Temporal and spatial expression of tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1 and -2) in the bovine corpus luteum

The matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), may mediate the dramatic structural and functional changes in the corpus luteum (CL) over the course of its life span. In addition to regulating MMP activity, TIMPs are also involved in a variety of cellular processes, including cell proliferation and steroidogenesis. In a series of initial studies, we determined that matrix metalloproteinase inhibitory activity was present in protein extracts from early (4 days old, estrus = day 0), mid (10–12 days old) and late (16 days old) CL (n = 3 for each stage). Reverse zymography revealed four metalloproteinase inhibitory protein bands with relative Molecular masses that are consistent with those reported for TIMP-1 to -4. In order to gain a better understanding of TIMPs and their role in luteal function, we further characterized this inhibitory activity with a particular focus on the temporal and spatial expression of TIMP-1 and TIMP-2 in the bovine CL. Northern blotting revealed that the TIMP-1 transcript (0.9 kb) was expressed at a higher (p \u3c 0.05) level in early and mid cycle CL than in the late stage. In contrast, two TIMP-2 mRNA species, one major 1 kb species and one minor 3.5 kb species, were significantly (p \u3c 0.05) increased in the mid and late cycle CL than in the early. Western blotting analyses demonstrated no differences in TIMP-1 (29 kDa) protein levels between early and mid stages, while its levels decreased (p \u3c 0.05) from the mid to late stage CL. Conversely, TIMP-2 (22 kDa) protein was detected at a low level in the early CL, but significantly (p \u3c 0.05) increased in the mid and late stages. Immunohistochemistry revealed that both TIMP-1 and -2 were localized to large luteal cells from all three ages of CL. TIMP-1 was also localized in capillary smooth muscle cells, while TIMP-2 was restricted to the endothelial cells in the capillary compartment. In conclusion, the different temporal expression patterns of TIMP-1 and TIMP-2 suggest that TIMP-1 may be important for luteal formation and development, while TIMP-2 may play significant roles during luteal development and maintenance. Furthermore, the distinct localization of these two inhibitors in the vascular compartment indicates that they may serve diverse physiological functions during different stages of luteal angiogenesis

The reproductive cycle of the thorny skate (Amblyraid radiata) in the western Gulf of Maine

The thorny skate (Amblyraja radiata) is a large species of skate that is endemic to the waters of the western north Atlantic in the Gulf of Maine. Because the biomass of thorny skates has recently declined below threshold levels mandated by the Sustainable Fisheries Act, commercial harvests from this region are prohibited. We have undertaken a comprehensive study to gain insight into the life history of this skate. The present study describes and characterizes the reproductive cycle of female and male thorny skates, based on monthly samples taken off the coast of New Hampshire, from May 2001 to May 2003. Gonadosomatic index (GSI), shell gland weight, follicle size, and egg case formation, were assessed for 48 female skates. In general, these reproductive parameters remained relatively constant throughout most of the year. However, transient but significant increases in shell gland weight and GSI were observed during certain months. Within the cohort of specimens sampled monthly throughout the year, a subset of females always had large preovulatory follicles present in their ovaries. With the exception of June and September specimens, egg cases undergoing various stages of development were observed in the uteri of specimens captured during all other months of the year. For males (n=48), histological stages Ill through VI (SIII-SVI) of spermatogenesis, GSI, and hepatosomatic index (HSI) were examined. Although there appeared to be monthly fluctuations in spermatogenesis, GSI, and HSI, no significant differences were found. The production and maintenance of mature spermatocysts (SVI) within the testes was observed throughout the year. These findings collectively indicate that the thorny skate is reproductively active year round

Age and growth estimates of the thorny skate (Amblyraja radiata) in the western Gulf of Maine

The northwest Atlantic population of thorny skates (Amblyraja radiata) inhabits an area that ranges from Greenland and Hudson Bay, Canada, to South Carolina. Despite such a wide range, very little is known about most aspects of the biology of this species. Recent stock assessment studies in the northeast United States indicate that the biomass of the thorny skate is below the threshold levels mandated by the Sustainable Fisheries Act. In order to gain insight into the life history of this skate, we estimated age and growth for thorny skates, using vertebral band counts from 224 individuals ranging in size from 29 to 105 cm total length (TL). Age bias plots and the coefficient of variation indicated that our aging method represents a nonbiased and precise approach for the age assessment of A. radiata. Marginal increments were significantly different between months (Kruskal-Wallis P<0.001); a distinct trend of increasing monthly increment growth began in August. Age-at-length data were used to determine the von Bertalanffy growth parameters for this population: L∞ = 127 cm (TL) and k= 0.11 for males; L∞ = 120 cm (TL) and k= 0.13 for females. The oldest age estimates obtained for the thorny skate were 16 years for both males and females, which corresponded to total lengths of 103 cm and 105 cm, respectively

