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Biomedical subjects

H Hildebrand

Publications and source records attributed to H Hildebrand.

At least 19 recordsLinked to original sources

Adverse events leading to modification of therapy in a large cohort of patients with inflammatory bowel disease.

BACKGROUND: Adverse events leading to discontinuation or dose reduction of thiopurine therapy occur in 9-28% of patients with inflammatory bowel disease. AIMS: To evaluate the influence of thiopurine methyltransferase status and thiopurine metabolites in a large patient population for the risk of developing adverse event. METHODS: Three hundred and sixty-four patients with inflammatory bowel disease and present or previous thiopurine therapy were identified from a local database. RESULTS: The adverse event observed in 124 patients (34%) were more common in adults than children (40% vs. 15%; P < 0.001) and in low to intermediate (<or=9.0 U/mL red blood cell) than normal thiopurine methyltransferase activity (P = 0.02). Myelotoxicity developed later than other types of adverse event. An increased frequency of adverse event was observed in patients with tioguanine (thioguanine) nucleotide above 400 or methylated thioinosine monophosphate above 11 450 pmol/8 x 10(8) red blood cell. A shift to mercaptopurine was successful in 48% of azathioprine-intolerant patients and in all cases of azathioprine-induced myalgia or arthralgia. CONCLUSIONS: A pre-treatment determination of thiopurine methyltransferase status might be appropriate as patients with low to intermediate thiopurine methyltransferase activity are more prone to develop an adverse event; determination of metabolite levels can be useful in the case of an adverse event. Mercaptopurine therapy should be considered in azathioprine-intolerant patients.

Adolescent↗

European evidence based consensus on the diagnosis and management of Crohn's disease: special situations.

This third section of the European Crohn's and Colitis Organisation (ECCO) Consensus on the management of Crohn's disease concerns postoperative recurrence, fistulating disease, paediatrics, pregnancy, psychosomatics, extraintestinal manifestations, and alternative therapy. The first section on definitions and diagnosis reports on the aims and methods of the consensus, as well as sections on diagnosis, pathology, and classification of Crohn's disease. The second section on current management addresses treatment of active disease, maintenance of medically induced remission, and surgery of Crohn's disease.

Anti-Bacterial Agents↗

Malignant lymphomas in coeliac disease: evidence of increased risks for lymphoma types other than enteropathy-type T cell lymphoma.

BACKGROUND: Numerous studies have reported on the association between coeliac disease and the otherwise uncommon enteropathy-type T cell lymphoma (ETTL). A systematic risk assessment of more prevalent lymphoma entities, such as B cell and non-intestinal lymphomas, in coeliac disease has not been performed. AIMS: In light of the increasing number of patients diagnosed with coeliac disease and the unknown aetiology of malignant lymphomas, we aimed to estimate the distribution and risk of lymphoma subtypes in coeliac disease. METHODS: We reviewed and reclassified 56 cases of incident malignant lymphomas occurring in a Swedish population based cohort of 11,650 patients hospitalised with coeliac disease. The observed numbers of lymphoma subtypes were compared with those expected in the Swedish population. RESULTS: The majority (n=32, 57%) of lymphomas in the cohort were not intestinal T cell lymphomas. Significantly increased risks were observed for B cell non-Hodgkin lymphoma (NHL) (standardised incidence ratio (SIR) 2.2 (95% confidence interval (CI) 1.2-3.6); 11 non-intestinal and five intestinal) and for lymphomas of non-intestinal origin (SIR 3.6 (95% CI 2.3-5.2), 11 B and 14 T cell). Furthermore, 44% of patients with B cell NHL had a history of other autoimmune/inflammatory diseases. The relative risks for T cell NHL (SIR 51 (95% CI 35-68); n=37) and for primary gastrointestinal lymphomas (SIR 24 (95% CI 16-34); five B and 25 T cell) were markedly increased, as anticipated. CONCLUSION: Most lymphomas complicating coeliac disease are indeed related to the disease and are not of the ETTL-type. There was a remarkable aggregation of autoimmune/inflammatory disorders, female sex, coeliac disease, and B cell lymphoma.

Adolescent↗

Safety of nasal budesonide in the long-term treatment of children with perennial rhinitis.

