A randomized controlled study to compare analgesic efficacy of sublingual buprenorphine and intravenous tramadol in patients undergoing mastectomy.

Sublingual (SL) buprenorphine is approved for managing acute postoperative pain, characterized by easy administration, good pain relief and good patient compliance. We hypothesized that SL buprenorphine would be a better perioperative analgesic compared to intravenous (IV) opioids like tramadol in patients undergoing mastectomy surgery for breast cancer. After institutional ethics committee approval, we randomized 60 patients with breast cancer into 2 groups. In buprenorphine group, patients received 200 µg of SL buprenorphine thrice daily and in tramadol group patients received 100 mg of IV tramadol thrice daily. The analgesic efficacy of SL buprenorphine was comparable to that of IV tramadol. Visual Analogue Scale scores had no significant difference between the two groups at various time frames (0, 1, 3, 6, 12, 18 and 24 hours) at rest and movement except at 0 and 3 hours during movement when the score was lower in the tramadol group than the buprenorphine group. Four patients in the buprenorphine group received rescue analgesic (IV morphine 3 mg). Analgesic efficacy of SL buprenorphine appears comparable to IV tramadol for managing postoperative pain after mastectomy. SL buprenorphine can be administered sublingually, which is an advantage.

Changes in QTc interval after hydroxychloroquine therapy in patients with COVID-19 infection: a large, retrospective, multicentre cohort study.

OBJECTIVE: To evaluate the extent of hydroxychloroquine-induced corrected QT (QTc) prolongation and its relation to COVID-19 infection severity and incidence of polymorphic ventricular arrhythmias and sudden arrhythmic deaths. DESIGN: A large-scale cohort study with retrospective analysis of baseline and on-therapy QT interval corrected using Bazett and Fridericia formulas. SETTING: A multicentre study involving eight secondary and tertiary care hospitals of the Abu Dhabi Health Services Company (SEHA), United Arab Emirates. PARTICIPANTS: 2014 patients consecutively admitted with PCR-confirmed SARS-CoV-2 infection between 1 March 2020 and 1 June 2020. INTERVENTIONS: Treatment with hydroxychloroquine alone or in combination with azithromycin for at least 24 hours and with a baseline ECG and at least one ECG after 24 hours of therapy. MAIN OUTCOME MEASURES: Maximal QTc interval prolongation and its relationship to clinical severity, polymorphic ventricular tachycardia and sudden arrhythmic death while on treatment. RESULTS: The baseline QTc(Bazett) was 427.6±25.4 ms and the maximum QTc(Bazett) during treatment was 439.2±30.4 ms (p<0.001). Severe QTc prolongation (QTc ≥500 ms) was observed in 1.7%-3.3% of patients (Fridericia and Bazett, respectively). There were no cases of polymorphic ventricular arrhythmia or hydroxychloroquine-related arrhythmic death. QTc prolongation was more pronounced in combination therapy compared with hydroxychloroquine alone (22.2 ms vs 11.0 ms, p<0.001) and in patients with higher COVID-19 clinical severity (asymptomatic: 428.4±25.4 ms, severe COVID-19 infection: 452.7±35.7 ms, p<0.001). The overall in-hospital mortality was 3.97% and deceased patients had longer on-therapy QTc(Bazett) than survivors (459.8±21.4 ms vs 438.4±29.9 ms, p<0.001). CONCLUSIONS: The incidence of severe QTc prolongation with hydroxychloroquine was low and not associated with ventricular arrhythmia. The safety concerns surrounding the use of hydroxychloroquine may have been overestimated; however, caution should be exercised when using hydroxychloroquine in patients with risk factors for QT prolongation.

Regional anesthesia prevents cancer recurrence after oncosurgery! What is wrong with the hypothesis?

Several studies have investigated the hypothesis of the efficacy of regional anesthesia (RA) techniques in preventing cancer recurrence when used perioperatively during oncological surgeries. Although theoretically, the association appears beneficial, the patient outcomes after cancer surgeries with or without RA were comparable, that is, the use of RA did not improve patient survival or prevent cancer recurrence after surgery. Another problem with this data is its retrospective nature which makes its interpretation difficult. Moreover, there are a lot of other confounding factors like comorbidities, tumor biology, nosocomial infections, duration of hospital stay, and baseline immunity, which is not comparable, and hence make standardization for a well-designed prospective study difficult. Return to intended oncologic therapy (RIOT) involves treatment in the form of radiation or chemotherapy which, if received on time after the planned oncosurgery, could provide a better chance of preventing cancer recurrence and improved survival. However, none of the retrospective studies have correlated cancer recurrence with delay in RIOT or not receiving RIOT as a cause of cancer recurrence. This paper discusses why even a well-designed, prospective trial could possibly never establish the efficacy of RA in preventing cancer recurrence and improving survival due to the complexities involved in a patient undergoing oncosurgery.

