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1.
Water Res ; 199: 117161, 2021 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-33971533

RESUMEN

The disposal and resource utilization of waste activated sludge (WAS) is a big challenge for its high moisture content. Ionic liquid (IL), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][OTf]), was innovatively used as a conditioner to improve the dewatering performance of WAS. The WAS was characterized by flocs size, three-dimensional excitation-emission matrix (3D-EEM), zeta potential, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) for the investigation of intensification mechanism. The results showed that the dewatering performance of WAS conditioned by [EMIM][OTf] was significantly improved. The moisture content was successfully decreased to 64.99±0.92 %, and the intensification mechanism was investigated. The results showed that the structures of extracellular polymeric substance (EPS) were destroyed by [EMIM][OTf]. It brought a sharp decrease of the contents of polysaccharides (PS), proteins (PN), humic acid (HA) and fulvic acid (FA) in tightly bound extracellular polymeric substance (TB-EPS) structure. The inactivation of microbial cells promoted the disintegration of flocs. Large flocs were converted into unstable small particles and biopolymers. In addition, the negative charges of WAS were also neutralized for dissolution of biopolymers in [EMIM][OTf], and the electrostatic repulsion between flocs was weakened. [EMIM][OTf] was easily recycled five times. The research results indicate that specific IL, such as [EMIM][OTf], is a potential conditioner to improve the dewatering performance of WAS.

2.
Ecotoxicol Environ Saf ; 218: 112308, 2021 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-33975224

RESUMEN

Accumulating studies have revealed the toxicity of antimony (Sb) to soil-dwelling and aquatic organisms at the individual level. However, little is known about the neurotoxic effects of antimony and its underlying mechanisms. To assess this issue, we investigated the neurotoxicity of antimony (0, 200, 400, 600 and 800 mg/L) in zebrafish embryos. After exposure, zebrafish embryos showed abnormal phenotypes such as a shortened body length, morphological malformations, and weakened heart function. Behavioral experiments indicated that antimony caused neurotoxicity in zebrafish embryos, manifested in a decreased spontaneous movement frequency, delayed response to touch, and reduced movement distance. We also showed that antimony caused a decrease in acetylcholinesterase (AChE) levels in zebrafish embryos, along with decreased expression of neurofunctional markers such as gfap, nestin, mbp, and shha. Additionally, antimony significantly increased reactive oxygen species levels and significantly reduced glutathione (GSH) and superoxide dismutase (SOD) activity. In summary, our findings indicated that antimony can induce developmental toxicity and neurotoxicity in zebrafish embryos by affecting neurotransmitter systems and oxidative stress, thus altering behavior. These outcomes will advance our understanding of antimony-induced neurotoxicity, environmental problems, and health hazards.

3.
Orthop Surg ; 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-33977666

RESUMEN

OBJECTIVE: This study aimed to investigate the value of a horizontal rafting plate in treating tibial plateau fractures. METHODS: The data of 24 patients in whom a horizontal rafting plate was used to treat a tibial plateau fracture between October 2014 and January 2018 were retrospectively analyzed, including 16 males and 8 females, aged 21-63 years old, with an average of 40 ± 14.68 years. The fractures included 13 in the left knee and 11 in the right knee. The places where the horizontal rafting plate were used included the anterior margin of tibia, anterolateral tibia, and posterolateral tibia. All cases were followed up for 12-24 months, with an average follow-up of 17.5 ± 5.0 months. At the last follow-up, the Rasmussen radiological criteria were used to evaluate the effect of fracture reduction and fixation. The knee joint function was evaluated using the Rasmussen functional score. Computed tomography (CT) scanning and three-dimensional reconstruction were performed preoperatively and postoperatively, with the quality of reduction of the fractured articular surface clarified by the final follow-up. The flexion and extension abilities of the knee joint were also measured in the postoperative follow-up. RESULTS: Preoperative CT scanning showed that the gap of the tibial plateau was 8.00 ± 1.40 (5-24) mm. The heights of the fracture of the articular surface at all three sites during the final follow-ups were significantly different from the height before the surgery (P < 0.05). The vertical distance between the articular line and the highest point of the articular surface after reduction was 0.17 ± 0.05 mm. Anatomic reductions were obtained in 24 patients. The Rasmussen functional score after surgeries was 27.25 ± 0.94 points. Bony union was achieved in all the patients. According to the Rasmussen radiological criteria, the scores during the last follow-up were as follows: the total score was 13-18 points, with an average of 16.00 ± 1.72 points; the scores were excellent in 17 cases and good in seven cases. Therefore, 100% of results were excellent or good. No infection or fracture nonunion was found. CONCLUSION: Using a horizontal plate can be an effective method for treating special types of fractures of the tibial plateau, including the anterior margin and anterolateral and posterolateral tibial plateau, with satisfactory treatment efficacy.

