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T Pettersson

Publications and source records attributed to T Pettersson.

At least 19 recordsLinked to original sources
PubMed1992

Production, purification and characterization of recombinant human interferon gamma.

An essentially three-step chromatographic purification procedure, i.e., ion-exchange, immobilized metal ion affinity and size-exclusion chromatography, is described for the purification to homogeneity of recombinant human interferon-gamma (rhIFN-gamma) from the inclusion bodies produced in genetically transformed Escherichia coli cells. Batchwise adsorption of the cloudy solution of renatured rhIFN-gamma obviated the need for high-speed centrifugation to clarify the suspension. This step effectively removed about 70% of extraneous protein impurities. The established purification process is reproducible and leads to a total recovery of 32%. Pilot-scale processing of E. coli cells grown in a 30-l fermentor gave about 70 mg of a homogeneous preparation of rhIFN-gamma. The specific biological activity of purified rhIFN-gamma is ca. 3.4 x 10(7) I.U./mg protein, which is comparable to that of its natural counterpart. It is basic protein (pI greater than pH 9) with a monomer relative molecular mass of 15,000. It behaves, however, as a dimer on size-exclusion chromatography. Its partial NH2-terminal sequence is identical with that established for the rhIFN-gamma. However, its amino acid composition and its relative molecular mass (15,067 as determined by electrospray mass spectrometry) indicate that the purified protein is a truncated form lacking fifteen amino acid residues from its carboxyl-terminal side. This modification does not seem to have any adverse effect on its biological potency. The levels of DNA, bacterial endotoxins and Ni(II) ions in the final product were determined.

Amino Acid Sequence↗
PubMed1992

Granzyme A-immunoreactive cells in synovial fluid in reactive and rheumatoid arthritis.

Perforin and granzyme A co-localize in the cytotoxic granules of killer cells like cytotoxic T lymphocytes (CTL). Perforin is the cytolytic pore-forming protein, whereas the function of the homodimeric serine protease granzyme A and other members of the granzyme family is still unclear. Granzyme A-immunoreactive cells formed 8 +/- 2% of the resting peripheral blood lymphocytes of healthy individuals. In contrast, granzyme A-positive cells formed 15% of peripheral blood mononuclear cells in patients with reactive or rheumatoid arthritis. However, 29 +/- 4% (p < 0.05 compared to normal peripheral blood) and 25 +/- 4% (p < 0.05) of all lymphocytes in synovial fluid in reactive and rheumatoid arthritis, respectively, were granzyme A-positive. This suggests involvement of cell-mediated cytolytic mechanisms in the articular pathogenic mechanisms. This involvement, however, does not differentiate between reactive and rheumatoid arthritis.

Adult↗
PubMed1992

Increased CKMB (mass concentration) in patients without traditional evidence of acute myocardial infarction. A risk indicator of coronary death.

A study of 102 patients consecutively admitted to a coronary care unit (CCU) investigated the clinical usefulness of three different immunoenzymometrical CKMB methods: NovoClone CK-MB, ICON QSR CKMB and IMx CK-MB. Blood samples were drawn on admission and then every 6 h for 48 h. The three different methods correlated very well (r = 0.93-0.96). With discrimination levels of 10 micrograms.l-1 for NovoClone CK-MB and 5 micrograms.l-1 for the other two methods, a sensitivity of 1.0 and a still acceptable specificity (> 0.81) were achieved. In the group of patients (n = 53) with suspicion of acute myocardial infarction (AMI) but with no standard criteria for AMI, 14 patients were identified with small but significant increase of serum CKMB (mass concentration) and an increased CKMB (mass concentration)/CK ratio. During a 4 year follow-up nine out of these 14 patients died within 2 years, the majority being coronary deaths, as compared to only two out of the remaining 39 non-AMI patients with suspicion of AMI but with normal CKMB values (chi 2 = 18.47, P < 0.001). The finding of such a high mortality rate among patients with increased CKMB (mass concentration) has an important prognostic value even in patients without standard criteria for AMI.

Adult↗
PubMed1992

Cytophagic histiocytic panniculitis: a report of four cases.

Four patients presented with a clinical picture of spiking fever, erythematous nodular subcutaneous skin lesions, anaemia and leucopenia. Inconstant features were weight loss (3/4), splenomegaly (3/4), thrombocytopenia (3/4), raised liver enzymes (3/4), hepatomegaly (2/4) and serosal effusions (2/4). The histopathological findings of lobular histiocytic panniculitis with 'bean-bag' cells were characteristic of cytophagic histiocytic panniculitis (CHP). No infectious agent could be detected, and there was no histological evidence of malignant neoplasia. Unlike most previously described patients with CHP, three of our four patients responded to treatment with immunosuppressive or cytostatic drugs.

