New approaches to the prevention and eradication of rabies

Despite significant progress in improving the pre- and postexposure prophylaxis of human rabies, the development of better and more cost-effective vaccines and antiviral therapeutics remains a major goal for the treatment of human rabies, the control of animal rabies and particularly for the eradication of rabies virus reservoirs in terrestrial wildlife. In this review, we discuss the structural requirements for an effective rabies vaccine, as well as new strategies currently in use for the development of safer and more potent rabies vaccines for rabies prophylaxis and eradication. Finally, we discuss new immune therapeutics aimed at replacing the conventional administration of antirabies immunoglobulin used in rabies post-exposure prophylaxis in humans.     

Identification of viral genomic elements responsible for rabies virus neuroinvasiveness

Attenuated tissue culture-adapted and natural street rabies virus (RV) strains differ greatly in their neuroinvasiveness. To identify the elements responsible for the ability of an RV to enter the CNS from a peripheral site and to cause lethal neurological disease, we constructed a full-length cDNA clone of silver-haired bat-associated RV (SHBRV) strain 18 and exchanged the genes encoding RV proteins and genomic sequences of this highly neuroinvasive RV strain with those of a highly attenuated nonneuroinvasive RV vaccine strain (SN0). Analysis of the recombinant RV (SB0), which was recovered from SHBRV-18 cDNA, indicated that this RV is phenotypically indistinguishable from WT SHBRV-18. Characterization of the chimeric viruses revealed that in addition to the RV glycoprotein, which plays a predominant role in the ability of an RV to invade the CNS from a peripheral site, viral elements such as the trailer sequence, the RV polymerase, and the pseudogene contribute to RV neuroinvasiveness. Analyses also revealed that neuroinvasiveness of an RV correlates inversely with the time necessary for internalization of RV virions and with the capacity of the virus to grow in neuroblastoma cells.     

Elevated hemoglobin concentration in 3 children with HFE mutation

Aim

The aim of the study was to analyse the reason of elevated hemoglobin concentration in childhood.

Background

Elevated hemoglobin concentration is a rare abnormality during childhood. There are disorders of hereditary or acquired hyperproliferations of red cells or pseudo high hemoglobin conditions.

Materials and methods

We present 3 asymptomatic children in whom high hemoglobin concentration was diagnosed by a family doctor.

Results

Given that the iron concentration was elevated, genetic testing for HFE mutation was carried out.

Conclusion

Patients presented with HFE mutation might have an increased hemoglobin production.     

Intracoronary Near-Infrared Spectroscopy (NIRS) Imaging for Detection of Lipid Content of Coronary Plaques: Current Experience and Future Perspectives

Acute coronary syndromes are frequently caused by “vulnerable” coronary plaques with a lipid-rich core. In 1993 near-infrared spectroscopy (NIRS) was first used to detect the lipid (cholesterol) content of atherosclerotic plaques in an experimental animal study. NIRS was then carefully validated using human atherosclerotic plaques (ex vivo), and has subsequently been developed for intracoronary imaging in humans, for which now an FDA-approved catheter-based NIRS system is available. NIRS provides a “chemogram” of the coronary artery wall and is used to detect lipid-rich plaques. Using this technology, recent studies have shown that lipid-rich plaques are very frequent in the culprit lesion of patients with an acute coronary syndrome, and are also common in non-culprit coronary lesions in these patients as compared to patients with stable coronary disease. First studies are evaluating the impact of statin therapy on coronary NIRS-detected lipid cores. Intracoronary NIRS imaging represents a highly interesting method for coronary plaque characterization in humans and may become a valuable tool for the development of novel therapies aiming to impact on the biology of human coronary artery plaques, likely in combination with other intracoronary imaging techniques, such as optical coherence tomography.     

