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D Huber

Publications and source records attributed to D Huber.

At least 37 records · Page 2Linked to original sources

1,25(OH)2-vitamin D3 reduces spontaneous and hypocalcemia-stimulated pulsatile component of parathyroid hormone secretion.

To investigate the effects of 1,25(OH)2-vitamin D3 (1,25(OH)2D3) on pulsatile parathyroid hormone (PTH) release, minute-to-minute intact PTH secretion was examined in nine healthy adults under baseline conditions and during hypocalcemia (sodium citrate clamp) before and after 5 d of oral 1,25(OH)2D3 treatment (1 microgram/d). In addition, acute effects of 1,25(OH)2D3 were examined by a single intravenous bolus of 2 micrograms of 1,25(OH)2D3. Pulsatile and tonic PTH secretion rates were calculated by the multiparameter deconvolution technique. During baseline, 68% of circulating PTH was attributable to tonic, and 32% to pulsatile, secretion. During induction of hypocalcemia, a selective increase in pulsatile secretion (+1100%), mediated by a combined increase in burst frequency and burst mass, was observed. During the subsequent steady-state hypocalcemic period, burst frequency and mass decreased and tonic secretion increased to 3 times the baseline level. Intravenous 1,25(OH)2D3 did not affect the temporal pattern of PTH secretion. In contrast, oral 1,25(OH)2D3 decreased baseline plasma PTH by 30% without a detectable change in Ca2+. This suppression was accounted for mainly by a decrease in PTH burst frequency. During hypocalcemia induction, a significantly lower (30%) increase in burst mass occurred compared with the pretreatment study. During steady-state hypocalcemia, PTH burst mass (-45%) and pulsatile (-50%) and total (-35%) secretion rate were lower than before treatment. In conclusion, acute hypocalcemia selectively increases pulsatile PTH release by stimulating both burst frequency and mass via a Ca2+ rate-sensitive mechanism. Oral 1,25-(OH)2D3 suppresses pulsatile baseline PTH release and reduces the pulsatile secretory capacity of the parathyroids during a hypocalcemic stimulus.

Administration, Oral↗

Dolphin morbilliviral infection from the Mediterranean Sea did not spread into the Adriatic Sea.

In July of 1990, a mass mortality of striped dolphins due to morbillivirus infection had begun in the western Mediterranean. By 1992, the infection had spread to the eastern Mediterranean and the Aegean Sea. Other dolphin species in the Mediterranean were not found to have died due to this infection, although it is possible for many species of marine mammals to be infected. In 1994, it was published that morbillivirus infection had caused Atlantic bottlenose dolphin mortality in the USA. Although striped dolphins are not residents of the Adriatic Sea, it was hypothesised that the infection could have spread from them to Adriatic bottlenose dolphins. From October 1990 through April 1997, 16 dolphin carcasses found along the Croatian Adriatic coast were examined. Tissues were examined by light microscopy for syncytia and inclusion bodies, histopathologic lesions characteristic of dolphin morbillivirus infection, and by detection of morbilliviral RNA by a reverse transcriptase polymerase chain reaction (RT-PCR). No signs of morbillivirus infection were found in the examined animals. It was concluded that this infection had not spread to dolphins of the Adriatic Sea up until that date.

Animals↗

Nursing Management Minimum Data Set (NMMDS).

The Nursing Management Minimum Data Set (NMMDS) is the research-based management data set that meets the nurse executives need for a specific nursing management data capture system that will produce accurate, reliable, and useful data for decision making. The authors update the development of the NMMDS and discuss the 17 NMMDS across-settings elements. Also discussed are the applications of the NMMDS to clinical practice and some ways in which the NMMDS can benefit both nurses and patient/client care.

Continuity of Patient Care↗

Effects of sex, age, capturing method, and season on serum chemistry values of brown bears in Croatia.

Sixty seven serum samples collected from 43 European brown bears (Ursus arctos) from Croatia were tested for < or = 31 serum chemistry parameters. Results were grouped and compared by bears origin (method of capture), sex, age, mass, and season sampled. Greatest differences were found between captive and free-living bears, and minor differences were found when sex, age, mass, or season of sampling were compared. Creatine kinase was significantly different among three categories of bears with the highest mean value of 924 IU/l in snare captured free-living bears compared to 67.8 IU/l in captive ones. Results of these tests provide reference values for European brown bears.

