A new approach to determining pharmacologic adulteration of herbal weight loss products.

Pharmaceutical adulterants are commonly found in herbal weight loss products, and analytical techniques for detecting these adulterants have become increasingly important to the public health community. Previously we reported a novel analytical method for the determination of adulterants in herbal formulations by capillary electrophoresis with contactless conductivity detection. The current study refines this previously described technique by testing if anxiolytics, diuretics, and laxatives interfered with the detection of anorectics and antidepressants. A survey of herbal weight loss products sold by compounding pharmacies in Brazil were analysed to determine the presence of pharmaceutical adulterants. A total of 106 herbal products, collected from 73 pharmacies in nine Brazilian states, were analysed for amfepramone, sibutramine, fenproporex, fluoxetine, paroxetine, sertraline and bupropion using the new analytical method. The method permitted the rapid and selective screening for the seven adulterants. Of the 106 weight loss products sampled, four (3.8%) were found to be adulterated by fenproporex or sibutramine. The adulterated samples were compounded by four different pharmacies located in three different Brazilian states. The novel capillary electrophoresis method we developed may be a useful tool for public health organisations tasked with analysing herbal weight loss products.

Bronchoesophageal fistula in a patient with non-Hodgkin's lymphoma.

Bronchoesophageal fistula secondary to lymphoma is a very rare condition, usually associated with chemo-radiotherapy. We report a case of a patient with a non-Hodgkin's lymphoma (NHL) who, after chemotherapy, developed an oesophago-tracheal fistula. Initially it was treated conservatively but due to the lack of response, a stent was inserted. After nearly one year without success, surgery was considered. Right thoracotomy oesophagectomy and closure of the tracheal defect with an intercostal muscle flap and pericardial patch was performed. This was followed by laparoscopic creation of a gastric tube, which was successfully anastomosed to the cervical oesophagus through a cervicotomy. Unlike oesophageal cancer, NHL can have a good prognosis, so curative treatment of the fistula can be considered. Conservative treatment must always be the first option, leaving stenting or surgery for when the problem persists.

Requirement of mitogen-activated protein kinases and I kappa B phosphorylation for induction of proinflammatory cytokines synthesis by macrophages indicates functional similarity of receptors triggered by glycosylphosphatidylinositol anchors from parasitic protozoa and bacterial lipopolysaccharide.

In the present study, we evaluated the ability of GPI-anchored mucin-like glycoproteins purified from Trypanosoma cruzi trypomastigotes (tGPI-mucin) to trigger phosphorylation of different mitogen-activated protein kinases (MAPKs) and related transcription factors in inflammatory macrophages. Kinetic experiments show that the peak of extracellular signal-related kinase (ERK)-1/ERK-2, stress-activated protein kinase (SAPK) kinase-1/mitogen-activated protein kinase (MAPK) kinase-4, and p38/SAPK-2, phosphorylation occurs between 15 and 30 min after macrophage stimulation with tGPI-mucin or GPI anchors highly purified from tGPI-mucins (tGPI). The use of the specific inhibitors of ERK-1/ERK-2 (PD 98059) and p38/SAPK-2 (SB 203580) phosphorylation also indicates the role of MAPKs, with possible involvement of cAMP response element binding protein, in triggering TNF-alpha and IL-12 synthesis by IFN-gamma-primed-macrophages exposed to tGPI or tGPI-mucin. In addition, tGPI-mucin and tGPI were able to induce phosphorylation of I kappa B, and the use of SN50 peptide, an inhibitor of NF-kappa B translocation, resulted in 70% of TNF-alpha synthesis by macrophages exposed to tGPI-mucin. Finally, the similarity of patterns of MAPK and I kappa B phosphorylation, the concentration of drugs required to inhibit cytokine synthesis, as well as cross-tolerization exhibited by macrophages exposed to tGPI, tGPI-mucin, or bacterial LPS, suggest that receptors with the same functional properties are triggered by these different microbial glycoconjugates.

