SHIV-C109p5 NHP induces rapid disease progression in elderly macaques with extensive GI viral replication

CCR5-tropic simian/human immunodeficiency viruses (SHIV) with clade C transmitted/founder envelopes represent a critical tool for the investigation of HIV experimental vaccines and microbicides in nonhuman primates, although many such isolates lead to spontaneous viral control post infection. Here, we generated a high-titer stock of pathogenic SHIV-C109p5 by serial passage in two rhesus macaques (RM) and tested its virulence in aged monkeys. The co-receptor usage was confirmed before infecting five geriatric rhesus macaques (four female and one male). Plasma viral loads were monitored by reverse transcriptase-quantitative PCR (RT-qPCR), cytokines by multiplex analysis, and biomarkers of gastrointestinal damage by enzyme-linked immunosorbent assay. Antibodies and cell-mediated responses were also measured. Viral dissemination into tissues was determined by RNAscope. Intravenous SHIV-C109p5 infection of aged RMs leads to high plasma viremia and rapid disease progression; rapid decrease in CD4+ T cells, CD4+CD8+ T cells, and plasmacytoid dendritic cells; and wasting necessitating euthanasia between 3 and 12 weeks post infection. Virus-specific cellular immune responses were detected only in the two monkeys that survived 4 weeks post infection. These were Gag-specific TNFα+CD8+, MIP1β+CD4+, Env-specific IFN-γ+CD4+, and CD107a+ T cell responses. Four out of five monkeys had elevated intestinal fatty acid binding protein levels at the viral peak, while regenerating islet-derived protein 3α showed marked increases at later time points in the three animals surviving the longest, suggesting gut antimicrobial peptide production in response to microbial translocation post infection. Plasma levels of monocyte chemoattractant protein-1, interleukin-15, and interleukin-12/23 were also elevated. Viral replication in gut and secondary lymphoid tissues was extensive.IMPORTANCESimian/human immunodeficiency viruses (SHIV) are important reagents to study prevention of virus acquisition in nonhuman primate models of HIV infection, especially those representing transmitted/founder (T/F) viruses. However, many R5-tropic SHIV have limited fitness in vivo leading to many monkeys spontaneously controlling the virus post acute infection. Here, we report the generation of a pathogenic SHIV clade C T/F stock by in vivo passage leading to sustained viral load set points, a necessity to study pathogenicity. Unexpectedly, administration of this SHIV to elderly rhesus macaques led to extensive viral replication and fast disease progression, despite maintenance of a strict R5 tropism. Such age-dependent rapid disease progression had previously been reported for simian immunodeficiency virus but not for R5-tropic SHIV infections.

TGF-β blockade drives a transitional effector phenotype in T cells reversing SIV latency and decreasing SIV reservoirs in vivo

HIV-1 persistence during ART is due to the establishment of long-lived viral reservoirs in resting immune cells. Using an NHP model of barcoded SIVmac239 intravenous infection and therapeutic dosing of anti-TGFBR1 inhibitor galunisertib (LY2157299), we confirm the latency reversal properties of in vivo TGF-β blockade, decrease viral reservoirs and stimulate immune responses. Treatment of eight female, SIV-infected macaques on ART with four 2-weeks cycles of galunisertib leads to viral reactivation as indicated by plasma viral load and immunoPET/CT with a 64Cu-DOTA-F(ab')2-p7D3-probe. Post-galunisertib, lymph nodes, gut and PBMC exhibit lower cell-associated (CA-)SIV DNA and lower intact pro-virus (PBMC). Galunisertib does not lead to systemic increase in inflammatory cytokines. High-dimensional cytometry, bulk, and single-cell (sc)RNAseq reveal a galunisertib-driven shift toward an effector phenotype in T and NK cells characterized by a progressive downregulation in TCF1. In summary, we demonstrate that galunisertib, a clinical stage TGF-β inhibitor, reverses SIV latency and decreases SIV reservoirs by driving T cells toward an effector phenotype, enhancing immune responses in vivo in absence of toxicity.

TGF-β blockade drives a transitional effector phenotype in T cells reversing SIV latency and decreasing SIV reservoirs in vivo

HIV-1 persistence during ART is due to the establishment of long-lived viral reservoirs in resting immune cells. Using an NHP model of barcoded SIVmac239 intravenous infection and therapeutic dosing of the anti-TGFBR1 inhibitor galunisertib (LY2157299), we confirmed the latency reversal properties of in vivo TGF-β blockade, decreased viral reservoirs and stimulated immune responses. Eight SIV-infected macaques on suppressive ART were treated with 4 2-week cycles of galunisertib. ART was discontinued 3 weeks after the last dose, and macaques euthanized 6 weeks after ART-interruption(ATI). One macaque did not rebound, while the remaining rebounded between week 2 and 6 post-ATI. Galunisertib led to viral reactivation as indicated by plasma viral load and immunoPET/CT with the 64Cu-DOTA-F(ab')2-p7D3-probe. Half to 1 Log decrease in cell-associated (CA-)SIV DNA was detected in lymph nodes, gut and PBMC, while intact pro-virus in PBMC decreased by 3-fold. No systemic increase in inflammatory cytokines was observed. High-dimensions cytometry, bulk and single-cell RNAseq revealed a shift toward an effector phenotype in T and NK cells. In summary, we demonstrated that galunisertib, a clinical stage TGFβ inhibitor, reverses SIV latency and decreases SIV reservoirs by driving T cells toward an effector phenotype, enhancing immune responses in vivo in absence of toxicity.

