Inhibition of monoacylglycerol lipase mediates a cannabinoid 1-receptor dependent delay of kindling progression in mice.

Endocannabinoids, including 2-arachidonoylglycerol (2-AG), activate presynaptic cannabinoid type 1 receptors (CB1R) on inhibitory and excitatory neurons, resulting in a decreased release of neurotransmitters. The event-specific activation of the endocannabinoid system by inhibition of the endocannabinoid degrading enzymes may offer a promising strategy to selectively activate CB1Rs at the site of excessive neuronal activation with the overall goal to prevent the development epilepsy. The aim of this study was to investigate the impact of monoacylglycerol lipase (MAGL) inhibition on the development and progression of epileptic seizures in the kindling model of temporal lobe epilepsy. Therefore, we selectively blocked MAGL by JZL184 (8mg/kg, i.p.) in mice to analyze the effects of increased 2-AG levels on kindling acquisition and to exclude an anticonvulsive potential. Our results showed that JZL184 treatment significantly delayed the development of generalized seizures (p=0.0066) and decreased seizure (p<0.0001) and afterdischarge duration (p<0.001) in the kindling model of temporal lobe epilepsy, but caused only modest effects in fully kindled mice. Moreover, we proved that JZL184 treatment had no effects in conditional CB1R knockout mice lacking expression of the receptor in principle neurons of the forebrain. In conclusion, the data demonstrate that indirect CB1R agonism delays the development of generalized epileptic seizures but has no relevant acute anticonvulsive effects. Furthermore, we confirmed that the effects of JZL184 on kindling progression are CB1R mediated. Thus, the data indicate that the endocannabinoid 2-AG might be a promising target for an anti-epileptogenic approach.

Analysis in conditional cannabinoid 1 receptor-knockout mice reveals neuronal subpopulation-specific effects on epileptogenesis in the kindling paradigm.

The endocannabinoid system serves as a retrograde negative feedback mechanism. It is thought to control neuronal activity in an epileptic neuronal network. The purpose of this study was to evaluate the impact of the endocannabinoid and endovanilloid systems on both epileptogenesis and ictogenesis. Therefore, we modulated the endocannabinoid and endovanilloid systems genetically and pharmacologically, and analyzed the subsequent impact on seizure progression in the kindling model of temporal lobe epilepsy in mice. In addition, the impact of seizures on associated cellular alterations was evaluated. Our principal results revealed that the endocannabinoid system affects seizure and afterdischarge duration dependent on the neuronal subpopulation being modulated. Genetic deletion of CB1-receptors (CB1Rs) from principal neurons of the forebrain and pharmacological antagonism with rimonabant (5 mg/kg) caused longer seizure duration. Deletion of CB1R from GABAergic forebrain neurons resulted in the opposite effect. Along with these findings, the CB1R density was elevated in animals with repetitively induced seizures. However, neither genetic nor pharmacological interventions had any impact on the development of generalized seizures. Other than CB1, genetic deletion or pharmacological blockade with SB366791 (1 mg/kg) of transient receptor potential vanilloid receptor 1 (TRPV1) had no effect on the duration of behavioral or electrographic seizure activity in the kindling model. In conclusion, we demonstrate that endocannabinoid, but not endovanilloid, signaling affects termination of seizure activity, without influencing seizure severity over time. These effects are dependent on the neuronal subpopulation. Thus, the data argue that the endocannabinoid system plays an active role in seizure termination but does not regulate epileptogenesis.

Enhanced cancer growth in mice administered daily human-equivalent doses of some H1-antihistamines: predictive in vitro correlates.

