bluuebunny/crossref_metadata_2025_split huggingface dataset:
An exact solution to the moving boundary problem with fractional anomalous diffusion in drug release devices
Authors: Liu J.Y. , Xu M.Y. 
Published: December 2003

AbstractAn exact solution to the moving boundary problem with fractional anomalous diffusion (in time) in drug release devices is presented by means of fractional Green's function and Wright function in this paper. The result given by this paper coincides with the known semi‐empirical Ritger‐Peppas' formula in controlled drug release system [4]. For convenience of use, an approximate expression of the amount of drug released from polymeric matrix with high accuracy is given out at the end of the paper.
Effect of Helicobacter pylori Infection in Barrett’s Esophagus and the Genesis of Esophageal Adenocarcinoma
Authors: Clark Geoffrey W.B. 
Published: November 2003

AbstractThe relation between Helicobacter pylori and gastroesophageal reflux disease is unclear. Recent reports have suggested a possible protective role for H. pylori, particularly in preventing the complications of gastroesophageal reflux disease (GERD). The purpose of this article is to present a brief overview of the recent literature regarding the role of H. pylori in the genesis of the complications of GERD, focusing on Barrett’s esophagus and esophageal adenocarcinoma. The prevalence of H. pylori infection in the population of the West is around 40% and is not different in cohorts of patients with GERD. When the infection induces pangastritis or corpus‐predominant gastritis, there may be concomitant reduced gastric acid secretion. Eradication of the bacteria in this subgroup of patients may enhance gastric acid secretion and provoke reflux symptoms. H. pylori organisms do not colonize the specialized intestinal metaplasia characteristic of Barrett’s esophagus. H. pylori infection rates in gastric mucosa of patients with Barrett’s esophagus occur at a similar or slightly lower frequency than is found in controls. Gastric infection with cagA‐positive strains of H. pylori appears to be uncommon in patients with Barrett’s esophagus. Furthermore, epidemiologic studies indicate that cagA‐positive strains are protective against esophageal adenocarcinoma. Several investigators have proposed that the decreasing prevalence of H. pylori infection might be an important factor in the rising incidence of this tumor.
Urantide: an ultrapotent urotensin II antagonist peptide in the rat aorta
Authors: Patacchini Riccardo , Santicioli Paolo , Giuliani Sandro , Grieco Paolo , Novellino Ettore , Rovero Paolo , Maggi Carlo Alberto 
Published: November 2003

In this study we describe the ability of two human urotensin‐II (hU‐II) derivatives [Pen5,Orn8]hU‐II(4–11) and [Pen5,DTrp7,Orn8]hU‐II(4–11) (urantide) to block hU‐II‐induced contractions in the rat isolated thoracic aorta. Both compounds competitively antagonized hU‐II‐ induced effects with pKB=7.4±0.06 (n=12) and pKB=8.3±0.09 (n=12), respectively. In contrast, neither [Pen5,Orn8]hU‐II(4–11) nor urantide (1 μM each) was able to modify noradrenaline‐ or endothelin 1‐induced contractile effects. At micromolar concentrations, [Pen5,Orn8]hU‐II(4–11) produced weak (25% of hU‐II maximum) agonist responses in the rat aorta, whereas urantide was totally uneffective as agonist up to 1 μM. In addition, [Pen5,Orn8]hU‐II(4–11) and urantide displaced [125I]urotensin II from specific binding at hU‐II recombinant receptors (UT receptors) transfected into CHO/K1 cells (pKi=7.7±0.05, n=4 and pKi=8.3±0.04, n=4, respectively). To our knowledge, urantide is the most potent UT receptor antagonist so far described, and might represent a useful tool for exploring the (patho)physiological role of hU‐II in the mammalian cardiovascular system.British Journal of Pharmacology (2003) 140, 1155–1158. doi:10.1038/sj.bjp.0705555
Increased effects of C‐type natriuretic peptide on contractility and calcium regulation in murine hearts overexpressing cyclic GMP‐dependent protein kinase I
Authors: Wollert Kai C , Yurukova Sevdalina , Kilic Ana , Begrow Frank , Fiedler Beate , Gambaryan Stepan , Walter Ulrich , Lohmann Suzanne M , Kuhn Michaela 
Published: November 2003

