Epidemiology of HIV-1 subtypes in an urban area of northern Italy

The distribution of the different subtypes of HIV varies from one region of the world to another. Subtype B is predominant in Europe and the USA, but there has been a gradual increase in non-B subtypes as a result of migration from regions where they are endemic, and this may have important implications for the control of HIV-1. The aim of this study was to assess the prevalence of HIV-1 subtypes in an urban area of northern Italy in the period 1997-2008. Forty-nine (12.2%; 95% CI, 9.00-15.40) of 401 patients investigated carried a non-B subtype, the prevalence of which was 7.7% (95% CI, 4.96-10.44) among native Italians and 55.3% (95% CI, 39.49-71.11) among non-Italians, 1.6% (95% CI, 0.00-3.81) among ex-intravenous drug addicts, 7.6% (95% CI, 1.21-13.99) among homosexual/bisexual men and 20.5% (95% CI, 14.83-26.17) among heterosexuals, 6.8% (95% CI, 3.37-10.23) among Italians infected as a result of sexual contacts in Italy, and 55.0% (95% CI, 33.20-76.80) among Italians infected abroad or by foreign partners. Overall prevalence increased from 2.9% (95% CI, 0.00-6.11) before 1993 to 23.0% (95% CI, 16.31-29.69) in the period 2001-2008. The results demonstrate that there has been an increase in non-B subtypes (especially sexually transmitted infections), particularly among patients infected abroad or by foreign partners.

Evolution of HVR-1 Quasispecies after 1-Year Treatment in HIV/HCV-Coinfected Patients According to the Pattern of Response to Highly Active Antiretroviral Therapy

Hepatitis C virus (HCV) variability is mainly attributed to the ability of the virus to respond to host immune pressure, acting as a driving force for the evolution of quasispecies. This study was aimed at studying the changes in HVR-1 heterogeneity and the evolution of HCV quasispecies in HIV/HCV-coinfected patients according to the pattern of response to highly active antiretroviral therapy (HAART).

Sixteen HIV/HCV-coinfected patients harbouring HCV genotype 1 and who had been on HAART for at least 1 year, 8 showing increasing CD4+T-cell counts (immunological responders) and 8 showing a stable or decreasing CD4+ T-cell counts (immunological non-responders), were selected from a prospective cohort study.

After 1 year of HAART, 11 patients showed HIV viral load <2.6 log10 cp/ml (virological responders), and 5 showed HIV viral load above this value (virological non-responders). Plasma samples, collected before starting therapy and after 1 year of HAART, underwent clonal sequence analysis for HVR-1 region of HCV. Non-synonymous/synonymous substitutions ratio (Ka/Ks), aminoacidic complexity (normalized Shannon entropy) and diversity (p-distance), were considered as parameters of quasispecies heterogeneity. After 1 year of HAART, heterogeneity of HVR-1 quasispecies significantly decreased in virological non-responders, whereas the heterogeneity tended to increase in virological responders. The differences in the evolution were less stringent, when considering immunological response. On the other hand, profound qualitative modifications of HVR-1 quasispecies were observed only in patients with both immunological and virological HAART response.

On the whole, these findings suggest that, in patients undergoing HAART, the extent of HCV variability and the evolution of HVR-1 quasispecies is influenced by the pattern of response to antiretroviral therapy.

Response to Haart and Gb Virus Type C Coinfection in a Cohort of Antiretroviral-Naive HIV-Infected Individuals

The prognostic role of GB virus type C (GBV-C) viraemia in HIV-infected subjects treated with highly active antiretroviral therapy (HAART) is still undefined, The aim of this analysis is to assess the relationship between GBV-C infection and response to antiretroviral therapy among HIV-infected subjects initiating HAART when antiretroviral-naive.

A prospective, observational study of 400 HIV-infected patients with measurements of GBV-C RNA, hepatitis C virus (HCV) antibodies and HCV RNA determined from plasma stored prior to HAART initiation, Time to virological (achieving HIV RNA ≤500 copies/ml) and immunological success (a CD4+ count increase of ≥200cells/μl), and the time to virological relapse (confirmed HIV RNA >500 copies/ml) were assessed by Kaplan-Meier methods and Cox proportional hazard regression model.

