Relationship between the Depth of Acetabuloplasty and Outcomes of Hip Arthroscopy in Patients with Global Pincer Femoroacetabular Impingement: Study with a Minimum Follow-Up Period of 2 Years.

OBJECTIVE: There has been no definite consensus on the ideal depth of acetabuloplasty, especially in cases of global pincer femoroacetabular impingement (FAI). This study aims to determine whether the depth of acetabuloplasty influences postoperative outcomes in cases of global pincer FAI. METHODS: Data were retrospectively collected from patients with global pincer FAI who underwent hip arthroscopy with a minimum follow-up period of 2 years from May 2014 to December 2018. Patients with global pincer FAI were subdivided into low or high resection depth groups based on whether the intraoperative acetabular rim was resected by more than 3 mm. Radiographic measurements; arthroscopic procedures; preoperative and postoperative PROs were recorded. Achievement of MCID and PASS was compared for the VAS, mHHS, HOS-ADL, and iHOT-12. A paired Student t-test was used to evaluate the significance of preoperative and postoperative PROs and two-tailed unpaired Student t-test was used to compare demographic data and PROs between different groups. MCID and PASS were evaluated using the chi-square test or the Fisher's exact test. RESULTS: A total of 41 hips with global pincer FAI (15 and 26 patients in low or high resection depth groups, respectively) were included in this study. Both groups showed significant postoperative improvements in the scores of all PROs (p < 0.001). Compared to the low resection depth group, the high resection depth group had a lower degree of improvement through hip arthroscopy, which manifested as lower postoperative mHHS scores (94.29 vs. 85.08, p = 0.006), higher VAS scores (0.93 vs. 2.54, p = 0.002), and lower improvements in VAS (-5.00 vs. -3.35, p = 0.028), HOS-ADL (34.99 vs. 23.90, p = 0.017) and iHOT-12 (39.89 vs. 29.27, p = 0.036). Patients in high resection depth group were less likely to achieve the MCID for the VAS score compared to low resection depth group in significant (73.3 vs. 26.9%, p = 0.004). CONCLUSIONS: For patients with global pincer, the outcomes in high resection depth group were slightly worse than the the low resection depth group. It is indicated that excessive resection of the acetabular rim during the procedure should be avoided.

Outcomes in Patients with Global Pincer Versus Focal Pincer Femoroacetabular Impingement Treated with Hip Arthroscopy: A Retrospective Study with a Minimum 2-Year Follow-Up.

OBJECTIVE: Global pincer is a relatively rare form of pincer deformity and is typically associated with technical challenges during surgery. So far, controversy remains whether patients with global pincer have equivalent surgical outcomes compared to patients with focal pincer. This study compares the clinical outcomes of arthroscopic treatment between patients with global pincer femoroacetabular impingement (FAI) and focal pincer FAI in the Chinese population. METHODS: Data were retrospectively collected from patients with global and focal pincer FAI who underwent hip arthroscopy with a minimum two-year follow-up between April 2016 and December 2018. Radiographic measurements, arthroscopic procedures, preoperative and postoperative patient-reported outcomes (PROs) including modified Harris hip score (mHHS), hip outcome score-activities of daily living (HOS-ADL), international hip outcome tool-12 (iHOT-12), and visual analogue scale (VAS) scores, rates of revision surgery and conversion to total hip arthroplasty (THA) were recorded. Achievement of minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) was compared for the VAS, mHHS, HOS-ADL, and iHOT-12 scores between groups. RESULTS: The total of 33 and 167 patients were included in the global and focal group, respectively. There were no intergroup differences in age, gender, body mass index or follow-up times. Lateral center-edge angle (LCEA) was reduced in both groups postoperatively. Both groups demonstrated significant improvements in PROs compared with preoperative levels at the final follow-up. The preoperative scores showed significant differences in terms of mHHS (60.34 vs 62.90, P = 0.031) and HOS-ADL (61.45 vs 64.74, P = 0.022) scores between two groups, and the improvement of HOS-ADL score was significantly higher in global group (P = 0.027). However, the postoperative scores, including VAS, mHHS, HOS-ADL, and iHOT-12 scores, showed no significant differences between two groups. And there were no significant differences in the rate of meeting the PASS and MCID between groups. One (3.0%) in the global group and six (3.6%) patients in the focal group underwent revision arthroscopy respectively, with no significant difference (P = 0.876). There were no conversions to THA in both groups. CONCLUSIONS: Arthroscopic management of global pincer FAI can achieve excellent functional scores at minimum 2-year follow-up. The outcomes were similar to focal pincer FAI patients with a low rate of secondary procedure.

