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PubMed1995

Research on disclosure of HIV status: cultural evolution finds an ally in science.

This editorial responds to Mason et al.'s (1995) "Culturally Sanctioned Secrets: Latino Men's Nondisclosure of HIV Infection to Family, Friends, and Lovers." Culture is an evolving dynamic phenomenon shaped by society, psychology, and history. Historically, familism and simpatía have been Hispanic cultural assets. As times change, however, values and behaviors that served a culture for generations may become liabilities unless they evolve to fit the changing world of the culture. In the case of Hispanic gay men, the desire to protect family members is a barrier to disclosure of HIV status. Mason et al.'s study points to areas in which cultural development is needed. Science and culture thus become allies, with science pointing the way to needed directions for adaptive cultural evolution.

Acculturation↗
PubMed1993

[Cryptococcosis of the central nervous system and infection by HIV. Clinical-evolutive characteristics in 13 cases].

Cryptococcosis is the fourth cause of infection of the Central Nervous System in patients with infection by HIV. Despite this fact, the series published in our country are referred to a limited number of cases. We describe the most relevant characteristics of 13 patients with meningitis by Cryptococcus neoformans. We used as inclusion criteria a positive culture of the Cephalorhachidian Fluid (CRF). We observed a significant reduction in the levels of CD4 lymphocytes in all patients, the absence of meningitic syndrome in more than 50% cases (8/13) and a normal CRF cytobiochemistry in three patients. The thoracic radiography was normal in all cases but two, although the cryptococcus was cultured in a transbronchial biopsia of a patient with normal thoracic radiography. The Computerized Axial Tomography showed frequent alterations (5/13). Eight patients were treated with amphotericin B (0.5 mg/kg/d) and five with fluconazol (400 mg/day). Despite following a maintenance therapy with fluconazol (200 mg/d), we had two cases of recurrence in the group previously treated with fluconazol. The level of leukocytes in the CRF was the only prognosis factor (p < 0.05). Five patients died during their first hospitalization due to causes related to the infection by cryptococcus. New therapeutical guidelines are needed in order to improve the prognosis of these patients.

AIDS-Related Opportunistic Infections↗
PubMed1993

The fastest genome evolution ever described: HIV variation in situ.

Human immunodeficiency virus is an RNA virus in which the degree of genetic variation observed is phenomenal--up to 20% within an infected individual. This is essentially due to remorseless cycles of viral replication, most probably due to chronic activation of the immune system. It can be estimated that the number of variants in existence worldwide must be in excess of 10(14)-10(18), and given the nature of RNA viruses even more novel variants should emerge.

Biological Evolution↗
PubMed1988

AIDS evolution.

Explore the source record for details and available documents.

HIV↗
PubMed1995

[Blood donors seropositive for type 1 human immunodeficiency virus (HIV-1). Epidemiologic characteristics and clinical course].

PURPOSES: To evaluate retrospectively the epidemiologic profile and clinical course of the HIV-positive voluntary blood donors in the Sant Pau's Hospital Blood Bank (Barcelona-Spain) between 1986 and 1993. PATIENTS AND METHODS: A total of 119,345 blood donors were studied, and fifty seven such cases were identified. Risk behavior, causes of failure of the pre-donation procedures and clinical stage were analyzed. A follow-up of their infection was performed by the Infectious Disease Unit. RESULTS: The mean age of 57 seropositive donors was 31 +/- 8 years. Prevalence of HIV-1 infection among donors was 0.48 per 1000. Forty four (77%) were male and 13 (23%) female. Forty three (75%) were first time donors while 14 (25%) were repeat donors. The causes for the failure of the self-deferral questionnaire were: 42 subjects did not consider that they had engaged in "risk" behavior, seven donors lied in order to know if they were HIV carriers and two cases were driven to donate due to social or family pressure. The distribution of these donors according to risk behaviour was: 30 (53%) heterosexual, 11 (20%) homosexual, 11 (20%) intravenous drug users and five (7%) with no identified risk. It was noted that HIV infection progressed more rapidly to AIDS in HIV - positive homosexual donors than in heterosexual subjects (p < 0.05). CONCLUSIONS: Heterosexual donors who maintain sexual contacts with different partners without prophylactic measures for HIV infection currently represent the highest risk group for transfusion-related HIV infection. Clinical evolution of HIV infection was faster and more devastating in the homosexual group than in the heterosexual group.

