Application of extended trochanter osteotomy wire fixation combined with autologous bone graft in revision of total hip arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of using lengthened trochanteric osteotomy wire fixation combined with autologous bone graft in patients undergoing revision total hip arthroplasty.@*METHODS@#From December 2010 to December 2018, 18 patients underwent revision of total hip arthroplasty with extended trochanteric osteotomy wire fixation and autogenous bone graft, including 8 males and 10 females with an average age of (78.89±3.32) years old ranging from 68 to 82 years. The time from the initial replacement to the revision was 9 to 22 (16.33±2.93) years. The patients were followed up regularly after operation. The healing time of osteotomy, the time of full weight-bearing activity, Harris score of hip joint and complications were recorded.@*RESULTS@#All 18 patients were followed up for 16 to 38 months with an average of (25.78±6.65) months. The incision length was 16 to 21 cm with an average of (18.89±1.32) cm; the operation time was 105 to 128 min with an average of (115.44±6.59) min, the bleeding volume was 240 to 285 ml with an average of (267.44±13.77) ml. The healing time of osteotomy was 12 to 18 weeks with an average of (15.61±1.75) weeks. Harris score of hip joint was (47.11±5.04) before operation, (76.39±3.85) during full weight-bearing activities, and (82.22±2.76) at the final follow-up(P<0.05). During the follow-up period, there were no complications such as limb shortening, infection, poor incision healing, prosthesis loosening and sinking, and periprosthetic fracture.@*CONCLUSION@#In revision total hip arthroplasty, the use of extended trochanteric osteotomy wire fixation combined with autologous bone graft can achieve satisfactory clinical results, but the surgeon needs to make a systematic plan for the pre-revision, intraoperative and postoperative recovery.

Effect of double plate technique combined with autogenous iliac bone graft in the treatment of femoral nonunion after intramedullary nailing / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of double plate combined with iliac bone graft in the treatment of femoral nonunion after intramedullary nailing.@*METHODS@#From December 2008 to December 2017, double plate combined with autogenous iliac bone graft was used to treat femoral nonunion after intramedullary nailing. There were 11 cases, including 10 males and 1 female, aged 35 to 62 years, and the time from fracture to nonunion was 12 to 20 months. According to Judet classification, there were 8 cases of atrophic nonunion and 3 cases of proliferative nonunion. Regular follow-up was conducted after operation to record the fracture healing time, load-bearing activity time and complications, and to observe the repair effect of double plate fixation combined with iliac bone graft on nonunion after femoral shaft fracture operation.@*RESULTS@#All patients were followed up for 12 to 22 months. The operation time was 70 to 130 min and the blood loss was 180 to 350 ml. After operation, 2 cases had knee stiffness, which recovered after passive exercise with CPM machine for 2 weeks;1 case had pain in iliac bone donor area, which was relieved after 3 months. The time of fracture healing was 24 to 40 weeks, and the time of complete weight-bearing activity was 14 to 32 weeks. SF-36 quality of life score at the final follow-up:body pain 70 to 82, activty 70 to 82, social function 72 to 83, the overall health 72 to 82. At the end of the follow-up, there were no complications such as limb shortening, infection, poor wound healing, internal fixation failure (fracture, loosening).@*CONCLUSION@#It is an effective method to treat nonunion of femur after intramedullary nailing by using double plate combined with autogenous iliac bone graft.

Double plating through different approaches for periprosthetic femoral fracture following total knee arthroplasty / 中国骨伤