A comparison between ultrasound-guided AIIS injection and radiography in the diagnosis of subspine impingement in patients with FAI.

BACKGROUND: Subspine impingement (SSI) does not have effective diagnostic criteria, especially in patients who also have femoroacetabular impingement (FAI). The classification of anterior inferior iliac spine (AIIS) morphology via three-dimensional CT is controversial. PURPOSE: To propose a method for ultrasound-guided AIIS injection as a way to diagnose SSI and evaluate the accuracy of radiography methods, including 3-D CT and MRI, as well as intraoperative findings. METHODS: Patients diagnosed with FAI between September 2020 and December 2021 were evaluated in this prospective study. Those who met the criteria were included in the ultrasound-guided AIIS injection test. Whether the pain was relieved after injection was recorded in the radiology report. Patients who experienced significant relief of the anterior groin pain (more than 50%) after the AIIS injection were considered positive responders. Among these patients, radiography materials, including AIIS morphology as measured by 3-D CT as well as superior capsular oedema on MRI, were compared. The presence of congestion or bruising on the capsule side of the labrum corresponding to the AIIS during hip arthroscopy was recorded. RESULTS: A total of 73 patients with FAI underwent the ultrasound-guided AIIS injection test. Prevalence rates of 13.70% (10/73), 58.90% (43/73), 23.29% (17/73) and 4.11% (3/73) were recorded for Type I, Type IIA, Type IIB and Type III AIISs, respectively. Thirty-six patients had positive responses to injection, and 37 patients had negative responses to injection. None of the patients with Type I, 23 (53.49%) patients with Type IIA, 11 (64.71%) patients with Type IIB and 2 (66.7%) patients with Type III AIISs had positive responses to the injection. A total of 57.14% of patients with Type II or Type III AIIS had positive responses to the injection. The proportions of patients with superior capsular oedema on MRI in the Type I, Type IIA, Type IIB, and Type III AIIS groups was 0, 30.23, 29.41 and 0%, respectively. Among non-Type I AIIS patients, those who reported positive responses to the injection had a higher incidence of superior capsular oedema (38.89% vs. 14.81%, P = 0.036), but they had no significant differences in the proportion of congestion or bruising of the labrum (47.22% vs. 37.04%, P = 0.419). The results showed that no pairs of methods-ultrasound-guided injection, MRI, and intraoperative findings-achieved good consistency (κ = 0.222, κ = 0.098 and κ = - 0.116). CONCLUSIONS: Radiographic methods including 3-D CT and MRI as well as the intraoperative findings of the labrum cannot be considered an accurate and reliable basis for the diagnosis and treatment of SSI in FAI patients. It is suggested that ultrasound-guided AIIS injections be combined with radiography to better diagnose SSI. LEVEL OF EVIDENCE: IV, case series.

Clinical outcomes of endoscopic synovectomy with adjuvant radiotherapy of pigmented villonodular synovitis of the hip: a case series of single center.