Dexmedetomidine in cancer surgeries: Present status and consequences with its use.

Dexmedetomidine is a centrally acting α2 adrenoreceptor agonist used in perioperative medicine due to its sedative, analgesic and sympatholytic properties. Recently animal data has pointed towards potential role of dexmedetomidine in promoting cancer recurrence and metastasis when used perioperatively especially after breast surgeries. This is because of presence of α2 adrenoreceptors in breast cancer tissue. We reviewed existing literature in which dexmedetomidine was used in cancer surgeries and investigated its role in recurrence and metastasis.

Effect of transcription inhibition and generation of suppressive viral non-coding RNAs.

BACKGROUND: HIV-1 patients receiving combination antiretroviral therapy (cART) survive infection but require life-long adherence at high expense. In chronic cART-treated patients with undetectable viral titers, cell-associated viral RNA is still detectable, pointing to low-level viral transcriptional leakiness. To date, there are no FDA-approved drugs against HIV-1 transcription. We have previously shown that F07#13, a third generation Tat peptide mimetic with competitive activity against Cdk9/T1-Tat binding sites, inhibits HIV-1 transcription in vitro and in vivo. RESULTS: Here, we demonstrate that increasing concentrations of F07#13 (0.01, 0.1, 1 µM) cause a decrease in Tat levels in a dose-dependent manner by inhibiting the Cdk9/T1-Tat complex formation and subsequent ubiquitin-mediated Tat sequestration and degradation. Our data indicate that complexes I and IV contain distinct patterns of ubiquitinated Tat and that transcriptional inhibition induced by F07#13 causes an overall reduction in Tat levels. This reduction may be triggered by F07#13 but ultimately is mediated by TAR-gag viral RNAs that bind suppressive transcription factors (similar to 7SK, NRON, HOTAIR, and Xist lncRNAs) to enhance transcriptional gene silencing and latency. These RNAs complex with PRC2, Sin3A, and Cul4B, resulting in epigenetic modifications. Finally, we observed an F07#13-mediated decrease of viral burden by targeting the R region of the long terminal repeat (HIV-1 promoter region, LTR), promoting both paused polymerases and increased efficiency of CRISPR/Cas9 editing in infected cells. This implies that gene editing may be best performed under a repressed transcriptional state. CONCLUSIONS: Collectively, our results indicate that F07#13, which can terminate RNA Polymerase II at distinct sites, can generate scaffold RNAs, which may assemble into specific sets of "RNA Machines" that contribute to gene regulation. It remains to be seen whether these effects can also be seen in various clades that have varying promoter strength, mutant LTRs, and in patient samples.

Comparison of Postoperative Analgesia in Patients Undergoing Ileostomy Closure with and Without Dual Transversus Abdominis Plane (TAP) Block: A Randomized Controlled Trial.

BACKGROUND AND AIMS: Multimodal analgesia comprising opioid, paracetamol, and non-steroidal anti-inflammatory drugs is used for managing postoperative surgical pain after ileostomy closure (IC). We investigated the efficacy of unilateral dual transversus abdominis plane (TAP) block to reduce morphine consumption in the first 24 hours along with a reduction in visual analogue score for pain and in postoperative nausea/vomiting. METHODS: This was a single-center, investigator-initiated, prospective, parallel-group, placebo-controlled randomized study involving patients undergoing IC under general anesthesia. We recruited 55 patients in two groups: 28 in a TAP group and 27 in a placebo group. The TAP group patients received 30 mL of 0.375% bupivacaine: 15 mL by a posterior TAP approach and 15 mL by a subcostal approach using ultrasonography. Patients in the placebo group received 30 mL normal saline (placebo) using the same approaches. Blocks were administered at the end of surgery before extubation. To monitor for the primary outcome-24-hour morphine consumption for both groups-patients were transferred to a high-dependency unit. The secondary outcome was to compare postoperative nausea/vomiting in both groups. RESULTS: The demographic data, gender distribution, ASA physical status, duration of surgery, and time of first morphine dose was comparable in both groups. The 24-hour morphine consumption was 3.29±2.78 mg and 9.23±2.94 mg for the TAP and placebo groups, respectively, which was statistically significant (P=0.001). CONCLUSION: Dual TAP block reduces opioid consumption in the first 24 hours after an IC and can facilitate early recovery with less adverse effects seen than with opioids and NSAIDs.

