The generation of the endothelial specific cdc42-deficient mice and the effect of cdc42 deletion on the angiogenesis and embryonic development / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>High microvascular permeability plays an essential role in pathological process of multiple diseases such as septic shock, acute lung injury and acute respiratory distress syndrome, and burns. Inhibiting hyperpermeability is significant for controlling these conditions. Cdc42, as a main member of the small Rho GTPase family, plays a critical role in controlling and regulating the endothelial junctional permeability. We aimed to generate and identify endothelial specific cdc42-deficient mice by the Cre/loxp recombination approach, for examination in an animal model of the contribution of the cdc42 gene in the microvascular barrier function.</p><p><b>METHODS</b>We crossed cdc42(Flox/Flox) mice with mice expressing endothelial cell-specific Cre recombinase, and the offspring with the genotype cdc42(Flox/+)Tie2Cre(+/-) were back-crossed with the cdc42(Flox/Flox) mice. The cdc42(Flox/Flox)Tie2Cre(+/-) mice in the F2 generation were the target mice. If the cdc42 deficient mice did not survive, we would observe the cdc42 deficient mice embryos, and compare them with wild-type mice embryos.</p><p><b>RESULTS</b>Cdc42(flox/+)Cre(+/-) mice were mated with the cdc42(Flox/Flox) mice and among the living offspring there were no cdc42(Flox/Flox)Cre(+/-) target mice. We found the endothelial special cdc42 deficient embryos at the E7.5-E16.5 stage. We observed that cdc42 deficient embryos were much smaller, had fewer vessels and were a little more swollen compared with the wild-type embryos.</p><p><b>CONCLUSIONS</b>Endothelial specific knockout of cdc42 caused embryonic lethality and the mice did not survive to birth. The target embryos were much smaller, had fewer vessels and were a little more swollen compared with the wild-type embryos. These results demonstrated that the cdc42 plays an important role in development of embryos and in development of microvessels as well as microvascular permeability.</p>

The comparison between the vascular endothelial cells special cdc42-deficient heterozygous mice and the non-knockout mice on lung tissue pathological change and vasopermeability in acute lung injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the change of lung tissue and vasopermeability between the vascular endothelial cells special cdc42-deficient heterozygous mice and the non-knockout mice in acute lung injury.</p><p><b>METHODS</b>The mice with vascular endothelial cell-specific expression of cre recombinase were crossed with cdc42(flox/flox) mice. The cdc42(flox/+)Cre(+/-) F1 offspring mice were crossed back with cdc42(flox/flox) mice, resulting in the F2 generation mice with three genotypes, namely cdc42(flox/+)Cre(+/-), cdc42(flox/flox)Cre(-/-) and cdc42(flox/+)Cre(+/-). The heterozygous mice with cdc42(flox/+)Cre(+/-) genotype were selected as the model mice, with the other two genotype groups as the control. After intratracheal instillation of 2 mg/kg LPS to induce acute lung injury, the mice were sacrificed to examine the lung pathologies, lung wet/dry ratio and lung microvascular permeability.</p><p><b>RESULTS</b>The heterozygous mice with cdc42 gene knockout (cdc42(flox/+)Cre(+/-)) showed no significant differences from the two control groups in the lung pathological score, lung wet/dry ratio or the lung microvascular permeability coefficient.</p><p><b>CONCLUSION</b>There were no significant difference on lung tissue and vasopermeability between the vascular endothelial cells special cdc42-deficient heterozygous mice and the non-knockout mice.</p>

Therapeutic effect of tiotropium bromide powder inhalation in patients with stable bronchiectasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the therapeutic effect of tiotropium bromide powder inhalation on stable bronchiectasis.</p><p><b>METHODS</b>Twenty-two patients with stable bronchiectasis received inhalation of totropium bromide powder at the daily dose of 18 microg, and on days 1 and 28, the patients were examined for forced expiratory volume in one second (FEVl), predicted value [FEVl(%)], forced expiratory volume (FEV), and FEVl/FVC. The symptom score and BODE index were also recorded.</p><p><b>RESULTS</b>After 1 month of inhalation therapy, the FEV1% of the patients showed a moderate increase but the increment was not statistically significant (t=-1.875, P>0.05); the symptom score and BODE index decreased significantly after the therapy (t=7.091, P<0.001; t=2.982, P<0.05).</p><p><b>CONCLUSION</b>Long-term inhalation of tiotropium bromide powder can improve the clinical symptoms and BODE index and enhance the exercise tolerance and quality of life of the patients with bronchiectasis.</p>

