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1.
Nature ; 595(7868): 600-605, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34262173

RESUMO

G-protein-coupled receptor (GPCR) kinases (GRKs) selectively phosphorylate activated GPCRs, thereby priming them for desensitization1. Although it is unclear how GRKs recognize these receptors2-4, a conserved region at the GRK N terminus is essential for this process5-8. Here we report a series of cryo-electron microscopy single-particle reconstructions of light-activated rhodopsin (Rho*) bound to rhodopsin kinase (GRK1), wherein the N terminus of GRK1 forms a helix that docks into the open cytoplasmic cleft of Rho*. The helix also packs against the GRK1 kinase domain and stabilizes it in an active configuration. The complex is further stabilized by electrostatic interactions between basic residues that are conserved in most GPCRs and acidic residues that are conserved in GRKs. We did not observe any density for the regulator of G-protein signalling homology domain of GRK1 or the C terminus of rhodopsin. Crosslinking with mass spectrometry analysis confirmed these results and revealed dynamic behaviour in receptor-bound GRK1 that would allow the phosphorylation of multiple sites in the receptor tail. We have identified GRK1 residues whose mutation augments kinase activity and crosslinking with Rho*, as well as residues that are involved in activation by acidic phospholipids. From these data, we present a general model for how a small family of protein kinases can recognize and be activated by hundreds of different GPCRs.


Assuntos
Receptor Quinase 1 Acoplada a Proteína G/química , Rodopsina/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Microscopia Crioeletrônica , Estrutura Terciária de Proteína , Transdução de Sinais
2.
Nat Chem Biol ; 19(5): 575-584, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604564

RESUMO

C-linked glycosylation is essential for the trafficking, folding and function of secretory and transmembrane proteins involved in cellular communication processes. The tryptophan C-mannosyltransferase (CMT) enzymes that install the modification attach a mannose to the first tryptophan of WxxW/C sequons in nascent polypeptide chains by an unknown mechanism. Here, we report cryogenic-electron microscopy structures of Caenorhabditis elegans CMT in four key states: apo, acceptor peptide-bound, donor-substrate analog-bound and as a trapped ternary complex with both peptide and a donor-substrate mimic bound. The structures indicate how the C-mannosylation sequon is recognized by this CMT and its paralogs, and how sequon binding triggers conformational activation of the donor substrate: a process relevant to all glycosyltransferase C superfamily enzymes. Our structural data further indicate that the CMTs adopt an unprecedented electrophilic aromatic substitution mechanism to enable the C-glycosylation of proteins. These results afford opportunities for understanding human disease and therapeutic targeting of specific CMT paralogs.


Assuntos
Manosiltransferases , Triptofano , Humanos , Manosiltransferases/genética , Manosiltransferases/química , Manosiltransferases/metabolismo , Triptofano/metabolismo , Glicosilação , Peptídeos/metabolismo , Proteínas de Membrana/metabolismo
3.
Nature ; 561(7724): E44, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29930353

RESUMO

In the PDF version of this Article, owing to a typesetting error, an incorrect figure was used for Extended Data Fig. 5; the correct figure was used in the HTML version. This has been corrected online.

4.
Nature ; 558(7711): 553-558, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29899450

RESUMO

G-protein-coupled receptors comprise the largest family of mammalian transmembrane receptors. They mediate numerous cellular pathways by coupling with downstream signalling transducers, including the hetrotrimeric G proteins Gs (stimulatory) and Gi (inhibitory) and several arrestin proteins. The structural mechanisms that define how G-protein-coupled receptors selectively couple to a specific type of G protein or arrestin remain unknown. Here, using cryo-electron microscopy, we show that the major interactions between activated rhodopsin and Gi are mediated by the C-terminal helix of the Gi α-subunit, which is wedged into the cytoplasmic cavity of the transmembrane helix bundle and directly contacts the amino terminus of helix 8 of rhodopsin. Structural comparisons of inactive, Gi-bound and arrestin-bound forms of rhodopsin with inactive and Gs-bound forms of the ß2-adrenergic receptor provide a foundation to understand the unique structural signatures that are associated with the recognition of Gs, Gi and arrestin by activated G-protein-coupled receptors.