BACKGROUND: Intranasal budesonide is an efficacious treatment for perennial allergic rhinitis. Long-term effects on safety, particularly in children, need further investigation. OBJECTIVE: To investigate the long-term safety of intranasal budesonide in children. METHODS: In an open trial, 78 children (5-15 years) with perennial rhinitis were treated with intranasal budesonide pressurized metered dose inhaler 200 microg twice daily (delivered daily dose 256 microg) for 12 months; 43 children stayed in the study for 12 additional months and were switched to aqueous suspension (400 microg delivered daily dose) for 6 months. Statural growth, bone age, ophthalmologic and rhinoscopic status, cortisol and biochemical analyses in blood and urine were monitored during the first and second years, and adverse events (AEs) were continuously recorded. RESULTS: No significant effects on statural growth and bone age, compared with reference values, were observed. Morning plasma cortisol and 24-h urinary cortisol were not changed during treatment. Patients reported 195 AEs, most commonly nasal dryness (30%), blood-tinged secretions (21%) and, among non-nasal AEs, headache (13%). Rhinoscopy revealed no signs of mucosal atrophy, ulceration, or candidiasis but some nasal dryness. No treatment-related ophthalmological or biochemical aberrations were found. Reduction of blood eosinophils and nasal symptom scores, compared with pre-treatment values, indicated the efficacy of budesonide treatment. CONCLUSION: Long-term treatment for 1-2 years with intranasal budesonide 256-400 microg daily in children with perennial rhinitis revealed no negative effects on growth or endogenous cortisol production. Local side-effects were mild and patient symptoms decreased.

Administration, Intranasal↗

Changing pattern of paediatric inflammatory bowel disease in northern Stockholm 1990-2001.

BACKGROUND: An increased incidence of paediatric Crohn's disease was reported recently by our group. AIMS: To assess the incidence and characteristics of inflammatory bowel disease (IBD) in northern Stockholm between 1990 and 2001. METHODS: All records of individuals 0-15 years of age with suspected IBD in the population based catchment area of 180000 individuals were scrutinised using defined diagnostic criteria. Patient files were searched for relatives with IBD, and for concomitant autoimmune diseases. RESULTS: A total of 152 children were diagnosed with IBD, corresponding to an overall incidence (per 100000) of IBD of 7.4. The incidence of Crohn's disease (CD) was 4.9, ulcerative colitis (UC) 2.2, and indeterminate colitis 0.2. Between 1990 and 2001, there was a marked increase in the incidence of CD while the incidence of UC was almost unchanged, leading to a net increase in the overall occurrence of IBD. There was a male dominance of CD. Fourteen per cent and 11% of patients with CD and UC, respectively, had a first or second degree relative with IBD. Eighteen per cent and 10% of patients with CD and UC, respectively, had a concomitant autoimmune disease. Ten patients with CD (10%) underwent surgery. CONCLUSIONS: The incidence of CD has increased in northern Stockholm. The current incidence is higher than that reported from other areas. Our results suggest a shift in presentation and diagnosis from UC towards CD, but also a net increase in IBD. Concomitant autoimmune disorders and family history are common in paediatric IBD.

Autoimmune Diseases↗

Interactions between cells and titanium surfaces.

The interaction between cells and implant materials is determined by the surface structure and/or surface composition of the material. In the past years, titanium and titanium alloys have proved their superiority over other implant materials in many clinical applications. This predominant behaviour is caused by a dense passive oxide layer which forms within milliseconds in oxidizing media. Titanium dioxide layers of 100 nm thickness were produced on the surface of cp-titanium grade 2, and on an experimental alloy of high vanadium content (Ti1.5Al25V) as a harmful control. The layers were produced by thermal and anodic oxidation and by coating by means of the sol-gel process. The resulting oxide layers were characterized with respect of their structure and chemical composition. In cell tests (proliferation, MTT, morphology, actin staining), the reaction of the cells was examined. It was shown that the sol-gel-produced titanium oxide layer is able to shield the cells from toxic alloying elements, with the result that the cell reaction is influenced only by the thin titanium oxide surface layer and not by the composition of the bulk material.

Actins↗

[Rheumatic fever behind acute chorea in a young girl. A case report].

