Feeding behavior during long-term hexarelin administration in young and old rats.

Ghrelin, a 28-amino-acid peptide isolated from the stomach, is the natural ligand of the GH-secretagogues receptor-1a (GHS-R1a) and, so far, the only discovered circulating appetite-stimulating hormone. Similarly to ghrelin, many synthetic compounds belonging to the GHS family stimulate both GH secretion and feeding, whereas some stimulate GH secretion only. In the past years, studies have focused on the potential of the GHS to stimulate GH release during long-term treatment in humans and experimental animals. Few data are available about the extraendocrine effects of the GHS during several weeks of treatment, particularly in old rats. The aim of the present study was first to identify the lowest dose of hexarelin giving maximal stimulation of food intake both in young (3-month-old) and old rats (24-month-old). A dose-response study (80-320 microg/kg, s.c.) revealed that hexarelin at the dose of 80 microg/kg gave reproducibly maximal stimulation of food consumption in young as well as in old rats. Second, we evaluated the effect of 8-week daily sc treatment with hexarelin in young and old male rats. The outcome of the chronic study was that hexarelin (80 microg/kg, s.c., once daily) maintained a persistent significant orexigenic action throughout the treatment period, both in young and old rats. Interestingly, hexarelin treatment did not affect body weight gain either in young or old rats. We conclude that hexarelin is endowed with long-lasting orexigenic activity and might represent a potential therapeutic approach for pathological conditions characterized by a decline in food intake.

Fludarabine and cladribine in relapsed/refractory low-grade non-Hodgkin's lymphoma: a phase II randomized study.

BACKGROUND: It is unclear whether the purine analogs fludarabine (Flu) and cladribine (CdA) are non-resistant. PATIENTS AND METHODS: Sixty patients with relapsed or refractory low-grade NHL were randomly allocated to initial treatment with either Flu 25 mg/m2, or CdA 0.14 mg/kg, each for five consecutive days every four weeks. Upon treatment failure, eligible patients were crossed over to the other study drug. RESULTS: Overall response and CR were 68% and 48% with Flu, and 72% and 38% with CdA, respectively. For responders, actuarial three-year progression-free survival was 58% with Flu and 52% with CdA. Treatment with both drugs was well tolerated, with toxic effects primarily hematological. Two patients (8%) in the Flu group and 15 patients (47%, P = 0.001) in the CdA group were taken off study because of persistent hematological toxicity. After cross over, none of seven refractory patients responded, while eight of nine previously responsive patients achieved second responses. CONCLUSIONS: Our study confirms that Flu and CdA have similar response rates and durations. However, further studies are required to optimize the CdA schedule and dosage in order to ameliorate its toxic profile while maintaining antitumor activity. The two drugs appear to be cross-resistant.

Teaching residents about development and behavior: meeting the new challenge.

OBJECTIVE: To determine the teaching methods, materials currently used, and unmet needs for teaching developmental-behavioral pediatrics (DBP) at pediatric training programs in the United States. DESIGN: Cross-sectional survey of US pediatric residency training programs. The survey questionnaire consisted of 3 instruments: a program director survey, a developmental-behavioral pediatrics survey, and an adolescent medicine survey. PARTICIPANTS: Survey packets were mailed in January 1997 to 211 programs identified by mailing labels from the Association of Pediatric Program Directors. RESULTS: Data from 148 programs (70%) completing both the DBP survey and program director survey were analyzed. Ninety-five percent of programs reported a block rotation, and 95% of those stated that the rotation was mandatory. Eighty-seven percent had a formal curriculum. Most programs reported using articles, lecture outlines, and precepting for teaching DBP. Few programs used standardized case-based or computerized materials. Most programs, however, indicated a desire for these materials. Few programs felt that 4 topics were covered adequately: adoption (12%), violence (24%), substance use (28%), and conduct problems (41%). Programs that perceived that they covered these topics adequately were more likely to use written cases as part of their curriculum (Mann-Whitney test, 1373.5; P=.04). Barriers to teaching included lack of adequate faculty, time, money, and curricular resources. CONCLUSIONS: Pediatric residency programs have made significant gains in mandatory DBP training. However, many programs report a lack of adequate faculty, teaching materials, and methods. Responding programs indicated an interest in case-based materials. This approach may represent an alternative and underutilized resource for teaching DBP.

