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Cabrini L, Silvani P, Landoni G, Monti G, Colombo S, Zangrillo A. Monitoring non-invasive ventilation outside the intensive care unit. Minerva Anestesiol 2010; 76:71-72. [PMID: 20125077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Angerami R, da Silva A, Nascimento E, Colombo S, Wada M, dos Santos F, Mancini D, de Oliveira R, Katz G, Martins E, da Silva L. Brazilian spotted fever: two faces of a same disease? A comparative study of clinical aspects between an old and a new endemic area in Brazil. Clin Microbiol Infect 2009; 15 Suppl 2:207-8. [DOI: 10.1111/j.1469-0691.2008.02160.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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do Nascimento EM, Colombo S, Nagasse-Sugahara T, Angerami R, Resende M, da Silva L, Katz G, dos Santos F. Evaluation of PCR-based assay in human serum samples for diagnosis of fatal cases of spotted fever group rickettsiosis. Clin Microbiol Infect 2009; 15 Suppl 2:232-4. [DOI: 10.1111/j.1469-0691.2008.02153.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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79
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Longo D, Colombo S, Dastrù W, Poggi L, Tedoldi F, Terreno E, Uggeri F, Aime S. CMR2009: 11.02: Evaluating iopamidol as pH-responsive CEST agent at 3 and 7 T. CONTRAST MEDIA & MOLECULAR IMAGING 2009. [DOI: 10.1002/cmmi.355] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zangrillo A, Colombo S, Salaris D, Cabrini L, Landoni G. Intensive care after elective non-cardiac surgery in high-risk patients. Minerva Anestesiol 2009; 75:537. [PMID: 19337187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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81
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Cabrini L, Monti G, Villa M, Pischedda A, Masini L, Dedola E, Whelan L, Marazzi M, Colombo S. Non-invasive ventilation outside the Intensive Care Unit for acute respiratory failure: the perspective of the general ward nurses. Minerva Anestesiol 2009; 75:427-433. [PMID: 19153554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND The introduction of non-invasive ventilation outside the Intensive Care Unit (ICU) is an increasing phenomenon, motivated by the shortage of intensive care beds and growing confidence with the technique. However, although general ward nurses are responsible for carrying out the daily management of the treatment and the extra monitoring it requires, their perspective on non-invasive ventilation (NIV) has never before been studied, and as a result their training is often neglected. METHODS A questionnaire was administered to the nurses of four non-intensive wards. The questionnaire addressed several issues, including the extent of the nurses' involvement in the decision to start the treatment, their relationship with the ward physicians and the Medical Emergency Team (MET), the monitoring, incidence, and management of errors and complications, the adhesion to the prescribed ventilatory program, and the desired training. RESULTS Out of 115 nurses, 90 completed the questionnaire (78.3%). Of this group, 67% did not feel involved in the decision-making process, and half felt they were inadequately informed. Approximately one third reported that they did not have adequate consultations with the doctors in the ward or with the MET. Only 13% of the nurses stated that the training was adequate (0% in medical wards). CONCLUSIONS Nurses indicated a strong demand for training on NIV, in order to improve their involvement with the therapeutic program and for better communication with the MET and ward doctors. We conclude that active research towards understanding their point of view should be included as part of the quality control of NIV treatments outside the ICU.
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Del Poggio P, Mattiello M, Gilardoni L, Jamoletti C, Colombo S, Zabbialini G. The mysterious case of spontaneous disappearance of hepatocellular carcinoma. Dig Liver Dis 2009; 41:e21-5. [PMID: 18420472 DOI: 10.1016/j.dld.2008.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 12/26/2007] [Accepted: 02/01/2008] [Indexed: 12/11/2022]
Abstract
We describe the case of a 77-year-old woman with chronic hepatitis C and well compensated cirrhosis in whom a single encapsulated 5.5 cm hepatocellular carcinoma was found in the right liver lobe. The patient was symptomatic with left upper quadrant pain and had elevated alfa-fetoprotein levels (3133 ng/ml). While she was waiting for liver resection and 2 months after the initial diagnosis the pain improved and alfa-fetoprotein levels normalized. A computerized tomography scan showed reduction in size of the lesion to 2.5 cm, with no central arterial enhancement, but with the demonstration of a peripheral rim enhancing in all dynamic phases. Follow up computerized tomography and magnetic resonance imaging examinations showed further reduction in size of the lesion to 1.3 cm with persistence of the enhancing rim 20 months after the initial diagnosis. The spontaneous and durable regression of the HCC and the persistent peripheral enhancing rim could be explained by a strong and persistent activation of the immune system directed against the neoplastic cells.
