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L Hammarstrom

Publications and source records attributed to L Hammarstrom.

13 recordsLinked to original sources
PubMed2002

The HLA-DRA*0102 allele: correct nucleotide sequence and associated HLA haplotypes.

Here we correct the nucleotide sequence of a single known variant of the HLA-DRA gene. We show that the coding regions of the HLA-DRA*0101 and HLA-DRA*0102 alleles do not differ at two codons as reported previously, but only in codon 217. Using nucleotide sequencing and DNA samples from individuals homozygous in the major histocompatibility complex, we found that the variant, leucine 217-encoding HLA-DRA*0102 allele was present on the haplotypes HLA-B*0801, DRB1*03011, DQB1*0201 (ancestral haplotype AH8.1), HLA-B*07021, DRB1*15011, DQB1*0602 (AH7.1), HLA-B*1501, DRB1*15011, DQB1*0602, HLA-B*1501, DRB1*1402, DQB1*03011 and HLA-A3, B*07021, DRB1*1301, DQB1*0603. The HLA-DRA*0101 allele coding for valine 217 was observed on the haplotypes HLA-B*5701, DRB1*0701, DQB1*03032 (AH57.1), HLA-DRB1*04011, DQB1*0302, HLA-DRB1*0701, DQB1*0202, and HLA-DRB1*0101, DQB1*05011.

Alleles↗
PubMed2002

Cancer risk among patients with IgA deficiency or common variable immunodeficiency and their relatives: a combined Danish and Swedish study.

The extremely high risk reported for some types of cancer among patients with common variable immunodeficiency (CVID) is based on a limited number of investigations. Therefore, we examined the risks for cancer among 562 Danish and Swedish patients with CVID or IgA deficiency and 2071 relatives in 1958-96. The patients were identified through an Immunodeficiency Register and hospital records, while the relatives were traced through population registers. Cancer incidence was assessed by linkage to the Cancer Registries and compared with that in the general population. Among 386 patients with IgA deficiency, the incidence of cancer was not increased (standardized incidence ratio (SI) = 1.0); but two cases of stomach cancer were found, resulting in a non-significant increase in risk (SIR = 5.4; 95% CI = 0.7-19.5). Among 176 patients with common variable immunodeficiency (CVID), the incidence of cancer at all sites combined was increased (SIR = 1.8; 95% CI = 1.0-2.9), which was due mainly to significant excesses of malignant lymphoma (obs = 4; SIR = 12.1; 95% CI = 3.3-31.0) and of stomach cancer (obs = 3; SIR = 10.3; 95% CI = 2.1-30.2). Among the 626 relatives of patients with CVID, no increase in risk was found for these types of cancer or for cancer overall (obs = 53; SIR = 1.0; 95% CI = 0.8-1.3). Our data show that the risks for malignant lymphoma and stomach cancer among patients with CVID may be lower than reported previously. The absence of an increased risk among relatives suggests that the increased cancer morbidity in patients with CVID is related to the immunodeficiency per se rather than to specific genetic traits shared with their relatives.

Adult↗
PubMed2001

Does 77C-->G in PTPRC modify autoimmune disorders linked to the major histocompatibility locus?

A 77G allele of the gene encoding CD45, also known as the protein tyrosine phosphatase receptor-type C gene (PTPRC), has been associated with multiple sclerosis (MS). Here we determine allele frequencies in large numbers of MS patients, primary immunodeficiencies linked to major histocompatibility complex (MHC) locus and over 1,000 controls to assess whether aberrant splicing of PTPRC caused by the 77C-->G polymorphism results in increased susceptibility to these diseases. Our results show no difference in the frequency of the 77G allele in patients and controls and thus do not support a causative role for the polymorphism in the development of disorders with a strong autoimmune component in etiology.

Animals↗
PubMed1997

Clinical spectrum of X-linked hyper-IgM syndrome.

We report the clinical and immunologic features and outcome in 56 patients with X-linked hyper-IgM syndrome, a disorder caused by mutations in the CD40 ligand gene. Upper and lower respiratory tract infections (the latter frequently caused by Pneumocystis carinii), chronic diarrhea, and liver involvement (both often associated with Cryptosporidium infection) were common. Many patients had chronic neutropenia associated with oral and rectal ulcers. The marked prevalence of infections caused by intracellular pathogens suggests some degree of impairment of cell-mediated immunity. Although lymphocyte counts and in vitro proliferation to mitogens were normal, a defective in vitro proliferative response to antigens was observed in some patients, and additional defects of cell-mediated immunity may be presumed on the basis of current knowledge of CD40-ligand function. All patients received regular infusions of immunoglobulins. Four patients underwent liver transplantation because of sclerosing cholangitis, which relapsed in there. Three patients underwent bone marrow transplantation. Thirteen patients (23%) died of infection and/or liver disease. X-linked hyper-IgM syndrome, once considered a clinical variant of hypogammaglobulinemia, is a severe immunodeficiency with significant cellular involvement and a high mortality rate.

