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1.
Chembiochem ; 24(14): e202200572, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37253903

RESUMEN

Controlling PCR fidelity is an important issue for molecular biology and high-fidelity PCR is essential for gene cloning. In general, fidelity control is achieved by protein engineering of polymerases. In contrast, only a few studies have reported controlling fidelity using chemically modified nucleotide substrates. In this report, we synthesized nucleotide substrates possessing a modification on Pγ and evaluated the effect of this modification on PCR fidelity. One of the substrates, nucleotide tetraphosphate, caused a modest decrease in Taq DNA polymerase activity and the effect on PCR fidelity was dependent on the type of mutation. The use of deoxyadenosine tetraphosphate enhanced the A : T→G : C mutation dramatically, which is common when using Taq polymerase. Conversely, deoxyguanosine tetraphosphate (dG4P) suppressed this mutation but increased the G : C→A : T mutation during PCR. Using an excess amount of dG4P suppressed both mutations successfully and total fidelity was improved.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Fosfatos , Polimerasa Taq/genética , Polimerasa Taq/metabolismo , Reacción en Cadena de la Polimerasa , Mutación , Nucleótidos
2.
Haemophilia ; 29(5): 1359-1365, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37639381

RESUMEN

INTRODUCTION: Joint health is one of the most important factors contributing to a healthy life in patients with haemophilia. Recent study revealed that starting early prophylaxis was not enough to prevent joint disease in most paediatric patients with haemophilia. AIM: In this study, we aimed to determine the age-specific incidence of acute joint disease during childhood at single haemophilia treatment centre (HTC). METHOD: The joint health in 48 patients was evaluated based on consecutive US testing for 5 years at annual multidisciplinary comprehensive care. RESULTS: During the study period, 23 patients (47.9%) had no joint disease since the initial examination, whereas 13 patients (27.0%) showed development from negative to positive findings. The incidence of joint disease increased with age: 0% in preschool, 5.3% in elementary school, 14.3% in junior high school and 35% beyond high school age. Among the 13 patients who developed joint disease, two experienced acquired synovitis that resolved during the follow-up period. Statistical analysis revealed that the patients who routinely underwent follow-up by the HTC exhibited a significantly lower incidence of joint disease than did those followed up at other institutions (p < .001). CONCLUSION: These results indicated that close check-up, including routine joint examination using US as well as frequent assessment of pharmacokinetic profile at the HTC, might play an important role in avoiding joint disease among paediatric patients with haemophilia.


Asunto(s)
Hemofilia A , Artropatías , Sinovitis , Humanos , Niño , Preescolar , Hemofilia A/complicaciones , Hemofilia A/epidemiología , Incidencia , Artropatías/complicaciones , Artropatías/epidemiología , Factores de Edad
3.
BMC Musculoskelet Disord ; 24(1): 272, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37038148

RESUMEN

BACKGROUND: In the dynamic condition, knee osteoarthritis (OA) usually presents with pain. In the weight-bearing condition, a medial meniscus extrusion (MME) may cause severe symptoms and pathological progression. However, the correlation between a dynamic MME and pain has not been elucidated. Now, an MME can be evaluated under dynamic conditions and reflect the characteristics of symptomatic knee OA. This study investigated MMEs during walking and their correlation with knee pain. METHODS: Thirty-two symptomatic patients with knee OA (mean age, 60.5 ± 9.9 years) were enrolled in this study. The medial meniscus was evaluated using ultrasonograms during walking, and in the static supine and unipedal standing positions, as dynamic and static conditions, respectively. The ΔMME (the difference between the maximum and minimum MMEs) was obtained in each condition. The intensity of the knee pain during walking was measured by the visual analog scale (VAS). RESULTS: The ΔMME in the dynamic condition was significantly higher than that in the static condition (P < 0.01). There was a significant correlation between VAS and ΔMME only in the dynamic condition. CONCLUSIONS: The dynamic evaluation is a valid tool for understanding the mechanisms of knee pain and the behavior of the medial meniscus in symptomatic knee OA.


