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Biomedical subjects

J Nielsen

Publications and source records attributed to J Nielsen.

At least 307 records · Page 17Linked to original sources
PubMed1991

Chromosome abnormalities found among 34,910 newborn children: results from a 13-year incidence study in Arhus, Denmark.

As part of a larger prospective study of the influence of environmental factors on pregnancy, birth and the fetus, chromosome examinations have been made in 34910 newborn children in Arhus over a 13-year period. Klinefelter's syndrome was found in 1 per 576 boys, XYY in 1 per 851 boys, triple-X in 1 per 947 girls and Turner's syndrome in 1 per 1893 girls. Other sex chromosome aberrations were found in 1 per 11,637 children. The total incidence of sex chromosome abnormalities was 1 per 426 children or 2.34 per 1000. The most frequent autosomal abnormalities were that of Down's syndrome with 1 per 592 children, and reciprocal translocations with 1 per 712 children. The total incidence of autosomal abnormalities was 1 per 164 children. Chromosome abnormalities were found in 276 liveborn children and in 19 fetuses, who were aborted after prenatal chromosome examination. The combined incidence of sex chromosomal and autosomal abnormalities was 1 per 118 children or 8.45 per 1000 children.

Chromosome Aberrations↗
PubMed1991

Biochemical and physiological characterization of the efrotomycin fermentation.

An efrotomycin fermentation was characterized through physical, chemical and biochemical studies. Growth of the actinomycete, Nocardia lactamdurans occurred during the first 50 h of the fermentation cycle at the expense of glucose, protein, and triglycerides. The initiation of efrotomycin biosynthesis was observed when glucose dropped to a low concentration. Upon glucose depletion, cell growth ceased and a switch in the respiratory quotient occurred. Efrotomycin biosynthesis was supported by the utilization of soybean oil and starch. Analysis of triglyceride metabolism showed that no diglycerides or monoglycerides accumulated during the fermentation. The activity of extracellular enzymes (lipase, protease, and amylase) increased during the cell growth phase and decreased significantly after 150 h. The concentrations of DNA, tetrahydro-vitamin K2 (a membrane component), and free amino acids in the supernatant increased dramatically late in the fermentation cycle (225 h), indicating massive cell lysis. During this same time period, a reduction in cellular respiratory activity and efrotomycin biosynthesis were observed.

Amino Acids↗
PubMed1991

Skeletal size and bone mineral content in Turner's syndrome: relation to karyotype, estrogen treatment, physical fitness, and bone turnover.

Bone mineral content (BMC), bone mineral density, and metacarpal dimensions were studied in 50 women with Turner's syndrome aged 21-45 years in relation to karyotype, estrogen treatment, physical fitness, and biochemical markers of bone turnover. No differences were found between the 25 women with karyotype 45.X and women with other karyotypes. Forty-six women had received estrogen. Significant partial correlations were found between bone mineral density of the forearm and duration of estrogen treatment and physical fitness. BMC of the lumbar spine corrected for vertebral height (BMC(C)spine) was directly correlated with duration of estrogen treatment and height, marginally correlated with physical fitness, and inversely correlated with age. Outer metacarpal width was positively correlated with duration of estrogen treatment, age at initiation of therapy, and body weight. The diameter of medullary space showed negative correlation with physical fitness and height, and positive correlation with age at initiation of estrogen treatment. Cortical thickness was positively correlated with duration of estrogen treatment, physical fitness, and height. No convincing effects of estrogen could be demonstrated in women below the age of 30. Above the age of 30, all bone mineral measurements were markedly elevated in women treated for longer than the average of this age group. BMC(C)spine was inversely correlated with biochemical markers of bone formation. Our results demonstrate that estrogen treatment and physical fitness are important determinants of bone mineral status in Turner's syndrome and add to the evidence that estrogen treatment increases BMC in Turner's syndrome.

Adult↗
PubMed1991

Elective cholecystectomy increases plasma amino-acid clearance and hepatic capacity for urea synthesis for one week.

