Platensimycin and platencin congeners from Streptomyces platensis

Platensimycin (1a) and platencin (2) are inhibitors of FabF and FabF/H bacterial fatty acid synthase. The discovery of natural congeners is an approach that can render a better understanding of the structure-function relationships of complex natural products. The isolation and structure elucidation of nine new congeners (11-20) of platensimycin and platencin are described from a fermentation broth of Streptomyces platensis. These hydroxylated congeners are likely derived by cytochrome P450 oxidation of the terpenoid units post-cyclization. Polar groups in the terpenoid portion of the molecule produce negative interactions with the hydrophobic pocket of FabF, resulting in poor activities. However, the discovery of these compounds serves an important purpose, not only to understand structure-function relationships, which cannot be easily accessed by chemical modification, but also to provide access to compounds that could be used for structural identification/confirmation of the oxidative trace metabolites produced in vivo during animal experiments.     

Dietary advanced glycation end-products aggravate non-alcoholic fatty liver disease

AIM To determine if manipulation of dietary advanced glycation end product(AGE), intake affects nonalcoholic fatty liver disease(NAFLD) progression and whether these effects are mediated via RAGE. METHODS Male C57Bl6 mice were fed a high fat, high fructose, high cholesterol(HFHC) diet for 33 wk and compared with animals on normal chow. A third group were given a HFHC diet that was high in AGEs. Another group was given a HFHC diet that was marinated in vinegar to prevent the formation of AGEs. In a second experiment, RAGE KO animals were fed a HFHC diet or a high AGE HFHC diet and compared with wildtype controls. Hepatic biochemistry, histology, picrosirius red morphometry and hepatic mR NA were determined. RESULTS Long-term consumption of the HFHC diet generated significant steatohepatitis and fibrosis after 33 wk. In this model, hepatic 4-hydroxynonenal content(a marker of chronic oxidative stress), hepatocyte ballooning, picrosirius red staining, α-smooth muscle actin and collagen type 1A gene expression were all significantly increased. Increasing the AGE content of the HFHC diet by baking further increased these markers of liver damage, but this was abrogated by pre-marination in acetic acid. In response to the HFHC diet, RAGE-/-animals developed NASH of similar severity to RAGE+/+ animals but were protected from the additional harmful effects of the high AGE containing diet. Studies in isolated Kupffer cells showed that AGEs increase cell proliferation and oxidative stress, providing a likely mechanism through which these compounds contribute to liver injury. CONCLUSION In the HFHC model of NAFLD, manipulation of dietary AGEs modulates liver injury, inflammation, and liver fibrosis via a RAGE dependent pathway. This suggests that pharmacological and dietary strategies targeting the AGE/RAGE pathway could slow the progression of NAFLD.     

Use of the cow as a large animal model of uterine infection and immunity

For most of the reproductive cycle in both humans and animals, the uterus is clear of pathogenic bacteria. However, it is readily contaminated with pathogens, such as Escherichia and Tritichomonas species, during sexual intercourse and after parturition. Uterine infection is particularly common after parturition in cattle (Bos taurus), causing clinical disease and infertility. The endocrine and immune responses to uterine infection in cattle have been investigated in vivo and using tissue culture. Cattle are of sufficient size to permit monitoring of reproductive and immune function throughout uterine infections, and primary cell cultures are readily established. In the whole animal, uterine infections suppress GnRH and LH secretion, and inhibit the growth of ovarian follicles and their estradiol secretion. The immune response is characterized by an influx of neutrophils into the uterus and increased concentrations of acute phase proteins in peripheral plasma. In vitro, the endometrial and ovarian cell function is modified by challenge with bacteria, their products such as lipopolysaccharide or pro-inflammatory cytokines. However, it is interesting to note that the susceptibility to uterine infection and the immune response are partially regulated by the ovarian steroid hormone mileu. In conclusion, the ease of working with cattle, the availability of tissues and the similarity of uterine infection between mammals, make Bos taurus a good model for studying uterine infection and immunity.     

Who consumes functional foods and nutraceuticals in Canada? Results of cluster analysis of the 2006 survey of Canadians' demand for food products supporting health and wellness

This research seeks to identify consumer segments related to consumption of functional food and nutraceutical products in Canada. The segments are differentiated by consumer receptivity to functional foods and nutraceuticals. In turn, receptivity is tied to attitudes, motivations and knowledge related to food/diet and connections with health. At one extreme, a segment emerges that is highly receptive to functional foods and nutraceuticals, and shows a keen interest in learning about foods that have health benefits. A second segment, conversely, has low receptivity, but demonstrates a higher degree of knowledge related to the relationship between food/diet and health. A key driver of receptivity towards functional foods and nutraceuticals appears to be perceptions of disease threat, which tend to increase with age. Pre-emptive use of messages relating to the preventative properties of these products does not seem to have a major impact on the receptivity of consumers.     

