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N Nyhlin

Publications and source records attributed to N Nyhlin.

13 recordsLinked to original sources
PubMed2006

Systematic review: microscopic colitis.

BACKGROUND: Collagenous and lymphocytic colitis are fairly common causes of chronic non-bloody diarrhoea, especially in elderly female. AIM: To present a systematic review of microscopic colitis. METHODS: A PubMed search using the MeSH terms microscopic colitis, collagenous colitis, lymphocytic colitis and chronic diarrhoea was performed. RESULTS: Annual incidence of each disorder is 4-6/100,000 inhabitants. The aetiology is unknown. Clinical characteristics are well described and there is an association with autoimmune diseases. Budesonide is the best-documented short-term treatment of collagenous colitis. In meta-analysis pooled odds ratio for clinical response after 6-8 weeks of treatment was 12.3 (95% CI: 5.5-27.5) in comparison with placebo. The evidence for bismuth subsalicylate is weaker and the effectiveness of other alternatives such as loperamide, cholestyramine, aminosalicylates, probiotics, or Boswellia serrata extract is unknown. Although unproven, in unresponsive severe disease azathioprine or methotrexate may be tried. No controlled trials have been carried out in lymphocytic colitis. The long-term prognosis of microscopic colitis is good, serious complications are rare and there is no increased mortality. CONCLUSIONS: Clinical and epidemiological aspects of microscopic colitis are well described. Budesonide is the best-documented short-term therapy in collagenous colitis, but the optimal long-term strategy needs further study. Controlled treatment data of lymphocytic colitis are awaited for.

Aged↗
PubMed2002

Reduction of free radical activity in amyloid deposits following liver transplantation for familial amyloidotic polyneuropathy.

OBJECTIVES: Liver transplantation halt the progress of familial amyloidotic polyneuropathy (FAP). Oxidative stress has been implicated in amyloid toxicity and formation. The objective of this study was to establish whether markers for oxidant stress and antioxidant capacity change following liver transplantation in patients with FAP. DESIGN: Morphometric and biochemical study. SETTING: Tertiary referral centre. SUBJECTS: Duodenal biopsy samples from 16 patients, taken before and after liver transplantation were used for morphometry. Serum samples from 14 patients, seven of whom had received transplants, were analysed regarding antioxidant capacity. INTERVENTION: Liver transplantation. MAIN OUTCOME MEASURES: Immunohistochemistry was used to stain for the lipid peroxidation product 4-hydroxynonenal (HNE), and Congo red staining was used for amyloid detection. Positive areas were quantified by point counting. Total antioxidant capacity (TAC) was measured with a colourimetric assay. RESULTS: In tissue, a decrease of HNE was noted after liver transplantation, whereas no significant changes were detected for amyloid deposits. No difference between transplanted and not transplanted patients was noted for total antioxidant capacity measured in serum. CONCLUSION: To our knowledge, this is the first description of a reduction of markers for free radical activity after cessation of amyloid formation. The findings implicate that amyloid formation in transthyretin (TTR) amyloidosis generates oxidative stress, whereas amyloid deposits as such are less toxic to sourrounding tissues.

Adult↗
PubMed2000

Liver transplantation restores endocrine cells in patients with familial amyloidotic polyneuropathy.

BACKGROUND: The aim of this study was to investigate familial amyloidotic polyneuropathy, Portuguese type patients' endocrine cell content in the stomach and duodenum before and after liver transplantation, and to relate the findings to the patients' gastrointestinal disturbances. METHODS: Ten liver-transplanted familial amyloidotic polyneuropathy, Portuguese type patients and 10 healthy controls were seen. Endocrine cells were identified by immunohistochemistry and quantified with computerized image analysis. The activity of the cells was appraised by measurements of the cell secretory index and nuclear area. Clinical symptoms were obtained from the patients' medical records. RESULTS: After transplantation, a significant increase of several endocrine cell types were noted, and the pretransplant depletion of several types of endocrine cells disappeared. For no type of endocrine cell was any difference compared with controls noted after transplantation. There was no significant decrease of the amount of amyloid in the biopsies after liver transplantation. The patients' symptoms remained generally unchanged after transplantation, although a substantial time lapse between pretransplant evaluation and transplantation was present. CONCLUSIONS: Liver transplantation restores the endocrine cells in the upper part of the gastrointestinal tract. The restoration was not correlated with an improvement of the patients' symptoms. No decrease of the amyloid deposits was noted.

