scholarly journals Chondrocytes isolation from hyaline cartilage by continuous monitoring method

2021 ◽  
Vol 64 (6) ◽  
pp. 13-19
Author(s):  
Vitalie Cobzac ◽  
◽  
Liliana Verestiuc ◽  
Mariana Jian ◽  
Viorel Nacu ◽  
...  

Background: Articular cartilage has poor regenerative capacities. Numerous cartilage repair techniques are known, including implantation of autologous chondrocytes. Material and methods: From 18 rabbits pieces of cartilage were harvested from femoral condyle. Minced cartilage was treated with 0.25% trypsin-EDTA. In the 1st group (n=9) the cartilage was digested with 0.6% collagenase in 15 ml tubes by shaking in incubator at 37°C, 5%CO2 . In the 2nd group (n=9) digestion was performed in 25cm2 cell culture flasks placed on the lateral side, monitoring the process under a microscope after 120 minutes. The isolated cells were cultured to a 80-90% confluence. The chondrocytes were identified using histochemical staining after culturing for 16 days in overconfluence. Results: Chondrocytes isolation in the 1st group lasted a fixed 360 minutes, in the 2nd group – 140±10 minutes. In the 1stgroup were isolated 9.2x104 ±3.1x104 chondrocytes with a viability of 85.36±16.41%, but in the 2nd group – 1.6x105 ±3.4x104 chondrocytes with a viability of 98.09±3.85%. The mean period of cell culture in the 1st group was 15±2 days, in the 2nd group – 11±3 days. In first passage of the 1st group were obtained – 1.2x106 ±4.3x105 chondrocytes and in the 2nd group – 2.92x106 ±3.6x105 chondrocytes. The secreted extracellular matrix by chondrocytes was stained specifically for cartilaginous tissue. Conclusions: The method used for chondrocytes isolation has a direct impact on the number of isolated cells, their viability, but also upon the culture period and the number of cells obtained during the first passage.

1980 ◽  
Vol 45 (3) ◽  
pp. 777-782 ◽  
Author(s):  
Milan Šolc

The establishment of chemical equilibrium in a system with a reversible first order reaction is characterized in terms of the distribution of first passage times for the state of exact chemical equilibrium. The mean first passage time of this state is a linear function of the logarithm of the total number of particles in the system. The equilibrium fluctuations of composition in the system are characterized by the distribution of the recurrence times for the state of exact chemical equilibrium. The mean recurrence time is inversely proportional to the square root of the total number of particles in the system.


2006 ◽  
Vol 10 (4) ◽  
pp. 380-386 ◽  
Author(s):  
Jun Niwayama ◽  
Takashi Sato ◽  
Mizuki Komatsu ◽  
Tsutomu Sanaka ◽  
Takeshi Kurosawa

2017 ◽  
Vol 22 (01) ◽  
pp. 23-28 ◽  
Author(s):  
Mark Henry

Background: Nonunion involving the metaphyseal region of the distal radius is exceedingly rare, usually involving co-morbidity. Patients that have failed multiple prior conventional surgical interventions represent an even more difficult subset to treat; this investigation examined the utility of a specially designed free vascularized medial femoral condyle flap consisting of a central structural block graft with an extended corticoperiosteal sleeve to wrap around the junctions. Methods: Six patients (5 males, 1 female) with a mean age of 52 years had failed to achieve union involving the distal radius metaphysis after a mean of 3.7 prior surgeries occurring over a mean period of 24 months. Comorbidities included smoking, alcoholism, chronic nutritional deficiency, and prior osteomyelitis. The unique descending genicular artery medial femoral condyle flap designed to address these patients consisted of a central structural block graft in continuity with an extended corticoperiosteal sleeve. The structural block filled the bone defect, and the corticoperiosteal sleeve wrapped around the bone junctions and the neighboring bone margins. The mean flap size was 5.3 (+/- 1.3) cm long by 4.5 (+/- 0.9) cm wide. Pre-operative to post-operative DASH scores were compared using the paired student’ s t-test, with p < 0.05. Results: All flaps achieved union at a mean of 6.8 (+/- 2.1) weeks following surgery, using the criteria of bridging trabeculae on all 3 radiographs: coronal, sagittal, and oblique. The mean pre-operative DASH score of 63 (+/- 10) was statistically significantly different compared to the mean post-operative DASH score of 18 (+/- 8). Conclusions: With few alternative solutions able to address this unique and difficult problem, the structural block of vascularized bone with the extended corticoperiosteal sleeve proved able to achieve a union that had failed multiple previous attempts and able to resist reactivation of infection, in a challenging group of patients with comorbidities.


2017 ◽  
Vol 37 (2) ◽  
pp. 191-198 ◽  
Author(s):  
Shenghong Li ◽  
Yong Huang

In this paper, the mean first-passage time of a delayed tumor cell growth system driven by colored cross-correlated noises is investigated. Based on the Novikov theorem and the method of probability density approximation, the stationary probability density function is obtained. Then applying the fastest descent method, the analytical expression of the mean first-passage time is derived. Finally, effects of different kinds of delays and noise parameters on the mean first-passage time are discussed thoroughly. The results show that the time delay included in the random force, additive noise intensity and multiplicative noise intensity play a positive role in the disappearance of tumor cells. However, the time delay included in the determined force and the correlation time lead to the increase of tumor cells.


