Detection of foodborne pathogens in contaminated food using nanomaterial-based electrochemical biosensors.

Foodborne pathogens are a grave concern for the for food, medical, environmental, and economic sectors. Their ease of transmission and resistance to treatments, such as antimicrobial agents, make them an important challenge. Food tainted with these pathogens is swiftly rejected, and if ingested, can result in severe illnesses and even fatalities. This review provides and overview of the current status of various pathogens and their metabolites transmitted through food. Despite a plethora of studies on treatments to eradicate and inhibit these pathogens, their indiscriminate use can compromise the sensory properties of food and lead to contamination. Therefore, the study of detection methods such as electrochemical biosensors has been proposed, which are devices with advantages such as simplicity, fast response, and sensitivity. However, these biosensors may also present some limitations. In this regard, it has been reported that nanomaterials with high conductivity, surface-to-volume ratio, and robustness have been observed to improve the detection of foodborne pathogens or their metabolites. Therefore, in this work, we analyze the detection of pathogens transmitted through food and their metabolites using electrochemical biosensors based on nanomaterials.

Polluted water from a storage dam (Villa Victoria, méxico) induces oxidative damage, AChE activity, embryotoxicity, and behavioral changes in Cyprinus carpio larvae.

The Villa Victoria dam is one of the most important storage reservoirs in Mexico since it distributes water to more than 20 million inhabitants in the Metropolitan Zone of Mexico City. In this dam, the common carp (Cyprinus carpio) is an important food resource for the inhabitants, so the aim of this work was to evaluate the oxidative damage (lipoperoxidation, oxidized proteins, antioxidant enzymes activity and gene expression), AChE, embryotoxicity and behavioral changes in C. carpio embryos and larvae exposed to water from Villa Victoria dam for 24, 48, 72 and 96 h. The embryotoxicity was evaluated trough the General Morphology Score (GMS) and the teratogenic index. Behavioral changes in basal locomotor activity and thigmotaxis were evaluated in a DanioVision, Noldus ™. An increase in lipid and protein oxidation as well as modification of CAT, SOD and GPx enzymatic activity was observed during the exposure times. The GMS indicated a low development in the embryos, the teratogenic index was less than 1, however teratogenic effects as yolk edema, fin malformation, head malformation and scoliosis were observed. In parallel, an increase in AChE activity and gene expression was observed reflecting changes in distance traveled of the basal locomotor activity and thigmotaxis at the sampling points. In conclusion, pollutants in water from Villa Victoria dam caused oxidative damage, changes in SOD, CAT, GPx and AChE activity as well as embryotoxicity and modifications in the behavior of C. carpio larvae. This study demonstrates the need to implement restoration programs for this reservoir since, contamination in the Villa Victoria dam could eventually endanger aquatic life and human health.

Biosynthesis of Polyhydroalkanoates Doped with Silver Nanoparticles Using Pseudomonas putida and Pseudomonas aeruginosa for Antibacterial Polymer Applications.

In this study, the biosynthesis of polyhydroxyalkanoates (PHAs) was carried out using Pseudomonas putida and Pseudomonas aeruginosa. These PHAs were produced using reagent-grade glycerol and crude glycerol as the carbon sources. The objective was to compare the production of PHAs and to functionalize these polymers with silver nanoparticles to provide antibacterial properties for potential biomedical applications. The findings from the physical and chemical analyses confirmed the successful synthesis and extraction of PHAs, achieving comparable yields using both crude glycerol and reagent-grade glycerol as carbon sources across both strains. Approximately 16% higher PHAs production was obtained using Pseudomonas putida compared to Pseudomonas aeruginosa, and no significant difference was observed in the production rate of PHAs between the two carbon sources used, which means that crude glycerol could be utilized even though it has more impurities. Notably, PHAs functionalized with silver nanoparticles showed improved antibacterial effectiveness, especially those derived from reagent-grade glycerol and the Pseudomonas aeruginosa strain.

Identification of Dp140 and α1-syntrophin as novel molecular interactors of the neuronal CaV2.1 channel.

