bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ghrelin‐Induced Growth Hormone Release From Isolated Rat Anterior Pituitary Cells Depends on Intracellullar and Extracellular Ca2+ Sources
Authors: Yamazaki M. , Kobayashi H. , Tanaka T. , Kangawa K. , Inoue K. , Sakai T. 
Published: October 2004

AbstractGhrelin, a novel growth hormone (GH)‐releasing peptide, was isolated from the rat stomach as an endogenous ligand to the growth hormone secretagogues receptor. It is known that ghrelin stimulates the release of GH from the rat anterior pituitary gland, but the intracellular signal cascade in somatotrophs has not yet been clarified. In this study, using an isolated cell perifusion system, we examined whether ghrelin‐ and growth hormone‐releasing hormone (GHRH)‐induced GH secretion from rat pituitary cells depends on intra‐ and extracellular Ca2+ and voltage‐gated Ca2+ channels. For this purpose, we first measured ghrelin‐ or GHRH‐stimulated GH concentration following treatment with reduced extracellular Ca2+ and/or thapsigargin, an endoplasmic reticulum Ca2+ ATPase inhibitor. Reductions in the extracellular Ca2+ concentration to 0.25 mM and to 0 mM resulted in decreases in ghrelin‐stimulated GH secretion to 81% and 39% and decreases in GHRH‐induced GH secretion to 83% and 13%, respectively, compared to the levels in the case of 2.5 mM Ca2+ concentration, suggesting that extracellular Ca2+ is essential for both ghrelin‐ and GHRH‐induced GH secretion. Pretreatment with thapsigargin resulted in a reduction in ghrelin‐induced GH secretion to approximately 60% of the control level, but GHRH treatment had not effect on the GH secretion. Moreover, preincubation with thapsigargin and 0 mM extracellular Ca2+ concentration resulted in significant inhibition of GHRH‐ and ghrelin‐induced GH secretion. Subsequently, to determine whether ghrelin‐stimulated GH secretion was induced through voltage‐gated Ca2+ channels, we measured the ghrelin‐stimulated GH concentration following treatment with nifedipine, an L‐type Ca2+ channel inhibitor, and found that the amount of GH secretion was reduced to 44% of the control level. Furthermore, by replacement of extracellular Na2+ in the medium with N‐methyl‐d(–)‐glucamine, an impermeable molecule, GH secretion was reduced to 47%. In this study, we demonstrated that the GH‐stimulatory effect of ghrelin, unlike that of GHRH, is achieved through both intracellular and extracellular Ca2+ sources and that ghrelin‐induced extracellular Ca2+ influx involves an L‐type voltage‐gated Ca2+ channel and Na+ influx.
Timing of Thyroid Hormone Action in the Developing Brain: Clinical Observations and Experimental Findings
Authors: Zoeller R. T. , Rovet J. 
Published: October 2004

AbstractThe original concept of the critical period of thyroid hormone (TH) action on brain development was proposed to identify the postnatal period during which TH supplement must be provided to a child with congenital hypothyroidism to prevent mental retardation. As neuropsychological tools have become more sensitive, it has become apparent that even mild TH insufficiency in humans can produce measurable deficits in very specific neuropsychological functions, and that the specific consequences of TH deficiency depends on the precise developmental timing of the deficiency. Models of maternal hypothyroidism, hypothyroxinaemia and congential hyperthyroidism have provided these insights. If the TH deficiency occurs early in pregnancy, the offspring display problems in visual attention, visual processing (i.e. acuity and strabismus) and gross motor skills. If it occurs later in pregnancy, children are at additional risk of subnormal visual (i.e. contrast sensitivity) and visuospatial skills, as well as slower response speeds and fine motor deficits. Finally, if TH insufficiency occurs after birth, language and memory skills are most predominantly affected. Although the experimental literature lags behind clinical studies in providing a mechanistic explanation for each of these observations, recent studies confirm that the specific action of TH on brain development depends upon developmental timing, and studies informing us about molecular mechanisms of TH action are generating hypotheses concerning possible mechanisms to account for these pleiotropic actions.
Stabilization of asthma prevalence among adolescents and increase among schoolchildren (ISAAC phases I and III) in Spain*
Authors: García‐Marcos L. , Quirós A. Blanco , Hernández G. García , Guillén‐Grima F. , Díaz C. González , Ureña I. Carvajal , Pena A. Arnedo , Monge R. Busquets , Suárez‐Varela M. Morales , Varela A. López‐Silvarrey , Cabanillas P. Gómez , Garrido J. Batlles 
Published: October 2004