Comparison of full-field digital mammography and magnetic resonance imaging for breast disease diagnosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the effectiveness of full-field digital mammography (FFDM) and magnetic resonance imaging (MRI) in the detection and diagnosis of breast diseases.</p><p><b>METHODS</b>Forty-one patients with 47 breast lesions (20 malignant and 27 benign lesions) underwent preoperative FFDM and MRI, using the pulse sequences including T1WI, T2WI, T2WI/SPIR diffusion-weighted imaging (DWl), and 3D dynamic contrast-enhanced MRI.</p><p><b>RESULTS</b>The imaging and pathological findings were compared, and the detection rates of the lesions by FFDM and MRI were 97.87% (46/47) and 74.46% (35/47), respectively (P<0.01). The sensitivity of FFDM and MRI was 70.00% (14/20) and 80.00% (16/20) (P>0.05), with specificity of 62.96%(17/27) and 88.89%(24/27) (P<0.05), respectively.</p><p><b>CONCLUSION</b>MRI is superior to FFDM in the detection and diagnosis of breast diseases.</p>

Expression of the P450arom mRNA in the glandular tissue of the pubertal mammary hypertrophy / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the expression status of the P450arom mRNA in breast tissue of pubertal mammary hypertrophy and then explore the possible etiology of pubertal mammary hypertrophy.</p><p><b>METHODS</b>15 patients were selected for pubertal mammary hypertrophy group. Breast hypertrophy tissue specimens were collected from the gland excised during reduction mammaplasty. 15 patients with pathologically simple fibroadenoma were used as another control group. Patient approval of participation in this study was obtained preoperatively. The expression of P450arom mRNA was detected by RT-PCR in all the cases above.</p><p><b>RESULTS</b>There was no significant difference between the pubertal mammary hypertrophy groups and normal groups on the expression rates of P450arom mRNA. But among the positive cases, the expression of P450arom mRNA within breast tissue were 0.202 +/- 0.048 in pubertal mammary hypertrophy group; and 0.159 +/- 0.068 in normal group. There was significant difference between the pubertal mammary hypertrophy and normal groups (P < 0.05).</p><p><b>CONCLUSION</b>The expression of P450arom mRNA in pubertal mammary hypertrophy are significantly higher than in normal mammary glandular tissue. The pubertal mammary hypertrophy may be related to the expression status of P450arom mRNA within breast tissue.</p>

Biological dressing with human hair keratin-collagen sponge-poly 2-hydroxyethyl methacrylate composite promotes burn wound healing in SD rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a composite material containing human hair keratin (HHK), collagen sponge (inner layer) and poly 2-hydroxyethyl methacrylate (PHEMA) film that allows sustained release of polydatin and test its effect as a biological dressing in promoting burn wound healing in SD rats.</p><p><b>METHODS</b>Three HHK materials with fast, moderate, and low degradation rates were mixed at the ratio of 4:3:3 to prepare a reticular structure, which was processed into a composite material with bovine tendon-derived collagen sponge, and further complexed with HEMA film containing PD prepared by polymerization. Degree II burn wound was induced in SD rats by scalding and within postburn day 2-5, the wounds were cleansed and covered with the composite material or with glutaraldehyde-treated porcine skin (positive control). At week 1, 2, 4, 6 and 8 following wound dressing, 6 full-thickness skin samples were harvested from the wounds for histological observation and immunohistochemical detection of collagen and elastic fibers, and the wound healing time and healing rate were recorded.</p><p><b>RESULTS</b>The prepared collagen sponge film was transparent and porous (50-300 microm in diameter) and allowed sustained PD release into normal saline within 48 h. Compared with the porcine skin, the composite material reduced exudation and maintained ideal moisture of the wound, and significantly shortened the wound healing time (P=0.000). On day 7, 14, and 21 following dressing, the composite material and porcine skin significantly increased the wound healing rate as compared with the negative control group (P=0.000), and on day 14, the composite achieved significantly greater healing rate than the porcine skin (P<0.05).</p><p><b>CONCLUSION</b>HHK-collagen sponge-PHEMA/PD composite as a dressing material promotes burn wound healing in rats by allowing in vivo construction of tissue engineered epidermis. PHEMA is feasible for sustained drug delivery in this composite.</p>