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Cabrini L, Monti G, Landoni G, Silvani P, Colombo S, Morero S, Mucci M, Bergonzi PC, Mamo D, Zangrillo A. Activities of a medical emergency team twenty years after its introduction. HSR PROCEEDINGS IN INTENSIVE CARE & CARDIOVASCULAR ANESTHESIA 2009; 1:28-33. [PMID: 23439387 PMCID: PMC3484559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
INTRODUCTION We describe and quantify the wide range of activities that a mature Medical Emergency Team can progressively perform. METHODS The activities performed by a Medical Emergency Team 20 years after its introduction were prospectively collected during 105 consecutive days. RESULTS The main activity was focused on the follow-up visits to previously treated critically ill patients (mean 7.5 visits/die in working days, 5.1 in the others). A large amount of other scheduled or unscheduled activities (like sedation or analgesia for diagnostic procedures, central venous line placement, phone consultation regarding critical care aspects of treatments) were performed: on average, 7.3 side-activities/die in working days and 5.2 in the others. First consultations in patients not previously seen were on average 3.1/die on working days, 2.4 in the others. Cardiac arrest accounted for 27 (9%) of first time visits. CONCLUSIONS A Medical Emergency Team can progressively perform many kinds of activities. An evaluation limited to the reduction of in-hospital cardiac arrests or a too early assessment may underestimate its beneficial effects on the Hospital complexity.
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Beccaria P, Cabrini L, Garancini MP, Colombo S. Recurarisation in a surgical ward. Anaesth Intensive Care 2008; 36:917. [PMID: 19115668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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85
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Cabrini L, Bergonzi PC, Mamo D, Dedola E, Colombo S, Morero S, Mucci M, Torri G. Dilatative percutaneous tracheostomy during double antiplatelet therapy: two consecutive cases. Minerva Anestesiol 2008; 74:565-567. [PMID: 18854797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This article reports two cases of dilatative percutaneous tracheostomy performed on patients treated with double antiplatelet therapy. Both patients had cardiac arrest following myocardial infarction. After primary angioplasty with stent placement, a double antiplatelet therapy was started. Due to poor neurological outcome, dilatative percutaneous tracheostomy was performed on both patients. Antiplatelet therapy was not discontinued because of the unacceptable risk of stent thrombosis. No immediate or late hemorrhagic complications occurred. In our experience, dilatative percutaneous tracheostomy during double antiplatelet therapy can be safely performed in selected patients without other risk factors.
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Toma S, Colombo S, Cornegliani L, Persico P, Galzerano M, Gianino MM, Noli C. Efficacy and tolerability of once-daily cephalexin in canine superficial pyoderma: an open controlled study. J Small Anim Pract 2008; 49:384-91. [PMID: 18631220 DOI: 10.1111/j.1748-5827.2008.00585.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The aims of this study were to evaluate the efficacy and tolerability of oral cephalexin given at 30 mg/kg once daily in dogs with superficial pyoderma and to compare them with those of oral cephalexin given at 15 mg/kg twice daily. METHODS Twenty dogs with superficial pyoderma were treated with cephalexin at 30 to 60 mg/kg orally once daily (group A) and compared with 20 dogs treated at a dose of 15 to 30 mg/kg orally twice daily (group B). Dogs were treated until 14 days after clinical remission. Type and distribution of lesions, pruritus and general health status were assessed every 14 days using a numerical scale until 14 days after treatment discontinuation. Total scores for each evaluation day were compared between the two groups as well as time to obtain resolution and percentage of relapses. RESULTS Resolution of superficial pyoderma was obtained in all dogs in 14 to 42 days (median 28 days for both groups), with no difference between groups. Six dogs experienced vomiting or diarrhoea but did not require discontinuation of the treatment. Only one dog (in group A) relapsed nine days after treatment discontinuation. CLINICAL SIGNIFICANCE Once-daily cephalexin is as effective as twice-daily cephalexin in the treatment of canine superficial pyoderma.
