Cleaved PARP‐1, an Apoptotic Marker,can be Detected in Ram Spermatozoa

The presence of apoptotic features in spermatozoa has been related to lower quality and functional impairment. Members of the poly‐ADP‐ribose polymerases (PARP) familyare involved in both DNA repair and apoptosis, playing important roles in spermatogenesis. Poly‐ADP‐ribose polymerase can be cleaved by caspases, and the presence of its cleavage product (cPARP) in spermatozoa has been related to chromatin remodelling during spermatogenesis and to the activation of apoptotic pathways. There are no reports on immunodetection of cPARP in ram spermatozoa; thus, we have tested a commercially available antibody for this purpose. cPARP was microscopically detected in the acrosomal ridge of some spermatozoa (indirect immunofluorescence). A preliminary study was carried out by flow cytometry (direct immunofluorescence, FITC). Ram semen was extended in TALP and incubated for 4 h with apoptosis inducers staurosporine (10 μm ) or betulinic acid (200 μm ). Both inducers and incubation caused a significant increase in cPARP spermatozoa (0 h, control: 21.4±3.3%, inducers: 44.3±1.4%; 4 h, control: 44.3±2.4%, inducers: 53.3±1.4%). In a second experiment, we compared the sperm fractions after density gradient separation (pellet and interface). The pellet yielded a slightly lower proportion of cPARP spermatozoa (28.5±1.2% vs 36.2±2.0% in the interface; p < 0.001), and a 12‐h incubation increased cPARP similarly in both fractions (p < 0.001). cPARP seems to be an early marker of apoptosis in ram semen, although its presence in untreated samples was weakly related to worse quality (pellet/interface). We suggest to study the relationship of PARP and cPARP levels with between‐male differences on sperm fertility.     

Mastocytoma in the common carpal sheath of the digital flexor tendons of a horse

A 13-year-old Morgan gelding was examined for right forelimb lameness and tenosynovitis of the right common carpal sheath of the digital flexor tendons. The horse had moderate right forelimb lameness at the trot and marked effusion of the right common carpal sheath of the digital flexor tendons. Ultrasonographic examination revealed a soft tissue mass within the proximal pouch of the affected tendon sheath, located adjacent to the distal physis of the radius. Cytology and culture of the fluid revealed a sterile, eosinophilic tenosynovitis. Tenoscopic exploration confirmed the presence of a capsulated soft tissue mass. Thecotomy was required to fully debride the mass, which histology revealed to be a mast cell tumour. At 22 months postoperatively, the horse developed mild right forelimb lameness and eosinophilic tenosynovitis because of recurrence of the mastocytoma. Mastocytosis is a possible differential diagnosis in any horse exhibiting lameness associated with tenosynovitis. Surgical excision combined with rest and postoperative intrasynovial and systemic corticosteroids may be palliative.     

Bilateral proliferative keratitis in a Domestic Long-haired cat

A 9-year-old, female spayed, Domestic Long-haired cat was presented with bilateral, progressive, pink-white corneal opacities. The referring veterinarian had diagnosed feline herpesvirus-1 (FHV-1) keratitis though diagnostics for FHV-1 had not been performed and treatment with antibiotics and antivirals did not improve the condition. Histopathology showed neutrophils, plasma cells and lymphocytes, but no eosinophils or mast cells. Routine diagnostics did not find an underlying cause, but Southern blot analysis for FHV-1 was positive. The cat responded to topical corticosteroids and cyclosporine when used consistently.     

Influence of Ascorbic Acid and Glutathione Antioxidants on Frozen-Thawed Canine Semen

Poor sperm viability post-thaw has resulted in constant research into methods of cryopreservation of canine semen. One factor that may be involved in poor viability is sperm oxidative stress caused by excessive formation of reactive oxygen species. The present study was performed in order to evaluate the effect of different concentrations of ascorbic acid (AA) and glutathione (Glu) added to an extender for the freeze-thawing of dog sperm. Semen from five mature dogs was collected and frozen in two studies. Prior to and after freezing, sperm motility, morphology and membrane status were examined. In addition, sperm motility was examined up to 120 min after thawing to evaluate thermo-resistance. In study I, semen was collected twice from each dog. On both occasions, semen was divided into three aliquots: control, Glu 1 m m and Glu 5 m m . In study II, semen was collected twice and divided into three aliquots; control, AA 50 μ m and AA 250 μ m . Initial sperm motility was significantly higher in sperm diluted with AA 50 μ m ; sperm longevity, however, measured by a thermal-resistance test (TRT), was higher for Glu treatments. Higher concentration of Glu produced significant improvement in TRT and membrane status, whereas higher concentration of AA had a negative impact in sperm longevity. Antioxidant supplementation to semen freezing extenders improved semen quality post-thaw. Moreover, Glu had the most beneficial effect when supplemented at 5 m m .     

