[Clinical effects of free superficial circumflex iliac artery superficial branch perforator flap combined with full-thickness skin graft far from the flap donor site in repairing the large wounds in extremities]

Objective: To investigate the clinical effects of free superficial circumflex iliac artery (SCIA) superficial branch perforator flap combined with full-thickness skin graft far from the flap donor site in repairing the large wounds in extremities. Methods: The study was a retrospective observational study. From January 2020 to June 2022, 19 patients with large wounds in extremities who met the inclusion criteria were admitted to the First Affiliated Hospital of Bengbu Medical College, including 15 males and 4 females, aged 28-75 years. The debridement, fracture reduction and fixation, tendon, vessel, and nerve repair, and vacuum sealing drainage were performed in the first stage surgery. After debridement in the second stage surgery, the total wound area was 13.0 cm×8.0 cm-34.0 cm×15.0 cm. The tendon and bone exposed wound with area of 9.0 cm×6.0 cm-14.0 cm×7.0 cm was repaired with free SCIA superficial branch perforator flap with area of 10.0 cm×6.5 cm-15.0 cm×8.0 cm. The remaining granulation tissue wound with area of 5.0 cm×3.5 cm-13.0 cm×8.0 cm was repaired with full-thickness skin graft far from the flap donor site with area of 5.0 cm×3.5 cm-13.0 cm×8.0 cm. All the wounds in donor site were sutured. The operation time and amount of bleeding of patients during the surgery were recorded, the survival of flap and skin graft were observed after surgery. During follow-up, the flap and skin graft, scar in the donor site and its effect on donor site function were observed. At the last follow-up, the satisfaction of patients with the efficacy was evaluated by the efficacy satisfaction rating score. Results: The operation time of patients was 2.0-3.5 h. The amount of bleeding of patients during the surgery was 100-320 mL. One patient had ecchymosis and venous crisis in the edge of flap on the second day after surgery, and the flap survived after exploration. The flaps of the other patients survived smoothly. The skin grafts of patients all survived smoothly. Two patients had bloated flaps due to obesity in the later stage, and the expected results were achieved after flap thinning surgery 6 months after operation. During the follow-up of 6 to 24 months, the flaps had good elasticity and soft texture, and the skin grafts had no wear or ulceration; linear scars were left in all the donor sites but their functions were not affected. The patients were all satisfied with the efficacy. Conclusions: Free SCIA superficial perforator flap combined with full-thickness skin graft far from the donor site was used to repair the large wounds in extremities, which was safe, reliable, and less traumatic and short in operation time, and resulted in good postoperative appearance and function in the donor sites and recipient sites.

MicroRNA-421 inhibits caspase-10 expression and promotes breast cancer progression

Breast cancer is one of the most prevalent and fatal diseases around the world. The mechanism of tumorigenesis in breast cancer remains to be clarified. miR-421 plays an oncogenic role in many cancers. Although, the clinical significance of miR-421 in patients with breast cancer is still to be investigated. Caspase-10 is one of the initiator of apoptosis. But the relationship between miR-421 and caspase-10 has not been investigated. In the present study, we found that miR-421 was expressed much higher in breast cancer tissues compared to those in adjacent non-tumor tissues. Furthermore, miR-421 promotes cell proliferation and colony formation in vitro. miR-421 inhibits cell apoptosis probably through restraining caspase-10 expression. Thus, miR-421 might be a potential diagnostic maker and therapeutic target for breast cancer.

New insights into the heterogeneity and functional diversity of human mesenchymal stem cells

Mesenchymal stem cells (MSCs) are being tested in several biological systems and clinical settings with the aim of exploring their therapeutic potentials for a variety of diseases. MSCs are also known to be heterogeneous populations with variable functions. In the context of this multidimensional complexity, a recurrent question is what source or population of MSCs is suitable for specific clinical indications. Here, we reported that the biological features of MSCs varied with the individual donor, the tissue source, the culture condition and the subpopulations. Placental chorionic villi (CV) derived MSCs exhibited superior activities of immunomodulation and pro-angiogenesis compared to MSCs derived from bone marrow (BM), adipose and umbilical cord (UC). We identified a subpopulation of CD106(VCAM-1)+MSCs, which are present richly in placental CV, moderately in BM, and lowly in adipose and UC. The CD106+MSCs possess significantly increased immunomodutory and pro-angiogenic activities compared to CD106-MSCs. Analysis of gene expression and cytokine secretion revealed that CD106+MSCs highly expressed several immnumodulatory and pro-angiogenic cytokines. Our data offer new insights on the identification and selection of suitable source or population of MSCs for clinical applications. Further efforts should be concentrated on standardizing methods which will ultimately allow the validation of MSC products with defined biomarkers as predictive of potency in suitable pre-clinical models and clinical settings.

