Multichannel electrotactile feedback with spatial and mixed coding for closed-loop control of grasping force in hand prostheses

Providing somatosensory feedback to the user of a myoelectric prosthesis is an important goal since it can improve the utility as well as facilitate the embodiment of the assistive system. Most often, the grasping force was selected as the feedback variable and communicated through one or more individual single channel stimulation units (e.g., electrodes, vibration motors). In the present study, an integrated, compact, multichannel solution comprising an array electrode and a programmable stimulator was presented. Two co ding schemes (15 levels), spatial and mixed (spatial and frequency) modulation, were tested in able-bodied subjects, psychometrically and in force control with routine grasping and force tracking using real and simulated prosthesis. The results demonstrated that mixed and spatial coding, although substantially different in psychometric tests, resulted in a similar performance during both force control tasks. Furthermore, the ideal, visual feedback was not better than the tactile feedback in routine grasping. To explain the observed results, a conceptual model was proposed emphasizing that the performance depends on multiple factors, including feedback uncertainty, nature of the task and the reliability of the feedforward control. The study outcomes, specific conclusions and the general model, are relevant for the design of closed-loop myoelectric prostheses utilizing tactile feedback

Multiscale modeling of circular and elliptical particles in laminar shear flow

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Detection and quantitation of HPV in genital and oral tissues and fluids by real time PCR

<p>Abstract</p> <p>Background</p> <p>Human papillomaviruses (HPVs) remain a serious world health problem due to their association with anogenital/oral cancers and warts. While over 100 HPV types have been identified, a subset is associated with malignancy. HPV16 and 18 are the most prevalent oncogenic types, while HPV6 and 11 are most commonly responsible for anogenital warts. While other quantitative PCR (qPCR) assays detect oncogenic HPV, there is no single tube assay distinguishing the most frequent oncogenic types and the most common types found in warts.</p> <p>Results</p> <p>A Sybr Green-based qPCR assay was developed utilizing degenerate primers to the highly conserved HPV E1 theoretically detecting any HPV type. A single tube multiplex qPCR assay was also developed using type-specific primer pairs and TaqMan probes that allowed for detection and quantitation of HPV6,11,16,18. Each HPV type was detected over a range from 2 × 10¹to 2 × 10⁶copies/reaction providing a reliable method of quantitating type-specific HPV in 140 anogenital/cutaneous/oral benign and malignant specimens. 35 oncogenic and low risk alpha genus HPV types were detected. Concordance was detected in previously typed specimens. Comparisons to the gold standard detected an overall sensitivity of 89% (95% CI: 77% - 96%) and specificity of 90% (95%CI: 52% - 98%).</p> <p>Conclusion</p> <p>There was good agreement between the ability of the qPCR assays described here to identify HPV types in malignancies previously typed using standard methods. These novel qPCR assays will allow rapid detection and quantitation of HPVs to assess their role in viral pathogenesis.</p

Prevalence, incidence, and clearance of human papillomavirus types covered by current vaccines in men with human immunodeficiency virus in the SUN Study

BACKGROUND: High-risk anal human papillomavirus (HPV) infection is prevalent among men living with human immunodeficiency virus (HIV); the association between 9-valent (9v) high-risk HPV (HR-HPV) vaccine types and abnormal cytology has not been well characterized. METHODS: We followed a prospective cohort study of persons with HIV at 7 HIV clinics in 4 US cities from March 2004 through June 2012. Annually, providers collected separate anal swabs for HPV detection and cytopathologic examination. Among men, we examined prevalence, incidence, and clearance of 9v HR-HPV vaccine types, compared with other HR types, and associations with abnormal cytology to assess potential vaccine impact. RESULTS: Baseline prevalence of any anal 9v HR-HPV type among men who have sex with men (MSM) and men who have sex with women (MSW) was 74% and 25% (P \u3c .001), respectively. Among 299 MSM, abnormal cytology was detected in 161 (54%) MSM and was associated with the presence of any 9v HR-HPV (relative risk [RR], 1.8 [95% confidence interval {CI}, 1.3-2.6]; P \u3c .001). Among 61 MSW, abnormal anal cytology was detected in 12 (20%) and was associated with the presence of any 9v HR-HPV (RR, 4.3 [95% CI, 1.6-11.5]; P \u3c .001). CONCLUSIONS: Among men with HIV, the prevalence of the 7 HR-HPV types in the 9v vaccine was high and was associated with abnormal cytology. These findings indicate that men with HIV could benefit from prophylactic administration of the 9v HPV vaccine

Detection and quantitation of HPV in anogenital and oral tissues and fluids of HIV-positive individuals by real-time PCR

Human papillomaviruses (HPV) remain a serious world health problem due to their association with anogenital and oral cancers and warts. While over 100 HPV types have been identified, only a subset is associated with malignancy. HPV16 and 18 are the most common oncogenic types, while HPV6 and 11 are the most common types responsible for anogenital warts. These four types cause up to 90% of HPV-associated disease. While other quantitative PCR (qPCR) assays can be used to detect oncogenic HPV, there is no single tube assay that distinguishes the most frequent oncogenic types and the most common types found in warts. A qPCR assay was developed that allowed for detection and quantitation of these 4 HPV types