The importance of the liver in post-operative catabolism was studied in 6 cholecystectomy patients given a mixture of amino-acids as prime-continuous infusionś pre-operatively and on the 1st, 3rd, 6th and 12th post-operative day. The plasma clearance of total alpha-amino-nitrogen and of single amino-acids, the urea-nitrogen synthesis rate, and the functional hepatic nitrogen clearance were calculated. Surgery decreased fasting blood amino-nitrogen concentration by 15% (p < 0.01), and increased the plasma clearance of amino-nitrogen by 30% (P < 0.05) on the 1st, 3rd and 6th post-operative day. Surgery doubled the functional hepatic nitrogen clearance (p < 0.01) on the 1st, 3rd and 6th post-operative day. This indicates that post-operative stress catabolism is partly due to a hepatic condition by which the liver eliminates more amino-nitrogen despite lower amino-acid concentration in the blood, for one week post-operatively.

Journal Article↗
PubMed1991

Experimental in utero infection of pig foetuses with porcine parvovirus (PPV).

Pig foetuses of various gestational ages were exposed to experimental infection with porcine parvovirus (PPV) in utero. Inoculation of 40-, 50- and 60-day-old foetuses with PPV caused foetal death and mummification and spread of the infection to non-inoculated foetuses. Inoculation at 80 and 100 days gestation caused pathological lesions of various degrees whereas spread of infection occurred only sporadically. Serological examinations of foetuses of different ages suggest that immunocompetence for PPV develops before 70 days gestation. The present results strongly indicate that intrauterine spread of PPV is a route of transmission of this virus between pig foetuses.

Animals↗
PubMed1991

Retrobulbar bupivacaine irrigation for postoperative pain after scleral buckling surgery. A prospective study.

The authors conducted a prospective, randomized, double-masked clinical trial to determine if retrobulbar irrigation with bupivacaine hydrochloride 0.75% (Marcaine) has an effect on postoperative pain after scleral buckling surgery. Fifty consecutive patients undergoing scleral buckling under general anesthesia were randomized to receive either bupivacaine or balanced salt solution as a retrobulbar irrigation at the end of their retinal detachment procedure. Of the 25 patients who received bupivacaine, only three (12%) required parenteral pain relief in the first 24 hours after surgery. This was statistically significant when compared with the 18 (72%) of 25 patients requiring parenteral pain relief in the placebo group (P less than 0.0001). In addition, when questioned about their perception of the degree of postoperative pain, patients in the control group rated their level of pain as significantly more severe than did patients in the bupivacaine group. The authors conclude that retrobulbar irrigation with bupivacaine is a safe and effective way to achieve postoperative pain relief after surgery for scleral buckling.

Adolescent↗
PubMed1991

Transient idiopathic dystonia in infancy.

The authors report eight otherwise normal children who presented with transient dystonic postures and/or movements in infancy. The anomalies appeared during the first months of life, progressed during a period then gradually disappeared at follow-up (from 3 months to 5 years). Differential diagnosis with primary orthopedic problems, cerebral palsy and early progressive CNS disease may be difficult at onset of the symptoms. Transient dystonia is probably one of the numerous mechanisms responsible for some abnormalities of tone, posture and movement in infancy and may account for some of the cases labeled as "transient cerebral palsy". Our cases resemble those described by Willemse (19) as "benign idiopathic dystonia in the first year of life".

Cerebral Palsy↗
PubMed1991

Reproducibility of leukotriene D4 inhalation challenge in asthmatics. Effect of a novel leukotriene D4/E4-antagonist (SR 2640) on leukotriene D4-induced bronchoconstriction.

We have studied the reproducibility of a bronchial leukotriene (LT) provocation test in asthmatics, and the effect of prior treatment with an oral leukotriene D4/E4 antagonist (SR 2640) on LTD4-induced bronchoconstriction in nine asthmatics in a double-blind placebo-controlled randomized cross-over trial. The reproducibility of the bronchial leukotriene provocation test was high. For a specific patient, the replication variance is 0.2303, and the standard deviation is thus 0.4799, corresponding to 48%, i.e. one halving of the dose or half doubling of the dose. SR 2640 antagonised LTD4 induced bronchoconstriction causing a mean shift of 48% to the right of the dose-response curve as compared with placebo (95% confidence interval being 11-137%). This study demonstrates that bronchial LTD4 provocation test is a safe and reproducible method in asthmatics, and that the method can be used to detect LT-antagonism; furthermore that SR 2640 is a weak LTD4-antagonist in asthmatics.

