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1.
Artículo en Inglés | MEDLINE | ID: mdl-38951110

RESUMEN

Differentiation of induced pluripotent stem cells (iPSCs) is an extremely complex process that has proven difficult to study. In this research, we utilized nanotopography to elucidate details regarding iPSC differentiation by developing a nanodot platform consisting of nanodot arrays of increasing diameter. Subjecting iPSCs cultured on the nanodot platform to a cardiomyocyte (CM) differentiation protocol revealed several significant gene expression profiles that were associated with poor differentiation. The observed expression trends were used to select existing small-molecule drugs capable of modulating differentiation efficiency. BRD K98 was repurposed to inhibit CM differentiation, while iPSCs treated with NSC-663284, carmofur, and KPT-330 all exhibited significant increases in not only CM marker expression but also spontaneous beating, suggesting improved CM differentiation. In addition, quantitative polymerase chain reaction was performed to determine the gene regulation responsible for modulating differentiation efficiency. Multiple genes involved in extracellular matrix remodeling were correlated with a CM differentiation efficiency, while genes involved in the cell cycle exhibited contrasting expression trends that warrant further studies. The results suggest that expression profiles determined via short time-series expression miner analysis of nanodot-cultured iPSC differentiation can not only reveal drugs capable of enhancing differentiation efficiency but also highlight crucial sets of genes related to processes such as extracellular matrix remodeling and the cell cycle that can be targeted for further investigation. Our findings confirm that the nanodot platform can be used to reveal complex mechanisms behind iPSC differentiation and could be an indispensable tool for optimizing iPSC technology for clinical applications.

2.
Bioengineering (Basel) ; 11(6)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38927794

RESUMEN

The vertebral cage has been widely used in posterior lumbar interbody fusion. The risk of cage dislodgment is high for patients undergoing lumbar fusion surgery. Therefore, the main objective of this study was to use a lumbar fusion model to investigate the effects of cage dislodgment on different cage arrangements after PLIF. Finite element analysis was used to compare three PEEK cage placements, together with the fibula-type cage, with respect to the four kinds of lumbar movements. The results revealed that a horizontal cage arrangement could provide a better ability to resist cage dislodgment. Overall lumbar flexion movements were confirmed to produce a greater amount of cage slip than the other three lumbar movements. The lower part of the lumbar fusion segment could create a greater amount of cage dislodgment for all of the lumbar movements. Using an autograft with a fibula as a vertebral cage cannot effectively reduce cage dislodgment. Considering the maximum movement type in lumbar flexion, we suggest that a horizontal arrangement of the PEEK cage might be considered when a single PEEK cage is placed in the fusion segment, as doing so can effectively reduce the extent of cage dislodgment.

3.
Bioengineering (Basel) ; 11(6)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38927828

RESUMEN

Bone drilling is a common procedure used to create pilot holes for inserting screws to secure implants for fracture fixation. However, this process can increase bone temperature and the excessive heat can lead to cell death and thermal osteonecrosis, potentially causing early fixation failure or complications. We applied a three-dimensional dynamic elastoplastic finite element model to evaluate the propagation and distribution of heat during bone drilling and assess the thermally affected zone (TAZ) that may lead to thermal necrosis. This model investigates the parameters influencing bone temperature during bone drilling, including drill diameter, rotational speed, feed force, and predrilled hole. The results indicate that our FE model is sufficiently accurate in predicting the temperature rise effect during bone drilling. The maximum temperature decreases exponentially with radial distance. When the feed forces are 40 and 60 N, the maximum temperature does not exceed 45 °C. However, with feed forces of 10 and 20 N, both the maximum temperatures exceed 45 °C within a radial distance of 0.2 mm, indicating a high-risk zone for potential thermal osteonecrosis. With the two-stage drilling procedure, where a 2.5 mm pilot hole is predrilled, the maximum temperature can be reduced by 14 °C. This suggests that higher feed force and rotational speed and/or using a two-stage drilling process could mitigate bone temperature elevation and reduce the risk of thermal osteonecrosis during bone drilling.

