[Diagnosis and therapy of leg and pelvic deep vein thrombosis in pregnancy]

OBJECTIVE

To establish differences in the management of acute thrombosis in the deep venous system associated with pregnancy in patients undergoing thrombectomy and in patients receiving heparin therapy.

MATERIALS AND METHODS

From 1984 to 1995 the course of pregnancy was assessed retrospectively in 26 patients with acute deep vein thrombosis. Thirteen patients underwent thrombectomy with establishment of an arteriovenous fistula and 13 patients received conservative treatment with heparin therapy. In addition to the assessment of clinical symptoms, signs of thrombosis, diagnoses established with imaging techniques and of laboratory parameters, early complications and obstetric data obtained in surgically and conservatively treated patients were compared.

RESULTS

The incidence of deep vein thrombosis in the 26 patients (median age 28 years) was 0.21%. In 53.8% of the cases the occurrence of thrombosis was observed in the second trimester (median: 27.5 weeks of gestation). The presence of risk factors was demonstrated in 58% of cases. The most frequently reported symptoms were swelling of the affected leg (88.5%) and pain (61.5%). A marked predilection for the left leg was recorded in 88% of cases. In contrast to phlebography, twice the number of sonographic studies were performed. The comparison of both therapeutic regimes showed a three-fold increase in the rate of early complications in patients after thrombectomy. The rate of recurrent thrombosis in these patients was 58.3% compared to a recurrence rate of 15.4% in patients undergoing heparin therapy.

CONCLUSIONS

Recurrent thrombosis and pulmonary embolism represent the most frequent complications associated with thrombosis in the deep venous system during pregnancy. Although currently there is a lack of conclusive data on the development of postthrombotic syndrome, heparin therapy appears to be associated with fewer maternal risks. Interdisciplinary cooperation is urgently needed.

Selective regulatory effects of purine and pyrimidine nucleotides on vacuolar transport of amino acids

The release of amino acids from their vacuolar store was studied in situ, i.e. in cells with selectively permeabilized plasma membrane and functionally intact vacuoles. As we previously described [Roos et al., J. Biol. Chem. 272 (1997) 15849-15855], this transport process is regulated by extravacuolar adenylates at their physiological concentrations. We now show, using our test object Penicillium cyclopium, that not only purine but also pyrimidine nucleotides are involved in the control of efflux of vacuolar phenylalanine. At 0.1 mM adenosine or guanosine phosphates inhibit, whereas cytidine or uridine phosphates stimulate the rate of efflux. At 1 mM the same nucleotides have no measurable impact on efflux but abolish the effects of other nucleotides present at 0.1 mM. This argues for at least two interacting binding sites with different nucleotide affinities. The minimum structural requirement for any of the observed effects is a non-cyclic ribonucleoside monophosphate. In intact cells, cytosolic concentrations of ATP (representing purine nucleotides) and CTP (representing pyrimidine nucleotides) are 1-2 mM and 0.05-0.2 mM, respectively. ATP is therefore assumed to dominate transport control and allow optimum efflux (and uptake) rates. Short-time starvation of carbon and nitrogen adjusts CTP and ATP at levels that cause declining efflux rates. During prolonged starvation both nucleotides fall below their transport-controlling concentrations and thus allow increasing rates of efflux from the still maintained vacuolar pool. Hence, efflux control under nutrient limitation includes an interplay of purine and pyrimidine nucleotides which precisely regulates the release of vacuolar amino acids and enables flexible adjustment to either amino acid saving or cell survival.

Cloning of the SNG1 gene of Arabidopsis reveals a role for a serine carboxypeptidase-like protein as an acyltransferase in secondary metabolism

Serine carboxypeptidases contain a conserved catalytic triad of serine, histidine, and aspartic acid active-site residues. These enzymes cleave the peptide bond between the penultimate and C-terminal amino acid residues of their protein or peptide substrates. The Arabidopsis Genome Initiative has revealed that the Arabidopsis genome encodes numerous proteins with homology to serine carboxypeptidases. Although many of these proteins may be involved in protein turnover or processing, the role of virtually all of these serine carboxypeptidase-like (SCPL) proteins in plant metabolism is unknown. We previously identified an Arabidopsis mutant, sng1 (sinapoylglucose accumulator 1), that is defective in synthesis of sinapoylmalate, one of the major phenylpropanoid secondary metabolites accumulated by Arabidopsis and some other members of the Brassicaceae. We have cloned the gene that is defective in sng1 and have found that it encodes a SCPL protein. Expression of SNG1 in Escherichia coli demonstrates that it encodes sinapoylglucose:malate sinapoyltransferase, an enzyme that catalyzes a transesterification instead of functioning like a hydrolase, as do the other carboxypeptidases. This finding suggests that SCPL proteins have acquired novel functions in plant metabolism and provides an insight into the evolution of secondary metabolic pathways in plants.

