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1.
World J Surg Oncol ; 22(1): 120, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702816

RESUMEN

BACKGROUND: REBOA is a method used to manage bleeding during surgery involving sacropelvic tumors. Nevertheless, studies on the use of REBOA among elderly people are lacking. The aim of this research was to investigate the efficacy and safety of Zone III REBOA in patients aged more than 70 years. METHODS: A comparative study was conducted using case-control methods. A group of patients, referred to as Group A, who were younger than 70 years was identified and paired with a comparable group of patients, known as Group B, who were older than 70 years. Continuous monitoring of physiological parameters was conducted, and blood samples were collected at consistent intervals. RESULTS: Totally, 188 participants were enrolled and received REBOA. Among the 188 patients, seventeen were aged more than 70 years. By implementing REBOA, the average amount of blood loss was only 1427 ml. Experiments were also conducted to compare Group A and Group B. No notable differences were observed in terms of demographic variables, systolic blood pressure (SBP), arterial pH, lactate levels, blood creatinine levels, potassium levels, or calcium levels at baseline. Additionally, after the deflation of the REBOA, laboratory test results, which included arterial pH, lactate, potassium concentration, calcium concentration, and blood creatinine concentration, were not significantly different (P > 0.05). CONCLUSION: This study indicated that in selected patients aged more than 70 years can achieve satisfactory hemodynamic and metabolic stability with Zone III REBOA. LEVEL OF EVIDENCE: Therapeutic study, Level III.


Asunto(s)
Neoplasias Pélvicas , Humanos , Femenino , Masculino , Anciano , Estudios de Casos y Controles , Persona de Mediana Edad , Neoplasias Pélvicas/cirugía , Neoplasias Pélvicas/patología , Estudios de Seguimiento , Pronóstico , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Pérdida de Sangre Quirúrgica/prevención & control , Anciano de 80 o más Años , Adulto
2.
Front Bioeng Biotechnol ; 12: 1391298, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707499

RESUMEN

Background: After femoral oncological knee arthroplasty, some patients suffer from rotating axis fracture, which significantly impacts the life span of the rotating hinge knee (RHK) prosthesis. This research aimed to analyze the biomechanical response of anatomical gastrocnemius reconstruction and assess whether it could reduce the risk of rotating axis breakage by finite element (FE) analysis. Methods: A femur-prosthesis-tibia FE model was established using the data from CT scans. The mechanical properties of the RHK implant were quantitatively compared before and after gastrocnemius reconstruction at 6 angles: 10°, 20°, 30°, 40°, 50°, and 60°. Results: Our results showed that gastrocnemius reconstruction effectively altered the stress distribution around the rotating axis, considerably relieving the stress in the fracture-prone region. In addition, the peak stress in the rotating axis, bending axis, prosthesis stem, and femoral condyles decreased variably. Conclusion: In distal femoral resection knee arthroplasty, the rebuilding of gastrocnemius substantially improved the stress distribution within the prosthesis, thereby having the potential to reduce the risk of prosthetic fracture and prolong the overall durability of the prosthesis.

3.
Cancer Lett ; 591: 216902, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38641310

RESUMEN

Platelets have received growing attention for their roles in hematogenous tumor metastasis. However, the tumor-platelet interaction in osteosarcoma (OS) remains poorly understood. Here, using platelet-specific focal adhesion kinase (FAK)-deficient mice, we uncover a FAK-dependent F3/TGF-ß positive feedback loop in OS. Disruption of the feedback loop by inhibition of F3, TGF-ß, or FAK significantly suppresses OS progression. We demonstrate that OS F3 initiated the feedback loop by increasing platelet TGF-ß secretion, and platelet-derived TGF-ß promoted OS F3 expression in turn and modulated OS EMT process. Immunofluorescence results indicate platelet infiltration in OS niche and we verified it was mediated by platelet FAK. In addition, platelet FAK was proved to mediate platelet adhesion to OS cells, which was vital for the initiation of F3/TGF-ß feedback loop. Collectively, these findings provide a rationale for novel therapeutic strategies targeting tumor-platelet interplay in metastatic OS.