BACKGROUND: Present studies of drug-induced tumor growth promotion have evolved from earlier investigations into the mechanism of action of N,N-diethyl-2-[4-(phenylmethyl)phenoxy[ethanamine.HCl, a tamoxifen derivative which potently inhibits lymphocyte mitogenesis in vitro and stimulates tumor growth in vivo. It is thought that potency to bind to intracellular histamine receptors (HIC), some of which are on cytochromes P450, may correlate with tumor growth-promoting activity. PURPOSE: We assessed the effectiveness of five in vitro assays in predicting in vivo tumor growth stimulation by the H1-antihistamines loratadine, astemizole, cetirizine, hydroxyzine, and doxylamine. METHODS: Potency of each agent was ranked 1-5 in each of the following in vitro assays: 1) inhibition of [3H]histamine binding to microsomal HIC, 2) inhibition of histamine binding to microsomal P450, 3) inhibition of the P450-catalyzed demethylation of aminopyrine, 4) inhibition of lymphocyte mitogenesis, and 5) stimulation of tumor colony formation. An overall rank score was assigned to each drug and correlated with tumor growth stimulation in vivo. Two laboratories conducted in vivo studies in a blinded fashion. Female C57BL and C3H mice were given a subcutaneous injection on day 1 of syngeneic B16F10 melanoma cells (5 x 10(5)) or C-3 fibrosarcoma cells (1 x 10(5)), respectively. Mice were randomly assigned to treatment groups, then received a single, daily intraperitoneal injection of an estimated human-equivalent dose (or range of doses) of antihistamine or vehicle control for 18-21 days before being killed. Tumors were surgically removed and wet weights compared statistically among groups. RESULTS: The cumulative potency of each drug in affecting tumor growth or growth mechanisms in the five in vitro assays ranked as follows: Loratidine and astemizole ranked highest and were equally potent, followed in decreasing order by hydroxyzine, doxylamine, and cetirizine. A significant correlation (r = .97; P < .02) was observed between the rank order of potency of the antihistamines in all five in vitro assays and the rank order to enhance tumor growth in vivo: Loratidine and astemizole significantly (P < .001) promoted the growth of both melanoma and fibrosarcoma, hydroxyzine significantly (P < .001) promoted the growth of melanoma, while doxylamine and cetirizine did not promote the growth of either tumor. CONCLUSION: Data demonstrate that the in vitro assays predicted the propensity of each H1-antihistamine to stimulate cancer growth in vivo. IMPLICATION: These in vitro tests may prove valuable to screen potential tumor growth promoters.

Histamine and growth: interaction of antiestrogen binding site ligands with a novel histamine site that may be associated with calcium channels.

N,N-Diethyl-2-[(4-phenylmethyl)-phenoxy]ethanamine hydrochloride (DPPE) is a novel paradiphenylmethane derivative with antiproliferative and antiestrogenic properties. Like tamoxifen (TAM), DPPE binds to the microsomal antiestrogen binding site with high affinity (Kd approximately 50 nM), but, conversely, not to estrogen receptor or calmodulin. We now demonstrate that DPPE competes for [3H]histamine binding in rat cerebral cortex with an affinity (Ki = 4.5 +/- 2.6 X 10(-6) M) significantly greater than that of the H1 antagonist pyrilamine (Ki = 7.2 +/- 2.2 X 10(-5) M), despite the previous demonstration that pyrilamine is up to 1000 times more potent than DPPE in antagonizing histamine-induced contraction in canine tracheal smooth muscle. DPPE demonstrates antiproliferative activity against MCF-7 cells at concentrations between 1 X 10(-7) and 1 X 10(-5) M; the IC50 value of DPPE for growth inhibition at 7 days in this assay is 5 X 10(-6) M, a value equivalent to its Ki value for histamine binding. DPPE also competes for [3H]verapamil binding in membranes from whole rat brain with an affinity equal to that for verapamil (Kd = 4.0 +/- 1.8 X 10(-7) M); however, verapamil competes for [3H]DPPE binding in brain membranes and rat liver microsomes with an affinity markedly lower (Ki approximately 1 X 10(-4) M) than that of DPPE, suggesting allosteric interactions between the verapamil and DPPE sites. Unlike DPPE, verapamil is not antiproliferative in vitro against MCF-7 cells at concentrations up 1 X 10(-5) M, but, like DPPE, is cytotoxic at concentrations of 1 X 10(-4) M. In immature oophorectomized rats, verapamil or DPPE alone is antiuterotropic; however, verapamil shows no antagonism of exogenous estradiol on uterine growth, as opposed to DPPE which is a partial antagonist. Thus, the antiproliferative and antiestrogenic properties of DPPE either are not associated with calcium channel antagonism, or result from a qualitatively different effect on channels than verapamil. The in vitro antiproliferative effect of DPPE (7.5 X 10(-6) M) on MCF-7 cells at 72 h is significantly reversed by 10 mM L-histidine (70.2 +/- 12.6% reversal) and L-methionine (92.4 +/- 11.1% reversal), but not by L-ornithine, L-arginine, L-phenylalanine, or exogenous histamine. At lower concentrations of TAM (0.75 X 10(-6) M), where growth inhibition is estrogen-reversible, L-ornithine, but not L-histidine or L-methionine, causes significant reversal of growth inhibition (66.8 +/- 13.3%; p less than 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)

