PubMed Health⌕ Search

Biomedical subjects

M Alavaikko

Publications and source records attributed to M Alavaikko.

At least 19 recordsLinked to original sources

The influence of economic interests on alcohol control policy: a case study from Finland.

Finland's participation in the European Union has meant that Finnish markets have been opened to international competition and that the traditional alcohol policy decision-making that revolved around Alko, the state alcohol monopoly company, has become impossible. The influence of private commercial interests increased in the 1990s but not in a straightforward manner. They had their biggest influence in the mid-1990s when the 1994 Alcohol Act was drafted and accepted. After that the influence of commercial interests has declined, and nowadays the alcohol question is again discussed in terms of public health and safety and drinking among young people. Integration did not lead to the expected deregulation of alcohol control but to new forms of regulation, where EU authorities such as the Commission and the EU Court also play an important role. Alcohol policy-making is now more transparent, and free trade and competition without interference are much more stressed than previously. These are the new frames of public intervention in the alcohol question, both in the trade of alcoholic beverages and in the taking care of individuals harmed by the use of alcohol.

Alcohol Drinking↗

Loss of heterozygosity for chromosome 11 in primary human breast tumors is associated with poor survival after metastasis.

A common feature of the malignant progression of human tumors is loss of heterozygosity (LOH) for various regions of their genomes. Such events encompassing chromosomes 11p15 and 11q23 are frequent in human breast tumors. Here, we have analyzed genetic and clinical characteristics of a series of primary breast tumors in order to determine: (a) a more finely mapped estimate of the involved regions; (b) whether there is a relationship in the presentation of LOH between the two regions; and (c) whether a correlation exists between such LOH and any of the clinical parameters pertaining to each patient. We found that LOH for 11p15.5 and 11q23 occurred in 35 and 46% of the 86 primary breast carcinomas, respectively, but in none of the 10 benign tumors examined. The minimal region of LOH for 11p15 was in the approximately 2-megabase region between loci TH and D11S988. Twenty-nine % of the tumors showed LOH simultaneously at both 11p15 and 11q23, 5% had LOH only at 11p15.5, and 15% had LOH only at 11q23. Among these genetic groups, clinical features such as tumor size, involvement of auxiliary nodes, histological subtype, tumor grade, estrogen/progesterone receptor status, and patient age were not markedly different. However, LOH of 11q23 (either alone or in conjunction with LOH of 11p15) in the primary tumor was found to be highly predictive of aggressive postmetastatic disease course with substantially reduced survival (P = 0.0004; log rank test). We also observed a slight trend toward a more rapid development of metastatic lesions, without obvious site specificity, in patients with primary tumors showing LOH for chromosome 11 in the pathogenesis of human breast cancer; we suggest that its effects are late in the progression of this disease.

Breast Neoplasms↗

[Apoptosis in Hodgkin's disease].

Previous studies have concentrated on the proliferative behaviour of the neoplastic cell compartment in Hodgkin's disease (HD). The aim of the current investigation was to analyse the frequency of programmed cell deaths in Hodgkin and Reed-Sternberg (HRS) cells in the different subtypes of HD and to correlate this phenomenon with the expression of the bcl-2 oncogene. For this purpose, we investigated paraffin-embedded material from 63 cases of HD. Oncogene expression was determined by immunohistochemistry with the monoclonal antibody bcl-2-124. The detection of apoptotic cells was facilitated by application of the in situ end-labelling (ISEL) technique. Our results confirmed that bcl-2 expression is low in the lymphocyte-predominant subtype of HD. Apoptotic cells were found in all subtypes to a variable extent and were not significantly associated with any particular subtype. Interestingly, there was no correlation of bcl-2 expression and the presence or absence of apoptotic HRS cells. Hence, other factors must be operative in the regulation of programmed cell death in HD. Such mechanisms have been described for lymphocytes under various conditions, such as negative selection in germinal centres and within the thymus, DNA damage due to irradiation, and cellular cytotoxicity.

Apoptosis↗

Lymphocytic gastritis and Helicobacter pylori infection in gastric lymphoma.

