Specific Residues in the C-Terminal Domain of the Human Metapneumovirus Phosphoprotein Are Indispensable for Formation of Viral Replication Centers and Regulation of the Function of the Viral Polymerase Complex

Human metapneumovirus (HMPV) is a negative-strand RNA virus that frequently causes respiratory tract infections in infants, the elderly, and the immunocompromised. A hallmark of HMPV infection is the formation of membraneless, liquid-like replication and transcription centers in the cytosol termed inclusion bodies (IBs). The HMPV phosphoprotein (P) and nucleoprotein (N) are the minimal viral proteins necessary to form IB-like structures, and both proteins are required for the viral polymerase to synthesize RNA during infection. HMPV P is a homotetramer with regions of intrinsic disorder and has several known and predicted phosphorylation sites of unknown function. In this study, we found that the P C-terminal intrinsically disordered domain (CTD) must be present to facilitate IB formation with HMPV N, while either the N-terminal intrinsically disordered domain or the central oligomerization domain was dispensable. Alanine substitution at a single tyrosine residue within the CTD abrogated IB formation and reduced coimmunoprecipitation with HMPV N. Mutations to C-terminal phosphorylation sites revealed a potential role for phosphorylation in regulating RNA synthesis and P binding partners within IBs. Phosphorylation mutations which reduced RNA synthesis in a reporter assay produced comparable results in a recombinant viral rescue system, measured as an inability to produce infectious viral particles with genomes containing these single P mutations. This work highlights the critical role HMPV P plays in facilitating a key step of the viral life cycle and reveals the potential role for phosphorylation in regulating the function of this significant viral protein. IMPORTANCE Human metapneumovirus (HMPV) infects global populations, with severe respiratory tract infections occurring in infants, the elderly, and the immunocompromised. There are currently no FDA-approved therapeutics available to prevent or treat HMPV infection. Therefore, understanding how HMPV replicates is vital for the identification of novel targets for therapeutic development. During HMPV infection, viral RNA synthesis proteins localize to membraneless structures called inclusion bodies (IBs), which are sites of genome replication and transcription. The HMPV phosphoprotein (P) is necessary for IBs to form and for the virus to synthesize RNA, but it is not known how this protein contributes to IB formation or if it is capable of regulating viral replication. We show that the C-terminal domain of P is the location of a molecular interaction driving IB formation and contains potential phosphorylation sites where amino acid charge regulates the function of the viral polymerase complex.

Human Metapneumovirus Phosphoprotein Independently Drives Phase Separation and Recruits Nucleoprotein to Liquid-Like Bodies

Human metapneumovirus (HMPV) inclusion bodies (IBs) are dynamic structures required for efficient viral replication and transcription. The minimum components needed to form IB-like structures in cells are the nucleoprotein (N) and the tetrameric phosphoprotein (P). HMPV P binds to the following two versions of the N protein in infected cells: N-terminal P residues interact with monomeric N (N0) to maintain a pool of protein to encapsidate new RNA and C-terminal P residues interact with oligomeric, RNA-bound N (N-RNA). Recent work on other negative-strand viruses has suggested that IBs are, at least in part, liquid-like phase-separated membraneless organelles. Here, HMPV IBs in infected or transfected cells were shown to possess liquid organelle properties, such as fusion and fission. Recombinant versions of HMPV N and P proteins were purified to analyze the interactions required to drive phase separation in vitro. Purified HMPV P was shown to form liquid droplets in isolation. This observation is distinct from other viral systems that also form IBs. Partial removal of nucleic acid from purified P altered phase-separation dynamics, suggesting that nucleic acid interactions play a role in IB formation. HMPV P also recruits monomeric N (N0-P) and N-RNA to droplets in vitro. These findings suggest that HMPV P may also act as a scaffold protein to mediate multivalent interactions with monomeric and oligomeric N, as well as RNA, to promote phase separation of IBs. Together, these findings highlight an additional layer of regulation in HMPV replication by the viral P and N proteins. IMPORTANCE Human metapneumovirus (HMPV) is a leading cause of respiratory disease among children, immunocompromised individuals, and the elderly. Currently, no vaccines or antivirals are available for the treatment of HMPV infections. Cytoplasmic inclusion bodies (IBs), where HMPV replication and transcription occur, represent a promising target for the development of novel antivirals. The HMPV nucleoprotein (N) and phosphoprotein (P) are the minimal components needed for IB formation in eukaryotic cells. However, interactions that regulate the formation of these dynamic structures are poorly understood. Here, we showed that HMPV IBs possess the properties of liquid organelles and that purified HMPV P phase separates independently in vitro. Our work suggests that HMPV P phase-separation dynamics are altered by nucleic acid. We provide strong evidence that, unlike results reported from other viral systems, HMPV P alone can serve as a scaffold for multivalent interactions with monomeric (N0) and oligomeric (N-RNA) HMPV N for IB formation.

Demonstration of Hollow Fiber Membrane-Based Enclosed Space Air Remediation for Capture of an Aerosolized Synthetic SARS-CoV-2 Mimic and Pseudovirus Particles

