Labeling of platelets with oxine complexes of Tc-99m and In-111. Part 1. In vitro studies and survival in the rabbit.

We have used both Tc-99m oxine and In-111 oxine to study the effects in the rabbit of various parameters on platelet labeling and the in vivo survival of platelets harvested by four different methods. For In-111 oxine, platelet labeling in saline produces much higher efficiencies (90%) than labeling in the presence of plasma (20%), with no significant shortening of in vivo survival (1% survival at 5.9 days). For Tc-99m oxine, labeling efficiencies are considerably lower (30%) and survival is shorter (1% survival at 3.8 days). For both radioagents, a 30-min labeling incubation at room temperature is suggested.

Platelets labeled with oxine complexes of Tc-99m and In-111. Part 2. Localization of experimentally induced vascular lesions.

Using rabbit platelets harvested and labeled with either Tc-99m or In-111 oxine as described in Part 1, we have successfully imaged experimentally induced fresh venous thrombi and newly injured arterial intima. Visualization of lesions up to 6 hr old is striking. Thrombi and arterial damage 24 hr old, however, were usually not imaged successfully; nor were preformed platelet-poor arterial emboli. The varying rates of platelet deposition in vascular lesions of different ages and types account for these observations. Should human cells prove as effective, widespread clinical application is anticipated.

An evaluation of 99mTc-labeled hepatobiliary agents.

Scintigraphic imaging of the hepatobiliary system has been significantly improved with the development of 99mTc-labeled compounds. Two of the most promising agents, pyridoxylideneglutamate and HIDA, each formed the basis for the development of a group of structural analogs. Condensation of pyridoxal with leucine and arginine (in place of glutamate) produced pyridoxylideneleucine and pyridoxylidenearginine. Since increasing the molecular weight and the lipid solubility of compounds tends to enhance their biliary excretion, several new IDA derivatives were synthesized by altering the lipophilic substituents on the ring of HIDA. The substitutions included ethyl and ethoxy groups as well as iodine. All compounds were compared with 131I-rose bengal using a baboon model that allowed blood, bile, and urine collection.

Singlet oxygen formation in monomeric and aggregated porphyrin c.

The absorption and fluorescence spectra of monomeric and aggregated species present in aqueous solutions of porphyrin c have been resolved by steady-state and time-resolved spectroscopy. The dependence of the singlet oxygen formation yield (phi delta) on excitation wavelength has also been determined. In the Q-band spectral region, the aggregate absorption and emission spectra are shifted to longer wavelengths with respect to the monomer spectrum with phi delta (monomer) = 0.59 and phi delta (aggregate) = 0.33. The relevance of these findings to the optimization of irradiation conditions in tumour phototherapy using porphyrin c are discussed.

Magnetic resonance imaging of cardiac sarcomas.

Two patients with cardiac sarcomas were evaluated with magnetic resonance imaging (MRI). In both cases, MRI provided more information regarding the extent of the tumor than computed tomography, two-dimensional echocardiography, or angiography.

Demonstration of traumatic hepato-pleural-cutaneous defect by 131I-rose bengal.

A 19-year-old man was shot in the right chest about 2 cm below the nipple; bloody fluid was drained through a chest tube. Two days later sero-sanguineous fluid tinged with bile was seen to drain from the wound site. 131I-rose bengal, injected intravenously, collected in the dome of the liver and drained into a collection bag placed over the wound site, thus identifying a hepato-pleural-cutaneous fistula, which was confirmed at surgery.

External exposure estimates for individuals near the Nevada Test Site.

Individuals living near the Nevada Test Site were exposed to both beta and gamma radiations from fission products and activation products resulting from the atmospheric testing of nuclear devices. These exposures, and the resultant doses, were functions of the amount of material deposited, the time of arrival of the debris, and the amount of shielding afforded by structures. Results are presented for each of nine generic life-styles. These are representative of the living patterns of people residing in the area. For each event at each location for which data exist, a representative of each life-style was closely followed for 30 d. The results of these detailed calculations were then extrapolated to the present, employing a stochastic model. Results displayed are the geometric means and standard deviations derived from 25 independent determinations of the various quantities shown. For each determination, required parameters were randomly selected from appropriate distributions. Calculations yielded estimates for: 1) whole-body and skin dose due to gamma rays from material on the ground; 2) skin dose due to beta particles from material deposited directly on the skin; and 3) skin dose due to beta particles from material deposited on the ground. Organ dose estimates were established from the whole-body dose using appropriate conversion factors. For the homemaker life-style, the uterus dose was also calculated as a function of time for 9 mo. This assisted in estimating fetal dose as a function of gestation.

Effects of ethnicity and child's age on maternal judgements of children's transgressions against persons and property.

Mothers (N = 256) of four different cultural groups judged the culpability of children whose actions were described in Piaget-type stories depicting commission of harm under various conditions. Child's age, harm to persons vs material objects, intentions, and amount of harm were systematically varied. All main effects (culture, intent of transgressor, age, and magnitude of harm) were significant, but several effects were qualified interactions. A cognitive social learning explanation is proposed to account for group differences in judgement, with special attention to cultural differences in values attached to harm to persons vs damage to property.