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Barreiro-Hurlé J, Colombo S, Cantos-Villar E. Is there a market for functional wines? Consumer preferences and willingness to pay for resveratrol-enriched red wine. Food Qual Prefer 2008. [DOI: 10.1016/j.foodqual.2007.11.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Monti G, Colombo S, Mininni M, Terzi V, Ortisi GM, Vesconi S, Casella G. Why measure endotoxin in septic shock patients? Crit Care 2008. [PMCID: PMC4088561 DOI: 10.1186/cc6411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Monti G, Terzi V, Mininni M, Colombo S, Vesconi S, Casella G. Polymyxin B hemoperfusion in high endotoxin activity level septic shock patients. Crit Care 2008. [PMCID: PMC4088829 DOI: 10.1186/cc6679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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90
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Moro M, Nizzero P, Biancardi A, Baldan R, Scarpellini P, Curti C, Cichero P, Ossi C, Mancini N, Colombo S, Marazzi M, Mazzuconi R, Cirillo D. An outbreak caused by multidrug-resistant OXA-58-positive Acinetobacter baumannii in an intensive care unit in Italy. J Hosp Infect 2008; 68:97-9. [DOI: 10.1016/j.jhin.2007.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Accepted: 10/12/2007] [Indexed: 12/22/2022]
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91
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Colombo S, Hill PB, Shaw DJ, Thoday KL. Requirement for additional treatment for dogs with atopic dermatitis undergoing allergen-specific immunotherapy. Vet Rec 2007; 160:861-4. [PMID: 17586789 DOI: 10.1136/vr.160.25.861] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Allergen-specific immunotherapy (ASIT) is one of the main treatments for atopic dermatitis in dogs, but it often requires additional treatments such as antibacterial and antifungal therapy for secondary bacterial and yeast infections, or antipruritic drugs to control the clinical signs or treat the adverse effects of the immunotherapy. Twenty-seven dogs enrolled in a study of ASIT were clinically assessed four times over a period of nine months; their requirement for treatment for secondary bacterial and yeast infections, for the administration of glucocorticoids as additional antipruritic therapy, and for the treatment of any adverse effects of the ASIT were evaluated. Twenty (74 per cent) of the dogs were treated for superficial bacterial pyoderma, 18 (66.6 per cent) required treatment for Malassezia species dermatitis on one or more occasions, eight (29.6 per cent) required treatment for otitis externa due to Malassezia species or bacteria, and eight required glucocorticoids to control their clinical signs. Five (18.5 per cent) of the dogs experienced adverse effects due to the ASIT and two required treatment with antihistamines (H1 receptor antagonists) in order to continue with the ASIT.
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Rotger M, Tegude H, Colombo S, Cavassini M, Furrer H, Décosterd L, Blievernicht J, Saussele T, Günthard HF, Schwab M, Eichelbaum M, Telenti A, Zanger UM. Predictive value of known and novel alleles of CYP2B6 for efavirenz plasma concentrations in HIV-infected individuals. Clin Pharmacol Ther 2007; 81:557-66. [PMID: 17235330 DOI: 10.1038/sj.clpt.6100072] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
To assess the association of CYP2B6 allelic diversity with efavirenz (EFV) pharmacokinetics, we performed extensive genotyping of 15 relevant single nucleotide polymorphism in 169 study participants, and full resequencing of CYP2B6 in individuals with abnormal EFV plasma levels. Seventy-seven (45.5%) individuals carried a known (CYP2B6*6, *11, *15, or *18) or new loss/diminished-function alleles. Resequencing defined two new loss-of-function alleles: allele *27 (marked by 593T>C [M198T]), that results in 85% decrease in enzyme activity and allele *28 (marked by 1132C>T), that results in protein truncation at arginine 378. Median AUC levels were 188.5 microg h/ml for individuals homozygous for a loss/diminished-function allele, 58.6 microg h/ml for carriers, and 43.7 microg h/ml for noncarriers (P<0.0001). Individuals with a poor metabolizer genotype had a likelihood ratio of 35 (95% CI, 11-110) of presenting very high EFV plasma levels. CYP2B6 poor metabolizer genotypes explain to a large extent EFV pharmacokinetics and identify individuals at risk of extremely elevated EFV plasma levels.