Adult↗
PubMedDate not supplied

[The evolutionary profile of HIV infection in children].

The evolution of HIV infection in children is bimodal, not depending on the vertical or horizontal route of transmission and with no assemblence with AIDS evolution in adults. The contaminated children with fast evolution to death in maximum two years, develop a severe neurological and infectious symptomatology. The others even symptomatic show slowly evolution with not so frequent and not so serious acute infectious. The natural history of the HIV infection in children of our country will be better defined in the future for now it is observed only for three years.

Child, Preschool↗
PubMed1991

[Immunologic profile of HIV-2 seropositive African individuals (follow-up)].

In the geographic distribution of HIV-2, it is known that this infection is most prevalent in West Africa. Since 1986 we have studied seropositive and seronegative clusters, in Guinea-Bissau with follow-ups in 1988, 1989, 1990 and 1991. Analysis of the results show the high incidence of this infection. 8.51% of the 4,372 people of the general population studied were seropositive, showing the high predominance of HIV-2 infection. Only 4 cases were exclusively reactive to HIV-1 and a slow evolution of HIV-1 infections. In the seroconversions of HIV-2 infections the antibodies appeared first to the core components and secondly to the surface glycoproteins. Some of the laboratory parameters affected in the evolution of the infection include a gradual increase in immunoglobulins and a decrease in CD4 lymphocytes and in the CD4/CD8 ratio. A comparison of these variations in HIV-2 infected people, with or without cross-reactivity to HIV-1, reveals that they are much more evident in exclusively HIV-2 positive people. This fact can indicate that the variants responsible for the cross-reactions are less pathogenic and phylogenetically less developed.

Africa, Western↗
PubMed1994

Identification of three feline immunodeficiency virus (FIV) env gene subtypes and comparison of the FIV and human immunodeficiency virus type 1 evolutionary patterns.

Feline immunodeficiency virus (FIV) is a lentivirus associated with AIDS-like illnesses in cats. As such, FIV appears to be a feline analog of human immunodeficiency virus (HIV). A hallmark of HIV infection is the large degree of viral genetic diversity that can develop within an infected individual and the even greater and continually increasing level of diversity among virus isolates from different individuals. Our goal in this study was to determine patterns of FIV genetic diversity by focusing on a 684-nucleotide region encompassing variable regions V3, V4, and V5 of the FIV env gene in order to establish parallels and distinctions between FIV and HIV type 1 (HIV-1). Our data demonstrate that, like HIV-1, FIV can be separated into distinct envelope sequence subtypes (three are described here). Similar to that found for HIV-1, the pairwise sequence divergence within an FIV subtype ranged from 2.5 to 15.0%, whereas that between subtypes ranged from 17.8 to 26.2%. However, the high number of synonymous nucleotide changes among FIV V3 to V5 env sequences may also include a significant number of back mutations and suggests that the evolutionary distances among FIV subtypes are underestimated. Although only a few subtype B viruses were available for examination, the pattern of diversity between the FIV A and B subtypes was found to be significantly distinct; subtype B sequences had proportionally fewer mutations that changed amino acids, compared with silent changes, suggesting a more advanced state of adaptation to the host. No similar distinction was evident for HIV-1 subtypes. The diversity of FIV genomes within individual infected cats was found to be as high as 3.7% yet twofold lower than that within HIV-1-infected people over a comparable region of the env gene. Despite these differences, significant parallels between patterns of FIV evolution and HIV-1 evolution exist, indicating that a wide array of potentially divergent virus challenges need to be considered in FIV vaccine and pathogenesis studies.

Adaptation, Biological↗
PubMed1993

[HIV infection among type A and B hemophiliacs].

Evolution of HIV infection was studied in 480 hemophiliacs A and 78 hemophiliacs B treated in the "Centre-West" Region. 23.3% hemophiliacs A and 46.1% hemophiliacs B were contaminated by HIV. In this region, HIV seroprevalence in hemophiliacs A was lower than the prevalence noted at the national level (51.2%); this is certainly due to the use of frozen cryoprecipitates in the treatment of a high number of hemophiliacs A. A higher number of hemophiliacs B developed the disease: 12.5% hemophiliacs A versus 22% hemophiliacs B. Moreover hemophilic B patients had a more rapid evolution towards the disease since 6 out of 14 hemophiliacs A and 7 out of 8 hemophiliacs B with AIDS died. The fact that hemophiliacs B were significantly older than hemophiliacs A might be one of the reasons, but it must be noted that the contamination often occurred earlier in hemophiliacs B and was perhaps more important. The more severe evolution in the hemophiliac B group noted in our region is not found in American studies, which may be due to the different ways of preparing Factor IX concentrates in France and the United States.

