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Bogenschutz MP, Forcehimes AA, Pommy JA, Wilcox CE, Barbosa PCR, Strassman RJ. Psilocybin-assisted treatment for alcohol dependence: a proof-of-concept study. J Psychopharmacol 2015; 29:289-99. [PMID: 25586396 DOI: 10.1177/0269881114565144] [Citation(s) in RCA: 694] [Impact Index Per Article: 69.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
UNLABELLED Several lines of evidence suggest that classic (5HT2A agonist) hallucinogens have clinically relevant effects in alcohol and drug addiction. Although recent studies have investigated the effects of psilocybin in various populations, there have been no studies on the efficacy of psilocybin for alcohol dependence. We conducted a single-group proof-of-concept study to quantify acute effects of psilocybin in alcohol-dependent participants and to provide preliminary outcome and safety data. Ten volunteers with DSM-IV alcohol dependence received orally administered psilocybin in one or two supervised sessions in addition to Motivational Enhancement Therapy and therapy sessions devoted to preparation for and debriefing from the psilocybin sessions. Participants' responses to psilocybin were qualitatively similar to those described in other populations. Abstinence did not increase significantly in the first 4 weeks of treatment (when participants had not yet received psilocybin), but increased significantly following psilocybin administration (p < 0.05). Gains were largely maintained at follow-up to 36 weeks. The intensity of effects in the first psilocybin session (at week 4) strongly predicted change in drinking during weeks 5-8 (r = 0.76 to r = 0.89) and also predicted decreases in craving and increases in abstinence self-efficacy during week 5. There were no significant treatment-related adverse events. These preliminary findings provide a strong rationale for controlled trials with larger samples to investigate efficacy and mechanisms. TRIAL REGISTRATION NCT02061293.
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Clinical Trial |
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Asherson RA, Cervera R, Piette JC, Shoenfeld Y, Espinosa G, Petri MA, Lim E, Lau TC, Gurjal A, Jedryka-Góral A, Chwalinska-Sadowska H, Dibner RJ, Rojas-Rodríguez J, García-Carrasco M, Grandone JT, Parke AL, Barbosa P, Vasconcelos C, Ramos-Casals M, Font J, Ingelmo M. Catastrophic antiphospholipid syndrome: clues to the pathogenesis from a series of 80 patients. Medicine (Baltimore) 2001; 80:355-77. [PMID: 11704713 DOI: 10.1097/00005792-200111000-00002] [Citation(s) in RCA: 254] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Case Reports |
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Staprans SI, Hamilton BL, Follansbee SE, Elbeik T, Barbosa P, Grant RM, Feinberg MB. Activation of virus replication after vaccination of HIV-1-infected individuals. J Exp Med 1995; 182:1727-37. [PMID: 7500017 PMCID: PMC2192265 DOI: 10.1084/jem.182.6.1727] [Citation(s) in RCA: 223] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Little is known about the factors that govern the level of HIV-1 replication in infected individuals. Recent studies (using potent antiviral drugs) of the kinetics of HIV-1 replication in vivo have demonstrated that steady-state levels of viremia are sustained by continuous rounds of de novo infection and the associated rapid turnover of CD4+ T lymphocytes. However, no information is available concerning the biologic variables that determine the size of the pool of T cells that are susceptible to virus infection or the amount of virus produced from infected cells. Furthermore, it is not known whether all CD4+ T lymphocytes are equally susceptible to HIV-1 infection at a given time or whether the infection is focused on cells of a particular state of activation or antigenic specificity. Although HIV-1 replication in culture is known to be greatly facilitated by T cell activation, the ability of specific antigenic stimulation to augment HIV-1 replication in vivo has not been studied. We sought to determine whether vaccination of HIV-1-infected adults leads to activation of virus replication and the targeting of vaccine antigen-responsive T cells for virus infection and destruction. Should T cell activation resulting from exposure to environmental antigens prove to be an important determinant of the steady-state levels of HIV-1 replication in vivo and lead to the preferential loss of specific populations of CD4+ T lymphocytes, it would have significant implications for our understanding of and therapeutic strategies for HIV-1 disease. To begin to address these issues, HIV-1-infected individuals and uninfected controls were studied by measurement of immune responses to influenza antigens and quantitation of virion-associated plasma HIV-1 RNA levels at baseline and at intervals after immunization with the trivalent influenza vaccine. Influenza vaccination resulted in readily demonstrable but transient increases in plasma HIV-1 RNA levels, indicative of activation of viral replication, in HIV-1-infected individuals with preserved ability to immunologically respond to vaccine antigens. Activation of HIV-1 replication by vaccination was more often seen and of greater magnitude in individuals who displayed a T cell proliferative response to vaccine antigens at baseline and in those who mounted a significant serologic response after vaccination. The fold increase in viremia, as well as the rates of increase of HIV-1 in plasma after vaccination and rates of viral decline after peak viremia, were higher in individuals with higher CD4+ T cell counts.(ABSTRACT TRUNCATED AT 400 WORDS)