4.
Stem Cell Res Ther ; 15(1): 163, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853252

RESUMEN

BACKGROUND: A rising population faces challenges with healing-impaired cutaneous wounds, often leading to physical disabilities. Adipose-derived stem cells (ASCs), specifically in the cell sheet format, have emerged as a promising remedy for impaired wound healing. Human platelet lysate (HPL) provides an attractive alternative to fetal bovine serum (FBS) for culturing clinical-grade ASCs. However, the potential of HPL sheets in promoting wound healing has not been fully investigated. This study aimed to explore the anti-fibrotic and pro-angiogenic capabilities of HPL-cultured ASC sheets and delve into the molecular mechanism. METHODS: A rat burn model was utilized to evaluate the efficacy of HPL-cultured ASC sheets in promoting wound healing. ASC sheets were fabricated with HPL, and those with FBS were included for comparison. Various analyses were conducted to assess the impact of HPL sheets on wound healing. Histological examination of wound tissues provided insights into aspects such as wound closure, collagen deposition, and overall tissue regeneration. Immunofluorescence was employed to assess the presence and distribution of transplanted ASCs after treatment. Further in vitro studies were conducted to decipher the specific factors in HPL sheets contributing to angiogenesis. RESULTS: HPL-cultured ASC sheets significantly accelerated wound closure, fostering ample and organized collagen deposition in the neo-dermis. Significantly more retained ASCs were observed in wound tissues treated with HPL sheets compared to the FBS counterparts. Moreover, HPL sheets mitigated macrophage recruitment and decreased subsequent wound tissue fibrosis in vivo. Immunohistochemistry also indicated enhanced angiogenesis in the HPL sheet group. The in vitro analyses showed upregulation of C-C motif chemokine ligand 5 (CCL5) and angiogenin in HPL sheets, including both gene expression and protein secretion. Culturing endothelial cells in the conditioned media compared to media supplemented with CCL5 or angiogenin suggested a correlation between CCL5 and the pro-angiogenic effect of HPL sheets. Additionally, through neutralizing antibody experiments, we further validated the crucial role of CCL5 in HPL sheet-mediated angiogenesis in vitro. CONCLUSIONS: The present study underscores CCL5 as an essential factor in the pro-angiogenic effect of HPL-cultured ASC sheets during the wound healing process. These findings highlight the potential of HPL-cultured ASC sheets as a promising therapeutic option for healing-impaired cutaneous wounds in clinical settings. Furthermore, the mechanism exploration yields valuable information for optimizing regenerative strategies with ASC products. BRIEF ACKNOWLEDGMENT: This research was supported by the National Science and Technology Council, Taiwan (NSTC112-2321-B-002-018), National Taiwan University Hospital (111C-007), and E-Da Hospital-National Taiwan University Hospital Joint Research Program (111-EDN0001, 112-EDN0002).


Asunto(s)
Tejido Adiposo , Plaquetas , Quimiocina CCL5 , Neovascularización Fisiológica , Cicatrización de Heridas , Animales , Humanos , Ratas , Plaquetas/metabolismo , Quimiocina CCL5/metabolismo , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Células Madre/metabolismo , Células Madre/citología , Ratas Sprague-Dawley , Células Cultivadas , Masculino , Trasplante de Células Madre/métodos , Angiogénesis
5.
J Hand Surg Eur Vol ; : 17531934241258301, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833546

RESUMEN

We studied the outcome of dorsal spanning plate for complex carpometacarpal fracture-dislocation management as a feasible option in nine patients, even on delayed presentation with substantial metacarpal shortening. However, patients must be informed about the need for plate removal.

6.
World Neurosurg ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38735563

RESUMEN

OBJECTIVE: Spinal cord injury (SCI) is a devastating condition that significantly decreases the patient's quality of life. Therefore, treatments that can facilitate nerve regeneration, reduce complications, and increase quality of life are valuable for these patients. In this study, we aimed to assess nerve bypass surgery's feasibility and clinical outcomes by transferring the intercostal nerves (ICNs) into the spinal cord. METHODS: Eight patients with complete thoracic SCI and delayed presentation more than a year after the injury were analyzed retrospectively. All patients underwent nerve bypass surgery with the transfer of two pairs of ICNs from proximal to the injury site to the anterolateral spinal cord, followed by duraplasty with fascia grafting to close the dura. RESULTS: Six of the eight (75%) patients demonstrated motor and sensory improvements, based on the American Spinal Cord Injury Association score. Three patients demonstrated a limited recovery of motor function that could be independently triggered without ICN initiation. Five patients demonstrated evidence of cerebrospinal fluid (CSF) leakage after surgery; however, only one patient complained of a headache. CONCLUSION: Spinal cord bypass surgery is a potential reconstruction method to treat chronic complete thoracic SCI with functional improvements, and is worth further investigation.

