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A Brand

Publications and source records attributed to A Brand.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Comparative presentation of current economic evaluation studies for phenylketonuria screening].

A systematic review was undertaken to assess the economic value of PKU screening in the framework of newborn screening for inborn errors of metabolism. Therefore, seven international studies on this topic were connected and examined with regard to differences and similarities. The relation between costs and benefits of PKU-screening programmes goes from 1:1,2 up to 1:9,25. The differences can be explained by varying incidence of PKU (in international comparison) and particularly by methodical differences in the respective study designs. This aspect is pointed out while taking up and emphasising the necessity of standardisation in economic evaluation studies. Furthermore, future developments (chances, trends, changes) in newborn screening are discussed, based on the potential use of new technologies.

Cost-Benefit Analysis↗
PubMed1998

A Cox proportional-hazards model with time-dependent covariates to evaluate the relationship between body-condition score and the risks of first insemination and pregnancy in a high-producing dairy herd.

The objective of this study was to determine the relationship between body-condition score and postpartum reproductive efficiency in dairy cattle. Data on body-condition score, reproduction, diseases, and production from 1404 lactations of 639 cows, calving between January 1984 and November 1996 on a commercial farm, were used. The Cox proportional-hazards model with time-dependent covariates was used to qualify the relationship between body-condition score on a scale of 1 to 5 and risks of first insemination and pregnancy. Cows with body condition at calving < 3 had lower first-insemination risks. Loss of body-condition score between calving and 45 days after calving was associated with increased days open and days-to-first insemination. Cows with body-condition scores < 2 after Day 45 and before first insemination were less likely to be inseminated and become pregnant compared with cows that had higher body condition. Milk yield, mastitis, lameness, milk fever and genital infection were associated with a reduction in reproductive efficiency. The results indicated that loss of body-condition and actual body-condition scores before conception or first insemination or both can be used as a prognosis for days open and days-to-first insemination in dairy herds.

Animals↗
PubMed1998

[Paroxysmal nocturnal hemoglobinuria in pregnancy].

The combination of paroxysmal nocturnal haemoglobinuria (PNH) and pregnancy occurred in three women aged 29, 31 and 35 years. One patient had a spontaneous abortion twice after which she committed suicide. In the other two the pregnancy and parturition--assisted--were without complications. However, one woman developed post-partum abdominal crises. The children were born at term and healthy. PNH is a rare form of haemolytic anemia. Pregnancy causes lethal complications in 6% of the cases of PNH, while 30% of the pregnancies end in spontaneous abortion or stillbirth. Accurate monitoring of pregnancy and the puerperium is essential.

Abortion, Spontaneous↗
PubMed1998

Direct administration and utilization of [1-13C]glucose by fetal brain and liver tissues under normal and ischemic conditions: 1H, 31P, and 13C NMR studies.

Three distinct, maternal-independent routes (e.g. intraamniotic, intraperitoneal and intracerebral), for [1-13C]glucose utilization by fetal brain and liver tissues, were examined by multinuclear magnetic resonance (NMR) spectroscopy before and after vascular occlusion of the maternal-fetal blood flow. Labeled lactate was the major glycolytic product by all routes, but in addition labeled TCA cycle products were also generated. Fractional 13C enrichment in both glucose and lactate were always higher in the ischemic state compared to controls using either one of the three routes studied. After intraperitoneal injection total glucose in the fetal brain was decreased by 85% after 20 min reperfusion following 20 min ischemia, but was elevated up to 170% after 60 min. [1-13C]glucose increased continuously by up to 370% after 60 min. Total glucose in the fetal liver remained unchanged while [1-13C]glucose increased up to 380%. Total lactate level in brain was 50-80% above the control apart from a transient increase (140%) notable after 40 min reperfusion. The kinetics of [3-13C]lactate followed a similar time course. At the same time when lactate was transiently increased in fetal brain, total lactate as well as 13C-labeled lactate showed a transient decrease in liver after 40 min. While the ways of mobilization of energy substrates for maintaining adequate metabolic activity in the fetal brain remain still unclear, the present 13C NMR studies suggest that both liver glucose and lactate can contribute to brain metabolism particularly under ischemic stress.

Adenosine Triphosphate↗
PubMed1998

[Subspecialty blood transfusion medicine].

The unification of Europe, the related principle of self-sufficiency and the prevention of blood banks turning into bureaucratic institutes that lose connection with bedside medicine underscores the need for training in transfusion medicine and its international organization. In most European countries transfusion medicine is now recognized as a specialty in its own right. In the Netherlands it was decided to recognize transfusion medicine as subspecialty of Internal Medicine. This new initiative led to a training programme of 6 years in all, of which the last 18 months are devoted to transfusion medicine exclusively. The importance of continuous education and practice in both fields is recognized.

