Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int Urol Nephrol ; 56(4): 1307-1313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38044410

RESUMO

PURPOSE: Renal cysts are typically a benign condition, and parapelvic cysts are a type of renal cyst that occur adjacent to the renal pelvis or renal sinus. Parapelvic cysts can increase the risk for injury to adjacent organs or urine leakage during laparoscopic surgery. Flexible ureteroscopes with laser assistance were used to make internal incisions in cysts. Perioperative outcomes of this method were compared with those of laparoscopic surgery. METHODS: Eight-three patients, who underwent surgical treatment for renal cysts at the authors' medical center between January 2019 and June 2022, were evaluated. Two patients were excluded because they originally opted for RIRS but subsequently converted to laparoscopic surgery. Patients were divided into 2 groups based on surgery type: laparoscopic; and RIRS for internal incision. Outcomes in both groups were analyzed. RESULTS: Of the 81 patients analyzed, 60 [74% (group 1)] underwent laparoscopic surgery and 21 [26% (group 2)] underwent RIRS for internal incision. The median operative durations for groups 1 and 2 were 87 and 56 min, respectively (p < 0.001). Relative to RIRS, laparoscopic surgery resulted in greater postoperative painkiller use (laparoscopic surgery versus [vs.] RIRS, 43% vs. 19%; p = 0.047). The median length of hospital stay was 2 and 1 days, respectively (p < 0.001). CONCLUSIONS: RIRS demonstrated several advantages over laparoscopic surgery for the internal incision of parapelvic cysts, including shorter operative duration, shorter hospital stay, and less postoperative pain control. These findings may guide the selection of appropriate surgical approaches for patients with renal cysts.


Assuntos
Cistos , Cálculos Renais , Doenças Renais Císticas , Neoplasias Renais , Laparoscopia , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Ureteroscópios , Pelve Renal/cirurgia , Doenças Renais Císticas/cirurgia , Neoplasias Renais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Cálculos Renais/cirurgia
2.
Biomimetics (Basel) ; 8(8)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38132525

RESUMO

Inspired by periodically aligned micro/nanostructures on biological surfaces, researchers have been fabricating biomimetic structures with superior performance. As a promising and versatile tool, an ultrafast laser combined with other forms of processing technology has been utilized to manufacture functional structures, e.g., the biomimetic subwavelength structures to restrain the surface Fresnel reflectance. In this review paper, we interpret the biomimetic mechanism of antireflective subwavelength structures (ARSSs) for high-transmission windows. Recent advances in the fabrication of ARSSs with an ultrafast laser are summarized and introduced. The limitations and challenges of laser processing technology are discussed, and the future prospects for advancement are outlined, too.

3.
Adv Sci (Weinh) ; 10(30): e2304282, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37632709

RESUMO

Electrophilic addition reaction to alkynes is of fundamental importance in organic chemistry, yet the regiocontrol when reacting with unsymmetrical 1,2-dialkyl substituted alkynes is often problematic. Herein, it is demonstrated that the rarely recognized ß-boron effect can confer a high level of site-selectivity in several alkyne electrophilic addition reactions. A broad range of highly functionalized and complex organoborons are thus formed under simple reaction conditions starting from propargylic MIDA (N-methyliminodiacetic acid) boronates. These products are demonstrated to be valuable building blocks in organic synthesis. In addition to the regiocontrol, this study also observes a drastic rate enhancement upon B(MIDA) substitution. Theoretical calculation reveals that the highest occupied molecular obital (HOMO) energy level of propargylic B(MIDA) is significantly raised by 0.3 eV, and the preferential electrophilic addition to the γ position is due to its higher HOMO orbital coefficient and more negative natural bond orbital (NBO) charge compared to the ß position. This study demonstrates the potential of utilizing the ß-boron effect in stereoelectronic control of chemical transformations, which can inspire further research in this area.

