Synthesis and Antiviral Activity of 5′-O-Sulfamoyluridine Derivatives

Abstract

A series of 5′-O-[[[[(alkyl)oxy]carbonyl] amino] sulfonyl] uridines have been synthesized by reaction of cyclohexanol, palmityl alcohol, 1,2-di-O-benzoylpropanetriol and 2,3,4,6-tetra-O-benzoyl-L-glucopyranose with chlorosulfonyl isocyanate and 2,3′-O-isopropylidene-uridine. Another series of 5′-O-(N-ethyl and N-isopropylsulfamoyl) uridines have been prepared by reaction of 2′,3′-O-isopropylidene and 2′,3′-di-O-acetyluridine with N-ethylsulfamoyl and N-isopropylsulfamoyl chlorides. All compounds were tested against HSV-2, VV, SV and ASFV viruses. 2′,3′-Di-O-acetyl-5′-O-(N-ethyl and N-isopropylsulfamoyl) uridine showed significant activities against HSV-2. 5′-O-[[[[(2,3,4,6-Tetra-O-benzoyl-β-L-glucopyranosyl)oxy]carbonyl]amino] sulfonyl]-2′,3′-O-isopropylideneuridine was very active against ASFV.     

Bladder Cancer After Radiotherapy for Prostate Cancer

External beam radiotherapy (EBRT) is frequently used in the management of prostate cancer (PCa) as definitive, postoperative, or salvage local treatment. Although EBRT plays a central role in the management of PCa, complications remain a troubling by-product. Several studies have demonstrated an association between radiotherapy and elevated risk of acute and late toxicities. A secondary malignancy induced by initial therapy represents one of the most serious complications related to definitive cancer treatment. The radiation-related secondary primary malignancy risk increases with increasing survival time. Transitional cell carcinoma of the bladder is the most frequent secondary primary malignancy occurring after radiotherapy and is described as more aggressive; it may be diagnosed later because some radiation oncologists believe that the hematuria that occurs after prostate EBRT is normal. Some patients treated for localized PCa will subsequently develop invasive bladder cancer requiring surgical intervention. Patients with PCa treated with EBRT should be monitored closely for the presence of bladder cancer.Key words: Bladder cancer, Prostate cancer, Radiotherapy, External beam radiotherapyThe phenomenon of radiation-inducing the carcinogenesis has been well described in literature for decades. The correlation between ionizing radiation and DNA damage has been discussed in several studies.^1–4 Most of these studies evaluated the growth of solid tumors in a large population exposed to moderate to heavy doses of radiation, such as factory workers, patients exposed to a large number of diagnostic radiographic studies, and survivors of atomic and nuclear explosions. ¹ The casual effects of radiation exposure with subsequent mutagenesis are quite clear, shown both in vivo and in vitro.² Previous radiotherapy (RT) for prostate cancer (PCa) may play an important role in the development of secondary primary bladder cancer. This is a fairly uncommon event but a very real entity, of which both urologists and radiation oncologists need to be aware.     

Scaling-up of a B-phycoerythrin production and purification bioprocess involving aqueous two-phase systems: Practical experiences

One of the most attractive segments in food and cosmetic industries is that of natural pigments. Since some synthetic pigments have been reported to be hazardous for humans, natural pigments obtained through biotechnological processes represent an attractive alternative. Our research group has previously worked on the development of an aqueous two-phase system (ATPS)-based prototype process for the recovery of B-phycoerythrin (BPE), a natural high-value pigment obtained from Porphyridium cruentum. Detailed studies describing the scaling up of ATPS processes from bench scale to pilot plant facilities are not common. In this paper experiences derived from the scale-up of a previously developed process for production and recovery of highly purified (purity defined as the absorbance ratio A₅₄₅/A₂₈₀ > 4) BPE are described, where a scale-up factor of 850× was implemented. Characterization of cell disruption with a pilot-scale bead mill allowed efficient BPE release at 2900 rpm, 10% (w/v) sample load, 60% (v/v) bead load and 0.5 mm glass beads and 22 min of residence time with a yield of 1.35 mg BPE/g of wet biomass. BPE was recovered and purified using a strategy comprising isoelectric precipitation, aqueous two-phase fractionation and ultrafiltration. A 54% global BPE recovery yield, with final purity of 4.1, was achieved under optimal process conditions. Considering total costs for raw materials and energy expenditures for one batch, it was determined that the production cost of BPE was of $1.17 USD/mg, which is underneath the commercial price of a BPE standard (>$30 USD/mg).     