Blockade of TGF-β signaling reactivates HIV-1/SIV reservoirs and immune responses in vivo

TGF-β plays a critical role in maintaining immune cells in a resting state by inhibiting cell activation and proliferation. Resting HIV-1 target cells represent the main cellular reservoir after long-term antiretroviral therapy (ART). We hypothesized that releasing cells from TGF-β-driven signaling would promote latency reversal. To test our hypothesis, we compared HIV-1 latency models with and without TGF-β and a TGF-β type 1 receptor inhibitor, galunisertib. We tested the effect of galunisertib in SIV-infected, ART-treated macaques by monitoring SIV-env expression via PET/CT using the 64Cu-DOTA-F(ab')2 p7D3 probe, along with plasma and tissue viral loads (VLs). Exogenous TGF-β reduced HIV-1 reactivation in U1 and ACH-2 models. Galunisertib increased HIV-1 latency reversal ex vivo and in PBMCs from HIV-1-infected, ART-treated, aviremic donors. In vivo, oral galunisertib promoted increased total standardized uptake values in PET/CT images in gut and lymph nodes of 5 out of 7 aviremic, long-term ART-treated, SIV-infected macaques. This increase correlated with an increase in SIV RNA in the gut. Two of the 7 animals also exhibited increases in plasma VLs. Higher anti-SIV T cell responses and antibody titers were detected after galunisertib treatment. In summary, our data suggest that blocking TGF-β signaling simultaneously increases retroviral reactivation events and enhances anti-SIV immune responses.

Long-term side effects and lingering symptoms post COVID-19 recovery

Since the Coronavirus disease 2019 (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), our understanding regarding the pathophysiology and clinical manifestations of this disease have been improving. However, we still have limited data on long‐term effects and lingering symptoms of post COVID‐19 recovery. Despite predilection of COVID‐19 for lungs, multiple extra‐pulmonary manifestations appear in multiple organs and biological systems and with continued infection and recovery worldwide. It is necessary that clinicians provide patients with previous SARS‐CoV‐2 infection with expectations of long‐term effects during or after recovery from COVID‐19. Herein, we review the long‐term impact of COVID‐19 on different organ systems reported from different clinical studies. Understanding risk factors and signs and symptoms of long‐term consequences after recovery from COVID‐19 will allow for proper follow‐up and management of the disease post recovery.

Oral Vaccination Approaches for Anti-SHIV Immunity

We modified a Sabin Oral Poliovirus Vaccine (OPV) vector to permit secretion of the antigens of interest with the goal of improving anti-HIV Env humoral responses in a SHIV mucosal immunization composed of DNA and recombinant OPVs. We evaluated stimulation of systemic and mucosal cell-mediated and humoral immunity in Rhesus macaques by two regimens, both involving a prime with a SHIVBG505 DNA construct producing non-infectious particles formulated in lipid nanoparticles, administered in the oral cavity, and two different viral vector boostings, administered in the oral cavity and intestinally. Group 1 was boosted with rMVA-SHIVBG505, expressing SIV Gag/Pol and HIVBG505 Env. Group 2 was boosted with a SHIVBG505-OPV vaccine including a non-secreting SIVmac239CA-p6-OPV, expressing Gag CA, NC and p6 proteins, and a HIVBG505C1-V2-OPV, secreting the C1-V2 fragment of HIV EnvBG505, recognized by the broadly neutralizing antibody PG16. A time course analysis of anti-SHIV Gag and Env CD4+ and CD8+ T-cell responses in PBMC and in lymph node, rectal, and vaginal MNC was carried out. Both regimens stimulated significant cell-mediated responses in all compartments, with SHIVBG505-OPV immunization stimulating more significant levels of responses than rMVA- SHIVBG505. Boolean analysis of these responses revealed predominantly monofunctional responses with multifunctional responses also present in all tissues. Stimulation of antibody responses was disappointing in both groups with negative anti-SHIV IgG in plasma, and IgA in salivary, rectal and vaginal secretions being restricted to a few animals. After repeated rectal challenge with SHIVBG505, two Group 1 animals remained uninfected at challenge termination. No significant differences were observed in post-infection viral loads between groups. After the acute phase decline, CD4+ T cell percentages returned to normal levels in vaccinated as well as control animals. However, when compared to controls, vaccinate groups had more significant preservation of PBMC and rectal MNC Th17/Treg ratios, considered the strongest surrogate marker of progression to AIDS. We conclude that the vaccine platforms used in this study are insufficient to stimulate significant humoral immunity at the tested doses and schedule but sufficient to stimulate significant mucosal and systemic cell-mediated immunity, impacting the preservation of key Th17 CD4+ T cells in blood and rectal mucosa.

