Al(22)Cl(20).12L (L = THF, THP): the first polyhedral aluminum chlorides.

Aluminum subhalides of the type Al(22)X(20).12L (X = Cl, Br; L = THF, THP) are the only known representatives of polyhedral aluminum subhalides and exhibit interesting multicenter bonding properties. Herein, we report on the synthesis and structural investigation of the first chlorides of this type. Additional investigations applying solid-state (27)Al NMR (MAS), XPS (of Al(4)Cp(4) and Al(22)X(20).12L), and quantum chemical calculations shed more light upon the structure of the molecules and possible Al modifications.

Structure assignment in the solid state by the coupling of quantum chemical calculations with NMR experiments: a columnar hexabenzocoronene derivative.

We present a quantum chemical ab initio study which demonstrates a new combined experimental and theoretical approach, whereby a comparison of calculated and experimental (1)H NMR chemical shifts allows the elucidation of structural arrangements in solid-state molecular ensembles, taking advantage of the marked sensitivity of the (1)H chemical shift to intermolecular interactions. Recently, Brown et al. have shown that, under fast magic-angle spinning (MAS) at 35 kHz, the resolution in a (1)H NMR spectrum of the solid phase of an alkyl-substituted hexabenzocoronene (HBC) derivative is sufficient to observe the hitherto unexpected resolution of three distinct aromatic resonances ( J. Am. Chem. Soc. 1999, 121, 6712). Exploiting the additional information about proton proximities provided by (1)H double-quantum (DQ) MAS NMR spectroscopy, it was shown that the results are qualitatively consistent with the aromatic cores packing in a manner similar to that in unsubstituted HBC. Using the HBC-C(12) molecule as an example, we show here that the new combined experimental and theoretical approach allows the observed (1)H chemical shifts to be related in a quantitative manner to the intermolecular structure. In the quantum chemical calculations, a series of model systems of stacked HBC oligomers are used. On account of the marked dependence of the (1)H chemical shift to ring currents arising from nearby aromatic rings, the calculated (1)H chemical shifts are found to be very sensitive to the stacking arrangement of the HBC molecules. Moreover, the ring current effect is found to be particularly long range, with a considerable influence of the second neighbor, at a distance of 700 pm, being observed.

[Influence of Long-Term Stimulation on Pattern-Reversal Visual Evoked Cortical Potentials]. / Einfluss von Langzeitreizung auf das visuell evozierte kortikale Muster-Umkehr-Potential.

In 20 subjects, we recorded the pattern-reversal visual evoked cortical potential (VECP) over a period of 30 min. We could not find any remarkable alterations of the peak times, they were unchanged over the time. During the first 10 min, the amplitudes showed a clear tendency to decrease if one evaluated the averaging value of the whole group. After this time, there were no significant changes. But we learned a quite different behavior of amplitudes evaluating the record of each subject. We found 5 types of different behavioral modulated responses. The problems of long-term investigation are sophisticated and need further investigation to learn which different factors have an impact on VECP. From a clinical point of view, a long-term investigation shows no relevant potential alterations.

A decade of change: the emerging role of the CFO.

The average senior financial executive today in a hospital or corporate healthcare setting is a 42-year-old male who has a master's degree or at least some postgraduate education and who has been in his position for six years, according to a 1991 national survey of healthcare chief financial officers (CFOs). The individual has the title of CFO, earns $82,100, and last year received incentive compensation amounting to 12.3 percent of base salary. He aspires to a higher position, although not necessarily the job of chief executive officer.

Cytokine-stimulation of prostaglandin synthesis from endogenous and exogenous arachidonic acids in polymorphonuclear leukocytes involving activation and new synthesis of cyclooxygenase.

Peripheral blood-derived human polymorphonuclear leukocytes (PMNL) can be induced to synthesize prostaglandin E2 (PGE2) from endogenous and exogenous arachidonic acid (AA) when exposed to agents such as human recombinant (hr) granulocyte-macrophage (GM) colony-stimulating factor (CSF), hr tumor necrosis factor-alpha, hr granulocyte (G)-CSF, lipopolysaccharide and the chemoattractant N-formyl-methionyl-leucyl-phenylalanine. Treatment of PMNL with hr macrophage (M)-CSF and interleukin 3, however, did not result in detectable PGE2 synthesis. Cytokines stimulated PGE2 production during two distinct time intervals, an early peak of PGE2 that was detectable at 20 min and a late one detectable after 4 h. Inhibition of protein synthesis by cycloheximide (CHX) had virtually no effect on the early increase of PGE2 but prevented the late increase. Late addition of CHX to cultures after stimulation with hr GM-CSF at 4 h resulted in decline of PGE2 synthesis from exogenous arachidonic acid. Treatment of PMNL with GM-CSF had direct effects on cyclooxygenase (COx). PMNL depleted from COx by acetyl salicylic acid (ASA) recovered to synthesize PGE2 following exposure to GM-CSF. Recovery from COx inhibition by ASA could be prevented by CHX.