OBJECTIVE@#To study clinical effects of double plating through different approaches for communicated and obvious osteoporosis periprosthetic femoral fracture following total knee arthroplasty(TKA).@*METHODS@#From July 2010 to June 2017, 21 patients with periprosthetic femoral fracture following TKA were divided into two groups according to operative approach. Fifteen patients in medial and lateral double approaches group, including 5 males and 10 females aged from 63 to 79 years old with an average of (67.2±5.9) years old; 11 patients were type 33-A2 and 4 patients were type 33-A3 according to AO-OTA classification; 12 patients injured by falling down and 3 patients by traffic accident; treated with double plating. Six patients in medial parapatellar approach group, including 3 males and 3 females, aged from 61 to 74 years old with an average of (64.6±6.0) years old; 3 patients were type 33-A2 and 3 patients were type 33-A3 according to AO-OTA classification; 5 patients injured by falling down and 1 patient by traffic accident; treated with double plating. Operative time, blood loss, postoperative drainage, fracture healing time were compared between two groups; HSS score and radiology at 3 and 12 months were compared between two groups.@*RESULTS@#All patients were followed up, and the follow-up time of bilateral approaches group ranged from 12 to 18 months with an average of (14.2±2.6 ) months, while the follow-up time of single approach group ranged from 12 to 16 months with an average of (12.6±2.5) months, and there was no statistical difference between two groups. The operative time and postoperative drainage in bilateral approaches group were (107.2±10.4) min and (213.9±30.4) ml, while in sigle approach group was (95.4±12.8) min and (256.8±34.2) ml, and the differences were significant(0.05). HHS score at 3 and 12 months after operation in bilateral approach were 82.9±5.7 and 84.8±7.1, while in single approach group were 83.6±6.1 and 86.3±6.8; there was no statistical difference in HSS score between two groups(>0.05). According to HSS score at 12 months after operation, 2 cases got excellent results and 13 good in bilateral approaches group; 1 case got excellent result and 4 good and 1 moderate in single approach group; but there was no statistical difference between two groups (χ²=2.625, =0.105). There wase no significant differences in complications between bilateral approaches group(2 cases) and single approach group (1 case)(>0.05).@*CONCLUSIONS@#Double plating technique for communicated and obvious osteoporosis periprosthetic femoral fracture following TKA could obtain good function of knee joint. The medial parapatellar approach has shorter operative time, while the bilateral approaches had less drainage.

Modified Mclaughlin procedure combined with locking plate for posterior shoulder dislocation with fracture / 中国骨伤

OBJECTIVE@#To study clinical effects of modified Mclaughlin procedure combined with locking plate for posterior shoulder dislocation with proximal humeral fracture which area of femoral head injury less than 40%.@*METHODS@#From July 2012 to June 2017, 7 patients with posterior shoulder dislocation were treated, including 5 males and 2 females; aged from 37 to 53 years old. Three patients combined with split of humerus head and 4 patients combined with humerus surgical neck fracture. All patients treated with modified Mclaughlin procedure combined with locking plate. Motion of shoulder joint after operation was observed, postoperative UCLA score was used to evaluate clinical effects.@*RESULTS@#Seven patients were followed up from 10 to 33 months. The motion of anteflexion and up-lift ranged from 130° to 170°, the motion of extorsion ranged from 45° to 75°, the motion of abduction ranged fron 105° to 150°, and the internal rotation was between L₃ to buttock. UCLA score ranged from 29 to 34; and 1 patient reached excellent, and 6 patients good.@*CONCLUSIONS@#The modified Mclaughlin procedure combined with locking plate showed satisfying result for posterior shoulder dislocation combined with fractures. However, the internal rotation of shoulder could be compromised.

Application of greater trochanteric slide osteotomy in total hip arthroplasty for stiff hip / 中国骨伤

<p><b>OBJECTIVE</b>To study the effect of greater trochanteric slide osteotomy(GTSO) in total hip arthroplasty (THA) for the treatment of stiff hip, as well as the potential complications.</p><p><b>METHODS</b>There were 12 cases enrolled in the study from April 2010 to December 2014, including 9 males and 3 females. The mean age was 49.9 years old (ranged, 37 to 62 years old). The clinical result was evaluated according to the Harris evaluation system, and the radiological evaluations included the healing of the osteotomy, the stability of the prosthesis, and occurrence of heterotopic ossification (HA).</p><p><b>RESULTS</b>The mean follow-up period was 17.3 months (ranged, 15 to 22 months). The mean postoperative Harris score was 88.00±6.11, which was significantly higher than the preoperative mean score which was 43.96±8.46(=-18.34,=0.00). All the osteotomy site abtained good healing without prosthesis loosening or HA. There was 1 patient with infection and 1 patient with pain in greater trochanter.</p><p><b>CONCLUSIONS</b>GTSO is an effective exposure technique in THA for stiff hip, and no marked complication associated with the osteotomy is found in the study.</p>