4.
Front Plant Sci ; 14: 1102855, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035048

RESUMO

Reservoir operation is an important part of basin water resources management. The rational use of reservoir operation scheme can not only enhance the capacity of flood control and disaster reduction in the basin, but also improve the efficiency of water use and give full play to the comprehensive role the reservoir. The conventional decision-making method of reservoir operation scheme is computationally large, subjectivity and difficult to capture the nonlinear relationship. To solve these problems, this paper proposes a reservoir operation scheme decision-making model IWGAN-IWOA-CNN based on artificial intelligence and deep learning technology. In view of the lack of data in the original reservoir operation scheme and the limited improvement of data characteristics by the traditional data augmentation algorithm, an improved generative adversarial network algorithm (IWGAN) is proposed. IWGAN uses the loss function which integrates Wasserstein distance, gradient penalty and difference item, and dynamically adds random noise in the process of model training. The whale optimization algorithm is improved by introducing Logistic chaotic mapping to initialize population, non-linear convergence factor and adaptive weights, and Levy flight perturbation strategy. The improved whale optimization algorithm (IWOA) is used to optimize hyperparameters of convolutional neural networks (CNN), so as to obtain the best parameters for model prediction. The experimental results show that the data generated by IWGAN has certain representation ability and high quality; IWOA has faster convergence speed, higher convergence accuracy and better stability; IWGAN-IWOA-CNN model has higher prediction accuracy and reliability of scheme selection.

5.
Org Lett ; 25(7): 1099-1103, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36790117

RESUMO

α-Boryl ketones are traditionally challenging targets in organic synthesis. Reported herein is a mild and metal-free synthesis of α-boryl ketones via the hydration or oxidation of N-methyliminodiacetyl boronate (B(MIDA))-decorated alkynes. A new hydration system comprised of AcCl and H2O in HFIP allows the hydration of arylethynyl B(MIDA)s at room temperature with decent functional group tolerance. An oxidative carbon deletion process of propargylic B(MIDA)s is also developed for the synthesis of aliphatic α-boryl ketones. An intriguing ß-boron effect was observed to account for the unique site- and chemoselectivities. The application of the products in the synthesis of borylated heterocycles was demonstrated.

6.
Molecules ; 28(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838705

RESUMO

Combretastatin A-4 (CA-4) is a potent tubulin polymerisation inhibitor. However, the clinical application of CA-4 is limited owing to its low aqueous solubility and the easy conversion of the olefin double bond from the more active cis- to the less active trans-configuration. Several structural modifications were investigated to improve the solubility of CA-4 derivatives. Among the compounds we synthesized, the kinetic solubility assay revealed that the solubility of compounds containing a piperazine ring increased the most, and the solubility of compounds 12a1, 12a2, 15 and 18 was increased 230-2494 times compared with that of the control compound (Z)-3-(4-aminophenyl)-2-(3,4,5-trimethoxyphenyl)acrylonitrile (9a). In addition, these synthesised stilbene nitriles had high anticancer cell (AGS, BEL-7402, MCF-7, and HCT-116) selectivity over L-02 and MCF-10A normal cells while maintaining micromolar activity against cancer cells. The most cytotoxic compound is 9a, and the IC50 value is 20 nM against HCT-116 cancer cells. Preliminary studies indicated that compound 12a1 had excellent plasma stability and moderate binding to rat plasma proteins, suggesting it is a promising lead compound for the development of an anticancer agent.


Assuntos
Antineoplásicos , Estilbenos , Antineoplásicos/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Solubilidade , Estilbenos/química , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia , Humanos , Linhagem Celular Tumoral
7.
ACS Appl Mater Interfaces ; 15(9): 12109-12118, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36813758

RESUMO

The charge transfer between the donor and acceptor determines the photogenerated carrier density in organic solar cells. However, a fundamental understanding regarding the charge transfer at donor/acceptor interfaces with high-density traps has not been fully addressed. Herein, a general correlation between trap densities and charge transfer dynamics is established by adopting a series of high-efficiency organic photovoltaic blends. It is found that the electron transfer rates are reduced with increased trap densities, while the hole transfer rates are independent of trap states. The local charges captured by traps can induce potential barrier formation around recombination centers, leading to the suppression of electron transfer. For the hole transfer process, the thermal energy provides a sufficient driving force, which ensures an efficient transfer rate. As a result, a 17.18% efficiency is obtained for PM6:BTP-eC9-based devices with the lowest interfacial trap densities. This work highlights the importance of interfacial traps in charge transfer processes and proposes an underlying insight into the charge transfer mechanism at nonideal interfaces in organic heterostructures.

