The 5-D itch scale: a new measure of pruritus.

BACKGROUND: Itching is a subjective and multidimensional experience which is difficult to quantify. Most methodologies to assess itching suffer from being unidimensional, for example only measuring intensity without impact on quality of life, or only measuring scratching activity. None has actually been demonstrated to be able to detect change over time, which is essential to using them as an outcome measure of response to an intervention. The 5-D itch scale was developed as a brief but multidimensional questionnaire designed to be useful as an outcome measure in clinical trials. The five dimensions are degree, duration, direction, disability and distribution. OBJECTIVES: To study the 5-D with respect to validity, reliability and response to change. METHODS: The 5-D was administered to 234 individuals with chronic pruritus due to liver disease (n = 63), kidney disease (n = 36), dermatological disorders (n = 56), HIV/AIDS (n = 28) and burn injuries (n = 51). The 5-D was administered at baseline and after a 6-week follow-up period. A subset of 50 untreated patients was retested after 3 days to assess test-retest reliability. RESULTS: The 5-D score correlated strongly with a visual analogue score: r = 0.727 at baseline (P < 0.0001), r = 0.868 at the 3-day repeat (P < 0.0001), and r = 0.892 at the 6-week follow-up (P < 0.0001). There was no change in mean 5-D score between day 1 and day 3 in untreated individuals (intraclass correlation coefficient = 0.96, P < 0.0001). The 5-D did, however, detect significant changes in pruritus over the 6-week follow-up period (P < 0.0001). Subanalysis of the different patient groups revealed similar response patterns and scores, with the exception of lower total scores for the burn victims due to lower scores on the distribution domain because they itched only at the site of their burn. CONCLUSIONS: The 5-D, therefore, is a reliable, multidimensional measure of itching that has been validated in patients with chronic pruritus to able to detect changes over time. The 5-D should be useful as an outcome measure in clinical trials.

Fatal human melioidosis acquired in a subtropical Australian city.

We describe an acute fatal human case of melioidosis acquired in Ipswich, a city at 27.5 degrees S in southern Queensland, south of the area traditionally considered endemic for melioidosis in Australia. Molecular typing revealed that this patient isolate was genetically distinct from 2 other human and 1 bovine isolates of Burkholderia pseudomallei from the same region and from 4 tropical northern Australian strains. This finding suggests that if B. pseudomallei has been introduced to the region from northern Australia, it was not in recent times, and there has not been a point source of infection. Burkholderia pseudomallei is present in temperate southern Queensland, which hitherto has not been well appreciated. Clinicians should consider the diagnosis of acute melioidosis in patients with severe pneumonia or septicemia acquired in subtropical areas such as southern Queensland, particularly after heavy summer rains with flooding.

Similar T-cell oligoclonality in antimitochondrial antibody-positive and -negative primary biliary cirrhosis.

Approximately 5% of patients with clinical and histological features suggestive of primary biliary cirrhosis do not have anti-mitochondrial antibodies that can be detected by current methodologies. Although the role of these autoantibodies in the pathogenesis of liver disease is uncertain, T lymphocytes within the portal tracts are felt to be important mediators of bile duct destruction. In order to investigate the hypothesis that a similar T-cell process may be involved in both antimitochondrial antibody-positive and -negative primary biliary cirrhosis, we characterized the oligoclonally expanded T cells in both types of patients by analysis of complementarity determining region 3 length in peripheral blood mononuclear cells. The distribution of oligoclonally expanded T cells was similar in both groups. This finding does not support a distinct T-cell-mediated pathogenesis for anti-mitochondrial antibody-positive and -negative primary biliary cirrhosis but rather suggests that similar processes may be involved in the immunopathogenesis of both.

The epidemiology of melioidosis in Australia and Papua New Guinea.