In vitro growth and stability of recombinant rabies viruses designed for vaccination of wildlife

Three live rabies virus (RV) recombinant vaccine candidates, SPBNGA, SPBNGA-Cyto c (+), and SPBNGA-GA, were examined for their production levels and stability. Maximum production levels up to 10(10) infectious particles/mL were achieved using bioreactor technology. All virus lots exhibited thermostability profiles typical for RV vaccines and were non-pathogenic for intracranially inoculated immunocompetent mice. Moreover, sequence analysis indicated high genetic stability in all three RVs during 10 consecutive passages in newborn mice. This analysis revealed no change in the extra RV G gene in the SPBNGA-GA vaccine or in the cytochrome c gene in the SPBNGA-Cyto c (+) vaccine. Moreover, no changes were detected in the G gene codon for Glu333, which renders the virus non-pathogenic. However, after the fifth passage, a mutation resulting in an Asn194 --> Lys194 exchange emerged in the G genes of all three RVs. This mutation was associated with a modest increase in pathogenicity in SPBNGA and SPBNGA-Cyto c (+), but not in SPBNGA-GA, which contained the mutation in only one of its two G genes and which remained non-pathogenic. These results demonstrate the feasibility of producing RV vaccines that remain highly stable even after multiple passages.     

Acute metabolic responses to a 24-h ultra-marathon race in male amateur runners

The study was conducted to evaluate the metabolic responses to a 24 h ultra-endurance race in male runners. Paired venous and capillary blood samples from 14 athletes (mean age 43.0 ± 10.8 years, body weight 64.3 ± 7.2 kg, VO_2max 57.8 ± 6.1 ml kg⁻¹ min⁻¹), taken 3 h before the run, after completing the marathon distance (42.195 km), after 12 h, and at the finish of the race, were analyzed for blood morphology, acid–base balance and electrolytes, lipid profile, interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP), and serum enzyme activities. Mean distance covered during the race was 168.5 ± 23.1 km (range 125.2–218.5 km). Prolonged ultra-endurance exercise triggered immune and inflammatory responses, as evidenced by a twofold increase in total leukocyte count with neutrophils and monocytes as main contributors, nearly 30-fold increase in serum IL-6 and over 20-fold rise in hsCRP. A progressive exponential increase in mean creatine kinase activity up to the level 70-fold higher than the respective pre-race value, a several fold rise in serum activities of aspartate aminotransferase and alanine aminotransferase, and a fairly stable serum γ-glutamyl transferase level, were indicative of muscle, but not of liver damage. With duration of exercise, there was a progressive development of hyperventilation-induced hypocapnic alkalosis, and a marked alteration in substrate utilization towards fat oxidation to maintain blood glucose homeostasis. The results of this study may imply that progressive decline in partial CO₂ pressure (hypocapnia) that develops during prolonged exercise may contribute to increased interleukin-6 production.     

Thrombin generation in chronic obstructive pulmonary disease: dependence on plasma factor composition

Background

Chronic obstructive pulmonary disease (COPD) is associated with an increased risk for thromboembolic events. We investigated thrombin generation profiles in COPD patients and their dependence on plasma factor/inhibitor composition.

Methods

Factors (f) (fII, fV, fVII, fVIII, fIX, fX), antithrombin, protein C (PC) and free tissue factor pathway inhibitor (fTFPI) from 60 COPD patients (aged 64.2 ± 10.1 years; a mean forced expiratory volume in 1 second [FEV₁], 55.6 ± 15.8% of predicted values) were compared with those for 43 controls matched for age, sex, weight and smoking. Patients receiving anticoagulation were excluded. Using each individual's plasma coagulation protein composition, tissue factor-initiated thrombin generation was assessed computationally.