333 Management of Distal Radius Fractures During The COVID-19 Crisis

Introduction

Distal radius fractures are common. Treatment depends on a multitude of factors including the pattern / displacement of the fracture, patient age, pre-morbid function, and surgeon preference. We aim to investigate the effect of the pandemic on the management and short-term outcomes of patients with DRF’s.

Method

Retrospective review of all adult DRF’s two months before and after BOA released emergency standards on trauma management. The primary outcome measure was the proportion of patients managed non-operatively before and during COVID-19. Data extracted: demographics, comorbidities, cognitive baseline, treatment, and follow-up. Radiographs were reviewed for displacement [dorsal tilt (>10^o), ulnar variance (>3mm), intra-articular step (>2mm)].

Results

Pre-COVID (n = 29), COVID (n = 35). Characteristics were comparable in terms of median age (66 and 72 years, p = 0.41), %aged ≤65 (48% and 37%, p = 0.37), dominant side fracture (36% and 40%, p = 0.52), presence ≥ 2 co-morbidities (41% and 43%, p = 0.91). More patients were managed non-operatively during COVID (86% vs. 69%, p = 0.11), 2 of whom had unstable fracture pattern and developed malunion, compared to none in pre-COVID period.

Conclusions

Management of DRF’s remains a controversial topic, particularly in age <65 years. Long term follow up of patients with significant fracture displacement managed conservatively during COVID pandemic could help guide future practice.

Clinical characteristics and outcomes of pregnant women with COVID-19 and comparison with control patients: A systematic review and meta-analysis

In a large‐scale study, 128176 non‐pregnant patients (228 studies) and 10000 pregnant patients (121 studies) confirmed COVID‐19 cases included in this Meta‐Analysis. The mean (confidence interval [CI]) of age and gestational age of admission (GA) in pregnant women was 33 (28–37) years old and 36 (34–37) weeks, respectively. Pregnant women show the same manifestations of COVID‐19 as non‐pregnant adult patients. Fever (pregnant: 75.5%; non‐pregnant: 74%) and cough (pregnant: 48.5%; non‐pregnant: 53.5%) are the most common symptoms in both groups followed by myalgia (26.5%) and chill (25%) in pregnant and dysgeusia (27%) and fatigue (26.5%) in non‐pregnant patients. Pregnant women are less probable to show cough (odds ratio [OR] 0.7; 95% CI 0.67–0.75), fatigue (OR: 0.58; CI: 0.54–0.61), sore throat (OR: 0.66; CI: 0.61–0.7), headache (OR: 0.55; CI: 0.55–0.58) and diarrhea (OR: 0.46; CI: 0.4–0.51) than non‐pregnant adult patients. The most common imaging found in pregnant women is ground‐glass opacity (57%) and in non‐pregnant patients is consolidation (76%). Pregnant women have higher proportion of leukocytosis (27% vs. 14%), thrombocytopenia (18% vs. 12.5%) and have lower proportion of raised C‐reactive protein (52% vs. 81%) compared with non‐pregnant patients. Leucopenia and lymphopenia are almost the same in both groups. The most common comorbidity in pregnant patients is diabetes (18%) and in non‐pregnant patients is hypertension (21%). Case fatality rate (CFR) of non‐pregnant hospitalized patients is 6.4% (4.4–8.5), and mortality due to all‐cause for pregnant patients is 11.3% (9.6–13.3). Regarding the complications of pregnancy, postpartum hemorrhage (54.5% [7–94]), caesarean delivery (48% [42–54]), preterm labor (25% [4–74]) and preterm birth (21% [12–34]) are in turn the most prevalent complications. Comparing the pregnancy outcomes show that caesarean delivery (OR: 3; CI: 2–5), low birth weight (LBW) (OR: 9; CI: 2.4–30) and preterm birth (OR: 2.5; CI: 1.5–3.5) are more probable in pregnant woman with COVID‐19 than pregnant women without COVID‐19. The most prevalent neonatal complications are neonatal intensive care unit admission (43% [2–96]), fetal distress (30% [12–58]) and LBW (25% [16–37]). The rate of vertical transmission is 5.3% (1.3–16), and the rate of positive SARS‐CoV‐2 test for neonates born to mothers with COVID‐19 is 8% (4–16). Overall, pregnant patients present with the similar clinical characteristics of COVID‐19 when compared with the general population, but they may be more asymptomatic. Higher odds of caesarean delivery, LBW and preterm birth among pregnant patients with COVID‐19 suggest a possible association between COVID‐19 infection and pregnancy complications. Low risk of vertical transmission is present, and SARS‐CoV‐2 can be detected in all conception products, particularly placenta and breast milk. Interpretations of these results should be done cautiously due to the heterogeneity between studies; however, we believe our findings can guide the prenatal and postnatal considerations for COVID‐19 pregnant patients.