Reduction of airborne viral particles in enclosed spaces is critical in controlling pandemics. Three different hollow fiber membrane (HFM) modules were investigated for viral aerosol separation in enclosed spaces. Pore structures were characterized by scanning electron microscopy, and air transport properties were measured. Particle removal efficiency was characterized using aerosols generated by a collision atomizer from a defined mixture of synthetic nanoparticles including SARS-CoV-2 mimics (protein-coated 100 nm polystyrene). HFM1 (polyvinylidene fluoride, ~50-1300 nm pores) demonstrated 96.5-100% efficiency for aerosols in the size range of 0.3-3 μm at a flow rate of 18.6 ± 0.3 SLPM (~1650 LMH), whereas HFM2 (polypropylene, ~40 nm pores) and HFM3 (hydrophilized polyether sulfone, ~140-750 nm pores) demonstrated 99.65-100% and 98.8-100% efficiency at flow rates of 19.7 ± 0.3 SLPM (~820 LMH) and 19.4 ± 0.2 SLPM (~4455 LMH), respectively. Additionally, lasting filtration with minimal fouling was demonstrated using ambient aerosols over 2 days. Finally, each module was evaluated with pseudovirus (vesicular stomatitis virus) aerosol, demonstrating 99.3% (HFM1), >99.8% (HFM2), and >99.8% (HFM3) reduction in active pseudovirus titer as a direct measure of viral particle removal. These results quantified the aerosol separation efficiency of HFMs and highlight the need for further development of this technology to aid the fight against airborne viruses and particulate matter concerning human health.

Effect of clinical isolate or cleavage site mutations in the SARS-CoV-2 spike protein on protein stability, cleavage, and cell-cell fusion

The trimeric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S) is the sole viral protein responsible for both viral binding to a host cell and the membrane fusion event needed for cell entry. In addition to facilitating fusion needed for viral entry, S can also drive cell-cell fusion, a pathogenic effect observed in the lungs of SARS-CoV-2-infected patients. While several studies have investigated S requirements involved in viral particle entry, examination of S stability and factors involved in S cell-cell fusion remain limited. A furin cleavage site at the border between the S1 and S2 subunits (S1/S2) has been identified, along with putative cathepsin L and transmembrane serine protease 2 cleavage sites within S2. We demonstrate that S must be processed at the S1/S2 border in order to mediate cell-cell fusion and that mutations at potential cleavage sites within the S2 subunit alter S processing at the S1/S2 border, thus preventing cell-cell fusion. We also identify residues within the internal fusion peptide and the cytoplasmic tail that modulate S-mediated cell-cell fusion. In addition, we examined S stability and protein cleavage kinetics in a variety of mammalian cell lines, including a bat cell line related to the likely reservoir species for SARS-CoV-2, and provide evidence that proteolytic processing alters the stability of the S trimer. This work therefore offers insight into S stability, proteolytic processing, and factors that mediate S cell-cell fusion, all of which help give a more comprehensive understanding of this high-profile therapeutic target.

Effect of mutations in the SARS-CoV-2 spike protein on protein stability, cleavage, and cell-cell fusion function

The SARS-CoV-2 spike protein (S) is the sole viral protein responsible for both viral binding to a host cell and the membrane fusion event needed for cell entry. In addition to facilitating fusion needed for viral entry, S can also drive cell-cell fusion, a pathogenic effect observed in the lungs of SARS-CoV-2 infected patients. While several studies have investigated S requirements involved in viral particle entry, examination of S stability and factors involved in S cell-cell fusion remain limited. We demonstrate that S must be processed at the S1/S2 border in order to mediate cell-cell fusion, and that mutations at potential cleavage sites within the S2 subunit alter S processing at the S1/S2 border, thus preventing cell-cell fusion. We also identify residues within the internal fusion peptide and the cytoplasmic tail that modulate S cell-cell fusion. Additionally, we examine S stability and protein cleavage kinetics in a variety of mammalian cell lines, including a bat cell line related to the likely reservoir species for SARS-CoV-2, and provide evidence that proteolytic processing alters the stability of the S trimer. This work therefore offers insight into S stability, proteolytic processing, and factors that mediate S cell-cell fusion, all of which help give a more comprehensive understanding of this highly sought-after therapeutic target.

Recommendations on managing lenvatinib and everolimus in patients with advanced or metastatic renal cell carcinoma

INTRODUCTION

There are several second-line treatment options for patients with renal cell carcinoma after first-line failure of a tyrosine kinase inhibitor, especially with the recent approvals of cabozantinib, nivolumab, and the lenvatinib plus everolimus combination. A lack of reliable biomarkers and an overall lack of prospective head-to-head comparisons make it a challenge to choose a second-line treatment in the clinic. Areas covered: In this review/meta-opinion, we describe the safety profile of the lenvatinib plus everolimus combination in renal cell carcinoma. The combination of lenvatinib plus everolimus has achieved the highest rates of objective responses and the longest progression free and overall survival in cross-comparison trials. At the same time, the safety profile of this combination, including the rate of total and severe adverse events, the percentage of dose reductions required, and the rate of treatment discontinuation, was less favorable compared with available monotherapy options, suggesting that better management could help to maximize the activity of this combination while protecting patients from undue harm. Expert opinion: Herein, we aim to postulate multidisciplinary recommendations on the advice to offer to patients and caregivers before starting treatment and how to manage the combination from the perspective of daily clinical practice.

Oncologic doses of zoledronic acid induce site specific suppression of bone modelling in rice rats

OBJECTIVES

To examine the effect of zoledronic acid (ZOL) on cortical bone modelling and healing of extraction sockets in the jaw bones of a rodent model. We hypothesized ZOL suppresses both the bone formation in the modelling mode in the jaw bones and alters the extraction site healing.

MATERIAL & METHODS

Rice rats were administered saline solution and two dose regimens of ZOL: 0.1 mg/kg, twice a week, for 4 weeks (n=17, saline=8 & ZOL=9) and a higher dose of 0.4 mg/kg, weekly, for 9 weeks (n=30, saline=15 & ZOL=15). Two pairs of fluorochrome bone labels were administered. Extraction of maxillary teeth was performed in maxilla. Mineral apposition rate, mineralizing surface and bone formation rate (BFR) were quantified on periodontal (PDL), alveolar and basal bone surfaces, and in the trabecular bone of proximal tibia. Bone volume (BV) was evaluated at extraction sockets. Multivariate Gaussian models were used to account for repeated measurements, and analyzes were conducted in SAS V9.3.