G-CSF-mobilized peripheral blood mononuclear cells from diabetic patients augment neovascularization in ischemic limbs but with impaired capability

BACKGROUND

Autologous transplantation of mobilized peripheral blood mononuclear cells (M-PBMNCs) is a novel approach to improve critical limb ischemia (CLI) in diabetes. However, endothelial progenitor cells (EPCs) from diabetes are dysfunctional and impaired in ischemia-induced neovascularization.

OBJECTIVE

This study aimed to confirm the compromised efficiency of diabetic M-PBMNCs in therapeutic neovascularization, and to determine the underlying mechanisms of this impairment.

METHODS

Diabetic M-PBMNCs from 17 diabetic patients or healthy controls, or phosphate-buffered saline (PBS) were injected into the ischemic limbs of streptozotocin-induced diabetic nude mice. The limb blood perfusion, ambulatory score, ischemia damage, capillary/fiber ratio, arteriole density, collateral vessel formation, and pericytes recruitment were evaluated between these three groups. Non-invasive real time image and histopathology were used to detect the in vivo role of transplanted M-PBMNCs. Proliferation and adhesion of EPCs were assayed. In vitro vascular network incorporation and matrigel plug assay were used to test the pro-neovascularization role of M-PBMNCs.

RESULTS

Transplantation of diabetic M-PBMNCs also improved neovascularization, but to a lesser extent from that observed with non-diabetic ones. This was associated with the impairment of diabetic M-PBMNCs capacity to differentiate into EPCs, to incorporate into vessel-like tubules in vitro, to participate in vascular-like structure formation in a subcutaneous matrigel plug, and to stimulate the recruitment of pericytes/smooth muscle cells. In addition, there was impairment in vasculogenesis, which was related to the reduced adhesion ability of EPCs from diabetic M-PBMNCs.

CONCLUSIONS

Diabetes reduced the capacity of M-PBMNCs to augment neovascularization in ischemia.

Genetic changes induced in human cells in Space Shuttle experiment (STS-95)

BACKGROUND

Results of past space experiments suggest that the biological effect of space radiation could be enhanced under microgravity. To assess the radiation risk for humans during long-term spaceflight, it is very important to clarify whether human cells exhibit a synergistic effect of radiation and microgravity.

HYPOTHESIS

If significant synergism occurs in human cells, genetic changes induced during spaceflight may be detected by using human tumor HCT-116 cells which are hypermutable due to a defect in the DNA mismatch repair system.

METHODS

Cultured HCT-116 cells were loaded on the Space Shuttle Discovery (STS-95) and grown during the 9-d mission. After landing, many single-cell clones were isolated, microsatellite repetitive sequences in each clone were amplified by PCR, and mutations in the microsatellite loci were detected as changes in the length of PCR fragments. Mutation frequencies of ouabain-resistant phenotype were also analyzed.

RESULTS

The frequencies of microsatellite mutations as well as ouabain-resistant mutations in the flight sample were similar to those of the ground control samples. Some cells were treated in space with bleomycin which mimics the action of radiation, but the frequencies of microsatellite mutations were not significantly different between the flight and the ground control samples.

CONCLUSION

Under the present flight conditions, neither space radiation (about 20 mSv during this mission) nor microgravity caused excess mutations in human cells.

Molecular identification of functional water channel protein in cultured human nonpigmented ciliary epithelial cells

PURPOSE

Water channel proteins are important pathways for water movements across cell membranes, including those in the ciliary epithelium, which is the major site of aqueous humor secretion. In this study, we aimed to demonstrate the expression of functionally active aquaporin-1 (AQP1) water channels in cultured human ciliary epithelial cells.