2018 ◽  
Vol 6 (7_suppl4) ◽  
pp. 2325967118S0013
Author(s):  
Thomas Rudolf Pfeiffer ◽  
Jeremy M. Burnham ◽  
Ajay C. Kanakamedala ◽  
Jonathan Daniel Hughes ◽  
James J. Irrgang ◽  
...  

Objectives: Bony morphologic characteristics have been demonstrated to increase the risk of anterior cruciate ligament (ACL) injury. While posterior femoral condyle condylar offset is an aspect of distal femoral bony morphology that has been reported to influence range of motion and other aspects of knee joint kinematics, it remains unclear whether this characteristic influences the risk of ACL injury. The purpose of the study was to examine the relationship between distal femoral morphology and risks of ACL injury, reconstruction failure, and contralateral ACL injury. It was hypothesized that increased posterior femoral condylar depth, quantified as the cam ratio, would correlate with increased risk of primary ACL injuries, ACL reconstruction failures, and contralateral ACL injuries. Methods: Consecutive patients undergoing evaluation for knee complaints at an academic medical center from 2012-2016 with minimum 24-month follow-up were retrospectively reviewed. Subjects were stratified into four groups: a control group consisting of patients with no ACL injuries and three groups of patients with a primary ACL injury, failed ACL reconstruction, or previous ACL injury with subsequent contralateral ACL injury. Using lateral radiographs, the ratio of posterior condylar depth over total condylar distance was defined as the cam ratio. Analysis-of-variance (ANOVA) and post-hoc testing were used to test for differences in the mean tomahawk ratio between study groups (p<0.05). Receiver Operating Characteristic (ROC) analysis was performed to determine the optimal cam ratio cut-off for detecting increased risk for ACL injury. Results: One hundred and seventy-five patients met inclusion criteria. The mean cam ratios in the control, primary ACL injury, failed ACL reconstruction, and contralateral ACL injury groups were 61.1% (± 2.1), 64.2% (± 3.8), 64.4% (± 3.6), and 66.9% (± 4.0), respectively. Patients with a primary ACL injury, failed ACL reconstruction, or contralateral ACL injury had a significantly higher cam ratio compared to the control group (p<0.008). ROC analysis demonstrated a cam ratio of 63% or greater to be associated with an increased risk for ACL injury with a sensitivity of83% and a specificity of 71%. Conclusion: The data from this study show that an increased posterior femoral condylar depth, or cam ratio, might be associated with increased risk of ACL injury, including primary ACL injury, failed ACL reconstruction, and contralateral ACL injury. The data from this study may help clinicians identify patients at greater risk of ACL injury and re-injury. Future prospective studies will be helpful in investigating the mechanism by which an increased cam ratio increases ACL injury risk and potential strategies to mitigate the increased risk posed by this bony characteristic.


Author(s):  
Hasan Ghobadi ◽  
Shahram Habibzadeh ◽  
Bita Shahbazzadegan ◽  
Mohsen Mirzanezhadasl ◽  
Mahsa Kamranimoghaddam

Background: ICU is the costly part of the hospital that has functional approach for patients who have reversible conditions so it needs mechanical ventilation and other special services. Some patients are not really in need of special care only the continuous monitoring of vital signs needs of the public sector. Patients with good condition or End-Stage were not candidate to admitting in ICU. The aim of this study was to evaluate indications of admitting patients in internal ICU and the rate of mortality in Emam Khomeini hospital in 2013.Methods: The study was conducted retrospectively evaluated the records of patients hospitalized in ICU and disease prognosis and treatment of disease and APACHE2 criteria was analyses.Results: The mean age of patients in the study was 61.05±19.81. Of 118 patients, 70 (59.3%) survived and 48 (40.7%) patients died. APACHE2 mean in the study was 21.46±7.5. GCS average was 9.83±4.27. There was correlation between mortality of patients and type of disease. In this study in APACHE2 score between 25-29 and >35 in mortality rate we are higher than standard average and in 10-14 and 20-24 we are lower than standard average.Conclusions: This study shows that GCS is not a good measure for the evaluation of patients hospitalized in internal ICU. In the present study, patients with higher APACHE2 score of 35 died. That show hospitalization that patient in ICU has no difference in the prognosis of them. As regards mortality rate in ICU patients in this study has no significant difference with predicted APACHE values, indications of ICU admition in Emam Khomeini hospital observed exactly.


2019 ◽  
Author(s):  
Vishal Singh ◽  
Parbati Biswas

Protein aggregation is investigated theoretically via protein turnover, misfolding, aggregation and degradation. The Mean First Passage Time (MFPT) of aggregation is evaluated within the framework of Chemical Master Equation (CME) and pseudo first order kinetics with appropriate boundary conditions. The rate constants of aggregation of different proteins are calculated from the inverse MFPT, which show an excellent match with the experimentally reported rate constants and those extracted from the ThT/ThS fluorescence data. Protein aggregation is found to be practically independent of the number of contacts and the critical number of misfolded contacts. The age of appearance of aggregation-related diseases is obtained from the survival probability and the MFPT results, which matches with those reported in the literature. The calculated survival probability is in good agreement with the only available clinical data for Parkinson’s disease.<br>


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