Study on the protective effects of ZnSO4 on rat flaps with ischemia reperfusion injury / 中华整形外科杂志

<p><b>OBJECTIVE</b>To observe the protective role of the ectogenesis zinc in the rat flap with ischemia-reperfusion injury and study the mechanism.</p><p><b>METHODS</b>An abdominal island flap was created in Wistar rats. 48 rats were randomly divided into three groups, 16 per group: the non-ischemia-reperfusion group, the ischemia-reperfusion group and the ischemia-reperfusion (IR) group treated with zinc. The content of malondialdehyde (MDA) and the activity of myeloperoxidase (MPO) were measured. The expression of metallothionein (MT) was observed, and the image analysis was performed. The ultrastructure changes of the skin flap with ischemia-reperfusion injury and the flap viability were observed.</p><p><b>RESULTS</b>Compared with the IR group, at 1 h and 24 h of reperfusion, the level of MDA in the adding-zinc-IR group decreased 11.3% and 33.2% (P < 0.05); the activity of MPO decreased 14.2% and 22.7% (P < 0.05); the content of MT increased 41.5% and 44% ( P < 0.01) respectively. In the ischemia-reperfusion injury flaps, MT was located in the cytoplasm of many kinds of cells. The ultrastructure changes of the skin flap of the adding-zinc-IR group were slighter than those of the IR group. The flap viability in the adding-zinc-IR group increased 27.2% (P < 0.05).</p><p><b>CONCLUSIONS</b>MT could be induced by ectogenesis zinc in the flap of rats. The flap with ischemia-reperfusion injury was protected by MT through protecting the cells in the flap.</p>

Preparation and bioactivity of human hair keratin-collagen sponge, a new type of dermal analogue / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a three-dimensional porous film of human hair keratin (HHK)-collagen sponge complex for use as a dermal substitute.</p><p><b>METHODS</b>The three components F, B, and Z derived from healthy human hair were weaved into a meshwork and integrated with purified soluble type I collagen extracted from bovine tendons to prepare a highly porous film with vacuum freeze-drying followed by secondary cross-linking with glutaraldehyde. The film was grafted beneath the dorsal skin in 21 SD rats (experimental group), with simple collagen sponge serving as the negative control. The rats receiving surgical operation but without graft served as the blank control. The graft and its surrounding tissue were harvested on days 3, 7 and at weeks 2, 4, 6, 8, 12 after implantation for evaluation of tissue compatibility, vascularization and degradation.</p><p><b>RESULTS</b>The prepared collagen sponge film was semitransparent and porous. Three to 7 days after grafting, inflammatory reaction was relieved gradually, and several fibroblasts and blood vessels were found adherent to the grafts in the experimental groups. At week 4, the wounds healed in the experimental groups, and the fibroblasts were actively secreting collagen and the film degraded obviously with the appearance of elastic fibers. At weeks 6 and 8, new collagen fibers thickened and assumed regular arrangement, and the collagen sponge films disappeared completely. In the control groups, the changes were less obvious and total HHK degradation occurred till week 12.</p><p><b>CONCLUSION</b>The degradable and absorbable HHK-collagen sponge film has relatively satisfactory tissue compatibility and can accelerate wound healing by stimulating cell proliferation and vascularization, showing the potential as an optimal dermal substitute.</p>

