scholarly journals Advances and Prospects in Tissue-Engineered Meniscal Scaffolds for Meniscus Regeneration

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Weimin Guo ◽  
Shuyun Liu ◽  
Yun Zhu ◽  
Changlong Yu ◽  
Shibi Lu ◽  
...  

The meniscus plays a crucial role in maintaining knee joint homoeostasis. Meniscal lesions are relatively common in the knee joint and are typically categorized into various types. However, it is difficult for inner avascular meniscal lesions to self-heal. Untreated meniscal lesions lead to meniscal extrusions in the long-term and gradually trigger the development of knee osteoarthritis (OA). The relationship between meniscal lesions and knee OA is complex. Partial meniscectomy, which is the primary method to treat a meniscal injury, only relieves short-term pain; however, it does not prevent the development of knee OA. Similarly, other current therapeutic strategies have intrinsic limitations in clinical practice. Tissue engineering technology will probably address this challenge by reconstructing a meniscus possessing an integrated configuration with competent biomechanical capacity. This review describes normal structure and biomechanical characteristics of the meniscus, discusses the relationship between meniscal lesions and knee OA, and summarizes the classifications and corresponding treatment strategies for meniscal lesions to understand meniscal regeneration from physiological and pathological perspectives. Last, we present current advances in meniscal scaffolds and provide a number of prospects that will potentially benefit the development of meniscal regeneration methods.

2013 ◽  
Vol 9 (1) ◽  
pp. 96-102 ◽  
Author(s):  
Luigi Mazzone ◽  
Valentina Postorino ◽  
Laura Reale ◽  
Manuela Guarnera ◽  
Valeria Mannino ◽  
...  

Background: Several recent studies investigated the relationship between self-esteem and ADHD, however, the results are still controversial. In the present study we analyze the characteristics of self-esteem in a sample of children and adolescents suffering from ADHD, with a particular focus on the relationship between ADHD symptoms severity and treatment strategies. Methods: A total of 85 patients with ADHD (44 drug-free and 41 drug-treated, 23 of which atomoxetine-treated and 18 Methylphenidate-treated) and 26 healthy controls were enrolled in the study in order to evaluate self-esteem using the Self-esteem Multidimensional Test (TMA). Results: ADHD subjects revealed lower scores on all self-esteem domains compared to controls. Both ADHD drug-free (47.1%) and ADHD drug-treated (44.1%) groups showed significantly higher rates of subjects in the pathological range as compared to normal control group (8.8%) (p <.001) with a higher percentage of subjects in the pathological range. Among ADHD drug-treated subjects, the methylphenidate group showed higher self-esteem scores as compared to the atomoxetine group. Conclusion: A lower self-esteem profile is more common in subjects suffering from ADHD than in healthy controls, suggesting the importance of an early detection of psychological well-being in these children in order to reduce the ADHD symptoms long-term impacts.


2020 ◽  
Vol 11 ◽  
Author(s):  
Yi Li ◽  
Lu Yin ◽  
Zhongmin Fan ◽  
Binxiao Su ◽  
Yu Chen ◽  
...  

Neurological dysfunction, one of the severe manifestations of sepsis in patients, is closely related to increased mortality and long-term complications in intensive care units, including sepsis-associated encephalopathy (SAE) and chronic pain. The underlying mechanisms of these sepsis-induced neurological dysfunctions are elusive. However, it has been well established that microglia, the dominant resident immune cell in the central nervous system, play essential roles in the initiation and development of SAE and chronic pain. Microglia can be activated by inflammatory mediators, adjacent cells and neurotransmitters in the acute phase of sepsis and then induce neuronal dysfunction in the brain. With the spotlight focused on the relationship between microglia and sepsis, a deeper understanding of microglia in SAE and chronic pain can be achieved. More importantly, clarifying the mechanisms of sepsis-associated signaling pathways in microglia would shed new light on treatment strategies for SAE and chronic pain.