Serum levels of insulin-like growth factor binding proteins in Ecuadorean children with growth hormone insensitivity.

Although insulin-like growth factor binding proteins (IGFBPs) are known to be important modulators of the action of insulin-like growth factors (IGFs), regulation of their production in vivo is not completely understood. Serum concentrations of IGFBP-3, -4 and -5 and acid-labile subunit (ALS) were therefore examined in 20 children with growth hormone (GH) insensitivity before and after 6 months of therapy with recombinant human IGF-I (80 or 120 micrograms/kg twice daily). The IGFBP concentrations in these children were compared with those in 62 GH-deficient children receiving GH therapy for 3 months. Serum levels of IGFBP-3, -4 and -5 and ALS all increased significantly (p < 0.0001) in GH-deficient children in response to GH therapy, whereas no significant increases occurred in the children with GH insensitivity. These findings indicate that GH is responsible for the regulation of serum levels of IGFBP-3, -4 and -5 and ALS, and that IGF-I does not directly regulate the concentrations of these circulating IGFBPs.

The "two bag system" for variable intravenous dextrose and fluid administration: benefits in diabetic ketoacidosis management.

1 case-controlled retrospective analysis compared the "two bag system," based on the euglycemic clamp technique, versus the traditional "one bag" method for intravenous diabetic ketoacidosis management. The two bag system can provide more cost-effective intravenous dextrose and fluid delivery and enhance quality of care by improving the efficiency, timeliness, and flexibility of overall control.

Insulin-like growth factor binding protein-1 levels in the diagnosis of hypoglycemia caused by hyperinsulinism.

The diagnosis of hypoglycemia caused by hyperinsulinism may be difficult because insulin levels are not uniformly elevated at the time of hypoglycemia. Insulin-like growth factor binding protein-1 (IGFBP-1) is a 28 kd protein whose secretion is acutely inhibited by insulin. We hypothesized that serum levels of IGFBP-1 would be a useful marker of hyperinsulinism. We measured IGFBP-1 levels during the course of standardized fasting studies in hospitalized children; 36 patients became hypoglycemic during the fasting studies, and samples obtained at the point of hypoglycemia were analyzed. On the basis of the currently used diagnostic criteria, 13 children had hyperinsulinism, 16 had ketotic hypoglycemia or no disorder, 3 had hypopituitarism or isolated growth hormone deficiency, 2 had glycogen storage disease type 1 and 2 had fatty acid oxidation disorders. In control subjects (children with ketotic hypoglycemia or no disorder), IGFBP-1 levels rose during fasting to a mean of 343.8 +/- 71.3 ng/ml in the sample drawn at the time of hypoglycemia. Mean IGFBP-1 levels at hypoglycemia for the entire group with hyperinsulinism were 52.4 +/- 11.5 ng/ml, significantly different from levels seen in control subjects (p < 0.0001). In children with moderately controlled hyperinsulinism (fasting tolerance > 4 hours), mean IGFBP-1 levels at the time of hypoglycemia were 71.5 +/- 16.9 ng/ml. IGFBP-1 levels in the children with poorly controlled hyperinsulinism (fasting tolerance < 4 hours) failed to rise during fasting, with a mean of 30.1 +/- 10.4 ng/ml in the final sample. IGFBP-1 levels were inversely correlated with serum insulin and C-peptide levels (r = -0.71 and -0.72, respectively; p < 0.0001). Patients with other endocrinologic or metabolic diseases that result in fasting hypoglycemia demonstrated a rise in IGFBP-1 levels similar to that seen in ketotic hypoglycemia. Low serum levels of IGFBP-1 at the time of hypoglycemia provide an additional marker of insulin action that might help to differentiate hyperinsulinism from other hypoglycemic disorders.

Drug use and delinquency: shared and unshared risk factors in African American and Puerto Rican adolescents.