Background:  Most studies show a steep increase in asthma prevalence in the last decades, although few studies had applied the same methodology. Recent reports point out the possibility that the epidemic has come to an end. We have studied the prevalence of asthma in a very large sample of children, repeating the study eight years apart.Methods:  Repeated cross‐sectional studies using the International Study of Asthma and Allergies in Childhood (ISAAC) protocol in a sample of Spanish schoolchildren 6–7 (parent‐reported) and 13–14 (self‐reported) years old in 1994–95 (phase I) and 2002–2003 (phase III). The number of participants was 42 417 in phase I and 42 813 in phase III. The participation rate was over 87% (13–14 years) and 70% (6–7 years).Results:  The prevalence of wheezing in the previous year in children aged 13–14 years was 9.0 and 9.3% for boys and 9.6 and 9.2% for girls for phases I and III, respectively. Children 6–7 years of age showed a substantial increase in wheezing in the previous year (7.0 and 10.7% for boys and 5.3 and 8.2% for girls). Other symptoms and severity indexes followed the same patterns.Conclusions:  In the last 8 years, the prevalence of asthma has not changed in 13–14‐year‐old Spanish children but has increased substantially in 6–7‐year olds.
Increased allergen concentration enhances IFN‐γ production by allergic donor T cells expressing a peripheral tissue trafficking phenotype
Authors: Gardner L. M. , Spyroglou L. , O'Hehir R. E. , Rolland J. M. 
Published: October 2004

Background:  Clinically effective allergen‐specific immunotherapy correlates with decreased circulating allergen‐specific IL‐4+ T cells but increased IFN‐γ+ cells at sites of allergen challenge. Whether immunotherapy promotes trafficking of IFN‐γ+ T cells to peripheral tissues is unknown. As aeroallergen is administered at higher concentrations during immunotherapy than those encountered naturally, the effect of allergen concentration on adhesion molecule (CD62L and CD49d) and chemokine receptor (CCR3 and CCR5) expression by peripheral‐blood T cells was analysed in parallel with cytokine production.Methods:  House dust mite‐allergic donor peripheral blood mononuclear cells were cultured for 14 days with different allergen concentrations. Cytokine profiles of were analysed by flow cytometry.Results:  Cultures stimulated with 100 μg/ml house dust mite extract compared with 1 μg/ml had increased proportions and numbers of CD62Llo, CD49dhi or CCR5+ T cells expressing IFN‐γ. CCR3‐positive CD4+ and CD8+ T cell numbers were very low and did not differ between cultures. In contrast the proportions of ‘peripheral tissue trafficking’ CD4+ T cells expressing IL‐4 were decreased in cultures stimulated with high in comparison with low allergen concentration.Conclusion:  These results indicate the importance of achieving high allergen doses during immunotherapy to promote IFN‐γ production and expression of a ‘peripheral tissue trafficking’ phenotype by allergen‐specific CD4+ and CD8+ T cells. The net change in cytokine milieu at sites of allergen encounter would then down‐regulate clinical manifestations of allergic disease.
Geochemistry and Rb–Sr geochronology of the alkaline–peralkaline Narraburra Complex, central southern New South Wales; tectonic significance of Late Devonian granitic magmatism in the Lachlan Fold Belt
Authors: WORMALD R. J. , PRICE R. C. , KEMP A. I. S. 
Published: October 2004

Three suites of alkaline granite can be recognised in the Narraburra Complex at the triple junction of the Tumut, Giralambone–Goonumbla and Wagga Zones, central southern New South Wales. On the basis of K2O/Na2O ratios, biotite and hornblende–biotite potassic I‐type granites have been assigned to the Gilmore Hill (K2O/Na2O 1.00) and Barmedman Suites (K2O/Na2O > 1.2). These are metaluminous to weakly peraluminous suites that crystallised from high‐temperature, reduced magmas with the least fractionated members of each suite having high Ba and low Rb abundances compared to other Lachlan Fold Belt granites. Fractionated members of these suites have high abundances of high‐field‐strength elements, similar to those observed in A‐type granites. Arfvedsonite and aegirine–arfvedsonite granites have been assigned to the peralkaline Narraburra Suite. Granites from this suite have chemistry consistent with them being the intrusive equivalents of comendites and they are also similar in some respects to A‐type granites: they have, for example, particularly high abundances of Zr. The A‐type signature is, however, at least in part the result of strong fractionation. Total‐rock Rb–Sr isotopic analyses from both I‐type suites plot on the same isochron, giving an age of 365 ± 4 Ma (SrI = 0.70388 ± 53). A total‐rock isochron for the peralkaline Narraburra Suite gives a less well‐defined age of 358 ± 9 Ma (SrI = 0.7013 ± 80). The Late Devonian Rb–Sr ages may be emplacement ages or a result of resetting during fluid–rock interaction. Although granites of the Narraburra Complex have geochemical affinities with alkaline granites formed late in orogenic cycles, they post‐date arc magmatism by at least 75 million years and they formed in a within‐plate setting. Magmatism was related to localised reactivation of major faults (Gilmore Fault and the Parkes Thrust) in the region, and to partial melting involving both enriched mantle and Ordovician shoshonitic crustal components. Emplacement of the Narraburra Complex was contemporaneous with magmatism in the Central Victorian Magmatic Province and A‐type magmatism in eastern New South Wales. Collectively, all these magmatic events were related to extension post‐dating amalgamation of the western and central/eastern subprovinces of the Lachlan Fold Belt.
Nature and extent of Pliocene strandlines in southwestern Victoria and their application to Late Neogene tectonics
Authors: PAINE M. D. , BENNETTS D. A. , WEBB J. A. , MORAND V. J. 
Published: October 2004

