respective incidence and comparison of two cohorts was performed. RESULT: In terms of complaint rates, all subjects of two cohorts suffered from osseous pain, which appeared in the anterior chest wall, spine, and limb which were calculated. In respect to dermatological lesions, SAPHO patients suffered from severe acne, and other patients (82.14%) accompanied with palmoplantar pustulosis. Having received radiological examinations, most SAPHO subjects rather than non-SAPHO involvement cases showed abnormal osteoarticular lesions under CT scanning and more detailed information under whole-body bone scintigraphy. Differences also emerged in elevation of inflammation values and rheumatic markers like HLA-B27. Based on our cases and huge cohorts documented, the early warning standard is set to be 5 scores. CONCLUSIONS: SAPHO syndrome case series with 56 subjects were reported and an accumulative scoring system for the early reminder on SAPHO syndrome was proposed. The threshold of this system is set to be 5 points. Key Points • Fifty-six patients diagnosed by SAPHO syndrome with detailed symptoms and radiological findings were reported. • Comparison was made between the 56 SAPHO patients and 352 non-SAPHO involvement cases. • An accumulative scoring system for the early reminder on SAPHO syndrome was proposed and the threshold of this system is set to be five points.


Asunto(s)
Síndrome de Hiperostosis Adquirido , Humanos , Síndrome de Hiperostosis Adquirido/diagnóstico por imagen , Cintigrafía , Huesos/patología , Radiografía , Columna Vertebral/patología
2.
Exp Ther Med ; 27(4): 159, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38476885

RESUMEN

Erdheim-Chester disease (ECD) is a rare tumor of histiocytic origin, characterized by foamy or lipid-laden histiocytes mixed or surrounded by fibrosis that infiltrate multiple organs. Misdiagnosis is common due to the diversity of clinical presentations. The present study reported a case of ECD with the involvements of bone, cardiac, aorta and retroperitoneum. The patient had no obvious clinical symptoms and no noteworthy foamy histiocytes or Touton giant cells were found on pathological examination, delaying the diagnosis. The patient was a young male found to have pericardial effusion on physical examination, and computed tomography (CT) revealed soft tissue infiltrates in the retroperitoneum and around the aorta. A mediastinal biopsy revealed fibrous connective tissue with small-vessel hyperplasia and acute-chronic inflammatory cell infiltration. The initial diagnosis was retroperitoneal fibrosis (RPF), and hormonal and tamoxifen treatments were administered. The patient presented with oliguria, eyelid edema and fever four years later. A repeat CT revealed an increase in the extent of tissue infiltration and pericardial effusion compared with the previous CT. Subsequent cardiac magnetic resonance imaging revealed massive thickening in the form of fibrotic tissue infiltrating the heart and surrounding thoracic and abdominal aorta. Single photon emission CT revealed multiple areas of increased bone metabolism, particularly symmetrical involvement of the long bones of both lower extremities. A biopsy of the perirenal tissue revealed fibrous tissue and a small number of lymphocytes and macrophages [typical foamy histiocytes observed via x200 magnification and hematoxylin-eosin (HE) staining, no presence of xanthogranuloma or Touton giant cells]. After a comprehensive evaluation and ruling out other diseases, the diagnosis of ECD was determined. The prognosis of this disease is poor; early diagnosis is critical and requires accurate judgment by clinicians. Biopsies of all involved sites and refinement of genetic tests to guide treatment, if possible, are both necessary.