The primary function of dystrophin is to form a link between the cytoskeleton and the extracellular matrix. In addition to this crucial structural function, dystrophin also plays an essential role in clustering and organizing several signaling proteins, including ion channels. Proteomic analysis of the whole rodent brain has stressed the role of some components of the dystrophin-associated glycoprotein complex (DGC) as potential interacting proteins of the voltage-gated Ca2+ channels of the CaV2 subfamily. The interaction of CaV2 with signaling and scaffolding proteins, such as the DGC components, may influence their function, stability, and location in neurons. This work aims to study the interaction between dystrophin and CaV2.1. Our immunoprecipitation data showed the presence of a complex formed by CaV2.1, CaVα2δ-1, CaVß4e, Dp140, and α1-syntrophin in the brain. Furthermore, proximity ligation assays (PLA) showed that CaV2.1 and CaVα2δ-1 interact with dystrophin in the hippocampus and cerebellum. Notably, Dp140 and α1-syntrophin increase CaV2.1 protein stability, half-life, permanence in the plasma membrane, and current density through recombinant CaV2.1 channels. Therefore, we have identified the Dp140 and α1-syntrophin as novel interaction partners of CaV2.1 channels in the mammalian brain. Consistent with previous findings, our work provides evidence of the role of DGC in anchoring and clustering CaV channels in a macromolecular complex.

Blood donor notification rate in a blood bank in Veracruz, Mexico.

Blood banks are primarily responsible for providing safe blood, but they also indirectly act to prevent the spread of infectious diseases by notifying blood donors of positive screening results. The notification process differs between countries and notifications rates are generally low. This study sought to analyze the notification rate of healthy and infection-positive donors who donated blood at CETS-Veracruz. A total of 41790 donors were analyzed, 1585 (3.79%) were positive for one or more of the screened infection markers. Only 4163 (9.96% of the total) were notified about their serology results. Of the positive donors, 157 were contacted by phone call; of them, 91 (57%) returned to the blood bank for their results. The average notification rate for positive donors was only 17.48%. The highest notification rate was for anti-HBc (26.63%), while the lowest was for HBsAg (4.17%). Age significantly influenced the return of donors: Those aged 18-24 and 25-39 years were 4.71 and 1.64 times less likely, respectively, to return for their results compared to the rate for all ages. The advice received in the pre-donation stage about the risks of transfusion-transmitted infections and the relevance of returning for results did not appear to impact donors, since the rate of notification was lower than those reported internationally. These data indicate that CETS-Veracruz should improve donor data registration and communication mechanisms to increase the notification rate, and that donor notification studies should be carried out in other Mexican blood banks to analyze the return rate at the national level.

Direct Fabrication of a Copper RTD over a Ceramic-Coated Stainless-Steel Tube by Combination of Magnetron Sputtering and Sol-Gel Techniques.

Reducing the economic and environmental impact of industrial process may be achieved by the smartisation of different components. In this work, tube smartisation is presented via direct fabrication of a copper (Cu)-based resistive temperature detector (RTD) on their outer surfaces. The testing was carried out between room temperature and 250 °C. For this purpose, copper depositions were studied using mid-frequency (MF) and high-power impulse magnetron sputtering (HiPIMS). Stainless steel tubes with an outside inert ceramic coating were used after giving them a shot blasting treatment. The Cu deposition was performed at around 425 °C to improve adhesion as well as the electrical properties of the sensor. To generate the pattern of the Cu RTD, a photolithography process was carried out. The RTD was then protected from external degradation by a silicon oxide film deposited over it by means of two different techniques: sol-gel dipping technique and reactive magnetron sputtering. For the electrical characterisation of the sensor, an ad hoc test bench was used, based on the internal heating and the external temperature measurement with a thermographic camera. The results confirm the linearity (R2 > 0.999) and repeatability in the electrical properties of the copper RTD (confidence interval < 0.0005).

Experimental and Theoretical Studies on Acid Corrosion Inhibition of API 5L X70 Steel with Novel 1-N-α-d-Glucopyranosyl-1H-1,2,3-Triazole Xanthines.

A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules.

Ion channel long non-coding RNAs in neuropathic pain.

