Meiotic maturation of bovine oocytes in vitro: improvement of meiotic competence by dibutyryl cyclic adenosine 3',5'-monophosphate

The present study was undertaken to determine the precise stage of growth at which the ability to resume meiosis is acquired in bovine oocytes. Oocytes of various sizes were isolated from ovaries by mechanical dissection using an 18-gauge needle followed by a razor blade. This method yielded an average of 26.2 +/- 7.4 growing and fully grown oocytes from an ovary. Cumulus-enclosed oocytes were cultured in vitro in tissue culture medium 199 containing 10% fetal calf serum. Oocytes less than or equal to 90 microns in diameter did not resume meiosis. However, germinal vesicle breakdown was observed in oocytes whose diameters exceeded 91 microns. Polar body formation was observed in oocytes with diameters exceeding 101 microns. About 80% of the oocytes with diameters greater than or equal to 121 microns were able to extrude the polar body. The percentage of large oocytes (101 to 120 microns) with first polar body increased when incubated in medium containing dibutyryl cyclic adenosine 3',5'-monophosphate; however, oocytes 90 to 101 microns did not extrude the first polar body even when cultured in a medium containing dibutyryl cyclic adenosine 3',5'-monophosphate. These observations indicate that the capability to resume meiosis is acquired gradually during development of oocytes and that dibutyryl cyclic adenosine 3',5'-monophosphate can improve the meiotic competence of bovine oocytes in culture.     

Plant viruses and viroids in Japan

Journal of General Plant Pathology - An increasing number of plant viruses and viroids have been reported from all over the world due largely to metavirogenomics approaches with technological...     

Relationships between the first ovulation postpartum and polymorphism in genes relating to function of immunity, metabolism and reproduction in high-producing dairy cows

The decrease in fertility and conception rates of high-producing dairy cows is one of the major negative impacts for today's producers. The recovery of ovarian activity postpartum is affected by the status of immunity, metabolism and reproduction and plays a critical role in subsequent fertility after parturition in the cow. In the present study we investigated the relationships between polymorphisms in genes relating to the above functions and the first postpartum ovulation as a marker of the recovery of ovarian function in the cow. In immune function related-factors, the occurrence of first postpartum ovulation within 3 weeks in the C/C genotypes of tumor necrosis factor α (TNFα) exon (55.4%) and the A/G genotypes of TNFα promoter (55.4%) was significantly higher than that in T/T genotypes of TNFα exon (14.3%) and A/A genotypes of TNFα promoter (14.3%). Moreover, anovulatory cows with the T/T genotype of TNFα exon and the A/A genotype of TNFα promoter tended to have a prolonged days open compared with those of the other genotypes of TNFα polymorphisms. In metabolic function-related factors, ovulatory and anovulatory cows had a different distribution for alleles of the growth hormone receptor, but there were no significant differences in genotype and allele frequency of insulin-like growth factor-I polymorphism. No significant relationships were found between ovarian function after parturition and polymorphisms for reproduction-related genes. In conclusion, polymorphisms of TNFα gene both in exon and promoter regions have a strong association with the early first ovulation within 3 weeks after parturition in the high-producing dairy cow. Taken together, polymorphisms of TNFα gene could be strongly related to early first ovulation after parturition, thus being an effective tool of selection for improving reproductive performance in the high-producing dairy cow.     

Clinical application of plasma clearance of iohexol on feline patients

Glomerular filtration rate (GFR) was estimated by plasma clearance of iohexol (PCio) in 52 conscious cats presented for a variety of reasons to Angel Animal Hospital over a 2-year period. Cats were divided into four groups according to their clinical conditions and reasons for measuring PCio. The median PCio (ml/min/kg) was 3.68 in normal cats (NM), 2.39 in cats with suspected renal disease (SP), 1.35 in cats referred to confirm renal dysfunction (RD), and 0.84 in cats with apparent clinical signs of renal failure (RF). There was a significant difference between the results for each group. The respective medians of blood urea nitrogen (BUN) and plasma creatinine concentration (Pcr) (mg/dl) were 15 and 1.40 in NM cats, 21 and 1.71 in SP cats, 30 and 2.20 in RD cats, and 48 and 3.30 in RF cats. The reference values of BUN and Pcr were 21 +/- 7 mg/dl and 1.5 +/- 0.4 mg/dl (mean +/- SD). Diminished renal function could not be detected in SP cats by either BUN or Pcr, while a marked decrease of GFR was demonstrated before BUN and Pcr increased, indicating the insensitivity of BUN and Pcr in detecting renal dysfunction in cats. PCio can be performed non-invasively in conscious cats, which improves the veterinarian's ability to detect early stages of chronic renal disease.     

