bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Short Hairpin RNA Driven by Polymerase II Suppresses both Wild-Type and Lamivudine-Resistant Hepatitis B Virus Strains
Authors: Ren Guang-Li , Fang Ying , Ma Heng-Hao , Lei Ying-Feng , Wang Dan , Xu Man-Chun , Wang Ping-Zhong , Huang Chang-Xing , Nie Qing-He , Sun Yong-Tao , Bai Xue-Fan 
Published: April 2022

Background Chronic infection with hepatitis B virus (HBV) is widespread because of the limited availability of therapeutic treatments. Although previous reports have suggested that RNA interference has promise as a treatment for HBV infection, further studies of long-term and off-target drug effects on HBV, especially on drug-resistant strains of HBV, are needed. Therefore, seven vectors that express short hairpin RNAs (shRNAs), driven by the polymerase II promoter, pSilencer4.1/HBV, were constructed to target open reading frames (ORFs) of the HBV C and S genes from wild-type and drug-resistant strains. Treatment efficiency was also assessed. Methods The pSilencer4.1/HBV vectors were investigated in HepG2.2.15 cells and transgenic mice that consistently produce wild-type HBV. Additionally, vectors that produce a lamivudine-resistant strain of HBV were developed and cotransfected, along with pSilencer/HBV, into both HepG2 cells and mice. The effects of polymerase-II-driven pSilencer4.1/HBV were compared with those of polymerase-III-driven pSilencer3.1/HBV at both the gene and protein level. Results pSilencer4.1/HBV inhibited the expression of viral protein, DNA and HBV subtype ayw mRNA in both HepG2.2.15 cells and transgenic mice. Toxicity, as well as off-target effects, did not occur after a short- to medium-term examination. Moreover, an HBV strain resistant to lamivudine, subtype adr, was suppressed by shRNA in both HepG2 cells and mice. In contrast to polymerase III, vectors that used polymerase II could drive efficient silencing without off-target effects. Conclusions Silencing by shRNA dramatically inhibited HBV expression and replication regardless of strain type. ShRNA could therefore be a promising treatment for HBV infection.
Mitochondrial Toxicity of Indinavir, Stavudine and Zidovudine Involves Multiple Cellular Targets in white and brown adipocytes
Authors: Viengchareun Say , Caron Martine , Auclair Martine , Kim Min Ji , Frachon Paule , Capeau Jacqueline , Lombès Marc , Lombès Anne 
Published: April 2022

Objective To evaluate the mechanisms of mitochondrial toxicity associated with antiretroviral treatment. Methods 3T3–F442A white and T37i brown adipocytes were exposed to stavudine (10 μM), zidovudine (1 μM) and indinavir (10 μM), alone or in combination. Adipocyte fat content was measured with Oil Red O staining. Quantification of mRNA levels and of mitochondrial DNA content used PCR-based techniques. Mitochondrial activities were evaluated with respiration, ATP synthesis and spectrophotometric assays. Mitochondrial mass was assessed by the fluorescent probe MitoTracker Red. Results In both cell types, all the treatments induced a severe defect of adipogenesis (low lipid content and decreased markers of adipogenic maturation: peroxisome proliferator-activated receptor [PPAR]γ2 and aP2 but also uncoupling protein 1 in brown adipocytes) as well as altered mitochondrial function (decreased respiration rate and increased mitochondrial mass). Drug combination did not give additional toxicity. Brown adipocytes appeared more affected than white adipocytes (lower respiration rate and decreased ATP production). The mechanisms of mitochondrial toxicity differed with the drug and the cell type. Only stavudine induced severe mitochondrial DNA depletion in both cell types. With all the treatments, white adipocytes showed a decrease in the expression of mitochondrial and nuclear-DNA-encoded respiratory chain subunits (cytochrome c oxidase [CytOx]2 and CytOx4), whereas brown adipocytes maintained normal expression in accordance with their increase of the transcriptional factors of mitochondrial biogenesis nuclear respiratory factor 1 and PPARγ coactivator (PGC)1-related cofactor PRC, but not PGC1α. Conclusion Our results provide evidence for dissociation between mitochondrial activity, transcription and mitochondrial DNA content, highlighting the complexity of mitochondrial toxicity, which affects multiple cellular targets.
Safety and Immunogenicity from a Phase I Trial of Inactivated Severe Acute Respiratory Syndrome Coronavirus Vaccine
Authors: Lin Jiang-Tao , Zhang Jian-San , Su Nan , Xu Jian-Guo , Wang Nan , Chen Jiang-Ting , Chen Xin , Liu Yu-Xuan , Gao Hong , Jia Yu-Ping , Liu Yan , Sun Rui-Hua , Wang Xu , Yu Dong-Zheng , Hai Rong , Gao Qiang , Ning Ye , Wang Hong-Xia , Li Ma-Chao , Kan Biao , Dong Guan-Mu , An Qi , Wang Ying-Qun , Han Jun , Qin Chuan , Yin Wei-Dong , Dong Xiao-Ping 
Published: April 2022