Neuropathic pain is one of the primary forms of chronic pain and is the consequence of the somatosensory system's direct injury or disease. It is a relevant public health problem that affects about 10% of the world's general population. In neuropathic pain, alteration in neurotransmission occurs at various levels, including the dorsal root ganglia, the spinal cord, and the brain, resulting from the malfunction of diverse molecules such as receptors, ion channels, and elements of specific intracellular signaling pathways. In this context, there have been exciting advances in elucidating neuropathic pain's cellular and molecular mechanisms in the last decade, including the possible role that long non-coding RNAs (lncRNAs) may play, which open up new alternatives for the development of diagnostic and therapeutic strategies for this condition. This review focuses on recent studies associated with the possible relevance of lncRNAs in the development and maintenance of neuropathic pain through their actions on the functional expression of ion channels. Recognizing the changes in the function and spatio-temporal patterns of expression of these membrane proteins is crucial to understanding the control of neuronal excitability in chronic pain syndromes.

Cooperative synaptic and intrinsic plasticity in a disynaptic limbic circuit drive stress-induced anhedonia and passive coping in mice.

Stress promotes negative affective states, which include anhedonia and passive coping. While these features are in part mediated by neuroadaptations in brain reward circuitry, a comprehensive framework of how stress-induced negative affect may be encoded within key nodes of this circuit is lacking. Here, we show in a mouse model for stress-induced anhedonia and passive coping that these phenomena are associated with increased synaptic strength of ventral hippocampus (VH) excitatory synapses onto D1 medium spiny neurons (D1-MSNs) in the nucleus accumbens medial shell (NAcmSh), and with lateral hypothalamus (LH)-projecting D1-MSN hyperexcitability mediated by decreased inwardly rectifying potassium channel (IRK) function. Stress-induced negative affective states are prevented by depotentiation of VH to NAcmSh synapses, restoring Kir2.1 function in D1R-MSNs, or disrupting co-participation of these synaptic and intrinsic adaptations in D1-MSNs. In conclusion, our data provide strong evidence for a disynaptic pathway controlling maladaptive emotional behavior.

The avocado genome informs deep angiosperm phylogeny, highlights introgressive hybridization, and reveals pathogen-influenced gene space adaptation.

The avocado, Persea americana, is a fruit crop of immense importance to Mexican agriculture with an increasing demand worldwide. Avocado lies in the anciently diverged magnoliid clade of angiosperms, which has a controversial phylogenetic position relative to eudicots and monocots. We sequenced the nuclear genomes of the Mexican avocado race, P. americana var. drymifolia, and the most commercially popular hybrid cultivar, Hass, and anchored the latter to chromosomes using a genetic map. Resequencing of Guatemalan and West Indian varieties revealed that ∼39% of the Hass genome represents Guatemalan source regions introgressed into a Mexican race background. Some introgressed blocks are extremely large, consistent with the recent origin of the cultivar. The avocado lineage experienced 2 lineage-specific polyploidy events during its evolutionary history. Although gene-tree/species-tree phylogenomic results are inconclusive, syntenic ortholog distances to other species place avocado as sister to the enormous monocot and eudicot lineages combined. Duplicate genes descending from polyploidy augmented the transcription factor diversity of avocado, while tandem duplicates enhanced the secondary metabolism of the species. Phenylpropanoid biosynthesis, known to be elicited by Colletotrichum (anthracnose) pathogen infection in avocado, is one enriched function among tandems. Furthermore, transcriptome data show that tandem duplicates are significantly up- and down-regulated in response to anthracnose infection, whereas polyploid duplicates are not, supporting the general view that collections of tandem duplicates contribute evolutionarily recent "tuning knobs" in the genome adaptive landscapes of given species.

The role of voltage-gated calcium channels in the pathogenesis of Parkinson's disease.

