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Biomedical subjects

J Hansen

Publications and source records attributed to J Hansen.

At least 235 records · Page 13Linked to original sources
PubMed1990

Baseline and phosphoramide mustard-induced sister-chromatid exchanges in cancer patients treated with cyclophosphamide.

Determinations of baseline sister-chromatid exchanges (SCE) have been used extensively as indicators of previous mutagen exposure in both animals and humans. Hypersensitivity to mutagen-induced SCE levels has also been studied in a variation on the basic technique as an indication of previous mutagen exposure in a stressed or provocative test system. The genotoxicity of the alkylating anti-cancer drugs including cyclophosphamide (CP) has been examined previously by determining baseline SCEs in peripheral blood lymphocytes from treated cancer patients. This study examined the in-vivo genotoxic effects of CP therapy by comparing baseline and phosphoramide mustard (PM)-induced SCEs in therapeutically (in-vivo) treated cancer patients with SCE levels in newly diagnosed, but not treated patients. Therapeutically treated patients showed statistically higher baseline SCE frequencies than untreated control patients with a mean SCE/cell of 6.95 vs. 5.25, p less than 0.016. When net SCE values (induced minus baseline) were determined in PM-exposed cells in-vitro both at low dose (0.1 microgram/ml PM) and high dose (0.25 microgram/ml PM) however, the difference was not significant between therapeutically treated and untreated control patients. The return to control SCE levels as a function of time since last therapeutic treatment was also evaluated and no difference was found between the rate of decline of PM-induced SCEs and baseline SCE levels over time.

Breast Neoplasms↗
PubMed1989

[Donors of cadaver kidneys. Reactions of relatives illustrated by a questionnaire study].

Fifteen relatives of 11 patients from whom kidneys were removed after death with the object of transplantation were interviewed, three or more years after the death of the patient. The object of the investigation was to illustrate whether the procedure hitherto employed in Denmark, in which the relatives are asked for their permission for removal of the organs, is satisfactory. The authors were particularly interested to know how the surviving relatives experienced the decision to give permission for removal of the kidneys from their relative. The most important conclusion of this investigation is that the majority of the relatives were satisfied afterwards with the permission they had given and found that this decision had made an otherwise tragic situation meaningful.

Attitude to Death↗
PubMed1989

Graft-versus-host disease as adoptive immunotherapy in patients with advanced hematologic neoplasms.

The occurrence of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation for leukemia is thought to decrease the probability of recurrence. To study this effect (called adoptive immunotherapy) we modified the prophylaxis of GVHD in patients with advanced hematologic neoplasms (mostly leukemia) who received bone marrow transplants. Patients under 30 years of age were randomly assigned to one of three regimens of post-transplantation immunosuppression: Group I (n = 44) received a standard course of methotrexate for 102 days after transplantation, Group II (n = 40) received an abbreviated (11-day) course of methotrexate, and Group III (n = 25) received the standard course of methotrexate plus viable buffy-coat cells from the marrow donors. All 109 patients received cyclophosphamide (60 mg per kilogram of body weight on each of two days), total-body irradiation (2.25 Gy daily for seven days), and unmodified marrow from HLA-identical sibling donors. The frequency of GVHD of Grades II through IV was 25 percent in Group I, 59 percent in Group II, and 82 percent in Group III (P = 0.0001). The incidence of chronic GVHD, however, did not differ significantly among the groups (33, 51, and 44 percent, respectively), nor did the five-year probability of recurrence of disease (38, 45, and 33 percent, respectively). However, mortality from causes other than cancer was 34 percent in Group I, 45 percent in Group II, and 64 percent in Group III (I vs. III, P = 0.024); the deaths were due primarily to infections complicating the course of GVHD. With a median follow-up of 5.1 years (range, 3.9 to 7.4), disease-free survival was 41 percent in Group I, 30 percent in Group II, and 24 percent in Group III (the differences were not statistically significant). We conclude that abbreviating methotrexate prophylaxis or infusing donor buffy-coat cells increased the incidence of acute GVHD and related mortality without altering the incidence of chronic GVHD or the recurrence of malignant disease.

Adolescent↗
PubMed1989

An analysis of the inhibition of replication of HIV and MuLV by some 3'-blocked pyrimidine analogs.

