Evaluation of microvascular density in tumors: pro and contra

Microvascular density (MVD) counting protocols have become the morphological gold standard to assess the neovasculature in human tumors. This method requires the use of specific markers to vascular endothelium and of immunohistochemical procedures to visualize microvessels. MVD determined in primary tumors is significantly associated with metastasis and prognosis in several tumors and is most predictive in those tumors that induce significant angiogenesis, namely carcinomas of breast and prostate, and haematological malignancies. There is such a wide range of antibodies and suppliers, antigen retrieval methods, designation of high and low vessel count groups, patient study groups and data interpretation, that it is exceedingly difficult to compare results.     

IL-6 inhibits the tolerogenic function of CD8 alpha+ dendritic cells expressing indoleamine 2,3-dioxygenase.

The outcome of dendritic cell (DC) presentation of tumor and/or self peptides, including P815AB (a tumor peptide of murine mastocytoma cells) and NRP-A7 (a synthetic peptide mimotope recognized by diabetogenic T cells), may depend on a balance between the activities of immunogenic (CD8alpha(-)) and tolerogenic (CD8alpha(+)) DC. By virtue of their respective actions on CD8(-) and CD8(+) DC, IL-12 and IFN-gamma have functionally opposing effects on peptide presentation by the CD8(-) DC subset, and IFN-gamma-activated CD8(+) DC mediate tolerogenic effects that prevail over the adjuvant activity of IL-12 on CD8(-) DC. We have previously shown that CD40 ligation abrogates the tolerogenic potential of CD8(+) DC, an effect associated with an impaired capacity of the CD40-modulated and IFN-gamma-treated DC to degrade tryptophan and initiate T cell apoptosis in vitro. We report here that IL-6 may both replace (upon administration of the recombinant cytokine) and mediate (as assessed by the use of neutralizing Abs) the effect of CD40 ligation in ablating the tolerogenic activity of CD8(+) DC. The activity of IL-6 includes down-regulation of IFN-gammaR expression in the CD8(+) DC subset and correlates to a reduced ability of these cells to metabolize tryptophan and initiate T cell apoptosis in vitro.     

Goat casein genotypes are associated with milk production traits in the Sarda breed

The aim of the current work was to analyze, in the Sarda breed goat, genetic polymorphism within the casein genes and to assess their influence on milk traits. Genetic variants at the CSN1S1, CSN2, CSN1S2 and CSN3 gene loci were investigated using PCR‐based methods, cloning and sequencing. Strong alleles prevailed at the CSN1S1 gene locus and defective alleles also were revealed. Null alleles were evidenced at each calcium‐sensitive gene locus. At the CSN3 gene locus, we observed a prevalence of the CSN3 A and B alleles; the occurrence of rare alleles such as CSN3 B'', C, C', D, E and M; and the CSN3 S allele (GenBank KF644565 ) described here for the first time in Capra hircus. Statistical analysis showed that all genes, except CSN3, significantly influenced milk traits. The CSN1S1 BB and AB genotypes were associated with the highest percentages of protein (4.41 and 4.40 respectively) and fat (5.26 and 5.34 respectively) (P < 0.001). A relevant finding was that CSN2 and CSN1S2 genotypes affected milk protein content and yield. The polymorphism of the CSN2 gene affected milk protein percentage with the highest values recorded in the CSN2 AA goats (4.35, at P < 0.001). The CSN1S2 AC goats provided the highest fat (51.02 g/day) and protein (41.42 g/day) (P < 0.01) production. This information can be incorporated into selection schemes for the Sarda breed goat.     

Regulation of autophagy by polyphenols: Paving the road for treatment of neurodegeneration

In the present paper, we will discuss on the importance of autophagy in the central nervous system, and outline the relation between autophagic pathways and the pathogenesis of neurodegenerative disorders. The potential therapeutic benefits of naturally occurring phytochemicals as pharmacological modulators of autophagy will also be addressed. Our findings provide renewed insight on the molecular modes of protection by polyphenols, which is likely to be at least in part mediated not only by their potent antioxidant and anti-inflammatory effects, but also through modulation of autophagic processes to remove the aberrant protein aggregates.     

Amiloride does not alter NaCl avoidance in Fischer-344 rats

Fischer-344 (F-344) rats differ from other common rat strains in that they fail to show any preference for NaCl at any concentration in two- bottle preference tests. Because 100 microM amiloride partially blocks the NaCl-evoked chorda tympani (CT) response in electrophysiological studies, we tested NaCl preference (0.068-0.273 M) in F-344 rats with and without 100 microM amiloride solution as the solvent. A third group was tested with unadulterated NaCl solutions following CT transection. Amiloride had no significant effect on the NaCl preference-aversion function, whereas CT transection significantly reduced NaCl avoidance. These results suggest that the amiloride-sensitive component of the NaCl response is not necessary for F-344 rats to display avoidance of NaCl, but the entire CT input is.      