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Spinoni J, Vogt JV, Naumann G, Barbosa P, Dosio A. Will drought events become more frequent and severe in Europe? INTERNATIONAL JOURNAL OF CLIMATOLOGY 2018. [PMID: 0 DOI: 10.1002/joc.5291] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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174 |
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Stireman JO, Dyer LA, Janzen DH, Singer MS, Lill JT, Marquis RJ, Ricklefs RE, Gentry GL, Hallwachs W, Coley PD, Barone JA, Greeney HF, Connahs H, Barbosa P, Morais HC, Diniz IR. Climatic unpredictability and parasitism of caterpillars: implications of global warming. Proc Natl Acad Sci U S A 2005; 102:17384-7. [PMID: 16293686 PMCID: PMC1283988 DOI: 10.1073/pnas.0508839102] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar-parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps suggests that climatic variability impairs the ability of parasitoids to track host populations. Given the important role of parasitoids in regulating insect herbivore populations in natural and managed systems, we predict an increase in the frequency and intensity of herbivore outbreaks through a disruption of enemy-herbivore dynamics as climates become more variable.
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Research Support, U.S. Gov't, Non-P.H.S. |
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Barbosa PCR, Mizumoto S, Bogenschutz MP, Strassman RJ. Health status of ayahuasca users. Drug Test Anal 2012; 4:601-9. [DOI: 10.1002/dta.1383] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 05/15/2012] [Accepted: 05/15/2012] [Indexed: 11/09/2022]
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Barbosa PCR, Giglio JS, Dalgalarrondo P. Altered States of Consciousness and Short-Term Psychological After-Effects Induced by the First Time Ritual Use of Ayahuasca in an Urban Context in Brazil. J Psychoactive Drugs 2005; 37:193-201. [PMID: 16149333 DOI: 10.1080/02791072.2005.10399801] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
This report describes psychological assessments of the first time ritual use of ayahuasca in the religious groups União do Vegetal and Santo Daime. Nineteen subjects who tried the beverage in Santo Daime rituals and nine subjects who tried it in União do Vegetal rituals were evaluated one to four days before their first ayahuasca experience in life and one to two weeks after this experience. Semistructured interviews and a structured psychiatric scale were used in the first evaluation to elicit set variables concerning attitudes towards the ayahuasca experience and to elicit mental health status. Mental health status was reassessed in the second evaluation, which also included a semistructured interview concerning the phenomenology of altered states of consciousness (ASCs). Predominantly positive expectancies concerning the ayahuasca experience were the most prominent findings concerning set variables. Visual phenomena, numinousness, peacefulness, insights and a distressing reaction were the most salient ASC experiences. A significant reduction of the intensity of minor psychiatric symptoms occurred in the Santo Daime group after the hallucinogen experience. Subjects in both groups reported behavioral changes towards assertiveness, serenity and vivacity/joy. The set and setting hypothesis, suggestibility processes, as well as the supposed unique effects of ayahuasca are used in discussing these findings.
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Harrer E, Harrer T, Barbosa P, Feinberg M, Johnson RP, Buchbinder S, Walker BD. Recognition of the highly conserved YMDD region in the human immunodeficiency virus type 1 reverse transcriptase by HLA-A2-restricted cytotoxic T lymphocytes from an asymptomatic long-term nonprogressor. J Infect Dis 1996; 173:476-9. [PMID: 8568316 DOI: 10.1093/infdis/173.2.476] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The human immunodeficiency virus (HIV) type 1 reverse transcriptase (RT) is an important target for therapeutic intervention and for HIV-1-specific cytotoxic T lymphocytes (CTL). An HLA-A2-restricted CTL epitope containing the sequence YMDD, which is highly conserved among human and animal retroviruses and essential for function of the RNA-dependent DNA polymerase, is identified. The drug resistance mutation at RT amino acid 184 (M184V), associated with (-)-2'-deoxy-3'-thiacytidine (lamivudine), (-)-2'-deoxy-5-fluoro-3'-thiacytidine (FTC), and dideoxyinosine resistance, is located within this epitope and abolishes recognition by an established CTL response. This study demonstrates that the CTL response may target functionally relevant regions of the RT protein and suggests drug therapy may select for viral variants with altered susceptibility to established cellular immune responses.