Adult↗
PubMed2000

Advanced glycation end product in familial amyloidotic polyneuropathy (FAP).

OBJECTIVES: Advanced glycation end products (AGE) are present in amyloid deposits in beta2-microglobulin amyloidosis, and it has been postulated that glycation of beta2-microglobulin may be involved in fibril formation. The aim of this paper was to ascertain whether AGE occur in amyloid deposits in familial amyloidotic polyneuropathy (FAP). SETTING: Department of Medicine, Umeå University Hospital and First Department of Internal Medicine, Kumamoto University School of Medicine. DESIGN: The presence of AGE was sought immunohistochemically and biochemically in amyloid-rich tissues from patients with FAP. SUBJECTS: Biopsy specimens from nine patients and 10 controls were used for the immunohistochemical analysis. For amyloid preparation, vitreous samples from three FAP patients were used. RESULTS: Immunohistochemical studies using a polyclonal anti-AGE antibody revealed positive immunoreactivity in intestinal materials, but the pattern of reactivity was unevenly distributed; it was often present in the border of amyloid deposits, or surrounding them. Non-amyloid associated immunoreactivity was also observed in a few regions of the specimens, although the AGE-positive structures were situated in areas containing amyloid deposits. Western blotting of purified amyloid from the vitreous body of FAP patients revealed a significant association of AGE with amyloid fibrils. CONCLUSION: The immunoreactivity for the AGE antibody suggests that AGE may be involved in fibril formation in FAP.

Adult↗
PubMed1999

Colonic enteric nervous system in patients with familial amyloidotic neuropathy.

The colonic enteric nervous system was investigated in autopsy specimens from 12 patients with familial amyloidotic neuropathy (FAP) and 9 controls. The infiltration of amyloid deposits in the enteric nervous system was studied by double staining for amyloid and nerve elements. The myenteric plexus was immunostained for protein gene product (PGP) 9.5, vasoactive intestinal peptide (VIP), substance P and nitric oxide synthase (NOS). The immunostained nerve elements were quantified by computerised image analysis. Double staining revealed that there was no amyloid infiltration in the ganglia, or in the nerve fibres in the colonic enteric nervous system of FAP patients. The relative volume density of PGP 9.5-immunoreactive nerve fibres in both the circular and the longitudinal muscle layers in FAP patients did not differ significantly from that of controls. The relative volume density of VIP-immunoreactive nerve fibres in the circular muscle layer was significantly decreased in FAP patients compared with controls, but not in the longitudinal layer. The number of VIP-immunoreactive neurons/mm2 myenteric ganglia was significantly decreased in FAP patients. There were no statistical differences in the relative volume density for substance P- and NOS-immunoreactive nerve fibres between FAP patients and controls, nor was there any difference between FAP patients and controls regarding the number of NOS- and substance P-immunoreactive neurons/mm2 myenteric ganglia. It is concluded that the colonic enteric nervous system as a whole is intact and is not damaged by amyloid infiltration. The present observation of a reduction of VIP-immunoreactive nerve fibres and neurons in myenteric plexus of FAP patients might be one of the factors that contribute to the motility disorders seen in FAP patients.

Adult↗
PubMed1999

Colonic endocrine cells in patients with familial amyloidotic polyneuropathy.