Correlation of the antiproliferative action of diphenylmethane-derivative antiestrogen binding site ligands with antagonism of histamine binding but not of protein kinase C-mediated phosphorylation.

The nonestrogen receptor-mediated antiproliferative action of antiestrogen binding site (AEBS) ligands, including triphenylethylene antiestrogens and phenothiazines, has been linked to their ability to inhibit protein kinase C (PKC). Recent studies indicate that some diphenylmethane derivatives inhibit growth, are potent AEBS ligands, and antagonize histamine binding at an AEBS-related histamine site different from H1 and H2. Three novel diphenylmethane derivatives, N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine.HCI (DPPE), 4-decanoyl-DPPE (dec-DPPE), and 4-benzylphenyl decanoate (BPD) were studied in an attempt to determine whether PKC or histamine interactions best correlate with their antiproliferative effects. Platelet aggregation and the phosphorylation of a platelet Mr 47,000 protein (p47) induced by phorbol-12-myristate-13-acetate (PMA) represent two processes mediated by PKC. DPPE inhibits PMA-induced aggregation [50% inhibitory concentration (IC50) = 31.2 +/- 2.4 (SEM) x 10(-6) M] but does not significantly inhibit either PMA-induced phosphorylation of Mr 47,000 protein (IC50 greater than 500 x 10(-6) M), or binding of [3H]phorbol dibutyrate to platelets. dec-DPPE is a more potent inhibitor of PMA-induced platelet aggregation (IC50 = 18.8 +/- 0.7 x 10(-6) M), a weak inhibitor of Mr 47,000 phosphorylation (IC50 = 80-200 x 10(-6) M), but is without effect on [3H]phorbol dibutyrate binding. BPD, which lacks the alkylaminoethoxy side chain necessary for binding to the AEBS/DPPE site, is devoid of anti-PMA effects. These results are compared to the inhibition of [3H]histamine binding in rat cortex membranes (Ki value for DPPE = 0.83 +/- 0.62 x 10(-6) M; Ki value for dec-DPPE = 6.6 +/- 3.5 x 10(-6) M; BPD is inactive) and growth inhibition of MCF-7 cells (IC50 value for DPPE = 4.5 x 10(-6) M; IC50 value for dec-DPPE = 1.5 x 10(-5) M; BPD is ineffective at all concentrations tested). Thus, while dec-DPPE is a more potent inhibitor of PKC-mediated phosphorylation, DPPE is a more potent inhibitor of histamine binding and is correspondingly more antiproliferative than dec-DPPE. The results support a relationship between antagonism of histamine binding and growth inhibition but argue against an association between the antiproliferative effects of DPPE and dec-DPPE and inhibition of PKC. The findings for DPPE suggest that platelet response to PMA, antagonized by diphenylmethane-type AEBS-ligands, may be mediated, at least in part, by mechanisms other than activation of protein kinase C-dependent phosphorylation.

Stimulation of malignant growth in rodents by antidepressant drugs at clinically relevant doses.