BACKGROUND: Though radiotherapy has been widely used for knee pigmented villonodular synovitis (PVNS), there is few literatures about radiotherapy for the treatment of PVNS hip. Thus, the purpose of this study was to analyze the clinical outcomes of endoscopic synovectomy with/without radiotherapy postoperatively of PVNS hip. METHODS: We performed a retrospective study of patients who underwent endoscopy in our hospital from November 2010 to January 2021. Inclusion criteria was patients with magnetic resonance image (MRI) signs, endoscopic findings and/or histological evidence of PVNS. Exclusion criteria was patients lost follow-up. All patients underwent synovectomy endoscopically and were divided into two groups depending on receiving postoperative radiotherapy or not. The primary outcome measurements were the recurrence of PVNS, receiving revision, and/or converting to total hip arthroplasty (THA). The secondary outcome measurements were the patient-reported outcome (PRO) collected at pre- and post-operation, which consist of Hip Outcome Score Activities of Daily Living (HOS-ADL), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (IHOT-12), Non-arthritic Hip Scale (NAHS), and visual analog scale (VAS). RESULTS: In a case series of 16 patients (8 cases of male, 50%), 4 (25%) cases were localized type and 12 (75%) cases were diffuse type. The average follow-up was 44.8 ± 38.2 months (range,3 to 110). 8 (50%) cases (6 diffuse cases and 2 localized cases) received radiotherapy postoperatively, and the rest (6 diffuse cases and 2 localized cases) received endoscopic treatment alone. At the latest follow-up, 3 (18.75%) cases (2 diffuse cases and 1 localized case) who did not receive radiotherapy converted to arthroplasty. The preoperative HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of remaining 13 patients were 63.1 ± 19.1 (range,32.0 to 98.8), 54.8 ± 20.1 (range, 10.0 to 77.0), 50.9 ± 15.4 (range, 31.0 to 76.6),51.6 ± 15.9 (range, 20.0 to 84.4), 6.0 ± 1.4 (range,4.0 to 8.0) points, respectively. The latest HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of the 13 patients were 79.7 ± 10.8 (range, 58.0 to 97.6), 78.6 ± 9.1 (range,55.0 to 87.0), 74.7 ± 9.7 (range, 55.6 to 91.0), 78.9 ± 18.7 (range,20.0 to 92.5), 3.1 ± 1.2 (range,2.0 to 6.0) points respectively. CONCLUSION: Endoscopic synovectomy can achieve satisfactory PRO in PVNS hip patients. Besides, postoperative adjuvant radiotherapy can achieve higher hip survivability than synovectomy alone in this present study.

The Application of Arthroscopic Techniques in the Diagnosis and Treatment of Hip-Related Conditions in China.

The hip joint is the largest weight-bearing joint in the body and is surrounded by dense capsules and thick muscles. Hip arthroscopic techniques are suitable for the treatment of hip-related conditions. These minimally invasive techniques have rapidly developed in China since 2007. Moreover, they have been used in the treatment of gluteal muscle contracture, snapping hip syndrome, femoral acetabular impingement, acetabular labral injury, hip labral calcification, synovial chondroma, osteoid osteoma, synovitis, osteonecrosis of the femoral head, and developmental dysplasia of the hip. This technique has showed its advantage in the total debridement of lesions, precision treatment, and less trauma. However, we lack understanding of the overall development of arthroscopic techniques in China. This review illustrates the recent development of hip arthroscopic techniques in China and related research progress.

Heterotopic ossification after arthroscopy for hip impingement syndrome.