An Observational Study for Knowing the Compliance of Patients Scheduled for Major Abdominal and Thoracic Cancer Surgeries in a Single Specialty Center.

BACKGROUND: Peri-operative incentive spirometry (IS) helps in improving pulmonary function, facilitates sputum clearance and prevents unwanted postoperative pulmonary complications after major abdominal and thoracic surgery. In our hospital, all patients are instructed to practice IS before abdominal and thoracic surgeries so that they can perform it in the postoperative period effectively. However, many patients do not follow our advice. A few unfortunate patients land up with pulmonary complications as it becomes difficult to train them after surgery. AIMS: To determine the compliance rate of patients who were instructed to perform incentive spirometry preoperatively. STUDY DESIGN AND SETTINGS: Observational, single arm study in a single speciality centre. MATERIALS AND METHODS: After approval from hospital ethics committee the study was registered with Clinical Trials Registry of India (CTRI). 100 patients posted for major abdominal or thoracic cancer surgery were enrolled in the study. They were instructed to perform incentive spirometry(IS) in front of relatives, an information leaflet was provided to them and the spirometry effort was noted in 'ml'. The effort was crossed checked on the day of surgery. Patients performing IS correctly with effort more or equal to that noted earlier were labelled as compliant. Others were labelled as non-compliant. The reason of non-compliance was to be determined using a questionnaire meant for patient and the accompanying family member. RESULTS: Out of 100, 26 patients were found to be non-compliant out of which 10 were males and 16 were female patients. 15 patients did not understand the instructions properly, 8 patients did not get enough time to practice, family members of 10 patients could not help the patient in performing and understanding IS, family members of 8 patients did not have adequate time for the patient. CONCLUSION: A non-compliance rate of 26% could be because patients and family members did not understand the seriousness of preoperative IS in spite of explaining and giving an information leaflet. The surgeries planned were major ones which require arrangement of finances, abstinence from work and other social issues like not having anybody at home with other family members, location of hospital far from the place they live. Involving respiratory therapist and nursing staff early during pre-anaesthesia check up could help in better understanding of the patient and family regarding benefits of IS.

Exosomes from HIV-1-infected Cells Stimulate Production of Pro-inflammatory Cytokines through Trans-activating Response (TAR) RNA.

HIV-1 infection results in a chronic illness because long-term highly active antiretroviral therapy can lower viral titers to an undetectable level. However, discontinuation of therapy rapidly increases virus burden. Moreover, patients under highly active antiretroviral therapy frequently develop various metabolic disorders, neurocognitive abnormalities, and cardiovascular diseases. We have previously shown that exosomes containing trans-activating response (TAR) element RNA enhance susceptibility of undifferentiated naive cells to HIV-1 infection. This study indicates that exosomes from HIV-1-infected primary cells are highly abundant with TAR RNA as detected by RT-real time PCR. Interestingly, up to a million copies of TAR RNA/µl were also detected in the serum from HIV-1-infected humanized mice suggesting that TAR RNA may be stable in vivo. Incubation of exosomes from HIV-1-infected cells with primary macrophages resulted in a dramatic increase of proinflammatory cytokines, IL-6 and TNF-ß, indicating that exosomes containing TAR RNA could play a direct role in control of cytokine gene expression. The intact TAR molecule was able to bind to PKR and TLR3 effectively, whereas the 5' and 3' stems (TAR microRNAs) bound best to TLR7 and -8 and none to PKR. Binding of TAR to PKR did not result in its phosphorylation, and therefore, TAR may be a dominant negative decoy molecule in cells. The TLR binding through either TAR RNA or TAR microRNA potentially can activate the NF-κB pathway and regulate cytokine expression. Collectively, these results imply that exosomes containing TAR RNA could directly affect the proinflammatory cytokine gene expression and may explain a possible mechanism of inflammation observed in HIV-1-infected patients under cART.

Impact of Infectious Diseases Team Consultation on Antimicrobial Use, Length of Stay and Mortality.

