Sub-Doppler Infrared Spectra and Torsion-Rotation Energy Manifold of Methanol in the CH-Stretch Fundamental Region

The infrared spectrum of jet-cooled methanol in the CH-stretch fundamental region has been investigated by two sub-Doppler laser techniques: optothermally detected molecular-beam electric resonance and direct-absorption slit-jet spectroscopy. With the aid of microwave-infrared double resonance and ground state combination differences, 27 subbands in the frequency range 2967 to 3027 cm-1 have been assigned to the nu2 fundamental. Perturbation systems in the K' = 0 E, -1 E, and -2 E symmetry subbands have been analyzed to yield matrix elements of 0.013, 0.041, and 0.75 cm-1, respectively. The A-E torsional tunneling splitting for J = 0 of the nu2 vibration of -3.26 cm-1 is of opposite sign and a factor of three smaller in magnitude than the ground state value of +9.12 cm-1. Copyright 1997 Academic Press. Copyright 1997Academic Press     

Merkel cell carcinoma of the skin

Primary neuroendocrine carcinoma of the skin or Merkel cell carcinoma is an aggressive primary neoplasm. It is commonly seen in the elderly, on the head, neck and extremities, where it can mimic a benign or less malignant skin tumour. Pathological examination shows a generally dense growth of small dark cells, with immunohistochemical evidence of neuroendocrine differentiation. The microscopic appearance is very similar to metastatic oat cell carcinoma from the lung and this must be excluded by clinical means and appropriate imaging studies. In this study we present 13 new cases of Merkel cell carcinoma (the largest published series in the UK) and summarize 214 cases from the literature in which the survival data are given. In our series, 5 of 13 patients died from spread of the Merkel cell carcinoma. From this and other studies, it appears that early diagnosis and wide local excision may be the only way to prolong survival. No other adjuvant therapy has proved effective.     

SPECT imaging of dopamine transporters in human brain with iodine-123-fluoroalkyl analogs of beta-CIT

Iodine-123-2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane (beta-CIT) is a useful SPECT tracer for imaging the dopamine transporter. Its slow kinetics, however, necessitate imaging on the day after the injection. Two N-omega-fluoroalkyl analogs of beta-CIT, the fluoropropyl and fluoroethyl compounds (beta-CIT-FP and beta-CIT-FE, respectively), characterized by faster kinetics in baboons, were tested in humans as potential tracers for the dopamine transporter. Four healthy volunteers were injected with [123I]-beta-CIT-FP and another four were injected with [123I]beta-CIT-FE. SPECT data were acquired for 1149 +/- 590 min and 240 +/- 30 min, respectively. Both tracers demonstrated high brain uptake (6.37% +/- 0.37% and 7.8% +/- 1.5% of the injected dose, respectively). Activity concentrated with time in the striatal area, reaching a peak within 30 min, with little or no washout for [123I]beta-CIT-FP and a faster washout for [123I]beta-CIT-FE (14.7% +/- 6.9%). Occipital and midbrain activity showed similar patterns, displaying a peak within 15 min and rapid washout, followed by stable levels at approximately 100 min for both tracers. The ratio of peak specific striatal-to-peak specific midbrain activity was 9.1 +/- 1.8 for [123I]beta-CIT-FP and 7.7 +/- 0.7 for [123I]beta-CIT-FE, showing high in vivo selectivity for the dopamine transporter. These preliminary results suggest that both compounds could be used as SPECT (labeled with 123I) or PET (labeled with 18F) radiotracers to image the dopamine transporters in the living human brain.     

The differing prognostic utility of exercise radionuclide ventriculography in coronary artery disease patients with and without prior myocardial infarction

Previous studies have documented the prognostic utility of left ventricular ejection fraction response to exercise primarily in populations without prior myocardial infarction. We undertook a study to assess the prognostic utility of exercise left ventricular ejection fraction and segmental wall motion response during exercise radionuclide ventriculography in coronary artery disease patients with and without prior myocardial infarction. METHODS: We examined the comparative prognostic utility of left ventricular ejection fraction and segmental wall motion response during upright bicycle exercise radionuclide ventriculography in 419 coronary artery disease patients with (n = 217) and without (n = 202) prior myocardial infarction using univariate and multivariate hierarchical regression analyses. RESULTS: During an average followup period of 61 months, 96 patients (23%) suffered cardiac events, including 55/217 (25%) of the patients with prior myocardial infarction and 41/200 (21%) of the patients without prior myocardial infarction (p = ns). Both cumulative Kaplan-Meier survival analyses and stepwise hierarchical Cox survival analyses demonstrated that peak left ventricular ejection fraction < 55% was a significant predictor of cardiac events in patients without prior myocardial infarction (p = 0.04), whereas an exercise wall motion worsening score > or = 2 was a significant predictor in patients with a prior myocardial infarction (p = 0.0001). CONCLUSIONS: The prognostic utility of exercise radionuclide ventriculography variables differ according to the presence or absence of prior myocardial infarction. Global function, assessed by peak left ventricular ejection fraction, adds the greatest prognostic information in patients without prior myocardial infarction, whereas regional function, assessed by exercise wall motion worsening, is the best predictor among patients with prior myocardial infarction.     

Socioeconomic status differences in hormone therapy

Socioeconomic status (SES) is a significant sociodemographic correlate of noncontraceptive hormone therapy, yet multiple dimensions of SES have not been examined systematically in previous studies of hormone therapy. This study examined the lifetime incidence of noncontraceptive hormone therapy, how usage varied by type of reproductive organ surgery, and the bivariate and net associations between a large array of SES indicators and the likelihood of ever using hormones by age 53-54 years in a population sample (n = 3,612) of non-Hispanic white female participants in the Wisconsin Longitudinal Study (1957-1993). Approximately half of the women had ever used noncontraceptive hormones; 38.5% were current users. In multivariate logistic regression analyses, the most robust SES predictor of hormone therapy was a woman's husband's occupational status (higher status associated with higher rates of use), after adjustment for all other measured sociologic and biomedical factors (e.g., other SES measures, other health behaviors, menopausal symptoms, age at menopause, health insurance). The association of hormone therapy with education differed between women who underwent hysterectomy and/or oophorectomy (higher odds for less educated women) and those with intact reproductive organs (lower odds for less educated women). Additionally, a woman's own earnings and household net worth were positive net correlates of noncontraceptive hormone therapy.     

Diagnostic procedures for catheter malfunction in programmable implantable intraperitoneal insulin infusion devices

N-terminal chain extension of unprotected amino acid amides and peptides with dipeptide amides using Cathepsin C (dipeptidyl aminopeptidase I, EC 3.4.14.1)-mediated reverse proteolysis in water was studied. Taking Pro-X-NH2 as the acyl donor, the sensitivity of the kinetically controlled peptide, coupling to pH value, temperature, acetonitrile addition, and nucleophile type were investigated. Basic or hydrophobic amino acids as the alpha-amino-N-nucleophile proved to be much more prone to catalyzed bond formation than their neutral, hydrophilic, or negatively charged analogues. In a preparative run a pentapeptide was obtained with 83% yield by directed and regioselective coupling of ProTrpNH2 with LysLeuPheNH2 catalyzed by Cathepsin C in aqueous buffer.