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BACKGROUND: Intraneural injection of local anaesthetic agents carries a risk of neurological complications. Early detection of intraneural needle-tip position is very important in the initial phase of injection. Ultrasound (US) characteristics for real-time detection of intraneural injections have been described, but only for relatively large volumes (5-40 ml). This study assesses the reliability of various US criteria to detect early low volume (0.5 ml) intraneural injections. Intraneural deposition of an injected dye was confirmed by cryomicrotomy. METHODS: In nine unembalmed human cadavers, 0.5 ml methylene blue was injected intraneurally into the supraclavicular brachial plexus and subgluteal sciatic nerve on both sides. The sites of injection were subsequently removed en bloc. Consecutive cryomicrotomy cross-sections with a 50 µm interval were obtained to assess intraneural presence of the injectate. Two independent experts separately reviewed US video clips of the injections and scored each US criterion. RESULTS: Of the 36 injections, cryomicrotome cross-sections showed intraneural staining in 33 and extraneural staining in three. The best US criterion was expansion of the nerve cross-sectional surface area together with a change in echogenicity. It was observed in 35 injections, including two false positives. There was one true negative. Test precision was 94% [95% confidence interval (CI), 87-100%]. The mean increase in surface area was 8.7% (95% CI, 5.6-11.9). CONCLUSIONS: Reliable detection of early low-volume intraneural injection using US is possible using expansion of the cross-sectional surface area of the nerve together with a change in echogenicity as markers.
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Plexo Braquial/diagnóstico por imagen , Bloqueo Nervioso/métodos , Nervio Ciático/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inyecciones , Masculino , UltrasonografíaRESUMEN
Despite the progress made in HIV treatment and prevention, HIV remains a major cause of adolescent morbidity and mortality in sub-Saharan Africa. As perinatally infected children increasingly survive into adulthood, the quality of life and mental health of this population has increased in importance. This review provides a synthesis of the prevalence of mental health problems in this population and explores associated factors. A systematic database search (Medline, PsycINFO, Scopus) with an additional hand search was conducted. Peer-reviewed studies on adolescents (aged 10-19), published between 2008 and 2019, assessing mental health symptoms or psychiatric disorders, either by standardized questionnaires or by diagnostic interviews, were included. The search identified 1461 articles, of which 301 were eligible for full-text analysis. Fourteen of these, concerning HIV-positive adolescents, met the inclusion criteria and were critically appraised. Mental health problems were highly prevalent among this group, with around 25% scoring positive for any psychiatric disorder and 30-50% showing emotional or behavioral difficulties or significant psychological distress. Associated factors found by regression analysis were older age, not being in school, impaired family functioning, HIV-related stigma and bullying, and poverty. Social support and parental competence were protective factors. Mental health problems among HIV-positive adolescents are highly prevalent and should be addressed as part of regular HIV care.
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BACKGROUND AND OBJECTIVES: The sciatic nerve block represents one of the more difficult ultrasound-guided nerve blocks. Easy and reliable internal ultrasound landmarks would be helpful for localization of the sciatic nerve. Earlier, during ultrasound-guided posterior approaches to the infragluteal sciatic nerve, the authors recognized a hyperechoic structure at the medial border of the long head of biceps femoris muscle (BFL). The present study was performed to determine whether this is a potential internal landmark to identify the infragluteal sciatic nerve. METHODS: The depth and the thickness of this hyperechoic structure, its relationship with the sciatic nerve and the ultrasound visibility of both were recorded in the proximal upper leg of 21 adult volunteers using a linear ultrasound probe in the range of 7-13 MHz. The findings were verified by an anatomical study in two cadavers. RESULTS: The hyperechoic structure at the medial border of the BFL extended in a dorsoventral direction between 1.4+/-0.6 cm (mean+/-SD) and 2.8+/-0.8 cm deep from the surface, with a width of 2.2+/-0.9 mm. Between 2.6+/-0.9 and 10.0+/-1.5 cm distal to the subgluteal fold, the sciatic nerve was consistently identified directly at the ventral end of the hyperechoic structure in all volunteers. The anatomical study revealed that this hyperechoic structure corresponds to tendinous fibres inside and at the medial border of the BFL. CONCLUSION: The hyperechoic BFL tendon might be a reliable soft tissue landmark for ultrasound localization of the infragluteal sciatic nerve.