Novel hexarelin analogs stimulate feeding in the rat through a mechanism not involving growth hormone release.

Growth hormone-releasing peptides (GHRPs) are a class of small peptides that stimulate growth hormone (GH) release in several animal species, including the human. Moreover, GHRPs injected into the brain ventricles stimulate feeding in the rat. The aim of this study was to evaluate the GH-releasing properties of a series of novel GHRP analogs and the possible existence of functional correlations between the GH-releasing activity and the effects on feeding behavior. Two well-known hexapeptides, GHRP-6 and hexarelin, given s.c., dose dependently stimulated both GH release and feeding behavior in satiated rats. However, in a series of tri-, penta- and hexapeptide analogs of hexarelin, some compounds were active either on GH release or on eating behavior. Interestingly, even minor structural modifications resulted in major changes of the pharmacological profile. We conclude that GHRPs have orexigenic properties after systemic administration which are largely independent from the effects they exert on GH release.

Adolescent medicine training in pediatric residency programs: are we doing a good job?

OBJECTIVES: To determine how pediatric residency programs are responding to the new challenges of teaching adolescent medicine (AM) to residents by assessing whether manpower is adequate for training, whether AM curricula and skills are adequately covered by training programs, what types of teaching methodologies are used to train residents in AM, and the needs for new curricular materials to teach AM. DESIGN: A 3-part 92-item survey mailed to all US pediatric residency training programs. SETTING: Pediatric residency programs. PARTICIPANTS: Residency program directors and directors of AM training. MAIN OUTCOME MEASURES: AM divisional structure, clinical sites of training, presence of a block rotation, and faculty of pediatric training programs; training materials used and desired in AM; perceived adequacy of coverage of various AM topics; competency of residents in performing pelvic examinations in sexually active teens; and manpower needs. RESULTS: A total of 155/211 (73.5%) of programs completed the program director and the AM parts of the survey. Ninety-six percent of programs (size range, 5-120 residents) had an AM block rotation and 90% required the AM block; those without a block rotation were more likely to be larger programs. Only 39% of programs felt that the number of AM faculty was adequate for teaching residents. Almost half of the programs reported lack of time, faculty, and curricula to teach content in substance abuse. Besides physicians, AM teachers included nurse practitioners (28%), psychologists (25%), and social workers (19%). Topics most often cited as adequately covered included sexually transmitted diseases (81.9%), confidentiality (79.4%), puberty (77.0%), contraception (76.1%), and menstrual problems (73.5%). Topics least often cited as adequately covered included psychological testing (16.1%), violence in relationships (20.0%), violence and weapon-carrying (29.7%), and sports medicine (29.7%). Fifty-eight percent of 137 respondents thought that all or nearly all of their residents were competent in performing pelvic examinations by the end of training; there was no difference between perceived competence and the residents' use of procedure books. Seventy-four percent used a specific curriculum for teaching AM; materials included chapters/articles (85%), lecture outlines (76.1%), slides (41.9%), videos (35.5%), written case studies (24.5%), computerized cases (6.5%), and CD-ROMs (3.2%). Fifty-two percent used Bright Futures, 48% used the Guidelines for Adolescent Preventive Services, and 14% used the Guide to Clinical Preventive Services for teaching clinical preventive services. Programs that used Bright Futures were more likely to feel that preventive services were adequately covered in their programs than those who did not (78% vs 57%). A majority of programs desired more learner-centered materials. CONCLUSIONS: Although almost all pediatric programs are now providing AM rotations, there is significant variability in adequacy of training across multiple topics important for resident education. Programs desire more learner-centered materials and more faculty to provide comprehensive resident education in AM.

Effect of long-term administration of Hexarelin on the somatotrophic axis in aged rats.