Background Emergence of severe acute respiratory syndrome (SARS) from the winter of 2002 to the spring of 2003 has caused a serious threat to public health. Methods To evaluate the safety and immunogenicity of the inactivated SARS coronavirus (SARS-CoV) vaccine, 36 subjects received two doses of 16 SARS-CoV units (SU) or 32 SU inactivated SARS-CoV vaccine, or placebo control. Results On day 42, the seroconversion reached 100% for both vaccine groups. On day 56, 100% of participants in the group receiving 16 SU and 91.1% in the group receiving 32 SU had seroconverted. The geometric mean titre of neutralizing antibody peaked 2 weeks after the second vaccination, but decreased 4 weeks later. Conclusion The inactivated vaccine was safe and well tolerated and can elicit SARS-CoV-specific neutralizing antibodies.
Transmission of Drug-Resistant HIV-1 from an Infected Individual to a Caregiver
Authors: Brumme Chanson J , Harrigan P Richard , Preston Emma C , Dong Winnie WY , Wynhoven Brian , Murphy Carol , Montaner Julio SG 
Published: April 2022

Objective To describe a suspected case of intrafamilial transmission of drug-resistant HIV-1 from an infected individual to his caregiver. Methods HIV-1 protease, reverse transcriptase, nef and gp41 DNA sequences were determined from plasma samples after RNA extraction and nested RT-PCR. Phylogenetic trees were generated using neighbour-joining methods. Results HIV-1 infection was diagnosed in an individual (index) following the death of her HIV-infected adopted son (source). The index case cared for her son in the 9 months prior to his death. No obvious instances of contact with bodily secretions or other traditional risk factors for HIV transmission were identified, although the index case had mild eczema. At time of death, the source case's HIV plasma viral load was >1,000,000 HIV copies/ml. Genotyping of the protease and reverse transcriptase of both the source and index samples revealed similar drug-resistance mutations despite the index case being antiretroviral-naive. Both source and index V3 genotypes were consistent with syncytium-inducing virus. The mean pairwise amino acid identity between the source and index samples was 97.0%, 99.2%, 92.6% and 94.6% in protease, reverse transcriptase, nef and gp41, respectively. The source and index sequences clustered together on phylogenetic trees when compared with 50 randomly selected sequences from British Columbia. Conclusion Although exceptionally rare, our case demonstrates transmission of drug-resistant HIV-1 from an infected individual to his caregiver in the absence of traditional risk factors. It should be noted that the source had a very high viral load during the terminal phase of his illness.
Mitochondrial Toxicity of Tenofovir, Emtricitabine and Abacavir Alone and in Combination with Additional Nucleoside Reverse Transcriptase Inhibitors
Authors: Venhoff Nils , Setzer Bernhard , Melkaoui Kerstina , Walker Ulrich A 
Published: April 2022