Blood Banks↗
PubMed1998

Flow cytometric measurement of neutrophil alkaline phosphatase before and during initiation of an induced Escherichia coli mastitis in cattle.

In 12 healthy cows, neutrophil alkaline phosphatase (NAP) activity was measured by flow cytometer before and during an experimentally induced Escherichia coli mastitis, to study the role and increase of NAP in Gram-negative bacterial infections. Percentage of neutrophils containing alkaline phosphatase and intensity of NAP activity were measured. Preinfection percentage of neutrophils with enzyme activity varied between 64.0% and 84.4% and the intensity of enzyme activity was low in all cows. After induction of infection, percentage of neutrophils with enzyme activity showed a significant decrease on day 1 followed by an significant increase on day 3. NAP intensity increased significantly on the second and third day after infection. This increase of intensity was significantly, positively correlated with the severity of infection. From this study we may conclude that variation in susceptibility to E. coli mastitis could not be explained by preinfection NAP levels. The post-infection increase of NAP activity, that was found following an induced infection was more a result of increased enzyme intensity per neutrophil, then from an increase of percentage neutrophils with enzyme activity. Furthermore, a strong correlation was found between NAP intensity and severity of inflammation. There was evidence that the more severely diseased animals showed stronger NAP intensity increase.

Alkaline Phosphatase↗
PubMed1998

Beneficial effects of leukocyte depletion of transfused blood on postoperative complications in patients undergoing cardiac surgery: a randomized clinical trial.

BACKGROUND: Leukocytes in transfused blood are associated with several posttransfusion immunomodulatory effects. Although leukocytes play an important role in reperfusion injury, the contribution of leukocytes in transfused blood products has not been investigated. To estimate the role and the timing of leukocyte filtration of red cells in cardiac surgery, we performed a randomized study. METHODS AND RESULTS: Patients scheduled for cardiac surgery were randomly allocated to receive either packed cells without buffy coat (PC, n = 306), fresh-filtered units (FF, n = 305), or stored-filtered units (SF, n = 303) when transfusion was indicated. We evaluated the periods of hospitalization and stay at the intensive care unit, and the occurrences of postoperative complications up to 60 days after surgery. The average hospital stay was 10.7 days, of which 3.2 days were in the intensive care unit, without significant differences between the groups. In the PC trial arm, 23.0% of the patients had infections versus 16.9% and 17.9% of the patients in the leukocyte-depleted trial arms (P=.13). Within 60 days, 45 patients had died, 24 patients in the PC trial arm (7.8%), versus 11 (3.6%) and 10 (3.3%) patients in the FF and SF trial arms, respectively (P=.015). CONCLUSIONS: In cardiac surgery patients, especially when more than three blood transfusions are required, leukocyte depletion by filtration results in a significant reduction of the postoperative mortality that can only partially be explained by the higher incidence of postoperative infections in the PC group.

Aged↗
PubMed1998

Rat brain primary neurons immobilized in basement membrane gel threads: an improved method for on-line 13C NMR spectroscopy of live cells.

In vivo MRS studies on intact brain reflect the metabolism of all cells present, but do not distinguish between different cell types. NMR studies of immobilized cultured primary cells, such as neurons and astrocytes, are a useful model to monitor the specific differences in metabolism of the various cell types in the brain. The present study shows that primary rat neuronal cells can be cultured in basement membrane gel threads. After 4 days of incubation the threads are filled with viable cells, and represent a population of morphologically differentiated neuronal cells with less than 5% of non-neuronal cells, i.e., astrocytes. These threads were placed into a NMR tube and used for on-line monitoring of neuronal metabolism. Under these conditions cells remained viable and metabolically active for several days. The energy status was monitored by using 31P NMR spectroscopy. To study neuronal glucose metabolism [1-13C]glucose was added to the perfusion medium and 30 min later 13C-labeled metabolites were detectable by 13C NMR spectroscopy. Immobilized neurons synthesized glycolytic products such as [3-13C]lactate and [3-13C]alanine, as well as several tricarboxylic acid cycle products, i.e., [2-13C]glutamate, [3-13C]glutamate, [4-13C]glutamate, [2-13C]aspartate, and [3-13C]aspartate. In summary, 31P and 13C NMR spectra can be recorded from live neuronal cells for up to 24 h using the newly designed procedure described in the present communication.

Animals↗
PubMed1998

Effects of thrombopoietin on the proliferation and differentiation of primitive and mature haemopoietic progenitor cells in cord blood.

