Macrophage colony-stimulating factor can modulate immune responses and attract dendritic cells in vivo

Studies have indicated that professional APCs in the periphery, such as dendritic cells and macrophages, play an important role in initiating DNA vaccine-specific immune responses. To engineer the immune response induced by DNA vaccines in vivo we investigated the modulatory effects of codelivering growth factor genes for the hematopoietic APCs along with DNA vaccines. Specifically, we examined the effects on the antigen-specific immune responses following the codelivery of the gene expression cassettes for M-CSF, G-CSF, and GM-CSF along with HIV-1 DNA immunogen constructs. We observed that coimmunization with GM-CSF increased the antibody response and resulted in a significant enhancement of lymphoproliferative response. Furthermore, among all coinjection combinations, we found that M-CSF coinjections resulted in a high level of CTL enhancement. This enhancement of CTL responses observed from the coinjection with M-CSF was CD8+ T cell dependent and was associated with the presence of CD11c+ cells at the site of injection and with the antigen-specific induction of the beta-chemokine MIP-1beta, suggesting a role for this chemokine in CTL induction. These results suggest that hematopoietic growth factors should be further studied as potential adjuvants for in vivo modulators of immune responses.     

Hypertension in the young adult--come feel the pulse

Hypertension occurring in teenagers and young adults is uncommon. Though the most common form is still essential hypertension, secondary causes are more commonly found here than in older adults. Renal, cardiovascular and endocrine diseases constitute most of these causes. Coarctation of the aorta is the most common cardiovascular cause of hypertension, and its importance lies in the fact that it is correctable, and that its persistence often leads to dangerous complications and early death. The cardinal sign of differential pulse and blood pressures between the upper and lower limbs can be detected clinically. Hence, the importance of a detailed physical examination in all young hypertensives, including palpation of all the pulses, cannot be overemphasized. We present 2 hypertensive young men who were found to have isolated coarctation of the aorta. The lesion in the first patient was located postductally just distal to the left subclavian artery. This area has been found to be the most common site of coarctation. The second patient had an unusual mid-thoracic coarctation. The clinical and radiological features as well as complications are highlighted. In young hypertensive patients, a high index of suspicion may enable the physician to make a timely diagnosis and hence avert the potentially disastrous complications that may arise in undetected cases.     

Why do Some Countries Publish More Than Others? An International Comparison of Research Funding, English Proficiency and Publication Output in Highly Ranked General Medical Journals

National factor(s) influencing publication output in the highest ranked medical journals are largely unknown. We sought to examine the relationship between national research funding and English proficiency on publication output. We identified all original research articles appearing in the five highest ranked general medical journals between 1997 and 2001. Using the country of the corresponding author as the source nation for each article, we determined a standardized publication rate across developed nations. We used multiple regression techniques to determine the influence of national expenditures on research and scores from the Test of English as a Foreign Language (TOEFL), a surrogate for English proficiency, on publication output. There was a significant relationship of national spending on research and TOEFL scores to publication output of developed countries (p = 0.04; p < 0.01, respectively). These two variables explained approximately 71.5% of the variation in publication rate across developed nations around the world (R = 0.85; p < 0.01). Normalized for population size, English-speaking nations and certain northern European countries such as Denmark, The Netherlands, Switzerland, and Sweden had the highest rate of publication in the five highest ranked general medical journals, while Asian countries had generally low rates of publication. Research spending and English proficiency were strongly associated with publication output in the highest ranked general medical journals. While these data cannot be considered definitive due to their observational nature, they do suggest that for English-language medical journals, research funding and English proficiency may be important determinants of publication.     

Virus-specific RNA and antibody from convalescent-phase SARS patients discharged from hospital

Severe acute respiratory syndrome (SARS) is caused by a novel coronavirus (SARS-CoV). In a longitudinal cross-sectional study, we determined the prevalence of virus in bodily excretions and time of seroconversion in discharged patients with SARS. Conjunctival, throat, stool, and urine specimens were collected weekly from 64 patients and tested for SARS-CoV RNA by real-time polymerase chain reaction; serum samples were collected weekly and tested for SARS-CoV antibody with indirect enzyme immunoassay and immunofluorescence assay. In total, 126 conjunctival, 124 throat swab, 116 stool, and 124 urine specimens were analyzed. Five patients had positive stool samples, collected in weeks 5-9. Two patients seroconverted in weeks 7 and 8; the others were seropositive at the first serum sample collection. In this study, 5 (7.8%) of 64 patients continued to shed viral RNA in stool samples only, for up to week 8 of illness. Most seroconversions occurred by week 6 of illness.