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Weber R, Christen L, Christen S, Tschopp S, Znoj H, Schneider C, Schmitt J, Opravil M, Günthard HF, Ledergerber B, Battegay M, Bernasconi E, Bucher H, Bürgisser P, Egger M, Erb P, Fierz W, Fischer M, Flepp M, Francioli P, Furrer HJ, Gorgievski M, Günthard H, Grob P, Hirschel B, Kaiser L, Kind C, Klimkait T, Ledergerber B, Lauper U, Opravil M, Paccaud F, Pantaleo G, Perrin L, Piffaretti JC, Rickenbach M, Rudin C, Schupbach J, Speck R, Telenti A, Trkola A, Vernazza P, Wagels T, Weber R, Yerly S. Effect of Individual Cognitive Behaviour Intervention on Adherence to Antiretroviral Therapy: Prospective Randomized Trial. Antivir Ther 2004. [DOI: 10.1177/135965350400900111] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objective A high level of adherence to antiretroviral therapy is required for complete suppression of HIV replication, immunological and clinical effectiveness. We investigated whether cognitive behaviour therapy can improve medication adherence. Design Prospective randomized 1-year trial. Setting Collaboration of HIV university outpatient clinic and psychotherapists in private practice. Participants 60 HIV-infected persons on stable anti-retroviral combination therapy and viral load below 50 copies/ml. Intervention Cognitive behaviour intervention in individual patients, in addition to standard of care. Main outcome measures Feasibility and acceptance of intervention; adherence to therapy assessed using medication event monitoring system (MEMS) and self-report questionnaire; virological failure; psychosocial measures. Results The median number of sessions for cognitive behaviour intervention per patient during the 1-year trial was 11 (range 2–25). At months 10–12, mean adherence to therapy as assessed using MEMS was 92.8% in the intervention and 88.9% in the control group ( P=0.2); the proportion of patients with adherence ≥95% was 70 and 50.0% ( P=0.014), respectively. While there was no significant deterioration of adherence during the study in the intervention arm, adherence decreased by 8.7% per year ( P=0.006) in the control arm. No differences between the intervention group and standard of care group were found regarding virological outcome. Compared with the control group, participants in the intervention group perceived a significant improvement of their mental health during the study period. Conclusions Cognitive behavioural support in addition to standard of care of HIV-infected persons is feasible in routine practice, and can improve medication adherence and mental health.
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Perrin L, Maron L, Eisenstein O. Modelling Me5C5for reactivity studies in (η5-C5Me5)2Ln–R: full DFT and QM/MM approaches. NEW J CHEM 2004. [DOI: 10.1039/b404478a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Perrin L, Maron L, Eisenstein O, Schwartz DJ, Burns CJ, Andersen RA. Bonding of H2, N2, Ethylene, and Acetylene to Bivalent Lanthanide Metallocenes: Trends from DFT Calculations on Cp2M and Cp*2 M (M = Sm, Eu, Yb) and Experiments with Cp*2Yb. Organometallics 2003. [DOI: 10.1021/om034206v] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ananworanich J, Nuesch R, Le Braz M, Chetchotisakd P, Vibhagool A, Wicharuk S, Ruxrungtham K, Furrer H, Cooper D, Hirschel B, Bernasconi E, Cavassini M, Ebnöther C, Fagard C, Genné D, Khanna N, Perrin L, Phanupak P, Ubolyam S, Vernazza P, Yerly S. Failures of 1 week on, 1 week off antiretroviral therapies in a randomized trial. AIDS 2003; 17:F33-7. [PMID: 14523294 DOI: 10.1097/00002030-200310170-00001] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Scheduled treatment interruptions are being evaluated in an effort to decrease costs and side effects of highly active antiretroviral therapy (HAART). A schedule of 1 week on and 1 week off therapy offers the promise of 50% less drug exposure with continuously undetectable HIV RNA concentration. METHODS In the Staccato study 600 patients on successful HAART were to be randomized to either continued therapy, CD4-guided therapy, or one week on, one week off therapy. A scheduled preliminary analysis evaluated effectiveness in the 1-week-on-1-week-off arm. RESULTS Of 36 evaluable patients, 19 (53%) had two successive HIV RNA concentrations > 500 copies/ml at the end of the week off therapy, and were classified as virological failure. Most of those who failed took didanosine, stavudine, saquinavir, and ritonavir (11 patients). In these patients, there was no evidence of mutations suggestive of drug resistance, and plasma saquinavir levels were within the expected range. Two of three patients failing on triple nucleotides had drug resistance mutations, but nonetheless responded to reintroduction of triple nucleotide therapy. One of two patients taking nevirapine, and one of eight taking efavirenz, also failed. Both had resistance mutations at the time of failure, but not at baseline. CONCLUSIONS The 1-week-on-1-week-off schedule, as tested in the Staccato study, showed an unacceptably high failure rate and was therefore terminated.
