Heat shock protein 70 (HSP70) and complement C4 genotypes in patients with hyperthyroid Graves'' disease.

The genetic polymorphisms of the heat shock protein 70 (HSP70) and complement component C4 were investigated in 90 patients with hyperthyroid Graves' disease and 92 normal control subjects. The 8.5-kb PstI HSP70 allele was strongly associated with Graves' disease when compared with controls (P less than 0.001). The presence of the 8.5-kb PstI HSP70 allele was strongly associated with a deletion of the C4A gene in both patients and controls (P less than 0.0003 and P less than 0.00005 respectively). However, in the absence of C4A gene deletion, the frequency of the 8.5-kb PstI HSP70 allele was still significantly higher in patients when compared with controls (P less than 0.04). These results suggest that the HSP70 locus may have an immunological role to play in autoimmune hyperthyroid Graves' disease.     

Surgical pathology of pulmonary thromboendarterectomy: a study of 54 cases from 1990 to 2001

Thromboendarterectomy is performed to treat chronic thromboembolic pulmonary hypertension with obstruction of main, lobar, or segmental pulmonary arteries. The present study evaluated surgical specimens removed between 1990 and 2001. Medical histories and microscopic slides were reviewed in each case. Study slides were stained with hematoxylin and eosin and Verhoeff-van Gieson and evaluated for thrombus, collagen, elastin, atherosclerosis, hemosiderin, calcification, and inflammation. The study group comprised 54 patients (30 women and 24 men), ranging in age from 33 to 77 years (mean, 58 years). Clinically, 28 (52%) had a history of deep leg vein thrombosis and 42 (78%) had a history of pulmonary embolism; 24 (44%) had both events. Coagulation abnormalities were documented in 15 (28%); autoimmune or hematologic disorders, in 8 (15%). Pulmonary thromboendarterectomy was bilateral in 52 patients (96%) and right-sided in 2. Six patients also had obstructions resected from the main pulmonary arteries. Obstruction limited to segmental arteries occurred only in women. Grossly, right-sided specimens were larger than left-sided ones (P = 0.003). Microscopically, ages of thrombi were uniform in 72% and variable in 28%. Intima was thickened in all patients and consisted of collagen (100%), elastin (67%), hemosiderin (56%), inflammation (53%), atherosclerosis (32%), and calcification (15%). We determined that pulmonary thromboendarterectomy was performed most often in middle-aged and elderly patients with a history of deep venous thrombosis or pulmonary embolism. Less than 50% of the patients had an identifiable coagulation, autoimmune, or hematologic abnormality. Most patients had bilateral disease and resections. Right-sided specimens were significantly larger than left-sided specimens, and lower lobe involvement was more common than involvement elsewhere. Resected tissues most commonly exhibited old organized thrombus.     

Steroid hormone receptors in human salivary gland tumours.

Major salivary gland tumours were studied for the presence of hormone receptors for oestrogen and progesterone. Of the eight salivary gland tumours exhibiting varied histology, none showed high affinity receptors for oestrogen or progesterone. Salivary tissue from four patients with non-neoplastic salivary gland disease was also studied and found not to contain high affinity receptor sites. The absence of hormone receptors in these glands suggests that such tumours are not dependent on endocrine function.     

New families of adhesion molecules play a vital role in platelet functions

Adhesion molecules play a crucial part in cell-matrix and in cell-cell interactions. These interactions, which are essential to the body's defense processes, involve adhesion molecules belonging to different families: integrins, immunoglobulins and selectins. Integrins are expressed by a large number of tissues, whereas other adhesion molecule families are restricted to a small number of cell types. A recent symposium dealt with the recruitment of circulating platelets at specific sites, their adhesion to extracellular matrix components and their activation by agonists leading to aggregation or attachment to other cells. These events, supporting hemostasis and thrombosis, involve integrins, selectins and other adhesion molecules. This report focuses on newly reported integrins (GPIa, GPIc, GPIIa), selectins (GMP-140) and GPIIIb, previously known as 'minor' surface oriented platelet glycoproteins. Major membrane glycoproteins such as GPIIb-IIIa (an integrin) and GPIb, which also play a vital role in platelet functions, have been extensively reviewed elsewhere.     

Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1

The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X- linked RP (XLRP), has been mapped previously to a chromosome interval of less than 1000 kbp between the DXS1110 marker and the OTC locus at Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization (YRH)', we have recently identified a small XLRP associated microdeletion in this interval, as well as several putative exons including the 3' end of a gene that was truncated by the deletion. cDNA library screening and sequencing of a cosmid centromeric to the deletion has now enabled us to identify numerous additional exons and to detect several point mutations in patients with XLRP. The predicted gene product shows homology to RCC1, the guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our findings suggest that we have cloned the long-sought RP3 gene, and that it may encode the GEF of a retina-specific GTP-binding protein.      

High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes

As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.      

p75(NTR) gene and suicide attempts in young adults with a history of childhood-onset mood disorder.

Recently, evidence has accumulated for the role of neurotrophic processes in mood disorders. Neurotrophins operate on receptors, one of which is the p75 neurotrophin receptor (p75(NTR)). We examined three p75(NTR) markers at the p75(NTR) gene, including a missense polymorphism that changes serine to leucine (S205L), for association with suicide attempt (SA) in 203 childhood-onset mood disorder (COMD) cases. There was no difference between COMD suicide attempters and COMD non-attempters with logistic regression models for any of the three markers. We also compared the three polymorphisms between 192 COMD cases and 192 matched healthy controls and found no significant differences between COMD and healthy controls. Our results do not support an association of the p75(NTR) S205L polymorphism with risk for COMD or SA in COMD.     

Disseminated toxoplasmosis in cardiac transplantation.

The first case of disseminated toxoplasmosis following cardiac transplantation in the UK is described, with details of Toxoplasma antibody tests made on other cardiac transplant patients. Sixteen of 40 (39%) of recipients had Toxoplasma antibody before operation. Eleven of 30 (37%) of donors had Toxoplasma antibody. The were four occasions when a negative recipient received a heart from a positive donor. Three survived the immediate postoperative period and two became infected with toxoplasmosis. The implications of this are discussed. Disseminated toxoplasmosis appears much more often when heart muscle from a dye test positive donor is given to a dye test negative recipient. Antibiotic therapy is limited by the fact that the antitoxoplasma drugs available are static in their effect, and need to be given for prolonged periods postoperatively.     

Depletion of neuropeptides during wound healing in rat skin

The peptides substance P, calcitonin gene-related peptide and somatostatin are present in nerve fibres in mammalian, including human, skin. There is evidence that in addition to having a putative neurotransmitter role, they may be trophic agents: a study was therefore undertaken of peptide changes during wound healing in rat skin. A significant depletion of the neuropeptides was found in the region of the wound within two days, and this persisted for two weeks. A smaller and delayed depletion also occurred in intact skin of the same dermatome, but not in an adjacent dermatome.