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1.
Chem Sci ; 15(34): 13807-13822, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39211491

ABSTRACT

Electrochemical hydrogen peroxide (H2O2) production via two-electron oxygen reduction reaction (2e- ORR) has received increasing attention as it enables clean, sustainable, and on-site H2O2 production. Mimicking the active site structure of H2O2 production enzymes, such as nickel superoxide dismutase, is the most intuitive way to design efficient 2e- ORR electrocatalysts. However, Ni-based catalysts have thus far shown relatively low 2e- ORR activity. In this work, we present the design of high-performing, atomically dispersed Ni-based catalysts (Ni ADCs) for H2O2 production through understanding the formation chemistry of the Ni-based active sites. The use of a precoordinated precursor and pyrolysis within a confined nanospace were found to be essential for generating active Ni-N x sites in high density and increasing carbon yields, respectively. A series of model catalysts prepared from coordinating solvents having different vapor pressures gave rise to Ni ADCs with controlled ratios of Ni-N x sites and Ni nanoparticles, which revealed that the Ni-N x sites have greater 2e- ORR activity. Another set of Ni ADCs identified the important role of the degree of distortion from the square planar structure in H2O2 electrosynthesis activity. The optimized catalyst exhibited a record H2O2 electrosynthesis mass activity with excellent H2O2 selectivity.

2.
World J Clin Cases ; 12(17): 3177-3182, 2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38898872

ABSTRACT

BACKGROUND: Supernumerary phantom limb (SPL) sensation is the experience of additional limbs, either single or a pair of limbs. Unique to traumatic spinal cord injuries, we report effect of transcranial direct current stimulation (tDCS) on SPL pain in a patient with cervical cord injury. CASE SUMMARY: The subject was a 57-year-old man who was diagnosed with complete spinal cord injury (C6/C5, motor level; C5/C5, sensory level; AIS-A) approximately three months ago. After a period of 2 wk, we administered anodal tDCS over the motor cortex for 15 minutes at an intensity of 1.5 mA. Following that treatment, the patient experienced a decrease of SPL pain intensity and frequency, which lasted for 1 week after the end of treatment. CONCLUSION: Targeting the motor cortex through neuromodulation appears to be a promising option for the management of SPL pain.

3.
Clin Orthop Surg ; 16(3): 347-356, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38827766

ABSTRACT

Artificial intelligence (AI) has rapidly transformed various aspects of life, and the launch of the chatbot "ChatGPT" by OpenAI in November 2022 has garnered significant attention and user appreciation. ChatGPT utilizes natural language processing based on a "generative pre-trained transfer" (GPT) model, specifically the transformer architecture, to generate human-like responses to a wide range of questions and topics. Equipped with approximately 57 billion words and 175 billion parameters from online data, ChatGPT has potential applications in medicine and orthopedics. One of its key strengths is its personalized, easy-to-understand, and adaptive response, which allows it to learn continuously through user interaction. This article discusses how AI, especially ChatGPT, presents numerous opportunities in orthopedics, ranging from preoperative planning and surgical techniques to patient education and medical support. Although ChatGPT's user-friendly responses and adaptive capabilities are laudable, its limitations, including biased responses and ethical concerns, necessitate its cautious and responsible use. Surgeons and healthcare providers should leverage the strengths of the ChatGPT while recognizing its current limitations and verifying critical information through independent research and expert opinions. As AI technology continues to evolve, ChatGPT may become a valuable tool in orthopedic education and patient care, leading to improved outcomes and efficiency in healthcare delivery. The integration of AI into orthopedics offers substantial benefits but requires careful consideration and continuous improvement.


Subject(s)
Artificial Intelligence , Orthopedic Procedures , Humans , Natural Language Processing , Patient Care
4.
Medicina (Kaunas) ; 60(5)2024 May 20.
Article in English | MEDLINE | ID: mdl-38793022

ABSTRACT

Background and Objectives: Endoscopic epidural neuroplasty (EEN) facilitates adhesiolysis through direct epiduroscopic visualization, offering more precise neural decompression than that exhibited by percutaneous epidural neuroplasty (PEN). We aimed to compare the effects of EEN and PEN for 6 months after treatment with lower back and radicular pain in patients. Methods: This retrospective study compared the visual analog scale (VAS) and Oswestry disability index (ODI) scores in patients with low back and radicular pain who underwent EEN or PEN with a steering catheter. The medical records of 107 patients were analyzed, with 73 and 34 undergoing EEN and PEN, respectively. Results: The VAS and ODI scores decreased at all time points after EEN and PEN. VAS and ODI scores decreased more in the EEN group than those in the PEN group at 1 day and 1- and 6-months post-procedure, indicating superior pain relief for both lower back and radicular pain through EEN. Conclusions: EEN is a superior treatment of pain control than PEN in lower back and radicular pain patients.