RESULTS

ZOL suppressed bone modelling (BFR/BS) at the PDL surfaces in the mandible (P<.05), but its effect was not significant at the periosteal surfaces of both jaws. BV for the healing sockets of ZOL treated animals was not significantly different (P=.07) compared to the saline group. ZOL suppressive effect was higher in the tibia compared to the jaws.

CONCLUSION

ZOL severely suppresses coupled remodelling in the tibia, and the suppression of bone formation in the modelling mode in the jaws demonstrates the site specific effects of ZOL in rice rats.

The differential production cross section of the [Formula: see text](1020) meson in [Formula: see text] = 7 TeV [Formula: see text] collisions measured with the ATLAS detector

A measurement is presented of the [Formula: see text] production cross section at [Formula: see text] = 7 TeV using [Formula: see text] collision data corresponding to an integrated luminosity of 383 [Formula: see text], collected with the ATLAS experiment at the LHC. Selection of [Formula: see text](1020) mesons is based on the identification of charged kaons by their energy loss in the pixel detector. The differential cross section is measured as a function of the transverse momentum, [Formula: see text], and rapidity, [Formula: see text], of the [Formula: see text](1020) meson in the fiducial region 500 [Formula: see text] 1200 MeV, [Formula: see text] 0.8, kaon [Formula: see text] 230 MeV and kaon momentum [Formula: see text] 800 MeV. The integrated [Formula: see text]-meson production cross section in this fiducial range is measured to be [Formula: see text] = 570 [Formula: see text] 8 (stat) [Formula: see text] 66 (syst) [Formula: see text] 20 (lumi) [Formula: see text].

Australian per caput dose from diagnostic imaging and nuclear medicine

The largest man-made contributor to the ionising radiation dose to the Australian population is from diagnostic imaging and nuclear medicine. The last estimation of this dose was made in 2004 (1.3 mSv), this paper describes a recent re-evaluation of this dose to reflect the changes in imaging trends and technology. The estimation was calculated by summing the dose from five modalities, computed tomography (CT), general radiography/fluoroscopy, interventional procedures, mammography and nuclear medicine. Estimates were made using Australian frequency data and dose data from a range of Australian and international sources of average effective dose values. The ionising radiation dose to the Australian population in 2010 from diagnostic imaging and nuclear medicine is estimated to be 1.7 mSv (1.11 mSv CT, 0.30 mSv general radiography/fluoroscopy, 0.17 mSv interventional procedures, 0.03 mSv mammography and 0.10 mSv nuclear medicine). This exceeds the estimate of 1.5 mSv per person from natural background and cosmic radiation.

Improved luminosity determination in pp collisions at [Formula: see text] using the ATLAS detector at the LHC

The luminosity calibration for the ATLAS detector at the LHC during pp collisions at [Formula: see text] in 2010 and 2011 is presented. Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the pp collisions at [Formula: see text]. A luminosity uncertainty of [Formula: see text] is obtained for the 47 pb-1 of data delivered to ATLAS in 2010, and an uncertainty of [Formula: see text] is obtained for the 5.5 fb-1 delivered in 2011.

Measurement of the inclusive jet cross-section in pp collisions at [Formula: see text] and comparison to the inclusive jet cross-section at [Formula: see text] using the ATLAS detector

The inclusive jet cross-section has been measured in proton-proton collisions at [Formula: see text] in a dataset corresponding to an integrated luminosity of [Formula: see text] collected with the ATLAS detector at the Large Hadron Collider in 2011. Jets are identified using the anti-kt algorithm with two radius parameters of 0.4 and 0.6. The inclusive jet double-differential cross-section is presented as a function of the jet transverse momentum pT and jet rapidity y, covering a range of 20≤pT<430 GeV and |y|<4.4. The ratio of the cross-section to the inclusive jet cross-section measurement at [Formula: see text], published by the ATLAS Collaboration, is calculated as a function of both transverse momentum and the dimensionless quantity [Formula: see text], in bins of jet rapidity. The systematic uncertainties on the ratios are significantly reduced due to the cancellation of correlated uncertainties in the two measurements. Results are compared to the prediction from next-to-leading order perturbative QCD calculations corrected for non-perturbative effects, and next-to-leading order Monte Carlo simulation. Furthermore, the ATLAS jet cross-section measurements at [Formula: see text] and [Formula: see text] are analysed within a framework of next-to-leading order perturbative QCD calculations to determine parton distribution functions of the proton, taking into account the correlations between the measurements.

Jet energy resolution in proton-proton collisions at [Formula: see text] recorded in 2010 with the ATLAS detector

The measurement of the jet energy resolution is presented using data recorded with the ATLAS detector in proton-proton collisions at [Formula: see text]. The sample corresponds to an integrated luminosity of 35 pb-1. Jets are reconstructed from energy deposits measured by the calorimeters and calibrated using different jet calibration schemes. The jet energy resolution is measured with two different in situ methods which are found to be in agreement within uncertainties. The total uncertainties on these measurements range from 20 % to 10 % for jets within |y|<2.8 and with transverse momenta increasing from 30 GeV to 500 GeV. Overall, the Monte Carlo simulation of the jet energy resolution agrees with the data within 10 %.

Measurement of Z boson production in Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV with the ATLAS detector

The ATLAS experiment has observed 1995 Z boson candidates in data corresponding to 0.15  nb(-1) of integrated luminosity obtained in the 2011 LHC Pb+Pb run at sqrt[s(NN)]=2.76  TeV. The Z bosons are reconstructed via dielectron and dimuon decay channels, with a background contamination of less than 3%. Results from the two channels are consistent and are combined. Within the statistical and systematic uncertainties, the per-event Z boson yield is proportional to the number of binary collisions estimated by the Glauber model. The elliptic anisotropy of the azimuthal distribution of the Z boson with respect to the event plane is found to be consistent with zero.