The growth hormone-releasing peptide Hexarelin (Hexa; 80 micrograms/kg-1, s.c.) was administered for 30 and 60 days to old rats. The GH-releasing effect of Hexa was maintained during chronic treatment. At the end of the treatment, old rats were administered once with Hexa which elicited a greater GH response in rats chronically treated with the peptide than in those receiving a placebo. Pituitary GHmRNA concentrations were significantly lower in the older rats than in the younger animals, irrespective of Hexa treatment, while the GH protein content was similar in all the groups studied. The same was true for hypothalamic GHRH, whose synthesis was reduced in all the older animals but not in the young, in the presence of maintained concentrations of the peptide. Somatostatin mRNA concentrations were significantly higher in the hypothalami of older rats and administration of Hexa for 30 or 60 days brought the concentrations of somatostatin mRNA of aged rats to 'young' levels. Treatments with Hexa failed to alter the circulating levels of IGF-1. The data reported in this article indicate that long-term treatment with Hexa normalized some biological indices of somatotrophic function in aged rats.

Effects of GH and IGF-I administration on GHRH and somatostatin mRNA levels: I. A study on ad libitum fed and starved adult male rats.

The individual role played by GH and IGF-I in the regulation of hypothalamic GHRH and SRIF gene expression is still object of debate. We have investigated the effect of exogenously administered recombinant hGH (rhGH) and recombinant hIGF-I (rhIGF-I) in ad libitum fed control and starved rats, the latter an animal model which is characterized by low circulating levels of endogenous GH and IGF-I. Adult male rats were fed ad libitum (C) or food-deprived (S) for 72 hours; rats in either C or S groups were treated with systemic administration of rhGH and rhIGF-I for 3 days. GHRH, SRIF and GH mRNA levels were evaluated by Northern and slot blot hybridization. Administration of rhGH (250 micrograms/kg/twice daily, sc) induced a significant inhibition of GHRH and a significant stimulation of SRIF mRNA levels in C rats; GH treatment was, however, ineffective on both neuropeptide mRNA levels in the S group. Continuous infusion of rhIGF-I (300 micrograms/kg/day, sc) induced a significant increase of SRIF levels in both C and S rats but did not modify GHRH mRNA levels in either group. In the pituitary, GH mRNA levels followed a pattern very similar to that of GHRH. These results provide evidence for a direct role of GH in the inhibition of GHRH mRNA levels; IGF-I appears more involved in the direct stimulation of SRIF mRNA levels.

Effects of GH and IGF-I administration on GHRH and somatostatin mRNA levels: II. A study in the infant rat.

It is generally accepted that growth hormone influences its own secretion by modulating the activity of GHRH and SRIF neurons. To investigate if GH feedback mechanisms are already operating in the early postnatal life of the rat, we have studied in 10-day-old pups the effects of rhGH and rhIGF-I administration on GHRH and somatostatin mRNA levels. The same experiment was also performed in pups passively immunized with an anti-GHRH antiserum from the day of birth. The latter animal model had been previously characterized for presenting reduced levels of circulating GH and IGF-I. In control pups, neither rhGH (250 micrograms/kg, b.i.d., sc) nor rhIGF-I (150 micrograms/kg, b.i.d., sc) administration induced significant changes of GHRH and SRIF gene expression. The passive immunization against GHRH induced per se a trend toward an increase and a reduction of GHRH and SRIF mRNA levels, respectively. Also in these rats the treatment for 3 days with rhGH and rhIGF-I did not further modify the GHRH and SRIF mRNA levels. Based on these results, we conclude that in the 10-day-old rat GH feedback mechanisms are poorly operative, though a direct ultra-short loop mechanism involving the GHRH and SRIF systems seems already operating.

Hexarelin stimulation of growth hormone release and mRNA levels in an infant and adult rat model of impaired GHRH function.