Assuntos
Microscopia Crioeletrônica , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/ultraestrutura , Rodopsina/metabolismo , Rodopsina/ultraestrutura , Arrestina/química , Arrestina/metabolismo , Sítios de Ligação , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Humanos , Modelos Moleculares , Receptores Adrenérgicos beta 2/química , Receptores Adrenérgicos beta 2/metabolismo , Rodopsina/química , Transdução de Sinais , Especificidade por Substrato
5.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34782475

RESUMO

With conformation-specific nanobodies being used for a wide range of structural, biochemical, and cell biological applications, there is a demand for antigen-binding fragments (Fabs) that specifically and tightly bind these nanobodies without disturbing the nanobody-target protein interaction. Here, we describe the development of a synthetic Fab (termed NabFab) that binds the scaffold of an alpaca-derived nanobody with picomolar affinity. We demonstrate that upon complementary-determining region grafting onto this parent nanobody scaffold, nanobodies recognizing diverse target proteins and derived from llama or camel can cross-react with NabFab without loss of affinity. Using NabFab as a fiducial and size enhancer (50 kDa), we determined the high-resolution cryogenic electron microscopy (cryo-EM) structures of nanobody-bound VcNorM and ScaDMT, both small membrane proteins of ∼50 kDa. Using an additional anti-Fab nanobody further facilitated reliable initial three-dimensional structure determination from small cryo-EM test datasets. Given that NabFab is of synthetic origin, is humanized, and can be conveniently expressed in Escherichia coli in large amounts, it may be useful not only for structural biology but also for biomedical applications.


Assuntos
Microscopia Crioeletrônica/métodos , Fragmentos Fab das Imunoglobulinas/química , Proteínas de Membrana/química , Anticorpos de Domínio Único/química , Animais , Camelídeos Americanos , Camelus , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/imunologia , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Microscopia Eletrônica , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Alinhamento de Sequência , Análise de Sequência de Proteína
6.
Biochem Biophys Res Commun ; 672: 45-53, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37336124

RESUMO

Secretory proteins are used by pathogenic bacteria to manipulate the host systems and compete with other microorganisms, thereby enabling their survival in their host. Similar to other bacteria, secretory proteins of Mycobacterium tuberculosis also play a pivotal role in evading immune response within hosts, thereby leading to acute and latent tuberculosis infection. Prokaryotes have several classes of bacterial secretory systems out of which the Sec and Tat pathways are the most conserved in Mtb to transport proteins across the cytoplasmic membrane. Here, we report the crystal structure of a secretory protein, Rv0398c determined to 1.9 Å resolution. The protein comprises a core of antiparallel ß sheets surrounded by α helices adopting a unique ß sandwich fold. Structural comparison with other secretory proteins in Mtb and other pathogenic bacteria reveals that Rv0398c may be secreted via the Sec pathway. Our structural and in silico analyses thus provide mechanistic insights into the pathway adopted by Mtb to transport out secretory protein, Rv0398c which will facilitate the invasion to the host immune system.


Assuntos
Proteínas de Bactérias , Mycobacterium tuberculosis , Proteínas de Bactérias/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Mycobacterium tuberculosis/metabolismo , Proteínas de Transporte/metabolismo , Transporte Biológico
7.
Transfusion ; 63(9): 1747-1757, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37427683

RESUMO

BACKGROUND: Red Blood cells (RBCs) bring about harmful consequences during storage. MicroRNA (miRNA) dysregulation in stored RBCs could represent potential biomarkers of storage lesions. Although leukoreduction prevents damage to RBCs, it is uncertain whether leukoreduction of RBCs would impact the dysregulation of miRNAs during storage. This study evaluated the potential role of miRNAs for any alteration of leukoreduced (LR) and non-leukoreduced (NLR) RBCs till 21 days of storage. STUDY DESIGN AND METHODS: In this prospective study, thirty male volunteers' blood was equally divided into leukoreduced RBCs (LR) and NLR RBC (NLR) bags and stored till Day 21 at 4-60c. Selected miRNAs were quantified on Days 0 and 21. Further, bioinformatic tools were used to analyze the selected miRNAs and their predicted target genes (mRNAs) and identify the miRNA-mRNA regulatory relationships. RESULTS: A significantly higher fold change values of three miRNAs (miR-96-5p, miR-197-3p, miR-769-3p) were observed in NLR RBCs (p < .05). A significantly higher (p < .05) expression levels of miR-150-5p and miR-197-3p were observed in NLR RBCs till 21 days of storage. Further, the correlation with mRNA quantification confirmed the regulatory role of these miRNAs upon functional pathway enrichment analysis. DISCUSSION: A higher level of dysregulation of miRNAs was observed in NLR RBCs. Validation from In-Silico analysis suggested the regulatory role of miRNAs in cell apoptosis, senescence, and RBC-related signaling pathways. This indicated that stored LR RBCs would likely have better in vivo survival and function following transfusion. However, an in vivo study of miRNA in RBCs is warranted for conclusive evidence.