Background Some nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) combinations cause additive or synergistic interactions in vitro and in vivo. Methods We evaluated the mitochondrial toxicity of tenofovir (TFV), emtricitabine (FTC) and abacavir as carbovir (CBV) alone, with each other, and in combination with additional NRTIs. HepG2 human hepatoma cells were incubated with TFV, FTC, CBV, didanosine (ddI), stavudine (d4T), lamivudine (3TC) and zidovudine (AZT) at concentrations equivalent to 1 and 10x clinical steady-state peak plasma levels (Cmax). NRTIs were also used in double and triple combinations. Cell growth, lactate production, intracellular lipids, mtDNA and the mtDNA-encoded respiratory chain subunit II of cytochrome c oxidase (COXII) were monitored for 25 days. Results TFV and 3TC had no or minimal toxicity. FTC moderately reduced hepatocyte proliferation independent of effects on mtDNA. ddI and d4T induced a time- and dose-dependent loss of mtDNA and COXII, decreased cell growth and increased levels of lactate and intracellular lipids. CBV and AZT strongly impaired hepatocyte proliferation and increased lactate and lipid production, but did not induce mtDNA depletion. The dual combination of TFV plus 3TC had only minimal toxicity; TFV plus FTC slightly reduced cell proliferation without affecting mitochondrial parameters. All other combinations exhibited more pronounced adverse effects on mitochondrial endpoints. Toxic effects on mitochondrial parameters were observed in all combinations with ddI, d4T, AZT or CBV. TFV and 3TC both attenuated ddI-related cytotoxicity, but worsened the effects of CBV and AZT. Conclusions The data demonstrate unpredicted interactions between NRTIs with respect to toxicological endpoints and provide an argument against the liberal use of NRTI cocktails without first obtaining data from clinical trials.
Induction of Regulatory T-Cells and Interleukin-10-Producing Cells in Non-Responders to Pegylated Interferon-α Therapy for Chronic Hepatitis B
Authors: Sprengers Dave , Stoop Jeroen N , Binda Rekha S , Kusters Johannes G , Haagmans Bart L , Carotenuto Patrizia , Artsen Andre , Van Der Molen Renate G , Janssen Harry LA 
Published: April 2022

Background Treatment with interferon-α (IFN-α) leads to a response in only a minority of patients with chronic hepatitis B virus (HBV) infection, but the reasons for this are poorly understood. It was recently shown that in patients with chronic HBV infection, CD4+CD25+ regulatory T-cells (Treg) can suppress the HBV-specific immune response. We aimed to investigate whether in non-responders to IFN-α therapy Treg contribute to treatment failure by downregulating the HBV-specific T-cell responses. Patients and methods Fourteen patients positive for hepatitis B e antigen received pegylated IFN-α monotherapy for 52 weeks and were followed for 26 weeks. Results Compared with non-responders, responders displayed an increased HBV-specific T-helper cell proliferation. At the start of treatment there was no difference in the frequencies of CD4+CD25+ Treg between responders and non-responders. During therapy, the frequency of CD4+CD25+ Treg increased in non-responders, but not in responders. In contrast to the responders, the non-responders showed a significant increase in the frequency of interleukin-10-producing cells. Treg depletion resulted in increased proliferation capacity, but did not affect the frequency of interleukin-10-producing cells measured during the course of the treatment. Conclusion This study indicates that Treg might have an important role in HBV persistence during and after pegylated IFN-α therapy.
Pharmacokinetics and Pharmacodynamics of Combined use of Lopinavir/Ritonavir and Rosuvastatin in HIV-Infected Patients
Authors: Van Der Lee Manon , Sankatsing Raaj , Schippers Emile , Vogel Martin , Fätkenheuer Gerd , Van Der Ven Andre , Kroon Frank , Rockstroh Jürgen , Wyen Christoph , Bäumer Anselm , De Groot Eric , Koopmans Peter , Stroes Erik , Reiss Peter , Burger David 
Published: April 2022

