The fascinating tribological phenomenon of carbon nanotubes (CNTs) observed at the nanoscale was confirmed in our numerous macroscale experiments. We designed and employed CNT-containing ...nanolubricants strictly for polymer lubrication. In this paper, we present the experiment characterising how the CNT structure determines its lubricity on various types of polymers. There is a complex correlation between the microscopic and spectral properties of CNTs and the tribological parameters of the resulting lubricants. This confirms indirectly that the nature of the tribological mechanisms driven by the variety of CNT-polymer interactions might be far more complex than ever described before. We propose plasmonic interactions as an extension for existing models describing the tribological roles of nanomaterials. In the absence of quantitative microscopic calculations of tribological parameters, phenomenological strategies must be employed. One of the most powerful emerging numerical methods is machine learning (ML). Here, we propose to use this technique, in combination with molecular and supramolecular recognition, to understand the morphology and macro-assembly processing strategies for the targeted design of superlubricants.
BACKGROUND:Urine biomarkers have helped identify persons at risk for progressing to kidney disease in the setting of HIV infection. We explored factors associated with changes in 3 urine biomarkers ...over 10 years among women living with HIV.
METHODS:Prospective cohort of 294 HIV-infected women from the multicenter Womenʼs Interagency HIV Study. Predictors included HIV viral and immunological parameters, comorbid conditions, and health-related behaviors. Outcomes were patterns of changes of urine interleukin-18 (IL-18), albumin-to-creatinine ratio (ACR), and alpha-1-microglobulin (α1m) over 10 years. We used quantile regression to examine patterns of change in each urine biomarker during follow-up and multivariable analysis of variance regression to identify predictors of biomarker changes.
RESULTS:Over 10 years, the median concentrations of IL-18 declined from 120 to 64 pg/mL, α1m rose from 0.7 to 1.5 ng/mL, and ACR remained stable (9–8 mg/g). In multivariate analyses, the strongest predictors of increases in IL-18 were higher baseline body mass index, increase in waist circumference, higher follow-up HIV viral load, lower follow-up CD4 cell count, hepatitis C virus (HCV) coinfection, and higher follow-up high density lipoprotein cholesterol. Predictors of increasing concentration of α1m were lower CD4 cell counts, higher diastolic blood pressure, HCV coinfection, and smoking. Finally, determinants of ACR increases during follow-up were higher follow-up diastolic blood pressure, HCV coinfection, higher follow-up HIV viral load, and triglyceride concentration.
CONCLUSIONS:Over 10 years, HIV disease status had different associations with each urine biomarker under study. Overall, the associations with changes in each biomarker support research into their use for longitudinal monitoring of kidney health.
•Nanocomposite consisting of multi-walled carbon nanotubes and kraft lignin was prepared and characterized.•The characterization confirmed uniform, dense packing of the biopolymer on the surface of ...the nanotubes.•The nanocomposite can effectively store electric charge on the basis of the double layer capacitance and red-ox reactions.
The results of this study demonstrate the spectral, microscopic and electrochemical properties of multi-walled carbon nanotubes (CNTs) surface-functionalized with kraft lignin (KL). XPS and FT-IR spectroscopy show that the biomolecule is effectively adsorbed on the surface of CNTs, leading to an increase in oxygen content and the appearance of spectral features characteristic of highly oxidized polyphenolic compounds. The presence of KL makes CNTs easily dispersible in organic (DMSO) and aqueous (0.1M ammonia) solutions. Microscopic analysis (SEM and AFM) confirms the effective debundling of CNTs and the presence of densely packed globular structures on the surface of individual nanotubes. Deposition of the CNT/KL composite on the surface of a gold electrode facilitates its electrochemical characterization. This reveals that the CNT-supported biomolecule exhibits persistent reversible redox behavior attributed to KL-derived quinone moieties. Therefore the reversible redox activity of the lignin adsorbate can be utilized for charge storage, providing more than a 100% increase in the capacitance of KL-modified carbon nanotubes compared with unmodified ones.