C‐type natriuretic peptide (CNP) and its receptor guanylyl cyclase (GC‐B) are expressed in the heart and modulate cardiac contractility in a cGMP‐dependent manner. Since the distal cellular signalling pathways remain unclear, we evaluated the peptide effects on cardiac function and calcium regulation in wild‐type (WT) and transgenic mice with cardiac overexpression of cGMP‐dependent protein kinase I (PKG ITG).
In isolated, perfused working WT hearts, CNP (10 nM) provoked an immediate increase in the maximal rates of contraction and relaxation, a small increase in the left ventricular systolic pressure and a decrease in the time of relaxation. These changes in cardiac function were accompanied by a marked increase in the levels of Ser16‐phosphorylated phospholamban (PLB).
In PKG ITG hearts, the effects of CNP on cardiac contractility and relaxation as well as on PLB phosphorylation were markedly enhanced.
CNP increased cell shortening and systolic Cai2+ levels, and accelerated Cai2+ decay in isolated, Indo‐1/AM‐loaded WT cardiomyocytes, and these effects were enhanced in PKG I‐overexpressing cardiomyocytes.
8‐pCPT‐cGMP, a membrane‐permeable PKG activator, mimicked the contractile and molecular actions of CNP, the effects again being more pronounced in PKG ITG hearts. In contrast, the cardiac reponses to β‐adrenergic stimulation were not different between genotypes.
Taken together, our data indicate that PKG I is a downstream target activated by the CNP/GC‐B/cGMP‐signalling pathway in cardiac myocytes. cGMP/PKG I‐stimulated phosphorylation of PLB and subsequent activation of the sarcoplasmic reticulum Ca2+ pump appear to mediate the positive inotropic and lusitropic responses to CNP.

British Journal of Pharmacology (2003) 140, 1227–1236. doi:10.1038/sj.bjp.0705567
Role of buffalo in the socioeconomic development of rural Asia: Current status and future prospectus
Authors: NANDA Amarjit Singh , NAKAO Toshihiko 
Published: November 2003

ABSTRACTBuffalo has been an integral part of livestock agriculture in Asia for over 5000 years producing draft power, milk, meat and hides. Even today, 153 million buffalo provide 76 734 759 t of milk and 3 089 875 t of meat, and in several countries, up to 30% of the draft power for agricultural operations. Unfortunately, however, the species did not receive the attention of the policy makers and the researchers in accordance with its merits, which resulted in buffalo population decline in several eastern Asian countries. The present review highlights the importance of buffalo to the economic and social fabric, especially of the small and landless rural poor, of several countries in Asia. Some major national and international efforts being made to improve buffalo production have also been cited.
Amino acid nutrition in egg production industry
Authors: ISHIBASHI Teru , YONEMOCHI Chisato 
Published: November 2003

ABSTRACTThe egg production industry is facing various problems that need to be solved. For amino acid nutrition to achieve scientific and economical feeding of laying hens, it is necessary to elucidate the content, digestibility, or availability of nutrients of feedstuffs and feeds and the requirement of amino acids for laying hens. In addition, improvement to quality of eggs and meat of spent hens, methods of management and development of new feedstuffs are essential. For sustainable animal production, decrease in excreta and animal welfare should be studied. The real‐time determination of content and digestibility of amino acids in feedstuffs are essential for formation of feeds. Recent advances in the near infrared reflectance analysis will be able to determine the content, digestibility and availability of nutrients in feedstuffs and feeds, if we have a supplemental amount of conventional analysis to define the calibration population. The amino acid requirements are affected by various factors. Therefore the method to quickly and exactly determine amino acid requirements in response to various factors is necessary. By using plasma free amino acid concentration as a criterion, it is possible to determine amino acid requirements in various conditions of laying hens within a short experimental period, repeatedly using the same animals. Because the amino acid requirements differ among individual animals, it should be expressed as grams per hen per day. Practically, it is impossible to formulate various feeds for individual hens. The various expressions have been developed and these expressions have advantages and disadvantages. The nitrogen excretion of laying hens is easily reduced by reducing dietary nitrogen levels and restricting the feed intake. The availability of amino acid may be improved by feeding management, and supplementing enzyme, but the quality of eggs and meat of spent hens and welfare of laying hens are not affected by amino acid nutrition.
Growth hormone treatment affects brain neurotransmitters and thyroxine
Authors: Burman P. , Hetta J. , Wide L. , Månsson J‐E. , Ekman R. , Karlsson F. A. 
Published: November 2003