Background Lopinavir/ritonavir-containing antiretro-viral therapy can cause hyperlipidaemia. However, most statins are contraindicated due to drug-drug interactions. Rosuvastatin undergoes minimal metabolism by CYP450, so no CYP450-based interaction with lopinavir/ritonavir is expected. This study explored the lipid-lowering effect of rosuvastatin and assessed the effect of lopinavir/ritonavir on the pharmacokinetics of rosuvastatin and vice versa. Methods HIV-infected patients on lopinavir/ritonavir (viral load <400 copies/ml) with total cholesterol (TC) >6.2 mmol/l were treated with rosuvastatin for 12 weeks, starting on 10 mg once daily. If fasting target values (TC<5.0 mmol/l, high-density lipoprotein-cholesterol >1.0 mmol/l, low-density lipoprotein-cholesterol [LDL-c] <2.6 mmol/l and triglycerides <2.0 mmol/l) were not reached, rosuvastatin was escalated to 20 mg or 40 mg at week 4 and 8, respectively. Plasma lopinavir/ritonavir trough levels (Cmin) were determined at week 0, 4, 8 and 12 and rosuvastatin Cmin, at week 4, 8 and 12. Results Twenty-two patients completed the study. Mean reductions in TC and LDL-c from baseline to week 4 (on rosuvastatin 10 mg once a day) were 27.6% and 31.8%, respectively. Lopinavir/ritonavir concentrations were not influenced by rosuvastatin ( P=0.44 and 0.26, repeated-measures analysis). Median (interquartile range) rosuvastatin Cmin for 10 mg, 20 mg and 40 mg once daily were 0.97 (0.70–1.5), 2.5 (1.3–3.3) and 5.5 (3.3–8.8) ng/ml, respectively. Conclusions Rosuvastatin appeared to be an effective statin in hyperlipidaemic HIV-infected patients. Lopinavir/ritonavir levels were not affected by rosuvastatin, but rosuvastatin levels unexpectedly appeared to be increased 1.6-fold compared with data from healthy volunteers. Until safety and efficacy have been confirmed in larger studies, the combination of rosuvastatin and lopinavir/ritonavir should be used with caution.
Decreasing CD4+ T-cell Count During Suppressed or Low-Level Viraemia in Patients with HIV Infection
Authors: Anderson Albert ML , Kosinski Andrzej S , Bartlett John A 
Published: April 2022

Background Suboptimal improvement in CD4+ T-cell count is not uncommon in HIV-infected patients with suppressed plasma HIV RNA levels, and a decrease in CD4+T-cell count in patients with suppressed or low-level viraemia has been observed. Methods Our objectives were to identify the prevalence of decreasing CD4+ T-cell counts during suppressed or low-level viraemia, to determine the frequency of clinical events during and immediately after such decreases, and to examine for associations with individual variables. A matched case-control study was undertaken using the Duke Infectious Diseases Clinic database ( n=3,949). Cases had at least two consecutive significant decreases in either CD4+ absolute count or CD4+ percentage, while also having plasma HIV RNA levels <1,000 copies/ml. Results The prevalence of decreasing CD4+ T-cell counts during suppressed or low-level viraemia was 1.22%. Only three HIV-associated clinical events occurred. The majority of cases had an increase in the CD4+ T-cell count immediately following the study period. The use of either zidovudine or stavudine was weakly associated with decreasing CD4+ T-cell counts in a multivariable analysis, but this association was not present in cases with only a decrease in CD4+ T-cell percentage. Conclusions Decreasing CD4+ T-cell counts during suppressed or low-level viraemia are rare, typically transient, and not associated with an increase in HIV-associated clinical events.
Prospective Cohort Study of HIV Post-Exposure Prophylaxis for Sexual Assault Survivors
Authors: Loutfy Mona Rafik , Macdonald Sheila , Myhr Terri , Husson Heather , Du Mont Janice , Balla Shannon , Antoniou Tony , Rachlis Anita 
Published: April 2022