4.
Food Funct ; 12(9): 4046-4059, 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-33977945

RESUMEN

Previous studies have reported that Portulaca oleracea L. polysaccharides (POL-P3b) is an immunoregulatory agent. However, few studies exist on POL-P3b as a novel immune adjuvant in combination with the DC vaccine for breast cancer treatment. In this work, a DC vaccine loaded with mouse 4T1 tumor cell antigen was prepared to evaluate the properties of POL-P3b in inducing the maturation and function of DC derived from mouse bone marrow, and then to investigate the effect of the DC vaccine combined with POL-P3b on breast cancer in vivo and in vitro. Morphological changes of DC were observed using scanning electron microscopy. Phenotypic and functional analyses of DC were detected by flow cytometry and allogeneic lymphocyte reaction. Cytokine levels in the DC culture supernatant were detected by ELISA. Western blotting analysis was used for the protein expression of TLR4, MyD88 and NF-κB. Apoptosis detection and protein expression of the tumor tissue were analyzed by TUNEL staining and immunohistochemistry, respectively. The security of POL-P3b was evaluated by the detection of hematological and blood biochemical indicators and pathological analysis for tissues. POL-P3b can induce DC activation and maturation, which is attributed to increasing the specific anti-tumor immune response, and the mechanism of action involved in the TLR4/MyD88/NF-κB signaling pathway. Experimental results in vivo further suggested that the administration of POL-P3b-treated antigen-primed DC achieved remarkable tumor growth inhibition through inducing apoptosis and enhancing immune responses. Moreover, the POL-P3b-treated DC vaccine was able to inhibit lung metastases. The results proved the feasibility of POL-P3b as an edible adjuvant of the DC vaccine for anti-breast cancer therapy.

5.
Aging (Albany NY) ; 132021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33946048

RESUMEN

Fibroblasts are a highly heterogeneous population in tumor microenvironment. PDGFR-ß+ fibroblasts, a subpopulation of activated fibroblasts, have proven to correlate with cancer progression through multiple of mechanisms including inducing angiogenesis and immune evasion. However, the prognostic role of these cells in solid tumors is still not conclusive. Herein, we carried out a meta-analysis including 24 published studies with 6752 patients searched from PubMed, Embase and EBSCO to better comprehend the value of such subpopulation in prognosis prediction for solid tumors. We noted that elevated density of intratumoral PDGFR-ß+ fibroblasts was remarkably associated with worse overall survival (OS) and disease-free survival (DFS) of patients. In subgroup analyses, the data showed that PDGFR-ß+ fibroblast infiltration considerably decreased OS in non-small cell lung cancer (NSCLC), breast and pancreatic cancer, and reduced DFS in breast cancer. In addition, increased number of PDGFR-ß+ fibroblasts appreciably correlated with advanced TNM stage of patients. In conclusion, PDGFR-ß+ fibroblast infiltration deteriorates survival in human solid tumors especially in NSCLC, breast and pancreatic cancer. Hence, they may offer a practicable prognostic biomarker and a potential therapeutic strategy for these patients.

