Long-term toxicity and carcinogenicity studies of cake made from chlorinated flour. 1. Studies in rats

Wistar rats were fed for 104 wk on cake-based diets in which the cake, prepared from unchlorinated flour, or flour treated with 1250 or 2500 ppm chlorine, formed 79% of the diet on a 12.6% moisture basis. A fourth group was fed stock diet 41B. No differences in appearance, health, behaviour or mortalities attributable to the flour treatment were observed. Female but not male mortalities were significantly higher for cake-fed rats than for those fed diet 41B. Dose-related haematological effects were seen at various stages in cake-fed rats. Dose-related increases in plasma alanine and aspartate aminotransferases were noted at 12 months in males but not in females, for whom all the values were elevated. A dose-related diminution in blood sugar at 12 months was seen only in females. A dose-related increase in urinary aspartate aminotransferase was seen only in males. Urinary N-acetylglucosaminidase activity per mg creatinine did not differ significantly between groups. At post mortem a dose-related reduction in spleen weight was found in the females only. The lesions found were those expected in ageing rats, but were observed earlier in rats fed cake. Glomerulonephrosis affected rats fed cake more than those fed diet 41B. Cake diets promoted nephrocalcinosis, unrelated to flour treatment. Increased splenic haematopoiesis occurred in about half of the females in the cake diet groups but less frequently in males or in rats fed diet 41B. Tumours were mainly chromophobe adenomas of the pituitary, common in rats. Insulomas were seen in two males in each of the groups fed on cake made from chlorinated flour, but an earlier form of this tumour was found in all cake groups and its incidence is thus regarded as unrelated to the flour treatment. The incidence of tumours of the reticuloendothelial system was not related to flour treatment. Covalent chlorine concentrations in the perirenal fat of the cake-fed rats were correlated with treatment levels, with values of 50-912 ppm in males and 59-1174 ppm in females. Since concentrations in the lipid of the diet fed to the animals were much higher than these, accumulation of the additive was absent or negligible. The chlorine concentrations in the perirenal fat of male and female rats fed diet 41B were 62 and 72 ppm respectively.

Long-term toxicity and carcinogenicity studies of cake made from chlorinated flour. 2. Studies in mice

Male and female Theiller's Original strain mice were fed for 16 and 17 months respectively on diets in which cake, prepared from flours treated with 0, 1250 or 2500 ppm chlorine, formed 79% by weight on a 12.6% moisture basis. Body weights and food intakes were unaffected by flour treatment but all of the animals on cake diets showed significant increases in body weight compared with controls on a standard diet and became obese. Mortalities in the males were not related to treatment, but in the females there was excess mortality in the treated groups compared with the cake control group, after 13 months in the 1250 group and after 15 months in the 2500 group. No consistent treatment-related effects were observed in the haematological, biochemical and renal-function studies. Dose-related increases in heart and kidney weights and a dose-related decrease in ovary weight were seen in females. No evidence of carcinogenicity resulting from flour treatment was obtained but the early ending of the study, necessitated by high mortalities, greatly diminished the value of this finding. Concentrations of covalently bound chlorine in the perirenal fat were positively correlated with treatment level, but were considerably below those present in the lipid content of the diets on which the mice were fed.

Presidential address: XVII Canadian Congress of Neurological Sciences. Cushing's disease: 50 years later

The recent improvements in transsphenoidal microsurgery have once again placed the emphasis on the basophilic adenoma of the pituitary as the etiology of the disease originally described by Harvey Cushing fifty years ago. In 75 operated cases, tumors were found in 60 cases: 52 were microadenomas, 4 were larger adenomas and 4 were invasive. In 15 cases, no tumor was found at surgery; a selective partial central hypophysectomy was performed in 11 cases and a total hypophysectomy in 4. Among the latter, 3 additional microadenomas were found at pathology. The majority of the microadenomas were located in the center of the gland most often near or within the neural lobe. In 59 patients with a non invasive tumor, initial cure was obtained in 52 (88%); only 1 of the 4 patients with an invasive tumor was cured. In the 12 cases without surgical or pathological tumor, partial or total hypophysectomy resulted in 10 cures (83%).

Bilateral trigeminal neuralgia

A 56-year-old woman previously treated by a retrogasserian neurectomy for a right tic douloureux was rendered free of pain, but complete anaesthesia of the right half of her face remained. Seven years later, she developed a typical left trigeminal neuralgia. Contralateral rhizotomy was refused because of the patient's concern about having bilateral facial anaesthesia. Through a suboccipital craniectomy, the trigeminal nerve was decompressed from a thickened arachnoid membrane and a large bridging vein near the root entry zone. After eighteen months, the patient was free of pain with intact facial sensations on the left side. Therapeutic considerations in cases of bilateral trigeminal neuralgia are discussed.

Calcifications in pituitary adenomas

In a surgical series of 755 pituitary adenomas, 51 cases (6.75%) showed intratumoral calcifications on microscopic examination and 13 of these were visible on roentgenographic examination (1.72%). Thirty-eight of these 51 cases were prolactinomas, the highest incidence being in male patients. There was no correlation between age, sex, levels of hormone, size of the tumor, and the presence of calcifications. Four patterns of radiological calcifications were encountered. Histologically, the calcifications were most frequently found within the tumor masses. Their rare occurrence within fibrous or degenerative areas speaks against their dystrophic nature. Previously reported calcified bodies in fetal and newborn pituitaries and the recently described physiological hyperprolactinemia in early infancy suggest a possible hormonal influence in the genesis of calcifications in prolactinomas.

