Role of monokines in control of anterior pituitary hormone release

It has long been known that endogenous pyrogen, released as a result of injection of typhoid vaccine or in response to infection, produces fever and increases ACTH secretion. Recent studies have indicated that endogenous pyrogen is, at least in part, IL-1. This monokine has now been shown to activate the release of ACTH by a hypothalamic mechanism with release of CRF and possibly vasopressin, which stimulates the corticotrophs. There may also be a pituitary action to stimulate the release of ACTH directly. In our experiments we showed that IL-1 at low but not higher doses appears to act intrahypothalamically to stimulate GH and PRL release and to inhibit TSH release. In the meantime, another monokine, cachectin, was isolated and its structure determined. We have found that this monokine can act following its third ventricular injection to stimulate ACTH, PRL, and GH release and to inhibit TSH release, at least in part, by release of prostaglandins since indomethacin, an inhibitor of prostaglandin synthesis, produced a blockade of the responses except for those of ACTH. This peptide also has highly potent effects to alter pituitary hormone release by direct action on the pituitary to stimulate ACTH, GH, and TSH and to a slight extent PRL release. These actions appear to involve prostaglandins since indomethacin blocks all of the effects except for the effect on ACTH secretion. This monokine also produces a dose-related lowering of anterior pituitary cyclic AMP levels. When the monokine was incubated along with somatostatin, the lowering of cyclic AMP was reversed, and a potent PRL-releasing effect of the monokine was visible. We have begun studies with a third monokine, gamma interferon, which indicate that it stimulates ACTH release but suppresses plasma GH and TSH levels by a hypothalamic action. It is apparent that these various monokines have powerful effects to alter hypothalamic-pituitary function and that they probably mediate most of the effects of infections on the release of anterior pituitary hormones.

Platelet antiaggregatory effect of triflusal in human whole blood

An in vitro and ex vivo study has been made to determine the inhibition of platelet aggregation in human whole blood (WB) and platelet rich plasma by triflusal and its main metabolite HTB (2-hydroxy-4-trifluoromethylbenzoic acid). Triflusal was administered orally at 300 mg x 2/day, for 15 days, to 13 healthy volunteers (ex vivo tests). Triflusal and HTB, at concentrations lower than 1 mM, produced a significant inhibition of platelet aggregation induced by ADP (2.5 microM, final) and collagen (1 microgram/ml, final) in PRP, while about 50% inhibition was induced in WB samples at 0.12 mM. Ex vivo studies also revealed a stronger inhibitory effect of triflusal in WB samples against several inducers; differences were particularly pronounced against ADP (10.6 times more potent in WB). These results suggest an important role of red blood cells and/or leukocytes in the mechanism of action of triflusal. The antiplatelet effect of triflusal in WB was modified when incubated with HTB at therapeutic concentrations. The IC50 value against collagen increased from 82 to 140 microM with 37.5 microM HTB, but decreased in a dose-dependent manner when incubated with higher concentrations of HTB, suggesting that inhibition of platelet cyclooxygenase by HTB masks its negative interaction with triflusal.

[C-reactive protein, lactate and LDH isoenzymes in the cerebrospinal fluid in the diagnosis in childhood meningitis]

C reactive protein lactate and LDH isoenzymes were quantified in CSF of 32 children with meningitis (27 bacterial and 5 viral). Results in cases with bacterial meningitis were as follows. C reactive protein sensitivity was 11.1% and specificity was 100%. Lactate sensitivity was 33.3% and its specificity was 80%. LDH1 and LDH5 had a sensitivity of 44.4%, and specificities of 100 and 60% respectively. Considering these results an has believe that none of these tests is definitive in diagnosis of bacterial meningitis in children.

Characterization of a dopaminergic receptor that modulates adrenomedullary catecholamine release

Nicotine evokes the release of catecholamines from bovine adrenal glands perfused with oxygenated Krebs-bicarbonate solution. Two 2-min pulses of 5 microM nicotine, at 40-min intervals (S1 and S2), gave net catecholamine outputs of 45.2 +/- 3.6 and 29.1 +/- 3.5 micrograms/8 min, respectively. Apomorphine (1 or 10 microM) markedly inhibited catecholamine release during S2 to 9.1 +/- 2.2 and 0.5 micrograms/8 min, respectively. Haloperidol (0.5 microM) reversed the inhibitory effects of apomorphine. Haloperidol alone enhanced catecholamine release induced by nicotine to 67.9 +/- 7.9 micrograms/8 min. [3H]Spiperone binds to adrenomedullary membranes with a KD of 0.24 nM and a Bmax of 117 fmol/mg of protein. Whereas spiperone and haloperidol potently displaced such binding, 3,4-dihydroxyphenylethylamine (dopamine) and sulpiride were poorer displacers, and SCH23390, prazosin, phenoxybenzamine, propranolol, BAY-K-8644, and nitrendipine did not displace [3H]spiperone bound. These data strongly suggest that, as in the cat, the bovine adrenal medulla chromaffin cell contains a dopaminergic receptor that modulates the catecholamine secretory process triggered by stimulation of the nicotinic cholinoceptor. Such a receptor seems to be of the D2 type and might be involved in a sympatho-adrenal cooperative mechanism contributing to the maintenance of cardiovascular homeostasis during stressful situations as well as to the pathogenesis of hypertension. If so, selective dopaminergic agonists might prove clinically useful in the treatment of hypertension.