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Músculo Esquelético/diagnóstico por imagen , Bloqueo Nervioso/métodos , Nervio Ciático/diagnóstico por imagen , Tendones/diagnóstico por imagen , Adulto , Cadáver , Femenino , Humanos , Masculino , Microtomía , Persona de Mediana Edad , Muslo/anatomía & histología , Muslo/diagnóstico por imagen , UltrasonografíaRESUMEN
The definition of sciatica is restricted to the pattern and localization of pain, although much emphasis is given to root compression as causative factor. Other sources of similar pain patterns are generally neglected. Despite absence of obligatory neurological signs in radicular syndromes, a number of patients are subjected to extensive, but redundant screenings. In this report, three patients are presented with presumed radicular pain syndromes, whose symptoms finally could be linked to the sacroiliac (SI) joint either via CT and MRI scans or via pain relief by intra-articular injection with local anaesthetics. Possible mechanisms of SI joint-related pain and difficulties in diagnostic specificity of signs and symptoms are discussed.
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Articulación Sacroiliaca , Ciática/diagnóstico , Adulto , Anestésicos Locales/uso terapéutico , Diagnóstico Diferencial , Femenino , Humanos , Inyecciones Intraarticulares , Desplazamiento del Disco Intervertebral/diagnóstico , Vértebras Lumbares , Imagen por Resonancia Magnética , Persona de Mediana Edad , Dimensión del Dolor/métodos , Dolor Referido/diagnóstico , Ciática/tratamiento farmacológico , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Current resting state imaging findings support suggestions that the neural signature of depression and therefore also its therapy should be conceptualized as a network disorder rather than a dysfunction of specific brain regions. In this study, we compared neural connectivity of adolescent patients with depression (PAT) and matched healthy controls (HC) and analysed pre-to-post changes of seed-based network connectivities in PAT after participation in a cognitive behavioral group psychotherapy (CBT). METHODS: 38 adolescents (30 female; 19 patients; 13-18 years) underwent an eyes-closed resting-state scan. PAT were scanned before (pre) and after (post) five sessions of CBT. Resting-state functional connectivity was analysed in a seed-based approach for right-sided amygdala and subgenual anterior cingulate cortex (sgACC). Symptom severity was assessed using the Beck Depression Inventory Revision (BDI-II). RESULTS: Prior to group CBT, between groups amygdala and sgACC connectivity with regions of the default mode network was stronger in the patients group relative to controls. Within the PAT group, a similar pattern significantly decreased after successful CBT. Conversely, seed-based connectivity with affective regions and regions processing cognition and salient stimuli was stronger in HC relative to PAT before CBT. Within the PAT group, a similar pattern changed with CBT. Changes in connectivity correlated with the significant pre-to-post symptom improvement, and pre-treatment amygdala connectivity predicted treatment response in depressed adolescents. LIMITATIONS: Sample size and missing long-term follow-up limit the interpretability. CONCLUSIONS: Successful group psychotherapy of depression in adolescents involved connectivity changes in resting state networks to that of healthy controls.
