A bibliometric study of scientific literature on obesity research in PubMed (1988–2007)

This article describes a bibliometric review of the publications on obesity research in PubMed over the last 20 years. We used Medline via the PubMed online service of the US National Library of Medicine from 1988 to 2007. The search strategy was: ([obesity] in MesH). A total of 58 325 references were retrieved, 25.5% in 1988–1997, and 74.5% in 1998–2007. The growth in the number of publications showed an exponential increase. The references were published in 3613 different journals, with 20 journals contributing 25% of obesity literature. The two journals contributing most were the International Journal of Obesity (5.1%), Obesity‐Obesity Research (2.9%). North America and Europe were the most productive world areas with 44.1% and 37.9% of the literature, respectively. The US was the predominant country in number of publications, followed by the United Kingdom, Japan and Italy. The ranking of production changed when the number of publications was normalized by population, gross domestic product and obesity prevalence by countries. The great increase of publications on obesity during the period 1988–2007 was particularly evident in the second decade of the period which is concordant with the worldwide obesity epidemic. USA and Europe were leaders in the production of scientific articles on obesity.     

Prevalence of human T-cell lymphotropic virus type 1 and 2 among patients with malignant hematological diseases in south Chile

Human T-cell lymphotropic virus type 1 and 2 (HTLV-1/2) are oncogenic retroviruses linked etiologically to human diseases. In Chile, these viruses have been studied in ethnic populations, or patients diagnosed clinically with HTLV-1 associated myelopathy/tropical spastic paraparesis, but have not been studied in patients with malignant hematological diseases. The aim of this study was to determine the seroprevalence and viral prevalence of HTLV-1/2 among patients with malignant hematological diseases. Eighty-eight patients with malignant hematological diseases were tested by enzyme-linked immunosorbent assay (ELISA) for IgG anti-HTLV-1/2 and nested-PCR for the tax gene. The seroprevalence by ELISA was 3.4% and the viral prevalence by nested-PCR tax was 18.2%. HTLV-1 was found in 17% and HTLV-2 in 1% of the patients tested. HTLV-1/2 was found in 17.4% of patients with non-Hodgkin's lymphomas, 28.6% of patients with Hodgkin's lymphomas, 80% of patients with chronic lymphocytic leukemia, 11.4% of patients with acute lymphoblastic leukemia, and 22.2% of patients with acute myeloid leukemia. A high prevalence of HTLV-1/2 was found in patients with malignant hematological diseases. A high proportion of patients were seronegative to HTLV-1/2 infection, similar to other HTLV-1/2 associated disorders. Because 50% of patients positive for HTLV-1/2 were below 30 years old, it is suggested that vertical transmission could have played an important role in these patients.     

The prevalence of radiographic vertebral fractures in Latin American countries: the Latin American Vertebral Osteoporosis Study (LAVOS)

Summary  In the first population-based study of vertebral fractures in Latin America, we found a 11.18 (95% CI 9.23–13.4) prevalence of radiographically ascertained vertebral fractures in a random sample of 1,922 women from cities within five different countries. These figures are similar to findings from studies in Beijing, China, some regions of Europe, and slightly lower than those found in the USA using the same standardized methodology. Introduction  We report the first study of radiographic vertebral fractures in Latin America. Methods  An age-stratified random sample of 1,922 women aged 50 years and older from Argentina, Brazil, Colombia, Mexico, and Puerto Rico were included. In all cases a standardized questionnaire and lateral X-rays of the lumbar and thoracic spine were obtained after informed consent. Results  A standardized prevalence of 11.18 (95% CI 9.23–13.4) was found. The prevalence was similar in all five countries, increasing from 6.9% (95% CI 4.6–9.1) in women aged 50–59 years to 27.8% (95% CI 23.1–32.4) in those 80 years and older (p for trend < 0.001). Among different risk factors, self-reported height loss OR = 1.63 (95% CI: 1.18–2.25), and previous history of fracture OR = 1.52 (95% CI: 1.14–2.03) were significantly (p < 0.003 and p < 0.04 respectably) associated with the presence of radiographic vertebral fractures in the multivariate analysis. In the bivariate analyses HRT was associated with a 35% lower risk OR = 0.65 (95% CI: 0.46–0.93) and physical activity with a 27% lower risk of having a vertebral fracture OR = 0.73 (95% CI: 0.55–0.98), but were not statistically significant in multivariate analyses Conclusion  We conclude that radiographically ascertained vertebral fractures are common in Latin America. Health authorities in the region should be aware and consider implementing measures to prevent vertebral fractures.     

