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Biomedical subjects

H Andersen

Publications and source records attributed to H Andersen.

At least 55 records · Page 3Linked to original sources
PubMed1996

Reliability of isokinetic measurements of ankle dorsal and plantar flexors in normal subjects and in patients with peripheral neuropathy.

OBJECTIVE: To establish a reliable method for evaluation of motor performance of ankle dorsal and plantar flexors in healthy subjects and in patients with peripheral neuropathy. DESIGN: Thirty-eight control subjects and 7 patients with peripheral neuropathy were studied. All patients and 25 control subjects were test twice. PATIENTS AND CONTROL SUBJECTS: An outdoor clinic sample of 7 patients with hereditary motor sensory neuropathy (HMSN) and 38 control subjects. MAIN OUTCOME MEASURES: The effect of a rest interval, a displacement of the axis of rotation, examination by three investigators on the peak torque and work of dorsal and plantar flexors, and the percentage difference at test-retests. RESULTS: Control subjects had percentage differences of 5.6% and 8.0% for dorsal flexion and 3.8% and 8.7% for plantar flexion at 60 degrees/sec and 180 degrees/sec, respectively. In neuropathic patients the percentage differences were 0% and 8.6% for dorsal and 5.1% and 12.3% for plantar flexion at 30 degrees/sec and 60 degrees/sec, respectively. No interindividual differences between 3 investigators were found. A rest interval between trials resulted in an increased plantar flexion peak torque (P < .05). Displacement of 1.5cm of the axis of rotation resulted in a change of the peak torque of 8.3% for plantar flexion (P < .01). CONCLUSIONS: A well-defined test protocol for isokinetic motor performance of the ankle dorsal and plantar flexors provides a reliable procedure for quantification of motor function in healthy subjects and in patients with HMSN1.

Adult↗
PubMed1996

Prostaglandin E2 inhibits antidiuretic hormone induced transepithelial sodium transport and cAMP production in frog skin epithelium (Rana esculenta).

The stimulation of transepithelial sodium transport by arginine vasotocin (AVT) and the ability of prostaglandin E2 (PGE2) to inhibit the AVT dependent sodium transport was examined on pieces of frog skin taken from different regions of the frog. The basal sodium transport was of the same magnitude in the abdominal, thoracal and upper and lower dorsal region. In all regions the sodium transport could be stimulated by AVT, though the stimulation was highest in the abdomen. Subsequent addition of PGE2 caused a significant inhibition of the AVT dependent sodium transport in the abdomen but had only minor effects on the other parts of the skin. Therefore, pieces of skin from the abdomen were selected for the remaining experiments. Addition of PGE2 to skin pieces in the presence of AVT resulted in a hyperpolarization of the cellular potential and a decrease in the transepithelial sodium transport, indicating a decreased apical sodium permeability. This was correlated with a decrease in cellular cAMP contents. We conclude that frog skin exhibits large regional differences in sensitivity to AVT and that PGE2 only modulates the natriferic effect of AVT in the abdomen.

Animals↗
PubMed1996

Isokinetic muscle strength in long-term IDDM patients in relation to diabetic complications.

The isokinetic muscle strength in 56 IDDM patients with > 20 years of diabetes duration and in their individually sex-, age-, weight-, and height-matched control subjects was assessed. Peak torque of foot dorsal and plantar flexion and knee and wrist extension and flexion was measured. The neuropathic condition was assessed by a neurological disability score, a neuropathy symptom score, nerve conduction studies, and quantitative sensory examination. All results were summed to obtain a neuropathy rank-sum score for each patient. According to their renal albumin excretion, the patients were classified to have normo-, micro-, or macroalbuminuria. In addition, according to their retinal status, patients were classified as having no, simple, or proliferative retinopathy. The IDDM patients had a 21% reduction of muscle strength of both ankle dorsal (P < 1 x 10(-4)) and plantar flexors (P < 0.01), compared with control subjects. A 16% reduction of knee extensors (P < 0.005) and a 17% reduction of knee flexors (P < 0.01) was found. In contrast, muscle strength in wrist flexors and extensors was not significantly reduced (10 and 11%, respectively [NS]). In patients with the most severe weakness, muscle strength of the calf muscles was only 50% of the expected performance. Correlations were found between the neuropathy rank-sum score and the muscle strength of ankle dorsal (r = -0.66, P < 1 x 10(-7)) and plantar flexors (r = -0.51, P < 0.0005), knee extensors (r = -0.51, P < 0.0005) and flexors (r = -0.44, P < 0.005), and wrist flexors (r = -0.41, P < 0.005). No correlation was found for wrist extensors (r = 0). Neither were there any relationships between muscle strength at the ankle and knee and the degree of albuminuria or retinopathy. In conclusion, motor performance is substantially impaired in long-term IDDM patients, and the weakness is related to the presence of neuropathy but not to albuminuria or retinopathy per se.