Of the subjects, 117 (29.3%) were GBV-C positive and, overall, 351 (87.8%) patients achieved virological success, After controlling for a number of confounders including HCV RNA, GBV-C viraemic patients experienced a significantly lower risk of HIV rebound than those who were GBV-C negative [relative hazard (RH)=0.56, 95% CI: 0.34–0.93, P=0.03], Conversely, the probability of achieving initial virological success or CD4+ count response after HAART did not differ between GBV-C-negative and -positive subjects, These results suggest that GBV-C coinfection may play a role in determining the rate of HIV rebound possibly by competing with HIV replication after HIV load has been successfully suppressed by HAART.

Variability in the Interpretation of Transmitted Genotypic HIV-1 Drug Resistance and Prediction of Virological Outcomes of the Initial Haart by Distinct Systems

High level HIV-1 drug resistance in recently infected treatment-naive individuals correlates with sub-optimal virological responses to highly active antiretroviral therapy (HAART). To determine whether genotypic HIV-1 drug resistance in chronic naive patients, as interpreted by various systems, could predict the virological outcomes of HAART, isolates from patients enrolled in a prospective observational cohort (ICoNA) prior to treatment start were genotyped. Genotypic susceptibility scores (GSS) assigned to the initial HAART regimens using the interpretations of pre-therapy resistance mutations by 13 systems were related to virological outcomes. Of 415 patients, 42 (10%) had at least one major resistance mutation. According to the different interpretations, 1.9–20.5% of patients had some level of resistance to at least one drug in the initial regimen. In multivariable analysis, GSS from two systems significantly predicted the time to virological success: Rega 5.5, for each unit increase in GSS adjusted relative hazard (RH) 1.86 [95% confidence intervals (95% CI): 1.15–3.02] and hivresistanceWeb v3, RH 1.87 (95% CI: 1.00–3.48). With three other systems, GSS showed a trend towards a significant prediction of success: Retrogram 1.6, RH 2.33 (95% CI: 0.98–5.53), Menéndez 2002, RH 2.36 (95% CI: 0.97–5.72) and Stanford hivdb, RH 2.06 (95% CI: 0.94–4.49). Genotypic resistance testing coupled with adequate interpretation in chronic naive patients can usefully identify those at risk of sub-optimal virological response to HAART.

The Management of Hepatitis B Virus/HIV-1 Co-Infected Patients Starting Their First Haart Regimen. Treating Two Infections for the Price of One Drug?

We examined the impact of a lamivudine-containing highly active antiretroviral therapy (HAART) regimen on 164 hepatitis B virus/HIV co-infected individuals starting their first HAART. Lamivudine-treated patients (accounting for 73% of the study population) showed a significantly lower level of alanine aminotransferase over follow-up [–81.1 mU/ml mean difference; 95% confidence intervals (95% CI): –30.3; –131.7, P=0.003] and a significantly reduced risk of liver-related morbidity/mortality [Relative hazard (RH)=0.07; 95% CI: 0.01–0.38, P=0.002] than those starting a lamivudine sparing-regimen.

Absolute TCD4+ counting by a minimalist dual-platform flow cytometric method

The aim of this work was to compare the performance of an absolute TCD4+ counting method based on total WBC gating versus the standard lymphocyte (Ly) gating method, in order to develop a flow cytometric (FCM) minimalist strategy for TCD4+ enumeration.

METHOD

132 routine peripheral blood samples, mainly from HIV infected patients, were labelled with CD3-FITC/CD4-PE/CD45-PECy5 and analyzed by two gating methods: a) standard method based on Ly immunological gating (CD45++SSClow), followed by the determination of CD3+CD4+ percentage and absolute number (# calculation using Ly # from hematological analyser (HA); b) total WBC immunological gate on biparametric scatter CD45/CD4, followed by CD4++SSClow percentage determination and absolute number calculation using WBC absolute number from hematological counter without using the WBC differential. Moreover on 63 samples Ly # based on Ly % from FCM and WBC counting from HA was compared with Ly # from HA.

RESULTS

The TCD4+/microL ranged from 3 to 3277 and the statistical analysis results showed: a) linear regression: r2 = 0.9847; b) Bland & Altman analysis: difference mean = -56.22; agreement range = +95.68 / -208.12; c) the mean of result difference/mean value*100 between two methods was -9.06%; d) comparison between regression line and the boundaries for acceptable residual values based on regressed confidence limits found by A. Kunkl et al showed regression line within boundaries near the upper limits. The Ly/microL count ranged from 635 to 8752. The statistical analysis results showed: a) linear regression: r2 = 0.9764; b) Bland & Altman analysis: difference mean = -362.93; agreement range = +134.51 / -860.37; c) the mean of result difference/mean value*100 between two methods was -16.12%.