7.
Front Genet ; 15: 1365729, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818036

RESUMEN

Background: Muscular dystrophies and congenital myopathies encompass various inherited muscular disorders that present diagnostic challenges due to clinical complexity and genetic heterogeneity. Methods: This study aimed to investigate the use of whole exome sequencing (WES) in diagnosing muscular disorders in pediatric patients in Taiwan. Out of 161 pediatric patients suspected to have genetic/inherited myopathies, 115 received a molecular diagnosis through conventional tests, single gene testing, and gene panels. The remaining 46 patients were divided into three groups: Group 1 (multiplex ligation-dependent probe amplification-negative Duchenne muscular dystrophy) with three patients (6.5%), Group 2 (various forms of muscular dystrophies) with 21 patients (45.7%), and Group 3 (congenital myopathies) with 22 patients (47.8%). Results: WES analysis of these groups found pathogenic variants in 100.0% (3/3), 57.1% (12/21), and 68.2% (15/22) of patients in Groups 1 to 3, respectively. WES had a diagnostic yield of 65.2% (30 patients out of 46), detecting 30 pathogenic or potentially pathogenic variants across 28 genes. Conclusion: WES enables the diagnosis of rare diseases with symptoms and characteristics similar to congenital myopathies and muscular dystrophies, such as muscle weakness. Consequently, this approach facilitates targeted therapy implementation and appropriate genetic counseling.

8.
Diagnostics (Basel) ; 14(8)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38667491

RESUMEN

Congenital heart defects (CHDs) affect a substantial proportion of patients with Kabuki syndrome. However, the prevalence and type of CHD and the genotype-phenotype correlations in Asian populations are not fully elucidated. This study performed a retrospective analysis of 23 Taiwanese patients with molecularly confirmed Kabuki syndrome. Twenty-two patients presented with pathogenic variants in the KMT2D gene. Comprehensive clinical assessments were performed. A literature review was conducted to summarize the spectrum of CHDs in patients with Kabuki syndrome. In total, 16 (73.9%) of 22 patients with pathogenic KMT2D variants had CHDs. The most common types of CHD were atrial septal defects (37.5%), ventricular septal defects (18.8%), coarctation of the aorta (18.8%), bicuspid aortic valve (12.5%), persistent left superior vena cava (12.5%), mitral valve prolapse (12.5%), mitral regurgitation (12.5%), and patent ductus arteriosus (12.5%). Other cardiac abnormalities were less common. Further, there were no clear genotype-phenotype correlations found. A literature review revealed similar patterns of CHDs, with a predominance of left-sided obstructive lesions and septal defects. In conclusion, the most common types of CHDs in Taiwanese patients with Kabuki syndrome who presented with KMT2D mutations are left-sided obstructive lesions and septal defects.

9.
World Neurosurg ; 184: e511-e517, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38316175

RESUMEN

OBJECTIVE: The management of postoperative deep infection after anterior cervical discectomy and fusion (ACDF) remains challenging for spine surgeons. Our institution uses handmade antibiotic-loaded cement spacers to treat these complex cases. This study aimed to determine the efficacy and feasibility of this treatment. METHODS: This study included 4 patients with deep cervical spine infections after ACDF who underwent our treatment between March 2012 and January 2022. Patients' laboratory data, visual analog scale scores, comorbidities, complications, and neurological status were recorded. Their clinical conditions were also evaluated based on the Neck Disability Index, Japanese Orthopaedic Association score, and Odom criteria. RESULTS: Infection eradication was achieved in all patients after treatment. The average preoperative visual analog scale score was 7.5 (range: 7-8); this decreased to 1.25 (range: 1-2) at 1 year postoperatively. None of the patients experienced severe complications, such as neurological deterioration or bone graft dislodgement. The Neck Disability Index improved from a preoperative value of 54% (range: 48-60%) to 6% (range: 4-8%) at 1 year postoperatively. The Japanese Orthopaedic Association score improved from a preoperative score of 10.25 (range: 10-11)-14.75 (range: 14-16) at 1 year postoperatively. All patients achieved excellent outcomes based on Odom criteria at 1 year postoperatively. CONCLUSIONS: Good clinical outcomes were achieved in this study. Although 2-stage surgery is required, this technique could be an alternative for patients with postoperative deep infection after ACDF.


Asunto(s)
Discectomía , Fusión Vertebral , Humanos , Resultado del Tratamiento , Discectomía/métodos , Vértebras Cervicales/cirugía , Complicaciones Posoperatorias/etiología , Trasplante Óseo , Fusión Vertebral/métodos , Estudios Retrospectivos
10.
Int J Med Sci ; 21(1): 8-18, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38164354

RESUMEN

Background: Silver-Russell syndrome (SRS; OMIM #180860) is a clinically and genetically heterogeneous imprinting disorder characterized by prenatal and postnatal growth failure. The aim of this study was to identify the epigenotype-phenotype correlations in these patients using quantitative DNA methylation analysis. Methods: One hundred and eighty-three subjects clinically suspected of having SRS were referred for diagnostic testing by the methylation profiling of H19-associated imprinting center (IC) 1 and imprinted PEG1/MEST regions using methylation-specific high-resolution melting analysis and methylation quantification with the MassARRAY assay. Correlations between quantitative DNA methylation status and clinical manifestations of the subjects according to the Netchine-Harbison (N-H) clinical scoring system for SRS were analyzed. Results: Among the 183 subjects, 90 had a clinical diagnosis of SRS [N-H score ≥ 4 (maximum = 6)] and 93 had an SRS score < 4. Molecular lesions were detected in 41% (37/90) of the subjects with a clinical diagnosis of SRS, compared with 3% (3/93) of those with an N-H score < 4. The IC1 methylation level was negatively correlated with the N-H score. The molecular diagnosis rate was positively correlated with the N-H score. Thirty-one subjects had IC1 hypomethylation (IC1 methylation level <35% by the MassARRAY assay), seven had maternal uniparental disomy 7, and two had pathogenic copy number variants. Among the 90 subjects with an N-H score ≥ 4, the IC1 methylation level was significantly different between those with or without some clinical SRS features, including birth length ≤ 10th centile, relative macrocephaly at birth, normal cognitive development, body asymmetry, clinodactyly of the fifth finger, and genital abnormalities. Conclusions: This study confirmed the suitability of the N-H clinical scoring system as clinical diagnostic criteria for SRS. Quantitative DNA methylation analysis using the MassARRAY assay can improve the detection of epigenotype-phenotype correlations, further promoting better genetic counseling and multidisciplinary management for these patients.


Asunto(s)
Trastornos de Impronta , Síndrome de Silver-Russell , Recién Nacido , Femenino , Embarazo , Humanos , Síndrome de Silver-Russell/diagnóstico , Síndrome de Silver-Russell/genética , Síndrome de Silver-Russell/patología , Metilación de ADN/genética , Fenotipo , Disomía Uniparental/genética
11.
Carbohydr Polym ; 329: 121767, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38286542

RESUMEN

Although starch-protein interactions have been widely used to regulate starch digestibility and retrogradation during food processings, their synchronous regulating effects on both properties still remain largely unexplored. The effects of interactions with pea protein (PP) under thermal shear processing on the digestion and retrogradation properties of modified chestnut starch were investigated. Results show that thermal shear processing broke starch multi-scale structure, leading to the reduction in molar mass, short-range ordered structure, crystallinity, and starch compactness, in turn increasing starch digestibility and accelerating starch retrogradation. However, PP molecules would interact with chestnut starch through hydrogen bonding to form the starch-protein complexes during thermal shear processing, which caused an increased resistant starch. These starch-protein interactions also inhibited the formation of short-range, long-range ordered structure, aggregate structure during storage, causing a reduced degree of retrogradation. The results provided new insights into the synchronously regulating effects of starch-protein interactions under thermal shear processing on starch digestion and retrogradation, which would facilitate the development of starch-based foods with high nutrition and quality.


