The impact of chronic untreated hyperglycaemia on the long-term stability of paraoxonase 1 (PON1) and antioxidant status in human sera

Semiconducting single wall carbon nanotubes (SWCNTs) fluoresce in the near infrared (NIR) and the emission wavelength depends on their chirality (n,m). Interactions with the environment affect the fluorescence and can be tailored by functionalizing SWCNTs with biopolymers such as DNA, which is the basis for fluorescent biosensors. So far, such biosensors were mainly assembled from mixtures of SWCNT chiralities with large spectral overlap, which affects sensitivity as well as selectivity and prevents multiplexed sensing. The main challenge to gain chirality pure sensors has been to combine approaches to isolate specific SWCNTs and generic (bio)functionalization approaches. Here, we created chirality pure SWCNT-based NIR biosensors for important analytes such as neurotransmitters and investigated the impact of SWCNT chirality/handedness as well as long-term stability and sensitivity. For this purpose, we used aqueous two-phase extraction (ATPE) to gain chirality pure (6,5)-, (7,5)-, (9,4)- and (7,6)- SWCNTs (emission at ~ 990, 1040, 1115 and 1130 nm). Exchange of the surfactant sodium deoxycholate (DOC) to specific singlestranded (ss)DNA sequences yielded monochiral sensors for small analytes (dopamine, riboflavin, ascorbic acid, pH). DOC used in the separation process was completely removed because residues impaired sensing. The assembled monochiral sensors were up to 10 times brighter than their non-purified counterparts and the ssDNA sequence affected absolute fluorescence intensity as well as colloidal (long-term) stability and selectivity for the analytes. (GT)40-(6,5)-SWCNTs displayed the maximum fluorescence response to the neurotransmitter dopamine (+140 %, Kd = 1.9 x10-7 M) and a long-term stability > 14 days. Furthermore, the specific ssDNA sequences imparted selectivity to the analytes independent of SWCNT chirality and handedness of (+/-) (6,5)-SWCNTs. These monochiral/single-color SWCNTs enabled ratiometric/multiplexed sensing of dopamine, riboflavin, H2O2 and pH. In summary, we demonstrated the assembly, characteristics and potential of monochiral (single-color) SWCNTs for multiple NIR fluorescent sensing applications.

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Sensing with Chirality Pure near Infrared Fluorescent Carbon Nanotubes

10.26434/chemrxiv.13005320.v1 ◽

2020 ◽

Author(s):

Robert Nißler ◽

Larissa Kurth, ◽

Han Li ◽

Alexander Spreinat ◽

Ilyas Kuhlemann ◽

...

Keyword(s):

Carbon Nanotubes ◽

Dna Sequences ◽

Near Infrared ◽

Single Wall Carbon Nanotubes ◽

Term Stability ◽

Long Term Stability ◽

Sensing Applications ◽

Main Challenge ◽

The Impact

Semiconducting single wall carbon nanotubes (SWCNTs) fluoresce in the near infrared (NIR) and the emission wavelength depends on their chirality (n,m). Interactions with the environment affect the fluorescence and can be tailored by functionalizing SWCNTs with biopolymers such as DNA, which is the basis for fluorescent biosensors. So far, such biosensors were mainly assembled from mixtures of SWCNT chiralities with large spectral overlap, which affects sensitivity as well as selectivity and prevents multiplexed sensing. The main challenge to gain chirality pure sensors has been to combine approaches to isolate specific SWCNTs and generic (bio)functionalization approaches. Here, we created chirality pure SWCNT-based NIR biosensors for important analytes such as neurotransmitters and investigated the impact of SWCNT chirality/handedness as well as long-term stability and sensitivity. For this purpose, we used aqueous two-phase extraction (ATPE) to gain chirality pure (6,5)-, (7,5)-, (9,4)- and (7,6)- SWCNTs (emission at ~ 990, 1040, 1115 and 1130 nm). Exchange of the surfactant sodium deoxycholate (DOC) to specific singlestranded (ss)DNA sequences yielded monochiral sensors for small analytes (dopamine, riboflavin, ascorbic acid, pH). DOC used in the separation process was completely removed because residues impaired sensing. The assembled monochiral sensors were up to 10 times brighter than their non-purified counterparts and the ssDNA sequence affected absolute fluorescence intensity as well as colloidal (long-term) stability and selectivity for the analytes. (GT)40-(6,5)-SWCNTs displayed the maximum fluorescence response to the neurotransmitter dopamine (+140 %, Kd = 1.9 x10-7 M) and a long-term stability > 14 days. Furthermore, the specific ssDNA sequences imparted selectivity to the analytes independent of SWCNT chirality and handedness of (+/-) (6,5)-SWCNTs. These monochiral/single-color SWCNTs enabled ratiometric/multiplexed sensing of dopamine, riboflavin, H2O2 and pH. In summary, we demonstrated the assembly, characteristics and potential of monochiral (single-color) SWCNTs for multiple NIR fluorescent sensing applications.