Assuntos
MicroRNAs , Humanos , Masculino , MicroRNAs/metabolismo , Preservação de Sangue , Estudos Prospectivos , Eritrócitos/metabolismo
8.
Vox Sang ; 118(1): 49-58, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36254849

RESUMO

BACKGROUND AND OBJECTIVES: Therapeutic plasma exchange (TPE) has been used in severe COVID-19 disease to eliminate the cytokine storm. This meta-analysis aims to assess the effectiveness of TPE in reducing mortality in severe COVID-19 disease compared to standard treatment. MATERIALS AND METHODS: A comprehensive literature search was performed in PubMed, the Cochrane database and the International Clinical Trial Registry Platform (ICTRP). The random-effect model was used to calculate the risk ratio and standardized mean difference (SMD) as pooled effect size for the difference in mortality and length of the intensive care unit (ICU) stay. The risk of bias and publication bias were assessed in R version 4.1.0. The certainty of the evidence was calculated using the GradePro tool. RESULTS: The database identified 382 participants from six studies, including one randomized control trial. Egger's test did not detect any publication bias (p = 0.178). The random model analysis for mortality evaluated a risk ratio of 0.38 (95% CI: 0.28-0.52) with a significant reduction in the TPE group. The certainty of the evidence was moderate, with a risk ratio of 0.34 (95% CI: 0.24-0.49). Length of ICU stays between TPE versus standard care showed an SMD of 0.08 (95% CI: -0.38, 0.55) and was not significant. CONCLUSION: The length of ICU stay in the TPE group was not different from standard care. However, this meta-analysis revealed a significant benefit of TPE in reducing mortality in severe COVID-19 disease compared to standard treatment.


Assuntos
COVID-19 , Humanos , COVID-19/terapia , Troca Plasmática
9.
Environ Res ; 221: 115263, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36640940

RESUMO

The present work entails the synthesis of thermally modified graphitic carbon nitride (GCN) using a two-step thermal treatment procedure and its subsequent use in the photocatalytic reduction of toxic pollutants such as rhodamine B dye (RhB) and chromium (VI) (Cr(VI)) from aquatic environments. The as-synthesised exfoliated GCN (GCNX) is characterised by X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller analysis (BET), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). These characterisations helped to elucidate the phase formation, chemical structure, composition, surface area, optical properties, and morphology of the sample. With assistance from a visible light source, GCNX can degrade RhB dye within 30 min in the presence of hydrogen peroxide (H2O2) and reduce Cr(VI) to Cr(III) in under 2 h in the presence of formic acid (FA/HCOOH). Variations in different catalytic parameters, including catalyst amount, pH of the solution, initial RhB or Cr(VI) concentration, and variation in H2O2 or FA concentration, are performed to inspect their effects on the photodegradation activity of GCNX. Moreover, the GCNX catalyst exhibits impressive stability and reusability. A thorough statistical evaluation follows the response surface methodology to understand the complex interaction between the factors contributing to the catalytic activity. The band alignment of differently functionalised GCN blocks in their pristine form and their H2O2/FA-adsorbed states is investigated using first-principles calculations to provide a further understanding of the RhB and Cr(VI) reduction mechanisms. The modified GCN can thus be effectively employed as a low-cost material for removing contamination from aquatic environments.


