Lymphadenopathy and non-suppurative meningo-encephalitis in calves experimentally infected with bovine immunodeficiency-like virus (FL112)

In an experiment on bovine immunodeficiency-like virus (BIV), the virological and serological aspects of which were reported in an earlier paper, three groups (A, B and C) of three calves were inoculated subcutaneously with a recently isolated strain (FL112). For group B and group C, the virus was suspended in milk, and for group C (controls) the viral suspension was subjected to pasteurization before inoculation. The calves were killed for necropsy 12 months later. Clinical assessment revealed subtle ataxia in two group A calves, which took the form of an intermittent "shifting" (from one leg to another) lameness, and palpable enlargement of the pre-scapular lymph nodes in one group B animal. At necropsy, haemal lymph nodes (0.1 to 0.5 cm in diameter), occurring singly, were observed in all animals. However, in groups A and B (but not C), enlarged haemal lymph nodes (< or = 2 cm in diameter) were also seen, occurring singly and in chains; and in one group A animal they occurred in grape-like clusters. In groups A and B (but not C), histopathological examination revealed generalized hyperplastic changes in lymph nodes, especially the haemal lymph nodes. This finding was particularly striking in the two clinically ataxic animals from group A, which also showed a non-suppurative meningo-encephalitis; the latter was possibly the cause of the subtle clinical signs. This study supports previous findings on lymphadenopathy resulting from experimental infection with BIV.

Transforming growth factor-beta-mediated apoptosis in the Ramos B-lymphoma cell line is accompanied by caspase activation and Bcl-XL downregulation

Upon transforming growth factor-beta (TGF-beta) treatment, Ramos cells, a B-cell lymphoma cell line, undergo apoptosis, as measured by annexin V labeling, DNA fragmentation, and propidium iodide staining. Apoptosis could be observed by 24 h after TGF-beta exposure and occurred before the development of a significant blockage of cell cycle progression. TGF-beta-mediated apoptosis was also accompanied by a strong induction of caspase-3 subfamily activity. Incubation of cells with the caspase inhibitor Z-VAD.FMK at 20 microM, but not at 10 microM, prevented TGF-beta-induced apoptosis from occurring. By comparison, caspase-3 subfamily activity was 87% inhibited at 10 microM Z-VAD.FMK and completely inhibited at 20 microM. Because of TGF-beta's well-established role of regulating gene transcription, the mRNA levels for proteins associated with apoptosis (Fas- and Fas-associated proteins, Bcl-2 family members, IAP proteins, and I kappa B) were also studied. After 24 h of TGF-beta treatment, the most significant mRNA changes occurred with Bcl-XL (two-fold decrease) and Bik (twofold increase). TGF-beta treatment also resulted after 48 h in a fivefold decrease in Bcl-XL protein levels, based on immunoblotting analysis. Therefore, TGF-beta-mediated apoptosis involves the activation of caspases. In addition, TGF-beta transcriptionally regulates Bcl-2 family members, Bcl-XL and Bik, to further influence the apoptosis process.

A cluster of meningococcal disease in western Sydney, Australia initially associated with a nightclub

Fourteen cases of meningococcal disease (MD) occurred in August September 1996 in western Sydney, Australia. Seven of the 10 young adults affected had a direct or indirect link with a local nightclub. Ten of 11 systemic meningococcal isolates had the phenotype C:2a:P1.5 and showed close genetic relationship by pulsed-field gel electrophoresis (PFGE). Organisms of this phenotype have not previously caused outbreaks in Australia, but have been associated with outbreaks and hyperendemic serogroup C MD in Europe, Canada, and the United States. This is the largest cluster of serogroup C MD reported in urban Australia, and the first involving a nightclub. The strain differentiation results were available rapidly enough to augment epidemiological investigations on a daily basis. Public health staff could thus establish links between cases quickly, follow the spread of new cases in the community, give accurate information to health officials and the press, and utilize existing knowledge about the characteristics of this phenotype to predict likely developments during the outbreak and afterwards. The strain differentiation data was also very helpful when the role of vaccination was considered, and existing guidelines on the management of outbreaks of MD could be used effectively for the first time in western Sydney.

Cloning and characterization of human Jak-2 kinase: high mRNA expression in immune cells and muscle tissue

We report on the cloning and sequence analysis of the mRNA coding for full-length human Janus kinase 2 (Jak2). The human form of Jak2 is 1132 amino acids in length with a M(r) of 131 KDa. It has 95% sequence similarity to pig and rat Jak2. The highest level of mRNA expression was found in the spleen, peripheral blood leukocytes, and testis. Also a significantly high level of Jak2 mRNA was found in heart and skeletal muscle. Northern blot analysis showed three mRNA species in all tissues tested, except heart and skeletal muscle, of 7.6, 5.9, and 4.8 Kb. In skeletal muscle and heart, three mRNA species of 7.6, 4.8, and 3.9 Kb were identified. The catalytic domain of the human Jak2 was expressed and its specificity for phosphorylating peptide substrates derived from the gp130, STAT, and Jak3 molecules was determined and compared to that for human Jak1 and Jak3.

hUBC9 associates with MEKK1 and type I TNF-alpha receptor and stimulates NFkappaB activity

hUBC9, an E2 ubiquitin conjugating enzyme, was identified by yeast two-hybrid screening and coprecipitation studies to interact with MEKK1 and the type I TNF-alpha receptor, respectively. Because both of these proteins regulate NFkappaB activity, the role of hUBC9 in modulating NFkappaB activity was investigated. Overexpression of hUBC9 in HeLa cells stimulated the activity of NFkappaB as determined by NFkappaB reporter and IL-6 secretion assays. hUBC9 also synergized with MEKK1 to activate NFkappaB reporter activity. Thus, hUBC9 modulates NFkappaB activity which, at least in part, can be attributed to its interaction with MEKK1 and the type I TNF-alpha receptor.