Background There is a lack of standardized programs for HIV counselling and post-exposure prophylaxis (PEP) in the setting of sexual assault. Methods We conducted an 18-month prospective cohort study assessing universal HIV counselling for all sexual assault survivors presenting to 18 Ontario Sexual Assault Treatment Centres. HIV PEP was universally offered to those at risk of HIV infection (high risk or unknown risk) presenting ≤72 h after the assault, using Combivir® one pill and Kaletra® three capsules twice a day for 28 days. Those who accepted HIV PEP were monitored via a schedule of frequent follow ups. The primary outcomes were acceptance and completion rates, and their predictors were determined using multivariable logistic regression. Adverse events (AE) were categorized using a standardized toxicity grading system. Results Of the 900 evaluable participants eligible for PEP, 798 (69 at high risk and 729 at unknown risk) were offered treatment. Acceptance rates were 66.7% ( n=46) and 41.3% ( n=301) for participants at high risk and unknown risk, respectively. Participants at high risk were 2.2 times more likely to accept PEP than those at unknown risk (adjusted odds ratio 2.2; 95% confidence interval 1.2–4.0; P=0.01). Overall, 23.9% high-risk ( n=11) and 33.2% unknown-risk participants ( n=100) completed PEP ( P=0.20). Predictors of acceptance and completion included assault by a stranger and participant anxiety. AEs were common, with 77.1% of participants reporting grade 2–4 symptoms. Conclusion A province-wide standardized program of universal HIV counselling and offering of PEP to sexual assault survivors with frequent follow up was successfully implemented and feasible.
Passive Immunization Protects Cynomolgus Macaques against Puumala Hantavirus Challenge
Authors: Klingström Jonas , Stoltz Malin , Hardestam Jonas , Ahlm Clas , Lundkvist Åke 
Published: April 2022

Background Hantaviruses cause two severe and often fatal human diseases: haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Presently, there is no effective prevention available for HFRS or HPS. Here, we studied the effect of passive immunization on the course of infection in cynomolgus macaques challenged with wild-type Puumala hantavirus (PUUV-wt). Methods A pool of serum drawn from previously PUUV-wt-infected monkeys was used for immunization; a pool of serum from the same monkeys that was obtained before infection was used as a control. Immunizations were administered 3 days before and 15 days after challenge with PUUV-wt. After challenge, monkeys were sampled once a week and analysed for PUUV-infection markers. Results All three monkeys treated with non-immune serum became positive for PUUV RNA in plasma and showed PUUV nucleocapsid-specific immunoglobin M (IgM) responses after challenge. In contrast, no PUUV RNA or anti-PUUV-specific IgM response was detected in the three passively immunized monkeys. As seen in PUUV-infected humans, the control monkeys showed a marked decrease in the amount of platelets and increased levels of creatinine, interleukin (IL)-6, IL-10, and tumour necrosis factor (TNF) after inoculation. In contrast, no marked changes in the amount of platelets were observed in the immunized monkeys and they did not show increased levels of creatinine, IL-6, IL-10 and TNF after virus challenge. Conclusion The results show that passive immunization in monkeys, using serum from previously hantavirus-infected monkeys, can induce sterile protection and protect against pathogenesis. Convalescent-phase antibodies may represent a potential therapy that can induce immediate protection against HFRS and HPS.
Characterization of drug Resistance in Antiretroviral-Treated Patients Infected with HIV-1 CRF02_AG and AGK Subtypes in Mali and Burkina Faso
Authors:   the ATARAO group, Sylla Mohamed , Chamberland Annie , Boileau Catherine , Traoré Hamar A , Ag-Aboubacrine Souleyman , Cissé Mamadou , Koala Samual , Drabo Joseph , Diallo Ismael , Niamba Pascal , Tremblay-Sher Daniel , Machouf Nimâ , Rashed Sélim , Nickle David C , Nguyen Vinh-Kim , Tremblay Cécile L 
Published: April 2022