[Fetal rhabdomyomatous nephroblastoma: study of 2 cases and review of the literature]

Report of two cases of Fetal Rhabdomyomatous Nephroblastoma, a cytodifferentiated variant of Wilms' tumor. The incidence of this rare variant is of 2.10% in our material (88 nephroblastomas in a sixteen years period). The patients were ten months and two years old. Bilateral tumors were discovered in both patients. Preoperative radiotherapy was given but no reduction of the tumors size was obtained. Microscopically, benign looking striated muscle is the predominant component of the tumors, with scare foci of epithelial elements. The low age of presentation, high incidence of bilaterality and the peculiar intrapelvic renal growth are three relevant characteristics in the 35 cases previously reported as well as in these two new cases, that distinguish Fetal Rhabdomyomatous Nephroblastoma from conventional Wilms' tumor.

Evidence for the direct effect of vasopressin on human and goat cerebral arteries

The effects of vasopressin on the cerebral circulation were studied in conscious goats and in isolated human and goat cerebral arteries. Infusion of 1 to 12 mU of vasopressin into the internal maxillary artery of unanesthetized goats caused dose-dependent reductions in cerebral blood flow, a decrease of 36 +/- 4.7% (mean +/- S.E.) occurring with the highest dose. Cumulative application of vasopressin (10(-12) to 10(-6) M) markedly constricted human and goat cerebral arteries in vitro, the effect being more prominent in human vessels. (1-Deaminopenicillamine, 4-valine)-8-D-arginine-vasopressin, a competitive antagonist of the pressor effects of vasopressin, partially inhibited the cerebral vasoconstriction produced by vasopressin in vivo and in vitro without affecting the vasoconstrictor responses to norepinephrine, 5-hydroxytryptamine and potassium chloride. The results indicate that low concentrations of vasopressin produce constriction of cerebral vessels by direct excitatory effects on specific receptor sites. This effect should be considered in certain pathophysiological states in which vasopressin is released in amounts that could interfere with the proper blood supply to the brain.

Cerebrovascular responses to CO2 after inhibition of sympathetic activity

The effects of inhalation of 10% CO2 in air on cerebral blood flow (CBF) and cerebrovascular resistance (CVR) were examined in 13 unanesthetized goats before and after impairment of the sympathetic activity present in cerebral vessels. Under control conditions, inhalation of CO2 increased CBF from 112 +/- 10.2 (SE) to 191 +/- 17.2 ml X min-1 X 100 g-1 and decreased CVR from 0.91 +/- 0.02 to 0.55 +/- 0.03 Torr X ml-1 X min X 100 g. After treatment with reserpine CO2 increased CBF to levels similar to those before treatment, but values for CVR were significantly lower. Inhalation of CO2 1-2 days after removal of both superior cervical sympathetic ganglia produced a larger increase in CBF and a greater drop in CVR, whereas at 6-20 days after ganglionectomy the effects of CO2 were analogous to those measured before the operation. The results suggest that the existence of an intact tonic adrenergic activity is a factor in the level of CVR achieved in hypercapnic acidosis.

Reduction of cerebrovascular reactivity during hypercapnia

The effects on cerebral blood flow of alpha- or beta-adrenergic receptor stimulation of cerebral vessels were examined in 13 unanesthetized goats before and during hypercapnia produced by inhalation of 10% CO2 in air. This procedure increased the PCO2 from 34 to 52 and was accompanied by a fall in pH from 7.39 to 7.26. Electrical stimulation of the cervical sympathetic nerve and injections of norepinephrine and tyramine into the internal maxillary artery produced reductions in cerebral blood flow that were abolished or reduced in hypercapnia. The increase in cerebral blood flow in response to beta-adrenergic stimulation with isoproterenol was also reduced. Hypercapnia caused a similar depression of the constrictor and dilatory effects of the nonadrenergic drugs vasopressin and diazoxide. The results show a decreased response of cerebral vessels to adrenergic and nonadrenergic stimuli in hypercapnia. The findings do not suggest any difference between the refractoriness of cerebral vessels in hypercapnia and that described in other vascular beds.

