Mesenchymal Stem Cells in Acquired Aplastic Anemia: The Spectrum from Basic to Clinical Utility.

Aplastic anemia (AA), a rare but potentially life-threatening disease, is a paradigm of bone marrow failure syndromes characterized by pancytopenia in the peripheral blood and hypocellularity in the bone marrow. The pathophysiology of acquired idiopathic AA is quite complex. Mesenchymal stem cells (MSCs), an important component of the bone marrow, are crucial in providing the specialized microenvironment for hematopoiesis. MSC dysfunction may result in an insufficient bone marrow and may be associated with the development of AA. In this comprehensive review, we summarized the current understanding about the involvement of MSCs in the pathogenesis of acquired idiopathic AA, along with the clinical application of MSCs for patients with the disease. The pathophysiology of AA, the major properties of MSCs, and results of MSC therapy in preclinical animal models of AA are also described. Several important issues regarding the clinical use of MSCs are discussed finally. With evolving knowledge from basic studies and clinical applications, we anticipate that more patients with the disease can benefit from the therapeutic effects of MSCs in the near future.

Minimally invasive surfactant therapy versus intubation for surfactant administration in very low birth weight infants with respiratory distress syndrome.

BACKGROUND: Minimally invasive surfactant therapy (MIST) is a new mode of surfactant administration without intubation to spontaneously breathing preterm infants with respiratory distress syndrome (RDS). The aims of this study were to assess the feasibility, efficacy and safety of using MIST to give surfactant for very low birth weight (VLBW) infants with RDS. METHODS: In total, 53 VLBW infants who were born before 32 gestational weeks with spontaneous breathing, respiratory distress, and requiring surfactant therapy were divided into two groups. The infants in group A (n = 29) were intubated and received surfactant replacement therapy via endotracheal tube, followed by mechanical ventilation (MV). The infants in group B (n = 24) received tracheal instillation of surfactant via a semirigid vascular catheter during spontaneous breathing under nasal continuous positive airway pressure (nCPAP). After surfactant instillation, the infants in group B were still placed on nCPAP. RESULTS: Our data showed that infants in group B (MIST group) had significantly lower rate (P < 0.05) of composite outcome of death or bronchopulmonary dysplasia (BPD), duration of intermittent positive airway pressure ventilation (IPPV) or MV, drug treatment of patent ductus arteriosus (PDA), and surgical ligation of PDA than group A. CONCLUSION: MIST is feasible, safe and it may reduce the composite outcome of death or BPD for VLBW infants with RDS requiring surfactant replacement therapy.

[Effects of UV-B radiation on the growth and reproduction of Vicia angustifolia].

A simulation experiment with supplementation and exclusion of solar ultraviolet-B (UV-B) radiation was conducted to study the effects of enhanced and near ambient UV-B radiation on the growth and reproduction of alpine annual pasture Vicia angustifolia on Qinghai-Tibet Plateau. Enhanced UV-B decreased the plant height and biomass, biomass allocation to fruit, flower number, and 100-seed mass significantly, delayed flowering stage, increased the concentration degree of flowering and success rate of reproduction, but had little effect on seed yield. Near ambient UV-B radiation made the plant height increased after an initial decrease, decreased biomass allocation to fruit and 100-seed mass, but little affected flowering duration, flower number, and seed yield. Both enhanced and near ambient UV-B radiation could inhibit the growth and production of V. angustifolia, and the effect of enhanced UV-B radiation was even larger.

Elevated expression of Foxp3 in tumor-infiltrating Treg cells suppresses T-cell proliferation and contributes to gastric cancer progression in a COX-2-dependent manner.