Adipose Tissue↗
PubMed1992

Autosomal dominant 'Mediterranean fever' in a Finnish family.

A 23-year-old Finnish man was examined because of an 8-year history of recurrent bouts of fever and abdominal pain. His father had been repeatedly investigated because of similar episodes since he was 24 years old, and one of the father's sisters was reported to have had recurrent periods of fever. The clinical features closely resembled those of familial Mediterranean fever (FMF), a syndrome rarely described in families of European descent. Unlike typical FMF, which is inherited as an autosomal recessive trait, the mode of inheritance of the syndrome in our family may be regarded as dominant. During a recent attack, serum concentrations of interleukin-1-beta, interleukin-6 and acute phase reactants, including serum amyloid A protein, were high. No signs of amyloidosis were detected in our patients.

Adult↗
PubMed1992

Immunoreactive interleukin-6 in serum of patients with B-lymphoproliferative diseases.

Serum immunoreactive interleukin-6 (ir-IL-6) concentration was measured by radioimmunoassay in nine patients with chronic lymphocytic leukaemia (CLL), 16 patients with multiple myeloma (MM), 12 patients with monoclonal gammapathy of undetermined significance (MGUS), 22 patients with primary Sjögren's syndrome (SS), and in 32 control subjects. Measurable quantities of ir-IL-6 were detected in every sample studied. Patients with MGUS and SS had significantly higher serum ir-IL-6 (mean +/- SD) concentrations (337 +/- 92 ng l-1 and 299 +/- 100 ng l-1, respectively) than controls (92 +/- 77 ng l-1) and patients with CLL and MM (120 +/- 32 ng l-1 and 113 +/- 58 ng l-1, respectively). Longitudinal studies of ir-IL-6 concentration in a few patients with MM showed a decrease before remission and an increase prior to relapse, but no consistent pattern was detected. In conclusion, we found that serum ir-IL-6 levels are higher in patients with benign hypergammaglobulinaemic states than in patients with malignant neoplastic B-cell disorders.

Adult↗
PubMed1992

Increased risk of cancer in patients with systemic lupus erythematosus.

To evaluate the risk of cancer in patients with systemic lupus erythematosus (SLE) a series of 205 consecutive patients (182 women and 23 men) were followed up for cancer through the files of the Finnish Cancer Registry. The follow up consisted of a total of 2340 person years. Fifteen cancers were diagnosed against 5.7 expected (relative risk (RR) 2.6, 95% confidence interval (CI) 1.5 to 4.4). Among the women there were four non-Hodgkin's lymphomas against 0.09 expected (RR 44, CI 11.9 to 111) and two soft tissue sarcomas against 0.04 expected (RR 49, CI 6.0 to 177). When evaluated by a case control study previous treatment with cytostatic drugs showed no influence on the occurrence of cancer in this series of patients with SLE.

Adult↗
PubMed1991

Diagnostic value of cerebrospinal fluid adenosine deaminase determination.

We measured the activity of adenosine deaminase (ADA) in the cerebrospinal fluid of 3 patients with tuberculous meningitis, 38 with viral meningitis, 15 with bacterial meningitis, 5 with malignant lymphoma, 11 with cerebrovascular diseases and 13 with miscellaneous neurological disorders. The highest ADA activities were observed in patients with tuberculous meningitis (median 21.3 U/l, range 20.0-23.0) and lymphoma (13.0 U/l, range 4.0-25.0). The sensitivity of the test for diagnosing tuberculous meningitis was 100% and the specificity 99% when a cut-off value of 20.0 U/l was used. We conclude that determination of ADA in cerebrospinal fluid is useful for the diagnosis of tuberculous meningitis, but that high activity also can be seen in some other CNS disorders, e.g. lymphoma with meningeal involvement.

Adenosine Deaminase↗
PubMed1990

Spontaneous and in vitro activation of synovial fluid and peripheral blood lymphocytes in rheumatoid arthritis.

Peripheral blood (PB) and synovial fluid (SF) were compared in parallel samples in rheumatoid arthritis (RA). The kinetics of in vitro T-cell activation was assessed in phytohemagglutinin (PHA) stimulated PB or SF mononuclear cell cultures on days 0, 1, 3 and 5. The early lymphocyte activation as assessed by interleukin-2 receptor expression was faster in SF than in PB cell cultures. In particular, IFN-gamma secretion was higher in SF than in PB cell cultures (p less than 0.01). Accordingly, lymphocyte major histocompatibility complex (MHC) locus II antigen expression was higher in SF than in PB cell cultures (53 +/- 7% vs. 21 +/- 5%; p less than 0.01). Our results suggest that lymphocytes, which are particularly effective producers of IFN-gamma when stimulated in vitro are sequestered in the diseased joints in RA.