Aim: Voltage-gated calcium (CaV) channels play an essential role in maintaining calcium homeostasis and regulating numerous physiological processes in neurons. Therefore, dysregulation of calcium signaling is relevant in many neurological disorders, including Parkinson's disease (PD). This review aims to introduce the role of CaV channels in PD and discuss some novel aspects of channel regulation and its impact on the molecular pathophysiology of the disease.Methods: an exhaustive search of the literature in the field was carried out using the PubMed database of The National Center for Biotechnology Information. Systematic searches were performed from the initial date of publication to May 2022.Results: Although α-synuclein aggregates are the main feature of PD, L-type calcium (CaV1) channels seem to play an essential role in the pathogenesis of PD. Changes in the functional expression of CaV1.3 channels alter Calcium homeostasis and contribute to the degeneration of dopaminergic neurons. Furthermore, recent studies suggest that CaV channel trafficking towards the cell membrane depends on the activity of the ubiquitin-proteasome system (UPS). In PD, there is an increase in the expression of L-type channels associated with a decrease in the expression of Parkin, an E3 enzyme of the UPS. Therefore, a link between Parkin and CaV channels could play a fundamental role in the pathogenesis of PD and, as such, could be a potentially attractive target for therapeutic intervention.Conclusion: The study of alterations in the functional expression of CaV channels will provide a framework to understand better the neurodegenerative processes that occur in PD and a possible path toward identifying new therapeutic targets to treat this condition.

A model for the regulation of apoptosis intrinsic pathway: The potential role of the transcriptional regulator E2F in the point of no return.

Apoptosis has been extensively characterized by both experimental approaches and model simulations. However, it is still not fully understood how the regulation occurs, especially in the intrinsic pathway, which can be activated by a great variety of signals. In addition, the conditions in which a point of no return could be reached remain elusive. In this work, we use differential equations models to approach these issues. Our starting point was the model for caspase activation of Legewie et al. (Legewie S, et al., PLoS Computational Biology 2006, 2(9): e120), which exhibits irreversible bistability. We added an activation module to this model, with the main events related to mitochondrial outer membrane permeabilization, which includes cytochrome C release by the mitochondria and its effects on caspase activation and respiratory chain disruption. This "Extended Legewie Model" (ELM) uses BAK as the apoptotic stimulus and active caspase 3 as a measure of apoptosis activation. Unexpectedly, in the extended model, BAK cannot trigger apoptosis activation using physiologically sound initial values of the variables, due to limitations in apoptosome concentration increase. Therefore, the next step was to find a regulatory mechanism, allowing apoptosis activation in the ELM, starting from physiological initial concentrations. For this aim, we performed a sensitivity analysis on the 61 parameters of the system, finding that those producing the most relevant changes in the qualitative behaviour were the rates of synthesis of caspase 3, caspase 9 and XIAP. Based on these results, the transcription factor E2F was included in the ELM because it directly regulates the rate of synthesis of caspase 3 and 9. Depending on the concentration of E2F, the ELM shows different qualitative behaviours. On one hand, for low E2F apoptosis is impossible and for high E2F apoptosis is inevitable. Therefore, if E2F is sufficiently increased, the point of no return is crossed. On the other hand, for intermediate values of E2F there is a bistable region where the fate of the system also depends on the concentration of BAK and other signalling species.

Efficacy and safety of switching Jak inhibitors in rheumatoid arthritis: an observational study.

OBJECTIVES: Different Jak inhibitors (jakinibs) have shown efficacy in rheumatoid arthritis (RA), but in a significant proportion of patients, an insufficient response leads to therapy withdrawal. We describe the efficacy and safety of a second jakinib in patients stopping the first due to insufficient response or side effects. METHODS: This is an observational retrospective multicentric study of 31 patients with RA sequentially treated with baricitinib or tofacitinib in any order in clinical practice in ten medical centres in Spain. RESULTS: We identified 31 patients, sequentially treated with both jakinibs. An equal proportion had received tofacitinib or baricitinib first. Most patients (87%) had previously received one or several bDMARD, median 4 (2-5). Median survival for the first jakinib was 5 (3-8) months, and the reasons for withdrawal were inefficacy in 61% and adverse effects in 39%. Most patients (23/31, 74%) maintained the response to the second jakinib after a mean follow-up of 19.5 (12-24) months. In all 8 patients who discontinued the second jakinib, the reason was inefficacy. The treatment suspension rate was similar among patients that had discontinued the first jakinib for inefficacy (26%) or for adverse effects (25%). CONCLUSIONS: Therapy of RA with a second jakinib seems a safe and efficacious option after discontinuation of the first, either for inefficacy or for side effects.

