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Biomedical subjects

R F Murphy

Publications and source records attributed to R F Murphy.

244 records · Page 14Linked to original sources
PubMedDate not supplied

Circulating immunoreactivities of gastrin, glucagon and VIP after jejuno-ileal bypass.

Seven Sprague-Dawley rats (404-440 g) underwent a 90% jejuno-ileal bypass (JIB); the functional loop consisted of 1/3 ileum and 2/3 jejunum with the bypassed loop being anastomosed to the ascending colon. Seven control rats were sham-operated. After 35 days, the rats were fasted 18 hours and venous blood was collected. Immunoreactivity of gastrin, measured with an antibody binding equally to G17 and G34, was higher in the plasma of the JIB (256 +/- 55 SEM pg/ml) than control (85 +/- 9 pg/ml) rats. This agrees with recent human studies but is in conflict with results in less mature rats. VIP levels were not significantly different. Glucagon-like immunoreactivity measured with antibodies specific for the C- and N-terminal regions of the hormone, respectively, were also higher in the JIB (510 +/- 40 and 129 +/- 15 pg/ml) rats.

Animals↗
PubMedDate not supplied

Neuropeptide K-(1-24)-peptide: storage and release by carcinoid tumors.

An antiserum directed against the COOH-terminal region of neuropeptide K-(1-24)-peptide that shows only 0.5% reactivity with neuropeptide K has been used in radioimmunoassay to study the posttranslation processing of human beta-preprotachykinin. A primary midgut carcinoid tumor contained high concentration of substance P (2970 pmol/g), neurokinin A (3660 pmol/g) and neuropeptide K-(1-24)-peptide (3430 pmol/g) but only a very low concentration (less than 5 pmol/g) of intact neuropeptide K. Neuropeptide K-(1-24)-peptide was also detected in extracts of metastatic tumor tissue from four patients with midgut carcinoid tumors. The amino acid sequence of tumor neuropeptide K-(1-24)-peptide was identical to that predicted from the nucleotide sequence of a human beta-preprotachykinin cDNA. The fasting plasma concentration of neuropeptide K-(1-24)-peptide was elevated in a patient with the carcinoid syndrome (821 fmol/ml compared with less than 18 fmol/ml in healthy subjects) and rose approximately 2-fold after intravenous pentagastrin. The study has demonstrated that the Lys25-Arg26 bond in neuropeptide K (corresponding to Lys96-Arg97 in the precursor) is an important processing site in human beta-preprotachykinin.

Aged↗
PubMedDate not supplied

Interaction of NPY and VIP in regulation of myometrial blood flow and mechanical activity.

The occurrence, molecular characteristics and biological function of neuropeptide Y (NPY) has been studied in the female genital tract of non-pregnant rabbits. NPY immunoreactivity was demonstrated throughout the genital tract. Maximum concentrations were found in the salpinx (fallopian tube), 570 pmol/g (median) lower within the uterine body (1.5 pmol/g), cervix (2.8 pmol/g) and vagina (3.6 pmol/g). In vitro, NPY had a dose-dependent stimulatory effect on non-vascular smooth muscle (ED50 10(-9) mol/l) as studied by myometrial tension recordings. In vivo, NPY (50 pmol/min.kg) induced a dose-related, non-adrenergic and non-cholinergic decrease in myometrial blood flow. Small C-terminal (NPY31-36) or N-terminal (NPY1-16) fragments of NPY had no effect on myometrial blood flow. NPY was found to interact with the smooth muscle effect of VIP; the presence of VIP (10(-8) mol/l) counteracted the contraction elicited by NPY (10(-8) mol/l) returning the response to control value. VIP and NPY displayed a similar physiological antagonism on myometrial blood flow. There was a clear difference in the response to VIP and NPY as the effect of NPY on myometrial blood flow first appeared after a lag period of 2 minutes whereas the effect of VIP was almost instantaneous. It is concluded that NPY and VIP may interact in the local nervous control of genital functions.

Animals↗
PubMedDate not supplied

Effects of some neurokinin A analogues on tachykinin-induced contraction of guinea pig trachea.

A series of analogues of neurokinin A (NKA) has been synthesized and characterized by testing for their abilities, in vitro, to contract guinea pig tracheal smooth muscle or to antagonize NKA-, NKB- and SP-induced contraction of this tissue. Substitution of NKA residues Gly8 or Leu9 by conformationally restricting amino acids produced peptides that were antagonists of NKA action, but the type and specificity of the antagonism depended on the size of the peptide. Thus, while [Ala5, Aib8, Leu10]NKA(2-10) showed no agonism and was a specific, competitive antagonist of NKA, [Ala5, Aib8, Leu10]NKA(4-10) was a noncompetitive antagonist of NKA and substance P (SP) and was itself a weak agonist at concentrations above 10(-7) M.

Amino Acid Sequence↗
PubMedDate not supplied

Venture profile analysis.

Imposed restrictions on inpatient revenue have encouraged hospitals to seek alternative sources of revenue through diversification. The venture profile analysis is a low-cost, orderly process to help hospitals plan for service diversification. Potential business ventures are assigned a weighted score based on nine evaluation criteria. Potential business ventures with high relative scores should be those opportunities with the greater prospects of success and those deserving of serious consideration by the hospital. The format of the profile facilitates active involvement of board members in the decision making process and prudent management of risk in market-based strategic planning.

Decision Making, Organizational↗
PubMedDate not supplied

Dental health of Louisiana residents based on the ten-state nutrition survey.

The dental health status of 4,006 residents of Louisiana was analyzed, based on data in the 1968-70 Ten-State Nutrition Survey funded by the U.S. Government. These data were based on examinations of census districts in which the average per capita income was in the lowest quartile for the nation. A considerable variation in the prevalence of dental diseases was found among the Louisiana residents according to age. The females examined had a slightly higher DMF (decayed, missing, and filled permanent teeth) score, a lower OHI (oral hygiene index) score, and a slightly lower PI (periodontal index) score than did the males. The dental caries attack rate did not vary much by race, but the whites examined had received a much greater amount of dental care than had their black counterparts. The OHI scores of the blacks were higher than those for the whites in both the debris and calculus components. The PI scores were higher for the blacks than for the whites. More white persons than blacks were edentulous; this result, however, tends to confirm the observation of increased dental care in white persons. The percentages of persons with periodontal disease and periodontal pockets were considerably higher among persons with incomes below the poverty level, and a greater percentage of blacks had incomes below that level. The data thus apparently indicate that the major determinants of dental health status in Lousiana are age and level of income; race appears to be the major determinant of the amount of dental care received.

Adolescent↗