Imaging Correlations in Heterodyne Spectra for Quantum Displacement Sensing

The extraordinary sensitivity of the output field of an optical cavity to small quantum-scale displacements has led to breakthroughs such as the first detection of gravitational waves and of the motions of quantum ground-state cooled mechanical oscillators. While heterodyne detection of the output optical field of an optomechanical system exhibits asymmetries which provide a key signature that the mechanical oscillator has attained the quantum regime, important quantum correlations are lost. In turn, homodyning can detect quantum squeezing in an optical quadrature but loses the important sideband asymmetries. Here we introduce and experimentally demonstrate a new technique, subjecting the autocorrelators of the output current to filter functions, which restores the lost heterodyne correlations (whether classical or quantum), drastically augmenting the useful information accessible. The filtering even adjusts for moderate errors in the locking phase of the local oscillator. Hence we demonstrate the single-shot measurement of hundreds of different field quadratures allowing the rapid imaging of detailed features from a simple heterodyne trace. We also obtain a spectrum of hybrid homodyne-heterodyne character, with motional sidebands of combined amplitudes comparable to homodyne. Although investigated here in a thermal regime, the method's robustness and generality represents a promising new approach to sensing of quantum-scale displacements.

Straight-to-test colonoscopy for 2-week-wait referrals improves time to diagnosis of colorectal cancer and is feasible in a high-volume unit

AIM

We have introduced 'straight-to-test' (STT) colonoscopy as part of our 2-week-wait (2WW) pathway to address increasing numbers of urgent referrals for colorectal cancer (CRC) within the National Health Service. In this study we evaluated the ability of this initiative to shorten the time to diagnosis of CRC.

METHOD

We amended our 2WW referral form to include performance status and comorbidities. General practitioners were asked to provide data on estimated glomerular filtration rate and full blood count/ferritin. Our 2WW referrals were screened by a colorectal consultant and a nurse specialist. Those deemed unsuitable for STT were offered outpatient assessment (OPA).

RESULTS

Of 553 2WW referrals screened, 352 were considered suitable, 65 of whom failed a telephone assessment or were uncontactable, and accordingly 287 were offered the STT pathway. The STT group was significantly younger than the OPA group (median 65.9 years vs 78.7 years; P < 0.0001). STT colonoscopy significantly reduced the time to first test (13 days vs 22 days; P < 0.0001) and tissue diagnosis from the referral date (17 days vs 24.5 days; P < 0.0001). Thirty-seven (6.8%) CRCs were detected. Proportionately fewer patients in the STT pathway were managed with 'best supportive care only' compared with patients attending OPA (one of 15 vs six of 22, respectively). STT colonoscopy obviated the need for clinic attendance before testing in 287 patients, representing a potential net cost benefit of at least £48 500 in 4 months.

CONCLUSION

STT colonoscopy was safe and effective for selecting out a group of symptomatic patients who could proceed straight to endoscopic examination and receive a diagnosis more rapidly.

Sofosbuvir plus ribavirin in treatment-naïve patients with chronic hepatitis C virus genotype 1 or 3 infection in India

Until 2014, pegylated interferon plus ribavirin was the recommended standard of care for the treatment of chronic hepatitis C virus (HCV) infection in India. This open-label phase 3b study, conducted across 14 sites in India between 31 March 2014 and 30 November 2015, evaluated the efficacy and safety of sofosbuvir plus ribavirin therapy among treatment-naïve patients with chronic genotype 1 or 3 HCV infection. A total of 117 patients with genotype 1 or 3 HCV infection were randomized 1:1 to receive sofosbuvir 400 mg and weight-based ribavirin (1000 or 1200 mg) daily for 16 or 24 weeks. Among those with genotype 1 infection, the primary efficacy endpoint of sustained virologic response at 12 weeks post-treatment (SVR12) was reported in 90% (95% confidence intervals [CI], 73-98) and 96% (95% CI, 82-100) of patients following 16 and 24 weeks of treatment, respectively. For patients with genotype 3 infection, SVR12 rates were 100% (95% CI, 88-100) and 93% (95% CI, 78-99) after 16 and 24 weeks of therapy, respectively. Adverse events, most of which were mild or moderate in severity, occurred in 69% and 57% of patients receiving 16 and 24 weeks of treatment, respectively. The most common treatment-emergent adverse events were asthenia, headache and cough. Only one patient in the 24-week group discontinued treatment with sofosbuvir during this study. Overall, sofosbuvir plus ribavirin therapy achieved SVR12 rates ≥90% and was well tolerated among treatment-naïve patients with chronic genotype 1 or 3 HCV infection in India.

