Effects of an anti-gonadoliberin releasing hormone vaccine on testicular, epididymal and spermatogenic development in the horse

The effects of the GnRH vaccine Improvac^® on testicular and epididymal morphometrics, histology and spermatogenesis were measured in 19 young (15–20 months) colts randomly assigned to one control (saline, castration at 57 days, n = 6) or either of two GnRH vaccine‐treatment groups, T‐57 (castration at 57 days, n = 7) or T‐100 (castration at 100 days, n = 6), respectively. All were immunized on Day 0 with a single booster on Day 28. Excised testes and epididymides were weighed and processed for histology to measure tubule, epithelial and muscle dimensions, the ratio of interstitial tissue to seminiferous tubules and determine the stage of spermatogenesis. Testis volume, unchanged within controls, decreased in T‐57 and T‐100 groups by 50% and 70%, respectively. Treated colts' testes were significantly lighter than controls (64% relative difference); however, epididymal mass showed no significant differences between groups. Proportionally less seminiferous tubule relative to interstitial tissue was observed in both treatment groups (5%) versus controls (22%) with a mean tubule size 28% smaller than controls. Controls exhibited a high proportion of seminiferous tubules with advanced stages of spermatogenesis, whereas treated colts showed a high proportion of tubules in the early stages of spermatogenesis. In conclusion, immunization against GnRH in prepubertal colts was effective at reducing the development of their intra‐scrotal reproductive organs and preventing normal spermatogenesis. GnRH vaccination of young colts effectively and consistently reduced testis mass, tubule size and relative proportion of seminiferous tubule tissue while retarding spermatogenesis. The epididymis showed changes with a smaller tubule diameter, lower epithelial height and thicker muscle layer recorded in treated compared to control colts.

The impact of population-based faecal occult blood test screening on colorectal cancer mortality: a matched cohort study

Background:

Randomised trials show reduced colorectal cancer (CRC) mortality with faecal occult blood testing (FOBT). This outcome is now examined in a routine, population-based, screening programme.

Methods:

Three biennial rounds of the UK CRC screening pilot were completed in Scotland (2000–2007) before the roll out of a national programme. All residents (50–69 years) in the three pilot Health Boards were invited for screening. They received a FOBT test by post to complete at home and return for analysis. Positive tests were followed up with colonoscopy. Controls, selected from non-pilot Health Boards, were matched by age, gender, and deprivation and assigned the invitation date of matched invitee. Follow-up was from invitation date to 31 December 2009 or date of death if earlier.

Results:

There were 379 655 people in each group (median age 55.6 years, 51.6% male). Participation was 60.6%. There were 961 (0.25%) CRC deaths in invitees, 1056 (0.28%) in controls, rate ratio (RR) 0.90 (95% confidence interval (CI) 0.83–0.99) overall and 0.73 (95% CI 0.65–0.82) for participants. Non-participants had increased CRC mortality compared with controls, RR 1.21 (95% CI 1.06–1.38).

Conclusion:

There was a 10% relative reduction in CRC mortality in a routine screening programme, rising to 27% in participants.

Species identification of trichomonads and associated coinfections in dogs with diarrhea and suspected trichomonosis

Trichomonads have been infrequently reported in the feces of dogs where their pathogenicity remains uncertain. It is currently unknown whether Tritrichomonas foetus or Pentatrichomonas hominis is identified more commonly in dogs with trichomonosis or how often these infections are accompanied by concurrent enteric infectious agents. The objective of this study was to determine the identity of trichomonads present in a series of 38 unsolicited canine diarrheic fecal samples submitted for T. foetus diagnostic polymerase chain reaction (PCR) testing between 2007 and 2010. We also examined each fecal sample for an association of trichomonosis with concurrent infection using a convenient real-time PCR panel for nine gastrointestinal pathogens. P. hominis, T. foetus, or both were identified by PCR in feces of 17, 1, and 1 dogs respectively. Feces from the remaining 19 dogs were PCR negative for T. foetus, P. hominis and using broader-spectrum Trichomonadida primers. The total number and specific identities of concurrent enteropathogens identified did not differ between fecal samples from dogs that were or were not identified by PCR as infected with trichomonads. These results suggest that P. hominis infection is more frequently identified than T. foetus infection in diarrheic dogs with trichomonosis and that concurrent enteropathogen infection is common in this population.