6.
Mater Sci Eng C Mater Biol Appl ; 124: 112054, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33947548

RESUMEN

Breast cancer is the most common cancer among women worldwide, of which 10-20% accounts for triple-negative breast cancer (TNBC). TNBC is more aggressive, lacks an effective treatment target, and has a higher metastasis rate compared to other types of breast cancers. These characteristics result in poor therapeutic and prognostic outcomes in patients with TNBC. Sonodynamic therapy (SDT) is an emerging non-invasive procedure with high-tissue penetration properties to treat cancer. Therefore, we designed a new sonosensitizer, PEG-IR780@Ce6 for SDT, which showed excellent performance in inhibiting cancer cells and in simultaneously suppressing the migration and invasion of cancer cells. In vitro and in vivo experiments showed that PEG-IR780@Ce6 as a sonosensitizer could generate higher levels of reactive oxygen species (ROS) than IR780 and free Ce6 alone, thereby resulting in better anti-cancer effects. Besides, PEG-IR780@Ce6 inhibited the migration and invasion of MDA-MB-231 cells, both in vitro and in vivo, which indicated that it could suppress the metastasis of TNBC. Moreover, the long circulation time and the mitochondria-targeting ability of PEG-IR780@Ce6 guaranteed its accumulation in the tumor. In addition, both in vitro and in vivo experiments indicated the biocompatibility and biosafety of PEG-IR780@Ce6. In conclusion, our results collectively suggested that the newly designed sonosensitizer, PEG-IR780@Ce6, is a promising treatment option for TNBC with excellent therapeutic effects and low side effects.

7.
Thorac Cancer ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33949784

RESUMEN

BACKGROUND: To investigate the survival benefit of concurrent chemoradiotherapy (CCRT) for patients with locally advanced esophageal squamous cell carcinoma (ESCC) during the years of intensity-modulated radiotherapy (IMRT). METHODS: Medical records of 1089 patients with ESCC who received IMRT from January 2005 to December 2017 were retrospectively reviewed. A total of 617 patients received CCRT, 472 patients received radiotherapy (RT) alone. Propensity score matching (PSM) method was used to eliminate baseline differences between the two groups. Survival and toxicity profile were evaluated afterward. RESULTS: After a median follow-up time of 47.9 months (3.2-149.8 months), both overall survival (OS) and progression-free survival (PFS) of the CCRT group were better than those of the RT alone group, either before or after PSM. After PSM, the 1-, 3-, and 5-year OS of RT alone and CCRT groups were 59.0% versus 70.2%, 27.7% versus 40.5% and 20.3% versus 33.1%, respectively (p < 0.001). The 1-, 3-, and 5-year PFS were 39.4% versus 49.0%, 18.3% versus 30.4% and 10.5% versus 25.0%, respectively (p < 0.001). The rates of ≥ grade 3 leukopenia and radiation esophagitis in the CCRT group were higher than that of RT alone group (p < 0.05). There was no significant difference in the probability of radiation pneumonitis between the two groups (p = 0.167). Multivariate Cox analysis indicated that female, EQD2 ≥60 Gy and concurrent chemotherapy were favorable prognostic factors for both OS and PFS. CONCLUSIONS: Concurrent chemotherapy can bring survival benefits to patients with locally advanced ESCC receiving IMRT. For patients who cannot tolerate concurrent chemotherapy, RT alone is an effective alternative with promising results.

8.
Sci Adv ; 7(19)2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33952527

RESUMEN

The checkpoint kinase ATR [ATM (ataxia-telangiectasia mutated) and rad3-related] is a master regulator of DNA damage response. Yet, how ATR activity is regulated remains to be investigated. We report here that histone demethylase PHF8 (plant homeodomain finger protein 8) plays a key role in ATR activation and replication stress response. Mechanistically, PHF8 interacts with and demethylates TOPBP1 (DNA topoisomerase 2-binding protein 1), an essential allosteric activator of ATR, under unperturbed conditions, but replication stress results in PHF8 phosphorylation and dissociation from TOPBP1. Consequently, hypomethylated TOPBP1 facilitates RAD9 (RADiation sensitive 9) binding and chromatin loading of the TOPBP1-RAD9 complex to fully activate ATR and thus safeguard the genome and protect cells against replication stress. Our study uncovers a demethylation and phosphorylation code that controls the assembly of TOPBP1-scaffolded protein complex, and provides molecular insight into non-histone methylation switch in ATR activation.