Search for dark matter candidates and large extra dimensions in events with a photon and missing transverse momentum in pp collision data at sqrt[s]=7 TeV with the ATLAS detector

Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum in proton-proton collisions at sqrt[s] = 7 TeV are reported. Data collected by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 4.6 fb(-1) are used. Good agreement is observed between the data and the standard model predictions. The results are translated into exclusion limits on models with large extra spatial dimensions and on pair production of weakly interacting dark matter candidates.

Search for magnetic monopoles in sqrt[s]=7 TeV pp collisions with the ATLAS detector

This Letter presents a search for magnetic monopoles with the ATLAS detector at the CERN Large Hadron Collider using an integrated luminosity of 2.0  fb(-1) of pp collisions recorded at a center-of-mass energy of sqrt[s]=7  TeV. No event is found in the signal region, leading to an upper limit on the production cross section at 95% confidence level of 1.6/ϵ  fb for Dirac magnetic monopoles with the minimum unit magnetic charge and with mass between 200 GeV and 1500 GeV, where ϵ is the monopole reconstruction efficiency. The efficiency ϵ is high and uniform in the fiducial region given by pseudorapidity |η|<1.37 and transverse kinetic energy 600-700<E(kin)sinθ<1400  GeV. The minimum value of 700 GeV is for monopoles of mass 200 GeV, whereas the minimum value of 600 GeV is applicable for higher mass monopoles. Therefore, the upper limit on the production cross section at 95% confidence level is 2 fb in this fiducial region. Assuming the kinematic distributions from Drell-Yan pair production of spin-1/2 Dirac magnetic monopoles, the efficiency is in the range 1%-10%, leading to an upper limit on the cross section at 95% confidence level that varies from 145 fb to 16 fb for monopoles with mass between 200 GeV and 1200 GeV. This limit is weaker than the fiducial limit because most of these monopoles lie outside the fiducial region.

Search for direct top squark pair production in final states with one isolated lepton, jets, and missing transverse momentum in sqrt[s] = 7 TeV pp collisions using 4.7 fb(-10 of ATLAS data

A search is presented for direct top squark pair production in final states with one isolated electron or muon, jets, and missing transverse momentum in proton-proton collisions at sqrt[s] = 7 TeV. The measurement is based on 4.7 fb(-1) of data collected with the ATLAS detector at the LHC. Each top squark is assumed to decay to a top quark and the lightest supersymmetric particle (LSP). The data are found to be consistent with standard model expectations. Top squark masses between 230 GeV and 440 GeV are excluded with 95% confidence for massless LSPs, and top squark masses around 400 GeV are excluded for LSP masses up to 125 GeV.

Search for a supersymmetric partner to the top quark in final states with jets and missing transverse momentum at sqrt[s] = 7 TeV with the ATLAS detector

A search for direct pair production of supersymmetric top squarks (t(1)) is presented, assuming the t(1) decays into a top quark and the lightest supersymmetric particle, χ(1)(0), and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted standard model background of 13.5(-3.6)(+3.7)(4.4(-1.3)(+1.7)) events in two signal regions based on ∫Ldt = 4.7 fb(-1) of pp collision data taken at sqrt[s] = 7 TeV with the ATLAS detector at the LHC. An exclusion region in the t(1) versus χ(1)(0) mass plane is evaluated: 370<m(t)(1)}<465 GeV is excluded for m(χ)(1)(0) ~ 0 GeV while m(t)(1) = 445 GeV is excluded for m(χ)(1)(0) ≤ 50 GeV.

A search for [Formula: see text] resonances with the ATLAS detector in 2.05 fb-1 of proton-proton collisions at [Formula: see text]

A search for top quark pair resonances in final states containing at least one electron or muon has been performed with the ATLAS experiment at the CERN Large Hadron Collider. The search uses a data sample corresponding to an integrated luminosity of 2.05 fb-1, which was recorded in 2011 at a proton-proton centre-of-mass energy of 7 TeV. No evidence for a resonance is found and limits are set on the production cross-section times branching ratio to [Formula: see text] for narrow and wide resonances. For narrow Z' bosons, the observed 95 % Bayesian credibility level limits range from 9.3 pb to 0.95 pb for masses in the range of mZ'=500 GeV to mZ'=1300 GeV. The corresponding excluded mass region for a leptophobic topcolour Z' boson (Kaluza-Klein gluon excitation in the Randall-Sundrum model) is mZ'<880 GeV ([Formula: see text]).

Search for supersymmetry in events with three leptons and missing transverse momentum in √[s]=7 TeV pp collisions with the ATLAS detector

A search for the weak production of charginos and neutralinos decaying to a final state with three leptons (electrons or muons) and missing transverse momentum is presented. The analysis uses 2.06 fb(-1) of √[s]=7 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with standard model expectations in two signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric and simplified models. For the simplified models, degenerate lightest chargino and next-to-lightest neutralino masses up to 300 GeV are excluded for mass differences from the lightest neutralino up to 300 GeV.

Search for lepton flavour violation in the eμ continuum with the ATLAS detector in [Formula: see text]pp collisions at the LHC

This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark ([Formula: see text]) in the e±μ∓ continuum using 2.1 fb-1 of data collected by the ATLAS detector in [Formula: see text]pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 % C.L. are calculated as a function of the scalar top mass ([Formula: see text]). The upper limits on the production cross section for pp→eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for [Formula: see text] to 30 fb for [Formula: see text].