Protective effect of fallopian tubal fluid against activated leucocyte-induced sperm DNA fragmentation: preliminary results

The integrity of the paternal genome is of paramount importance in the initiation and maintenance of a viable pregnancy. Oxygen radicals (ROS) have been identified as one of the main factors responsible for the induction of sperm DNA damage. Spermatozoa are mainly protected against ROS-induced damage by seminal plasma. However, this protective effect disappears once spermatozoa enter the female genital tract. The fallopian tube mucosa may play a protective role against ROS-induced sperm damage. The main objective of this study was to determine whether human tubal explants and tubal fluid exert a protective effect on ROS-induced sperm DNA damage. Spermatozoa were exposed to tubal explants and/or tubal fluid in the presence of phorbol myristate acetate (PMA)-activated polymorphonuclear leucocytes or control medium and sperm DNA fragmentation was measured using the TdT-mediated dUTP-biotin nick end labelling (TUNEL) test. Exposure of human spermatozoa to PMA-activated leucocytes resulted in a 2-fold increase in sperm DNA fragmentation. Co-incubation of spermatozoa with tubal explants did not reduce this damage. However, pre-incubation of spermatozoa with tubal fluid resulted in a statistically significant reduction in sperm DNA fragmentation levels, comparable to those observed in control. In conclusion, tubal fluid appears to protect against activated leucocyte-induced sperm DNA fragmentation, thus preserving the integrity of the paternal genome.     

High frequency of large genomic deletions in the PCCA gene causing propionic acidemia

Mutations in either the PCCA or PCCB genes are responsible for propionic acidemia (PA), one of the most frequent organic acidemias inherited in autosomal recessive fashion. Most of the mutations detected to date in both genes are missense. In the case of PCCA deficient patients, a high number of alleles remain uncharacterized, some of them suspected to carry an exonic deletion. We have now employed multiplex ligation probe amplification (MLPA) and long-PCR in some cases to screen for genomic rearrangements in the PCCA gene in 20 patients in whom standard mutation detection techniques had failed to complete genotype analysis. Eight different deletions were found, corresponding to a frequency of 21.3% of the total PCCA alleles genotyped at our center. Two of the exonic deletions were frequent, one involving exons 3–4 and another exon 23 although in the first case two different chromosomal breakpoints were identified. Absence of exons 3 and 4 which is also the consequence of the novel splicing mutation c.231 + 1g > c present in two patients, presumably results in an in-frame deletion covering 39 aminoacids, which was expressed in a eukaryotic system confirming its pathogenicity. This work describes for the first time the high frequency of large genomic deletions in the PCCA gene, which could be due to the characteristics of the PCCA gene structure and its abundance in intronic repetitive elements. Our data underscore the need of using gene dosage analysis to complement routine genetic analysis in PCCA patients.     

A role for exposed mannosylations in presentation of human therapeutic self-proteins to CD4+ T lymphocytes

Several therapeutic self-proteins elicit immune responses when administered to patients. Such adverse immune responses reduce drug efficacy. To induce an immune response, a protein must interact with different immune cells, including antigen-presenting cells, T cells, and B cells. Each cell type recognizes distinct immunogenic patterns on antigens. Mannose-terminating glycans have been identified as pathogen-associated molecular patterns that are essential for internalization of microbes by antigen-presenting cells, leading to presentation. Here, we have investigated the importance of exposed mannosylation on an immunogenic therapeutic self-protein, procoagulant human factor VIII (FVIII). Administration of therapeutic FVIII to hemophilia A patients induces inhibitory anti-FVIII antibodies in up to 30% of the cases. We demonstrate that entry of FVIII into human dendritic cells (DC) leading to T cell activation, is mediated by mannose-terminating glycans on FVIII. Further, we identified macrophage mannose receptor (CD206) as a candidate endocytic receptor for FVIII on DC. Saturation of mannose receptors on DC with mannan, and enzymatic removal of mannosylated glycans from FVIII lead to reduced T cell activation. The interaction between FVIII and CD206 was blocked by VWF, suggesting that, under physiological conditions, the intrinsic mannose-dependent immunogenicity of FVIII is quenched by endogenous immunochaperones. These data provide a link between the mannosylation of therapeutic self-proteins and their iatrogenic immunogenicity. Such a link would be of special relevance in the context of replacement therapy where mechanisms of central and peripheral tolerance have not been established during ontogeny because of the absence of the antigen.     

Male aging in the Middle Ages: commentaries on the book by Arnau de Vilanova "Conservatio juventute preservatio senectute"

In the Middle Ages medical texts the notes about personal hygiene are scarce and they are dedicated to the Kings or the aristocracy. In his work Regimen sanitatis ad inclytum regen Aragorum, Amaldo de Vilanova underlines six things that are necessary for cleanliness, among which he includes his well-known proposition Conservatio juventute preservatio senectute. We compared his text with those from other authors with references to the issue and, once examined, Vilanova's work stands out. Doctors in the middle ages were already interested in aging and propositions considered today as modern are found described in various works from that period.