Origin of West Indian populations of the geographically widespread boa Corallus enydris inferred from mitochondrial DNA sequences.

Corallus enydris (Serpentes: Boidae: Boinae) is an arboreal snake with an extremely wide mainland distribution from southern Costa Rica to southeastern Brazil and is one of two boine species that has invaded the Lesser Antilles (Grenada Bank and St. Vincent). Mitochondrial DNA sequences of samples from seven geographically disparate localities provided evidence of phylogenetic relationships. The monophyly of C. enydris is corroborated and a major dichotomy between northern samples (Panama and Trinidad) and southern samples (Guyana, Perú, southeastern Brazil) was found and corresponds to the two currently recognized subspecies. Unexpectedly, the two samples from the West Indies (southern Lesser Antilles) cluster with the southern rather than the geographically closer northern samples (e.g., Trinidad). The results imply a fairly recent Guianan-Amazonian origin of West Indian populations.

Lead extraction from aluminum.

The lead content of various aluminum samples was determined. The amount of lead was found to be in the range from 28-45 ppm. The leaching of lead from aluminum products by 5% acetic acid was negligible at room temperature, but up to 2 mg/liter was leached at 85 degrees C. Although no significant health hazard exists in the usage of aluminum in contact with food items, it is recommended that aluminum containers be conditioned by several extractions with dilute acetic acid at higher temperatures.

Electrophoretic and other studies on haem pigments from Rhodopseudomonas palustris: cytochrome 552 and cytochromoid c.

1. Cytochrome 552 and cytochromoid c were extracted from Rhodopseudomonas palustris cells, purified and obtained in crystalline form. 2. Extinction ratios and amino acid compositions of the two pigments are reported. 3. When subjected to starch-gel electrophoresis in borate buffer, pH8.8, each pigment migrated towards the cathode; oxidized cytochromoid c migrated more rapidly than its reduced form. 4. By a determination of electrophoretic mobilities in buffers of I0.1 by using the moving-boundary method, the isoelectric point of cytochrome 552 was found to be at pH10.6 and that of cytochromoid c at pH9.7. 5. As obtained, cytochrome 552 was non-autoxidizable; cytochromoid c was autoxidizable but became considerably less so on alkaline treatment. 6. Discussion of the results includes a consideration of the isoelectric points of the pigments in terms of their amino acid composition.

Modulation of uptake of heme by rat small intestinal mucosa in iron deficiency.

Although body iron status modulates whole body retention of heme derived iron, it is not known with certainty whether modulation occurs by regulation of mucosal uptake of heme. In vivo uptake from perfused intestine of heme labeled with 14C in the porphyrin ring was studied in groups of rats of differing iron status ranging from fully replete to markedly iron deficient. Heme extraction from infusate and mucosal heme uptake were significantly different between test groups (P < 0.005 and 0.001, respectively). Marked iron deficiency induced a 4.8-fold rise in heme extraction relative to iron-replete animals; rats with latent iron deficiency showed a smaller but still significant rise. Heme extraction correlated negatively with indicators of iron status: hemoglobin (r = -0.76, P < 0.001) and serum iron (r = -0.56, P < 0.05). The specific binding of [14C]heme to purified brush borders from iron-replete and iron-deficient rats was 1.4-fold higher in deficient rats when expressed per milligram of protein (P = 0.046) and 3.3-fold higher when expressed relative to alkaline phosphatase activity (P = 0.014). Thus mucosal uptake of heme in iron deficiency is increased because of an increase in its binding to the brush border.

Use of Rambach Propylene Glycol Containing Agar for identification of Salmonella spp.

When grown on Rambach Propylene Glycol Containing Agar (Rambach agar), 216 of 230 (93.9%) Salmonella organisms isolated from patients and 54 of 62 (87.1%) Salmonella stock cultures produced a crimson-colored growth. Of the 14 clinical Salmonella isolates which displayed colors other than crimson, 8 were Salmonella typhi, 2 were Salmonella paratyphi A, and 4 belonged to other commonly isolated serotypes. All eight Salmonella stock cultures which failed to produce a crimson color belonged to rarely isolated serotypes. In contrast, of 83 non-Salmonella stock cultures distributed among 29 bacterial species, none produced a crimson color. These results suggest that while Rambach agar cannot preidentify S. typhi and S. paratyphi A, the medium can be used for the presumptive identification and can assist in the definitive identification of the overwhelming majority of Salmonella isolates.

Splenic involvement in endemic (murine) typhus: CT findings.

Murine typhus is a rickettsial infection that remains endemic in parts of Texas and California. Clinical manifestations of the infection are due to vasculitis. In a patient who acquired the infection in the United States, computed tomography demonstrated intrasplenic pseudoaneurysms, infarcts, and hemorrhage.