Cloning of the SNG1 gene of Arabidopsis reveals a role for a serine carboxypeptidase-like protein as an acyltransferase in secondary metabolism

Serine carboxypeptidases contain a conserved catalytic triad of serine, histidine, and aspartic acid active-site residues. These enzymes cleave the peptide bond between the penultimate and C-terminal amino acid residues of their protein or peptide substrates. The Arabidopsis Genome Initiative has revealed that the Arabidopsis genome encodes numerous proteins with homology to serine carboxypeptidases. Although many of these proteins may be involved in protein turnover or processing, the role of virtually all of these serine carboxypeptidase-like (SCPL) proteins in plant metabolism is unknown. We previously identified an Arabidopsis mutant, sng1 (sinapoylglucose accumulator 1), that is defective in synthesis of sinapoylmalate, one of the major phenylpropanoid secondary metabolites accumulated by Arabidopsis and some other members of the Brassicaceae. We have cloned the gene that is defective in sng1 and have found that it encodes a SCPL protein. Expression of SNG1 in Escherichia coli demonstrates that it encodes sinapoylglucose:malate sinapoyltransferase, an enzyme that catalyzes a transesterification instead of functioning like a hydrolase, as do the other carboxypeptidases. This finding suggests that SCPL proteins have acquired novel functions in plant metabolism and provides an insight into the evolution of secondary metabolic pathways in plants.

Mycophenolic acid in silage

We examined 233 silage samples and found that molds were present in 206 samples with counts between 1 x 10(3) and 8.9 x 10(7) (mean, 4.7 x 10(6)) CFU/g. Mycophenolic acid, a metabolite of Penicillium roqueforti, was detected by liquid chromatography-mass spectrometry in 74 (32%) of these samples at levels ranging from 20 to 35,000 (mean, 1,400) microg/kg. This compound has well-known immunosuppressive properties, so feeding with contaminated silage may promote the development of infectious diseases in livestock.

Detection of anabolic residues in misplaced implantation sites in cattle

Eight weeks before slaughter, 26 heifers, 2 calves, and 1 steer were implanted with licensed anabolic preparations at off-label injection sites. After slaughter, 24 of 31 implantation sites (77%) were detected. Residual pellets of Revalor H contained a mean of 42.9 mg trenbolone acetate (range 19.8-57.7 mg) and 4.6 mg (1.96-6.45 mg) estradiol, corresponding to 30% (19.8-57.7%) and 32.7% (14.0-46.6%) of the originally applied dose, respectively. In the tissue areas containing residual Revalor H pellets, total residues ranged from 14.8 microg to 12.6 mg trenbolone acetate, 41.7 microg to 1.45 mg trenbolone, and 11.1 microg to 3.39 mg estradiol. The outer tissue areas of the injection sites contained <2 microg hormones. The preparations Synovex H, Finaplix H, Implus S, and Component EC behaved similarly to Revalor H. Residues of Synovex Plus were low, whereas the Compudose silicone rubber contained 58.8% of the implanted dose, but left no significant tissue residues. If implantation sites are processed in meat manufacturing, international threshold levels of the respective substances will be exceeded in tons of meat products.

Ofloxacin causes false-positive immunoassay results for urine opiates

Abstract Immunoassay drug screening tests are usually used as a control during methadone maintenance programmes, to check cleanliness of drugs during detoxification treatment and abstinence programmes. False-positive results can have catastrophic consequences for the patient, as shown in the case report. False-positive results were reported for opioids following ofloxacin or rifampicin and for LSD following mucolytic. Since inpatient and outpatient units usually employ an urine quick test (immunoassay), positive results should be checked with gas chromatography/mass spectroscopy (GC-MS) or high pressure liquid chromatography (HPLC) before conclusions from the positive urine screening results can be drawn.