BACKGROUND: Heterotopic ossification (HO) is a known complication of hip arthroscopy. We investigated incidence of HO after hip arthroscopy and determined whether revision for HO improved outcome. METHODS: A retrospective study was conducted on 242 patients (140 men and 102 women, mean age: 36.2 ±â€Š9.5 years) who underwent hip arthroscopy for femoroacetabular impingement (FAI) between January 2016 and January 2018. The average follow-up period was 22.88 ±â€Š11.74 months (range: 11-34 months). Thirteen (5.37%) cases of HO (six men and seven women, five left hips and eight right hips; mean age: 37.5 ±â€Š4.7 years) were observed. Among them, four cases with HO with obvious pain symptoms and persistent non-remission underwent revision surgery to remove HO. Monthly follow-up was conducted. Visual analog scale (VAS), modified Harris Hip Score (mHHS), and non-Arthritis Hip Score (NAHS) were evaluated and compared between HO and non-HO patients. Independent sample t test, Mann-Whitney U test and the Chi-square test were used for inter-group comparisons. HO degree was evaluated using Brooker classification. Symptoms and function were evaluated before and after revision. RESULTS: A total of 242 patients were involved in this study. Thirteen cases (5.4%) had imaging evidence of HO. Nine (9/13) were classified as Brooker stage I, three (3/13) Brooker stage II, and one (1/13) Brooker stage III. HO was detected by ultrasonography as early as 3 weeks after operation. After primary surgery, the mHHS of the HO group and non-HO group increased by 13.00 (8.50, 25.50) and 24.00 (14.00, 34.50) points (Z = -1.80, P = 0.08), NAHS increased by 18.00 (9.50, 31.50) and 26.00 (13.50, 36.00) points (Z = -1.34, P = 0.18), and VAS decreased by 3.00 (2.00, 4.00) and 4.00 (3.00, 4.50) points (Z = -1.55, P = 0.12). Average follow-up time after revision was 9.00 ±â€Š2.94 months; mHHS increased by 34.75 points (t = -55.23, P < 0.01) and NAHS by 28.75 points (t = -6.03, P < 0.01), and VAS decreased by 4 points (t = 9.80, P < 0.01). HO and non-HO patients were similar for demographic and surgical data, and clinical and functional scores. CONCLUSION: HO incidence after arthroscopic treatment of FAI is similar to that found in previous studies. Most HO have no effect on clinical symptoms. Patients who undergo revision HO resection show improvement in pain and joint function.

Single-nucleotide Polymorphism rs2275294 in ZNF512B is not Associated with Susceptibility to Amyotrophic Lateral Sclerosis in a Large Chinese Cohort.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that primarily affects motor neurons and has no effective treatment. Recently, Iida et al. identified a single-nucleotide polymorphism (SNP) rs2275294 in the ZNF512B gene that is significantly associated with susceptibility to ALS in the Japanese population. Here, we performed a case-control study examining the possible association of rs2275294 with risk of sporadic ALS (SALS) in a large Chinese cohort. METHODS: To assess this association, we performed a replication study in 953 SALS patients and 1039 age- and gender-matched healthy control subjects, who were recruited from Peking University Third Hospital and the First Affiliated Hospital of Anhui Medical University from January 2004 to December 2013 throughout China. We genotyped the rs2275294 SNP using polymerase chain reaction and direct sequencing. RESULTS: The allele frequency of rs2275294 in ZNF512B was different between Japanese and Chinese. The association in Chinese between ALS patients and controls did not reach statistical significance (P = 0.54; odds ratio = 0.94; 95% confidence interval = 0.76-1.15). CONCLUSIONS: The SNP rs2275294 in ZNF512B is not considered to be associated with ALS susceptibility in the Chinese population. Our study highlights genetic heterogeneity in ALS susceptibility in different population. Given our negative results, further replication study involving larger and more homogeneous samples in different ethnicities should be performed in the future.

Protective effect of sinomenine on cartilage degradation and chondrocytes apoptosis.