Assuntos
Poluentes Ambientais , Águas Residuárias , Peróxido de Hidrogênio
10.
Gastroenterology ; 161(2): 653-668.e16, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33915173

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is characterized by advanced disease stage at presentation, aggressive disease biology, and resistance to therapy, resulting in an extremely poor 5-year survival rate of <10%. PDAC is classified into transcriptional subtypes with distinct survival characteristics, although how these arise is not known. Epigenetic deregulation, rather than genetics, has been proposed to underpin progression, but exactly why is unclear and is hindered by the technical limitations of analyzing clinical samples. METHODS: We performed genome-wide epigenetic mapping of DNA modifications 5-methylcytosine and 5-hydroxymethylcytosine (5hmc) using oxidative bisulfite sequencing from formalin-embedded sections. We identified overlap with transcriptional signatures in formalin-fixed, paraffin-embedded tissue from resected patients, via bioinformatics using iCluster and mutational profiling and confirmed them in vivo. RESULTS: We found that aggressive squamous-like PDAC subtypes result from epigenetic inactivation of loci, including GATA6, which promote differentiated classical pancreatic subtypes. We showed that squamous-like PDAC transcriptional subtypes are associated with greater loss of 5hmc due to reduced expression of the 5-methylcytosine hydroxylase TET2. Furthermore, we found that SMAD4 directly supports TET2 levels in classical pancreatic tumors, and loss of SMAD4 expression was associated with reduced 5hmc, GATA6, and squamous-like tumors. Importantly, enhancing TET2 stability using metformin and vitamin C/ascorbic acid restores 5hmc and GATA6 levels, reverting squamous-like tumor phenotypes and WNT-dependence in vitro and in vivo. CONCLUSIONS: We identified epigenetic deregulation of pancreatic differentiation as an underpinning event behind the emergence of transcriptomic subtypes in PDAC. Our data showed that restoring epigenetic control increases biomarkers of classical pancreatic tumors that are associated with improved therapeutic responses and survival.


Assuntos
5-Metilcitosina/análogos & derivados , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/metabolismo , Epigênese Genética , Fator de Transcrição GATA6/genética , Neoplasias Pancreáticas/genética , Transcrição Gênica , 5-Metilcitosina/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Ascórbico/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/enzimologia , Carcinoma Ductal Pancreático/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Epigênese Genética/efeitos dos fármacos , Epigenoma , Epigenômica , Fator de Transcrição GATA6/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metformina/farmacologia , Camundongos Nus , Camundongos Transgênicos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Proteína Smad4/genética , Proteína Smad4/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcriptoma , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Vox Sang ; 117(8): 989-1000, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35645211

RESUMO

BACKGROUND AND OBJECTIVES: Exchange transfusion is a valuable treatment option in sickle cell disease (SCD) and is preferred over simple transfusion as it removes abnormal haemoglobin S (HbS) levels and reduces complications. This meta-analysis aims to evaluate the efficacy and safety profile of automated red cell exchange (aRBX) procedure over manual red cell exchange transfusion (MET) in SCD patients. MATERIALS AND METHODS: A standard meta-analysis protocol was developed, and after performing a comprehensive literature search in PubMed/MEDLINE, Cochrane and International Clinical Trial Registry Platform (ICTRP), reviewers assessed eligibility and extracted data from nine relevant studies. A random effects model was used to estimate the pooled effect size calculated from the mean difference in HbS percentage, serum ferritin level and risk ratio for the adverse events. Quality assessment was done using the risk-of-bias assessment tool, and a summary of observations was prepared using standard Cochrane methodology with GradePro GDT. RESULTS: The random-model analysis revealed a mean difference of 4.10 (95% CI: -3.29-11.49; Z = 1.09; p = 0.28) for HbS percentage, mean difference of 435.29 (95% CI: -73.74-944.32; Z = 1.68; p = 0.09) for serum ferritin and pooled risk ratio of 1.35 (95% CI: 0.63-2.87; Z = 0.77; p = 0.44) for adverse events. CONCLUSION: This meta-analysis did not reveal any significant benefit of aRBX in reducing HbS percentage and attenuating the serum ferritin level when compared with MET. There was also no significant increased risk of adverse events detected in association with aRBX.


