Clinicopathological study of myoepithelial sialadenitis and chronic sialadenitis (sialolithiasis).

To determine any overlap in pathological features between myoepithelial sialadenitis and chronic sialadenitis/sialolithiasis histological sections from 69 cases of myoepithelial sialadenitis (MESA) (n = 7) and chronic sialadenitis/sialolithiasis (n = 62) were reviewed over a 10 year period. Three of the cases with MESA contained calculi and four of those originally diagnosed as chronic sialadenitis/sialolithiasis showed epimyoepithelial island formation. The presence of calculi should not rule out a diagnosis of MESA, particularly in the parotid gland where calculi are uncommon; as the incidence of MESA may very well be underestimated and diagnosed as chronic sialadenitis, these patients, who are at increased risk of developing lymphoma, could be lost to follow up.

Rheumatoid lymphadenopathy: a morphological and immunohistochemical study.

Sixteen lymph nodes from 14 patients with rheumatoid arthritis were examined immunohistochemically and morphometrically and compared with 10 control nodes showing follicular hyperplasia from patients without rheumatoid disease. Frozen material was available from nine patients and all controls. The nodes from patients with rheumatoid arthritis seemed to share characteristic features. The most striking of these was follicular hyperplasia in which the germinal centres, in spite of being quite large, showed relatively sparse proliferative activity. The nodes often showed infiltration of germinal centres by CD8 positive T lymphocytes and contained fewer IL2R positive cells in the paracortex than controls. These and other features may have some correlation with disease activity. Lymphadenopathy in rheumatoid arthritis may not just be a manifestation of joint inflammation but an active component of this multisystem disease and may reflect a widespread immunological abnormality.

Sarcoidosis--a cause of steroid responsive total alopecia.

We present a case of sarcoidosis complicated by total alopecia and a myopathy occurring in a young West Indian woman. There was a very satisfactory response to oral steroids.

A correlation between nuclear supercoiling and the response of patients with bladder cancer to radiotherapy.

Single cell tumour suspensions were prepared from biopsy and urine samples from 28 patients with muscle invasive transitional cell carcinoma of the bladder. Nuclear extracts (nucleoids) containing intact chromatin were isolated from these cells and the condensation of DNA supercoils measured by the light scattered from individual nucleoids within a flow cytometer. Exposure of these nucleoids to 10 micrograms ml-1 ethidium bromide produced 78.9% increase in light scatter compared to those treated with 50 micrograms ml-1. This finding is consistent with the known effect of ethidium bromide on DNA supercoiling and confirms that the light scatter signal is responding to changes at this level of DNA organisation. Cell samples were also exposed to 12 Gy of gamma radiation and the effect on nucleoid light scatter recorded. Of the patients studied prior to radiotherapy, those with persistent disease 3 months after treatment generated an increase in nucleoid light scatter of + 9.35 +/- 4.8% after 12 Gy irradiation, of these, 2/14 produced nucleoids that relaxed by more than 10% compared to controls. Those patients with no evidence of disease after radiotherapy gave an increase in nucleoid light scatter after in vitro irradiation of + 19.3 +/- 4.5% of which 10/14 (71%) relaxed by more than 10%. It is proposed that the increased relaxation within the supercoiled DNA from patients whose tumours were undetectable 3 months after therapy, is related to the inherent radiosensitivity of these tumour cells. Such a difference in nucleoid response within tumour cells from patients that responded to radiation may arise due to a decreased affinity of DNA loops for the nuclear matrix. This structural change, at a site associated with the initiation of DNA synthesis, may affect the ability of cells to continue successful cell division after radiation damage.