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El Brihi T, Jaubert JN, Barth D, Perrin L. VOCs isotherms on day zeolite by static and dynamic methods: experiments and modelling. ENVIRONMENTAL TECHNOLOGY 2003; 24:1201-1210. [PMID: 14669800 DOI: 10.1080/09593330309385662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A dynamic method and a static gravimetric method are respectively used to measure the adsorption equilibria of m-xylene and n-butyl acetate on Wessalith DAY zeolite F20. The equilibrium experiments are performed at different temperatures for both volatile organic compounds (VOCs). The m-xylene isotherms obtained in this study by the dynamic method are compared to our recently published data in which the static gravimetric method was used in order to test the influence of the experimental technique. Because the adsorption isotherms of m-xylene were correlated in our previous paper, in this study only the n-butyl acetate experimental data are correlated with various adsorption isotherm models: Langmuir, Toth and Dubinin equations.
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Eisenstein O, Hitchcock PB, Khvostov AV, Lappert MF, Maron L, Perrin L, Protchenko AV. Mono-, di-, and Ttianionic beta-diketiminato ligands: a computational study and the synthesis and structure of [(YbL)(3)(THF)], L = [[N(SiMe(3))C(Ph)](2)CH]. J Am Chem Soc 2003; 125:10790-1. [PMID: 12952450 DOI: 10.1021/ja036902s] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A trinuclear Yb beta-diketiminato cluster [(YbL)3(THF)] (1) (L = {N(SiMe3)C(Ph)}2CH), containing L-1 and L-3 as well as Yb(II) and Yb(III) centers, was obtained by treatment of [YbL2] with Yb-naphthalene and was characterized by X-ray crystallography. The electron distribution in 1 and the Yb(II)/L-2 complex [Yb{(mu-L)Li(THF)}2] (2) was analyzed by DFT and ONIOM (QM/MM) calculations.
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Kaiser L, Deffernez C, Thomas Y, Koch D, Spicher VM, Uckay I, Schultze D, Siegl G, Perrin L, Matter HC, Wunderli W. Viral aetiology of acute respiratory illnesses in patients with a suspicion of severe acute respiratory syndrome (SARS) in Switzerland. Swiss Med Wkly 2003; 133:400-1. [PMID: 12947530 DOI: 10.4414/smw.2003.10394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Kaiser L, Deffernez C, Thomas Y, Koch D, Spicher VM, Uckay I, Schultze D, Siegl G, Perrin L, Matter HC, Wunderli W. Viral aetiology of acute respiratory illnesses in patients with a suspicion of severe acute respiratory syndrome (SARS) in Switzerland. Swiss Med Wkly 2003; 133:400-1. [PMID: 12947530 DOI: 2003/27/smw-10394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Haupts S, Ledergerber B, Böni J, Schüpbach J, Kronenberg A, Opravil M, Flepp M, Speck RF, Grube C, Rentsch K, Weber R, Günthard HF, Bachmann S, Battegay M, Bernasconi E, Bucher H, Bürgisser P, Egger M, Erb P, Fierz W, Fischer M, Flepp M, Francioli P, Furrer HJ, Gorgievski M, Günthard H, Grob P, Hirschel B, Kaiser L, Kind C, Klimkait T, Ledergerber B, Lauper U, Opravil M, Paccaud F, Pantaleo G, Perrin L, Piffaretti JC, Rickenbach M, Rudin C, Schupbach J, Speck R, Telenti A, Trkola A, Vernazza P, Weber R, Yerly S. Impact of Genotypic Resistance Testing on Selection of Salvage Regimen in Clinical Practice. Antivir Ther 2003. [DOI: 10.1177/135965350300800512] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective To determine whether genotypic resistance testing leads to selection of more potent drug regimens when compared to regimens based on treatment history only. Design Prospective, tertiary care centre-based study. Patients: One-hundred-and-forty-five HIV-infected adults on stable antiretroviral therapy (ART) for >6 months experiencing virological failure. Methods The physicians’ decision-making process when choosing a salvage regimen was prospectively documented: at time of virological failure, on ‘failing ART’, genotyping was performed and a hypothetical ‘clinical expert ART’ based upon patient's drug history was documented. Subsequently, data on resistance mutations, rating by a decision support software and drug history were used to define ‘genotyping ART’. After discussion with the patient, final treatment, ‘new personalized ART’ was chosen and prescribed. To compare the relative potency of the four ART regimens in a standardized manner, a resistance score ranging from 1 (best) to 8 (worst) based on drug ranking by decision support software was