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Pareschi R, Colombo S, Mincione A, Righini S. The Modified Midfacial Degloving for Treatment of Large Juvenile Angiofibromas. Skull Base 2007. [DOI: 10.1055/s-2007-984086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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94
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Pareschi R, Colombo S, Mincione A. Surgery of Glomus Jugulare Tumors. Skull Base 2007. [DOI: 10.1055/s-2007-984239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Colombo S, Béguin A, Marzolini C, Telenti A, Biollaz J, Decosterd LA. Determination of the novel non-peptidic HIV-protease inhibitor tipranavir by HPLC–UV after solid-phase extraction. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 832:138-43. [PMID: 16359932 DOI: 10.1016/j.jchromb.2005.11.040] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Accepted: 11/21/2005] [Indexed: 10/25/2022]
Abstract
An HPLC method previously described for the assay of amprenavir (APV), ritonavir (RTV), indinavir (IDV), saquinavir (SQV), nelfinavir (NFV), lopinavir (LPV), atazanavir (ATV), nevirapine (NVP) and efavirenz (EFV) can be also conveniently applied, with minor gradient program adjustment, for the determination of the novel non-peptidic HIV protease inhibitor tipranavir (TPV) in human plasma, by off-line solid-phase extraction (SPE) followed by HPLC coupled with UV-diode array detection (DAD). After viral inactivation by heat, the plasma is diluted with phosphate buffer (pH 7), and subjected to a SPE on a C18 cartridge. Matrix components are eliminated with a solution of 0.1% H3PO4 solution neutralised to pH 7, and TPV is eluted with MeOH. The resulting eluate is evaporated and reconstituted in 100 microl MeOH/H2O 50/50. A 40 microl volume is injected onto a Nucleosil C18 AB column and TPV is analysed by UV detection at 201 nm using a gradient elution program constituted of MeCN and phosphate buffer adjusted to pH 5.12 and containing 0.02% sodium heptanesulfonate. The calibration curves are linear up to 75 microg/ml, with a lower limit of quantification of 0.125 microg/ml. The mean absolute recovery of TPV is 77.1+/-4.0%. The method is precise with mean inter-day coefficient of variations (CVs) within 2.2-3.4%, and accurate (range of inter-day deviations from 0.7 to 1.2%). The method has been validated and is currently applied to the monitoring of TPV plasma levels in HIV patients.
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Abstract
BACKGROUND Preliminary clinical and experimental results suggest that iron can modify hepatocytes' insulin sensitivity by interfering with insulin receptor and intracellular insulin signalling. AIM To evaluate in vivo the influence of iron on insulin resistance and insulin release in patients with non-alcoholic fatty liver disease and in vitro the interaction between iron and insulin sensitivity by analysing the effect of iron manipulation on insulin receptor expression in hepatoblastoma HepG2 cell line. RESULTS Insulin resistance evaluated by homeostatis model assessment (HOMA)-insulin resistance significantly decreased after diet, and a further reduction was observed after phlebotomies. Iron depletion by desferrioxamine increased by twofold the 125I-insulin-specific binding, whereas iron addition reduced insulin binding, similarly to cells exposed to high glucose concentration. CONCLUSION Iron status affects insulin sensitivity by modulating the transcription and membrane expression/affinity of insulin receptor expression in hepatocytes and influencing insulin-dependent gene expression suggesting that increased insulin clearance and decreased insulin resistance may contribute to the positive effect of iron depletion in patients with non-alcoholic fatty liver disease.