OBJECTIVE Binding sites specific for growth hormone have been identified in the brain, but the action of GH on the central nervous system is still poorly understood.DESIGN In a double‐blind, placebo‐controlled 21‐month trial with a cross‐over design, with each treatment period lasting for 9 months, we investigated the long‐term effect of GH on the cerebrospinal fluid (CSF) concentrations of some brain neurotransmitters and thyroid hormones of importance for mood and cognition.PATIENTS Twenty‐four patients with documented GH deficiency acquired in adult life took part.RESULTS Analysis of CSF collected at the end of the two treatment periods showed that the GH concentration was related to the administered dose of rhGH (r = 0.56, P = 0.0044). After rhGH treatment the concentration of the dopamine metabolite homovanillic acid (HVA) had decreased from 218 ± 80 to 193 ± 82 nmol/l (P = 0.002) and that of the excitatory acid aspartate had increased from 233 ± 81 to 313 ± 116 nmol/l (P = 0.032). No effects were observed on the concentrations of 5‐hydroxyindole‐acetic acid (the serotonin metabolite) and of 3‐methoxy‐4‐hydroxyphenyl glycol (the noradrenaline metabolite), or on those of glutamate, glycine and β‐endorphin. However, both CSF and serum levels of free T4 decreased, from 19.8 ± 6.1 to 16.6± 5.7 nmol/l (P = 0.0002) and 17.0 ± 5.0 to 13.7 ± 4.3 nmol/l (P = 0.0001), respectively. The concentration of total T3 was not measurable in CSF but increased in serum from 1.41 to 1.53 nmol/l (P = 0.01).CONCLUSION The study demonstrates a passage of GH from the circulation into the CSF. The observed changes in homovanillic acid and free T4 are similar to those reported after successful treatment of depressive disorders with antidepressant drugs, and may reflect a beneficial effect of GH on mood and behaviour.
Characterization of inhibin immunoreactivity in post‐menopausal women with ovarian tumours
Authors: Burger H. G. , Robertson D. M. , Cahir N. , Mamers P. , Healy D. L. , Jobling T. , Groome N. 
Published: November 2003

BACKGROUND AND OBJECTIVE We have previously reported elevated serum immunoreactive inhibin (INH) levels in patients with ovarian malignancies, particularly granulosa cell and mucinous tumours. The present study was designed to compare INH measurements using a heterologous radioimmunoassay with cross‐reactivity for inhibin α‐subunit derived peptides with measurements obtained using a new ELISA specific for dimeric inhibin‐A. It was hypothesized that granulosa cell tumours may secrete significant quantities of inhibin‐A whereas mucinous tumours were unlikely to do so because of the lack of a relation between INH and FSH measurements in the latter group.DESIGN Serum samples obtained from women found to have ovarian cancer were assayed using the heterologous radioimmunoassay (the Monash assay) and using an ELISA specific for dimeric inhibin (the Groome assay) and the results were compared.PATIENTS Samples for assay were available from 69 normal post‐menopausal control women, 12 patients with mucinous tumours of the ovary, 26 with serous tumours, 7 with granulosa cell tumours and 8 with various other ovarian tumours. Patients were post‐menopausal or had been subjected to bilateral oophorectomy at the time these samples were collected.MEASUREMENTS The Monash and Groome assays were carried out as described previously. The upper limit of normal for post‐menopausal women in the Monash assay was 122 U/l and for the Groome assay was calculated to be 32 ng/l.RESULTS Among the 69 normal subjects, 4 were found to have elevated inhibin levels using the Monash RIA (133–190 U/l) and 4 were found to have elevated levels in the Groome ELISA (45.5–55.3 ng/l). Among 12 patients with mucinous tumours, 10 (83%) had elevated inhibin levels using the Monash assay but only 3 (25%) had elevated levels with the Groome assay (P < 0.005). Among 26 with serous tumours, 15 (58%) had elevated levels in the Monash assay but only 1 (4%) in the Groome assay (P < 0.001). Among 7 samples from patients with granulosa cell tumours, 100% were elevated in the Monash assay and 71% in the Groome assay (NS, non‐significant). In a miscellaneous group of tumours all 8 had elevated levels in the Monash assay and 2 in the Groome assay (P < 0.001).CONCLUSIONS It was concluded that in normal post‐menopausal subjects, INH is generally undetectable or present at low levels, consistent with the loss of ovarian function. The majority of granulosa cell tumours appear to secrete significant amounts of dimeric inhibin‐A, whereas mucinous tumours secrete predominantly other forms of INH, presumably related to the α‐subunit. Serous tumours may also secrete inhibin‐related peptides but not dimeric inhibin‐A. The nature of the inhibin related peptides produced by epithelial ovarian cancers remains to be characterized.
Polymorphism of glycogen synthetase gene in polycystic ovary syndrome
Authors: Rajkhowa M. , Talbot J. A. , Jones P. W. , Clayton R. N. 
Published: November 2003

