Recommended electron-impact excitation and ionization cross sections for Be I

Analytic fits to the recommended electron-impact excitation and ionization cross sections for Be I are presented. The lowest 19 terms of configurations 2snl (n ≤ 4) and 2p ² terms below the first ionization limit are considered. The fits are based on the accurate calculations with the convergent close coupling (CCC) method as well as the B-spline R-matrix (BSR) approach. The fitted cross sections provide rate coefficients that are believed to approximate the original data within 10% with very few exceptions. The oscillator strengths for the dipole-allowed transitions between all the considered states are calculated with the relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) approach and compared with the CCC and BSR results. This comparison shows a very good agreement except for a handful of cases with likely strong cancellations.

Ocular injuries in squash competitors

Squash players are liable to suffer serious eye injuries if they do not take appropriate protective measures. The author presents a short case study which illustrates the type of injury that can be sustained, and argues that nurses and interested associations must become involved in health education activities to reduce the high incidence of injuries during squash matches.

Murine monoclonal antibodies against carcinoembryonic antigen: immunological, pharmacokinetic, and targeting properties in humans

We have examined three 131I-labeled murine monoclonal antibodies (MAbs) against carcinoembryonic antigen (CEA), NP-2, NP-3, and NP-4, after i.v. injection in patients with diverse cancers. Although the MAbs had a similar tumor-targeting ability, several important features were discovered that have led us to the selection of one of these MAbs for further clinical evaluation. We found that it is important to evaluate MAbs with a high immunoreactivity. For example, the MAb NP-2 was used initially in patients with an immunoreactivity between 35 and 50%. Although the tumor-imaging properties of this MAb compared favorably with the affinity-purified, goat anti-CEA antibody that we used previously, further purification of NP-2 to an immunoreactivity greater than 70% uncovered a previously unknown cross-reactivity with human granulocytes. It was also discovered that the MAbs differed in their ability to complex with CEA in the blood. Plasma samples were analyzed by gel filtration at 1 or 24 h after injection. The formation of complexes with circulating CEA was dependent on the CEA:MAb ratio in the blood. NP-3 complexed to a greater degree with CEA than NP-4, but NP-2 did not complex with CEA even at CEA:NP-2 ratios of 55 to 1. NP-3 commonly showed enhanced uptake in the colon by external scintigraphy, and examination of the radioactivity in the stool showed that most of the radioactivity was associated with whole IgG and large-sized fragments of NP-3. We also compared the rate of elimination of radioactivity from the blood for all of the MAbs and compared the clearance of NP-3 to NP-4 at three different ranges of MAb protein doses (less than 1.0 mg, 1 to 5 mg, and 5 to 20 mg). The blood clearance rate for NP-3 was fastest among the other MAbs at protein doses exceeding 1.0 mg. Patients given less than 1.0 mg of NP-4 had a significantly (P less than 0.005) shorter elimination half-life than patients given more than 1.0 mg of NP-4. By virtue of NP-4's good targeting properties in patients and its limited complexation with circulating CEA, it was selected as the MAb of choice for CEA tumor imaging.

Comparison of tumor targeting in nude mice by murine monoclonal antibodies directed against different human colorectal cancer antigens

Tumor targeting of five radioiodinated murine monoclonal antibodies (MAbs) directed against human colorectal cancer were studied in nude mice bearing the GW-39 human colonic tumor xenograft. All of the MAbs are of the IgG1 isotype. Two of the MAbs (NP-4 and MN-14) are directed against a Class III carcinoembryonic antigen-specific epitope, but they differ 10-fold in their affinity. The other three MAbs recognize mucins found in colonic cancer. Mu-9 recognizes a peptide determinant similar to that described previously for a polyclonal goat anti-colon-specific antigen p. G9 identifies an organ-specific, tumor-associated carbohydrate epitope. The tumor targeting of these MAbs was compared to that of B72.3, another anti-mucin MAb. The tumor uptake of all the MAbs were similar on days 1, 3, and 7, with an average maximum accretion of between 30 and 40%/g tumor occurring by day 3. This tumor uptake was maintained for 14 days with the anti-mucin MAbs, whereas the percentage of injected dose/g in the tumor for 2 anti-carcinoembryonic antigen MAbs decreased 2-fold by day 14. Although no statistical difference could be found between the percentage of injected dose/g in the tumor for NP-4 and MN-14 (carcinoembryonic antigen MAbs), in a paired-labeled study using 131I-MN-14 and 125I-NP-4, MN-14 uptake in the tumor was consistently 1.3 times higher than that of NP-4 on all days tested. F(ab')2 fragments showed lower tumor uptake (maximum uptake for NP-4 and Mu-9 was 11% on day 1), but the faster clearance resulted in a 4- to 40-fold increase in tumor/blood ratios on day 3 in comparison to the whole IgGs. Fab' fragments had the lowest tumor uptake of the 3 forms of immunoglobulin, with a maximum of only 5%/g 6 h after injection. However, tumor/blood ratios on day 1 for the Fab' fragments were improved 3-fold over that of F(ab')2. All of these MAbs, except Mu-9, identify epitopes that can be detected in plasma, but none of the MAbs complexed appreciably when mixed in vitro with plasma containing antigen at antigen/MAb ratios anticipated to be encountered most frequently in imaging or therapy applications in humans. However, complexation of the MAbs will occur if antigen in the plasma is markedly elevated. These studies suggest that if used clinically, tumor targeting of colorectal cancer with any of these MAb IgG may be similar if these antigens are present at relatively similar concentrations in tumor.(ABSTRACT TRUNCATED AT 400 WORDS)

The Effects of Stimulation of the Hypothalamic Pupillo-Dilator Centre after Successful Anastomoses Between the Cervical Sympathetic and Certain Motor Nerves

Images

Clinical and Experimental Observations introducing a Discussion on the Regeneration of Peripheral Nerves; an Address

Images