Curvilinear Th/U anomalies evident on radiometric imagery over southwestern Victoria were plotted on topographic maps and the corresponding exposures investigated in the field. These exposures were found to be dominated by quartz‐rich ferruginous duricrusts, which, based upon detailed profile descriptions and petrographic studies, are interpreted as marginal‐marine sediments of the Dorodong Sands and Loxton–Parilla Sands. Similarly oriented linear magnetic anomalies evident on aeromagnetic imagery for the Branxholme area are coincident with concentrations of detrital ferruginous magnetic gravels. These are interpreted as having been derived from weathering profiles developed in the Dorodong Sands and may have subsequently been concentrated in swales between Dorodong Sands ridges. Thus the curvilinear Th/U anomalies and magnetic anomalies are both spatially and genetically related to prior shorelines or strandlines. Some of the strandlines are covered by 4 Ma basalts, and were deposited between 6.6 and 4 Ma, i.e. very Late Miocene to Early Pliocene. Elsewhere the strandlines have a more extended time range, with the youngest strandline allocated a ca 3.5 Ma age. Strandlines at Branxholme are also younger and are regarded as Mid‐Pliocene in age. The extent of the older shorelines suggests that the major Late Miocene – Pliocene marine transgression into the Murray Basin also covered most of southwestern Victoria, much further inland than previously recognised. The variable orientation of the oldest strandlines appears to reflect a phase of syndepositional uplift of the Dundas Tablelands, causing changes in the configuration of the regressing Pliocene shoreline. The strandlines can be used as a datum for Neogene tectonism, and indicate fault displacements of up to 180 m and total uplift of up to 300 m, although faulting in the north was less intense. Most tectonism was relatively short‐lived and probably occurred between 6 and 4 Ma, i.e. Early Pliocene; the 4 Ma basalts overlying the strandlines show no evidence of faulting. Earlier faulting in the Late Miocene initiated subsidence of the prominent Hamilton Graben (identified by subsurface mapping underneath the basalt), with further movement in the Early Pliocene during deposition of the Dorodong Sands.
Comparative evaluation of Sensititre® YeastOne vs. the NCCLS M27A protocol and E‐test for antifungal susceptibility testing of yeasts
Authors: Lombardi G. , Farina C. , Andreoni S. , Fazii P. , Faggi E. , Pini G. , Manso E. , Nanetti A. , Mazzoni A. 
Published: October 2004

SummaryA recently developed microdilution method (Sensititre® YeastOne) may represent a valid alternative to the National Committee for Clinical Laboratory Standards (NCCLS) method for routine testing. The Medical Mycology Committee of the Associazione Microbiologi Clinici Italiani (AMCLI) decided to evaluate its reproducibility and reliability compared with the NCCLS M27A protocol and the E‐test. Nineteen strains each of Candida albicans and Ca. parapsilosis, isolated from systemic infections, were tested against amphotericin B, flucytosine, ketoconazole, itraconazole, and fluconazole. All the participating laboratories tested the YeastOne panels, while the E‐test and the NCCLS method were performed by two laboratories each. Interlaboratory reproducibility showed a good correlation (from 95% for amphotericin B to 92.5% for flucytosine). The agreement between NCCLS and YeastOne ranged from 95 (ketoconazole and itraconazole) to 100% (amphotericin B and flucytosine), whereas the agreement between E‐test and YeastOne ranged from 72.5 (fluconazole) to 100% (amphotericin B and flucytosine). The Sensititre® YeastOne panels appear to be an excellent alternative to both the E‐test and the NCCLS protocol for antifungal susceptibility testing.
Detection of Cryptococcus neoformans var. grubii in honeybee (Apis mellifera) colonies
Authors: Ergin Ç. , Ilkit M. , Kaftanoǧlu O. 
Published: October 2004