Hexarelin, a GH-releasing peptide, is an effective GH secretagogue in man and a variety of experimental animals. In the present study, we sought to characterize the effects of short-term Hexarelin treatment on GH release and GH mRNA levels in infant and young-adult rats and in rats of either age passively immunized with an antiserum against GHRH (GHRH-Ab). Hexarelin (80 micrograms/kg, b.i.d. s.c.), administered for 3, 5 or 10 days to 8-, 6- and 1-day-old rats, respectively, induced a progressive enhancement of the plasma GH rise elicited by a subsequent acute Hexarelin (80 micrograms/kg s.c) challenge when pups were 10 days old. As expected, GHRH-Ab treatment decreased GH concentrations in 10-day-old pups. In GHRH-Ab-treated pups, Hexarelin administration for 3-10 days significantly enhanced the GH response to the acute Hexarelin injection, though the mean plasma GH values remained significantly lower than in the respective control group. Hexarelin treatment did not alter GH mRNA levels in control pups. In GHRH-Ab-treated pups Hexarelin treatment for 3 and 5 days, but not 10 days, restored GH mRNA levels to control values. In young-adult male rats, regardless of antiserum treatment, Hexarelin administration for 5 or 10 days significantly suppressed the GH response to a subsequent acute challenge with the peptide. Yet, 5-10 days of Hexarelin treatment did not alter GH mRNA in control young-adult rats. In adult rats GHRH-Ab also decreased GH mRNA levels, but 10 days of Hexarelin treatment were necessary to return GH mRNA back to normal levels. These results indicate that: (1) the effects of Hexarelin on GH release and GH mRNA levels may be unrelated events; (2) deprivation of GHRH function discloses the ability of Hexarelin to stimulate GH mRNA levels; (3) age plays a crucial role in setting the pituitary responsiveness to short-term Hexarelin treatment, and (4) the different ability of Hexarelin to stimulate GH release and GH synthesis in neonatal and young-adult rats may have clinical relevance in the chronic administration of the peptide.

Acute hepatic toxicity during cyclic chemotherapy in non Hodgkin's lymphoma.

BACKGROUND AND OBJECTIVE: Hepatic toxicity directly related to the drugs administered in cyclic chemotherapy (CT), although sometimes serious, does not limit the treatment of non-Hodgkin's lymphoma (NHL). Nevertheless, reports of reactivation of viral hepatitis in NHL patients with B virus (HBV) infection are becoming more frequent. The recent observation of two cases of severe liver toxicity directly correlated to CT and a case of fatal hepatic failure due to HBV replication prompted us to evaluate the hepatic toxicity of CT in 98 consecutive B-cell NHL patients treated with relatively homogeneous cyclic CT. METHODS: Acute hepatic toxicity was retrospectively evaluated in 98 consecutive B-cell NHL patients who received induction CT. HBV and HCV markers were checked at presentation. All patients were tested for ALT and bilirubin before every CT course, while tests for HBV-DNA and/or for HCV-RNA were performed with PCR only when hepatitis occurred. RESULTS: At presentation 22 patients (22.4%) were positive for HBsAg, and 11 (15.9%) were positive for anti-HCV. Acute hepatitis developed in 12 (12.2%) NHL patients: 8 (out of 22) in HBsAg-positive and anti-HCV-negative patients, 3 (out of 76) in HBsAg-negative patients, and 1 (out of 11) in anti-HCV-positive patients. Hepatitis was attributed to reactivation of chronic B hepatitis in 3 patients and to drug toxicity in 3 others; hepatitis was undefined in 6 cases. INTERPRETATION AND CONCLUSIONS: Drug-related liver toxicity is not a rare occurrence in NHL patients. Reactivation of HBV replication is responsible for a relevant number of the hepatitis cases observed. We did not detect acute hepatitis due to the reactivation of HCV replication (in chronic C hepatitis carriers).

Role of the neuronal histaminergic system in the regulation of somatotropic function: comparison between the neonatal and the adult rat.

To study possible age-related differences in the role of neuronal histaminergic pathways in the control of GH secretion, the effects of alpha-fluoromethylhistidine (alpha-FMH), an irreversible inhibitor of histamine (HA) synthesis, were examined on basal and opioid-induced GH release in neonatal and adult rats. The mechanisms involved in such effects were evaluated by measuring pituitary GH mRNA levels and hypothalamic levels of GH-releasing hormone (GHRH) and somatostatin (SRIF) mRNAs. Daily injection of alpha-FMH (20 mg/kg, s.c.) in pups of either sex, from birth until 10 days of age, caused a significant increase in baseline plasma GH and potentiated the GH response to the [Met5]-enkephalin analog FK 33-824 (1 mg/kg, s.c.) administered 3 h after the last alpha-FMH injection. GH and SRIF mRNA levels were significantly higher in alpha-FMH-treated pups than in controls, whereas no difference was observed in GHRH mRNA levels. In young adult male rats, acute administration of alpha-FMH (100 mg/kg, s.c., 3 h before) did not change significantly basal GH levels but potentiated FK 33-824 (0.3 mg/kg, intracarotid)-induced stimulation of GH secretion. Repeated administration of alpha-FMH (200 micrograms/rat, i.c.v., for 3 days) failed to modify basal and FK 33-824-induced GH secretion, caused a significant reduction in hypothalamic GHRH mRNA levels and left SRIF and GH mRNAs unchanged. These findings indicate that HA exerts an inhibitory effect on GH secretion in both neonatal and adult rats. The different effects of short-term HA depletion on hypothalamic and pituitary indices of somatotropic function observed at the two age periods may be ascribed to the immaturity of the HA system in early postnatal life and to a different functional role of GH-regulatory factors during ontogeny.