Results

COPD patients had higher fII (115 ± 16 vs 102 ± 10%, p < 0.0001), fV (114 ± 19 vs 102 ± 12%, p = 0.0002), fVII (111 ± 15 vs 102 ± 17%, p = 0.002), fVIII (170 ± 34 vs 115 ± 27%, p < 0.0001), and fIX (119 ± 21 vs 107 ± 17%, p = 0.003), and lower fTFPI (17.7 ± 3.2 vs 18.9 ± 3.2 ng/ml, p = 0.047) compared with controls, while fX, antithrombin, and PC were similar in both groups. Computational thrombin generation profiles showed that compared with controls, COPD patients had higher maximum thrombin levels (+ 28.3%, p < 0.0001), rates of thrombin generation (+ 46.1%, p < 0.0001) and total thrombin formation (+ 14.4%, p < 0.001), together with shorter initiation phase of thrombin generation (p < 0.0001) and the time to maximum thrombin levels (p < 0.0001). Thrombin generation profiles in COPD patients can be normalized via correction of fII, fVIII , fIX and TFPI. The severity of COPD and inflammatory markers were not associated with thrombin generation profiles.

Conclusions

Prothrombotic phenotype in COPD patients is largely driven by increased prothrombin, fVIII, fIX, and lower fTFPI.     

Effective preexposure and postexposure prophylaxis of rabies with a highly attenuated recombinant rabies virus

Rabies remains an important public health problem with more than 95% of all human rabies cases caused by exposure to rabid dogs in areas where effective, inexpensive vaccines are unavailable. Because of their ability to induce strong innate and adaptive immune responses capable of clearing the infection from the CNS after a single immunization, live-attenuated rabies virus (RV) vaccines could be particularly useful not only for the global eradication of canine rabies but also for late-stage rabies postexposure prophylaxis of humans. To overcome concerns regarding the safety of live-attenuated RV vaccines, we developed the highly attenuated triple RV G variant, SPBAANGAS-GAS-GAS. In contrast to most attenuated recombinant RVs generated thus far, SPBAANGAS-GAS-GAS is completely nonpathogenic after intracranial infection of mice that are either developmentally immunocompromised (e.g., 5-day-old mice) or have inherited deficits in immune function (e.g., antibody production or type I IFN signaling), as well as normal adult animals. In addition, SPBAANGAS-GAS-GAS induces immune mechanisms capable of containing a CNS infection with pathogenic RV, thereby preventing lethal rabies encephalopathy. The lack of pathogenicity together with excellent immunogenicity and the capacity to deliver immune effectors to CNS tissues makes SPBAANGAS-GAS-GAS a promising vaccine candidate for both the preexposure and postexposure prophylaxis of rabies.     

SOX-2, but not Oct4, is highly expressed in early-stage endometrial adenocarcinoma and is related to tumour grading

Background: Expression of SOX-2 and Oct4 as markers for the identification of cancer stem cells (CSCs) has been revealed in several malignancies. In this study, the co-expression of SOX-2 and Oct4 and their correlation with clinicopathological features of endometrial adenocarcinomas (EACs) was investigated. Methods: SOX-2 and Oct4 expression was assessed by immunohistochemistry in 27 (39.13%) stage IA and in 42 (60.87%) stage IB International Federation of Gynaecology and Obstetrics (FIGO) EACs and related to the clinicopathological features of patients. Results: The expression of SOX-2 was confirmed in 62/69 tumour specimens compared to Oct4 expression in 46/69 specimens (P = 0.015) and no difference in median staining intensity between SOX-2 and Oct-4 was observed. The highest median SOX-2 expression was found in high-grade (G3) EAC samples compared to moderate-grade (G2) EAC specimens (P = 0.020) and low-grade (G1) specimens (P = 0.008), while no differences in median Oct4 expression in EAC samples according to grading were present. In G3 specimens, significantly higher median SOX-2 expression was noted compared to Oct4 (P = 0.002). SOX-2 and Oct4 co-expression was observed only in G1 EAC (R: 0.51; P = 0.031). Age of EAC diagnosis was positively correlated with SOX-2 expression (b = 0.193; R² = 10.83%; P = 0.003) but not to age of menarche, menopause, parity or body mass index. Conclusions: There is no need to use SOX-2 expression as a poor outcome predictor in stage I EAC, and SOX-2 expression should be analysed in more advanced stages.