CONCLUSIONS

Our results suggest a fair agreement between the two gating methods, but the one based on total WBC gate gives TCD4+/microL counts systematically higher than the standard method. This finding can be attributed to a systematic lower estimation of Ly% by HA.

Rhodium/iridium-titanium azaheterometallocubanes

Treatment of [[Ti(eta5-C5Me5)(mu-NH)]3(mu3-N)] (1) with the diolefin complexes [[MCl(cod)]2] (M = Rh, Ir; cod = 1,5-cyclooctadiene) in toluene afforded the ionic complexes [M-(cod)(mu3-NH)3Ti3(eta5-C5Me5)3(mu3-N)]Cl [M = Rh (2), Ir (3)]. Reaction of complexes 2 and 3 with [Ag(BPh4)] in dichloromethane leads to anion metathesis and formation of the analogous ionic derivatives [M(cod)(mu3-NH)3Ti3-(eta5-C5Me5)3(mu3-N)][BPh4] [M = Rh (4), Ir (5)]. An X-ray crystal structure determination for 5 reveals a cube-type core [IrTi3N4] for the cationic fragment, in which 1 coordinates in a tripodal fashion to the iridium atom. Reaction of the diolefin complexes [[MCl(cod))2] (M = Rh, Ir) and [[RhCl(C2H4)2]2] with the lithium derivative [[Li(mu3-NH)2(mu3-N)-Ti3(eta5-C5Me5)3(mu3-N)]2] x C7H8 (6 C7H8) in toluene gave the neutral cube-type complexes [M(cod)(mu-NH)2(mu3-N)Ti3-(eta5-C5Me5)3(mu3-N)] [M = Rh (7), Ir (8)] and [Rh(C2H4)2(mu3-NH)2(mu3-N)Ti3(eta5-C5Me5)3(mu3-N)] (9), respectively. Density functional theory calculations have been carried out on the ionic and neutral azaheterometallocubane complexes to understand their electronic structures.

Titanium alkali metal nitrido complexes

Treatment of [(Ti(eta5-C5Me5)(mu-NH))3(mu3-N)] with alkali metal bis(trimethylsilyl)amido reagents in toluene afforded the complexes [M(mu3-N)(mu3-NH)2[Ti3(mu5-C5Me5)3(mu3-N)]]2 (M = Li (2), Na, (3), K (4)). The molecular structures of 2 and 3 have been determined by X-ray crystallographic studies and show two azaheterometallocubane cores [MTi3N4] linked by metal-nitrogen bonds. Reaction of the lithium derivative 2 with chlorotrimethylsilane or trimethyltin chloride in toluene gave the incomplete cube nitrido complexes [Ti3(eta5-C5Me5)3(mu-NH)2(mu-NMMe3)(mu3-N)] (M = Si (5), Sn (6)). A similar reaction with indium(I) or thallium(I) chlorides yielded cube-type derivatives [M(mu3-N)(mu3-NH)2[Ti(eta5-C5Me5)3(mu3-N)] (M=In (7), Tl (8)).

[Fetal drug addiction as a consequence of maternal cocaine free base abuse during pregnancy]

BACKGROUND

Fetal drug addiction is a serious public health problem. In the United States 10 to 15% of children have been exposed "in utero" to cocaine. In a Chilean public health service, more than 200 offspring of cocaine free base abuser have been detected.

AIM

To analyze the clinical and social features of 100 children exposed to cocaine free base during fetal development.

PATIENTS AND METHODS

Clinical features of children born from cocaine free base consume mothers were described at birth. During subsequent follow up, growth and development, disease episodes, developmental alterations and social situation were recorded. Data was compared with other newborns from the same health service.

RESULTS

Compared to their normal counterparts, exposed children has a lower birth weight, the frequency of premature babies was thrice higher, and small-for-gestational age children were four times more common. There was also a higher prevalence of cardiac malformations, seizures and apnea. Hospital admissions were more frequent, prolonged and required more complex facilities. During follow up, undernutrition and stunting were more prevalent. Psychomotor retardation was present in 67% of children and behavioral disturbances in 93%. Most of these children are governmental protection.

