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1.
Ecol Evol ; 13(1): e9733, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36694545

RESUMO

Deciphering the spatial patterns of alpine treelines is critical for understanding the ecosystem processes involved in the persistence of tree species and their altitudinal limit. Treelines are thought to be controlled by temperature, and other environmental variables but they have rarely been investigated in regions with different land-use change legacies. Here, we systematically investigated treeline elevation in the Apennines (Italy) and Southern Alps (New Zealand) with contrasting human history but similar biogeographic trajectories, intending to identify distinct drivers that affect their current elevation and highlight their respective peculiarities. Over 3622 km of Apennines, treeline elevation was assessed in 302 mountain peaks and in 294 peaks along 4504 km of Southern Alps. The major difference between the Southern Alps and Apennines treeline limit is associated with their mountain aspects. In the Southern Alps, the scarcely anthropized Nothofagus treeline elevation was higher on the warmer equator-facing slopes than on the pole-facing ones. Contrary to what would be expected based on temperature limitation, the elevation of Fagus sylvatica treelines in the Apennines was higher on colder, pole-facing slopes than on human-shaped equator-facing, warmer mountainsides. Pervasive positive correlations were found between treeline elevation and temperature in the Southern Alps but not in the Apennines. While the position of the Fagus and Nothofagus treelines converge on similar isotherms of annual average temperature, a striking isothermal difference between the temperatures of the hottest month on which the two taxonomic groups grow exists. We conclude that actual treeline elevation reflects the ecological processes driven by a combination of local-scale topoclimatic conditions, and human disturbance legacy. Predicting dynamic processes affecting current and future alpine treeline position requires further insight into the modulating influences that are currently understood at a regional scale.

2.
AIDS ; 20(9): 1253-60, 2006 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-16816553

RESUMO

OBJECTIVE: To study the impact of occult hepatitis B virus (HBV) infection in 115 consecutive anti-HIV-positive, hepatitis B surface antigen-negative patients, naive for antiretroviral treatment. METHODS: Of these 115, 86 patients were followed for at least 6 months (range 6-36) with serial determinations of HIV RNA and HBV DNA by polymerase chain reaction and other laboratory tests. RESULTS: Of the 86 patients having a follow-up, plasma HBV DNA was detected in 17 (19.8%), 13 on admission and four during follow-up. HBV DNA was more frequently found in patients with isolated anti-hepatitis B core (HBc; 35.5% of 31 cases) than in those lacking anti-HBc and anti-hepatitis B surface (8.8% of 41, P < 0.005), or showing both (21.4% of 14). Twenty-eight patients (32.5%) experienced a hepatic flare during the follow-up; this event was more frequent in the 17 HBV-DNA-positive patients than in the 69 negative (64.7% versus 24.6%, P < 0.005). Of the 13 HBV-DNA-positive patients on admission, 11 receiving HAART containing lamivudine became HBV-DNA negative, but two of these again became positive and experienced a hepatic flare during treatment and two both during and after lamivudine treatment. A hepatic flare also occurred under lamivudine treatment in two of the four patients in whom HBV DNA became detectable during follow-up. The role of immune reconstitution inflammatory syndrome and HAART in inducing a hepatic flare was found to be marginal in 49 patients with no HBV or hepatitis C virus marker. CONCLUSION: The study suggests that HBV occult infection, relatively frequent in anti-HIV-positive patients, is associated with hepatic flares.


Assuntos
Infecções por HIV/complicações , HIV-1 , Vírus da Hepatite B , Hepatite B/complicações , Adulto , Terapia Antirretroviral de Alta Atividade , Antivirais/uso terapêutico , Contagem de Linfócito CD4 , Distribuição de Qui-Quadrado , DNA Viral/sangue , Feminino , Citometria de Fluxo , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/genética , HIV-1/imunologia , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/sangue , Fatores de Risco
3.
Vector Borne Zoonotic Dis ; 13(10): 769-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23808978

RESUMO

During an outbreak of sheep anthrax in Basilicata, southern Italy, the owner of a flock located about 3 km away from the affected farm developed skin lesions attributable to cutaneous anthrax. The DNA extracted from the human scabs confirmed the diagnosis, and a 15-loci multiple locus variable number tandem repeat (VNTR) analysis (MLVA) following single-nucleotide repeat (SNR) analysis yielded the same genotype as that found in the dead sheep. The breeder, who had not had contact with infected or dead animals, reported having been stung by gadflies.


Assuntos
Antraz/transmissão , Bacillus anthracis/isolamento & purificação , Surtos de Doenças , Doenças dos Ovinos/transmissão , Dermatopatias Bacterianas/transmissão , Animais , Antraz/epidemiologia , Antraz/microbiologia , Bacillus anthracis/genética , Genótipo , Humanos , Itália/epidemiologia , Repetições Minissatélites/genética , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Dermatopatias Bacterianas/epidemiologia , Dermatopatias Bacterianas/microbiologia , Zoonoses
4.
J Infect Dis ; 189(11): 1983-7, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15143463

RESUMO

The association between minor mutations in human immunodeficiency virus (HIV) protease at baseline and development of common primary mutation 90M at virological failure (conferring some resistance to all protease inhibitors [PIs]) was evaluated in 93 previously drug-naive patients experiencing failure of their first PI-based antiretroviral regimens. In logistic regression analysis, the probability of accumulating a new 90M mutation at virological failure was associated with the presence at baseline of minor mutation 36I (naturally occurring in approximately 25% of HIV clade B and in >80% of HIV non-clade-B viruses) (adjusted odds ratio, 13.5 [95% confidence interval, 1.89-95.6]; P=.009) and, possibly, of 10I/V. This suggests a potential role for the presence of 36I at baseline in predicting the appearance of 90M at virological failure.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Protease de HIV/genética , HIV/enzimologia , Inibidores da Transcriptase Reversa/farmacologia , Estudos de Coortes , Farmacorresistência Viral/genética , Feminino , HIV/genética , Infecções por HIV/virologia , Protease de HIV/metabolismo , Inibidores da Protease de HIV/uso terapêutico , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Mutação Puntual , RNA Viral/química , RNA Viral/genética , Inibidores da Transcriptase Reversa/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
5.
J Acquir Immune Defic Syndr ; 34(2): 184-90, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14526207

RESUMO

Objectives of the study were to assess the differences between sexes in the likelihood of starting antiretroviral therapy (ART), in rates of sustained discontinuation from highly active antiretroviral therapy (HAART), and in clinical progression. In a multicenter cohort study (I.Co.N.A. Study), 2323 men and 1335 women previously naive to antiretrovirals were enrolled. As of September 2002, 807 women and 1480 men started ART. The median time to starting ART was 28 weeks for women and 17 weeks for men (P = 0.0003 by log-rank test). This difference was no longer significant after adjusting for either HIV RNA (P = 0.21) or CD4 count (P = 0.28) at enrollment. Women tend to start HAART less frequently than mono/dual ART after adjusting for potential confounders (odds ratio = 0.78, 95% confidence interval [CI]: 0.60-1.01; P = 0.06). Women who started HAART were 1.4 times more likely than men (95% CI: 1.00-1.99; P = 0.05) to interrupt at least 1 drug because of toxicity. Twenty-one percent of women and 19% of men interrupted HAART altogether for more than 3 months (P = 0.3). Clinical progression was observed in 53 women (22.6%) and 137 men (23.4%; P = 0.56). Risk of developing a clinical event was found to be no different between women and men (relative hazard = 0.84, 95% CI: 0.56-1.26; P = 0.40).


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Síndrome da Imunodeficiência Adquirida/imunologia , Adolescente , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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