Missed Opportunities for HIV Prevention in a Large County Safety Net Health System.

INTRODUCTION: HIV pre-exposure prophylaxis (PrEP) is effective at reducing HIV transmission. However, PrEP uptake is low for racial and ethnic minorities and women, especially in the Southern US Health care clinicians should be prepared to identify all patients eligible for PrEP, provide counseling, and prescribe PrEP. METHODS: Retrospective analysis of persons newly diagnosed with HIV was conducted at a large public health system from January 2015 to June 2021. Interactions with the health system in the 5 years preceding HIV diagnosis were analyzed, and missed opportunities for HIV prevention interventions, including PrEP and condom use counseling, were identified. RESULTS: We identified 454 patients with a new HIV diagnosis with previous health system interactions. 166(36.6%) had at least 1 identifiable indication for PrEP: 42(9.3%) bacterial STI, 63(13.9%) inconsistent condom use, or 82(18%) injection drug use before HIV diagnosis. Only 7(1.5%) of patients were counseled on PrEP. Most patients (308; 67.8%) had no documented condom use history in the EHR before diagnosis, a surrogate marker for obtaining a sexual history. Patients who exclusively interacted with the emergency care setting did not receive PrEP education and were less likely to receive condom use counseling. CONCLUSION: Missed opportunities to offer HIV prevention before diagnosis were common among patients newly diagnosed with HIV. Most patients did not have sexual history documented in the chart before their HIV diagnosis. Educational interventions are needed to ensure that clinicians are prepared to identify those eligible and discuss the benefits of PrEP.

Enhanced Nesquehonite Formation and Stability in the Presence of Dissolved Silica.

One possible carbon dioxide sequestration strategy is via the carbonation of dissolved Mg2+ obtained through olivine ((Mg,Fe)2SiO4) dissolution. However, silica is also produced during the breakdown of olivine. This component may have a detrimental effect on the yield of Mg-carbonate as Mg2+ incorporation into complex Mg silicate phases would limit CO2 uptake by this system. Yet this potential competition is currently not considered. Here, we use crystal growth experiments at temperatures applicable for potential coastal applications to test the effect of silica on the formation of the hydrated Mg-carbonate phase nesquehonite (MgCO3·3H2O). Solution chemistry analysis coupled with phase identification demonstrates that the presence of silica in the solution can actually assist the formation of nesquehonite and increase its yield by as much as 60 times. Our findings suggest that the presence of silica changes interfacial stabilities, lowering the energetic barrier for nesquehonite nucleation. In addition, in situ attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) transformation experiments demonstrated that nesquehonite precipitating in a solution containing a high concentration of dissolved silica exhibits enhanced stability against its transformation into hydromagnesite. These findings will help to better constrain what we expect for applications of olivine during carbon remediation strategies as well as assist yields for industrial applications that use Mg-based cement as building materials to facilitate a CO2-neutral or negative footprint.

A post-transcriptional regulatory landscape of aging in the female mouse hippocampus.

Aging is associated with substantial physiological changes and constitutes a major risk factor for neurological disorders including dementia. Alterations in gene expression upon aging have been extensively studied; however, an in-depth characterization of post-transcriptional regulatory events remains elusive. Here, we profiled the age-related changes of the transcriptome and translatome in the female mouse hippocampus by RNA sequencing of total RNA and polysome preparations at four ages (3-, 6-, 12-, 20-month-old); and we implemented a variety of bioinformatics approaches to unravel alterations in transcript abundance, alternative splicing, and polyadenylation site selection. We observed mostly well-coordinated transcriptome and translatome expression signatures across age including upregulation of transcripts related to immune system processes and neuroinflammation, though transcripts encoding ribonucleoproteins or associated with mitochondrial functions, calcium signaling and the cell-cycle displayed substantial discordant profiles, suggesting translational control associated with age-related deficits in hippocampal-dependent behavior. By contrast, alternative splicing was less preserved, increased with age and was associated with distinct functionally-related transcripts encoding proteins acting at synapses/dendrites, RNA-binding proteins; thereby predicting regulatory roles for RBM3 and CIRBP. Only minor changes in polyadenylation site selection were identified, indicating pivotal 3'-end selection in young adults compared to older groups. Overall, our study provides a comprehensive resource of age-associated post-transcriptional regulatory events in the mouse hippocampus, enabling further examination of the molecular features underlying age-associated neurological diseases.

