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Biomedical subjects

H Nielsen

Publications and source records attributed to H Nielsen.

At least 127 records · Page 7Linked to original sources
PubMed1995

Systemic high-dose ranitidine in the treatment of psoriasis: an open prospective clinical trial.

We report the results of an open, prospective study on the efficacy of systemic ranitidine in the treatment of psoriasis. Twenty patients suffering from moderate to severe psoriasis were included in the study. The median pretreatment PASI score was 15.7 (range 6.0-24.7). The patients were treated with oral ranitidine 300 mg twice a day for 6 months; no other medication was allowed during the study period. Eighteen patients completed the study. The median PASI score was reduced from 15.7 to 14.5, 9.1 and 5.7, after 1, 3 and 6 months of treatment, respectively (P < 0.00001). A significant reduction in PASI score was evident at 3 months of treatment. A mild to moderate deterioration occurred in 15 patients within the first month of treatment, but this was followed by improvement during prolonged treatment in most patients. No other clinical and/or biochemical side-effects were observed. Eight patients continued therapy with ranitidine after the study was completed, and none of these patients relapsed during a follow-up period of 12-18 months. The results of the present study suggest that ranitidine may be a beneficial and safe treatment for psoriasis. In addition, high-dose, long-term ranitidine treatment appears to be free from severe adverse effects.

Administration, Oral↗
PubMed1995

Brain and muscle oxygen saturation during head-up-tilt-induced central hypovolaemia in humans.

Near-infrared spectrophotometry-determined cerebral (ScO2) and muscle oxygen saturations (SmO2) were followed in 15 volunteers during passive 50 degrees head-up-tilt-induced central hypovolaemia, and in nine volunteers during ventilatory manoeuvres affecting arterial carbon dioxide tension. During head-up tilt, mean arterial pressure [MAP, 88 (77-118) to 97 (80-136) mmHg, median and range] and heart rate [HR; 66 (49-77) to 87 (42-132) beats min-1 P < 0.01] increased, but after 22 (1-45) min they declined [to 61 (40-91) mmHg and 69 (38-109) beats min-1, respectively, P = 0.001] and pre-syncopal symptoms developed. Central hypovolaemia was indicated by an increased thoracic electrical impedance, and a decreased cardiac output and central venous oxygen saturation. The arterial oxygen saturation, pulmonal oxygen uptake and skin temperatures remained constant. The ScO2 remained stable at 72 (62-77)% until the pre-syncopal incidence, when it decreased to 62 (31-73)% (P = 0.001), and tilt down made it increase to 75 (36-87)% (P < 0.05) before the recovery value was established. In contrast, SmO2 decreased during tilting [75(70-87) to 65 (53-70)%], and recovered to 70 (53-83)%, P < 0.01) during the hypotensive episode. The end-tidal CO2 tension decreased only during tilt-up. The ScO2 decreased, and SmO2 increased during hyperventilation, and ScO2 increased during breathing of 5% carbon dioxide. Rebreathing from a bag made SmO2 decrease and resulted in a biphasic ScO2 response: it first increased and subsequently decreased. Cardiovascular changes during tilt were not reflected in skin temperature. The ScO2 reflected the maintained autoregulation of cerebral blood flow until the perfusion pressure decreased markedly. In contrast, SmO2 mirrored muscle vasoconstriction early during tilt, and vasodilatation when pre-syncopal symptoms appeared.

Adult↗
PubMed1995

Effects of diabetes, insulin treatment, and osmolality on contractility of isolated rat resistance arteries.

The effects of osmolality, diabetes, and insulin-treatment on microvascular contractility were examined in mesenteric resistance arteries (internal diameter approximately 250 microns) isolated from streptozotocin-induced diabetic rats, streptozotocin-induced diabetic rats treated with 1-3 U insulin/day during the week before being killed, and age- and sex-matched control rats. Vessels were mounted in a microvascular myograph for isometric tension recording and responses were generated in physiological salt solutions with varying amounts of glucose or mannitol added. The passive response (expressed as the diameter the vessels would maintain if relaxed and exposed to a transmural pressure of 100 mmHg), the maximal response to noradrenaline, and the response produced by partial depolarization with 50 mmol/l potassium were not dependent on glucose or mannitol concentrations of the bathing medium; also, these responses were not dissimilar in vessels from the three groups of rats tested. The sensitivity to noradrenaline, however, was inversely related to the concentration of glucose (P < 0.01) and mannitol (P < 0.01) of the bathing medium without significant differences in slopes of regression lines between rat groups. Moreover, vessels from streptozotocin-induced diabetic rats were less sensitive to noradrenaline than were vessels from control rats; vessels from insulin-treated streptozotocin-induced diabetic animals had the lowest sensitivity to noradrenaline. These data suggest that osmolality, diabetes, and insulin-treatment independently affect microvascular sensitivity to the endogenous neurotransmitter, noradrenaline.

