Intracytoplasmic Glutathione Levels in Heifer Oocytes Cultured in different Maturation Media and its Effect on Embryo Development

The present study was carried out to study the effect of different maturation media on embryo development of heifer oocytes and on their glutathione (GSH) synthesis during in vitro maturation (IVM). Immature heifer oocytes were matured in parallel in one of four maturation media: (i) Tissue Culture Medium (TCM)-199 supplemented with 10 ng/ml of epidermal growth factor (EGF); (i) TCM-199 supplemented with 10 ng/ml of EGF plus 1 microg/ml of FSH; (iii) TCM-199 supplemented with 10% of foetal bovine serum (FBS) and (iv) TCM-199 supplemented with 10% of FBS plus 1 microg/ml of FSH. Cow oocytes were used as control and were matured in TCM-199 supplemented with 10 ng/ml of EGF. No differences were observed in blastocyst rate among the different heifer oocyte groups (8.8, 7.5. 8.4 and 6.8%, respectively) however, the percentage of blastocysts obtained from cow oocytes was significantly higher (30%; p < 0.01) than those obtained from heifer oocytes. De novo GSH synthesis during oocyte maturation of heifer and cow oocytes was detected. No significant differences in intracytoplasmic GSH levels were observed among the experimental heifer oocyte groups or between heifer and cow oocytes both before and after IVM. In conclusion, the blastocyst yield obtained from heifer oocytes was lower than that from cow oocytes and this fact could not be explained by significant differences in intracytoplasmic GSH contents of oocytes before or after IVM.     

恩拉霉素的研究进展

概述了恩拉霉素的理化特性、药效学、毒理学和临床应用研究进展,展望了今后恩拉霉素的研究方向.     

Evaluation of control and treatment of Gongylonema spp. infections in callitrichids.

Numerous cases of Gongylonema spp. infection with associated pathological lesions and clinical signs were identified in a collection of Goeldi's monkeys (Callimico goeldii) (GMs) at a zoological park during a 3-yr period. An increase in the incidence of clinical signs in the GMs and other callitrichid species prompted an investigation to determine the prevalence of infection within the collection and evaluate treatment protocols. Twenty-one callitrichids [nine GMs, four golden lion tamarins (Leontopithecus rosalia), six cotton-top tamarins (Saguinus oedipus), and two golden-headed lion tamarins (Leontopithecus chrysomelas)] were included in this study. Many of the animals had been positively diagnosed on past examinations. Repeated cytological evaluations of scrapings taken from the mucosa of the tongue were performed to diagnose infection. The animals were randomly divided into two groups and treated with either ivermectin (290 microg/kg p.o., q7 days for four doses) or mebendazole (70 mg/kg p.o. q24 hr for three doses). Follow-up scrapings were performed on all animals at days 35, 64, and 156. Numerous animals displayed clinical signs (facial pruritis, inflammation, and ptyalism) before and throughout the investigation; however, Gongylonema spp. infections were only confirmed by tongue scrapings in two animals. Fecal floatation by using a sodium nitrate solution for recovery of spirurid eggs also was performed, but it yielded no positive results. The low number of confirmed cases precluded comparative evaluation of the efficacy of the anthelmintic treatment protocols. However, both regimes seemed subjectively similar in decreasing clinical signs and were safe with no adverse effects. Diagnosis of Gongylonema spp. infection is challenging, even when severe clinical signs are present. This investigation further demonstrates the lack of a reliable ante-mortem test for the parasite and underscores the importance of treatment based on clinical signs. Until a more sensitive test is available, further comparison studies on treatment regimes will be difficult and likely unrewarding.     

Vacuum-assisted closure for treatment of a deep shell abscess and osteomyelitis in a tortoise

CASE DESCRIPTION: A female Aldabra tortoise (Geochelone gigantea) was evaluated because of focal necrosis of the carapace. CLINICAL FINDINGS: Debridement revealed a 14.5 x 11.5-cm area of shell necrosis, deep abscess formation, and osteomyelitis involving bacterial (Klebsiella pneumoniae, Staphylococcus aureus, and Pseudomonas spp) and fungal pathogens. TREATMENT AND OUTCOME: Following extensive debridement, vacuum-assisted closure incorporating silver-impregnated bandaging materials was used. The wound was considered healed after 55 days, at which time a layer of epidermal tissue with progressing keratinization was present, with smooth underlying ossification. Keratinization with normal pigmentation continued over the next 67 days. CLINICAL RELEVANCE: Findings suggested that vacuum-assisted closure with silver-impregnated bandaging materials may provide advantages over traditional methods in the treatment of shell lesions in chelonians, including faster wound healing, improved cosmetic appearance of the healed wound, superior control of microbial contamination, and lower overall treatment costs.     