Some 3'-blocked pyrimidine analogs were synthesized and tested as inhibitors of replication of human immunodeficiency virus (HIV) and Moloney-murine leukemia virus (MuLV). The analogs were of 3 kinds: (1) analogs of 3'-azido-3'-deoxythymidine (AZT) in which the C-5 CH3 of the base was exchanged for H (AZU) or C2H5 (AZEU); (2) 3'-fluoro-3'-deoxythymidine (FLT) and analogs thereof, in which the C-5 CH3 of the base was exchanged for H (FLU), C2H5 (FLEU) or nC3H7 (FLPU); (3) the threo analogs of AZT (AZT increases) and AZU (AZU increases). All analogs were less active inhibitors of HIV replication than AZT, except FLT, which was as active as AZT. The 3'-fluoro analogs and AZEU did not inhibit MuLV replication at non-cytotoxic concentrations. Oral administration of FLT to MuLV-infected mice result in antiviral effects only at toxic drug levels. AZU and FLU were less potent inhibitors of HIV replication than AZT or FLT, but the 2'-deoxy uridine analogs were less cytotoxic to human embryonic fibroblasts than the thymidine analogs. The 5'-triphosphates of AZU, AZT, AZEU, FLT and FLEU were tested as inhibitors of the HIV- and MuLV-reverse transcriptases. Ranking of the Ki/Km values for HIV-RT resulted in the following order of potency of the 5'-triphosphates AZT = FLT greater than AZU greater than AZEU greater than FLEU. The 5'-triphosphates of AZEU, FLT and FLEU did not inhibit the MuLV-RT, which explains, in part, the lack of effect of these analogs against MuLV replication. The threo forms (azido "up") of AZU and AZT were less active inhibitors of HIV replication than the erythro forms (azido "down"). A 15N-NMR and 1H-NMR study showed that the furanose moieties of analogs with the azido function "up" assume a conformation distinct from that of the analogs with azido "down". This is due to intramolecular stabilisation of the "N" conformer in the threo ("up") diastereomer, due to interaction of the azido functions with the nucleobase and possibly the OH group of C-5' of the furanose. As discussed, this conformation might explain the decreased biological activity of threo forms compared with the erythro forms.

Animals↗
PubMed1989

ts1, a mutant of Moloney murine leukemia virus-TB, causes both immunodeficiency and neurologic disorders in BALB/c mice.

BALB/c mice infected with ts1, a mutant of Moloney murine leukemia virus-TB, develop generalized body wasting, profound neurologic disorders, severe thymic atrophy and lymphopenia due to destruction of T lymphocytes and drastic immunodeficiency. ts1 was found not only able to infect T lymphocytes but also to impair their function. In addition, ts1 also infects and induces syncyntia formation in macrophages. The genetic determinant(s) responsible for ts1's ability to induce immunodeficiency has been localized to the env gene.

Animals↗
PubMed1989

A phase I-II trial of cisplatin, hyperthermia and radiation in patients with locally advanced malignancies.

A Phase I-II trial testing the addition of systemic cisplatin (CDDP) to local hyperthermia and radiation was conducted to determine the dose of cisplatin that is tolerable once weekly for 6 weeks and to estimate the therapeutic potential of this trimodality combination in patients with locally advanced malignancies. Cisplatin at 20 mg/m2 (4 patients), 30 mg/m2 (8 patients), and 40 mg/m2 (12 patients) was given rapidly (over 5-10 min) i.v. after prehydration with 1 liter of normal saline. After approximately two-thirds of the cisplatin dose had been delivered, microwave hyperthermia was begun and continued for 60 min; the target minimum tumor temperature was 43 degrees C. Following hyperthermia, a 400 cGy fraction of radiation was delivered to the tumor. On other days during the treatment weeks, additional 200 cGy fractions were given to total doses of 6,000-6600 cGy in patients with full radiation tolerance or 2400-3600 cGy in patients with limited radiation tolerance. The 24 patients in this trial had a median age of 57 years and the predominant sites/tumor types were head and neck/squamous cell carcinoma (9) and chest wall/breast adenocarcinoma (9). Seventeen of the 24 treated tumors (70%) had previously been irradiated. Eighteen patients (75%) had received prior chemotherapy and nine patients (38%) had previously been treated with cisplatin. Bone marrow suppression was dose limiting in patients heavily pretreated with chemotherapy and chest wall radiation. No significant toxicities were observed at the 20 and 30 mg/m2 dose levels, but 5 of the 12 patients (42%) treated at 40 mg/m2 required modification of the cisplatin dose because of blood count suppression in four patients and mild renal dysfunction in one patient. Each of the patients with bone marrow suppression, however, had been heavily pretreated except for one patient with thrombocytopenia due to hypersplenism. Nausea and vomiting were mild with use of a standard, multiagent antiemetic regimen. Twelve patients (50%) attained a complete regression (CR) and 12 patients (50%) a partial regression (PR). Complete regression appeared to correlate with small tumor volumes (115 cc for CR versus 199 cc for PR patients) and higher tumor temperatures (4.6 average minimum equivalent minutes at 43 degrees C in CR versus 2.0 min in PR patients). Local toxicities included second degree burns in 12 patients (50%) and third degree burns in 6 (25%), but all burns healed in 4-12 weeks without surgical intervention.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