Mechanism of action of Hexarelin. I. Growth hormone-releasing activity in the rat.

We have reported Hexarelin (HEXA), an analog of growth hormone-releasing peptide 6 (GHRP-6), potently stimulates growth hormone (GH) secretion in infant and adult rats. This study was undertaken to further investigate Hexarelin's mechanisms of action. In 10-day-old pups, treatments with HEXA (80 micrograms/kg, b.i.d.) for 3-10 days significantly enhanced, in a time-related fashion, the GH response to an acute HEXA challenge. Qualitatively similar effects were elicited in pups passively immunized against growth hormone-releasing hormone (GHRH) from birth. In adult male rats, a 5-day pretreatment with HEXA (150 micrograms/kg, b.i.d.) did not enhance the effect of the acute challenge, and the same pattern was present after a 5-day pretreatment in male rats with surgical ablation of the mediobasal hypothalamus (MBH-ablated rats). In addition, in adult sham-operated rats, Hexarelin (300 micrograms/kg, i.v.) induced a GH response greater (p < 0.05) than that induced by GHRH (2 micrograms/kg, i.v.). However, in MBH-ablated rats 7 days after surgery, GHRH was significantly (p < 0.05) more effective than HEXA, and 30 days after surgery HEXA and GHRH evoked similar rises of plasma GH. Finally, the in vitro Hexarelin (10(-6) mol/l) effect was transient while GHRH (10(-8) mol/l) induced a longer lasting and greater GH release. Three different mechanisms, not mutually exclusive, are postulated for Hexarelin stimulation of GH secretion in vivo: a direct action on the pituitary, though of minor relevance; an indirect action that involves release of GHRH, of relevance only in adult rats; and an action through the release of a still unknown hypothalamic "factor", which in infant and adult rats elicits GH release acting sinergistically with GHRH.

Diagnostic pitfalls of echography in a case of hepatic cavernous hemangioma.

An ecographic study of the liver in a 55-year-old female, with a history of mastectomy for a breast ductal cancer, showed multiple focal lesions. On computer tomography, we interpreted these lesions as metastatic disease. 99m Tc-labeled RBC showed non-homogeneous flow distribution in the right lobe of the liver. Fine needle aspiration biopsy under ecographic guidance showed no metastatic disease, and suggested a vascular lesion. The presence of spindle-shaped cells, reactive for CD 34 and for factor VIII, enabled definitive diagnosis of angiomatous lesion. Cytological confirmation of each hepatic mass is a mandatory prerequisite for any therapy.

Bone marrow biopsy for the staging of non-Hodgkin's lymphoma: bilateral or unilateral trephine biopsy?