3.
Exp Ther Med ; 27(4): 162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38476911

RESUMEN

The present study aimed to compare the differences between minimally invasive transforaminal lumbar fusion (MIS-TLIF) and open transforaminal lumbar fusion (TLIF) for multi-segmental lumbar degenerative disease regarding intraoperative indices and postoperative outcomes. PubMed, Web of Science, Embase, CNKI, Wanfang and VIP databases were searched for literature on MIS-TLIF and open TLIF in treating multi-segmental lumbar degenerative diseases. Of the 1,608 articles retrieved, 10 were included for final analysis. The Newcastle-Ottawa Scale and Review Manager 5.4 were used for quality evaluation and data analysis, respectively. The MIS-TLIF group was superior to the open TLIF group regarding intraoperative blood loss [95% confidence interval (CI): -254.33,-157.86; P<0.00001], postoperative in-bed time (95%CI: -3.49,-2.76; P<0.00001), hospitalization time (95%CI: -5.14,-1.78; P<0.0001) and postoperative leg pain Visual Analog Scale score (95%CI: -0.27,-0.13; P<0.00001). The fluoroscopy frequency for MIS-TLIF (95%CI: 2.07,6.12; P<0.0001) was significantly higher than that for open TLIF. The two groups had no significant differences in operation time, postoperative drainage volume, postoperative complications, fusion rate, or Oswestry Disability Index score. In treating multi-segmental lumbar degenerative diseases, MIS-TLIF has the advantages of less blood loss, shorter bedtime and hospitalization time and improved early postoperative efficacy; however, open TLIF has a lower fluoroscopy frequency.

4.
Front Immunol ; 14: 1237209, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38098481

RESUMEN

Background: Clinically amyopathic dermatomyositis (CADM) is a distinct subtype of dermatomyositis (DM) characterized by typical DM cutaneous findings but with minimal or no evidence of myositis. It possesses unique features different from classic DM (CDM). Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies were found in CADM and are thought to increase the risk of rapidly progressive interstitial lung disease (RP-ILD) and are present in both CADM and CDM patients, affecting their condition and prognosis. Nevertheless, no large-sample studies have compared all aspects concerning patients with CADM and those with CDM. This study aimed to investigate differences in clinical characteristics and risk factors for mortality between CADM and CDM and to clarify the distribution and impact of anti-MDA5 antibodies in patients with these conditions. Methods: A retrospective case-control study included 330 patients and collected and analyzed their clinical data from The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Hospital of Traditional Chinese Medicine between January 2015 and July 2022; all patients were followed up to evaluate changes in their condition and prognosis. Several new cohorts were designed around anti-MDA5 antibodies to explore their distribution and impact in CADM and CDM. Results: We found CADM to be associated with higher rates of mortality, 1-year mortality, interstitial lung disease (ILD), and RP-ILD than CDM. In CADM, RP-ILD, anti-MDA5 antibodies, and high ferritin and lactate dehydrogenase (LDH) levels were identified as independent risk factors for death. In CDM, the neutrophil-to-lymphocyte ratio, anti-MDA5 antibodies, and high ferritin levels were shown to be independent risk factors for death, whereas mechanic's hand was considered a protective factor against it. Anti-MDA5 antibody-positive patients did not exhibit any significant difference based on whether they belonged to the CADM or CDM groups. When no anti-MDA5 antibody-positive patients participated, the ferritin levels and rates of RP-ILD and ILD were still higher in CADM than in CDM; however, such differences decreased, whereas the LDH levels, rates of mortality, and 1-year mortality did not differ. Anti-MDA5 antibody-positive patients consistently showed higher LDH and ferritin levels, lower lymphocyte levels, higher probability of RP-ILD and ILD, and worse prognosis than anti-MDA5 antibody-negative patients, irrespective of whether the patients had DM, CADM, or CDM. Conclusion: Patients with CADM exhibit relatively worse symptoms, serological findings, and prognosis than those with CDM. Furthermore, patients with CADM and those with CDM have commonalities and differences in risk factors for death. Moreover, CADM may necessitate earlier and more aggressive treatment strategies than CDM. Anti-MDA5 antibodies occur at a high level in patients with CADM, not only affecting the symptoms and prognosis of DM but also having a non-negligible impact on the differences between CADM and CDM. Hence, screening for anti-MDA5 antibodies in patients with CADM and CDM is extremely essential.