4.
Health Inf Sci Syst ; 12(1): 31, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38645838

RESUMEN

Early and accurate diagnosis of osteosarcomas (OS) is of great clinical significance, and machine learning (ML) based methods are increasingly adopted. However, current ML-based methods for osteosarcoma diagnosis consider only X-ray images, usually fail to generalize to new cases, and lack explainability. In this paper, we seek to explore the capability of deep learning models in diagnosing primary OS, with higher accuracy, explainability, and generality. Concretely, we analyze the added value of integrating the biochemical data, i.e., alkaline phosphatase (ALP) and lactate dehydrogenase (LDH), and design a model that incorporates the numerical features of ALP and LDH and the visual features of X-ray imaging through a late fusion approach in the feature space. We evaluate this model on real-world clinic data with 848 patients aged from 4 to 81. The experimental results reveal the effectiveness of incorporating ALP and LDH simultaneously in a late fusion approach, with the accuracy of the considered 2608 cases increased to 97.17%, compared to 94.35% in the baseline. Grad-CAM visualizations consistent with orthopedic specialists further justified the model's explainability.

5.
BMC Oral Health ; 24(1): 425, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582842

RESUMEN

BACKGROUND: Clinical scenarios frequently present challenges when patients exhibit asymmetrical mandibular atrophy. The dilemma arises: should we adhere to the conventional All-on-4 technique, or should we contemplate placing vertically oriented implants on the side with sufficient bone mass? This study aims to employ three-dimensional finite element analysis to simulate and explore the biomechanical advantages of each approach. METHODS: A finite element model, derived from computed tomography (CT) data, was utilized to simulate the nonhomogeneous features of the mandible. Three configurations-All-on-4, All-on-5-v and All-on-5-o were studied. Vertical and oblique forces of 200 N were applied unilaterally, and vertical force of 100 N was applied anteriorly to simulate different masticatory mechanisms. The maximum von Mises stresses on the implant and framework were recorded, as well as the maximum equivalent strain in the peri-implant bone. RESULTS: The maximum stress values for all designs were located at the neck of the distal implant, and the maximum strains in the bone tissue were located around the distal implant. The All-on-5-o and All-on-5-v models exhibited reduced stresses and strains compared to All-on-4, highlighting the potential benefits of the additional implant. There were no considerable differences in stresses and strains between the All-on-5-o and All-on-5-v groups. CONCLUSIONS: With the presence of adequate bone volume on one side and severe atrophy of the contralateral bone, while the "All-on-4 concept" is a viable approach, vertical implant placement optimizes the transfer of forces between components and tissues.


Asunto(s)
Implantes Dentales , Humanos , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Estrés Mecánico , Análisis del Estrés Dental/métodos , Prótesis Dental de Soporte Implantado , Mandíbula/diagnóstico por imagen , Atrofia
6.
3D Print Med ; 10(1): 15, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656431

RESUMEN

BACKGROUND: Inadequate surface matching, variation in the guide design, and soft tissue on the skeletal surface may make it difficult to accurately place the 3D-printed patient-specific instrument (PSI) exactly to the designated site, leading to decreased accuracy, or even errors. Consequently, we developed a novel 3D-printed PSI with fluoroscopy-guided positioning markers to enhance the accuracy of osteotomies in joint-preserving surgery. The current study was to compare whether the fluoroscopically calibrated PSI (FCPSI) can achieve better accuracy compared with freehand resection and conventional PSI (CPSI) resection. METHODS: Simulated joint-preserving surgery was conducted using nine synthetic left knee bone models. Osteotomies adjacent to the knee joint were designed to evaluate the accuracy at the epiphysis side. The experiment was divided into three groups: free-hand, conventional PSI (CPSI), and fluoroscopically Calibrated PSI (FCPSI). Post-resection CT scans were quantitatively analyzed. Analysis of variance (ANOVA) was used. RESULT: FCPSI improved the resection accuracy significantly. The mean location accuracy is 2.66 mm for FCPSI compared to 6.36 mm (P < 0.001) for freehand resection and 4.58 mm (P = 0.012) for CPSI. The mean average distance is 1.27 mm compared to 2.99 mm (p < 0.001) and 2.11 mm (p = 0.049). The mean absolute angle is 2.16° compared to 8.50° (p < 0.001) and 5.54° (p = 0.021). The mean depth angle is 1.41° compared to 8.10° (p < 0.001) and 5.32° (p = 0.012). However, there were no significant differences in the front angle compared to the freehand resection group (P = 0.055) and CPSI (P = 0.599) group. The location accuracy observed with FCPSI was maintained at 4 mm, while CPSI and freehand resection exhibited a maximum deviation of 8 mm. CONCLUSION: The fluoroscopically calibrated 3D-printed patient-specific instruments improve the accuracy of osteotomy during bone tumor resection adjacent to joint joints compared to conventional PSI and freehand resection. In conclusion, this novel 3D-printed PSI offers significant accuracy improvement in joint preserving surgery with a minimal increase in time and design costs.