This article presents the case of a 13-year old girl who was admitted to the emergency department because of rapidly evolving, seriously disabling impairments in movement and speech. Investigation led to the conclusion that her problems were caused by Sydenham's chorea as a manifestation of rheumatic fever. A neuropsychiatric examination performed one year after the onset of disease revealed a hitherto unknown mild mental retardation. The case description is followed by a clinical update on rheumatic fever focusing on cerebral manifestations. The theories concerning the existence of PANDAS--an autoimmune neuropsychiatric disorder following streptococcal infections, distinct from rheumatic fever--are presented.

Acute Disease↗

Differential response of immature rat uterine tissue to ethinylestradiol and the red wine constituent resveratrol.

The stilbene derivative resveratrol (RES) is a phytoalexin of grapes, peanuts and other fruits. It is structurally related to stilbene estrogens and an estrogenic potential of RES has recently been demonstrated in a number of in vitro studies. In this investigation, the uterotrophic responses of immature Wistar rats to subcutaneous administration of RES (18, 58, and 575 mg/ kg) and the reference estrogen ethinylestradiol (EE2; 0.3, 1, 3, 30 microg/kg) on three consecutive days were determined. Uterine weight, histopathological changes, immunohistochemical expression of nuclear estrogen receptor-alpha (ERalpha) and progesterone receptor (PR) protein, gene expression of ERalpha and PR at the messenger ribonucleic acid (mRNA) level and peroxidase induction were examined. EE2 dose dependently increased uterine weight, enlarged the uterine lumen and induced hypertrophy of epithelial, stromal and myometrial cells. Expression of ERalpha protein in epithelial, stromal and myometrial nuclei and of PR protein in epithelial nuclei was reduced in EE2-treated rats, while PR protein in stromal and myometrial nuclei was increased in a dose-dependent manner. EE2 increased messenger ribonucleic acid (mRNA) levels of uterine PR and induced peroxidase activity. In contrast, RES rather mildly decreased uterine weight, while histology did not reveal differences between controls and RES-treated rats. Expression of nuclear ERalpha protein was dose dependently decreased in epithelial, stromal and myometrial cells of RES-treated rats, while nuclear PR protein content was similar in controls and RES-treated rats. Following administration of RES, a trend toward reduced levels of ERalpha and PR mRNA was found, while no peroxidase induction occurred. Plasma levels of RES, 45 min after the administration of a single subcutaneous dose of 500 mg/kg, were in the range 1-2 microM. In summary, an estrogenic potential of RES could not be substantiated in this in vivo study, although the most effective route of administration and extremely high doses were used and plasma levels were in the range reported to be effective in vitro. Whether other pharmacological properties of RES could mediate the observed changes in RES-treated animals is discussed.

Animals↗

Inflammatory bowel disease in children and adolescents in Sweden, 1984-1995.

BACKGROUND: A prospective study of inflammatory bowel disease (IBD) in Sweden was performed to investigate whether the incidence and morbidity have changed from 1984 through 1995. METHODS: Children 15 years of age or less with IBD were included--i.e., those with a definite diagnosis of ulcerative colitis (UC) and Crohn's disease (CD) and those classified as having indeterminate colitis (IC) and probable Crohn's disease (PCD). The study covered 56.5% of the pediatric population of Sweden. RESULTS: The diagnosis of IBD was made in 639 children, which corresponds to a mean annual incidence of 5.8 per 100,000. The incidence increased from 4.6 per 100,000 per year from 1984 through 1986 to 7.0 from 1993 through 1995. It reflected an increase in UC from 1.4 to 3.2 per 100,000 per year, which is a significant yearly percentage of increase (8%; confidence interval, 2-14%; P < 0.05). In contrast, no change occurred in the incidence of CD (1.2-1.3 per 100,000). The incidence of IC and PCD also remained fairly stable. The percentages of children who underwent surgery decreased from 17.3% in the first 6 years to 4.6% in the last 6 years (P < 0.001). Surgery was performed in 27.7% of CD and 5.3% of UC cases. The median age at diagnosis was 12.2 years for UC, 13.0 years for CD, 11.2 for IC, and 11.2 for PCD. At diagnosis, 48 children (7.5%) were 5 years of age or less, whereas most of the patients were 11 years of age or more (398 children, 62.3%). CONCLUSIONS: In Sweden, the incidence of UC has increased, whereas that of CD remains the same. A significant number of children were classified with IC and PCD. In most children, IBD was diagnosed when they were 11 years old or more, but some cases were detected even in those below 6 years of age. A decrease in the frequency of surgery occurred during the study.

