Fabrication and characterization of a multichannel 3D thermopile for chip calorimeter applications.

Thermal sensors based on thermopiles are some of the most robust and popular temperature sensing technologies across industries and research disciplines. A chip calorimeter with a 3D thermopile layout with a large sensing area and multichannel capacity has been developed, which is highly desired for many applications requiring large reaction chambers or high throughputs, such as biofilm research, drug screening, etc. The performance of the device, including temperature sensitivity and heat power sensitivity, was evaluated. The capability to split the chip calorimeter to multiple channels was also demonstrated, which makes the chip calorimeter very flexible and powerful in many applications.

Requirements for simian immunodeficiency virus antigen-specific in vitro proliferation of T cells from infected rhesus macaques and sooty mangabeys.

The measurement of cell-mediated immunity against the etiologic agent of human AIDS (HIV) in the non-human primate model of AIDS (simian immunodeficiency virus, SIV) has been difficult. In general, culture of peripheral blood mononuclear cells from HIV-1- and SIV-infected humans and monkeys, respectively, with purified inactivated HIV and SIV virus preparations has given inconsistent or negative proliferative responses. However, we describe herein an assay which consists of coculturing monocytes that have been pulsed with inactivated SIVsmm with nylon-wool-purified autologous T cells, leading to antigen-specific T-cell proliferation. The proliferative response, which predominantly occurs in CD4+ T cells, is major histocompatibility complex (MHC) class II-restricted and requires antigen processing. This assay will greatly facilitate the identification of the immunodominant epitopes recognized by T cells in sooty mangabeys, which are naturally infected but remain clinically asymptomatic, and in rhesus macaques, in which experimental infection leads to clinical symptomatology similar to human AIDS, eventually resulting in death.

Granular natural-killer cells develop into mucus-secreting cells.

Colonies of granular natural-killer cells selectively develop in lymph-node cell cultures of nude mice after stimulation with rat T-cell growth factor. When these cells are grown on X-irradiated monolayers prepared from 16-18-day-old mouse embryos, they are triggered to synthesize and secrete a sulphated glycoprotein that can be identified as mucus. As a result of an erosive process of the granules, the mucoid material accumulates in pools in the cytoplasm matrix. The secretion is operated through a process of budding of double-membrane-bound vesicles. The successful triggering of mucous synthesis is interpreted by the successful growth of those mesenchymal cells in the embryonic monolayer that function in the induction of epithelial morphogenesis in the developing embryo.

Characteristics of clients attending confidential versus anonymous testing clinics for human immunodeficiency virus.

OBJECTIVES: To compare risk behavior between subjects attending anonymous and confidential clinics for human immunodeficiency virus testing, and to assess whether anonymous testing results in a higher accrual of persons at risk for HIV. METHODS: An anonymous questionnaire that addressed sociodemographic and risk behavior aspects was administered to 140 subjects attending an anonymous clinic and 124 attending a confidential clinic in the Tel Aviv area. A logistic regression analysis was used to compare the effects of various behavioral factors on the probability of attending each clinic. RESULTS: Chronological age, age at first sexual intercourse, and the percent of married subjects were similar in both clinics. However, there was a significant difference in the sex ratio and in educational attainment (85.0% versus 55.6% were males, P < 0.001; and 58% vs. 34% had over 12 years of education, P < 0.001, in the anonymous and confidential clinics respectively). There was a striking difference between the two clinics with regard to sexual experience characteristics: of the subjects reaching the anonymous clinic 21.4% were homosexual and 10.0% bisexual versus a total of 2.6% in the confidential clinic. A logistic regression analysis, comparing the effects of various behavioral factors on the probability of attending each clinic, showed that gender (male), high education, homosexuality, number of partners and sexual encounter with sex workers were the strongest predictors for selecting anonymous HIV examination. CONCLUSIONS: Individuals at high risk for HIV, such as homosexuals and bisexuals, prefer to attend an anonymous clinic.

Inhibition of SIV/SMM replication in vitro by CD8+ cells from SIV/SMM infected seropositive clinically asymptomatic sooty mangabeys.

Several investigators have demonstrated the ability of CD8+ T cells from HIV-1 infected humans and SIV infected rhesus macaques to inhibit viral replication in vitro. In this report we show that CD8+ cells from naturally SIV infected sooty mangabeys also have the ability to inhibit viral replication in vitro. In addition, initial experiments which seek to elucidate the mechanism and antigen specificity of CD8-mediated suppression are described.

Comparison of SIV/SMM replication in CD4+ T cell and monocyte/macrophage cultures from rhesus macaques and sooty mangabeys.

Monocytes from SIV/SMM infected sooty mangabeys and rhesus macaques were incubated in vitro with live SIV/SMM. The reverse transcriptase (RT) activity in the supernatant fluids of the monocyte cultures of the former species was higher than the RT activity in the latter species. No differences were found in the supernatant fluid of similar cultures of CD4+ T cells from both these species. Autologous (but not allogeneic) CD8+ T cells from SIV infected mangabeys and rhesus macaques inhibited SIV replication in vitro. The suppression appeared more marked in monocytes from the mangabey species. These in vitro differences may relate to the clinically asymptomatic state of the sooty mangabeys and the disease-susceptible state of the rhesus macaques.

Identification of SIV/SMM viral proteins that induce T cell response in experimentally infected rhesus macaques and naturally infected sooty mangabeys by the cellular western blot assay.

Initial studies have revealed subtle differences in the T cell proliferative response to whole SIV antigen in the peripheral blood mononuclear cells (PBMC) from sooty mangabeys and rhesus macaques. Preliminary findings utilizing the cellular Western blot assay are described.