Comparative Evaluation of Prophylactic SIV Vaccination Modalities Administered to the Oral Cavity

Attempts to develop a protective human immunodeficiency virus (HIV) vaccine have had limited success, especially in terms of inducing protective antibodies capable of neutralizing different viral strains. As HIV transmission occurs mainly via mucosal surfaces, HIV replicates significantly in the gastrointestinal tract, and the oral route of vaccination is a very convenient one to implement worldwide, we explored three SIV vaccine modalities administered orally and composed of simian immunodeficiency virus (SIV) DNA priming with different boosting immunogens, with the goal of evaluating whether they could provide lasting humoral and cellular responses, including at mucosal surfaces that are sites of HIV entry. Twenty-four Cynomolgus macaques (CyM) were primed with replication-incompetent SIV DNA provirus and divided into three groups for the following booster vaccinations, all administered in the oral cavity: Group 1 with recombinant SIV gp140 and Escherichia coli heat-labile toxin adjuvant dmLT, Group 2 with recombinant SIV-Oral Poliovirus (SIV-OPV), and Group 3 with recombinant SIV-modified vaccinia ankara (SIV-MVA). Cell-mediated responses were measured using blood, lymph node, rectal and vaginal mononuclear cells. Significant levels of systemic and mucosal T-cell responses against Gag and Env were observed in all groups. Some SIV-specific plasma IgG, rectal and salivary IgA antibodies were generated, mainly in animals that received SIV DNA + SIV-MVA, but no vaginal IgA was detected. Susceptibility to infection after SIVmac251 challenge was similar in vaccinated and nonvaccinated animals, but acute infection viremia levels were lower in the group that received SIV DNA + SIV-MVA. Nonvaccinated CyM maintained central memory and total CD4+ T-cell levels in the normal range during the 5 months of postinfection follow-up as did the vaccinated animals, precluding evaluation of vaccine impact on disease progression. We conclude that the oral cavity vaccination tested in these regimens can stimulate cell-mediated immunity systemically and mucosally, but humoral response stimulation was limited with the doses and the vaccine platforms used.

Potential role of interferons in treating COVID-19 patients

The recently public health crises in the world is emerged by spreading the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also named COVID-19. The virus is originated in bats and transported to humans via undefined intermediate animals. This virus can produce from weak to severe respiratory diseases including acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), pneumonia and even death in patients. The COVID-19 disease is distributed by inhalation via contaminated droplets or contact with infected environment. The incubation time is from 2 to 14 day and the symptoms are typically fever, sore throat, cough, malaise, fatigue, breathlessness among others. It needs to be considered that many infected people are asymptomatic. Developing various immunological and virological methods to diagnose this disease is supported by several laboratories. Treatment is principally supportive; however, there are several agents that are using in treating of COVID-19 patients. Interferons (IFNs) have shown to be crucial in fighting with COVID-19 disease and can be a suitable candidate in treatment of these patients. Combination therapy can be more effective than monotherapy to cure this disease. Prevention necessitates to be performed by isolation of suspected people and home quarantine as well as taking care to infected people with mild or strict disease at hospitals. As the outbreak of SARS-CoV-2 has accelerated, developing effective therapy is an urgent requirement to battle the virus and prevent further pandemic. In this manuscript we reviewed available information about SARS-CoV-2 and probable therapies for COVID-19 patients.

A critical analysis of the COMPASS trial with respect to benefit-risk assessment using the numbers needed to treat: Applicability and relevance in Indian patients with stable cardiovascular disease

The recently published Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) trial evaluated the hypothesis that rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary prevention. In India, stable cardiovascular disease occurs in a much younger age group relative to the rest of the world. Our critical analysis of COMPASS trial showed that the younger age group appeared to derive greater benefit from the rivaroxaban+aspirin combination (relative to aspirin alone) as seen with number needed to treat metrics as compared to the older age group.

Measurement of the ν μ energy spectrum with IceCube-79: IceCube Collaboration

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The ν μ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of a multivariate classification process based on machine learning. The subsequent unfolding was performed using the software Truee. The resulting spectrum covers an E ν -range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows an excess of more than 1.9 σ in four adjacent bins for neutrino energies E ν ≥ 177.8 TeV . The obtained spectrum is fully compatible with previous measurements of the atmospheric neutrino flux and recent IceCube measurements of a flux of high-energy astrophysical neutrinos.

Plasmablastic lymphoma in HIV patients: Experience at a tertiary care hospital in eastern India

BACKGROUND

Plasmablastic lymphoma (PBL), a rare non-Hodgkin's lymphoma (NHL) variant specifically associated with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), expresses well-differentiated plasma cell markers like CD138, bright CD38, and MUM1; but not conventional B-cell markers. It occurs at unusual sites like oral cavity and orbit, and has poor survival rates.

AIMS

This study serves as a review of a clinical experience with six HIV patients with PBL and observes the spectrum of clinical presentations, histopathologies, and 1-year outcomes in PBL patients.

MATERIALS AND METHODS

This review of six PBL patients was conducted at a tertiary care hospital in eastern India using relevant radiological, histopathogical, and immunohistological studies.