Rice Vision for Bangladesh: 2050 and Beyond

CORRECTION: Due to a number of formatting and layout issues, the PDF of this paper was replaced on 10th October 2016.Combined efforts of farmers, rice scientists, extension personnel and Government of Bangladesh have yielded clean rice growth rate of 0.34 million ton (MT) year-1 during 2009-10 to 2013-14 in the country. In 2014-15, the country acquired a rice surplus of about 2 MT. However, maintaining the current surplus of rice in the coming decades is a great challenge. Authentic estimation of future rice requirement and future resource availability would guide to way forward. This paper presents rice vision for Bangladesh leading to 2050 and beyond. In this study, secondary data from different government-owned statistics and research institutes were collected, analyzed and synthesized to develop models and/or model parameters to generate outputs such as future population, rice production and rice requirement. Population of Bangladesh will reach 215.4 million in 2050, when 44.6 MT of clean rice will be required. With the pace of rice-production-increase in the last five years, production can reach 47.2 MT, having a surplus of 2.6 MT in 2050. The study sets 2.6 MT as the target for clean rice surplus every year leading to 2050 and beyond. Several hurdles, such as increasing population, decreasing resources and increasing climate vulnerability, can hinder achieving the target. Three major interventions?accelerating genetic gain, minimizing yield gap and curtailing adoption lag?are proposed to break the barriers to achieve the target. Major challenges to implement the interventions include shrinking net cropped area, decreasing availability of irrigation water and increasing pressure on soil fertility. Smart technology such as, location specific variety, profitable cropping sequences, innovative cultural management, and mechanization coupled with smart dissemination using multiple means would ease production barriers. We recommend a number of measures, such as, guaranteeing a minimum cropped area, accelerating the rate of genetic gain in varietal development and intensifying collaboration among the stakeholders to reduce adoption lag of newly released promising rice varieties, to achieve the rice vision of Bangladesh leading to 2050 and beyond.Bangladesh Rice j. 2015, 19(2): 1-18

Natural killer cells contribute to hepatic injury and help in viral persistence during progression of hepatitis B e-antigen-negative chronic hepatitis B virus infection

Hepatitis B e-antigen negative (e(-)) chronic HBV infection (CHI) encompasses a heterogeneous clinical spectrum ranging from inactive carrier (IC) state to e(-) chronic hepatitis B (CHB), cirrhosis and hepatic decompensation. In the backdrop of dysfunctional virus-specific T cells, natural killer (NK) cells are emerging as innate effectors in CHI. We characterized CD3(-) CD56(+) NK cells in clinically well-defined, treatment-naive e(-) patients in IC, e(-)CHB or decompensated liver cirrhosis (LC) phase to appraise their role in disease progression. The NK cell frequencies increased progressively with disease severity (IC 8.2%, e(-)CHB 13.2% and LC 14.4%). Higher proportion of NK cells from LC/e(-)CHB expressed CD69, NKp46, NKp44, TRAIL and perforin, the last two being prominent features of CD56(bright) and CD56(dim) NK subsets, respectively. The frequencies of CD3(-) CD56(+) NK cells together with TRAIL(+) CD56(bright) and Perforin(+) CD56(dim) NK cells correlated positively with serum alanine transaminase levels in e(-)CHB/LC. K562 cell-stimulated NK cells from e(-)CHB/LC exhibited significantly greater degranulation but diminished interferon-γ production than IC. Further, Perforin(+) NK cell frequency inversely correlated with autologous CD4(+) T-cell count in e(-) patients and ligands of NK receptors were over-expressed in CD4(+) T cells from e(-)CHB/LC relative to IC. Co-culture of sorted CD56(dim) NK cells and CD4(+) T cells from e(-)CHB showed enhanced CD4(+) T-cell apoptosis, which was reduced by perforin inhibitor, concanamycin A, suggesting a possible perforin-dependent NK cell-mediated CD4(+) T-cell depletion. Moreover, greater incidence of perforin-expressing NK cells and decline in CD4(+) T cells were noticed intrahepatically in e(-)CHB than IC. Collectively, NK cells contribute to the progression of e(-)CHI by enhanced TRAIL- and perforin-dependent cytolytic activity and by restraining anti-viral immunity through reduced interferon-γ secretion and perforin-mediated CD4(+) T-cell lysis.

Synthesis of rare-earth doped ZnO nanorods and their defect–dopant correlated enhanced visible-orange luminescence

Rare-earth doped sub-10 nm diameter ZnO nanorods show defect–dopant assisted enhanced visible-orange luminescence and also display multicolour rare-earth emission.

Interaction of α-crystallin with some small molecules and its effect on its structure and function

BACKGROUND

α-Crystallin acts like a molecular chaperone by interacting with its substrate proteins and thus prevents their aggregation. It also interacts with various kinds of small molecules that affect its structure and function.

SCOPE OF REVIEW

In this article we will present a review of work done with respect to the interaction of ATP, peptide generated from lens crystallin and other proteins and some bivalent metal ions with α-crystallin and discuss the role of these interactions on its structure and function and cataract formation. We will also discuss the interaction of some hydrophobic fluorescence probes and surface active agents with α-crystallin.

MAJOR CONCLUSIONS

Small molecule interaction controls the structure and function of α-crystallin. ATP and Zn+2 stabilize its structure and enhance chaperone function. Therefore the depletion of these small molecules can be detrimental to maintenance of lens transparency. However, the accumulation of small peptides due to protease activity in the lens can also be harmful as the interaction of these peptides with α-crystallin and other crystallin proteins in the lens promotes aggregation and loss of lens transparency. The use of hydrophobic probe has led to a wealth of information regarding the location of substrate binding site and nature of chaperone-substrate interaction. Interaction of surface active agents with α-crystallin has helped us to understand the structural stability and oligomeric dissociation in α-crystallin.