Subject(s)
Low Back Pain , Humans , Low Back Pain/surgery , Low Back Pain/therapy , Female , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Follow-Up Studies , Aged , Adult , Endoscopy/methods , Pain Measurement/methods , Epidural Space , Decompression, Surgical/methods
5.
Anesth Pain Med (Seoul) ; 19(2): 156-160, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38725171

ABSTRACT

BACKGROUND: Mounier-Kuhn syndrome (MKS) is a rare disorder characterized by abnormal dilation of the trachea and main bronchi. MKS can be easily missed on chest X-rays, making diagnosis difficult. Under general anesthesia, challenges such as airway leakage or collapse during mechanical ventilation may complicate the achievement of adequate tidal volumes. CASES: A 94-year-old woman requiring emergency hemiarthroplasty of the hip under general anesthesia was admitted. Preoperative chest X-rays revealed dilation of the trachea and main bronchi, but the patient exhibited no respiratory symptoms. We diagnosed her with MKS and opted for an 8.0-mm-inner-diameter reinforced tracheal tube. We positioned the cuff in the subglottic area, inflating it while monitoring for air leakage. Throughout the surgery, adequate tidal volume was maintained. CONCLUSIONS: Anesthesiologists must conduct a comprehensive evaluation of patients with MKS, including a review of chest radiographs, and establish a meticulous anesthesia plan prior to surgery.

6.
J Craniofac Surg ; 35(4): e354-e357, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38587387

ABSTRACT

Scalp reconstruction has always been a challenging problem for even the most experienced surgeon to provide good aesthetic and functional results. This is mainly because the scalp is less mobile and tight, requiring a much larger dissection for the size of the original defect. We hypothesized that the omega variant perforator-based keystone island flap at the subgaleal plane provides a versatile and easily reproducible reconstructive option for scalp reconstruction after wide skin cancer excision. We reviewed all patients who underwent reconstruction with the keystone flap or its modification to repair scalp defects following wide resection of skin cancer in the scalp abutting calvarium from May 2021 to July 2023. We designed the flap width 50% wider than original keystone flap design first introduced by Dr. Behan. We reconstructed medium- to large-sized scalp defects ranging from 2×2 to 5×5 cm 2 using an omega variant perforator-based keystone island flap. All patients were satisfied with the aesthetic outcomes without complications. Keystone flaps are a versatile option for reconstructing the scalp after cancer resection. This strategy obviates the need for skin grafting, myocutaneous flap or free flap after cancer removal in the scalp.


Subject(s)
Carcinoma, Basal Cell , Perforator Flap , Plastic Surgery Procedures , Scalp , Skin Neoplasms , Humans , Scalp/surgery , Skin Neoplasms/surgery , Skin Neoplasms/pathology , Male , Female , Carcinoma, Basal Cell/surgery , Aged , Middle Aged , Plastic Surgery Procedures/methods , Skull/surgery , Aged, 80 and over , Neoplasm Invasiveness , Head and Neck Neoplasms/surgery , Adult
7.
Clin Orthop Surg ; 16(2): 303-312, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38562639

ABSTRACT

Background: Glenoid position and inclination are important factors in protecting against scapular notching, which is the most common complication that directly affects the longevity of reverse shoulder arthroplasty (RSA). This study aimed to investigate the biomechanical characteristics of glenosphere orientation, comparing neutral tilt, inferior overhang with an eccentric glenosphere at the same placement of baseplate, and inferior tilt after 10° inferior reaming in the lower part of the glenoid in RSA. Methods: Nine cadaveric shoulders were tested with 5 combinations of customized glenoid components: a centric glenosphere was combined with a standard baseplate (group A); an eccentric glenosphere to provide 4-mm inferior overhang than the centric glenosphere was combined with a standard baseplate (group B); a centric glenosphere was combined with a wedge-shaped baseplate tilted inferiorly by 10° with the same center of rotation (group C); an eccentric glenosphere was attached to a wedge-shaped baseplate (group D); and 10° inferior reaming was performed on the lower part of the glenoid to apply 10° inferior tilt, with a centric glenosphere secured to the standard baseplate for simulation of clinical tilt (group E). Impingement-free angles for adduction, abduction, forward flexion, external rotation, and internal rotation were measured. The capability of the deltoid moment arm for abduction and forward flexion, deltoid length, and geometric analysis for adduction engagement were evaluated. Results: Compared with neutral tilt, inferior tilt at the same position showed no significant difference in impingement-free angle, moment arm capability, and deltoid length. However, group D resulted in better biomechanical properties than a central position, regardless of inferior tilt. Group E demonstrated a greater range of adduction, internal and external rotation, and higher abduction and forward flexion capability with distalization, compared to corresponding parameters for inferior tilt with a customized wedge-shaped baseplate. Conclusions: A 10° inferior tilt of the glenosphere, without changing the position of the baseplate, had no benefit in terms of the impingement-free angle and deltoid moment arm. However, an eccentric glenosphere had a significant advantage, regardless of inferior tilt. Inferior tilt through 10° inferior reaming showed better biomechanical results than neutral tilt due to the distalization effect.