Inducible production of interleukin-6 by human polymorphonuclear neutrophils: role of granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-alpha.

The recent demonstration of the ability of human polymorphonuclear neutrophils (PMN) to secrete various cytokines in response to the granulocyte activator granulocyte-macrophage colony-stimulating factor (GM-CSF) but not to other cytokines, has led to the identification of PMN as biosynthetically active cells. In this study we have investigated the ability of PMN to secrete interleukin-6 (IL-6), a molecule known to be involved in inflammatory reactions. Using RNA blotting analysis and bioassays, we show that PMN could be induced to synthesize transcripts specific for IL-6, indistinguishable in size from IL-6 mRNA produced by activated human macrophages. Consequently, PMN released IL-6-like activity into their culture supernatants that could be neutralized by monospecific anti-IL-6 antibody. Interleukin-6 secretion by PMN, however, required previous stimulation with GM-CSF or tumor necrosis factor-alpha (TNF-alpha), whereas other cytokines, including interleukin-3 (IL-3), granulocyte-CSF (G-CSF), macrophage-CSF (M-CSF), interferon gamma (IFN-gamma), and lymphotoxin (LT), failed to induce IL-6 mRNA accumulation and protein secretion by PMN. Similar to GM-CSF and TNF-alpha, other compounds, including the inhibitor of protein synthesis cyclohexemide (CHX), endotoxin (Escherichia coli-derived lipopolysaccharide), and phorbol myristate acetate (PMA) (but not the chemoattractant N-formyl-methionyl-leucyl-phenylalanine [FMLP]), induced detectable levels of IL-6 transcripts in PMN.

The CFO: a better paid, better prepared executive.

The average senior financial executive in a healthcare organization is a 41-year-old man who has been in his position for 6.1 years. The executive, who usually has the title chief financial officer, earns $62,600 a year and desires to advance to a higher position of responsibility. A new national survey provides a detailed profile of the position.

Today's stronger, tougher, smarter financial manager.

The average CFO is 40 years old and has been in his current position for six years. He (CFOs are still overwhelmingly male) earns $56,615 a year and has increasing responsibility for nontraditional finance functions such as loan administration and real estate management. Furthermore, the CFO is assuming responsibility for other areas such as medical records and contract negotiation. In his professional development, the CFO is becoming increasingly interested in strategic planning, cost accounting to determine pricing, management skills, new business development, and government reimbursement policies. In his personal development, the CFO in finding such personal traits as motivation, drive, the ability to achieve tangible benefits, and strong personal values as ingredients of a successful CFO.

Today's CFO: better educated, better paid, with more responsibility.

The average CFO is 41 years old with a master's degree. He (CFOs are still overwhelmingly male) earns $54,700 a year and has increasing responsibility over areas such as medical records, financial planning, internal audit, and reimbursement. The CFO is becoming increasingly interested in new business activities such as joint ventures and mergers, and is finding government regulations and reimbursement issues a less enjoyable aspect of the job.

A profile of the group practice administrator.

Authors Hamity and Gauss have drawn a profile of today's group practice administrator based on data collected in an independently conducted survey. A report is given on the age, education, and professional background of the 546 respondents. Types of group practice, duties, responsibilities, problematic areas, and salaries and benefits are also discussed. In conclusion, the authors have identified the current and future trends which they believe their data has brought to light.

Whole-body distribution an Malpighian tubule transport of 2',5-dichloro-4'-nitrosalicylanilide (Bayer 73) and 3-trifluoromethyl-4-nitrophenol in larvae of the aquatic midge Chironomus tentans.

1. Residues of the lampricides 14C-Bayer 73 (2',5-dichloro-4'-nitrosalicylanilide) and 14C-TFM (3-trifluoromethyl-4-nitrophenol) were absorbed from aqueous sublethal concn. by aquatic larvae of the midge Chironomus tentans. 2. Toxicant residues were widely distributed during early hours of exposure, but later and during a 24-h post-exposure period, they became concentrated in the trunk and intestinal tract; the posterior movement of Bayer 73 was more rapid than that of TFM. 3. During 4-h tests, Malpighian tubules of the chironomid actively transported Bayer 73 and TFM in vitro, and on a per tubule basis, more TFM was transported than Bayer 73. 4. Potassium cyanide inhibited tubule transport; serotonin had no effect.