Vertical cavity surface emitting terahertz laser

Vertical cavity surface emitting terahertz lasers can be realized in conventional semiconductor microcavities with embedded quantum wells in the strong coupling regime. The cavity is to be pumped optically at half the frequency of the 2p exciton state. Once a threshold population of 2p excitons is achieved, a stimulated terahertz transition populates the lower exciton-polariton branch, and the cavity starts emitting laser light both in the optical and terahertz ranges. The lasing threshold is sensitive to the statistics of photons of the pumping light.

Possibilistic risk management and counterfactual probabilities

Possibility theory is applied to assessing the relative risk associated with very rare, high-consequence hazards. The probability of rare negative events has to be estimated from a few past occurrences that are spread over long exposure periods, with countermeasures added in response to each event to attempt to guard against recurrence. Traditional risk assessments based on conditional probability and statistical expected value are very sensitive to the uncertainty associated with rare events. A new measure of possibility for events whose probability is not well measurably different from zero is proposed and illustrated in the context of possible release of hazardous material from a high containment research laboratory and in the context of large insurance company failures. Strategies for managing and reducing risk that do not depend on well-measured probabilities are discussed.

Biological Subtypes and Risk of Second Primary Breast Cancer in Inflammatory Breast Cancer – Population Based Analysis from the California Cancer Registry

Background: Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer. Our group's recent study revealed that the 5-year breast cancer specific survival for IBC is 49%, an improved rate compared to historical studies (∼ 30%). This could be attributed to evolution in modern modalities of treatment including utility of transtuzumab. Given marginally improved survival, these women are also at risk for second breast cancers. Here we investigate the risk of second breast cancer in IBC compared to the general population.Methods: We identified 75,039 IBC, LABC and non-T4 female breast cancer cases in the California Cancer Registry during the period of 1999-2005. We excluded synchronous tumors (cancer diagnosed <6 months from first breast cancer diagnosis). Standardized incidence ratio (SIR) with 95% CI is used to calculate the risk of second breast cancer by comparison to underlying general population.Results: A total of 1488 second breast cancer patients were identified, including 60 with a first diagnosis of IBC, 26 with a first diagnosis of LABC, and 1402 with a first diagnosis of non T-4 breast cancer. The risk of second breast cancer in IBC compared to the underlying population at risk was observed to be highest in IBC [SIR= 4.12 (3.14-5.30)] followed by LABC [SIR= 1.95 (1.28-2.86)], and non-T4 [SIR= 1.16 (1.10-1.23)] cases. Patients with IBC were more likely to be [HR-/HER2+] (43.8%) compared to LABC (33.3%) and non-T4 (8.7%) [p=<0.0001]. IBC and LABC were also increasingly associated with contralateral breast cancer (96%).Table-1: Risk of second breast cancer compared to general population by classification of first breast cancer Cohort sizeObserved 2nd breast cancerExpected 2nd breast cancerSIR (95%CI)IBC14746014.574.12 (3.14-5.30)LABC11032613.321.95 (1.28-2.86)Non-T472,46214021205.851.16 (1.10-1.23) Table-2: Hormone Receptor/Her2-neu status, subtype, laterality of second breast cancer by classification of first breast cancer £Receptor status of the first tumor*IBCLABCNon-T4TotalHR+/Her2+147(17%)123(20%)6405(15.5%)6675(15.7%)HR-/Her2+217(25%)98(16%)2713(6.6%)3028(7.1%)HR+/Her2-318(36.5%)268(43.8%)26,680(65%)27,266(64%)HR-/Her2-187(21.5%)124(20.2%)5303(12.9%)5614(13.2%)Receptor status of the second tumor**    HR+/Her2+2 (6.2%)4 (26.7%)97 (12.6%)103 (12.6%)HR-/Her2+14 (43.8%)5 (33.3%)67 (8.7%)86 (10.5%)HR+/Her2-11 (34.4%)6 (40%)468 (60.6%)485 (59.2%)HR-/Her2-5 (15.6%)0 (0%)140 (18.1%)145 (17.7%)Subtypes of the 2nd primary breast tumor***   OtherIBC11(18.3%)2(5%)13(21.7%)33(55%)LABC5(19%)1(4%)11(42.4%)9(34.6%)Non-T425(1.8%)8(0.5%)482(34.4%)887(63.2%)Contralateral Breast cancer58(96.6%)25(96.1%)1165(83%)1484£ p value <0.0001 for all comparisons, *43% of data missing;** 49% of data missing;*** 8% of data missing.Conclusions: HR-/HER2+ biologic subtype of IBC was increasingly associated with development of second breast cancers and majority of them (96%) involved the contralateral breast with possible implications for IBC treatment. Among the investigated breast cancer subtypes IBC was associated with the highest risk of second breast cancers compared to the underlying population reinforcing IBC as an unique biologic entity.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2056.