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Spinoni J, Barbosa P, De Jager A, McCormick N, Naumann G, Vogt JV, Magni D, Masante D, Mazzeschi M. A new global database of meteorological drought events from 1951 to 2016. JOURNAL OF HYDROLOGY. REGIONAL STUDIES 2019. [PMID: 32257820 DOI: 10.1016/j.ejrh.2015.01.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
STUDY REGION This study has three spatial scales: global (0.5°), macro-regional, and country scale. The database of drought events has specific entries for each macro-region and country. STUDY FOCUS We constructed a database of meteorological drought events from 1951 to 2016, now hosted by the Global Drought Observatory of the European Commission's Joint Research Centre. Events were detected at macro-regional and country scale based on the separate analysis of the Standardized Precipitation-Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) at different accumulation scales (from 3 to 72 months), using as input the Global Precipitation Climatology Centre (GPCC) and Climatic Research Unit (CRU) Time Series datasets. The database includes approximately 4800 events based on SPEI-3 and 4500 based on SPI-3. Each event is described by its start and end date, duration, intensity, severity, peak, average and maximum area in drought, and a special score to classify 52 mega-droughts. NEW HYDROLOGICAL INSIGHTS FOR THE REGION UNDER STUDY We derived trends in drought frequency and severity, separately for SPI and SPEI at a 12-month accumulation scale, which is usually related to hydrological droughts. Results show several drought hotspots in the last decades: Amazonia, southern South America, the Mediterranean region, most of Africa, north-eastern China and, to a lesser extent, central Asia and southern Australia. Over North America, central Europe, central Asia, and Australia, the recent progressive temperature increase outbalanced the increase in precipitation causing more frequent and severe droughts.
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Bottrell DG, Barbosa P, Gould F. Manipulating natural enemies by plant variety selection and modification: a realistic strategy? ANNUAL REVIEW OF ENTOMOLOGY 1998; 43:347-367. [PMID: 15012394 DOI: 10.1146/annurev.ento.43.1.347] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The host plants of arthropod pests may affect parasitoids and predators directly or indirectly, through multitrophic interactions. Direct plant effects may involve simple mechanisms such as reduced parasitoid searching efficiency caused by trichomes. Multitrophic effects often involve complex interactions that are not well understood, and their impact on natural enemies and biological control are difficult to predict. Knowledge of the direct and multitrophic effects creates opportunities to increase the effectiveness of natural enemies by incorporating natural enemy-enhancing traits into crop plants. The strategy may have potential for both generalist and specialist natural enemies, but the enemies' behavior and other factors will affect the results. Although combining natural enemies and plant resistance may slow the adaptation of some insect pests, it may speed up adaptations of others. A better understanding of plant/pest/natural enemy evolution is necessary to predict how to combine natural enemies and plant resistance for the best long-term results.
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Barbosa PCR, Cazorla IM, Giglio JS, Strassman R. A Six-Month Prospective Evaluation of Personality Traits, Psychiatric Symptoms and Quality of Life in Ayahuasca-Naïve Subjects. J Psychoactive Drugs 2009; 41:205-12. [DOI: 10.1080/02791072.2009.10400530] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Barbosa P, Charneau P, Dumey N, Clavel F. Kinetic analysis of HIV-1 early replicative steps in a coculture system. AIDS Res Hum Retroviruses 1994; 10:53-9. [PMID: 8179964 DOI: 10.1089/aid.1994.10.53] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
During an acute human immunodeficiency virus (HIV) infection in vitro, different forms of unintegrated viral DNA accumulate in target cells. They include linear full-length HIV DNA molecules, which are the precursors of the integrated provirus, and two types of circular molecules (with one or two LTRs), whose role and mode of formation are not fully understood. To evaluate the intracellular fate of HIV unintegrated DNA, and to follow the formation of the two types of circular DNA molecules, the nuclear transport of viral DNA, and its integration in host cell DNA, we have designed a "DNA chase" assay. This assay is based on cocultivation of persistently HIV-1-infected H9 cells with uninfected MT4, allowing rapid accumulation of viral DNA, which is then blocked by addition of AZT. In this highly efficient, synchronous, one-step cycle infection system, HIV linear DNA can be detected on Southern blots as early as 4 hr after the start of the coculture. Subsequently, viral DNA that had been synthesized before the addition of AZT could be "chased," establishing that almost all linear DNA molecules are rapidly transported to the nucleus, where they are either processed into the two types of circles or integrated. We could estimate that from the number of viral DNA molecules synthesized in 6 hr in this system, at least a third will become integrated and another third will circularize within 24 hr.
