Characterization and principal component analysis of functionality-related characteristics of hydroxypropyl methylcellulose type 2208 / 药学学报

Under the guidance of Chinese Pharmacopoeia (2020 edition), the functionality-related characteristics of hydroxypropyl methylcellulose (HPMC) type 2208 from imported A manufacturer, domestic S manufacturer, domestic T manufacturer and different batches of the same manufacturer were characterized. The principal component analysis was used to comprehensively evaluate the functionality-related characteristics. The results were as follows: hydroxypropyl methylcellulose had no significant difference in viscosity and molecular weight distribution between different manufacturers, and there were significant differences in the cumulative particle size distribution of the sample reaches 50% (d50) and 90% (d90), bulk density, tap density and Carr's index. The HPMC from A manufacturer have the biggest inter-batch difference of particle size and their inter-batch difference of polydispersion coefficientis smaller than S manufacturer. Domestic manufactures have the largest inter-batch difference in other functionality-related characteristics. The three principal components were extracted by principal component analysis, and the variance contribution rate reached 89.44%, indicating that the extracted principal components can explain all the data well. By constructing a comprehensive evaluation model, the comprehensive score ranking of all HPMC samples is obtained: S manufacturer > A manufacturer > T manufacturer.

Effect of platelet-derived growth factor-BB on the healing and adhesion of rat tendon / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the effect of platelet-derived growth factor-BB (PDGF-BB) gene transfected rat tendon cells on the healing and adhesion of rat tendon.</p><p><b>METHODS</b>A model of heel tendon injury was reproduced in 90 rats. They were randomly divided into three groups: experiment group [with injection of 20 µL rat tendon cells (1 × 10(8) cell/mL) transfected with PDGF-BB gene into the injured tendon ends], control group [with injection of 20 µL non-transfected rat tendon cells (1 × 10(8) cell/mL) into the injured tendon ends], and blank control group (without treatment), with 30 rats in each group. Heel tendon ends were sutured with 6-0 thread by modified Kessler method and immobilized with tube-type plaster of Paris cast for one week. Rat tendon cells transfected with PDGF-BB gene were identified with gene sequencing and RT-PCR. Tendon tissue sample was harvested 3 days or 1, 2, 4, 8 week(s) after operation (POD or POW) for morphology and histology observation, and bio-mechanical test. The degree of tendon adhesion, the number of Fb and collagen fiber content in tissue, maximum tensile strength and sliding distance of tendon, and concentration of PDGF-BB in tendon tissue among groups were compared. Data were processed with t test.</p><p><b>RESULTS</b>(1) PDGF-BB mRNA expressed stably in PDGF-BB gene transfected tendon cells as testified by RT-PCR and gene sequencing. (2) Obvious edema and inflammatory cells infiltration were observed in each group on POD 3, but they were less pronounced in experiment group. And the changes in all groups were ameliorated gradually. The difference in grading of tendon adhesion was not obvious among groups in POW 4 and 8. (3) Fb number in experiment group in POW 2, 4, 8 was respectively fewer than that of control group and blank control group (with t value respectively 2.94, 4.26, 5.76 and 4.00, 3.83, 6.12, P < 0.05 or P < 0.01). (4) Collagen fiber content in rat tendon of experimental group in POW 4 was (43 ± 6)%, which was significantly lower as compared with that of control group [(55 ± 8)%] and blank control group [(61 ± 8)%] (with t value respectively 2.94 and 4.41, P < 0.05 or P < 0.01). (5) The largest sliding distance of tendon in experiment group in POW 4 and 8 were (3.25 ± 0.33) and (3.65 ± 0.21) mm, which were significantly longer than those in control group [(2.29 ± 0.40), (2.21 ± 0.37) mm] and blank control group [(2.01 ± 0.23), (1.89 ± 0.24) mm] (with t value respectively 4.53, 8.29 and 7.55, 13.52, P values all below 0.01). There was no statistical significant difference among the three groups in the maximum tensile strength of tendon (with t value respectively 0.41, 0.41, 0.77, 0.72, P values all above 0.05). (6) Content of PDGF-BB in tendon tissue of experimental group on POD 3 and in POW 2, 4 were (12.95 ± 1.36), (8.32 ± 0.94), (9.10 ± 1.06) ng/mL, all significantly higher than those in control group [(1.13 ± 0.21), (2.07 ± 0.48), (3.85 ± 0.39) ng/mL] (with t value respectively 21.04, 14.50, 11.39, P values all below 0.01).</p><p><b>CONCLUSIONS</b>PDGF-BB gene transfected rat tendon cells can promote endogenous healing of tendon and prevent tendon adhesion.</p>

Effect of platelet-derived growth factor-BB on proliferation of tendon cells cultured in vitro / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the effect of platelet-derived growth factor-BB (PDGF-BB) in different concentrations on proliferation of tendon cells cultured in vitro.</p><p><b>METHODS</b>Rat tendon cells were cultured and identified in vitro. The rat tendon cells were cultured in PDGF-BB nutrient solution in different concentrations. They were then divided into 1, 5, 10, 20, 50, 100, 150, 200, 250 ng/mL PDGF-BB groups (cultured with 0.1 mL 0.5% PBS with addition of 1, 5, 10, 20, 50, 100, 150, 200, 250 ng/mL PDGF-BB respectively). Tendon cells in control group were cultured with 0.1 mL 0.5% FBS. Proliferation of tendon cells was detected by MTT test. The absorbance values of tendon cells in control group and 20 ng/mL PDGF-BB group before culture and after cultured for 12, 24, 36, 48, 60, 72 hs were determined.</p><p><b>RESULTS</b>The isolated cells were identified to be rat tendon cells as they were Type I collagen staining positive and TypeIII collagen staining negative. Compared with that of control group, the absorbance values of other groups were all increased, except for that of 250 ng/mL PDGF-BB group (P < 0.05 or P < 0.01). Besides, the absorbance value rose gradually with the increase of the concentration of PDGF-BB on, and then diminished gradually with the increase of the concentration of PDGF-BB from 20 ng/mL on. Tendon cells in 20 ng/ml PDGF-BB group began to increase in number when cultured for 12 hs, and it reached the highest level (0.53 +/- 0.04) at 48 h, which were obviously higher than those of control group at 24 - 72 h (P < 0.01). The absorbance value of tendon cells in 20 ng/mL PDGF-BB group was significantly higher than that of control group at 24, 36, 48, 60, 72 h after culture (P < 0.01).</p><p><b>CONCLUSIONS</b>PDGF-BB can promote the proliferation of tendon cells in a definite range of concentration and time.</p>