BACKGROUND: Infectious disease (ID) clinicians and multidisciplinary teams may have a beneficial impact on patient outcomes. This study was conducted to determine the impact of dedicated ID team rounding in an adult noncardiac intensive care unit (ICU) on antimicrobial costs, length of stay and mortality. METHODS: The authors instituted dedicated ICU ID team rounds at a large tertiary care hospital ICU ("intervention"), with the ID team conducting rounds in the ICU every weekday. The authors compared the cost of antimicrobial agents, total hospital and ICU length of stay and inpatient mortality for the 6-month period before and after institution of these rounds between those seen versus those not seen by the ID team. RESULTS: Among 386 patients analyzed, 206 were admitted in the preintervention and 180 in the postintervention period. Among those seen by the ID team, there was an 18% decrease in total antimicrobial cost (P < 0.0001), 40% decrease in ICU length of stay (P = 0.1), 33% decrease in overall hospital length of stay (P = 0.03) and 34% decrease in mortality (0.04) from preintervention to postintervention period. Among those not seen by ID, there was a 39% decrease in cost among those not seen by ID (P < 0.0001), but length of ICU or hospital stay and mortality were not significantly different. CONCLUSIONS: Institution of dedicated ID team rounding in the ICU leads to substantial decreases in antimicrobial costs, hospital length of stay and inpatient mortality among those patients seen by the team.

Therapeutic doses of irradiation activate viral transcription and induce apoptosis in HIV-1 infected cells.

The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4(+) T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4(+) T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4(+) T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the "Shock and Kill" strategy for latently HIV-1 infected cells.

Human Mesiodistal Tooth Width Measurements and Comparison with Dental Cast in a Bangladeshi Population.

AIM: This analysis was aimed to determine the mesiodistal tooth width of human teeth and to compare with the measurements on plaster model in a Bangladeshi population. MATERIALS AND METHODS: The samples of 2,892 teeth of Bangladeshi subjects were collected for this purpose. This article presents mesiodistal tooth width measurements made on all types of teeth and compares with the mesiodistal tooth width measurements of dental cast collected from Bangladeshi subjects between the ages of 18 and 24 years. The mesiodistal dimension was recorded, involving the maximum mesiodistal dimension of each tooth when measurement was rendered parallel to the occlusal and labial surfaces. Descriptive and comparative statistics were applied. RESULTS: The mean, standard deviation and 95% confidence interval of mesiodistal tooth width measurements were determined and have been with the mesiodistal tooth width measurements of dent al cast. Significant differences have been observed between mesiodistal tooth size of direct measurement on tooth (DMT) and measurement on plaster model (MPM) for the maxillary first molar (p < 0.001) and mandibular incisors to first premolar (p < 0.001). CONCLUSION: These data should prove to be helpful to the practitioner for performing successful orthodontic treatment in Bangladeshi population. CLINICAL SIGNIFICANCE: Direct measurement of mesiodistal tooth width and individual variation of maxillary and mandibular permanent central incisor to first molar of the Bangladeshi individuals showed some distinguishable features, which will certainly help an orthodontist for diagnosis and treatment plan of an orthodontic case.

Role of Bruton's tyrosine kinase inhibitors in HIV-1-infected cells.

Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high-throughput proteomic assays, we have previously identified Bruton's tyrosine kinase (BTK) as a host protein that was uniquely upregulated in the plasma membrane of human immunodeficiency virus (HIV-1)-infected T cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant upregulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells; however, new BTK protein complexes were identified and distributed in both high molecular weight (∼600 kDa) and a small molecular weight complex (∼60-120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1-infected cells using small interfering RNA (siRNA) resulted in selective death of infected, but not uninfected, cells. Using BTK-specific antibody and small-molecule inhibitors including LFM-A13 and a FDA-approved compound, ibrutinib (PCI-32765), we have found that HIV-1-infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1-infected cells are sensitive to treatments targeting BTK expressed in infected cells.

Human T-lymphotropic virus type 1-infected cells secrete exosomes that contain Tax protein.

Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. The HTLV-1 transactivator protein Tax controls many critical cellular pathways, including host cell DNA damage response mechanisms, cell cycle progression, and apoptosis. Extracellular vesicles called exosomes play critical roles during pathogenic viral infections as delivery vehicles for host and viral components, including proteins, mRNA, and microRNA. We hypothesized that exosomes derived from HTLV-1-infected cells contain unique host and viral proteins that may contribute to HTLV-1-induced pathogenesis. We found exosomes derived from infected cells to contain Tax protein and proinflammatory mediators as well as viral mRNA transcripts, including Tax, HBZ, and Env. Furthermore, we observed that exosomes released from HTLV-1-infected Tax-expressing cells contributed to enhanced survival of exosome-recipient cells when treated with Fas antibody. This survival was cFLIP-dependent, with Tax showing induction of NF-κB in exosome-recipient cells. Finally, IL-2-dependent CTLL-2 cells that received Tax-containing exosomes were protected from apoptosis through activation of AKT. Similar experiments with primary cultures showed protection and survival of peripheral blood mononuclear cells even in the absence of phytohemagglutinin/IL-2. Surviving cells contained more phosphorylated Rb, consistent with the role of Tax in regulation of the cell cycle. Collectively, these results suggest that exosomes may play an important role in extracellular delivery of functional HTLV-1 proteins and mRNA to recipient cells.

The use of Nanotrap particles technology in capturing HIV-1 virions and viral proteins from infected cells.

HIV-1 infection results in a chronic but incurable illness since long-term HAART can keep the virus to an undetectable level. However, discontinuation of therapy rapidly increases viral burden. Moreover, patients under HAART frequently develop various metabolic disorders and HIV-associated neuronal disease. Today, the main challenge of HIV-1 research is the elimination of the residual virus in infected individuals. The current HIV-1 diagnostics are largely comprised of serological and nucleic acid based technologies. Our goal is to integrate the nanotrap technology into a standard research tool that will allow sensitive detection of HIV-1 infection. This study demonstrates that majority of HIV-1 virions in culture supernatants and Tat/Nef proteins spiked in culture medium can be captured by nanotrap particles. To determine the binding affinities of different baits, we incubated target molecules with nanotrap particles at room temperature. After short sequestration, materials were either eluted or remained attached to nanotrap particles prior to analysis. The unique affinity baits of nanotrap particles preferentially bound HIV-1 materials while excluded albumin. A high level capture of Tat or Tat peptide by NT082 and NT084 particles was measured by western blot (WB). Intracellular Nef protein was captured by NT080, while membrane-associated Nef was captured by NT086 and also detected by WB. Selective capture of HIV-1 particles by NT073 and NT086 was measured by reverse transcriptase assay, while capture of infectious HIV-1 by these nanoparticles was demonstrated by functional transactivation in TZM-bl cells. We also demonstrated specific capture of HIV-1 particles and exosomes-containing TAR-RNA in patients' serum by NT086 and NT082 particles, respectively, using specific qRT-PCR. Collectively, our data indicate that certain types of nanotrap particles selectively capture specific HIV-1 molecules, and we propose to use this technology as a platform to enhance HIV-1 detection by concentrating viral proteins and infectious virions from infected samples.

Exosomes and their role in CNS viral infections.

Exosomes are small membrane-bound vesicles that carry biological macromolecules from the site of production to target sites either in the microenvironment or at distant sites away from the origin. Exosomal content of cells varies with the cell type that produces them as well as environmental factors that alter the normal state of the cell such as viral infection. Human DNA and RNA viruses alter the composition of host proteins as well as incorporate their own viral proteins and other cargo into the secreted exosomes. While numerous viruses can infect various cell types of the CNS and elicit damaging neuropathologies, few have been studied for their exosomal composition, content, and function on recipient cells. Therefore, there is a pressing need to understand how DNA and RNA viral infections in CNS control exosomal release. Some of the more recent studies including HIV-1, HTLV-1, and EBV-infected B cells indicate that exosomes from these infections contain viral miRNAs, viral transactivators, and a host of cytokines that can control the course of infection. Finally, because exosomes can serve as vehicles for the cellular delivery of proteins and RNA and given that the blood-brain barrier is a formidable challenge in delivering therapeutics to the brain, exosomes may be able to serve as ideal vehicles to deliver protein or RNA-based therapeutics to the brain.

Contraceptive choice and acceptability: the future for STI risk in Kelantan, Malaysia.

More than 150 million women become pregnant in developing countries annually and an estimated 287,000 die from pregnancy-related causes. Contraception is vital to prevent unnecessary maternal deaths, as well as sexually transmitted infections. The objective of this study was to investigate preferred contraceptive methods and the factors that influence contraceptive choice among women in Kelantan, Malaysia. A cross-sectional study using interview-based questionnaires was conducted, during July and August 2009, in local family planning clinics in Kelantan. The questionnaire was administered to adult women (age 20-50). Prevalence of unplanned pregnancies was high (48%). Contraceptive preference was Depo contraceptive injection (32%), oral contraceptive pills (27%), intrauterine devices (15%) and contraceptive implants (12%); 9% used condoms. Only 2% used contraception to protect against sexually transmitted infections or HIV/AIDS. Younger women (OR 0.90; 95% CI 0.807-0.993) were more likely to use contraception. In conclusion, non-interrupted contraceptive methods were preferred. More than 60% would stop using contraception if it interrupted intercourse. From both a public health and infectious disease perspective, this is extremely worrying.