AIM: The occurrence of unilateral involvement in bilateral bone marrow trephine biopsies in non-Hodgkin's lymphomas (NHL) at disease onset (10-20% of cases) has been reported since the early 70s. Therefore, although these studies were based on small series, the use of bilateral bone marrow biopsies has become the rule. However, the clinical value of this procedure has never been clearly established. The aim of the present study was to ascertain the true value of bilateral bone marrow biopsy in the staging of NHL. STUDY DESIGN: We examined 368 cases of NHL (A-H according to the Working Formulation) (WF), without leukemic involvement of the peripheral blood, in order to evaluate: 1) the incidence of unilateral bone marrow involvement; 2) the percentage of patients who, as a result of unilateral bone marrow involvement, changed from stages I-II to stage IV; 3) assessment of response to therapy for patients with both bilateral or unilateral bone marrow involvement. RESULTS: In the A-C NHL groups of WF there was a unilateral bone marrow involvement of 8.8%. Overall, bone marrow involvement induced a change from clinical stages I-II to stage IV in 5.6% of cases, a figure which would correspond to a false negative rate of 2.8%, if unilateral bone marrow biopsy was performed. In the D-F and G, H groups of WF, unilateral involvement was 10.1% and 8.5% respectively; the change in stage from I-II to IV by unilateral bone marrow involvement respectively amounted to 1.4% and 2.8%, which correspond to respective false negative rates of 0.7% and 1.4%. CONCLUSIONS: On the basis of these results and of the present therapeutic strategies, we propose: bilateral bone marrow biopsy for clinical stages I-II of all NHL; no bone marrow biopsy at disease onset for clinical stages III and IV of A to H histologic subtypes of the WF; unilateral bone marrow biopsy (A-C subtypes of the WF) or bilateral (D-H of the WF), after the regression of extramedullary localizations.

Small peptides as potent releasers of growth hormone.

Newly synthesized peptides are described which release growth hormone in the infant rat and their biological activity is compared with known GHRPs. Some of these peptides are the most potent GHRPs reported to date.

A cooperative study of epirubicin with cyclophosphamide, vincristine and prednisone (CEOP) in non-Hodgkin's lymphoma.

BACKGROUND: The purpose of our cooperative trial was to investigate whether epirubicin (EPI) at 90 mg/m2 in a CHOP-like combination (called CEOP) could increase complete response (CR) and survival rates in non-Hodgkin lymphoma (NHL) patients while maintaining a tolerable degree of toxicity. METHODS: Between September 1986 and July 1992, 218 patients from 12 Centers in Lombardy entered this study. The inclusion criteria were: a histological diagnosis of intermediate or diffuse large cell (DLC) NHL and no previous radio-chemotherapy. The patients in stages IA and IIA (both intermediate and DLC) received four CEOP courses followed by local/regional radiotherapy; those with intermediate NHL in stages IB, IIB, III A and B and IV A and B received six CEOP courses and, if they achieved CR, three further courses as consolidation. RESULTS: Among the 160 evaluable patients, CR was observed in 90% of the subjects with DLC-NHL (stages IA and IIA) and in 59% of those with intermediate-grade NHL (all clinical stages). If the clinical stages are considered separately, the CR rates were 92% for stages IA, IIA and 53% for stages IB, IIB, III A and B, IV A and B. Relapses occurred in 20% of the patients treated with four CEOP courses plus radiotherapy and in 31% of those who received nine CEOP courses because of the advanced stage of their disease. As of May 1994, the median follow-up was 42 months. If all of the patients are considered together, the 7-year overall survival (OS) probability was 64% and the 7-year disease-free survival (DFS) probability 67%. In comparison with stages III/IV, the patients in stages I-II had better DFS (7-year chance 77% vs 56%, p < 0.03). Hematological toxicity was acceptable, and a delay in the administration of CEOP chemotherapy was required in only three patients. No life-threatening infections were recorded. CONCLUSIONS: Our cooperative study of the use of the CEOP combination in NHL patients shows that response rates and the length of DFS are equal to the best results obtained with CHOP and more intensive programs, although further confirmation must be provided by means of a longer follow-up and a more careful analysis of prognostic factors according to the recently proposed international index. In our experience, an EPI dose of 90 mg/m2 has negligible toxicity (particularly on bone marrow), even in elderly patients. These findings are interesting since it is well known that myelotoxicity is the principal limiting factor for the majority of anthracycline-containing regimens used in the treatment of potentially curable NHL.

Undifferentiated granulocytic sarcoma: a case with epidural onset preceding acute promyelocytic leukemia.

This study reports a case of granulocytic sarcoma that developed in the epidural zone 25 days before clinical evidence of an acute promyelocytic leukemia. The case presented the diagnostic difficulties that are common to all aleukemic granulocytic sarcomas. Moreover, it highlights the very rare association between granulocytic sarcoma and acute promyelocytic leukemia, which is far from being explained.