Cortisol and 17-hydroxyprogesterone levels in saliva of healthy neonates: normative data and relation to body mass index, arterial cord blood ph and time of sampling after birth

The measurement of cortisol and 17-hydroxyprogesterone (17-OHP) in saliva has become a reliable tool for both the scientist and the clinician for studying adrenal cortical function in the adult and the older child. We have now established in parallel normative data for salivary cortisol and 17-OHP levels in healthy neonates. We have asked whether or not there is a circadian rhythm of cortisol and 17-OHP saliva levels in neonates. Furthermore, we have asked whether salivary hormone levels correlated with auxologic and clinical data and time of sampling. Cortisol and 17-OHP levels in saliva samples from 119 healthy neonates (55 girls, 64 boys) were measured using in-house time-resolved fluorescent immunoassays. Saliva samples were obtained using a saliva collecting tube three times a day on the first or second day of life. Gender and gestational age did not influence salivary cortisol and 17-OHP levels. No significant circadian rhythm of salivary hormone levels was detected in this group of newborns. However, body mass index, arterial cord blood pH and time of saliva sampling significantly influenced salivary hormone levels. In conclusion, measurement of cortisol and 17-OHP in saliva is feasible in healthy neonates. The existence of normative data forms the basis for future studies on pathophysiologic states in the newborn period.

Serum androgen levels in adolescents with type 1 diabetes: relationship to pubertal stage and metabolic control

Delayed sexual maturation is still frequently seen in adolescents with type 1 diabetes. A close relationship between insulin and androgen metabolism has been found in a number of studies. Our study was designed to investigate whether or not abnormalities in androgen secretion could play a role in the onset of sexual maturation in adolescents with type 1 diabetes. We have asked whether or not there was a correlation between daily insulin dosage, duration of diabetes, metabolic control, age, pubertal stage, and body mass index (BMI) versus serum androgen concentrations. Basal total and free testosterone, dehydroepiandrosterone-sulfate (DHEA-S), dihydrotestosterone (DHT), sex hormone binding globulin (SHBG) and 3alpha-androstanediol glucuronide (3alpha diol-G) plasma concentrations were measured in 36 pubertal boys and 31 pubertal girls with type 1 diabetes and in 59 sex- and pubertal stage-matched control subjects without diabetes. Significantly higher serum total testosterone (p<0.01) and free testosterone (p<0.05) levels were found in females and males with type 1 diabetes than in controls at pubertal stage 5. DHEA-S, SHBG, DHT and 3alpha diol G concentrations in patients with diabetes were not significantly different from those in controls. There was no correlation between daily insulin requirements and serum androgen levels. These data suggest that adolescents with diabetes have similar serum levels of DHEA-S, SHBG, DHT and 3alpha diol G as healthy subjects at all stages of puberty. However, there are significant differences in serum testosterone and free testosterone levels in adolescents with diabetes when compared to healthy, sex- and pubertal stage-matched controls in late puberty. We hypothesize that the increased testosterone levels in patients with diabetes could relate to reduced fertility in females, disorders of sexual maturation and an increased risk for cardiovascular complications later in life.

Hepatitis C virus core protein promotes immortalization of primary human hepatocytes

Hepatitis C virus (HCV) core protein has many intriguing properties as a viral factor and is implicated in cell growth regulation. In this study, the cell growth regulation potential of HCV core protein was investigated by introduction of the core genomic region into primary human hepatocytes, a natural host for virus replication and tropism. Core-transfected primary human hepatocytes displayed altered cell morphology resembling that of low-differentiated epithelial cells. Those cells retained an immortalized phenotype and exhibited continuous growth after more than 50 passages over 2 years. Stable hepatocyte transfectants exhibited albumin secretion and HCV core protein expression. Telomerase activity, a characteristic of immortalized or transformed cells, was evident in the transfected hepatocytes immediately after senescence. Anchorage-independent growth of the immortalized hepatocytes provided further evidence for a transformed phenotype. Results from these studies suggest that the HCV core protein promotes primary human hepatocytes to an immortalized phenotype, which may predispose cells over an extended period of time to undergo a transforming event. Thus, HCV core protein appears to contribute to virus-mediated pathogenesis in a persistently infected host.