OBJECTIVE: To establish whether the endocrine cell number is affected in the colon in Japanese FAP patients. SETTING: Department of Medicine, Umeå University Hospital and Department of Internal Medicine and Pathology, University Hospital, Kumamoto, Japan. SUBJECTS: Autopsy colon tissue specimens from 11 FAP patients and nine controls as well as 12 control biopsy specimens were included in the study. MEASUREMENTS: Endocrine cells in the colon were detected by immunohistochemistry and quantified by computerized image analysis. RESULTS: The autopsy material showed a slight autolysis. Neither enteroglucagon nor pancreatic polypeptide positive cells could be detected in the autopsy material, but were present in biopsy material. There was no statistical difference between autopsy and biopsy specimens regarding the number of peptide YY (PYY), somatostatin and serotonin cells. No significant differences were noted in PYY, somatostatin and serotonin immunoreactive cells in FAP patients compared to autopsy controls, though PYY cells tended to be decreased and serotonin and somatostatin cells tended to be increased in FAP patients. CONCLUSION: The difference between the Swedish and Japanese patients in the endocrine cell content points to the possibility of involvement of other factors than the endocrine cell depletion of the colon might be involved in the pathogenesis of gastro-intestinal dysfunction in FAP. The tendency of PYY to decrease in Japanese FAP might contribute to the development of diarrhoea in these patients.

Adult↗
PubMed1999

Endocrine cells in the upper gastrointestinal tract in relation to gastrointestinal dysfunction in patients with familial amyloidotic polyneuropathy.

Gastrointestinal (GI) dysfunction is a common complication of familial amyloidotic polyneuropathy (FAP). In previous reports, a decreased content of small and large intestinal endocrine cells has been found in patients with FAP and it has been suggested that this may contribute to the development of GI disturbances. The aim of the present study was to investigate the endocrine cell content in the stomach and duodenum of FAP patients, and to correlate the findings with gastric emptying. Fifteen patients with FAP were included in the study. Twenty-eight subjects with macroscopically and histologically normal mucosa were used as controls for endocrine cell contents and 14 healthy subjects for gastric scintigraphy. The endocrine cells were identified by immunohistochemistry and quantified with image analysis. Gastric emptying time was detected by scintigraphy and endoscopy. The number of chromogranin A-immunoreactive (IR) cells was reduced in all investigated parts of the GI tract except bulbus duodeni. Gastrin/CCK cell content was reduced in duodenum, but tended to be increased in antrum of the stomach (P = 0.07). Otherwise, the content of all other endocrine cells types in the upper GI tract was reduced compared with controls. A correlation with malnutrition was found for gastric inhibitory polypeptide and secretin cell content in bulbus duodeni. Gastric scintigraphy disclosed delayed gastric emptying of solid food, but the finding was not correlated to the decreased content of neuroendocrine cells. The severity of endocrine cell depletion was not correlated to duration of GI disturbances. The present study showed that the endocrine cells of the stomach are affected in FAP patients and that the abnormalities in the upper GI endocrine cells occur early during the course of the disease.

Adult↗
PubMed1998

Histochemical detection of 4-hydroxynonenal protein in Alzheimer amyloid.

The presence of lipid peroxidation product in amyloid deposits from seven patients with Alzheimer disease and nine with non-Alzheimer disease was examined immunohistochemically by means of an affinity purified anti-HNE antibody to hydroxynonenal (HNE), a marker of lipid peroxidation. A positive reaction was found in amyloid deposits in all the specimens examined: most of the perivascular areas (89%) where amyloid deposition was confirmed by Congo red staining, showed immunoreactivity with the antibody in the specimens of Alzheimer disease. Twenty-one percent of senile plaques which were also stained by Congo red staining reacted with this antibody. Several perivascular cells were also stained by anti-HNE antibody. In other neurons both in Alzheimer and non-Alzheimer disease patients, only a few percent reacted with this antibody and no statistical difference was observed between them. These results verify that lipid peroxidation via free radical injury occurs in amyloid deposits in Alzheimer amyloid. Since HNE has been identified as a cytotoxic metabolite of free radical injury, amyloid deposits in the tissue may exhibit a toxic effect during the generation process of HNE.

Aged↗
PubMed1997

Oxidative stress is found in amyloid deposits in systemic amyloidosis.