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Terapia Cognitivo-Conductual/métodos , Trastorno Depresivo/patología , Trastorno Depresivo/terapia , Psicoterapia de Grupo/métodos , Descanso/fisiología , Adolescente , Amígdala del Cerebelo/fisiopatología , Mapeo Encefálico , Depresión , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética/métodos , Escalas de Valoración PsiquiátricaRESUMEN
The presence of both pro-opiomelanocortin-derived peptides and melanocortin (MC) receptors in nociception-associated areas in the spinal cord suggests that, at the spinal level, the MC system might be involved in nociceptive transmission. In the present study, we demonstrate that a chronic constriction injury (CCI) to the rat sciatic nerve, a lesion that produces neuropathic pain, results in changes in the spinal cord MC system, as shown by an increased binding of (125)I-NDP-MSH to the dorsal horn. Furthermore, we investigated whether intrathecal administration (in the cisterna magna) of selective MC receptor ligands can affect the mechanical and cold allodynia associated with the CCI. Mechanical and cold allodynia were assessed by measuring withdrawal responses of the affected limb to von Frey filaments and withdrawal latencies upon immersion in a 4.5 degrees C water bath, respectively. We show that treatment with the MC receptor antagonist SHU9119 has a profound anti-allodynic effect, suggesting that the endogenous MC system has a tonic effect on nociception. In contrast, administration of the MC4 receptor agonists MTII and d-Tyr-MTII primarily increases the sensitivity to mechanical and cold stimulation. No antinociceptive action was observed after administration of the selective MC3 receptor agonist Nle-gamma-MSH. Together, our data suggest that the spinal cord MC system is involved in neuropathic pain and that the effects of MC receptor ligands on the responses to painful stimuli are exerted through the MC4 receptor. In conclusion, antagonism of the spinal melanocortin system might provide a new approach in the treatment of neuropathic pain.
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Frío , Hiperalgesia/metabolismo , Receptores de Corticotropina/antagonistas & inhibidores , Neuropatía Ciática/metabolismo , alfa-MSH/análogos & derivados , Animales , Autorradiografía , Constricción , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inyecciones Espinales , Ligandos , Masculino , Hormonas Estimuladoras de los Melanocitos/administración & dosificación , Oligopéptidos/farmacología , Dimensión del Dolor/efectos de los fármacos , Estimulación Física , Ratas , Ratas Wistar , Tiempo de Reacción/efectos de los fármacos , Receptor de Melanocortina Tipo 3 , Receptor de Melanocortina Tipo 4 , Receptores de Corticotropina/administración & dosificación , Receptores de Corticotropina/agonistas , Receptores de Corticotropina/metabolismo , Receptores de Melanocortina , Nervio Ciático/fisiología , Nervio Ciático/cirugía , Umbral Sensorial/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismoRESUMEN
BACKGROUND: While major effort has been put in investigating neural correlates of depression and its treatment in adults, less is known about the effects of psychotherapy in adolescents. Given the concordance of the ventral striatum, amygdala, hippocampus and the subgenual anterior cingulate cortex (sgACC) as correlates of depression and their involvement in reward processing, we used functional magnetic resonance imaging (fMRI) during performance of a monetary reward task in an intervention versus waitlist-control design to investigate the clinical and neural effects of cognitive behavioral group therapy (CBT-G). METHODS: 22 medication naïve adolescents with major depressive disorder were scanned before and after five sessions of CBT-G (PAT-I), or before and after five weeks of waiting (PAT-W). Changes in symptom scales were analyzed along with neural activation changes within the amygdala, hippocampus, sgACC and ventral striatum regions of interest (ROI). RESULTS: Psychometric assessments and ROI activation remained unchanged in PAT-W. In PAT-I, significant reduction in clinical symptoms accompanied significant changes in brain activation within the left amygdala, left hippocampus and bilateral sgACC. In line with previous findings in adults, pre-to-post-activation changes in the bilateral sgACC correlated with pre-to-post and pre-to-follow-up symptom improvement, and individual expressions of sgACC activation before treatment were related to pre-to-follow-up therapeutic success. LIMITATIONS: Future studies should include larger sample sizes. CONCLUSIONS: Successful group psychotherapy of depression in adolescents was related to signal changes in brain regions previously demonstrated to be reliably linked with successful, particularly pharmacological treatment in adults.