Modified lignin in tobacco and poplar plants over-expressing the Arabidopsis gene encoding ferulate 5-hydroxylase

Ferulate 5-hydroxylase (F5H) is a cytochrome P450-dependent monooxygenase that catalyses the hydroxylation of ferulic acid, coniferaldehyde and coniferyl alcohol in the pathways leading to sinapic acid and syringyl lignin biosynthesis. Earlier studies in Arabidopsis have demonstrated that F5H over-expression increases lignin syringyl monomer content and abolishes the tissue-specificity of its deposition. To determine whether this enzyme has a similar regulatory role in plants that undergo secondary growth, we over-expressed the F5H gene in tobacco and poplar. In tobacco, over-expression of F5H under the control of the cauliflower mosaic virus 35S promoter increased lignin syringyl monomer content in petioles, but had no detectable effect on lignification in stems. By contrast, when the cinnamate 4-hydroxylase (C4H) promoter was used to drive F5H expression, there was a significant increase in stem lignin syringyl monomer content. Yields of thioglycolic acid and Klason lignin in C4H-F5H lines were lower than in the wild-type, suggesting that F5H over-expression leads to a reduced deposition or an altered extractability of lignin in the transgenic plants. Histochemical analysis suggested that the novel lignin in C4H-F5H transgenic lines was altered in its content of hydroxycinnamyl aldehydes. Transgenic poplar trees carrying the C4H-F5H transgene also displayed enhanced lignin syringyl monomer content. Taken together, these data show that hydroxylation of guaiacyl-substituted lignin precursors controls lignin monomer composition in woody plants, and that F5H over-expression is a viable metabolic engineering strategy for modifying lignin biosynthesis in forest species.

A role for leptin in sexual maturation and puberty?

Leptin, the ob gene product, is involved in the regulation of body weight in rodents, primates and humans. It provides a molecular basis for the lipostatic theory of the regulation of energy balance. White adipose tissue and placenta are the main sites of leptin synthesis. There is also evidence of ob gene expression in brown fat. Leptin seems to play a key role in the control of body fat stores by coordinated regulation of feeding behaviour, metabolic rate, autonomic nervous system regulation and body energy balance. Apart from the function of leptin in the central nervous system on the regulation of energy balance, it may well be one of the hormonal factors that signal to the brain the body's readiness for sexual maturation and reproduction. During late pregnancy and at birth when maternal fat stores have been developed, leptin levels are high. During these developmental stages leptin could be a messenger molecule signalling the adequacy of the fat stores for reproduction and maintenance of pregnancy. At later stages of gestation leptin could signal the expansion of fat stores in order to prepare the expectant mother for the energy requirements of full-term gestation, labour and lactation. Leptin serum concentrations change during pubertal development in rodents, primates and humans. In girls, leptin serum concentrations increase dramatically as pubertal development proceeds. The pubertal rise in leptin levels parallels the increase in body fat mass. In contrast, leptin levels increase shortly before and during the early stages of puberty in boys and decline thereafter. Testosterone has been found to suppress leptin synthesis by adipocytes both in vivo and in vitro. The decline of leptin levels in late puberty in boys accompanies increased androgen production during that time and most likely reflects suppression of leptin by testosterone and a decrease in fat mass and relative increase in muscle mass during late puberty in males. This overview focuses on those topics of leptin research which are of particular interest in reproductive and adolescent medicine.

Hepatitis C virus NS5A protein protects against TNF-alpha mediated apoptotic cell death

Hepatitis C virus (HCV) often causes a prolonged and persistent infection which may lead to hepatocellular carcinoma. We have previously reported that the nonstructural 5A (NS5A) protein of HCV promotes cell growth [Ghosh, A.K., Steele, R., Meyer, K., Ray, R., Ray, R.B., 1999. Hepatitis C virus NS5A protein modulates cell cycle regulatory genes and promotes cell growth. J. Gen. Virol. 80, 1179-1183]. In this study, we investigated the role of HCV NS5A (genotype 1a, strain H) in TNF-alpha induced apoptotic cell death. HepG2 cells expressing NS5A exhibited an inhibitory role in relation to TNF-alpha mediated apoptotic cell death. The NS5A protein blocked the activation of caspase-3 and inhibited proteolytic cleavage of the death substrate poly (ADP-ribose) polymerase in TNF-alpha induced cells. Together, these results suggest that HCV NS5A protein protects against TNF-alpha mediated apoptotic cell death.