Adult↗
PubMed1990

Concentration of tumor-associated trypsin inhibitor (TATI) in pleural effusions.

We measured the concentration of tumor-associated trypsin inhibitor (TATI) in plasma and pleural fluid of 84 patients with pleural effusions of various causes. We observed elevated (greater than 30 micrograms/L) TATI levels in pleural fluid in 45 percent of patients with pleural effusion associated with malignant disease and in 15 percent of patients with benign disease. Similar results were obtained for TATI in plasma. The concentration of TATI in pleural fluid closely parallelled that in plasma. In patients with renal insufficiency and in patients with biliary obstruction, the TATI levels were elevated both in plasma and pleural fluid. A positive correlation was seen between the concentration of TATI and the activity of alkaline phosphatase in plasma. The results show that simultaneous determination of TATI in plasma and pleural fluid improves the diagnosis of cancer only marginally. Our results also support the hypothesis that elevated TATI levels may reflect an acute phase reaction caused by inflammatory disease or tissue destruction associated with cancer not only in inflammatory conditions, but also in malignant disease where the tumor itself is not producing TATI.

Biomarkers, Tumor↗
PubMed1989

Thyroxine transport and distribution in Nagase analbuminemic rats.

The postulate that thyroxine (T4) in plasma enters tissues by protein-mediated transport or enhanced dissociation from plasma-binding proteins leads to the conclusion that almost all T4 uptake by tissues in the rat occurs via the pool of albumin-bound T4 (Pardridge, W. M., B. N. Premachandra, and G. Fierer. 1985. Am. J. Physiol. 248:G545-G550). To directly test this postulate, and to test more generally whether albumin might play a special role in T4 transport in the rat, we performed in vivo kinetics studies in six Nagase analbuminemic rats and in six control rats, all of whom had similar serum T4 concentrations and percent free T4 values. Evaluation of the plasma disappearance curves of simultaneously injected 125I-T4 and 131I-albumin indicated that the flux of T4 from the extracellular compartment into the rapidly exchangeable intracellular compartment was similar in the analbuminemic rats (51 +/- 21 ng/min, mean +/- SD) and in the control rats (54 +/- 15 ng/min), as was the size of the rapidly exchangeable intracellular pool of T4 (1.13 +/- 0.53 vs. 1.22 +/- 0.36 micrograms). This latter finding was confirmed by direct analysis of tissue samples (liver, kidney, and brain). We also performed in vitro kinetics studies using the isolated perfused rat liver. The single-pass fractional extraction by normal rat liver of T4 in pooled analbuminemic rat serum was indistinguishable from that of T4 in pooled control rat serum (10.9 +/- 3.3%, n = 3, vs. 11.4 +/- 3.4%). When greater than 98% of the albumin was removed from normal rat serum by chromatography with Affi-Gel blue, the single-pass fractional extraction of T4 (measured by a bolus injection method) did not change (16.3 +/- 2.1%, n = 5, vs. 15.2 +/- 2.5%). These data provide the first valid experimental test of the enhanced dissociation hypothesis and indicate that there is no special, substantive role for albumin in T4 transport in the rat.

Animals↗
PubMed1989

Transthyretin immunoreactivity in human and porcine liver, choroid plexus, and pancreatic islets.

We examined transthyretin immunoreactivity (TTR-IR) in human and porcine liver, choroid plexus, and pancreatic islets with both polyclonal and monoclonal antibodies to TTR. The specificity of the immunoreactions and the effects of various fixatives were tested in immunohistochemical and dot-blot systems. B-5 fixative (mercuric chloride and sodium acetate in formalin) was the best immunopreservative. In both species, the TTR-IR in choroid plexus epithelial cells was strong and was much greater than that in hepatocytes. Glucagon cells in pancreatic islets were also strongly TTR immunoreactive. Insulin cells were slightly TTR immunoreactive in human but strongly so in porcine pancreas. The finding of TTR-IR in normal islets explains the presence of TTR-IR in human endocrine pancreatic tumors, notably glucagonomas and malignant insulinomas.

Animals↗
PubMed1989

Tobacco smoke chemistry. 2. Alkyl and alkenyl substituted guaiacols found in cigarette smoke condensate.

A series of alkyl and alkenyl substituted guaiacols, which comprise a group of biologically and organoleptically active compounds, have been synthesized. Mass spectra and GC retention times for these have been recorded and compared with those obtained for constituents of a weakly acidic fraction of smoke condensate derived from American blend type cigarettes. On the basis of these results, 25 guaiacols have been identified, 18 of which have not been detected in tobacco smoke condensate previously.

Gas Chromatography-Mass Spectrometry↗