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Amígdala del Cerebelo/patología , Terapia Cognitivo-Conductual/métodos , Trastorno Depresivo Mayor/patología , Trastorno Depresivo Mayor/terapia , Adolescente , Encéfalo/fisiopatología , Mapeo Encefálico , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Resultado del TratamientoRESUMEN
PIP: HIV-1 and HIV-2 both cause AIDS in humans. Simian immunodeficiency viruses (SIV) are non-human primate lentiviruses and the closest known relatives of the HIVs. They closely parallel HIVs in genomic organization and biologic properties. The authors discuss the known HIVs and SIVs of African origin and describe the variability which exists in the different groups. HIV-1 and HIV-2 share approximately 55-60% amino-acid homology in gag and pol, the genes most highly conserved among related retroviruses. HIV-1 is spread widely throughout the world, while HIV-2 infection appears to be concentrated in West Africa. Rare cases of HIV-2 infection have, however, been identified in Europe and America, usually in individuals connected with West Africa. The authors discuss viral genetic variation and variation of biological phenotype, and findings on HIV-1 and HIV-2 from Zaire, Uganda, Cameroon, Tanzania, Ethiopia, Congo, Ghana, the Gambia, Guinea-Bissau, and Cote d'Ivoire.^ieng
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Variación Genética , VIH-1/genética , VIH-2/genética , Virus de la Inmunodeficiencia de los Simios/genética , Síndrome de Inmunodeficiencia Adquirida/microbiología , África , Animales , Humanos , Primates , Síndrome de Inmunodeficiencia Adquirida del Simio/microbiologíaRESUMEN
OBJECTIVES: To determine the sensitivity of HIV-antibody assays for detecting low levels of HIV antibody using seroconversion and other panels containing plasma of varying titres. METHODS: Eight HIV-antibody assays, available under the World Health Organization bulk-procurement agreement, were evaluated on sets of sequential plasma samples derived from 11 individuals who had recently become HIV-infected (seroconversion panels). In addition, two non-seroconversion panels, consisting of low performance (titre) and mixed titre samples were used to further define the sensitivity of the assays. The eight assays included two rapid tests, one simple test, and five enzyme-linked immunosorbent assays (ELISA). RESULTS: On average, the eight assays detected antibody 0.5-4.8 days later than the reference test (Abbott HIV-1/HIV-2 3rd generation ELISA); these differences were statistically significant for six of the eight tests. All tests performed well on the low performance and mixed titre panels. All eight assays also had comparable sensitivity to that of the reference test on a large panel of known positive plasma. The additional risk of missing an infectious unit of blood during seroconversion by using the least sensitive rather than the reference test was estimated to be 1 in 7600 and 1 in 76 million at annual HIV incidence rates of 1 and 0.0001%, respectively. The cost of eliminating this additional risk by using the reference test is between US$ 15,150 and 151 million per unit detected at the above incidence rates. CONCLUSIONS: Although there are differences in sensitivity between the assays when used to test blood from individuals during the course of seroconversion, the differences are small, and all eight tests are appropriate for use as screening tests.
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Serodiagnóstico del SIDA/métodos , Anticuerpos Anti-VIH/sangre , Seropositividad para VIH/inmunología , Serodiagnóstico del SIDA/normas , Serodiagnóstico del SIDA/estadística & datos numéricos , Pruebas de Aglutinación/métodos , Pruebas de Aglutinación/normas , Pruebas de Aglutinación/estadística & datos numéricos , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/normas , Ensayo de Inmunoadsorción Enzimática/estadística & datos numéricos , Estudios de Evaluación como Asunto , Reacciones Falso Negativas , Seropositividad para VIH/diagnóstico , Humanos , Immunoblotting/métodos , Immunoblotting/normas , Immunoblotting/estadística & datos numéricos , Estándares de Referencia , Sensibilidad y Especificidad , Factores de Tiempo , Organización Mundial de la SaludRESUMEN
OBJECTIVE: To characterize near-full-length genomes of two HIV-1 subtype H strains. To extend sequence data to include full env and gag, and analyse and redefine, previously documented subtype H strains. DESIGN: Near-full-length genomes of HIV-1 env subtype H strains VI991 and VI997 were amplified, cloned, sequenced, phylogenetically analysed and compared with a panel of 23 HIV-1 group M reference isolates. The mosaic nature of previously published subtype H strains VI557 and CA13 was reanalysed. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMC) from individuals harbouring strains VI991 and VI997 were co-cultivated with PHA stimulated donor PBMC. Near-full-length genomes of VI991 and VI997, and gag and env genes of CA13 and VI557, were amplified by polymerase chain reaction, cloned and sequenced. Intersubtype recombination analyses were performed by similarity plot, bootscanning and phylogenetic analysis. RESULTS: Near-full-length clones of HIV-1 VI991 and VI997 are representative of subtype H. They form a phylogenetic cluster with the only previously described subtype H representative HIV-1 90CF056.1, regardless of the genome region analysed. VI557 is redefined as a gag and env subtype H mosaic virus containing unclassified fragments. CA13 is a complex intersubtype recombinant between subtypes A, H and unclassified strains CONCLUSION: Near-full-length genome analysis identified HIV-1 VI991 and VI997 as two new subtype H representatives. These reagents will allow defining and classifying non-recombinant as well as recombinant HIV-1, eventually helping to solve the puzzle of HIV-1 subtypes.
