Hair whorls in the dog (Canis familiaris). I. distribution.

Hair whorl characteristics were assessed in the domestic dog (Canis familiaris) in the regions of cephalic, cervical (dorsal, ventral, and lateral), thoracic and brachial axillary regions, the chest, shoulders, elbows, ventral abdominal region, and on the caudal thighs (ischiatic). They were classified as simple or tufted, and their position was recorded as the distance between their centers and bony landmarks within each region. The distribution of whorls was explored in a cohort of domestic dogs (N = 120) comprising a variety of breeds and cross-breeds, sourced from shelters (N = 60) and the general public (N = 60). Whorls observed in the majority of dogs in this cohort typically occurred on the chest, brachial axillary region, elbows, and ischiatic region. Atypical whorls were present in fewer than 20% of the population, and included those on the head (cephalic), cervical regions (dorsal, ventral, and lateral), shoulders, thoracic axillary region, and on the ventral abdominal region. The majority of whorls on dogs were classified as simple. In contrast, those located on the elbows and the majority of chest whorls were tufted. The presence and position of whorls were often associated with several variables including coat length and thickness, and the sex and source of the dog. The palpation and hair-cluster method of whorl assessment described in this article is best suited to dogs with short-to-medium coat lengths. The current methodology developed to assess hair whorl characteristics provides a framework for future investigations into any associations between hair whorl characteristics and other canine traits such as temperament.

Repeat ovum pick-up and in vitro embryo production from adult ewes with and without FSH treatment.

Ovum pick-up (OPU) was performed three times on adult ewes after synchronization with (n = 4) or without (n = 4) FSH treatment to investigate the effects of FSH treatment on the number of ovarian follicles, oocytes recovered, oocyte quality and development in vitro. FSH treatment increased the number of ovarian follicles (85 vs 162) and oocytes recovered (33 vs 91), although recovery rate was similar for ewes with and without FSH (91/162, 56.2% and 33/85, 38.8% respectively). Of the oocytes recovered, those classified as grades I and II were similar between ewes with (78/91, 85.7%) and without FSH treatment (27/33, 81.8%). The number of ovarian follicles was similar after repeated OPU for ewes treated with FSH, but for ewes not treated with FSH the number of ovarian follicles decreased with repeated OPU. The number of oocytes recovered decreased for FSH-treated ewes only, while the oocyte recovery rate and proportion of oocytes classified as grades I and II were not affected by repeated OPU. Oocyte cleavage (46/78, 58.9% and 19/24, 79.2%) and blastocyst formation (35/46, 76.1% and 12/19, 63.2% respectively) were similar for ewes with and without FSH treatment. The number of ovarian follicles varied between ewes (p < 0.05) although the number of oocytes recovered and oocyte development in vitro were similar between ewes.

Influence of hydrophilicity of cationic polymers on the biophysical properties of polyelectrolyte complexes formed by self-assembly with DNA.

To investigate the possibility of producing charge-neutral gene delivery complexes with extended, non-particulate structures, DNA was allowed to self-assemble with a series of hydrophilic cationic polymers containing quaternary charged trimethylammonio ethylmethacrylate (TMAEM, 5, 15, 50, 100 mol%) copolymerised with hydrophilic N-(2-hydroxypropyl)methacrylamide (HPMA, 95, 85, 50, 0 mol%, respectively). Copolymers were all able to bind DNA, assessed using ethidium bromide fluorescence, although copolymers with low TMAEM content did not expel ethidium bromide. Increasing TMAEM content of the copolymers changed the morphology of the complexes from extended (5-15 mol% TMAEM), through partially condensed particles (50 mol%) to discrete nanoparticles (100 mol% TMAEM). Complexes based on copolymers with low TMAEM content (5-50 mol%) showed less resistance to degradation by nucleases and lower surface charge (21.2+/-5.9-45.1+/-3.9 mV) than those formed using 100 mol% TMAEM (57.8+/-8.2 mV). They also showed significantly less association with phagocytic cells in vitro (human leucocytes, uptake decreased by up to 92.3%; murine peritoneal macrophages, uptake decreased by up to 69.6%), although in vivo their hepatic accumulation was only slightly decreased (maximum decrease 27.6%). Finding the appropriate balance of hydrophilicity and stability is key to development of effective vectors for gene delivery.

The effects of lithium and potassium on macromolecular synthesis in herpes simplex virus-infected cells.

All herpes simplex virus (HSV) infected cell-specific polypeptides (ICSPs) were synthesized in the presence of lithium at a concentration (60 mM) inhibitory to the production of infectious virus. Yields of certain ICSPs were increased and others, in particular glycoprotein C, decreased. HSV DNA synthesis was completely inhibited; synthesis and in vitro activities of HSV DNA polymerase and thymidine kinase were decreased but to a degree insufficient to account for the complete inhibition of HSV DNA synthesis. HSV DNA synthesis was inhibited to an equivalent degree by either incubation with 60 mM-lithium or by potassium starvation; both procedures decreased intracellular potassium by an equivalent amount as adjudged by X-ray microanalysis. We conclude that lithium inhibits HSV DNA synthesis by displacement of potassium from a potassium-dependent biochemical reaction or by other physiological changes brought about by the loss of cellular potassium. The possibility that lithium also directly inhibits a virus replicative event cannot be excluded.

The effects of ultraviolet and ionizing radiation on herpesviruses, SV40 and adenoviruses in relation to the small-plaque effect.

The small-plaque effect occurs with a wide range of herpesviruses following irradiation with ultraviolet light. The 37 per cent survival (D37) values, or dose required for one lethal hit (e-1), for herpes simplex, pseudorabies and pigeon herpesviruses in different cells indicate a broad spectrum of host-cell repair capacity. Other DNA-containing viruses such as SV40 and adenoviruses, which also replicate in the cell nucleus, show the small-plaque effect. Ionizing irradiation of herpes simplex virus type 1 (HSV-1) showed but little reduction in plaque-size.