Age Determination by Teeth↗

Colour duplex ultrasonography versus angiography in the diagnosis of lower-extremity arterial disease.

Colour duplex scanning is reported to be an accurate non-invasive tool for the diagnosis of lower-extremity arterial disease. The authors at the South Coast Vascular Laboratory have conducted a prospective audit to determine the efficacy of colour duplex scanning in a vascular surgical practice. The aims of this prospective trial were to compare the accuracy of colour duplex scanning with intra-arterial digital subtraction angiography (DSA) in the localization and classification of aortoiliac and femoropopliteal artery disease. Ninety-one lower limbs in 50 patients were evaluated independently by colour duplex scanning and DSA. The lower-limb vasculature was divided into eight segments: infrarenal aorta, common iliac artery, external iliac artery, common femoral artery, proximal, middle and lower thirds of the combined length of the superficial femoral and above-knee popliteal artery, and lastly the below-knee popliteal artery. A total of 558 arterial segments were examined. The Kappa value of duplex scanning compared with 'gold standard' DSA was 0.57. For detecting haemodynamically significant arterial lesions of > 50% reduction in diameter, duplex scanning had a sensitivity of 75%, specificity of 90%, positive predictive value of 77% and negative predictive value of 89% compared with DSA. The level of accuracy obtained does not support the use of duplex as a sole method of investigation for lower-extremity arterial disease in the authors' case. However, the high negative predictive value of colour duplex may be useful in excluding haemodynamically significant disease. This study emphasizes the importance of prospective auditing to determine individual accuracy with duplex examination for arterial disease, and enables clinical decision making to be based on tests with a known accuracy.

Angiography, Digital Subtraction↗

Outcomes of an adjunct executive appointment for faculty.

The Council on Graduate Education for Administration in Nursing (CGEAN) was established to further develop and improve graduate education for administration in nursing. The Council seeks to identify the nature and direction of education for administration in nursing in various healthcare systems, providing guidelines for programs offering administration. A major goal of CGEAN is facilitating dialogue between nursing service administrators and graduate level educators who are engaged in teaching and research related to administration in nursing. This column, sponsored by the members of the Council, analyzes and responds to position statements and trends related to the delivery of health services and graduate education for administrators in nursing.

Education, Nursing↗

Colour-coded duplex ultrasonography in selection of patients for transluminal angioplasty.

Transluminal angioplasty can be used to relieve symptomatic lower extremity arterial disease with minimal morbidity. This prospective study compares the accuracy of colour-coded duplex ultrasonography with intra-arterial digital subtraction angiography in selection of femoro-popliteal lesions for angioplasty. Isolated, short (< 6 cm) and haemodynamically significant stenosis (> 50% reduction in diameter) were considered for angioplasty. Colour-duplex selection and exclusion was in agreement with angiography in 68 out of 86 lower limbs (79%). The sensitivity, specificity, positive and negative predictive value of colour duplex compared with angiography yielded values of 60.9, 87.5, 60.9 and 85.7%, respectively. The discrepancy between colour duplex and digital subtraction angiography can be partly explained by the tendency of duplex to underestimate the severity and length of disease. It is concluded that colour-coded duplex can be used as a screening tool for lower extremity arterial disease to select appropriate lesions for endovascular procedures. The accuracy of duplex in the present study was not perfect and the decision for further intervention should be based on clinical grounds.

Angiography, Digital Subtraction↗

Immunocytochemical localization of Ca(2+)-dependent protease from Allomyces arbuscula.

The Ca(2+)-dependent protease antisera and the purified specific antibodies from Allomyces arbuscula have shown very specific recognition when blotted against the total protein extract or the purified 43-40 kDa Ca(2+)-dependent protease from this aquatic fungus. By immunoblotting and immunofluorescence techniques using specific antibodies, we have shown that the enzyme activity is developmentally regulated and is related to the presence of antigen and not to any specific inhibitor. The immunofluorescence was absent in zoospores but appeared in polarized forms in germinating spores. In elongating hyphae the protease was mainly localized along the cytoplasmic membrane and in the cytoplasm, with predominance at the apex.