RESULTS

Incidence of PBL among HIV patients was 0.58% (6/1,028). Mean CD4 count at presentation was 125.5 ± 71.1 cells/μL. Sites of involvement included pleura, lung parenchyma, suprarenal gland, pelvic cavity, and retroorbital space (one each). Immunohistopathology of biopsied sample in each patient revealed PBL (positive plasma cell markers MUM-1/IRF4, CD38, and CD138/syndecan; and negative of B-cell markers CD3, CD20, and CD30). Three (60%) were positive for Epstein Barr virus (EBV) immunoglobulin G (IgG). Five surviving patients received CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) regimen and attained partial remission (PR) after six cycles. Subsequently, three patients were started on EPOCH (etoposide, cyclophosphamide, doxorubicin, vincristine, prednisone) therapy; two attained near total regression after 6 months (four cycles). Overall, four patients remained alive with good quality of life at the end of 1 year of follow-up.

CONCLUSION

PBL in HIV occurs at unusual sites with varying aggressivity. This study is too small to comment on the long-term outcomes of PBL in HIV; however, coadministration of antiretroviral therapy (ART) with standard chemotherapy may improve survival.

Constraints on Ultrahigh-Energy Cosmic-Ray Sources from a Search for Neutrinos above 10 PeV with IceCube

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9}  GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5}  GeV to above 10^{11}  GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6}  GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5}  GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

Searches for Sterile Neutrinos with the IceCube Detector

The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{μ} or ν[over ¯]_{μ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3  eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.

Spectrometry of the Earth using Neutrino Oscillations

The unknown constituents of the interior of our home planet have provoked the human imagination and driven scientific exploration. We herein demonstrate that large neutrino detectors could be used in the near future to significantly improve our understanding of the Earth’s inner chemical composition. Neutrinos, which are naturally produced in the atmosphere, traverse the Earth and undergo oscillations that depend on the Earth’s electron density. The Earth’s chemical composition can be determined by combining observations from large neutrino detectors with seismic measurements of the Earth’s matter density. We present a method that will allow us to perform a measurement that can distinguish between composition models of the outer core. We show that the next-generation large-volume neutrino detectors can provide sufficient sensitivity to reject extreme cases of outer core composition. In the future, dedicated instruments could be capable of distinguishing between specific Earth composition models and thereby reshape our understanding of the inner Earth in previously unimagined ways.

Comparative Analysis of Tat-Dependent and Tat-Deficient Natural Lentiviruses

The emergence of human immunodeficiency virus (HIV) causing acquired immunodeficiency syndrome (AIDS) in infected humans has resulted in a global pandemic that has killed millions. HIV-1 and HIV-2 belong to the lentivirus genus of the Retroviridae family. This genus also includes viruses that infect other vertebrate animals, among them caprine arthritis-encephalitis virus (CAEV) and Maedi-Visna virus (MVV), the prototypes of a heterogeneous group of viruses known as small ruminant lentiviruses (SRLVs), affecting both goat and sheep worldwide. Despite their long host-SRLV natural history, SRLVs were never found to be responsible for immunodeficiency in contrast to primate lentiviruses. SRLVs only replicate productively in monocytes/macrophages in infected animals but not in CD4+ T cells. The focus of this review is to examine and compare the biological and pathological properties of SRLVs as prototypic Tat-independent lentiviruses with HIV-1 as prototypic Tat-dependent lentiviruses. Results from this analysis will help to improve the understanding of why and how these two prototypic lentiviruses evolved in opposite directions in term of virulence and pathogenicity. Results may also help develop new strategies based on the attenuation of SRLVs to control the highly pathogenic HIV-1 in humans.

Evidence for Astrophysical Muon Neutrinos from the Northern Sky with IceCube

Results from the IceCube Neutrino Observatory have recently provided compelling evidence for the existence of a high energy astrophysical neutrino flux utilizing a dominantly Southern Hemisphere data set consisting primarily of ν(e) and ν(τ) charged-current and neutral-current (cascade) neutrino interactions. In the analysis presented here, a data sample of approximately 35,000 muon neutrinos from the Northern sky is extracted from data taken during 659.5 days of live time recorded between May 2010 and May 2012. While this sample is composed primarily of neutrinos produced by cosmic ray interactions in Earth's atmosphere, the highest energy events are inconsistent with a hypothesis of solely terrestrial origin at 3.7σ significance. These neutrinos can, however, be explained by an astrophysical flux per neutrino flavor at a level of Φ(E(ν))=9.9(-3.4)(+3.9)×10(-19)  GeV(-1) cm(-2) sr(-1) s(-1)(E(ν)/100  TeV(-2), consistent with IceCube's Southern-Hemisphere-dominated result. Additionally, a fit for an astrophysical flux with an arbitrary spectral index is performed. We find a spectral index of 2.2(-0.2)(+0.2), which is also in good agreement with the Southern Hemisphere result.

