Mechanistic insight into the fluorescence activity of forensic fingerprinting reagents.

Fingerprint detection is still the primary investigative technique for deciphering criminal inquiries and identifying individuals. The main forensic fingerprinting reagents (FFRs) currently in use can require multiple treatment steps to produce fingerprints of sufficient quality. Therefore, the development of new, more effective FFRs that require minimal chemical treatment is of great interest in forensic chemistry. In this work, prudently crafted density functional theory and time-dependent density functional theory calculations are utilized to derive mechanistic insight into the optical activity of the non-fluorescent product of ninhydrin, diketohydrindylidenediketohydrindamine (DYDA), and fluorescent product of DFO (1,8-diazafluoren-9-one). We investigate various protonation sites to gain an understanding of isomeric preference in the solid-state material. A relaxed scan of a single torsion angle rotation in the S minimized geometry of the O-protonated DYDA isomer suggests a conical intersection upon ∼10° rotation. We show that the absence of a rigid hydrogen-bonded network in the crystal structure of DYDA supports the hypothesis of torsion rotation, which leads de-excitation to occur readily. Conversely, for the fluorescent DFO product, our calculations support an avoided crossing suggestive of a non-radiative mechanism when the torsion angle is rotated by about ∼100°. This mechanistic insight concurs with experimental observations of fluorescence activity in DFO and may aid the photophysical understanding of poorly visualized fingerprints due to weak fluorescence. We show that identifying suggestive avoided crossings via the method described here can be used to initialize thoughts toward the computational design of FFRs

A mathematical and computational review of Hartree-Fock SCF methods in Quantum Chemistry

We present here a review of the fundamental topics of Hartree-Fock theory in Quantum Chemistry. From the molecular Hamiltonian, using and discussing the Born-Oppenheimer approximation, we arrive to the Hartree and Hartree-Fock equations for the electronic problem. Special emphasis is placed in the most relevant mathematical aspects of the theoretical derivation of the final equations, as well as in the results regarding the existence and uniqueness of their solutions. All Hartree-Fock versions with different spin restrictions are systematically extracted from the general case, thus providing a unifying framework. Then, the discretization of the one-electron orbitals space is reviewed and the Roothaan-Hall formalism introduced. This leads to a exposition of the basic underlying concepts related to the construction and selection of Gaussian basis sets, focusing in algorithmic efficiency issues. Finally, we close the review with a section in which the most relevant modern developments (specially those related to the design of linear-scaling methods) are commented and linked to the issues discussed. The whole work is intentionally introductory and rather self-contained, so that it may be useful for non experts that aim to use quantum chemical methods in interdisciplinary applications. Moreover, much material that is found scattered in the literature has been put together here to facilitate comprehension and to serve as a handy reference.Comment: 64 pages, 3 figures, tMPH2e.cls style file, doublesp, mathbbol and subeqn package

Thyroid control over biomembranes: VI. Lipids in liver mitochondria and microsomes of hypothyroid rats

The lipids of liver mitochondria prepared from normal rats and from rats made hypothyroid by thyroidectomy and injection with131INa contained similar amounts, per mg protein, of total lipids, phospholipids, neutral lipids and lipid phosphorus. Hypothyroidism caused a doubling of the relative amounts of mitochondrial cardiolipins (CL; to 20.5% of the phospholipid P) and an accompanying trend (although statistically not significant) toward decreased amounts of both phosphatidylcholines (PC) and phosphatidylserines (PS), with phosphatidylethanolamines (PE) remaining unchanged. The pattern of elevated 18∶2 fatty acyl content and depleted 20∶4 acyl groups of the mitochondrial phospholipids of hypothyroid preparations was reflected to varying degrees in the resolved phospholipids, with PC showing greater degrees of abnormality than PE, and CL showing none. Hypothyroidism produced the same abnormal pattern of fatty acyl distributions in liver microsomal total lipids as was found in the mitochondria. Hypothyroid rats, when killed 6 hr after injection of [1‐14C] labeled linoleate, showed the following abnormalities: the liver incorporated less label into lipids, and converted 18∶2 not exclusively to 20∶4 (as normals do) but instead incorporated the label mainly into saturated fatty acids. These data, together with the known decrease in β‐oxidation, suggest that hypothyroidism involves possible defective step(s) in the conversion of 18∶2 to 20∶4.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142296/1/lipd0328.pd

Change in Blood Pressure Variability Among Treated Elderly Hypertensive Patients and Its Association With Mortality

Background: Information is scarce regarding effects of antihypertensive medication on blood pressure variability (BPV) and associated clinical outcomes. We examined whether antihypertensive treatment changes BPV over time and whether such change (decline or increase) has any association with long-term mortality in an elderly hypertensive population. Methods and Results: We used data from a subset of participants in the Second Australian National Blood Pressure study (n=496) aged ≥65 years who had 24-hour ambulatory blood pressure recordings at study entry (baseline) and then after a median of 2 years while on treatment (follow-up). Weighted day-night systolic BPV was calculated for both baseline and follow-up as a weighted mean of daytime and nighttime blood pressure standard deviations. The annual rate of change in BPV over time was calculated from these BPV estimates. Furthermore, we classified both BPV estimates as high and low based on the baseline median BPV value and then classified BPV changes into stable: low BPV, stable: high BPV, decline: high to low, and increase: low to high. We observed an annual decline (mean±SD: −0.37±1.95; 95% CI, −0.54 to −0.19; P<0.001) in weighted day-night systolic BPV between baseline and follow-up. Having constant stable: high BPV was associated with an increase in all-cause mortality (hazard ratio: 3.03; 95% CI, 1.67–5.52) and cardiovascular mortality (hazard ratio: 3.70; 95% CI, 1.62–8.47) in relation to the stable: low BPV group over a median 8.6 years after the follow-up ambulatory blood pressure monitoring. Similarly, higher risk was observed in the decline: high to low group. Conclusions: Our results demonstrate that in elderly hypertensive patients, average BPV declined over 2 years of follow-up after initiation of antihypertensive therapy, and having higher BPV (regardless of any change) was associated with increased long-term mortality