attributed to each ART regimen. Virological and immunological outcomes were analysed based on the magnitude of the resistance score. Results Median follow-up was 1.5 years. In all 145 patients, median resistance scores for the stepwise selected ART regimens were: ‘failing ART’: 4.5, ‘clinical expert ART’: 1.8, ‘genotyping ART’: 1.5 and ‘new personalized ART’: 2. The latter was 1.5 in patients who effectively switched to ‘new personalized ART’ ( n=89). Lower resistance scores translated into significantly improved virological response after initiation of ‘new personalized ART’. In multivariable analysis, lower resistance scores, lower baseline HIV RNA levels and use of novel antiretroviral drugs were associated with the probability of reducing plasma viraemia to <50 copies/ml. Conclusions: This study suggests that treatment choices including genotype and decision support software were virologically superior to those based on drug history only.
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Bourdin A, Kierzek G, Parera K, Perrin L, Tixier F, Paganin F. [Chylothorax: an unexpected complication of artificial ventilation in severe acute asthma]. Rev Mal Respir 2003; 20:279-82. [PMID: 12844026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
INTRODUCTION Complications of mechanical ventilation for severe acute asthma are common and are related essentially to barotrauma. However, the incidence has declined in recent years thanks to different techniques of ventilation. CASE REPORT We report a case of spontaneous chylothorax occurring during the course of ventilation in a patient with severe acute asthma where the ventilatory parameters were in accordance with current recommendations. Recovery was straightforward with resolution of the chylothorax and no recurrence either immediately or later. Exhaustive clinical, biological and morphological investigations failed to find any cause other than the mechanical ventilation. CONCLUSION This case of chylothorax may be considered as a rare barotraumatic complication of severe acute asthma.
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Perrin L, Maron L, Eisenstein O. Some structural and electronic properties of MX3(M = Ln, Sc, Y, Ti+, Zr+, Hf+; X = H, Me, Hal, NH2) from DFT calculations. Faraday Discuss 2003; 124:25-39; discussion 53-6, 453-5. [PMID: 14527207 DOI: 10.1039/b212276f] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The geometry of trivalent homoleptic d0 MX3 (X = H, Me, Hal, NH2) complexes for the entire lanthanide family, neutral group 3 and cationic group 4 metal center complexes have been studied with DFT(B3PW91) calculations. The geometrical parameters are in good agreement with the available experimental data. The degree of pyramidalization of the metal is discussed. The hydride and alkyl complexes are strongly pyramidal. In the case of the halide, a pyramidal structure is preferred for fluoride and the systems become increasingly planar with heavier halides. The geometrical trends with X are similar for group 3, group 4 and lanthanide complexes. However group 3 complexes are almost planar, group 4 strongly pyramidal and lanthanide intermediate. The lanthanide contraction is reproduced. A natural bond orbital (NBO) charge analysis is used to rationalize the results. This highlights the similarities and differences in the M-X bonding in the three families of complexes. In all cases, the pyramidalization is related to the participation of the valence d orbitals in the M-X bonds but the M-X bond is mostly ionic in lanthanide and considerably more covalent for the d transition metals. The hydride and alkyl complexes, which have more covalent character than the halide complexes are more pyramidal. In the case of the halide complexes, the fluoride complexes, in which there is the least population of the M d orbitals, are found to be more pyramidal because the increasing covalency with heavier halide stabilizes the planar structure through dpi-ppi interaction. The electronic metal d-p transition of the free ion is shown to be a good indicator of the pyramidalization at M although these values should only be used qualitatively. The strong ionic character of the Ln-X bond gives a rationale for the more important elongation of the beta Si-C bond in La(CH(SiMe3)2)3 than in La(N(SiMe3)2)3. The elongation is shown to be in part due to the negative hyperconjugation of the lone pair used for the Ln-ligand bonds in the beta bonds.