Adolescent↗
PubMed1988

Seroepidemiology of human immunodeficiency viruses in Africa.

The first generation of serological tests for anti-HIV-1 gave so many false positives with African sera that it was wrongly postulated that the virus was endemic in Africa. As there is no simian or other virus sufficiently closely related to HIV-1 as to suggest a recent common ancestor, the evolution of HIV-1 is obscure and there is no current evidence to support the hypothesis of an African origin. However, the similarity of HIV-2 to SIV and its geographical distribution do suggest an evolution of this virus in west Africa. The earliest anti-HIV-1 positive serum was from a subject in Kinshasa in 1959. Seroprevalence rose in pregnant women in Kinshasa from 0.25% in 1970, to 3.0% in 1980 and 5.7% in 1986. When two sexually promiscuous groups are compared, seropositivity rose sharply in female prostitutes in Nairobi from 4% in 1981, to 59% in 1984 and 64% in 1986, a curve which is approximately parallel to, but three years later than that of homosexual males in San Francisco. In central and east Africa, HIV-1 is now epidemic from Congo to Kenya and from Uganda to Zimbabwe. In west Africa, both HIV-2 and HIV-1 are epidemic: seroprevalence of HIV-2 is highest in southern Senegal, Guinea-Bissau and Côte d'Ivoire: HIV-1 has the highest frequency in Côte d'Ivoire and Ghana. HIV-2 has not been reported, and HIV-1 is pre-epidemic in Africa north of the Sahara, Nigeria, Angola, Mozambique and southern Africa, being found at significant frequency only in female prostitutes, patients with STD, or, in Morocco and South Africa only, in male homosexuals. Seroprevalence is greatest in female prostitutes and patients with STD: infection is more frequent in urban than in rural populations, except in Uganda. The peak frequency is at 30-34 yr in males and 20-24 yr in females. Other groups at risk are infants born to infected mothers, and those requiring blood transfusions, especially pre-school children, patients with sickle-cell disease and pregnant women. The doubling time for seropositivity is about one year in the sexually active age range in some populations. Even at existing seroprevalence, decimation or worse of the most productive age groups is inevitable during the next few years in certain countries.(ABSTRACT TRUNCATED AT 400 WORDS)

AIDS Serodiagnosis↗
PubMed1994

Certain HLA-DR5 and -DR6 major histocompatibility complex class II alleles are associated with a CD8 lymphocytic host response to human immunodeficiency virus type 1 characterized by low lymphocyte viral strain heterogeneity and slow disease progression.

Either of two structurally related major histocompatibility complex class II alleles, DRB1*1102, which encodes a DR5 specificity, or DRB1*1301, which encodes a DR6 specificity, was found in 67% of individuals responding to human immunodeficiency virus type 1 (HIV-1) infection with a syndrome characterized by persistent circulating and diffusely infiltrative CD8 lymphocytosis (DILS), slow progression to opportunistic infections, and delayed CD4 T-cell depletion. These alleles were present in only 28% of ethnically matched HIV-positive controls (P = 0.001). The frequency of DRB1*1301 was increased in both Blacks and Caucasians with this syndrome, while that of DRBI*1102 was increased only in Blacks, where 80% had either of these alleles. To investigate whether the host response associated with these alleles influences the evolutionary divergence of the HIV-1 genome, sequencing of the envelope V3 loop was performed. This revealed a significantly diminished lymphocyte viral heterogeneity compared with random HIV+ controls matched for CD4 T-cell levels. These results suggest that the immunogenetics of the host influence the nature of the immune response to HIV-1, which may lead to constrained evolution of HIV-1 gene products. Of possible relevance, the alpha-helical third diversity region common to both the DRB1*1102 and DRB1*1301 allelic products was noted to have homology with the C-terminal region of the HIV-1 envelope V3 loop at six of nine consecutive residues. This suggests the possibility that these alleles may bias the anti-HIV T-cell receptor repertoire through a mimicry mechanism.

Alleles↗
PubMed1990

Molecular cloning and characterization of a German HIV-1 isolate.