Measurement of the ZZ production cross section and limits on anomalous neutral triple gauge couplings in proton-proton collisions at sqrt[s] = 7 TeV with the ATLAS detector

A measurement of the ZZ production cross section in proton-proton collisions at sqrt[s] = 7 TeV using data corresponding to an integrated luminosity of 1.02 fb(-1) recorded by the ATLAS experiment at the LHC is presented. Twelve events containing two Z boson candidates decaying to electrons and/or muons are observed, with an expected background of 0.3 ± 0.3(stat)(-0.3)(+0.4)(syst) events. The cross section measured in a phase-space region with good detector acceptance and for dilepton masses within the range 66 to 116 GeV is σ(ZZ → ℓ+ ℓ- ℓ+ ℓ-)(fid) = 19.4(-5.2)(+6.3)(stat)(-0.7)(+0.9)(syst) ± 0.7(lumi) fb. The resulting total cross section for on-shell ZZ production, σ(ZZ)(tot) = 8.5(-2.3)(+2.7)(stat)(-0.3)(+0.4)(syst) ± 0.3(lumi) pb, is consistent with the standard model expectation of 6.5(-0.2)(+0.3) pb calculated at the next-to-leading order in QCD. Limits on anomalous neutral triple gauge boson couplings are derived.

Enhanced alveolar bone loss in a model of non-invasive periodontitis in rice rats

OBJECTIVE

The rice rat (Oryzomys palustris) develops periodontitis-like lesions when fed a diet rich in sucrose and casein (H-SC). We aimed to establish whether this model can accurately mimic the development of human periodontitis.

MATERIALS AND METHODS

For this purpose, 28-day-old rice rats (15/group) were assigned to standard (STD) or H-SC diets and sacrificed after 6, 12, and 18 weeks. Jaws were processed for morphometric, histometric, histologic, histomorphometric, and micro-CT analyses.

RESULTS

We found a progressive increase in horizontal alveolar bone loss (ABL) with age in maxillae of rats fed the STD diet as determined by morphometry. The H-SC diet exacerbated horizontal ABL at the palatal surface at 12 and 18 weeks. Furthermore, increased vertical ABL was detected in mandibles and maxillae of rats fed the H-SC diet for 12 and/or 18 weeks by histometry and micro-CT. Remarkably, the H-SC diet significantly increased bone remodeling at the interproximal alveolar bone of mandibles from rats fed for 6 weeks, but not in those fed for longer periods.

CONCLUSIONS

These findings indicate that the H-SC diet induced a transient increase in alveolar bone remodeling, which is followed by ABL characteristic of moderate periodontitis.

Protective Responses in Tuberculosis: Induction of Genes for Interferon-gamma and Cytotoxicity by Mycobacterium tuberculosis and During Human Tuberculosis

The host effector mechanisms against Mycobacterium tuberculosis infection are not well understood, and this remains a problem in the development of new vaccines and immunotherapies in tuberculosis (TB). Here, we studied the expression of genes for interferon gamma (IFN-gamma) and molecules involved in lymphocyte-mediated cytotoxicity [granzyme B (grzB), perforin, granulysin and Fas ligand (FasL)] against M. tuberculosis-infected macrophages. The kinetics of expression of these molecules were first established in peripheral blood mononuclear cells (PBMC) of healthy donors, and then investigated in TB patients with and without HIV-1 coinfection and appropriate control groups. We found that only IFN-gamma and grzB were induced by M. tuberculosis in PBMC from healthy purified protein derivative skin test reactive subjects. However, expression of neither gene nor IFN-gamma protein correlated with intracellular M. tuberculosis growth containment by macrophages. Mycobacterium tuberculosis induction of IFN-gamma, but not grzB, mRNA expression was significantly lower (P < 0.03) in TB patients as compared with healthy subjects.

Gestational surrogacy: a feasible option for patients with Rokitansky syndrome

Rokitansky syndrome is a developmental defect characterized by agenesis of the uterus and vagina but normal gonads and secondary sexual characters. It is not commonly transmitted as a dominant genetic trait. Surrogacy, which is legally and ethically accepted in the UK and other countries, has made it possible for the patients with this syndrome to have their own genetic children. Six patients with Rokitansky syndrome underwent 11 ovarian stimulation cycles that resulted in 11 fresh and three frozen embryo transfer procedures into six prospective surrogate mothers. Both commissioning and surrogate couples were properly screened and counselled and their treatment was approved by the clinic internal review committee (ethics committee). The treatment cycles resulted in six clinical pregnancies (42.9% pregnancy rate per embryo transfer and 54.5% per oocyte retrieval) and three live births (21. 4% per embryo transfer, 27.3% per retrieval and 50% per patient). Gestational surrogacy is a viable treatment for patients with Rokitansky syndrome. Such patients should be well informed and supported to be able to have a family using their own genetic gametes.

Effectiveness of a low-fat vegetarian diet in altering serum lipids in healthy premenopausal women

Few controlled trials have studied cholesterol-lowering diets in premenopausal women. None has examined the cholesterol-lowering effect of a low-fat vegetarian diet, which, in other population groups, leads to marked reductions in serum cholesterol concentrations and, in combination with other life-style changes, a regression of atherosclerosis. We tested the hypothesis that a low-fat, vegetarian diet significantly reduces serum total and low-density lipoprotein (LDL) cholesterol concentrations in premenopausal women. In a crossover design, 35 women, aged 22 to 48, followed a low-fat vegetarian diet deriving approximately 10% of energy from fat for 2 menstrual cycles. For 2 additional cycles, they followed their customary diet while also taking a "supplement" (placebo) pill. Serum lipid concentrations were assessed at baseline and during each intervention phase. Mean serum LDL, high-density lipoprotein (HDL), and total cholesterol concentrations decreased 16. 9%, 16.5%, and 13.2%, respectively, from baseline to the intervention diet phase (p<0.001), whereas mean serum triacylglycerol concentration increased 18.7% (p<0.01). LDL/HDL ratio remained unchanged. Thus, in healthy premenopausal women, a low-fat vegetarian diet led to rapid and sizable reductions in serum total, LDL, and HDL cholesterol concentrations.

