A novel DNA-peptide complex for efficient gene transfer and expression in mammalian cells

To develop a nonviral gene delivery system for treatment of diseases, our strategy is to construct DNA complexes with short synthetic peptides that mimic the functions of viral proteins. We have designed and synthesized two peptides which emulate viral functions - a DNA condensing agent, YKAK(8)WK, and an amphipathic, pH-dependent endosomal releasing agent, GLFEALLELLESLWELLLEA. The active gene delivery complex was constructed step-wise through a spontaneous self-assembly process involving oppositely charged, electrostatic interactions. To assemble DNA-peptide complexes with different overall net charges, only the negative charges of DNA phosphate, the positive charges of the 10 epsilon-amino groups of YKAK(8)WK and the negative charges of the 5 gamma-carboxyl groups of GLFEALLELLESLWELLLEA were considered. In the first step, negatively charged DNA was rapidly-mixed with an excess of YKAK(8)WK to form positively charged DNA-YKAK(8)WK complexes, which gave little gene transfer. In the second step and to form the active complex,the cationic DNA complex was rapidly mixed with spontaneously incorporated through electrostatic interactions. Transfection using these complexes of CMV-luc, YKAK(8)WK and GLFEALLELLESLWELLLEA gave high-levels of gene expression in a variety of cell lines. These simple DNA complexes, which contain only three molecularly defined components, have general utility for gene delivery and can replace viral vectors and cationic lipids for some applications in gene therapy.     

Characterization of emissions of dioxins and furans from ethylene dichloride (EDC), vinyl chloride (VCM) and polyvinylchloride (PVC) manufacturing facilities in the United States. I. Resin, treated wastewater, and ethylene dichloride

Under the auspices of its Dioxin Characterization Program, members of The Vinyl Institute (VI), have analyzed for potential polychlorinated dibenzodioxin/furan (PCDD/F) concentrations in polyvinylchloride (PVC) resins, treated wastewater effluent and ethylene dichloride (EDC) product at EDC, vinyl chloride monomer (VCM) and PVC manufacturing facilities in the U.S. and Canada. No 2,3,7,8-tetrachlorodibenzodioxin (TCDD) was detected in any sample analyzed under the program to date. Trace concentrations (low pg/g) of PCDD/F were detected in only a few samples of PVC resins and EDC product. Treated wastewater contained low ppq concentrations of PCDD/F. All concentrations are expressed as Toxic Equivalents (TEQ). Extrapolation of these data shows that the contribution of EDC/VCM/PVC manufacturing via these media constitutes substantially less than 1 percent of the estimated annual U.S. dioxin releases to the environment.     

Circulating concentrations of insulin-like growth factor-I and risk of breast cancer

BACKGROUND: Insulin-like growth factor (IGF)-I, a mitogenic and antiapoptotic peptide, can affect the proliferation of breast epithelial cells, and is thought to have a role in breast cancer. We hypothesised that high circulating IGF-I concentrations would be associated with an increased risk of breast cancer. METHODS: We carried out a nested case-control study within the prospective Nurses' Health Study cohort. Plasma concentrations of IGF-I and IGF binding protein 3 (IGFBP-3) were measured in blood samples collected in 1989-90. We identified 397 women who had a diagnosis of breast cancer after this date and 620 age-matched controls. IGF-I concentrations were compared by logistic regression with adjustment for other breast-cancer risk factors. FINDINGS: There was no association between IGF-I concentrations and breast-cancer risk among the whole study group. In postmenopausal women there was no association between IGF-I concentrations and breast-cancer risk (top vs bottom quintile of IGF-I, relative risk 0.85 [95% CI 0.53-1.39]). The relative risk of breast cancer among premenopausal women by IGF-I concentration (top vs bottom tertile) was 2.33 (1.06-5.16; p for trend 0.08). Among premenopausal women less than 50 years old at the time of blood collection, the relative risk was 4.58 (1.75-12.0; p for trend 0.02). After further adjustment for plasma IGFBP-3 concentrations these relative risks were 2.88 and 7.28, respectively. INTERPRETATION: A positive relation between circulating IGF-I concentration and risk of breast cancer was found among premenopausal but not postmenopausal women. Plasma IGF-I concentrations may be useful in the identification of women at high risk of breast cancer and in the development of risk reduction strategies. Additional larger studies of this association among premenopausal women are needed to provide more precise estimates of effect.     

Endothelial cell proliferation follows the mid-cycle luteinizing hormone surge, but not human chorionic gonadotrophin rescue, in the human corpus luteum

The corpus luteum is essential for the maintenance of early pregnancy in women. Angiogenesis may be one factor involved in luteal rescue. The aim of this study was to determine the changes in endothelial cell proliferation throughout the luteal phase and in human chorionic gonadotrophin (HCG)-simulated early pregnancy. Human corpora lutea obtained throughout the luteal phase and in simulated early pregnancy were immunostained with antibodies for endothelial and proliferating cells. Number and distribution of endothelial and proliferating cells were examined. Endothelial cells were least abundant in the early luteal phase, increasing in the mid-luteal phase (P < 0.03). Endothelial numbers did not differ significantly between the late and the rescued corpora lutea. Endothelial cell proliferation was greatest in the early luteal phase and continued at a lower level during later stages. Simulated early pregnancy resulted in no change in endothelial cell proliferation. These results showed that a high degree of endothelial cell proliferation is associated with formation of the human corpus luteum. Unchanging levels of proliferation following HCG treatment (for 5-8 days from day 12 to day 16 post-ovulation, at 125 IU to 16,000 IU, following a daily doubling of dose) suggest that alternative processes are involved during luteal rescue.     