The transcription factor Foxp3 plays a key role in CD4(+)CD25(+) regulatory T (Treg) cell function. A correlation has been shown between survival and the frequency of tumor-infiltrating Foxp3-positive Treg cells in cancer patients. However, few studies have characterized the regulation of Foxp3 expression and function in Treg cells, which are known to comprise distinct subsets, with different roles in the complex tumor microenvironment. Here, we show that significantly more Foxp3-positive Treg cells accumulated in gastric tumors. In addition, we found increased expression of Foxp3 protein per cell in tumor-infiltrating Treg cells. Moreover, elevated Foxp3 expression in tumor-infiltrating Treg cells was associated with the TNM stage in gastric cancer patients. Importantly, further investigation within the tumor microenvironment showed that expression of Foxp3 in Treg cells correlated with expression of cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)). Furthermore, Treg cells with higher levels of Foxp3 were able to suppress the proliferation of autologous CD4(+)CD25(-) T cells. The suppression of the effector T-cell response was reversed by COX inhibitors and PGE(2) receptor-specific antagonists. Our data demonstrate a mechanism by which tumor-infiltrating Treg cells with increased Foxp3 expression can mediate immune suppression via COX-2/PGE(2) production in the gastric cancer microenvironment. Thus, we provide new insights into overcoming regulatory T-cell activity, which may be beneficial for the treatment of human gastric cancer.

[The clinical features of postoperative ventilator-associated pneumonia after lung surgery].

OBJECTIVE: To investigate the clinical features of postoperative ventilator-associated pneumonia (VAP) after lung surgery. METHODS: Of 104 patients who had undergone lung surgery and been treated with ventilator in our surgical intensive care unit between January 2003 and March 2005, 35 patients met with the criteria of both VAP and postoperative pneumonia (POP), and 41 cases had no evidences of pneumonia. The clinical and laboratory data of all 76 cases were recorded and analyzed by a statistical software package (SPSS). RESULTS: The diagnosis of postoperative VAP was established clinically in 35 patients (46.1%), and etiologically in 33 cases. Compared to the patients without postoperative VAP, the patients with postoperative VAP had a significantly longer mean interval between intubation and operation [(2.7 +/- 2.9) days vs. (1.6 +/- 1.7) days, P = 0.039], a longer duration of mechanical ventilation [(32.2 +/- 37.7) days vs. (4.2 +/- 2.9) days, P < 0.001], and higher morbidity (20.0% vs. 2.4%, P = 0.013). There was a significant difference in mean duration of mechanical ventilation between the 15 cases of early-onset VAP and 20 cases of late-onset VAP (17 +/- 15 days vs. 43 +/- 46 days, P = 0.042). Among the initially detected pathogen, Staphylococcus aureus remains the most common Gram-positive coccus whereas Acinetobacter Baumannii took the place of Pseudomonas aeruginosa as the top Gram-negative rod. CONCLUSION: Postoperative VAP after lung surgery has different clinical features from VAP in medical ICU.

[The impact on perioperative patients with non-small cell lung cancer by neoadjuvant chemotherapy].

BACKGROUND: To investigate whether neoadjuvant chemotherapy (MVP) could influence the safety of perioperative patients with non-small cell lung cancer (NSCLC). METHODS: The regimen of chemotherapy was MVP (mitomycin+vindesine+cisplatin) for all patients. The patients undergoing 2 cycles of neoadjuvant chemotherapy, radical resection and 2 cycles of postoperative chemotherapy were compared with those undergoing similar resections and 4 cycles of similar postoperative chemotherapy. RESULTS: Of the 107 eligible patients, 66 patients were in the neoadjuvant-chemotherapy group and 41 in control group. There was no statistical difference between these two groups in the distributions of gender, age, tumor staging and pathology. The neoadjuvant-chemotherapy group had longer operative duration (P=0.262), more operative blood loss (P=0.704), more amount of operative transfusion (P=0.811) and total amount of perioperative transfusion (P=0.074), and less amount of post-operative drainage (P=0.061) than those of the control group, but no statistical difference was found among them. No statistical difference was detected between two groups in the mortality (P=0.674) and the morbidity such as arrhythmia (P=0.608), bronchial parietal fistula (P= 0.378 ), pneumonia (P=0.622) and respiratory failure (P=0.285). CONCLUSIONS: Neoadjuvant chemotherapy does not exert significant influence on the safety of perioperative patients with NSCLC.