Aging↗
PubMed1995

Cross-reactive antigens shared by Pseudomonas aeruginosa, Helicobacter pylori, Campylobacter jejuni, and Haemophilus influenzae may cause false-positive titers of antibody to H. pylori.

Cystic fibrosis (CF) patients suffer from many of the gastrointestinal conditions which occur in non-CF individuals, e.g., dyspepsia and peptic ulceration. These symptoms may be caused by Helicobacter pylori but could also be due to either pancreatic insufficiency or the intensive antibiotic treatment used in CF patients. Since CF patients chronically infected with Pseudomonas aeruginosa produce antibodies against a wide range of antigens, including antigens common to many other bacteria, e.g., GroEL and lipopolysaccharide, we studied, by the Western blot (immunoblot) technique, the specificity of immunoglobulin G antibodies to H. pylori in Danish CF patients chronically infected with P. aeruginosa, CF patients without P. aeruginosa infection but with Haemophilus influenzae infection, patients with dyspeptic ulcers associated with H. pylori, and patients recovering from acute Campylobacter jejuni or Campylobacter coli infection. Sera from CF patients with chronic P. aeruginosa or H. influenzae infection and patients recovering from acute C. jejuni infection cross-reacted with H. pylori antigens. A strong cross-reacting protein antigen at approximately 14 kDa and minor cross-reactive antigens at approximately 27, 30, and 60 kDa (the heat shock protein GroEL is equivalent to the common antigen of P. aeruginosa) could be demonstrated. The results of this study show that high immunoglobulin G antibody titers against H. pylori in CF patients cannot be regarded as indicating present or past H. pylori infection unless their specificity is proven by absorption studies.

Antibodies, Bacterial↗
PubMed1995

Neutrophil degranulation by Helicobacter pylori proteins.

Mucosal biopsy specimens from patients with Helicobacter pylori infection in gastric antrum contain an increased amount of myeloperoxidase. This study was performed to elucidate the interaction of H pylori sonicate protein(s) and neutrophils concerning myeloperoxidase release. Neutrophil degranulation with myeloperoxidase release was examined in a direct stimulating assay. Priming activity of H pylori was examined after preincubating neutrophils in sonicate, either crude or modified by heat treatment, pronase inactivation and dialysis, and stimulating with N-formyl-methionyl-leucyl-phenylalanine (fMLP) or serum opzonised zymosan (OZ). It was found that H pylori sonicate protein(s) stimulates neutrophil degranulation with myeloperoxidase release in a concentration dependent way. The activity was distinct from fMLP and capable of priming the subsequent fMLP and OZ response. Experiments with the modified bacterial sonicate suggest the activity is caused by a protein, but the findings show that non-protein molecules, for example, lipopolysaccarides were also part of the H pylori sonicate priming activity. The increased mucosal myeloperoxidase in H pylori associated disease can be a direct consequence of bacteria derived stimulation of inflammatory neutrophils.

Bacterial Proteins↗
PubMed1995

Activation of phagocytes by Helicobacter pylori correlates with the clinical presentation of the gastric infection.

Only a minority of subjects with Helicobacter pylori infection develop clinical gastroduodenal disease. It is unclear whether host factors or bacterial virulence properties contribute to the pathogenic mechanisms. We have previously demonstrated a 25-35-kDa protein with phagocyte stimulatory activity in bacterial sonicates. Protein preparations were made from 15 H. neutrophil and monocyte chemotaxis and chemiluminescence was assessed with cells from healthy donors in comparison with N-f-methionyl-leucyl-phenylalanine and C5a anaphylatoxin. The potency of bacterial protein(s) for induction of monocyte chemiluminescence was significantly higher for strains from ulcer patients (1 +/- 1 microgram/ml induced > or = twofold increase of control response) and chronic active gastritis (1 +/- 1 microgram/ml) compared with superficial gastritis (> 1,000 microgram/ml, p<0.05). Neutrophil activation was also significantly more potent with strains from duodenal ulcer disease. The chemotactic activity of bacterial preparations was not significantly different between the groups. We conclude that bacterial strains with pronounced activation of phagocytes are associated with the presence of clinical ulcer disease, supporting the existence of ulcerogenic strains.