Adult↗
PubMed1991

Immunologic tests of specific antibodies to organic acid anhydrides.

The outcome of immunologic tests of antibodies directed against hapten conjugates of organic acid anhydrides and human serum albumin (HSA) has been studied in workers exposed to phthalic anhydride (PA), methyltetrahydrophthalic anhydride (MTHPA), hexahydrophthalic anhydride (HHPA), and methylhexahydrophthalic anhydride (MHHPA). HSA conjugates of PA, MTHPA, HHPA, MHHPA, and maleic anhydride (MA) have been prepared and used in the tests. The hapten densities (HD) of the conjugates were varied by different molar ratios of hapten and macromolecule in the preparative procedure. Skin prick reactions to MTHPA-HSA increased with rising HD over the range 6-13 mol/mol. The achieved HD was tested by spectrometric and gas chromatographic methods. In RAST of IgE antibodies MTHPA-HSA with HD six and 25 showed significantly lower bindings than conjugates with intermediate HD. There was a good correlation between skin prick tests and RAST. Of 234 workers tested [MTHPA (n = 145), and HHPA (n = 89)], 45 had a skin prick reaction greater than or equal to 50% of the histamine reaction (1 mg/ml). All but two of these were RAST positive (RAST value greater than 0.3%; 0.3% upper range in 147 controls; MTHPA, n = 63; HHPA, n = 84). Nine RAST positive workers had no obvious skin prick reaction. However, their RAST values were low (less than 0.8%). In exposed workers, the ELISA value of specific IgG antibodies to MTHPA-HSA showed optimal values when tested with the HD 13 conjugate.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme-Linked Immunosorbent Assay↗
PubMed1991

Atrial natriuretic peptide concentrations in umbilical cord plasma from pre-eclamptic women.

Atrial natriuretic peptide (ANP) was measured in arterial and venous umbilical cord plasma at the time of delivery by cesarean section in pre-eclamptic (n = 7) and normal women (n = 6). In addition venous samples were obtained from pre-eclamptic (n = 7) and normal pregnant women (n = 7) near term. ANP plasma levels were higher in pregnant women with pre-eclampsia than in normal pregnant women (27.9 +/- 4.4 [mean +/- SEM] and 14.1 +/- 2.5 pmol l-1, respectively, P less than 0.05). Immediately after delivery plasma ANP in pre-eclamptic mothers was 66.7 +/- 12.8 pmol l-1 compared to 13.9 +/- 2.2 pmol l-1 in normal mothers (P less than 0.01). However, in the pre-eclamptic group the levels of ANP in arterial and venous umbilical cord plasma (19.5 +/- 4.2 and 16.7 +/- 4.3 pmol l-1, respectively) were significantly (P less than 0.01) lower than ANP levels in arterial and venous cord plasma (39.6 +/- 1.0 and 31.1 +/- 4.2 pmol l-1, respectively) from normal mothers. It is concluded that the increased ANP plasma level in pre-eclamptic women originates from a maternal source. In addition, since the ANP level is lower in cord plasma than in maternal plasma in pre-eclampsia, feto-placental volume homeostasis may also be changed in pre-eclampsia.

Adult↗
PubMed1991

Pattern of cutaneous inhibition of the propriospinal-like excitation to human upper limb motoneurones.

1. The pattern of cutaneous inhibition of non-monosynaptic excitation (or 'propriospinal-like' excitation) to various species of motoneurones-wrist flexors and extensors, biceps and deltoid - was investigated in man. 2. Changes in the firing probability of individual voluntarily activated motor units were studied following various stimuli. The effects of weak cutaneous stimuli applied to the skin of either the palmar or the dorsal side of the fingers on propriospinal-like excitation evoked by stimulation of different mixed nerves (median, radial, musculo-cutaneous) were investigated. 3. Cutaneous stimuli were found to produce an inhibition with a very specific pattern, which depended on the afferent input evoking the excitation. Thus, the median nerve-induced excitation of wrist and elbow flexors was depressed by cutaneous afferents from the palmar side but not from the dorsal side of the fingers; the radial nerve-induced excitation of wrist extensors was only depressed from the dorsal side: the musculo-cutaneous nerve-induced excitation of motor units of various wrist, elbow and shoulder muscles was depressed from both sides. 4. It is argued that this pattern implies that the excitation is mediated to the motoneurones through different subsets of neurones, organized according to the afferent input. 5. The functional significance of the pattern of cutaneous inhibition is discussed and it is argued that it could contribute to an appropriately timed termination of a movement mediated through the propriospinal system.