Tricyclic antidepressants, such as amitriptyline (Elavil), and the nontricyclic agent, fluoxetine (Prozac), bind to growth-regulatory intracellular histamine receptors, associated with anti-estrogen binding sites in microsomes and nuclei. The prototype anti-estrogen binding site/intracellular histamine receptor ligand, N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine HCl, inhibits normal cell proliferation in vitro but stimulates tumor growth in vivo. Because of their structural similarity to N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine HCl, we carried out studies to determine whether amitriptyline and fluoxetine stimulate tumor growth and/or development in rodents at concentrations relevant to the treatment of human depression (equivalent human dose range, approximately 100-150 mg/day for amitriptyline and approximately 20-80 mg/day for fluoxetine). All experiments were performed blinded. In studies of growth stimulation of transplantable syngeneic tumors, groups of mice were inoculated s.c. with C-3 fibrosarcoma cells or given i.v. or s.c. injections of B16f10 melanoma cells, followed 24 h later by daily i.p. injections of saline, amitriptyline, or fluoxetine. Tumor latency (fibrosarcoma), aggregate tumor weight (s.c. injected melanoma), or time to death from pulmonary metastasis (i.v. injected melanoma) was determined; drug-induced stimulation of DNA synthesis in C-3 fibrosarcoma cells in vitro was correlated with tumor growth acceleration in vivo. In a mammary carcinogenesis model, the effects of chronic saline, amitriptyline, or fluoxetine administration on the rate and frequency of development of mammary tumors in rats fed dimethylbenzanthracene (DMBA) were compared. Eight of 20 amitriptyline- or fluoxetine-treated mice developed fibrosarcoma tumors by day 5, as compared to none of 20 saline controls (P less than 0.002). Similarly, 20 of 21 DMBA-treated rats receiving the antidepressant drugs developed 33 mammary tumors by week 15 as compared to 5 tumors in 4 of 7 DMBA-treated rats receiving saline (P less than 0.001). For both models, tumor latency decreased 30-40% and, in the DMBA model, tumor frequency increased greater than 2-fold in the antidepressant-treated rats as compared to controls. Stimulation of fibrosarcoma growth in vivo correlated with a corresponding bell-shaped drug-induced increase in DNA synthesis in vitro. While the median time to death from pulmonary metastases did not differ among groups given i.v. injections of melanoma cells, a significant (P less than 0.01) stimulation of growth of s.c. injected melanoma was observed in mice receiving the antidepressants.(ABSTRACT TRUNCATED AT 400 WORDS)

The antiproliferative properties of tamoxifen and phenothiazines may be mediated by a unique histamine receptor (?H3) distinct from the calmodulin-binding site.

N,N-diethyl-2-[(4-phenylmethyl)-phenoxy]-ethanamine HCl (DPPE), a novel histamine antagonist (?H3), which selectively binds with high affinity to the antiestrogen-binding site (AEBS/?H3), inhibits the activity of calmodulin-dependent myosin light chain kinase (MLCK) only at concentrations greater than 1 mM, as opposed to tamoxifen (TAM), which has an IC50 = 4 microM in the same assay. This suggests that the antiestrogen-binding site is distinct from the site on calmodulin which binds TAM and phenothiazines. However, at an in vitro concentration of 1 X 10(-6) M, the antiproliferative effects of DPPE and several phenothiazines, which also compete for binding to AEBS/?H3, are about equal; this suggests that affinity for AEBS/?H3 rather than that for the calmodulin-binding site may correlate with clinically relevant antigrowth effects of these compounds.

Dental abnormalities in Schimke immuno-osseous dysplasia.

Described for the first time in 1971, Schimke immuno-osseous dysplasia (SIOD) is an autosomal-recessive multisystem disorder that is caused by bi-allelic mutations of SMARCAL1, which encodes a DNA annealing helicase. To define better the dental anomalies of SIOD, we reviewed the records from SIOD patients with identified bi-allelic SMARCAL1 mutations, and we found that 66.0% had microdontia, hypodontia, or malformed deciduous and permanent molars. Immunohistochemical analyses showed expression of SMARCAL1 in all developing teeth, raising the possibility that the malformations are cell-autonomous consequences of SMARCAL1 deficiency. We also found that stimulation of cultured skin fibroblasts from SIOD patients with the tooth morphogens WNT3A, BMP4, and TGFß1 identified altered transcriptional responses, raising the hypothesis that the dental malformations arise in part from altered responses to developmental morphogens. To the best of our knowledge, this is the first systematic study of the dental anomalies associated with SIOD.