Depressed T-cell interferon-gamma responses in pulmonary tuberculosis: analysis of underlying mechanisms and modulation with therapy

Immunological and clinical profiles were evaluated in 2 groups: human immunodeficiency virus (HIV)-uninfected and HIV-infected patients, with newly diagnosed pulmonary tuberculosis (TB), and tuberculin-skin-test-reactive healthy control subjects. HIV-uninfected patients with TB were also followed up longitudinally during and after chemotherapy. At the time of diagnosis, purified protein derivative (PPD)-stimulated production of interferon (IFN)-gamma by peripheral blood mononuclear cells from TB patients was depressed, compared with that of healthy control subjects, whereas levels of transforming growth factor (TGF)-beta and interleukin (IL)-10 were increased. In longitudinal studies, PPD stimulated production of IL-10 and TGF-beta returned to baseline by 3 months, whereas IFN-gamma production remained depressed for at least 12 months. These data indicate that the immunosuppression of TB is not only immediate and apparently dependent (at least in part) on immunosuppressive cytokines early during the course of Mycobacterium TB infection but is also long lasting, presumably relating to a primary abnormality in T-cell function.

Drug tolerance in Mycobacterium tuberculosis

Although Mycobacterium tuberculosis is eradicated rapidly during therapy in some patients with pulmonary tuberculosis, it can persist for many months in others. This study examined the relationship between mycobacterial drug tolerance (delayed killing in vitro), persistence, and relapse. It was performed with 39 fully drug-susceptible isolates from a prospective trial of standard short-course antituberculous therapy with sputum smear-positive, human immunodeficiency virus-uninfected subjects with pulmonary tuberculosis in Brazil and Uganda. The rate of killing in vitro was determined by monitoring the growth index (GI) in BACTEC 12B medium after addition of drug to established cultures and was measured as the number of days required for 99% sterilization. Drugs differed significantly in bactericidal activity, in the following order from greatest to least, rifampin > isoniazid-ethambutol > ethambutol (P < 0.001). Isolates from subjects who had relapses (n = 2) or in whom persistence was prolonged (n = 1) were significantly more tolerant of isoniazid-ethambutol and rifampin than isolates from other subjects (P < 0.01). More generally, the duration of persistence during therapy was predicted by strain tolerance to isoniazid and rifampin (P = 0.012 and 0.026, respectively). Tolerance to isoniazid-ethambutol and tolerance to rifampin were highly correlated (P < 0.001). Tolerant isolates did not differ from others with respect to the MIC of isoniazid; the rate of killing of a tolerant isolate by isoniazid-ethambutol was not increased at higher drug concentrations. These observations suggest that tolerance may not be due to drug-specific mechanisms. Tolerance was of the phenotypic type, although increased tolerance appeared to emerge after prolonged drug exposure in vivo. This study suggests that drug tolerance may be an important determinant of the outcome of therapy for tuberculosis.

Formal properties of the circadian and photoperiodic systems of Japanese quail: phase response curve and effects of T-cycles

A role for the circadian system in photoperiodic time measurement in Japanese quail is controversial. The authors undertook studies of the circadian and photoperiodic system of Japanese quail to try to identify a role for the circadian system in photoperiodic time measurement. The circadian studies showed that the circadian system acts like a low-amplitude oscillator: It is readily reset by light without significant transients, has a Type 0 phase response curve (PRC), and has a large range of entrainment. In fact, a cycle length that is often used in resonance protocols (LD 6:30) is within the range of entrainment. The authors employed T-cycle experiments; that is, LD cycles with 6- and 14-h photoperiods and period lengths ranging from 18 to 36 h to test for circadian involvement in photoperiodic time measurement. The results did not give evidence for circadian involvement in photoperiodic time measurement: T-cycles utilizing 6-h photoperiods were uniformly noninductive (that is, did not stimulate the reproductive system), whereas T-cycles utilizing 14-h photoperiods were inductive (stimulatory). A good match was observed between the phase-angles exhibited on the T-cycles employing 6-h photoperiods and the predicted phase-angles calculated from a PRC generated from 6-h light pulses.

Eye and gonad: role in the dual-oscillator circadian system of female Japanese quail

Experiments were conducted to determine the anatomic and physiological basis of the dual-oscillator circadian system of female Japanese quail. After blocking of ocular light perception by eye-patching, the circadian body temperature rhythm dissociates into two circadian components in continuous lighting (LL). One component free runs with a period significantly shorter than 24 h [mean period (tau) = 22.7 h] and is driven by an ocular pacemaker, whereas the other component free runs with a period significantly longer than 24 h (tau = 26.3 h). The long free-running rhythm is driven by the same circadian clock that drives the circadian rhythm of ovulation. The expression of the long free-running rhythm in LL depends on the presence of the ovary: body temperature rhythmicity is abolished by ovariectomy. The two free-running oscillators in eye-patched birds showed evidence of mutual interaction. Significantly, the phase relationships that occur as the two oscillators interact can determine whether or not ovulation occurs. The results are discussed in terms of an "internal coincidence" mechanism for photoperiodic time measurement.

