Pharmacologic atrial natriuretic peptide reduces human leg capillary filtration

Atrial natriuretic peptide (ANP) is produced and secreted by atrial cells. We measured calf capillary filtration rate with prolonged venous-occlusion plethysmography of supine healthy male subjects during pharmacologic infusion of ANP (48 pmol/kg/min for 15 min; n = 6) and during placebo infusion (n = 7). Results during infusions were compared to prior control measurements. ANP infusion increased plasma [ANP] from 30 +/- 4 to 2,568 +/- 595 pmol/l. Systemic hemoconcentration occurred during ANP infusion: mean hematocrit and plasma colloid osmotic pressure increased 4.6 and 11.3%, respectively, relative to preinfusion baseline values (p < 0.05). Mean calf filtration, however, was significantly reduced from 0.15 to 0.08 ml/100 ml/min with ANP. Heart rate increased 20% with ANP infusion, whereas blood pressure was unchanged. Calf conductance (blood flow/arterial pressure) and venous compliance were unaffected by ANP infusion. Placebo infusion had no effect relative to prior baseline control measurements. Although ANP induced systemic capillary filtration, in the calf, filtration was reduced with ANP. Therefore, pharmacologic ANP infusion enhances capillary filtration from the systemic circulation, perhaps at upper body or splanchnic sites or both, while having the opposite effect in the leg.     

Bleomycin-induced DNA damage and repair in wild-type and thymidine kinase-deficient Friend mouse erythroleukaemia cells

In this paper the DNA damage and repair induced by the radiomimetic agent bleomycin are compared in murine Friend erythroleukaemia wild-type 707 cells and a thymidine kinase-deficient sub-clone BUF. Comparisons are made using results obtained from the alkaline comet assay and unscheduled DNA synthesis experiments. Further analysis to determine the fidelity of bleomycin-induced repair as indicated by mutagenesis to hypoxanthine-phosphoribosyltransferase deficiency was also conducted. Similar sensitivities to bleomycin treatments were observed in the two cell types with the comet assay, while similar levels of dose-dependent excision repair following bleomycin treatments were also detected in unscheduled DNA synthesis experiments. Comet assay and unscheduled DNA synthesis experimental results are in agreement. Survival and induced hypoxanthine-phosphoribosyltransferase mutant frequencies were observed to be unaffected by a thymidine kinase-deficiency in Friend erythroleukaemia cells. The results of this investigation suggest no overall difference in the repair capacities or the repair fidelity of Friend 707 relative to BUF cells following bleomycin treatments.     

Cladribine (2-CDA) given as subcutaneous bolus injections is active in pretreated Waldenstr?m's macroglobulinaemia. Swiss Group for Clinical Cancer Research (SAKK)

Clinical trials with intravenous cladribine infusions in pretreated patients with Waldenstr?m's macroglobulinaemia have shown a response rate of 40%. Our pharmacokinetic studies revealed that the bioavailability of subcutaneous cladribine is complete but that the concentration-time profile is very different from intravenous administration. We designed this phase II multi-institutional trial to study the activity and toxicity of cladribine given as s.c. bolus injections in patients with symptomatic Waldenstr?m's macroglobulinaemia. Between May 1993 and October 1995, 25 patients were accrued: male/female 18/7, median age 65 years (range 44-85). All except one patient had been pretreated with more than one regimen (median 2, range 0-10). 18 patients had progressed under previous therapy and six were in relapse. All patients received cladribine for a total dose of 0.5 mg/kg per cycle as s.c. bolus injections divided over 5 d at > or = 4 week intervals, for a maximum of six cycles. All 25 patients were evaluable for toxicity and response. A total of 67 cycles were administered (median 3 cycles, range 1-6). Overall response rate including disease stabilization which had been progressive under previous therapy was 68%. 10 patients (40%, 95% CI 21-61%) achieved a partial remission. Seven responders had been progressive under previous therapy. Maximum responses were reached no later than the third cycle. Median time to treatment failure and remission duration were 4.4 (range 0.5-33) and 8 months (5-29), respectively. Four patients (16%) suffered from infections W.H.O. grade > or = 2 (pneumonia grade 2, Staphylococcus septicaemia grade 3, viral encephalitis and pneumonia, both grade 4 with complete resolution). No other severe adverse events were observed. Cladribine given as s.c. 5 d bolus injections was found to be active in pretreated Waldenstr?m's macroglobulinaemia and resulted in durable remissions.     

When people with pre-existing disabilities age in place: implications for social work practice

Dental implants are subject to large and highly complex loads of varying magnitude, duration and vector. Bridge performance is closely related to load transmission both at the bone to implant interface and between components within the implant-abutment-bridge cylinder complex. The design of the interface between components within this complex may have a profound influence on the long term function of the implant supported prosthesis. An in vitro evaluation of implants 3.5 mm in diameter, utilizing an internal conical interface has demonstrated increased resistance to bending moments at the fixture-abutment interface (P = 0.00010) and at the abutment-bridge cylinder interface (P < 0.01), when compared to a standard 3.75 mm implant with a hex mediated, butt joint interface. The relatively small values for coefficient of variance measured in both systems would confirm that whilst the size of data is small, it is nonetheless a reliable indication of the relative strength of these implant designs.     

