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Data on the involvement of the ocular surface and its relationship with Coronavirus disease 2019 (COVID-19) are still minimal and not univocal. The respiratory tract is the structure most affected by COVID-19, and the serious form of the disease is characterized by severe pneumonia, acute respiratory distress syndrome and hypercoagulation. However, accumulating evidence shows that other organs could be reached by the virus, thus causing further comorbidities. To date, the exact route / routes of transmission of COVID-19 are still unclear. The respiratory tract is probably not the only route of transmission for this viral infection and some authors have also speculated that COVID-19 droplets, or infected hands, could contaminate the conjunctiva, which could therefore represent the initial site of an infection spread. Theoretically, the role of the ocular surface, a biological site still relatively unexplored, appears scientifically relevant in understanding the Severe Acute Respiratory Syndrome - Coronavirus – 2 (SARS-CoV-2) infection. The purpose of this paper is to summarize the current literature in order to elucidate the potential role of tear and conjunctival sampling to detect SARS-CoV-2 for the diagnosis of COVID-19 and to monitor patients during follow-up.

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Background: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) represent the most common agents of sexually transmitted pharyngeal infections. These conditions are frequently asymptomatic, acting as important reservoir for further transmission. The aim of this study was to assess the prevalence and predictors of pharyngeal infections due to CT and NG in a cohort of patients attending a STI Clinic in the North of Italy. Materials/methods: From January 2016 to September 2018, all the consecutive patients attending the STI Outpatients Clinic of St. Orsola-Malpighi Hospital (Bologna) and reporting unsafe oral intercourses were considered eligible for the study. After a clinical examination, a pharyngeal swab for the molecular detection of CT and NG (Versant CT/GC DNA 1.0 Assay; Siemens) was collected from each patient. Moreover, on the basis of patients’ sexual behavior and symptoms, urine samples and/or ano-rectal swabs for CT/NG detection were collected. In case of a CT positivity, a molecular genotyping based on omp1 gene PCR, was performed. Results: During the study period, 893 patients (119 females and 774 MSM) were enrolled. Globally, a total of 134 cases of gonorrhoea (15%) and 34 chlamydial infections (3.8%) were detected in the pharyngeal site, with no significant differences between males and females. More than 90% of the pharyngeal infections were completely asymptomatic and the presence of symptoms was not a predictor of a pharyngeal infection (P=0.7). On the contrary, a history of sexual contacts with a partner positive for CT and/or NG (P

The aim of our study was to assess risk factors associated with vitamin D deficiency among HIV-1-infected patients on combination antiretroviral therapy (cART). A retrospective, case-control study was conducted to assess risk factors associated with vitamin D deficiency among HIV-1-infected adults on stable cART. Vitamin D deficiency was defined as 25-OH vitamin D concentration 600 cells/mm3 and current HIV RNA

A growing body of evidence indicates that proviral DNA load quantitation is an important parameter in establishing the dynamics of HIV infection. Proviral DNA load can be determined during the follow-up of infected individuals to evaluate reservoir status in addition to viral replication. Hence, the study of viral reservoirs, represented by HIV-1 latently infected cells, including resting memory CD4+ T cells, monocytes and macrophages, by which HIV-1 can be reactivated, opens new perspectives in the assessment and the comprehension of HIV-1 infection. However, the identification of viral reservoirs, that can store both wild and drug resistance viruses, is one of the most important steps in developing treatment strategies because it is now clear that viral reservoirs not only prevent sterilizing immunity but also represent a major obstacle to curing the infection with the potent antiretroviral drugs currently in use. Even if only careful evaluation of virological and immunological markers is necessary to fully characterize the course of HIV-1 infection and to provide a more complete laboratory-based assessment of disease progression, the availability of a new standardized assay such as DNA proviral load will be important to assess the true extent of virological suppression in treated patients and to verify the efficacy of new immune-based therapies aimed at purging HIV-1 DNA reservoirs. Several studies demonstrate, in fact, that HIV-1 cellular DNA load may be an indicator of spread of infection whereas the plasma RNA load is indicates active infection. This article will review the importance of monitoring HIV-1 proviral load DNA during the follow-up of HIV-1 infected subjects, suggesting that additional information complementing HIV RNA load could provide crucial information to monitor viral replication and the effectiveness of HAART therapy.

Many studies have demonstrated that HIV-1 Tat plays a pivotal role both in the HIV-1 replication cycle and in the pathogenesis of HIV-1 infection. Indeed, Tat affects the HIV-1 replication cycle regulation increasing the proviral transcription rate several hundred-fold and acting on the elongation of viral transcripts. Moreover, Tat displays several important biological activities committed to uninfected and infected cells by a paracrine/autocrine mechanism due to secretion of Tat from infected cells. In particular, Tat modulates the expression of several cellular genes and triggers the activation of some signal transduction pathways and transcription factors suggesting a complex role in the scenario of HIV-1 infection. This review focuses on some aspects of Tat biological activity with particular regard to effects of Tat on cell proliferation and survival regulation.