Relationship Between Tuber Storage Proteins and Tuber Powdery Scab Resistance in Potato

The potato genotypes (Solanum tuberosum L.) with russet tuber skin are generally resistant to powdery scab (Spongospora subterranea f.sp. subterranea or Sss). Lipoxygenase (LOX; EC 1.13.11.12) and patatin are two key storage proteins that are known to offer resistance to several diseases and insects. The objective of this study was to find out the relationship of these proteins in stored tubers with potato tuber powdery scab resistance, especially in russet skinned potatoes. An evaluation of potato germplasm with different tuber characteristics in a greenhouse environment over several years (2006–’11) suggests that russet skinned tuber genotypes (Mesa Russet, Centennial Russet and Russet Nugget) with negligible tuber disease severity index (DSI) and 100 % marketability were resistant to powdery scab. Higher physiological levels of LOX protein (on a dry weight basis) were negatively correlated with tuber DSI and positively correlated with tuber russet skin. Tuber total protein and patatin-lipase levels did not have a significant relationship with tuber powdery scab resistance. The proposed role of LOX protein in suberin- and/or non-suberin-mediated mechanisms of powdery scab resistance in russet skinned tubers are discussed here. The physiological levels of LOX protein can be considered as a useful marker for powdery scab resistance in potato breeding programs.     

Changes in tissue and plasma free amino acid concentrations after feeding in Atlantic cod

Atlantic cod, Gadus morhua, were maintained on a diet of sandeel and after a 6-day fast were refed a single meal. Concentrations of free amino acids (AAs) were measured in hepatic portal and cardiac blood as well as in the stomach and white muscle at intervals of 6h up to 24h post-feeding. The appearance of both essential and non-essential AAs in the hepatic portal blood was significantly correlated, up to 12h after feeding, to their abundance in the diet. There was a significant decline in total AA concentration in cardiac blood after 6h, followed by a significant increase at 12h. No significant changes in total AA concentration were observed in the other tissues, although mean concentration increased at 12 or 18h. At a more detailed level, the post-prandial changes in concentration of some essential AAs were consistent with their having a role in the stimulation of protein synthesis after feeding.     

An automated method of ammonia determination for use in mariculture

The precise and accurate determination of ammonia is important for both routine water management and research at a mariculture laboratory. An automated method was developed using a Technicon AA-II autoanalyser to measure total ammonia-nitrogen in seawater at both high (0–200 μmol l^?1) and low (0–10 μmol l^?1) ranges, using a single cartridge, with a precision of better than 2.2% (95% confidence). Phenol was used as the phenolic reagent, because sodium salicylate was found to be unsuitable for low level determinations of ammonia in seawater. The concentrations of nitrite usually found in mariculture tanks did not interfere significantly. Storage of filtered samples at 4°C in iodized bottles for 9 days or less gave an acceptable yield (± 5% of the initial value).     

甘蔗对生物胁迫抗性的育种

甘蔗生育期长,容易吸引大量昆虫和感染各种病害。在甘蔗品种选育程序中,甘蔗对这些生物胁迫的耐性或抗性成为首要考虑因素。要了解甘蔗生物抗性来源,需要熟悉甘蔗的分类,而各种甘蔗野生品种因具有生物抗性特征,亟待开发利用。现今种间杂交是许多甘蔗抗病育种程序的基础。文章试图简要探讨甘蔗育种的历史和今后甘蔗品种生物抗性培育的策略,详细讨论了世界大范围内出现的甘蔗病害如宿根矮化病、锈病、黑穗病等存在的主要问题。文章指出了分子标记的应用范围,基因识别的困难以及对一些抗病抗虫性状遗传转化试验取得的进展,还讨论了一些可作为目前甘蔗系谱选育方法的有效补充方法,例如先进的计算机化杂交设计方法和群体选育等,这些方法在今后甘蔗抗性品种选育中将具有很大的利用前景,可保正蔗糖生产的可持续发展。     

Evidence that the M2 membrane-spanning region lines the ion channel pore of the nicotinic receptor

Site-directed mutagenesis and expression in Xenopus oocytes were used to study acetylcholine receptors in which serine residues (i) were replaced by alanines (alpha, delta subunits) or (ii) replaced a phenylalanine (beta subunit) at a postulated polar site within the M2 transmembrane helix. As the number of serines decreased, there were decreases in the residence time and consequently the equilibrium binding affinity of QX-222, a quaternary ammonium anesthetic derivative thought to bind within the open channel. Receptors with three serine-to-alanine mutations also displayed a selective decrease in outward single-channel currents. Both the direction of this rectification and the voltage dependence of QX-222 blockade suggest that the residues mutated are within the aqueous pore of the receptor and near its cytoplasmic (inner) surface.