In the early phase of programmed cell death in Tobacco Bright Yellow 2 cells the mitochondrial adenine nucleotide translocator, adenylate kinase and nucleoside diphosphate kinase are impaired in a reactive oxygen species-dependent manner

To investigate whether and how mitochondria can change in plant programmed cell death (PCD), we used the non-photosynthetic Tobacco Bright Yellow 2 (TBY-2) cells. These can be synchronized to high levels, stand out in terms of growth rate and homogeneity and undergo PCD as a result of heat shock. Using these cells we investigated the activity of certain mitochondrial proteins that have a role in providing ATP and/or other nucleoside triphosphates (NTPs). We show that, already after 2 h from the heat shock, when cell viability remains unaffected, the rate of ADP/ATP exchange due to adenine nucleotide translocator (ANT) activity, and the rate of the reactions catalysed by adenylate kinase (ADK; EC 2.7.4.3) and nucleoside diphosphate kinase (NDPK; EC 2.7.4.6) are inhibited in a non-competitive-like manner. In all cases, externally added ascorbate partially prevented the inhibition. These effects occurred in spite of minor (for ANT) or no changes in the mitochondrial protein levels as immunologically investigated. Interestingly, a decrease of both the steady state level of the ascorbate pool and of the activity of l-galactono-gamma-lactone dehydrogenase (GLDH) (EC 1.3.2.3), the mitochondrial enzyme catalysing the last step of ascorbate biosynthesis, were also found.     

Coronary effects of cyclovirobuxine D in anesthetized pigs and in isolated porcine coronary arteries.

The present study was undertaken in anesthetized pigs and in isolated porcine coronary arteries to determine the primary coronary effects of cyclovirobuxine D. In six pigs, the intravenous administration of 1.5 mg/kg of cyclovirobuxine D whilst preventing changes in heart rate and aortic blood pressure caused increases in left ventricular dP/dtmax and coronary blood flow which respectively averaged 10% and 23.9%. These responses were progressively augmented by graded increases in the dose of the drug (four pigs) and were not affected by blockade of cholinergic and adrenergic receptors (five pigs). Intravenous blockade of nitric oxide synthase (L-NAME, five pigs) abolished both responses, while intracoronary injection of L-NAME (five pigs) abolished only the coronary vasodilatation. In ten isolated coronary segments, cyclovirobuxine D significantly reduced the degree of potassium chloride-induced contraction. This reduction was not affected by inhibition of cyclooxygenase with indomethacin (five segments) or potassium channels blockade with glibenclamide (five segments), but it was abolished by L-NAME (five segments) or removal of endothelium (five segments). The present study showed that cyclovirobuxine D caused a primary effect of coronary vasodilatation, which involved mechanisms related to the endothelial release of nitric oxide.     

Molecular biodiversity of cassava begomoviruses in Tanzania: evolution of cassava geminiviruses in Africa and evidence for East Africa being a center of diversity of cassava geminiviruses

Cassava is infected by numerous geminiviruses in Africa and India that cause devastating losses to poor farmers. We here describe the molecular diversity of seven representative cassava mosaic geminiviruses (CMGs) infecting cassava from multiple locations in Tanzania. We report for the first time the presence of two isolates in East Africa: (EACMCV-[TZ1] and EACMCV-[TZ7]) of the species East African cassava mosaic Cameroon virus, originally described in West Africa. The complete nucleotide sequence of EACMCV-[TZ1] DNA-A and DNA-B components shared a high overall sequence identity to EACMCV-[CM] components (92% and 84%). The EACMCV-[TZ1] and -[TZ7] genomic components have recombinations in the same genome regions reported in EACMCV-[CM], but they also have additional recombinations in both components. Evidence from sequence analysis suggests that the two strains have the same ancient origin and are not recent introductions. EACMCV-[TZ1] occurred widely in the southern part of the country. Four other CMG isolates were identified: two were close to the EACMV-Kenya strain (named EACMV-[KE/TZT] and EACMV-[KE/TZM] with 96% sequence identity); one isolate, TZ10, had 98% homology to EACMV-UG2Svr and was named EACMV-UG2 [TZ10]; and finally one isolate was 95% identical to EACMV-[TZ] and named EACMV-[TZ/YV]. One isolate of African cassava mosaic virus with 97% sequence identity with other isolates of ACMV was named ACMV-[TZ]. It represents the first ACMV isolate from Tanzania to be sequenced. The molecular variability of CMGs was also evaluated using partial B component nucleotide sequences of 13 EACMV isolates from Tanzania. Using the sequences of all CMGs currently available, we have shown the presence of a number of putative recombination fragments that are more prominent in all components of EACMV than in ACMV. This new knowledge about the molecular CMG diversity in East Africa, and in Tanzania in particular, has led us to hypothesize about the probable importance of this part of Africa as a source of diversity and evolutionary change both during the early stages of the relationship between CMGs and cassava and in more recent times. The existence of multiple CMG isolates with high DNA genome diversity in Tanzania and the molecular forces behind this diversity pose a threat to cassava production throughout the African continent.