261 research outputs found

    Multi-parallel qPCR provides increased sensitivity and diagnostic breadth for gastrointestinal parasites of humans: field-based inferences on the impact of mass deworming

    Get PDF
    BACKGROUND: Although chronic morbidity in humans from soil transmitted helminth (STH) infections can be reduced by anthelmintic treatment, inconsistent diagnostic tools make it difficult to reliably measure the impact of deworming programs and often miss light helminth infections. METHODS: Cryopreserved stool samples from 796 people (aged 2-81 years) in four villages in Bungoma County, western Kenya, were assessed using multi-parallel qPCR for 8 parasites and compared to point-of-contact assessments of the same stools by the 2-stool 2-slide Kato-Katz (KK) method. All subjects were treated with albendazole and all Ascaris lumbricoides expelled post-treatment were collected. Three months later, samples from 633 of these people were re-assessed by both qPCR and KK, re-treated with albendazole and the expelled worms collected. RESULTS: Baseline prevalence by qPCR (n = 796) was 17 % for A. lumbricoides, 18 % for Necator americanus, 41 % for Giardia lamblia and 15% for Entamoeba histolytica. The prevalence was <1% for Trichuris trichiura, Ancylostoma duodenale, Strongyloides stercoralis and Cryptosporidium parvum. The sensitivity of qPCR was 98% for A. lumbricoides and N. americanus, whereas KK sensitivity was 70% and 32%, respectively. Furthermore, qPCR detected infections with T. trichiura and S. stercoralis that were missed by KK, and infections with G. lamblia and E. histolytica that cannot be detected by KK. Infection intensities measured by qPCR and by KK were correlated for A. lumbricoides (r = 0.83, p < 0.0001) and N. americanus (r = 0.55, p < 0.0001). The number of A. lumbricoides worms expelled was correlated (p < 0.0001) with both the KK (r = 0.63) and qPCR intensity measurements (r = 0.60). CONCLUSIONS: KK may be an inadequate tool for stool-based surveillance in areas where hookworm or Strongyloides are common or where intensity of helminth infection is low after repeated rounds of chemotherapy. Because deworming programs need to distinguish between populations where parasitic infection is controlled and those where further treatment is required, multi-parallel qPCR (or similar high throughput molecular diagnostics) may provide new and important diagnostic information

    Resonant X-ray Scattering in Manganites - Study of Orbital Degree of Freedom -

    Full text link
    Orbital degree of freedom of electrons and its interplay with spin, charge and lattice degrees of freedom are one of the central issues in colossal magnetoresistive manganites. The orbital degree of freedom has until recently remained hidden, since it does not couple directly to most of experimental probes. Development of synchrotron light sources has changed the situation; by the resonant x-ray scattering (RXS) technique the orbital ordering has successfully been observed . In this article, we review progress in the recent studies of RXS in manganites. We start with a detailed review of the RXS experiments applied to the orbital ordered manganites and other correlated electron systems. We derive the scattering cross section of RXS where the tensor character of the atomic scattering factor (ASF) with respect to the x-ray polarization is stressed. Microscopic mechanisms of the anisotropic tensor character of ASF is introduced and numerical results of ASF and the scattering intensity are presented. The azimuthal angle scan is a unique experimental method to identify RXS from the orbital degree of freedom. A theory of the azimuthal angle and polarization dependence of the RXS intensity is presented. The theoretical results show good agreement with the experiments in manganites. Apart from the microscopic description of ASF, a theoretical framework of RXS to relate directly to the 3d orbital is presented. The scattering cross section is represented by the correlation function of the pseudo-spin operator for the orbital degree of freedom. A theory is extended to the resonant inelastic x-ray scattering and methods to observe excitations of the orbital degree of freedom are proposed.Comment: 47 pages, 24 figures, submitted to Rep. Prog. Phy

    Accreting Millisecond X-Ray Pulsars

    Full text link
    Accreting Millisecond X-Ray Pulsars (AMXPs) are astrophysical laboratories without parallel in the study of extreme physics. In this chapter we review the past fifteen years of discoveries in the field. We summarize the observations of the fifteen known AMXPs, with a particular emphasis on the multi-wavelength observations that have been carried out since the discovery of the first AMXP in 1998. We review accretion torque theory, the pulse formation process, and how AMXP observations have changed our view on the interaction of plasma and magnetic fields in strong gravity. We also explain how the AMXPs have deepened our understanding of the thermonuclear burst process, in particular the phenomenon of burst oscillations. We conclude with a discussion of the open problems that remain to be addressed in the future.Comment: Review to appear in "Timing neutron stars: pulsations, oscillations and explosions", T. Belloni, M. Mendez, C.M. Zhang Eds., ASSL, Springer; [revision with literature updated, several typos removed, 1 new AMXP added

    Retroperitoneal abscess complicated with necrotizing fasciitis of the thigh in a patient with sigmoid colon cancer