Assuntos
Anemia Falciforme , Transfusão de Eritrócitos , Anemia Falciforme/terapia , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/métodos , Eritrócitos , Ferritinas , Humanos
12.
Vox Sang ; 117(5): 656-663, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35114023

RESUMO

BACKGROUND AND OBJECTIVES: Blood donor deferral is an essential tool for blood safety. The ongoing COVID-19 pandemic has adversely affected blood transfusion services all over the world. But its impact on donor deferral rate and the pattern is unclear in light of the new donor deferral policy due to the COVID-19 pandemic. MATERIALS AND METHODS: This retrospective study was divided into pre-COVID and COVID (15 March 2019-14 March 2021). All the deferred donors were divided into six different categories: (1) medical causes, (2) surgical causes, (3) drugs and vaccination, (4) risk of transfusion-transmitted diseases, (5) miscellaneous causes and (6) flu-like symptoms. In addition, COVID-related deferrals were also incorporated. All these above categories along with the donor demography were analysed by SPSS software version 25. RESULTS: The donor deferral rate was 17.03% and 12.74% during the pre-COVID and COVID periods, respectively. During the pre-COVID period, Category 3 deferrals and during COVID period, Category 6 deferrals were significantly higher. A reversal in pattern with increased blood pressure (40.2% vs. 24.04%) over-riding low haemoglobin (34.77% vs. 55.5%) was noted in the Category 1 deferral during the COVID period. Category 1 deferral was more in middle-aged adults as compared to young and old adults (p < 0.05). Among middle-aged adults, deferral due to flu-like symptoms was also significantly more during the COVID period (p < 0.05). CONCLUSION: COVID-19 significantly affected the donor pool and changed the pattern of donor deferral. Understanding donor deferral patterns may help in identifying targeted donor populations and planning donor recruitment strategies in future pandemic crises.


Assuntos
Doadores de Sangue , COVID-19 , Adulto , Segurança do Sangue , COVID-19/epidemiologia , Seleção do Doador , Humanos , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos
13.
J Clin Apher ; 37(3): 273-280, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35119768

RESUMO

BACKGROUND: The COVID-19 convalescent plasma (CCP) has been tried as a therapy in moderate COVID-19 pneumonia. Donation of CCP requires motivation from recovered patients. This study evaluated the response of such recovered health care workers (HCWs) when they were motivated for CCP donation. METHODS: An interview-based survey was carried out with recovered HCWs as study participants between August 2020 and November 2020. A qualified social worker explained the details of CCP donation over a mobile call; he clarified all their doubts and motivated them for the plasma donation. Their responses were recorded as "interested" or "not interested" followed by analysis. RESULTS: We tried to call 624 recovered HCWs, but could not reach 213, and the final group available for the study was 411 participants. Of these 411, 186 were deferred. Finally, we analyzed a total of 225 responses. Eventually, 105 out of 225 HCWs (47%) were interested; there were no significant differences in responses among males and females and between different age groups (<.001) and the "doctors" designation category (P = .01) had a maximum number of "interested" responses. In multivariate logistic regression, only the "interested" responses of the doctors were significantly higher after adjusting the confounding effect of the "graduate and above" educational qualification category. CONCLUSION: This study found that nearly half of the eligible HCWs were interested in CCP donation. The educational qualification and designation among the recovered HCWs had an impact on CCP donation interest. The doctors were more interested in CCP donation compared to others.


Assuntos
Remoção de Componentes Sanguíneos , COVID-19 , COVID-19/terapia , Feminino , Pessoal de Saúde , Humanos , Imunização Passiva , Masculino , SARS-CoV-2 , Soroterapia para COVID-19
14.
Angew Chem Int Ed Engl ; 61(20): e202200163, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35194928

RESUMO

Herein, we describe the development and application of a novel expressed protein selenoester ligation (EPSL) methodology for the one-pot semi-synthesis of modified proteins. EPSL harnesses the rapid kinetics of ligation reactions between modified synthetic selenopeptides and protein aryl selenoesters (generated from expressed intein fusion precursors) followed by in situ chemoselective deselenization to afford target proteins at concentrations that preclude the use of traditional ligation methods. The utility of the EPSL technology is showcased through the efficient semi-synthesis of ubiquitinated polypeptides, lipidated analogues of the membrane-associated GTPase YPT6, and site-specifically phosphorylated variants of the oligomeric chaperone protein Hsp27 at high dilution.