Asunto(s)
Dermatomiositis , Enfermedades Pulmonares Intersticiales , Humanos , Estudios de Casos y Controles , Dermatomiositis/diagnóstico , Ferritinas , Helicasa Inducida por Interferón IFIH1 , Enfermedades Pulmonares Intersticiales/diagnóstico , Estudios Retrospectivos
5.
Micromachines (Basel) ; 14(4)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37421124

RESUMEN

Abrasive water jetting is an effective dressing method for a fixed abrasive pad (FAP) and can improve FAP machining efficiency and the impact of abrasive water jet (AWJ) pressure on the dressing effect; moreover, the machining state of FAP after dressing has not been thoroughly studied. Therefore, in this study, the FAP was dressed by using AWJ under four pressures, and the dressed FAP was subjected to lapping experiments and tribological experiments. Through an analysis of the material removal rate, FAP surface topography, friction coefficient, and friction characteristic signal, the influence of AWJ pressure on the friction characteristic signal in FAP processing was studied. The outcomes show that the impact of the dressing on FAP rises and then falls as the AWJ pressure increases. The best dressing effect was observed when the AWJ pressure was 4 MPa. In addition, the maximum value of the marginal spectrum initially rises and then falls as the AWJ pressure increases. When the AWJ pressure was 4 MPa, the peak value of the marginal spectrum of the FAP that was dressed during processing was the largest.

6.
Medicine (Baltimore) ; 101(33): e30065, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35984163

RESUMEN

RATIONALE: SAPHO syndrome is a rare clinical entity characterized by a wide range of dermatological and musculoskeletal manifestations. Treatment strategies are not standardized. Palmoplantar pustulosis (PPP) is the most common rash in patients with SAPHO syndrome. PATIENT CONCERNS: A 24-year-old Chinese woman with no relevant medical or familial history had a 1-year history of cutaneous lesions with PPP and pain in the sternoclavicular joint. DIAGNOSIS: Based on the diagnostic criteria for SAPHO syndrome proposed by Nguyen et al in 2012, we diagnosed SAPHO syndrome with severe PPP as the predominant manifestation. INTERVENTIONS: Due to the limited therapeutic efficacy of methotrexate and cyclosporin, we started therapy with subcutaneous secukinumab 150 mg weekly for the first month, then 150 mg monthly thereafter. OUTCOMES: After 4 weeks of secukinumab administration, the patient showed significant remission of pustular skin lesions, with almost no joint pain and no adverse reaction. Complete remission of skin symptoms was achieved after 3 months. Joint pain and adverse events have not reoccurred in follow-up thus far. CONCLUSIONS: In patients with SAPHO syndrome, we recommend personalized treatment, which may have excellent therapeutic efficacy in those with PPP or severe skin symptoms. Although data related to the use of IL-17 blockers for SAPHO syndrome are very limited, secukinumab provides a novel therapeutic option, especially for patients with PPP and severe skin lesions. Further prospective studies are needed to support our findings.


Asunto(s)
Síndrome de Hiperostosis Adquirido , Psoriasis , Síndrome de Hiperostosis Adquirido/complicaciones , Síndrome de Hiperostosis Adquirido/diagnóstico , Síndrome de Hiperostosis Adquirido/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales Humanizados/uso terapéutico , Femenino , Humanos , Dolor , Adulto Joven
7.
Materials (Basel) ; 15(15)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35955184

RESUMEN

Clarifying the influence of the dress process parameters of the abrasive water jet on the dressing effect of fixed-abrasive pads (FAPs) is a prerequisite for online controllable dressing of abrasive water jets. This paper uses three factors and three horizontal response surface methods to explore the influence of jet pressure, abrasive concentration, and nozzle angle on FAP dressing quality. The prediction model of the material removal rate of a FAP machined using three process parameters is established. The influence of pairwise interactions of the three process parameter variables on the dressing effect and the optimal process parameters under each target is analyzed. Finally, the optimal process parameters predicted by the model are verified by experiments. The results show that the best dressing parameters with the MRR of the workpiece as the response value are as follows: jet pressure 3.8 MPa, abrasive concentration 3%, and nozzle angle 73°. The predicted value of the optimal process performance is 464.574 nm/min, and the experimental verification result is 469.136 nm/min; the error between the experimental value and the predicted value is within a reasonable range.