2019 ◽  
Vol 12 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Meltem Özdemir ◽  
Rasime Kavak

Objective: This study evaluated the prevalence of different types of meniscal lesions among elderly patients with knee pain. Moreover, this study assessed the relationship between meniscal lesions and the presence of radiographic knee osteoarthritis (OA) in the elderly population. Methods: The radiographs and magnetic resonance images of one knee out of 306 patients with knee pain aged 65-89 years were reviewed for knee OA and meniscal lesions. The prevalence of different types of meniscal lesions was calculated, and the relationship between the prevalence of meniscal lesion types and the presence of radiographic knee OA was analyzed. Results: Among 306 participants, 274 (89.5%) showed radiographic knee OA. We found one or more meniscal lesion(s) in 93% of the total subjects, in 94% of all patients with knee OA, and in 84% of all patients without knee OA. The prevalence of surgically target, possible-target, and nontarget lesions were 24%, 72%, and 69%, respectively. The prevalence of surgically target lesions was significantly higher in patients with knee OA than in those without it. The most common lesion observed was meniscal extrusion, followed by the horizontal and complex meniscal tears. Conclusions: Our results demonstrated that meniscal damage is considerably prevalent among elderly individuals with knee pain, especially in those with knee OA. The fact that surgically target and possible-target lesions constitute a substantial proportion of these lesions should be considered in the clinical approach to these patients.


Author(s):  
Amjad Waheed Yousuf ◽  
Awhad Mueed Yousuf ◽  
Aasiy Ul Erum

Knee Osteoarthritis (OA) is a major cause of pain and disability worldwide. In majority of cases of knee OA the etiology remains unidentified, however, a number of systemic and local biomechanical factors have been associated with the increased risk of this disorder. These factors may determine the onset of knee OA and rapidity with which the disorder progresses. Occupation and sports participation are among the commonly implicated risk factors and have been studied in detail for their relationship with knee OA. An increased risk of knee OA has been observed in people who are involved in jobs requiring bending and kneeling of the knee joint. Likewise, persons who participate in sports involving excessive strain of the knee joint also carry a higher risk of development of this disorder in the later part of their life. In this review we present the data, obtained from original resources, determining the relationship between occupation and sports participation with the onset and progression of knee OA.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12509
Author(s):  
Karol Daszkiewicz ◽  
Piotr Łuczkiewicz

Background Increased mechanical loading and pathological response of joint tissue to the abnormal mechanical stress can cause degradation of cartilage characteristic of knee osteoarthritis (OA). Despite osteoarthritis is risk factor for the development of meniscal lesions the mechanism of degenerative meniscal lesions is still unclear. Therefore, the aim of the study is to investigate the influence of medial compartment knee OA on the stress state and deformation of the medial meniscus. Methods The finite element method was used to simulate the stance phase of the gait cycle. An intact knee model was prepared based on magnetic resonance scans of the left knee joint of a healthy volunteer. Degenerative changes in the medial knee OA model were simulated by nonuniform reduction in articular cartilage thickness in specific areas and by a decrease in the material parameters of cartilage and menisci. Two additional models were created to separately evaluate the effect of alterations in articular cartilage geometry and material parameters of the soft tissues on the results. A nonlinear dynamic analysis was performed for standardized knee loads applied to the tibia bone. Results The maximum von Mises stress of 26.8 MPa was observed in the posterior part of the medial meniscus body in the OA model. The maximal hoop stress for the first peak of total force was 83% greater in the posterior horn and only 11% greater in the anterior horn of the medial meniscus in the OA model than in the intact model. The reduction in cartilage thickness caused an increase of 57% in medial translation of the medial meniscus body. A decrease in the compressive modulus of menisci resulted in a 2.5-fold greater reduction in the meniscal body width compared to the intact model. Conclusions Higher hoop stress levels on the inner edge of the posterior part of the medial meniscus in the OA model than in the intact model are associated with a greater medial translation of the meniscus body and a greater reduction in its width. The considerable increase in hoop stresses shows that medial knee OA may contribute to the initiation of meniscal radial tears.