Effects of Ingesting Fucoidan Derived from Cladosiphon okamuranus Tokida on Human NK Cells: A Randomized,Double-Blind,Parallel-Group,Placebo-Controlled Pilot Study

The aim of this study was to evaluate the effects of ingesting fucoidan derived from Okinawa mozuku (Cladosiphon okamuranus) on natural killer (NK) cell activity and to assess its safety in healthy adults via a randomized, double-blind, parallel-group, placebo-controlled pilot study. Subjects were randomly divided into two groups—a placebo group (ingesting citric acid, sucralose, and caramel beverages; n = 20; 45.5 ± 7.8 years (mean ± standard deviation)) and a fucoidan group (3.0 g/day from beverages; n = 20; 47.0 ± 7.6 years); after 12 weeks, blood, biochemical, and immunological tests were performed. Clinically adverse events were not observed in any of the tests during the study period. In addition, adverse events due to the test food were not observed. In the immunological tests, NK cell activity was significantly enhanced at 8 weeks in the fucoidan group, compared to before ingestion (0 weeks). In addition, a significantly enhanced NK cell activity was observed in male subjects at 8 weeks, compared with the placebo group. These results confirm that Okinawa mozuku-derived fucoidan enhances NK cell activity and suggest that it is a safe food material.     

The effects of scallop shell extract on collagen synthesis

ABSTRACT:   Previous observations showed that scallop shells contain organic components that have various useful applications for skin. In this study, the effect of the organic components of scallop shell (scallop shell extract) on collagen metabolism is investigated. Collagen metabolism is tightly controlled by the collagen degrading matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP). Treatment of human skin fibroblast cells with the scallop shell extract increased the mRNA expression levels of type I collagen, MMP-1 and TIMP-1, suggesting that the scallop shell extract may activate collagen metabolism in skin fibroblast cells. Sirius red staining and the colorimetric quantification of collagen in fibroblast cells demonstrated that the scallop shell extract increased collagen content by approximately 1.3-fold. In vivo studies also revealed that the topical application of the scallop shell extract to rat dorsal skin increased the collagen content in the skin tissue section. These results suggest that the scallop shell extract may be effective for the treatment of photoaged and aging skin, which undergo collagen loss.     

Three-dimensional underwater shape measurement of tuna longline using ultrasonic positioning system and ORBCOMM buoy

ABSTRACT:   The installation depth of the hook in longline fishing gear has previously been measured with micro depth loggers. Research that assumes the catenary shape of longline fishing gear by a simulation based on these data has been done. However, it was not known whether the branch line was tangled with the main line or flowed with the current. In this research, an ultrasonic positioning system generally used to investigate the underwater behavior of marine organisms, and a buoy with a communications satellite, have been used, and the 3-dimensional underwater shape of tuna longline fishing gear was measured. It was possible to monitor changes in fishing gear in real time. The possibility of high precision measurement was suggested with future technical improvement.     

Spontaneous Accumulation of Globotriaosylceramide (Gb3) in Proximal Renal Tubules in an ICR Mouse

This report describes spontaneous cytoplasmic vacuolation in the proximal renal tubules of a 7-week-old male ICR [Crlj:CD1(ICR)] mouse. The contents of vacuoles were positively stained with periodic acid-Schiff (PAS) and Sudan black, and the membranes were positive on immunohistochemical staining for lysosomal-associated membrane protein-2 (LAMP-2), a marker of lysosomal membrane. Electron microscopy revealed electron-dense lamellar bodies in the proximal tubular epithelial cells. These histopathological features are similar to those in α-galactosidase A-deficient mice, in which globotriaosylceramide (Gb3), a glycosphingolipid, accumulates in lysosomes. When we performed immunohistochemical staining for Gb3, the contents of vacuoles were positively stained. From these results, spontaneous cytoplasmic vacuolation in the proximal renal tubules in the mouse was identified as lysosomal accumulation of Gb3.     

Expression of Cyclins and Cyclin‐Dependent Kinase Inhibitors in Granulosa Cells from Bovine Ovary

The regulation of granulosa cell proliferation is complex, and it is essential for normal follicular development in mammals. The aim of this study was to examine the expression of cyclins and their inhibitors in the granulosa cells of follicles at different developmental stages. Follicles were classified into three groups: oestrogen‐inactive dominant follicles (EIDs), oestrogen‐active dominant follicles (EADs) and pre‐ovulatory follicles (POs). The expression of CCND2 (cyclin D2) mRNA was significantly higher in granulosa cells from EADs and POs than in those from EIDs. The expression of CCND3 (cyclin D3) mRNA was significantly higher in granulosa cells from EADs than in those from other follicles. CCND1 (cyclin D1), CCNE1 (cyclin E1) and CCNE2 (cyclin E2) mRNA expression did not differ among the different follicular stages. The expression of CDKN1A (p21^cip1) and CDKN1B (p27^kip1) mRNA was significantly higher in granulosa cells from EIDs and POs, respectively, than in those from other follicles. Expression of CDKN2D (p19^INK4d) mRNA did not differ among the different follicular stages. Taken together, our study suggested that cyclins and their inhibitors are associated with granulosa cell proliferation at specific follicular developmental stages.     

Correction to: Comparison of biomass estimates from multiple stratification approaches in a swept area method for Pacific saury Cololabis saira in the western North Pacific

Fisheries Science - A correction to this paper has been published: https://doi.org/10.1007/s12562-021-01506-9