Hyperhomocysteinemia decreases bone blood flow

Elevated plasma levels of homocysteine (Hcy), known as hyperhomocysteinemia (HHcy), are associated with osteoporosis. A decrease in bone blood flow is a potential cause of compromised bone mechanical properties. Therefore, we hypothesized that HHcy decreases bone blood flow and biomechanical properties. To test this hypothesis, male Sprague–Dawley rats were treated with Hcy (0.67 g/L) in drinking water for 8 weeks. Age-matched rats served as controls. At the end of the treatment period, the rats were anesthetized. Blood samples were collected from experimental or control rats. Biochemical turnover markers (body weight, Hcy, vitamin B12, and folate) were measured. Systolic blood pressure was measured from the right carotid artery. Tibia blood flow was measured by laser Doppler flow probe. The results indicated that Hcy levels were significantly higher in the Hcy-treated group than in control rats, whereas vitamin B12 levels were lower in the Hcy-treated group compared with control rats. There was no significant difference in folate concentration and blood pressure in Hcy-treated versus control rats. The tibial blood flow index of the control group was significantly higher (0.78 ± 0.09 flow unit) compared with the Hcy-treated group (0.51 ± 0.09). The tibial mass was 1.1 ± 0.1 g in the control group and 0.9 ± 0.1 in the Hcy-treated group. The tibia bone density was unchanged in Hcy-treated rats. These results suggest that Hcy causes a reduction in bone blood flow, which contributes to compromised bone biomechanical properties

Development and testing of artificial membranes for rearing of Rhipicephalus microplus, the Southern Cattle Fever Tick

The southern cattle fever tick, Rhipicephalus microplus, is a livestock pest worldwide in tropical and subtropical climates, including South Texas, and can vector Babesia spp., the causal agents of bovine babesiosis. Artificial rearing methods for R. microplus are needed, especially for rearing specialist tick parasitoids that are under evaluation for classical biological control. In this study, we tested the efficiency of artificial feeding of R. microplus larvae, nymphs, and adults on a siliconized substrate (goldbeater’s membrane, lens paper, or Hemotek), or on nonsiliconized goldbeater’s membrane or Hemotek. Other variables tested were a warm water bath, incubator, positioning blood above or below ticks, using various attractants to stimulate attachment to membrane, incubating with or without 5% CO2, changing static blood once a day versus peristaltic pumping of blood, and using heparinized versus defibrinated blood. Peristaltic pumping of blood across the membrane inside the incubator significantly increased larval attachment. We found that up to 25% percent of these life stages would attach to the siliconized goldbeater’s membrane and feed, although none molted or completed their entire life cycle. A red color observable in the “fed” ticks’ legs seemed to indicate that bovine hemoglobin had penetrated the gut and entered the hemolymph of the ticks. We were successful rearing unfed nymphs to the engorged stage, which is the pre-requisite for rearing Ixoidiphagus tick parasitoids. Suggestions for future experimentation for rearing R. microplus on artificial membranes are discussed

Biotic and abiotic factors influencing infestation levels of the arundo leafminer, Lasioptera donacis, in its native range in Mediterranean Europe

Lasioptera donacis is a biological control agent of Arundo donax, which is an invasive weed in the riparian hab-itats of the Rio Grande Basin of Texas and Northern Mexico. Field research was conducted in the native range of L. donacis in Mediterranean Europe to evaluate the biotic and abiotic factors that influence its local infestation levels. Lasioptera donacis feeding damage was documented on 40.4 and 67.8 % of dead and decaying leaf sheaths respectively across all sites. Lasioptera donacis was active in all locations including highly disturbed sites, but showed a slight preference for sites near running freshwater sources and lower infestation levels adjacent to salt water sources. The environmental preferences of L. donacis in Europe are similar to conditions in the Rio Grande Basin and Southwestern U.S. where A. donax is invasive

Arthropod abundance and diversity in street trees of south Texas, USA

In urban areas, street trees provide a variety of ecological services, including biodiversity conservation. In this study we examined arthropod diversity on native and non-native street trees sampled during the fall of 2010 and spring of 2011 in McAllen, Texas, one of the most rapidly growing urban areas in the country. Eighty-eight street trees were sampled by removing arthropods from the lower canopy foliage using a hand held vacuum. Arthropods were collected into nylon bags, identified to order, and counted by morphospecies. Overall, street trees supported a significant and diverse population of arthropods: a total of 1,971 arthropods were collected, from which 12 different orders and 102 different morphospecies were identified. We found arthropod abundance was higher on street trees native to the Lower Rio Grande Valley compared to non-native trees, especially for beetles, wasps, bees, ants, and spiders. This difference was particularly striking in spring when trees were flushed with new growth. The significant deficiency of arthropods on non-native trees is indicative of their relatively low value for maintaining entomological fauna. Local land managers who aim to include biodiversity conservation in their efforts thus should enhance the urban forest through the conservation of existing native remnant trees and promoting the use of native tree species in landscaping

Incidence of the Brown dog tick, Rhipicephalus sanguineus and its parasitoid, Ixodiphagus hookeri on dogs in South Texas