Lymphocytic gastritis and primary gastric lymphoma are rare conditions with unknown aetiology. It has recently been suggested that Helicobacter pylori has a role in the pathogenesis of both of them. The occurrence of lymphocytic gastritis and H pylori was studied in a series of patients with primary gastric lymphoma. The cases of primary gastric lymphomas (n = 35) diagnosed in years 1970-1993 were identified. The specimens of 22 cases contained gastric mucosa sufficiently so that the number of intra-epithelial lymphocytes, severity of gastritis, and occurrence of H pylori could be studied. Lymphocytic gastritis was detected in seven of 22 patients (32%), and in most cases both in antral and body mucosa. Atrophy of the body glands was significantly more severe in lymphocytic gastritis patients. H pylori was detected in 13 of all 22 patients (59%); two of seven lymphocytic gastritis patients (29%), and 11 of 15 (73%) of patients without lymphocytic gastritis were H pylori positive. Patients with gastric lymphoma have significantly increased prevalence of lymphocytic gastritis. Rarity of H pylori in these patients might be connected with atrophic changes in body mucosa. Further studies are needed to show the significance of lymphocytic gastritis as a precursor of gastric lymphoma.

Adult↗

Loss of heterozygosity in sporadic human breast carcinoma: a common region between 11q22 and 11q23.3.

The development of sporadic human breast cancer is associated with the accumulation of genetic alterations on several chromosomes. In the case of chromosome 11, loss of heterozygosity (LOH) at loci on the short arm has been well documented and suggests the presence of a suppressor gene(s) at 11p15.5. However, the evidence for similar events on the long arm is less compelling. Here, we determined the prevalence of LOH for chromosome 11q in 44 malignant and 3 benign cases of unselected sporadic breast tumor samples. We found that alteration of chromosome 11q is common in the pathogenesis of breast cancer as 19 of 44 (43%) malignant tumor specimens exhibited LOH. Eleven (58%) of these genetic alterations were specific to the long arm of the chromosome. The smallest region of shared LOH places the target between 11q22 and 11q23.3, the same general region frequently altered in cancers of the ovary, colon, skin, and uterine cervix, perhaps indicating the location of a tumor suppressor gene or genes of importance in each of these different tumor types.

Breast Neoplasms↗

Refinement of regional loss of heterozygosity for chromosome 11p15.5 in human breast tumors.

The familial association of breast cancer with other tumors such as rhabdomyosarcoma that show loss of heterozygosity (LOH) for chromosome 11p15 as well as limited analyses showing LOH for chromosome 11p in breast tumors suggests the presence of a pleiotropic tumor suppressor gene in this region. In order to test this idea, we analyzed DNA samples for 50 matched normal and tumor tissues from unselected breast cancer patients for LOH at loci throughout the chromosome 11p15.5 region. We found that 12.5% of informative cases showed LOH at HRAS1, 26.8% at TH, and 33.3% at both D11S860 and HBB, providing genetic support for this hypothesis. In contrast to previous observations which excluded the involvement of 11p15.5 regions distal to the HBB cluster, our results indicate that the subregion between TH and HBB is a critical region in breast cancer. This region is identical to that identified for the clinically associated tumor, rhabdomyosarcoma, and thus warrants intensive molecular analysis.

Base Sequence↗

Tenascin in reactive lymph nodes and in malignant lymphomas.

Tenascin is an extracellular matrix protein which accumulates in the stroma of various malignant and some benign neoplasms. This has been verified in several immunohistochemical studies. The distribution of tenascin immunoreactivity in lymphatic tissues and neoplasias, however, has not been thoroughly studied. In this investigation we analyzed tenascin immunoreactivity in several benign and malignant lymphatic lesions, including both Hodgkin's and non-Hodgkin's lymphomas. In benign lymph nodes, faint reticular immunoreactivity could be observed in the lymphatic tissue. In benign reactive hyperplasias, a stronger reticular pattern of tenascin immunoreactivity was observed in the interfollicular and medullary areas, while the lymphoid follicles contained only a few positive fibers. A similar immunoreactivity was observed in malignant follicular lymphomas. In diffuse lymphomas, a diffuse meshwork of positively stained fibers was seen. This was also the case for the three cases of Hodgkin's disease of the lymphocyte-predominance nodular subtype. There was no difference in the intensity of the immunoreactivity between benign and malignant disorders. However, in Hodgkin's disease of the nodular sclerosis and lymphocyte-depletion subtypes, a much more pronounced immunoreactivity could be observed in the fibrous septa and the cords. This suggests that the tumor cells are possibly capable of synthesizing growth factors which stimulate fibroblasts to synthesize tenascin. The results indicate that tenascin does not accumulate in the stroma of malignant lymphoid neoplasms with the exclusion of some subtypes of Hodgkin's disease. The distribution of tenascin immunoreactivity in lymphatic tissue is similar to that of the reticular fibers suggesting that the molecules are associated with these structures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

p53 expression in lymphatic malignancies.

