Peripheral blood CD4+CCR6+ compartment differentiates HIV-1 infected or seropositive elite controllers from long-term successfully treated individuals

HIV-1 infection induces a chronic inflammatory environment not restored by suppressive antiretroviral therapy (ART). As of today, the effect of viral suppression and immune reconstitution in people living with HIV-1 (PLWH) has been well described but not completely understood. Herein, we show how PLWH who naturally control the virus (PLWH_EC) have a reduced proportion of CD4⁺CCR6⁺ and CD8⁺CCR6⁺ cells compared to PLWH on suppressive ART (PLWH_ART) and HIV-1 negative controls (HC). Expression of CCR2 was reduced on both CD4⁺, CD8⁺ and classical monocytes in PLWH_EC compared to PLWH_ART and HC. Longer suppressive therapy, measured in the same patients, decreased number of cells expressing CCR2 on all monocytic cell populations while expression on CD8⁺ T cells increased. Furthermore, the CD4⁺CCR6⁺/CCR6^- cells exhibited a unique proteomic profile with a modulated energy metabolism in PLWH_EC compared to PLWH_ART independent of CCR6 status. The CD4⁺CCR6⁺ cells also showed an enrichment in proteins involved in apoptosis and p53 signalling in PLWH_EC compared to PLWH_ART, indicative of increased sensitivity towards cell death mechanisms. Collectively, this data shows how PLWH_EC have a unique chemokine receptor profile that may aid in facilitating natural control of HIV-1 infection.

Metabolic Perturbation Associated With COVID-19 Disease Severity and SARS-CoV-2 Replication

Viruses hijack host metabolic pathways for their replicative advantage. In this study, using patient-derived multiomics data and in vitro infection assays, we aimed to understand the role of key metabolic pathways that can regulate severe acute respiratory syndrome coronavirus-2 reproduction and their association with disease severity. We used multiomics platforms (targeted and untargeted proteomics and untargeted metabolomics) on patient samples and cell-line models along with immune phenotyping of metabolite transporters in patient blood cells to understand viral-induced metabolic modulations. We also modulated key metabolic pathways that were identified using multiomics data to regulate the viral reproduction in vitro. Coronavirus disease 2019 disease severity was characterized by increased plasma glucose and mannose levels. Immune phenotyping identified altered expression patterns of carbohydrate transporter, glucose transporter 1, in CD8⁺ T cells, intermediate and nonclassical monocytes, and amino acid transporter, xCT, in classical, intermediate, and nonclassical monocytes. In in vitro lung epithelial cell (Calu-3) infection model, we found that glycolysis and glutaminolysis are essential for virus replication, and blocking these metabolic pathways caused significant reduction in virus production. Taken together, we therefore hypothesized that severe acute respiratory syndrome coronavirus-2 utilizes and rewires pathways governing central carbon metabolism leading to the efflux of toxic metabolites and associated with disease severity. Thus, the host metabolic perturbation could be an attractive strategy to limit the viral replication and disease severity.

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COVID-19 disease severity was characterized by increased plasma glucose and mannose.

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Mannose is a strong biomarker of COVID-19 disease severity.

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Glycolysis and glutaminolysis are essential for virus replication.

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Blocking the metabolic pathways caused significant reduction in virus production.

Cell-type-resolved quantitative proteomics map of interferon response against SARS-CoV-2

The commonly used laboratory cell lines are the first line of experimental models to study the pathogenicity and performing antiviral assays for emerging viruses. Here, we assessed the tropism and cytopathogenicity of the first Swedish isolate of SARS-CoV-2 in six different human cell lines, compared their growth characteristics, and performed quantitative proteomics for the susceptible cell lines. Overall, Calu-3, Caco2, Huh7, and 293FT cell lines showed a high-to-moderate level of susceptibility to SARS-CoV-2. In Caco2 cells, the virus can achieve high titers in the absence of any prominent cytopathic effect. The protein abundance profile during SARS-CoV-2 infection revealed cell-type-specific regulation of cellular pathways. Type-I interferon signaling was identified as the common dysregulated cellular response in Caco2, Calu-3, and Huh7 cells. Together, our data show cell-type specific variability for cytopathogenicity, susceptibility, and cellular response to SARS-CoV-2 and provide important clues to guide future studies.