Implementation of Sexual Health Curriculum Series: Educational Initiative to Increase STI Screening and Treatment in Dallas, Texas.

OBJECTIVE: A new monthly virtual education curriculum on sexual healthcare was launched in 2021. This is an analysis of the pilot education series designed to increase primary care providers' knowledge of sexual health best practices including taking thorough sexual histories, STI screening and treatment, and PrEP prescribing. METHODS: A Sexual Health Curriculum Series was developed as part of a quality improvement initiative at a large urban safety-net hospital in Dallas County, Texas. Didactic sessions were administered to primary care providers and staff via a virtual meeting platform once a month from May 2021 to April 2022. RESULTS: A total of 52 participants completed the pre-series survey, and 21 participants filled out the final post-series survey. 70% of respondents who completed the post-series survey reported that they learned new information that was incorporated into their practice. The average percentage correct on individual pre-session surveys was 60% compared to 63% on individual post-session surveys (p = 0.03). CONCLUSION: Sexual health education is an important tool to help primary care providers adhere to sexual health best practices. There is a need for ongoing implementation of innovative strategies to improve knowledge and adherence to sexual health best practices. A sexual health curriculum may be effective in helping primary providers recognize patients at increased risk and apply evidence-based guidelines to their practices.

Addressing inequity in palliative care provision for older people living with multimorbidity. Perspectives of community-dwelling older people on their palliative care needs: A scoping review.

BACKGROUND: Older people living with multimorbidity are projected to become the main recipients of palliative care in the coming decades, yet there is limited evidence regarding their expressed palliative care needs to inform person-centred care. AIM: To understand the palliative care needs of community-dwelling people aged ⩾60 living with multimorbidity in the last 2 years of life. DESIGN: A scoping review following Arksey and O'Malley. DATA SOURCES: Three international electronic databases (CINAHL, Ovid Medline, PsycINFO) were searched from March 2018 to December 2021. Reference lists were hand searched. Eligible papers were those reporting empirical data on older people's needs. RESULTS: From 985 potential papers, 28 studies were included, published between 2002 and 2020; sixteen quantitative, nine qualitative and three mixed methods. Data were extracted and presented under the holistic palliative care domains of need: physical, psychological, social, spiritual, and additionally practical needs. Different measurement tools (n = 29) were used, of which 20 were multidimensional. Primacy in reporting was given to physical needs, most commonly pain and function. Social and practical needs were often prioritised by older people themselves, including maintaining social connections and accessing and receiving individualised care. CONCLUSION: Identifying the palliative care needs that matter most to older people with multimorbidity requires the recognition of their concerns, as well as their symptoms, across a continuum of living and dying. Available evidence is superficial. Supporting end of life provision for this growing and underserved population necessitates a shift to tailored multidimensional tools and community focussed integrated care services.

Safety and Efficacy of Ceftriaxone in the Treatment of Methicillin-Susceptible Staphylococcus aureus Bloodstream Infections: A Noninferiority Retrospective Cohort Study.

BACKGROUND: Antistaphylococcal penicillins and cefazolin are the treatments of choice for methicillin-susceptible Staphylococcus aureus (MSSA) infections, requiring multiple doses daily. At Parkland, eligible uninsured patients with MSSA bloodstream infections (BSI) receive self-administered outpatient parenteral antimicrobial therapy (S-OPAT). Ceftriaxone was used in a cohort of S-OPAT patients for ease of once-daily dosing. OBJECTIVE: A retrospective study was conducted to evaluate clinical outcomes for patients discharged with ceftriaxone versus cefazolin to treat MSSA BSI. METHODS: A retrospective cohort noninferiority study design was used to assess treatment efficacy of ceftriaxone versus cefazolin among Parkland S-OPAT patients treated from April 2012 to March 2020. Demographic, clinical, and treatment-related adverse events data were collected. Clinical outcomes included treatment failure as defined by repeat positive blood culture or retreatment within 6 months, all-cause 30-day readmission rates, and central line-associated bloodstream infection (CLABSI) rates. RESULTS: Of 368 S-OPAT patients with MSSA BSI, 286 (77.7%) received cefazolin, and 82 (22.3%) received ceftriaxone. Demographics and comorbidities were similar for both groups. There were no treatment failures in the ceftriaxone group compared with 4 (1%) in the cefazolin group (P = 0.58). No difference in 30-day readmission rate between groups was found. The CLABSI rates were lower in ceftriaxone group (2%) compared with cefazolin (11%; P = 0.02). Limitations include retrospective cohort design. CONCLUSIONS: Ceftriaxone was found to be noninferior to cefazolin in this study. Our findings suggest that ceftriaxone is a safe and effective treatment of MSSA BSI secondary to osteoarticular or skin and soft tissue infections when used in the S-OPAT setting. POSTER ABSTRACT: OFID on 2018 Nov; 5(Suppl 1): S316: doi: 10.1093/ofid/ofy210.894.

