Role of antibody in the protection of mice from arthritis induced by Mycoplasma pulmonis.

C3H and C57Bl10 mice exhibit a differential susceptibility to arthritis induced by Mycoplasma pulmonis. Resistant C57Bl10 mice consistently demonstrated higher complement-fixing antibody titres than susceptible C3H mice throughout the development of the acute arthritis. A strong correlation was demonstrated between the levels of anti-mycoplasma antibody and resistance to acute arthritis in six strains of mice. To test the hypothesis that the difference of arthritis resistance of C3H and C57Bl10 mice was caused by a different susceptibility of their lymphocytes to mitogenic stimulation by M. pulmonis, we investigated the generation of non-specific immunoglobulin in vivo and in vitro. M. pulmonis acted as a polyclonal mitogen, but stimulated approximately equal responses in lymphocytes of both strains.     

Giant squamous cell carcinoma of the hand: Epithelioma cuniculatum — A case report

We report a case of a giant squamous cell carcinoma of the hand. It demonstrates the natural history of a neglected well differentiated squamous cell tumour in this site. It resembles the epithelioma cuniculatum variant of squamous cell carcinoma, previously described as being peculiar to the foot. Correspondence to: Mr. C. McCormack.     

An investigation into the effects of polishing on surface hardness and corrosion of orthodontic archwires.

The purpose of this study was to investigate the effect of surface roughness on the relative corrosion rates of wires of four alloys-stainless steel, nickel titanium, cobalt chromium, and beta titanium. Batches of wire were divided into two groups. Wires in one group were industrially polished to provide a uniform surface finish; wires in the other group were left for comparison "as received." Wire diameter, hardness, and relative corrosion rates were compared within groups before and after polishing. Comparisons were also made across the four groups of alloys. The samples of as-received wires showed variations in surface finish, with beta titanium having the roughest appearance and cobalt chromium the smoothest. Nickel titanium and stainless steel surfaces were similar. Polishing provided a more uniform finish, but significantly reduced the diameter of the wires. Microhardness testing of wire surfaces of each alloy indicated that no significant work-hardening occurred as a result of polishing. The relative corrosion rates (expressed in terms of corrosion current density) in a 0.9% sodium chloride solution were estimated using the electrochemical technique of polarization resistance. Nickel titanium wires exhibited the greatest corrosion current density in the as-received state. Polishing significantly reduced the corrosion rate of nickel titanium, such that comparison between the four alloys in the polished state revealed no significant difference in their relative corrosion rate/corrosion current density.     

The psychology of facial appearance

Facial attractiveness is now recognized as being important in situations as diverse as education, relationships and employment. An individual's facial appearance is one of their most obvious characteristics and facial disfigurements are judged to be among the least desirable 'handicaps'. A face which deviates from the norm becomes a stigma. This paper looks at the complex area of facial appearance and its importance in the field of dentistry. The relationship between facial attractiveness and varying forms of dental and surgical intervention are discussed, as well as some of the problems which may be encountered during treatment.     

Tissue factor pathway inhibitor expression in human crescentic glomerulonephritis

BACKGROUND: Tissue factor (TF) pathway inhibitor (TFPI), the major endogenous inhibitor of extrinsic coagulation pathway activation, protects renal function in experimental crescentic glomerulonephritis (GN). Its glomerular expression and relationship to TF expression and fibrin deposition in human crescentic GN have not been reported. METHODS: Glomerular TFPI, TF, and fibrin-related antigen (FRA) expression were correlated in renal biopsies from 11 patients with crescentic GN. Biopsies from 11 patients with thin basement membrane disease and two normal kidneys were used as controls. RESULTS: TFPI was undetectable in control glomeruli but was detectable in interstitial microvessels. In crescentic biopsies, TFPI was detected in cellular crescents and was more prominent in fibrous/fibrocellular crescents, indicating a correlation with the chronicity of crescentic lesions. TFPI appeared to be associated with macrophages but not endothelial or epithelial cells. TFPI was generally undetectable in regions of the glomerular tuft with minimal damage. In contrast, TF and FRA were strongly expressed in regions of minimal injury, as well as in more advanced proliferative and necrotizing lesions. Despite prominent TF expression, FRA was less prominent in fibrous/fibrocellular crescents in which TFPI expression was maximal. CONCLUSIONS: These data suggest that TFPI is strongly expressed in the later stages of crescent formation and is inversely correlated with the presence of FRA in human crescentic GN. This late induction of TFPI may inhibit TF activity and favor reduced fibrin deposition in the chronic stages of crescent formation.     

