Malpractice Woes: Here Is What You Should Do if You Get Sued.

This article relates the first-hand experience of a surgeon who faced 2 medical malpractice actions separated by 30 years and how each of those experiences affected him. The first episode occurred early in his career and caused anxiety, fear, and anger. The importance of getting support during a medical malpractice event, and the opportunities to do so, are discussed.

Growth kinetics of polymer crystals in bulk.

Temperature-dependent measurements of spherulite growth rates carried out for i-polystyrene, poly(epsilon -caprolactone) and linear polyethylene show that the controlling activation barrier diverges at a temperature which is 14K, 22K and 12K, respectively, below the equilibrium melting points. We discuss the existence of such a "zero growth temperature" T(zg) in the framework of a recently introduced thermodynamic multiphase scheme and identify T(zg) with the temperature of a (hidden) transition between the melt and a mesomorphic phase which mediates the crystal growth. The rate-determining step in our model of crystal growth is the attachment of chain sequences from the melt onto the lateral face of a mesomorphic layer at the growth front.

A thermodynamic multiphase scheme treating polymer crystallization and melting.

A comparison of transition and melting temperatures of n-alkanes with experimentally determined ticknesses and melting points of polyethylene lamellae shows that the variation of the thickness with the crystallization temperature virtually agrees with the chain length dependence of the crystalline-mesomorphic phase transition in n-alkanes. Mesomorphic polyethylene layers are stable objects up to the thickness set by this phase transition. The findings lend further support to the view that polymer crystallization generally uses a route which includes a passage via a mesomorphic phase.

Crystallization of poly(ethylene-co-octene): II. Melt memory effects on first order kinetics.

Dilatometric and X-ray scattering experiments of the crystallization kinetics of a sample of poly(ethylene-co-octene) show pronounced melt memory effects, i.e., the shapes of isotherms and characteristic times vary systematically with the temperature of the melt prior to cooling to the crystallization temperature.

Crystallization of a poly(ethylene-co-octene): I. A precursor structure and two competing mechanisms.

Observations of a sample of poly(ethylene-co-octene)in a polarizing optical microscope reveal peculiarities in its crystallization behavior. When cooled from the melt to a fixed crystallization temperature, at first a structure of diffuse appearance with variations on the length scale of micrometers forms rapidly. The transformation into the final semi-crystalline state then proceeds in two ways, by a continuous change of the inner structure of microm-sized objects and by the growth of spherulites.

Characteristic variations in the effect of diluents on polymer crystallization and melting observed for a sample of poly(ethylene-co-octene).

Melting points in mixtures of a crystallizable polymer with a low-molar-mass diluent depend on both, the diluent fraction and the crystal thickness. A differentiation of the two factors can be achieved by temperature-dependent SAXS experiments. A corresponding study, complemented by DSC, dilatometry, microscopy and AFM-imaging, was carried out for mixtures of a poly(ethylene-co-octene) with n-C16H34, c-C16H32 and methyl-anthracene, respectively.

Role of the entangled amorphous network in tensile deformation of semicrystalline polymers.

Being composed of crystalline lamellae and entangled amorphous polymeric chains in between, semicrystalline polymers always show a complicated deformation behavior under tensile deformation. In recent years, the process of tensile deformation was found to exhibit several regimes: intralamellar slipping of crystalline blocks occurs at small deformation whereas a stress-induced crystalline block disaggregation-recrystallization process occurs at a strain larger than the yield strain. The strain at this transition point is related to the interplay between the amorphous entanglement density and the stability of crystal blocks.

Development of a pharmacophore for inhibition of human liver cytochrome P-450 2D6: molecular modeling and inhibition studies.

To gain insight into the specificity of cytochrome P-450 2D6 toward inhibitors, a preliminary pharmacophore model was built up using strong competitive inhibitors. Ajmalicine (1), the strongest inhibitor known (Ki = 3 nM) was selected as template because of its rigid structure. The preliminary pharmacophore model was validated by performing inhibition studies with derivatives of ajmalicine (1) and quinidine (9).

Quinolone antibacterial agents: relationship between structure and in vitro inhibition of the human cytochrome P450 isoform CYP1A2.

The inhibitory effect of 44 quinolone antibacterials and derivatives (common structure, 4-oxoquinoline-3-carboxylic acid) on cytochrome P450 isoform CYP1A2 activity was tested using human liver microsomes and caffeine 3-demethylation as a specific test system for this enzyme. By direct comparison of molecules differing structurally in only one position, the following structure-activity relationships were found. 3'-Oxo derivatives had a reduced or similar activity and M1 metabolites (cleavage of piperazinyl substituent) had a greater inhibitory activity, compared with the parent molecule.

The tungsten-containing aldehyde oxidoreductase from Clostridium thermoaceticum and its complex with a viologen-accepting NADPH oxidoreductase.