Asunto(s)
Manipulación de Alimentos , Almidón , Almidón/química , Almidón Resistente , Nueces , Digestión
13.
Int J Gynaecol Obstet ; 165(2): 655-665, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38010285

RESUMEN

OBJECTIVE: To evaluate the metastatic pattern, identify the risk factors, and establish a nomogram for predicting prognosis of endometrial cancer (EC) with distant metastasis. METHODS: A retrospective cohort study of women diagnosed with EC was conducted according to the Surveillance, Epidemiology, and End Results (SEER) database during 2010-2017. Multivariate logistic analysis and Cox analysis were performed to identify the risk factors in promoting distant metastasis and predictors associated with overall survival (OS) in this particular subpopulation. A nomogram was then constructed and validated by the concordance index (C-index), the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analysis. RESULTS: A total of 2799 cases of distant metastasis in EC patients were identified, with an overall incidence rate of 3.74% from 2010 to 2017. Black race, unmarried status, non-endometrioid histologic types, and grade IV were significant risk factors for distant metastasis in EC patients. Meanwhile, race, histology, grade, metastasis status, surgery, lymphadenectomy, and chemotherapy were identified as independent prognostic factors for OS. A nomogram to predict 1-, 3-, and 5-year OS was established, and presented favorable accuracy and clinical applicability. Patients were further divided into high- and low-risk groups according to the model. CONCLUSION: The nomogram was developed as a highly accurate, individualized tool to better predict the prognosis of EC patients with distant metastasis, which would help clinicians to identify high-risk patients, and adjust and tailor their treatment strategies.


Asunto(s)
Neoplasias Endometriales , Nomogramas , Humanos , Femenino , Pronóstico , Incidencia , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Endometriales/epidemiología , Neoplasias Endometriales/terapia , Programa de VERF
14.
Biomed Pharmacother ; 170: 116006, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38091640

RESUMEN

Rheumatoid arthritis (RA) is a chronic inflammatory condition known for its irreversible destructive impact on the joints. Chondrocytes play a pivotal role in the production and maintenance of the cartilage matrix. However, the presence of inflammatory cytokines can hinder chondrocyte proliferation and promote apoptosis. Isoliquiritigenin (ISL), a flavonoid, potentially exerts protective effects against various inflammatory diseases. However, its specific role in regulating the nuclear factor E2-associated factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in chondrocytes in RA remains unclear. To investigate this, this study used human chondrocytes and Sprague-Dawley rats to construct in vitro and in vivo RA models, respectively. The study findings reveal that cytokines markedly induced oxidative stress, the activation of matrix metalloproteinases, and apoptosis both in vitro and in vivo. Notably, ISL treatment significantly mitigated these effects. Moreover, Nrf2 or HO-1 inhibitors reversed the protective effects of ISL, attenuated the expression of Nrf2/HO-1 and peroxisome proliferator-activated receptor gamma-coactivator-1α, and promoted chondrocyte apoptosis. This finding indicates that ISL primarily targets the Nrf2/HO-1 pathway in RA chondrocytes. Moreover, ISL treatment led to improved behavior scores, reduced paw thickness, and mitigated joint damage as well as ameliorated oxidative stress in skeletal muscles in an RA rat model. In conclusion, this study highlights the pivotal role of the Nrf2/HO-1 pathway in the protective effects of ISL and demonstrates the potential of ISL as a treatment option for RA.


Asunto(s)
Artritis Reumatoide , Hemo-Oxigenasa 1 , Ratas , Humanos , Animales , Hemo-Oxigenasa 1/metabolismo , Condrocitos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Ratas Sprague-Dawley , Estrés Oxidativo , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Citocinas/metabolismo , Apoptosis
16.
Injury ; 55(2): 111012, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38041925

RESUMEN

Brachial plexus injuries (BPI) contribute not only to physical dysfunction but also to socioeconomic aspects and psychological disability. Patients with total arm-type BPI will lose not only the shoulder and elbow function but also the hand function, making reconstruction particularly challenging. Reconstructive procedures commonly include nerve repair, grafting, neurotization (nerve transfer), tendon transfer and free functional muscle transfer (FFMT). Although it is difficult to achieve prehensile hand function, most of patients with total arm-type BPI can be treated with satisfied outcomes. In addition to surgical techniques, comprehensive rehabilitation is another important factor for successful outcomes, and efficient communication can help to boost patient morale and eliminate uncertainty.