Adult↗
PubMed1995

[Fatal cases of poisonings among drug addicts in the county of Funen in 1993].

This study includes death from poisoning among drug addicts in 1993 in the county of Funen, in all 24. The development during the last five years shows an increase, especially in the largest city in the county. The drug addicts have several problems, and several of them were well-known in the social welfare system or by the police. Half of the drug addicts had received treatment for their abuse and three persons were receiving treatment at the time of their death. A few--primarily among the youngest--had only used drugs for a short time while one third had abused drugs for several years. The greater part of the deaths were caused by heroin, which is found in different concentrations in the illegal market. Five of the dead persons had just been released from prison and three people had just left 24-hour care centres when they were found dead. Co-operation between the various, treating authorities has to be given a high priority.

Adolescent↗
PubMed1995

Motor pathway function in normoalbuminuric IDDM patients.

Central motor pathways were studied in 17 normoalbuminuric insulin-dependent diabetic (IDDM) patients who had been diabetic for more than 20 years, and compared with findings in 17 age-, sex-, and height-matched control subjects. The central motor conduction time was calculated from recordings of the compound muscle action potentials of the abductor pollicis brevis muscle after single transcranial and spinal root magnetic stimulation. The central motor conduction time from motor cortex to cervical spinal roots was 9.8 +/- 1.65 ms in diabetic patients and 10.1 +/- 1.48 ms in control subjects. In diabetic patients with neuropathy the central motor conduction time was 9.5 +/- 1.76 ms vs 10.1 +/- 1.56 ms in patients without neuropathy. The excitability of the motor pathways was studied by paired transcranial magnetic stimulation at interstimulation intervals of 30-1000 ms. In normal control subjects, an early facilitation of the amplitude of the compound muscle action potential at an interstimulation interval of 30 ms was found, while no facilitation was present in diabetic patients. In addition the compound muscle action potential latencies were prolonged at interstimulation intervals of 30-50 ms in diabetic patients. The changes of excitability did not correlate with the presence of peripheral neuropathy, metabolic control or diabetes duration. It is concluded that long-term normoalbuminuric IDDM patients have imparied excitability but normal central conduction time of the motor pathways.

Adult↗
PubMed1994

Bovine histidine-rich glycoprotein is a substrate for bovine plasma factor XIIIa.

Histidine-rich glycoprotein was purified from bovine plasma and the identity of the protein confirmed through amino acid sequencing. Activated bovine factor XIIIa catalyzed the incorporation of 1 nmol of 1,4-[14C]putrescine into 1 nmol of bovine histidine-rich glycoprotein, showing that histidine-rich glycoprotein has the ability to participate in transglutaminase-catalyzed reactions in vivo.

Amino Acid Sequence↗
PubMed1994

Inability of insulin to maintain normal nerve function during high-frequency stimulation in diabetic rat tail nerves.

The effect of insulin on the response to long-term high-frequency stimulation (HFS = 143 Hz for 20 min) was studied in mixed tail nerves of acute streptozotocin-induced diabetic rats. In consecutive tests, untreated diabetic rats showed a significant decrease in nerve conduction velocity (NCV) and peak-to-peak amplitude (P-Pamp) and the depression of the P-Pamp during HFS was augmented. In contrast, NCV and P-Pamp in the insulin-treated rats were unchanged from the prediabetic state, but the depression of the P-Pamp during HFS reached the same degree as in untreated rats. This implies that although insulin treatment of acute experimental diabetes is able to preserve a normal NCV and P-Pamp in the resting state, it is unable to preserve normal nerve function under stress produced by HFS. Monitoring of the axon membrane functional capacity may have clinical implications in the control of peripheral neuropathies.

Action Potentials↗
PubMed1994

Long term impact of high titer Edmonston-Zagreb measles vaccine on T lymphocyte subsets.