Healthcare is a Team Sport: Stress, Resilience, and Correlates of Well-Being Among Health System Employees in a Crisis.

EXECUTIVE SUMMARY: While the COVID-19 pandemic has added stressors to the lives of healthcare workers, it is unclear which factors represent the most useful targets for interventions to mitigate employee distress across the entire healthcare team. A survey was distributed to employees of a large healthcare system in the Southeastern United States, and 1,130 respondents participated. The survey measured overall distress using the 9-item Well-Being Index (WBI), work-related factors, moral distress, resilience, and organizational-level factors. Respondents were also asked to identify major work, clinical, and nonwork stressors. Multivariate regression was used to evaluate associations between employee characteristics and WBI distress score. Overall, 82% of employees reported high distress (WBI ≥ 2), with nurses, clinical support staff, and advanced practice providers reporting the highest average scores. Factors associated with higher distress included increased job demands or responsibilities, heavy workload or long hours, higher frequency of moral distress, and loneliness or social isolation. Factors associated with lower distress were perceived organizational support, work control, perceived fairness of salary cuts, and resilience. Most factors significantly associated with distress-heavy workloads and long hours, increased job demands, and moral distress, in particular-were work-related, indicating that efforts can be made to mitigate them. Resilience explained a small portion of the variance in distress relative to other work-related factors. Ensuring appropriate staffing levels may represent the single largest opportunity to significantly move the needle on distress. However, the financial impact of the COVID-19 pandemic on the healthcare system may represent a barrier to addressing these stressors.

Complete blood count differences in a cohort of Down syndrome neonates with transient abnormal myelopoiesis screened for GATA1 pathogenic variants.

Transient abnormal myelopoiesis (TAM) raises the risk for acute myeloid leukemia of Down syndrome (DS) (ML-DS), and both are related to GATA1 pathogenic variants. Here, we analyzed which findings on complete blood count (CBC) are associated with TAM in a cohort of neonates with DS screened for GATA1 pathogenic variants. The CBCs were compared among 70 newborns with DS, including 16 patients (22.9%) with TAM (cases), and 54 patients (77.1%) without TAM (controls). TAM was defined as peripheral circulating blasts (PCBs) ≥ 1%. PCR and direct sequencing were used to screen DNA samples from peripheral blood for GATA1 exon 2 mutations. Multivariate logistic regression analyses determined that the mean count of lymphocytes was significantly higher in DS infants with TAM (p = .035) and that lymphocytosis confers a risk for TAM (adjusted odds ratio = 7.23, 95% confidence intervals: 2.02-25.92). Pathogenic variants of GATA1 were identified in 2 of 70 analyzed DS neonates (2.9%), of which one had ML-DS and another had an asymptomatic TAM. Among those DS infants with TAM, the GATA1 pathogenic variant detection was 12.5%. Our results indicated that lymphocytosis is associated with TAM in neonates with DS. However, since not all infants with an abnormal CBC had TAM, and not all infants with TAM had GATA1 pathogenic variants, we emphasize that only the search for GATA1 pathogenic variants allows the proper identification of the subgroup of DS infants with a real increasing in risk for ML-DS.

Practices and Barriers in Sexual History Taking: A Cross-Sectional Study in a Public Adult Primary Care Clinic.