Excited-State Electronic Structure with Configuration Interaction Singles and Tamm–Dancoff Time-Dependent Density Functional Theory on Graphical Processing Units

Excited-state calculations are implemented in a development version of the GPU-based TeraChem software package using the configuration interaction singles (CIS) and adiabatic linear response Tamm–Dancoff time-dependent density functional theory (TDA-TDDFT) methods. The speedup of the CIS and TDDFT methods using GPU-based electron repulsion integrals and density functional quadrature integration allows full ab initio excited-state calculations on molecules of unprecedented size. CIS/6-31G and TD-BLYP/6-31G benchmark timings are presented for a range of systems, including four generations of oligothiophene dendrimers, photoactive yellow protein (PYP), and the PYP chromophore solvated with 900 quantum mechanical water molecules. The effects of double and single precision integration are discussed, and mixed precision GPU integration is shown to give extremely good numerical accuracy for both CIS and TDDFT excitation energies (excitation energies within 0.0005 eV of extended double precision CPU results)

Circulating microRNAs in sera correlate with soluble biomarkers of immune activation but do not predict mortality in ART treated individuals with HIV-1 infection: A case control study

Introduction: The use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals. Materials and Methods: A set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed. Results: None of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR- 145 correlated with nadir CD4+ T cell count. Discussion: No associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection

The NorthStar Ambulatory Assessment in Duchenne muscular dystrophy:Considerations for the design of clinical trials

Objective: With the emergence of experimental therapies for Duchenne muscular dystrophy (DMD), it is fundamental to understand the natural history of this disorder to properly design clinical trials. The aims of this study were to assess the effects produced on motor function by different DMD genotypes and early initiation of glucocorticoids. Methods: Through the NorthStar Network, standardised clinical data including the NorthStar Ambulatory Assessment score (NSAA) on 513 ambulant UK boys with DMD were analysed from 2004 to 2012. For the analysis of the genetic subpopulation, we also included data from 172 Italian boys with DMD. NSAA raw scores were converted into linear scores. Results: On the linearised NSAA, we observed an average decline of 8 units/year (4 units on raw NSAA analysis) after age 7. The median age at loss of ambulation (LOA) was 13 years (95% CI 12.1 to 13.5); 2 years prior to LOA, the estimated mean linearised NSAA score was 42/100 (13/34 raw scale). Starting glucocorticoids between 3 and 5 years conferred an additional gain in motor function of 3 units/year (1.3 raw units) up to age 7. When analysing the effect of genotype in the UK and Italian cumulative cohorts, individuals with deletions amenable to exons 44 and 46 skipping declined at a slower rate over 2 years (9 units (4 raw units), p<0.001), while 53 and 51 skippable deletions showed a faster decline of 14 (4.5; p<0.001) and 5 linearised units (2.4 NSAA units; p=0.02), respectively. Conclusions: Our study provides a novel insight on the current natural history of DMD, which will be instrumental for the design of future clinical trials

On the role of ethylene, auxin and a GOLVEN-like peptide hormone in the regulation of peach ripening

BACKGROUND: In melting flesh peaches, auxin is necessary for system-2 ethylene synthesis and a cross-talk between ethylene and auxin occurs during the ripening process. To elucidate this interaction at the transition from maturation to ripening and the accompanying switch from system-1 to system-2 ethylene biosynthesis, fruits of melting flesh and stony hard genotypes, the latter unable to produce system-2 ethylene because of insufficient amount of auxin at ripening, were treated with auxin, ethylene and with 1-methylcyclopropene (1-MCP), known to block ethylene receptors. The effects of the treatments on the different genotypes were monitored by hormone quantifications and transcription profiling. RESULTS: In melting flesh fruit, 1-MCP responses differed according to the ripening stage. Unexpectedly, 1-MCP induced genes also up-regulated by ripening, ethylene and auxin, as CTG134, similar to GOLVEN (GLV) peptides, and repressed genes also down-regulated by ripening, ethylene and auxin, as CTG85, a calcineurin B-like protein. The nature and transcriptional response of CTG134 led to discover a rise in free auxin in 1-MCP treated fruit. This increase was supported by the induced transcription of CTG475, an IAA-amino acid hydrolase. A melting flesh and a stony hard genotype, differing for their ability to synthetize auxin and ethylene amounts at ripening, were used to study the fine temporal regulation and auxin responsiveness of genes involved in the process. Transcriptional waves showed a tight interdependence between auxin and ethylene actions with the former possibly enhanced by the GLV CTG134. The expression of genes involved in the regulation of ripening, among which are several transcription factors, was similar in the two genotypes or could be rescued by auxin application in the stony hard. Only GLV CTG134 expression could not be rescued by exogenous auxin. CONCLUSIONS: 1-MCP treatment of peach fruit is ineffective in delaying ripening because it stimulates an increase in free auxin. As a consequence, a burst in ethylene production speeding up ripening occurs. Based on a network of gene transcriptional regulations, a model in which appropriate level of CTG134 peptide hormone might be necessary to allow the correct balance between auxin and ethylene for peach ripening to occur is proposed. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12870-016-0730-7) contains supplementary material, which is available to authorized users