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Genes env , Genes gag , Genoma Viral , Infecciones por VIH/virología , VIH-1/genética , Recombinación Genética , Secuencia de Bases , ADN Viral , Infecciones por VIH/sangre , VIH-1/clasificación , Humanos , Datos de Secuencia Molecular , Filogenia , Estándares de ReferenciaRESUMEN
OBJECTIVE: A comparative study of the replication kinetics of different HIV-1 variants (including SIV(cpz)) was undertaken to determine which viral characteristics were associated with sustained plasma viraemia in chimpanzees. DESIGN: Plasma samples from chimpanzees infected with six different HIV-1 clade B isolates were compared with plasma samples from SIV(cpz-ant)-infected chimpanzees. METHODS: A pan-clade quantitative competitive reverse transcriptase-polymerase chain reaction assay was developed based on conserved primer sequences recognizing M, N and O human lentiviruses as well as different SIV(cpz) isolates. RESULTS: Important differences between early kinetics in the human lentivirus isolates as well as compared with the chimpanzee isolate SIV(cpz-ant) were observed. R5-dependent non-syncytium-inducing (NSI) isolates (5016, Ba-L, SIV(cpz)) were found to have relatively higher viral loads than the syncytium-inducing (SI), X4-dependent primary (SF2), T cell-adapted (IIIB) or X4/R5 (Han2, DH12) SI primary isolates. CONCLUSION: Infection of chimpanzees with NSI R5-utilizing isolates correlated with persistent viraemia (approximately 10(4) RNA equivalents/ml) in contrast to transient viraemia observed after infection with SI X4-utilizing isolates.
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Enfermedades del Simio Antropoideo/virología , Infecciones por VIH/virología , VIH-1/fisiología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/fisiología , Carga Viral , Animales , Células Gigantes/fisiología , VIH-1/clasificación , Humanos , Pan troglodytes , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Virus de la Inmunodeficiencia de los Simios/clasificaciónRESUMEN
An inhibition enzyme immunoassay (IEIA), using a human monoclonal antibody (K14) reactive with gp41 of HIV-1, was evaluated for its applicability to the serology of HIV-1 infections. Using panels of serum samples from seronegative and confirmed HIV-1-seropositive individuals, it was shown that all the HIV-1-positive samples in a panel from The Netherlands and 97% of the HIV-1-positive samples from Tanzania were identified by this IEIA. Six per cent of the IEIA-positive samples from Tanzania could not be confirmed in other assays. Testing of serial dilutions of serum samples from African individuals with confirmed HIV-1, HIV-2 or HIV(ANI70) infections in the K14 IEIA, indicated that a HIV-1-specific assay based on this principle may be developed.