Search for the Chiral Magnetic Effect in Au+Au collisions at sNN=27\sqrt{s_{_{\rm{NN}}}}=27 GeV with the STAR forward Event Plane Detectors

A decisive experimental test of the Chiral Magnetic Effect (CME) is considered one of the major scientific goals at the Relativistic Heavy-Ion Collider (RHIC) towards understanding the nontrivial topological fluctuations of the Quantum Chromodynamics vacuum. In heavy-ion collisions, the CME is expected to result in a charge separation phenomenon across the reaction plane, whose strength could be strongly energy dependent. The previous CME searches have been focused on top RHIC energy collisions. In this Letter, we present a low energy search for the CME in Au+Au collisions at $\sqrt{s_{_{\rm{NN}}}}=27$ GeV. We measure elliptic flow scaled charge-dependent correlators relative to the event planes that are defined at both mid-rapidity $|\eta|<1.0$ and at forward rapidity $2.1 < |\eta|<5.1$. We compare the results based on the directed flow plane ($\Psi_1$) at forward rapidity and the elliptic flow plane ($\Psi_2$) at both central and forward rapidity. The CME scenario is expected to result in a larger correlation relative to $\Psi_1$ than to $\Psi_2$, while a flow driven background scenario would lead to a consistent result for both event planes[1,2]. In 10-50\% centrality, results using three different event planes are found to be consistent within experimental uncertainties, suggesting a flow driven background scenario dominating the measurement. We obtain an upper limit on the deviation from a flow driven background scenario at the 95\% confidence level. This work opens up a possible road map towards future CME search with the high statistics data from the RHIC Beam Energy Scan Phase-II.Comment: main: 8 pages, 5 figures; supplementary material: 2 pages, 1 figur

Short communication: Rapid antibiotic screening tests detect antibiotic residues in powdered milk products

Rapid antibiotic screening tests are widely used in the dairy industry to monitor milk for the presence of antibiotic residues above regulated levels. Given the persistent concern over contamination of milk products with antibiotic residues, we investigated the utility of IDEXX Snap test devices (IDEXX Laboratories Inc., Westbrook, ME) as tools for detecting antibiotic residues in powdered milk products. Five powdered milk products were reconstituted according to manufacturer specification with distilled water: Carnation (Nestle USA Inc., Solon, OH), Nido youth and Nido adult (Nestle Mexico Inc., Mexico City, Mexico), ELK (Campina, Eindhoven, the Netherlands), and Regilait (Saint-Martin-Belle-Roche, France). Positive samples were generated by spiking reconstituted milk with penicillin G, cephapirin, or tetracycline to either the European Union-regulated maximum residue limit or the FDA-regulated safe/tolerance level, whichever was lower. Control, unspiked negative milk samples and positive samples were tested with appropriate IDEXX Snap test kits (penicillin G and cephapirin with New Beta-Lactam, tetracycline with New Tetracycline). All samples yielded definitive results consistent with expectations, and there were no instances of false-positive or false-negative readings. These results suggest that both the New Beta-Lactam and New Tetracycline IDEXX Snap test kits effectively detect antibiotic residues in commercially available powdered milk samples and are useful tools for monitoring antibiotic residues in reconstituted powdered milk products

A role for Cysteine-Rich 61 in the angiogenic switch during the estrous cycle in cows: regulation by prostaglandin F-2alpha

The development and demise of the corpus luteum (CL) are accompanied by angiogenic and angioregressive processes; however, the mediators of these processes have not been fully identified and characterized. Transcriptional profiling studies revealed the upregulation of cysteine-rich 61 (CYR61) in the CL, about which nothing was previously known. In the present study, we found that over a 12-h period following a single injection of prostaglandin F-2alpha (PGF(2alpha)), RT-PCR revealed the upregulation of CYR61 at 0.5 and 1 h, after which it declined. We also determined that luteal-derived endothelial cells as well as luteal steroidogenic cells are sources of CYR61. Treatment with PGF(2alpha) in vitro had no effect on CYR61 expression in luteal-derived endothelial cells, but it increased CYR61 expression in luteal steroidogenic cells. During the estrous cycle, CYR61/CYR61 (transcript/protein) was increased in the Day 4 but not in the Day 10 and Day 16 CL, suggesting that it may be associated with the switch to the angiogenic phenotype. In addition, the specific but transient upregulation of CYR61 by PGF(2alpha) in vivo, and in luteal steroidogenic cells but not endothelial cells in vitro, may be part of the mechanism underlying the previously reported transient increase in blood flow during the early onset of luteolysis. This is supported by our preliminary finding that CYR61 transiently inhibited endothelial cell expression of endothelin-converting enzyme 1 mRNA but not endothelin 1. Collectively, the increased expression of CYR61 in the Day 4 CL and its transient increase by PGF(2alpha) in Day 6, Day 10, and Day 16 CL indicate that CYR61 may play a role in regulating angiogenesis over the life span of the CL