Sinomenine (SIN), an alkaloid extracted from the stem of the Chinese medicinal plant sinomenium acutum, has been used for treating rheumatoid arthritis. But little is known whether SIN has a protective effect on osteoarthritis (OA). In this study, we investigated the protective effect of SIN on IL-1beta-induced proteoglycan degradation and apoptosis in rabbit articular cartilage and chondrocytes. Treatment with 10 ng/ml IL-1beta increased the level of glycosaminoglycan (GAG) released into the culture media, and up-regulated the activity and mRNA expression of matrix metalloproteinase 13 (MMP-13) and down-regulated the activity and mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in cartilage explants, as confirmed by the methods of GAG quantitation, MMP-13/TIMP-1 enzyme-linked immunosorbent assay (ELISA) and real-time quantitative RT-PCR. Treatment with 10 ng/ml IL-1beta resulted in marked apoptosis in chondrocytes, as demonstrated by decreased cell viability, occurrence of DNA laddering and increased caspase-3 activity and annexin V binding of phosphatidylserine. However, simultaneous treatment with SIN (10, 50 or 250 microM) inhibited the GAG release and the activity and mRNA expression of MMP-13, and enhanced the activity and mRNA expression of TIMP-1 in a dose-dependent manner in cartilage explants. Furthermore, DNA fragment, caspase-3 activity and apoptosis rate were down-regulated, and cell viability was up-regulated dose-dependently in chondrocytes. Thus, SIN has the protective capacity to antagonize cartilage degradation and chondrocyte apoptosis, which suggest that SIN may act as an agent for pharmacological intervention in the progress of OA.

The protective effect of tetramethylpyrazine on cartilage explants and chondrocytes.

AIMS OF STUDY: Ligusticum wallichi Franchat (chuanxiong) is a very common traditional Chinese herbal medicine in China. Tetramethylpyrazine (TMP) is a major active ingredient extracted from Ligusticum wallichi Franchat. We investigated the protective effect of TMP on interleukin-1ß (IL-1ß) induced proteoglycan (PG) degradation and apoptosis in rabbit articular cartilage and chondrocytes. MATERIALS AND METHODS: Rabbit articular cartilage explants and chondrocytes were cultured with 10 ng/ml IL-1ß for 72 h in the absence or presence of various concentrations of TMP (50, 100 or 200 µM). Cartilage and chondroprotective effects of TMP were determined by evaluating (1) the degree of PG degradation by measuring the amount of glycosaminoglycan (GAG) released into the culture media with 1,9-dimethylmethylene blue (DMMB) assay in cartilage explants; (2) gene expression of MMP-3 and TIMP-1 by real-time quantitative reverse transcription-polymerase chain reaction analysis in cartilage explants; (3) chondrocytes viability with MTT assay; (4) the production of intracellular reactive oxygen species (ROS) with laser scanning confocal microscopy (LSCM). Anti-apoptotic effects of TMP were determined by measuring (1) apoptosis with flow cytometric analysis; (2) mitochondrial membrane potential assay with LSCM; (3) caspase-3 activity with special assay kit. RESULTS: IL-1ß treatment increased the level of GAG released into the culture media, and induced the gene expression of MMP-3 and inhibited the gene expression of TIMP-1 in cartilage explants. Moreover, IL-1ß treatment decreased the cell viability and mitochondrial membrane potential, and enhanced the level of intracellular ROS, apoptosis rate, and caspase-3 activity in chondrocytes. However, simultaneous treatment with TMP attenuated the IL-1ß-induced cartilage and chondrocyte destruction in a dose-dependent manner. TMP showed the decrease of GAG degradation and MMP-3 mRNA production, and the enhancement of TIMP-1 mRNA production in cartilage explants. TMP also increased the cell viability in chondrocytes. Furthermore, TMP inhibited the chondrocytes apoptosis through suppression of ROS production, maintaining of mitochondrial membrane potential and downregulation of caspase-3 activity. CONCLUSION: These results demonstrate that TMP has the cartilage and chondroprotective effect, which suggest that TMP could act as an agent for pharmacological intervention in the progress of OA.

Comparative study on early period of recovery between minimally invasive surgery total knee arthroplasty and minimally invasive surgery-quadriceps sparing total knee arthroplasty in Chinese patients.