8.
Micromachines (Basel) ; 13(7)2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35888798

RESUMEN

The surface condition of the fixed abrasive pad (FAP) has a significant impact on its machining performance, workpiece material removal rate (MRR), and surface roughness. To clarify the wavelet packet energy characteristics of friction signal under different surface conditions of FAP and its mapping relationship with MRR and workpiece surface quality, FAP samples in different processing stages were obtained through a consolidated abrasive grinding quartz glass experiment. Then, the friction signals in different stages were received by the friction and wear experiment between the FAP and quartz glass workpiece, and the wavelet packet analysis was carried out. The experimental results show that with the increase of lapping time, the surface wear degree of the FAP increased gradually, and the MRR of the workpiece, the surface roughness of the FAP, and the surface roughness of the workpiece decreased slowly. In the wavelet packet energy of friction signal during machining, the energy proportion of frequency band 7 showed an upward trend with the increase of lapping time. The energy proportion of frequency band 8 showed a downward trend with the increase of lapping time. The change characteristics of the two are significantly correlated with the surface condition of the FAP.

10.
J Int Med Res ; 49(12): 3000605211065314, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34932408

RESUMEN

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is an umbrella term covering a constellation of bone lesions and skin manifestations, but has rarely been clarified in the clinic. We report a 28-year-old woman who had initial onset of SAPHO syndrome with involvement of the femur, and she experienced a tortuous diagnostic course. We also performed a literature review of SAPHO syndrome cases involving the femur and summarize several empirical conclusions by integrating previous findings with our case. Furthermore, we propose our perspective that ailment of the skin caused by infection of pathogens might be the first hit for triggering or perpetuating the activation of the immune system. As a result, musculoskeletal manifestations are probably the second hit by crosstalk of an autoimmune reaction. The skin manifestations preceding bone lesions can be well explained. Current interventions for SAPHO syndrome remain controversial, but drugs aiming at symptom relief could serve as the first preference for treatment. An accurate diagnosis and appropriate treatment can cure patients in a timely manner. Although the pathogenesis of SAPHO syndrome remains to be determined, physicians and surgeons still need to heighten awareness of this entity to avoid invasive procedures, such as frequent biopsies or nonessential ostectomy.


Asunto(s)
Acné Vulgar , Síndrome de Hiperostosis Adquirido , Neoplasias Femorales , Hiperostosis , Osteítis , Sinovitis , Síndrome de Hiperostosis Adquirido/diagnóstico , Síndrome de Hiperostosis Adquirido/tratamiento farmacológico , Adulto , Femenino , Humanos , Osteítis/diagnóstico por imagen , Osteítis/tratamiento farmacológico
11.
Micromachines (Basel) ; 12(12)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34945397

RESUMEN

Na2CO3-1.5 H2O2, KClO3, KMnO4, KIO3, and NaOH were selected for dry polishing tests with a 6H-SiC single crystal substrate on a polyurethane polishing pad. The research results showed that all the solid-phase oxidants, except NaOH, could decompose to produce oxygen under the frictional action. After polishing with the five solid-phase oxidants, oxygen was found on the surface of SiC, indicating that all five solid-phase oxidants can have complex tribochemical reactions with SiC. Their reaction products are mainly SiO2 and (SiO2)x. Under the action of friction, due to the high flash point temperature of the polishing interface, the oxygen generated by the decomposition of the solid-phase oxidant could oxidize the surface of SiC and generate a SiO2 oxide layer on the surface of SiC. On the other hand, SiC reacted with H2O and generated a SiO2 oxide layer on the surface of SiC. After polishing with NaOH, the SiO2 oxide layer and soluble Na2SiO3 could be generated on the SiC surface; therefore, the surface material removal rate (MRR) was the highest, and the surface roughness was the largest, after polishing. The lowest MRR was achieved after the dry polishing of SiC with KClO3.

12.
Medicine (Baltimore) ; 100(9): e24620, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33655926

RESUMEN

RATIONALE: Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant disorder characterized by congenital skeletal deformities and soft tissue masses that progress into heterotopic ossification. Deformities of the great toes are distinctive and heterotrophic ossification usually begins in the first decade of the patient's life. Any invasive procedure could potentially trigger a flare and heterotopic calcification. The diagnosis is difficult and there is no effective treatment for FOP and the approximate life expectancy is 4 decades. PATIENT CONCERNS: A 22-year-old male patient who had suffered from pain and movement limitations for 14 years. At the early stage of disease, the child underwent an operation on both thighs with a diagnosis of myophagism. He had serious stiffness and multiple bony masses with the characteristic bilateral hallux valgus deformity and microdactyly. DIAGNOSES: The patient was diagnosed with FOP by the help of characteristic great toe malformations and widespread heterotopic ossification throughout the body. Deoxyribonucleic acid sequencing demonstrated that the patient had a de novo heterozygous mutation (c.617G>A; p.R206H) in activin A receptor/activin-like kinase 2. INTERVENTIONS: We administered a co-therapy of glucocorticoids, NSAIDs to relieve pain, and montelukast for 2 months. Bisphosphonate (5 mg, intravenous) was used once. OUTCOMES: At the follow-up 12 months later, the patient still felt low back pain sometimes and need take NSAIDs three times a week. LESSONS: Clinicians and radiologists should realize the characteristic features of FOP and early diagnosis can prevent additional invasive harm to the patient.


