Multicomponent superconducting order parameter in UTe2.

An unconventional superconducting state was recently discovered in uranium ditelluride (UTe2), in which spin-triplet superconductivity emerges from the paramagnetic normal state of a heavy-fermion material. The coexistence of magnetic fluctuations and superconductivity, together with the crystal structure of this material, suggests that a distinctive set of symmetries, magnetic properties, and topology underlie the superconducting state. Here, we report observations of a nonzero polar Kerr effect and of two transitions in the specific heat upon entering the superconducting state, which together suggest that the superconductivity in UTe2 is characterized by a two-component order parameter that breaks time-reversal symmetry. These data place constraints on the symmetries of the order parameter and inform the discussion on the presence of topological superconductivity in UTe2.

Newborn screening for mucopolysaccharidoses: opinions of patients and their families.

We have conducted a study to assess the opinions of parents of individuals with mucopolysaccharidoses (MPS) and adults with MPS regarding newborn screening (NBS) for this condition, as testing is now technically possible. A questionnaire including a number of hypothetical clinical scenarios about NBS for MPS was distributed to members of MPS support groups from United States and Australia. Questionnaires were returned by 249 members of the US (40% response) and Australian (38% response) support groups. Eleven respondents were adults with MPS and the rest were parents of individuals with MPS. Eighty-six percent of respondents indicated that they would have wanted NBS for their own children. Ninety-seven percent supported the use of NBS for MPS in situations where early treatment that favorably impacts on disease outcome is available, 87% supported NBS when a severe form of MPS was diagnosed, but no treatment is available that improves the long-term outcome and 84% supported NBS for mild MPS where no disease-modifying treatment is available. The most common reason cited in support of NBS was that NBS could avoid a delay in diagnosis and the accompanying distress that delayed diagnosis created. This study has identified strong support for the introduction of NBS for MPS from this group. Psychosocial benefits of screening may outweigh potential harms.

Human vascular smooth muscle cells express receptors for CC chemokines.

Arteriosclerotic lesions are characterized by the accumulation of T lymphocytes and monocytes and the proliferation of intimal smooth muscle cells. Expression of the chemokine monocyte chemoattractant protein-1 (MCP- 1) has been observed in arteriosclerotic plaques and has been proposed to mediate the transendothelial migration of mononuclear cells. More recently, MCP-1 has been proposed to affect the proliferation and migration of vascular smooth muscle cells (VSMCs). We have used reverse transcription-polymerase chain reaction (RT-PCR) to investigate chemokine mRNA expression in human arteriosclerotic lesions obtained from surgical biopsy of diseased vascular tissue and show, in addition to MCP-1, expression of the chemokine macrophage inflammatory protein-1alpha (MIP-1alpha) at higher levels than in "normal" aortic tissue. We have also used RT-PCR to characterize the expression of known chemokine receptors by primary human VSMCs. Messenger RNA for the MIP-1alpha/RANTES receptor, CCR-1, and the MCP-1/MCP-3 receptor, CCR-2, was expressed by unstimulated VSMCs grown under serum-free culture conditions for 24 hours. The receptors CCR-3, CCR-4, CCR-5, CXCR-1, and CXCR-2 were not expressed by VSMCs. The presence of functionally coupled receptors for MIP-1alpha on VSMCs was demonstrated by specific binding of biotinylated MIP-1alpha and increases in intracellular Ca2+ levels after exposure to this chemokine. Taken together, these results suggest that chemokines are likely to be involved in arteriosclerosis and may play a role in modulating the function of VSMCs in vivo.

Malignant melanoma of the toenail apparatus.

BACKGROUND: Subungual melanoma is an unpredictable and aggressive tumor with a propensity to metastasize widely. Because it is an uncommon condition, statistical analysis of its behavior patterns is difficult, factors that determine its prognosis are unclear, and optimal management is ill defined. STUDY DESIGN: A detailed review was undertaken of the clinical and histologic features of subungual melanomas arising from the toenail apparatus in 25 patients treated at the Sydney Melanoma Unit during a 40-year period. Treatment and outcomes were analyzed. RESULTS: Most of the lesions were situated on the great toe in elderly patients of Anglo-Celtic extraction. Antecedent trauma to the toe was frequently reported and delayed diagnosis was usual. There was great variation in Breslow thickness and Clark's level, but these indices were found to have less prognostic significance than for other forms of cutaneous melanoma. CONCLUSIONS: The treatment of subungual melanoma of the toenail apparatus is primarily surgical, by amputation at or proximal to the metatarsophalangeal joint. Even if there is no clinical evidence of metastatic disease in regional lymph nodes, radical node dissection is desirable. The condition is most appropriately managed at a specialist center.

Procedures for the efficient purification of pea seed-borne mosaic virus and its genomic RNA.

An efficient protocol for the purification of pea seed-borne mosaic potyvirus (PSbMV) particles was developed. This led to the purification of 10 PSbMV isolates by a single procedure. Virus aggregation during purification did not occur and consequently, high virus yield was consistently obtained. The virus thus purified was suitable for preparing viral genomic RNA, although conventional methods for RNA extraction resulted in RNA degradation. An alternative method was adopted which yielded reproducibly full length and infectious RNA. This was applied to three isolates of PSbMV and the RNA used to direct complementary DNA synthesis which in turn yielded nearly full length cDNA products.