Differential transforming growth factor-beta secretion in adenocarcinoma and squamous cell carcinoma of the uterine cervix

Tumor cells from eight freshly isolated cervical cancers (i.e., four adenocarcinomas and four squamous carcinomas) were analyzed for their production of the immune-inhibitory cytokine transforming growth factor-beta (TGF-beta) in vitro. All fresh adenocarcinomas secreted significant levels of TGF-beta (mean 397, range between 207 and 782 pg/ml/10(5) cells/48 hr). In contrast, no detectable TGF-beta was present in the supernatants from the four fresh squamous carcinoma cultures (P < 0.001). These data suggest that major differences in the secretion of the immunoinhibitory cytokine TGF-beta exist between squamous cell carcinomas and adenocarcinomas of the uterine cervix. Furthermore, these findings suggest that at least some of the differences in the natural biologic behavior, as well as in the response to radiation treatment, between these two histologic types of cervical cancer could be related to differences in secretion of this immune-inhibitory cytokine.     

A simple handling technique for mammalian oocytes and embryos during preparation for transmission electron microscopy

Due to their small size, mammalian oocytes and embryos pose unique problems during preparation for transmission electron microscopy. This paper outlines a method which combines protein embedding with centrifugation to locate the specimens on the face of a Beem capsule mould. This method facilitates both the processing of oocytes with minimal loss and rapid location of the specimens within the block for simultaneous sectioning, staining and examination.     

Isoforms p69 and p100 of 2'',5''-oligoadenylate synthetase induced differentially by interferons in vivo and in vitro

There is no better place to test life-saving resuscitation interventions than in the prehospital setting. Patients rarely survive cardiac arrest if resuscitation techniques have failed before leaving the scene. Also, paramedics are usually very experienced in key initial resuscitative techniques, and they routinely operate under strict paramilitary protocol, resulting in better study compliance. In addition, the large study populations that are derived from emergency medical services (EMS) systems lead to faster study completion and statistically stronger data. Most important, by reinforcing standardized care, rigidly scrutinized trials improve patient care, regardless of the effect of the study intervention. The success of productive EMS research centers requires routine communication between hospital and EMS administrators and their medical directors, designation of mutually acceptable data collectors who guarantee confidentiality, reciprocal exchange of study data provided as educational seminars to the hospitals, commitments to support the budget requests of an EMS program and appropriate system modifications, inclusion of EMS personnel in study design from the very beginning, prospective education of the medical community and media before protocol implementation, an authoritative grassroots medical director, and a paramedic supervisor system.     

Frontiers in research on cystic fibrosis: understanding its molecular and chemical basis and relationship to the pathogenesis of the disease

In recent years a new family of transport proteins called ABC transporters has emerged. One member of this novel family, called CFTR (cystic fibrosis transmembrane conductance regulator), has received special attention because of its association with the disease cystic fibrosis (CF). This is an inherited disorder affecting about 1 in 2000 Caucasians by impairing epithelial ion transport, particularly that of chloride. Death may occur in severe cases because of chronic lung infections, especially by Pseudomonas aeruginosa, which cause a slow decline in pulmonary function. The prospects of ameliorating the symptoms of CF and even curing the disease were greatly heightened in 1989 following the cloning of the CFTR gene and the discovery that the mutation (deltaF508), which causes most cases of CF, is localized within a putative ATP binding/ATP hydrolysis domain. The purpose of this introductory review in this minireview series is to summarize what we and others have learned during the past eight years about the structure and function of the first nucleotide binding domain (NBF1 or NBD1) of the CFTR protein and the effect thereon of disease-causing mutations. The relationship of these new findings to the pathogenesis of CF is also discussed.