Blotting, Western↗

Mitochondrial DNA sequence divergence among some west European brown bear (Ursus arctos L.) populations. Lessons for conservation.

We used the polymerase chain reaction and nucleotide sequencing to study mitochondrial DNA (mtDNA) genetic variability of brown bears (Ursus arctos) belonging to some western European populations. Demographic decline and isolation have apparently shaped genetic variability within and between populations. Small relict bear populations were apparently monomorphic and fixed for different mtDNA haplotypes. Genetic relationships among mtDNA haplotypes suggested the existence of a phylogeographic structure. We discuss the possible roles of historical and demographic factors in determining the observed genetic patterns. The low genetically effective size of the studied brown bear populations points to risks of continuing future loss of gene diversity and increase in inbreeding. Artificial gene flow through restocking could alleviate inbreeding depression in small isolated brown bear populations, and mtDNA phylogeographic relationships may provide a framework for their genetic management.

Animals↗

Day-only admission for varicose vein surgery.

Day-only admissions for surgery are strongly encouraged, in an effort to keep costs down. Varicose vein surgery has been considered too major for day-only management despite the fact that there have been studies from overseas showing that it can be done with a morbidity comparable to inpatient surgery. The morbidity of day-only surgery for varicose veins (both long and short saphenous procedures) was assessed and compared with the results of inpatient surgery. Patients were also asked whether they were satisfied with the surgery being done this way. There were 165 consecutive patients available for study, 64 day-only and 101 inpatient. All patients attending Shellharbour Hospital. Shellharbour, had surgery done as day-only (as it was a morning list and allowed adequate time for recovery). Patients attending Bulli Hospital, Bulli, had surgery done as an inpatient (afternoon list). All surgery was performed by one surgeon. There was no difference (Chi-squared) in the age distribution (mean 48 years for day-only, 51 years for inpatient) or sex proportion in either group (Chi-squared test of proportions with continuity correction). Assessment of the results was done by review of the surgeon's notes, as well as telephone interviews for day-only subjects. The complication rate in both groups was similar. Wound problems represented the main complication with an incidence of 10.5% in each group. There was one deep venous thrombosis (DVT) in each group (diagnosed by duplex scan). Response to the telephone interview suggested that most patients were happy to have the surgery done as a day-only procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

GI nursing: the community health aspect.

Much of the research and literature regarding gastrointestinal nursing addresses concerns of clients in the hospital or outpatient setting. This article focuses on a larger clientele, the well elderly aggregate in the community. Implementation of the nursing process with participants of a local senior center indicated the need for a gastrointestinal education program. A GI health program with a long-range goal of reducing the number of deaths caused by colon cancer was developed and presented. The goal of the program was to educate individuals about colon cancer and the importance of early detection. In this article, the authors describe the application of the nursing process with a well elderly population and the results of that experience for the client and for the GI nurse in the community.

Aged↗

Obturator foramen bypass in the management of infected prosthetic vascular grafts.

The obturator foramen bypass graft remains an excellent option for revascularizing the lower extremity when dealing with an infected prosthetic vascular graft in the groin. In this series, six obturator foramen bypass grafts were performed in five patients for infectious groin complications following vascular surgery. Conservative measures such as local antibiotic irrigation and abscess drainage designed to preserve the graft in situ had failed to eradicate the infection in all instances and was complicated by suture-line haemorrhage in three instances. An aggressive approach should be adopted, aimed at excision of the infected graft. The obturator foramen bypass graft remains a durable graft for limb salvage. Five out of six obturator foramen bypass grafts were patent after 11-26 months follow up.

Abscess↗

Serologic survey for selected viral and rickettsial agents of brown bears (Ursus arctos) in Croatia.