OBJECTIVE Polycystic ovary syndrome is a heterogeneous disorder associated with a moderate degree of insulin resistance and a higher risk of developing NIDDM. The exact mechanism of insulin resistance is unclear. This study examines the frequency of an Xbal polymorphism of the glycogen synthetase gene (A2 allele) as a marker of insulin resistance and seeks to relate the presence of the A2 allele to indices of insulin sensitivity in women with polycystic ovary syndrome (PCOS).METHODS Insulin sensitivity was assessed by fasting insulin measurements, as well as following oral glucose tolerance test. An i.v. insulin tolerance test was performed to measure the rate of endogenous blood glucose disposal following an i.v. bolus of insulin. Restriction fragment length polymorphism was performed with Xbal digestion of PCR amplified product to detect the presence of A1 and A2 allele.PATIENTS Seventy‐one obese (BMI > 25.1) and 19 non‐obese (BMI < 25) women with PCOS, and 62 controls (33 obese and 29 non‐obese) participated in the study.RESULTS Obese PCOS had significantly higher fasting insulin ( P = 0.002) compared to obese controls. There was no difference between non‐obese PCOS and controls. Twenty per cent of obese PCOS had impaired glucose tolerance.The A1A2 genotype was detected in 16 of the 150 (10.7%) subjects examined. Of these, 11/88 (12.5%) were PCOS and 5/62 (8%) were controls. The A2A2 genotype was not present in any of the subjects. The A1A2 genotype was not detected in any of the subjects with impaired glucose tolerance. There was no significant difference in the incidence of the A1A2 genotype between PCOS and controls or between the individual groups. There was no association between the presence of the A1A2 genotype and indices of insulin sensitivity.CONCLUSION The Xbal polymorphism (A2 allele) of the glycogen synthetase gene was not over represented in the PCOS subject and did not relate to the indices of insulin sensitivity or glucose intolerance.
Somatic mutations in the RET proto‐oncogene in sporadic medullary thyroid carcinoma
Authors: Marsh Debbie J. , Learoyd Diana L. , Andrew Scott D. , Krishnan Lalitha , Pojer Ruth , Richardson Anne‐Louise , Delbridge Leigh , Eng Charis , Robinson Bruce G. 
Published: November 2003

OBJECTIVE We have determined the frequency of specific mutations in the RET proto‐oncogene in sporadic medullary thyroid carcinomas (MTCs) and correlated the presence or absence of a codon 918 mutation with the clinical characteristics of these tumours.DESIGN Thirty paraffin‐embedded sporadic MTCs and two frozen MTCs were collected for analysis of specific mutations in the RET proto‐oncogene in codons 609, 611, 618 and 620 (exon 10); 630 and 634 (exon 11); 768 (exon 13); 883 (exon 15) and 918 (exon 16). A novel primer was designed which introduced a restriction site for RsaI in the presence of the specific codon 918 mutation (ATG → ACG) in these tumour samples. A ‘clinical‐genetic’ correlation was performed comparing the presence or absence of the codon 918 mutation with the following clinical characteristics: age at diagnosis, tumour size, presence or absence of metastases, MTC related morbidity, and base line calcitonin levels at diagnosis or most recent follow‐up.PATIENTS Patients were classified as having sporadic MTC if there was no family history of C‐cell hyperplasia, MTC, phaeochromocytoma or parathyroid disease. Retrospective review of patient records enabled complete clinical data to be obtained in 28 of 32 patients.MEASUREMENTS Base line calcitonin levels were measured by radioimmunoassay or calcitonin enzyme linked immunoassay. Cysteine codons in exons 10 and 11, specifically codons 609, 611, 618, 620, 630 and 634, were screened for the presence of mutations by sequence analysis. Specific mutations occurring at codons 768, 883 and 918 were screened for by restriction endonuclease digestion of PCR products.RESULTS The mutation at codon 918ATG → ACG was found in 21 of 32 (66%) MTCs and the mutation at codon 883GCT → TTT was found in one of 32 MTCs. Where possible, the presence of ‘germline‐type’ mutations in codons 609, 611, 618, 620, 630 and 634 were excluded. Ten MTCs did not have a mutation in codons 768, 883 or 918 of the RET proto‐oncogene. The presence or absence of the somatic mutation at codon 918 did not correlate with any of the above clinical characteristics.CONCLUSION Somatic mutations in the RET proto‐oncogene occur frequently in sporadic MTCs.
Steroids in human intrauterine fluids of early pregnancy
Authors: Atkinson G. , Campbell D. J. , Cawood M. L. , Oakey R. E. 
Published: November 2003