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Lip-to-incisor Relationship and Postorthodontic Long-term Stability of Cover-bite Treatment

The Angle Orthodontist ◽

10.2319/090205-309 ◽

2006 ◽

Vol 76 (6) ◽

pp. 942-949 ◽

Cited By ~ 14

Author(s):

Bernd G. Lapatki ◽

Dirk Baustert ◽

Jürgen Schulte-Mönting ◽

Sibylle Frucht ◽

Irmtrud E. Jonas

Keyword(s):

Central Incisor ◽

Lower Lip ◽

Maxillary Central Incisor ◽

Term Stability ◽

Long Term Stability ◽

Lateral Cephalograms ◽

Inducing Factors ◽

Line Level ◽

The Impact

Abstract Objective: To investigate the impact of a persisting high lip line and other potential relapse-inducing factors on long-term stability of orthodontic correction of retroinclined maxillary central incisors. Materials and Methods: Thirty-one cover-bite (“Deckbiss”) patients with retroinclined maxillary central incisors and a deep frontal overbite were evaluated. The maxillary central incisor inclination was determined odontometrically with study models made pretreatment, posttreatment, and at a follow-up examination (mean posttherapeutic interval: 9.0 years). The lip-to-incisor relationship, the interincisal angle, and the anteroposterior maxillary central incisor position were measured on lateral cephalograms taken after active treatment. Results: The relapse tendency of the orthodontic correction of the retroinclined maxillary central incisors displayed great interindividual variability with a range of posttherapeutic inclination change of −6.75° to +8.00°. Multiple regression analysis revealed an increased tendency for relapse in patients with (1) a high posttherapeutic (dorsal) lip line level combined with the maxillary central incisor and lower lip contact only in the incisal crown area (P < .01) and (2) a marked therapeutically induced inclination change of the maxillary central incisors (P < .05). Interrelations between the relapse of the corrected maxillary central incisors and other evaluated parameters were not statistically significant. Conclusions: For maximum treatment stability, the elimination of an excessive overlap of the upper incisors by the lower lip should be regarded as one of the most important therapeutic objectives when treating this malocclusion.

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Polymer anion-selective membrane for electrolytic water splitting: The impact of a liquid electrolyte composition on the process parameters and long-term stability

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2014.01.086 ◽

2014 ◽

Vol 39 (10) ◽

pp. 4779-4787 ◽

Cited By ~ 13

Author(s):

Jaromír Hnát ◽

Martin Paidar ◽

Jan Schauer ◽

Karel Bouzek

Keyword(s):

Water Splitting ◽

Process Parameters ◽

Liquid Electrolyte ◽

Electrolyte Composition ◽

Term Stability ◽

Long Term Stability ◽

Selective Membrane ◽

The Impact

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Transmission and Long-Term Stability of Compensated CD8 Escape Mutations

Journal of Virology ◽

10.1128/jvi.01108-08 ◽

2008 ◽

Vol 83 (8) ◽

pp. 3993-3997 ◽

Cited By ~ 47

Author(s):

Arne Schneidewind ◽

Zabrina L. Brumme ◽

Chanson J. Brumme ◽

Karen A. Power ◽

Laura L. Reyor ◽

...

Keyword(s):

Population Level ◽

Replication Capacity ◽

Compensatory Mutation ◽

Term Stability ◽

Long Term Stability ◽

Cell Responses ◽

Immunodeficiency Virus ◽

The Impact ◽

Restricted Epitope

ABSTRACT Human immunodeficiency virus effectively evades CD8+ T-cell responses through the development of CD8 escape mutations. Recent reports documenting reversion of transmitted mutations and the impact of specific escape mutations upon viral replication suggest that complex forces limit the accumulation of CD8 escape mutations at the population level. However, the presence of compensatory mutations capable of alleviating the impact of CD8 escape mutations on replication capacity may enable their persistence in an HLA-mismatched host. Herein, we illustrate the long-term stability of stereotypic escape mutations in the immunodominant HLA-B27-restricted epitope KK10 in p24/Gag following transmission when accompanied by a specific compensatory mutation.

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Systematic study on the impact of water on the performance and stability of perovskite solar cells

RSC Advances ◽

10.1039/c6ra11379f ◽

2016 ◽

Vol 6 (57) ◽

pp. 52448-52458 ◽

Cited By ~ 21

Author(s):

Charlotte Clegg ◽

Ian G. Hill

Keyword(s):

Solar Cells ◽

Systematic Study ◽

Perovskite Solar Cells ◽

Precursor Solution ◽

Term Stability ◽

Long Term Stability ◽

The Impact

Sequentially spin-coated inverted perovskite solar cells were constructed with systematically varied concentrations of water in the PbI2precursor solution. Surprisingly, small concentrations of water improved long-term stability, although with lower initial efficiency.

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