Melioidosis was first described in Australia in an outbreak in sheep in 1949 in north Queensland (22 degrees S). Human melioidosis was first described from Townsville (19 degrees S) in 1950. Melioidosis is hyperendemic in the Top End of the Northern Territory (NT) and as in parts of northeastern Thailand it is the commonest cause of fatal community-acquired septicemic pneumonia. In the 9 years since 1989 the prospective NT melioidosis study at Royal Darwin Hospital (12 degrees S) has documented 206 culture confirmed cases of melioidosis, with an average annual incidence of 16.5/100,000. Melioidosis is also seen in the north of Western Australia and north Queensland, including the Torres Strait Islands, but is uncommon in adjacent Papua New Guinea. Serological studies suggest that infection is rare in the Port Moresby region, but there is emerging evidence of melioidosis from Western Province. The NT study has documented inoculating events in 52 (25%) of cases, with an incubation period of 1-21 days (mean 9 days); 84% of cases had acute disease from presumed recent acquisition and 13% had chronic disease (sick, > 2 months). In 4% there was evidence of possible reactivation from a latent focus; 28 of 153 (18%) males had prostatic abscesses. The overall mortality was 21% (43 cases), with a mortality rate in septicemic cases (95) of 39% and in non-septicemic cases (103) of 4%. Pneumonia was the commonest presentation in both groups and, in addition, eight patients (two deaths) presented with melioidosis encephalomyelitis. Melioidosis clusters in temperate Australia are attributed to animals imported from the north. Molecular typing of Burkholderia pseudomallei isolates from temperate southwest Western Australia showed clonality over 25 years. In this outbreak and in studies from the NT, some soil isolates are molecularly identical to epidemiologically related animal and human isolates. Molecular typing has implicated the water supply in two clonal outbreaks in remote aboriginal communities in northern Australia. Further prospective collaborative studies are required to evaluate whether there are truly regional differences in clinical features of melioidosis and to better understand how B. pseudomallei is acquired from the environment.

Association of clonally expanded T cells with the syndrome of primary biliary cirrhosis and limited scleroderma.

Clinical features of the CREST (calcinosis cutis, Raynaud's syndrome, esophageal dysmotility, sclerodactyly, and telangiectasias) syndrome are sometimes exhibited in patients with primary biliary cirrhosis (PBC), but the postulated autoimmune mechanisms behind these conditions are poorly understood. Clonally expanded T cells may play an important role in disease pathogenesis. In this study, overrepresentation of one T-cell receptor beta chain variable region, TCRBV3, was documented in patients with PBC and/or CREST. Overrepresentation of the TCRBV3 gene mRNA was demonstrated by semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). T cells expressing TCRBV3 were analyzed by flow cytometry, were primarily CD8(+), and contained activated cells as assessed by expression of CD69. Clonally expanded T cells within this population were documented by both complementarity determining region 3 (CDR3) length polymorphism analysis and sequencing of T-cell receptor CDR3 cDNA. TCRBV3(+) clonal expansions were stable when followed for up to 5 years. The results of this study demonstrate that the T-cell repertoire of patients with PBC and CREST is characterized by expanded clonal populations of CD8(+) TCRBV3(+) T cells. These clonal expansions provide evidence that stimulation of clonal populations of CD8(+) T cells is associated with the clinical syndrome of PBC with CREST.

T-cell receptor Vbeta gene utilization in primary biliary cirrhosis.

Semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR) was used to study the T-cell receptor (TCR) beta-chain variable (Vbeta) region gene families expressed by T cells in 28 patients with primary biliary cirrhosis (PBC), 20 normal controls, and 9 patients with other chronic inflammatory hepatic diseases. We hypothesized that activation and clonal proliferation of T cells would lead to biases in the T-cell repertoire of patients with PBC. Freshly harvested T cells from both peripheral blood and liver tissue were examined for evidence of biased Vbeta utilization. Individuals varied considerably in their pattern of Vbeta expression, but several significant differences were noted in the PBC group. In peripheral blood, the mean level of Vbeta6.1,3 expression was greater in PBC patients than in normal controls. In the liver of PBC patients, the mean level of Vbeta6.1,3 expression was even higher than in the peripheral blood, indicating intrahepatic accumulation of these T cells. The mean level of Vbeta6.1,3 expression was not significantly different in the blood compared with liver in patients with other liver diseases. Expression of Vbeta7 and Vbeta13.1 was also significantly greater in the liver than in the blood of PBC patients, but similar trends were also seen in the control liver group. These data show that specific alterations in the TCR repertoire are present in the blood and liver of patients with PBC.

