Clinical pharmacology of L-asparaginase was compared by intramuscular and intravenous injections in 12 patients with metastatic cancer or leukemia. Following a single intramuscular injection at the gluteal site of L-asparaginase (10,000 IU/m2), the enzyme appeared in plasma as measured initially at 1 hour, but plateau levels were not reached in plasma until 14 to 24 hours after drug administration. The peak plasma level was 1.12 IU/ml, only one fourth of that seen when L-asparaginase was given intravenously at equal doses. However, the enzyme level decrease in the plasma after intramuscular injections was slower, with a half-life ot 46 hours, compared to 7 to 28 hours for intravenously administered drug. The apparent volume of distribution indicated that the intravenously injected enzyme was mostly distributed in plasma, whereas the intramuscularly injected enzyme yielded a much larger volume of distribution (63 versus 245 ml/kg). In addition, only 19 per cent of the intramuscularly injected dose was in plasma, and the area under the curve (C X t) was only 1/24 that by intravenous route (20 versus 487 IU/ml.hr). No enzyme was measurable in patients' urine samples collected for three days after intramuscular injections of the enzyme, and only a trace (less than 1 per cent) of the enzyme was detected in urine after intravenous administration.

Asparaginase↗

PubMedDate not supplied

Photographic investigation of the human lens and cataract.

Slit-image photography of the anterior segment of the eye can provide important information about the dimensions and optical densities of the refractive structures. It is crucial that the slit-image photograph be in perfect focus and that the slit-beam cut in exactly the same section (along the optic axis) on each occasion. The equipment, principles and techniques which make such precision slit-imagephotography possible are discussed. Clinical and research applications, especially regarding the human lens and cataract, are summarized.

Adolescent↗

PubMedDate not supplied

The solid phase radioimmunoassay technique for hepatitis B (surface) antigen: effects of progressive modification.

Serum specimens submitted for confirmation of hepatitis B antigen (HBsAg) reactivity were tested by counterelectrophoresis (CEP) and by three modifications of the solid phase radioimmunoassay "sandwich" technique (SPRIA). In addition, the specificity of each reaction was determined for two of the SPRIA test methods. One hundred seventy-five of the 688 specimens were reactive by all techniques and a further 60 ere specifically reactive by two of modifications of SPRIA. An additional five specimens were positive by a third SPRIA modification. The primary SPRIA technique, using a homologous guinea pig antibody sandwich, detected 184 nonspecific reactive samples. With the same test done at 45C with a reduced incubation time, there were only 37 nonspecific reactive samples. None of the nonspecific samples was detected when the SPRIA technique used a heterologous guinea pig-human antibody sandwich. The results provide a basis for estimating the effectiveness of the SPRIA technique for HBsAg testing.

Animals↗

PubMedDate not supplied

Image acquisition context: procedure description attributes for clinically relevant indexing and selective retrieval of biomedical images.

OBJECTIVE: To support clinically relevant indexing of biomedical images and image-related information based on the attributes of image acquisition procedures and the judgments (observations) expressed by observers in the process of image interpretation. DESIGN: The authors introduce the notion of "image acquisition context," the set of attributes that describe image acquisition procedures, and present a standards-based strategy for utilizing the attributes of image acquisition context as indexing and retrieval keys for digital image libraries. METHODS: The authors' indexing strategy is based on an interdependent message/terminology architecture that combines the Digital Imaging and Communication in Medicine (DICOM) standard, the SNOMED (Systematized Nomenclature of Human and Veterinary Medicine) vocabulary, and the SNOMED DICOM microglossary. The SNOMED DICOM microglossary provides context-dependent mapping of terminology to DICOM data elements. RESULTS: The capability of embedding standard coded descriptors in DICOM image headers and image-interpretation reports improves the potential for selective retrieval of image-related information. This favorably affects information management in digital libraries.

Abstracting and Indexing↗

PubMedDate not supplied

Tumor necrosis factor receptor 2 plays a minor role for mycobacterial immunity.

Tumor necrosis factor (TNF) signalling via the TNF receptor 1 (TNF-R1) is required for host resistance to mycobacterial infection. The role of TNF-R2 in anti-mycobacterial immunity is not known. Therefore, we compared TNF-R1 and TNF-R2 knockout (KO) mice infected with Mycobacterium bovis BCG (10(7) CFU, i.v.). While the bacterial burden of TNF-R1-deficient mice was significantly increased and the mice succumbed to infection between 4 and 5 weeks, TNF-R2 KO mice were less sensitive, and only 3 of 10 mice died within 12 weeks. Wild-type (WT) mice were resistant to BCG infection. The inability to clear the infection of TNF-R1 KO mice was associated with a reduced delayed-type hypersensitivity (DTH) response to purified protein derivative and severe impairment in forming granulomas with reduced macrophage recruitment and activation, and diminished expression of adhesion molecules. By contrast, TNF-R2 KO mice developed normal DTH response and mature mycobactericidal granulomas as the WT mice. Therefore, anti-mycobacterial immunity is largely dependent on TNF signalling via the TNF-R1, while activation of TNF-R2 plays a minor role.

Animals↗