The shared and unshared psychosocial risk factors related to stage of drug use and delinquency were examined. The sample consisted of 655 African American and 600 Puerto Rican male and female adolescents. Net regression analysis was used to analyze the data. The results showed that adolescent stage of drug use and delinquency reflect shared and unshared risk factors. The magnitude of the risk factors for adolescent delinquency was greater than for stage of drug use. The findings support a socialization hypothesis (from parent, to personality, to behavior), and the data were congruent with a dispositional model (from child, to parent or peer, to behavior).

Non-islet-cell tumor associated with hypoglycemia in a child: successful long-term therapy with growth hormone.

Hypoglycemia occurred in a 2-year-old girl with neuroblastoma. Initially, growth hormone secretion was suppressed, and she had low levels of insulin-like growth factor (IGF)-I and IGF binding protein-3, but elevated levels of large molecular weight IGF-II. We postulated that the pathogenesis of her hypoglycemia involved production of IGF-II by her neuroblastoma, leading to GH suppression and an abnormally elevated ratio of IGF to IGF binding protein. She was successfully treated with growth hormone; treatment was associated with normalization of the growth hormone-dependent growth factor levels and with euglycemia.

Isolation and properties of a multicatalytic proteinase complex from Xenopus laevis skin secretion.

A multicatalytic proteinase complex present in the skin secretion of Xenopus laevis was purified and its enzymatic activity towards natural and synthetic peptides was investigated. We identified three activities: i) a C-terminal deamidation enzyme activity which exhibited selectivity for the Asp-Phe-NH2 and Phe-Leu-NH2 motifs of cerulein, minigastrin Leu-enkephalinamide, (des-Tyr1)Leu-enkephalinamide and diaminobenzylthiocyanate-DVDERDVRGFASFLNH2 (DABTC-DR8kermit); ii) an endopeptidase activity that cleaves peptide bonds on the carboxyl side of hydrophobic amino acid residues such as Tyr-Gly of LHRH, Ile-Ala of PGLa and Leu-Ala of buccalin; iii) an enzyme activity that cleaves peptide bonds at the dibasic sites of peptides of the dynorphin family. The molecular weight determined by Sephacryl S-400 molecular sieve filtration indicated an M(r) about 600 kDa. The activities characterized here exhibit an optimal pH of about 7.4. The activities of the multicatalytic complex were differentially inhibited by the classical inhibitors of proteases.

Isolation and properties of a multicatalytic proteinase complex from Xenopus laevis skin secretion

A multicatalytic proteinase complex present in the skin secretion of Xenopus laevis was purified and its enzymatic activity towards natural and synthetic peptides was investigated. We identified three activities: i) a C-terminal deamidation enzyme activity which exhibited selectivity for the Asp-Phe-NH2 and Phe-Leu-NH2 motifs of cerulein, minigastrin Leu-enkephalinamide, (des-Tyr1)Leu-enkephalinamide and diaminobenzylthiocyanate-DVDERDVRGFASFL NH2 (DABTCDR8kermit); ii) an endopeptidase activity that cleaves peptide bonds on the carboxyl side of hydrophobic amino acid residues such as Tyr-Gly of LHRH, Ile-Ala of PGLa and Leu-Ala of buccalin; iii) an enzyme activity that cleaves peptide bonds at the dibasic sites of peptides of the dynorphin family. The molecular weight determined by Sephacryl S-400 molecular sieve filtration indicated an Mr about 600 kDa. The activities characterized here exhibit and optimal pH of about 7.4. The activities of the multicatalytic complex were differentially inhibited by the classical inhibitors of proteases

Human neuroblastoma cells express a novel metallo-endopeptidase activity able to inactivate atrial natriuretic factor: inhibition during retinoic acid-induced differentiation.