Testicular function following cyclophosphamide treatment for childhood nephrotic syndrome: long-term follow-up study.

Testicular function of 17 males treated in childhood or adolescence for nephrotic syndrome (NS) with cyclophosphamide (CY) for a mean time of 240 days (mean total dosage of 16.4 g or 641 mg/kg body weight) was evaluated at a mean time of 11.8 years after treatment. Five were azoospermic, 1 oligospermic, and 11 normospermic. There was a significant inverse correlation of sperm density with CY dosage and duration of treatment. All patients had undergone normal pubertal development and had normal sexual characteristics. Both basal and gonadotropin-releasing hormone-stimulated follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations were significantly raised in oligo- and azoospermic patients. Raised basal and peak FSH and LH concentrations in normospermic patients with a sperm count of less than 40 x 10(6)/ml were in keeping with impairment of two testicular components. However, mean basal plasma testosterone levels and mean peak plasma testosterone responses to human chorionic gonadotropin (HCG) did not differ significantly between patients and controls. Although LH responses to gonadotropin-releasing hormone suggested compensated Leydig cell failure in patients with testicular tubular damage, secretory reserve capacity of these cells, estimated by a HCG stimulation test, was preserved. Further follow-up is required to ascertain whether in these patients Leydig cell failure will develop with time.

Pituitary-gonadal function in women following cyclophosphamide treatment for childhood nephrotic syndrome: long-term follow-up study.

Ovarian and pituitary-gonadal function was evaluated in 12 women who were treated with cyclophosphamide for nephrotic syndrome before or during puberty. The mean age at the start of treatment was 8.7 years; the mean total dose of cyclophosphamide was 439 mg/kg body weight; and the mean follow-up time was 12.3 years. The investigations included detailed developmental, menstrual and fertility histories; general and gynaecological examinations; basal levels and follicle-stimulating hormone and luteinizing hormone responses to gonadotropin-releasing hormone, and plasma oestradiol determinations. All patients had normal pubertal development and regular menstrual patterns. Two had borne healthy children. Although hormonal studies did not show obvious ovarian or pituitary-gonadal dysfunction, further follow-up is required to ascertain whether the patients with the most prolonged treatment undergo a premature menopause.

New evidence that the antiestrogen binding site may be a novel growth-promoting histamine receptor (?H3) which mediates the antiestrogenic and antiproliferative effects of tamoxifen.

Using as a probe [3H]-DPPE (N,N-diethyl-2-[(4-phenylmethyl)phenoxy]ethanamine HCl), a novel compound selective for the antiestrogen binding site (AEBS), new evidence is presented that this site could be a growth-promoting histamine receptor of a type not previously described (?H3). In the rat uterus, DPPE alone at a concentration of 4 mg/kg acts as an estrogen antagonist, unlike TAM alone which is a partial estrogen agonist. In the presence of exogenous estradiol, both TAM and DPPE are partial antagonists. This suggests that the "antiestrogenic" effects of tamoxifen are mediated through AEBS/?H3 while the estrogenic effects are mediated through ER.

[Drug therapy of vesico-ureteral reflux in children]. / Medikamentna terapija vezikoureternog refluksa kod dece.

The results of medical management of primary vesicoureteric refluc in 138 children aged 3 months to 15 years are presented. All children were kept on long-term, low-dose continuous chemoprophylaxis of urinary tract infection. During the 2-6 years follow-up period serial urine cultures, interval radiographic revaluation, renal function tests and blood pressure measurements were performed. Refluc disappeared spontaneously in 91 patients (66%), persisted in 9.4% and was later on surgically corrected in 20% of children. The refluc grade at presentation was the most important factor affecting the outcome: the refluc disappeared from 72% of affected ureters with grade I and II, and from 28% of ureters with grade III and IV. The presence of renal scaring and recurrence of urinary tract infection during the chemophylaxis did not influence the percentage of cured patients. Nevertheless, the mean duration of refluc from diagnosis to its spontaneous resolution was significantly longer in children with renal scars and urinary tract infections compared with its duration in children who had neither scars, nor further infections. Renal scarring progressed in 2.8% patients. Chronic renal failure developed, in spite of spontaneous resolution of refluc, in only one child with hypertension and bilateral renal scars at presentation. It is concluded that medical treatment of vesicoureteric refluc in most of the children is successful and in regard of preserving renal function stage.