SummaryThe plant flora has an important role in the ecology of Cryptococcus neoformans. It is estimated that the environmental spreading and contamination of human beings with this yeast occurs via contaminated particles of plants. Cultivation of canopy parts of plants in selective media is the most widely used isolation method of this yeast. Cryptococcus neoformans var. grubii was isolated from honeybee colonies in Eucalyptus forests but was not isolated from the places where this flora did not exist. Our results indicate that the occurrence of C. neoformans in honeybee colonies during the flowering season of Eucalyptus spp. trees can be an important bioindicator for environmental yeast presence. The screening of honeybee colonies is a practical and a rapid method for the monitoring of the C. neoformans presence in flowering plants.
Lethal otogenic Candida meningitis
Authors: Koch S. , Rudel B. , Tietz H.‐J. 
Published: October 2004

SummaryA 61‐year‐old woman with clinical signs of meningitis/encephalitis was admitted to hospital in a somnolent state. Inquiries with regard to the history revealed a chronic obstructive pulmonary condition which had been treated with prednisolone for a long time. There was a raised temperature with further signs of an acute inflammatory underlying disease and internal hydrocephalus. After performing trepanation, the symptoms of raised intercerebral pressure ceased. Candida albicans could be detected microbiologically in the cerebrospinal fluid. There was no pneumonia at the time of admission. Despite instituting immediate intensive care with administration of antibiotics and antimycotics, the patient died 11 days after inpatient admission. Autopsy revealed a C. albicans mycosis originating from the right middle ear with extensive suppurative meningitis, which was the immediate cause of death. Confluent bronchopneumonia had developed in both lower lung lobes at the time of death, but did not show any signs of mycosis and had contributed indirectly to the death of the patient.
Impaired nitric oxide‐ and endothelium‐derived hyperpolarizing factor‐dependent dilation of renal afferent arteriole in Dahl salt‐sensitive rats
Authors: OZAWA YURI , HAYASHI KOICHI , KANDA TAKESHI , HOMMA KOICHIRO , TAKAMATSU ICHIRO , TATEMATSU SATORU , YOSHIOKA KYOKO , KUMAGAI HIROO , WAKINO SHU , SARUTA TAKAO 
Published: October 2004

SUMMARY:Background and Aims:  We previously demonstrated that acetylcholine elicited nitric oxide‐dependent sustained and endothelium‐derived hyperpolarizing factor (EDHF)‐dependent transient dilation of afferent arterioles. The present study examined whether free radicals interacted with nitric oxide‐dependent and EDHF‐dependent vasodilator mechanisms in renal microvessels of salt‐sensitive hypertension, using the isolated perfused hydronephrotic kidney.Methods and Results:  Following the pretreatment with indomethacin (100 µmol/L) with or without nitro‐ l‐arginine methylester (100 µmol/L), the effect of acetylcholine on noradrenaline (0.3 µmol/L)‐induced constriction was evaluated in kidneys from Dahl salt‐sensitive and salt‐resistant rats. Although acetylcholine (0.01–10 µmol/L) caused dose‐dependent and sustained vasodilation of afferent arterioles, attenuated dilation was observed in Dahl salt‐sensitive rats, compared with that in salt‐resistant rats (58 ± 4 vs 101 ± 11% reversal at 10 µmol/L acetylcholine). In the presence of nitro‐ l‐arginine methylester, acetylcholine elicited only transient dilation, with vasodilator response blunted in Dahl salt‐sensitive rats (64 ± 4 vs 100 ± 9% reversal at 10 µmol/L acetylcholine). Furthermore, chronic (8–10 weeks) treatment with tempol caused partial restoration of acetylcholine (10 µmol/L)‐induced sustained arteriolar dilation (71 ± 3% reversal), but complete reversal of transient dilation (92 ± 4% reversal). Finally, acute treatment with tempol not only improved the sustained component of the acetylcholine‐induced dilation but also restored the impaired responsiveness of transient dilation in Dahl salt‐sensitive rats.Conclusion:  Both sustained (nitric oxide‐mediated) and transient (EDHF‐mediated) components of acetylcholine‐induced afferent arteriolar dilation were attenuated in Dahl salt‐sensitive rats, which was attributed, in part, to enhanced free radical activity. A reversal of the sustained and transient vasodilation by the acute tempol treatment suggests possible interaction between free radicals and EDHF as well as increased bioavailability of nitric oxide.
Medicinal herbal extracts – renal friend or foe? Part one: The toxicities of medicinal herbs
Authors: WOJCIKOWSKI KEN , JOHNSON DAVID W , GOBÉ GLENDA 
Published: October 2004