BACKGROUND: Different kinds of minimally invasive surgery (MIS) procedures have now been used in total knee arthroplasty (TKA). Compared with traditional TKA procedure with a long skin incision, clinical studies showed MIS procedures had some advantages. Quadriceps sparing (QS) procedures are the most minimally invasive MIS procedure until now. This study was aimed to find the insertion types for Chinese patients' vastus medialis and if the QS procedure had some advantages in patients' early recovery. METHODS: Between February 2006 and May 2007, 120 consecutive patients underwent unilateral primary TKA under general anesthesia, among whom 14 patients were lost to follow-up, the remaining 106 cases were enrolled in this study. Among the 106 cases there were 85 right knees, 21 left knees (15 men and 91 women, with a mean age of 65.1+/-7.4 years); osteoarthritis in 97 patients (91.5%) and rheumatoid arthritis in 9 patients (8.5%). MIS TKA was performed in 49 cases (MIS TKA group), while MIS-QS TKA in 57 cases (MIS-QS TKA group). During the operation, the type I, II and III insertions of the vastus medialis for all patients were recorded. Each knee was rated post-operatively according to the Hospital of Special Surgery (HSS) scoring system. Clinical follow-up was undertaken at 1 week, 2, 6, 12 and 24 weeks. Operating time and complications were recorded. RESULTS: There was no statistically significant difference between the two groups for gender distribution, age, left or right knee incidence, pre-operative diagnosis, incidence of varus or valgus deformity. Of the 106 cases there was 1 (0.9%) case with a type I insertion of the vastus medialis, 4 (3.8%) cases with type II insertions, 101 (95.3%) cases with type III insertions. The HSS scoring was significantly different between the MIS-QS TKA group and MIS TKA group within the first two weeks post operation. From 2 weeks later to 24 weeks, no significant difference was found. The average operating time was (53.3+/-12.4) minutes in the MIS TKA group and (64.1+/-15.1) minutes in the MIS-QS TKA group (P<0.001). In the MIS-QS TKA group, 1 patient had delayed healing of the partial skin incision (1.8%). No other complications were found in either group. CONCLUSIONS: Although most of the Chinese patients had type III insertions of the vastus medialis, the MIS-QS TKA procedure showed less injury to the quadriceps than the standard MIS TKA and this could contribute to the earlier recovery of the patients. But a shorter skin incision and more tension on the skin may also lead to more skin complications.

Tissue engineered cartilage from hTGF beta2 transduced human adipose derived stem cells seeded in PLGA/alginate compound in vitro and in vivo.

Chondrogenic potential of human adipose derived stem cells (hASCs) makes them a possible source of seeding cells for cartilage tissue engineering. We aim to examine the chondrogenic differentiation of human transforming growth factor beta2 (hTGF beta2) transduced hASCs seeded in three-dimensional scaffold in vitro and in vivo. In this study, hASCs were isolated from human subcutaneous adipose tissue and transduced with a replication deficient adenovirus carrying hTGF beta2 (Ad5-hTGF beta2), and then the transduced cells were seeded and cultured in PLGA/alginate compounds. RT-PCR analysis revealed that Ad5-hTGF beta2 transduced hASCs produced aggrecan and collagen type II after 7-day induction in vitro and continued throughout the culture period; this was also demonstrated by the positive staining of Alcian blue and immunohistochemistry for collagen type II. For in vivo study, Ad5-hTGF beta2 transduced hASCs seeded in PLGA/alginate compounds were implanted in subcutaneous pockets of nude mice; after 12 weeks, the implants were harvested and examined by haematoxylin and eosin staining, AB-PAS staining, and immunohistochemical analysis, and the results demonstrated the formation of cartilage tissue. As a control, all these were not observed in the constructs with Ad5-EGFP transduced hASCs. In conclusion, our study demonstrates that adenovirus-mediated hTGF beta2 gene transfer is able to induce the hASCs into chondrogenic lineage both in vitro and in vivo. Ad5-hTGF beta2 transduced hASCs combined with three-dimensional PLGA/alginate compound may be a viable method in treating injuries of cartilage.