Recurrent haemolytic-uraemic syndrome with hypocomplementaemia: a case report.

A boy who developed haemolytic-uraemic syndrome (HUS) at 8 years 6 months of age had four further episodes of the disease during the next 3 years. No renal abnormalities were detected between the attacks nor in the 2.5 years after the last recurrence. Reduced levels of serum complement were found during four of the episodes and in two intervening periods.

Cyclophosphamide-induced sister chromatid exchanges in patients with nephrotic syndrome.

Frequency of sister chromatid exchanges (SCE) of peripheral blood lymphocytes was used for assessing chromosome damage induced by cyclophosphamide (CY) in patients with primary nephrotic syndrome. A significant rise in SCE was seen in all patients on a standard 6- to 8-week CY regimen at the beginning of the first week of treatment. When CY was discontinued, a gradual decline in SCE was noted which returned to a normal limit within 4-6 months after discontinuation of the drug. In patients treated previously (mean follow-up 9.6 years, range 1.5-17.5 years) with high doses of CY (mean total dose 380 mg/kg, range 120-1,999) or in patients on steroid therapy, frequency of SCE was not significantly different from control subjects. We concluded that SCE analysis did not reveal any evidence suggesting that the dosage of CY used in this study had induced a permanent genetic damage. However, further follow-up of patients who had received the largest total doses of drug is required.

[Percutaneous biopsy of the kidney in children: indications, results, and complications]. / Perkutana biopsija bubrega kod dece: indikacije, rezultati i komplikacije.

The authors present results of systematic use of percutaneous renal biopsy in children in the first three years of practice. From 1986 to 1989, 153 renal biopsies were done in 144 children and adolescents (75 males, 69 females) aged 4 months to 18 years. The most common indications were as follow: primary nephrotic syndrome, most often resistant to corticosteroid treatment (28.5%), haematuria (28.5%), secondary glomerulopathies, either with or without nephrotic syndrome (9.7% and 15.3%, respectively), and proteinuria (4.9%). 90.8% of biopsies were successful obtaining adequate tissue for light microscopic diagnosis, containing a n average number of 16 glomeruli. An overall number of 29 complications (18.9% of biopsies) in 23 patients was observed. Gross haematuria was the most common, lasting no more then one (9.8% of biopsies) or three days (2.6%) requiring blood transfusions in three cases (1.96% of biopsies). Others complications were fever (1.96%), perirenal haematoma (1.3%), and severe pain at the site of biopsy (1.3%). There were no significant differences between three annual periods with regard to the incidence of successful biopsies or complications, but more serious complications occurred during the first year of practice. In children younger than five years the rate of successful biopsies was higher and incidence of complications was lower than in older children. The authors' results correlate favourably with data published in the foreign literature.

Does intracellular histamine mediate mast cell histamine release?

Previously, we demonstrated that through binding a novel intracellular receptor of microM affinity (HIC), histamine mediates, and the HIC antagonist N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine. HCl (DPPE) inhibits, platelet aggregation and serotonin granule secretion; the latter response is dependent upon the same processes that mediate histamine release from mast cell granules. We now show that, as for platelet serotonin release, DPPE blocks concanavalin A-stimulated mast cell histamine release with a potency (IC50 = 30 microM) greater than the H1-antagonist, pyrilamine (IC50 = 150 microM) or the H2-antagonist cimetidine (IC50 = 5 mM), correlating with rank order of potency to inhibit 3H-histamine binding in rat brain membranes and liver microsomes. We postulate that histamine release from mast cells is mediated at HIC by second messenger intracellular histamine. However, unlike platelets, mast cells do not appear to rely on newly synthesized histamine. Rather, as for calcium, histamine may be mobilized from bound stores to mediate histamine secretion.

[Acute tubulointerstitial nephritis in children]. / Akutni tubulointersticijumski nefritis kod dece.