A new metallo-endopeptidase which hydrolyzes atrium natriuretic factor (ANF) has been isolated from human neuroblastoma NB-OK-1 cells. In the present study we show that this metallo-endopeptidase is also present in several other human neuroblastoma cell lines, which include CHP 100, SH-SY5Y, SK-N-BE(2), BE(2)-C and BE(2)M-17. Additionally, we show that this endopeptidase activity is reduced to about 20% of the control during retinoic acid (RA)-induced neuronal differentiation in the RA-sensitive SK-N-BE(2) cells, but not in the RA-resistant BE(2)-M17 cells. This suggests that the inhibition is related to neuronal differentiation and not to a direct effect of 5 microM RA on the enzyme activity. This new enzyme is clearly distinct from neutral endopeptidase (NEP, EC 3.4.24.11) and angiotensin-converting enzyme (ACE,EC 3.4.15.1), since specific inhibitors for these endopeptidases (10 microM phosphoramidon and 1 mM captopril, respectively) had no effect on their activity. However, this enzyme was inhibited 100% by 10 mM o-phenanthroline showing an inhibitory spectrum similar to that of another novel metallo-endopeptidase recently isolated in our laboratory from Xenopus laevis skin secretion. Although the physiological function of this new enzyme in human neuroblastoma cells is not known at the present time, we suggest that it may participate in inactivation of neuropeptides such as atrium natriuretic factor (ANF), substance P, somatostatin-14 and bradykinin in vivo.

Human neuroblastoma cells express a novel metallo-endopeptidase activity able to inactivate atrial natriuretic factor: inhibition during retinoic acid-induced differentiation

A new metallo-endopeptidase which hydrolyzes atrium natriuretic factor (ANF) has been isolated from human neuroblastoma NB-OK-1 cells. In the present study we show that this metallo-endopeptidase is also present in several other human neuroblastoma cell lines, which include CHP 100, SH-SY5Y, SK-N-BE(2), BE(2)-C and BE(2)M-17. Additionally, we show that this endopeptidase activity is reduced to about 20 per cent of the control during retinoic acid (RA)-induced neuronal differentiation in the RA-sensitive SK-N-BE(2) cells, but not in the RA-resistant BE(2)-M17 cells. This suggests that the inhibition is related to neuronal differentiation and not to a direct effect of 5 microM RA on the enzyme activity. This new enzyme is clearly distinct from neutral endopeptidase (NEP, EC 3.4.24.11) and angiotensin-converting enzyme (ACE,EC 3.4.15.1), since specific inhibitors for these endopeptidases (10 microM phosphoramidon and 1 mM captopril, respectively) had no effect on their activity. However, this enzyme was inhibited 100 per cent by 10 mM o-phenanthroline showing an inhibitory spectrum similar to that of another novel metallo-endopeptidase recently isolated in our laboratory from Xenopus laevis skin secretion. Although the physiological function of this new enzyme in human neuroblastoma cells is not known at the present time, we suggest that it may participate in inactivation of neuropeptides such as atrium natriuretic factor (ANF), substance P, somatostatin-14 and bradykinin in vivo

Vesicular transport of myelin proteolipid and cerebroside sulfates to the myelin membrane.

The possibility that cerebroside sulfates and myelin proteolipid (PLP) could be simultaneously located in transport vesicles destined to be assembled in myelin was investigated in the brain of 20 day old rats. The brain was homogenized and fractionated according to Burkart et al. (J Biol Chem 257:3151-3156, 1982) to obtain a microsomal fraction that was further subfractionated in a linear sucrose density gradient following the procedure of Siegrist et al. (J Neurochem 33:497-504, 1979) to obtain a vesicular fraction which has been shown to transport cerebroside sulfates (Burkart et al., as above). This fraction was associated with acid hydrolase activity and had a lipid composition different from that of myelin and microsomal fractions. Studied by slab gel electrophoresis, dot blot, and Western blot analysis, using a highly specific anti-PLP antibody, it was found to contain myelin PLP. In view of previous findings of several laboratories including our own, the presence of myelin proteolipid in a vesicular fraction which is related to the transport of cerebroside sulfates gives further support to the hypothesis that the delivery of both constituents to the myelin membrane could be associated.

Hormonal and metabolic effects and pharmacokinetics of recombinant insulin-like growth factor-I in growth hormone receptor deficiency/Laron syndrome.