Proallergens of formaldehyde applied in patch testing of formaldehyde contact allergy.

The ability of the nonliquid, nonvolatile proallergen of formaldehyde, N-hydroxymethylsuccinimide, to test for contact allergy to formaldehyde has been investigated by in vitro penetration studies in human epidermis. Compared with the standard test, 1% formaldehyde in water, N-hydroxymethylsuccinimide equal to 0.8 mg formaldehyde gave a similar penetration profile. This is explained by cleavage of N-hydroxymethylsuccinimide into formaldehyde and carrier (succinimide) by transepidermal water on the surface of the skin. Results were confirmed by a guinea pig maximazation test on animals sensitized to formaldehyde and in a preliminary clinical study on nine patients with known allergy to formaldehyde.

Administration, Cutaneous↗
PubMed1989

[Sonographic diagnosis of pneumothorax].

The sonographic appearances of the pleura were studied in 20 normals and in eight patients with radiologically confirmed pneumothoraces. In all 20 normals it was possible to demonstrate the respiratory excursion of the visceral pleura. Moreover, the margin between pleura and aerated lung parenchyma was marked by artifacts resembling a comet's tail. In all eight patients with pneumothoraces pleural air could be inferred by the absence of pleural movement and of the comet-tail artifacts. In emergency situations, where it is not possible to obtain radiographs, or to obtain them with sufficient speed, sonography may make a crucial contribution to the diagnosis of a pneumothorax.

Adolescent↗
PubMed1989

Effect of 10 mg and 20 mg omeprazole daily on duodenal ulcer: double-blind comparative trial.

One-hundred and seventy-one patients with endoscopically proven duodenal ulcers were allocated at random to double-blind treatment with 10 or 20 mg of omeprazole in the morning for up to 4 weeks. Patients completed the study if ulcer healing and pain relief had occurred at 2 weeks. A total of 155 patients completed the trial. Patients treated with 20 mg of omeprazole daily responded significantly more rapidly than those treated with 10 mg of omeprazole daily (P less than 0.001; Cochran-Mantel-Haenszel test covering both time points), cumulative healing rates at 2 and 4 weeks were 74% (58/78) and 91% (71/78), respectively. The corresponding rates in the group treated with 10 mg daily were 48% (39/81) and 75% (58/77). Pain relief was again more pronounced during treatment with the larger dose (P less than 0.05; stratified Wilcoxon test). No major clinical or biochemical side effects were noted. An omeprazole dose of 20 mg daily is preferable to a lower dose for the treatment of duodenal ulcer disease in the short term.

Adolescent↗
PubMed1989

Graft-versus-host disease prevention by methotrexate combined with cyclosporin compared to methotrexate alone in patients given marrow grafts for severe aplastic anaemia: long-term follow-up of a controlled trial.

Forty-six patients with aplastic anaemia (median age 23 years) were given cyclophosphamide followed by infusion of marrow from an HLA-identical family member. To evaluate postgrafting prophylaxis for graft-versus-host disease (GVHD), the patients were entered into a randomized prospective trial comparing a combination of methotrexate and cyclosporin (n = 22) to methotrexate alone (n = 24). Methotrexate/cyclosporin significantly reduced the incidence and severity of acute GVHD and improved early survival. This report updates the results of the randomized trial with followup ranging from 3 to more than 6 years. The methotrexate/cyclosporin regimen did not interfere with sustained engraftment, and there were no significant differences in the incidence of early or late graft rejection among the two treatment groups (10% v 4%). The incidence of chronic GVHD was higher among methotrexate/cyclosporin-treated patients (58% v 36%; P = 0.18). Two patients in each treatment group still require treatment for chronic GVHD, while treatment is no longer needed in the other patients. Projected 4-year survival is 73% in patients given methotrexate/cyclosporin compared to 58% in patients given methotrexate alone (P = 0.16). Having achieved a reduction in the incidence of acute GVHD and associated early mortality without impairing engraftment, it is clear that future progress in marrow grafting for aplastic anaemia must come in the area of chronic GVHD.