Radiological classification of optic pathway gliomas: experience of a modified functional classification system

Optic pathway gliomas (OPGs) in childhood are associated with neurofibromatosis type 1 (NF1) and since 1958 have been classified anatomically using the Dodge classification (DC). MR scanning permits a more detailed anatomical description than can be classified by this historical system. A modified Dodge classification (MDC) has been applied to MRI scans from a cohort of 72 patients (36.1% NF1-positive) from 4 centres participating in an international clinical trial. The MDC was feasible, applicable and more detailed than the original DC. NF1-positive cases more commonly involved both optic nerves (p = 0.021) and other multiple locations (p = 0.001). NF1-negative tumours more commonly involved the central chiasm (p = 0.005) and hypothalamus (p = 0.003). Fewer hypothalamus-positive tumours were associated with optic nerve involvement (p = 0.009), whereas more were associated with central chiasm involvement (p<0.001). From diagnosis to follow-up, there was concordance between DC and MDC in 51/72 cases (70.8%). The MDC is therefore proposed for use in clinical trials of new treatments for OPGs.

Elevation of IgA anti-epidermal transglutaminase antibodies in dermatitis herpetiformis

BACKGROUND

Dermatitis herpetiformis (DH) is a papulovesicular eruption caused by ingestion of gluten. It is characterized by the deposition of IgA in the dermal papillae. IgA antibodies directed at tissue transglutaminase (TG2) are elevated in gluten-sensitive diseases including DH and coeliac disease (CD). More recently, antibodies directed at epidermal transglutaminase (TG3) were identified in patients with DH, and this may be the dominant autoantigen in this disease.

OBJECTIVES

To measure IgA antibodies to TG3 and TG2 in patients with DH and CD, and control populations.

METHODS

Serum IgA antibodies against TG2 and TG3 were measured from adults with DH, adults and children with CD, patients with psoriasis, adult Red Cross blood donors, and paediatric controls.

RESULTS

Patients with DH and CD had elevated levels of IgA anti-TG2 antibodies compared with control populations. The levels in the patients with DH and adults with CD were similar. IgA anti-TG2 antibodies were higher in the children with CD compared with adults with DH and CD, and with control populations. Patients with DH and adults with CD had elevated levels of IgA anti-TG3 antibodies compared with children with CD and control populations. There was a trend towards higher levels in the patients with DH compared with adults with CD.

CONCLUSIONS

IgA antibodies to TG3 are elevated in patients with DH and adults with CD. The progressive expansion of the epitope-binding profile of IgA antitransglutaminase antibodies in patients with CD may explain the development of DH in patients with undiagnosed CD during their adult life.

Characterization of a Brucella sp. strain as a marine-mammal type despite isolation from a patient with spinal osteomyelitis in New Zealand

Naturally acquired infection of humans with a marine mammal-associated Brucella sp. has only been reported once previously in a study describing infections of two patients from Peru. We report the isolation and characterization of a strain of Brucella from a New Zealand patient that appears most closely related to strains previously identified from marine mammals. The isolate was preliminarily identified as Brucella suis using conventional bacteriological tests in our laboratory. However, the results profile was not an exact match, and the isolate was forwarded to four international reference laboratories for further identification. The reference laboratories identified the isolate as either B. suis or B. melitensis by traditional bacteriological methods in three laboratories and by a molecular test in the fourth laboratory. Molecular characterization by PCR, PCR-restriction fragment length polymorphism, and DNA sequencing of the bp26 gene; IS711; the omp genes omp25, omp31, omp2a, and omp2b; IRS-PCR fragments I, III, and IV; and five housekeeping gene fragments was conducted to resolve the discrepant identification of the isolate. The isolate was identified to be closely related to a Brucella sp. originating from a United States bottlenose dolphin (Tursiops truncatus) and common seals (Phoca vitulina).

[Ocular changes in tropical malaria with cerebral involvement--results from the Blantyre Malaria Project]

INTRODUCTION

Malaria is a tropical disease causing an estimated 300 million infections and one million deaths per year. In sub-Saharan Africa, most infections are due to Plasmodium falciparum. The hallmark of the clinical syndrome of cerebral malaria is coma, and the associated mortality rate, even in appropriately treated patients, is 15 - 50 %. Funduscopy plays a major role for the ophthalmologist in the differential diagnosis because of the characteristic changes.