[Flupenthixol--a partial atypical neuroleptic?]

There is no really clear-cut definition for "atypical" neuroleptics. The most convincing definition is draft by characterization of the receptor-binding profile. Most important are: the combined antagonism of D2 and 5-HT2 receptors, the preferential binding to D4 and D3 receptors and a balanced relation of D2 to D1 antagonism. Flupentixol fits into this description as well as some modern neuroleptics widely considered as "atypical" neuroleptics. Clinical criteria--like the absence of EPMS and the improvement of negative symptoms--offer no clear-cut distinction between "typical" and "atypical" neuroleptics, too, because some modern "atypical" neuroleptics lead--dose-dependent--to EPMS, and there is no proven efficacy for some atypical neuroleptics in the treatment of negative symptoms. So, neuroleptics are labelled "atypical" if there is a favourable relation between antipsychotic activity and the degree of EPMS, and if there is at least some efficacy in the treatment of negative symptoms. In this regard, Flupentixol has to be labelled at least a "partial atypical neuroleptic".

[Hematopoietic stem cells II. Diagnostic and therapeutic aspects]

Characterization and isolation of haematopoietic stem cells (HSC) have resulted in their clinical application in patients with malignant disorders and--through gene therapeutic initiatives--also in the treatment of inherited diseases. Autologous stem cell transplantation (ASCT), which was introduced because of the high number of relapses in cancer patients in remission, involves dose-intensification (conditioning), which induces myeloablation. In this setting, reinfusion of HSC is performed to restore haematopoiesis. Flow cytometric determination of CD34+ cells and clonogenic assays for committed myeloid HSC (CFU-GM) are vehicles for quality control of the harvested HSC material and are integrated into the ASCT programs. Moreover, harvest of HSC and purification of CD34+ cells enables new treatment options such as removal of cancer cells from grafts, optimization of gene transduction as well as ex vivo expansion of HSC before reinfusion. In conclusion, the expanding insights into HSC in the 1990's have already been translated into valuable diagnostic and therapeutic modalities.

Differential ability of heparan sulfate proteoglycans to assemble the fibroblast growth factor receptor complex in situ

Fibroblast growth factors (FGFs) require heparan sulfate proteoglycans (HSPGs) as cofactors for signaling. The heparan sulfate chains (HS) mediate stable high affinity binding of FGFs to their receptor tyrosine kinases (FR) and may specifically regulate FGF activity. A novel in situ binding assay was developed to examine the ability of HSPGs to promote FGF/FR binding using a soluble FR fusion construct (FR1-AP). This fusion protein probe forms a dimer in solution, simulating the dimerization or oligomerization that is thought to occur at the cell surface physiologically. In frozen sections of human skin, FGF-2 binds to keratinocytes and basement membranes of epidermis and dermal blood vessels. In contrast, in skin preincubated with FGF-2, FR1-AP binds avidly to FGF-2 immobilized on keratinocyte cell surfaces, but fails to bind to basement membranes at the dermo-epidermal junction or dermal microvessels despite the fact that these structures bind large amounts of FGF-2. Apparently, basement membrane and cell surface HSPGs differ in their ability to mediate the assembly of a FGF/FR signaling complex presumably due to structural differences of the heparan sulfate chains.

Single photon emission computed tomographic evaluation of brainstem release phenomenon and seizure in neonates

We report the ictal brain single photon emission computed tomographic (SPECT) findings in two neonates. One neonate had hypoxic-ischemic encephalopathy, a disorganized discontinuous electroencephalogram (EEG) background, lethargy, seizures, and brainstem release phenomena. A brain SPECT was performed during a brainstem release phenomenon characterized by a 34-second sustained tonic posture of the right arm and chewing. It did not reveal focal cerebral hemisphere hyperfusion. The second neonate had hemimegalencephaly, low-voltage irregular EEG background, and seizures. A brain SPECT was performed during a seizure characterized by a 32-second sustained tonic posture of the right arm. It revealed focal hyperperfusion in the posterior region of the left hemisphere. The brain SPECT findings in these patients indicate that despite clinically similar events, brainstem release phenomena and seizures have different perfusion characteristics, and refute the theory that brainstem release phenomena are due to epileptic foci in the cerebral hemispheres undetectable by EEG.