8.
Clin Med Insights Oncol ; 17: 11795549221147993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36685988

RESUMO

Background: Assessing the prognosis preoperatively in patients with upper tract urothelial carcinoma (UTUC) remains a challenge for urologists. Gross hematuria (GH) and flank pain (FP) are the 2 most common and easily perceived symptoms of UTUC. Therefore, we aimed to investigate the prognostic values of GH and FP in patients with UTUC after undergoing radical nephroureterectomy (RNU). Methods: This article retrospectively analyzed 179 patients with UTUC who underwent RNU and examined the associations between the FP, GH, and long-term survival. After dividing patients into 4 subgroups (presenting as GH without FP, FP without GH, no FP and GH, FP with GH), we focused on the prognostic values of the 4 subgroups using univariate and multivariate analyses. We then proposed a risk stratification model for UTUC based on the independent prognostic factors for cancer-specific survival (CSS) with external validation (146 additional UTUC patients formed the validation cohort). Results: Patients with FP had worse oncological outcomes than those without FP (P < .05). After dividing the 179 patients into 4 subgroups, the "FP without GH" subgroup suffered the worst oncological outcomes (P < .001). The Cox multivariate regression analysis showed that "FP without GH" (P < .001), tumor multifocality (P = .005), and pathological stage (P = .004) were independent prognostic factors for CSS. Good performance of the risk stratification model was achieved in both the training and external validation cohorts. Conclusion: The presence of "flank pain without gross hematuria" was one of the independent risk factors of CSS and OS besides the pathological stage and tumor multifocality. To our knowledge, this is the first study that adding complaint to risk stratification model in UTUC.

9.
J Environ Manage ; 324: 116209, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155083

RESUMO

External-soil spray seeding (ESSS) is a method often used for the ecological restoration of bare rock slopes. However, the direct use of ESSS is normally less satisfactory due to the erosion of sprayed soil and low survival rate of the plants on rock slopes. This study proposes a novel approach to addressing this issue through the combined use of ESSS with polyvinyl acetate (PVA) based soil stabilization. The PVA solutions are added to the soil to stabilize soil and improve soil strength while possessing high water and nutrient retention favorable for plant growth. A series of experimental tests on the mechanical properties, water stability, erosion resistance, water retention, and plant growth of the PVA-stabilized soil were conducted to assess the efficacy of the proposed method. The results showed that the proposed method could be promising for rock slope ecological restoration. A proper curing time (e.g., >3 days) was required to achieve beneficial effects of PVA on the soil properties. A shorter curing time would otherwise result in the decrease in the strength with the increased PVA content. It was found that the optimum PVA content was 3% for achieving the maximum water stability, erosion resistance, water retention, and plant growth. The cohesion increased by up to 50% and the internal friction angle increased by 3.5° compared to the natural soil. The disintegration rate of the stabilized soil was generally < 3e-3%/min. The maximum reduction in erosion was up to 83% when the PVA content ≥3%. The mechanisms behind the findings are also discussed.