Ectopic neocartilage formation from predifferentiated human adipose derived stem cells induced by adenoviral-mediated transfer of hTGF beta2.

Chondrogenic potential of human adipose derived stem cells (hASCs) makes them a possible source of seeding cells for cartilage tissue engineering. In this study, chondrogenic differentiation of hASCs induced by transduction with replication-deficient adenovirus carrying human transforming growth factor beta2 (Ad5-hTGF beta2) was demonstrated by RT-PCR, immunohistochemistry staining, biochemical and western blot analysis. To evaluate if the in vitro differentiated hASCs could keep their chondrocytic phenotype and produce neo-cartilage in vivo, predifferentiated hASCs were seeded in different scaffolds and implanted in subcutaneous pockets on the dorsum of nude mice. After 4 and 12 weeks culture in vivo, specimens were harvested and examined by histological and immunohistochemical analysis, cartilage-like tissue formation was only found in alginate gel and PLGA/alginate compound groups, in PLGA group, fibrous tissues and angiogenesis ingrowth were observed. These findings demonstrated that adenovirus-mediated hTGF beta2 gene transfer could induce hASCs into a chondrogenic lineage in vitro, however, this predifferentiation did not guarantee ectopic cartilage formation in vivo unless appropriate three-dimensional scaffolds were used as the cell carry vehicles.

Neocartilage formation from predifferentiated human adipose derived stem cells in vivo.

AIM: To examine the chondrogenic potential of human adipose derived stem cells (hASC) induced by human transforming growth factor beta2 (hTGF beta2) in vitro, and to investigate if predifferentiated hASC can produce neocartilage in vivo. METHODS: hASC were isolated from subcutaneous adipose tissue and cultured in pellets with the addition of hTGF beta2. Chondrogenic differentiation was assayed by RT-PCR, Western blotting, toluidine blue staining, and immunohistochemistry staining for collagen type II. For the in vivo study, intact induced cell pellets or the released cells embedded in alginate gel with different concentrations were implanted subcutaneously in nude mice. Specimens were harvested at different time points and carried with histological and immunohistochemistry examination to evaluate the cartilage formation. RESULTS: RT-PCR analysis revealed that hASC produced aggrecan and collagen type II after 7 d of induction and continued throughout the culture period. This was also demonstrated by the Western blot analysis, positive staining of toluidine blue, and immunohistochemistry for collagen type II. After reseeding in the monolayer, the cells isolated from the pellets displayed a polygonal morphology compared with the primary spindle shape. hASC were released from the induced cell pellets when embedded in alginate gel (implanted cell concentration=5X10(6) /mL or higher). They produced neocartilage after 12 weeks in vivo culture; however, intact induced cell pellets implanted subcutaneously rapidly lost their differentiated phenotype. CONCLUSION: Chondrogenesis of hASC in vitro can be induced by combining pellet culture and hTGF beta2 treatment. Predifferentiated hASC embedded in alginate gel have the ability of producing neocartilage in vivo.

Protective effect of tubuloside B on TNFalpha-induced apoptosis in neuronal cells.