METHODS

To date more than 1000 children who satisfied the standard clinical case definition of cerebral malaria were admitted to the Blantyre Malaria Project (Malawi, Africa) for inpatient treatment and examined using indirect ophthalmoscopy through fully dilated pupils. The gender distribution was homogeneous and the children were between 2 and 14 years old. The optic nerve head, central and peripheral retina and central and peripheral vessels were described and photographed using a hand-held fundus camera (KOWA).

RESULTS

The spectrum and severity of findings of the ocular fundus in children with CM include the following distinct entities: haemorrhages (with and without a white centre), cotton wool spots, papilloedema, retinal whitening and retinal vessel abnormalities that may appear to be orange or white. Most of the retinal haemorrhages (in 40 %) have white centres and resemble Roth spots. Cotton wool spots were seen in only 5 %. Papilloedema was also not commonly seen (8 %) but is a poor prognostic sign. Retinal whitening (in 50 %) is seen more commonly at the posterior pole than in the periphery. 20 % of patients show retinal vessel abnormalities that may be orange or white in colour.

CONCLUSION

Ocular fundus changes in CM can be detected by the ophthalmologist using simple means and are decisive for the prognosis and timely therapy for this potentially lethal disease.

Force transmission, compliance, and viscoelasticity are altered in the alpha7-integrin-null mouse diaphragm

Alpha7beta1 integrin is a transmembrane structural and receptor protein of skeletal muscles, and the absence of alpha7-integrin causes muscular dystrophy. We hypothesized that the absence of alpha7-integrin alters compliance and viscoelasticity and disrupts the mechanical coupling between passive transverse and axial contractile elements in the diaphragm. In vivo the diaphragm is loaded with pressure, and therefore axial and transverse length-tension relationships are important in assessing its function. We determined diaphragm passive length-tension relationships and the viscoelastic properties of its muscle in 1-month-old alpha7-integrin-null mice and age-matched controls. Furthermore, we measured the isometric contractile properties of the diaphragm from mutant and normal mice in the absence and presence of passive force applied in the transverse direction to fibers in 1-month-old and 5-month-old mutant mice. We found that compared with controls, the diaphragm direction of alpha7-integrin-null mutants showed 1) a significant decrease in muscle extensibility in 1-year-old mice, whereas muscle extensibility increased in the 1-month-old mice; 2) altered muscle viscoelasticity in the transverse direction of the muscle fibers of 1-month-old mice; 3) a significant increase in force-generating capacity in the diaphragms of 1-month-old mice, whereas in 5-month-old mice muscle contractility was depressed; and 4) significant reductions in mechanical coupling between longitudinal and transverse properties of the muscle fibers of 1-month-old mice. These findings suggest that alpha7-integrin serves an important mechanical function in the diaphragm by contributing to passive compliance, viscoelasticity, and modulation of its muscle contractile properties.

Implementation in Australia of molecular diagnostic techniques for the rapid detection of foot and mouth disease virus

OBJECTIVE

To evaluate and implement rapid molecular diagnostic techniques for the detection of foot and mouth disease virus (FMDV) suitable for use in Australia.

DESIGN

Two PCR TaqMan assays targeted to the FMDV internal ribosome entry site or the 3D polymerase coding region for the rapid detection of FMDV were evaluated using non-infectious materials to determine the test most appropriate for implementation as part of Australia's national preparedness for the rapid detection and diagnosis of FMD outbreaks.

RESULTS

Two published tests (PCR TaqMan assays targeted to the FMDV IRES region or the FMDV 3D polymerase coding region) were evaluated for their ability to detect FMDV genetic material in non-infectious FMDV ELISA antigen stocks held at Australian Animal Health Laboratory. Both tests were able to detect FMDV genetic material from strains O1 Manisa, O-3039, A22, A24, A Malaysia, C, Asia 1 and SAT 1, 2 and 3. With the exception of Asia 1, the TaqMan assay targeted to the FMD 3D polymerase coding region had Ct values equal to or lower than for the TaqMan assay targeted to the IRES region suggesting that this test may provide broader serotype detection and sensitivity. However, the TaqMan assay directed to the FMDV IRES is the only one to date to have undergone substantial evaluation using clinical samples collected during an outbreak. The greatest differences observed were for O-3039, SAT 1, and 3.

CONCLUSION

Given the ease of setting up both tests, AAHL currently runs both tests on highly suspect FMD investigations to provide independent confirmation of the absence of FMDV because the tests are focused on two independent regions of the FMDV genome. These tests add substantially to Australia's preparedness for FMD diagnosis complementing the already well-established virus isolation and antigen capture ELISA tests for index case diagnosis of FMD in Australia.