Comparison of 99mTc-sestamibi and doxorubicin to monitor inhibition of P-glycoprotein function

P-glycoprotein (Pgp) overexpression is a well-recognized factor in resistance to chemotherapy. Doxorubicin flow cytometry is used to monitor Pgp function in haematological specimens and biopsies from other cancers, and radionuclide imaging with sestamibi has recently shown promise for non-invasive monitoring. In the present study the two methods were directly compared in single-cell suspensions of three variants of the human breast carcinoma cell line MCF7: sensitive MCF7/WT, doxorubicin-selected MCF7/AdrR, and MDR1 -gene-transfected MCF7/BC19 cells with doxorubicin resistance factors of 1, 192, and 14, respectively. Accumulation of sestamibi and mean fluorescence of doxorubicin (5.5 μM) were assessed over 60 min in the presence and absence of Pgp modulators GG918 (0.01 to 0.2 μM) and PSC833 (0.05 to 2.0 μM). Accumulation curves for sestamibi and doxorubicin differed among the cell variants under control conditions, with sestamibi showing a significantly greater difference between WT and resistant cells than doxorubicin. Both GG918 and PSC833 reversed uptake deficits to WT levels for sestamibi in MCF7/BC19 cells and doxorubicin in MCF7/BC19 and MCF7/AdrR cells, but failed to show the same effect for sestamibi in MCF7/AdrR cells (∼30% of MCF7/WT level). Thus, both methods clearly distinguished sensitive from resistant MCF7 variants, with the radionuclide method showing greater sensitivity. © 2001 Cancer Research Campaign http://www.bjcancer.co

Modul Klasifikasi Aduan dengan Pendekatan Kemiripan Teks pada Aplikasi Perangkat Bergerak Suara Warga (SURGA) Kota Kediri

Kota Kediri yang memiliki sistem layanan pengaduan masyarakat yang bernama Suara Warga (SURGA) Kota Kediri. Dalam penerimaan aduan, terkadang aduan yang masuk ke dalam sistem memiliki kemiripan dengan aduan yang sudah ada. Hal ini dikarenakan adanya kemungkinan pengadu mengirimkan aduan berulang kali atau beberapa pengadu mengirimkan aduan dengan isi yang sama.Manhattan similarity adalah algoritma yang digunakan untuk mendeteksi kemiripan dua dokumen. Manhattan similarity dapat diimplementasikan pada aduan yang masuk ke dalam sistem. Aduan yang masuk diproses dengan pendekatan text similarity, yaitu text processing dan dimodelkan dalam bentuk vector space model sehingga dapat dihitung jarak antar aduan menggunakan Manhattan distance. Perhitungan jarak antar aduan dibatasi dengan penyusunan cluster menggunakan K-Means clustering, sehingga hanya aduan yang berada pada cluster atau klasifikasi yang sama yang dibandingkan. Setelah klasifikasi dan deteksi dilakukan, sejumlah aduan diambil dari setiap cluster dan ditanyakan kepada 15 responden. Hasil uji coba menunjukkan bahwa aduan dapat dideteksi kemiripannya dengan jarak Manhattan distance minimal 0,9993 antar aduan dengan tingkat akurasi untuk aduan tidak mirip 100% dan untuk aduan mirip 90%. Waktu total yang dibutuhkan untuk melakukan proses klasifikasi dan deteksi kemiripan teks adalah 17 menit 27 detik dengan jumlah aduan 387

Modul Klasifikasi Aduan dengan Pendekatan Kemiripan Teks pada Aplikasi Perangkat Bergerak Suara Warga (SURGA) Kota Kediri