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Barbosa PCR, Tófoli LF, Bogenschutz MP, Hoy R, Berro LF, Marinho EAV, Areco KN, Winkelman MJ. Assessment of Alcohol and Tobacco Use Disorders Among Religious Users of Ayahuasca. Front Psychiatry 2018; 9:136. [PMID: 29740355 PMCID: PMC5928846 DOI: 10.3389/fpsyt.2018.00136] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/29/2018] [Indexed: 12/29/2022] Open
Abstract
The aims of this study were to assess the impact of ceremonial use of ayahuasca-a psychedelic brew containing N,N-dimethyltryptamine (DMT) and β-carboline -and attendance at União do Vegetal (UDV) meetings on substance abuse; here we report the findings related to alcohol and tobacco use disorder. A total of 1,947 members of UDV 18+ years old were evaluated in terms of years of membership and ceremonial attendance during the previous 12 months. Participants were recruited from 10 states from all major regions of Brazil. Alcohol and tobacco use was evaluated through questionnaires first developed by the World Health Organization and the Substance Abuse and Mental Health Services Administration. Analyses compared levels of alcohol and tobacco use disorder between the UDV and a national normative sample (n = 7,939). Binomial tests for proportions indicated that lifetime use of alcohol and tobacco was higher in UDV sample compared to the Brazilian norms for age ranges of 25-34 and over 34 years old, but not for the age range of 18-24 years old. However, current use disorders for alcohol and tobacco were significantly lower in the UDV sample than the Brazilian norms. Regression analyses revealed a significant impact of attendance at ayahuasca ceremonies during the previous 12 months and years of UDV membership on the reduction of alcohol and tobacco use disorder.
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research-article |
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Thorpe KW, Barbosa P. Effects of comsumption of high and low nicotine tobacco byManduca sexta (Lepidoptera: Sphingidae) on survival of gregarious endoparasitoidCotesia congregata (Hymenoptera: Braconidae). J Chem Ecol 2013; 12:1329-37. [PMID: 24307112 DOI: 10.1007/bf01012352] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/1985] [Accepted: 12/17/1985] [Indexed: 10/25/2022]
Abstract
The significance of nicotine in the three trophic level interaction involving tobacco (Nicotiana tabacum), the tobacco hornworm (Manduca sexta), and the parasitoidCotesia congregata was investigated in field plots of two varieties of tobacco which had about a 10-fold difference in their nicotine content. WhileM. sexta mortality, rates of parasitism byC. congregata, and the total number ofC. congregata larvae produced per host were similar on each of the two varieties, the number of parasitoids reaching adult-hood on the low nicotine treatment was nearly twice that on the high nicotine treatment. This difference was due to the significantly greater proportion of parasitoid larvae which failed to emerge from the host or that died prior to pupation after emerging from hosts which fed on the high nicotine variety. A greater proportion of larvae from hosts which fed on the low nicotine tobacco died as pupae. No treatment differences occurred for either sex of the parasitoid in individual dry weight, longevity, or pupal development time, except that female pupal duration was prolonged in the high nicotine treatment. These results support the suggestion that plant allelochemicals, which may function to provide plant resistance against pest herbivores, can be detrimental to natural enemies of the pest.