Anti-endometrial antibodies in women measured by an enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent assay (ELISA) was developed to measure anti-endometrial antibody concentrations in the serum of women with endometriosis. Pooled cytosolic protein extracts from the endometrial gland cells of 10 women were used as an antigen source. Serum samples were obtained from women with endometriosis before (n = 51) and after 6 months treatment with danazol or nafarelin (n = 30). Control sera came from women with a normal pelvis at laparoscopy, performed for sterilization (n = 23) or the investigation of pain and/or infertility (n = 22), 13 women with Rokitansky syndrome, and 10 umbilical cord bloods and adult males. There were no significant differences in serum anti-endometrial antibody concentrations before and after treatment, or between women with endometriosis and without endometriosis. Concentrations were lower in male and cord blood serum than in female's serum (P < 0.0001). We conclude that the ELISA is not a useful diagnostic tool for endometriosis unless more specific antigens can be isolated.

Generalized immune activation in pulmonary tuberculosis: co-activation with HIV infection

Parameters of immune activation/differentiation were studied in a group of newly diagnosed HIV- and HIV+ pulmonary tuberculosis (TB) patients. Compared with controls, HLA-DR expression on both CD4 and CD8 T cells from the HIV- TB patients was approximately doubled; HLA-DR on T cells from the HIV+ group was tripled. The monocytes from both groups of patients expressed abnormally high levels of the Fc gamma receptors I and III. Serum levels of tumour necrosis factor-alpha (TNF-alpha), neopterin and beta 2-microglobulin were increased in HIV- and even more so in HIV+ TB patients. The expression of HLA-DR on T cell subsets and of Fc gamma R on monocytes correlated with each other, but not with serum activation markers. This pattern of non-specific activation during TB infection may be associated with enhanced susceptibility to HIV infection.

The circadian rhythm of thermoregulation in Japanese quail: III. Effects of melatonin administration

Recent studies indicate that the circadian pacemakers in the eyes of Japanese quail are coupled to the rest of the circadian system by both neural and hormonal outputs. The effects of exogenous melatonin administration on circadian body temperature and activity rhythms of quail were tested to determine whether melatonin could be the hormonal link involved. Continuous melatonin administration caused arrhythmicity or period changes in the body temperature and activity rhythms of pinealectomized and sham-pinealectomized birds held in constant darkness and also significantly decreased the amplitude of the body temperature rhythms of normal birds held on light:dark 12:12. Further, melatonin entrained the body temperature and activity rhythms of normal birds when administered daily via the drinking water. The results show that melatonin can affect the circadian system of quail and support the hypothesis that melatonin is importantly involved in linking pacemakers in the eyes to the rest of the circadian system.

The circadian rhythm of thermoregulation in Japanese quail. II. Multioscillator control

Most biochemical, physiological, and behavioral processes in vertebrates show significant daily rhythms. Under constant conditions, these rhythms exhibit an endogenous periodicity around 24 h showing that they are driven by an internal circadian clock. In Japanese quail, the circadian clock driving activity and body temperature rhythms is functionally organized as a dual-oscillator system. Under certain conditions, such as switching birds from light:dark (LD) 12:12 to continuous darkness (DD), the body temperature rhythm splits into two circadian components that free-run independently before recoupling in a normal phase-relationship. The behavior of the activity rhythm parallels that of the body temperature rhythm, supporting the hypothesis that both rhythms are driven by the same set of oscillators. In some instances, recoupling fails to occur and birds continue to exhibit two circadian components that free-run independently. Dual-oscillator control of body temperature was observed in normal birds, pinealectomized birds, and optic nerve sectioned birds. However, birds were rendered arrhythmic by complete eye removal. It is proposed that the central circadian system (suprachiasmatic nuclei?) acts as a complex pacemaker that is functionally organized as two sets of oscillators and that circadian input from the eyes is necessary to preserve the integrity of this complex pacemaker.

An updated review of the clinical development of coumarin (1,2-benzopyrone) and 7-hydroxycoumarin

Several authors have demonstrated that coumarin (1,2-benzopyrone) in combination with cimetidine can produce objective antitumor responses in some patients with advanced renal cell carcinoma. The purpose of this report is to review the clinical development of coumarin, with or without cimetidine, with special reference to renal cell carcinoma (RCC). Previously unpublished data concerning the survival of a population of patients with RCC, who were treated on a phase I trial of coumarin and cimetidine, are presented. The rationale and study design of an active randomized, double-blinded, placebo-controlled trial of coumarin for RCC are discussed. A progress report is given for an ongoing phase I trial of oral 7-hydroxycoumarin, the major human metabolite of coumarin.

Anti-Mycobacterium avium activity of quinolones: in vitro activities

The MICs of 88 quinolones against 14 selected reference and clinical strains of Mycobacterium avium-M. intracellular complex were determined. Agents tested included ciprofloxacin, sparfloxacin (PD 131501), and 86 other experimental quinolones. Test strains were selected to represent various susceptibilities to ciprofloxacin and other drug resistance profiles. MICs were determined by the microdilution method in 7HSF broth, with incubation for 14 days at 35 degrees C. The results showed 25 of the quinolones to be active against the strains, with MICs for 90% of the strains (MIC90s) of 2 to 32 micrograms/ml. Ten of these compounds had activities equivalent to or greater than that of ciprofloxacin. The most active compound was PD 125354, with an MIC50 of 0.5 micrograms/ml and an MIC90 of 2 micrograms/ml; comparable values for ciprofloxacin were 4 and 8 micrograms/ml, respectively. The next most active compounds, with MIC90s of 4 micrograms/ml, were sparfloxacin (PD 131501), PD 123982, PD 135144, and PD 119421. MIC90s of PD 131575, PD 126889, PD 122642, PD 139586, and PD 143289 were 8 micrograms/ml. Further evaluation of the most active agents is warranted, as is assessment of structure-activity relationships of active and inactive agents to elucidate the active portions of the compounds and to lead to the development of compounds with enhanced activity.