Asunto(s)
Neuropatías del Plexo Braquial , Plexo Braquial , Articulación del Codo , Transferencia de Nervios , Adulto , Humanos , Brazo , Plexo Braquial/cirugía , Plexo Braquial/lesiones , Neuropatías del Plexo Braquial/cirugía , Codo , Articulación del Codo/cirugía , Transferencia de Nervios/métodos , Resultado del Tratamiento
17.
Arch Orthop Trauma Surg ; 144(2): 927-935, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37803086

RESUMEN

INTRODUCTION: Most of the reported discussions about the learning curve for the direct anterior approach (DAA) in total hip arthroplasty (THA) have been by experienced surgeons. The study's aim was to describe the learning curve, short-term outcomes, complications, and adaptations to the DAA used in the first 100 THA cases experienced by a young surgeon who had received DAA training for trauma surgeries. MATERIALS AND METHODS: This retrospective study summarizes the first 100 consecutive cases experienced by a young surgeon who performed the unilateral DAA for THA between 2019 and 2021. Cumulative sum (CUSUM) analysis was performed to evaluate the learning curve on the basis of operative time and overall complications. The demographics data, short-term outcomes, and complications of the first 50 and second 50 cases were compared. RESULTS: The CUSUM curve declined after 49 and 55 cases, measured by operative time and overall complications, respectively. The median operative time (104 vs. 80 min) and intraoperative fluoroscopic time (38 vs. 12 s) increased significantly in the first 50 cases compared with the times in the second 50 cases. Complications tended to occur in the first 50 cases (12% vs. 6%), and the overall rate was 9%. Major complications all occurred in the first 50 cases, with a rate of 4%. Only one case, which involved a complicated periprosthetic fracture around the stem that extended to the tip, required the intervention of a senior surgeon. CONCLUSIONS: Even after receiving training on the DAA for trauma surgeries, the young surgeon experienced a steep learning curve and more complications in the first 50 cases. The DAA for THA is a technically demanding procedure and may require guidance from an experienced surgeon to manage unexpected complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Fracturas Óseas , Cirujanos , Humanos , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Estudios Retrospectivos , Curva de Aprendizaje , Fracturas Óseas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
18.
Life (Basel) ; 13(11)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-38004250

RESUMEN

The locking plate may provide improved fixation in osteoporotic bone; however, it has been reported to fail due to varus collapse or screw perforation of the articular surface, especially in osteoporotic bone with medial cortex comminution. Using bone graft as an intramedullary strut together with plate fixation may result in a stronger construct. However, the drawbacks of bone grafts include limited supply, high cost, and infection risk. PMMA (so-called bone cement) has been widely used for implant fixation due to its good mechanical properties, fabricability, and biocompatibility. The risk of donor-site infection and the drawbacks of allografting may be overcome by considering PMMA struts as alternatives to fibular grafts for humeral intramedullary grafting surgeries. However, the potential effects of intramedullary PMMA strut on the dynamic behaviour of osteoporotic humerus fractures remain unclear. This study aimed to investigate the influence of an intramedullary PMMA strut on the stability of unstable proximal humeral fractures in an osteoporotic synthetic model. Two fixation techniques, a locking plate alone (non-strut group) and the same fixation augmented with an intramedullary PMMA strut (with-strut group), were cyclically tested in 20 artificial humeral models. Axially cyclic testing was performed to 450 N for 10,000 cycles, intercyclic motion, cumulated fragment migration, and residual deformation of the constructs were determined at periodic cyclic intervals, and the groups were compared. Results showed that adding an intramedullary PMMA strut could decrease 1.6 times intercyclic motion, 2 times cumulated fracture gap migration, and 1.8 times residual deformation from non-strut fixation. During cycling, neither screw pull-out, cut-through, nor implant failure was observed in the strut-augmented group. We concluded that the plate-strut mechanism could enhance the cyclic stability of the fixation and minimize the residual displacement of the fragment in treating osteoporotic proximal humeral unstable fractures. The PMMA strut has the potential to substitute donor bone and serve as an intramedullary support when used in combination with locking plate fixation. The intramedullary support with bone cement can be considered a solution in the treatment of osteoporotic proximal humeral fractures, especially when there is medial comminution.