GENERAL SIGNIFICANCE

These interactions are very helpful in understanding the mechanistic details of the structural changes and chaperone function of α-crystallin. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease.

General practice performance in referral for suspected cancer: influence of number of cases and case-mix on publicly reported data

Background:

Publicly available data show variation in GPs' use of urgent suspected cancer (USC) referral pathways. We investigated whether this could be due to small numbers of cancer cases and random case-mix, rather than due to true variation in performance.

Methods:

We analysed individual GP practice USC referral detection rates (proportion of the practice's cancer cases that are detected via USC) and conversion rates (proportion of the practice's USC referrals that prove to be cancer) in routinely collected data from GP practices in all of England (over 4 years) and northeast Scotland (over 7 years). We explored the effect of pooling data. We then modelled the effects of adding random case-mix to practice variation.

Results:

Correlations between practice detection rate and conversion rate became less positive when data were aggregated over several years. Adding random case-mix to between-practice variation indicated that the median proportion of poorly performing practices correctly identified after 25 cancer cases were examined was 20% (IQR 17 to 24) and after 100 cases was 44% (IQR 40 to 47).

Conclusions:

Much apparent variation in GPs' use of suspected cancer referral pathways can be attributed to random case-mix. The methods currently used to assess the quality of GP-suspected cancer referral performance, and to compare individual practices, are misleading. These should no longer be used, and more appropriate and robust methods should be developed.

Immune-driven adaptation of hepatitis B virus genotype D involves preferential alteration in B-cell epitopes and replicative attenuation--an insight from human immunodeficiency virus/hepatitis B virus coinfection

An important driving force behind the sequence diversity of hepatitis B virus (HBV) is viral adaptation to host immune responses. To gain an insight into the impact of host immunity on genetic diversification and properties of HBV, we characterized HBV of genotype D from treatment-naive hepatitis B e antigen-positive (EP) and hepatitis B e antigen-negative (EN) patients with chronic hepatitis B (CHB), where HBV is under stronger immune pressure, with that of HBV derived from human immunodeficiency virus (HIV)/HBV-coinfected individuals, where HIV infection has significantly weakened the immune system. Full-length sequence analysis showed that HBV heterogeneity was most extensive in EN-CHB followed by EP-CHB and HIV/HBV coinfection. The relative magnitude of non-synonymous changes within B-cell epitopes was greater than that in T-cell epitopes of HBV open reading frames (ORFs) in both EP-CHB and EN-CHB. Nine amino acid substitutions were identified in B-cell epitopes and one in a T-cell epitope of HBV in EN-CHB, most of which resulted in altered hydrophobicities, as determined using the Kyte and Doolittle method, relative to wild-type residues found in HBV from the HIV-positive group. Additionally, 19 substitutions occurred at significantly higher frequencies in non-epitope regions of HBV ORF-P in EN-CHB than HIV/HBV-coinfected patients. In vitro replication assay demonstrated that the substitutions, particularly in reverse transcriptase and RNaseH domains of ORF-P, resulted in a decline in replication capacity of HBV. Hence, our results indicate that HBV adapts to increasing immune pressure through preferential mutations in B-cell epitopes and by replicative attenuation. The viral epitopes linked to immune response identified in this study bear important implications for future HBV vaccine studies.

Methamphetamine induces low levels of neurogenesis in striatal neuron subpopulations and differential motor performance

Methamphetamine (METH) causes significant loss of some striatal projection and interneurons. Recently, our group reported on the proliferation of new cells 36 h after METH and some of the new cells survive up to 12 weeks (Tulloch et al., Neuroscience 193:162-169, 2011b). We hypothesized that some of these cells will differentiate and express striatal neuronal phenotypes. To test this hypothesis, mice were injected with METH (30 mg/kg) followed by a single BrdU injection (100 mg/kg) 36 h after METH. One week after METH, a population of BrdU-positive cells expressed the neuronal progenitor markers nestin (18 %) and β-III-tubulin (30 %). At 8 weeks, 14 % of the BrdU-positive cells were also positive for the mature neuron marker, NeuN. At 12 weeks, approximately 7 % of the BrdU-positive cells co-labeled with ChAT, PV or DARPP-32. We measured motor coordination on the rotarod and psychomotor activity in the open-field. At 12 weeks, METH-injected mice exhibited delayed motor coordination deficits. In contrast, open-field tests revealed that METH-injected mice compared to saline mice displayed psychomotor deficits at 2.5 days but not at 2 or more weeks after METH. Taken together, these data demonstrate that some of the new cells generated in the striatum differentiate and express the phenotypes of striatal neurons. However, the proportion of these new neurons is low compared to the proportion that died by apoptosis 24 h after the METH injection. More studies are needed to determine if the new neurons are functional.