AIMS: To investigate the expression of p53 protein in malignant and benign lymphoid tissues. METHODS: Tissue from 42 non-Hodgkin's lymphomas, 10 Hodgkin's lymphomas, three atypical hyperplasias and five benign reactive hyperplasias was studied immunohistochemically for the expression of p53 protein. RESULTS: Of the 42 non-Hodgkin's lymphomas, 13 (31%) were positive for p53 in some of the tumour cells. In two cases the proportion of positive cells was more than 10% and in four cases it was between 1-5%. These six cases consisted of three Burkitt's lymphomas, one immunoblastic lymphoma, one centroblastic diffuse lymphoma and one angioimmunoblastic lymphoma. In seven cases the proportion of p53 positive tumour cells was less than 1%. These cases comprised three centroblastic diffuse, three centroblastic polymorphic diffuse, and one angioimmunoblastic type lymphoma. In three out of 10 (30%) Hodgkin's lymphomas, a proportion of the Reed-Sternberg cells were p53 positive. One of these was a mixed cellular subtype and two nodular sclerosing subtypes. p53 protein was not expressed in the three atypical hyperplasias or the five benign reactive hyperplasias of the lymph nodes. CONCLUSIONS: The presence of p53 positivity in non-Hodgkin's and Hodgkin's lymphomas indicates that mutations of the p53 gene may play a part in the development of these tumours. The concentration of p53 positivity in high grade lymphomas suggests that p53 is involved in the transformation of low grade lymphomas to more aggressive types. Because no p53 positivity was observed in benign lesions of the lymph nodes, positive p53 immunohistochemical staining in a lymphoid lesion suggests malignancy.

Hodgkin Disease↗

Abnormal CD4:CD8 ratios and delayed germinal center reconstitution in lymph nodes of human graft recipients with graft-versus-host disease (GVHD): an immunohistological study.

We searched for evidence that immunodeficiency in graft-versus-host disease (GVHD) is in part due to alloimmune damage to lymph nodes. We used immunoperoxidase techniques to stain T-cell subsets, pan-B cells, and follicular dendritic reticular cells (FDRC) in frozen sections of lymph nodes from 80 marrow graft recipients (56 with GVHD, 11 autografts, and 13 allografts without GVHD). We found that 46% of the GVHD patients had reversed CD4:CD8 ratios and only 13% of non-GVHD patients had such disturbed ratios (p = 0.006). Pan-B (CD22) cell labeling was present in the follicular regions of 73% of patients without GVHD and only 53% of patients with GVHD (p = 0.05). Focal FDRC staining was geographically concordant with clusters of B cells in 88% of cases (p less than 10(-7)). These data confirm that disturbed intranodal CD4:CD8 ratios are present more frequently in GVHD patients than in non-GVHD patients or in autografted patients. They suggest more delayed follicular B-cell reconstitution in GVHD patients. They show an extremely tight association of FDRC with clusters of B cells in the recovering lymph node, as in the developing fetal node. We hypothesize that the lack of follicular dendritic cells may contribute to dysfunctional B-cell maturation by ablating orderly antigen presentation and clonal expansion in the lymph node cortex.

B-Lymphocytes↗

Effect of biliary tract procedures on duodenogastric reflux and the gastric mucosa.

The effect of alterations in the biliary tract on the gastric milieu was evaluated in gallstone disease and after cholecystectomy or biliary fenestration and compared with a control group. Endoscopic bile reflux was often found in gallstone patients (67%) and almost always after cholecystectomy (89%). Gastric bile acid concentrations were greater in the gallstone patients than in the control patients, were higher still after cholecystectomy, and were highest after biliary fenestration. The pH of the gastric fluid was more alkaline in the cholecystectomized groups. Lysolecithin concentrations were generally low and did not differ between the groups, nor was there any difference in scintigraphic reflux between the groups. Endoscopic erythematous gastritis correlated with the grade of bile reflux and was a common finding after biliary tract procedures. There were no consistent histologic findings associated with duodenogastric reflux. Helicobacter pylori colonization rates were similar in the various patient groups and were not affected by the reflux grade.

Aged↗

DNA ploidy in pancreatic neuroendocrine tumors.