Profound growth failure despite elevated GH levels in GH receptor deficiency (GHRD) results from reduced insulin-like growth factor-I (IGF-I) synthesis. Recent reports of improved growth velocity in children with GHRD during IGF-I therapy indicate growth-promoting potential in humans. We evaluated the pharmacokinetics and metabolic/hormonal effects of recombinant human IGF-I (40 micrograms/kg every 12 h) given sc for 7 days to six adults with GHRD. Hypoglycemia (< 2.5 mmol/L) did not occur, and mean 2 h postprandial insulin levels were reduced. Urinary calcium increased 2-fold (P < 0.01), and serum calcium was unchanged. The mean integrated 24-h GH level was suppressed (6.5 +/- 2.1 to 1 +/- 0.2 micrograms/L), as were the number of peaks, area under the curve, and clonidine-stimulated GH release (all P < 0.05). The mean pretreatment IGF-I level (36 +/- 2 micrograms/L) was 19% of the Ecuadorian control value (190 +/- 15 micrograms/L), it achieved a peak (253 +/- 11 micrograms/L) between 2-6 h after IGF-I injection, and at 12 h it was 137 +/- 8 micrograms/L. There were no significant changes in the half-life (8.2 +/- 1.5 to 9.7 +/- 1.9 h) or metabolic clearance (0.35 +/- 0.1 to 0.24 +/- 0.05 mL/kg.min) between days 1 and 7; however, distribution volume increased (183 +/- 10 to 266 +/- 36 mL/kg; P < 0.03). Baseline IGF-II levels were 47% of the control value and decreased during IGF-I therapy (273 +/- 10 to 178 +/- 9 micrograms/L; P < 0.01), correlating inversely with IGF-I levels (r = -0.3; P < 0.001). Although IGF-binding protein-3 (IGFBP-3) levels were not significantly influenced, baseline IGFBP-2 levels (153% of the control) increased 45% (P < 0.01). We conclude that IGF-I (40 micrograms/kg every 12 h) given sc to adults with GHRD is safe; achieves normal levels of IGF-I; reduces insulin, IGF-II, and GH levels; and increases IGFBP-2 concentrations and urinary excretion of calcium.

Two-year results of treatment with depot leuprolide acetate for central precocious puberty.

We report results from 2 years of therapy with the long-acting form of the gonadotropin-releasing hormone (GnRH) analog leuprolide acetate, which was previously reported in short-term trials to be efficacious in the treatment of central precocious puberty. Thirteen girls and two boys, aged 1.9 to 9.7 years, who satisfied clinical criteria including GnRH-stimulated luteinizing hormone (LH) greater than 10 IU/L (mean radioimmunoassay LH, 29.1 +/- 5.54 IU/L), received depot leuprolide, 6 to 15 mg intramuscularly every 4 weeks. Estradiol (or testosterone), insulin-like growth factor I, and GnRH-stimulated gonadotropins were obtained at baseline, at 2 months, and at 6-month intervals with bone age determinations. Pubertal progression ceased in all patients, and menses did not occur. Mean increase in height during therapy was 5.77 +/- 2.0 cm/yr. Predicted adult height increased over baseline by 5.52 +/- 1.16 cm at 18 months. Mean estradiol values in the girls declined from 3.3 +/- 0.6 to 0.60 +/- 0.03 ng/dl, with no overlap of baseline and treatment values. The mean basal LH value was unchanged by therapy; mean basal and peak LH values for all follow-up GnRH stimulation tests were 4.05 +/- 0.57 and 4.95 +/- 0.70 IU/L, respectively. Basal and peak follicle-stimulating hormone (FSH) values were suppressed from 4.10 +/- 0.62 and 10.06 +/- 1.34 IU/L, respectively, to generally undetectable levels (< 1). Comparison with untreated control patients suggested that basal LH did not completely return to prepubertal levels, whereas FSH levels were suppressed below prepubertal levels. Estradiol, FSH, and LH levels reached their nadir by 2 months; in contrast, mean serum levels of insulin-like growth factor I progressively declined from +0.57 +/- 0.19 SD score to -0.06 +/- 0.22 SD score at 24 months. Two girls were withdrawn from the study because of reactions at injection sites, with apparent sterile abscess formation in one patient. This study provides evidence that (1) long-term treatment with depot leuprolide is characterized by immediate and sustained laboratory and clinical suppression, (2) GnRH-stimulated LH and random FSH and estradiol concentrations are useful laboratory measures of efficacy, and (3) the progressive increase in predicted adult height is temporally associated with decreased serum levels of insulin-like growth factor I and striking deceleration of bone age advancement.