19.
Int J Med Sci ; 20(11): 1377-1385, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37790845

RESUMEN

Background: 22q11.2 deletion syndrome (22q11.2DS) is a microdeletion syndrome exhibiting significant clinical phenotype variability. This study aimed to investigate the clinical features, immune profiles, and cognitive abilities of 22q11.2DS patients receiving treatment at MacKay Memorial Hospital in Taipei, Taiwan. Methods: This is a cross-sectional analysis between January 2001 and December 2022. We recruited 27 patients with 22q11.2DS using fluorescence in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (aCGH). Our evaluation included patient history, physical examination, laboratory analysis, and cardiac and cognitive assessment. Results: We included 27 patients with 22q11.2DS, 7 (25.9%) of whom were female. The median age of the patients was 17.9 yr. Ninety-three percent of the patients exhibited the characteristic facial features associated with the syndrome. A family history of 22q11.2DS was found in 11.1% of the patients. Furthermore, 74.1% of the patients had a congenital heart defect, the most common of which was tetralogy of Fallot (40.7%). Hypocalcemia was observed in 40.7% of the patients. A low T-cell count was observed in 66.7% of the patients, whereas 18.5% had low immunoglobulin levels. Cognitive assessments revealed that four out of six evaluated patients (66.7%) had an intellectual disability, as evidenced by intellectual quotient scores less than 70. The remaining two patients (33.3%) had a borderline intellectual function. Conclusion: Tetralogy of Fallot, hypocalcemia, immunologic defects, and cognitive impairment were common among our patients. To address the potential multisystem involvement, we recommend that all affected individuals undergo a comprehensive evaluation by a multidisciplinary care team.


Asunto(s)
Síndrome de DiGeorge , Cardiopatías Congénitas , Hipocalcemia , Tetralogía de Fallot , Humanos , Femenino , Masculino , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/diagnóstico , Tetralogía de Fallot/genética , Hipocalcemia/genética , Hibridación Fluorescente in Situ , Taiwán/epidemiología , Estudios Transversales , Hibridación Genómica Comparativa , Cardiopatías Congénitas/genética , Sistema Inmunológico , Deleción Cromosómica
20.
J Appl Physiol (1985) ; 135(6): 1268-1283, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37855033

RESUMEN

Cervical spinal cord injury interrupts supraspinal pathways innervating thoracic sympathetic preganglionic neurons and results in cardiovascular dysfunction. Both respiratory and locomotor functions were also impaired due to damages of motoneuron pools controlling respiratory and forelimb muscles, respectively. However, no study has investigated autonomic and somatic motor functions in the same animal model. The present study aimed to establish a cervical spinal cord injury model to evaluate cardiorespiratory response and locomotor activity in unanesthetized rats. Cardiovascular response and respiratory behavior following laminectomy or cervical spinal contusion were measured using noninvasive blood pressure analyzer and plethysmography systems, respectively. Locomotor activity was evaluated by an open-field test and a locomotor rating scale. The results demonstrated that mean arterial blood pressure and heart rate were significantly reduced in contused rats compared with uninjured rats at the acute injured stage. Tidal volume was also significantly reduced during the acute and subchronic stages. Moreover, locomotor function was severely impaired, evidenced by decreasing moving ability and locomotor rating scores from the acute to chronic injured stages. Retrograde neurotracer results revealed that cervical spinal cord injury caused a reduction in number of phrenic and triceps motoneurons. Immunofluorescence staining revealed a significant attenuation of serotonergic, noradrenergic, glutamatergic, and GABAergic fibers innervating the thoracic sympathetic preganglionic neurons in chronically contused rats. These results revealed the pathological mechanism underlying the comorbidity of cardiorespiratory and locomotor dysfunction following cervical spinal cord injury. We proposed that this animal model can be used to evaluate the therapeutic efficacy of potential strategies to improve different physiological functions.NEW & NOTEWORTHY The present study establishes a preclinical rodent model to comprehensively investigate physiological functions under unanesthetized condition following cervical spinal cord contusion. The results demonstrated that cervical spinal cord contusion is associated with impairments in cardiovascular, respiratory, and locomotor function. Respiratory and forelimb motoneurons and neurochemical innervations of sympathetic preganglionic neurons were damaged following injury. This animal model can be used to evaluate the therapeutic efficacy of potential strategies to improve different physiological functions.


Asunto(s)
Médula Cervical , Traumatismos de la Médula Espinal , Ratas , Animales , Ratas Sprague-Dawley , Médula Cervical/lesiones , Médula Espinal , Comorbilidad , Vértebras Cervicales
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