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Perrin L, Maron L, Eisenstein O, Lappert MF. γ Agostic C–H or β agostic Si–C bonds in La{CH(SiMe3)2}3? A DFT study of the role of the ligand. NEW J CHEM 2002. [DOI: 10.1039/b206120c] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
A theoretical study of SiH(4) activation by Cp(2)LnH complexes for the entire series of lanthanides has been carried out at the DFT-B3PW91 level of theory. The reaction paths corresponding to H/H exchange and silylation, formation of Cp(2)Ln(SiH(3)), have been computed. They both occur via a single-step sigma-bond metathesis mechanism. For the athermal H/H exchange reaction, the calculated activation barrier averages 1.8 kcal.mol(-)(1) relative to the precursor adduct Cp(2)LnH(eta(2)-SiH(4)) for all lanthanide elements. The silylation path is slightly exogenic (DeltaE approximately -6.5 kcal.mol(-1)) with an activation barrier averaging 5.2 kcal.mol(-1) relative to the precursor adduct where SiH(4) is bonded by two Si-H bonds. Both pathways are therefore thermally accessible. The H/H exchange path is calculated to be kinetically more favorable whereas the silylation reaction is thermodynamically preferred. The reactivity of this familly of lanthanide complexes with SiH(4) contrasts strongly with that obtained previously with CH(4). The considerably lower activation barrier for silylation relative to methylation is attributed to the ability of Si to become hypervalent.
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Maron L, Perrin L, Eisenstein O, Andersen RA. Are the carbon monoxide complexes of Cp(2)M (M = Ca, Eu, or Yb) carbon or oxygen bonded? An answer from DFT calculations. J Am Chem Soc 2002; 124:5614-5. [PMID: 12010015 DOI: 10.1021/ja025820l] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
DFT calculations have been performed on the CO adducts of the bivalent lanthanides, Cp(2)M(CO)(x), where M is Eu or Yb and x is 1 or 2, the alkaline earth metallocene Cp(2)Ca(CO), and the methylisocyanide adducts of Yb. The calculated nu(CO) values are in agreement with experiment for Cp(2)M(CO) when M is Ca or Eu, but in striking disagreement when the CO is bound to the metal by way of the carbon atom in CO in the case of Yb. The calculated nu(CO) values for M = Yb are brought into agreement with experiment when the CO is allowed to bond to Cp(2)Yb by way of the oxygen atom.