Thrombopoietin (TPO) is considered to be the primary growth factor for regulating megakaryopoiesis and thrombopoiesis. In this study we investigated the in vitro effect of TPO on relatively immature and mature CD34+ progenitor cells in cord blood. Cells were cultured in both liquid and semi-solid cultures containing 50 ng/ml TPO. The CD34+/CD45RA- and CD34+/CD38- subfractions in cord blood were both enriched for megakaryocyte progenitors as determined in a semisolid CFU-meg assay. Progenitor cells derived from the CD34+/CD45RA- and CD34+/CD38- subfractions showed high proliferative capacity in liquid cultures. We observed a mean 19-fold expansion of the total CD34+ cell fraction, whereas in the CD34+/CD45RA- and CD34+/CD38- subfractions the mean expansion was 23- and 50-fold respectively. The expansion of the immature progenitor cell subfractions resulted in a highly purified megakaryocyte suspension containing > 80% megakaryocytes after 14 d in culture. However, these expanded megakaryocytes remained in a diploid (2N) and tetraploid (4N) state. Maturation could not be further induced by low concentration of TPO (0.1 ng/ml). The majority of the cells were 2N (80%) and 4N (15%) and only 5% of the cells had a ploidy of more than 4N. These results indicate that megakaryocyte progenitor cells in cord blood residing in the immature stem cell fraction exhibit a high proliferative capacity when cultured in the presence of TPO as the single growth factor, without maturation to hyperploid megakaryocytes.

ADP-ribosyl Cyclase↗
PubMed1998

Pregnancy and severe aplastic anaemia: causal relation or coincidence? .

The relationship between aplastic anaemia (AA) and pregnancy remains uncertain. To assess whether an association between pregnancy and severe aplastic anaemia (SAA) exists, we compared the frequency of pregnancy in 35 young women with newly diagnosed SAA with the expected frequency in the general population. The observed pregnancy rate in the SAA group was 3-6%. This percentage approximates the expected pregnancy rate of 4.4% in the general population and is not compatible with a strong association between pregnancy and SAA.

Adolescent↗
PubMed1998

Metabolism of glycine in primary astroglial cells: synthesis of creatine, serine, and glutathione.

The metabolism of [2-13C]glycine in astroglia-rich primary cultures obtained from brains of neonatal Wistar rats was investigated using 13C NMR spectroscopy. After a 24-h incubation of the cells in a medium containing glucose, glutamate, cysteine, and [2-13C]glycine, cell extracts and incubation media were analyzed for 13C-labeled compounds. Labeled creatine, serine, and glutathione were identified in the cell extracts. If arginine and methionine were present during the incubation with [2-13C]glycine, the amount of de novo synthesized [2-13C]creatine was two-fold increased, and in addition, 13C-labeled guanidinoacetate was found in cell extracts and in the media after 24 h of incubation. A major part of the [2-13C]glycine was utilized for the synthesis of glutathione in astroglial cells. 13C-labeled glutathione was found in the cell extracts as well as in the incubation medium. The presence of newly synthesized [2-13C] serine, [3-13C]serine, and [2,3-13C]serine in the cell extracts and the incubation medium proves the capability of astroglial cells to synthesize serine out of glycine and to release serine. Therefore, astroglial cells are able to utilize glycine as a precursor for the synthesis of creatine and serine. This proves that at least one cell type of the brain is able to synthesize creatine. In addition, guanidinoacetate, the intermediate of creatine synthesis, is released by astrocytes and may be used for creatine synthesis by other cells, i.e., neurons.

Animals↗
PubMed1998

Metabolism of cysteine in astroglial cells: synthesis of hypotaurine and taurine.

The synthesis of hypotaurine and taurine was investigated in astroglia-rich primary cultures obtained from brains of neonatal Wistar rats using 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Cell extracts of astroglial cultures analyzed by 1H NMR spectroscopy show prominent signals of hypotaurine. To identify cysteine as precursor for hypotaurine and taurine synthesis in astroglial cells, primary cultures were incubated with [3-(13)C]cysteine for 24 or 72 h. Cell extracts and incubation media were then analyzed with 13C NMR spectroscopy. Labeled hypotaurine, taurine, glutathione, and lactate were identified in the cell extracts. Within 72 h, 35.0% of the total intracellular hypotaurine and 22.5% of taurine were newly synthesized from [3-(13)C] cysteine. The presence of [1-(13)C]hypotaurine and [1-(13)C]taurine in the incubation medium proves the release of those products of cysteine metabolism into the medium. Minor amounts of the [3-(13)C]cysteine were used for the synthesis of glutathione in astroglial cells or metabolized to [3-(13)C]lactate, which was found in cell extracts and media. These results indicate that the formation of hypotaurine and taurine is a major pathway of cysteine metabolism in astroglial cells.