Birth kangaroo (skin-to-skin) care and breastfeeding. An eclamptic woman's story

Kangaroo care (KC), also known as skin-to-skin care, has been described often in the nursing literature for its benefits for both preterm and fullterm infants. In this case study KC was used for a mother in a high-risk situation: eclampsia. This mother gave birth to a 34-week preterm infant, and desired breastfeeding. KC was initiated, and due to the high risk for subsequent seizures, included close observation by these nurses. The mother successfully breastfed, and continued the KC at home.

Species differences in induction of hepatic enzymes by BM 17.0744, an activator of peroxisome proliferator-activated receptor alpha (PPARalpha)

BM 17.0744, a new anti-diabetic and lipid-lowering agent, leads also to strong hepatomegaly and carnitine acetyl transferase (CAT) increase in the liver of rats, a phenomenon known from fibrates. For information on the relevance of changes in liver of rats to other species, we investigated the effects of BM 17.0744 on lipids and selected marker enzymes related to beta-oxidation in rats, dogs and guinea-pigs, so-called high and low responders to peroxisome proliferators. To examine selectivity other enzymes were also determined, e.g. esterase, urate oxidase (UOX) and cytochrome c oxidase (CYT.C.OX.). Lowering of triglycerides and cholesterol in blood serum and/or liver was observed in pharmacological dose range in the three species tested. In dogs and guinea-pigs, liver and kidney weights were unaffected even in dogs in medium and high dose groups with high systemic exposure and severe toxicity. In male Sprague-Dawley rats treatment with 1.5, 3, 6 and 12.5 mg/kg per day BM 17.0744 selectively elevated the activities of CAT and acyl-CoA oxidase (AOX) by < or =200 and 20-fold, respectively. Administration of BM 17.0744 to Beagle dogs (1.5, 4, 12 mg/kg per day) and guinea-pigs (3 and 12 mg/kg per day) enhanced the activities of CAT and AOX dose-dependently by a factor of two to three only. Immunoblotting revealed a drug-specific enhancement of the amount of beta-oxidation enzymes in rats, which is in accord with the rapid and coordinated transcriptional activation shown in Northern dot blot analysis. Nuclear run-on assays demonstrated a real transcriptional activation. BM 17.0744 activates peroxisome proliferator-activated receptor alpha (PPARalpha), which could be shown by transactivation assays. The stimulation of PPARalpha by BM 17.0744 was stronger than that of the known ligands WY 14.643 and ETYA. Activation of PPARgamma can be excluded. Taken collectively, the data demonstrate an enhancement of the beta-oxidation system by BM 17.0744 paralleled by lipid-lowering in all species investigated. The activation of the nuclear factor PPARalpha may explain the changes in liver and the metabolic effects on the molecular level. The lack of an increase in liver and kidney weights and the relatively moderate enhancement of activities of beta-oxidation-related enzymes in dogs and guinea-pigs indicate that the excessive response observed in rats is not applicable to other, predominantly non-rodent, species. On the basis of these data and the experience with fibrates a specific risk for humans is not expected.

Detection of melengestrol acetate residues in plasma and edible tissues of heifers

The aim of this study was to gain knowledge of residue formation after the use of melengestrol acetate (MGA) as a growth-promoting agent. Two Holstein-Friesian heifers each received a daily dose through the feed of 0, 0.5 mg (2 heifers with and without withdrawal each), 1.5 mg or 5.0 mg MGA for 8 weeks. MGA residues in plasma were screened by enzyme immuno-assay (EIA). Concentrations in kidney, liver, and muscle were quantified by liquid-chromatography-mass spectrometry (LC-MS), and in fat by gas chromatography-mass spectrometry (GC-MS). MGA levels in plasma were 40, 128, and 280 ng/L, respectively. Residues accumulated in muscle and kidney (5-fold), liver (20-to-40-fold), and fat (200-fold). After administration of 1.5 mg per day the mean MGA concentration in fat was 29 micrograms/kg and thus violated USA regulations which specify a limit of 25 ppb. Therefore the labelled use of MGA (0.5 mg per day) has to be officially controlled.