7.
Acta Pharm Sin B ; 14(3): 1362-1379, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38486996

RESUMEN

Extracellular vesicles (EVs) have recently emerged as a promising delivery platform for CRISPR/Cas9 ribonucleoproteins (RNPs), owing to their ability to minimize off-target effects and immune responses. However, enhancements are required to boost the efficiency and safety of Cas9 RNP enrichment within EVs. In response, we employed the Fc/Spa interaction system, in which the human Fc domain was fused to the intracellular domain of PTGFRN-Δ687 and anchored to the EV membrane. Simultaneously, the B domain of the Spa protein was fused to the C domain of cargos such as Cre or spCas9. Due to the robust interaction between Fc and Spa, this method enriched nearly twice the amount of cargo within the EVs. EVs loaded with spCas9 RNP targeting the HSV1 genome exhibited significant inhibition of viral replication in vitro and in vivo. Moreover, following neuron-targeting peptide RVG modification, the in vivo dosage in neural tissues substantially increased, contributing to the clearance of the HSV1 virus in neural tissues and exhibiting a lower off-target efficiency. These findings establish a robust platform for efficient EV-based SpCas9 delivery, offering potential therapeutic advantages for HSV1 infections and other neurological disorders.

9.
Front Surg ; 11: 1279179, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505408

RESUMEN

Background: Surgical treatment of musculoskeletal tumors in the periacetabular region present extremely difficult due to the complex anatomy and need for reconstruction. Orthopedic surgeons face more difficulties in patients with neurological conditions, which can cause increased muscle tone, an elevated risk of fractures, and compromised bone quality. There is limited evidence regarding endoprosthetic reconstruction for periacetabular tumors in individuals with neurological disorders. Methods: We conducted a single-center retrospective study to examine the outcomes of patients with preexisting neurological conditions who underwent surgery to remove periacetabular tumors and who underwent endoprosthesis reconstruction. Clinical presentation, detailed neurological conditions, complications, and functional outcomes were studied. Results: Sixteen out of the 838 patients were identified (1.91%), with a mean follow-up time of 33 months. The primary neurological conditions encompassed Parkinson's disease, Alzheimer's disease, dementia, and cerebral ischemic stroke. Every patient was diagnosed with periacetabular lesions that were either primary or oligometastatic. They underwent tumor resection and subsequently received endoprosthetic reconstruction of the hemipelvis. Three patients developed metastasis lesions later, and two patients experienced tumor recurrence. Five cases experienced hip dislocation-one with periprosthetic fracture and one with surgical site infection. The position of the prosthetic rotating center was not correlated with dislocation. The reoperation rate was 31.25%. The cohort of patients all presented with more extended hospital stays and rehabilitation. In 3 patients, the general functional score was good, while in 6 patients, it was fair; in 7 patients, it was regarded as poor. The average MSTS93 score was 49.71%. Conclusion: Endoprosthetic reconstruction after periacetabular tumor resection is an effective way to eliminate tumors and salvage limbs. However, this group of patients has an increased likelihood of secondary surgery, complications, extended hospital stay, and no significant improvement in functional outcomes. Despite the diverse nature of the cohort, it is recommended to consider enhanced soft tissue reconstruction, supervised functional recovery and rehabilitation training.

