Predicting the long-term impact of rotavirus vaccination in 112 countries from 2006 to 2034: A transmission modeling analysis

Rotavirus vaccination has been shown to reduce rotavirus burden in many countries, but the long-term magnitude of vaccine impacts is unclear, particularly in low-income countries. We use a transmission model to estimate the long-term impact of rotavirus vaccination on deaths and disability adjusted life years (DALYs) from 2006 to 2034 for 112 low- and middle-income countries. We also explore the predicted effectiveness of a one- vs two- dose series and the relative contribution of direct vs indirect effects to overall impacts. To validate the model, we compare predicted percent reductions in severe rotavirus cases with the percent reduction in rotavirus positivity among gastroenteritis hospital admissions for 10 countries with pre- and post-vaccine introduction data. We estimate that vaccination would reduce deaths from rotavirus by 49.1 % (95 % UI: 46.6-54.3 %) by 2034 under realistic coverage scenarios, compared to a scenario without vaccination. Most of this benefit is due to direct benefit to vaccinated individuals (explaining 69-97 % of the overall impact), but indirect protection also appears to enhance impacts. We find that a one-dose schedule would only be about 57 % as effective as a two-dose schedule 12 years after vaccine introduction. Our model closely reproduced observed reductions in rotavirus positivity in the first few years after vaccine introduction in select countries. Rotavirus vaccination is likely to have a substantial impact on rotavirus gastroenteritis and its mortality burden. To sustain this benefit, the complete series of doses is needed.

Emerging roles of endoglin/CD105 and angiogenic cytokines for disease development and progression in multiple myeloma patients

Angiogenesis is an essential process for the expansion of multiple myeloma (MM), in which many angiogenic factors participate. Endoglin (CD105) is a transforming growth factor-β co-receptor, being mainly expressed in angiogenic endothelial cells and has been used as a marker of tumor angiogenesis, having prognostic potential. The aim of the study was to evaluate serum levels of soluble CD105 (sCD105) in MM patients, both during diagnosis and after effective conventional chemotherapy, in the plateau phase, and to correlate them with the clinical stage of the disease, as well as with the known angiogenic factors vascular endothelial growth factor, angiogenin and interleukin-18 (IL-18). Serum levels of the aforementioned factors were measured, by enzyme-linked immunosorbent assay, in 56 newly diagnosed MM patients, in 35 of them who entered plateau phase and in 24 healthy controls. Bone marrow aspirations were also performed in all patients to determine plasma cell infiltration. All measured cytokines were higher in MM patients compared with controls and with advancing disease stage (p < 0.001 for all cases). Furthermore, the values of all factors decreased significantly in the plateau phase (p < 0.001 for all cases). Serum levels of sCD105 correlated with the other angiogenic cytokines, whereas only serum levels of angiogenin had prognostic value for the survival. In conclusion, CD105 and the angiogenic cytokines vascular endothelial growth factor, angiogenin and IL-18, seem to have emerging roles both in angiogenesis and tumor growth in MM.

B cell-activating factor: its clinical significance in multiple myeloma patients

B cell-activating factor (BAFF) is a cytokine that plays a major role in the maintenance of normal B-cell development and homeostasis. It has been suggested that in multiple myeloma (MM) it might have regulatory effects on the proliferation and viability of malignant plasma cells. The aim of this study was to evaluate serum levels of BAFF in 52 newly diagnosed MM patients, with varying disease severity, in order to see the correlations between BAFF and indices of MM activity, such as interleukin-6, C-reactive protein, lactate dehydrogenase, and beta-2 microglobulin, and to explore the clinical significance of BAFF in predicting the disease activity of MM. We found increased BAFF serum levels in MM patients, increased in advanced stages, and decreased in plateau phase. We also found significant correlations between BAFF serum levels with the above parameters of disease activity. We conclude that BAFF may play an important role in pathogenesis of MM, could be used as a marker of disease activity, and a possible therapeutic target.

