Dextran sedimentation induces a difference in the percentage of hypodense eosinophils in peripheral blood between children with allergic asthma and healthy controls

Considerable differences in the percentage of hypodense eosinophils in the peripheral blood of asthmatics have been reported by different investigators. In these previous studies dextran sedimentation was used for removal of erythrocytes prior to density centrifugation. We hypothesized that the sedimentation procedure might induce the presence of hypodense eosinophils in the peripheral blood of asthmatic patients. In order to test this hypothesis, we compared eosinophil density profiles from peripheral blood of children with asthma and of age-matched healthy controls, using different procedures. In the first method (direct method) blood samples were directly layered on a discontinuous Percoll gradient. Erythrocytes were removed by isotonic lysis. In the second method (dextran sedimentation) erythrocytes were removed by sedimentation with dextran prior to gradient centrifugation. Results of the direct method show no significant difference in percentage of hypodense eosinophils between children with asthma and healthy controls (9.19% and 6.84% respectively). However, after dextran sedimentation, children with asthma had a significantly higher percentage of hypo-dense eosinophils than healthy controls (15.40% and 8.84% respectively; P < 0.05). The percentage of hypodense eosinophils was correlated with the number of eosinophils and with the lung function, measured as the Tiffeneau index (FEV₁/VC), in the whole group of subjects when the direct method was used. We conclude that an increased percentage of hypodense eosinophils is not present in the circulation of children with asthma, but can be induced in vitro by dextran sedimentation. Therefore, in vitro generation of hypodense eosinophils in the blood of patients with asthma seems to be related with the primed state of eosinophils.     

A 13-Week Toxicologic and Pathologic Evaluation of Prolonged Cytochromes P450 Inhibition by 1-Aminobenzotriazole in Male Rats

The pharmacologic, toxicologic, and microscopic effects of 100mg/kg/day of 1-Aminobenzotriazole (ABT), a suicide substrateinhibitor of cytochromes P450, were assessed in male Sprague-Dawleyrats over a 13-week period. Hepatic cytochromes P450 levelsand resorufin dealkylase activity were decreased to less than30% of control values beginning at Day 2 and from Day 8 to Day92. These decreases were not accompanied by overt clinical toxicity,e.g., changes in body weight, food consumption, or clinicalappearance, during the study. Hemoglobin, hematocrit, and erythrocytecounts were slightly decreased at 8, 29, and 92 days and wereaccompanied by increased spleen weights and extramedullary hematopoiesis.Additionally, mean corpuscular hemoglobin concentration, meancorpuscular volume, red cell distribution width, and mean corpuscularhemoglobin were slightly increased at 92 days. Increases inliver weights at 8, 29, and 92 days were accompanied by centrilobularhypertrophy and intracytoplasmic vacuolization consistant withlipid accumulation. Thyroid stimulating hormone (TSH) was slightlyelevated and triiodothyronine and thyroxine were slightly decreasedat 29 days. TSH was also slightly elevated at 8 and 92 days,and thyroid gland weights were increased at 8, 29, and 92 dayswith microscopic evidence of hyperplasia and hypertrophy ofthyroid gland follicular cells. Increased adrenal weights andhypertrophy of the zona fascicularis of the adrenal gland wereobserved at 8, 29, and 92 days. Kidney weights were also increasedat these assessments. Changes in the thyroid gland, the thyroidhormone profile, and the liver may reflect increased synthesisof microsomal enzymes, an effect that is sometimes difficultto demonstrate directly with suicide substrate inhibitors ofcytochromes P450. In general, the effects of daily ABT administrationto male rats at a dose that significantly reduces oxidativemetabolism over a 13-week period were considered to be well-toleratedunder controlled laboratory conditions.     

Circulating Megakaryocytes and Platelet Release in the Lung

1. Megakaryocytes were demonstrated in central venous blood of each of23 patients who underwent cardiac catheterization. Cell counts ranged from0.7 to 5.9 megakaryocytes per ml. of blood; the equivalent of one-third ofthese cells were considered to contain a full complement of cytoplasm. It hasbecome evident that megakaryocytes are normal constituents of blood.

2. In an attempt to quantify megakaryocyte migration from the bone marrow it was calculated that from 20-50 per cent of the mature megakaryocytepopulation enters the blood and ultimately reaches the lungs. The possibilitythat all megakaryocytes migrate from the marrow is not precluded with certainty by these studies.

3. It was estimated that from 7-17 per cent of the body’s platelets are released in the pulmonary capillaries. If all megakaryocytes migrate from thebone marrow, then as much as 33 per cent of the platelet population is delivered to the blood in the lungs.