10.
Adv Sci (Weinh) ; : e2310167, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502871

RESUMEN

Complete removal of all tumor tissue with a wide surgical margin is essential for the treatment of osteosarcoma (OS). However, it's difficult, sometimes impossible, to achieve due to the invisible small satellite lesions and blurry tumor boundaries. Besides, intraoperative frozen-section analysis of resection margins of OS is often restricted by the hard tissues around OS, which makes it impossible to know whether a negative margin is achieved. Any unresected small tumor residuals will lead to local recurrence and worse prognosis. Herein, based on the high expression of B7H3 in OS, a targeted probe B7H3-IRDye800CW is synthesized by conjugating anti-B7H3 antibody and IRDye800CW. B7H3-IRDye800CW can accurately label OS areas after intravenous administration, thereby helping surgeons identify and resect residual OS lesions (<2 mm) and lung metastatic lesions. The tumor-background ratio reaches 4.42 ± 1.77 at day 3. After incubating fresh human OS specimen with B7H3-IRDye800CW, it can specifically label the OS area and even the microinvasion area (confirmed by hematoxylin-eosin [HE] staining). The probe labeled area is consistent with the tumor area shown by magnetic resonance imaging and complete HE staining of the specimen. In summary, B7H3-IRDye800CW has translational potential in intraoperative resection guidance and rapid pathological diagnosis of OS.

11.
Adv Sci (Weinh) ; : e2400018, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502873

RESUMEN

Mix-dimensional heterojunctions (MDHJs) photodetectors (PDs) built from bulk and 2D materials are the research focus to develop hetero-integrated and multifunctional optoelectronic sensor systems. However, it is still an open issue for achieving multiple effects synergistic characteristics to boost sensitivity and enrich the prospect in artificial bionic systems. Herein, electrically tunable Te/WSe2 MDHJs phototransistors are constructed, and an ultralow dark current below 0.1 pA and a large on/off rectification ratio of 106 is achieved. Photoconductive, photovoltaic, and photo-thermoelectric conversions are simultaneously demonstrated by tuning the gate and bias. By these synergistic effects, responsivity and detectivity respectively reach 13.9 A W-1 and 1.37 × 1012 Jones with 400 times increment. The Te/WSe2 MDHJs PDs can function as artificial bionic visual systems due to the comparable response time to those of the human visual system and the presence of transient positive and negative response signals. This work offers an available strategy for intelligent optoelectronic devices with hetero-integration and multifunctions.

12.
BMC Cancer ; 24(1): 172, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310286

RESUMEN

BACKGROUND: Epithelioid sarcoma is a rare soft tissue sarcoma characterized by SMARCB1/INI1 deficiency. Much attention has been paid to the selective EZH2 inhibitor tazemetostat, where other systemic treatments are generally ignored. To explore alternative treatment options, we studied the effects of irinotecan-based chemotherapy in a series of epithelioid sarcoma patients. METHODS: We retrospectively reviewed data from patients with metastatic or unresectable epithelioid sarcoma at the Peking University People's Hospital treated with irinotecan (50 mg/m2/d d1-5 Q3W) in combination with Anlotinib (12 mg Qd, 2 weeks on and 1 week off) from July 2015 to November 2021. RESULTS: A total of 54 courses were administered. With a median follow up of 21.2 months (95% CI, 12.2, 68.1), the 5-year overall survival rate was 83.3%. Five of eight (62.5%) patients presented with unresectable localized lesions, including local tumor thrombosis and lymphatic metastasis. The other patients had unresectable pulmonary metastases. Six of eight (75%) patients had progressed following two lines of systemic therapy. The objective response rate reached 37.5% (three of eight patients) while stabilized disease was observed in 62.5% (five of eight) of patients. No patient had progressed at initial evaluation. At the last follow up, two patients were still using the combination and three patients had ceased the therapy due to toxicities such as diarrhea, nausea, and emesis. One patient changed to tazemetostat for maintenance and one patient stopped treatment due to coronavirus disease 2019 (COVID-19). Another patient stopped therapy as residual lesions had been radiated. CONCLUSIONS: The combination of irinotecan and Anlotinib as a salvage regimen may be considered another effective treatment option for refractory epithelioid sarcoma. TRIAL REGISTRATION: This study was approved in the Medical Ethics Committee of Peking University People's Hospital on October 28, 2022 (No.: 2022PHD015-002). The study was registered in Clinicaltrials.gov with identifier no. NCT05656222.