Serum concentrations and clinical significance of soluble CD40 ligand in patients with multiple myeloma

Multiple myeloma (MM) is a disease of plasma cells that express the CD40 receptor. Binding of the CD40 by its natural ligand, CD40 ligand (CD40L), produces growth arrest and/or apoptosis in MM. To evaluate serum levels of soluble CD40L (sCD40L) in MM patients and to correlate them with markers of disease activity and angiogenesis, such as vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), interleukin-6 (IL-6), proliferation marker Ki-67 proliferation index (Ki-67 PI) and bone marrow plasma cell infiltration, fifty-eight MM patients were studied in diagnosis and 43 of them after completion of treatment. Serum levels of sCD40L, VEGF, HGF and IL-6 were measured by ELISA, whereas Ki-67 PI and bone marrow plasma cell infiltration were measured by immunohistochemistry. Pre-treatment levels of sCD40L in MM patients were higher compared to controls and to their levels after effective treatment. Treatment regimen did not affect the degree of reduction of sCD40L levels, whereas patient in partial remission had increased levels compared to those with better response. Significant differences were found among disease stages. There were also positive correlations between CD40L with HGF, VEGF, IL-6 and Ki-67 PI. Elevated serum sCD40L is found in patients with advanced MM stage and can be reduced after effective treatment. Increased levels of this mediator are correlated with angiogenic cytokines, providing evidences that CD40L/CD40 interactions play a significant role in the mechanisms of angiogenesis in MM patients.

Monitoring serum levels ELR+ CXC chemokines and the relationship between microvessel density and angiogenic growth factors in multiple myeloma

BACKGROUND

The ELR+ CXC chemokines are important mediators of tumorigenesis, related to their angiogenic properties. Angiogenesis appears to be a prominent feature in the progression of multiple myeloma (MM). CXC chemokines have four highly conserved cysteine amino acid residues, with the first two cysteine molecules separated by a single amino acid. The angiogenic potential of this group is determined by the presence of three amino acid residues (Glu-Leu-Arg: the ELR motif) preceding the first cysteine amino acid, in the NH2 terminus.

AIMS

The purpose of this study was to determine serum concentrations of angiogenesis-related chemokines ELR+ motif, such as interleukin-8 (IL-8), epithelial neutrophil activating protein-78 (ENA-78) and growth-related gene alpha (GRO-α), as well the bone marrow microvascular density (MVD) in patients with MM at diagnosis and after treatment, in plateau phase. We also evaluated the relationship among them with other known growth factors involved in angiogenesis.

METHODS

Serum levels of the ELR+ CXC chemokines: IL-8, ENA-78 and GRO-α as well as of the angiogenic factors: hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α) were determined in 63 newly diagnosed MM patients, in 30 in plateau phase and in 20 healthy controls. Serum measurements of them were performed with commercially available kits for ELISA. Bone marrow biopsies were performed before and after treatment, in plateau phase, in order to determine MVD by staining vessels with anti-CD31.

RESULTS

Serum concentrations of IL-8, ENA-78, GRO-α and TNF-α were significantly higher in the group of MM patients (44.5±25.3, 765±572.1, 186.5±129.1 and 4.2±2.8 pg/ml, respectively) in comparison to control group (27.3±6.4, 335.1±268.6, 112.5±76.1 and 1.3±0.8 pg/ml) (p<0.02 for GRO-α, p<0.001 for other cases). We also found that untreated patients had higher levels of IL-8, ENA-78, GRO-α than post treatment patients, but statistical significant difference was found only for IL-8 (48.36±30.93 pg/ml vs. 35.05±19.77 pg/ml, p<0.001). Furthermore IL-8, GRO-α, TNF-α, HGF and VEGF were significantly higher with increasing disease stage (p<0.001 in all cases). ENA-78 serum levels were higher in stage III than in stage I and II, but without statistical significance. Additionally we correlated each proinflammatory cytokine with well known angiogenic factors such as HGF, VEGF and TNF-α. A positive correlation was found between serum HGF and IL-8 and GRO-α (r=0.316 p<0.01, r=0.297 p<0.02, respectively). Similarly serum VEGF correlated with ENA-78 and GRO-α (r=0.323 p<0.01, r=0.469 p<0.001, respectively). In the pretreatment group of patients a positive correlation between bone marrow MVD and serum levels of GRO-α was found (r=0.304 p<0.01). There was a difference in survival times between patients with higher than median versus low IL-8, ENA-78 and GRO-α levels, but the differences could not reach statistical significance in either case.