Asunto(s)
Articulación de la Rodilla , Meniscos Tibiales , Osteoartritis de la Rodilla , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/patología , Imagen por Resonancia Magnética , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/patología , Articulación de la Rodilla/diagnóstico por imagen , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano
4.
J Infect Chemother ; 28(8): 1208-1211, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35570112

RESUMEN

A 53-year-old male Japanese patient with COVID-19 was admitted to our hospital after his respiratory condition worsened on day 9 of the disease. With the diagnosis of severe COVID-19, treatment with remdesivir, dexamethasone, and unfractionated heparin was started for the prevention of thrombosis. Although the patient's respiratory status data improved after treatment, severe respiratory failure persisted. Thrombocytopenia and D-dimer elevation were observed on day 8 after heparin therapy initiation. Heparin-induced thrombocytopenia (HIT) antibody measured by immunological assay was positive, and contrast computed tomography showed pulmonary artery thrombus. The patient was diagnosed with HIT because the pre-test probability score (4Ts score) for HIT was 7 points. Heparin was changed to apixaban, a direct oral anticoagulant, which resulted in a reduction of the pulmonary thrombus and improvement of the respiratory failure. In patients with COVID-19, anticoagulant therapy with heparin requires careful monitoring of thrombocytopenia and elevated D-dimer as possible complications related to HIT. (151/250 words).


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Embolia Pulmonar , Insuficiencia Respiratoria , Trombocitopenia , Trombosis , Anticoagulantes/efectos adversos , Heparina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/tratamiento farmacológico , Insuficiencia Respiratoria/inducido químicamente , Trombocitopenia/inducido químicamente , Trombocitopenia/diagnóstico , Trombocitopenia/tratamiento farmacológico , Trombosis/tratamiento farmacológico
5.
J Orthop Sci ; 27(6): 1252-1256, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34404614

RESUMEN

BACKGROUND: As a first-line surgical treatment for treating metacarpophalangeal (MCP) joint extension contractures, mobilization surgery with open dorsal approach has been indicated. However, this procedure has the possibility to result in postoperative recurrence over the course of time because its invasive open dorsal approach has a negative impact on the postoperative gliding of the extensor mechanism. We report the preliminarily outcomes of patients who underwent a minimally invasive arthroscopic mobilization to alter and enhance their existing surgical strategy in place of MCP joint extension contractures. METHODS: This retrospective study included seven patients with 13 MCP joint extension contractures who had received an arthroscopic release of the bilateral collateral ligament and/or dorsal capsule of affected MCP joint. The extension contractures were caused by long-time immobilization with inadequate extended position of the MCP joint after either hand and wrist fractures, extensor tendon injury, or peripheral nerve palsy. All patients received sufficient exercise under the supervision of a physical therapist for more than 3 months before surgery. However, physical therapy did not improve the MCP joint extension contractures. We measured the active and passive flexion angles preoperatively at 1 and 6 months after surgery. The passive flexion angle was also measured after arthroscopic mobilization on the operation table. Surgery-related complications regarding nerve, vessel, skin, and tendon were also assessed. RESULTS: In all patients, significant improvements were observed in both the active and passive flexion angles 1 month after surgery, and continued to improve 6 months after surgery. Two out of 13 metacarpophalangeal joints developed blisters on the dorsal side of the joint, but conservatively recovered. CONCLUSIONS: Based on the positive improvements observed in our patients, we conclude that this minimally invasive arthroscopic technique has the potential to alter and enhance the surgical treatment strategy for MCP joint extension contractures.


Asunto(s)
Ligamentos Colaterales , Contractura , Humanos , Estudios Retrospectivos , Contractura/etiología , Contractura/cirugía , Articulación Metacarpofalángica/cirugía , Articulación Metacarpofalángica/fisiología , Rango del Movimiento Articular/fisiología
6.
J Orthop Sci ; 26(6): 1014-1017, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33341354