Asunto(s)
Benzamidas , Compuestos de Bifenilo , Indoles , Morfolinas , Piridonas , Quinolinas , Sarcoma , Humanos , Irinotecán/uso terapéutico , Vincristina/uso terapéutico , Estudios Retrospectivos , Sarcoma/patología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
13.
Eur Spine J ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418739

RESUMEN

PURPOSE: We have developed a novel technique for osteotomy/discectomy during en bloc resection of spine tumors named two-step osteotomy/discectomy through cannulated screw (TOCS). This study aims at describing the procedure of TOCS technique and assessing its efficiency and safety. METHODS: We retrospectively reviewed fourteen patients who underwent en bloc resection for spine tumors using TOCS technique in our center between August 2018 and September 2022. The technique was based on a specially designed "slotted" cannulated screw which was a cannulated screw with a longitudinal slot to provide the accessibility of T-saw. During osteotomy/discectomy, the "slotted" cannulated screw was inserted obliquely along the plane between the dura and the posterior wall of spine in light of the planned osteotomy/discectomy plane under routine fluoroscopic imaging guidance. The T-saw was introduced through the screw, and the osteotomy/discectomy was performed sequentially in two steps under the guidance of the screw by turning the slot away and toward the dura. The intra-/perioperative complication, neurological function (determined by Frankel grading), surgical margin (determined by a pathologist using AJCC R system), follow-up details were documented. RESULTS: The mean duration of surgery was 599.3 (360-890) min with a mean volume of intra-operative hemorrhage of 2021.4 (800-5000) mL. The intra-/perioperative complications were found in four patients (28.6%). R0 and R1 resections were achieved in nine and five patients, respectively. There was no R2 resection. After a mean follow-up period of 30.6 (10-67) months, all patients were alive except one patient died ten months after surgery due to unrelated cause. No recurrence and implant failure were found. Thirteen patients (92.9%) exhibited completely normal neurological function same as their preoperative neurological status. CONCLUSION: Using TOCS technique can facilitate a precise, complete and safe osteotomy/discectomy procedure during en bloc resection for spine tumor without the aid of intra-operative navigation.

14.
Int J Nanomedicine ; 19: 1145-1161, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38344438

RESUMEN

Introduction: Spatiotemporally controlled release of siRNA for anti-tumor therapy poses significant challenges. Near-infrared (NIR) light, known for its exceptional tissue penetration and minimal tissue invasiveness, holds promise as a viable exogenous stimulus for inducing controlled siRNA release in vivo. However, the majority of light-responsive chemical bonds exhibit absorption wavelengths in the ultraviolet (UV) or short-wavelength visible light range. Methods: To achieve NIR-controlled siRNA release, the study synthesized a UV-sensitive triblock copolymer cRGD-poly(ethylene glycol)-b-poly(aspartic acid ester-5-(2'-(dimethylamino)ethoxy)-2-nitrobenzyl alcohol)-b-polyphenylalanine, abbreviated as cRGD-PEG-PAsp(EDONB)-PPHE. This copolymer is composed of a cRGD-capped PEG block (cRGD-PEG), a poly(aspartate) block modified with cationic moieties through UV-cleavable 2-nitrobenzyl ester bonds [PAsp(EDONB)], and a hydrophobic polyphenylalanine block (PPHE). The cationic amphiphilic polymer cRGD-PEG-PAsp(EDONB)-PPHE can assemble with hydrophobic upconversion nanoparticles (UCNPs) to form a cationic micelle designated as T-UCNP, which subsequently complexes with siRNA to create the final nanopolyplex T-si/UCNP. siRNA-PLK1 was employed to prepare T-PLK1/UCNP nanopolyplex for anti-tumor therapy. Results: T-PLK1/UCNP not only exhibited outstanding tumor cell targeting through cRGD modification but also achieved 980 nm NIR-controlled PLK1 gene silencing. This was achieved by utilizing the encapsulated UCNPs to convert NIR into UV light, facilitating the cleavage of 2-nitrobenzyl ester bonds. As a result, there was a significant suppression of tumor growth. Conclusion: The UCNPs-encapsulated nanopolyplex T-si/UCNP, capable of co-delivering siRNA and UCNPs, enables precise NIR-controlled release of siRNA at the tumor site for cancer RNAi therapy. This nanopolyplex can enhance the controllability and safety of RNAi therapy for tumors, and it also holds the potential to serve as a platform for achieving controlled release and activation of other drugs, such as mRNA and DNA.