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Cantu G, Bimbi G, Squadrelli M, Riccio S, Colombo S, Poladas G, Compan A, Santamaria S, Gilardi R, Pompilio M, Rossi M. Adenocarcinoma of the Ethmoid Sinus: An Occupational Disease. Skull Base 2005. [DOI: 10.1055/s-2005-916462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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98
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Colombo S, Beguin A, Telenti A, Biollaz J, Buclin T, Rochat B, Decosterd LA. Intracellular measurements of anti-HIV drugs indinavir, amprenavir, saquinavir, ritonavir, nelfinavir, lopinavir, atazanavir, efavirenz and nevirapine in peripheral blood mononuclear cells by liquid chromatography coupled to tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 819:259-76. [PMID: 15833290 DOI: 10.1016/j.jchromb.2005.02.010] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Revised: 02/01/2005] [Accepted: 02/10/2005] [Indexed: 11/25/2022]
Abstract
A sensitive and accurate liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the intracellular determination of nine antiretroviral drugs in human peripheral blood mononuclear cells (PBMCs) is proposed. PBMCs are isolated by density gradient centrifugation using Vacutainer CPT tubes and cell count is performed with a Coulter instrument. Single-step extraction of drugs from PBMCs pellets is performed with MeOH 50% (with clozapine added as internal standard, I.S.) and the supernatant is injected onto a 2.1 mm x 30 mm SymmetryShield 3.5 microm-RP18 column equipped with a 2.1 x 10 mm guard column. Chromatographic separations are performed using a gradient program with a mixture of 2 mM ammonium acetate containing 0.1% formic acid and acetonitrile with 0.1% formic acid. Analytes quantification is performed by electro-spray ionisation-triple quadrupole mass spectrometry using the selected reaction monitoring (SRM) detection mode. The positive mode is used for the HIV protease inhibitors (PIs) indinavir, amprenavir, saquinavir, ritonavir, nelfinavir, lopinavir, atazanavir and the non-nucleoside reverse transcriptase inhibitors (NNRTIs) nevirapine, and the negative mode is applied for efavirenz. The calibration curves are prepared using blank PBMCs spiked with antiretroviral drugs at concentrations ranging from 0.5 to 100 ng/ml of cell extracts and fitted to a quadratic regression model weighted by 1/(concentration)(2). The lower limit of quantification is less than 0.5 ng/ml. The mean extraction recovery for all PIs/NNRTIs is always above 88%. The method is precise, with mean inter-day CV% within 0.6-10.2%, and accurate (range of inter-day deviation from nominal values -7.2 to +8.3%). This analytical method can be conveniently used in clinical research for the assessment of intracellular levels of all PIs/NNRTIs commercially available at present using a simple one-step cell extraction of PBMCs followed by liquid chromatography coupled with tandem triple quadripole mass detection.
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Colombo S, Guignard N, Marzolini C, Telenti A, Biollaz J, Decosterd LA. Determination of the new HIV-protease inhibitor atazanavir by liquid chromatography after solid-phase extraction. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 810:25-34. [PMID: 15358304 DOI: 10.1016/j.jchromb.2004.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Accepted: 07/09/2004] [Indexed: 11/26/2022]
Abstract
An HPLC method previously described for the simultaneous assay of amprenavir, ritonavir, indinavir, saquinavir, nelfinavir and efavirenz is proposed here for the simultaneous analysis of the new HIV protease inhibitor atazanavir (ATV) in human plasma, by off-line solid-phase extraction (SPE) followed by HPLC coupled with UV-diode array detection. After viral inactivation by heat (60 degrees C for 60 min), plasma (600 microl) with clozapine (internal standard) is diluted 1 + 1 with phosphate buffer pH 7 and subjected to a SPE on a C18 cartridge. Matrix components are eliminated with 2 x 500 microl of a solution of 0.1% H(3)PO(4) neutralised with NaOH to pH 7. ATV is eluted with 3 x 500 microl MeOH. The resulting eluate is evaporated under nitrogen at room temperature and is reconstituted in 100 microl MeOH/H(2)O 50/50. A 40 microl volume is injected onto a Nucleosil 100-5 microm C18 AB column. ATV is analysed by UV detection at 201 nm using a gradient elution program with solvents constituted of MeCN and phosphate buffer adjusted to pH 5.14. The mobile phase also contains 0.02% sodium heptanesulfonate, enabling an excellent separation of ATV from the other HIV protease inhibitors (PIs) amprenavir, indinavir, saquinavir, ritonavir, lopinavir, nelfinavir and the non-nucleoside reverse transcriptase inhibitors (NNRTIs) efavirenz and nevirapine. The calibration curves are linear up to 10 microg/ml, with a lower limit of quantification of 0.2 microg/ml. The mean absolute recovery of ATV is 96.4 +/- 3.2%. The method is precise with mean inter-day CVs within 1.1-6.1%, and accurate (range of inter-day deviations +0.3 to +2.3%). The method has been validated and is currently applied to the monitoring of ATV in HIV patients.
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Colombo S, Hill PB, Shaw DJ, Thoday KL. FC-55 Efficacy of low-dose immunotherapy in the treatment of canine atopic dermatitis: a prospective, double-blinded study. Vet Dermatol 2004. [DOI: 10.1111/j.1365-3164.2004.411_55.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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