Assuntos
Peptídeos , Proteínas
15.
Br J Cancer ; 124(3): 581-586, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33100327

RESUMO

BACKGROUND: The Phase 2 SCALOP trial compared gemcitabine with capecitabine-based consolidation chemoradiotherapy (CRT) in locally advanced pancreatic cancer (LAPC). METHODS: Thirty-five systematically identified circulating biomarkers were analysed in plasma samples from 60 patients enroled in SCALOP. Each was measured in triplicate at baseline (prior to three cycles of gemcitabine-capecitabine induction chemotherapy) and, for a subset, prior to CRT. Association with overall survival (OS) was determined using univariable Cox regression and optimal thresholds delineating low to high values identified using time-dependent ROC curves. Independence from known prognostic factors was assessed using Spearman correlation and the Wilcoxon rank sum test prior to multivariable Cox regression modelling including independent biomarkers and known prognostic factors. RESULTS: Baseline circulating levels of C-C motif chemokine ligand 5 (CCL5) were significantly associated with OS, independent of other clinicopathological characteristics. Patients with low circulating CCL5 (CCL5low) had a median OS of 18.5 (95% CI 11.76-21.32) months compared to 11.3 (95% CI 9.86-15.51) months in CCL5high; hazard ratio 1.95 (95% CI 1.04-8.65; p = 0.037). CONCLUSIONS: CCL5 is an independent prognostic biomarker in LAPC. Given the known role of CCL5 in tumour invasion, metastasis and the induction of an immunosuppressive micro-environment, targeting of CCL5-mediated pathways may offer therapeutic potential in pancreatic cancer. CLINICAL TRIAL REGISTRATION: The SCALOP trial was registered with ISRCTN, number 96169987 (registered 29 May 2008).


Assuntos
Biomarcadores Tumorais/sangue , Capecitabina/uso terapêutico , Quimiocina CCL5/sangue , Quimiorradioterapia/métodos , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/terapia , Idoso , Citocinas/sangue , Desoxicitidina/uso terapêutico , Feminino , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Curva ROC , Análise de Regressão , Resultado do Tratamento , Gencitabina
16.
Transfus Apher Sci ; 60(1): 103066, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33472742

RESUMO

Cell processing laboratories are an important part of cancer treatment centers. Cell processing laboratories began by supporting hematopoietic stem cell (HSC) transplantation programs. These laboratories adapted closed bag systems, centrifuges, sterile connecting devices and other equipment used in transfusion services/blood banks to remove red blood cells and plasma from marrow and peripheral blood stem cells products. The success of cellular cancer immunotherapies such as Chimeric Antigen Receptor (CAR) T-cells has increased the importance of cell processing laboratories. Since many of the diseases successfully treated by CAR T-cell therapy are also treated by HSC transplantation and since HSC transplantation teams are well suited to manage patients treated with CAR T-cells, many cell processing laboratories have begun to produce CAR T-cells. The methods that have been used to process HSCs have been modified for T-cell enrichment, culture, stimulation, transduction and expansion for CAR T-cell production. While processing laboratories are well suited to manufacture CAR T-cells and other cellular therapies, producing these therapies is challenging. The manufacture of cellular therapies requires specialized facilities which are costly to build and maintain. The supplies and reagents, especially vectors, can also be expensive. Finally, highly skilled staff are required. The use of automated equipment for cell production may reduce labor requirements and the cost of facilities. The steps used to produce CAR T-cells are reviewed, as well as various strategies for establishing a laboratory to manufacture these cells.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Laboratórios/normas , Receptores de Antígenos Quiméricos/imunologia , Condicionamento Pré-Transplante/métodos , Humanos
17.
Transfus Apher Sci ; 60(1): 103013, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33272849

RESUMO

INTRODUCTION: Polyagglutination is a rare entity in immunohematology and unusually presents in a healthy blood donor. The general presentation was described in the literature in association with bacterial infections, which result in the exposure of crypt antigens. Nowadays, polyagglutination is rarely detected due to the use of monoclonal antisera. Our case report describes the presence of Tn polyagglutination in a healthy adult blood donor with no prior history of any infection in the recent past. METHODS: Immunohematology work-up for incompatible cross-match was done in the serology lab using commercially procured antisera and column agglutination gel card (Tulip Diagnostics India Pvt. Ltd, Goa, India). The three cell-screening panel was procured commercially (ID Dia cell I, II, III; Bio-Rad, Switzerland), and in-house lectin was prepared as per the standard method. RESULT: We have come across a case of incompatible cross-match with negative antibody screen, auto-control, and Negative direct coombs test. Cross-match with multiple adult serum and cord serum gives us a clue towards polyagglutination. Further, Polyagglutination was confirmed serologically using anti-A1 lectin and later concludes of Tn type by lectin prepared in-house from Salvia Sclarea. CONCLUSION: Resolution of incompatible cross-match in a case of polyagglutination needs a skilled workforce and rare reagents. Identification of reason for incompatibility helps in an early issue of blood units.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Eritrócitos/metabolismo , Adulto , Doenças Autoimunes , Voluntários Saudáveis , Humanos , Masculino
18.
Water Sci Technol ; 84(7): 1804-1812, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34662314