Adolescent↗

Immunotherapy in children with allergic asthma: effect on bronchial hyperreactivity and pharmacotherapy.

BACKGROUND: Immunotherapy has been shown to reduce allergen sensitivity to allergens such as cat and dust mite. The aim of this study was to investigate the effect of cat or dust mite immunotherapy on bronchial hyperreactivity and the need for inhaled corticosteroids in children with asthma, cat or dust mite allergy, and hay fever. SUBJECTS: Twenty-nine children, 7 to 16 years old, completed the 3-year study. They were randomly allocated to receive cat/dust mite or placebo and birch/timothy immunotherapy. METHODS: Before immunotherapy was begun and then once each year, bronchial histamine challenges were performed. Bronchial allergen challenge with the perennial allergen was done before and after the 3-year study. Pharmacotherapy was given according to a standardized protocol. RESULTS: PC20 allergen increased significantly in both the active immunotherapy group (P <.001) and in the placebo-pollen group (P <.05). PC20 histamine increased continuously in the active immunotherapy group (P <.05 and P =.002 after 1 and 3 years, respectively) and had also increased after 3 years in the placebo-pollen group (P <.05). The difference between the 2 groups was significant for PC20 allergen (P =.001) but not for PC20 histamine. There was no significant change in the dose of inhaled budesonide needed for symptom control in either of the groups. CONCLUSION: Pollen immunotherapy combined with inhaled corticosteroids results in improvement of both cat/dust mite bronchial sensitivity and hyperresponsiveness to histamine. The combination of cat or dust mite, pollen immunotherapy, and inhaled budesonide enhances this improvement. Cat immunotherapy also induces cat allergen tolerance.

Adolescent↗

Direct lysosomal uptake of alpha 2-microglobulin contributes to chemically induced nephropathy.

BACKGROUND: An abnormal accumulation of alpha 2-microglobulin (alpha 2 mu) in kidney lysosomes of male rats has been described in the nephropathy resulting from exposure to a variety of chemicals. The increment in lysosomal levels of alpha 2 mu cannot be explained by a decrease in its proteolytic susceptibility. Because a portion of alpha 2 mu resides in the cytosol of kidney cells, we decided to analyze whether this cytosolic form also contributes to the abnormal lysosomal accumulation of alpha 2 mu after exposure to chemicals. METHODS: Intact kidney lysosomes were isolated from untreated or 2,2,4-trimethylpentane (TMP) treated rats, and their ability to take up alpha 2 mu was compared. RESULTS: alpha 2 mu can be directly transported into isolated lysosomes in the presence of the heat shock cognate protein of 73 kDa (hsc73). alpha 2 mu specifically binds to a lysosomal membrane glycoprotein of 96 kDa, previously identified as the receptor for the hsc73-mediated lysosomal pathway of protein degradation. In rats exposed to TMP, the specific lysosomal transport of alpha 2 mu increases, as well as the ability of lysosomes to directly transport other substrates for this pathway. The increased lysosomal transport is mainly due to an increase in the levels of the receptor protein in the lysosomal membrane. CONCLUSIONS: The hsc73-mediated lysosomal pathway contributes to the normal degradation of alpha 2 mu in rat kidney and liver, and the activity of this pathway is increased after exposure to TMP. Our results suggest that the chemically induced accumulation of cytosolic alpha 2 mu in lysosomes is mediated by an increased rate of direct uptake into lysosomes.

Alpha-Globulins↗

Quantitation of alpha(2)-microglobulin after administration of structurally divergent chemical compounds.