Novel neuroprotective GSK-3ß inhibitor restricts Tat-mediated HIV-1 replication.

The implementation of new antiretroviral therapies targeting transcription of early viral proteins in postintegrated HIV-1 can aid in overcoming current therapy limitations. Using high-throughput screening assays, we have previously described a novel Tat-dependent HIV-1 transcriptional inhibitor named 6-bromoindirubin-3'-oxime (6BIO). The screening of 6BIO derivatives yielded unique compounds that show potent inhibition of HIV-1 transcription. We have identified a second-generation derivative called 18BIOder as an inhibitor of HIV-1 Tat-dependent transcription in TZM-bl cells and a potent inhibitor of GSK-3ß kinase in vitro. Structurally, 18BIOder is half the molecular weight and structure of its parental compound, 6BIO. More importantly, we also have found a different GSK-3ß complex present only in HIV-1-infected cells. 18BIOder preferentially inhibits this novel kinase complex from infected cells at nanomolar concentrations. Finally, we observed that neuronal cultures treated with Tat protein are protected from Tat-mediated cytotoxicity when treated with 18BIOder. Overall, our data suggest that HIV-1 Tat-dependent transcription is sensitive to small-molecule inhibition of GSK-3ß.

Transmission of chimeric HIV by mating in conventional mice: prevention by pre-exposure antiretroviral therapy and reduced susceptibility during estrus.

Heterosexual transmission accounts for the majority of new human immunodeficiency virus (HIV) cases worldwide. The current approach to investigate HIV heterosexual transmission in animals involves application of virus stock to the vaginal surface, a method that does not reproduce the physiological conditions of vaginal intercourse that influence the rate of transmission. We have previously described efficient infection of conventional mice using EcoHIV/NL4-3 and EcoHIV/NDK, chimeric HIV molecular clones constructed to express all HIV structural and regulatory genes except envelope, which is replaced by a rodent-tropic envelope gene. Here we investigated whether EcoHIV/NDK-infected male mice transmit virus to females during coitus, and the sensitivity of this transmission to HIV pre-exposure prophylaxis and the estrus state. Our general approach was to allow mating between EcoHIV/NDK-infected male mice and uninfected females for 1-7 nights. At 1-6 weeks after mating, mice were euthanized and virus burdens were measured by quantitative PCR (qPCR) amplification of HIV RNA or DNA in peritoneal macrophages, inguinal lymph node cells, spleen cells or vas deferens, or by ELISA for antibodies to HIV Gag. We found that 70-100% of female mice mated to EcoHIV/NDK-infected males acquired infection. Pericoital treatment of females with either 2',3'-dideoxcytidine (ddC) or tenofovir largely prevented their EcoHIV/NDK infection by mating (P<0.05 and P<0.003, respectively). In males, T cells were dispensable for virus transmission. The rate of EcoHIV/NDK sexual transmission to females in estrus declined sharply (P=0.003) but their infection by injection was unaffected, indicating that the local environment in the female reproductive tract influences susceptibility to HIV. We conclude that this system of EcoHIV/NDK transmission during mouse mating reproduces key features of heterosexual transmission of HIV in humans and can be used to investigate its biology and control.

Humanized mouse models of HIV-1 latency.

The existence of long-lasting cellular reservoirs of HIV-1 is one of the major hurdles in developing effective anti-retroviral therapies. These latently infected cells and tissues efficiently evade immune responses and remain dormant until activated, upon which they can generate a productive HIV-1 infection. This classic scenario of viral latency becomes even more difficult to study and model due to the extreme complexity of translating in vivo virus-cell interactions into a controlled in vitro system. The recent developments and constant improvements upon hematopoietic engraftment of human cells and tissues onto recipient immunocompromised murine scaffolds have made it possible to model complex human innate and adaptive immune responses in a small animal model. Specifically, HIV-1 infection has been successfully modeled in these humanized mice to mimic transmission, pathogenesis, host immune responses, and treatment. Here, we review the complexities surrounding modeling HIV-1 latency in vitro and in vivo and highlight the most recent humanized mouse models that support retroviral infection.