Study of the role of novel RF-amide neuropeptides in affecting growth hormone secretion in a representative non-human primate (Macaca mulatta).

RF amide peptide family with distinctive terminal -Arg-Phe-NH(2) signature is evolutionarily conserved from invertebrates to mammals. These neuropeptides have been shown to affect diverse functions in invertebrates and vertebrates including influencing pituitary hormone secretion. More recently, two members of this family 26-amino acid and 43-amino acid RF amide peptide (26RFa and 43RFa, respectively) originally isolated from frog have been cloned in rats and humans. Actions of these peptides on hormone secretion have not been studied in primates. In the present study, effect of iv administration of three different doses of human 26RFa and 43RFa on GH secretion was studied in a representative higher primate, the rhesus monkey. As control against these two peptides, normal saline and a scrambled sequence of 26RFa was administered. A set of four intact adult male monkeys received the administration in a random order. Peripheral blood samples were obtained from the chairrestrained but fully conscious animals for a period of 30 min before and 240 min after the administration at 15-min intervals. For quantitative measurement of GH concentration, a human GH chemiluminescent immunometric assay was used. Peripheral administration of 38 and 76 nmol doses of 26RFa significantly (P < 0.05) stimulated GH AUC during a 0-120 min period after injection of 26RFa. In contrast to 26RFa, administration of 43RFa appeared to suppress GH levels during the later stages of the sampling i.e. from 120 to 240 min period. Mean AUC during the period was significantly (P < 0.05) reduced by 76 nmol dose of 43RFa, while 38 nmol dose of 43RFa also had similar effect but lacked full statistical significance (P = 0.058). To our knowledge present study reports for the first time-specific stimulatory effect of 26RFa on the GH secretion and a novel inhibitory and delayed effect of 43RFa on the GH secretion in higher primates. In conclusion, present findings extend evidence for endocrine actions of RF amides in primates and suggest differential effect of these peptides on GH secretion in primates.

A single (99m)Tc-MIBI study to predict response to neoadjuvant treatment in sarcoma patiens.

Technetium-99m methoxy isobutyl isonitrile ((99m)Tc-MIBI) was used as a tumour imaging agent to predict the response of neoadjuvant treatment in patients with bone and soft tissue sarcoma. Our study included 31 patients (M:F = 23:8), 17 having osteosarcomas and 14 with soft-tissues sarcomas. Scintigraphy with (99m)Tc-MIBI was performed before the initiation of the neoadjuvant treatment. Static images were acquired at 10 and 60min post-injection and lesion to normal (L/N) ratios and washout rates (WR%) were calculated. Tumour response was assessed by detecting percent necrosis in a surgically resected specimen. Responses were correlated and compared with WR%. Percentage of tumour necrosis was 71.35±20.20% (mean±SD) with eight good and 23 poor responses. On visual analysis, 16 showed homogeneous, 11 heterogeneous and 4 doughnut shaped pattern of uptake. Seventy five percent of good responders had homogeneous uptake. Early and delayed L/N ratios were significantly different in both good and poor responders (P=0.006 and P<0.001, respectively) but correlated poorly with the tumour necrosis values in the specimen (R=0.23 and 0.06 respectively). Mean washout rate was 26.13±11.25% (median = 29%) and there was weak correlation between tumour necrosis and WR% (r=-0.32, P=0.029). The mean WR% of good responders was 15.0±10.0% and that of poor responders was significantly higher (30.1±8.8%, P=0.003). Good responders by 88% were below the median cut-of value. In conclusion WR% of (99m)Tc-MIBI may be used before surgery to identify poor responders to neoadjuvant treatment in patients with bone and soft tissue sarcomas.

Response rate of Pakistani children with acute lymphoblastic leukaemia to Medical Research Council acute lymphoblastic leukaemia 97 chemotherapy protocol.

BACKGROUND: Acute lymphoblastic leukaemia (ALL), a malignancy of lymphoid lineage cells, has excellent prognosis in children. In Pakistan, a few studies highlighted the response of ALL to chemotherapy. The Present study was planned to see the response rate of Pakistani children with ALL to Medical Research Council ALL 97 (MRCALL97) chemotherapy protocol. This descriptive case series was conducted at the Department of Haematology, Armed Forces Institute of Pathology and the Department of Paediatric Oncology, Combined Military Hospital, Rawalpindi from 16th of February 2007 to 16th of August 2007. METHODS: Diagnosed children with ALL fulfilling the inclusion criteria were interviewed regarding history of the present, past illnesses, and family history. Physical examination was performed. Presenting clinical features, blood counts and blood and bone marrow blasts percentage were used to see the response on day 29 post chemotherapy. The data was recorded on a structured proforma for statistical analysis. RESULTS: A total of 33 patients were studied including 26 males and 7 females. Twenty-five patients belonged to age group 2-9 years, and 8 to < 2 or > 9 years, median age being 4.5 years. Presenting WBC count was < 50 x 10(9)/L in 30 patients and > 50 x 10(9)/L in 3 patients. At the end of induction, complete remission was achieved in 31 out of 33 (94%) patients while two patients did not achieve remission. CONCLUSION: Response rate of Pakistani children with ALL to chemotherapy was superior to the previously reported figures from Pakistan.

CD5-positive acute lymphoblastic leukemia.

CD5-positive B-ALL is a rare variant of Acute Lymphoblastic Leukemia (ALL). In literature, only three cases have been reported so far. This fourth case report describes a young lady who was diagnosed as ALL (L-2) on bone marrow examination and was found to be CD5 positive B-cell acute lymphoblastic leukemia on immunophenotyping. Cytogenetic analysis revealed translocation t(9:22).