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1.  Neonatal Lipopolysaccharide Exposure Delays Puberty and Alters Hypothalamic Kiss1 and Kiss1r mRNA Expression in the Female Rat 
Journal of Neuroendocrinology  2009;21(8):683-689.
Immunological challenge experienced in early life can have long-term programming effects on the hypothalamic-pituitary-adrenal axis that permanently influence the stress response. Similarly, neonatal exposure to immunological stress enhances stress-induced suppression of the hypothalamic-pituitary gonadal (HPG) axis in adulthood, but may also affect earlier development, including the timing of puberty. To investigate the timing of the critical window for this programming of the HPG axis, neonatal female rats were injected with lipopolysaccharide (LPS; 50 μg/kg i.p.) or saline on postnatal days 3 + 5, 7 + 9, or 14 + 16 and monitored for vaginal opening and first vaginal oestrus as markers of puberty. We also investigated the effects of neonatal programming on the development of the expression patterns of kisspeptin (Kiss1) and its receptor (Kiss1r) in hypothalamic sites known to contain kisspeptin-expressing neuronal populations critical to reproductive function: the medial preoptic area (mPOA) and the arcuate nucleus in neonatally-stressed animals. We determined that the critical period for a significant delay in puberty as a result of neonatal LPS exposure is before 7 days of age in the female rat, and demonstrated that Kiss1, but not Kiss1r mRNA, expression in the mPOA is down-regulated in pre-pubertal females. These data suggest that the mPOA population of kisspeptin neurones play a pivotal role in controlling the onset of puberty, and that their function can be affected by neonatal stress.
doi:10.1111/j.1365-2826.2009.01885.x
PMCID: PMC2817439  PMID: 19500221
neonatal; LPS; puberty; kisspeptin; Kiss1; GPR54; rat
2.  Relative potency of xenobiotic estrogens in an acute in vivo mammalian assay. 
The in vivo effects of xenoestrogens are of interest in relation to their potential health risks and/or beneficial effects on humans and animals. However, the apparent in vivo potency of the examined response can be confounded by a short half-life, and the metabolism of estrogens is very dependent on the nature of conversion and/or inactivation. To minimize such variables, we examined the estrogenic potency of a range of xenoestrogens in an acute in vivo assay--the stimulation of increased uterine vascular permeability in ovariectomized mice 4 hr after subcutaneous administration. While estradiol (E 2 ) and estriol (E 3 ; a relatively weak natural estrogen) readily induced vascular responses [median effective dose (ED 50 ) <10 -9 mol], much higher amounts of xenoestrogens were required. Bisphenol A was about 10,000-fold less potent than E 2 and E 3 , and octylphenol and nonylphenol were about 100,000-fold less potent; dioctyl phthalate, benzyl butyl phthalate, dibutyl phthalate, and trichlorinated biphenol produced no effect. Coumestrol was the most active phytoestrogen, with an ED 50 between 10 -6 and 10 -7 mol; genistein was about 10-fold less potent than coumestrol, and neither daidzein nor formononetin produced any marked effect, even at doses up to 10 -5 mol. All increases in vascular permeability could be blocked by the pure antiestrogen ICI 182,780. There was no evidence that any of the compounds could act as an antiestrogen in this assay or that they could exert synergistic effects in combination. These results indicate that even short-term exposure to most of the xenobiotic estrogens can induce typical estrogenic effects in vivo , but their estrogenic potency is very weak even when assessed in an acute response.
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PMCID: PMC1532935  PMID: 9417770
3.  Further studies on caprine and ovine mycoplasmas related to Mycoplasma mycoides subsp. mycoides 
The Journal of Hygiene  1980;85(2):247-256.
Nine caprine and ovine mycoplasma strains, said to be indistinguishable serologically from Mycoplasma mycoides subsp. mycoides (the causative organism of contagious bovine pleuropneumonia; CBPP) were examined in mice by (1) a mycoplasmaemia test, and (2) a cross-protection test. Of the nine strains, two from goats belonged to a small colony (SC) type; four caprine and three ovine strains belonged to a large colony (LC) type.
The two SC strains — like a single SC strain examined in an earlier study — were indistinguishable from genuine M. mycoides subsp. mycoides as isolated from CBPP. They produced mycoplasmaemia readily. In a cross-protection test, the two SC strains and a CBPP strain immunized completely against each other.
Of the seven LC strains, six — like six LC strains examined in an earlier study — were easily distinguished from genuine M. mycoides subsp. mycoides; except for one that was not tested, all were shown to lack the ability to produce mycoplasmaemia readily. In cross-protection tests all six strains immunized partially but not completely against a CBPP strain.