Purification of aldehyde oxidoreductase from C. thermoaceticum, the first detected enzyme able to reduce reversibly non-activated carboxylic acids to the corresponding aldehydes (White, H., Strobl, G.

13C and 15N NMR studies on the interaction between 6,7-dimethyl-8-ribityllumazine and lumazine protein.

The interaction between the prosthetic group 6,7-dimethyl-8-(1'-D-ribityl)lumazine and the lumazine apoproteins from two marine bioluminescent bacteria, one from a relatively thermophilic species, Photobacterium leiognathi, and the other from a psychrophilic species, Photobacterium phosphoreum, was studied by 13C and 15N NMR using various selectively enriched derivatives. It is shown that the electron distribution in the protein-bound 6,7-dimethyl-8-ribityllumazine differs from that of free 6,7-dimethyl-8-ribityllumazine in buffer. The 13C and 15N chemical shifts indicate that the protein-bound 6,7-dimethyl-8-ribityllumazine is embedded in a polar environment and that the ring system is strongly polarized.

Carboxylic acid reductase: a new tungsten enzyme catalyses the reduction of non-activated carboxylic acids to aldehydes.

An enzyme which we call carboxylic acid reductase (aldehyde dehydrogenase) seems to be the first which is able to reduce non-activated carboxylic acids to aldehydes at the expense of reduced viologens. There is no further reduction of the aldehydes to the corresponding alcohols. In the presence of oxidized viologens aldehydes can be dehydrogenated to carboxylic acids roughly 20 times faster than the latter are reduced.

[The diagnostic value of cranial computerized tomography in exogenous psychoses and mental disorders associated with organic disease (author's transl)].

205 patients hospitalized in a psychiatric department were subjected to cranial computerized tomography. The diagnosis on discharge according to the ICD key in each case was "psychoses or mental disorders associated with physical conditions". Pathological findings were obtained in 67.

[Quantitative evaluation of lateral ventricle width by means of CT--values obtained from a normal population (author's transl)].

The possibilities of differentiation between a "normal" and an "enlarged" ventricular system by means of Computerized Tomography are limited. The main problems are the definition of the Normal Population and the fact that a certain methodical error in measurement is not to be avoided. On the other hand, that differentiation is essential for the diagnosis of Ventricular Enlargement, Hydrocephalus internus and Brain Atrophy.

[Indications for neuroradiological investigations using contrast media in patients with psychiatric disorders (author's transl)].

The results are presented of neuroradiological investigations using contrast media in 100 patients hospitalized in a psychiatric department. The existence of neurological disturbances or the psychoorganic syndrome, as well as the results of screening methods such as EEG and brain scan are important factors in the decision for or against the performance of cerebral angiography or pneumoencephalography. The significance of the "brain atrophy syndrome" accompanying psychotic diseases is discussed.

[Sport and cardiac risk factors in middle age (author's transl)].

1477 employees (868 males and 609 females) were examined for cardiac risk factors. The risk factor frequency was tested in relation to the amount of physical activity. Men and women active in sports are less subject to over-weight, diabetes, high blood pressure, and pathological ECG changes than are physically inactive; males who participate in sports also smoke less.

[Coronary risk factors and social class. Screening in employees of a large industrial firm (author's transl)].

In Munich, 1477 employees (868 males and 609 females) of a large industrial firm were examined with regard to coronary heart disease risk factors. The known risk factors--overweight, disorders of the lipometabolism, diabetes, cigarette smoking, hypertension, pathologic ECG, physical inactivity--as well as certain somatic complaints and mental stress were checked for their distribution within the various social levels. With the exception of cigarette smoking among women and professional worries among men, in both sexes the members of the upper social group are less burdened with danger factors than the average.

Reversal by physostigmine of clozapine-induced delirium.

Clozapine, a new antipsychotic drug without extrapyramidal side effects and with strong sedating potency, can produce acute symptoms of central anticholinergic toxicity. The authors report that physostigmine, a reversible anticholinesterase agent, which can pass the blood-brain barrier, was effective in reversing the clozapine-induced brain syndrome in two patients. Physostigmine also reduced one patient's tachycardia.

Slow-drip dibenzepine infusion in depression. Proof of rapid efficacy by quantitative EEG and affect-polarity profile studies.

The efficacy of a new intensive antidepressive treatment procedure--48 h slow drip infusion with 1,440 mg dibenzepine2 and subsequent oral treatment--was investigated in endomorphous (endogenous) depressed patients. In addition to evaluations of alterations in psychopathology by clinicians, time of onset and the extent of the therapeutic effect was determined by the patients themselves using the affect-polarity profile, and by EEG power-spectral density analysis. Clinical improvement started as early as in the 3rd hour of the dibenzepine infusion and was predominantly due to an anxiolytic/sedative drug effect.