Environmental gradients shift the direction of the relationship between native and alien plant species richness

Aim

To assess how environmental, biotic and anthropogenic factors shape native–alien plant species richness relationships across a heterogeneous landscape.

Location

Banks Peninsula, New Zealand.

Methods

We integrated a comprehensive floristic survey of over 1200 systematically located 6 × 6 m plots, with corresponding climate, environmental and anthropogenic data. General linear models examined variation in native and alien plant species richness across the entire landscape, between native‐ and alien‐dominated plots, and within separate elevational bands.

Results

Across all plots, there was a significant negative correlation between native and alien species richness, but this relationship differed within subsets of the data: the correlation was positive in alien‐dominated plots but negative in native‐dominated plots. Within separate elevational bands, native and alien species richness were positively correlated at lower elevations, but negatively correlated at higher elevations. Alien species richness tended to be high across the elevation gradient but peaked in warmer, mid‐ to low‐elevation sites, while native species richness increased linearly with elevation. The negative relationship between native and alien species richness in native‐dominated communities reflected a land‐use gradient with low native and high alien richness in more heavily modified native‐dominated vegetation. In contrast, native and alien richness were positively correlated in very heavily modified alien‐dominated plots, most likely due to covariation along a gradient of management intensity.

Main conclusions

Both positive and negative native–alien richness relationships can occur across the same landscape, depending on the plant community and the underlying human and environmental gradients examined. Human habitat modification, which is often confounded with environmental variation, can result in high alien and low native species richness in areas still dominated by native species. In the most heavily human modified areas, dominated by alien species, both native and alien species may be responding to similar underlying gradients.

     

Biology and ecology of Brazilian elodea (Egeria densa) and its specific herbivore, Hydrellia sp., in Argentina

Egeria densa (Hydrocharitaceae) is a submerged macrophyte from South America that is a weed in several countries. It crowds out native plants and hinders water use, causing economic and environmental damage. The leafminer fly Hydrellia sp. 1 (Diptera: Ephydridae), was found feeding in E. densa throughout its Argentine distribution, and is currently the only known specialist herbivore of E. densa. It was reared in the laboratory and tested on 25 plant species. This herbivore can cause heavy defoliation in the laboratory and in the field. Hydrellia sp. 1 was found only on E. densa, but in the laboratory it also developed on two other Hydrocharitaceae species in the same family; Egeria naias, and Elodea callitrichoides. Significant oviposition and feeding were only observed on its primary natural host, and to a lesser degree on E. naias. Field studies indicate Hydrellia sp. 1 is present in the field year round, unless the host plant is prostrate for long periods, or covered by floating macrophytes. These results indicate Hydrellia sp. 1 may be a suitable biocontrol candidate for E. densa.     

Fetal mesenchymal stromal cells from cryopreserved human chorionic villi: cytogenetic and molecular analysis of genome stability in long-term cultures

