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The ability of cells to resist the cytolytic actions of tumour necrosis factor (TNF) has been shown to require TNF-induccd gene expression. It has been shown in some human cells that the gene encoding manganese superoxide dismutase (MnSOD), a TNF-induced gene, can provide resistance to TNF killing. Variation in the sensitivity to TNF was observed during subcloning of mouse SV4O- transformed cell lines. This variation fell into three phenotypic classes. Cells were found that were either always resistant to TNF, always sensitive to TNF, and sensitive to TNF if inhibitors of transcription or translation were present. To determine if the regulation of MnSOD was responsible for the TNF sensitivity, Northern blot analysis was carried out. These experiments showed no correlation between expression and/or induction of the MnSOD mRNA and sensitivity or resistance to TNF. These data suggest that other pathways and gene products must therefore play a role for cells to resist TNF-mediated cellular lysis. [ABSTRACT FROM AUTHOR]

Patients from two unrelated families, one from Bristol (two individuals) and the other from Stoke-on-Trent (seven individuals), who exhibited the clinical triad of speckled hyperpigmentation, palmo-plantar punctate keratoses and a blistering tendency particularly on hands and feet in infancy, are recorded. The disorder was inherited as an autosomal trait. The relationship of this clinical triad to other recently reported inherited conditions in which it has been encountered is discussed. A plea for a unified nomenclature is made. [ABSTRACT FROM AUTHOR]

In ten patients suffering from symptomatic dermographism the combined administration of chlorpheniramine + cimetidine produced a greater reduction in the weal and flare response provoked by a standardized scratch than the administration of chlopheniramine alone. There was a statistically significant improvement in the overall assessment of the patinet's skin condition with the combined administration of chlopheniramine + cimetidine. Chlorpheniramine given alone produced no significant benefit whilst cimetidine alone produced a marked exacerbation in Stching in nearly half the patients who initially entered the study and was sufficient to require withdrawal. [ABSTRACT FROM AUTHOR]

A case of porphyria cutanea tarda induced by oral contraceptive pill therapy is reported, and its unusual presenting sign of onycholysis of the finger nails is noted. Reference is made to the rarity of nail changes in porphyria and the regression of the onycholysis in the patient following therapy is outlined. [ABSTRACT FROM PUBLISHER]

We report on Fourier spectroscopy experiments performed with near-surface nitrogen-vacancy centers in a diamond chip. By detecting the free precession of nuclear spins rather than applying a multipulse quantum sensing protocol, we are able to unambiguously identify the NMR species devoid of harmonics. We further show that, by engineering different Hamiltonians during free precession, the hyperfine coupling parameters as well as the nuclear Larmor frequency can be selectively measured with up to five digits of precision. The protocols can be combined to demonstrate two-dimensional Fourier spectroscopy. Presented techniques will be useful for mapping nuclear coordinates in molecules deposited on diamond sensor chips, en route to imaging their atomic structure. [ABSTRACT FROM AUTHOR]

We investigate the application of amplitude-shaped control pulses for enhancing the time and frequency resolution of multipulse quantum sensing sequences. Using the electronic spin of a single nitrogen-vacancy center in diamond and up to 10 000 coherent microwave pulses with a cosine square envelope, we demonstrate 0.6-ps timing resolution for the interpulse delay. This represents a refinement by over 3 orders of magnitude compared to the 2-ns hardware sampling. We apply the method for the detection of external ac magnetic fields and nuclear magnetic resonance signals of 13C spins with high spectral resolution. Our method is simple to implement and especially useful for quantum applications that require fast phase gates, many control pulses, and high fidelity. [ABSTRACT FROM AUTHOR]

We report hyperpolarization of the electronic spins associated with substitutional nitrogen defects in bulk diamond crystals. Hyperpolarization is achieved by optical pumping of nitrogen vacancy centers followed by rapid cross relaxation at the energy level matching condition in a 51 mT bias field. The maximum observed donor spin polarization is 0.9%, corresponding to an enhancement of 25 compared to the thermal Boltzmann polarization. A further accumulation of polarization is impeded by an anomalous optical saturation effect that we attribute to charge state conversion processes. Hyperpolarized nitrogen donors may form a useful resource for increasing the efficiency of diamond-based dynamic nuclear polarization devices. [ABSTRACT FROM AUTHOR]