Subject(s)
Arthroplasty, Replacement, Shoulder , Shoulder Joint , Shoulder Prosthesis , Humans , Arthroplasty, Replacement, Shoulder/methods , Shoulder Joint/surgery , Shoulder/surgery , Scapula , Range of Motion, Articular , Biomechanical Phenomena
8.
Bioengineering (Basel) ; 11(4)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38671801

ABSTRACT

XRD diffraction and IR absorption were investigated for raw loess powder and heat-treated loess powder. Raw loess retains its useful minerals, but loses their beneficial properties when calcined at 850 °C and 1050 °C. To utilize the useful minerals, loess balls were made using a low-temperature wet-drying method. The radiant energy and transmittance were measured for the loess balls. Far-infrared ray (FIR) emitted from loess bio-balls is selectively absorbed as higher vibrational energy by water molecules. FIR can raise the body's core temperature, thereby improving blood flow through the body's thermoregulatory mechanism. In an exploratory study with 40 participants, when the set temperature of the loess ball mat was increased from 25 °C to 50 °C, blood flow increased by 39.01%, from 37.48 mL/min to 52.11 mL/min, in the left middle finger; in addition, it increased by 39.62%, from 37.15 mL/min to 51.87 mL/min, in the right middle finger. The FIR emitted from loess balls can be widely applied, in various forms, to diseases related to blood flow, such as cold hands and feet, diabetic foot, muscle pain, and menstrual pain.

9.
Antioxidants (Basel) ; 13(1)2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38247510

ABSTRACT

Tendinopathy is a debilitating condition marked by degenerative changes in the tendons. Its complex pathophysiology involves intrinsic, extrinsic, and physiological factors. While its intrinsic and extrinsic factors have been extensively studied, the role of physiological factors, such as hypoxia and oxidative stress, remains largely unexplored. This review article delves into the contribution of hypoxia-associated genes and oxidative-stress-related factors to tendon degeneration, offering insights into potential therapeutic strategies. The unique aspect of this study lies in its pathway-based evidence, which sheds light on how these factors can be targeted to enhance overall tendon health.

10.
J Shoulder Elbow Surg ; 33(3): 678-685, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37572747

ABSTRACT

BACKGROUND: This study compared the clinical outcomes of open subpectoral biceps tenodesis and arthroscopic suprapectoral biceps tenodesis for symptomatic biceps tenosynovitis. Although both techniques have pros and cons, no studies have compared clinical and functional outcomes during the recovery phase. Previous studies show that suprapectoral tenodesis has a higher probability of Popeye deformity and postoperative bicipital pain and stiffness, whereas subpectoral tenodesis has a higher risk of nerve complications and wound infections. This study aimed for clinical comparison between arthroscopic suprapectoral biceps tenodesis and open subpectoral biceps tenodesis. METHODS: This study is a retrospective review of institutional records of patients with biceps tendinitis who underwent open or arthroscopic biceps tenodesis. Surgical indications included biceps tenosynovitis, biceps partial tear, and biceps pulley lesion. Patients with prior shoulder surgery, preoperative shoulder stiffness, or full-thickness tear of rotator cuff were excluded. Tenodesis was considered when the pain recurs within 3 months despite conservative treatment including at least 2 triamcinolone injections on the biceps tendon sheath. Visual analog scale (VAS) score for pain, presence of the night pain, American Shoulder and Elbow Surgeons (ASES) score, Constant score, and range of motion were assessed preoperatively at 3, 6, 12, and 24 months postoperatively and the last follow-up. RESULTS: A total of 72 patients (33 with arthroscopic suprapectoral biceps tenodeses and 39 with open subpectoral biceps tenodeses) were included in analysis. At postoperative 6 months, lower VAS score (0.4 ± 0.8 vs. 1.7 ± 1.9, P < .001), and the presence of the night pain (2 [6%] vs. 14 [36%], P = .002), ASES score (89.6 ± 9.2 vs. 81.4 ± 14.6, P = .006), and Constant score (89.4 ± 5.6 vs. 82.0 ± 12.5, P = .003) compared with the subpectoral group. The mean number of postoperative steroid injections for pain control in the subpectoral group (0.51 ± 0.80) was significantly higher than that in the suprapectoral group (0.18 ± 0.40) (P = .031). However, postoperative clinical outcomes were restored similar between the 2 groups at 12 months and the last follow-up. DISCUSSION: Arthroscopic suprapectoral biceps tenodesis performed statistically better than the subpectoral biceps tenodesis for the VAS, ASES, night pain, and Constant score at postoperative 6 months. However, only night pain and the Constant score showed differences that exceeded minimum clinically important difference during the recovery phase. At postoperative 12 and 24 months, biceps tenodesis provided satisfactory clinical outcomes and pain relief regardless of the fixation technique and suture anchor location.


Subject(s)
Tenodesis , Tenosynovitis , Humans , Tenodesis/methods , Shoulder/surgery , Tenosynovitis/surgery , Arthroscopy/methods , Pain
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