Adult↗
PubMed1995

Serodiagnosis of Helicobacter pylori infection in patients with human immunodeficiency virus infection.

In contrast to the established role of Helicobacter pylori gastritis in gastritis and duodenal ulcer in general, conflicting results have been reported in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome. The seroprevalence during early HIV infection is unknown. We retrospectively studied 102 patients with HIV infection early during the infection and in most cases in asymptomatic patients. Serological IgG antibody response to H. pylori was assessed by ELISA. Compared with an age-matched control group the seroprevalence of H. pylori positivity was not significantly different (19% vs 25%). We observed no association with CD4 counts, p24 antigen, antibiotic prophylaxis with sulfamethoxazole/trimethoprim or antiretroviral treatment. In 54 of 83 patients initially seronegative a second examination was performed after a median of 24 months (range 3-60 months) and 2 patients had H. pylori seroconverted, indicating an incidence of new infection of 2%/year. In conclusion, previous reports have underestimated the prevalence of H. pylori infection in HIV patients, which seems to be similar to that in an HIV-negative population.

Adult↗
PubMed1995

In vivo and in vitro binding of fatty acids to genetic variants of human serum albumin.

The effect of genetic variation on the fatty-acid binding properties of human serum albumin was studied by two methods involving the use of sequenced albumin variants isolated from bisalbuminaemic persons. First, the amount of total fatty acid and of several individuals fatty acids bound to eighteen different variants and to their normal counterpart (Alb A) were determined by a gas-chromatographic micromethod. Pronounced effects on total fatty acid binding were found for the glycosylated variants Alb Redhill (modified in domain II) and Alb Casebrook (domain III) in which cases a 1.7- and 8.6-fold increment, respectively, was found. By contrast, Alb Malm0 (glycosylated in domain I) carried the same amount of fatty acid as Alb A. The fatty acid loads on three chain-termination variants were normal. Finally, eight albumins with single amino-acid substitutions bound normal amounts of fatty acid, whereas one bound increased (1.7-fold) and three albumins bound diminished amounts (0.5-0.6-fold). Information on nineteen individual fatty acids was also obtained. It was possible, based on the type of changes in their relative amounts, to group the fatty acids as follows: (a) = C6:0 - C14:0, (b) = C15:0 - C18:0, (c) = C16:1 - C18:1, and (d) a group composed of essential and conditionally essential fatty acids. For nine variants, in most cases modified in domain III, large changes in one or more of these groups were observed. The changes were not related to any changes in total fatty acid load. Second, the binding of laurate, as a representative of the group (a) fatty acids, to delipidated albumin preparations was studied at pH 7.4 by a kinetic dialysis technique. The first stoichiometric association constant for binding to Alb Redhill (0.7-fold) and Alb Casebrook (0.6-fold) was diminished as compared with binding to their corresponding Alb A, whereas binding to one chain-termination variant and three single amino-acid substitutions were all unaffected by the mutation.

Chromatography, Gas↗
PubMed1995

Effect of chronic and experimental jaw muscle pain on pain-pressure thresholds and stimulus-response curves.

Pain-pressure thresholds (PPTs) and stimulus-response (S-R) curves in masseter muscles and index fingers of 11 female patients with chronic jaw-muscle pain were compared with that of 11 matched control subjects. Experimental hyperalgesic and hypoalgesic conditions in the masseter muscles of control subjects were induced by intramuscular injection of 5% saline and of local anesthetic, respectively. The PPTs were found to be significantly lower in the masseter muscles of pain patients than in those of control subjects. The mean slopes of the S-R curves were significantly steeper for the masseter muscles of pain patients (0.481 +/- 0.213) than of control subjects (0.274 +/- 0.201, P < .0256). There were no statistically significant differences in PPTs or S-R curves for the index finger. The PPTs in masseter muscles of control subjects were not significantly affected by injection of 5% saline; however, the slopes of the S-R curves for the masseter muscles were significantly steeper for saline-injection values compared to baseline values (21.7% +/- 29.6%, P < .037). Injection of local anesthetic into masseter muscles of control subjects increased the PPTs significantly and reduced the slopes of the S-R curves significantly as compared to baseline values (-22.9% +/- 34.6%, P < .0155). The present results suggest that PPTs and S-R curves are valuable tools for quantitative description of chronic and experimental jaw muscle pain.