The nuclear DNA content of 17 pancreatic neuroendocrine tumors was measured from paraffin-embedded tissue with flow cytometry. The tumors were classified by immunostaining with antisera for synaptophysin, insulin, gastrin, glucagon, pancreatic polypeptide, somatostatin, and vasoactive intestinal polypeptide. Eight (47%) of the 17 tumors were aneuploid, and two (12%) were multiploid (had two aneuploid stemlines of cells). Seven of the eight insulinomas, one of the four gastrinomas, and two of the four nonspecified neuroendocrine tumors had an abnormal nuclear DNA content. The DNA indices of the aneuploid and multiploid cases ranged from 1.13 to 1.93, and three cases had a DNA index greater than 1.50. During the follow-up for up to 16 years (mean, 7 years), one patient with diploid nonspecified tumor died of the disease, another patient with a multiploid gastrinoma had metastatic disease develop, and a third patient with a multiploid nonspecified tumor was alive with the disease. The authors conclude that many neuroendocrine tumors of the pancreas have an abnormal nuclear DNA content as measured by DNA flow cytometry. DNA multiploid pancreatic neuroendocrine tumors may be associated with a less favorable clinical course, but this needs to be confirmed in additional studies.

Adult↗

Effective clinical response to long term octreotide treatment, with reduced serum concentrations of growth hormone, insulin-like growth factor-I, and the amino-terminal propeptide of type III procollagen in acromegaly.

Ten patients with active acromegaly, six with a poor response to previous therapies and four newly diagnosed, were treated with the long-acting somatostatin analog octreotide (Sandostatin; 200-500 micrograms/day, sc, twice or three times daily) for 6-15 months. There was rapid clinical improvement in all patients. The mean daily serum GH concentration was reduced by 64% and was normalized (all GH values less than 2 micrograms/L) in three patients. Serum insulin-like growth factor-I (IGF-I) concentrations were lowered by 40% and were normalized in eight patients. Serum concentrations of the amino-terminal propeptide of type III procollagen (PIIINP), an index of tissue collagen metabolism, were reduced by 40% and were normalized in all patients with initially elevated values. There was a statistically significant positive correlation between the mean serum GH and IGF-I levels (r = 0.47; P less than 0.001) as well as between serum GH and PIIINP levels (r = 0.34; P less than 0.05) and between serum IGF-I and PIIINP (r = 0.50; P less than 0.001). The effects of octreotide on pituitary tumor size and pathology were evaluated in one patient. The therapy did not seem to be associated with significant changes in sellar computed tomographic scans or light microscopic findings. The drug was generally well tolerated. However, indications of significant hepato-biliary dysfunction were noted in one patient after 5 months of therapy. This was reversible upon discontinuation of therapy and did not occur later during the rechallenge with a lower dose of the drug. However, there was probably newly formed cholelithiasis in four patients during the therapy. Our study suggests that octreotide is an effective and relatively safe new approach for treating active acromegaly. Further studies are needed to investigate long term effects on the hepatobiliary system.

Acromegaly↗

A malignant Leydig cell tumour associated with testicular trauma and prostatic carcinoma.

A case of metastatic Leydig cell carcinoma without sex hormone overproduction is reported. The patient had had a prior testicular contusion trauma on the same side after which the testicle had been swollen and firm. The possible aetiological role of extreme trauma is discussed. Radical orchidectomy is recommended for large tumours because of the difficulty in predicting malignant potential, and routine follow-up with retroperitoneal ultrasound scanning for 10 years in all cases.

Aged↗

Flow cytometric DNA analysis of 199 histologically favourable or unfavourable non-Hodgkin lymphomas.

We have studied the nuclear DNA content of histologically favourable (n = 82) or unfavourable (n = 117) non-Hodgkin lymphomas (NHLs) diagnosed between 1957 and 1978 in the Tampere University Central Hospital. The DNA analysis was done by applying a trypsin digestion method to archival tumour samples. DNA aneuploidy was seen in 40 per cent of the unfavourable cases and in 10 per cent of the favourable cases, but varied considerably between different histological subtypes. The unfavourable cases showed high proliferative activity (S-phase fraction, SPF), while considerable variation in the SPF among the favourable NHLs was noted. Among the unfavourable NHLs, cases with DNA-aneuploid tumours had significantly (P less than 0.01) worse prognosis than stage and treatment matched cases with DNA-diploid tumours. In general, survival of the patients who had high SPF tumours was significantly lower compared with patients with low SPF tumours (P less than 0.01). However, SPF was not related to the prognosis in the unfavourable NHLs. We conclude that the flow cytometric DNA analysis revealed characteristic features in the favourable and unfavourable NHLs and may be useful in predicting the clinical outcome of patients.

