Serological Cross Reactivity between Zika and Dengue Viruses in Experimentally Infected Monkeys

正Dear Editor,Zika virus(ZIKV),a pathogen within the genus Flavivirus,family Flaviviridae brought an international public health emergency due to its association with neonatal microcephaly case(Platt and Miner 2017).Currently the most reliable diagnostic test is PCR detection of ZIKV RNA from body fluid samples.Unfortunately,the short viremia window and asymptomatic/mild infections greatly reduce the success rate of PCRs(de Vasconcelos et al.2018).     

Influence of Feeding Inorganic Vanadium on Growth Performance,Endocrine Variables and Biomarkers of Bone Health in Crossbred Calves

The nutritional essentialities of transition element vanadium (V) as micro-nutrient in farm animals have not yet been established, though in rat model, vanadium as vanadate has been reported to exert insulin-mimetic effect and shown to be needed for proper development of bones. The objective of this study was to determine the effect of V supplementation on growth performance, plasma hormones and bone health status in calves. Twenty-four crossbred calves (body weight 72.83 ± 2.5 kg; age 3–9 months) were blocked in four groups and randomly assigned to four treatment groups (n = 6) on body weight and age basis. Experimental animals were kept on similar feeding regimen except that different groups were supplemented with either 0, 3, 6 or 9 ppm inorganic V/kg DM. Effect of supplementation during 150-day experimental period was observed on feed intake, body weight gain, feed efficiency, body measures, endocrine variables, plasma glucose and biomarkers of bone health status. Supplementation of V did not change average daily gain (ADG), dry matter intake (DMI), feed efficiency and body measures during the experimental period. During the post-V supplementation period plasma insulin-like growth factor-1 (IGF-1), triiodothyronine (T₃) and thyroxin (T₄) concentrations were increased and observed highest in 9 mg V/kg DM fed calves; however, levels of insulin, glucose, parathyroid hormone (PTH) and calcitonin hormones remained similar among calves fed on basal or V-supplemented diets. Bone alkaline phosphatase (Bone-ALP) concentration was increased (P < 0.05); however, plasma protein tyrosine phosphatase (PTP) level decreased (P < 0.05) in 6 and 9 mg V/kg DM supplemented groups. Plasma hydroxyproline (Hyp) and tartrate-resistant acid phosphatase (TRAP) concentration were unchanged by V supplementation. Blood V concentration showed positive correlation with supplemental V levels. These results suggest that V may play a role in modulation of the action of certain endocrine variables and biomarkers of bone health status in growing crossbred calves.     

Interaction of melanin with proteins--the importance of an acidic intramelanosomal pH.

Melanin is a highly irregular heteropolymer consisting of monomeric units derived from the enzymatic oxidation of the amino acid tyrosine. The process of melanin formation takes place in specialized acidic organelles (melanosomes) in melanocytes. The process of melanin polymerization requires an alkaline pH in vitro, and therefore, the purpose of an acidic environment in vivo remains a mystery. It is known that melanin is always bound to protein in vivo. It is also seen that polymerization in vitro at an acidic pH necessarily requires the presence of proteins. The effect of various model proteins on melanin synthesis and their interaction with melanin was studied. It was seen that many proteins could increase melanin synthesis at an acidic pH, and that different proteins resulted in the formation of different states of melanin, i.e., a precipitate or a soluble, protein-bound form. We also present evidence to show that soluble protein-bound melanin is present in vivo (in B16 cells as well as in B16 melanoma tissue). An acidic pH appeared to be necessary to ensure the formation of a uniform, very high molecular weight melano-protein complex. The interaction between melanin and proteins appears to be largely charge-dependent as evidenced by zeta potential measurements, and this interaction is also increased in an acidic pH. Thus, it appears that an acidic intramelanosomal pH is essential to ensure maximum interaction between protein and melanin, and also to ensure that all the melanin formed is protein-bound.     

Superficial Temporal Artery Bypass in Occlusive Cerebral Vascular Disease

In carefully selected cases, superficial temporal artery bypass appears to be a promising and useful method for bringing about an improved collateral supply in problems of occlusive cerebral vascular disease. Such a procedure appears to improve the quality of life.     

Dendritic cells post-maturation are reprogrammed with heightened IFN-gamma and IL-10

Mature dendritic cells (mDCs) undergo "exhaustion" in producing cytokines. Nevertheless, whether this "exhaustion" of mDCs is selective to certain cytokines, or whether mDCs have specific cytokine-producing profiles has yet to be defined. Herein, we investigated the cytokine production in vitro by immature DCs (iDCs) and LPS-induced mDCs. Compared to iDCs, mDCs produced comparable levels of IL-6 and TNF-alpha. Strikingly, mDCs produced significantly higher IFN-gamma and IL-10. IL-12 production of mDCs was suppressed. Kinetic studies of the responses of iDCs and mDCs to LPS or CD40L showed that mDCs acquired progressively heightened activity in producing IFN-gamma and IL-10. TNF-alpha-, IL-6-producing capability of mDCs was maintained. Nevertheless, IL-12 production by mDCs was not recovered at any time point. Mature DCs were potent in priming both Th1 and Th2 cells. In conclusion, upon maturation, DCs are reprogrammed with a distinct cytokine-secreting profile, which may play an important role in regulating T cell functions.     

Dihedral angle preferences of amino acid residues forming various non-local interactions in proteins

In theory, a polypeptide chain can adopt a vast number of conformations, each corresponding to a set of backbone rotation angles. Many of these conformations are excluded due to steric overlaps. Ramachandran and coworkers were the first to look into this problem by plotting backbone dihedral angles in a two-dimensional plot. The conformational space in the Ramachandran map is further refined by considering the energetic contributions of various non-bonded interactions. Alternatively, the conformation adopted by a polypeptide chain may also be examined by investigating interactions between the residues. Since the Ramachandran map essentially focuses on local interactions (residues closer in sequence), out of interest, we have analyzed the dihedral angle preferences of residues that make non-local interactions (residues far away in sequence and closer in space) in the folded structures of proteins. The non-local interactions have been grouped into different types such as hydrogen bond, van der Waals interactions between hydrophobic groups, ion pairs (salt bridges), and ππ-stacking interactions. The results show the propensity of amino acid residues in proteins forming local and non-local interactions. Our results point to the vital role of different types of non-local interactions and their effect on dihedral angles in forming secondary and tertiary structural elements to adopt their native fold.