Temperature and Thermal Emissivity of the Surface of Neptune's Satellite Triton.

Analysis of the preliminary results from the Voyager mission to the Neptune system has provided the scientific community with several methods by which the temperature of Neptune's satellite Triton may be determined. If the 37.5 K surface temperature reported by several Voyager investigations is correct, then the photometry reported by the imaging experiment on Voyager requires that Triton's surface have a remarkably low emissivity. Such a low emissivity is not required in order to explain the photometry from the photopolarimeter experiment on Voyager. A low emissivity would be inconsistent with Triton having a rough surface at the approximately 100-microm scale as might be expected given the active renewal processes which appear to dominate Triton's surface.

Deletion mutation as a means of isolating avirulence genes in flax rust.

The interaction between flax rust,Melampsora lini, and its host, flax,Linum usitatissimum, has been extensively studied, and certain genetic features make the system an appropriate choice to utilize in isolating genes conferring avirulence in rust. A mutant that was selected for virulence on Lx plants was isolated, after treatment with gamma rays, from a strain that is genotypicallyA-L5,A-L6,A-L7,A-Lx/A-L5,A-L6,a-L7,a-Lx. These four specificities are tightly linked. Breeding tests showed that this mutant was genotypicallyA-L5,A-L6,a-L7,a-Lx/a-L5,a-L6,a-L7,a-Lx and, when made homozygous for the mutant chromosome, was virulent onL5,L6,L7, andLx. This result excludes somatic recombination as a source of the mutation and indicates deletion as a likely cause. A 250 bp genomic sequence from a strain of rust homozygous for these four linked avirulence genes (A-L5,A-L6,A-L7,A-Lx) was isolated, using a method that allows the differential cloning of the specific DNA sequences located within a deletion in the mutant genome. This clone hybridized to two EcoRI bands in genomic DNA from the strain homozygous for the four linked avirulence genes and from the strain homozygousA-L5 andA-L6 and heterozygousA-L7 andA-Lx, but showed no homology to DNA from the strain carrying the putative chromosomal deletion. The correlation between the genetically characterized deletion mutation and the isolation of a sequence from within a region of chromosome missing from this strain of rust suggests that this 250 bp tract may be part of, or closely linked to, the defined set of avirulence genes.

Photometry from voyager 2: initial results from the neptunian atmosphere, satellites, and rings.

The Voyager photopolarimeter successfully accomplished its objectives for the Neptune encounter, performing measurements on the planet, several of its satellites, and its ring system. A photometric map of Neptune at 0.26 micrometer (microm) shows the planet to be bland, with no obvious contrast features. No polar haze was observed. At 0.75 microm, contrast features are observed, with the Great Dark Spot appearing as a low-albedo region and the bright companion as being substantially brighter than its surroundings, implying it to be at a higher altitude than the Great Dark Spot. Triton's linear phase coefficients of 0.011 magnitudes per degree at 0.26 microm and 0.013 magnitudes per degree at 0.75 microm are consistent with a solid-surface object possessing high reflectivity. Preliminary geometric albedos for Triton, Nereid, and 1989N2 were obtained at 0.26 and 0.75 microm. Triton's rotational phase curve shows evidence of two major compositional units on its surface. A single stellar occultation of the Neptune ring system elucidated an internal structure in 1989N1R, in the approximately 50-kilometer region of modest optical depth. 1989N2R may have been detected. The deficiency of material in the Neptune ring system, when compared to Uranus', may imply the lack of a "recent" moon-shattering event.