Utility of Proteomics in Emerging and Re-Emerging Infectious Diseases Caused by RNA Viruses

Emerging and re-emerging infectious diseases due to RNA viruses cause major negative consequences for the quality of life, public health, and overall economic development. Most of the RNA viruses causing illnesses in humans are of zoonotic origin. Zoonotic viruses can directly be transferred from animals to humans through adaptation, followed by human-to-human transmission, such as in human immunodeficiency virus (HIV), severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and, more recently, SARS coronavirus 2 (SARS-CoV-2), or they can be transferred through insects or vectors, as in the case of Crimean-Congo hemorrhagic fever virus (CCHFV), Zika virus (ZIKV), and dengue virus (DENV). At the present, there are no vaccines or antiviral compounds against most of these viruses. Because proteins possess a vast array of functions in all known biological systems, proteomics-based strategies can provide important insights into the investigation of disease pathogenesis and the identification of promising antiviral drug targets during an epidemic or pandemic. Mass spectrometry technology has provided the capacity required for the precise identification and the sensitive and high-throughput analysis of proteins on a large scale and has contributed greatly to unravelling key protein-protein interactions, discovering signaling networks, and understanding disease mechanisms. In this Review, we present an account of quantitative proteomics and its application in some prominent recent examples of emerging and re-emerging RNA virus diseases like HIV-1, CCHFV, ZIKV, and DENV, with more detail with respect to coronaviruses (MERS-CoV and SARS-CoV) as well as the recent SARS-CoV-2 pandemic.

Changes in protein and gene expression of angiotensin II receptors (AT1 and AT2) in aorta of diabetic and hypertensive rats

Diabetes and hypertension have been associated with cardiovascular diseases and stroke. Some reports have related the coexistence of hypertension and diabetes with increase in the risk of developing vascular complications. Recently some studies have shown results suggesting that in the early stages of diabetes and hypertension exist a reduced functional response to vasopressor agents like angiotensin II (Ang II), which plays an important role in blood pressure regulation mechanism through the activation of its AT1 and AT2 receptors. For that reason, the aim of this work was to study the gene and protein expression of AT1 and AT2 receptors in aorta of diabetic SHR and WKY rats. Diabetes was induced by the administration of streptozotocin (60 mg/kg i.p.). After 4 weeks of the onset of diabetes, the protein expression was obtained by western blot and the mRNA expression by RT-PCR. Our results showed that the hypertensive rats have a higher mRNA and protein expression of AT1 receptors than normotensive rats while the AT2 expression remained unchanged. On the other hand, the combination of diabetes and hypertension increased the mRNA and protein expression of AT1 and AT2 receptors significantly. In conclusion, our results suggest that diabetes with hypertension modifies the mRNA and protein expression of AT1 and AT2 receptors. However, the overexpression of AT2 could be associated with the reduction in the response to Ang II in the early stage of diabetes.

Volatile organic compounds in headspace over electrical components at 75 to 200°C - part 1. identification of constituents and emission rates

The identity and emission rates of volatile organic compounds (VOCs) in headspace vapors over electronic components were determined at temperatures from 75 to 200°C using gas chromatography/mass spectrometry. The emission of VOCs may provide a basis to detect the onset of the overheating of electronic components in confined atmospheres near electronic bays on airplanes and submarines before smoldering or ignition. VOCs found in headspace vapors over components, including resistors, capacitors, diodes, transistors, and insulation from wires of a transformer, were composed of simple mixtures of substances with 6 to 10 carbon number from chemical families including ketones, aldehydes, substituted benzenes, alcohols, and phenols. Composition of the vapors was characteristic but not exclusive of a particular electrical component, except for phenols and methylstyrene, which were found only in a single component. Emission rates were expressed as nanogram of chemical per gram of component per minute, and increased from a low of 0.001 ng/g-min for nonanal from transformer wire at 100°C to a maximum of 2.5 ng/g-min at 150°C for isophorone from a resistor. Patterns of persistence with repeated sampling of headspace for components at 200°C over 5 hr suggested that VOCs arose from impurities in plastics rather than from thermal decomposition of the polymer.