BACKGROUND: Surveys report low frequencies of sexual history (SH) obtained in primary care. Sexually transmitted infections incidence can be reduced with timely screening. It is important to determine whether providers obtain thorough SH and to identify needs for improvement. AIM: To evaluate the frequency and depth of SH taking in primary care. METHODS: In this cross-sectional cohort study, 1,017 primary care visits were reviewed (1,017 adult patients, female 55.26%). 417 patients were seen by male providers and 600 patients were seen by female providers. Multivariate ordered and logit models were deployed. MAIN OUTCOME MEASURES: The primary outcome measures included SH taking rates and completeness based on the 5 P model as described by the Centers for Disease Control and Prevention. RESULTS: All components of SH were explored in 1.08% of visits. Partial SH was obtained in 33.92% of visits. No SH was taken in the majority of visits (65%). SH was more likely to be taken from female patients than from male patients (P < .001), and was less likely to be obtained from older patients as compared to younger individuals (P < .001). There was no significant difference in SH taking between male and female providers (P = .753). The provider title and the level of training were found to be independent predictors of SH taking (P < .001). CLINICAL IMPLICATIONS: The results of this study highlight an unmet need for more comprehensive and consistent SH taking amongst providers, particularly in high-risk settings, so that SH can be used as a valuable tool in preventive care. STRENGTHS & LIMITATIONS: To the best of our knowledge, this is the largest study to date examining SH taking in the primary care setting. Limitations include the retrospective study design, lack of generalizability to other hospitals, and inconsistencies in available data. CONCLUSION: The SH taking rates in primary care clinics are globally low with a variation depending on the provider position or level of training, provider gender, and patient age. Palaiodimos L, Herman HS, Wood E, et al. Practices and Barriers in Sexual History Taking: A Cross-Sectional Study in a Public Adult Primary Care Clinic. J Sex Med 2020;17:1509-1519.

Subcutaneous Tocilizumab in Monotherapy or in Combination With Nonbiologic Disease-Modifying Antirheumatic Drugs in Latin American Patients With Moderate to Severe Active Rheumatoid Arthritis: A Multicenter, Phase IIIb Study.

OBJECTIVE: To assess the efficacy and safety of subcutaneous tocilizumab (TCZ) in combination with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) in Latin American patients with rheumatoid arthritis (RA) and inadequate response to previous csDMARDs. METHODS: ML28700 was a multicenter, open-label, single-arm trial. Previously treated RA patients who had not received treatment with TCZ or any biological agent (n = 284) and with a baseline Disease Activity Score in 28 joints based on erythrocyte sedimentation rate (DAS28-ESR) of 3.2 or greater were assigned to receive subcutaneous TCZ (162 mg/wk) in association with csDMARD for 24 weeks. Patients who achieved remission (DAS28-ESR <2.6) at week 24 continued with TCZ as monotherapy until week 52; otherwise, they continued with their assigned treatment. The primary efficacy end point was remission rate (DAS28-ESR <2.6) at weeks 24 and 52. Secondary objectives included disease activity scores, safety, and quality of life. RESULTS: At week 24, a total of 169 patients (59.5%; 95% confidence interval, 53.5%-65.3%) achieved remission, 91 patients (32.0%) had low disease activity, and 46 patients (8.4%) were not responders. Sustained remission at week 52 was achieved by 80.8% (n = 126) of patients who continued with TCZ monotherapy versus 44.6% (n = 37) of those on combination therapy. A total of 241 patients (84.9%; 95% confidence interval, 80.2%-88.8%) had at least 1 adverse event during follow-up. Adverse events led to drug modification in 32 patients (11.3%) or discontinuation in 21 patients (7.4%). CONCLUSIONS: Subcutaneous TCZ is an efficacious therapy with long-lasting results and tolerable adverse events in Latin American patients with RA.Trial registration no.: NCT02011334 Tozura Study Program.

Composites of Anthraquinone Dyes@HKUST-1 with Tunable Microstructuring: Experimental and Theoretical Interaction Studies.