Experience with a wipe guaiac-based faecal occult blood test as an alternative test in a bowel screening programme

The format of the traditional guaiac faecal occult blood test (gFOBT), particularly the collection technique, might cause difficulties for some. A multistage evaluation of alternative tests was performed. Firstly, four tests with different faecal collection approaches were assessed: a focus group recommended further investigation of a wipe gFOBT. Secondly, 100 faecal samples were analysed using two wipe tests and the routine gFOBT: no differences were found. Thirdly, a wipe gFOBT was introduced. Over 21 months, 400 requests were made and 311 wipe kit sets were submitted for analysis: 153 (49.2%) were negative, 21 (6.8%) positive (all 3 kits positive), 96 (30.9%) weak positive (1 or 2 positive) and 41 (13.2%) un-testable. Forty-three participants were referred for colonoscopy. Outcome data were provided on 39 participants: nine declined colonoscopy, two were judged unsuitable, two did not attend, two were already in follow-up, 13 had normal colonoscopy and two normal barium enema, two had diverticular disease, two had a metaplastic polyp, four had a low-risk adenoma and one had a high-risk adenoma. No participant had cancer. Detection of significant neoplasia was small. The use of the wipe gFOBT was ceased: it cannot be recommended as a screening test for bowel cancer.

Results from the first three rounds of the Scottish demonstration pilot of FOBT screening for colorectal cancer

OBJECTIVES

To assess the effects of the first three rounds of a pilot colorectal screening programme based on guaiac faecal occult blood testing (gFOBT) and their implications for a national population-based programme.

METHODS

A demonstration pilot programme was conducted in three Scottish NHS Boards. Residents aged between 50 and 69 years registered on the Community Health Index were included in the study.

RESULTS

In the first round, the uptake was 55.0%, the positivity rate was 2.07% and the cancer detection rate was 2.1/1000 screened. In the second round, these were 53.0%, 1.90% and 1.2/1000, respectively, and in the third round, 55.3%, 1.16% and 0.7/1000, respectively. In the first round, the positive predictive value of the gFOBT was 12.0% for cancer and 36.5% for adenoma; these fell to 7.0% and 30.3% in the second round and were maintained at 7.5% and 29.1% in the third round. The percentage of screen-detected cancers diagnosed at Dukes' stage A was 49.2% in the first round, 40.1% in the second round and 36.3% in the third round.

CONCLUSIONS

These results are compatible with those of previous randomised trials done in research settings, demonstrating that population-based colorectal cancer screening is feasible in Scotland and should lead to a comparable reduction in disease-specific mortality.

Lymphangiosarcoma in a 3.5-year-old Bullmastiff bitch with vaginal prolapse, primary lymph node fibrosis and other congenital defects : clinical communication

Lymphangiosarcoma is an extremely rare tumour in dogs with only 16 cases reported in the literature. Lymphoedema, whichmaybe primary due to defects in the lymphatic system, or secondary to various other pathologies, often precedes malignancy. Of the 16 canine reports, only 1 dog was confirmed as having had prior primary lymphoedema due to aplasia of the popliteal lymph nodes. A case of lymphangiosarcoma is described in a 3.5-year-old purebred, Bullmastiff bitch which presented with vaginal blood 'spotting' for 3 weeks after cessation of oestrus, during which intromission by the male had been unsuccessful. During ovariohysterectomy a large multicystic, proliferative, spongy, fluid-filled, brownish-red mass surrounding the cervix and projecting into the abdominal space was removed with the cervix, and a diagnosis of lymphangiosarcoma made on histological and electron microscopic examination of the tissue. Ultrastructurally, no basement membrane or pericytes were found, only some of the neoplastic endothelial cells were linked by tight junctions while there were gaps between others, and neither micropinocytotic vesicles nor Weibel-Palade bodies occurred in the cells examined.Very few of the endothelial cells lining the many interlinking, tortuous maze of channels, stained slightly positive immunohistochemically for factor VIII-related antigen. The channels were filled mostly with serous fluid, and occasionally mixed leucocytes and some erythrocytes. The endothelium was often associated with underlying blocks of collagenous material, as well as looselyarranged aggregates of lymphocytes, other mononuclear cells and occasional neutrophils in the connective tissue septae and more prominently perivascularly. The bitch was discharged on antibiotic treatment but returned 2 weeks later with apparent prolapsed vagina which failed to reduce over the next week. Laparotomy revealed the tumour to have spread extensively in the caudal abdomen to involve the broad ligament and the ventral rectal serosa, and the 'prolapsed' tissue was found to be expanded vaginal wall. The bitch was euthanased and necropsied, Histological examination confirmed lymphangiosarcomatous invasion of the submucosal and muscular layers of the retroperitoneal, traumatised, prolapsed part of the vagina, the urethra and the ventral rectal wall. The broad ligament was diffusely invaded with tumour which had proliferated into the caudal abdominal space, and 3 small intra-trabecular foci of tumour were found in the right popliteal lymph node near the hilus. Mitotic figures were generally scarce. There was mild subcutaneous oedema of the ventral trunk extending from the axillae to the inner proximal thighs, which had not been evident clinically, and the lymph nodes (peripheral more so than internal) microscopically showed marked trabecular and perivascular fibrosis especially in hilar regions. Other congenital defects were hepatic capsular and central venous fibrosis with lymphatic duplication and dilatation in all areas of connective tissue, ventrally-incongruous half-circular tracheal rings, and multifocal renal dysplasia affecting the right kidney. There was locally-extensive subacute pyelonephritis of the left kidney.