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Journal Article |
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Barbosa P, Peters TM. The effects of vital dyes on living organisms with special reference to methylene blue and neutral red. THE HISTOCHEMICAL JOURNAL 1971; 3:71-93. [PMID: 4106597 DOI: 10.1007/bf01686508] [Citation(s) in RCA: 50] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Historical Article |
54 |
50 |
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Carvalheiras G, Vita P, Marta S, Trovão R, Farinha F, Braga J, Rocha G, Almeida I, Marinho A, Mendonça T, Barbosa P, Correia J, Vasconcelos C. Pregnancy and systemic lupus erythematosus: review of clinical features and outcome of 51 pregnancies at a single institution. Clin Rev Allergy Immunol 2010; 38:302-6. [PMID: 19603147 DOI: 10.1007/s12016-009-8161-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Systemic lupus erythematosus (SLE) is mainly a disease of fertile women and the coexistence of pregnancy is by no means a rare event. How SLE and its treatment affects pregnancy outcome is still a matter of debate. Assessment of the reciprocal clinical impact of SLE and pregnancy was investigated in a cohort study. We reviewed the clinical features, treatment, and outcomes of 43 pregnant SLE patients with 51 pregnancies followed from 1993 to 2007 at a tertiary university hospital. The age of patients was 28.7 +/- 5.4 years and SLE was diagnosed at age of 23.0 +/- 6.1 years. Previous manifestations of SLE included lupus nephritis (14 patients) and secondary antiphospholipid syndrome (11 patients). Thirty-five pregnant patients (69%) were in remission for more than 6 months at the onset of pregnancy. Patients were being treated with low doses of prednisone (29), hydroxychloroquine (20), azathioprine (five), acetylsalicylic acid (51), and low molecular weight heparin (13). Sixteen pregnancy-associated flares were documented, mainly during the second trimester (42%) and also in the following year after delivery (25%). Renal involvement was found in 11 cases (68%). Spontaneous abortion occurred in 6%, 16% had premature deliveries, and 74% were delivered at term. No cases of maternal mortality occurred. No cases of fetal malformation were recorded. There was one intrauterine fetal death and one neonatal death at 24 gestational weeks. Pregnant women with SLE are high risk patients, but we had a 90% success rate in our cohort. A control disease activity strategy to target clinical remission is essential.
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Review |
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45 |
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Pereira JMC, Pereira BS, Barbosa P, Stroppiana D, Vasconcelos MJP, Grégoire JM. Satellite monitoring of fire in the EXPRESSO study area during the 1996 dry season experiment: Active fires, burnt area, and atmospheric emissions. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999jd900422] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Sinclair E, Barbosa P, Feinberg MB. The nef gene products of both simian and human immunodeficiency viruses enhance virus infectivity and are functionally interchangeable. J Virol 1997; 71:3641-51. [PMID: 9094638 PMCID: PMC191513 DOI: 10.1128/jvi.71.5.3641-3651.1997] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Adult rhesus macaques infected with nef-defective simian immunodeficiency virus (SIV) exhibit extremely low levels of steady-state virus replication, do not succumb to immunodeficiency disease, and are protected from experimental challenge with pathogenic isolates of SIV. Similarly, rare humans found to be infected with nef-defective human immunodeficiency virus type 1 (HIV-1) variants display exceptionally low viral burdens and do not show evidence of disease progression after many years of infection. HIV-1 Nef induces the rapid endocytosis and lysosomal degradation of cell surface CD4 and enhances virus infectivity in primary human T cells and macrophages. Although expression of SIV Nef also leads to down-modulation of cell surface CD4 levels, no evidence for SIV Nef-induced enhancement of virus infectivity was observed in earlier studies. Thus, it remains unclear whether fundamental differences exist between the activities of HIV-1 and SIV Nef. To establish more clearly whether the SIV and HIV-1 nef gene products are functionally analogous, we compared the replication kinetics and infectivity of variants of SIVmac239 that either do (SIVnef+) or do not (SIV delta nef) encode intact nef gene products. SIVnef+ replicates more rapidly than nef-defective viruses in both human and rhesus peripheral blood mononuclear cells (PBMCs). As previously described for HIV-1 Nef, SIV Nef also enhances virus infectivity within each cycle of virus replication. As a strategy for evaluating the in vivo contribution of HIV-1 nef alleles and long terminal repeat regulatory sequences to the pathogenesis of immunodeficiency disease, we constructed SIV-HIV chimeras in which the nef coding and U3 regulatory regions of SIVmac239 were replaced by the corresponding regions from HIV-1/R73 (SIVR7nef+). SIVR7nef+ displays enhanced infectivity and accelerated replication kinetics in primary human and rhesus PBMC infections compared to its nef-defective counterpart. Converse chimeras, containing SIV Nef in an HIV-1 background (R7SIVnef+) also exhibit greater infectivity than matched nef-defective viruses (R7SIV delta nef). These data indicate that SIV Nef, like that of HIV-1, does enhance virus replication in primary cells in tissue culture and that HIV-1 and SIV Nef are functionally interchangeable in the context of both HIV-1 and SIV.