Kota Kediri yang memiliki sistem layanan pengaduan masyarakat yang bernama Suara Warga (SURGA) Kota Kediri. Dalam penerimaan aduan, terkadang aduan yang masuk ke dalam sistem memiliki kemiripan dengan aduan yang sudah ada. Hal ini dikarenakan adanya kemungkinan pengadu mengirimkan aduan berulang kali atau beberapa pengadu mengirimkan aduan dengan isi yang sama.Manhattan similarity adalah algoritma yang digunakan untuk mendeteksi kemiripan dua dokumen. Manhattan similarity dapat diimplementasikan pada aduan yang masuk ke dalam sistem. Aduan yang masuk diproses dengan pendekatan text similarity, yaitu text processing dan dimodelkan dalam bentuk vector space model sehingga dapat dihitung jarak antar aduan menggunakan Manhattan distance. Perhitungan jarak antar aduan dibatasi dengan penyusunan cluster menggunakan K-Means clustering, sehingga hanya aduan yang berada pada cluster atau klasifikasi yang sama yang dibandingkan. Setelah klasifikasi dan deteksi dilakukan, sejumlah aduan diambil dari setiap cluster dan ditanyakan kepada 15 responden. Hasil uji coba menunjukkan bahwa aduan dapat dideteksi kemiripannya dengan jarak Manhattan distance minimal 0,9993 antar aduan dengan tingkat akurasi untuk aduan tidak mirip 100% dan untuk aduan mirip 90%. Waktu total yang dibutuhkan untuk melakukan proses klasifikasi dan deteksi kemiripan teks adalah 17 menit 27 detik dengan jumlah aduan 387

Extrinsic Fluorescent Dyes as Tools for Protein Characterization

Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are affected by the environment and by interactions of the dyes with proteins. In recent time, the use of extrinsic fluorescent dyes such as ANS, Bis-ANS, Nile Red, Thioflavin T and others has increased, because of their versatility, sensitivity and suitability for high-throughput screening. The intention of this review is to give an overview of available extrinsic dyes, explain their spectral properties, and show illustrative examples of their various applications in protein characterization

Risk factors for Coronavirus Disease 2019 (COVID-19) death in a population cohort study from the Western Cape Province, South Africa

BACKGROUND. Risk factors for coronavirus disease 2019 (COVID-19) death in sub-Saharan Africa and the effects of human immunodeficiency virus (HIV) and tuberculosis on COVID-19 outcomes are unknown. METHODS. We conducted a population cohort study using linked data from adults attending public-sector health facilities in the Western Cape, South Africa. We used Cox proportional hazards models, adjusted for age, sex, location, and comorbidities, to examine the associations between HIV, tuberculosis, and COVID-19 death from 1 March to 9 June 2020 among (1) public-sector “active patients” (≥1 visit in the 3 years before March 2020); (2) laboratory-diagnosed COVID-19 cases; and (3) hospitalized COVID-19 cases. We calculated the standardized mortality ratio (SMR) for COVID-19, comparing adults living with and without HIV using modeled population estimates. RESULTS. Among 3 460 932 patients (16% living with HIV), 22 308 were diagnosed with COVID-19, of whom 625 died. COVID- 19 death was associated with male sex, increasing age, diabetes, hypertension, and chronic kidney disease. HIV was associated with COVID-19 mortality (adjusted hazard ratio [aHR], 2.14; 95% confidence interval [CI], 1.70–2.70), with similar risks across strata of viral loads and immunosuppression. Current and previous diagnoses of tuberculosis were associated with COVID-19 death (aHR, 2.70 [95% CI, 1.81–4.04] and 1.51 [95% CI, 1.18–1.93], respectively). The SMR for COVID-19 death associated with HIV was 2.39 (95% CI, 1.96–2.86); population attributable fraction 8.5% (95% CI, 6.1–11.1). CONCLUSIONS. While our findings may overestimate HIV- and tuberculosis-associated COVID-19 mortality risks due to residual confounding, both living with HIV and having current tuberculosis were independently associated with increased COVID-19 mortality. The associations between age, sex, and other comorbidities and COVID-19 mortality were similar to those in other settings.The Western Cape Provincial Health Data Centre from the Western Cape Department of Health, the US National Institutes for Health (grant numbers R01 HD0804, the Bill and Melinda Gates Foundation, the United States Agency for International Development and the Wellcome Trust.https://academic.oup.com/cid/am2023Veterinary Tropical Disease

Antibody responses after first and second Covid-19 vaccination in patients with chronic lymphocytic leukaemia.

B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10-12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines