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The structure of the title compound, 5,6-[(1R,10S)-2,9-dioxatri-cyclo-[8.6.0(3,8).0(11,16)]hexa-decane-1,10-di-yl]-(C60-Ih)[5,6]fullerene methane-dithione 0.1-solvate, C74H10O2·0.1CS2, has tetra-gonal (P42/n) symmetry at 100 K. It has a unique eight-membered ring, with two incorporated O atoms in place of the original central ring of the anthracene. The distortion of the mol-ecular geometry around the cyclo-adduct bonds corresponds to that seen in related fullerene derivatives. Close packing of the adduct forms cavities partially filled with disordered carbon di-sulfide solvent mol-ecule. The 41% occupancy of the cavities yields an overall 1:0.103 adduct-solvent ratio. Reaction steps are described as light-assisted singlet-oxygen generation, peroxide, epoxide and dioxocin derivative formation and the final step of thermally activated cyclo-addition.

Human herpesvirus 7 known since 1990 is closely related to herpesvirus 6B. It replicates in human cells only after binding CD4 receptor. It establishes lifelong latency in infected cells, and its frequent reactivations result in asymptomatic virus shedding through saliva. Most children acquire infection by age 3 and 4, but in any later age group seronegative individuals are at risk of infection. Rarely, exanthema subitum or convulsions with fever in children, pityriasis rosea in young adults, lethal complications in immunocompromised persons with concomitant herpesvirus 6B and cytomegalovirus reactivation occur. The most important pathogenic changes are due to the altered cytokine and growth factor secretion from infected lymphocytes with subsequent chain reaction on immune and other cells. Antiviral antibodies are detected by commercial kits (immunofluorescence, ELISA, immunoblot), nucleic acid by nested polymerase chain reaction. The majority of conditions due to infection do not require antiviral medication, but the severe complications are treated with ganciclovir and its derivates or foscarnet and cidofovir.

Cocrystals of cubane and fullerenes, C60-cubane and C70-cubane, show distinct rotational ordering transitions. We studied the corresponding structural changes with temperature-dependent X-ray diffraction and the thermodynamics of the phase transitions with adiabatic microcalorimetry and differential scanning calorimetry. C60-cubane has one phase transition around 130 K from a high-temperature fcc phase with freely rotating C60 to a low-temperature orthorombic phase in which the fullerene rotation is frozen. The corresponding enthalpy change is approximately 1170 J/mol, and the entropy change is 9.6 J/(mol K). C70-cubane has two phase transitions. Around 380 K, the high-temperature fcc phase with freely rotating C70 transforms into a bct phase in which the C70 rotates uniaxially around an axis that precesses around the c direction with a full opening angle of 40 degree. Around 170 K, the uniaxial rotation also freezes out, with an accompanying structural transition to monoclinic and enthalpy and entropy changes of 620 J/mol and 8.7 J/(mol K), respectively. The low-temperature specific heat was analyzed in terms of the Debye-Einstein model to estimate the librational energies of the fullerenes and Debye temperatures. We found very similar values for the two cocrystals, approximately Elib = 2.2 meV and TDebye = 23 K. For reference, we also measured the specific heats of pure C60 and C70 and found Elib = 2.96 meV and TDebye = 32 K for C60 and Elib = 1.9 meV and TDebye = 20 K for C70.

C(60).C(8)H(8) and C(70).C(8)H(8) are prototypes of rotor-stator cocrystals. We present infrared and Raman spectra of these materials and show how the rotor-stator nature is reflected in their vibrational properties. We measured the vibrational spectra of the polymer phases poly(C(60)C(8)H(8)) and poly(C(70)C(8)H(8)) resulting from a solid-state reaction occurring on heating. On the basis of the spectra, we propose a connection pattern for the fullerene in poly(C(60)C(8)H(8)), where the symmetry of the C(60) molecule is D(2h). On illuminating the C(60).C(8)H(8) cocrystal with green or blue light, a photochemical reaction was observed leading to a product similar to that of the thermal polymerization.

Cubane (C8H8) and fullerene (C60) are famous cage molecules with shapes of platonic or archimedean solids. Their remarkable chemical and solid-state properties have induced great scientific interest. Both materials form polymorphic crystals of molecules with variable orientational ordering. The idea of intercalating fullerene with cubane was raised several years ago but no attempts at preparation have been reported. Here we show that C60 and similarly C70 form high-symmetry molecular crystals with cubane owing to topological molecular recognition between the convex surface of fullerenes and the concave cubane. Static cubane occupies the octahedral voids of the face-centred-cubic structures and acts as a bearing between the rotating fullerene molecules. The smooth contact of the rotor and stator molecules decreases significantly the temperature of orientational ordering. These materials have great topochemical importance: at elevated temperatures they transform to high-stability covalent derivatives although preserving their crystalline appearance. The size-dependent molecular recognition promises selective formation of related structures with higher fullerenes and/or substituted cubanes.