RESUMEN

BACKGROUND: Vascular disorders in throwing athletes can occur from the thoracic outlet to the fingertips. The occurrence of these disorders around the shoulder is well known, and treatment options have been established for them. However, the occurrence of vascular pathology in the digital arteries in elite baseball pitchers is unclear, and treatment options have not yet been established. We hypothesized that asymptomatic professional baseball pitchers often have existing pathological changes in their digital blood flow; therefore, we quantitatively measured the blood flow in the index finger using ultrasonography and compared the results to those of non-baseball players. METHODS: Seven asymptomatic professional baseball pitchers (pitcher group) and 11 healthy volunteers (control group) were included. The flow velocity, flow volume and vessel resistance index of the ulnar digital artery of the index finger were measured just distal to the proximal interphalangeal joint using pulsed wave Doppler in two positions: 1) with the proximal interphalangeal (PIP) joint relaxed (10-15° flexed) and 2) with the PIP joint passively extended (0-5°). RESULTS: The mean flow velocity and flow volume were lower in the extended position than in the relaxed position in both groups. In the dominant hand, which was the throwing hand in the pitcher group, the mean flow velocity and the flow volume in the relaxed position were significantly lower in the pitcher group than in the control group. The vessel resistance index in the relaxed position of the dominant hand was significantly higher in the pitcher group than in the control group. In the nondominant hand, there was no significant difference in any parameter between the two groups. CONCLUSIONS: Asymptomatic professional baseball pitchers may have a pathological change in digital blood flow in the throwing hand. As treatment options for this condition have not yet been established, it is of utmost importance to carry out periodic examination and prevention before the condition progresses to the symptomatic end stage.


Asunto(s)
Béisbol , Articulación del Hombro , Mano , Humanos , Rango del Movimiento Articular , Hombro , Ultrasonografía
7.
Rapid Commun Mass Spectrom ; 34(8): e8703, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31840282

RESUMEN

RATIONALE: The key to successful experiments in matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is to apply the matrix uniformly to the sample. With the development of automated equipment, uniform matrix application has made great progress while the sample preparation required to acquire a better image becomes complicated. METHODS: The approach is to apply the matrix uniformly to tape and adhere it to the tissue section. We call this the sheet-enhanced technique (Set) method. RESULTS: The Set method promotes ionization of biomolecules as well as the spray method. This procedure does not require the preparation and application of a matrix solution for each experiment, dramatically reducing the time and effort of matrix deposition. CONCLUSIONS: In the present study, we have developed the Set method as a new matrix application method. The method promotes ionization of biomolecules as well as the spray method for MALDI-IMS.

8.
J Ultrasound Med ; 39(6): 1213-1222, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31880342

RESUMEN

OBJECTIVES: To report the clinical utility of high-resolution ultrasound (US) for monitoring vascular compromise after free tissue transfer. METHODS: Fifty-two tissue transfers in the extremities were included in this study. Blood flow around the anastomotic pedicle and subcutaneous tissue of the grafted flap was monitored with pulsed color and power Doppler US whenever the conventional monitoring method, comprising the bedside assessment of the temperature, capillary refill, and flap color, showed abnormalities until 1 week after reconstruction. RESULTS: All flaps were indicated for US monitoring, with 44 flaps showing Doppler signals in each position, even though conventional flap monitoring showed an abnormality. Forty of the 44 flaps showed no flap failure, whereas the remaining 4 flaps developed partial necrosis. Abnormal US findings were noted in 8 of the 52 flaps. Ultrasound revealed interruption of venous blood flow around the anastomotic pedicle in 6 of 8 flaps. Emergent exploration revealed venous occlusion at the anastomotic pedicle, similar to the US finding. In 2 of the 8 flaps, US showed no blood flow to either the anastomotic pedicle or subcutaneous tissue. Emergent exploration revealed arterial occlusion at the anastomotic pedicle. Seven of the 8 reexplored flaps were salvaged after revision surgery with complete flap survival. Partial flap survival was noted in 1 case, but complete flap failure was avoided. CONCLUSIONS: Ultrasound is a useful adjunct that enables a direct assessment of perfusion in grafted tissues, which may reduce unnecessary exploration when conventional flap monitoring shows an abnormality.


Asunto(s)
Extremidades/irrigación sanguínea , Extremidades/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Colgajos Quirúrgicos/irrigación sanguínea , Ultrasonografía/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Procedimientos de Cirugía Plástica/métodos
9.
J Orthop Sci ; 23(6): 959-966, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30100212