Impact of a clinical pharmacist within an HIV PrEP program for patients experiencing homelessness.

BACKGROUND: Human immunodeficiency virus (HIV) continues to be a concern in the United States despite pre-exposure prophylaxis (PrEP) being a highly recommended preventative option. Homeless populations have a significantly increased risk of HIV acquisition, and recent literature found attrition to PrEP care being concentrated in demographics common to these populations. Pharmacist-led PrEP programs may be a feasible option to combat this attrition, as they have shown high rates of patient satisfaction and pharmacist comfortability in other populations. OBJECTIVES: To evaluate PrEP uptake and the continuum of care before and after a Clinical Pharmacy Specialist (CPS) expanded HIV prevention services within a primary care setting for persons experiencing homelessness. METHODS: We compared a retrospective cohort of patients experiencing homelessness who received an initial PrEP prescription during a pre-CPS period and those with an initial PrEP prescription after CPS. Charts were reviewed through the surrounding time period of a 3-month and a 6-month PrEP follow-up appointment. Outcomes evaluated included number of initial PrEP prescriptions, dispensations of PrEP, PrEP discontinuations, patient retention in PrEP care, and new HIV diagnoses. RESULTS: A total of 40 patients were included, with 10 initial PrEP prescriptions in the pre-CPS population and 30 in the post-CPS one. Both groups largely represented those disproportionately impacted by HIV. After CPS, more patients were enrolled in patient assistance programs (100% vs. 44%; P < 0.01), and more patients picked up the first PrEP dispensation (80% vs. 40%; P = 0.04). The overall population had low dispensation rates and retention to care. Having no CPS management and a lack of medical appointment attendance trended toward attrition of care, and having no patient assistance program enrollment significantly led to attrition of care. CONCLUSION: These findings may prompt further studies and adaptations to PrEP care among persons experiencing homelessness, including the utilization of pharmacists to improve patient outcomes.

Mind the Interface Gap: Exposing Hidden Interface Defects at the Epitaxial Heterostructure between CuO and Cu2O.

Well designed and optimized epitaxial heterostructures lie at the foundation of materials development for photovoltaic, photocatalytic, and photoelectrochemistry applications. Heterostructure materials offer tunable control over charge separation and transport at the same time preventing recombination of photogenerated excitations at the interface. Thus, it is of paramount importance that a detailed understanding is developed as the basis for further optimization strategies and design. Oxides of copper are nontoxic, low cost, abundant materials with a straightforward and stable manufacturing process. However, in individual applications, they suffer from inefficient charge transport of photogenerated carriers. Hence, in this work, we investigate the role of the interface between epitaxially aligned CuO and Cu2O to explore the potential benefits of such an architecture for more efficient electron and hole transfer. The CuO/Cu2O heterojunction nature, stability, bonding mechanism, interface dipole, electronic structure, and band bending were rationalized using hybrid density functional theory calculations. New electronic states are identified at the interface itself, which are originating neither from lattice mismatch nor strained Cu-O bonds. They form as a result of a change in coordination environment of CuO surface Cu2+ cations and an electron transfer across the interface Cu1+-O bond. The first process creates occupied defect-like electronic states above the valence band, while the second leaves hole states below the conduction band. These are constitutional to the interface and are highly likely to contribute to recombination effects competing with the improved charged separation from the suitable band bending and alignment and thus would limit the expected output photocurrent and photovoltage. Finally, a favorable effect of interstitial oxygen defects has been shown to allow for band gap tunability at the interface but only to the point of the integral geometrical contact limit of the heterostructure itself.