Asunto(s)
Receptores de Activinas Tipo I/genética , Mutación/genética , Miositis Osificante/genética , Hallux/anomalías , Heterocigoto , Humanos , Masculino , Osificación Heterotópica/genética , Adulto Joven
13.
Free Radic Biol Med ; 165: 219-228, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33539948

RESUMEN

Lipopolysaccharide (LPS) has been known to cause alveolar epithelial cell (AEC) apoptosis and barrier breakdown that characterize acute lung injury (ALI) and acute respiratory distress syndrome. We aimed to investigate whether mitoquinone (MitoQ), a mitochondria-targeted antioxidant, could alleviate LPS-induced AEC damage in ALI and its underlying mechanisms. In vitro studies in AEC A549 cell line, we noted that LPS could induce dynamin-related protein 1 (Drp1)-mediated mitochondrial fission, AEC apoptosis and barrier breakdown, which could be reversed with MitoQ and mitochondrial division inhibitor 1 treatment. Moreover, the protective role of MitoQ was attenuated with Drp1 overexpression. Nuclear factor E2-related factor 2 (Nrf2) downregulation could block the effect of MitoQ by decreasing the expression of Nrf2 target genes in LPS-treated AEC, such as heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1). Nrf2 gene knockdown in LPS-treated A549 cells prevented the protective effect of MitoQ from decreasing Drp1-mediated mitochondrial fission, AEC apoptosis and barrier breakdown. The lung protective effect of MitoQ by regulating the Drp1-mediated mitochondrial fission, AEC apoptosis and barrier breakdown was further confirmed in vivo with LPS-induced ALI mouse model. Additionally, the protective effect of MitoQ was inhibited by Nrf2 inhibitor ML385. We therefore conclude that MitoQ exerts ALI-protective effects by preventing Nrf2/Drp1-mediated mitochondrial fission, AEC apoptosis as well as barrier breakdown.


Asunto(s)
Lesión Pulmonar Aguda , Factor 2 Relacionado con NF-E2 , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/genética , Animales , Dinaminas , Lipopolisacáridos/toxicidad , Ratones , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Compuestos Organofosforados , Transducción de Señal , Ubiquinona/análogos & derivados
14.
Artículo en Inglés | MEDLINE | ID: mdl-32952587

RESUMEN

Osteoarthritis (OA) is an increasingly prevalent disease affecting synovial joints, which includes joint degeneration, inflammation, and joint pain. The activation of nucleotide-binding and oligomerization domain-like receptor containing protein 3 (NLRP3) could promote synovial inflammation. Previous studies have shown that electroacupuncture (EA) has potential anti-inflammatory effect. However, the effect of EA treatment on OA remains unclear. The aim of this study was to investigate the effect of applied EA on OA and joint pain and its relationship with NLRP3 inflammasome. The Hartley guinea pigs with naturally occurring OA at age 18 months were chosen as the OA model and treated with EA for 4 weeks. Mechanical allodynia was quantified by using von Frey filaments. The expression of NLRP3 inflammasome and the downstream proinflammatory factors in the cartilage tissue were quantified. Our results showed that EA treatment significantly reduces mechanical allodynia, improves the articular cartilage structure, and decreases the fibrillation on the cartilage surface in guinea pigs with spontaneous osteoarthritis. Moreover, we also found that EA treatment attenuates the NLRP3 inflammasome activation and suppresses the protein expression levels of caspase-1 and IL-1ß in the cartilage tissue. Our findings suggest that EA treatment attenuates OA and joint pain by suppressing NLRP3 inflammasome activation and support further investigation of the potential therapeutic tactics.