OBJECTIVE Little is known of the hormone environment of the developing early human embryo. We have therefore measured selected steroids in the intrauterine fluids of early pregnancy.DESIGN Measurement of progesterone, 17α‐hydroxyprogesterone, oestradiol‐17β, testoste rone, androstenedione, cortisol and dehydroepiandrosterone sulphate in matched samples of coelomic fluid, amniotic fluid and maternal serum collected before pregnancy termination from 12 women between 8 and 12 weeks gestation.RESULTS Mean concentrations of progesterone, oestradiol‐17β and 17α‐hydroxyprogesterone in coelomic fluid were respectively 20, 6 and 2 times greater than in maternal serum and 8, 13 and 2.6 times those in amniotic fluid. Concentrations of testosterone and androstenedione were highest in maternal serum and lowest in amniotic fluid. Cortisol and dehydroepiandrosterone sulphate were found in intrauterine fluids only at the limit of detection but in normal concentrations in maternal serum.CONCLUSIONS Coelomic fluid contains relatively high concentrations of progesterone, oestradiol‐17β and 17α‐hydroxyprogesterone which may be synthesized locally. Amniotic fluid contains lower concentrations of steroids (other than progesterone) than are found in coelomic fluid or maternal serum. Free diffusion of steroids across the amnion appears limited. This may constitute a mechanism to protect the embryo from unwanted exposure to biologically active steroids.
A comparison between short ACTH and insulin stress tests for assessing hypothalamo‐pituitary‐adrenal function
Authors: Ammari F. , Issa B. G. , Millward E. , Scanlon M. F. 
Published: November 2003

OBJECTIVE Insulin‐induced hypoglycaemia is the standard method for assessment of the hypothalamo‐pituitary‐adrenal (HPA) axis of patients with pituitary or hypothalamic disease. It has been claimed that a normal cortisol response to the 30‐minute ACTH stimulation test (AST) obviates the need to perform the insulin stress test (IST) in these patients. The objective of our study was to compare both tests in a group of consecutive patients with pituitary disease.SUBJECTS AND METHODS Thirty patients with pituitary disease were evaluated by standard IST (0.1 U of soluble insulin/kg body weight,i.v.) after fasting from midnight and AST (250μg synacthen, i.v.). In the IST, a plasma glucose of <2.2mmol/l was taken as the hypoglycaemic threshold and blood was collected at 0, 30, 60, 90 and 120minutes. In the AST blood was collected at 0 and 30minutes. Serum cortisol was measured by standard radioimmunoassay and glucose by the glucose oxidase method. Cortisol responses to the stimuli were compared at cut‐off levels of 550, 500, 450 and 400nmol/l.RESULTS At 550nmol/l, out of 30 patients, 17 showed an abnormal IST of whom 9 had normal responses to AST (53%). At 500nmol/l, 12 patients had an abnormal IST of whom 6 had normal AST (50%). At 450nmol/l, of 9 patients with an abnormal IST, 5 had a normal AST (56%). At 400nmol/l, 5 patients had an abnormal IST all of whom (100%) showed a normal AST.CONCLUSION There is a clear discrepancy between the results of the two tests at different cortisol cut‐off levels. The ACTH stimulation test is not reliable for assessing the HPA axis in patients with pituitary disease and the insulin stress test remains the standard method.