Assuntos
Polivinil , Solo , Plantas , Água
10.
World J Gastroenterol ; 28(34): 5086-5092, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36160650

RESUMO

BACKGROUND: Gastrointestinal (GI) lipomas are benign submucosal tumors of mature adipocytes that arise mainly in the colon and stomach, sometimes in the ileum and jejunum, and rarely in the duodenum. Patients with symptomatic lipomas require endoscopic or surgical treatment. Spontaneous expulsion of lipomas after biopsy is a rare condition that has limited case reports. CASE SUMMARY: A 56-year-old man presented to our hospital with intermittent postprandial epigastric fullness. Esophagogastroduodenoscopy (EGD) revealed a 10-mm soft yellowish submucosal lesion with the "pillow sign," located in the second portion of duodenum. Endoscopic ultrasonography (EUS) using a 12-MHz catheter probe showed a hyperechoic, homogenous, and round solid lesion (OLYMPUS EUS EU-ME2, UM-DP12-25R, 12-MHz radial miniprobe, Olympus Corporation, Tokyo, Japan). Deep biopsy was performed using the bite-on-bite technique with forceps. Histological examination was compatible with submucosal lipoma. The lesion spontaneously expelled 12 d after the biopsy. Follow-up EUS performed after 2 mo confirmed this condition. CONCLUSION: Deep biopsy could lead to spontaneous GI lipoma expulsion. This might be the first step in lipoma diagnosis and treatment.


Assuntos
Lipoma , Biópsia , Duodeno/diagnóstico por imagem , Duodeno/patologia , Endossonografia , Humanos , Lipoma/patologia , Masculino , Pessoa de Meia-Idade , Estômago/patologia
11.
J Am Chem Soc ; 144(31): 14380-14387, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35895901

RESUMO

For internal alkenes possessing two or more sets of electronically and sterically similar allylic protons, the site-selectivity for allylic C-H functionalization is fundamentally challenging. Previously, the negative inductive effect from an electronegative atom has been demonstrated to be effective for several inspiring regioselective C-H functionalization reactions. Yet, the use of an electropositive atom for a similar purpose remains to be developed. α-Aminoboronic acids and their derivatives have found widespread applications. Their current syntheses rely heavily on functional group manipulations. Herein we report a boryl-directed intermolecular C-H amination of allyl N-methyliminodiacetyl boronates (B(MIDA)s) and propargylic B(MIDA)s to give α-amino boronates with an exceptionally high level of site-selectivities (up to 300:1). A wide variety of highly functionalized secondary and tertiary α-amino boronates are formed in generally good to excellent yields, thanks to the mildness of the reaction conditions. The unsaturated double and triple bonds within the product leave room for further decorations. Mechanistic studies reveal that the key stabilization effect of the B(MIDA) moiety on its adjacent developing positive charge is responsible for the high site-selectivity and that a closed transition state might be involved, as the reaction is fully stereoretentive. An activation effect of B(MIDA) is also found.


Assuntos
Alcenos , Prótons , Alcenos/química , Aminação , Catálise
12.
Bot Stud ; 63(1): 21, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821129

RESUMO

BACKGROUND: Blumea plants are widely distributed in the tropical areas of Asia, Africa, and Australia, especially tropical Asia. Limited studies left the taxonomy and infrageneric phylogeny of Blumea insubstantial. Here, a new species, Blumea chishangensis S. W. Chung, Z. H. Chen, S. H. Liu & W. J. Huang, from Taiwan is described, and an extended phylogeny is reconstructed to provide new perceptions of Blumea evolution. RESULTS: The new species is distinguished from B. hieraciifolia by the following features: leaf blade sparsely pilose or glabrescent (vs. silky villous), the leaves margins regularly remote mucronulate (vs. double serrate or dentate), capitula pedicelled (vs. capitula sessile or subsessile), and leaves basal rosette or sub-basal rosette and a few cauline (vs. mostly cauline). Phylogenetic analysis based on the ITS, trnL-trnF, and trnH-psbA regions places the new species in the subclade II in B. lacera clade and shows a close relationship with B. axillaris and B. oxyodonta. A key to Blumea species in Taiwan and the studied species in the subclade II is provided. Moreover, the evolutionary inferences of B. conspicua, B. linearis, and B. sinuata are first reported here. The paraphyly of B. formosana and B. sinuata are also revealed for the first time. CONCLUSIONS: Both morphological and molecular data support that B. chishangensis is a new species. Our phylogeny highlights the need for further taxonomic and evolutionary studies on Blumea.