Interactions between the thiol-group reagent N-ethylmaleimide and neutral and basic amino acid transporter-related amino acid transport

The neutral and basic amino acid transport protein (NBAT) expressed in renal and jejunal brush-border membranes is involved in amino acid and cystine absorption. NBAT mutations result in Type 1 cystinuria. A C-terminal myc-tagged NBAT (NBATmyc) retains the amino acid transport and protein-protein interaction properties of NBAT when expressed in Xenopus oocytes. Neutral amino acid (Ala, Phe)-cationic amino acid (Arg) heteroexchanges related to NBATmyc expression in oocytes are inactivated by treatment with the thiol-group reagent N-ethylmaleimide (NEM), although significant Arg-Arg and Ala-Ala homoexchanges persist. Inactivation of heteroexchange activity by NEM is accompanied by loss of >85% of alanine and cystine uptake, with smaller (<50%) inhibition of arginine and phenylalanine uptake. NEM-sensitive cystine uptake and arginine-alanine heteroexchange (system b(0,+) activity) are not expressed by an NBAT truncation mutant (NBATmyc-Sph1) lacking the 13 C-terminal amino acid residues, but the mutant expresses NEM-resistant transport activity (system y(+)L-like) equivalent to that of full-length NBATmyc. The deleted region of NBATmyc-Sph1 contains two cysteine residues (671/683) which may be the targets of NEM action. The synthetic amino acid 2-trifluoromethylhistidine (TFMH) stimulated alanine efflux at pH 7.5 and arginine at pH 5.5, but not vice versa, establishing the existence of distinct pathways for cationic and neutral amino acid homoexchange (TFMH is zwitterionic at pH 7.5 and cationic at pH 5.5). We suggest that NBAT expresses a combination of system b(0,+) and y(+)L-like activities, possibly by interacting with different light-chain subunits endogenous to oocytes (as does the homologous 4F2hc protein). The C-terminus of NBAT may also have an additional, direct role in the mechanism of System b(0,+) transport (the major transport activity that is defective in Type 1 cystinuria).

The Evolution of Species of the Varanidae - Microcomplement Fixation Analysis of Serum Albumins

Phylogenetic relationships among 30 of the 40 species in the Varanidae were examined in the light of molecular information on albumin evolution derived from microcomplement fixation. A phylogeny based on these results is compared with proposed phylogenies based on data obtained using other techniques. Three separate radiations of Varanus are found in Australia, The movement of varanids to Australia from south-east Asia is thought to have occurred approximately 15-20 million years ago.

Phylogeny of the Australian Rodents (Muridae) - a Molecular Approach Using Microcomplement Fixation of Albumin

Microcomplement fixation was used to assess albumin evolution in the history of the rodents of Australia. The results confirmed a monophyletic grouping consisting of the genera Pseudomys, Mastacomys and Notomys, and showed that the genus Pseudomys is paraphyletic. The genera Conilurus, Leporillus and Mesembriomys also formed a monophyletic group. A significant finding was that Leggadina was distantly related to all Pseudomys species, and indeed may be the earliest offshoot of all Australian rodents other than Rattus. Albumin evolution in the Australian rodents has occurred in a manner far from clock-like. Mastacomys Thomas, 1882 is synonymised with Pseudomys Gray, 1832.

Rates of Albumin Evolution in Parrots (Aves, Psittaciformes)

A number of lines of evidence suggest that the rate of molecular evolution in birds is slower than in other vertebrates. This hypothesis was tested by measuring the extent of amino-acid sequence divergence in albumin among species of parrots by means of microcomplement fixation. This group was chosen because its modern distribution is strongly suggestive of a Gondwanan origin. The results show that the intercontinental albumin distances are well below those expected for a Gondwanan group. These data are in accord with the hypothesis that birds have a slower rate of molecular evolution, although other explanations are possible.