Proteomic definition of normal human luminal and myoepithelial breast cells purified from reduction mammoplasties.

Normal human luminal and myoepithelial breast cells separately purified from a set of 10 reduction mammoplasties by using a double antibody magnetic affinity cell sorting and Dynabead immunomagnetic technique were used in two-dimensional gel proteome studies. A total of 43,302 proteins were detected across the 20 samples, and a master image for each cell type comprising a total of 1,738 unique proteins was derived. Differential analysis identified 170 proteins that were elevated 2-fold or more between the two breast cell types, and 51 of these were annotated by tandem mass spectrometry. Muscle-specific enzyme isoforms and contractile intermediate filaments including tropomyosin and smooth muscle (SM22) alpha protein were detected in the myoepithelial cells, and a large number of cytokeratin subclasses and isoforms characteristic of luminal cells were detected in this cell type. A further 134 nondifferentially regulated proteins were also annotated from the two breast cell types, making this the most extensive study to date of the protein expression map of the normal human breast and the basis for future studies of purified breast cancer cells.     

BNT162b2 mRNA Vaccine–Induced Immune Response in Oral Fluids and Serum

ObjectivesThe COVID-19 vaccine is currently being administered worldwide to address the ongoing pandemic. Although these vaccines have proven effective in preventing severe disease, the level of immunity required to prevent respiratory mucosal infection remains less well understood. Therefore, it is desirable to develop a noninvasive screening strategy such as oral fluid to monitor secreted antibodies longitudinally as potential surrogates of mucosal immunity.MethodsWe evaluated the anti-spike protein antibodies in gingival crevicular fluid (GCF) and saliva and compared them to immune responses in the blood of 50 healthy health care workers following 2 doses of intramuscular Pfizer/BioNTech-BNT162b2 vaccine.ResultsThe antibodies to SARS-CoV-2 spike and subdomain proteins (RBD, S1, S2, and NTD) were significantly higher in serum than oral fluids but showed a greater detection rate and higher median titres in GCF than saliva. For all tested SARS-CoV-2 antigens, IgG in GCF (as opposed to saliva) showed a more significant and stronger correlation with IgG in serum. Serum-neutralising antibodies (Nab) titres also displayed a significant and stronger correlation with anti-spike protein and their subdomains in GCF than saliva. Interestingly, the time post–second dose of vaccine and sex had a similar influence on IgG in serum and GCF. However, interferon (IFN)-γ–producing T-cell responses showed no association with SARS-Cov-2 IgG antibodies in serum, GCF, or saliva and neutralisation antibodies in serum. The correlation matrix of all measured parameters grouped serum and GCF IgG parameters separately from salivary IgG parameters indicating that GCF better represents the humoural response in serum than saliva.ConclusionsWithin limitations, we propose that GCF could be a less invasive alternative to serum and more appropriate than saliva to detect antibody responses by current COVID-19 vaccines if the GCF collection procedure could be standardised. Further research is needed to investigate the suitability of GCF for community immune surveillance for vaccines.Key words: COVID-19 vaccines, Gingival crevicular fluid, Saliva, Immunity     

Oropharyngeal epignathus with partial facial duplication: report of a rare case

Foetal oral teratoma or epignathus is a rare benign condition that originates in the oropharyngeal region. The term ‘teratoma’ refers to a mass composed of poorly organized tissues derived from each of the three germ layers. Epignathus may occur when one twin ceases development during gestation and becomes vestigial to the fully formed dominant twin. The reported incidence of epignathus is approximately 1:35,000 to 1:200,000 live births. A unique case of partial facial duplication with gross histological and radiological evidence of partial duplication of the facial elements and organs is presented herein. The affected newborn baby underwent urgent surgery due to breathing difficulties. The mass was excised successfully and the infant made an uneventful recovery. The resected specimen included two developing faces, each composed of a developing mandible and maxilla with developing tooth buds. Tissues from all three germ layers were present. In such cases, the treatment option is exclusively surgical, and complete resection is curative in most cases during the early neonatal period.     

Highly substituted terphenyls as inhibitors of parasite cGMP-dependent protein kinase activity

Parasite cGMP-dependent protein kinase (PKG) is one of the validated biochemical targets for the treatment of coccidiosis. We screened our library of natural product extracts for inhibitors of parasite PKG for the discovery of anticoccidial leads. Terferol (1) and three new terphenyls (2, 3, and 4) were isolated using bioassay-guided fractionation of the microbial extract of a Phoma sp. by a high-throughput two-step isolation method employing LH-20 and reversed-phase HPLC. These compounds inhibited parasite PKG with IC(50) values in the range 0.9-5.8 microM.