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Anticuerpos Monoclonales/inmunología , Proteína gp41 de Envoltorio del VIH/inmunología , Infecciones por VIH/diagnóstico , VIH-1/inmunología , Técnicas para Inmunoenzimas , Estudios de Evaluación como Asunto , HumanosRESUMEN
OBJECTIVE: To estimate the relative substitution rate of the individual positions in an alignment of HIV-1 env sequences coding for areas V3, V4, V5, and the beginning of gp41, and to study phylogenetic relationships between HIV-1 strains taking into account these substitution rate estimates. DESIGN: Phylogenetic comparison of 145 HIV-1 strains classified in HIV-1 group M, subtypes A-H and isolated from patients of 24 different geographical origins. METHODS: A new method recently developed for measuring the substitution rates of the individual nucleotides in a sequence alignment was applied to an alignment of env gene sequences. From the resulting substitution rate distribution, an equation was derived that describes the relationship between dissimilarity and evolutionary distance better than equations previously available. Phylogenetic trees were then constructed from matrices of distances computed using this new equation. RESULTS: 'Substitution rate calibration' offers detailed information on the relative substitution rate or variability of the nucleotides in the env gene. A large phylogenetic tree of 145 env gene sequences constructed by neighbour-joining and taking into account the substitution rate spectrum for this gene, clearly shows the existence of the eight subtypes A-H, all supported at a bootstrap level of 90% or higher. Intersubtype distances were between 0.25 and 0.38, which is considerably higher than those found in trees not considering differences in substitution rates among different alignment positions. CONCLUSIONS: Evolutionary distances are seriously underestimated when individual substitution rates are not considered in the estimation evolutionary distances. Furthermore, due to the more accurate estimation of evolutionary distances, naturally occurring HIV-1 intersubtype recombinants could be recognized more easily.
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Genes env , Seropositividad para VIH/virología , VIH-1/genética , Secuencia de Bases , ADN Viral , VIH-1/clasificación , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Mutagénesis , Nucleótidos , FilogeniaRESUMEN
OBJECTIVE: To compare the performance of V3-loop peptide enzyme immunoassay (PEIA) methodologies from four different laboratories for subtyping HIV-1, and to determine the causes for the lack of correlation between V3-loop PEIA serotyping and subtyping by sequencing. MATERIALS AND METHODS: Synthetic peptides derived from the amino-acid consensus sequences of the V3-loop of group M strains representing genetic subtypes A-F as well as reference strains were evaluated in PEIA by four different laboratories for their ability to accurately determine the subtype in a panel of 85 sera obtained from persons infected with known HIV-1 subtypes (28 subtype A, 34 subtype B, four subtype C, 10 subtype D, seven subtype F, one each of subtype H and G). Furthermore, the V3 loop of the corresponding virus was compared with the V3 loop of the peptides used in PEIA. RESULTS: The correlation between HIV-1 subtyping by sequencing and V3-loop PEIA from the different laboratories varied considerably for the different HIV-1 subtypes: subtype A (46-68%), B (38-85%), C (75-100%), D (29-50%), and F (17-57%). A 70% agreement between PEIA and sequencing subtypes was observed for samples with the concordant presence of the same octameric sequences in the V3 loop of the virus and the V3 loop of the peptide used in PEIA; however, only 42% of specimens with different V3-loop octameric viral and peptide sequences yielded concordant results in V3-loop serotyping and genetic subtyping. CONCLUSION: Our results indicate that V3-loop PEIA methodologies used in different laboratories correlate poorly with genetic subtyping, and that their accuracy to predict HIV-1 subtypes in sera of Belgian individuals infected with different HIV-1 subtypes (A, B, C, D, F, G and H) vary considerably. The poor correlation between serotyping and genetic subtyping was partly due to the simultaneous occurrence of subtype-specific octameric sequences at the tip of the V3 loop of viruses belonging to different genetic subtypes.
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Genes env , Proteína gp120 de Envoltorio del VIH/clasificación , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/virología , VIH-1/clasificación , Técnicas para Inmunoenzimas , Fragmentos de Péptidos/clasificación , Fragmentos de Péptidos/genética , Secuencia de Aminoácidos , Anticuerpos Anti-VIH/sangre , Proteína gp120 de Envoltorio del VIH/inmunología , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/inmunología , SerotipificaciónRESUMEN
OBJECTIVE: To study the requirements for HIV transfer between dendritic cells (DC) and CD4 T cells, using an in vitro model, combined with flow cytometry. METHODS: Immature DC and macrophages (MA) were generated from monocytes. After infection, DC or MA were cultured alone or with purified CD4 T cells. Intracellular HIV was measured, using (1) the monocyte (MO)-tropic AD8 HIV, endowed with enhanced green fluorescent protein (EGFP); and (2) intracellular staining of laboratory HIV strains and clones from primary isolates. RESULTS: (1) Clone AD8-EGFP infected DC and MA with equal efficiency, but the virus was preferentially transferred from DC to autologous T cells. (2) DC were more productively infected with R5/NSI, as compared to X4/SI, HIV, but both HIV phenotypes were easily transmitted to autologous T4 cells. (3) HIV-infected DC transferred the virus to T cells across a semi-permeable membrane, if the T cells were in contact with non-infected DC. (4) Co-culture of T cells with autologous non-infected DC induced T-cell activation. HIV-infected DC selectively increased HLA-DR on T cells and HLA-DR (+) T cells were preferential targets for HIV transfer. (5) Resting Ba-L-infected CD4 T cells were able to transmit the virus 'inversely' to co-cultured DC. CONCLUSION: HIV transfer between monocyte-derived dendritic cells and autologous CD4 T cells was directly demonstrated using flow cytometry. The transfer proceeded in both directions, depended on cellular contact and was associated with partial T-cell activation. This model, representing relevant in vivo targets of HIV, is useful to further investigate interactions between HIV, DC and T cells, without the need for primary ex vivo DC.