Haemophilus influenzae associated scleritis

AIMS: To describe the clinical course and treatment of Haemophilus influenzae associated scleritis. METHODS: Retrospective case series. RESULTS: Three patients developed scleritis associated with ocular H influenzae infection. Past medical history, review of systems, and laboratory testing for underlying collagen vascular disorders were negative in two patients. One patient had arthritis associated with an antinuclear antibody titre of 1:160 and a Westergren erythrocyte sedimentation rate of 83 mm in the first hour. Each patient had ocular surgery more than 6 months before developing scleritis. Two had cataract extraction and one had strabismus surgery. Nodular abscesses associated with areas of scleral necrosis were present in each case. Culture of these abscesses revealed H influenzae in all patients. Treatments included topical, subconjunctival, and systemic antibiotics. Scleral inflammation resolved and visual acuity improved in each case. CONCLUSION: H influenzae infection may be associated with scleritis. Accurate diagnosis and treatment may preserve ocular integrity and good visual acuity.     

What is the price of perfection? The hidden costs of using detailed assessment instruments to measure alcohol consumption

OBJECTIVE: This article describes results from a study investigating the effects of using long assessment instruments on attrition rates in mailed-out surveys. METHOD: Participants were randomly assigned to receive one of two versions of a mailed-out survey; one version incorporated a detailed assessment of drinking using the Timeline Follow back method (TLFB; n = 46) and the other employed a brief graduated frequency measure of alcohol consumption (n = 49). RESULTS: 29% fewer respondents who received the TLFB returned any of their survey materials as compared to those respondents who received just the graduated frequency measure (22% vs 51%). CONCLUSIONS: In some situations, e.g., mailed-out surveys, employing detailed survey instruments may not be justified as the increased respondent burden may result in increased attrition rates.     

Interleukin-1β effects on cyclic GMP and cyclic AMP in cultured rat islets of Langerhans — arginine — dependence and relationship to insulin secretion

Summary When islets were cultured with interleukin-1 (1 or 100 pmol/l) for 12 h in arginine-containing medium, cyclic GMP levels were increased 1.6- and 4.5-fold respectively. The arginine analogue, N--nitro-l-arginine methyl ester, which blocks nitric oxide formation and partially reverses inhibition of insulin secretion by 100 pmol/l interleukin-1, largely, but not completely, blocked generation of cyclic GMP. Treatment of islets with 100 pmol/l interleukin-1 for 12 h significantly decreased islet cyclic AMP generation in the absence of isobutylmethylxanthine (from 13.1±0.7 to 9.3±0.8 fmol/g islet protein), this fall was arginine-dependent and may have resulted from an effect on a cyclic AMP phosphodiesterase, since it was masked if isobutylmethylxanthine was present. Isobutylmethylxanthine (0.4 mmol/l) reduced the inhibitory potency of interleukin-1 in 15 h slightly but significantly from 80.5 to 59.0%. The morpholinosydnonimine SIN-1, which is a nitric oxide donor, inhibited insulin secretion, raised islet cyclic GMP and lowered cyclic AMP; its effects were similar to those of interleukin-1. However, 6-anilinoquinoline-5,8-quinone, [LY83583 (1–10 mol/l)], inhibited insulin secretion, and significantly decreased cyclic GMP while 8-bromocyclic GMP stimulated insulin secretion. Both low- and high-dose interleukin-1 treatment give a large arginine-dependent and a small, yet significant, arginine-independent increase in cyclic GMP. The inhibitory effect of SIN-1 or interleukin-1 on insulin secretion seems to depend to a small extent on decreased islet cyclic AMP, though sustained increases in nitric oxide or depleted islet GTP may directly affect the secretory process.