Sera from 22 (13 wild and nine captive) European brown bears (Ursus arctos) from Croatia were tested to 18 viral and rickettsial agents. Serologic evidence of exposure was found to the following agents (number positive/number examined): Bhanja virus (3/15), Tahyna virus (3/15), West Nile virus (4/15), Naples sandfly fever virus (1/15), human adenovirus (1/22), influenza A (1/22) and B (1/22) virus, cytomegalovirus (1/22), parainfluenza virus 1 (2/22), Chlamydia psittaci (1/22), Coxiella burnetii (2/22), and canine parvovirus 2 (CPV-2) (7/22). Evidence of exposure to arboviruses was found exclusively among free-living bears. Evidence of exposure to agents usually transmitted directly was predominant among captive bears. Canine parvovirus 2 antibodies were the most frequently found antibodies and the only antibody common to both groups of bears. This may be the first report of antibodies to CPV-2 in bears.

Animals↗

Serologic survey for leptospirae in European brown bears (Ursus arctos) in Croatia.

From 1981 to 1991, sera of 42 European brown bears (Ursus arctos) from three areas in Croatia were tested for antibodies against 12 Leptospira interrogans serovars: grippotyphosa, sejroe, australis, pomona, canicola, icterohaemorrhagiae, tarassovi, saxkoebing, ballum, bataviae, poi, and hardjo. Diagnostic levels of antibody were found in 17 (40%) of 42 sera. Evidence of exposure to at least one of the serovars was found in seven of 14 free-ranging bears from the Lika region, four of 12 free-ranging bears from the Gorski Kotar region, zero of six orphaned cubs from the Gorski Kotar region, and six of 10 captive bears from the Zagreb Zoo. Based on the antibody titers, we implicated the following serovars: australis in five bears, sejroe in two bears, canicola in one bear, and icterohaemorrhagiae in one bear. There was a strong correlation between serovars implicated by this survey and serovars previously isolated from small mammals in Croatia.

Agglutination Tests↗

Protease inhibitors interfere with the transforming growth factor-beta-dependent but not the transforming growth factor-beta-independent pathway of tumor cell-mediated immunosuppression.

Tumor cells have been reported to exert inhibitory effects on the activation of T lymphocytes in vitro. We show that the IL-2-stimulated proliferation of a Th cell line is suppressed when the T cells are cocultured with human glioblastoma and melanoma cell lines. The use of two Th cell clones that differ in their responsiveness to growth-inhibition by transforming growth factor-beta (TGF-beta) and the analysis of tumor cell-derived supernatants as well as of TGF-beta 1/TGF-beta 2 gene expression allowed to distinguish two pathways of tumor-induced immunosuppression. Glioblastoma cells exert their immunosuppressive effects by producing biologically active TGF-beta 2, whereas the immunosuppressive state induced by melanoma cells is TGF-beta-independent and requires direct contact between tumor cell and T cell. The TGF-beta-dependent immunosuppression is down-regulated by various protease inhibitors and up-regulated by estradiol via modulation of the production of biologically active TGF-beta 2 by glioblastoma cells leaving total activatable TGF-beta 2 unaffected. No such modulation is functional for the TGF-beta-independent pathway of immunosuppression. We conclude that the production of active TGF-beta by tumor cells is regulated at a posttranslational level by the coordinated action of several proteolytic enzymes.

Animals↗

Activation of human platelet-derived latent transforming growth factor-beta 1 by human glioblastoma cells. Comparison with proteolytic and glycosidic enzymes.

Transforming growth factor-beta (TGF-beta), a regulator of cell growth and differentiation, is secreted by most cultured cells in latent form (L-TGF-beta). Activation of L-TGF-beta can be achieved by various physico-chemical treatments, including acidification, alkalinization, heating and chaotropic agents. Proposed physiological activators include proteinases and glycosidases, which, however, only lead to limited activation (15-20% of the total TGF-beta activity after acidic activation). In the present study L-TGF-beta 1 partially purified from human platelets was not activated by treatment with neuraminidase or the proteinases plasmin, endoproteinase Arg-C, elastase and chymotrypsin. The mechanism of activation of L-TGF-beta was further assessed by using the human glioblastoma cell line 308, which releases biologically active TGF-beta 2. Factor(s) secreted by 308 glioblastoma cells were found to be able to activate partially purified L-TGF-beta 1 from human platelets. Our finding may prove to constitute a physiologically relevant mechanism for the activation of latent forms of TGF-beta in vivo.

Blood Platelets↗