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Células Dendríticas/virología , VIH/crecimiento & desarrollo , Linfocitos T/virología , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/virología , Comunicación Celular , Células Cultivadas , Células Dendríticas/citología , Variación Genética , VIH/genética , Antígenos HLA-DR , Humanos , Activación de Linfocitos , Macrófagos/citología , Macrófagos/virología , Modelos Biológicos , Monocitos/citología , Monocitos/virología , Linfocitos T/citologíaRESUMEN
OBJECTIVE: To study the spread of antibodies to V3 loop peptides of two chimpanzee lentiviruses and the divergent HIV-1ANT-70 isolate (group O) in human sera from different geographic regions, and to compare this with reactions to peptides from known North American (subtype B) and Zaïrean (subtype D) strains. METHODS: A total 2495 HIV-1-antibody-positive sera from nine countries were tested by enzyme-linked immunosorbent assay for antibodies to the V3 loop of 10 HIV/SIV isolates (including MN, SF2, HXB2, RF, MAL, ELI, Z6 and ANT-70 for HIV-1, and cpz-gab and cpz-ant for SIV). RESULTS: In each country, the highest prevalences were observed against the MN peptide (58.8-91.7%). Seroreactivity to other peptides from subtype B were generally lower. Prevalences of antibodies to V3 peptides derived from Zaïrean strains belonging to subtype D were generally lower than to subtype B. Relative high prevalences of sera reactive with the SIVcpz-gab V3 peptide were observed. The lowest rates were seen in Brazil (4.2%) and Belgium (25.7%). Among the African countries, the prevalence rates varied between 30.1 and 67.6%. Prevalence to the V3 loop derived from the SIVcpz-ant strains was much lower. Prevalence of sera reactive to the ANT-70 V3 loop peptide was very low, and the highest rates were observed in Cameroon (10.2%), Niger (6%) and Gabon (4.6%). Only the sera reactive to the ANT-70 V3 loop peptide from Cameroon and Gabon were confirmed on a specific HIVANT-70 Western blot (i.e., presence of antibodies to the envelope protein gp 120). CONCLUSIONS: The extent to which different V3 peptide reactivity patterns reflect the circulation of different HIV-1 strains in a particular population is not yet clear. However, V3 peptide serology using the very specific V3 peptide of the HIVANT-70 is a good indicator of the very aberrant group O in a particular population.