Ion mobility spectrometry of gas-phase ions from laser ablation of solids in air at ambient pressure

A mobility spectrometer was used to characterize gas-phase ions produced from laser ablation of solids in air at 100 degrees C and at ambient pressure with a beam focused to a diameter of <or=0.2 mm at energy of 6 mJ/pulse and wavelength of 266 nm. Metals, organic polymers, glass, graphite, and boron nitride exhibited characteristic mobility spectra with peaks at drift times between 8.75 and 12.5 ms (reduced mobility values of 2.19 to 1.53 cm(2)/Vs). Ion intensities increased initially and then decreased with repeated laser shots through drilling of the solid, and persistence of signal was proportional to hardness. A single comparatively narrow peak for negative ions was observed in mobility spectra for all materials and this was mass-identified as O(2)(-). These ions were formed in air from reactions of oxygen with electrons emitted from the ablation step. Positive ions ablated directly from the solid were masked in ion mobility spectrometry/mass spectrometry (IMS/MS) studies by ionization of moisture and impurities. Positive ions from solids were seen only in the IMS analyzer at elevated temperature and low moisture. Under such conditions, materials were classified from mobility spectra alone with principal component analysis.

Mobility resolution and mass analysis of ions from ammonia and hydrazine complexes with ketones formed in air at ambient pressure

Protonated ammonia and hydrazines (MH(+)) form complexes with ketones and the differences in masses and mobilities of the resulting ions, MH(+)(ketone)(n), are sufficient for separation in an ion mobility spectrometer at ambient pressure. The highest mass ion for any of the protonated molecules is obtained when the ketone is present at elevated concentrations in the supporting atmosphere of both the source and drift regions of the spectrometer so that an ion maintains a discrete composition and mobility. The sizes of the ion-molecule complexes were found to depend on the number of H atoms on the protonated nitrogen atom--four for ammonia, three for hydrazine, two for monomethylhydrazine, and one for 1,1-dimethylhydrazine, and the drift times of these ions were proportional to the size of the ion-molecule complex. Unexpected side products, including protonated hydrazones and azines, and associated ketone clusters, were isolated to a single drift tube containing ceramic parts and could not, from CID studies, be attributed to gas-phase ion chemistry. These findings illustrate that mobility resolution of ions in IMS and IMS/MS experiments can be enhanced through chemical modification of the supporting gas atmosphere without changes in the core ion.

Neural network recognition of chemical class information in mobility spectra obtained at high temperatures

A minimal neural network was applied to a large library of high-temperature mobility spectra drawn from 16 chemical classes including 154 substances with 2000 spectra at various concentrations. A genetic algorithm was used to create a representative subset of points from the mobility spectrum as input to a cascade-type back-propagation network. This network demonstrated that significant information specific to chemical class was located in the spectral region near the reactant ions. This network failed to generalize the solution to unfamiliar compounds necessitating the use of complete spectra in network processing. An extended back-propagation network classified unfamiliar chemicals by functional group with a mean for average values of 0.83 without sulfides and 0.79 with sulfides. Further experiments confirmed that chemical class information was resident in the spectral region near the reactant ions. Deconvolution of spectra demonstrated the presence of ions, merged with the reactant ion peaks that originated from introduced samples. The ability of the neural network to generalize the solution to unfamiliar compounds suggests that these ions are distinct and class specific.