Animal hoarding cases in England: Implications for public health services.

Hoarding disorder is characterized by an accumulation of possessions due to excessive acquisition of or difficulty discarding possessions, regardless of their actual value and is estimated to affect 2-6% of the population. Animal hoarding, a distinct subset of hoarding disorder, has a significant public health impact on the humans involved, as well as animal welfare. Individuals exhibit self-neglect, apathy, social withdrawal and object hoarding; living within squalid, deteriorated, structurally unsafe and uninhabitable premises, alongside neglected animals. Cases are complex, costly and impact on a range of responding service providers. Effective case management is poorly understood and researched, with published literature in England particularly sparse. Improving understanding of the characteristics of these cases is the first step in informed case management. This research is the first exploration of the characteristics of animal hoarders in England and the areas where cases were located. Information about prosecutions involving large numbers of animals that were reported in the media was systematically obtained. This identified 66 cases between January 2015 and December 2020. Geospatial analysis exploring characteristics of locations where animal hoarding cases are also reported. Findings were broadly consistent with the international literature in that females (64%), those living alone (71%) and those with a mean age of 49 were well represented. Cats (61.5%) and dogs (60%) were the most commonly hoarded species. There was a mean of 44 animals per case and dead or animals requiring euthanasia found in 53% of cases. Key characteristics of the areas where cases were found highlight urban, densely populated, and high levels of deprivation being the most represented. Evidence of recidivism was evident in 39% of cases, suggesting that prosecution is not an effective rehabilitator. Animal hoarding raises serious implications for Public Health Services, and the lack of current effective case management strategies are discussed.

Implementation of Outpatient Infectious Diseases E-Consults at a Safety Net Healthcare System.

Background: Safety net healthcare systems have high patient volumes and significant demands for specialty care including infectious diseases (ID) consultations. Electronic ID consults (E-consults) can lessen this burden by providing an alternative to face-to-face ID referrals and decreasing financial, time, and travel constraints on patients. This system could increase access to ID care for patients in limited-resource settings. Methods: We described characteristics of all outpatient ID E-consults at Parkland Health in Dallas, Texas, from March 2018 to February 2021. We used modeling to determine which characteristics influenced conversion of E-consults to clinic visits and integrated these data into a predictive model for face-to-face conversion. Results: For 725 E-consults, common E-consult topics included 118 (16%) latent tuberculosis, 116 (16%) syphilis, and 76 (10%) gastrointestinal infections. Nearly two-thirds of E-consults (456 [63%]) were requested by primary care providers. The majority (78%) were resolved without a face-to-face ID visit. Osteomyelitis, nontuberculous mycobacterial, and gastrointestinal questions frequently required face-to-face visits at rates of 65%, 49%, and 32%, respectively. Our logistic regression model predicted the need for a face-to-face visit with 80% accuracy and an area under the receiver operating characteristic curve of 0.72. Conclusions: An outpatient ID E-consult program at a safety net healthcare system was an effective tool to provide timely input on common ID topics. E-consults were requested by a range of providers, and most were completed without a face-to-face visit. Predictive modeling identified important characteristics of E-consults and predicted conversion to face-to-face visits with reasonable accuracy.

Experimental and Theoretical Constraints on Amino Acid Formation from PAHs in Asteroidal Settings.

Amino acids and polycyclic aromatic hydrocarbons (PAHs) belong to the range of organic compounds detected in meteorites. In this study, we tested empirically and theoretically if PAHs are precursors for amino acids in carbonaceous chondrites, as previously suggested. We conducted experiments to synthesize amino acids from fluoranthene (PAH), with ammonium bicarbonate as a source for ammonia and carbon dioxide under mimicked asteroidal conditions. In our thermodynamic calculations, we extended our analysis to additional PAH-amino acid combinations. We explored 36 reactions involving the PAHs naphthalene, anthracene, fluoranthene, pyrene, triphenylene, and coronene and the amino acids glycine, alanine, valine, leucine, phenylalanine, and tyrosine. Our experiments do not show the formation of amino acids, whereas our theoretical results hint that PAHs could be precursors of amino acids in carbonaceous chondrites at low temperatures.