RESUMEN

BACKGROUND: Dynamic external fixation is a useful treatment option for unstable fracture-dislocations of the proximal interphalangeal (PIP) joint, because it simultaneously reduces axial pressure load on the joint surface, maintains congruent joint reduction, and permits early joint motion. However, most current devices are large, hindering finger movement, and unstable. To address these problems, we developed a dynamic external finger fixator, named the Micro Ortho Fixator®. The purpose of this study was to review the results of using the new external finger fixator to treat unstable fracture-dislocations of the PIP joint. MATERIALS AND METHODS: Nine patients who sustained unstable fracture-dislocation injuries of the PIP joint were treated with the Micro Ortho Fixator®. Seven fractures were accompanied by depressed bony fragments at the base of the middle phalanx. All patients were evaluated for pain and range of PIP motion at the final follow-up. Radiographs of the affected fingers were evaluated for PIP congruity and reduction. The mean follow-up duration was 11.1 months (range: 6-33 months). RESULTS: At the final follow-up, pain averaged 0.3 (range: 0-2) on the Numeric Pain Rating Scale, and the total arc of motion at the PIP joint averaged 91.2° (range: 50-110°). All fractures had healed, and the intra-articular step-off improved from 1.9 mm (SD: 1.0) before surgery to 0.2 mm (SD: 0.4) at the final follow-up. The patients who sustained sports injuries returned to competition after an average of 3.5 months (range: 2.5-4 months). CONCLUSION: The external fixator is compact and facilitates range-of-motion (ROM) exercises, has high stability, and achieves good joint congruity and an ROM equivalent to the healthy joint of the patient. STUDY DESIGN/LEVEL OF EVIDENCE: Therapeutic/IV.


Asunto(s)
Ambulación Precoz/instrumentación , Fijadores Externos , Articulaciones de los Dedos , Fractura-Luxación/cirugía , Osteogénesis por Distracción/instrumentación , Adolescente , Adulto , Femenino , Humanos , Masculino , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
10.
J Clin Ultrasound ; 46(4): 247-252, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29210084

RESUMEN

PURPOSE: To compare the diagnostic accuracies of ultrasonography (US) and magnetic resonance imaging (MRI) with intraoperative capitellar osteochondritis dissecans (COCD) fragment stability findings. METHODS: Patients whose International Cartilage Repair Society (ICRS) osteochondritis dissecans (OCD) classifications were I/II (stable) or III (unstable) were included. Patients underwent preoperative US and MRI. On US, lesions were evaluated as unstable when irregular contours of the chondral surface were observed. On MRI, lesions were evaluated as unstable when articular bone irregularity, a T2 high signal intensity interface, or a high signal intensity line through the articular cartilage was observed. Using the surgical assessment as the gold standard, accuracies of fragment stability diagnoses were calculated for US and MRI. RESULTS: Thirty-four patients with OCD classifications of I/II (stable) or III (unstable) were included. Twenty-four patients (stable: 12, unstable: 12) underwent preoperative US; 22 (stable: 11, unstable: 11) underwent preoperative MRI. Preoperative US and MRI stability assessments correctly matched intraoperative fragment findings in 23 of 24 patients and 16 of 22 patients, respectively. US criteria in this study achieved superior accuracy compared with MRI criteria (96% vs. 73%; P < .05). CONCLUSION: US was a useful tool for evaluating fragment instability in COCD.


Asunto(s)
Articulación del Codo/diagnóstico por imagen , Inestabilidad de la Articulación/diagnóstico por imagen , Imagen por Resonancia Magnética , Osteocondritis Disecante/diagnóstico por imagen , Cuidados Preoperatorios/métodos , Adolescente , Niño , Articulación del Codo/cirugía , Humanos , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/cirugía , Masculino , Osteocondritis Disecante/complicaciones , Osteocondritis Disecante/cirugía , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía
11.
Muscle Nerve ; 55(4): 508-512, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27490844

RESUMEN

INTRODUCTION: In recent operative cases of anterior interosseous nerve palsy (AINP), hourglass-like fascicular constrictions have been reported. We prospectively investigated the ultrasonographic history of these lesions to better understand the role of this lesion in AINP. METHODS: Seven patients who were diagnosed with idiopathic AINP based on classic clinical findings and had hourglass-like fascicular constrictions found on ultrasonography were included. All but 1 patient selected surgery, and we followed up all patients clinically and with ultrasonography. RESULTS: In the 5 patients treated surgically in whom paralysis recovered to a level greater than M4, postoperative ultrasonography revealed less constriction. The other patient experienced little recovery after surgery, and the severe constriction remained. In a conservatively treated patient, the paralysis recovered completely, and upon ultrasonography, the constriction had lessened. CONCLUSIONS: Although the mechanism is still unknown, hourglass-like fascicular constriction lessened with relief of motor weakness both in operatively and conservatively treated patients. Muscle Nerve 55: 508-512, 2017.