Asunto(s)
Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Fragmentos de Péptidos/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales , República Democrática del Congo , Variación Genética , Anticuerpos Anti-VIH/sangre , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , América del Norte , Pan troglodytes , Fragmentos de Péptidos/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/aislamiento & purificación , Especificidad de la Especie , Viremia/inmunología , Viremia/virologíaRESUMEN
OBJECTIVES: To determine the neutralizing antibody patterns to HIV-1ANT70 (ANT70) and HIV-1IIIB (IIIB) in human sera obtained from HIV-1-infected individuals from different African countries and Belgium. Second, to correlate the presence of neutralizing antibodies in sera and their ability to bind to synthetic peptides derived from eight different HIV-1 V3 loop sequences. DESIGN AND METHODS: Forty sera from Belgium and 88 obtained from seven countries in Africa were tested for their ability to neutralize ANT70 (one of the most genetically divergent HIV-1 isolates documented), and IIIB. Sera found to cross-neutralize both viruses were further challenged with four HIV-1 field isolates. All sera were tested on a panel of V3 loop peptides obtained from different HIV-1 genotypes. RESULTS: Four patterns of sera were identified, including 33 (26%) sera not neutralizing any of the isolates, seven (5%) sera neutralizing only ANT70, 45 (35%) sera neutralizing only IIIB, and 43 (34%) sera cross-neutralizing both isolates. Sera capable of cross-neutralizing both ANT70 and IIIB consistently neutralized other field isolates tested, with a remarkable similarity in neutralizing antibody titre. A significantly higher number of sera cross-neutralizing both ANT70 and IIIB compared with sera lacking neutralizing antibodies, reacted simultaneously in enzyme-linked immunosorbent assays (ELISA) with three or more V3 loop peptides belonging to HIV-1 strains of different genotypes. However, none of the sera cross-neutralizing ANT70 and IIIB were reactive in ELISA with the ANT70 V3 loop peptide. CONCLUSION: These results suggest that despite pronounced genomic variation of the HIV-1ANT70 isolate, there are strongly conserved neutralizing epitopes situated outside the V3 loop that are shared by other HIV-1 isolates. These findings suggest that genetic variation might be surmountable in the design of a polyvalent HIV vaccine, if neutralizing antibodies are found to be correlates of protection in HIV infection.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Anticuerpos Anti-VIH/sangre , VIH-1/inmunología , Síndrome de Inmunodeficiencia Adquirida/sangre , África , Secuencia de Aminoácidos , Bélgica , Ensayo de Inmunoadsorción Enzimática , Genotipo , Anticuerpos Anti-VIH/inmunología , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Pruebas de Neutralización , Péptidos/síntesis química , Péptidos/inmunologíaRESUMEN
OBJECTIVES: To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d'Ivoire, and to determine the extent to which phylogenetic trees based on sequence information of part of the env gene containing the principal neutralizing domain are representative for documenting genetic variability. DESIGN: Phylogenetic comparison of 13 HIV-1 strains isolated from patients in Abidjan with previously documented HIV-1 strains of different geographic origin. METHODS: To sequence a 900 base-pair fragment of the env gene containing V3, V4, V5 and the beginning of gp41 of three to four clones per isolate. Phylogenetic tree analysis was performed with the software package TREECON. RESULTS: Eleven HIV-1 isolates of Abidjan were classified as genotype A, while two were classed as genotypes B and D. Intra-genotype A distances at the nucleotide level were a maximum of 14.1%. Inter-genotype distances between genotype A and genotypes B, C, and D varied from 16.0 to 22.6%. Phylogenetic trees, based on sequence data of a 300 base-pair fragment containing the V3 loop, showed significant differences in tree topology and statistical confidence with phylogenetic trees based on sequence data of the 900 base-pair env fragment. CONCLUSIONS: Genotype A Côte d'Ivoire HIV-1 strains, which comprise 11 out of 13 isolates, predominate in Abidjan, which may indicate a local burst of particular variants. Phylogenetic trees should be interpreted with caution when based on a more limited number of nucleotides, such as the V3 region.
Asunto(s)
Genes env , Variación Genética , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/microbiología , VIH-1/genética , Fragmentos de Péptidos/genética , Secuencia de Bases , Côte d'Ivoire , ADN Viral , VIH-1/clasificación , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , FilogeniaRESUMEN
Three children are described in whom pre-transfusion samples were HIV-seronegative and post-transfusional samples, obtained within 1 week after transfusion, were HIV-seropositive. Two of them developed a transient fever within 1 week of receiving the blood transfusion, and a transient generalized skin eruption which lasted for about 2 weeks. All three developed persistent generalized lymphadenopathy. One child developed a lumbar herpes zoster 7 months after transfusion. IgM Western blots demonstrated the presence of antibodies to protein bands p17, p24 and p55 in all three children. These three case reports suggest that children who receive a seropositive blood transfusion are at high risk for developing acute manifestations of HIV infection.