Submitted on January 15, 1965 Accepted on March 13, 1965     

Advances in Therapeutic Development for Radiation Cystitis

Radiation treatment for pelvic malignancies is typically associated with radiation injury to urinary bladder that can ultimately lead to radiation cystitis (RC). The late sequelae of radiation therapy may take many years to develop and include bothersome storage symptoms such as hematuria, which may be life‐threatening in severe cases of hemorrhagic cystitis. Although no definitive treatment is currently available, various interventions are used for radiation and hemorrhagic cystitis including blood transfusion, bladder irrigation, intravesical instillation of substances such as alum, silver nitrate, prostaglandins or formalin, and fulguration of intravesical bleeding sites and surgery options such as supravesical urinary diversions and cystectomy. Effects of non‐surgical treatments for radiation and hemorrhagic cystitis are of modest success and studies are lacking to control the effects caused by RC. When such measures have proven ineffective, use of bladder botulinum toxin injection has been reported. New therapy, such as intravesical immunosuppression with local tacrolimus formulation is being developed for the treatment of radiation hemorrhagic cystitis.     

EFFECTS OF NORGESTREL AND ETHINYLOESTRADIOL INGESTION ON SERUM LEVELS OF SEX HORMONES AND GONADOTROPHINS IN MEN

DL-norgestrel and ethinyloestradiol were ingested separately and in combination by six healthy men. Serum levels of testosterone, 5α-dihydrotestosterone, oestradiol, FSH, LH and prolactin were measured before (basal), during and after ingestion of the combined drugs. Ethinyloestradiol 50 μg and DL-norgestrel 500 μg for nine days lowered the levels of testosterone to 8% (1·25 nmol/l = 0·36 ng/ml), 5α-dihydrotestosterone to 22% (0·39 nmol= 106 pg/ml), oestradiol to 46%(0·025 nmol/l = 6·88 pg/ml), FSH to 31% (0·55 U/l)and LH to 61% (2·37 U/l) of the basal values. All levels had risen on the third day after stopping the drugs and had recovered to pretreatment values within a week. Prolactin values did not show any definite trend of change during the treatment. In three men ethinyloestradiol alone, 50 μg daily for 5 days, reduced serum levels of all three sex hormones to approximately 80% of basal levels and FSH to 70% but left LH and prolactin levels unchanged. In three men DL-norgestrel alone, 525 ug daily for 4 days, reduced the androgen levels to below 40% of the basal levels, but had little effect on oestradiol levels. FSH, LH and prolactin levels were reduced to 63%, 70% and 65% respectively by the 4 days of DL-norgestrel treatment. The 26 h effects of DL-norgestrel were studied in three men who ingested 1050 ug of the drug in one dose. Serum testosterone and 5α-dihydrotestosterone levels had their greatest depression (30% and 60% respectively) at 12 to 14 h after the ingestion, whereas serum levels of DL-norgestrel peaked at 2 h after the ingestion. In this study serum FSH levels showed a clear depression in two men but LH and prolactin levels did not change. The results show a powerful effect of DL-norgestrel in reducing serum androgen levels in men, an effect which may be partly mediated through the concurrent suppression of the pituitary gonadotrophins.     

GONADAL FUNCTION IN BLOOM''S SYNDROME

Five patients with Bloom's syndrome aged from 2 8/12 to 27 years, all of whom had hypogonadism, were subjected to an i.v. LHRH test and two of them to an i.m. HCG test. There was increased responsiveness of plasma LH and FSH, indicating that the hypogonadism is primary in nature and of early development. The tubular element of the testis seems to be mainly affected, as indicated by the particularly high FSH response to LHRH stimulation, a history of sterility in the two adult patients and documented azoospermia in one of them. The Leydig cells seem to be less affected and secrete sufficient androgens to enable puberty within acceptable normal limits. Hypogonadism seems to be a major characteristic of Bloom's syndrome.     

TOURNIQUET-INDUCED HYPERTENSION

The anaesthetic records of 600 patients undergoing lower limbsurgery were reviewed to determine the frequency of intxaoperanvearterial hypertension (defined as a 30% increase in either systolicor diastolic pressure compared with the first pressure recordingafter incision). The overall frequency of hypertension duringoperation m 500 patients to whom a tourniquet was applied duringsurgery was 11% The probability of hypertension was increasedif the patient was elderly, had cardiac enlargement shown byx-ray or e c g , or had nitous oxide and narcotic anaesthesia.Pre-existing hypertension, increased serum creatirune concentration,anaemia, or treatment with antihypertensives, diuretics, orsteroids were not strongly associated with inrraoperative hypertensionA control group of 100 patients undergoing hip surgery withoutapplication of a tourniquet exhibited hypertension in 1 % ofcases     

Origin of Pulmonary Megakaryocytes

1. Evidence is presented which indicates that pulmonary megakaryocytesdo not originate in the lungs but elsewhere in the body and are carried tothe lungs in the venous blood.

2. Some megakaryocytes in the lungs evidently deliver platelets to theblood.

3. Surgery is a potent stimulus to megakaryocyte production; the numbersof megakaryocytes found in the lung postoperatively is significantly increased.

Submitted on July 3, 1964 Accepted on September 19, 1964