Left ventricular function during interval and steady state exercise

PURPOSE

Interval training (INT) is a commonly used method of exercise training in both athletic and clinical populations. Although we generally understand left ventricular (LV) function during steady state (SS) exercise, there are no data regarding LV function during INT.

METHODS

We studied eight healthy, physically active volunteers during upright cycle ergometry during 15 min of both SS and INT, at the same average power output (90% individual anaerobic threshold), using first pass radionuclide ventriculography. During INT (60s/60s), measures of LV function were made during work (220 W) after 4 and 12 min and during recovery (120 W) after 7 and 15 min. These were compared with the average of four temporally matched measures made during SS (170 W).

RESULTS

During INT, LV ejection fraction increased from rest (67 +/- 6%) to 77 +/- 5, 80 +/- 5, 77 +/- 5 and 79 +/- 4% after 4, 7, 12, and 15 min, respectively. During SS, LV ejection fraction was not significantly different at rest (70 +/- 4%) or during exercise (76 +/- 4, 79 +/- 4, 80 +/- 3, and 81 +/- 3%) after 4, 7, 12, and 15 min, respectively. Other measures of LV function (HR, BP, LV volumes, cardiac output, systemic vascular resistance, peak emptying, and filling rates) were likewise similar during temporally matched measurements during INT and SS.

CONCLUSIONS

Although there were the expected transitions of ejection fraction with work and recovery, the overall hemodynamic picture during INT was very similar to SS. These data suggest that LV function during INT is not substantially different to that during SS.

Four common mutations of the cystathionine beta-synthase gene detected by multiplex PCR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

BACKGROUND

A deficiency of cystathionine beta-synthase (CBS) is the most frequent cause of homocystinuria. The effect of therapy is related to the underlying CBS genotype, which makes early diagnosis of this genetic defect important. Our aim was to develop a fast and reliable method based on matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for the determination of common mutations of the CBS gene.

METHODS

We used MALDI-TOF mass spectrometry to detect four common CBS mutations (G307S, T272M, I278T, and V320A). The method is based on multiplex PCR of exons 7, 8, and 9, followed by single nucleotide extension in the presence of dideoxy NTPs of four primers targeted at the separate mutation sites. The extension products, as well as the 3-hydroxypicolinic acid matrix, were incubated with cation-exchange beads to remove disturbing salt contaminants.

RESULTS

The above-mentioned mutations were determined in samples from 12 homocystinuria patients. The MALDI-TOF spectra allowed unambiguous discrimination between primers and extension products (>9 Da) in the mass range between 4500 and 7500 Da. No labeled primers or ddNTPs were required. The genotyping was verified by reference technique.

CONCLUSION

Our results demonstrate fast, simple, and unambiguous multiplex genotyping of four common CBS mutations by MALDI-TOF mass spectrometry.

Using kangaroo care in a clinical setting with fullterm infants having breastfeeding difficulties

Usually Kangaroo Care (KC) or skin-to-skin holding care is done with preterm infants. This article, however, documents clinical experiences with three mothers and their fullterm infants who were having latching/breastfeeding difficulties. In each case the nurse placed the fullterm infant in KC for approximately 1 hour prior to and continuing into the next breastfeeding session. Although no recommendations can be made based on case studies, these clinical experiences suggest that KC is a worthwhile intervention to try when a mother and her fullterm infant are struggling to achieve successful breastfeeding.

Interaction of eukaryotic initiation factor eIF4B with the internal ribosome entry site of foot-and-mouth disease virus is independent of the polypyrimidine tract-binding protein

Eukaryotic translation initiation factor 4B (eIF4B) binds directly to the internal ribosome entry site (IRES) of foot-and-mouth disease virus (FMDV). Mutations in all three subdomains of the IRES stem-loop 4 reduce binding of eIF4B and translation efficiency in parallel, indicating that eIF4B is functionally involved in FMDV translation initiation. In reticulocyte lysate devoid of polypyrimidine tract-binding protein (PTB), eIF4B still bound well to the wild-type IRES, even after removal of the major PTB-binding site. In conclusion, the interaction of eIF4B with the FMDV IRES is essential for IRES function but independent of PTB.