Management of infected nonunion of the long bones by a multidisciplinary team

Infected nonunion of a long bone continues to present difficulties in management. In addition to treating the infection, it is necessary to establish bony stability, encourage fracture union and reconstruct the soft-tissue envelope. We present a series of 67 infected nonunions of a long bone in 66 patients treated in a multidisciplinary unit. The operative treatment of patients suitable for limb salvage was performed as a single procedure. Antibiotic regimes were determined by the results of microbiological culture. At a mean follow-up of 52 months (22 to 97), 59 patients (88%) had an infection-free united fracture in a functioning limb. Seven others required amputation (three as primary treatment, three after late failure of limb salvage and one for recalcitrant pain after union). The initial operation achieved union in 54 (84%) of the salvaged limbs at a mean of nine months (three to 26), with recurrence of infection in 9%. Further surgery in those limbs that remained ununited increased the union rate to 62 (97%) of the 64 limbs treated by limb salvage at final follow-up. The use of internal fixation was associated with a higher risk of recurrent infection than external fixation.

Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube

A diffuse flux of astrophysical neutrinos above 100 TeV has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to 35 TeV and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for showerlike events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the (fe:fμ:fτ)⊕≈(1:1:1)⊕ flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on nonstandard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally tracklike composition of (0:1:0)⊕ is excluded at 3.3σ, and a purely showerlike composition of (1:0:0)⊕ is excluded at 2.3σ.

Development of a general analysis and unfolding scheme and its application to measure the energy spectrum of atmospheric neutrinos with IceCube: IceCube Collaboration

We present the development and application of a generic analysis scheme for the measurement of neutrino spectra with the IceCube detector. This scheme is based on regularized unfolding, preceded by an event selection which uses a Minimum Redundancy Maximum Relevance algorithm to select the relevant variables and a random forest for the classification of events. The analysis has been developed using IceCube data from the 59-string configuration of the detector. 27,771 neutrino candidates were detected in 346 days of livetime. A rejection of 99.9999 % of the atmospheric muon background is achieved. The energy spectrum of the atmospheric neutrino flux is obtained using the TRUEE unfolding program. The unfolded spectrum of atmospheric muon neutrinos covers an energy range from 100 GeV to 1 PeV. Compared to the previous measurement using the detector in the 40-string configuration, the analysis presented here, extends the upper end of the atmospheric neutrino spectrum by more than a factor of two, reaching an energy region that has not been previously accessed by spectral measurements.

Observation of high-energy astrophysical neutrinos in three years of IceCube data

A search for high-energy neutrinos interacting within the IceCube detector between 2010 and 2012 provided the first evidence for a high-energy neutrino flux of extraterrestrial origin. Results from an analysis using the same methods with a third year (2012-2013) of data from the complete IceCube detector are consistent with the previously reported astrophysical flux in the 100 TeV-PeV range at the level of 10(-8)  GeV cm-2 s-1 sr-1 per flavor and reject a purely atmospheric explanation for the combined three-year data at 5.7σ. The data are consistent with expectations for equal fluxes of all three neutrino flavors and with isotropic arrival directions, suggesting either numerous or spatially extended sources. The three-year data set, with a live time of 988 days, contains a total of 37 neutrino candidate events with deposited energies ranging from 30 to 2000 TeV. The 2000-TeV event is the highest-energy neutrino interaction ever observed.

Patient-reported outcomes following treatment of tibial non-union with circular frames

The management of tibial non-union is challenging with protracted, often arduous, treatments. The purpose of this study was to assess patient-reported outcomes following treatment of tibial non-union in circular external fixators. Twenty-one patients with tibial non-unions who successfully completed treatment at a mean of 10.1 months (range 6–20) in a circular external fixator were sent questionnaires utilising the Enneking scoring system and Euroqol EQ-5D. There were 14 responses. The mean Enneking score was 58.0 % (34.3–77.1). Two patients were enthusiastic about their treatment, while three accepted but would not repeat the treatment. The Euroqol questionnaire found that 8 patients had difficulty with mobility, 10 had difficulty with usual activities and 12 had moderate pain. There was no statistically significant difference in the EQ VAS score of overall health state for treated patients compared with predicted scores for an age- and sex-matched UK population (77.7 vs 83.1, p = 0.07).

Evidence for high-energy extraterrestrial neutrinos at the IceCube detector

We report on results of an all-sky search for high-energy neutrino events interacting within the IceCube neutrino detector conducted between May 2010 and May 2012. The search follows up on the previous detection of two PeV neutrino events, with improved sensitivity and extended energy coverage down to about 30 TeV. Twenty-six additional events were observed, substantially more than expected from atmospheric backgrounds. Combined, both searches reject a purely atmospheric origin for the 28 events at the 4σ level. These 28 events, which include the highest energy neutrinos ever observed, have flavors, directions, and energies inconsistent with those expected from the atmospheric muon and neutrino backgrounds. These properties are, however, consistent with generic predictions for an additional component of extraterrestrial origin.

Measurement of atmospheric neutrino oscillations with IceCube

We present the first statistically significant detection of neutrino oscillations in the high-energy regime (>20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (~20 GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20-100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5σ significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters |Δm(32)(2)|=(2.3(-0.5)(+0.6))×10(-3) eV(2) and sin(2)(2θ(23))>0.93, and maximum mixing is favored.