Analysis on the occult blood loss after unicompartment knee arthroplasty / 中国骨伤

<p><b>OBJECTIVE</b>To calculate the volume of occult blood loss after unicompartment knee arthroplasty(UKA), and analyze its influential factors by comparing with total knee arthroplasty.</p><p><b>METHODS</b>A retrospective study of 130 cases from July 2012 to July 2015 were enrolled, of which and 65 cases were UKA, and 65 cases were TKA. In UKA group there were 27 males and 38 females, and the mean age was (62.3±4.3) years old (ranged, 50 to 82 years old). There were 14 cases older than 70 years old, while 51 cases among 50 to 70 years old. The mean Body mass index (BMI) was (23.9±2.6) kg/m²(ranged, 18.3 to 30.1 kg/m²). In TKA group there were 23 males and 42 females, and the mean age was (67.4±4.9) years old (ranged, 57 to 81 years old). There were 34 cases older than 70 years old, while 31 cases among 50 to 70 years old. The mean BMI was (25.6±2.3) kg/m²(ranged, 20.6 to 33.1 kg/m²). Hidden blood loss was calculated according to Gross equation, and the differences between the two groups including different ages and genders were observed subsequently. The differences of red blood cell change between two groups were observed dynamically postoperatively.</p><p><b>RESULTS</b>Postoperative hidden blood loss was (375.25±168.09) ml, HSS score was 87.11±5.39 in UKA group. Hidden blood loss was (898.81±221.47) ml, HSS score was 82.23±3.08 in TKA group. The differences between the two groups were significant. There were no significant differences in ages and genders. There were no significant relationship between hidden blood loss and HSS score or BMI, while the differences of red blood cell change were significant on the second day, the 4th day and the 5th day. There was no allogenic blood transfusion in UKA group, while 3 patients with transfusion in TKA group.</p><p><b>CONCLUSIONS</b>Hidden blood loss is part of total blood loss after UKA, and the volume in UKA is less than that in TKA. It could be compensated by the body and rarely affect the knee function. The hidden blood is not a risk factor of transfusion.</p>

Analysis of the treatment of posterolateral tibial plateau fracture with three different methods / 中国骨伤

<p><b>OBJECTIVE</b>To analyze and compare the efficacy of surgical approaches and fixations of anterolateral approach, lateral approach and posterolateral approach in treating posterolateral tibial plateau fracture.</p><p><b>METHODS</b>A retrospective study of 44 cases from May 2010 to July 2014 were enrolled, of which there were 21 males and 23 females, and the mean age was 42.5 years old (ranged, 26 to 61 years). All the cases were divided into 3 groups according to the surgical approach, group A was anterolateral approach (19 cases), group B was lateral approach (15 cases), group C was posterolateral approach (10 cases). Operative time and bleeding volum were compared and the knee function was observed.</p><p><b>RESULTS</b>The mean operative time of group A was (91.3±10.4) min, and the bleeding volum of which was (175.3±20.3) ml. The mean operative time of group B was(86.6±9.2) min, and the bleeding volum of which was(155.8±18.2) ml. The mean operative time of group C was (109.5±10.8) min, and the bleeding volum of which was(235.9±29.1) ml. There were significant differences in operative time and bleeding volum between group C and the other two groups(<0.05). The mean follow-up time was 14.9 months (ranged, 10 to 35 months), and the HSS score of last follow-up was 89.6±7.5 (group A), 90.2±6.4(group B), 88.9±5.1 (group C). There were no significant differences in groups(>0.05).</p><p><b>CONCLUSIONS</b>The operative time of posterolateral approach was longer than anterolateral approach or lateral approach, as well as the bleeding volum which was higher in posterolateral approach, while no significant difference of the knee function was observed in these 3 different approaches.</p>

Correlation of medial compartmental joint line elevation with femorotibial angle correction and clinical function after unicompartmental arthroplasty / 中国骨伤