UNLABELLED: Acute tubulointerstitial nephritis (ATIN) is a rare renal disorder in children. Patients usually present non-specific symptoms and signs so that the diagnosis of ATIN is often delayed. The disease may be infection- or drug-induced or it may occur without a known cause. Early recognition and appropriated therapy usually lead to an excellent prognosis. The aim of the study was to describe clinical and laboratory findings and the course of ATIN in 21 patients, that are typical enough to enable early recognition of the disease as it is potentially reversible. METHODS: Between 1986 and 1997 we observed 21 patients, aged 7-16 years (mean, 12.8), with acute tubulointerstitial nephritis, including eight with tubulointerstitial nephritis and uveitis (TINU syndrome). Laboratory studies included urinalysis, complete blood count, erytrocyte sedimentation rate (ESR), plasma creatinine, glomerular filtration rate (GFR), electrolytes, proteins, IgG, C3, C4 antinuclear-antibodies (ANA), antistreptolysin-O and antibodies to hantaviruses. Renal ultrasound was done in all patients. Renal biopsy was performed in 5 children. RESULTS: All children had previously been healthy. The symptoms of ATIN developed within a few days (Table 1). The most common initial symptoms were fatigue, fever, gastrointestinal disturbances, anorexia and weight loss. Less common complaints included headache, arthralgias and maculopapular rash. On addmition no patient had hypertension, oedema or evidence of acute infection. ESR, plasma urea and creatinine concentrations were increased in all, plasma proteins and IgG levels in the majority of patients. ANA were negative in 15 pts in whom this analysis was performed; C3 and C4 levels were normal. In two children recent strepococcal and in the other 6 hantavirus infection was serologicaly proved. All patients had non-oliguric acute renal failure (ARF): GFR was 21.7 +/- 8 9 in 14 pts and 67 +/- 9.7 in 7 pts. Low urine specific gravity (1003-1014), mild proteinuria (0.3-0.4 g/24 h), leukocyturia and/or haematuria were found in all patients; glycosuria, aminoaciduria and decreased tubular reaposrption of phosphate (TRP) were found in 12/21, 9/21 and 9/14 patients, respectively. Urine cultures were negative in all children. Renal US demonstrated enlarged hyperechoic kidneys in 11 pts, in remaining 10 pts no abnormalities were found. Renal biopsy, performed in 5 children, confirmed the diagnosis of ATIN. Eight patients subsequently developed anterior uveitis as part of TINU syndrome. Treatment included supportive therapy in all and six patients received prednisolone for 4-8 weeks (40-60 mg/m2/24 h for 10-14 days with subsequent reduction of dose over several weeks). Anterior uveitis was successfully treated with topical steroids. Renal function completely recovered in all patients: GFR (109 +/- 22.6 ml/min) within a mean interval of 47 +/- 33 days, concentration ability within 2-12 (mean 4.5) months. DISCUSSION: Common clinical features of ATIN are non-oliguric acute renal failure of various degrees, signs of tubular dysfunction, proteinuria, haematuria, leukocyturia and absence of hypertension. All our patients had normal blood pressure, non-oliguric renal failure, proteinuria, hypostenuria and abnormal urinary sediment; about half of them had glycosuria and/or other signs of proximal tubular dysfunction. The most important causes of ATIN in children reported in literature are systemic infections and drugs. However, the cause of ATIN in our patients was assessed as being related to infection only in 8 patients and to diclofenac in one. No infection, drug, toxin or other cause could be identified in 4, as well as in 8 pts with TINU syndrome. The prognosis of ATIN in children is considered to be favourable, but some patients may develop chronic renal failure. Renal function completely recovered in all our patients; that is consistent with outcome data from the most reports. CONCLUSION: Acute tubulointerstitial nephritis is an important cause of ARF in children, its aetiology may be different and it carries an excellent prognosis. ATIN should be suspected in a child who presents typical, although non-specific symptoms and signs, associated with lukocyturia and/or microhaematuria, signs of tubular dysfunction and unexplained renal failure. The diagnosis can be verified at renal biopsy. Early recognition of the disease is important to remove possible aetiologic agents and to treat them before chronic lesions are present to avoid long-term renal damage.

