Author Archives: Dan Frost

Physiology of normal erectile function

Physiology of normal erectile function and Viagra Penile erection is the most obvious feature of the male body’s response to sexual excitement. It is a complex neurovascular response, influenced by cognitive inputs and facilitated by testosterone [12]. Other features of that response include increases in skin temperature, blood pressure, hear t and breathing rates, facial […]

An overview of the disease perspective

The logic of the disease perspective is, strictly speaking, categorical. Its goal is to group conditions into diagnostic categories based on the pathological conditions found in individuals. Ultimately, the disease perspective seeks to state whether a person has—or does not have— a particular disease. Does this person have tuberculosis, yes or no? To make this […]

Immunofluorescence assay (IFA)

PHFAs were cultured on poly-L-lysine-coated 2-chamber glass slides, and the infection was performed as described above. The procedure of immunofluorescence assay has previously been described. Briefly, PHFAs infected with or without HHV-6A were fixed in 4% paraformaldehyde (in PBS), permeabilized in 0.5% Triton X-100 (in PBS), and stained with the anti-gp60/110 monoclonal antibodies (Chemicon international) […]

HHV-6A activates PARP cleavage and up-regulates bax/bcl-2 ratio. Part 3

In addition, NF-κB reportedly induces the expression of c-IAP1, c-IAP2 and XIAP, thereby promoting NF-κB activation in a positive feed-back system. NF-κB up-regulation exerts an anti-apoptotic effect leading to cells survival, transformation, and resistance to radiation and drug therapies. In contrast, NF-κB down-regulation will break this feed-back loop and reduce the expression of c-IAP1, c-IAP2 […]

HHV-6A activates PARP cleavage and up-regulates bax/bcl-2 ratio. Part 2

HHV-6 was first isolated from peripheral blood mononuclear cells of patients with lymphoproliferative disorders and AIDS. There are two variants of HHV-6 (A and B) according to distinct genetic, immunological and virological characteristics. As with other virus, HHV-6 is able to induce apoptosis of host cells. Subsequent studies have demonstrated that HHV-6 has been shown […]

HHV-6A activates PARP cleavage and up-regulates bax/bcl-2 ratio

PARP is an established substrate for caspase-3 in the apoptotic events. Cleavage of PARP facilitates cellular disassembly and serves as a marker of cells undergoing apoptosis. Western blotting was used to detect endogenous full-length PARP (116 KD), as well as the large fragment (89 KD) of PARP resulting from caspase cleavage. As shown in Figure […]

HHV-6A causes productive infection in PHFAs

HHV-6A was used to infect PHFAs at comparable levels of virus DNA (1 × 108 copies/106 cells) as determined by quantitative PCR. HHV-6A-infected PHFAs showed typical cytopathic effects (CPE) such as cellular swelling and cell fusion at 72 h post-infection (hpi). To further determine HHV-6A infection in PHFAs, the expression of a late protein gp60/110 […]

Human herpesvirus 6A induces apoptosis of primary human fetal astrocytes via both caspase-dependent and -independent pathways

Background Human herpesvirus 6 (HHV-6) is a T-lymphtropic and neurotropic virus that can infect various types of cells. Sequential studies reported that apoptosis of glia and neurons induced by HHV-6 might act a potential trigger for some central nervous system (CNS) diseases. HHV-6 is involved in the pathogenesis of encephalitis, multiple sclerosis (MS) and fatigue […]

Neutralization activity. Part 2

DNA vaccine has been demonstrated as a promising vaccination strategy for various viral infections. Previous studies have shown good immunogenicity and protection efficacy of hantavirus DNA vaccine. Hooper et al. demonstrated that DNA vaccination with a plasmid containing a cDNA representing the Seoul virus (SEOV) M segment elicited neutralizing antibody responses in mice and hamsters. […]

Neutralization activity

Neutralizing antibodies, which conferring protective immunity induced by DNA vaccine plasmids against hantavirus were evaluated by microneutralization assays. Pre-immune sera from all the groups exhibited no neutralizing activity. In contrast, immune sera collected 21 days after the first immunization with 100 μg of HTNV DNA vaccine plasmids in the presence or absence of CpG motifs […]