Evolutionary Relationships of the Australasian Mud-Nesters (Grallinidae, Corcoracidae) - Immunological Evidence

The phylogenetic relationships of the genera of Australasian mud-nesters (Corcorax, Struthidea and Grallina) were examined by microcomplement fixation, and the results compared with morphological and DNA-DNA hybridisation data. There was general corroboration among all data sets such that (1) Corcorax and Struthidea were well-diverged members of a single lineage related to corvoids, and (2) Grallina comprised two species (Australian G. cyanoleuca and New Guinean G. bruijni) closely allied to Myiagra among the monarch flycatchers (Monarchidae). The immunological data also indicated that Corcorax and Struthidea were closer to Corvus (Corvinae) than to some other members of that subfamily identified by DNA-DNA hybridisation. There was further corroboration of evidence from DNA-DNA hybridisation for an endemic radiation among Australo-Papuan passerine families.

Immunological Evolution of Albumin in the Estrildine Finches (Aves, Passeriformes) Is Far From Clock-Like

On the basis of microcomplement fixation studies, the finch Taeniopygia guttata has an albumin whose immunological properties are very different from those of other finches. Outgroup analysis, microcomplement fixation of transferrin, and electrophoretic behaviour of finch albumin, together with phylogenetic considerations based upon chromosomes and allozymes, revealed that the difference is due to rapid change in the immunological properties of T. guttata albumin rather than to a distant relationship of T. guttata to other finches. Indeed, the immunological properties of the albumin of T. guttata has undergone about 15 times as much change as would be expected for an albumin clock. The results highlight the caution that should be exercised when applying the molecular clock ad hoc to immunological data.

Albumin Immunological Relationships of Australian Marsupials. 2. The Pseudocheiridae

Microcomplement fixation of albumin was used to examine the phylogenetic relationships among the ringtail possums, family Pseudocheiridae. Phylogenetic analysis of the data supports the hypothesis of at least three distinct clades within the family: one containing Petauroides and Hemibelideus; a second consisting of Pseudocheirus herbertensis, Ps. forbesi, Ps. mayeri, and Ps. canescens; and a third containing Ps. archeri, Ps. corinnae, Ps. cupreus and Ps. dahli. The data have not resolved the phylogenetic position of Ps. peregrinus, which may either form a separate clade or lie close to the Ps. archeri clade.

Evolutionary Relationships of Australian Marsupials as Assessed by Albumin Immunology

Current phylogenetic hypotheses of the relationships of Australian marsupials were tested by microcomplement fixation of albumin. The study involved antisera to albumins of 56 species, and cross- reactions to albumins of 199 species. The most notable and controversial features of the study were as follows. (1) Two major lineages are evident among the Australian marsupials- bandicoots-dasyuroids and diprotodontids; the marsupial mole represents a third lineage. (2) The honey possum Tarsipes is clearly a diprotodontid. (3) Acrobates and Distoechurus are monophyletic, but they are not burramyids; they are closely related to Tarsipes; moreover the Acrobates-Distoechurus-Tarsipes clade may be close to petaurids. (4) The New Guinean species of Antechinus are more closely related to the New Guinean Murexia than to Australian species of Antechinus. (5) The bandicoots fall into two groups-the New Guinean genera and the Australian genera; the bilby, Macrotis lagotis, is not clearly distinct from the bandicoots, and may be monophyletic with the New Guinean genera. (6) The banded hare-wallaby Lagostrophus is clearly the sister-group to all other extant macropodines, and may be monophyletic with potoroines rather than macropodines. (7) The genus Macropus may be paraphyletic. (8) The tree-kangaroos Dendrolagus may be closely related to the rock-wallabies and their allies (Petrogale, Peradorcas and Thylogale). (9) The genus Pseudocheirus (ringtail possums) is paraphyletic and its species are highly divergent at the molecular level. (10) The cuscuses (genus Phalanger) are probably a monophyletic assemblage.

The development of children with congenital hypothyroidism

Standardised motor, intellectual and behavioural tests were undertaken in a group of 56 children in the north of England. All were aged between five years and 15 years 11 months and all had congenital hypothyroidism. The results were compared with those of a control group. The mean IQ of the hypothyroid group was found to be 1 to 2 standard deviations below the population mean. In the group there was no correlation between developmental measures and age at diagnosis but in a subgroup with bone-age evidence of prenatal hypothyroidism there was a correlation between age at diagnosis and both intellectual and motor development. Intellectual development was normal among those treated before one month of age, but there was some evidence of disturbed fine motor and cerebellar functions.

Government health warnings and the "boomerang" effect

The experiment shows that the presence of a government health warning on cigarette advertisements can “boomerang,” leading to an increased desire to smoke. 24 housewives saw a series of 25 cigarette advertisements; for 12 subjects the health warning was present and for 12 it was absent. Half the subjects in each group were smokers and half non-smokers. The presence of the warning increased the desire to smoke but the increase seems to be greater for smokers than for non-smokers. The presence of the warning decreases the perceived goodness of the advertisement but does not affect its perceived familiarity.