alpha(2)-Microglobulin-induced nephropathy is a phenomenon which is exclusively found in adult male rats. Various chemicals are able to bind to alpha(2)-microglobulin thus inhibiting its proteolytic degradation in lysosomes of the P2 segment of the rat nephron. The accumulation of this protein in 'protein droplets' or 'hyaline droplets' leads to necrosis, followed by regeneration which possibly later results in the formation of tumours. Here we report the development of a monoclonal antibody which is specific for alpha(2)-microglobulin. It was utilized to measure alpha(2)-microglobulin concentrations in plasma and tissues, and to stain alpha(2)-microglobulin in fixed tissue slides. In two studies we administered to adult male Wistar rats two groups of compounds: (1) one group of structurally diverse compounds, which give an overview of chemical entities capable of inducing the accumulation of alpha(2)-microglobulin; and (2) another group of structurally closely related compounds (i.e. substituted benzene derivatives) for the purpose of elucidating possible structure-activity relationships. The degree of alpha(2)-microglobulin-induced nephropathy was determined by immunohistochemical staining of kidney sections. In addition, liver and kidney tissue and plasma concentrations of alpha(2)-microglobulin were not found to be elevated whereas kidney tissue concentrations were higher than the controls. The increase over control values ranged from 154% (1,4-dichloromethyl-benzene) to 321% [alpha-methyl-4-(1-methylethyl)-cyclohexanemethanol]. Comparing structurally related benzene derivatives, the hyaline droplet accumulating (HDA) potential was found to depend both on the type of substituent and its position at the aromatic ring. In general HDA activity increased in the order benzene approximately equal to phenol approximately equal to alkylated phenols < halogenated phenols < halogenated benzenes. Further QSAR studies are needed to provide a theoretical base for these observations.

Alpha-Globulins↗

Urinary antigens as markers of papillary toxicity. I. Identification and characterization of rat kidney papillary antigens with monoclonal antibodies.

Monoclonal antibodies were prepared in an attempt to develop diagnostic tools for the identification of toxic damage to the rat renal papilla. One IgG and five IgM monoclonal antibodies, reacting with antigens localized in the papilla were obtained. Three of the IgM class and the IgG class monoclonal antibodies were found to be specific for antigens localized in collecting ducts, two of them staining papillary collecting ducts more intensely than cortical collecting ducts. The IgG class antibody, termed Pap X 5C10, recognizes an antigen located at high density on the luminal side of papillary collecting duct epithelial cells and at lower density in cortical collecting duct cells. One of the IgM class monoclonal antibodies reacts with an antigen localized in epithelial cells as ascending and descending loops of Henle and of connecting tubules. Another of the IgM class monoclonal antibodies reacts with an antigen localized in the interstices of the inner medulla. All these monoclonal antibodies react with their antigens in native frozen as well as in Bouin-fixed and paraffin-embedded tissue slices. Molecular properties of the Pap X 5C10 antigen have been investigated by gel permeation chromatography, SDS-PAGE, Western blotting, and isoelectric focusing. The results indicate that the antigen in both its tissue-derived and urinary form is of large (150-200 kDa) molecular size and can be separated into two molecular species with isoelectric points of pH 7.2 and 7.3 respectively. In the urine the antigens recognized by the monoclonal antibodies form large complexes with Tamm-Horsfall protein. The antigen-containing complexes can be extracted from urine by adsorption to diatomaceous earth and elution with SDS-containing buffer. Using sandwich ELISA-type assays it is possible to determine the concentration of the antigens. In preliminary experiments we were able to show that at least three of the antigens are detected in the urine following toxic insults to the kidney. The monoclonal antibodies prepared and the tests developed thus may provide direct diagnostic access to the renal papilla and allow, for the first time, early detection of papillary damage.

Animals↗

Longitudinal growth in children and adolescents with inflammatory bowel disease.

Weight and height were followed longitudinally from birth to adulthood in children with inflammatory bowel disease living in a defined area of Sweden, 1983 through 1987; 124 children out of a possible 128 were studied. During the year preceding diagnosis, height growth velocity was significantly reduced in both ulcerative colitis and Crohn's disease. At the time of diagnosis, weight-for-height was subnormal in both children with ulcerative colitis (p < 0.05) and those with Crohn's disease (p < 0.001), while height was reduced only in children with Crohn's disease (p < 0.05). Weight for height was normalized within one year in ulcerative colitis, after the initiation of medical therapy. In Crohn's disease, weight-for-height improved during the years following diagnosis but height remained subnormal. Children with ulcerative colitis reached puberty at the normal time and their final heights became normal. In children with Crohn's disease, puberty was delayed (p < 0.001) and final height was reduced (p < 0.01). The impact of inflammatory bowel disease on growth was substantial, but it was smaller in this study than in many other published studies. The possible reasons for this difference include use of population-based material and a relatively short interval between the first symptoms and the start of treatment. Our findings indicate that, although final height was significantly reduced in children with Crohn's disease, delayed puberty reduced the negative effects on permanent adult height, to a certain extent compensating for the period of poor growth earlier in life.

Adolescent↗