Bone Marrow Transplantation↗
PubMed1996

The hyaline zone and associated root surface changes in experimental orthodontics in rats: a light and scanning electron microscope study.

Light and scanning electron microscopic (SEM) examinations were used to study the hyaline zone and associated root resorption after orthodontic treatment of the upper first molars of rats. The orthodontic treatment consisted of a fixed buccal expansion appliance with an initial force of 250 mN. The animals were divided into nine experimental groups with orthodontic treatment and one control group without orthodontic treatment. Three groups were sacrificed immediately after 1, 3, and 7 days of treatment, and six groups after 7 days of treatment followed by 1, 2, 3, 4, 5, and 6 weeks without treatment. A hyaline zone on the pressure side of the mesial root was identified at the light microscopic level of examination as well as the SEM examination as early as 1 day after the initiation of treatment. In the SEM it was found that on the roots of teeth studied in the first few days after initiation of treatment the hyaline tissue was so firmly attached to the root that it remained in place during the extraction and preparation procedures. After longer treatment periods these hyaline zones were lost at extraction or during the preparation for the SEM examination. The cementum surface under the hyaline zone had a smooth appearance suggesting that the surface had been modified by substances released from the hyaline zone. After 1 week of treatment, resorption in the cementum could be noticed. The resorption extended to the dentine as uncovered dentinal tubuli were found. Formation of reparative cementum started two weeks after treatment. Changes in the cementum surface as well as root resorption cavities could be seen for as long as 6 weeks after the cessation of orthodontic treatment.

Activator Appliances↗
PubMed1994

Hepatitis C virus transmission by intravenous immunoglobulin.

The polymerase chain reaction was used to detect hepatitis C virus infection in patients who had previously been reported to have developed non-A, non-B hepatitis after intravenous immunoglobulin infusion. Of the 33 patients with intravenous immunoglobulin associated non-A, non-B hepatitis studied, HCV RNA could be detected in 15 out of 17 patients (88%) who were HCV RNA negative prior to the development of non-A, non-B hepatitis after implicated intravenous immunoglobulin batches. Similarly, eight out of nine patients (89%) in whom no sample was available for polymerase chain reaction testing prior to intravenous immunoglobulin therapy, had detectable HCV RNA after intravenous immunoglobulin therapy with intravenous immunoglobulin batches implicated in non-A, non-B hepatitis transmission. Two of the three intravenous immunoglobulin preparations implicated in non-A, non-B hepatitis transmissions that were available for polymerase chain reaction testing also had detectable HCV RNA, confirming that hepatitis C virus is the implicated virus in intravenous immunoglobulin-associated non-A, non-B hepatitis.

Hepacivirus↗
PubMed1992

A new concept of the pathogenesis of oral mucous cysts based on a study of 200 cases.

A new hypothesis regarding the pathogenesis of mucous cysts of the oral mucosa is proposed. Based upon a histological study of 188 mucous cysts without epithelial lining out of a total of 200 cysts it is claimed that some cysts may not develop in any of the hitherto described ways as intraductal "mucous retention cysts" or extraductal "mucous extravasation cysts" or from destruction of acini due to the pressure of mucous caused by duct obstruction. It is suggested that some of the cysts, that are found to have developed intraglandularly, are caused by traumatic destruction of a large amount of glandular acini ("parenchymal destruction cysts") and continuous secretion from the remaining acini. The mucus from the disintegrated cells forms a pool, which in time is surrounded by a connective tissue capsule that contains remnants of parenchyma from the affected lobule. This parenchyma degenerates, and eventually the cyst shows the same histological picture as the "mucous extravasation cyst". It is argued that the presence of a feeder duct does not necessarily indicate an extravasation cyst, but may be seen in the "parenchymal destruction cysts" as well. Of the 188 cysts examined 20 (11 per cent) were found to develop intraglandularly, and 36 (19 per cent) were considered probably to have developed intraglandularly.

Adolescent↗
PubMed1976

The effect of ACTH treatment on lymphocyte subpopulations in patients with myasthenia gravis.

Blood lymphocytes were collected before, at various times during treatment and after treatment with ACTH in patients with myasthenia gravis. The relative proportions of thymus-derived (T cells) and bursa-derived (B cells) lymphocytes were determined. Eight of nine patients had a relative increase in B cells, whereas T cells showed a relative decrease. Myasthenic symptoms in these eight patients also were relieved. One patient who was not thymectomized showed virtually no relief in symptoms nor any changes in the relative T and B cell proportions or numbers, indicating a close association between the disease and the thymus-derived immune system.

Adrenocorticotropic Hormone↗