Adult↗

Quantity of nuclear DNA in malignancies and benign lymphadenopathies associated with Epstein-Barr virus.

The quantity of nuclear DNA in 90 tumours with a strong probability of being associated with Epstein-Barr virus (EBV) (11 cases with nasopharyngeal carcinomas, seven cases of endemic and 26 of non-endemic Burkitt's lymphoma, and 46 cases of Hodgkin's disease) were analysed by flow cytometry. Twenty three cases with benign lymphadenopathies were analysed in a similar way. Except for endemic Burkitt's lymphoma most of the tumours were diploid. Near-diploid aneuploidy (with a DNA index ranging from 1.06 to 1.26) was also found in endemic Burkitt's lymphoma as well as in six non-endemic Burkitt's lymphomas and in eight cases of Hodgkin's disease but was absent in nasopharyngeal carcinomas. Tetraploid aneuploidy was seen in three cases of nasopharyngeal carcinoma. Five of the 23 cases of lymphadenopathy also showed near-diploid DNA, one of which subsequently developed into a non-Hodgkin's lymphoma. It is concluded that near-diploid DNA content seems to be associated with the lymphatic origins of the tumours rather than with EBV.

Adolescent↗

Improving the prognostic value of DNA flow cytometry in breast cancer by combining DNA index and S-phase fraction. A proposed classification of DNA histograms in breast cancer.

To optimize the prognostic value of DNA flow cytometry in breast cancer the authors calculated several parameters from the DNA histogram, including the DNA index, the size and number of aneuploid peaks as well as S-phase and G2/M-phase cell cycle fractions. Of these, DNA index and S-phase fraction (SPF) proved to be the most valuable prognostic indices. DNA aneuploidy was associated with a three-fold risk of death as compared to DNA diploidy (P less than 0.0001). The highest risk of death was associated with hypertetraploid (greater than 2.20) DNA index, whereas a tetraploid DNA index (1.80-2.20) was associated with a relatively low risk. The SPF had significant additional prognostic value in both DNA diploid (P = 0.0002) and DNA aneuploid (P = 0.02) tumors. By combining DNA index and SPF the authors defined three types of DNA histograms, which were associated with favorable, intermediate, and poor prognosis of the patients. DNA diploidy together with low (less than 7%) SPF (type I DNA histogram) was associated with very favorable prognosis, whereas DNA aneuploidy with high DNA index (greater than 2.20) or high (greater than 12%) SPF (type III DNA histogram) was related to the worst prognosis with approximately eight-fold relative risk of death. In a Cox multivariate regression analysis the type of DNA histogram was an independent and most powerful prognostic indicator in breast cancer. The other independent factors in the Cox analysis were primary tumor size, nodal status, and progesterone receptor status.

Aged↗

An immunohistochemical study of laminin, type-IV collagen and type-III pN-collagen with relation to reticular fibres in Hodgkin's disease.

The distribution of aminoterminal propeptides of type-III procollagen (indicating the presence of type-III pN-collagen, i.e., type-III collagen molecule with a non-cleaved aminoterminal propeptide), laminin and type-IV collagen was studied by immunohistochemical methods. The results were compared with the distribution of reticular fibres using Gomori's reticulin stain. Lymph nodes from 20 cases of Hodgkin's disease (HD) and 3 spleens affected by nodular sclerosis HD were studied. The reticular fibres stained for all the antigens investigated, the strongest reaction being for pN type-III collagen. Thick fibres stained mainly for type-III pN-collagen, the BM proteins being located in a fragmented rim on the surface. The distribution and composition of fibres was similar in both nodal and extranodal infiltrations. The morphological alterations noted in the fibres comprised (1) compression between nodules in the nodular type of lymphocyte-predominant HD, and (2) fragmentation, present in collections of histiocytes in lymphocyte-predominant HD. BM proteins and type-III pN-collagen were present in the walls of the sinuses and vessels. The marginal sinuses were often partially spared in spite of extracapsular invasion. Our results suggest that laminin, type-IV collagen and type-III pN-collagen are important components of reticular fibres in HD and that the composition of the fibres is similar to that seen in the normal lymph node.

Adult↗