13.
BMC Urol ; 22(1): 93, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35773639

RESUMO

BACKGROUND: Staghorn stones require surgical treatment to prevent serious complications. Multitract percutaneous nephrolithotomy (PNL) causes great renal parenchymal injury and blood loss. One-stage endoscopic combined intrarenal surgery (ECIRS) entails the combined use of antegrade nephroscope and retrograde flexible ureteroscope to clear the staghorn stone, which may overcome the limitations of multitract PNL. We aimed to compare the perioperative outcomes of mini ECIRS and multitract minimally invasive PNL in staghorn stone management. METHODS: This was a retrospective single-center study of patients with staghorn stones who underwent ECIRS (n = 17) or multitract minimally invasive PNL (n = 17) between January 2018 and September 2021. RESULTS: There was a significant between-group difference with respect to Guy's stone score. Stone size, stone burden (ECIRS group, 21.41 cm3; multitract minimally invasive PNL group, 20.88 cm3 [P = 0.94]), and degree of hydronephrosis were comparable in the two groups. There was no significant between-group difference with respect to one-step or final stone-free rates. The mean operative time was also not significantly different between the groups (ECIRS group, 140 min; multitract minimally invasive PNL group, 183 min [P = 0.63]). ECIRS was associated with significantly lesser postoperative pain (visual analog scale; ECIRS group: 0; multitract minimally invasive PNL group: 2.7 [P < 0.001]). Hemoglobin loss, postoperative blood transfusion rate, complications, and length of hospital stay were comparable in the two groups. CONCLUSION: Both mini ECIRS and multitract minimally invasive PNL were effective and safe for the management of renal staghorn stones with comparable operation time and stone-free rate, and complications. ECIRS was associated with less severe postoperative pain.


Assuntos
Cálculos Renais , Nefrolitotomia Percutânea , Nefrostomia Percutânea , Cálculos Coraliformes , Humanos , Rim , Cálculos Renais/cirurgia , Nefrolitotomia Percutânea/métodos , Nefrostomia Percutânea/métodos , Dor Pós-Operatória , Estudos Retrospectivos , Cálculos Coraliformes/cirurgia , Resultado do Tratamento , Ureteroscopia/métodos
14.
Front Cell Dev Biol ; 10: 796227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35517504

RESUMO

Osteoporosis, characterized by the destruction of bone resorption and bone formation, is a serious disease that endangers human health. Osteoporosis prevention and treatment has become one of the important research contents in the field of medicine. Acacetin, a natural flavonoid compound, could promote osteoblast differentiation, and inhibit osteoclast formation in vitro. However, the mechanisms of acacetin on osteoclast differentiation and type H vessel formation, as well as the effect of preventing bone loss, remain unclear. Here, we firstly used primary bone marrow derived macrophages (BMMs), endothelial progenitor cells (EPCs), and ovariectomized (OVX) mice to explore the function of acacetin on bone remodeling and H type vessel formation. In this study, we found that acacetin inhibits osteoclast formation and bone resorption of BMMs induced by the macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL) in a concentration of 20 µM without exerting cytotoxic effects. It was accompanied by downregulation of osteoclast differentiation marker genes (Ctsk, Acp5, and Mmp9) and cell fusion genes (CD9, CD47, Atp6v0d2, Dc-stamp, and Oc-stamp). Moreover, acacetin disrupted actin ring formation and extracellular acidification in osteoclasts. Mechanistic analysis revealed that acacetin not only inhibits the expression of the major transcription factor NFATc1 and NF-κB during RANKL-induced osteoclast formation, but also suppresses RANKL-induced the phosphorylation of Akt, GSK3ß, IκBα, and p65. Additionally, acacetin enhanced the ability of M-CSF and RANKL-stimulated BMMs to promote angiogenesis and migration of EPCs. We further established that, in vivo, acacetin increased trabecular bone mass, decreased the number of osteoclasts, and showed more type H vessels in OVX mice. These data demonstrate that acacetin prevents OVX-induced bone loss in mice through inhibition of osteoclast function and promotion of type H vessel formation via Akt/GSK3ß and NF-κB signalling pathway, suggesting that acacetin may be a novel therapeutic agent for the treatment of osteoporosis.