9.
Aging (Albany NY) ; 132021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33952718

RESUMEN

Glycolysis ensures energy supply to cancer cells, thereby facilitating tumor progression. Here, we identified glycolysis-related genes that could predict the prognosis of patients with osteosarcoma. We examined 198 glycolysis-related genes that showed differential expression in metastatic and non-metastatic osteosarcoma samples in the TARGET database, and identified three genes (P4HA1, ABCB6, and STC2) for the establishment of a risk signature. Based on the signature, patients in the high-risk group had poor outcomes. An independent Gene Expression Omnibus database GSE21257 was selected as the validation cohort. Receiver operating characteristic curve analysis was performed and the accuracy of predicting the 1- and 3-year survival rates was shown by the areas under the curve. The results were 0.884 and 0.790 in the TARGET database, and 0.740 and 0.759 in the GSE21257, respectively. Furthermore, we applied ESTIMATE algorithm and performed single sample gene set enrichment analysis to compare tumor immunity between high- and low-risk groups. We found that the low-risk group had higher immune scores and immune infiltration levels than the high-risk group. Finally, we chose P4HA1 as a representative gene to verify the function of risk genes in vitro and in vivo and found that P4HA1 could promote the metastasis of osteosarcoma cells. Our study established a novel glycolysis-related risk signature that could predict the prognosis of patients with osteosarcoma.

10.
Plant Cell ; 33(3): 566-580, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33955496

RESUMEN

The external application of nitrogen (N) fertilizers is an important practice for increasing crop production. However, the excessive use of fertilizers significantly increases production costs and causes environmental problems, making the improvement of crop N-use efficiency (NUE) crucial for sustainable agriculture in the future. Here we show that the rice (Oryza sativa) NUE quantitative trait locus DULL NITROGEN RESPONSE1 (qDNR1), which is involved in auxin homeostasis, reflects the differences in nitrate (NO3-) uptake, N assimilation, and yield enhancement between indica and japonica rice varieties. Rice plants carrying the DNR1indica allele exhibit reduced N-responsive transcription and protein abundance of DNR1. This, in turn, promotes auxin biosynthesis, thereby inducing AUXIN RESPONSE FACTOR-mediated activation of NO3- transporter and N-metabolism genes, resulting in improved NUE and grain yield. We also show that a loss-of-function mutation at the DNR1 locus is associated with increased N uptake and assimilation, resulting in improved rice yield under moderate levels of N fertilizer input. Therefore, modulating the DNR1-mediated auxin response represents a promising strategy for achieving environmentally sustainable improvements in rice yield.

11.
Diagn Cytopathol ; 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33969933

RESUMEN

BACKGROUND: Cytopathologists reviewing pulmonary specimens are expected to classify samples into clinically useful categories. Clinicians prefer reports to convey a definitively benign or definitively malignant diagnosis. Cytopathologists recognize a spectrum of morphologic features with increasing degrees of atypia between clearly benign and clearly malignant. A variety of terms are used to convey to clinicians how concerned a cytologist is that a malignancy maybe present. These terms include "atypia", "atypical" and "suspicious for malignancy", but have had variable meanings among cytopathologists and clinicians. Categorization schemes have been proffered to include standardization of terminology with many of these systems containing one or more intermediate categories. METHODS: An electronic search of the University of Missouri cytology reporting system was made for all bronchial brushings specimens diagnosed using the Papanicolaou Society of Cytopathology System for Reporting Respiratory Cytology (PSCSR) between January 2019 and December 2019. Slides were reviewed to determine adequate cellularity and preparation quality. From those found to be adequately cellular and of good quality, four bronchial brushing specimens from each PSCSR category were randomly selected. For each case a slide was digitized and at least 70 of the most "atypical" cells were analyzed by the Aperio System for nuclear area and nuclear/cytoplasmic ratio. Distribution of measured parameters among categories was analyzed by the Kruskal-Wallis test. RESULTS: During the study period, only the PSCSR categories "benign", "atypical" and "malignant" were recorded. A significant difference in distribution of nuclear/cytoplasmic ratio was seen between the "benign" and "atypical" categories but not between the "atypical" and "malignant" categories. The "atypical" category appeared to be bi-modal indicating that it could be divided into two categories, "atypical" and "suspicious for malignancy". CONCLUSIONS: The categories "atypical" and "suspicious for malignancy" served to divide the spectrum of cytomorphologic changes between "benign" and "malignant" into clinically useful groups. The use of these categories is supported by cytomorphometric analysis of bronchial brushing specimens.