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Necrotizing fasciitis of the thigh due to the colon cancer, especially during chemotherepy, has not been previously reported.</p> <p>Case presentation</p> <p>A 67-year-old man admitted to the hospital was diagnosed with sigmoid colon cancer that had spread to the left psoas muscle. Multiple hepatic metastases were also found, and combination chemotherapy with irinotecan and S-1 was administered. Four months after the initiation of chemotherapy, the patient developed gait disturbance and high fever and was therefore admitted to the emergency department of our hospital. Blood examination revealed generalized inflammation with a high C-reactive protein level. Computed tomography of the abdomen and pelvis showed gas and fluid collection in the retroperitoneum adjacent to the sigmoid colon cancer. The abscess was locally drained under computed tomographic guidance; however, the infection continued to spread and necrotizing fasciitis developed. Consequently, emergent debridement was performed. The patient recovered well, and the primary tumor was resected after remission of the local inflammation.</p> <p>Conclusion</p> <p>Necrotizing fasciitis of the thigh due to the spread of sigmoid colon cancer is unusual, but this fatal complication should be considered during chemotherapy for patients with unresectable colorectal cancer.</p

    Epidermal Growth Factor Receptor (EGFR) gene copy number (GCN) correlates with clinical activity of irinotecan-cetuximab in K-RAS wild-type colorectal cancer: a fluorescence in situ (FISH) and chromogenic in situ hybridization (CISH) analysis

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>K-RAS wild type colorectal tumors show an improved response rate to anti-EGFR monoclonal antibodies. Nevertheless 70% to 40% of these patients still does not seem to benefit from this therapeutic approach. FISH EGFR GCN has been previously demonstrated to correlate with clinical outcome of colorectal cancer treated with anti-EGFR monoclonal antibodies. CISH also seemed able to provide accurate EGFR GCN information with the advantage of a simpler and reproducible technique involving immunohistochemistry and light microscopy. Based on these findings we investigated the correlation between both FISH and CISH EGFR GCN and clinical outcome in K-RAS wild-type colorectal cancer treated with irinotecan-cetuximab.</p> <p>Methods</p> <p>Patients with advanced K-RAS wild-type, colorectal cancer receiving irinotecan-cetuximab after failure of irinotecan-based chemotherapy were eligible.</p> <p>A cut-off value for EGFR GCN of 2.6 and 2.12 for FISH and CISH respectively was derived from ROC curve analysis.</p> <p>Results</p> <p>Forty-four patients were available for analysis. We observed a partial remission in 9 (60%) and 2 (9%) cases with a FISH EGFR GCN ≥ 2.6 and < 2.6 respectively (p = 0.002) and in 10 (36%) and 1 (6%) cases with a CISH EGFR GCN ≥ 2.12 and < 2.12 respectively (p = 0.03). Median TTP was 7.7 and 6.4 months in patients showing increased FISH and CISH EGFR GCN whereas it was 2.9 and 3.1 months in those with low FISH and CISH EGFR GCN (p = 0.04 and 0.02 respectively).</p> <p>Conclusion</p> <p>FISH and CISH EGFR GCN may both represent effective tools for a further patients selection in K-RAS wild-type colorectal cancer treated with cetuximab.</p

    Measuring enteric methane emissions from individual ruminant animals in their natural environment

    Get PDF
    Ruminant livestock are an important source of meat, milk, fiber, and labor for humans. The process by which ruminants digest plant material through rumen fermentation into useful product results in the loss of energy in the form of methane gas from consumed organic matter. The animal removes the methane building up in its rumen by repeated eructations of gas through its mouth and nostrils. Ruminant livestock are a notable source of atmospheric methane, with an estimated 17% of global enteric methane emissions from livestock. Historically, enteric methane was seen as an inefficiency in production and wasted dietary energy. This is still the case, but now methane is seen more as a pollutant and potent greenhouse gas. The gold standard method for measuring methane production from individual animals is a respiration chamber, which is used for metabolic studies. This approach to quantifying individual animal emissions has been used in research for over 100 years; however, it is not suitable for monitoring large numbers of animals in their natural environment on commercial farms. In recent years, several more mobile monitoring systems discussed here have been developed for direct measurement of enteric methane emissions from individual animals. Several factors (diet composition, rumen microbial community, and their relationship with morphology and physiology of the host animal) drive enteric methane production in ruminant populations. A reliable method for monitoring individual animal emissions in large populations would allow (1) genetic selection for low emitters, (2) benchmarking of farms, and (3) more accurate national inventory accounting

    Phase II study of a triplet regimen in advanced colorectal cancer using methotrexate, oxaliplatin and 5-fluorouracil

    Get PDF
    Building upon the concept of schedule-specific biochemical modulation of 5-fluorouracil (FU), which alternates bolus and continuous infusion (CI) FU, we have incorporated oxaliplatin (l-OHP) following the bolus part of the regimen to explore the activity of this new combination. Patients with advanced, untreated, measurable colorectal cancer received sequential methotrexate (MTX) (days 1 and 15)-->l-OHP+FU (days 2 and 16) (200, 85 and 600 mg m(-2), respectively) followed by 3 weeks of CI FU (200 mg m(-2) day(-1)) given from day 29 to 50, modulated by weekly leucovorin (LV) (20 mg m(-2)). After 1 week of rest, the second cycle was started. The treatment was continued until progression or patient's refusal. According to the intention-to-treat analysis on all 46 patients accrued, the response rate was 42% (95% CL=28-55%), with three complete responses and 16 partial responses. The median overall survival was 15.9 months and the median progression-free survival 6.9 months. Toxicity was very mild, with the bolus part of the regimen more toxic than the infusional part (24 vs 7% of grade III-IV, respectively). This new combination of MTX -->l-OHP-FU followed by FU CI is well tolerated, feasible and produces activity results similar to other more simple, but more toxic, regimens. Pros and cons of the different fluoropyrimidines-l-OHP combinations are discussed