METHODS

Poly A(+) RNA was isolated from cell cultures of Simian Virus 40 (SV-40) transformed human nonpigmented ciliary epithelium (NPE) subjected to RT-PCR reaction using primers specific to AQP1. Northern analysis was used to define the expression of AQP1 in NPE cells. Western immunoblotting with polyclonal antibody raised against AQP1 was used to evaluate the AQP1 protein expression in the plasma membranes of human NPE cells. Light scattering method was used to determine the osmotic water permeability in the suspension of NPE cells.

RESULTS

RT-PCR using specific primers for AQP1, Northern analysis and Western immunoblot using AQP1 specific antibody demonstrated the expression of AQP1 in the plasma membranes of NPE cells. Osmotic water permeability (P( f)) measurements confirmed that functional AQP1 water channels are expressed in human NPE cells and the P(f) for these cells was 9.8 x 10( -3) cm/s at 10 degrees C.

CONCLUSIONS

The presence of AQP1 in human NPE cells suggests that it may have a role in the fluid flow across epithelial membranes. In addition, the existence of AQP1 in the human NPE cells provide an excellent in vivo model to study the regulation of aquaporins and their possible role in the aqueous humor secretion.

A genetic effect of altered gravity: mutations induced by simulated hypogravity and hypergravity in microsatellite sequences of human tumor cells

To determine the possible genetic effects of gravity alterations, we analyzed mutation induction in microsatellite sequences of human tumor cells treated with simulated hypogravity provided by a clinostat or hypergravity by a centrifuge. Microsatellite mutations were detected as changes in the size of polymerase chain reaction (PCR)-amplified allelic markers. The frequencies of mutant clones in cultures treated with simulated hypogravity for 24 or 48 h were almost the same as those of controls, but after 72 h of treatment, the mutant frequencies had increased significantly in all three microsatellite loci examined. Significantly higher mutant frequencies were similarly detected in cultures treated for 72 h with a hypergravity condition as low as 18xg, but not detected in 24 or 48 h treated cultures. These findings clearly show that gravity alterations that last for 3 days can induce microsatellite mutations in human cells. A genetic effect of gravity change, therefore, is established for the first time. Moreover, high frequencies of microsatellite mutations were induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) which activates protein kinase C-mediated signal transduction pathways and causes genetic instability. These findings suggest that gravity change induces microsatellite mutations by modulating the pattern of gene expression involved in signal transduction pathways.

Relative biological effectiveness of accelerated heavy ions for induction of morphological transformation in Syrian hamster embryo cells

Syrian hamster embryo cells were used to study the morphological transformation induced by accelerated heavy ions with different linear energy transfer (LET) ranging from 13 to 400 keV/micron. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), then inoculated to culture dishes. Morphologically altered colonies were scored as transformants. Over the LET range examined, the frequency of transformation induced by the heavy ions increased sharply at very low doses no greater than 5 cGy. The relative biological effectiveness (RBE) of the heavy ions relative to X-rays first increased with LET, reached a maximum value of about 7 at 100 keV/micron, then decreased with the further increase of LET. Our findings confirmed that high LET heavy ions are much more effective than X-rays for the induction of in vitro cell transformation.

Assignment of three Chinese xeroderma pigmentosum patients to complementation group C and one to group E

Four Chinese patients with xeroderma pigmentosum (XP), who had different degrees of skin symptoms, were tested for their genetic complementation groups. Skin fibroblasts obtained from the patients were used for complementation analysis done by a cell-fusion technique. Three of the patients belonged to group C and one, who had the mildest cutaneous manifestations, to group E. This is the first report of a group E XP patient in China. Our present findings together with previous reports suggest that group C XP is more common in China, similar to the distribution among Caucasian XP patients but markedly different from the Japanese distribution.

Effect of low dose radiation on intracellular calcium and protein kinase C in lymphocytes

It is first reported in the present paper that whole-body irradiation (WBI) with low dose X-rays could increase intracellular calcium ions ([Ca2+]i) and stimulate protein kinase C (PKC) activity of mouse lymphocytes. Following WBI of male Kunming mice with 75 mGy X-rays at a dose rate of 12.5 mGy/min the mobilization of [Ca2+]i with Con A in CD4+ and CD8+ Cells in the thymus and spleen was potentiated and the amplitude of [Ca2+]i mobilization in thymocytes in response to anti-CD3 monoclonal antibody increased with time from 4 to 24 h following low dose radiation. The PKC activity in the homogenate of spleen was markedly stimulated 12 h after WBI with 75 mGy, reaching its peak value at 24-48 h and coming down to lower than normal on day 7. However, the PKC activity in the separated T lymphocytes reached its peak value at 12 h and that in the B lymphocytes reached its peak value on day 4, both coming down to below control on day 7. The implications of this facilitation of signal transduction in T lymphocytes in the mechanism of immunoenhancement after low dose radiation were discussed.