Problem
Stability over time of systemic and mucosal immunity and their associations with bacterial vaginosis (BV) and HIV‐specific parameters were assessed.
Method of Study
Immune mediators and HIV ...viral load in plasma and cervicovaginal lavage (CVL), E. coli inhibition, and Nugent score were measured at three semiannual visits among 94 participants in the Women's Interagency HIV Study. Mixed models identified the factors associated with immune mediators.
Results
There was higher E. coli inhibition and lower inflammation over time in the genital tract and systemically. BV was consistently associated with higher CVL inflammatory mediators and lower CVL E. coli inhibition. HIV‐infected women with higher CD4 counts had lower systemic and genital inflammatory mediators, and genital HIV shedding was associated with higher CVL inflammatory mediators. Use of antiretroviral therapy (ART) was associated with lower plasma and CVL mediators, but higher E. coli inhibition.
Conclusion
HIV and BV are linked to inflammation, and ART may be associated with improved vaginal health.
Background APOL1 genotype is associated with advanced kidney disease in African Americans, but the pathogenic mechanisms are unclear. Here, associations of APOL1 genotype with urine biomarkers of ...glomerular and tubular injury and kidney function decline were evaluated. Study Design Observational study. Setting & Participants 431 human immunodeficiency virus (HIV)-infected African American women enrolled in Women’s Interagency HIV Study (WIHS). Predictor APOL1 genotype. Outcomes Albumin-creatinine ratio (ACR), 4 tubular injury biomarkers (interleukin 18 IL-18, kidney injury molecule 1 KIM-1, neutrophil gelatinase-associated lipocalin NGAL, and α1 -microglobulin A1M), and kidney function estimated using the CKD-EPI cystatin C equation. Measurements Participants were genotyped for APOL1 single-nucleotide polymorphisms rs73885319 (G1 allele) and rs71785313 (G2 allele). Urine biomarkers were measured using stored samples from 1999-2000. Cystatin C was measured using serum collected at baseline and 4- and 8-year follow-ups. Results At baseline, ACRs were higher among 47 women with 2 APOL1 risk alleles versus 384 women with 0/1 risk allele (median, 24 vs 11 mg/g; P < 0.001). Compared with women with 0/1 risk allele, women with 2 risk alleles had 104% higher ACRs (95% CI, 29-223 mg/g) and 2-fold greater risk of ACR > 30 (95% CI, 1.17-3.44) mg/g after multivariable adjustment. APOL1 genotype showed little association with urine IL-18:Cr ratio, KIM-1:Cr ratio, and NGAL:Cr ratio (estimates of −5% 95% CI, −24% to 18%, −20% 95% CI, −36% to −1%, and 10% 95% CI, −26% to 64%, respectively) or detectable urine A1M (prevalence ratio, 1.13; 95% CI, 0.65-1.97) in adjusted analyses. Compared with women with 0/1 allele, women with 2 risk alleles had faster eGFR decline, by 1.2 (95% CI, 0.2 to 2.2) mL/min/1.73 m2 per year, and 1.7- and 3.4-fold greater rates of incident chronic kidney disease (95% CI, 1.1 to 2.5) and 10% annual eGFR decline (95% CI, 1.7 to 6.7), respectively, with minimal attenuation after adjustment for glomerular and tubular injury biomarker levels. Limitations Results may not be generalizable to men. Conclusions Among HIV-infected African American women, APOL1 -associated kidney injury appears to localize to the glomerulus, rather than the tubules.
In the recent years industrial applications of carbon allotropes such as carbon nanotubes (CNTs) and graphene have been tested extensively, thus justifying research on the environmental impact these ...materials have. In the current paper we compare EDS spectroscopy results of a cabin filter used in a car to a filter used in an air purifier inside a residential space. The contaminants adsorbed on the carbon nanoparticles trapped in both types of filters allows for determining of their source of origin demonstrating clearly the dominant role of non-road emissions in Poland. Finally we present the experimental study on the growth of plants on substrates intentionally enriched with CNTs.