15.
J Pain Res ; 13: 1747-1756, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765049

RESUMEN

PURPOSE: The causative mechanisms triggering myofascial pain syndrome (MPS) are still in debate. It is becoming evident that mitochondrial dysfunction may regulate pathways controlling MPS. The aim of this study was to investigate whether AMPK-PGC-1α-SIRT3 axis is associated with depression of mitochondrial function in the rat MPS model. METHODS: A total of 32 Sprague-Dawley rats were randomly divided into control group and experimental group. The expression level of mRNA and protein of gastrocnemius medialis (GM) was analyzed by Western blot and RT-PCR. The histopathological findings were investigated through electron microscopes in GM of all groups. RESULTS: Our results showed that MPS induces continuous depression of mitochondrial biogenesis and function via down-regulation of PGC-1α-SIRT3 axis accompanying with ATP fuel crisis as compared to control group. However, the expression level of SIRT3 mRNA did not change. Additionally, a correlated reduction of the mRNA and protein expression level of NRF-1 and TFAM, known as the downstream target of PGC-1α, suggesting further transcription of nuclear genes encoding mitochondria functional proteins for promoting mitochondria proliferation, oxidative phosphorylation and energy production is continuously depressed. Furthermore, phosphorylation extent of AMPK is also declined following MPS, and it is negatively correlated with reduction of ATP generation, suggesting that the complex network involves different inhibition in transcription, post-translational modification and a plethora of other effectors that mediate the inhibition roles. CONCLUSION: We here suggested that the down-regulation in AMPK-PGC-1α-SIRT3 axis network may be the basis for the association between mitochondrial dysfunction and MPS, where a vicious circle further aggravates the disease symptoms with ongoing ATP energy crisis.

16.
Micromachines (Basel) ; 11(5)2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32414034

RESUMEN

Micro-end-milling is a cutting technology that removes redundant material from machined workpieces by small-diameter end mills, and is widely used to manufacture miniature complex parts. During micro-end-milling, the cutting vibration caused by weak tool rigidity and high spindle speed is known as a key factor for decreasing machined quality and accelerating tool failure. This study reports on experiments of micro-end-milling of the straight groove for AISI 1045 steel. The waveform characteristics of acceleration vibration were revealed, the relationship between acceleration and milling parameters were analyzed and two types of relationship models were developed. The results show that, during micro-end-milling of the straight groove, the components of acceleration vibration from largest to smallest are in turn the transverse acceleration αY, the feed acceleration αX and the axial acceleration αZ. Compared with feed velocity vf and axial depth of cut ap, the spindle speed n has the highest influence on cutting vibration. The response surface model of acceleration vibration was shown to have a higher prediction accuracy compared to the power function model and is more suitable for the prediction and control of cutting vibration during micro-end-milling.

17.
Inflammation ; 42(3): 895-903, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30680695

RESUMEN

Cardiopulmonary bypass (CPB) can induce inflammatory lung injury, which is a common complication during cardiac surgery. Nod-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome-induced inflammation plays a crucial role in lung injury after CPB. Previous studies have shown that electroacupuncture (EA) has potential anti-inflammatory activity. However, the role of EA in CPB is poorly understood. The aim of this study was to determine whether EA was associated with CPB-induced inflammatory lung injury. In the present study, rats were treated with EA for 5 days before CPB. Two hours after CPB, the lung tissue, serum, and bronchoalveolar lavage fluid (BALF) were prepared for assessment. Our results showed that the expression of NLRP3 in the lung tissue increased significantly after CPB. The EA pretreatment suppressed NLRP3 inflammasome activation, reduced lung edema, and inhibited IL-1ß release into the serum and BALF after CPB. Our findings suggest that EA pretreatment attenuates inflammatory lung injury after CPB by suppressing NLRP3 inflammasome activation.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Puente Cardiopulmonar/efectos adversos , Electroacupuntura/métodos , Inflamasomas/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Neumonía/prevención & control , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/patología , Animales , Líquido del Lavado Bronquioalveolar/química , Edema/prevención & control , Inflamasomas/metabolismo , Interleucina-1beta/antagonistas & inhibidores , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Neumonía/etiología , Ratas
18.
Plant Sci ; 277: 285-295, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30466594