Adult↗
PubMed1991

The seal death in Danish waters 1988. 2. Virological studies.

Mass abortions and high mortality were observed in harbour seals in Danish waters during 1988. Severe pneumonia and emphysema were typical clinical and post-mortem findings. Virological studies were carried out to identify the cause of the epidemic. Although seal herpesvirus (SeHV) was isolated in 23 of 114 animals this virus was subsequently found not to be the primary cause of the disease. Following the observation of seroconversion against canine distemper virus (CDV) in diseased seals (Osterhaus & Vedder 1988) a CDV-like morbillivirus (phocine distemper virus, PDV) was identified in organs of diseased animals. It is concluded that the epidemic was caused by introduction of PDV into a highly susceptible population presumably free from morbillivirus infection. The origin of PDV remains unknown but evidence of prior morbillivirus infection has been found in arctic and antarctic seal populations.

Animals↗
PubMed1991

Awakening and recovery of simple cognitive and psychomotor functions 2 h after anaesthesia for day-case surgery--total intravenous anaesthesia with propofol-alfentanil versus thiopentone-alfentanil.

Fifty-seven patients undergoing minor out-patient gynaecological procedures were allocated to one of two total intravenous anaesthesia regimes: propofol and alfentanil or thiopentone and alfentanil. Diazepam was given orally as premedication. To assess objectively the quality of recovery, the patients underwent a number of tests pre-operatively and two hours post-operatively. The time to opening of eyes and orientation was equal in both groups, as was the recovery of the tested cognitive and psychomotor functions after 2 h, when the score in both groups had returned to baseline. We conclude that the use of propofol instead of thiopentone for shorter surgical procedures gives no advantage as regards length of stay in hospital.

Adolescent↗
PubMed1990

[Measurement of systolic finger blood pressure with a pulse oximeter].

In order to investigate whether the pletysmographic curve on a pulse oximeter can be employed for measurement of the systolic finger blood pressure, the authors compared the method with a strain-gauge method and undertook 160 measurements with a finger cuff on 11 healthy volunteers. By varying the pressure in two cuffs placed on the arm, the blood pressure in the finger could be altered from normal to very low values. The difference between the connected values was analysed and it was found that the difference between strain-gauge and pulse oximeter measurements read on the printer on employment on a new volunteer will be -0.9 +/- 3.8 mmHg. If the blood pressure is read on a manometer, the same difference will be -1.5 +/- 5.2 mmHg. The authors consider that the method is interesting in view of future employment for assessment of the collateral circulation in the hand but they recommend further investigations on patients with occlusive arterioschlerotic disease in the upper limbs.

Adult↗
PubMed1990

[Convulsions after flumazepil].

Two cases of convulsions following intake of the benzodiazepine antagonist, flumazepil, are presented. The etiology is discussed and special precautions are recommended for the diagnostic employment of the preparation.

Adult↗
PubMed1990

[Surgical treatment of abdominal aorta aneurysm 1983-1987. A multicenter study. 1266 operations, development and early results].

During the years 1983-1987, 1,266 operations for abdominal aortic aneurysm (AAA) were carried out in eight surgical departments with vascular surgical function. The activity increased constantly corresponding to 311 patients in 1987 or 50% more than in 1983. During this period the distribution between patients subjected to elective operation and those operated upon as emergencies was very uniform. In the latter group, only a slight increase in the number of AAA patients with rupture was observed. The risk of complications was low with a significant decrease in the need for dialysis. The early mortality was constant for the patients subjected to elective operation remained constant about 5.5%. A marked decrease in the early mortality was observed for the patients operated upon as emergencies with rupture from 63 to 50% and without rupture from 37 to 25%. At the conclusion of the period, ultrasonic scanning became the preoperative investigation of election and introduction of an aortic prosthesis the method of operation of election. Patients with AAA should be recognized so that elective surgery can be offered before a condition endangering life develops.

Adult↗