Animals↗
PubMed1998

Profiles of patients with left prefrontal and left temporal lobe lesions after cerebrovascular infarcations on California Verbal Learning Test-like indices.

We compared memory disorders of three patient groups suffering from brain lesions with a word list corresponding to the California Verbal Learning Test (CVLTgcor). Dependent measures were learning rate and efficiency, retention, and strategic control of the learning process. Compared to a control group of patients with right hemispheric lesions, a left Arteria cerebri posterior (LACP) group showed general memory deficits, an inflated recency effect, and increased serial clustering. A left prefrontal cortex (LPFC) group documented slowed learning and increased recall after semantic cues. Discriminant analysis correctly classified 86.11% of the patients. It is argued that (a) the CVLT helps to cover differences in memory disorders recently discussed in cognitive neuropsychology; (b) differences between PFC and ACP patients become evident only if strategic aspects of learning and increased recall after semantic cueing are taken into account. The results are discussed within the framework of recent cognitive neuropsychological findings and with a distinction between fronto-subcortical and cortical memory disorders.

Attention↗
PubMed1998

Intravenous immunoglobulin treatment in hematological diseases.

In the last decade large amounts of intravenous immunoglobulin (i.v.Ig) have been used worldwide. Doubts exist as to whether this increased use is paralleled by a comparable growth of reliable data on the therapeutic effectiveness of i.v.Ig. We performed a literature search using MEDLINE from January 1981 to January 1997 and analysed articles on the use of i.v.Ig in hematological disorders and searched for published guidelines. For most hematological disorders, evidence to use i.v.Ig as first line therapy is not very strong. For many disorders no controlled trials have been performed. In published guidelines, i.v.Ig is only recommended, with a few exceptions, when other treatments have failed or are contraindicated. Therefore the increase of consumption of i.v.Ig can not be explained by an increase in established indications in hematology.

Clinical Trials as Topic↗
PubMed1998

Multinuclear NMR spectroscopy studies on NH4Cl-induced metabolic alterations and detoxification processes in primary astrocytes and glioma cells.

Glutamine synthesis, the major pathway of ammonia detoxification, and the intracellular concentration of organic osmolytes in primary astrocytes and F98 glioma cells were investigated with multinuclear magnetic resonance spectroscopy. Acute exposure to ammonia (3 h incubation with NH4Cl) raised the concentration of glutamine and other amino acids, such as glutamate and aspartate, and decreased myo-inositol, hypotaurine, and taurine concentrations. The loss of these osmolytes was partially reversed by co-treatment with the glutamine synthetase inhibitor, methionine sulphoximine. Glutamate, the precursor of glutamine, is provided by stimulated anaplerotic flux via pyruvate carboxylase and glutamate dehydrogenase activity. Thus, the glutamine increase and myo-inositol decrease observed by in vivo magnetic resonance spectroscopy on patients with hepatic encephalopathy may be due to the disturbed osmoregulation in astrocytes caused by accumulation of glutamine and the subsequent loss of organic osmolytes.

Amino Acids↗
PubMed1998

Incidence of clinical mastitis in dairy herds grouped in three categories by bulk milk somatic cell counts.

Incidence of clinical mastitis was studied in 274 herds grouped in three categories by bulk milk somatic cell count (SCC). Mean incidence rate of clinical mastitis was 0.278, 0.257, and 0.252 cases per 365 cow-days at risk in herds with low (< or = 150,000), medium (150,000 to 250,000), and high (250,000 to 400,000 cells/ml) bulk milk SCC, respectively. The incidence rate of clinical mastitis was not different among the three categories. Variance in the incidence of clinical mastitis among herds increased as bulk milk SCC decreased. Clinical mastitis caused by Gram-negative pathogens, such as Escherichia coli, Klebsiella spp., or Pseudomonas spp., occurred more often in herds with a low bulk milk SCC. Clinical mastitis caused by Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus agalactiae occurred more often in herds with a high bulk milk SCC. Systemic signs of illness caused by clinical mastitis occurred more often in herds with a low bulk milk SCC. Both overall culling rate and culling rate for clinical mastitis were not different among groups catergorized by bulk milk SCC. In herds with a high bulk milk SCC, however, more cows that produced milk with a high SCC were culled. In herds with a low bulk milk SCC, more cows were culled for teat lesions, milkability, udder shape, fertility, and character than were cows in herds with a high bulk milk SCC. In herds with a low bulk milk SCC, cows were also culled more for export and production reasons.

Animals↗