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research-article |
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Martins L, Rocha G, Rodrigues A, Santos J, Vasconcelos C, Correia J, Farinha F, Almeida I, Barbosa P, Guimarães S. Lupus nephritis: a retrospective review of 78 cases from a single center. Clin Nephrol 2002; 57:114-9. [PMID: 11863120 DOI: 10.5414/cnp57114] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
UNLABELLED Lupus nephritis (LN) is a frequent and serious manifestation of systemic lupus erythematosus. However, the outcome has progressively improved in the last 3 decades and this was due to more efficient and early treatment of LN and comorbid situations. The aim of our study was to analyze our experience and outcome in LN, to evaluate clinicopathologic and clinicolaboratory correlations and to search for risk factors for renal and patient survival. PATIENTS AND METHODS We conducted a retrospective study of 78 patients with biopsy-proven LN. RESULTS Acute renal failure and subnephrotic proteinuria with microhematuria occurred each one in 39.7% of the patients, nephrotic syndrome in 16.7% and nephritic syndrome in 3.8%. The mean serum creatinine at presentation was 1.45 +/- 1.03 mg/dl and the creatinine clearance was 68.2 +/- 40.3 ml/min. Class IV LN existed in 71.8%, Class III in 20.5%, Class V in 6.4% and Class VI in 1.3%. The treatment included steroids and cytotoxic agents in 87.5% of the patients with proliferative LN. Hypertension, serum creatinine and acute renal failure at presentation, as well as significant chronicity on renal biopsy, were significantly correlated with the progression to chronic renal failure in our population. Males were more prone to develop renal flares. 3.8% of the patients died, 9% lost their renal function, 26.9% are in remission, 33.3% still have subnephrotic proteinuria and microhematuria, 7.7% have nephrotic syndrome and 19.2% have chronic renal failure. The mean global follow-up was 102 +/- 74 months and 96.2% of the patients survived. The actuarial renal survival was 96.1% in the first year; 89.9% at 5 years; and 83.7% at 10 and 20 years. CONCLUSION We can say that hypertension, serum creatinine and acute renal failure at the onset and significant chronicity on renal biopsy, proved to be risk factors for chronic renal failure in our study population. Male gender was a risk factor for renal flares. The achieved global outcome can be considered a good result.
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Barbosa MD, Rebelo O, Barbosa P, Gonçalves J, Fernandes R. Cystic intraventricular schwannoma: case report and review of the literature. Neurocirugia (Astur) 2002; 12:56-60. [PMID: 11706436 DOI: 10.1016/s1130-1473(01)70719-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Intraventricular schwannoma is an exceedingly rare tumour with only 6 cases described in the literature. One case of a cystic intraventricular schwannoma operated on at our Institution is analyzed and the other cases reported in the literature are reviewed. Complete removal was achieved and no recurrence was noted after a follow-up period of 10 years. Intraventricular schwannomas are rare tumours that are amenable to complete surgical removal, having a good prognosis without the need of adjuvant therapy.
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Case Reports |
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Raupp MJ, Milan FR, Barbosa P, Leonhardt BA. Methylcyclopentanoid Monoterpenes Mediate Interactions Among Insect Herbivores. Science 1986; 232:1408-10. [PMID: 17828917 DOI: 10.1126/science.232.4756.1408] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Beetles secrete an array of chemicals generally believed to mitigate attack by predators. Methylcyclopentanoid monoterpenes secreted by larvae of the willow leaf beetle, Plagiodera versicolora, deter feeding by conspecific adults. Furthermore, the secretion elicits a strong repugnancy response in larvae of another willow herbivore, Nymphalis antiopa. Leaves bearing beetle larvae are less likely than leaves not bearing beetles to be frequented and consumed by Nymphalis larvae. Predator defense may not be the sole function of glandular secretions produced by herbivorous insects; secretions may also mediate interactions among herbivores that use a common resource.