<p><b>OBJECTIVE</b>To study the correlation of postoperative femorotibial angle with medial compartmental joint line elevation after unicompartmental arthroplasty(UKA), as well as the correlation of joint line elevation with the clinical function by measuring radiological joint line.</p><p><b>METHODS</b>A retrospective study of 56 patients from July 2012 to August 2015 was performed. The mean body mass index (BMI) was 23.5 (ranged, 18.3 to 30.1). The standing anteroposterior radiographs of these patients were assessed both pre-and post-operatively, and the knee function was evaluated according to HSS grading. The correlation between postoperative femorotibial angle(FTA) and joint line elevation was analyzed as well as the correlation between joint line elevation and the clinical function.</p><p><b>RESULTS</b>The mean medial joint line elevation was (2.2±2.0) mm(ranged, -3.3 to 7.0 mm), and the mean FTA correction was (2.3±3.0)°(ranged, -4.5° to 9.6°). The mean follow-up period was 12.2 months. There was a significant correlation between in joint line elevation and FTA correction(<0.05), while there was no significant correlation between joint line elevation and the clinical function(>0.05).</p><p><b>CONCLUSIONS</b>There was a significant correlation between medial compartmental joint line elevation and FTA correction after UKA, and the proximal tibial osteotomy was critical during the procedure. There was no significant correlation between joint line elevation and the clinical function, which may be related to the design of UKA prosthesis.</p>

Case report: A 10 years follow-up of periprosthetic femoral fracture after total hip arthroplasty in osteopetrosis / 中华创伤杂志(英文版)

Osteopetrosis is an inherited disorder characterized by increased bone density and brittle bone quality. Degenerative changes often occur after the age of 40 in patients with osteopetrosis. Operative intervention is the primary treatment option if the clinical manifestation of secondary osteoarthritis is severe. A 44-year-old male suffering autosomal dominant osteopetrosis and progressive unilateral hip osteoarthritis required a total hip arthroplasty. However, there were several technical challenges associated with this procedure including creating a femoral medullary canal and developing a Vancouver type B2 periprosthetic femoral fracture postoperatively. To afford some experience for the management of similar cases, we here present our technical solutions to these problems.

Distal fixation prosthesis for unstable intertrochanteric fractures in elderly patients: a mid-term follow-up study / 中国骨伤

<p><b>OBJECTIVE</b>To explore mid-term follow up results of distal fixation prosthesis in treating unstable intertrochanteric fractures in elderly patients.</p><p><b>METHODS</b>From May 2008 to March 2014,58 elderly patients with unstable intertrochanteric were treated with distal fixation prosthesis, among them, there were 15 males and 43 females aged from 75 to 87 years old with an average of 83.2 years old. Fracture were classified according to Evans classification, 39 cases were type I c and 19 cases were type I d. Surgical risk was evaluated before operation, 9 patients were performed total hip arthroplasty and 49 patients were performed prosthetic replacement hip joint function of patients with different age period, Evans classificaton, prothesis type, fixation method were evaluated respectively by using Harris score.</p><p><b>RESULTS</b>Fifty-six patients were followed up from 13 to 36 months with an average of 21.6 months. Harris score was 83.51 ± 6.40, 5 cases got excellent results, 38 cases good and 13 cases moderate. Harris score of patients aged from 75 to 80 years old was 88.64 ± 2.35, 81.64 ± 6.40 in patients aged more than 80 years old, and had significant differences between two groups; Harris score in patients with type Evans I c was 83.64 ± 6.53, and 83.11 ± 6.08 in type Evans I d, while there was no significant differences between two groups. There was no obvious meaning in Harris score between patients with tension band (83.63 ± 6.15) and without tension band (82.41 ± 6.57). There was no significant meaning in Harris score between patients with normal distal fixation prosthesis (83.34 ± 6.43) and femoral moment reconstruction distal fixation prosthesis (83.92 ± 6.51). There was 1 patient occurred hip joint dislocation on the operative side and re-dislocation after manual reduction, then received open reduction. Two patients occurred femoral osteolysis without clinical symptoms, and treated conservative treatment.</p><p><b>CONCLUSION</b>Artificial joint replacement for unstable intertrochanteric fractures in elderly patients, hip joint function in patients aged more than 80 years old is worse, while there was no obvious market effect in fracture classification, whether to use tension band and type of distal fixation prosthesis, moreover, proximal femoral osteolysis should be focused on.</p>

Construction of the tissue engineering seed cell (HaCaT-EGF) and analysis of its biological characteristics