In periodontal diseases where the loss of periodontal tissue is very extensive, displacement of the teeth may be observed. In the interest of complete healing, periodontal treatment must be followed by orthodontic treatment in such patients. If the basic rules relating to adult patients with a reduced, but healthy periodontium are adhered to, the orthodontics can be carried out with certainty in adults who have been rehabilitated from a periodontal aspect. An improved long-term result may be observed in the patients who participate in such complex rehabilitation. Teeth that have been restored to their correct position are not only aesthetically more attractive, but also function more appropriately, are easier to keep clean, and can be treated more simply.

We produced C60 photopolymer in gram quantity by a new monomer recycling method and extracted its soluble components. The most abundant components, the (2 + 2) cycloadduct dimer, C120, and several oligomers were isolated by high-performance liquid chromatography (HPLC). Three different C180 isomers were identified on the basis of their formation and decomposition reactions. The crystal structure of the insoluble photopolymer is face-centered cubic (fcc) with a contracted lattice parameter relative to the pristine C60. The lattice parameter and the amounts of soluble oligomers depend on the preparation temperature. We explain this variation with a topochemical model of photopolymerization: The geometrical conditions allow the formation of only linear or planar oligomers in the triangular or square sublattices. Competing reactions in the intersecting planes prevent the formation of large oligomers. The lattice contraction is proportional to the number of cycloadduct bonds.

A polar type liquid having a secondary alcohol substituent on a branched alkane skeleton, SOH, was used as stationary phase. The molecules of this stationary phase are nearly isomorphous and isochor with those of the branched alkane, C78, elected as standard, i.e., the molecules of both solvents have nearly the same form and the same size. Partition properties of 158 chosen molecular probes were measured by gas chromatography on SOH and on an SOH-C78 mixture having a volume fraction of thetaOH = 0.5. Based on the resulting data an interaction free enthalpy could be calculated, i.e., the additional effect of the secondary alcohol to partition. Comparison with data determined earlier on another member of this solvent family, POH, having a primary alcohol as interacting group gives information about the effect of steric hindrance on polar type solute-solvent interaction free energies.

The authors report a case of fetal supraventricular tachycardia with the heart rate of 400/min diagnosed in the 34th week of pregnancy. Congestive heart failure forming non immun hydrops fetalis was occurred by this rhythm disturbance. With digitalis and beta receptor blocker propranolol therapy administered to the mother the rhythm disturbance has stopped, ascites and hydrothorax secondary to fetal congestive heart failure have been abolished. Congenital heart disease and cardiomyopathy were excluded by fetal echocardiography. In the 40th week a healthy newborn was delivered by cesarean section and after delivery congenital heart disease, rhythm disorder, infection or metabolic disturbance couldn't be verified. The authors reviewing the literature demonstrate the suggested investigating procedures and the possibilities of therapy in the case of fetal supraventricular tachycardia.

Thin-layer chromatographic (TLC) separation techniques were used to analyze the heterogeneity of various preparations which included smooth and rough endotoxins (ET), Lipid A precipitates and synthetic Lipid A samples and a novel cytotoxic bacterial lipid. Furthermore, carbohydrate-rich split products (PS) of ET were also separated on commercial silica-coated plates. Satisfactory results were obtained by two-dimensional TLC or by the combination of chromatography followed by high-voltage electrophoresis in the separation of PS of ET cleaved by mild acetic hydrolysis. Several spray reagents were found which were eminently suitable to detect carbohydrate containing compounds. Less specific but generally useful spray reagents were also developed which gave strong color reactions with lipids, proteinaceous and carbohydrate containing split products of the ET preparations. Improved chromatographic resolution has also revealed substantial heterogeneity in both rough and smooth ET samples. Three biological activities of the separated components could be determined. These were antigenicity detected by reactivity with monoclonal antibodies on the TLC plates, endotoxicity, determined by the Limulus amoebocyte lysate (LAL) test and direct cytotoxicity of P815 cells in vitro. Considerable amounts of non-endotoxic and non-antigenic contaminants could be detected in all preparations tested. Significant amounts of free Lipid A were also found in smooth ETs. Thus a new level of complexity is recognized by TLC within these preparations.