Mode of antiviral action of penciclovir in MRC-5 cells infected with herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus

The metabolism and mode of action of penciclovir [9-(4-hydroxy-3-hydroxymethylbut-1-yl)guanine; BRL 39123] were studied and compared with those of acyclovir. In uninfected MRC-5 cells, low concentrations of the triphosphates of penciclovir and acyclovir were occasionally just detectable, the limit of detection being about 1 pmol/10(6) cells. In contrast, in cells infected with either herpes simplex virus type 2 (HSV-2) or varicella-zoster virus (VZV), penciclovir was phosphorylated quickly to give high concentrations of the triphosphate ester. Following the removal of penciclovir from the culture medium, penciclovir-triphosphate remained trapped within the cells for a long time (half-lives, 20 and 7 h in HSV-2- and VZV-infected cells, respectively). In HSV-2-infected cells, acyclovir was phosphorylated to a lesser extent and the half-life of the triphosphate ester was only 1 h. We were unable to detect any phosphates of acyclovir in VZV-infected cells. (S)-Penciclovir-triphosphate inhibited HSV-1 and HSV-2 DNA polymerase competitively with dGTP, the Ki values being 8.5 and 5.8 microM, respectively, whereas for acyclovir-triphosphate, the Ki value was 0.07 microM for the two enzymes. Both compounds had relatively low levels of activity against the cellular DNA polymerase alpha, with Ki values of 175 and 3.8 microM, respectively. (S)-Penciclovir-triphosphate did inhibit DNA synthesis by HSV-2 DNA polymerase with a defined template-primer, although it was not an obligate chain terminator like acyclovir-triphosphate. These results provide a biochemical rationale for the highly selective and effective inhibition of HSV-2 and VZV DNA synthesis by penciclovir and for the greater activity of penciclovir than that of acyclovir when HSV-2-infected cells were treated for a short time.

Risk factors for HIV infection in homosexual men: the Cleveland men's study of risks in a low-prevalence area

Detailed questionnaires concerning alcohol and drug use, sexual practices, and medical history were completed by 301 homosexual men living in the Cleveland metropolitan area. Their sera were subsequently tested for antibodies to the human immunodeficiency virus. Fifty-six (18.6%) were seropositive. In a univariate analysis, age, drug use, and four specific sexual practices were associated with seropositivity. In a multiple logistic regression analysis, intravenous drug use and receptive anal-genital sex remained independent predictors of seropositivity.

Polycystic ovary syndrome in a virilised, premenarcheal girl

A premenarcheal girl aged 12 years presented with an abdominopelvic mass and virilisation. A large ovarian cyst was removed at laparotomy. A histological diagnosis of polycystic ovarian syndrome was made, with no evidence of an associated masculinising tumour.

Cell-mediated immune responses in human infection with Onchocerca volvulus

Mechanisms involved in modulation of the immune response in persons with chronic Onchocerca volvulus infection are poorly understood. In this study in vitro reactivity of PBMC to O. volvulus antigen (Ovag), streptolysin O (SL-O) and the mitogen PHA was tested in 62 infected individuals (INF), 17 persons living in the endemic area with exposure to the infection, but with no detectable infection (END), and 7 healthy controls (CTRL) in Liberia, West Africa. Mean blastogenic responses to Ovag were minimal and did not differ between the groups. There was, however, heterogenous reactivity to Ovag in the INF and END. For example, individuals with a history of therapy, and half of those less than 17 yr old who were tested, showed high responses. No significant differences in the response to SL-O or PHA were detected between the groups. IL-2 production in response to Ovag was minimal in the majority of infected subjects. Exogenous IL-2 was found to cause a significant increase in mean responses to Ovag and SL-O in INF and END only. Similarly, Ovag did not stimulate IL-1 production in most INF, whereas stimulation with LPS led to significantly greater production of IL-1. Depletion of plastic and nylon wool adherent cells did not increase responses to parasite-related antigen in INF, END or CTRL; however, responses to SL-O were augmented in INF, an effect that was also observed in CTRL. Finally, depletion of CD8 or CD16 cells in INF by C lysis did not increase blastogenic responses. These results indicate that cell-mediated immunity to parasite-related Ag as reflected in lymphocyte responses in vitro is diminished in infected individuals, and that this may be caused by defects in T cell activation.

Cell-mediated immune responses in human infection with Onchocerca volvulus

Mechanisms involved in modulation of the immune response in persons with chronic Onchocerca volvulus infection are poorly understood. In this study in vitro reactivity of PBMC to O. volvulus antigen (Ovag), streptolysin O (SL-O) and the mitogen PHA was tested in 62 infected individuals (INF), 17 persons living in the endemic area with exposure to the infection, but with no detectable infection (END), and 7 healthy controls (CTRL) in Liberia, West Africa. Mean blastogenic responses to Ovag were minimal and did not differ between the groups. There was, however, heterogenous reactivity to Ovag in the INF and END. For example, individuals with a history of therapy, and half of those less than 17 yr old who were tested, showed high responses. No significant differences in the response to SL-O or PHA were detected between the groups. IL-2 production in response to Ovag was minimal in the majority of infected subjects. Exogenous IL-2 was found to cause a significant increase in mean responses to Ovag and SL-O in INF and END only. Similarly, Ovag did not stimulate IL-1 production in most INF, whereas stimulation with LPS led to significantly greater production of IL-1. Depletion of plastic and nylon wool adherent cells did not increase responses to parasite-related antigen in INF, END or CTRL; however, responses to SL-O were augmented in INF, an effect that was also observed in CTRL. Finally, depletion of CD8 or CD16 cells in INF by C lysis did not increase blastogenic responses. These results indicate that cell-mediated immunity to parasite-related Ag as reflected in lymphocyte responses in vitro is diminished in infected individuals, and that this may be caused by defects in T cell activation.