Author(s):  
Brajesh Dadarya ◽  
Ashish Sirsikar ◽  
Ashok Vidyarthi

<p class="abstract"><strong>Background:</strong> The relationship between joint pain and osteoarthritis is poorly understood, however, the most common patterns associated with knee osteoarthritis are diffuse or medial joint pain. The objective of the study was to test the sensitivity of medial knee joint pain for the diagnosis of mild knee osteoarthritis, and thence its relationship.</p><p class="abstract"><strong>Methods:</strong> This is a prospective analytical study of 124 patients visiting to our out-patient setup in the year 2017, with complaint of medial knee joint pain, which after thorough clinical examination, were investigated radiologically.<strong></strong></p><p class="abstract"><strong>Results:</strong> In our study of 124 patients, there were 69 female (55.5%) and 55 male (47.5%), with a mean age of 59.3 years. The average duration of symptoms was 3.2 years, and the average VAS for severity of pain was 59.3. The sensitivity of medial knee joint pain for mild OA was thus calculated to be 79.8%.</p><p><strong>Conclusions:</strong> Medial knee joint pain is a very important symptom to raise a suspicion and also to warrant further radiological investigation for the early diagnosis and management of knee OA.</p>


Author(s):  
José G. Centeno

Abstract The steady increase in linguistic and cultural diversity in the country, including the number of bilingual speakers, has been predicted to continue. Minorities are expected to be the majority by 2042. Strokes, the third leading cause of death and the leading cause of long-term disability in the U.S., are quite prevalent in racial and ethnic minorities, so population estimates underscore the imperative need to develop valid clinical procedures to serve the predicted increase in linguistically and culturally diverse bilingual adults with aphasia in post-stroke rehabilitation. Bilingualism is a complex phenomenon that interconnects culture, cognition, and language; thus, as aphasia is a social phenomenon, treatment of bilingual aphasic persons would benefit from conceptual frameworks that exploit the culture-cognition-language interaction in ways that maximize both linguistic and communicative improvement leading to social re-adaptation. This paper discusses a multidisciplinary evidence-based approach to develop ecologically-valid treatment strategies for bilingual aphasic individuals. Content aims to spark practitioners' interest to explore conceptually broad intervention strategies beyond strictly linguistic domains that would facilitate linguistic gains, communicative interactions, and social functioning. This paper largely emphasizes Spanish-English individuals in the United States. Practitioners, however, are advised to adapt the proposed principles to the unique backgrounds of other bilingual aphasic clients.


1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.


2016 ◽  
pp. 59-70
Author(s):  
Ninh Le Khuong ◽  
Nghiem Le Tan ◽  
Tho Huynh Huu

This paper aims to detect the impact of firm managers’ risk attitude on the relationship between the degree of output market uncertainty and firm investment. The findings show that there is a negative relationship between these two aspects for risk-averse managers while there is a positive relationship for risk-loving ones, since they have different utility functions. Based on the findings, this paper proposes recommendations for firm managers to take into account when making investment decisions and long-term business strategies as well.


Author(s):  
Mauricio Drelichman ◽  
Hans-Joachim Voth

This epilogue argues that Castile was solvent throughout Philip II's reign. A complex web of contractual obligations designed to ensure repayment governed the relationship between the king and his bankers. The same contracts allowed great flexibility for both the Crown and bankers when liquidity was tight. The risk of potential defaults was not a surprise; their likelihood was priced into the loan contracts. As a consequence, virtually every banking family turned a profit over the long term, while the king benefited from their services to run the largest empire that had yet existed. The epilogue then looks at the economic history version of Spain's Black Legend. The economic history version of the Black Legend emerged from a combination of two narratives: a rich historical tradition analyzing the decline of Spain as an economic and military power from the seventeenth century onward, combined with new institutional analysis highlighting the unconstrained power of the monarch.


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