The southern cattle fever tick, Rhipicephalus microplus, is a livestock pest worldwide, including South Texas, and can vector Babesia spp.; the causal agents of bovine babesiosis. Its congener, the brown dog tick, Rhipicepha-lus sanguineus, is also common worldwide and is frequently parasitized by a wasp, Ixodiphagus hookeri. To better understand the life history and host location cues of parasitic wasps of ticks, which supports the cattle fever tick eradication program for R. microplus, we examined the incidence of R. sanguineus and its parasitoid I. hookeri. Dogs in Hidalgo County, TX were observed (n=624) from Oct 2018 to April 2019. Our results show that the sampled dogs had very low levels of R. sanguineus (1.89%) with 219 nymphs, and no parasitoids were recovered. We also found that R. sanguineus nymph incidence is significantly higher on female dogs and puppies than other classes of dogs

Horticultural technique for rearing and redistribution of the sessile biological control agent, Rhizaspidiotus donacis on its host plant, Arundo donax

Arundo donax, giant reed is an invasive weed in the riparian habitats of the Rio Grande Basin. A biological control program using specialist insects from the native range in Mediterranean Europe, including the arundo scale, Rhi-zaspidiotus donacis has been implemented. The arundo scale is a sessile insect that spends most of its life cycle affixed to its host plant, thus creating challenges for its rearing and redistribution to field sites. A horticultural technique was developed which allowed for rearing of the scale on small, potted A. donax microplants, which could later be transplanted to field sites. Female scale reach maturity on the microplants and produce mobile crawler scale, which move to adjacent uninfested A. donax plants. Arundo scale were established at 48 sites on the Rio Grande using microplants. This horticultural technique allows for movement of the arundo scale at any stage of its life cycle to field sites to conduct biological control programs for A. donax where it is invasive

Importation and Preliminary Evaluation of the Stem Boring Moth Buakea kaeuae as a Potential Biological Control Agent of Invasive Guineagrass, Megathyrsus maximus

Abstract. Guineagrass, Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs, is an African grass that is invasive in Florida, Hawaii, southern Texas, and northeastern Mexico. Buakea kaeuae Moyal et al., a stem-boring African moth found only on M. maximus, was imported from Kenya and evaluated for its ability to feed and develop on Guineagrass naturalized in southern Texas. Neither larvae nor adults developed or reproduced on Texas Guineagrass. Resumen. El zacate Guinea (Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs), originario de África, es considerado invasivo en Florida, Hawaii, sur de Texas, y noreste de México. Buakea kaeuae Moyal et al. es una palomilla especifica de M. maximus que ataca a los tallos de esta maleza. Esta palomilla fue importada de Kenia y ha sido evaluada por su habilidad para alimentarse y desarrollar su ciclo biológico solo en plantas de zacate guinea, naturalizadas en el sur de Texas. Ni las larvas ni los adultos de B. kaeuae, se desarrollan y reproducen en especies de zacate Guinea de Texas

Semisynthetic flavonoid 7-O-galloylquercetin activates Nrf2 and induces Nrf2-dependent gene expression in RAW264.7 and Hepa1c1c7 cells

The natural flavonoid quercetin is known to activate the transcription factor Nrf2, which regulates the expression of cytoprotective enzymes such as heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1). In this study, a novel semisynthetic flavonoid 7-O-galloylquercetin (or quercetin-7-gallate, 3) was prepared by direct galloylation of quercetin, and its effect on the Nrf2 pathway was examined. A luciferase reporter assay showed that 7-O-galloylquercetin, like quercetin, significantly activated transcription via the antioxidant response element in a stably transfected human AREc32 reporter cell line. In addition, 7-O-galloylquercetin caused the accumulation of Nrf2 and induced the expression of HO-1 at both the mRNA and protein levels in murine macrophage RAW264.7 cells. The induction of HO-1 by 7-O-galloylquercetin was significantly suppressed by N-acetyl-l-cysteine and SB203580, indicating the involvement of reactive oxygen species and p38 mitogen-activated protein kinase activity, respectively. HPLC/MS analyses also showed that 7-O-galloylquercetin was not degalloylated to quercetin, but it was conjugated with glucuronic acid and/or methylated in RAW264.7 cells. Furthermore, 7-O-galloylquercetin was found to increase the protein levels of Nrf2 and HO-1, and also the activity of NQO1 in murine hepatoma Hepa1c1c7 cells. Taken together, we conclude that 7-O-galloylquercetin increases Nrf2 activity and induces Nrf2-dependent gene expression in RAW264.7 and Hepa1c1c7 cells

Integrable 1/r21/r^2 Spin Chain with Reflecting End

A new integrable spin chain of the Haldane-Shastry type is introduced. It is interpreted as the inverse-square interacting spin chain with a {\it reflecting end}. The lattice points of this model consist of the square roots of the zeros of the Laguerre polynomial. Using the ``exchange operator formalism'', the integrals of motion for the model are explicitly constructed.Comment: 13 pages, REVTeX3, with minor correction