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Maron L, Perrin L, Eisenstein O. DFT study of CH4 activation by d0 Cl2LnZ (Z = H, CH3) complexes. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b107698c] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Yerly S, Vora S, Rizzardi P, Chave JP, Vernazza PL, Flepp M, Telenti A, Battegay M, Veuthey AL, Bru JP, Rickenbach M, Hirschel B, Perrin L. Acute HIV infection: impact on the spread of HIV and transmission of drug resistance. AIDS 2001; 15:2287-92. [PMID: 11698702 DOI: 10.1097/00002030-200111230-00010] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the impact of primary HIV infection (PHI) on the spread of HIV and the temporal trends in transmission of HIV drug resistance between 1996 and 1999 in Switzerland. METHODS Sequencing of the genes for reverse transcriptase (RT) and protease was performed for 197 individuals with documented PHI. Phylogenetic analyses were confronted with epidemiological data. RESULTS Significant clustering was demonstrated for 29% of the RT sequences. All these cases occurred closely together in place and time; contact tracing demonstrated transmission at the time of PHI in 30% of them. Genotypic drug resistance was detected in 8.6% of PHI individuals in 1996, 14.6% in 1997, 8.8% in 1998 and 5.0% in 1999. Drug-resistant variants were identified in 11.3% of individuals infected by homosexual contacts, 6.1% by heterosexual contacts, 13% of intravenous drug users and more frequently in men (10.4%) than women (2.6%). Potential factors involved in the recent decrease of transmission of drug-resistant variants include increase of HIV non-B subtypes from 23% in 1996 to 35% in 1999 (only one non-B subtype had resistance mutations) and a steady increase of patients with undetectable viraemia as documented in Swiss HIV Cohort Study (10% in 1996 vs 53% in 1999). CONCLUSIONS Phylogenetic and epidemiological analyses underline the impact of PHI in the spread of HIV. Moreover, this study indicates that drug resistance transmission may have decreased recently in Switzerland through the increased frequency of infection with HIV non-B subtypes and the steady increase of patients with undetectable viraemia.
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Perrin L, Clot E, Eisenstein O, Loch J, Crabtree RH. Computed ligand electronic parameters from quantum chemistry and their relation to Tolman parameters, Lever parameters, and Hammett constants. Inorg Chem 2001; 40:5806-11. [PMID: 11681889 DOI: 10.1021/ic0105258] [Citation(s) in RCA: 207] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The calculated (DFT, B3PW91) A(1) nu(CO) frequency in LNi(CO)(3) defines an electronic parameter that reliably predicts the relative donor powers of a wide variety of cationic, neutral, and negatively charged ligands. These calculated parameters correlate very well with the available Tolman and Lever parameters, and also with Hammett's sigma(m), where available. The method avoids any experimental limitations and, in particular, can be used for proposed ligands not yet experimentally available.
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Pilcher CD, Eron JJ, Vemazza PL, Battegay M, Harr T, Yerly S, Vom S, Perrin L. Sexual transmission during the incubation period of primary HIV infection. JAMA 2001; 286:1713-4. [PMID: 11594895 DOI: 10.1001/jama.286.14.1713] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Nicklin JL, Perrin L, Obermair A, McConachie I, Cominos D. The significance of psammoma bodies on cervical cytology smears. Gynecol Oncol 2001; 83:6-9. [PMID: 11585407 DOI: 10.1006/gyno.2001.6325] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The association between psammoma bodies on cervical smear (PBCS) and the presence of gynecological malignancy has been documented previously. The aim of this study was to determine the incidence of malignancy where psammoma bodies were detected on smear, to identify features that may be predictive of associated malignancy, and to make recommendations about management. METHODS The databases of two large private pathology laboratories were accessed to obtain details of all patients reported to have PBCS between April 1992 and May 2000. A retrospective review was then undertaken to determine if any patients were found to have gynecological malignancies. The appearances of the background cells on the cervical smear and details of clinical management were recorded and evaluated. RESULTS Twenty-two patients were found to have PBCS. Five patients were found to have a gynecological malignancy. These five patients were significantly older than the remaining patients. When these results were combined with all cases reported in the world literature, it became apparent that patients with coexisting malignancy were statistically significantly older than those not found to have malignancy (P < 0.0001). The cytological appearance of cells on the background smear was highly predictive of the presence or absence of malignancy. CONCLUSIONS There is an association between PBCS and genital tract malignancy. This association is much stronger for postmenopausal women. The background cytology is highly predictive of the presence of associated malignancy. There is a strong argument that all women with psammoma bodies on cervical smear should undergo smear review, pelvic ultrasonography, hysteroscopy and biopsy, and laparoscopy to exclude the presence of a gynecological malignancy. For younger reproductive-aged women, a negative workup is reassuring.