The metal-organic framework (MOF) HKUST-1 was employed as an interaction matrix for fundamental loading studies of anthraquinone dyes. Chosen dyes were alizarin (A), alizarin S (AS), disperse blue 1 (B1), disperse blue 3 (B3), disperse blue 56 (B56) and purpurin (P). All materials were characterized by XRD, FTIR, TGA and SEM. Hence the interaction of dyes with the framework was characterized by theoretical-experimental differential analysis. One-pot loading strategy resulted in more efficient scavenging of dyes, and reached 100 % for B56 using 50 mg L-1 . SEM revealed important microstructural changes, the smaller crystals ranged 0.8-3 µm in size and almost all composite sizes were from this to higher values, reaching 70 µm, with varying shapes. Two composites were larger in size range (about 2500-1000 µm), and were shaped as rods, octahedrons and coffin lids. Indeed, the microstructure could be modulated depending on preparation conditions and type of loaded dye. For the higher loading series, N2 adsorption and XPS experiments were carried on to further evidence dye-MOF interactions. Ab initio prediction of structural properties for A@HKUST-1 and P@HKUST-1 were obtained by means of solid-state CRYSTAL14 code at the PBE0 level of theory. Computed findings evidenced two O→Cu coordinative bonds, one from O-ketone and the other from O-phenolate moiety as main interactions towards CuNET centers.

Diversity of yeast species from Dutch garden soil and the description of six novel Ascomycetes.

A Citizen Science initiative by the Westerdijk Fungal Biodiversity Institute and the Utrecht University Museum gave rise to a project where fungal and yeast isolates were obtained and identified from Dutch soil samples. During the current study, 386 yeast strains were isolated from 157 different locations in the Netherlands. These strains were identified using sequence data of the large-subunit rRNA gene (D1/D2 region) and the internal transcribed spacer 1 and 2 regions. A total of 53 different yeast species were found as well as 15 potentially novel species. Six novel ascomycetous species are described during this study that include Hanseniaspora mollemarum sp. nov., Ogataea degrootiae sp. nov., Pichia gijzeniarum sp. nov., Saccharomycopsis oosterbeekiorum sp. nov., Trichomonascus vanleenenius sp. nov. and Zygoascus flipseniorum sp. nov. This study made it possible to incorporate numerous yeast isolates into the CBS collection without any restrictions, which make these isolates readily available for use by others. Many of the isolates represented species of which only a few isolates or even only a single ex-type strain were available. Therefore, it is a clear indication that such biodiversity-orientated Citizen Science projects can enrich the pool of available yeasts for future research projects.

Low-Spin Fe(III) Macrocyclic Complexes of Imidazole-Appended 1,4,7-Triazacyclononane as Paramagnetic Probes.

Two macrocyclic complexes of 1,4,7-triazacyclononane (TACN), one with N-methyl imidazole pendants, [Fe(Mim)]3+, and one with unsubstituted NH imidazole pendants, [Fe(Tim)]3+, were prepared with a view toward biomedical imaging applications. These low-spin Fe3+ complexes produce moderately paramagnetically shifted and relatively sharp 1H NMR resonances for paraSHIFT and paraCEST applications. The [Fe(Tim)]3+ complex undergoes pH-dependent changes in NMR spectra in solution that are consistent with the consecutive deprotonation of all three imidazole pendant groups at high pH values. N-Methylation of the imidazole pendants in [Fe(Mim)]3+ produces a complex that dissociates more readily at high pH in comparison to [Fe(Tim)]3+, which contains ionizable donor groups. Cyclic voltammetry studies show that the redox potential of [Fe(Mim)]3+ is invariant with pH ( E1/2 = 328 ± 3 mV vs NHE) between pH 3.2 and 8.4, unlike the Fe(III) complex of Tim which shows a 590 mV change in redox potential over the pH range of 3.3-12.8. Magnetic susceptibility studies in solution give magnetic moments of 0.91-1.3 cm3 K mol-1 (µeff value = 2.7-3.2) for both complexes. Solid-state measurements show that the susceptibility is consistent with a S = 1/2 state over the temperature range of 0 to 300 K, with no crossover to a high-spin state under these conditions. The crystal structure of [Fe(Mim)](OTf)3 shows a six-coordinate all-nitrogen bound Fe(III) in a distorted octahedral environment. Relativistic ab initio wave function and density functional theory (DFT) calculations on [Fe(Mim)]3+, some with spin orbit coupling, were used to predict the ground spin state. Relative energies of the doublet, quartet, and sextet spin states were consistent with the doublet S = 1/2 state being the lowest in energy and suggested that excited states with higher spin multiplicities are not thermally accessible. Calculations were consistent with the magnetic susceptibility determined in the solid state.