15.
Opt Express ; 30(6): 9521-9533, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299378

RESUMO

Liquid crystals (LCs) have been a vital component of modern communication and photonic technologies. However, traditional LC alignment on polyimide (PI) requires mechanically rubbing treatment to control LC orientation, suffering from dust particles, surface damage, and electrostatic charges. In this paper, LC alignment on organic single-crystal rubrene (SCR) has been studied and used to fabricate rubbing-free LC devices. A rubrene/toluene solution is spin-coated on the indium-tin-oxide (ITO) substrate and transformed thereafter to the orthorhombic SCR after annealing. Experimental result reveals that SCR-based LC cell has a homogeneous alignment geometry, the pretilt angle of LCs is low and the orientation of LCs is determined with capillary filling action of LCs. LC alignment on SCR performs a wider thermal tolerance than that on PI by virtue of the strong anchoring nature of LCs on SCR due to van der Waals and π-π electron stacking interactions between the rubrene and LCs. SCR-based LC cell performs a lower operation voltage, faster response time, and higher voltage holding ratio than the traditional PI-based LC cell. Organic SCR enables to play a role as weakly conductive alignment layer without rubbing treatment and offers versatile function to develop novel LC devices.

16.
J Oncol ; 2022: 5680353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35096062

RESUMO

Bladder cancer is the second-most common malignancy in the urogenital system and the most common in men. However, our understanding of the driving mechanisms of bladder cancer remains incomplete. The forkhead box (FOX) family of transcription factors is implicated in urogenital development and bladder malignancies. Many exosomal microRNAs have been identified as regulators and mediators of the expression of FOX, including the expression of FOXC1. miR-4792 has been known as a tumor miRNA suppressor. However, the function of miR-4792/FOXC1 signaling in bladder cancer development remains unknown. Here, we studied the role of miR-4792/FOXC1 signaling in bladder cancer by using multiple bladder cancer cell lines and bladder cancer mouse models through in vitro and in vivo approaches. We showed that FOXC1 is highly expressed in multiple bladder cancer cell lines and bladder tumor tissues. The knockdown of FOXC1 expression in bladder cancer cell lines decreases c-Myc expression levels, retards cell growth, and reduces aerobic glycolysis (also known as the Warburg effect) and lactic acid content. By contrast, the overexpression of FOXC1 elicits the opposite effects. FOXC1-downregulated bladder cancer cells form significantly smaller tumors in vivo. The inhibition of c-Myc reverses the effects of FOXC1 overexpression and leads to reduced cell proliferation, aerobic glycolysis, and lactic acid content. miR-4792 expression is downregulated in bladder tumor tissues. miR-4792 exposure to bladder cancer cells reduces the expression levels of FOXC1 and c-Myc, slows down cell growth, and decreases aerobic glycolysis and lactic acid content. However, the enhanced miR-4792 expression elicits opposite effects. These findings provided the first evidence that the exosome-mediated delivery of miR-4792 could play an important role in bladder cancer development through the downregulation of FOXC1 and c-Myc, which further inhibited aerobic glycolysis and lactic acid content.

17.
World J Clin Cases ; 10(36): 13458-13466, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36683632

RESUMO

BACKGROUND: Hoffa's fracture is a coronal-oriented fracture of the femoral condyle. It is rarely observed in pediatric patients that isolated coronal fracture of the medial femoral condyle accompanies an intact lateral femoral condyle. Only a few cases involving Hoffa's fracture of the medial femoral condyle have been reported in patients with undeveloped skeletons. Such a fracture cannot be observed by routine imaging examinations, thus resulting in possible misdiagnosis and further treatment challenges. CASE SUMMARY: A 5-year-old boy with Hoffa's fracture of the medial femoral condyle suffered from right knee pain and severe swelling after being hit by a heavy object. The patient was misdiagnosed and initially treated in a local primary healthcare center. No improvement in his right knee's extension was observed following conservative treatment for 2 wk. The patient was transferred to our hospital, re-diagnosed using arthroscopy, and underwent open reduction and internal fixation. The therapeutic outcome was satisfactory with the screws removed 7 mo after fixation. At the final follow-up of 40 mo, the range of motion in the knee had recovered. There was no varus-valgus instability. CONCLUSION: Hoffa's fracture is rarely seen in children aged 5 years, let alone in the medial condyle, and can easily be misdiagnosed due to limited physical and imaging examinations. Suspected Hoffa's fracture in preschool children should be confirmed based on arthroscopic findings. Open reduction and internal fixation should be performed to protect the articular surface and prevent long-term complications.