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Peters S, Muñoz M, Yerly S, Sanchez-Merino V, Lopez-Galindez C, Perrin L, Larder B, Cmarko D, Fakan S, Meylan P, Telenti A. Resistance to nucleoside analog reverse transcriptase inhibitors mediated by human immunodeficiency virus type 1 p6 protein. J Virol 2001; 75:9644-53. [PMID: 11559796 PMCID: PMC114535 DOI: 10.1128/jvi.75.20.9644-9653.2001] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Resistance of human immunodeficiency virus type 1 (HIV-1) to antiretroviral agents results from target gene mutation within the pol gene, which encodes the viral protease, reverse transcriptase (RT), and integrase. We speculated that mutations in genes other that the drug target could lead to drug resistance. For this purpose, the p1-p6(gag)-p6(pol) region of HIV-1, placed immediately upstream of pol, was analyzed. This region has the potential to alter Pol through frameshift regulation (p1), through improved packaging of viral enzymes (p6(Gag)), or by changes in activation of the viral protease (p6(Pol)). Duplication of the proline-rich p6(Gag) PTAP motif, necessary for late viral cycle activities, was identified in plasma virus from 47 of 222 (21.2%) patients treated with nucleoside analog RT inhibitor (NRTI) antiretroviral therapy but was identified very rarely from drug-naïve individuals. Molecular clones carrying a 3-amino-acid duplication, APPAPP (transframe duplication SPTSPT in p6(Pol)), displayed a delay in protein maturation; however, they packaged a 34% excess of RT and exhibited a marked competitive growth advantage in the presence of NRTIs. This phenotype is reminiscent of the inoculum effect described in bacteriology, where a larger input, or a greater infectivity of an organism with a wild-type antimicrobial target, leads to escape from drug pressure and a higher MIC in vitro. Though the mechanism by which the PTAP region participates in viral maturation is not known, duplication of this proline-rich motif could improve assembly and packaging at membrane locations, resulting in the observed phenotype of increased infectivity and drug resistance.
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Oxenius A, Yerly S, Ramirez E, Phillips RE, Price DA, Perrin L. Distribution of functional HIV-specific CD8 T lymphocytes between blood and secondary lymphoid organs after 8-18 months of antiretroviral therapy in acutely infected patients. AIDS 2001; 15:1653-6. [PMID: 11546939 DOI: 10.1097/00002030-200109070-00007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To assess whether drug-induced suppression of the plasma viral load is associated with selective differential distribution of virus-specific CD8 T cells between the blood and secondary lymphoid organs. METHODS HIV-specific CD8 T lymphocyte responses were quantified in matched peripheral blood and lymph node samples from seven patients starting treatment shortly after infection, who received antiretroviral therapy (ART) for a median of 14 months. Cells recovered from samples were subjected to IFN-gamma ELISPOT analysis. A series of synthetic peptides corresponding to previously characterized cytotoxic T lymphocyte epitopes restricted by HLA I molecules present in each patient were used as antigens, together with appropriate positive and negative controls. RESULTS HIV-specific CD8 T lymphocyte responses were found in six of the seven patients. The observed frequencies of HIV-specific CD8 T lymphocytes and the pattern of epitope recognition was identical within the two compartments. These results also confirm the observation that functional HIV-specific CD8 T cells are preserved on ART in most patients initiating treatment at the time of primary HIV-1 infection. CONCLUSION This investigation demonstrated that patterns of antigenic immunodominance as well as frequencies of HIV-specific CD8 T lymphocytes are similar in blood and lymphoid tissue compartments in HIV-infected individuals. These findings support current approaches to the identification of HIV-specific CD8 T lymphocyte reactivity based on leukocytes isolated from blood even in patients with ART-induced suppression of viral load.