Red cell antibodies detected in antenatal tests on rhesus positive women in South and Mid Wales, 1948-1978

A total of 733 rhesus positive women with antibodies were found during antenatal screening of 380,790 pregnancies in South and Mid Wales, over a 30-year-period. A steady increase was observed in the frequency of antibodies, particularly non-rhesus antibodies and the mothers concerned had a significantly increased history of previous blood transfusion. In 50 per cent of those with non-rhesus antibodies, transfusion was the only stimulus. Conversely, for the majority (61 per cent) of women with rhesus antibodies feto-maternal incompatibility was the sole apparent stimulus. No identifiable stimulus could be found in 25 per cent of women with anti-E and 13 per cent of those with anti-Kell. Compared to rhesus negative mothers with anti-D severe clinical haemolytic disease of the newborn was uncommon, but in 75 per cent of rhesus positive mothers with infants carrying the homologous antigen, there was some evidence of haemolytic disease. Anti-c was much the worst in this respect with 19.4 per cent of infants needing transfusion. The probability of having an incompatible infant was much less for the mothers with non-rhesus antibodies (27.3 per cent) and of these infants only 5.7 per cent needed transfusion.

Prolactin-secreting pituitary adenomas in males: transsphenoidal microsurgical treatment

Fifteen male patients with prolactin-secreting pituitary adenomas were studied before and after transsphenoidal microsurgical treatment. Loss of libido and sexual impotence were the most frequent symptoms, being present in 12. Visual defects were present in seven patients, gynecomastia was observed in four and galactorrhea was noted in three. Most of the tumours were large; only one was a microadenoma. Four patients were cured by the operation. In all the other patients the plasma levels of prolactin were significantly lowered and the visual defects corrected or lessened, but sexual impotence was not modified. No important deficiency of the pituitary gland was induced by the operation. The results indicate that in males loss of libido and sexual impotence are frequent and early manifestations of prolactinomas, and that transsphenoidal resection is a safe therapeutic approach.

Cushing's disease: management by transsphenoidal pituitary microsurgery

Over 15 yr, 24 patients underwent transsphenoidal pituitary surgery for Cushing's disease with a median follow-up of 12 months. Cures included 7 patients with normal sella turcicas (6 microadenomas), 6 patients with focal depressions (6 microadenomas) of the sella (grade I), and 3 patients (3 adenomas) with enlarged sellas (grade II). Three patients with sella destruction (grades III and IV), 2 with normal sellas, and 1 with focal sella depression (grade I) were not cured. Two apparent cures (microadenomas) recurred. Tumor histology revealed 19 basophilic adenomas; electron microscopy (14 tumors) and immunochemical studies (10 tumors) revealed only ACTH cells. Circadian rhythm returned in 6 cured patients. Impotence (in 2), amenorrhea (in 7), and galactorrhea (in 3) resolved in affected cured patients. The major surgical complication was hemorrhage at the operative site (3 patients). Transsphenoidal pituitary surgery is a valuable method for managing Cushing's disease in many patients.

Geniculate neuralgia and audio-vestibular disturbances due to compression of the intermediate and eighth nerves by the postero-inferior cerebellar artery

A compression of the intermediate, cochlear and vestibular parts of the VIII nerve by a redundant loop of the posterior inferior cerebellar artery (PICA) was found at autopsy in a patient who suffered during 21 years of geniculate neuralgia associated with tinnitus, hypoacousia and occasional dizziness. The relationship of arterial cross compression to geniculate neuralgia and audio-vestibular disturbance is discussed.

Hyperthyroidism due to a pituitary TSH secreting tumour with amenorrhoea-galactorrhoea

A 20-year-old female presented with thyrotoxicosis associated with amenorrhoea and galactorrhoea after oral contraceptive withdrawal. Serum TSH was persistently elevated (mean: 28 +/- 3.1 microU/ml during 24-h sampling and did not vary significantly after TRH, bromocriptine or somatostatin. Prolactin levels remained constantly at the upper limit of normal (mean: 20.6 +/- 2.1 ng/ml, with a minimal increase after TRH, a slight decrease after somatostatin (54%) and a marked decrease after bromocriptine (88.5%). Surgical exploration revealed an unusually firm tumour adherant to the wall of the sella turcia; electron microscopic study showed that it was composed almost exclusively of thyrotrophs. After a transient period of euthyroidism post-operatively, T3 toxicosis occurred with an increased TSH level (15.5 microU/ml) and a rise in TSH and alpha subunit in response to TRH. An increase in T4 followed while prolactin remained low.

Primary aberrant third nerve regeneration

The clinical and neuroradiological features in 4 patients with the syndrome of aberrant regeneration of the third nerve are presented. In contrast to what is commonly seen, the syndrome was not preceded by third nerve palsy. A petrous apex-cavernous sinus meningioma was the underlying lesion in all 4 patients. Surgical and pathological confirmation of the diagnosis was obtained in 3. Regardless of whether the other ocular motor nerves are spared (as in our patients) or involved (as in other cases reported in the literature), primary aberrant regeneration of the oculomotor nerve appears to be characteristic of a cavernous sinus meningioma.

Laser photocoagulation for treatment of experimental aneurysms

Twenty-five autologous, artificially implanted venous and arterial aneurysms were treated by argon laser photocoagulation. Sequential angiographic follow-up studies and final histologic studies demonstrated complete secondary occlusion in 11 cases, significant reduction of the aneurysm lumen in 10 cases, and no change in 4 cases. Delayed secondary occlusion appears to involve an active biologic process with progressive fibroblastic proliferation in the aneurysm wall.

The transsphenoidal surgical approach to the pituitary

The operating microscope and intraoperative fluoroscopic monitoring have converted this approach from a blind procedure into a precise operation that permits selective (as well as nonselective) resection of pituitary tumors, often restoring function to normal or near-normal levels. Experience with the technique has also shed new light on the pathophysiology of acromegaly, Cushing's disease, and hyperprolactinemia.