Background. Inflammation persists in treated human immunodeficiency virus (HIV) infection and may contribute to an increased risk for non-AIDS-related pathologies. We investigated the correlation of ...cytokine responses with changes in CD4 T-cell levels and coinfection with hepatitis C virus (HCV) during highly active antiretroviral treatment (HAART). Methods. A total of 383 participants in the Women's Interagency HIV Study (212 with HIV monoinfection, 56 with HCV monoinfection, and 115 with HIV/HCV coinfection) were studied. HIV-infected women had <1000 HIV RNA copies/mL, 99.7% had >200 CD4 T 98% were receiving HAART at baseline. Changes in CD4 T-cell count between baseline and 2-4 years later were calculated. Peripheral blood mononudear cells (PBMCs) obtained at baseline were used to measure interleukin Iβ (IL-1β), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 12 (IL-12), and tumor necrosis factor α (TNF-α) responses to Toll-like receptor (TLR) 3 and TLR4 stimulation. Results. Undetectable HIV RNA (<80 copies/mL) at baseline and secretion of IL-10 by PBMCs were positively associated with gains in CD4 T-cell counts at follow-up. Inflammatory cytokines (IL-lβ, IL-6, IL-12, and TNF-α) were also produced in TLR-stimulated cultures, but only IL-10 was significantly associated with sustained increases in CD4 T-cell levels. This association was significant only in women with HIV monoinfection, indicating that HCV coinfection is an important factor limiting gains in CD4 T-cell counts, possibly by contributing to unbalanced persistent inflammation. Conclusions. Secreted IL-10 from PBMCs may balance the inflammatory environment of HIV, resulting in CD4 T-cell stability.
Background/Aims
Among individuals without human immunodeficiency virus (HIV), African Americans have lower spontaneous clearance of hepatitis C virus (HCV) than Caucasians, and women have higher ...clearance than men. Few studies report racial/ethnic differences in acute HCV in HIV infected, or Hispanic women. We examined racial/ethnic differences in spontaneous HCV clearance in a population of HCV mono- and co-infected women.
Methods
We conducted a cross sectional study of HCV seropositive women (897 HIV infected and 168 HIV uninfected) followed in the US multicenter, NIH-funded Women’s Interagency HIV Study (WIHS), to determine the association of race/ethnicity with spontaneous HCV clearance, as defined by undetectable HCV RNA at study entry.
Results
Among HIV and HCV seropositive women, 18.7 % were HCV RNA negative, 60.9 % were African American, 19.3 % Hispanic and 17.7 % Caucasian. HIV infected African American women were less likely to spontaneously clear HCV than Hispanic (OR 0.59, 95 % CI 0.38–0.93,
p
= 0.022) or Caucasian women (OR 0.57, 95 % CI 0.36–0.93,
p
= 0.023). Among HIV uninfected women, African Americans had less HCV clearance than Hispanics (OR 0.18, 95 % CI 0.07–0.48,
p
= 0.001) or Caucasians (OR 0.26, 95 % CI 0.09–0.79,
p
= 0.017). There were no significant differences in HCV clearance between Hispanics and Caucasians, among either HIV infected (OR 0.97, 95 % CI 0.57–1.66,
p
= 0.91) or uninfected (OR 1.45, 95 % CI 0.56–3.8,
p
= 0.45) women.
Conclusions
African Americans were less likely to spontaneously clear HCV than Hispanics or Caucasians, regardless of HIV status. No significant differences in spontaneous HCV clearance were observed between Caucasian and Hispanic women. Future studies incorporating IL28B genotype may further explain these observed racial/ethnic differences in spontaneous HCV clearance.
We determined the abilities of 10 technologies to detect and quantify a common drug-resistant mutant of human immunodeficiency virus type 1 (lysine to asparagine at codon 103 of the reverse ...transcriptase) using a blinded test panel containing mutant-wild-type mixtures ranging from 0.01% to 100% mutant. Two technologies, allele-specific reverse transcriptase PCR and a Ty1HRT yeast system, could quantify the mutant down to 0.1 to 0.4%. These technologies should help define the impact of low-frequency drug-resistant mutants on response to antiretroviral therapy.
PDF