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Yerly S, Rickenbach M, Popescu M, Taffe P, Craig C, Perrin L. Drug resistance mutations in HIV-1-infected subjects during protease inhibitor-containing highly active antiretroviral therapy with nelfinavir or indinavir. Antivir Ther 2001; 6:185-9. [PMID: 11808753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVES The aim of this retrospective study was to evaluate treatment outcome and characterize the pattern of genotype mutations in subjects with treatment failure on highly active antiretroviral therapy (HAART) containing nelfinavir or indinavir. STUDY DESIGN AND METHODS The database of the Swiss HIV Cohort Study was screened for all subjects naive to protease inhibitor (PI) treatment who started HAART with nelfinavir or indinavir, responded initially (HIV-RNA <400 copies/ml) and received >24 weeks of treatment. Responders with subsequent treatment failure (HIV-RNA >1000 copies/ml, bordered by HIV-RNA >400 copies/ml) were selected for genotypic analysis. RESULTS Initial treatment response, maintenance of response and subsequent virological failure were observed at a comparable frequency in 1143 nelfinavir and 1555 indinavir subjects. Of the treatment-naive patients, 13% who took nelfinavir and 16% who took indinavir had HIV-RNA >1000 copies/ml at least once. These values increased to 24 and 27%, respectively, for reverse transcriptase inhibitor-experienced subjects. Genotypic analysis in a subset of subjects with virological failure identified 30N as the only primary mutation in the nelfinavir subjects (8 out of 21, 38%) whereas isolated or combined 82A/T and 461/L mutations were detected in the indinavir subjects (9 out of 20, 45%). CONCLUSIONS In this population of previously PI-naive subjects, the rate of virological failure and the frequency of resistance mutations at the time of virological failure were comparable in subjects receiving nelfinavir- or indinavir-containing HAART. In nelfinavir subjects, 30N was the only primary mutation whereas isolated or combined 82A/T and 461/L mutations were detected in indinavir subjects.
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Goh LE, Perrin L, Hoen B, Cooper D, Phillips A, Janossy G, Sonnenborg A, Tsoukas C, Lampe F, Kinloch S. Study protocol for the evaluation of the potential for durable viral suppression after quadruple HAART with or without HIV vaccination: the QUEST study. HIV CLINICAL TRIALS 2001; 2:438-44. [PMID: 11673819 DOI: 10.1310/7v45-phyr-8bu6-dlun] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE By protecting and stimulating HIV-specific CD4 cell responses, treatment of primary HIV infection (PHI) with potent quadruple HAART could lead to prolonged suppression of HIV replication after cessation of antiretroviral therapy. The QUEST trial investigates this hypothesis and aims to determine whether addition of a therapeutic vaccine to HAART increases the likelihood of prolonged viral suppression compared to HAART alone. METHOD 148 patients with PHI were recruited. Participants were treated with open-label HAART for at least 76 weeks. Participants with sustained viremia <50 copies/mL were randomized to one of three 5-month, double-blinded study treatment groups: HAART alone, HAART + ALVAC-HIV (vCP1452), or HAART + ALVAC-HIV (vCP1452) + Remune. After a further month of HAART alone, all treatment was stopped where plasma HIV-1 RNA remained at <50 copies/mL. Intensive virologic and immunologic monitoring during a 24-week observation period followed treatment interruption. Patients who met treatment reintroduction criteria were offered HAART rescue.
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150
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Yerly S, Quadri R, Negro F, Barbe KP, Cheseaux JJ, Burgisser P, Siegrist CA, Perrin L. Nosocomial outbreak of multiple bloodborne viral infections. J Infect Dis 2001; 184:369-72. [PMID: 11443566 DOI: 10.1086/322036] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2001] [Revised: 04/06/2001] [Indexed: 12/15/2022] Open
Abstract
In resource-limited countries, nosocomial transmission of bloodborne pathogens is a major public health concern. After a major outbreak of human immunodeficiency virus (HIV) infection in approximately 400 children in 1998 in Libya, we tested HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV) markers in 148 children and collected epidemiological data in a subgroup of 37 children and 46 parents. HIV infection was detected in all children but one, with HCV or HBV coinfection in 47% and 33%, respectively. Vertical transmission was ruled out by analysis of parents' serology. The children visited the same hospital 1-6 times; at each visit, invasive procedures with potential blood transmission of virus were performed. HIV and HCV genotypic analyses identified a HIV monophyletic group, whereas 4 clusters of HCV sequences were identified. To our knowledge, this is the largest documented outbreak of nosocomial HIV transmission.
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