Vitamin D deficiency is associated with IL-6 levels and monocyte activation in HIV-infected persons

Immune activation plays a key role in HIV pathogenesis. Markers of inflammation have been associated with vitamin D deficiency in the general population. Studies have also demonstrated associations of vitamin D deficiency with increased risk of HIV progression and death. The relationship between persistent inflammation and immune activation during chronic HIV infection and vitamin D deficiency remains unclear.Cryopreserved specimens were analyzed from 663 participants at the time of enrollment from the Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy (SUN Study) from 2004 to 2006. Biomarkers of inflammation, atherosclerosis, and coagulation were measured using enzyme-linked immunosorbent assays (ELISAs) and electrochemiluminescence. 25(OH)D, the stable precursor form of vitamin D, was measured using a radioimmunoassay with levels defined as: normal (≥30ng/mL), insufficient (20-29 ng/mL) and deficient (<20 ng/mL). Monocyte phenotypes were assessed by flow cytometry. Linear and logistic regression models were used to determine statistical associations between biomarkers and vitamin D deficiency.25(OH)D levels were deficient in 251 (38%) participants, insufficient in 222 (34%), and normal in 190 (29%). Patients with vitamin D deficiency, when compared to those with insufficient or normal vitamin D levels, had increased levels of IL-6 (23%; p<0.01), TNF-α (21%, p = 0.03), D-dimer (24%, p = 0.01), higher proportions of CD14dimCD16+ (22%, p<0.01) and CX3CR1+ monocytes (48%; p<0.001) and decreased frequency of CCR2+ monocytes (-3.4%, p<0.001). In fully adjusted models, vitamin D associations with abnormal biomarker levels persisted for IL-6 levels and CX3CR1+ and CCR2+ phenotypes.Vitamin D deficiency is associated with greater inflammation and activated monocyte phenotypes. The role of vitamin D deficiency in persistent immune activation and associated complications during chronic HIV disease should be further evaluated as a possible target for intervention

Selenotriapine – An isostere of the most studied thiosemicarbazone with pronounced pro-apoptotic activity, low toxicity and ability to challenge phenotype reprogramming of 3-D mammary adenocarcinoma tumors

Triapine, the most studied α-N-heterocyclic thiosemicarbazone, revealed potent activity against advanced leukemia, but was ineffective against a variety of solid tumors. Moreover, methemoglobinemia, which is a side effect of triapine administration, may limits all clinical application. To enhance anticancer activity and reduce side effects, we applied an isosteric replacement of sulfur to selenium atom was performed by synthesis and characterization of selenium triapine analog, 3-aminopyridine-2-carboxaldehyde selenosemicarbazone (selenotriapine). Compared to triapine, selenotriapine revealed superior pro-apoptotic activity with activation of intrinsic apoptotic pathway in both human monocytic leukemia (THP-1) and mammary adenocarcinoma (MCF-7) cell lines. For MCF-7 2-D cultures, selenotriapine induced notable increase in mitochondrial superoxide radical generation and dissipation of mitochondrial transmembrane potential. A significant delay in growth of MCF-7 spheroids (3-D culture) was accompanied by phenotypic stem cell reprogramming (Oct-4 expression). Additionally, selenotriapine demonstrated a very low toxicity profile as compared to triapine, confirmed over alleviated extent of methemoglobin formation and higher IC50 value in brine shrimp cytotoxicity assay

Prevalence, incidence, and clearance of anal high-risk human papillomavirus infection among HIV-infected men in the SUN study

BACKGROUND: The natural history of anal human papilloma virus (HPV) infection among human immunodeficiency virus (HIV)-infected men is unknown. METHODS: Annually, from 2004 to 2012, we examined baseline prevalence, incidence, and clearance of anal HPV infection at 48 months, and associated factors among HIV-infected men. RESULTS: We examined 403 men who have sex with men (MSM) and 96 men who have sex with women (MSW) (median age 42 years for both, 78% versus 81% prescribed cART, median CD4+ T-lymphocyte cell count 454 versus 379 cells/mm3, and 74% versus 75% had undetectable viral load, respectively). Type 16 prevalence among MSM and MSW was 38% versus 14% (P \u3c .001), and incidence 24% versus 7% (P = .001). Type 18 prevalence was 24% versus 8% (P \u3c .001), and incidence 13% versus 4% (P = .027). Among MSM and MSW, clearance of prevalent HPV 16 and HPV 18 was 31% and 60% (P = .392), and 47% and 25% (P = .297), respectively. Among MSM, receptive anal sex (with or without a condom) was associated with persistent HPV 16 (OR 2.24, P \u3c .001). CONCLUSIONS: MSM had higher prevalence and incidence of HPV than MSW, but similar clearance. Receptive anal sex may predict cancer risk among HIV-infected MSM