Adult↗
PubMed1994

[Chronic fatigue syndrome--a defined unity?].

Chronic fatigue syndrome (CFS) is characterized by a sudden onset of an influenza-like illness followed by marked chronic fatigue and abnormal exercise-induced exhaustion. The precise pathogenesis of this disorder is unknown, but viral infection triggering immune imbalance has been suggested. The literature on CFS is reviewed. We find no consistent support for chronic viral infection or immunological dysfunction. The data in the published studies are rather conflicting, and further research in order to identify parameters that differentiate CFS from other disorders is necessary.

Diagnosis, Differential↗
PubMed1994

[Chronic fatigue syndrome--a controlled cross-sectional study].

Twenty-one patients fulfilling the Center for Disease Control criteria for chronic fatigue syndrome (CFS) were examined in a controlled study. Viral antibodies and tests evaluating the immune system were investigated in the patients and in a control group of 21 sex- and age-matched individuals. Production in vitro of the predominantly T-cell-derived cytokines interleukin-2 and interferon-gamma was significantly higher in patients with CFS compared the control group. Furthermore, the serum concentrations of IgA and IgE were significantly lower in patients with CFS; however, the values were within the normal reference range. All other variables were similar in the two groups. This study does not suggest a clearly disordered immune system or a chronic viral infection as a major pathogenetic factor in CFS. Longitudinal studies of immunological and virological parameters in CFS are warranted as are studies on patients that are severely handicapped.

Adolescent↗
PubMed1994

[Needles for bone marrow examination].

Over the past decades, numerous new bone biopsy needles have been introduced. Pathological investigation requires sufficiently large and well-preserved specimens. This article reviews the literature concerning the quality of the instruments. Comparison of the various types of needles in controlled studies is not available. Bone-marrow biopsy is discussed in the context of obtaining optimal specimens and choice of biopsy needle.

Biopsy, Needle↗
PubMed1994

Identification, molecular cloning, expression and chromosome mapping of a family of transformation upregulated hnRNP-K proteins derived by alternative splicing.

Acidic nuclear proteins (M(r) between 64,000 and 66,000; pI 4.9 to 5.5) that are highly upregulated in transformed cells and that belong to the hnRNP-K family have been identified using a monoclonal antibody (mAB B4B6) that distinguish between quiescent and proliferating human keratinocytes. The family, which is composed of four major proteins (hnRNPs-K A, B, C and D) and their modified forms, is present in similar overall levels in quiescent and proliferating normal keratinocytes although clear differences were observed in the levels of some of the individual variants. Immunofluorescence staining of proliferating normal keratinocytes with mAB B4B6 showed that about 40% of the keratinocytes, corresponding mainly to G1 and to half of the cells in S-phase, reacted with the antibody depicting a dotted, nucleoplasmic staining that excluded the nucleolus. Only 3 to 4% of the quiescent keratinocytes reacted with the antibody while simian virus 40 (SV40) transformed keratinocytes (K14) stained constitutively throughout the cell cycle. Using mAB B4B6 as a probe we cloned a cDNA coding for one member of the family (hnRNP-K B) and this was used to screen for additional family members. Sequencing of the positive clones revealed four different cDNAs, all resulting from alternative splicing of a common primary transcript of a gene that mapped to chromosome 9. Expression of the cDNAs in the vaccinia virus system confirmed their identity as hnRNPs-K A, B, C and D and showed that their modified forms are phosphorylated. All four hnRNPs bound poly(rC) on NorthWestern blots, although the more acidic of the phosphorylated forms, did so at a much reduced level. hnRNP-K has been implicated in pre-mRNA metabolism of transcripts containing cytidine-rich sequences and our results point towards a role during cell cycle progression.

Alternative Splicing↗
PubMed1994

[Postoperative rehabilitation of patients operated for lumbar disk prolapse. An analysis of the socioeconomic consequences].