Regulation of serum insulin-like growth factors and their binding proteins in Ecuadorean patients with growth hormone receptor dysfunction (growth hormone insensitivity).

Regulation of serum insulin-like growth factors (IGFs), IGF binding proteins (IGFBPs), and growth hormone (GH) binding protein (GHBP) has been investigated in Ecuadorean patients with GH receptor dysfunction (GHRD) and in their heterozygous relatives (parents). Serum IGF-I and IGF-II levels were measured by radioimmunoassay (RIA). IGFBPs were identified by Western ligand blotting of serum samples, following separation by sodium dodecyl sulphate polyacrylamide gel electrophoresis, and relative quantification was performed with a scanning laser densitometer. Serum GHBP levels were measured with a ligand-mediated immunofunctional assay (LIFA) using a monoclonal antibody raised against the GHBP. These values were then compared with values obtained from normal, sex-matched Ecuadorean controls. Serum IGF-I, IGF-II, IGFBP-3 and GHBP concentrations were markedly reduced and serum IGFBP-2 values increased in the patients with GHRD. Serum IGF-I and IGF-II values were positively correlated in the patients with GHRD, but were not related to the age of the patient. IGFBP-2 and IGFBP-3 concentrations were inversely correlated in the patients with GHRD. When analysed by age, however, IGFBP-2 was related inversely and IGFBP-3 related positively to the age of the patient. The serum IGF-II levels of the male heterozygotes were significantly reduced when compared with sex-matched controls, but considerable overlap with normal values was found. No other biochemical indices were significantly altered in either male or female heterozygotes. Thus, although GHRD is characterized by dramatic reductions in serum levels of GHBP, IGF-I, IGF-II and IGFBP-3, none of these assays provides a reliable biochemical marker for heterozygosity.

Pulsatile luteinizing hormone secretion in women with polycystic ovary syndrome under clomiphene citrate. Differences between responders and nonresponders.

Although administration of Clomiphene Citrate (CC) is an effective therapy for ovulation induction in PCO patients, 15 to 20% of PCO patients do not ovulate following CC treatment. The aim of this study was to compare the endocrine dynamics (LH pulsatile pattern, FSH and steroid hormone changes) in 6 patients who ovulated (PCOS) and 6 PCO patients who did not ovulate in response to CC (PCOR). Blood was collected at 15 min intervals for 4 hr on day 9 of the first menstrual cycle (control cycle) and on day 9 of the following (treatment) cycle. In this cycle all women received 100 mg CC/day from day 5 to day 9. LH was determined in all samples whereas FSH and estradiol were measured every 60 min. No significant differences were observed regarding the age, body mass index, degree of hirsutism, ovarian volumes and basal levels of reproductive hormones between both groups of PCO women. During the control cycle, the LH pulse amplitude and transverse LH mean concentrations in PCOR patients were higher than in PCOR patients whereas the LH pulse frequency was similar in both groups. No difference was found in FSH and estradiol values between both groups. Compared to the control cycle, PCOR patients showed no change in the pulse amplitudes and no difference in LH, FSH and estradiol values following CC treatment. In contrast, during the CC therapy in PCOS patients an increase in the LH amplitude (p less than 0.05), the transverse mean LH concentration (p less than 0.05), FSH and estradiol was observed.(ABSTRACT TRUNCATED AT 250 WORDS)