Atmospheric pressure chemical ionization of fluorinated phenols in atmospheric pressure chemical ionization mass spectrometry, tandem mass spectrometry, and ion mobility spectrometry

Atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) for fluorinated phenols (C6H5-xFxOH Where x = 0-5) in nitrogen with Cl- as the reagent ion yielded product ions of M Cl- through ion associations or (M-H)- through proton abstractions. Proton abstraction was controllable by potentials on the orifice and first lens, suggesting that some proton abstraction occurs through collision induced dissociation (CID) in the interface region. This was proven using CID of adduct ions (M Cl-) with Q2 studies where adduct ions were dissociated to Cl- or proton abstracted to (M-H)-. The extent of proton abstraction depended upon ion energy and structure in order of calculated acidities: pentafluorophenol > tetrafluorophenol > trifluorophenol > difluorophenol. Little or no proton abstraction occurred for fluorophenol, phenol, or benzyl alcohol analogs. Ion mobility spectrometry was used to determine if proton abstraction reactions passed through an adduct intermediate with thermalized ions and mobility spectra for all chemicals were obtained from 25 to 200 degrees C. Proton abstraction from M Cl- was not observed at any temperature for phenol, monofluorophenol, or difluorophenol. Mobility spectra for trifluorophenol revealed the kinetic transformations to (M-H)- either from M Cl- or from M2 Cl- directly. Proton abstraction was the predominant reaction for tetra- and penta-fluorophenols. Consequently, the evidence suggests that proton abstraction occurs from an adduct ion where the reaction barrier is reduced with increasing acidity of the O-H bond in C6H5-xFxOH.

Digital anaesthesia through the flexor tendon sheath at the palmar level

Sixty five patients with various traumatic lesions of the fingers have been operated on under digital anaesthesia using 3 ml of 2% Mepivacaine injected into the flexor tendon sheath. The anaesthesia was adequate for surgery in all instances except in one patient. No complications were encountered with this technique. The authors studied the mechanism of action by dissecting a cadaveric hand after injecting a tracer (Methylene blue) in place of the local anaesthesia, suggesting, but not proving, that anaesthesia is achieved by blocking the nerve in the area of the injection.

Entry and egress of varicella virus blocked by same anti-gH monoclonal antibody

Varicella virus is one of the most reclusive human herpesviruses. The virus is not released from infected cultured cells. Rather, infectivity is transferred by fusion of contiguous cells. To further investigate this process, infected cells were viewed by scanning electron microscopy. Thousands of viral particles were observed in elongated clusters overlying the virus-induced syncytia. When virus-infected cells were covered postinfection with medium supplemented with a monoclonal antibody to glycoprotein gpIII (gH homolog), syncytial formation was completely blocked and no progeny viral particles were observed on the surface of the monolayer. Removal of the antibody was followed by rapid progression of cytopathic effect. Addition of antibody to other viral proteins did not alter the infection. Thus, a monoclonal antibody to a single viral determinant on glycoprotein gpIII (gH) can prevent syncytial formation postinfection and block progression of infectivity. Since the same monoclonal antibody can inhibit entry, this study greatly expands the role of antibody in the modulation of herpesvirus infection.

False aneurysm of a digital artery. A case report

Traumatic aneurysms of a digital artery are rare, and only 11 cases have been reported in the literature. This paper describes the aetiology, physical appearances, investigation and management of a false aneurysm of the digital artery of the left little finger.

Outlet-strut fracture and disc embolization in 27-mm and smaller Björk-Shiley convexo-concave valves: historical overview and 3 case reports

Outlet-strut fracture leading to primary failure of Björk-Shiley convexo-concave disc valves has only recently been reported in valves of 27-mm size and smaller. We now report an additional 3 cases of outlet strut failure in smaller convexo-concave valves, in a series of 899 implantations (overall incidence, 0.33%) of convexo-concave valves in various sizes and in 2 variant opening angles (60 degrees and 70 degrees ), during a 6-year period. All failures were confined to lots implanted during 1981 and 1982. We describe these 3 cases within the context of an historical overview of the Björk-Shiley tilting-disc valve, and propose methods of surgical intervention when this life-threatening complication arises.