OBJECTIVE@#To construct the tissue engineering seed cell (HaCaT cell line) with stable expression of the human epidermal growth factor (EGF), and analyze the changes of its biological characteristics.@*METHODS@#PCDNA3.1-EGF eukaryotic expression vector was transferred into HaCaT cell, and G418 was utilized to select the HaCaT-EGF cell line. Using an inverted microscope, PCR, ELISA method to detect the changes of the cell morphology, the expression of the EGF gene and protein, and the mRNA expression levels of apoptosis related molecule Caspase-3, the cell cycle related protein cyclin D1.@*RESULTS@#The mRNA expression levels of the obtained HaCaT-EGF cell were more than 100 times higher than the level of ordinary HaCaT cell. The colony of the HaCaT-EGF cells was more focused and tight compared to the empty vector transfected HaCaT cells and normal HaCaT cells. The expression levels of apoptotic factor Caspase-3 and cyclin D1 in HaCaT-EGF cell were significantly higher than those in the empty vector HaCaT- pcDNA3.1 cell, and the differences were statistically significant (P0.05).@*CONCLUSIONS@#HaCaT-EGF cell can continuously secrete EGF, and the biological characteristic is stable. It can be used for tissue engineering experiment and is an ideal seed cell for constructing tissue engineered skin.

Biological effects of paracrine from insulin stimulated adipose-derived stem cells (ADSC) on human vascular endothelial cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the biological effects of the paracrine from ADSC after being stimulated by insulin on vascular endothelial cells.</p><p><b>METHODS</b>(1) ADSC was isolated from human adipose tissue and cultured in vitro. The third generation cells were collected and divided into insulin group (I, cultured with serum-free DMEM containing 1 x 10(-7) mol/L insulin) and control group (C, cultured with serum-free DMEM) according to the random number table, with 6 slots in each group. Three days later, ADSC culture medium (ADSC-CM) was collected for determination of levels of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) by ELISA. (2) Human umbilical vein endothelial cells (HUVEC) were cultured to the third generation, and they were cultured with special nutrient solution and divided into ADSC-CM with insulin stimulation group (AI), ADSC-CM without insulin stimulation group (AC), insulin group (I, with same concentration as above), blank control group (BC) according to the random number table. Three days later, proliferation of HUVEC was determined with MTT method (with expression of absorbance value). Another two samples of HUVEC were respectively divided into 4 groups as above for determination of apoptosis rate with Annexin V/FITC double-staining 12 hours after culture, and HUVEC migration with scratch adhesion test at post scratch hour (PSH) 12, 24, 36, 48. Data were processed with t test.</p><p><b>RESULTS</b>(1) Compared with those in C group [(287 +/- 47), (577 +/- 84) pg/mL, respectively], the secretion levels of VEGF and HGF in I group [(643 +/- 64), (930 +/- 68) pg/mL, respectively] were significantly increased (with t value respectively 18.869, 18.475, P values all below 0.05). (2) The absorbance value of HUVEC in AI and AC groups was 0.847 +/- 0.042, 0.798 +/- 0.022, respectively, which were higher than that in I and BC groups [0.665 +/- 0.028 (with t value respectively 4.579, 3.732), 0.674 +/- 0.031 (with t value respectively 3.761, 4.073), P values all below 0.01], and that in AI group was higher than that in AC group (t = 2.576, P < 0.05). The apoptosis rates of HUVEC in AI and AC groups [(5.8 +/- 1.9)%, (9.0 +/- 2.0)%, respectively] were obviously lower as compared with that in I and BC groups [(30.4 +/- 6.0)% (with t value respectively 12.891, 10.417), (31.4 +/- 7.4)% (with t value respectively 11.474, 9.783), P values all below 0.05 ], and that in AC group was higher than that in AI group (t = 8.548, P < 0.05). The distance of migration of HUVEC in AI and AC groups were greater than that in I and BC groups at PSH 36, 48, and that in AI group was greater as compared with that in AC group (with t value respectively 4.076, 4.573, P values all below 0.05).</p><p><b>CONCLUSIONS</b>Paracrine from ADSC after being stimulated by insulin can promote proliferation and migration of HUVEC, and suppress its apoptosis, and it is beneficial for tissue vascularization.</p>