Background In a multicentred cohort of patients on antiretroviral therapy (ART) in Burkina Faso and Mali, we analysed the prevalence of HIV drug resistance mutations in patients failing a modified directly observed therapy (mDOT) protocol. Methods Patients on ART >6 months and with viral load (VL) >500 copies/ml were enrolled in a mDOT protocol. Genotypic resistance testing was performed on pre- and post-mDOT plasma samples of patients who still had VL >500 copies/ml after mDOT. Results Eight hundred and one patients from seven sites participated in the study. One hundred and thirteen patients (14.1%) had VL >500 copies/ml. Most patients were treated with lamivudine along with zidovudine or stavudine and efavirenz or nevirapine. Genotypes were available for 46 patients. The predominant HIV-1 subtypes were CRF02_AG in 26 (56.5%) and AGK/K/AK in 12 (26.1%) patients. The prevalence of drug resistance mutations by class were as follows for nucleoside reverse transcriptase inhibitors: 184I/V (82.6%), 215Y/F (32.6%), 219E/Q (19.6%), 70R (19.6%), 67N (21.7%), 41L (15.2%) and 151M(2.2%). For non-nucleoside reverse transcriptase inhibitors the prevalence was: 103N (50%) and 181C/I (19.6%). Phylogenetic analysis showed that, although the genetic distances were small among isolates, there was no clustering of a particular subtype in a specific region and that the high prevalence of AGK subtype in our drug-resistant population was not due to a circulating resistant strain. Conclusion Although CRF02_AG is the dominant clade in the Burkina Faso/Mali region, isolates with subtype K reverse transcriptase were frequent in our cohort. Drug resistance mutation pathways in subtype K reverse transcriptase need to be further evaluated in a larger cohort of non-B HIV-infected individuals.
The Risk of Developing Peripheral Neuropathy Induced by Nucleoside Reverse Transcriptase Inhibitors Decreases over Time: Evidence from the Delta Trial
Authors: Arenas-Pinto Alejandro , Bhaskaran Krishnan , Dunn David , Weller Ian VD 
Published: April 2022

Background Peripheral neuropathy (PN) in HIV-infected individuals is thought be due to a toxic effect on mitochondria induced by some nucleoside reverse transcriptase inhibitors (NRTI). Methods A time-to-event analysis was performed using data from the Delta trial to study the incidence of PN in HIV-infected individuals receiving zidovudine (AZT) alone or in combination with didanosine (ddI) or zalcitabine (ddC). In an on-treatment analysis, changes in the incidence of PN by duration of treatment were directly estimated using a flexible parametric survival model. Results A total of 3,195 patients (total follow-up 4,593 person-years) were included in the analysis. AZT+ddC was associated with a higher incidence of PN (6.2 cases/100 person-years) compared with AZT monotherapy (3.0 cases/100 person-years) and AZT+ddI (2.2 cases/100 person-years). The risk of PN peaked around day 90 following randomization (at 8.9 events/100 person-years in the AZT+ddC arm). PN was also associated with age at entry (hazard ratio (HR)=2.35 for those aged 35–44 years compared with <30) and current CD4+ T-cell count (HR=2.27 for CD4+ T-cell counts <150 cell/mm3 compared with >350). Conclusion Our findings challenge the common supposition that PN arises from cumulative exposure to NRTIs. We found that patients who developed PN tended to do so shortly after exposure to antiretroviral therapy. Therefore, our results support the hypothesis of a susceptibility in a subgroup of patients. These results will be of direct interest to those working in resource-limited countries where potentially neurotoxic dideoxynucleosides are still widely used.