Asunto(s)
Nanopartículas , Neoplasias , Animales , ARN Interferente Pequeño/genética , Preparaciones de Acción Retardada/química , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Polímeros , Modelos Animales , Ésteres
15.
Front Surg ; 11: 1336703, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38375409

RESUMEN

Extended reality (XR) technology refers to any situation where real-world objects are enhanced with computer technology, including virtual reality, augmented reality, and mixed reality. Augmented reality and mixed reality technologies have been widely applied in orthopedic clinical practice, including in teaching, preoperative planning, intraoperative navigation, and surgical outcome evaluation. The primary goal of this narrative review is to summarize the effectiveness and superiority of XR-technology-assisted intraoperative navigation in the fields of trauma, joint, spine, and bone tumor surgery, as well as to discuss the current shortcomings in intraoperative navigation applications. We reviewed titles of more than 200 studies obtained from PubMed with the following search terms: extended reality, mixed reality, augmented reality, virtual reality, intraoperative navigation, and orthopedic surgery; of those 200 studies, 69 related papers were selected for abstract review. Finally, the full text of 55 studies was analyzed and reviewed. They were classified into four groups-trauma, joint, spine, and bone tumor surgery-according to their content. Most of studies that we reviewed showed that XR-technology-assisted intraoperative navigation can effectively improve the accuracy of implant placement, such as that of screws and prostheses, reduce postoperative complications caused by inaccurate implantation, facilitate the achievement of tumor-free surgical margins, shorten the surgical duration, reduce radiation exposure for patients and surgeons, minimize further damage caused by the need for visual exposure during surgery, and provide richer and more efficient intraoperative communication, thereby facilitating academic exchange, medical assistance, and the implementation of remote healthcare.

16.
Nat Commun ; 15(1): 513, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38218871

RESUMEN

Among today's nonvolatile memories, ferroelectric-based capacitors, tunnel junctions and field-effect transistors (FET) are already industrially integrated and/or intensively investigated to improve their performances. Concurrently, because of the tremendous development of artificial intelligence and big-data issues, there is an urgent need to realize high-density crossbar arrays, a prerequisite for the future of memories and emerging computing algorithms. Here, a two-terminal ferroelectric fin diode (FFD) in which a ferroelectric capacitor and a fin-like semiconductor channel are combined to share both top and bottom electrodes is designed. Such a device not only shows both digital and analog memory functionalities but is also robust and universal as it works using two very different ferroelectric materials. When compared to all current nonvolatile memories, it cumulatively demonstrates an endurance up to 1010 cycles, an ON/OFF ratio of ~102, a feature size of 30 nm, an operating energy of ~20 fJ and an operation speed of 100 ns. Beyond these superior performances, the simple two-terminal structure and their self-rectifying ratio of ~ 104 permit to consider them as new electronic building blocks for designing passive crossbar arrays which are crucial for the future in-memory computing.

17.
J Org Chem ; 89(2): 1064-1072, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38190807

RESUMEN

α-Functionalization of carbonyl compounds is an important reaction in synthetic chemistry. However, the development of novel synthetic strategies to realize this reaction is challenging. This study describes the α-indolmethylation of carbonyl compounds using cooperative copper, amine, and hydrogen-bond catalysis. This reaction provides a novel and efficient strategy for developing indolmethylated carbonyl compounds by deaminative coupling of gramines.