18.
Angew Chem Int Ed Engl ; 59(35): 15254-15259, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32394631

RESUMO

A novel strategy for asymmetric Shono-type oxidative cross-coupling has been developed by merging copper catalysis and electrochemistry, affording C1-alkynylated tetrahydroisoquinolines with good to excellent enantioselectivity. The use of TEMPO as a co-catalytic redox mediator is crucial not only for oxidizing a tetrahydroisoquinoline to an iminium ion species but also for decreasing the oxidation potential of the reaction. A novel bisoxazoline ligand is also reported.

19.
Ying Yong Sheng Tai Xue Bao ; 31(8): 2749-2758, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34494798

RESUMO

We investigated the effects of tea plantation age on soil microbial community structure and diversity with surface and subsurface soil samples (0-20 and 20-40 cm) from tea plantation at different ages (0, 20, 25, 38 and 48 years). We analyzed soil bacterial and fungal communities by terminal restriction fragment length polymorphism (T-RFLP) and real-time quantitative PCR techniques. The results showed that soil physicochemical properties changed significantly after planting tea. The contents of soil organic carbon, available nitrogen, and available phosphorus increased at first, and gradually decreased with the increases of tea plantation age. The contents of organic carbon and total nitrogen in the topsoil were significantly higher than those in the subsoil. Moreover, soil bacterial community composition varied across tea plantation age. Bacterial diversity index decreased with increasing tea plantation age. The composition and diversity of soil fungal communities did not show a clear relationship with the tea plantation age. Overall, soil bacterial communities was more sensitive to the tea plantation age than fungal communities. With the increases of tea plantation age, the ratio of soil fungi to bacteria showed increasing trend. Soil microbial community in the tea plantation changed from a "bacterial type" with low fungi/bacteria ratio (F/B) to a "fungal type" with high F/B.


Assuntos
Microbiota , Solo , Carbono/análise , Nitrogênio/análise , Microbiologia do Solo , Chá
20.
Huan Jing Ke Xue ; 41(1): 412-419, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854944

RESUMO

To explore the rate variation and contribution to N loss of denitrification and anaerobic ammonia oxidation (ANAMMOX) in the nitrogen migration process of farmland soils in southern China, we assess the physicochemical characteristics soil samples of different soil layers from farmland and different land use types (farmland, river channel, riparian zone, and lake sediment) in a wheat-rice rotation area of Wanshandang Lake. Illumina MiSeq sequencing and quantitative real-time polymerase chain reaction (qPCR) are used to investigate the microbial community composition and functional gene abundances of the samples. The potential denitrification and ANAMMOX rate (calculated by N2) of each sample was determined by an isotope culture experiment. It was demonstrated that the potential denitrification rate was significantly positively correlated with TOC, NH4+-N, and NO3--N (P<0.05), and with the abundances of nirS, nirK, and nosZ (P<0.05). The denitrification rate of surface soils was (11.51±1.04) nmol·(g·h)-1, which was significantly higher than other soil layers and other land use types (P<0.05). While the ANAMMOX rate in farmland soils was the highest in the 20-30 cm layer and reached (0.48±0.07) nmol·(g·h)-1. In addition, denitrification was the main cause of N loss in surface soils of the studied farmland, accounting for 91.9%-99.7% of overall loss, and ANAMMOX played an important role in the production of N2 in deep soils.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...