Identification of Bacillus cereus by Fourier transform infrared spectroscopy (FTIR)

The objective of this study was to evaluate the potential of Fourier transform infrared spectroscopy (FTIR) for rapid identification of Bacillus cereus isolates. Ten B. cereus group isolates (comprising B. cereus, Bacillus mycoides, and Bacillus thuringiensis strains), five other Bacillus spp., and five non-Bacillus spp. were used. Two types of media, brain heart infusion (BHI) and Trypticase soy agar (TSA), were tested. The results indicated that all B. cereus group isolates produced characteristic absorbance peaks at wave numbers between 1738 and 1740 cm-1. These peaks were not affected by the growth medium. None of the other bacteria tested showed a similar peak after growth on BHI or TSA. Absorbance peaks between 1800 and 1500 cm-1 of members of the B. cereus group had different shapes and sizes, suggesting that FTIR may be useful for rapid identification of species within the B. cereus group.     

Screening sigmoidoscopy. Factors associated with utilization

Although screening sigmoidoscopy (SS) reduces colorectal cancer mortality, surveys indicate that fewer than half of primary care physicians routinely recommend SS and less than 10% of eligible patients receive this test. The purpose of this study was to explore barriers to compliance with SS through a cross-sectional survey of general medicine patients. Clinician advice, perceived benefit of the test, and having a family member who has had the test are associated with SS, while perceived pain is a barrier to compliance and can negate the positive effects of clinician advice. These factors can be targeted as part of efforts to improve compliance with SS.     

Characterization of a calmodulin-binding transporter from the plasma membrane of barley aleurone

We have used Arabidopsis calmodulin (CaM) covalently coupled to horseradish peroxidase to screen a barley aleurone cDNA expression library for CaM binding proteins. The deduced amino acid sequence of one cDNA obtained by this screen was shown to be a unique protein of 702 amino acids with CaM and cyclic nucleotide binding domains at the carboxyl terminus and high similarity to olfactory and K+ channels. This cDNA was designated HvCBT1 (Hordeum vulgare CaM binding transporter). Hydropathy plots of HvCBT1 showed the presence of six putative transmembrane domains, but sequence alignment indicated a pore domain that was unlike the consensus domains in K+ and olfactory channels. Expression of a subclone of amino acids 482-702 in Escherichia coli generated a peptide that bound CaM. When a fusion protein of HvCBT1 and green fluorescent protein was expressed in barley aleurone protoplasts, fluorescence accumulated in the plasma membrane. Expression of HvCBT1 in the K+ transport deficient Saccharomyces cerevisiae mutant CY162 showed no rescue of the mutant phenotype. However, growth of CY162 expressing HvCBT1 with its pore mutated to GYGD, the consensus sequence of K+ channels, was compromised. We interpret these data as indicating that HvCBT1 acts to interfere with ion transport.     

Design and synthesis of a series of potent and orally bioavailable noncovalent thrombin inhibitors that utilize nonbasic groups in the P1 position

As part of an ongoing effort to prepare therapeutically useful orally active thrombin inhibitors, we have synthesized a series of compounds that utilize nonbasic groups in the P1 position. The work is based on our previously reported lead structure, compound 1, which was discovered via a resin-based approach to varying P1. By minimizing the size and lipophilicity of the P3 group and by incorporating hydrogen-bonding groups on the N-terminus or on the 2-position of the P1 aromatic ring, we have prepared a number of derivatives in this series that exhibit subnanomolar enzyme potency combined with good in vivo antithrombotic and bioavailability profiles. The oxyacetic amide compound 14b exhibited the best overall profile of in vitro and in vivo activity, and crystallographic studies indicate a unique mode of binding in the thrombin active site.     

Long-term analysis of conventional coronary balloon angioplasty and an initial "stent-like" result. The NHLBI PTCA Registry

Researchers examining clinical decision-making often explored the role of the nurse's experience. In these studies, experience was conceptualized as either the time spent in nursing or the knowledge which came from practice. This paper reports on the conceptualization of the nurse's experience emerging from a grounded theory study describing one decision-making process: 'knowing the patient'. Data included in-depth interview text, participant observation fieldnotes, and documents. Data were analysed using the constant comparative method and open, axial and selective coding techniques. In the analysis, the nurse's experience was conceptually defined as 'the application of that learned from previous practice situations'. Three attributes of the nurse's experience emerged. These included a focus on the patient, confidence in practice, and knowledge of antecedents and consequences of similar patient situations. Each aspect enhanced the individualization of nursing interventions. The findings are related to other investigations in nursing and insights for practice are offered.