AIM: To investigate the neuroprotective effect of tubuloside B, one of the phenylethanoids isolated from the stems of Cistanche salsa, on tumor necrosis factor-alpha (TNFalpha)-induced apoptosis in SH-SY5Y neuronal cells. METHODS: Cell viability was analyzed using MTT assay. Apoptotic cells were detected using Hoechst33342 staining, and confirmed by DNA fragmentation and flow cytometric analysis. The activity of caspase-3 was measured with special assay kit. The concentration of free intracellular calcium was determined with the probe Indo-1 by spectrometer. The level of intracellular reactive oxygen species and the potential of mitochondrial membrane were determined by laser scanning confocal microscopy (LSCM) combined with fluorescence probe H2DCFDA or JC-1 respectively. RESULTS: SH-SY5Y cells treated with TNFalpha 100 microg/L for 36 h showed typical morphological changes of apoptosis. DNA ladder could be observed by agarose gel electrophoresis. The highest percentage of apoptotic cells accumulated to 37.5 %. Following 36 h treatment with TNFalpha, accumulation of intracellular ROS and [Ca2+]i and decrease in mitochondrial membrane potential were observed, and caspase-3 activity increased by about five-fold compared with controls. However, pretreatment with tubuloside B (1, 10, or 100 mg/L) for 2 h attenuated the TNFalpha-mediated apoptosis. The antiapoptotic action of tubuloside B was partially dependent on an anti-oxidative stress effects, maintain of mitochondria function, decrease of concentration of free intracellular calcium and inhibition of caspase-3 activity. CONCLUSION: Tubuloside B has the neuroprotective capacity to antagonize TNFalpha-induced apoptosis in SH-SY5Y cells and may be useful in treating some neurodegenerative diseases.

Effect of hydroxyurea and etoposide on transduction of human bone marrow mesenchymal stem and progenitor cell by adeno-associated virus vectors.

AIM: To study the effect of hydroxyurea and etoposide on transduction of human marrow mesenchymal and progenitor stem cells by adeno-associated virus (AAV). METHODS: Isolated human bone marrow mesenchymal stem and progenitor cells (hMSCs) were cultured in DMEM containing 10% FBS or 5% FBS and dexamethasone 1 micromol/L respectively. After being treated with hydroxyurea and etoposide, hMSCs were transduced by AAV-LUC. After two days luciferase activity (relative light unites per second or RLU/s) were tested, which indirectly reflected the relative transduction efficiency of different groups, and virus DNA was isolated by Hirt extraction for Southern hybridization. RESULTS: Transduction luciferase activity and transduction efficiency in cultures treated with hydroxyurea and etoposide were significantly higher than that in control cultures. Dividing cells had about 20-fold higher transduction efficiency compared with control cells. Transduction efficiency in stationary cells was about 50 times higher than that in control cells. Southern analysis showed that hydroxyurea and etoposide enhanced second-strand DNA synthesis by rAAV. CONCLUSION: Hydroxyurea and etoposide could increase transduction efficiency of hMSCs by AAV vectors, and stationary cells were more sensitive to these drugs than dividing cells.

In vitro chondrogenesis of human bone marrow-derived mesenchymal progenitor cells in monolayer culture: activation by transfection with TGF-beta2.

Bone marrow-derived mesenchymal progenitor cells are capable of chondrogenesis, making them a possible source of cells for cartilage tissue engineering. Because of this, we studied the effect of human transforming growth factor beta2 (TGF-beta2) on mesenchymal progenitor cell chondrogenesis in monolayer culture using gene transfection technology. A recombinant pcDNA3.1(+)/TGF-beta2 construct containing a full-length TGF-beta2 from a human placental cDNA library was created through gene cloning and DNA recombination. The construct was then lipofected into mesenchymal progenitor cells isolated from human bone marrow. RT-PCR, Western blotting, and immunohistochemistry analyses were performed to identify the expression of TGF-beta2 and cartilage-associated genes and proteins. The results showed that TGF-beta2 was expressed throughout the culture period. The transfected progenitor cells expressed and produced collagen type II and aggrecan 48 h after transfection, and the expression and synthesis were upregulated after 4 weeks. In contrast, the tested genes and proteins were not detected in non-transfected cells. This shows that transfection of pcDNA3.1(+)/TGF-beta2 into mesenchymal progenitor cells is able to provide transient and persistent expression of cartilage-specific genes and proteins, and suggests that the differentiation of human marrow-derived mesenchymal progenitor cells into chondrocytes in monolayer culture is feasible and may be induced by TGF-beta2.