Adolescent↗
PubMed1989

Interaction of cinnamaldehyde (a sensitizer in fragrance) with protein.

Formation of a cinnamaldehyde-protein conjugate in the skin by reaction of cinnamaldehyde with nucleophilic groups in proteins is considered to be responsible for the observed immunogenicity. The kinetics of the reaction of bovine serum albumin with cinnamaldehyde in aqueous solution at 30 degrees C have been investigated, and the rate of formation of conjugate over the pH range 6.4-10.5 showed a first-order dependence on cinnamaldehyde concentration. The cinnamaldehyde binding sites on the protein appeared mostly or exclusively to be the thiol groups of cysteine residues.

Acrolein↗
PubMed1989

Penetration of the fragrance compounds, cinnamaldehyde and cinnamyl alcohol, through human skin in vitro.

The delivery of cinnamaldehyde and cinnamyl alcohol in fragrance through human skin has been investigated by in vitro penetration studies using full thickness human skin. Cinnamaldehyde was transformed to cinnamyl alcohol and cinnamic acid in the skin. The transformation took place in model protein solution, bovine serum albumin, as well as in skin homogenates. After conjugation of cinnamaldehyde with the protein, a lag time was observed after which cinnamyl alcohol and cinnamic acid were released. On the other hand, cinnamyl alcohol was not transformed in detectable amounts to either cinnamaldehyde or cinnamic acid during penetration of the skin.

1-Propanol↗
PubMed1989

Chemical, pharmaceutical and clinical standardization of the TRUE Test caine mix.

The development of the caine mix patch of the TRUE TestTM involved extensive formulation work to obtain optimal release, stability and clinical function. Hydroxypropyl cellulose, ordinarily used in the TRUE TestTM, induced crystallization and inadequate release of benzocaine. Addition of the crystal poison glucose caused rapid degradation of the caines. Polyvinylpyrrolidone (PVP) proved to be a vehicle which incorporated the caines in a stable preparation on the patch. Rapid release of the caines from this vehicle when applied on membranes was confirmed by in vivo patch test studies.

Adult↗
PubMed1989

TestPack Chlamydia, a new rapid assay for the direct detection of Chlamydia trachomatis.

TestPack Chlamydia (Abbott Laboratories) is a rapid enzyme immunoassay for the direct antigen detection of Chlamydia trachomatis in endocervical specimens. The assay is self-contained, requires no specialized equipment, and yields results in less than 30 min. The clinical performance of TestPack Chlamydia versus chlamydial cell culture was evaluated with a total of 1,694 paired endocervical specimens. Discordant samples were further investigated by immunofluorescent staining and by Chlamydiazyme immunoassay, with confirmatory procedures. The sensitivity of TestPack Chlamydia with less-than-48-h-old specimens was 76.5%, while culture sensitivity was 86.7%. TestPack Chlamydia specificity was determined to be 99.5%. These results indicate that TestPack Chlamydia is an accurate test for chlamydial infection, with a positive predictive value of 96.2%. This assay is suitable for low-volume chlamydial testing in physician offices, clinics, and smaller laboratories.

Antigens, Bacterial↗
PubMed1989

Cross-sensitization patterns in guinea pigs between cinnamaldehyde, cinnamyl alcohol and cinnamic acid.

Guinea pig maximization tests (GPMT) were performed with cinnamon substances. There was a certain degree of cross-reactivity between cinnamaldehyde, cinnamyl alcohol and cinnamic acid as animals sensitized to cinnamaldehyde reacted to the challenge with the three substances. Animals sensitized to cinnamyl alcohol reacted to cinnamyl alcohol and cinnamaldehyde, but not to cinnamic acid. Cinnamic acid did not sensitize guinea pigs. Compared to the challenge concentration for cinnamaldehyde, approximately a 15 times higher concentration of cinnamyl alcohol and a 25 times higher concentration of cinnamic acid were required to give positive reactions in animals sensitized to cinnamaldehyde. This could not be explained by differences in permeability properties, as the penetration profiles of the three substances through guinea pig skin in vitro showed permeability coefficients of the same order of magnitude under the test conditions. The study suggests that cinnamaldehyde is the "true" allergen, while cinnamyl alcohol and cinnamic acid are transformed in the skin to cinnamaldehyde, before contact allergic reactions can occur.

1-Propanol↗