Dihydrotestosterone decreases beta-adrenergic receptor binding in the fetal rabbit lung

Tritium-labeled dihydroalprenolol was used to quantify the beta-adrenergic receptor sites in day 30 fetal rabbit lung tissue. Each of the fetuses of New Zealand White rabbits on day 28 of gestation was injected with dihydrotestosterone (2.0 micrograms) in one horn of the uterus and 10% ethanol in normal saline (the solvent) in the contralateral one. The animals were sacrificed 48 hours later and the fetal lung tissue was assayed. Dihydrotestosterone decreased the beta-adrenergic receptor site number in the treatment group compared with the control group (86 versus 111 fmol/mg protein, p less than 0.05 by paired t-test). In the presence of dihydrotestosterone, beta-adrenergic receptor binding is inhibited in the preterm fetal rabbit. This effect may be implicated in the beta-adrenergic mediation of phospholipid synthesis and/or release by fetal alveolar cells.     

Process development for a Cuban cholera vaccine based on the attenuated strain Vibrio cholerae 638

Genetically modified Vibrio cholerae strain 638 (biotype El Tor, serotype Ogawa) has previously been shown to be immunogenic in animal models and in human trials. Our objective in the work reported herein was to describe the process development methods for the production of the 638 attenuated cholera vaccine. Cell seed bank, culture of biomass, lyophilization and final formulation were processes were developed. The results show kinetics of culture that fulfils a logistical model. The microbiological properties, colonizing capability, immunogenicity and non-toxigenicity of the final product were indistinguishable from the properties of the working seed lot. We conclude that the non-reactogenic, immunogenic and protective strain 638 is robust and can withstand the fermentation processes required for large-scale production of a vaccine.     

MRI of perfluorocarbon emulsion kinetics in rodent mammary tumours

Perfluorocarbon (PFC) emulsions can be imaged directly by fluorine-19 MRI. We developed an optimized protocol for preparing PFC droplets of uniform size, evaluated use of the resulting droplets as blood pool contrast agents, studied their uptake by tumours and determined the spatial resolution with which they can be imaged at 4.7 T. Perfluorocarbon droplets of three different average sizes (324, 293 and 225 nm) were prepared using a microemulsifier. Images of PFC droplets with good signal-to-noise ratio were acquired with 625 microm in-plane resolution, 3 mm slice thickness and acquisition time of approximately 4.5 min per image. Kinetics of washout were determined using a simple mathematical model. The maximum uptake of the PFC droplets was three times greater at the tumour rim than in muscle, but the washout rate was two to three times slower in the tumour. The results are consistent with leakage of the droplets into the tumour extravascular space due to the hyper-permeability of tumour capillaries. PFC droplets may allow practical and quantitative measurements of blood volume and capillary permeability in tumours with reasonable spatial resolution.     

实施心理干预对抗青光眼术后患者焦虑和皮质醇的影响

目的 观察心理干预对青光眼手术患者情绪焦虑、皮质醇及术后前房恢复的影响。方法将入选住院病人68例随机分为治疗组和对照组，2组病人均给予常规降低眼压和青光眼手术治疗，治疗组同时实施支持性心理干预和放松训练等，观察治疗前后2组病人的焦虑情绪和血皮质醇变化及术后前房恢复情况。结果 治疗组患者术后焦虑情绪和血皮质醇较对照组明显降低，前房恢复较快。结论 心理干预可降低手术应激引起的青光眼患者情绪焦虑和血皮质醇的分泌增加，促进青光眼患者术后的好转。     

葛根素双相动态提取工艺优化研究

目的:研究葛根中葛根素的最佳双相动态提取工艺。方法:以葛根素提取率为主要指标,出膏率为次要指标,采用L9(34)正交试验设计对提取工艺进行优化,考查硫酸浓度、溶剂倍数、提取时间、提取次数对葛根素含量的影响。结果:葛根素的最佳提取工艺为浓度2.0%的硫酸,12倍量溶剂1,00℃,提取2次,提取时间1.5 h。结论:优选得到的工艺稳定,重复性好,便于质量控制和工业化生产。     

Formulation in tablets of a cholera whole cells inactivated vaccine candidate

Licensed as well as candidate cholera vaccines available at the present requires the dose preparation (included buffer) at the moment of application. The aim of this work was to evaluate the presentation in oral tablets of an inactivated cholera vaccine to avoid that inconveniences during application. We have therefore compared inactivated cultures of Vibrio cholerae with tablets formulation vaccine. We obtained that antigenic activity (ELISA) and immunogenicity in animal model (ELISA and vibriocidal tests) of V. cholerae inactivated cell remained unaltered in the final tablet formulation. The results suggest that the oral tablet formulation could be a useful pharmaceutical form in order to produce a new and affordable cholera vaccine.     