CONCLUSIONS

Strategies to prevent drug abuse during pregnancy and its devastating medical and social consequences should be urgently developed (Rev Méd Chile 2000; 128: 1093-1100).

Cytologic and biomolecular diagnosis of polyomavirus infection in urine specimens of HIV-positive patients

OBJECTIVE

To evaluate the frequency of human polyomavirus reactivation in urine specimens from HIV-positive patients; compare the sensitivity of cytology, immunohistochemistry and molecular biology; differentiate viral genotypes; and correlate the results with urinary cytologic abnormalities.

STUDY DESIGN

Urine specimens from 78 unselected HIV-positive patients were evaluated by means of cytology, immunohistochemistry and nested polymerase chain reaction (n-PCR) to evaluate the presence of polyomaviruses. Restriction fragment length polymorphism (RFLP) was carried out in positive cases in order to differentiate BK virus (BKV) from JC virus (JCV). CD4 cells and serum creatinine levels were evaluated as indices of immune status and renal function, respectively, whereas the presence of red blood cells was used as an index of urogenital damage.

RESULTS

Cytologic evidence of polyomavirus infection was found in 17 samples and immunohistochemically confirmed in 9; another 6 cytologically negative cases were detected by means of immunohistochemistry. In all cases, only one or two cells showed typical viral inclusions or positive staining. n-PCR identified 44 positive samples, thus confirming all of the cytologically and immunohistochemically positive cases and detecting polyomavirus genome in a further 21. RFLP detected 39 JCV, 1 BKV and 4 JCV-BKV infections. No correlation was found between the presence or type of polyomavirus and immune status, but red blood cells were found more frequently in the positive than in the negative samples. Serum creatinine levels fell within the normal range in all cases.

CONCLUSION

Molecular biology is the most sensitive tool for detecting polyomavirus urinary infection in HIV-positive patients and the only reliable method of differentiating JCV and BKV viral genotypes.

Ammonolysis of mono(pentamethylcyclopentadienyl) titanium(IV) derivatives

Ammonolyses of mono(pentamethylcyclopentadienyl) titanium(IV) derivatives [Ti(eta5-C5Me5)X3] (X = NMe2, Me, Cl) have been carried out in solution to give polynuclear nitrido complexes. Reaction of the tris(dimethylamido) derivative [Ti(eta5-C5Me5)(NMe2)3] with excess of ammonia at 80-100 degrees C gives the cubane complex [[Ti(eta5-C5Me5)]4(mu3-N)4] (1). Treatment of the trimethyl derivative [Ti(eta5-C5Me5)Me3] with NH3 at room temperature leads to the trinuclear imido-nitrido complex [[Ti(eta/5-CsMes)(mu-NH)]3(mu3-N)] (2) via the intermediate [[Ti(eta5-C5Me5)Me]2(mu-NH)2] (3). The analogous reaction of [Ti(eta5-C5Me5)Me3] with 2,4,6-trimethylaniline (ArNH2) gives the dinuclear imido complex [[Ti(eta5-C5Me5)Me])2(mu-NAr)2] (4) which reacts with ammonia to afford [[Ti(eta5-C5Me5)(NH2)]2(mu-NAr)2] (5). Complex 2 has been used, by treatments with the tris(dimethylamido) derivatives [Ti(eta5-C5H5-nRn)(NMe2)3], as precursor of the cubane nitrido systems [[Ti4(eta5-C5Me5)3(eta5-C5H5-nRn)](mu3-N)4] [R = Me n = 5 (1), R = H n = 0 (6), R = SiMe3 n = 1 (7), R = Me n = 1 (8)] via dimethylamine elimination. Reaction of [Ti(eta5-C5Me5)Cl3] or [Ti(eta5-C5Me5)(NMe2)Cl2] with excess of ammonia at room temperature gives the dinuclear complex [[Ti2(eta5-C5Me5)2Cl3(NH3)](mu-N)] (9) where an intramolecular hydrogen bonding and a nonlineal nitrido ligand bridge the "Ti(eta5-C5Me5)Cl(NH3)" and "Ti(eta5-C5Me5)Cl2" moieties. The molecular structures of [[Ti(eta5-C5Me5)Me]2 (mu-NAr)2] (4) and [[Ti2(eta5-C5Me5)2Cl3(NH3)](mu-N)] (9) have been determined by X-ray crystallographic studies. Density functional theory calculations also have been conducted on complex 9 to confirm the existence of an intramolecular N-H...Cl hydrogen bond and to evaluate different aspects of its molecular disposition.