First observation of PeV-energy neutrinos with IceCube

We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04±0.16 and 1.14±0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current ν(e,μ,τ) (ν(e,μ,τ)) or charged-current ν(e) (ν(e)) interactions within the IceCube detector. The events were discovered in a search for ultrahigh energy neutrinos using data corresponding to 615.9 days effective live time. The expected number of atmospheric background is 0.082±0.004(stat)(-0.057)(+0.041)(syst). The probability of observing two or more candidate events under the atmospheric background-only hypothesis is 2.9×10(-3) (2.8σ) taking into account the uncertainty on the expected number of background events. These two events could be a first indication of an astrophysical neutrino flux; the moderate significance, however, does not permit a definitive conclusion at this time.

Measurement of the atmospheric νe flux in IceCube

We report the first measurement of the atmospheric electron neutrino flux in the energy range between approximately 80 GeV and 6 TeV, using data recorded during the first year of operation of IceCube's DeepCore low-energy extension. Techniques to identify neutrinos interacting within the DeepCore volume and veto muons originating outside the detector are demonstrated. A sample of 1029 events is observed in 281 days of data, of which 496±66(stat)±88(syst) are estimated to be cascade events, including both electron neutrino and neutral current events. The rest of the sample includes residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muon neutrinos. The flux of the atmospheric electron neutrinos is consistent with models of atmospheric neutrinos in this energy range. This constitutes the first observation of electron neutrinos and neutral current interactions in a very large volume neutrino telescope optimized for the TeV energy range.

Search for dark matter annihilations in the sun with the 79-string IceCube detector

We have performed a search for muon neutrinos from dark matter annihilation in the center of the Sun with the 79-string configuration of the IceCube neutrino telescope. For the first time, the DeepCore subarray is included in the analysis, lowering the energy threshold and extending the search to the austral summer. The 317 days of data collected between June 2010 and May 2011 are consistent with the expected background from atmospheric muons and neutrinos. Upper limits are set on the dark matter annihilation rate, with conversions to limits on spin-dependent and spin-independent scattering cross sections of weakly interacting massive particles (WIMPs) on protons, for WIMP masses in the range 20-5000  GeV/c2. These are the most stringent spin-dependent WIMP-proton cross section limits to date above 35  GeV/c2 for most WIMP models.

Outcome of arthrodesis of the hindfoot as a salvage procedure for complex ankle pathology using the Ilizarov technique

Achieving arthrodesis of the ankle can be difficult in the presence of infection, deformity, poor soft tissues and bone loss. We present a series of 48 patients with complex ankle pathology, treated with the Ilizarov technique. Infection was present in 30 patients and 30 had significant deformity before surgery. Outcome was assessed clinically and with patient-reported outcome measures (Modified American Orthopaedic Foot and Ankle Society (MAOFAS) scale and the Short-Form (SF-36)).

Arthrodesis was achieved in 40 patients with the Ilizarov technique alone and in six further patients with additional surgery. Infection was eradicated in all patients at a mean follow-up of 46.6 months (13 to 162). Successful arthrodesis was less likely in those with comorbidities and in tibiocalcaneal fusion compared with tibiotalar fusion.

These patients had poor general health scores compared with the normal population before surgery. The mean MAOFAS score improved significantly from 24.3 (0 to 90) pre-operatively to 56.2 (30 to 90) post-operatively, but there was only a modest improvement in general health; the mean SF-36 improved from 44.8 (19 to 66) to 50.1 (21 to 76). There was a major benefit in terms of pain relief.

Arthrodesis using the Ilizarov technique is an effective treatment for complex ankle pathology, with good clinical outcomes and eradication of infection. However, even after successful arthrodesis general health scores remain limited.

Cite this article: Bone Joint J 2013;95-B:371–7.

Chemoresistant colorectal cancer cells and cancer stem cells mediate growth and survival of bystander cells

BACKGROUND

Recent studies suggest that cancer stem cells (CSCs) mediate chemoresistance, but interestingly, only a small percentage of cells in a resistant tumour are CSCs; this suggests that non-CSCs survive by other means. We hypothesised that chemoresistant colorectal cancer (CRC) cells generate soluble factors that enhance survival of chemonaive tumour cells.

METHODS

Chemoresistant CRC cells were generated by serial passage in oxaliplatin (Ox cells). Conditioned media (CM) was collected from parental and oxaliplatin-resistant (OxR) cells. CRC cells were treated with CM and growth and survival were assessed. Tumour growth rates were determined in nude mice after cells were treated with CM. Mass spectrometry (MS) identified proteins in CM. Reverse phase protein microarray assays determined signalling effects of CM in parental cells.

RESULTS

Oxaliplatin-resistant CM increased survival of chemo-naive cells. CSC CM also increased growth of parental cells. Parental and OxR mixed tumours grew larger than tumours composed of parental or OxR cells alone. Mass spectrometry detected unique survival-promoting factors in OxR CM compared with parental CM. Cells treated with OxR CM demonstrated early phosphorylation of EGFR and MEK1, with later upregulation of total Akt .We identified progranulin as a potential mediator of chemoresistance.

CONCLUSION

Chemoresistant tumour cells and CSCs may promote resistance through soluble factors that mediate survival in otherwise chemosensitive tumour cells.