CONCLUSIONS

These findings support the hypothesis that ELR+ motif CXC chemokines, such as IL-8, ENA-78 and GRO-α correlate with angiogenic growth factors and may play a role in the progression of MM. Further studies are needed to determine their prognostic and predictive significance.

[Human African trypanosomiasis: description of two pediatric cases in Yaoundé, Cameroon]

During the first decades of the 20th century, about 45% of deaths in Cameroon were believed to be due to human African trypanosomiasis. Thanks to the screening and treatment campaigns implemented between 1926-1932, a considerable regression of the disease was achieved and, by the 1950s, only a few well-known and delimited foci remained. Today, human African trypanosomiasis is an extremely rare diagnosis, especially in children. The purpose of this report is to describe two cases of neuromeningeal human African trypanosomiasis that were discovered coincidentally in two children, ages 12 and 2 years. The children were from two villages in the center of Cameroon that is not considered as a known endemic focus. These two cases raise difficult questions about the possibility of latent endemic foci of human African trypanosomiasis and of animal-to-human transmission. The outcome was favorable in the first case and fatal in the second.

Levels of soluble forms of ICAM and VCAM in patients with myelodysplastic syndromes and their prognostic significance

The aim of this study was to assess circulating soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and interleukin-1beta (IL-1beta) in myelodysplastic syndromes (MDS) in order to evaluate their clinical significance. Seventy patients with untreated MDS [21 refractory anemia (RA), nine RA with ringed sideroblasts (RARS), 17 RA with excess of blasts (RAEB), 11 RAEB in transformation (RAEBt), and 12 chronic myelomonocytic leukemia (CMML)] were included in this study. Serum levels of sICAM, sVCAM, and IL-1beta were determined at diagnosis using commercially available immunoassays. In addition, 15 healthy volunteers were studied as a control group. sICAM, sVCAM, and IL-1beta serum levels were significantly higher in MDS patients in comparison with the control group (P <0.001). Patients with CMML showed the highest sICAM, sVCAM, and IL-1beta levels in comparison with other MDS-related subtypes. Furthermore significantly elevated levels of the studied parameters were detected in high-risk MDS patients (RAEB, RAEB-t, and CMML) in comparison with low-risk MDS (RA and RARS). IL-1beta was strongly correlated both to sICAM and sVCAM. In conclusion we have provided evidence that increased sICAM and sVCAM serum levels are related to MDS severity.

Relationship between circulating serum soluble interleukin-6 receptor and the angiogenic cytokines basic fibroblast growth factor and vascular endothelial growth factor in multiple myeloma

Angiogenesis plays an important role in multiple myeloma (MM) progression. Various mitogens such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2) have been implicated in the angiogenic process of various malignancies. Interleukin-6 (IL-6) is a growth factor of myeloma cells and its signaling is mediated via a cell surface receptor complex (IL-6r). IL-6 and tumor necrosis factor-alpha (TNF-alpha) are involved in the secretion of VEGF by IL-6r expressing myeloma cells. In this study, serum FGF-2, VEGF, IL-6r, and TNF-alpha were measured in 46 untreated MM patients and were studied in relation to disease stage (by Salmon-Durie criteria) and severity [assessed by serum beta(2)-microglobulin (beta(2)M), C-reactive protein (CRP), alpha(1)-antitrypsin (alpha(1)AT), and lactic dehydrogenase (LDH) levels]. The results showed that FGF-2, VEGF, IL-6r, and TNF-alpha were significantly elevated in MM patients in comparison to controls ( p<0.008) and were significantly higher in stage III disease in comparison to stages I and II ( p<0.03). The mean concentrations of IL-6r were 877+/-374, 1220+/-308, 1431+/-878, and 453+/-180 pg/ml for stages I, II, and III and controls, respectively. Levels of beta(2)M, alpha(1)AT, CRP, and LDH were all significantly higher in MM patients than controls and increased with advancing stage of disease. There were positive correlations of both VEGF and FGF-2 with IL-6r, TNF-alpha, beta(2)M, alpha(1)AT, CRP, and LDH. We conclude that IL-6r and TNF-alpha increase in parallel to VEGF and FGF-2 with increasing stage of MM disease. These molecules correlate with biochemical markers of disease activity and may play a role in the progression of multiple myeloma.