12.
Int J Pharm ; : 120671, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33961957

RESUMEN

The pentose phosphate pathway (PPP) plays a critical role by providing ribulose-5-phosphate (Ru5P) and NADPH for nucleotide synthesis and reduction energy, respectively. Accordingly, blocking the PPP process may be an effective strategy for enhancing oxidation therapy and inhibiting cell replication. Here, we designed a novel reduction-responsive PEGylated prodrug and constructed nanoparticles PsD@CPT to simultaneously deliver a PPP blocker, dehydroepiandrosterone (DHEA), and chemotherapeutic camptothecin (CPT) to integrate amplification of oxidation therapy and enhance cell replication inhibition. Following cellular uptake, DHEA and CPT were released from PsD@CPT in the presence of high glutathione (GSH) levels. As expected, DHEA-mediated reduction level decreases and CPT-induced oxidation level increases synergistically, breaking the redox balance to aggravate cancer oxidative stress. In addition, suppressing nucleotide synthesis by DHEA through the reduction of Ru5P and blocking DNA replication by CPT further motivates a synergistic inhibition effect on tumor cell proliferation. The results showed that PsD@CPT featuring multimodal treatment has satisfactory antitumor activity both in vitro and in vivo. This study provides a new tumor treatment strategy, which combines the amplification of oxidative stress and enhancement of inhibition of cell proliferation based on inhibition of the PPP process.

13.
Sci Rep ; 11(1): 9436, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33941823

RESUMEN

Average biodegradation rate of newly filled municipal solid waste (MSW) in landfills is relatively fast, and the landfill gas produced by the new MSW biodegradation can cause great variations in gas pressure. To predict the gas pressure distribution in the MSW layer, a one-dimensional gas transport model is established in this study. The following factors are considered in this model: (1) the variation of gas permeability with depth; (2) the anisotropy ratio of gas permeability; (3) the settlement caused by waste biodegradation. Furthermore, a single peak model for gas production is applied as the source term of gas production. The equation for settlement caused by waste biodegradation is presented, and the time of peak gas production rate is obtained by fitting the settlement of the newly filled layer. The stratification of the unsaturated and saturated regions is taken into account by distinguishing the difference in gas saturation. The layering of the new and old waste layers is considered by distinguishing the difference in the length of time that waste has been degraded to produce gas. Based on the method of numerical calculation, the gas pressure distribution in the landfill with layered new and old MSW is well simulated. The position where the maximum gas pressure occurs is found. The sensitivity analysis shows that the influence of the anisotropy ratio on gas pressure distribution is more significant.

14.
Reprod Sci ; 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33959891

RESUMEN

The self-renewal of spermatogonial cells (SCs) provides the foundation for life-long spermatogenesis. To date, only a few growth factors have been used for the culture of SCs in vitro, and how to enhance proliferation capacity of SCs in vitro needs further research. This study aimed to explore the effects of periostin (POSTN) on the proliferation of human SCs. GC-1 spg cells were cultured in a medium with POSTN, cell proliferation was evaluated by MTS analysis and EdU assay, and the Wnt/ß-catenin signaling pathway was examined. Thereafter, the proliferations of human SC were detected using immunofluorescence and RT-PCR. In this study, we found that CM secreted by human amniotic mesenchymal stem cells (hAMSCs) could enhance the proliferation capacity of mouse GC-1 spg cells. Label-free mass spectrometry and ELISA analysis demonstrated that high level of POSTN was secreted by hAMSCs. MTS and EdU staining showed that POSTN increased GC-1 spg cell proliferation, whereas CM from POSTN-silenced hAMSCs suppressed cell proliferation capacity. Then POSTN was found to activate the Wnt/ß-catenin signaling pathway to regulate the proliferation of GC-1 spg cells. XAV-939, a Wnt/ß-catenin inhibitor, partially reversed the effects of POSTN on GC-1 spg cell proliferation. We then analyzed human SCs and found that POSTN promoted human SC proliferation in vitro. These findings provide insights regarding the role of POSTN in regulating SC proliferation via the Wnt/ß-catenin signaling pathway and suggest that POSTN may serve as a cytokine for male infertility therapy.