[Belgrade and Hantaan hantaviruses--the causative agents of haemorrhagic fever with renal syndrome in children in Serbia]. / Hantavirusi Beograd i Hantan--uzrocnici hemoragijske groznice s bubreznim sindromom kod dece u Srbiji.

During an outbreak of haemorrhagic fever with renal syndrome (HFRS) in 1989, five children (3 girls, 2 boys, aged 6.8-16 years) with severe clinical form of the disease, were treated at the Institute of Mother and Child Health of Serbia; four of them were followed-up 22-28 months thereafter. The main clinical features were: fever, headache, myalgia, abdominal and back pains, and vomiting in all, and haemorrhagic syndrome in three; renal syndrome with severe acute renal failure in all five patients. All the patients recovered. Serological confirmation by an indirect immunofluorescence assay, enzyme immunoassay for IgM antibodies, and by plaque reduction neutralization test revealed that the infection was caused by Belgrade virus in three, and by Hantaan virus in two patients. It was not possible to differentiate these two serogroups on the basis of clinical features. This finding gave further evidence of circulation of different hantaviruses causing severe HFRS in Serbia.

Evidence that the antiestrogen binding site is a histamine or histamine-like receptor.

N,N-diethyl-2-[(4 phenylmethyl)-phenoxy]-ethanamine X HCl (DPPE), a compound selective for the antiestrogen binding site, is structurally similar to the aminoethyl ether group of antihistamines. Our studies now reveal that H1-, but not H2-antagonists, also compete for this site in the order: DPPE = hydroxyzine = perchlorperazine greater than phenyltoloxamine greater than pyrilamine greater than diphenhydramine. The affinity of these compounds for the antiestrogen binding site correlates with their in vitro cytotoxicity against MCF-7 and EVSA-T human breast cancer cells. Tamoxifen, DPPE and hydroxyzine also bind to H1 receptors present in digitonin-solubilized rat liver microsomes, but with less affinity than pyrilamine, which is selective for this site; the ratio of H1 to antiestrogen binding sites in this preparation is 4:1. The data suggest that the antiestrogen binding site may be, in whole or in part, a receptor for histamine different from H1 and H2.

[Delayed effect of cyclophosphamide on testicular function after treatment of nephrotic syndrome in childhood]. / Udaljeni efekti ciklofosfamida na funkciju testisa posle lecenje nefrotskog sindroma u detinjstvu.

The authors present the results of study of testicular spermatogenetic and endocrine function in adult males treated with high doses of cyclophosphamide for nephrotic syndrome during childhood and/or adolescence. Seventeen males, mean age of 22.5 years (range, 17-30) were examined after mean follow-up of 11.8 (5-17.3) years. Mean age at the time of treatment was 10.8 (3.6-17.6) years; mean duration of cyclophosphamide treatment was 240 (39-701) days, and mean total cumulative doses were 641 mg/kg body weight (103-1999) or 16.4 (3.9-55.7) grams. All the patients undergone normal pubertal development and had normal sexual characteristics. Eleven were normospermic (more than 20 x 10(6)/ml spermatozoa), one oligospermic and five azoospermic. There was a significant inverse correlations of sperm density with cyclophosphamide dosage and duration of treatment. These variables seem to be more important for cyclophosphamide toxicity, than stage of sexual development at time of treatment. Raised basal and stimulated FSH concentrations in oligoazoospermic patients were in keeping with impaired spermatogenesis. These patients had also raised basal and stimulated LH concentrations suggesting compensated Leydig cell failure. Subgroup of normospermic patients with lower spermatozoa concentrations (20-40 x 10(6)/ml) had significantly raised FSH and LH responses on stimulation with gonadotropin releasing hormone, suggesting dysfunction both tubular and interstitial cell component of the testis. In other normospermic patients gonadotropin responses were not different from controls. Basal and HCG stimulated testosterone concentrations showed no differences between patients and controls. These results confirmed significant inverse correlations of cyclophosphamide dosage with its effect on spermatogenesis, and documented the long-term effect on the Leydig cell function requiring further follow-up.