Temperature and surface-ocean water balance of the mid-holocene tropical western pacific

Skeletal Sr/Ca and 18O/16O ratios in corals from the Great Barrier Reef, Australia, indicate that the tropical ocean surface approximately 5350 years ago was 1 degrees C warmer and enriched in 18O by 0.5 per mil relative to modern seawater. The results suggest that the temperature increase enhanced the evaporative enrichment of 18O in seawater. Transport of part of the additional atmospheric water vapor to extratropical latitudes may have sustained the 18O/16O anomaly. The reduced glacial-Holocene shift in seawater 18O/16O ratio produced by the mid-Holocene 18O enrichment may help to reconcile the different temperature histories for the last deglaciation given by coral Sr/Ca thermometry and foraminiferal oxygen-isotope records.     

Formation of molecular chlorine from the photolysis of ozone and aqueous sea-salt particles

Halogen atoms from the reactions of sea-salt particles may play a significant role in the marine boundary layer. Reactions of sodium chloride, the major component of sea-salt particles, with nitrogen oxides generate chlorine atom precursors. However, recent studies suggest there is an additional source of chlorine in the marine troposphere. This study shows that molecular chlorine is generated from the photolysis of ozone in the presence of sea-salt particles above their deliquescence point; this process may also occur in the ocean surface layer. Given the global distribution of ozone, this process may provide a global source of chlorine.     

Hepatic CT attenuation differs in three species of freshwater turtles and hepatic Hounsfield units increase with folliculogenesis in wild Blanding's turtles (Emydoidea blandingii)

Freshwater turtle species are suffering from anthropocentric‐caused population declines, making preservation of professionally managed populations increasingly important. Turtles under professional care have an increased risk to develop hepatic lipidosis, potentially resulting in early death. Computed tomography can provide an antemortem screening for increased fatty liver composition. A goal of this prospective analytical cross‐sectional study was to assess the hepatic attenuation measured as Hounsfield units (HU) in a wild population of a freshwater turtle species, and then compare hepatic HU to freshwater turtles under professional care. Ninety‐five wild Blanding's turtles (BT; Emydoidea blandingii) as well as 10 Vietnamese Pond turtles (VPT; Mauremys annamensis) and six Northern Snake‐Necked turtles (NSNT; Chelodina oblonga) under professional care underwent CT with quantification of hepatic HU. Hepatic HU were correlated to serum chemistry findings and the presence of follicles was recorded in BT. The mean (±SD) hepatic attenuation for 95 wild BT was 97.5 HU ±9.6. There were significant differences in hepatic attenuation among VPT, NSNT, and BT, with median HU values (range) of 5.39 HU (–6.45 to 61.50), 71.74 HU (59.44‐94.49), and 95.43 HU (74.41‐124.56), respectively. Aspartate aminotransferase (AST) values had a weak negative correlation to HU with a coefficient of –0.85 (P < .001). The hepatic attenuation was significantly higher for individuals undergoing folliculogenesis (P = .007). The decreased HU values were significantly negatively correlated with AST values. Findings supported the use of CT as an aid for guiding future management practices in freshwater turtles.     

Mechanism of the Zonal Displacements of the Pacific Warm Pool: Implications for ENSO

The western equatorial Pacific warm pool is subject to strong east-west migrations on interannual time scales in phase with the Southern Oscillation Index. The dominance of surface zonal advection in this migration is demonstrated with four different current data sets and three ocean models. The eastward advection of warm and less saline water from the western Pacific together with the westward advection of cold and more saline water from the central-eastern Pacific induces a convergence of water masses at the eastern edge of the warm pool and a well-defined salinity front. The location of this convergence is zonally displaced in association with El Nino-La Nina wind-driven surface current variations. These advective processes and water-mass convergences have significant implications for understanding and simulating coupled ocean-atmosphere interactions associated with El Nino-Southern Oscillation (ENSO).     

Differential Rotation and Dynamics of the Solar Interior

Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.