Asunto(s)
Constricción Patológica , Neuropatías Cubitales , Adulto , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/fisiopatología , Constricción Patológica/cirugía , Femenino , Antebrazo/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/métodos , Recuperación de la Función/fisiología , Neuropatías Cubitales/diagnóstico por imagen , Neuropatías Cubitales/fisiopatología , Neuropatías Cubitales/cirugía , Adulto Joven
12.
Acta Radiol ; 58(10): 1231-1237, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28090794

RESUMEN

Background Hemangiomas are sometimes difficult to diagnose with current techniques. Sluggish speed signs (SSS) are a phenomenon that: (i) cannot be depicted as Doppler flow on Doppler ultrasound; (ii) can be observed as fluid movements on Doppler ultrasound; and (iii) cannot be depicted as waveforms on pulse Doppler mode. We hypothesized that SSS could be diagnostic indicators for hemangiomas. Purpose To evaluate whether ultrasound findings, in particular those relating to SSS, are a reliable tool for detecting hemangiomas compared to magnetic resonance imaging (MRI) and the gold standard for hemangioma diagnosis: pathological examination by biopsy or after surgical resection. Material and Methods Totally, 105 patients (mean age, 44.9 years) with soft-tissue tumors underwent MRI and ultrasound examination before biopsy or tumor resection. Ultrasound findings were compared with MRI as well as pathological findings, which were used as reference. Results Hemangiomas were identified in 16 (6.25%) of the 105 patients. On MRI, flow voids showed sensitivity and specificity values of 81.3% and 96.6%, respectively. On ultrasound examination, SSS was the only finding to show equally high sensitivity (93.8%) and specificity (96.6%) for diagnosing hemangiomas. There was no significant difference in the diagnostic capabilities between these two parameters ( P = 0.479). Conclusion SSS showed a high sensitivity and specificity for diagnosing hemangiomas and therefore are useful diagnostic tools to supplement MRI.


Asunto(s)
Hemangioma/diagnóstico por imagen , Hemangioma/fisiopatología , Imagen por Resonancia Magnética , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/fisiopatología , Ultrasonografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía Doppler en Color , Adulto Joven
14.
Gait Posture ; 110: 23-28, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38471424

RESUMEN

BACKGROUND: In patients with medial knee osteoarthritis (OA), medial meniscus extrusion during gait is aggravated by mechanical stress, such as knee adduction moment (KAM). Conversely, the decrease in the range of knee rotation during stance phase is also one of the important issues in early knee OA, whereas the correlation between medial meniscus extrusion and knee rotation during gait are unclear. RESEARCH QUESTION: To investigate the correlation between increase in medial meniscus extrusion and range of knee rotation during gait in patients with early- and late-stage of knee OA. METHODS: Forty patients with medial knee OA were enrolled and divided into early- and late-OA group by Kellgren-Lawrence grading scale. During gait tasks, the extent of medial meniscus extrusion was measured using ultrasonography and kinetic/kinematic data were measured using three-dimensional motion analysis system. The correlation between medial meniscus extrusion and the range of knee rotation or KAM were evaluated in the overall, early-, and late- OA groups. RESULTS: A significant negative correlation was observed between an increase in medial meniscus extrusion and range of knee rotation angle in early-OA group only. However, an increase in medial meniscus extrusion significantly correlated with the second KAM peak in the overall and early-OA groups. SIGNIFICANCE: The decrease in range of knee rotation during stance phase may be associated with the increase in medial meniscus extrusion during gait in patients with early knee OA.