We construct biorthogonal polynomials for a measure over the complex plane which consists in the exponential of a potential V(z,z*) and in a set of external sources at the numerator and at the denominator. We use the pseudonorm of these polynomials to calculate the resolvent integral for correlation functions of traces of powers of complex matrices (under certain conditions)., latex Poly3.tex, 1 file, 25 pages http://www-spht.cea.fr/articles/T04/042 [SPhT-T04/042]

In order to compare HIV-1 p24 antigenemia and plasma HIV-1 RNA levels as markers of viral replication, 3,129 paired determinations of alkaline immunocomplex-dissociated serum HIV-1 p24 antigenemia (performed with an immunoenzymatic assay), and plasma HIV-1 RNA levels (carried out with a branched DNA method, a reverse transcriptase-coupled polymerase chain reaction, and a nucleic acid sequence-based assay) were assessed over a two-year-period. When excluding samples with undetectable plasma HIV-1 RNA levels (which tested negative or borderline positive at serum p24 antigen assay in 97.9% of cases), immunocomplex-dissociated p24 antigenemia proved significantly less sensitive than viral load at all considered HIV-1 RNA reference levels, although the profile of positive serum p24 antigen assays (values above 10 pg/ml) paralleled the trend of plasma HIV-1 viral load, especially at higher levels. However, serum HIV-1 p24 antigenemia (even after immunocomplex dissociation) can be longer suggested as a the sole virological tool in the laboratory management of HIV-1 infection, due to its significantly lower sensitivity levels compared with viral load assessment.

In situ polymerase chain reaction represents an intriguing method to couple the sensitivity of PCR technology with the preservation of cell morphology. The target of this technique is the detection of specific DNA or retrotranscribed RNA inside the cell. In this brief report, we describe an in situ polymerase chain reaction technique revealed by flow cytometry in order to reveal the human immunodeficiency virus type 1 (HIV-1) proviral DNA in peripheral blood mononuclear cells. We also discuss the key steps and parameters of our assay in comparison with current opinion on in situ polymerase chain reaction.

Starting from our previous observations that the HIV-1-mediated engagement of CD4 induced apoptotic death of TF-1 hematopoietic progenitor cells, in this study we evaluated PKC activity and intracellular Ca2+ levels in TF-1 cells treated with viable and heat-inactivated HIV-1 (strain IIIB) or anti-CD4 Leu3a monoclonal antibody (mAb). Both viable and heat-inactivated HIV-1 or anti-CD4 mAb, but not anti-human cytomegalovirus (HCMV) 66kD protein or anti-CD8 mAb induced a rapid (5-10 min) increase in PKC activity under both serum-containing and serum-free conditions. The same treatment also induced both a transient and a long-lasting (48 hours) decrease (p0.05) in intracellular Ca2+ levels in serum-containing cultures. We propose that the observed changes in PKC activity and intracellular Ca2+ levels might be involved in the HIV-1 mediated apoptosis of hematopoietic progenitor cells.

The production of granulocyte/macrophage-colony stimulating factor (GM-CSF), interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF-alpha) were evaluated in the supernatants of short-term cultures of purified CD4+ T-lymphocytes and enriched monocytes obtained from peripheral blood (PB) of 35 HIV-1 seropositive (+) asymptomatic individuals, stages I-II of the Walter Reed (WR) classification, 15 HIV (+) symptomatic patients (WR V-VI) and 40 HIV-1 seronegative normal blood donors. IL-1 beta and TNF-alpha production by either enriched monocytes or isolated CD4+ T-cells, was similar in HIV-1 (+) asymptomatic, symptomatic subjects and normal controls. GM-CSF level in enriched monocyte culture supernatants did not show any significant difference in the three groups of subjects under investigation. On the other hand, GM-CSF production by isolated CD4+ T-lymphocytes was two-fold decreased in HIV-1 (+) asymptomatic subjects and five-fold decreased in HIV-1 (+) symptomatic patients with respect to normal blood donors. The decline in GM-CSF production was clearly correlated with viral isolation from patient's PB light density mononuclear cells (r = -0.920, p less than 0.01). The selective and progressive decline in GM-CSF production by CD4+ T-lymphocytes, starting from early stages of HIV-1 infection, suggest a preferential lesion of a specific subset of CD4+ T-lymphocytes characterized by an intense production of GM-CSF and may contribute to explain the deranged inflammatory and immune responses which characterize the course of HIV-1 infection.

In order to establish whether endothelial cells are involved in immunodeficiency virus type 1 (HIV-1) infection, we performed a virological study on endothelial cells isolated from human adipose tissue and infected with HIV-1 in vitro. Supernatants from cultures showed a reverse transcriptase activity starting one day after HIV inoculation. Viral rescue was significantly impaired in cycloheximide treated cells confirming a de novo synthesis of viral products.