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R L Pilgrim

Publications and source records attributed to R L Pilgrim.

7 recordsLinked to original sources
PubMed1999

Detecting APC-resistant factor V: a functional method without plasma dilution.

A method for detecting activated protein C (APC)-resistant factor V, especially factor V Leiden, is described, which uses reagents containing two unfractionated snake venoms. The procedure can be used for testing plasma samples from patients receiving oral anticoagulant therapy, heparin therapy and patients with lupus anticoagulant, and does not require the use of factor-V-deficient plasma. The sample plasma is first incubated with dilute venom from Agkistrodon contortrix contortrix (Southern Copperhead) which activates the endogenous protein C and then a dilute Russell's viper venom time test is performed. In individuals with APC-resistant factor V, especially factor V Leiden, a marginal prolongation of dilute Russell's viper venom time was noted [1.14 +/- 0.14 s (n = 16)]. Non-carriers were easily discriminated in each patient group, with a prolongation of 2.69 +/- 0.30 s for normal blood donors (n = 127), 2.61 +/- 0.38 s for patients taking oral anticoagulants (n = 102), 2.41 +/- 0.45 s for patients taking heparin (n = 96), and 2.38 +/- 0.41 s for patients with lupus anticoagulant (n = 22). Patients taking oral anticoagulants with moderate prolongation (between 1.5- and 2.0-fold) may have low levels of functional protein C and this might additionally indicate a subgroup of such patients at higher than normal thrombotic risk.

Activated Protein C Resistance↗
PubMed1998

Larvae of the genus Notiopsylla (Siphonaptera: Pygiopsyllidae) with a key to their identification.

Larvae of the Southern Hemisphere bird flea genus Notiopsylla Jordan & Rothschild are characterized by a combination of a unidentate mandible, long dorsal trunk setae, a profusion of ventral trunk setae, and a lack of differentiation of the anal circlet into distinct anal comb and series of ventro-lateral setae. The 3rd instar of N. corynetes Smit is described in detail. Descriptions of the 1st and 2nd instars, and the 3 instars of the 3 other species are briefly described by comparison. A key to separate the 4 species is presented; separation of the 2 subspecies of each of N. kerguelensis (Taschenberg) and of N. enciari Smit is based on geographical and host association criteria. The species N. corynetes, N. kerguelensis, N. enciari, and N. peregrinus Smit represent successively derived stages in the evolution of the larvae of Notiopsylla as evidenced by increasing numbers of ventral trunk setae, and by increasing complexity of the antennal shaft sense organ and of the arrangement of the antennal mound papillae. Multiple infestations of some host species by several taxa of Notiopsylla are attributable to the isolation of the birds' breeding colonies on separate islands. A new locality record for N. e. enciari Smit, and a new host record for N. k. tenuata Smit, are given. Distribution data are given for associated material of Parapsyllus Enderlein, and a key is provided to separate the larvae of the 2 genera.

Animals↗
PubMed1993

Increased expression of platelet IgG Fc receptors in immune heparin-induced thrombocytopenia.

Our previous finding that heparin-dependent antibodies in heparin-induced thrombocytopenia (HIT) bind to platelets via platelet IgG Fc receptors (FcRs) prompted this study. Platelet FcRs in 16 patients with HIT, 23 control patients, and 42 normal subjects were studied. Patients with HIT had substantially increased platelet FcRs during the acute illness. Those who suffered serious thrombotic complications or died shortly after diagnosis had significantly more FcRs per platelet than those with milder disease. Consistent with their increased FcRs, platelets of patients with HIT showed increased aggregation reactivity to aggregated IgG and heparin-dependent antibodies. Platelet FcRs in patients with HIT remained elevated for 1 to 3 months after the acute illness then stabilized to a mean value not significantly different from either control group. The increased expression of FcRs on HIT platelets and their increased reactivity to heparin-dependent antibodies may contribute to the pathogenesis of thrombocytopenia and thrombosis in HIT.

Aged↗
PubMed1992

Preparation and examination of flea larvae (Siphonaptera) by light and electron microscopy.

Techniques are described for making permanent slide-mounted specimens. Larvae were thoroughly macerated in KOH to remove soft internal tissue, yielding specimens with enhanced transparency and allowing examination of most of the exoskeleton in a single larva. Fatty material was removed in acetone to eliminate confusion of fat globules with sensilla in the cuticle. The more sclerotized exoskeletal elements, such as integumentary scales and the body sclerites together with their setae and sensilla, were highlighted by staining with carbol fuchsin. Resolution of numbers and arrangement of setae, especially those on the dorsum of the head capsule, in the anal comb, and on the anal mounds, was greatly facilitated by mounting larvae in dorsal orientation. Clearer views of the antennae and mouthparts were obtained, in orientations seldom achieved in whole mounts, by dissecting the head capsule. Discrimination of many taxonomically valuable features was enhanced by the use of phase-contrast microscopy. Interpretation of structures noted in light microscopy was complemented using scanning electron microscopy. The latter allowed differentiation between surface and internal cuticular structures.

Animals↗