15.
Plant Biotechnol J ; 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33960617

RESUMEN

Oligonucleotide (oligo)-fluorescence in situ hybridization (FISH) has rapidly becoming the new generation of FISH technique in plant molecular cytogenetics research. Genome-scale identification of single copy oligos is the foundation of successful oligo-FISH experiments. Here, we introduce Chorus2, a software that is developed specifically for oligo selection. We demonstrate that Chorus2 is highly effective to remove all repetitive elements in selection of single copy oligos, which is critical for the development of successful FISH probes. Chorus2 is more effective than Chorus, the original version of the pipeline, and OligoMiner for repeat removal. Chorus2 allows to select oligos that are conserved among related species, which extends the usage of oligo-FISH probes among phylogenetically related plant species. We also implemented a new function in Chorus2 that allows development of FISH probes from plant species without an assembled genome. We anticipate that Chorus2 can be used in plants as well as in mammalian and other non-plant species. Chorus2 will broadly facilitate the design of FISH probes for various types of application in molecular cytogenetics research.

16.
Org Lett ; 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33970650

RESUMEN

Transition metal catalyzed dual C-H activation and annulation with alkynes was an attractive protocol to construct polycyclic π-extended structures. However, most of them were dominated by noble metal catalysts. Disclosed herein was the study of base-metal Ni-catalysis for dual C-H annulation of N-aromatic imidazole, which produced a range of desired polycyclic aza-quinolines in 48-95% yields. The use of bifunctional phosphine oxide ligand proved to be critical for success.

17.
J Appl Toxicol ; 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33973249

RESUMEN

Quantum dots (QDs), due to their superior luminous properties, have been proven to be a very promising biological probe, which can be used as a candidate material for clinical applications. The toxicity of QDs in the environment and biological systems has caused widespread concern in the nanosphere, but their immune toxicity and their impact on the immune system are still relatively unknown. At present, the research on the toxicity of QDs is mainly focused on in vitro models, but few have systematically evaluated their adverse effects on target organs. Animal studies have shown that QDs can be accumulated in various organs due to their main exposure routes, thereby posing a potential threat to major organs. This review briefly describes general characteristics and the wide medical applications of QDs and focuses on the adverse effects of QDs on major target organs, such as liver, lung, kidney, brain, and spleen, after acute and chronic exposure. QDs mainly cause changes in the corresponding indicators of target organs, such as oxidative damage, and in severe cases cause hyperemia, tissue necrosis, and even death. In addition to causing direct damage to target organs, QDs can also cause a large number of immune cells to accumulate and cause inflammatory reactions when causing damage to other major organs. Whether it is to avoid the risk of people contacting QDs in production and life, or to realize the clinical applications of QDs, is very essential to conduct systematic in vivo toxicity assessment of QDs.

18.
Dalton Trans ; 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-33973588

RESUMEN

Density functional theory (DFT) calculation has been used to reveal the mechanism of the Pd-catalyzed disilylation reaction of aryl halides. The DFT calculations indicate that the reaction starts with the oxidative addition of the C-I bond to the Pd(0) catalyst. Concerted metalation-deprotonation (CMD) can then generate a five-membered palladacycle. Insertion of Pd(ii) into the Si-Si bond in disilane followed by two sequential steps of reductive eliminations yields the disilylation product and regenerates the Pd(0) catalyst. According to the NPA charge analysis along the reaction coordinates, the formal oxidative addition of the Si-Si bond to palladium could be considered as the insertion of palladium into the Si-Si bond. However, the conventional oxidative addition of the C-I bond to palladium is exactly an oxidation process with the electron transfer from the palladium atom to the C-I bond. Therefore, electron rich Pd(0) is beneficial for the oxidation process, and Pd(ii) prone to acquire electrons is beneficial for the insertion process.