RESUMEN

Proteinaceous α-amylase inhibitors have specialized activities that make some strong inhibition of α-amylases. New α-amylase inhibitors continue to be discovered so far. A proteinaceous α-amylase inhibitor CL-AI was isolated and identified from chickpea seeds. CL-AI, encoded by Q9SMJ4, was a storage legumin precursor containing one α-chain and one ß-chain, and each chain possessed a same conserved cupin domain. Amino acid mutation and deficiency of cupin domain would lead to loss of α-amylase inhibitory activity, indicating that it was essential for inhibitory activity. CL-AI(α + ß) in its single stranded state in vivo had inhibitory activity. After it was processed into one α-chain and one ß-chain, the two chains were connected to each other via disulfide bond, which would cover the cupin domains and lead to the loss of inhibitory activity. The CL-AI(α + ß), α-chain and ß-chain could inhibit various α-amylases and delay the seed germination of wheat, rice and maize as well as the growth and development of potato beetle larva. Two cupin proteins, Glycinin G1 in soybean and Glutelinin in rice were also found to have inhibitory activity. Our results indicated that the cupin domain is involved in α-amylase inhibitory activity and the proteins with a cupin domain may be a new kind of proteinaceous α-amylase inhibitor.


Asunto(s)
Activación Enzimática/genética , Inhibidores Enzimáticos/farmacología , Plantas/enzimología , Dominios Proteicos/fisiología , alfa-Amilasas/metabolismo , Cicer/enzimología , Activación Enzimática/efectos de los fármacos , Globulinas/metabolismo , Oryza/enzimología , Proteínas de Plantas/metabolismo , Solanum tuberosum/enzimología , Triticum/enzimología , Zea mays/enzimología , alfa-Amilasas/antagonistas & inhibidores
19.
Materials (Basel) ; 11(8)2018 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-30115890

RESUMEN

A series of silicon-doped lithium manganese oxides were obtained via a sol-gel process. XRD characterization results indicate that the silicon-doped samples retain the spinel structure of LiMn2O4. Electrochemical tests show that introducing silicon ions into the spinel structure can have a great effect on reversible capacity and cycling stability. When cycled at 0.5 C, the optimal Si-doped LiMn2O4 can exhibit a pretty high initial capacity of 140.8 mAh g-1 with excellent retention of 91.1% after 100 cycles, which is higher than that of the LiMn2O4, LiMn1.975Si0.025O4, and LiMn1.925Si0.075O4 samples. Moreover, the optimal Si-doped LiMn2O4 can exhibit 88.3 mAh g-1 with satisfactory cycling performance at 10 C. These satisfactory results are mainly contributed by the more regular and increased MnO6 octahedra and even size distribution in the silicon-doped samples obtained by sol-gel technology.

20.
Materials (Basel) ; 11(8)2018 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-30060499

RESUMEN

The LiCuxMn1.95-xSi0.05O4 (x = 0, 0.02, 0.05, 0.08) samples have been obtained by a simple solid-state method. XRD and SEM characterization results indicate that the Cu-Si co-doped spinels retain the inherent structure of LiMn2O4 and possess uniform particle size distribution. Electrochemical tests show that the optimal Cu-doping amount produces an obvious improvement effect on the cycling stability of LiMn1.95Si0.05O4. When cycled at 0.5 C, the optimal LiCu0.05Mn1.90Si0.05O4 sample exhibits an initial capacity of 127.3 mAh g-1 with excellent retention of 95.7% after 200 cycles. Moreover, when the cycling rate climbs to 10 C, the LiCu0.05Mn1.90Si0.05O4 sample exhibits 82.3 mAh g-1 with satisfactory cycling performance. In particular, when cycled at 55 °C, this co-doped sample can show an outstanding retention of 94.0% after 100 cycles, whiles the LiMn1.95Si0.05O4 only exhibits low retention of 79.1%. Such impressive performance shows that the addition of copper ions in the Si-doped spinel effectively remedy the shortcomings of the single Si-doping strategy and the Cu-Si co-doped spinel can show excellent cycling stability.

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