Several trials of high titer measles vaccine (> 10(4.7) plaque-forming unit) have found female recipients of Edmonston-Zagreb (EZ) vaccine to have lower survival than female recipients of standard measles vaccine. Two trials with medium and high titer EZ vaccine from the age of 4 months were conducted in Guinea-Bissau. To test for possible long term impact on the immune system, an investigation of T cell subsets was conducted among all children still residing in the community at 3 to 5 years of age. No differences were found between recipients of medium titer vaccine and controls. In the second trial, however, recipients of high titer had lower CD4:CD8 ratios than controls and had significantly higher CD8 percentages and lower CD4:CD8 ratios than recipients of medium titer EZ. When analyzed by sex, differences were found only among the girls. However, these differences were small and seemed unlikely to explain the reduced survival which has been associated with high titer EZ measles vaccination. In the 2 years after the investigation of T cell subsets, there was no increased mortality for recipients of EZ vaccine. Hence it is unlikely that high titer vaccine has an persistent adverse effect on survival after 3 years of age.

CD4-CD8 Ratio↗
PubMed1993

Reduced capability of transmitting high frequency impulses in tail nerves of diabetic rats.

The effect of long-term (40 min) high frequency stimulation (143 Hz) of sensory-motor tail nerves was studied in normal and in streptozotocin-diabetic rats. The study comprised a 6-week period, repeating the test at 2-week intervals. In the initial (prediabetic) study, single experiments showed a mild depression of the peak-to-peak amplitude during high frequency stimulation, which reversed completely during a subsequent rest period. In normal rats, the amplitude depression was unchanged in repeated tests over a 6-week period. Diabetic rats showed a greater amplitude depression during high frequency stimulation. The difference was statistically significant after 2 weeks, but showed no further change at subsequent tests. The greater decrease in the amplitude in diabetic rats may reflect a depression of the axon membrane function, which may be the functional correlate to the inhibition of the Na/K ATPase activity in diabetes, described by others. Monitoring of the axon membrane functional capacity may have clinical implications in the control of peripheral neuropathies.

Action Potentials↗
PubMed1992

Papaverine reduces the sodium permeability of the apical membrane and the potassium permeability of the basolateral membrane in isolated frog skin.

The effect of papaverine, an inhibitor of the phosphodiesterase responsible for breakdown of cAMP, on the transepithelial sodium transport across the isolated frog skin was investigated. Serosal addition of papaverine caused initially an increase in the short-circuit current (SCC), a doubling of the cellular cAMP content and a depolarization of the intracellular potential under SCC conditions (Vscc). The initial increase in the SCC was followed by a pronounced decrease both in the SCC and in the natriferic action of antidiuretic hormone (ADH), but papaverine had no inhibitory effect on the ability of ADH to increase the cellular cAMP content. As SCC declines, no hyperpolarization was observed. The I/V relationship across the apical membrane during the inhibitory phase, revealed that papaverine reduces the sodium permeability of the apical membrane (PNaa) as well as intracellular sodium concentration. These observations and the previously noted effect of papaverine on Vscc indicates that papaverine must have an effect on the cellular Cl or K permeability. The basolateral Na,K,2Cl cotransporter was blocked with bumetanide, which should bring the cellular chloride in equilibrium. Bumetanide had no effect on basal SCC and Vscc. When papaverine was added to skins preincubated with bumetanide, the effect of papaverine on SCC and Vscc was unchanged. Therefore, the depolarization of Vscc, observed during the papaverine-induced inhibition of the SCC, must be due to a reduction in the cellular K permeability. In conclusion, it is suggested that papaverine reduces the sodium permeability of the apical membrane and the potassium permeability of the basolateral membrane of the frog skin epithelium.

Animals↗
PubMed1992

Increased yield of myeloid progenitor cells in bone marrow harvested for autologous transplantation by pretreatment with recombinant human granulocyte-colony stimulating factor.