Asunto(s)
Marcha , Meniscos Tibiales , Osteoartritis de la Rodilla , Rango del Movimiento Articular , Humanos , Osteoartritis de la Rodilla/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Marcha/fisiología , Meniscos Tibiales/fisiopatología , Meniscos Tibiales/diagnóstico por imagen , Anciano , Rango del Movimiento Articular/fisiología , Fenómenos Biomecánicos , Rotación , Ultrasonografía , Articulación de la Rodilla/fisiopatología
15.
Front Sports Act Living ; 6: 1271987, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650839

RESUMEN

Purpose: Excessive mechanical stress accumulates and causes knee injury. Meniscal extrusion is a key factor in detecting the reaction to cumulative mechanical stress. The accumulation of stress strongly depends on environmental conditions such as flat ground or uphill/downhill, and accumulates in knee compartments; only a few studies have reported the effects of different environments on lateral and medial meniscus extrusion. This study aimed to investigate the effects of cumulative uphill/downhill stress on the meniscal extrusion in each compartment. Methods: A total of 30 healthy volunteers with 30 affected knees were involved in this cohort study (mean age, 22.0 ± 1.1 years; men, n = 14). The participants were divided into flat-walking, uphill/downhill-walking, and uphill/downhill-jogging groups and their numbers of steps taken were recorded during the effort. Moreover, medial and lateral meniscal extrusions during walking were evaluated using ultrasound three times, before and after efforts (T1) and (T2), and one day after efforts (T3), respectively. Results: In the flat-walking group, no significant differences were observed between the follow-up periods. Conversely, in the uphill/downhill-walking and jogging groups, the medial meniscus extrusion at T2 was significantly higher than that at T1. Conversely, the medial meniscus extrusion at T3 was significantly lower than that at T2. By contrast, the lateral meniscus did not show any difference between the follow-up periods in any group. Conclusion: Temporary extrusion of the meniscus occurred after uphill/downhill tasks in healthy volunteers, and its reaction was observed only in the medial meniscus.

16.
J Am Chem Soc ; 135(38): 14172-8, 2013 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-24015779

RESUMEN

Oligonucleotide-templated reactions are powerful tools for the detection of nucleic acid sequences. One of the major scientific challenges associated with this technique is the rational design of non-enzyme-mediated catalytic templated reactions capable of multiple turnovers that provide high levels of signal amplification. Herein, we report the development of a nucleophilic aromatic substitution reaction-triggered fluorescent probe. The probe underwent a rapid templated reaction without any of the undesired background reactions. The fluorogenic reaction conducted in the presence of a template provided a 223-fold increase in fluorescence after 30 s compared with the nontemplated reaction. The probe provided an efficient level of signal amplification that ultimately enabled particularly sensitive levels of detection. Assuming a simple model for the templated reactions, it was possible to estimate the rate constants of the chemical reaction in the presence and in the absence of the template. From these kinetic analyses, it was possible to confirm that an efficient turnover cycle had been achieved, on the basis of the dramatic enhancement in the rate of the chemical reaction considered to be the rate-determining step. With maximized turnover efficiency, it was demonstrated that the probe could offer a high turnover number of 1500 times to enable sensitive levels of detection with a detection limit of 0.5 pM in the catalytic templated reactions.


Asunto(s)
ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Aminocumarinas/química , Secuencia de Bases , Benzoatos/química , Colorantes Fluorescentes/química , Cinética , Límite de Detección , Oligonucleótidos/química , Compuestos de Sulfhidrilo/química
17.
Hand Surg Rehabil ; 42(5): 424-429, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37353200

RESUMEN

OBJECTIVES: The effect of metacarpophalangeal joint position and finger joint movement speed on lumbrical muscle activity remains unproven and was examined in this study. MATERIAL AND METHODS: Twenty-four healthy adults performed flexion-extension movements of the index finger in different metacarpophalangeal joint positions (extension or flexion) and movement speeds (60, 120, 240, and 360 beats per minute). The activities of the first lumbrical, first dorsal interosseous, and extensor digitorum muscles were evaluated using surface electromyography, and compared with those during finger joint extension. RESULTS: The metacarpophalangeal joint positions affected only lumbrical muscle activity, which was greater during extension. Further, finger movement speed affected the lumbrical and extensor digitorum muscle activities, which increased with increasing movement speeds. CONCLUSION: The present study suggests that position and movement speed can influence the lumbrical muscle activity during metacarpophalangeal joint extension. These findings may help expound lumbrical function and develop suitable strategies for inducing lumbrical muscle activity.