Effects of serum of the rats ventilated with high tidal volume on endothelial cell permeability and therapeutic effects of ulinastatin / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>With the widespread use of ventilators in treating critically ill patients, the morbidity of ventilator-induced lung injury (VILI) is increasing accordingly. VILI is characterized by a considerable increase in microvascular leakiness and activation of inflammatory processes. In this study we investigated the effects of inflammatory mediators in VILI rat serum on endothelial cytoskeleton and monolayer cellular permeability, as well as the therapeutic effect of ulinastatin, to explore the pathogenesis and the relationship between biotrauma and lung oedema induced by VILI.</p><p><b>METHODS</b>Thirty healthy male Sprague-Dawley rats were randomly divided into three groups: group A (normal tidal volume ventilation), group B (high tidal volume ventilation) and group C (high tidal volume ventilation plus ulinastatin). The serum of each rat after ventilation was added to endothelial cell line ECV-304 medium for two hours to observe the effects of serum and/or ulinastatin on endothelial fibrous actin and permeability.</p><p><b>RESULTS</b>Compared to rats ventilated with normal tidal volume, serum of rats ventilated with high tidal volume caused a striking reorganization of actin cytoskeleton with a weakening of fluorescent intensity at the peripheral filament bands and formation of the long and thick stress fibres in the centre resulting in endothelial contraction and higher permeability. Prior treatment with ulinastatin lessened the above changes significantly. The changes of permeability coefficient of endothelial permeability after group A, B or C rats serum stimulation were (6.95 +/- 1.66)%, (27.50 +/- 7.77)% and (17.71 +/- 4.66)% respectively with statistically significant differences (P < 0.05) among the three groups.</p><p><b>CONCLUSIONS</b>The proinflammatory mediators in the serum of the rats given high tidal volume ventilation increases endothelial permeability by reorganizing actin cytoskeleton, and pretreatment with ulinastatin lessens the permeability by inhibiting of proinflammatory mediators.</p>

Transcatheter arterial chemoembolization in the treatment of hepatocellular carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the effect of transcatheter arterial chemoembolization (TACE) on the result and the prognosis of hepatocellular carcinoma (HCC) at systemic, cellular, genetic and molecular levels.</p><p><b>METHODS</b>Patients with histologically proven HCC were divided into two groups: 81 patients in Group A undergoing TACE before operation and 58 patients in Group B treated with surgical resection alone. The degree of apoptosis was analyzed by transferase -mediated dUTP nick end labeling (TUNEL) stain. The expressions of bcl-2, bax, p53, Ki-67 and PCNA proteins were detected by immunohistochemical method. The changes of these markers, tumor necrosis, encapsulation, volume, metastasis, recurrence and cumulative survival in each group were retrospectively analyzed.</p><p><b>RESULTS</b>The more tumor necrosis, apoptosis, encapsulation and tumor shrinkage observed, and the less recurrence resulted from TACE in group A than in group B. The cumulative 1-, 2-, and 3-year survival rates and median survival time were 84.0%, 67.9%, 40.7%, and 803.3 days in group A patients; they were 72.4%, 55.2%, 24.1%, and 742.5 days in group B patients (P < 0.05).</p><p><b>CONCLUSION</b>Preoperative transcatheter arterial chemoembolization is safe and effective as an auxiliary preparatory means before surgical treatment of hepatocellular carcinoma as it may improve the survival of HCC patients.</p>

Sequence Analysis of 4.0 kb Region Upstream of the Chitinase Gene of Spodoptera litura Nucleopolyhedrovirus / 中国病毒学

The region of about 4.0 kb upstream of Spodoptera litura nucleopolyhedrovirus (SpltNPV) chiA gene was sequenced, in which six open reading frames(ORF1～6) were found. These ORFs are 156, 297, 540, 369, 1281, and 228 nucleotides long, encoding the proteins of 51, 98, 179, 122, 426, and 75 amino acids with the molecular weight of 6.15 kD, 11.46 kD, 21.70 kD, 14.69 kD, 47.59 kD, and 9.09 kD respectively. One early promoter motif CAGT in ORF1 and ORF3, two early promoter motifs CAGT in ORF2, one late promoter motif TAAG in ORF4 and two late promoter motifs TAAG in ORF5 were found in 5′noncoding regions of these ORFs. The polyadenylation signals, AATAAA, are located downstream of the translation stop codon of ORF1, ORF4 and ORF5. ORF4 is the homologous gene of AcMNPV ORF53, BmNPV ORF42, OpMNPV ORF56 and LdMNPV ORF54. Compared with all genes from baculoviruses, ORF1, ORF2 and ORF6 have no homologous genes. It is suggested that ORF1, ORF2 and ORF6 may be three novel baculovirus genes.