19.
Bone Joint J ; 103-B(5): 991-998, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33934653

RESUMEN

AIMS: The objective of this study was to evaluate the clinical and radiological outcomes of patients younger than six months of age with developmental dysplasia of the hip (DDH) managed by either a Pavlik harness or Tübingen hip flexion splint. METHODS: Records of 251 consecutive infants with a mean age of 89 days (SD 47), diagnosed with DDH between January 2015 and December 2018, were retrospectively reviewed. Inclusion criteria for patients with DDH were: younger than 180 days at the time of diagnosis; ultrasound Graf classification of IIc or greater; treatment by Pavlik harness or Tübingen splint; and no prior treatment history. All patients underwent hip ultrasound every seven days during the first three weeks of treatment and subsequently every three to four weeks until completion of treatment. If no signs of improvement were found after three weeks, the Pavlik harness or Tübingen splint was discontinued. Statistical analysis was performed. RESULTS: The study included 251 patients with Graf grades IIc to IV in 18 males and 233 females with DDH. Mean follow-up time was 22 months (SD 10). A total of 116 hips were graded as Graf IIc (39.1%), nine as grade D (3.0%), 100 as grade III (33.7%), and 72 as grade IV (24.2%). There were 109 patients (128 hips) in the Pavlik group and 142 patients (169 hips) in the Tübingen group (p = 0.227). The Tübingen group showed a 69.8% success rate in Graf III and Graf IV hips while the success rate was significantly lower in the Pavlik group, 53.9% (p = 0.033). For infants older than three months of age, the Tübingen group showed a 71.4% success rate, and the Pavlik group a 54.4% success rate (p = 0.047). CONCLUSION: The Tübingen splint should be the preferred treatment option for children older than three months, and for those with severe forms of DDH such as Graf grade III and IV, who are younger than six months at time of diagnosis. The Tübingen hip flexion splint is a valid alternative to the Pavlik harness for older infants and those with more severe DDH. Cite this article: Bone Joint J 2021;103-B(5):991-998.


Asunto(s)
Luxación Congénita de la Cadera/terapia , Aparatos Ortopédicos , Férulas (Fijadores) , Femenino , Luxación Congénita de la Cadera/clasificación , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos
20.
Med Res Rev ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33948974

RESUMEN

Endometriosis (EM) is defined as endometrial tissues found outside the uterus. Growth and development of endometriotic cells in ectopic sites can be promoted via multiple pathways, including MAPK/MEK/ERK, PI3K/Akt/mTOR, NF-κB, Rho/ROCK, reactive oxidative stress, tumor necrosis factor, transforming growth factor-ß, Wnt/ß-catenin, vascular endothelial growth factor, estrogen, and cytokines. The underlying pathophysiological mechanisms include proliferation, apoptosis, autophagy, migration, invasion, fibrosis, angiogenesis, oxidative stress, inflammation, and immune escape. Current medical treatments for EM are mainly hormonal and symptomatic, and thus the development of new, effective, and safe pharmaceuticals targeting specific molecular and signaling pathways is needed. Here, we systematically reviewed the literature focused on pharmaceuticals that specifically target the molecular and signaling pathways involved in the pathophysiology of EM. Potential drug targets, their upstream and downstream molecules with key aberrant signaling, and the regulatory mechanisms promoting the growth and development of endometriotic cells and tissues were discussed. Hormonal pharmaceuticals, including melatonin, exerts proapoptotic via regulating matrix metallopeptidase activity while nonhormonal pharmaceutical sorafenib exerts antiproliferative effect via MAPK/ERK pathway and antiangiogenesis activity via VEGF/VEGFR pathway. N-acetyl cysteine, curcumin, and ginsenoside exert antioxidant and anti-inflammatory effects via radical scavenging activity. Natural products have high efficacy with minimal side effects; for example, resveratrol and epigallocatechin gallate have multiple targets and provide synergistic efficacy to resolve the complexity of the pathophysiology of EM, showing promising efficacy in treating EM. Although new medical treatments are currently being developed, more detailed pharmacological studies and large sample size clinical trials are needed to confirm the efficacy and safety of these treatments in the near future.

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