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Spinoni J, Barbosa P, De Jager A, McCormick N, Naumann G, Vogt JV, Magni D, Masante D, Mazzeschi M. A new global database of meteorological drought events from 1951 to 2016. JOURNAL OF HYDROLOGY. REGIONAL STUDIES 2019; 22:100593. [PMID: 32257820 PMCID: PMC7099764 DOI: 10.1016/j.ejrh.2019.100593] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/25/2019] [Accepted: 01/25/2019] [Indexed: 04/29/2023]
Abstract
STUDY REGION This study has three spatial scales: global (0.5°), macro-regional, and country scale. The database of drought events has specific entries for each macro-region and country. STUDY FOCUS We constructed a database of meteorological drought events from 1951 to 2016, now hosted by the Global Drought Observatory of the European Commission's Joint Research Centre. Events were detected at macro-regional and country scale based on the separate analysis of the Standardized Precipitation-Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) at different accumulation scales (from 3 to 72 months), using as input the Global Precipitation Climatology Centre (GPCC) and Climatic Research Unit (CRU) Time Series datasets. The database includes approximately 4800 events based on SPEI-3 and 4500 based on SPI-3. Each event is described by its start and end date, duration, intensity, severity, peak, average and maximum area in drought, and a special score to classify 52 mega-droughts. NEW HYDROLOGICAL INSIGHTS FOR THE REGION UNDER STUDY We derived trends in drought frequency and severity, separately for SPI and SPEI at a 12-month accumulation scale, which is usually related to hydrological droughts. Results show several drought hotspots in the last decades: Amazonia, southern South America, the Mediterranean region, most of Africa, north-eastern China and, to a lesser extent, central Asia and southern Australia. Over North America, central Europe, central Asia, and Australia, the recent progressive temperature increase outbalanced the increase in precipitation causing more frequent and severe droughts.
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Abramson RD, Barbosa P, Kalumuck K, O'Brien WE. Characterization of the human argininosuccinate lyase gene and analysis of exon skipping. Genomics 1991; 10:126-32. [PMID: 2045097 DOI: 10.1016/0888-7543(91)90492-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A cosmid clone containing the entire human argininosuccinate lyase gene was isolated and characterized. The gene is approximately 35 kb in length and is divided into 16 exons. The sequence surrounding all splice sites was determined, and one unusual 5' splice site sequence in which a GC dinucleotide occurred instead of the consensus GT dinucleotide was observed. The exon structure of the gene is identical to that of the rat and similar to that of the delta-crystallin genes in the chicken. The transcription initiation site was identified, and 252 bases 5' of that site were sequenced. Within that region, the GC content is 75%, no TATA element was observed, and multiple potential Spl and CACCC binding sites were noted. Also, a putative consensus sequence that may play a role in the regulation of urea cycle genes was identified within this region. Analysis of the structure of the mature mRNA derived from this gene revealed that the sequences encoded by exon seven were deleted in approximately 5-10% of the mature mRNA in all tissue sources examined.
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Vasconcelos C, Carvalho C, Leal B, Pereira C, Bettencourt A, Costa PP, Marinho A, Barbosa P, Almeida I, Farinha F, Mendonça T, Correia JA, Mendonça D, Martins B. HLA in Portuguese Systemic Lupus Erythematosus Patients and Their Relation to Clinical Features. Ann N Y Acad Sci 2009; 1173:575-80. [DOI: 10.1111/j.1749-6632.2009.04873.x] [Citation(s) in RCA: 19] [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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Patejunas G, Barbosa P, Lacombe M, O'Brien WE. Exploring the role of histidines in the catalytic activity of duck delta-crystallins using site-directed mutagenesis. Exp Eye Res 1995; 61:151-4. [PMID: 7556478 DOI: 10.1016/s0014-4835(05)80034-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The duck delta 2-crystallin gene encodes an enzymatically-active argininosuccinate lyase while the delta 1-crystallin gene product, although 94% identical, is enzymatically inactive. Four histidine residues in the duck delta 2-crystallin. His91, His110, His162 and His178, were converted to asparagine residues in an effort to define the role of histidines in the catalytic process of this enzyme-crystallin and to explain the lack of enzyme activity in the delta 1-crystallin protein. The recombinant mutant proteins were expressed in E. coli and purified to homogeneity for analysis. These four residues were chosen because they fall within highly conserved regions of argininosuccinate lyases from several species. This analysis revealed that change of His91 or His162 for asparagine resulted in complete loss of activity. The His110 enzyme had a reduced Vmax and the His178 enzyme was near normal in its kinetic properties. These data confirm the roles of histidine in the catalytic process of this enzyme-crystallin and suggest that the change of His91 to Gln91 observed in the duck and chicken delta 1-crystallin molecules may be sufficient to account for the lack of enzymatic activity of those proteins.
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