Sulfobromophthalein clearance tests before and after ethinyl estradiol administration, in women and men with familial history of intrahepatic cholestasis of pregnancy

To test the hypothesis that intrahepatic cholestasis of pregnancy represent an abnormal reaction to estrogens in genetically predisposed individuals, the sulfobromophthalein disappearance curve from blood was compared before and after ethinyl estradiol administration (0.1 mg/day, during 6 days) in multiparous women with or without a past history of intrahepatic cholestasis of pregnancy, and in nulliparous women and men with or without a familial history of the disease. BSP concentration in blood, from 5 to 65 min after a single i.v. injection of the dye (5 mg/kg body wt), was fitted into biexponential curves using a computerized program. Ethinyl estradiol administration decreased the slope of the second component of the curve (k2) in most subjects and in both sexes. This effect was greater in multiparous women with a past history of intrahepatic cholestasis of pregnancy than in their controls. An exaggerated response to ethinyl estradiol was more frequently found in nulliparous women, and in men, with a familial history of the disease than in those without it. These observations suggest the presence of a constitutional abnormality in the metabolic interactions between estrogens and the liver, independent from pregnancy itself. This abnormality could be genetically transmitted by individuals from either sex, determining a predisposition to develop intrahepatic cholestasis of pregnancy in their female descendants.

[Wilms' tumor: a series of 79 cases (author's transl)]

79 cases of Wilms' tumor with age at diagnosis between 0 and eight years, are reported. 76 of them are evaluable for therapeutic results. 54 (71%) are alive and disease-free, with a mean survival of 53 months. Group A (35 patients) received pre-surgical treatment with radiotherapy and the survival rate is 77%. Group B (32 patients) were not treated before surgery and the survival rate is 84%. Both groups received post-surgical treatment with radiotherapy and chemotherapy (vincristine and actinomycin D). Patients in group C, chronologically the oldest, did not receive chemotherapy and its survival rate was 20%. Prognostical significance of age, sex, site, clinical stage and histology are examined. Classical concepts on histological classifications are revised and present criteria are shown, along with its' therapeutic and prognostic implications.

Immunity to antigenically related salmonellae: effects of humoral factors on the bactericidal activity of normal and immune peritoneal exudate cells

Immunity against Salmonella enteritidis and Listeria monocytogenes was studied by measuring in vitro the bactericidal activity of peritoneal exudate cells (PEC) of control (normal PEC) and S. typhi Ty2-immune (immune PEC) mice. Specific immune serum, anti-S. tyhphi Ty2, heat inactivated at 56 degrees C for 30 min, significantly inhibited the growth of S. enteritidis only with immune PEC. These opsonic factors had no effect upon the activity of normal PEC. That such inhibition could not be demonstrated in Listeria experiments, either with immune or normal PEC, suggests that S. enteritidis was specifically recognized, in vitro, by the thermostable opsonin anti-S. typhi Ty2 and that macrophages from immune PEC were more efficient in inhibiting bacterial growth than those from normal PEC. Thus, the interaction between macrophages and the microorganism seems to play an essential role in cell-mediated as well as humoral immunity.

[Rhabdomyosarcoma in childhood. Report of 27 cases (author's transl)]

Twenty-seven cases of rhabdomyosarcoma in children between one month and 14 years of age are reported. The most frequent histologic type was the embryonal sarcoma and almost half of the cases were diagnosed in advanced clinical stages. Treatment consisted on the combination of surgery, radiotherapy and chemotherapy (vincristine, cyclophosphamide and actinomicin-D in non metastatic cases, plus adriamycin when metastases were present). The survival rate is 57.7% and the survival with no evidence of disease 53.8%, with observation periods from eight months to four years.

["Cellular synchronization" method in treatment of infantile tumors]

Results obtained by the "cellular synchronization" method in 19 patients are reported; there were five Ewing's sarcomas, three nephroblastomas, nine neuroblastomas and two Burkitt lymphomas. Ages ranged between four months and six years. Most of them had metastatic diseases, resistent to previous therapies. The protocol consisted on vincristine as "synchronizator agent" days 1 and 2, and cyclophosphamide as "effector agent", days 3, 4, 5 and 6 of each pulse. The clinical and hematologic tolerance was generally good. Results were: 12 complete remissions, two partial remissions and three failures.

[Treatment of Ewing's tumor (author's transl)]

Eight cases of Ewing's tumor are reported. Four cases (50%) were localized forms at diagnosis and the remaining presented metastasis. The localized forms were treated with a combination of irradiation at dose of 4,500-5,000 rads and chemotherapy with vincristine and cyclophosphamide during two years. Three of these patients (75%) are alive and free of disease for more than two years. In the metastatic forms the treatment used was radiotherapy and diverse chemotherapy combinations with palliative intention. Bibliography related with this subject is reviewed and new chemotherapeutic combinations are discussed, the superiority of any treatment being not yet established.