A new postoperative rehabilitation program consisting of intensive back training without low back pain being the limiting factor has been tested in a clinical trial and found effective compared to a more traditional training program. The objective of the present investigation was to evaluate the social economic consequences (cost-effectiveness analysis) of the introduction of this new program as a general offer for all patients undergoing first time discectomy for a herniated lumbar intervertebral disc in Denmark. Ninety-six consecutive patients operated on at the Dept. of Neurosurgery. Copenhagen County Hospital of Glostrup were randomized into two intervention groups. One group was offered intensive back training and the other group was offered traditional back training. A historical control group was also selected. The effectiveness of the training programmes was evaluated by a "Low Back Pain Rating Scale" and by the number of patients out of employment one year after operation. The social economic evaluation showed that the new intensive training programme was more effective. Savings in medical expenditure are to be expected if the new programme is offered. Further, as more people are to be expected to keep their employment, a production gain for the society can be expected as well as reduced public expenditures on social benefits.

Adult↗
PubMed1994

[Carbon monoxide poisoning due to lack of maintenance of a natural gas boiler].

Carbon monoxide causes one third of all poisoning deaths in Denmark, but is probably grossly underdiagnosed. We present a case where an elderly couple was admitted on several occasions to local hospitals with a variety of symptoms and signs; e.g. flu-like symptoms, generalized seizures, polycythaemia, chest pain, and ventricular tachycardia. The correct diagnosis, carbon monoxide poisoning, was made when the dog in the family was found dead; examination of the natural gas boiler revealed sooting, clogging of the flue, and a carbon monoxide concentration above 0.2 percent. The natural gas boiler had not been checked after installation five years earlier. Natural gas installations are becoming still more prevalent in Danish homes, but present regulations regarding the installations are apparently not yet able to prevent new incidents of carbon monoxide poisoning.

Accidents, Home↗
PubMed1994

[rhG-CSF treatment in cyclic neutropenia. Continuous versus intermittent rhG-CSF treatment in cyclic neutropenia].

Cyclic neutropenia is a stem-cell disorder characterized by regular 21-day cyclic fluctuations in the number of neutrophils in the blood and bone marrow. The neutropenic periods may be complicated by fever, stomatitis and severe infections. In this case report only daily continuous and later intermittent treatment with recombinant human granulocyte colony-stimulating factor (two micrograms/kg) administered subcutaneously effectively prevented recurrent infections.

Adult↗
PubMed1994

Ranitidine improves postoperative monocyte and neutrophil function.

BACKGROUND: The histamine H2-receptor antagonist ranitidine hydrochloride has been shown to improve trauma-, blood transfusion-, and sepsis-induced immunosuppression. OBJECTIVE: To evaluate the effect of ranitidine on postoperative impairment in monocyte and neutrophil function. METHODS: Twenty-four patients undergoing major elective abdominal surgery were randomized to receive adjuvant treatment with ranitidine hydrochloride (100 mg) administered twice a day intravenously from skin incision for 4 days, followed by oral ranitidine hydrochloride (150 mg) administered twice a day for 5 days (n = 11), or no adjuvant treatment (n = 13). Blood monocyte and neutrophil chemotaxis and chemiluminescence were analyzed before the operation and on postoperative days 1, 3, and 9. RESULTS: Monocyte chemotaxis to C5a in the 13 control patients was significantly decreased on day 1 compared with day 0. Chemotaxis in the 11 ranitidine-treated patients increased significantly from day 0 to day 1 (P < .01 between groups). Neutrophil chemiluminescence to zymosan and N-f-methionyl-leucyl-phenylalanine was significantly increased in control patients on day 1 compared with day 0 (P < .05), while ranitidine reduced chemiluminescence to zymosan insignificantly on day 1 (P < .07 between groups). Five of the 13 control patients developed postoperative infectious complications, which were related to decreased monocyte chemotaxis to C5a and increased neutrophil chemiluminescence to zymosan, compared with noninfected patients. A significant difference (P < .05) in chemiluminescence to zymosan between infected and noninfected control patients was observed on day 3 before clinical signs of infectious disease could be detected. There were no infectious complications in ranitidine-treated patients. CONCLUSION: These results support previous studies on the effect of ranitidine to improve postoperative immunosuppression.

Adult↗