Construction of Heterometallic Cubanes

Incorporation of M(CO)(3) fragments by trinuclear Ti complexes [{Ti(3)Cp<![IGNORE[$\curr {\brol{{\stern}}{3}}$]]>(µ(3)-CR)}(µ-O)(3)] and [{Ti(3)Cp<![IGNORE[$\curr {\brol{{\stern}}{3}}$]]>(µ(3)-N)}(µ-NH)(3)] (Cp*=eta(5)-C(5)Me(5)) leads to the formation of an unprecedented class of heterometallic clusters with cubane structure [e.g., Eq. (a)]. Density functional calculations on these complexes indicate the existence of electron delocalization in the Ti(3)M cores (M=Cr, Mo, W).

An endosperm-specific DOF protein from barley, highly conserved in wheat, binds to and activates transcription from the prolamin-box of a native B-hordein promoter in barley endosperm

A cDNA encoding a DNA-binding protein of the DOF class of transcription factors was isolated from a barley endosperm library. The deduced amino acid sequence for the corresponding protein is 94% identical through the DOF domain to the prolamin-box (P-box) binding factor PBF from maize. The gene encoding the barley PBF (BPBF) maps to chromosome 7H, and its expression is restricted to the endosperm where it precedes that of the hordein genes. The BPBF expressed in bacteria as a GST-fusion binds a P-box 5'-TGTAAAG-3' containing oligonucleotide derived from the promoter region of an Hor2 gene. Binding was prevented when the P-box motif was mutated to 5'-TGTAgAc-3'. A P-box binding activity, present in barley and wheat endosperm nuclei, interacted similarly to BPBF with this synthetic oligonucleotide, and the binding was abolished by 1,10-phenanthroline. Transient expression experiments in developing barley endosperms demonstrate that BPBF transactivates transcription from the P-box element of a native Hor2 promoter and that direct binding of BPBF to its target site is essential for transactivation since mutations in the DOF DNA-binding domain or in the P-box motif of this promoter abolished both binding and transactivation. Evidence was also obtained for the presence in wheat of a Pbf homologue having similar DNA-binding properties to that of BPBF. These results strongly implicate this endosperm-specific DOF protein from barley as an important activator of hordein gene expression and suggest the evolutionary conservation of the Pbf gene function among small grain cereals.

Differential expression of pathogen-responsive genes encoding two types of glycine-rich proteins in barley

Gene-specific probes (3' ends of cDNAs) were obtained from barley cDNAs encoding two types of glycine-rich proteins: HvGRP2, characterized by a cytokeratin-like and a cysteine-rich domain, and HvGRP3, whose main feature was an RNA-binding domain. Expression of genes Hvgrp2 and Hvgrp3, which are present at one (or two) copies per haploid genome, was ubiquitous and gene Hvgrp3 was under light/darkness modulation. Cold treatment increased Hvgrp2 and Hvgrp3 mRNA levels. Methyl jasmonate (10 microM) switched off the two genes. Expression of Hvgrp2, but not that of Hvgrp3, was induced by ethylene treatment (100 ppm). Fungal pathogens Erysiphe graminis and Rhynchosporium secalis increased the mRNAs levels of the two genes, both in compatible and in incompatible interactions, while bacterial pathogens did not.

Diversification of C-function activity in maize flower development

The Arabidopsis gene AGAMOUS is required for male and female reproductive organ development and for floral determinacy. Reverse genetics allowed the isolation of a transposon-induced mutation in ZAG1, the maize homolog of AGAMOUS. ZAG1 mutants exhibited a loss of determinacy, but the identity of reproductive organs was largely unaffected. This suggested a redundancy in maize sex organ specification that led to the identification and cloning of a second AGAMOUS homolog, ZMM2, that has a pattern of expression distinct from that of ZAG1. C-function organ identity in maize (as defined by the A, B, C model of floral organ development) may therefore be orchestrated by two closely related genes, ZAG1 and ZMM2, with overlapping but nonidentical activities.