Beta interferon production in primed and unprimed cells infected with human cytomegalovirus

Human cytomegalovirus induced beta interferon in cultures of human foreskin cells. The inhibitor was first released between 8 and 16 hours after infection, about 48 hours before progeny virus. In cultures infected with low concentrations of virus, interferon was produced as the infection spread, and then in amounts larger than expected. After infection with cytomegalovirus, cells which had been primed for 48 hours with purified beta interferon produced significantly more interferon than unprimed cells, and the interferon was produced earlier, between 2 and 8 hours after infection. CMV-induced interferon also was able to prime cells. The data suggest that the relatively large quantities of interferon detected in cultures infected with low concentrations of cytomegalovirus result from endogenous priming: those cells infected early first produce interferon which primes uninfected cells, then virus which induces the primed cells to produce interferon in relatively high concentrations.

Bactericidal effects of the neodymium:YAG laser: in vitro study

The effects of laser energy on three bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were studied utilizing the neodymium:YAG laser. Cell suspensions of each strain were divided into four groups. In group I, suspensions from each strain were exposed to laser energy densities of 555-3,333 J/cm2. In groups II and III, two artificial dyes, congo red or methylene blue, were added to the suspensions prior to lasing. In group IVa, no laser energy was used, and group IVb was used to measure the bactericidal thermal effects of the laser. It was concluded that: Low dosages of laser energy exceeding 1,667 J/cm2 resulted in a 2 to 8 log decline in the number of viable bacterial colonies in vitro. Compared to the other two bacterial strains, P aeruginosa was the most sensitive to YAG laser irradiation. Addition of methylene blue, a dark-colored dye, enhanced the bactericidal effects of the YAG laser as indicated by the significantly reduced viability of P aeruginosa after irradiation with 2,222 J/cm2.

Effects of varying intensities of laser energy on articular cartilage: a preliminary study

The effects of laser energy on articular cartilage were studied utilizing the neodymium YAG laser. Partial-thickness cartilage defects were surgically attempted in the femoral condyles of knee joints in guinea pigs. The defects were exposed to laser energy of varying intensities [group I, 25 J (5 W X 5 sec); group II, 75 J (15 W X 5 sec); group III, 125 J (25 W X 5 sec)]. A fourth group was studied, in which the defect was not lased. Animals were killed at weekly intervals from 1 to 6 weeks and the knee joints were subjected to histological analysis. At 5 weeks, the knees exposed to 25 and 75 J demonstrated a reparative process with chondral proliferation. The knees exposed to 125 J demonstrated fibrotic tissue and tissue necrosis that resulted in fibrosis. In the knees not exposed to laser energy, numerous foci of granulation tissue were present at all stages with the end point of healing being one of fibrosis with disorganized patchy cartilage islands.

Human cytomegalovirus persists in cells treated with interferon. Brief report

Human cytomegalovirus disappeared from cultures continuously exposed to interferon. When interferon was removed, high titers of virus reappeared. Cytomegalovirus was thus able to persist in potentially infectious form in cells protected by interferon.

Synthesis of human cytomegalovirus-specified RNA and protein in interferon-treated cells at early times after infection

In human fibroblast cells treated with interferon, cytomegalovirus-specified immediate early RNA was found associated with the polyribosomes at concentrations and size classes similar to the virus RNA found in non-treated cells, Interferon treatment inhibited the translation of the immediate early virus mRNA; the relative rate of virus-specified immediate early protein and antigen synthesis decreased with increasing concentrations of interferon. In addition, the relative amount of virus-specified RNA associated with the polyribosomes at early times after infection was significantly reduced by treatment of the cells with interferon. Inhibition of infectious virus production in interferon-treated cells was primarily due to inhibition of immediate early virus protein synthesis and secondarily to suppression of early virus RNA synthesis. The role of the virus-specified immediate early proteins in regulating subsequent virus gene expression is discussed.