Background aimsFirst-trimester chorionic villi (CV) are an attractive source of human mesenchymal stromal cells (hMSC) for possible applications in cellular therapy and regenerative medicine. Human MSC from CV were monitored for genetic stability in long-term cultures.MethodsWe set up a good manufacturing practice cryopreservation procedure for small amounts of native CV samples. After isolation, hMSC were in vitro cultured and analyzed for biological end points. Genome stability at different passages of expansion was explored by karyotype, genome-wide array-comparative genomic hybridization and microsatellite genotyping.ResultsGrowth curve analysis revealed a high proliferative potential of CV-derived cells. Immunophenotyping showed expression of typical MSC markers and absence of hematopoietic markers. Analysis of multilineage potential demonstrated efficient differentiation into adipocytes, osteocytes, chondrocytes and induction of neuro-glial commitment. In angiogenic experiments, differentiation in endothelial cells was detected by in vitro Matrigel assay after vascular endothelial growth factor stimulation. Data obtained from karyotyping, array-comparative genomic hybridization and microsatellite genotyping comparing early with late DNA passages did not show any genomic variation at least up to passage 10. Aneuploid clones appeared in four of 14 cases at latest passages, immediately before culture growth arrest.ConclusionsOur findings indicate that hCV-MSC are genetically stable in long-term cultures at least up to passage 10 and that it is possible to achieve clinically relevant amounts of hCV-MSC even after few stages of expansion. Genome abnormalities at higher passages can occasionally occur and are always associated with spontaneous growth arrest. Under these circumstances, hCV-MSC could be suitable for therapeutic purposes.     

Parental Smoking and Risk of Childhood Brain Tumors by Functional Polymorphisms in Polycyclic Aromatic Hydrocarbon Metabolism Genes

Background

A recent meta-analysis suggested an association between exposure to paternal smoking during pregnancy and childhood brain tumor risk, but no studies have evaluated whether this association differs by polymorphisms in genes that metabolize tobacco-smoke chemicals.

Methods

We assessed 9 functional polymorphisms in 6 genes that affect the metabolism of polycyclic aromatic hydrocarbons (PAH) to evaluate potential interactions with parental smoking during pregnancy in a population-based case-control study of childhood brain tumors. Cases (N = 202) were ≤10 years old, diagnosed from 1984–1991 and identified in three Surveillance, Epidemiology, and End Results (SEER) registries in the western U.S. Controls in the same regions (N = 286) were frequency matched by age, sex, and study center. DNA for genotyping was obtained from archived newborn dried blood spots.

Results

We found positive interaction odds ratios (ORs) for both maternal and paternal smoking during pregnancy, EPHX1 H139R, and childhood brain tumors (P _interaction = 0.02; 0.10), such that children with the high-risk (greater PAH activation) genotype were at a higher risk of brain tumors relative to children with the low-risk genotype when exposed to tobacco smoke during pregnancy. A dose-response pattern for paternal smoking was observed among children with the EPHX1 H139R high-risk genotype only (OR_{no exposure} = 1.0; OR_{≤3 hours/day} = 1.32, 95% CI: 0.52–3.34; OR_>3hours/day = 3.18, 95% CI: 0.92–11.0; P _trend = 0.07).

Conclusion

Parental smoking during pregnancy may be a risk factor for childhood brain tumors among genetically susceptible children who more rapidly activate PAH in tobacco smoke.     

Identification of a Wee1–Like Kinase Gene Essential for Procyclic Trypanosoma brucei Survival

Regulation of eukaryotic cell cycle progression requires sequential activation and inactivation of cyclin-dependent kinases (CDKs). Activation of the cyclin B-cdc2 kinase complex is a pivotal step in mitotic initiation and the tyrosine kinase Wee1 is a key regulator of cell cycle sequence during G2/M transition and inhibits mitotic entry by phosphorylating the inhibitory tyrosine 15 on the cdc2 M-phase-inducing kinase. Wee1 degradation is essential for the exit from the G2 phase. In trypanosomatids, little is known about the genes that regulate cyclin B-cdc2 complexes at the G2/M transition of their cell cycle. Although canonical tyrosine kinases are absent in the genome of trypanosomatids, phosphorylation on protein tyrosine residues has been reported in Trypanosoma brucei. Here, we characterized a Wee1-like protein kinase gene from T. brucei. Expression of TbWee1 in a Schizosaccharomyces pombe strain null for Wee1 inhibited cell division and caused cell elongation. This demonstrates the lengthening of G2, which provided cells with extra time to grow before dividing. The Wee1-like protein kinase was expressed in the procyclic and bloodstream proliferative slender forms of T. brucei and the role of Wee1 in cell cycle progression was analyzed by generating RNA interference cell lines. In the procyclic form of T. brucei, the knock-down of TbWee1 expression by RNAi led to inhibition of parasite growth. Abnormal phenotypes showing an increase in the percentage of cells with 1N0K, 0N1K and 2N1K were observed in these RNAi cell lines. Using parasites with a synchronized cell cycle, we demonstrated that TbWee1 is linked to the G2/M phase. We also showed that TbWee1 is an essential gene necessary for proper cell cycle progression and parasite growth in T. brucei. Our results provide evidence for the existence of a functional Wee1 in T. brucei with a potential role in cell division at G2/M.     