Oxidative stress in human amyloid deposits from patients with systemic amyloidosis, such as familial amyloidotic polyneuropathy (FAP), primary amyloidosis, and secondary amyloidosis, was examined immunohistochemically by means of an affinity purified anti-hydroxynonenal (HNE) antibody to HNE, a marker of lipid peroxidation. Furthermore, the levels of thiobarbituric acid reactive substances (TBARS), which is another marker of lipid peroxidation, and the levels of protein carbonyl, a maker of protein modifications by free radicals, were determined in FAP patients and healthy controls. Affinity purified anti-HNE antibody reacted with amyloid deposits in all types of amyloid tissues examined. Significantly higher levels of TBARS and protein carbonyl were found in amyloid rich tissues of FAP patients compared with those in the control subjects. These results verify that lipid peroxidation via free radical injury occurs in amyloid deposits in systemic amyloidosis. The protein modifying properties of free radicals increase the likelihood that they play an important role in the amyloid formation process.

Adult↗
PubMed1997

Evaluation of immunohistochemical staining of human duodenal endocrine cells after microwave antigen retrieval.

The effect of microwave antigen retrieval on the immunostaining of human duodenal endocrine cells in formaldehyde-fixed, paraffin-embedded material was investigated. The sections were immunostained by the avidin-biotin complex (ABC) and immunogold-silver autometallography (IGSS) methods with and without prior microwave treatment. Dilutions of up to 1:30,000 of the following antisera/antibodies were used: anti-chromogranin A, anti-chromogranin AB, anti-secretin, anti-gastrin, anti-gastric inhibitory polypeptide, anti-somatostatin and anti-serotonin. The detection threshold for all the antibodies was lower after antigen retrieval, and the primary antibody could be used in higher dilutions. The dilutions varied for different antibodies and were between two and ten times the optimal dilution without antigen retrieval. At extremely high dilutions of, or without, the primary antibody, non-specific staining of some lymphocytes and the mucus of some goblet cells was observed when the avidin method was applied, but not with the immunogold technique. This phenomenon was not observed when optimal dilution or a lower dilution was used. This seems to have been caused by the binding of the avidin-biotin complex to epitopes in these structures unmasked by microwave treatment when competition with specific binding sites was absent.

Adult↗
PubMed1996

A new simple and rapid screening method for variant transthyretin-related amyloidosis.

To screen for transthyretin (TTR) related amyloidosis rapidly and reliably, we have developed a new method using a centrifugal concentrator device and electrospray ionization mass spectrometry (ESI-MS). Only 50 microliters of serum is needed for the analysis. After preparation of the samples with anti-TTR antibody they were passed through a 1000 kDa cut off centrifugal concentrator which retained the antibody. By analyzing the obtained filtrate with ESI-MS, variant forms of TTR was detected. TTR (Met30), with a molecular weight 32.0 Da higher than the normal form of TTR, was found in all FAP patients examined. In 3 liver transplanted FAP patients, the abnormal peaks had disappeared. In conclusion, The TTR Met30 mutation was easily detected in serum samples by electrospray ionization mass spectrometry after centrifugal concentration. The proposed method is simple to perform, as no HPLC is required, and offers a possibility to screen populations for TTR related amyloidosis.

Adult↗
PubMed1996

Impact of gastrointestinal dysfunction on survival after liver transplantation for familial amyloidotic polyneuropathy.

Liver transplantation is the only effective treatment of familial amyloidotic polyneuropathy type I (FAP). The aim of the present investigation was to identify factors at the time of submission for transplantation that had impact on survival, with special reference to gastrointestinal disturbances. All 28 liver-transplanted FAP patients evaluated at Umeå University Hospital were included in the study. A modified body mass index was used to assess nutritional status. Intestinal examinations were performed to diagnose bile acid malabsorption, gastric retention, and bacterial contamination of the small bowel. A significantly improved survival rate was found for patients in a good nutritional state (P = 0.002). Peripheral neurological symptoms were unrelated to survival, whereas increased mortality was found for patients with bile acid malabsorption (P < 0.05). Bacterial contamination and gastric retention were common complications of the disease. In conclusion, malabsorption and malnutrition have a profound impact on the outcome of liver transplantation for familial amyloidotic polyneuropathy.

Adult↗