Asunto(s)
Articulaciones de los Dedos , Músculo Esquelético , Adulto , Humanos , Articulaciones de los Dedos/fisiología , Músculo Esquelético/fisiología , Dedos/fisiología , Mano , Articulación Metacarpofalángica/fisiología
18.
J Biomech ; 158: 111748, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37633216

RESUMEN

Although placing surface electrodes on small muscles by palpation is difficult, ultrasound guidance may enable electrode placement on the small muscles. This study aimed to examine whether ultrasound guidance is helpful for placement of electrodes on a small muscle, such as the hand lumbrical muscle. Twelve dominant hands of 12 healthy right-handed adults were included in this study. The first lumbrical muscle belly of the hands was identified using ultrasound guidance with a string navigation technique for placing surface electrodes. This technique was designed to identify the location of the center of the muscle belly under ultrasound imaging using a string. After the electrodes were placed on the muscle belly using this technique, the surface electromyographic signals of the first lumbrical, first dorsal interosseous, and adductor pollicis muscles were recorded. The activity of the lumbrical muscle could be separately measured of the first dorsal interosseous and adductor pollicis muscles. This technique has the potential to enable surface electromyography of small muscles for which placement of surface electrodes by palpation is challenging.


Asunto(s)
Mano , Músculo Esquelético , Electromiografía/métodos , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiología , Mano/diagnóstico por imagen , Mano/fisiología , Pulgar , Ultrasonografía
19.
Artículo en Inglés | MEDLINE | ID: mdl-37701530

RESUMEN

Background: This study aimed to investigate the effect of high tibial osteotomy (HTO) on medial meniscus extrusion (MME) and the association between the changes in limb alignment and MME under weight-bearing (WB) conditions after HTO. Methods: We included 17 patients with knee osteoarthritis (OA) who underwent HTO. MME was evaluated using ultrasonography in supine and unipedal standing positions. Knee alignment was evaluated radiographically using WB, whole-leg radiographs with the hip-knee-ankle angle (HKAA), percentage of the mechanical axis (%MA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA). All measurements were performed serially at four time points: preoperative and 3, 6, and 12 months postoperative. Clinical outcomes were assessed by knee injury and osteoarthrosis outcome score (KOOS) and visual analogue scale (VAS) value for pain. Results: Mean MME in the WB position was significantly greater than that in the supine position in the preoperative condition; however, MME in both supine and WB positions was significantly lowered postoperatively. The ΔMME, difference of MME between supine and WB positions, was significantly lowered postoperatively and maintained for up to 1 year. MME change in the WB position between preop and postoperative conditions was significantly correlated with change in HKAA and %MA at 1 year postoperative. KOOS and VAS score were significantly improved after HTO. Conclusions: HTO correcting varus alignment can decrease MME in WB position and minimise the change in MME between supine and WB positions. The changes in MME after HTO were correlated with changes in the mechanical alignments.

20.
J Med Ultrason (2001) ; 50(2): 229-236, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36800121

RESUMEN

PURPOSE: The cumulative knee adduction moment (KAM) is a key parameter evaluated for the prevention of overload knee injuries on the medial compartment. Medial meniscus extrusion (MME), typical in hoop dysfunctions, is a measure for the cumulative mechanical stress in individual knees; however, its correlation with cumulative KAM is unknown. The aim of this study was to investigate the effect of temporary overload stress on MME and its correlation with cumulative KAM. METHODS: Thirteen healthy asymptomatic volunteers (13 knees) were recruited for a cohort study (mean age, 23.1 ± 3.3 years; males: n = 8). The cumulative KAM was calculated using a three-dimensional motion analysis system, in addition to the number of steps taken while jogging uphill or downhill. MME was evaluated using ultrasound performed in the standing position. The evaluations were performed four times: at baseline (T0), before and after (T1 and T2, respectively) jogging uphill or downhill, and 1 day after (T3) jogging. Additionally, the Δ-value was calculated using the change of meniscus after efforts as the difference in MME between T1 and T2. RESULTS: The MME in T2 was significantly greater than those in T0 and T1. Conversely, the MME in T3 was significantly lesser than that in T2. No significant difference was found between those in T0 and T1, and T3. ΔMME exhibited a significant positive correlation with the cumulative KAM (r = 0.68, p = 0.01), but not for peak KAM. CONCLUSION: The temporary reaction of MME observed in ultrasound correlates with the cumulative stress of KAM.


Asunto(s)
Meniscos Tibiales , Osteoartritis de la Rodilla , Masculino , Humanos , Adulto Joven , Adulto , Meniscos Tibiales/diagnóstico por imagen , Trote , Estudios de Cohortes , Voluntarios Sanos
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