IL-10 Inhibits the NF-κB and ERK/MAPK-Mediated Production of Pro-Inflammatory Mediators by Up-Regulation of SOCS-3 in Trypanosoma cruzi-Infected Cardiomyocytes

Trypanosoma cruzi (T. cruzi) infection produces an intense inflammatory response which is critical for the control of the evolution of Chagas’ disease. Interleukin (IL)-10 is one of the most important anti-inflammatory cytokines identified as modulator of the inflammatory reaction. This work shows that exogenous addition of IL-10 inhibited ERK1/2 and NF-κB activation and reduced inducible nitric oxide synthase (NOS2), metalloprotease (MMP) -9 and MMP-2 expression and activities, as well as tumour necrosis factor (TNF)-α and interleukin (IL)-6 expression, in T. cruzi-infected cardiomyocytes. We found that T. cruzi and IL-10 promote STAT3 phosphorylation and up-regulate the expression of suppressor of cytokine signalling (SOCS)-3 thereby preventing NF-κB nuclear translocation and ERK1/2 phosphorylation. Specific knockdown of SOCS-3 by small interfering RNA (siRNA) impeded the IL-10-mediated inhibition of NF-κB and ERK1/2 activation. As a result, the levels of studied pro-inflammatory mediators were restored in infected cardiomyocytes. Our study reports the first evidence that T. cruzi up- regulates SOCS-3 expression and highlights the relevance of IL-10 in the modulation of pro-inflammatory response of cardiomyocytes in Chagas’ disease.     

Alterations of Neuromuscular Function after the World's Most Challenging Mountain Ultra-Marathon

We investigated the physiological consequences of the most challenging mountain ultra-marathon (MUM) in the world: a 330-km trail run with 24000 m of positive and negative elevation change. Neuromuscular fatigue (NMF) was assessed before (Pre-), during (Mid-) and after (Post-) the MUM in experienced ultra-marathon runners (n = 15; finish time  = 122.43 hours ±17.21 hours) and in Pre- and Post- in a control group with a similar level of sleep deprivation (n = 8). Blood markers of muscle inflammation and damage were analyzed at Pre- and Post-. Mean ± SD maximal voluntary contraction force declined significantly at Mid- (−13±17% and −10±16%, P<0.05 for knee extensor, KE, and plantar flexor muscles, PF, respectively), and further decreased at Post- (−24±13% and −26±19%, P<0.01) with alteration of the central activation ratio (−24±24% and −28±34% between Pre- and Post-, P<0.05) in runners whereas these parameters did not change in the control group. Peripheral NMF markers such as 100 Hz doublet (KE: −18±18% and PF: −20±15%, P<0.01) and peak twitch (KE: −33±12%, P<0.001 and PF: −19±14%, P<0.01) were also altered in runners but not in controls. Post-MUM blood concentrations of creatine kinase (3719±3045 Ul·¹), lactate dehydrogenase (1145±511 UI·L⁻¹), C-Reactive Protein (13.1±7.5 mg·L⁻¹) and myoglobin (449.3±338.2 µg·L⁻¹) were higher (P<0.001) than at Pre- in runners but not in controls. Our findings revealed less neuromuscular fatigue, muscle damage and inflammation than in shorter MUMs. In conclusion, paradoxically, such extreme exercise seems to induce a relative muscle preservation process due likely to a protective anticipatory pacing strategy during the first half of MUM and sleep deprivation in the second half.