The genetic diversity of HIV-1 is well documented. Except for the HIV-1 isolate LAV-1BRU, no nucleic acid sequence of a European isolate of HIV-1 has been published to date. To further investigate the extent of the genetic variability and the evolution of HIV-1, we have isolated, cloned, and subsequently sequenced HIV-1 from a German patient with AIDS-related complex. Comparative studies of the nucleic acid sequence revealed that this isolate, designated HAN2, is highly divergent from the North American and African subtypes of HIV-1 and may represent a European subtype of HIV-1. Furthermore, a full-length molecular clone was derived from this isolate which was infectious in human T-cell lines. Therefore this new isolate will be particularly useful for studies on the genetic evolution and biology of HIV-1 as well as for testing antiviral substances and for developing vaccines.

Amino Acid Sequence↗
PubMedDate not supplied

Mathematical model for the AIDS epidemics evolution in Romania.

The individuals are distributed in 9 risk groups (adults and children), in which an HIV transmission way is predominant. Taking into account a simplified graph of the HIV infection evolution, kinetic equations for the number of individuals from each risk group--situated in various stages of HIV infection--are written. The approximative solutions of these equations give us: the characteristic exponents of the temporal evolutions of the main and secondary local epidemics; the ratios Ci/Bi and Di/Bi of asymptomatically contaminated and dead (as consequence of AIDS) versus symptomatically contaminated; the onset of local epidemics in various risk groups; the relative amplitude of the secondary local epidemics versus the main local ones.

Acquired Immunodeficiency Syndrome↗
PubMed2026

Evolutionary dynamics of HIV-1 recombinants: analysis of contemporary and historical viral populations in East Africa.

BACKGROUND: Understanding the genetic evolution of HIV-1 Transmitted/Founder (T/F) virus is crucial for developing effective treatment and prevention strategies due to its rapid mutation and recombination rates. METHODS: This study compared the genetic diversity of 24 contemporary T/F viruses collected between 2016 and 2021 in Uganda and Kenya with 29 historical T/F sequences sampled between 2006 and 2011. RESULTS: Subtype analysis based on near-full-length (NFL) HIV-1 T/F genomes revealed that 57.1% (12/21) of contemporary viruses were recombinants, predominantly involving Subtype A1, D, and increasing Subtype C, with 33.3% (7/21) being A1D recombinants (A1&#x2009;>&#x2009;D) and 19% (4/21) classified as complex recombinants involving three or more subtypes. Historical viruses showed a similar overall proportion (69%) but were mainly A1D mosaics (D&#x2009;>&#x2009;A1) with recombination confined primarily to the envelope region. In contrast, contemporary viruses shifted towards more complex recombinant patterns affecting additional genomic regions, including pol and accessory genes. Phylogenetic analysis demonstrated that contemporary viruses clustered into distinct, well-supported (98% bootstrap) sub-branches, suggesting divergency attributed to an imbalance in their proportions of subtype A1 and D sequences as well as a different content of A1 and D segments in the A1/D mosaic recombinants. CONCLUSIONS: These findings underscore the dynamic and shifting nature of HIV-1 genetic diversity in East Africa, highlighting the need for continuous molecular surveillance and region-specific treatment guidelines.

HIV-1↗
PubMed1992

[HIV-1 infection in patients with hemophilia. The Argentinian experience from 1983 to 1990].

We present studies on the evolution of HIV-1 infection in 638 hemophilic patients receiving commercial antihemophilic concentrates (CAH) at the Institute of Hematological Research and the Argentine Foundation of Hemophilia between 1983 and 1990. Positive serology for HIV-1 was detected in 30% of the patients studied. Prevalence of HIV-1 infection was higher (about 70%) in the group with severe hemophilia requiring more CAH, but there were no differences between patients with hemophilia A or B. Sexual transmission was demonstrated in 8/64 women (13%) with stable sexual relationship with HIV-1 + hemophilic patients. Three of them became pregnant, and HIV-1 infection was demonstrated in two of the three children. In general, the clinical evolution, as well as the hematologic and immunologic parameters of infected patients were similar to those described for the hemophilic population in other occidental countries. Opportunistic infections were also those observed elsewhere (with predominance of P. carinii pneumonia and disseminated Candida infections). However, the presence of fatal chagasic encephalitis in two of the patients with AIDS is unusual. Thus, central nervous system localization of T. cruzi (which can be observed during the acute period of T. cruzi infection or in immunosuppressed patients), must be considered as a possible severe complication of HIV-1 disease in T. cruzi infected patients.

AIDS-Related Opportunistic Infections↗