SUMMARY:In recent years, an increasing percentage of people from industrialized countries have been using complementary and alternative medicines (CAM). This, combined with numerous warnings regarding the potential toxicity of these therapies, suggests the need for practitioners to keep abreast of the reported incidence of renal toxicity caused by the ingestion of medicinal herbs. The goal of the present two‐part series, on the toxic or beneficial effects of medicinal herbs on renal health, is to provide practitioners with a summary of the most recent information as well as the means by which evidence for benefit or toxicity has been found. In this first article, we explore in vivo evidence of toxicity. Included are nephrotoxicity from aristolochic acid and other components within herbs, herb–drug interactions resulting in adverse renal effects, and renal toxicity from contaminants within the extracts. The review aims to provide a guide to encourage future toxicity studies and rigorous clinical trials.
Low protein diet causes a decrease in serum concentrations of leptin and tumour necrosis factor‐alpha in patients with conservatively treated chronic renal failure
Authors: KOZŁOWSKA LUCYNA , ROSOŁOWSKA‐HUSZCZ DANUTA , RYDZEWSKI ANDRZEJ 
Published: October 2004

SUMMARY:Background:  Chronic renal failure (CRF) provokes derangement in various hormonal regulations of food intake and energy expenditure. In the present study, we have examined the effect of a low protein, low phosphorus diet on circulating levels of leptin, tumour necrosis factor (TNF)‐alpha, and insulin in patients with CRF.Methods:  Seventeen male, non‐diabetic subjects with conservatively treated CRF (estimated creatinine clearance 39.5 ± 11.1 mL/min), and proteinuria below 2 g/day were prospectively studied. Measurements of hormonal, metabolic and anthropometric parameters were performed before and after 16 weeks of dietary treatment (protein 0.6 g/kg of ideal body mass, 30% of calories derived from fat, 62% of calories derived from carbohydrates and 10 mg/kg of phosphorus). Actual dietary intake in patients was measured by using 3‐day food records and was supervised by the dietician.Results:  Body mass index and body fat mass remained unchanged during the 4 months of dietary treatment. Urea, leptin, and TNF‐alpha serum concentrations decreased significantly.Conclusions:  A low protein, low phosphorus diet reduces TNF‐alpha and leptin levels in plasma. The effect on leptin appears not to be mediated by an insulin‐dependent mechanism.
ENDOSCOPIC ULTRASOUND AND FINE‐NEEDLE ASPIRATION FOR PANCREATIC CANCER
Authors: Wallace Michael B , Woodward Timothy , Raimondo Massimo 
Published: October 2004

Background:  Accurate staging of pancreatic cancer is essential for surgical planning, and identification of locally advanced and metastatic disease that is incurable by surgery. Advances in EUS, CT, and PET have improved the accuracy of staging and reduced the number of incomplete surgical resections. Tissue acquisition is necessary in non‐surgical cases when chemo‐radiotherapy is considered. The complex regional anatomy of the pancreas makes cytologic diagnosis of malignancy at this region difficult without exploratory surgery. Although CT‐guided fine‐needle aspiration (FNA) is used for this purpose, reports of an increased risk of peritoneal dissemination of cancer cells and a false negative rate of nearly 20% makes this a less than ideal choice. The ability to position the EUS‐transducer in direct proximity to the pancreas by means of stomach and the duodenum, combined with the use of FNA, increases the specificity of EUS in detecting pancreatic malignancies.Methods:  The current literature regarding the accuracy of EUS with FNA in the evaluation of pancreatic cancer is reviewed.Results:  EUS accuracy for tumor (T) staging ranges from approximately 78–94% and nodal (N) stage accuracy between 64 and 82%. EUS also enables FNA of lesions that are too small to be identified by CT or MRI, or too close to vascular structures to safely allow percutaneous biopsy. The accuracy for detecting invasion into the superior mesenteric artery and vein is lower than that for detecting portal or splenic vein invasion, especially for large tumors. EUS permits delivery of localized therapy such as celiac plexus neurolysis for pain control and direct intralesional injection of antitumor therapy.Conclusions:  EUS in combination with FNA is a highly accurate method of preoperative staging of pancreatic cancer especially those too small to characterize by CT or MRI, and has the ability to obtain cytological confirmation.