Five-year survival for cisplatin-based chemotherapy versus single-agent melphalan in patients with advanced ovarian cancer and optimal debulking surgery

The purpose of this study was to evaluate 5-year survival and 5-year progression-free survival in previously untreated patients with advanced ovarian cancer treated with single-agent melphalan in which very few patients underwent optimal debulking surgery (less than 2 cm residual) as compared with the patients treated with Cisplatin-based chemotherapy in which most patients underwent optimal debulking surgery. Significant increases in 5-year survival and 5-year progression-free survival were noted as we changed from the melphalan trial, in which only 14% underwent optimal debulking surgery, to PAC-H, in which 57% and the PAC trial in which 90%, respectively, underwent optimal debulking surgery. However, for those patients whose tumors were optimally debulked in the three trials, there were no statistically significant differences in median survival, median progression-free survival, 5-year survival, or 5-year progression-free survival in those patients treated with melphalan, PAC-H, or PAC. Without optimal debulking surgery, Cisplatin-based multiagent chemotherapy offered a small survival advantage. These results are similar to that reported by Gruppo Interregionale Cooperativo Oncologico Ginecologia, in which survival curves were identical for all the subgroups of chemotherapy regimens for those patients with residual disease less than 2 cm at the onset of chemotherapy whether they received (1) cyclophosphamide; (2) cyclophosphamide and Adriamycin; (3) cyclophosphamide, Adriamycin, and Cisplatin; (4) cyclophosphamide, Adriamycin, and hexamethylmelamine; (5) Cisplatin and cyclophosphamide; (6) low-dose Cisplatin; (7) high-dose Cisplatin; or (8) carboplatin.     

Comparison of high-resolution echo-planar spectroscopic imaging with conventional MR imaging of prostate tumors in mice

High spectral and spatial resolution (HiSS) MRI of rodent tumors has previously been performed using conventional spectroscopic imaging to obtain images with improved contrast and anatomic detail. The work described here evaluates the use of much faster echo-planar spectroscopic imaging (EPSI) to acquire HiSS data from rodent tumor models of prostate cancer. A high-resolution EPSI pulse sequence was implemented on a 4.7 T Bruker scanner. Three-dimensional EPSI data were Fourier-transformed along the k-space and temporal (free-induction decay) axes to produce detailed water and fat spectra associated with each small image voxel. The data were used to generate images of spectral parameters, e.g. peak-height images for each small voxel. Two variants of EPSI were performed; gradient-echo or spin-echo excitation with EPSI readout. These imaging methods were tested in commonly used rodent prostate cancers, including seven mice implanted with non-metastatic AT2.1 (n=3) and metastatic AT3.1 (n=4) prostate tumors on the hind leg, and 10 mice implanted with LNCaP prostate cancers in situ. The peak-height images derived from EPSI datasets provide more detailed tumor anatomy, improved signal-to-noise and contrast-to-noise ratios compared with the gradient-echo or spin-echo images at all echo times. The results suggest that HiSS MRI data from small animal models of prostate cancer can be acquired using EPSI, and that this approach improves imaging of heterogeneous tissue and vascular environments inside the tumors compared with conventional MR techniques.     

Escherichia coli producing CTX-M beta-lactamases in food animals in Hong Kong

A study was conducted to evaluate the occurrence of extended-spectrum beta-lactamases (ESBLs)-producing Escherichia coli from fecal samples of healthy food animals in Hong Kong. Rectal or cloacal swabs were obtained from cattle, pigs, chicken, ducks, geese, and pigeons in slaughterhouses or wholesale markets over a 5- month period in 2002. Antibiotic-containing medium was used for selective isolation of potentially ESBL-producing E. coli. Of 734 samples analyzed, six (2%) from pigs, three (3.1%) from cattle, and one (3%) from pigeons had E. coli strains with the ESBL phenotype. The ESBL content for the 10 isolates include CTXM- 3 (n = 4), CTX-M-13 (n = 3), CTX-M-14 (n = 2), and CTX-M-24 (n = 1). In five isolates, the bla (CTX-M) gene was encoded on transferable plasmids (60 or 90 kb), and the gene was found to transfer to E. coli (J53 or JP995) with frequencies of 10(7) to 10(3) per donor cells. The ten isolates had five distinct pulsotypes with some clonal spread. However, the isolates from the different kinds of animals were not clonally related. These findings imply that bacteria of animal origins may serve as reservoirs of some ESBL genes.