    Breast Cancer Stem-Like Cells Are Inhibited by a Non-Toxic Aryl Hydrocarbon Receptor Agonist

    Get PDF
    Cancer stem cells (CSCs) have increased resistance to cancer chemotherapy. They can be enriched as drug-surviving CSCs (D-CSCs) by growth with chemotherapeutic drugs, and/or by sorting of cells expressing CSC markers such as aldehyde dehydrogenase-1 (ALDH). CSCs form colonies in agar, mammospheres in low-adherence cultures, and tumors following xenotransplantation in Scid mice. We hypothesized that tranilast, a non-toxic orally active drug with anti-cancer activities, would inhibit breast CSCs.We examined breast cancer cell lines or D-CSCs generated by growth of these cells with mitoxantrone. Tranilast inhibited colony formation, mammosphere formation and stem cell marker expression. Mitoxantrone-selected cells were enriched for CSCs expressing stem cell markers ALDH, c-kit, Oct-4, and ABCG2, and efficient at forming mammospheres. Tranilast markedly inhibited mammosphere formation by D-CSCs and dissociated formed mammospheres, at pharmacologically relevant concentrations. It was effective against D-CSCs of both HER-2+ and triple-negative cell lines. Tranilast was also effective in vivo, since it prevented lung metastasis in mice injected i.v. with triple-negative (MDA-MB-231) mitoxantrone-selected cells. The molecular targets of tranilast in cancer have been unknown, but here we demonstrate it is an aryl hydrocarbon receptor (AHR) agonist and this plays a key role. AHR is a transcription factor activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), polycyclic aromatic hydrocarbons and other ligands. Tranilast induced translocation of the AHR to the nucleus and stimulated CYP1A1 expression (a marker of AHR activation). It inhibited binding of the AHR to CDK4, which has been linked to cell-cycle arrest. D-CSCs expressed higher levels of the AHR than other cells. Knockdown of the AHR with siRNA, or blockade with an AHR antagonist, entirely abrogated the anti-proliferative and anti-mammosphere activity of tranilast. Thus, the anti-cancer effects of tranilast are AHR dependent.We show that tranilast is an AHR agonist with inhibitory effects on breast CSCs. It is effective against CSCs of triple-negative breast cancer cells selected for anti-cancer drug resistance. These results suggest it might find applications in the treatment of breast cancer

    Bevacizumab plus FOLFIRI or FOLFOX in chemotherapy-refractory patients with metastatic colorectal cancer: a retrospective study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The anti-VEGF antibody bevacizumab associated with an irinotecan or oxaliplatin-based chemotherapy was proved to be superior to the chemotherapy alone in first or second line treatment of metastatic colorectal cancer (mCRC). However, it was reported to have no efficacy in 3<sup>rd </sup>or later-line, alone or with 5FU. The aim of this study was to evaluate the activity of bevacizumab combined with FOLFIRI or FOLFOX in mCRC who have failed prior chemotherapy with fluoropyrimidine plus irinotecan and/or oxaliplatin.</p> <p>Methods</p> <p>Thirty one consecutive patients treated between May 2005 and October 2006 were included in this retrospective study. All of them have progressed under a chemotherapy with fluoropyrimidine plus irinotecan and/or oxaliplatin and received bevacizumab (5 mg/kg) in combination with FOLFIRI or simplified FOLFOX4 every 14 days.</p> <p>Results</p> <p>Ten patients (32.2%) had an objective response (1 CR, 9 PR) and 12 (38.8%) were stabilized. The response and disease control rates were 45.4% and 100% when bevacizumab was administered in 2<sup>nd </sup>or 3<sup>rd </sup>line and 25% and 55% in 4<sup>th </sup>or later line respectively (p = 0.024 and p = 0.008). Among the patients who had previously received the same chemotherapy than that associated with bevacizumab (n = 28) the overall response rate was 35.7% and 39.3% were stabilized. Median progression free survival (PFS) and overall survival (OS) were of 9.7 and 18.4 months respectively. Except a patient who presented a hypertension associated reversible posterior leukoencephalopathy syndrome, tolerance of bevacizumab was acceptable. A rectal bleeding occurred in one patient, an epistaxis in five. Grade 1/2 hypertension occurred in five patients.</p> <p>Conclusion</p> <p>This study suggests that bevacizumab combined with FOLFOX or FOLFIRI may have the possibility to be active in chemorefractory and selected mCRC patients who did not receive it previously.</p
    • …
    corecore