Evaluation of expression of Toll-Like Receptors 7 and 9, proliferation,and cytoskeletal biomarkers in plaque and guttate psoriasis: A pilot morphological study

This pilot study was aimed at comparing TLR7/TLR9 expression, cytoskeletal arrangement, and cell proliferation by indirect immunofluorescence in parallel lesional and non lesional skin samples of guttate psoriasis (PG) and psoriasis vulgaris (PV) in five male patients for each group (n=10). TLR7 expression was detected throughout all the epidermal compartment in PV samples, while in PG skin was restricted to the granular layer. TLR9 was present in the granular layer of non lesional skin and in the suprabasal layers of PV/PG lesional skin. Cell proliferation was localized in all the epidermal layers in lesional PG and PV, consistently with the immunopositivity for the “psoriatic keratin” K16. In the suprabasal layers of lesional PG and PV skin, a similar K17 expression was detected and K10 exhibited a patchy distribution. The present results suggest that TLR7 expression can be considered an intrinsic and differential histomorphological feature of PV.Key words: Keratinocyte proliferation, adaptive immunity, keratins, immunofluorescence     

Factors associated with the mass of eggs laid by tree swallows Tachycineta bicolor varied yearly between 2008 and 2016 in Michigan

The initial investment a female bird makes in an offspring is her production of its egg. The size of this investment can have important evolutionary consequences for both the female and her offspring. Between 2008 and 2016, we weighed 1977 tree swallow eggs freshly laid in nest boxes in west Michigan to investigate factors associated with egg mass. Breeding female age class was not associated with egg mass. Overall, eggs that hatched weighed significantly more than those that did not. An egg's mass was not associated with clutch size but increased with its position in the laying sequence. Females that bred multiple times showed high repeatability of egg mass. Mother–daughter narrow sense heritability of egg mass was low. There were statistically significant associations, both positive and negative, between female morphological characteristics and egg mass in some years but not others. Similarly, relationships between egg mass and weather conditions during egg formation were statistically significant in some years but not others. In summary, female characteristics and weather conditions were associated with tree swallow egg mass, but their influences varied yearly. These results reinforce the importance of long‐term studies for identifying the causes of selection that shape life‐history characteristics.     

Clonal variation in cultured neuroblastoma cells. I. Isolation and characterization of variants

Two spontaneously arising variant clones were selected from the N18 neuroblastoma cell line solely on the basis of their flattened morphology and tight adherence to the culture flask. Two other clones having the round loosely adherent morphology typical of the parent line were also selected, and flat variants were shown to arise in them upon prolonged cultivation. The flat variant clones have slower growth rates in culture, lower cloning efficiencies in suspension, and reduced acetylcholinesterase inducibility when compared with either the parent N18 line or the round cell clones. Cells of both morphologic types have high levels of plasminogen activator and are tumorigenic, although the variants have a slower growth rate in vivo, consistent with their slower growth rate in culture. SDS-polyacrylamide gel electrophoresis of total protein from the two cell types shows that the flat variants have increased amounts of a 200,000 molecular weight polypeptide that has tentatively been identified as the heavy chain of myosin. Round morphological revertants from one of the flat variant clones exhibited growth characteristics typical of the parent N18 line, but their content of myosin heavy chain, although reduced, was not so low as that in the round cell clones originally isolated. The possibility of a causal relationship between flat morphology, reduced suspension cloning efficiency, and increased content of myosin heavy chain is discussed.     

The beneficial sexually transmitted microbe hypothesis of avian copulation

Several hypotheses have been proposed to explain why femalebirds either copulate repeatedly with a single mate or copulatewith multiple partners even though only a single copulationmay be sufficient to fertilize an entire clutch. We hypothesizethat females may directly benefit from high frequencies of copulationand multiple copulation partners if they receive a cloacal inoculationof beneficial sexually transmitted microbes (STMs) that caneither protect them against future encounters with pathogensand/or serve as therapy against present infections. Experimentsin domestic animal production, wildlife rehabilitation, andclinical medicine indicate that inoculations of beneficial microbesderived from the indigenous microflora of hosts can lead tonutritional benefits, resistance to colonization by pathogens,the elimination of infection, and improved immune system functioningin recipients. Our hypothesis predicts greater copulatory rateswhen the probability of the transmission of beneficial microbesexceeds that of pathogens and when the positive effects of beneficialmicrobes on host fitness exceed the negative effects of pathogens.Patterns of copulatory behavior in birds suggest the potentialutility of our hypothesis. We discuss our hypothesis in thecontext of observed patterns of copulation in birds and proposesome ways to directly test our hypothesis. Information on the probabilitiesof transmission during copulation of beneficial and pathogenic microbesand their relative potencies in birds are needed to directlytest the predictions of our hypothesis.     