Characteristics and Outcomes of Infectious Diseases Electronic COVID-19 Consultations at a Multisite Academic Health System.

Objective The need for clinicians to access Infectious Diseases (ID) consultants for clinical decision-making support increased during the Coronavirus Disease 2019 (COVID-19) pandemic. Traditional ID consultations with face-to-face (FTF) patient assessments are not always possible or practical during a pandemic and involve added exposure risk and personal protective equipment (PPE) use. Electronic consultations (e-consults) may provide an alternative and improve access to ID specialists during the pandemic. Methods We implemented ID e-consult platforms designed to answer clinical questions related to COVID-19 at three academic clinical institutions in Dallas, Texas. We conducted a retrospective review of all COVID-19 ID e-consults between March 16, 2020 and May 15, 2020 evaluating characteristics and outcomes of e-consults among the clinical sites. Results We completed 198 COVID-19 ID e-consults at participating institutions. The most common e-consult indications were for 63 (32%) repeat testing, 61 (31%) initial testing, 65 (33%) treatment options, and 61 (31%) Infection Prevention (IP). Based on the e-consult recommendation, 53 (27%) of patients were initially tested for COVID-19, 45 (23%) were re-tested, 44 (22%) of patients had PPE precautions initiated, and 37 (19%) had PPE precautions removed. The median time to consult completion was four hours and 8 (4%) consults were converted to standard FTF consults. Conclusion E-consult services can provide safe and timely access to ID specialists during the COVID-19 pandemic, minimizing the risk of infection to the patient and health care workers, while preserving PPE and testing supplies.

Magnetic structure and exchange interactions in pyrrhotite end member minerals: hexagonal FeS and monoclinic Fe7S8.

Iron mono-sulphides, or pyrrhotites, are minerals present in the Earth's crust and mantle as well as major magnetic constituents of several classes of meteorites, thus are of interest to a wide range of disciplines including geology, geophysics, geochemistry, and material science. Despite displaying diverse magnetic properties as a result of iron vacancy ordering, the underlying exchange mechanism has not been quantified. This study presents an examination of the electronic and magnetic properties for the two pyrrhotite group end members, hexagonal FeS and monoclinic Fe7S8(4C superstructure) by means of density functional theory coupled with a Heisenberg magnetic model. The easy magnetization axes of FeS and Fe7S8are found to be positioned along the crystallographicc-direction and at an angle of 56° to thec-direction, respectively. The magnetic anisotropy energy in Fe7S8is greatly increased as a consequence of the vacancy framework when compared to FeS. The main magnetic interaction, in both compounds, is found to be the isotropic exchange interaction favouring antiferromagnetic alignment between nearest-neighbouring spins. The origin of the exchange interaction is elucidated further following the Goodenough-Kanamori-Anderson rules. The antisymmetric spin exchange is found to have a minor effect in both compounds. The theoretical findings presented in this work thus help to further resolve some of the ambiguities in the magnetic features of pyrrhotites.

Decreasing Chlamydial Reinfections in a Female Urban Population.

BACKGROUND: Chlamydia is the most reported bacterial sexually transmitted infection (STI). The rates of chlamydia rose by 19% between 2011 and 2018. The STI National Strategic Plan (2021-2025), encourages coordinated solutions to address STIs and reduce disparities in disadvantaged populations. METHODS: We implemented institutional policy changes, clinical decision support, including a Best Practice Advisory, and defaulted SmartSet with provider and patient education for women's health clinics at a large county health system. The advisory prompted providers to follow best practices when treating Chlamydia trachomatis infections. New C. trachomatis diagnosis cohorts were compared preintervention and postintervention for 6-month reinfection rates and patient and expedited partner treatment (EPT) practices. RESULTS: Five hundred and nineteen women were included in the final analysis. Six-month chlamydia reinfection was lower in the postintervention cohort after adjusting for age (12.3% [26/211] vs 6.5% [20/308], P = 0.02). There was an increase in directly observed therapy of primary patients (17.5% [37/211] vs 77.3% [238/308], P < 0.001), an increase in EPT prescriptions written (4.3% [9/211] vs 79.5% [245/308], P < 0.0001), and a decrease of partners referred out for treatment (61.6% [130/211] vs 5.2% [16/308], P < 0.001) when compared with the control group. The majority of EPT was patient-delivered partner therapy postintervention (3.3% [7/211] vs 69.2% [213/308], P < 0.001). CONCLUSIONS: A multifaceted, streamlined approach was effective in changing provider practices in the treatment of C. trachomatis. Increased rates of directly observed therapy for primary patient treatment and increased rates of patient-delivered partner therapy were observed postimplementation in addition to lower 6-month reinfection rates in a public women's health clinic setting.