Changes in lymphocyte reactivity to modulatory factors following low dose ionizing radiation

Catecholamines (CA) and corticosterone (CS) exerted modulatory effect on the proliferative activity of splenic and thymic lymphocytes in response to mitogenic stimulation in vitro. Epinephrine (E) and norepinephrine (NE) potentiated proliferation in concentrations above 1 and 10 nmol/L, respectively, while CS showed a biphasic effect, stimulating proliferation at concentrations below 0.1 nmol/L and suppressing proliferation at concentrations above 10 nmol/L. Combination of CS with E, NE or both in an ineffective concentration of each (0.1 nmol/L) showed stimulatory effect on the proliferative response of both splenic and thymic lymphocytes to Con A. Whole-body irradiation (WBI) of mice with 75 mGy increased the reactivity of splenic and thymic lymphocytes to Con A. It is reported for the first time in the present paper that the proliferative reactivity of splenic and thymic lymphocytes from low dose irradiated mice could be further increased in the presence of suboptimal concentrations of CS and E as well as suboptimal concentrations of phorbol myristate acetate (PMA) and A23187. These findings may have significance in the mechanism of immunologic stimulation after low dose WBI.

[The effects of frequency of mechanical vibration on experimental fracture healing]

Mechanical vibration was performed with 5 different frequencies after radius fracture of 76 rabbits. The vibration effects were evaluate by means of X-ray film and bio-mechanical and pathological examinations. Our results suggests: (1) Vibration promotes the fracture healing in rabbits regardless of the frequency. Both bone strength and speed of fracture healing are better than those of the controls. (2) Bone strength is elevated by 20% approximately 30% by the best stimulation of stress. (3) The best frequencies are 25Hz and 50Hz, second best, 12.5 and 100Hz and then, 200Hz.

[Experimental study of fracture healing promotion with mechanical vibration in rabbits]

Under aseptic operation, a 0.3mm defect each was resected in the middle shaft of both radii in 54 rabbits. One of 4 groups was subjected to vibration along the long axis of right radius in each healing stage. The feature of fracture healing was evaluated with X-ray film, pathological examinations and measurement of maximum resistance to bending force and pressing stress. The authors came to these preliminary results: (1) The vibration (12.5 approximately 200 Hz) promoted fracture healing; (2) A significant acceleration of fracture healing was seen at the vibrated radius in 3 approximately 4 weeks.

Pregnancy interruption with RU 486 in combination with dl-15-methyl-prostaglandin-F2 alpha-methyl ester: the Chinese experience

In a multicenter study taking place in four centers in Beijing (People's Republic of China), pregnancies up to 49 days of amenorrhea (DA) were interrupted with RU 486 (RU 38486, mifepristone, 600 mg orally once), followed 36-60 hours later by administration of dl-15-methyl-PGF 2 alpha-methyl ester (PG05, 1 mg vaginal suppository). One-hundred-and-sixty women were included in the study, three of whom being excluded from efficacy assessment because of non-compliance to the protocol. Complete pregnancy interruption without additional surgical procedure (success) was obtained in 136 women (86.6%, 95% confidence interval: 81.3-91.9%). The success rate was significantly (P = 0.013) higher for pregnancies below (91.3%), than for pregnancies above 42 days of amenorrhea (DA) (76.6%). The time elapsed between RU 486 intake and complete expulsion was 2.8 +/- 1.5 (sd) days (range: 1-12 days). Expulsion took place at the latest 4 days after RU 486 in 125 women (94.7%), and in 107 of these women, it occurred 3.1 +/- 1.7 (sd) hours after PG05 administration. Uterine bleeding occurred in all women after RU 486 intake whatever the outcome of treatment and lasted 11.5 +/- 4.8 (sd) days (range: 3-36 days). It was judged more or much more abundant than usual periods in 6.15% of the women. It led to a slight but significant decrease in hemoglobin as measured eight and 14 days after RU 486 intake. In five women, hemoglobin decreased by 4 g/dl or more, but no patient required a blood transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)