The seventh LC strain (Mankefår 2833) was exceptional: it produced mycoplasmaemia readily, resembling the SC strains in this respect. Like other LC strains, in cross-protection tests it protected only partially against a CBPP strain. Strain Mankefår 2833 was isolated in ca. 1965 by Brack from a Barbary sheep (Ammotragus lervia) in a German zoo.
The ability of Mankefår 2833 to produce mycoplasmaemia enabled it to be used as a challenge strain in cross-protection tests. For the purpose of such tests the collection of nine mycoplasma strains referred to above was augmented with six LC strains from an earlier study. Partial but not complete protection against Mankefår 2833 was produced by two caprine SC strains, one CBPP strain, and nine LC strains. Three further LC strains gave protection that may have been as strong as that produced by the homologous strain, but confirmatory experiments are needed. A strain of M. mycoides subsp. capri gave no protection against Mankefår 2833.
PMCID: PMC2133930  PMID: 7005327
4.  Clostridium botulinum in soil on the site of the former Metropolitan (Caledonian) Cattle Market, London. 
The Journal of Hygiene  1979;83(2):237-241.
Sixty soil samples were collected from the redeveloped site of the former Metropolitan (Caledonian) Cattle Market, Islington, London. Of these, 15 (25%) contained Clostridium botulinum and no less than four types (B, C, D and E) were demonstrated. Early British soil surveys suggested that only 4--8% of samples contained Cl. botulinum (type A or B). Although there can be no absolute proof, it seems likely that the striking prevalence at the Market site was the result of faecal contamination by a small proportion of the many millions of farm animals brought there from elsewhere. The distribution of Clostridium tetani was uneven, but of 18 soil samples taken from one area of the Market site, 16 (89%) were positive.
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PMCID: PMC2129889  PMID: 385765
5.  Differentiation of Mycoplasma mycoides subsp. mycoides from certain closely related caprine mycoplasmas by mycoplasmaemia and cross-protection tests in mice. 
The Journal of Hygiene  1979;82(3):407-418.
In recent years, mycoplasma taxonomists have found that numerous mycoplasma strains from goats are serologically indistinguishable from Mycoplasma mycoides subsp. mycoides, the causative agent of contagious bovine pleuropneumonia (CBPP), by routinely used tests, e.g. the metabolism- and growth-inhibition tests. As a result, such organisms are now openly referred to as M. mycoides subsp. mycoides. Seven of these so-called M. mycoides subsp. mycoides strains from goats were compared with two strains of M. mycoides subsp. mycoides from CBPP, and with one strain of M. mycoides subsp. capri, by means of two in-vivo tests, namely, (1) a test of the ability of each strain, injected intraperitoneally into mice, to produce mycoplasmaemia, and (2) a cross-protection test in mice. Of the seven strains, only one ('O goat') was indistinguishable from genuine M. mycoides subsp. mycoides; it also had small colonies resembling those of genuine M. mycoides subsp. mycoides. The other six were easily distinguished from genuine M. mycoides subsp. mycoides, and they produced large colonies. These six strains and others like them should no longer be given a name that fails to distinguish them from the causative agent of CBPP. Cross-protection tests showed that the seven goat strains referred to above differed from M. mycoides subsp. capri.
PMCID: PMC2130076  PMID: 376695
6.  Clostridium botulinum in aquatic environments in Great Britain and Ireland. 
The Journal of Hygiene  1978;80(3):431-438.
Mud samples from aquatic environments in many parts of Great Britain and Ireland were collected, mainly in 1975 and 1976, and examined for Clostridium botulinum. The samples were taken from lakes, ponds, reservoirs, marshes, mudflats, streams, rivers and canals, and the sampling areas included a number of bird refuges and reserves. Of 554 samples 194 (35.0%) were positive and 167 (30.1%), 19 (3.4%), 6 (1.1%) and 15 (2.7%) contained types B, C, D and E respectively; 13 (2.3%) contained more than one type. Each type demonstrated was found in both fresh-and salt-water environments. Type B was widespread; types C, D and E were demonstrated in widely separated areas in England and Wales, and type C was found in both the north and south of Scotland. The results were compared with those reported earlier in respect of surveys in the London area, the Norfolk Boads and the Camargue (France).
PMCID: PMC2129799  PMID: 349077
7.  Surgical treatment of massive pulmonary embolism. 
California Medicine  1966;104(3):204-208.
PMCID: PMC1516245  PMID: 5936990
8.  Perineal Ectopic Testicle in a Boy, aged 17 Years 
Proceedings of the Royal Society of Medicine  1913;6(Sect Study Dis Child):195-196.
PMCID: PMC2007100  PMID: 19977375

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