Biological characteristics of cloned populations of herpes simplex virus types 1 and 2

By using cloned types 1 and 2 herpes simplex virus, obtained by selecting large and small plaques produced by material from human lesions, studies were performed to compare properties between preparations of each type. Regarding the rate of inactivation by ultraviolet light, no differences were found between the two antigenic types and none between the preparations obtained from either type. In contrast, type 1 preparations were found to be more readily inactivated at 45 C than type 2. Plaque size of cloned preparations changed by passage in cell culture. A broader range of plaque sizes was obtained, and average plaque size was larger. After 20 passages, preparations obtained from different types gave rise to one of three kinds of cytopathic effect. The cytopathic effect produced by type 1 preparations remained as before 20 passages and consisted of round cells in a compact central mass. For type 2, two kinds of cytopathic effect were seen in cloned preparations. This consisted of aggregates of round cells (seen in preparations before 20 passages) or of large, loose aggregates of round cells of various sizes. Results from neutralization studies using virus before and after 20 passages in cell culture versus antisera prepared against live or ultraviolet-inactivated virus showed no differences between cloned preparations obtained from a given type.

Studies on persistent infections of tissue culture. VI. Reversible changes in Newcastle disease virus populations as a result of passage in L cells or chick embryos

Populations of the Victoria strain of Newcastle disease virus (NDV), reisolated from persistently infected L-cell cultures and passed twice in the embryonated hen's egg (NDV(L-E-2)), were found to differ strikingly from the original, chick embryo-adapted virus (NDV(o)). After exposure of L cells to NDV(o) at high multiplicities of infection, all cells became abortively infected; they produced only small aggregates of viral antigen and few, if any, infectious virus particles, but they yielded large amounts of interferon. No cytopathic effects (CPE) were noted, and the cultures survived readily as viral carriers. In contrast, NDV(L-E-2) yielded under similar conditions large quantities of viral antigen and infectious virus particles, but no detectable interferon, and the cultures were rapidly destroyed. This change in "virulence" was at least partially reversible by further serial passages of NDV(L-E-2) in chick embryos, as was evident from a consecutive decrease in CPE with a concomitant increasingly rapid recovery of the L-cell cultures, gradually diminishing yields of infectious viral progeny, and the returning of a capacity to induce interferon synthesis. Thus, NDV(L-E-16) resembled NDV(o) in many aspects, except for a less striking reduction in its ability to replicate in L cells. Although a selection of viral variants under the given sets of conditions has not been entirely excluded, the establishment of "avirulence" appears to be largely explained by a gradual accumulation of noninfectious, interferon-inducing components in the course of serial passages in the embryonated hen's egg, and the acquisition of "virulence" by a loss of these components. The evidence is as follows. (i) By a step-wise decrease in the dose of virus and restriction of the analyses to the first infectious cycle, a multiplicity of infection was ultimately reached for all "avirulent" populations at which infected cells produced normal yields of infectious viral progeny; i.e., the interferon-inducing components were diluted to noneffective levels. The lowest multiplicity which resulted in a measurable reduction in infectious virus replication was also the last one to induce detectable interferon synthesis. (ii) All viral clones derived from "avirulent" populations behaved like NDV(L-E-2) rather than like the parent viral suspensions, except that some of them elicited small amounts of interferon in L cells. The interferon-inducing components were reduced or lost in the cloning procedures. The nature of the interferon-inducing components has not been established. These components, which were neutralized by rabbit sera against "virulent" NDV(L-E-2) populations, may represent largely inactive or incomplete virus particles; however, the infectious virus-hemagglutinin ratios of "avirulent" populations were mostly of an order similar to those of "virulent" populations. The interferon-inducing components aborted the infectious process in cells simultaneously invaded by infectious virus particles. The implications of these findings are discussed.