Relative genetic diversity of the rare and endangered Agave shawii ssp. shawii and associated soil microbes within a southern California ecological preserve

Shaw''s Agave (Agave shawii ssp. shawii) is an endangered maritime succulent growing along the coast of California and northern Baja California. The population inhabiting Point Loma Peninsula has a complicated history of transplantation without documentation. The low effective population size in California prompted agave transplanting from the U.S. Naval Base site (NB) to Cabrillo National Monument (CNM). Since 2008, there are no agave sprouts identified on the CNM site, and concerns have been raised about the genetic diversity of this population. We sequenced two barcoding loci, rbcL and matK, of 27 individual plants from 5 geographically distinct populations, including 12 individuals from California (NB and CNM). Phylogenetic analysis revealed the three US and two Mexican agave populations are closely related and have similar genetic variation at the two barcoding regions, suggesting the Point Loma agave population is not clonal. Agave‐associated soil microbes used significantly more carbon sources in CNM soil samples than in NB soil likely due to higher pH and moisture content; meanwhile, soil type and soil chemistry analysis including phosphorus, nitrate nitrogen, organic matter, and metals revealed significant correlations between microbial diversity and base saturation (p < 0.05, r ² = 0.3676), lime buffer capacity (p < 0.01, r ² = 0.7055), equilibrium lime buffer capacity (p < 0.01, r ² = 0.7142), and zinc (p < 0.01, r ² = 0.7136). Soil microbiome analysis within the CNM population revealed overall expected richness (H′ = 5.647–6.982) for Agave species, while the diversity range (1 − D = 0.003392–0.014108) suggests relatively low diversity marked by high individual variation. The most prominent remaining US population of this rare species is not clonal and does not seem to be threatened by a lack of genetic and microbial diversity. These results prompt further efforts to investigate factors affecting Agave''s reproduction and fitness.     

Cell Tracking Using Photoconvertible Proteins During Zebrafish Development

Embryogenesis is a dynamic process that is best studied by using techniques that allow the documentation of developmental changes in vivo. The use of genetically-encoded fluorescent proteins has proven a valuable strategy for elucidating dynamic morphogenetic processes as they occur in the intact organism. During the past decade, the development of photoactivatable and photoconvertible fluorescent proteins has opened the possibility to investigate the fate of discrete subpopulations of tagged proteins¹. Unlike photoactivatable proteins, photoconvertible fluorescent proteins (PCFPs) are readily tracked and imaged in their native emission state prior to photoconversion, making it easier to identify and select regions by optical inspection. PCFPs, such as Kaede², KikGR³, Dendra⁴ and EosFP⁵, can be shifted from green to red upon exposure to UV or blue light due to a His-Tyr-Gly tripeptide sequence which forms a green chromophore that can be photoconverted to a red one by a light-catalyzed β-elimination and subsequent extension of a π-conjugated system³. PCFPs and their monomeric variants are useful tools for tracking cells^6-10 and studying protein dynamics^11-14, respectively. During recent years, PCFPs have been expressed in different animal model, such as zebrafish⁶, chicken^7,8 and mouse^9,10 for cell fate tracking. Here we report a protocol for cell-specific photoconversion of PCFPs in the living zebrafish embryo and further tracking of photoconverted proteins at later developmental stages. This methodology allows studying, in a tissue-specific manner, cell biological events underlying morphogenesis in the zebrafish animal model.     

SUMO fosters assembly and functionality of the MutSγ complex to facilitate meiotic crossing over

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Bioreduction of aromatic aldehydes and ketones by fruits’ barks of Passiflora edulis

A series of ketones and aldehydes were reduced using plant cell preparations from fruits’ barks of Passiflora edulis in water as solvent. The reduced products were obtained in very good yields, and low to moderate enantiomeric excesses were reached with aromatic ketones and a β-ketoester. This is the first time that the biotransformation of carbonyl compounds have been successfully achieved using Passiflora species.     

Antiepileptic and neuroprotective effects of human umbilical cord blood mononuclear cells in a pilocarpine-induced epilepsy model

Status epilepticus (SE) is a condition of persistent seizure that leads to brain damage and, frequently, to the establishment of chronic epilepsy. Cord blood is an important source of adult stem cells for the treatment of neurological disorders. The present study aimed to evaluate the effects of human umbilical cord blood mononuclear cells (HUCBC) transplanted into rats after induction of SE by the administration of lithium and pilocarpine chloride. Transplantation of HUCBC into epileptic rats protected against neuronal loss in the hippocampal subfields CA1, CA3 and in the hilus of the dentate gyrus, up to 300 days after SE induction. Moreover, transplanted rats had reduced frequency and duration of spontaneous recurrent seizures (SRS) 15, 120 and 300 days after the SE. Our study shows that HUCBC provide prominent antiepileptic and neuroprotective effects in the experimental model of epilepsy and reinforces that early interventions can protect the brain against the establishment of epilepsy.