Improved functional outcome in patients with early rheumatoid arthritis treated with intramuscular gold: results of a five year prospective study

OBJECTIVE

To determine whether there is a relation between disease duration and functional outcome in patients with rheumatoid arthritis (RA) treated with intramuscular sodium aurothiomolate (gold) for five years.

METHODS

440 patients with RA were enrolled in a prospective trial of gold treatment. Initial demographic details were recorded. Disease activity was assessed at yearly intervals using a combination of clinical (pain score, Ritchie articular index, duration of morning stiffness) and laboratory (erythrocyte sedimentation rate, C reactive protein) parameters. Change in functional status was assessed using the health status questionnaire (HAQ). Patients were stratified according to disease duration at outset (group 1 = 0-2 years n = 106, group 2 = > 2-5 years n = 93, and group 3 = > 5 years n = 235).

RESULTS

There were no significant differences between the groups at outset. A total of 160 patients completed five years of treatment (group 1 n = 44 (42%), group 2 n = 37 (40%), and group 3 n = 79 (34%)). Patients in group 1 had a significantly lower HAQ from year 1 to year 5 with a mean improvement of 30% at the end of the study (p < 0.001). Neither group 2 nor group 3 had a significant change in their HAQ at study end. There were significant improvements in all other variables (p < 0.05) in each group apart from pain in group 2.

CONCLUSION

Patients with early RA have a larger reversible component to their HAQ. Only patients with disease duration of up to two years have a longlasting improvement in their functional ability after starting intramuscular gold treatment.

Tumor necrosis factor locus polymorphisms in rheumatoid arthritis

We examined six polymorphic elements in the tumor necrosis factor (TNF) locus and determined their allelic distribution in 98 Caucasian rheumatoid arthritis patients in comparison with 91 ethnically-matched controls. Polymorphic elements at four biallelic sites were distributed similarly between patients and controls, irrespective of the presence or absence of DR4. Differences were observed between the two groups at the TNFa and TNFe loci, but these were consistent with extended MHC haplotypes known to be present in rheumatoid arthritis patients. Therefore, this study suggests that there is little, if any, independent contribution of the TNF locus to the genetic background for rheumatoid arthritis susceptibility.

Effect of disease modifying agents on the lipid profiles of patients with rheumatoid arthritis

OBJECTIVE

To determine the effect of intramuscular gold and oral hydroxychloroquine (HCQ) on the lipid profile of patients with rheumatoid arthritis (RA).

METHOD

A prospective randomised clinical trial of 12 months' duration was performed in 100 RA patients. Data on clinical and laboratory parameters of disease activity, and fasting serum lipid samples was collected at baseline and at three monthly intervals over one year.

RESULTS

The expected second line response was seen with no significant difference in efficacy between the groups at 12 months. The HCQ group had a significant overall improvement in their lipid profile while there was a trend for lipid profiles in the gold group to worsen.

CONCLUSIONS

HCQ is an effective second line agent that has beneficial effects on serum lipids. This should be taken into account when choosing a disease modifying anti-rheumatic drug in patients who suffer from RA and who have significant cardiovascular risk factors.

Poisoning of dairy heifers by mercurous chloride

Mercury poisoning was diagnosed in four dairy heifers, three of which died. The clinical signs were variable and included salivation, excessive thirst, extreme depression and severe diarrhoea. Postmortem examinations revealed inflammation and ulceration of the alimentary tract, pulmonary and cardiac haemorrhages, pallor of the kidney cortices and perirenal oedema. The kidney mercury concentrations were in the range 58 to 91 micrograms/g wet tissue. It is believed that the animals were poisoned by the ingestion of soil contaminated with mercurous chloride.

Prevalence of low body mass in rheumatoid arthritis: association with the acute phase response

OBJECTIVE

To ascertain the prevalence of low body mass in a rheumatoid arthritis (RA) population and to explore a possible relation with the acute phase response.

METHODS

97 patients who fulfilled the American College of Rheumatology (ACR) criteria for RA were recruited. Change in weight from initial presentation was noted. Body mass index (BMI), upper arm fat and muscle areas were recorded together with fat free mass calculated from the waist measurement. Blood samples were taken for erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and serum albumin.

RESULTS

13% of the RA group fell into the lowest 5th centile for BMI for the general population. The loss of body mass was greater for lean tissue than fat, with over 50% of the RA group falling into the lowest 10th centile of a reference population for the upper arm muscle area. Female patients who lost greater than 15% of their initial weight had higher health assessment questionnaire (HAQ) results than the rest of the group (p = 0.020). In female patients there was a significant correlation between reduced fat free mass and the acute phase response (ESR p = 0.016 and CRP p = 0.003)

CONCLUSIONS

There is an increased prevalence of low body mass, greatest for lean tissue, in the RA population. In the female group there was an inverse relation between the acute phase response and fat free mass. Female patients with RA who lose a significant amount of weight are more disabled as assessed by HAQ.