Pathological implications of cellular stress in cardiovascular diseases.

Cellular stress has been a key factor in the development of cardiovascular diseases. Major types of cellular stress such as mitochondrial stress, endoplasmic reticulum stress, hypoxia, and replicative stress have been implicated in clinical complications of cardiac patients. The heart is the central regulator of the body by supplying oxygenated blood throughout the system. Impairment of cellular function could lead to heart failure, myocardial infarction, ischemia, and even stroke. Understanding the effect of these distinct types of cellular stress on cardiac function is crucial for the scientific community to understand and develop novel therapeutic approaches. This review will comprehensively explain the different mechanisms of cellular stress and the most recent findings related to stress-induced cardiac dysfunction.

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.

[Serum procalcitonin: a reliable tool for the diagnosis and follow-up of neonatal bacterial infections in Sub-Saharan Africa]. / Intérêt du dosage de la procalcitonine sérique dans le diagnostic et le suivi des infections néonatales d'origine bactérienne à Yaoundé, Cameroun.

BACKGROUND AND AIM: Neonatal infection (NNI) is a public health problem in developing countries where pediatricians and specifically neonatologists encounter many diagnostic difficulties. Having a precise and easily measurable biological marker, with a high sensitivity and a high negative predictive value, that can rapidly detect NNI, remains a great challenge. The aim of this study was to determine the place of serum procalcitonin (PCT) in the diagnosis and follow-up of bacterial NNI in resource-limited contexts. METHODS: We carried out a cross-sectional study from October 2009 to February 2010 at the Mother and Child Centre of the Chantal Biya Foundation, Cameroon. We included all neonates born at term, suspected of NNI, and hospitalized in the Neonatal Care Unit of the aforementioned centre during the study period. We measured PCT levels at entry and 48h later, and determined its sensitivity, specificity, and positive and negative predictive values. RESULTS: Twenty-five out of the 98 neonates enrolled presented with a confirmed diagnosis of NNI. PCT was positive in 92.4% of cases. Contrariwise, serum C-reactive protein was positive in 84.6% of patients with a cut-off point at 6mg/L, and remained positive in only 38.4% of cases when the cut-off point was raised to 20mg/L. The sensitivity, specificity, and positive and negative predictive values of PCT were 96.0%, 77.7%, 85.3%, and 93.3%, respectively. Six deaths were recorded, five of which exhibited very high PCT levels (≥10ng/mL). All neonates with negative PCT levels had a good clinical outcome as none of them died. If PCT were to be considered as a diagnostic tool of NNI, only 43 (43.9%) neonates would have benefited from a justified antibiotic therapy exceeding 48h, with a significant reduction in duration of hospitalization (9.1±3.3 vs 5.1±4.6 days; P<0.05). CONCLUSION: PCT may be an early and reliable indicator of bacterial NNI. Its course throughout hospitalization may reflect the therapeutic response, and elevated levels of PCT may be highly suggestive of a poor clinical prognosis. PCT could therefore serve as a useful tool for the screening, diagnosis, and follow-up of neonates suspected of bacterial NNI in resource-poor settings.

Circulating serum levels of IL-20 in multiple myeloma patients: its significance in angiogenesis and disease activity.

Angiogenesis is an important hallmark in multiple myeloma (MM) pathogenesis, with the participation of various versatile molecules. Interleukin-20 (IL-20) is a pro-inflammatory cytokine with diverse angiogenic properties. Our purpose was to estimate the possible impact of IL-20 on MM angiogenesis and disease activity. We measured serum levels of IL-20 along with levels of vascular endothelial growth factor (VEGF), basic-fibroblast growth factor and angiopoietin 2 in 58 active MM myeloma patients, in 32 of them who responded to bortezomib-based therapy and in 20 controls. We also measured bone marrow microvasclular density (MVD) by immunohistochemical method. Serum levels of all cytokines and bone marrow MVD were higher in active MM patients compared to controls and responders to bortezomib-based therapy (p < 0.001 in all cases). They were also in parallel with International Staging System stages (p < 0.001 for all cases). Serum levels of IL-20 correlated positively with levels of angiogenic cytokines and bone marrow MVD (p < 0.01 for MVD, p < 0.002 for VEGF and p < 0.001 for the other cases). Our results strongly suggest that serum IL-20 concentrations participate actively in the pathophysiology of MM progression. Therefore, it could be used as an indicator of the disease progression and angiogenesis processes.

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-ß 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]. / Trypanosomiase humaine africaine: à propos de deux cas pédiatriques à Yaoundé, Cameroun.

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.

Veno-occlusive disease of the liver associated with chronic myelomonocytic leukemia treated with vincristine and standard doses of cytarabine.

A unique case of a 72-year-old man with chronic myelomonocytic leukemia (CMML) who developed hepatic veno-occlusive disease (VOD) after treatment with a single dose of vincristine and standard doses of cytarabine is described. Unexpected peroneal nerve palsy suggestive of vincristine neurotoxicity occurred concurrently and pointed to vincristine as the most likely cause of the VOD. To the best of our knowledge, association between vincristine and hepatic VOD has not been previously described in chemotherapy-naive patients with CMML.

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.