Plant-based vaccines: unique advantages

Numerous studies have shown that viral epitopes and subunits of bacterial toxins can be expressed and correctly processed in transgenic plants. The recombinant proteins induce immune responses and have several benefits over current vaccine technologies, including increased safety, economy, stability, versatility and efficacy. Antigens expressed in corn are particularly advantageous since the seed can be produced in vast quantities and shipped over long distances at ambient temperature, potentially allowing global vaccination. We have expressed the B-subunit of Escherichia coli heat-labile enterotoxin and the spike protein of swine transmissible gastroenteritis virus at high levels in corn, and demonstrate that these antigens delivered in the seed elicit protective immune responses.     

God in control: women's perspectives on managing HIV infection

Women with HIV face a number of challenges in living with this chronic, life-threatening illness: economic, physical, social, and emotional. When discussing their illness the importance these women place on having a strong spiritual life is a consistent theme. In this study, women were asked to describe and explain what spirituality meant to them and how they used it in living with HIV. The results indicate that, in opposition to what some contemporary providers fear HIV-positive women use their spiritual life to enhance the care prescribed by providers, rather than using their faith to avoid mainstream sources of care. In addition, women related the importance of spirituality in dealing with everyday life. Knowledgeable providers can incorporate discussions of spirituality in their care of women with HIV and, in the process, potentially improve the therapeutic results of their HIV-specific care.     

Dynamic coronary MR angiography and first-pass perfusion with intracoronary administration of contrast agent

PURPOSE: To evaluate whether dynamic imaging of the coronary arteries can be performed with intracoronary infusion of low-dose gadolinium (Gd)-based contrast agent and assess the effect of long duration and multiple infusions on the image signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). MATERIALS AND METHODS: Dynamic coronary magnetic resonance (MR) imaging (130 msec/image) and contrast agent first pass myocardial perfusion studies were performed with intracoronary infusions of low-dose Gd-based MR contrast agent on dogs (N = 4) using a fast multislice gradient recalled echo (GRE) sequence. RESULTS: Contrast-enhanced coronary arteries were clearly imaged during infusion periods as long as 2.3 minutes. The SNR and CNR of the contrast-enhanced coronary arteries remained essentially unchanged over multiple consecutive angiographic sessions. In addition, we demonstrated that first pass studies performed with intracoronary injection of MR contrast agent can be used as a means of assessing regional myocardial perfusion. CONCLUSION: These studies demonstrated that, using intracoronary infusion of Gd, coronary magnetic resonance angiography (MRA) can be performed with high temporal resolution, and multiple low-dose slow infusions of Gd-based MR contrast agent can be performed without compromise of the vessel SNR and CNR.     

Gene expression of plasminogen activation cascade components in human term gestational tissues with labour onset

The plasminogen activation cascade is thought to play a critical role in labour-associated remodelling events, such as fetal membrane rupture and placental separation. The aim of this study was to quantify, by Northern analysis, the gene expression of urokinase plasminogen activator (UPA), urokinase receptor (UPAR) and plasminogen activator inhibitor type-2 (PAI-2) in human gestational tissues. Amnion, choriodecidua and placenta were collected from women before, during and after spontaneous-onset labour at term. The expression of UPAR mRNA was significantly (P < 0.05) increased in amnion tissue during and after labour and delivery, compared with the before-labour group. In contrast, UPAR gene expression in choriodecidua and placenta was not significantly altered in association with labour onset. PAI-2 mRNA expression was also significantly (P < 0.05) increased in amnion after labour. No statistically significant differences were observed in choriodecidua or placenta PAI-2 mRNA with labour onset. Neither was any significant effect of labour status on UPA mRNA identified in any of the tissues examined. This study is the first to describe a significant increase in UPAR and PAI-2 gene expression in human amnion tissue with labour. These data are consistent with the hypothesis that, during labour, up-regulation of UPAR expression in amnion serves to localize active UPA at the cell surface, thereby increasing proteolytic activity in fetal membranes. Increased PAI-2 in amnion after labour may provide a regulatory 'switch' to cease further proteolysis in this tissue type. In conclusion, the data obtained support the proposal that the plasminogen activation cascade contributes to the rupture of fetal membranes during active labour.      

PAROXYSMAL TACHYCARDIA IN INFANCY AND CHILDHOOD II. Paroxysmal Ventricular Tachycardia and Fibrillation

A retrospective 3–20-years follow-up study of 1 infant and 10 children with paroxysmal ventricular tachycardia (8 cases) or fibrillation (3 cases) is presented. Additional heart disease has been observed in 60% (myocarditis 3 cases, cardiomyopathy 3 cases, congenital heart disease 1 case). Symptoms of tachycardia were: palpitation, tiredness, weakness, dyspnoea, precordial and abdominal pain. Syncopes were observed in 3 cases; 1 child had no symptoms. Tachycardia of hours to days' duration have been noted in 8 patients, 7 had tachycardia of repetitive type with a-v dissociation, one continuous tachycardia without any intervening sinus beats after the onset of tachycardia and with retrograde atrial activation. The remaining 3 children had brief malignant tachycardia, i.e. stress-provoked bursts of ventricular activity occasionally converting to ventricular fibrillation causing syncope. The diagnosis of brief malignant tachycardia had to be based on exercise ECG (2 cases) or long-term ECG-monitoring by telemetry (one case). One child with cardiomyopathy had died at the time of follow-up and the 3 patients with brief malignant tachycardia had experienced repeated life-threatening attacks—one of which had to be stopped by emergency d.c. countershock. The period of attacks ceased in 5 cases within 2 years after onset, in 1 patient, 9 years elapsed between first and second attack. Preventive treatment with betablocking agents proved beneficial in the 3 children with brief malignant tachycardia.     

Neuropsychological and behavioral status of children with complex partial seizures

Neuropsychological and behavioral status were examined in 57 children aged 7 to 16 years with complex partial seizures (CPS) and compared with 27 sibling control children of the same age. Epilepsy had a significant effect on both cognitive and behavioral adjustment measures. Children with CPS had significant impairment across all seven cognitive domains assessed, reflective of a profile of relatively diffuse and generalized cognitive dysfunction. Age at onset of recurrent seizures was the strongest and most consistent predictor of adequacy of cognitive functioning; earlier age at onset was associated with poorer cognitive status. Children with CPS also had more problems compared with sibling control children on measures of social and school competence and internalizing behavior problems, but not externalizing behaviors. Further, frequency of seizure activity in the past year, rather than age at seizure onset, emerged as the strongest predictor of these behavioral difficulties. These findings are discussed in the context of understanding the impact of CPS on cognition and behavioral adjustment, and identifying the contribution of various aspects of the neurodevelopmental course of CPS to these issues.