18.
Int Orthop ; 48(2): 581-601, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37966532

RESUMEN

PURPOSE: There were fewer data to guide the application of enhanced recovery after surgery (ERAS) theory into sacral tumour surgery. In the present study, we were aiming to describe a multidisciplinary program of ERAS and evaluate the availability in sacral tumour surgery. METHODS: This was a prospective study of patients with sacral tumour between March 2021 and September 2021 at a single centre. We proposed a multidisciplinary program of ERAS for pre-admission, preoperative, intraoperative, postoperative, and post-discharge clinical care which positively influenced outcomes of patients with sacral tumour. All patients were prospectively assigned into two groups, ERAS group in which patients received ERAS protocols (n = 63), No-ERAS group in which patients had conventional clinical pathways (n = 62). Patient data were collected which included demographics, preoperative preparation, detailed information of surgical procedure, 60-day reoperation rate, 60-day readmission, postoperative length of stay (PLOS), time to first ambulation and flatus after surgery, time to removal of last drainage tube, and visual analogue scale (VAS) score at first ambulation and discharge. Complications referred to ones that occurred within 60 days after surgery. The above parameters were compared between ERAS group and No-ERAS group. RESULTS: Time to first ambulation after surgery in ERAS group (mean 20.9 h) was significantly shorter than that in No-ERAS group (mean 104.3 ho). Meanwhile, time to first flatus after surgery in ERAS group (mean 26.7 h) was also significantly shorter than that in No-ERAS group (mean 37.3 h). Patients in ERAS group had statistically shorter PLOS (10.7 days) as compared to that in No-ERAS group (13.8 days). In ERAS group, 19 of 63 patients (30.2%) were discharged within seven days after surgery as compared to seven of 62 patients (11.3%) in No-ERAS group. VAS score at first ambulation in ERAS group was not obviously higher than that in No-ERAS group though the time of first ambulation in ERAS group was statistically earlier than one in No-ERAS group. Furthermore, VAS score at discharge in ERAS group was significantly lower than that in No-ERAS group. The rate of postoperative incision necrosis was 6.3% (4/63) in ERAS group and 8.1% (5/62) in No-ERAS group and all of these nine patients underwent reoperation before discharge. The difference was not statistically significant in the wound complication of incision necrosis and 60-day reoperation rate. Only one readmission occurred in No-ERAS group due to the surgical site infection and also there was no significant difference of 60-day readmission rate between these two groups. Furthermore, there was no statistical difference of complications of femoral artery thrombosis and rectal rupture between ERAS group and No-ERAS group. CONCLUSIONS: Our proposed ERAS pathway for sacral tumour surgery and early walking facilitate safe and prompt discharge. ERAS protocols of sacral tumour surgery could decrease PLOS without significantly increasing postoperative complications, 60-day readmission rate and 60-day reoperation rate. The application of ERAS pathway in the field of sacral tumour surgery should have personalized feature with regard to resection type.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Neoplasias , Humanos , Estudios Prospectivos , Cuidados Posteriores , Flatulencia , Alta del Paciente , Hospitales , Necrosis , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos
19.
Org Lett ; 25(50): 9041-9046, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38088909

RESUMEN

An α-diazodifluoroethane sulfonium reagent was developed in this study to undergo [3 + 2] radical cyclization with unactivated alkynes to give the corresponding 3-difluoromethyl pyrazoles under blue light irradiation conditions. The key to the success of this transformation lies in the formation of an electron donor-acceptor (EDA) complex between an electron-deficient α-diazo sulfonium salt and an electron-rich triaryl amine. This study circumvents a major substrate scope limitation in polar cycloaddition reactions of existent diazodifluoroethane reagents.

20.
Exploration (Beijing) ; 3(3): 20220126, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37933380

RESUMEN

Analog storage through synaptic weights using conductance in resistive neuromorphic systems and devices inevitably generates harmful heat dissipation. This thermal issue not only limits the energy efficiency but also hampers the very-large-scale and highly complicated hardware integration as in the human brain. Here we demonstrate that the synaptic weights can be simulated by reconfigurable non-volatile capacitances of a ferroelectric-based memcapacitor with ultralow-power consumption. The as-designed metal/ferroelectric/metal/insulator/semiconductor memcapacitor shows distinct 3-bit capacitance states controlled by the ferroelectric domain dynamics. These robust memcapacitive states exhibit uniform maintenance of more than 104 s and well endurance of 109 cycles. In a wired memcapacitor crossbar network hardware, analog vector-matrix multiplication is successfully implemented to classify 9-pixel images by collecting the sum of displacement currents (I = C × dV/dt) in each column, which intrinsically consumes zero energy in memcapacitors themselves. Our work sheds light on an ultralow-power neural hardware based on ferroelectric memcapacitors.

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