Pretreatment with haemopoietic cytokines prior to marrow harvest may result in improved quality of bone marrow harvested for autologous bone marrow transplantation (BMT). Such improvements may reduce the risk for graft failure and decrease time to engraftment. Patients undergoing autologous BMT received recombinant human G-CSF (rhG-CSF) immediately prior to marrow harvest. rhG-CSF was administered as daily subcutaneous injections for 5 days at 5 micrograms/kg body weight. Comparison of bone marrow samples before and after rhG-CSF treatment showed an increased bone marrow cellularity and a ninefold increase in the number of marrow leucocytes per volume aspirated. The mean marrow myeloid:erythroid ratio increased from 2.6 to 4.0. The mean numbers of immature (CD38 positive) and proliferating (CD71 positive) myeloid cells increased significantly from 41.6 to 50.8% and from 17.0 to 34.8%, respectively. Other subsets studied, including CD34 positive stem cells, were unchanged. The relative numbers of day 7 and 14 granulocyte-macrophage colony-forming units (day 7/14 GM-CFU) were unchanged. Long-term marrow cultures revealed that the numbers of 'long-term culture initiating cells' were unchanged after rhG-CSF treatment in spite of the ninefold increase in cellularity. To date, five of the patients have been transplanted with autologous marrow harvested after rhG-CSF treatment. Time to trilineage engraftment was unchanged compared with historical controls. We conclude that pretreatment with rhG-CSF prior to marrow harvest may improve the graft by increasing the total number of myeloid lineage restricted progenitor cells, resulting in stable but not accelerated myeloid engraftment of autologous marrow.

Bone Marrow Transplantation↗
PubMed1990

Effect of 12-O-tetradecanoyl phorbol 13-acetate on solute transport and production of cAMP in isolated frog skin.

In the present study we have examined the action of the phorbol diester tetradecanoyl phorbol acetate, an activator of protein kinase C, on the transepithelial transport of sodium, chloride and water and the production of cAMP in the isolated frog skin epithelium (Rana esculenta). Addition of tetradecanoyl phorbol acetate to the mucosal solution resulted initially in an increase in the short-circuit current, which was followed by a progressive decrease. If the short-circuit current was first activated by addition of the antidiuretic hormone, arginine vasotocin, then the addition of tetradecanoyl phorbol acetate resulted only in a pronounced inhibition. The changes in the short-circuit current were the result of changes in the active influx of Na+. The effect of tetradecanoyl phorbol acetate on the intracellular potential measured under short-circuited conditions (Vscc) was time-dependent. Just after addition of tetradecanoyl phorbol acetate to the mucosal solution, Vscc depolarized; this was followed by a slight hyperpolarization, after which Vscc continued to decline. The inhibition of the Na+ transport by tetradecanoyl phorbol acetate was associated with a decline in the response to the antidiuretic hormone (arginine vasotocin), but the ability of arginine vasotocin to increase the cellular level of cAMP and to stimulate the osmotic water flow was not affected by the presence of tetradecanoyl phorbol acetate. In skin halves in which the short-circuit current was stimulated with arginine vasotocin, addition of tetradecanoyl phorbol acetate resulted in a dose-dependent inhibition of the short-circuit current, but only minor changes in Vscc were observed. The results presented suggest that the addition of tetradecanoyl phorbol acetate to the isolated frog skin first increases and then decreases the arginine vasotocin-sensitive sodium permeability of the apical membrane. This might be due to a stimulating effect of tetradecanoyl phorbol acetate on both the activation and deactivation (turnover) of the sodium channels.

Animals↗
PubMed1989

Low molecular weight heparin Novo (LHN-1) does not cross the placenta during the second trimester of pregnancy.

Unfractionated heparin (UF-H) has been the drug of choice for the treatment of thromboembolic disorders during pregnancy. Low molecular weight heparin (LMW-H) preparations may present some advantages over UF-H. They have longer half-lives and a better bioavailability after subcutaneous (s. c.) injection and may cause less bleeding. It has not yet been established whether LMW-H Novo (LHN-1) crosses the placenta. 17 women admitted for abortion during the second trimester of pregnancy (induced by application of prostaglandine PGE2 gel at a concentration of 0.25 mg/ml into the cervix) were given s. c. 35 anti-Xa units per kg of body weight of LHN-1 (Novo). 10 patients not receiving LHN-1 and their fetuses served as a control group. 7 women in whom the time interval between injection of LHN-1 and expulsion of the fetus was less than 3 h or more than 7 h were excluded from further study. In one fetus blood collection failed. Anti-Xa and anti-IIa levels increased approximately ten-fold in women receiving LHN-1 [anti-Xa units/ml from 0.02 +/- 0.01 (mean +/- SD) to 0.17 +/- 0.01, p less than 0.001; anti-Ha units/ml from less than 0.01 +/- 0.01 to 0.07 +/- 0.03], but remained below the detection limit in their fetuses as well as in the women and fetuses of the control group. We conclude that LHN-1 at these doses does not cross the placenta during the second trimester of pregnancy to suggest that LHN-1 may be a safe alternative to heparin in the management of the thromboembolic complications during pregnancy.

Abortion, Induced↗