RESUMO

Discharge of oily wastewater imparts serious threat to the environment because of high level concentration of chemical oxygen demand (COD), biochemical oxygen demand (BOD) as well as oil and grease and it is difficult to treat such wastewater due to its inherent toxic and inhibitory property. A treatability study of oily wastewater (carrying petroleum) has been performed in the present work using a batch suspended growth reactor. The experiment was conducted using acclimatized suspended biomass in laboratory environment and the kinetic coefficients were determined which are immensely important for the design of such reactor. The oil removal efficiency was observed to be in the range of 62.84-85.45% corresponding to average MLSS concentration range of 1,797-3,668 mg/L. Haldane kinetic model was found to be the best fitted for the biodegradation of oily wastewater with acclimatised microorganisms in the present investigation. The kinetic co-efficients including Ks, Y, kd, k and ki were calculated from the experimental data and the values were compared with published results cited by various scientists. The derived kinetic coefficients values are to be useful for understanding the dynamics of substrate utilisation with production of biomass and efficient design of biological systems and also for pilot plant investigation with real life wastewater of similar nature.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Cinética
19.
Artigo em Inglês | MEDLINE | ID: mdl-33573477

RESUMO

One of the complex environmental problems that triggers at present is oily wastewater contamination arising out of the activities related to engineering vehicular (automobile) workshop or garage, kitchens in houses and restaurants, gas stations, metal finishing house, petrochemical industry, edible oil production unit etc. Oily wastewater discharge is a major issue of environmental pollution in the present decade as some of its constituents are hazardous in nature. Hence, appropriate treatment technology for oily wastewater needs to be addressed. Biological treatment (BT) technique would be the best option in this regard, because it has multiple advantages over various other techniques as available today. BT degrades effectively the harmful constituents of oily wastewater into innocuous products that are environment friendly and it is considered to be the economical method. The resulting effluent of pretreatment followed by biological treatment of oily wastewater can be reused after conforming discharge limits. Again, numerous research works in these days have optimized the function and result of existing laboratory and pilot scale treatment technologies. This review paper describes a comprehensive understanding of the origin and characteristics, existing techniques in laboratory and pilot scale, screening of different methods, justification for advocating biological methods for treatment of oily wastewater.


Assuntos
Óleos/isolamento & purificação , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água , Biodegradação Ambiental , Óleos Combustíveis , Hidrocarbonetos/isolamento & purificação
20.
Br J Cancer ; 123(5): 709-713, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32641867

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic epicentre has moved to the USA and Europe, where it is placing unprecedented demands on healthcare resources and staff availability. These service constraints, coupled with concerns relating to an increased incidence and severity of COVID-19 among patients with cancer, should lead to re-consideration of the risk-benefit balance for standard treatment pathways. This is of particular importance to pancreatic cancer, given that standard diagnostic modalities such as endoscopy may be restricted, and that disease biology precludes significant delays in treatment. In light of this, we sought consensus from UK clinicians with an interest in pancreatic cancer for management approaches that would minimise patient risk and accommodate for healthcare service restrictions. The outcomes are described here and include recommendations for treatment prioritisation, strategies to bridge to later surgical resection in resectable disease and factors that modify the risk-benefit balance for treatment in the resectable through to the metastatic settings. Priority is given to strategies that limit hospital visits, including through the use of hypofractionated precision radiotherapy and chemoradiotherapy treatment approaches.


Assuntos
Betacoronavirus , Consenso , Infecções por Coronavirus/epidemiologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Pneumonia Viral/epidemiologia , Guias de Prática Clínica como Assunto , COVID-19 , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Humanos , Incidência , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Quarentena/métodos , Risco , SARS-CoV-2 , Reino Unido/epidemiologia
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