Effect of heat injured keratinocytes supernatant on biological behavior of fibroblasts / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the effect of the supernatant of heat injured keratinocytes (KC) on biological behavior of the dermal fibroblasts (Fb).</p><p><b>METHODS</b>Human dermal Fb were isolated and cultured. A model of heat injured KC (HaCaT) was reproduced in vitro. Supernatant of normal KC and the supernatant of KC culture 12 hours after heat injury were collected and diluted with non-serum DMEM in 1:1 volume ratio to make normal KC conditioned medium (NKCM) and heat injury KC conditioned medium (HKCM) respectively. Fb was respectively treated with non-serum DMEM and 2 kinds of conditioned medium. (1) The proliferation of Fb was detected with MTT method at post culture hour (PCH) 12, 24, 36, 48. (2) The apoptosis of Fb was determined by flow cytometry at PCH 12 (Fb were heat injured in advance; Fb without heat treatment was used as control). (3) At PCH 24, expression of a-SMA in Fb cytoplasm was determined with immunofluorescence method; expression of a-SMA mRNA in Fb was determined with real-time quantified PCR. Data were processed with one-way analysis of variance, and pairwise comparison among groups with LSD-t test.</p><p><b>RESULTS</b>(1) The proliferation of Fb: the absorbance value of Fb cultured with HKCM at PCH 12, 24, 36, 48 was respectively higher than that of Fb cultured with non-serum DMEM (with t value respectively 1.89, 2.35, 2.02, 1.94, and P values all below 0.01). There were significant statistical differences between the absorbance values of Fb cultured with HKCM and those of Fb cultured with NKCM at PCH 12, 24, and 48 (at PCH 12, t = 1.83, P < 0.01; at PCH 24, t = 2.91, P < 0.05; at PCH 48, t = 1.83, P < 0.05). (2) Apoptosis of Fb cultured with HKCM was diminished as compared with that of Fb cultured with NKCM and of Fb without treatment (t = 3.31, P < 0.05; t = 1.47, P < 0.01). (3) The expression of alpha-SMA (red fluorescence) in Fb cultured with non-serum DMEM or NKCM was less as seen under fluorescence scope, and it was obviously increased in Fb cultured with HKCM. (4) The relative expression amount of alpha-SMA mRNA in Fb cultured with HKCM was 1.32 +/- 0.06, which was higher than that both in Fb cultured with NKCM (1.14 +/- 0.07, t = 2.51, P < 0.05) and in Fb cultured with non-serum DMEM (1.00 +/- 0.09, t = 1.77, P < 0.05).</p><p><b>CONCLUSIONS</b>The supernatant of KC 12 hours after heat injury can obviously promote the proliferation of Fb, inhibit its apoptosis and accelerate transdifferentiation of Fb to myofibroblasts.</p>

Expression of recombinant extracellular region of human interleukin-1 receptor type I in Pichia pastoris / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct pPICZalphaA-soluble interleukin-1 receptor type I (sIL-1RI) recombinant expression vector containing the gene fragment encoding the extracellular domain of sIL-1RI for its expression in Pichia pastoris.</p><p><b>METHODS</b>sIL-1RI gene was amplified by RT-PCR and inserted into the yeast expression vector pPICZalphaA by digestion ligation. The recombinant plasmid pPICZalphaA-sIL1RI was transformed into E.coli Stb13, and the positive clones were analyzed by PCR and DNA sequencing. The pPICZalphaA-sIL1RI recombinant plasmid was electroporated into GS115 cells and the transformants were analyzed by PCR. After phenotype identification, the recombinant strains were induced by methanol to express the target protein, which was analyzed by Western blotting of the cell extract and supernatant.</p><p><b>RESULTS</b>The recombinant plasmid pPICZalphaA-sIL-1RI was constructed successfully, and the results of Western blotting showed that yeast induced by methanol expressed a protein of about 39 kD.</p><p><b>CONCLUSION</b>sIL-1RI protein has been successfully expressed in P.pastoris expression system, which provides the basis for further study of sIL-1RI.</p>

Effects of interferon-gamma on the transforming growth factor beta/Smad pathway in keloid-derived fibroblasts / 中华烧伤杂志

<p><b>OBJECTIVE</b>To elucidate the effects of interferon-gamma (IFN-gamma) on the transforming growth factor beta (TGF-beta)/Smad pathway in keloid-derived fibroblasts (KFb), and to investigate the underlying mechanism in the treatment of pathologic scar with IFN-gamma.</p><p><b>METHODS</b>Keloid tissue of 3 patients were obtained, and then KFb were separated and cultured in vitro. KFb from passages 3 to 5 were used for the study. (1) KFb were divided into control group (incubated with serum-free DMEM), TGF-beta(1) group (treated with 10 ng/mL TGF-beta(1)), IFN-gamma group (treated with 100 ng/mL IFN-gamma), and TGF-beta(1)+IFN-gamma group (incubated with 10 ng/mL TGF-beta(1) combined with 100 ng/mL IFN-gamma). The expression level of mRNA and protein of connective tissue growth factor (CTGF), alpha smooth muscle actin (alpha-SMA) protein and expression of alpha-SMA positive KFb were detected by real-time fluorescent quantitation RT-PCR (FQ-RT-PCR), Western blot and immunofluorescence cytochemical staining. (2) Another sample of KFb was obtained and treated with 10 ng/mL IFN-gamma. The expression level of Smad 3 and Smad 7 protein was detected by Western blot before and 1, 2, 4, 6, 8 h post stimulation (PSH). The expression level of Smad 3 and Smad 7 mRNA was assessed by FQ-RT-PCR before stimulation and 30 mins post stimulation and at PSH, 1, 2, 4, 6, 8. (3) Another sample of KFb was obtained and divided into 1, 10 and 100 ng/mL IFN-gamma groups based on the concentration of IFN-gamma, treated for 4 hours; KFb without IFN-gamma treatment was set up as control group. The expression levels of the protein and mRNA of Smad 3 and Smad 7 were measured by FQ-RT-PCR and Western blot.</p><p><b>RESULTS</b>(1) The level of mRNA and protein of CTGF in IFN-gamma group (0.017 +/- 0.009 and 1.198 +/- 0.004) was respectively lower than that in control group (0.024 +/- 0.013 and 1.229 +/- 0.011, P < 0.05). The level of mRNA and protein of CTGF in TGF-beta(1)+IFN-gamma group (0.634 +/- 0.138 and 1.204 +/- 0.010) was respectively lower than that in TGF-beta(1) group (1.331 +/- 0.298 and 1.727 +/- 0.004, P < 0.01). The fluorescence intensity of alpha-SMA positive KFb (0.922 +/- 0.059) and the expression level of alpha-SMA protein (0.3051 +/- 0.0031) in IFN-gamma group decreased significantly than those in control group (1.055 +/- 0.005 and 0.4513 +/- 0.0094, P < 0.01). The fluorescence intensity of alpha-SMA positive KFb (1.129 +/- 0.004) and the expression level of alpha-SMA protein (0.6734 +/- 0.0098) in TGF-beta(1)+IFN-gamma group decreased significantly than those in TGF-beta(1) group (1.270 +/- 0.005 and 1.3842 +/- 0.0024, P < 0.01). (2) The expression level of Smad 3 mRNA and protein at the first time point after IFN-gamma treatment increased temporarily then decreased gradually, and mRNA expression level reached the nadir at PSH 4, it rose gradually later, though it was still lower at PSH 8 than that before treatment (P < 0.01); protein expression level at PSH 8 was significantly lower than that before treatment (P < 0.01). The expression level of Smad 7 mRNA and protein increased gradually to the maximum at PSH 2 and 4 respectively, then decreased but was still higher at PSH 8 than that before treatment (P < 0.05). (3) Compared with those in control group, the expression levels of Smad 3 mRNA and protein in 1, 10 and 100 ng/mL IFN-gamma group were significantly lower, the expression levels of Smad 7 mRNA and protein were significantly higher (P < 0.05 or P < 0.01). The higher concentration of IFN-gamma, the more significant differences were observed.</p><p><b>CONCLUSIONS</b>IFN-gamma can down-regulate the expression of Smad 3 while up-regulate the expression of Smad 7 in a time- and dose-dependent manner, and reduce the expression level of CTGF and alpha-SMA in the basic state or induced by TGF-beta(1), which shows a significant inhibitory effect on the TGF-beta/Smad signal pathway. This may be an important mechanism in the treatment of pathologic scar by IFN-gamma.</p>