Limits on neutrino emission from gamma-ray bursts with the 40 string IceCube detector

IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18)  eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence.

Chronic exposure of colorectal cancer cells to bevacizumab promotes compensatory pathways that mediate tumour cell migration

BACKGROUND

Bevacizumab (Bev), a monoclonal antibody to vascular endothelial growth factor (VEGF), is used in combination with chemotherapy for the treatment of metastatic colorectal cancer (CRC). The effects of Bev on angiogenesis have been well described, but the direct effect of Bev on tumour cells is unknown. This study was carried out to determine the molecular and phenotypic changes in CRC cells after chronic Bev exposure in vitro.

METHODS

Human CRC cell lines were chronically exposed (3 months) to Bev in vitro to develop Bev-adapted (Bev-A) cell lines. Vascular endothelial growth factor family members were determined by reverse transcription-polymerase chain reaction and western blotting. Migration and invasion was determined using standard in vitro assays. Intravenous injection of tumour cells was carried out to evaluate metastatic potential in mice.

RESULTS

Bevacizumab-adapted cells were found to be more migratory and invasive than control cells (P<0.001). Bevacizumab-adapted cells showed higher levels of VEGF-A, -B, -C, placental growth factor (PlGF), VEGF receptor-1 (VEGFR-1) and phosphorylation of VEGFR-1. Furthermore, treatment with SU5416, a VEGFR protein tyrosine kinase inhibitor, led to significantly decreased cell migration in vitro (P<0.001). Bevacizumab-adapted cells were more metastatic in vivo (P<0.05).

CONCLUSION

Chronic exposure of CRC cells to Bev (1) increased expression of VEGF-A, -B, -C, PlGF, VEGFR-1 and VEGFR-1 phosphorylation, (2) increased tumour cell migration and invasion, and (3) metastatic potential in vivo. Our study shows the functional significance of autocrine VEGF signalling in CRC cells.

Factors influencing the choice of drug therapy in primary and secondary health care

A prescribing decision model incorporating drug characteristics, professional opinions and past experience was used to predict the choices made by prescribers when selecting a non-steroidal anti-inflammatory drug (NSAID) for inclusion in a formulary. Thirty general practitioners (GPs) and 14 hospital doctors (HDs), most practising within the South East Thames regional health authority, were asked to select either ibuprofen, diclofenac or indomethacin, based on the needs of a described population, and then to answer a questionnaire.

Looking at the relative importance of factors influencing the choice of treatment, there was generally a high degree of agreement between HDs and GPs. However, the majority of HDs ranked efficacy as the most important drug characteristic whereas GPs were generally more concerned with side effects. Fundholding GPs ranked cost more highly than did their non-fundholding counterparts, and GPs working in single handed practices were more influenced by specialists and company representatives than were GPs working in groups. The decision model correctly predicted the drug choice of all the HDs and of 76 per cent of the GPs. These values were considerably better than the 33 per cent that would be predicted based on chance alone.

Although various limitations of this type of study are noted, it is hoped that the model could be developed as a valuable tool to assist in understanding complex prescribing issues.

Evaluation of glycolytic activity and HIF-1α expression in chemoresistant colorectal cancer cells

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Background: Overcoming drug resistance in colorectal cancer (CRC) involves understanding the mechanisms by which cancer cells adapt to the genotoxic stress. We established a model of oxaliplatin resistant cells derived from HCT116/HT29 (HCT116 OxR/HT29 OxR). How these resistant clones reprogram their energy metabolism to gain a survival advantage remains unknown. We hypothesized that chemoresistant CRC cells exhibit altered cellular metabolism to survive following chronic genotoxic stress.

Methods: The expression levels of glycolytic enzymes were detected by Western Blotting. Glucose and lactate concentrations were measured in the culturing media (CM). Intracellular ATP/ADP levels, oxygen consumption rate (OCR) and mitochondria ATP production were measured. In vivo xenograft study was used to compare the growth rate and angiogenesis of parental and oxaliplatin-resistant cells.

Results: Both HT29-OxR and HCT116-OxR cells compared to parental cells exhibit increased aerobic glycolysis. Consistently, Glut1, Hexokinase 2 and LDHA glycolytic enzymes are upregulated. The OxR cells are defective in mitochondria complex I/II substrate and ATP production despite increased OCR. Importantly, the OXR cells maintain higher intracellular ATP and ATP/ADP ratio, increased HIF1a and VEGF levels in the CM. In tumor xenograft model, HT29 OxR cells grow significant slower than parental HT29 cells. Interestingly, when OxR cells were mixed with parental HT29 cells (50:50 and 90:10), tumor growth and microvessel counts were significantly accelerated.

Conclusions: OxR cells demonstrate: 1) high aerobic glycolytic activity; 2) defective mitochondria functions; 3) increased ATP production; 4) increased HIF1a and angiogenesis. Likely, this metabolic switch contributes to the resistant phenotype. Metabolism intervention such as targeting HIF1a may provide a novel strategy to overcome drug-resistance in CRC.

No significant financial relationships to disclose.