Autograft failure after the Ross operation in a rheumatic population: pre- and postoperative echocardiographic observations

BACKGROUND AND AIMS OF THE STUDY: Between January 1990 and July 1995, 108 patients underwent the Ross operation at our hospital. Most patients (90%) had severe aortic regurgitation (AR) in the setting of rheumatic heart disease. Although there have been no perioperative or late cardiac deaths, 12 patients (11%) developed severe AR requiring reoperation. MATERIAL AND METHODS: We performed an extensive and mostly retrospective analysis of echocardiographic data on all patients. Preoperative data were analyzed for age, sex, body surface area (BSA), size and comparison of the left and right ventricular outflow tracts (LVOT, RVOT), left ventricular (LV) size and function, and the presence of pulmonary regurgitation (PR) and concomitant mitral regurgitation (MR). Follow up data were analyzed for the presence, time of onset, evolution and severity of AR, characteristics of the AR jet, anatomic and functional aspects of the aortic root and valve, and evolution of LVOT diameter and LV size and function. RESULTS: Patients with autograft failure were younger with smaller BSA, larger indexed size of LVOT, RVOT and LV, and significantly more had concomitant severe MR. Postoperatively they had larger and increasing LVOT size. Trivial or mild AR was common and seen in almost all patients, as was a minimal degree of preoperative PR. Severe AR developed mostly after the first year of follow up, and reoperation was performed within three years in 11/12 patients. In nine patients cusp dilatation and prolapse (most frequently of the posterior cusp) was the cause of the AR, and rheumatic activity in three. Reoperation was not associated with mortality. CONCLUSION: In our population autograft failure seems to be related to age, BSA and (indexed) LVOT, RVOT and LV size, but only the presence of significant concomitant mitral regurgitation before surgery was identified as a predictor for reoperation. Prolapse of one or more cusps were the cause of the AR in most patients. The graft is sensitive for recurrent rheumatic activity.     

Neostigmine decreases heart rate in heart transplant patients

Calretinin is an "EF-hand" calcium-binding protein involved in the maintenance of intracellular calcium ion homeostasis. This study was undertaken to investigate the presence of calretinin in human lumbar paravertebral sympathetic ganglia from subjects of different ages (26-85 years) using immunohistochemical and immunoblotting methods. Calretinin-like immunoreactivity was found in a subpopulation of postganglionic sympathetic neurons, whose percentage decreased progressively with aging by about 50% (63% of immunoreactive neurons at < or = 40 years; 29% at > or = 81 years) whereas the neuronal density remained basically unchanged. Calretinin-like immunoreactivity showed a granular pattern of cytoplasmic distribution suggesting preferential localization of this protein associated with intracellular membranes. Occasionally diffuse cytosolic labelling was also observed. The immunoblotting demonstrated a protein band with an estimated molecular weight of 30 kDa, approximately. Present results provide, for the first time, evidence for the presence of calretinin in human paravertebral sympathetic ganglia. Since the number of calretinin-like immunoreactive neurons decreased significantly with aging our findings suggest an involvement of this protein in the age-dependent impairment of sympathetic function.     

Neurosurgery at the State University of New York at Buffalo

We treated five patients with auricular deformities (microtia in microform and group IIB or III constricted ears) using the following procedure: nearly all of the contralateral conchal cartilage was resected, grafted, and sutured to supplement a cartilaginous deficit and to keep the supporting frame of conchal cartilage expanded by the double banner flap method. After this, a soft tissue deficit was reconstructed by our newly developed method of covering the defect with a triangular flap superior to the auricle by making a skin incision and a rhomboid flap anterior to the auricle. So far, we have obtained satisfactory results using this one-stage procedure.     

Effect of plumbagin on the radiation induced cytogenetic and cell cycle changes in mouse Ehrlich ascites carcinoma in vivo

BACKGROUND: Controversy exists concerning whether the costs and potential risks outweigh the potential benefits of "crossover" use in the general blood supply of unutilized blood that was donated for autologous transfusion. STUDY DESIGN AND METHODS: Published articles and reports were identified through systematic search of MEDLINE and review of references cited in previously identified articles, textbooks, and reports. Consultation was made with experts in blood donation and transfusion. Additional peer review was received from the American Medical Association (AMA) Council on Scientific Affairs RESULTS: Concern over infectious disease transmission has led to increased interest in and support for autologous transfusion for individuals having planned surgeries. Different requirements exist for collection, labeling, and screening of blood to be used for autologous versus allogeneic transfusions; therefore, procedures for diverting autologous blood donations to the general blood supply involve considerable expense. Several cost-effectiveness studies of autologous blood donation and transfusion conclude that currently this "crossover" appears to be an expensive procedure yielding little increased benefit from a societal perspective. CONCLUSIONS: The recommendations in this report were adopted as AMA Policy at the AMA Annual Meeting in June 1997. The AMA does not encourage blood collection programs to "cross over" units donated for autologous use to the allogeneic blood supply. Practice guidelines are needed, and should be utilized to ensure parsimony in the use of autologous blood donations and transfusions.