Biochemical polymorphism and the 2,3-diphosphoglycerate in the sheep red blood cells

Summary There was no significant difference in the level of 2,3-DPG in the red blood cells of sheep of different haemoglobin types (Hb A and Hb B) or potassium types (HK and LK). However, low glutathione (GSH^L) sheep had significantly higher (p<0.01) level of 2,3-DPG in their red blood cells than high glutathione (GSH^H) sheep. There was also significant effect of interactions between glutathione, haemoglobin and potassium types (p<0.05) and glutathione and haemoglobin types (p<0.01) on red cell 2,3-DPG levels.     

Immunological and morphological consequences of vasectomy in the rabbit

Summary Cell-mediated immunity to spermatozoa was detected in vitro 6–18 months after vasectomy in the rabbit. The autoimmunity was accompanied by aspermatogenic orchitis in the testes and epididymides.Acknowledgments. We acknowledge the financial support of the Australian Research Grants Committee and the Australian and Kenyan Governments for support through the Australian Development Assistance Bureau.     

Loss-of-function mutations in the cathepsin C gene result in periodontal disease and palmoplantar keratosis

Papillon-Lefèvre syndrome, or keratosis palmoplantaris with periodontopathia (PLS, MIM 245000), is an autosomal recessive disorder that is mainly ascertained by dentists because of the severe periodontitis that afflicts patients. Both the deciduous and permanent dentitions are affected, resulting in premature tooth loss. Palmoplantar keratosis, varying from mild psoriasiform scaly skin to overt hyperkeratosis, typically develops within the first three years of life. Keratosis also affects other sites such as elbows and knees. Most PLS patients display both periodontitis and hyperkeratosis. Some patients have only palmoplantar keratosis or periodontitis, and in rare individuals the periodontitis is mild and of late onset. The PLS locus has been mapped to chromosome 11q14-q21 (refs 7, 8, 9). Using homozygosity mapping in eight small consanguineous families, we have narrowed the candidate region to a 1.2-cM interval between D11S4082 and D11S931. The gene (CTSC) encoding the lysosomal protease cathepsin C (or dipeptidyl aminopeptidase I) lies within this interval. We defined the genomic structure of CTSC and found mutations in all eight families. In two of these families we used a functional assay to demonstrate an almost total loss of cathepsin C activity in PLS patients and reduced activity in obligate carriers.     

A two-solar-mass neutron star measured using Shapiro delay

Neutron stars are composed of the densest form of matter known to exist in our Universe, the composition and properties of which are still theoretically uncertain. Measurements of the masses or radii of these objects can strongly constrain the neutron star matter equation of state and rule out theoretical models of their composition. The observed range of neutron star masses, however, has hitherto been too narrow to rule out many predictions of 'exotic' non-nucleonic components. The Shapiro delay is a general-relativistic increase in light travel time through the curved space-time near a massive body. For highly inclined (nearly edge-on) binary millisecond radio pulsar systems, this effect allows us to infer the masses of both the neutron star and its binary companion to high precision. Here we present radio timing observations of the binary millisecond pulsar J1614-2230 that show a strong Shapiro delay signature. We calculate the pulsar mass to be (1.97?±?0.04)M(⊙), which rules out almost all currently proposed hyperon or boson condensate equations of state (M(⊙), solar mass). Quark matter can support a star this massive only if the quarks are strongly interacting and are therefore not 'free' quarks.