PrEP University: A Multi-Disciplinary University-Based HIV Prevention Education Program.

The introduction of emtricitabine/tenofovir diphosphate (FTC/TDF) as pre-exposure prophylaxis (PrEP) for HIV prevention has raised questions regarding which clinicians will serve as prescribers and how providers will be educated about this HIV prevention strategy. We piloted an HIV Prevention Education Program called PrEP University (PrEP U) to address knowledge gaps in HIV prevention among medical trainees. We examined PrEP awareness and assessed learning as a result of the program, measuring knowledge before and after the lectures with an anonymous 5-question multiple choice test. A total of 198 learners participated in PrEP University, which included 127 first year medical students, and post-graduate trainees in internal medicine (n = 23), family medicine (n = 16), OBGYN (n = 13) and pharmacy (n = 19). Prior to PrEP U, 27% of all participants were not aware of PrEP and an additional 8% were unsure if they had heard of it. Knowledge increased significantly after the education program among trainees in OBGYN (2.3 vs 3.8, p < 0.001), pharmacy (1.4 vs 2.5, p = 0.012) and school of medicine (3.3 vs 4.4, p < 0.001), with a trend seen in family medicine (2.7 vs. 3.7, p = 0.067) and internal medicine (2.7 vs 3.4, p = 0.068). Overall, an HIV Prevention Education Program was successfully administered to nearly 200 participants and resulted in improved knowledge of HIV prevention and PrEP across. Pharmacists and OBGYN physicians are two groups with an expanding role in the use of PrEP. Similar programs at other medical schools should be implemented to ensure that future physicians and pharmacists are comfortable with PrEP prescription.

Structure of human RNA polymerase III.

In eukaryotes, RNA Polymerase (Pol) III is specialized for the transcription of tRNAs and other short, untranslated RNAs. Pol III is a determinant of cellular growth and lifespan across eukaryotes. Upregulation of Pol III transcription is observed in cancer and causative Pol III mutations have been described in neurodevelopmental disorders and hypersensitivity to viral infection. Here, we report a cryo-EM reconstruction at 4.0 Å of human Pol III, allowing mapping and rationalization of reported genetic mutations. Mutations causing neurodevelopmental defects cluster in hotspots affecting Pol III stability and/or biogenesis, whereas mutations affecting viral sensing are located in proximity to DNA binding regions, suggesting an impairment of Pol III cytosolic viral DNA-sensing. Integrating x-ray crystallography and SAXS, we also describe the structure of the higher eukaryote specific RPC5 C-terminal extension. Surprisingly, experiments in living cells highlight a role for this module in the assembly and stability of human Pol III.

Influence of Inorganic Solution Components on Lithium Carbonate Crystal Growth.

Lithium-bearing brines are an increasingly attractive source of Li for extraction. One extraction mechanism is the removal of Li from the fluid phase through the precipitation of zabuyelite (Li2CO3). The chemistry of the brine plays an important role in this process because ions in solution can compete for the components of the Li-carbonate phase. Here we explore the effect of different brine components on the precipitation of zabuyelite using experiments and computational simulations. Crystals formed in all solutions showed morphological evidence for potential transformation from a precursor phase. Our study indicates that Ca2+ and SO4 2- are incorporated into the precipitated zabuyelite crystals. Sulfate also interacts directly with specific surfaces on the growing crystal and is expected to form ion pairs with Li+ in solution. Similarly, Na+ appears to form ion pairs in solution with the carbonate ion, slowing nucleation of zabuyelite in the experiments. K+ and Cl- may interact with the growing zabuyelite crystals but do not appear to affect zabuyelite nucleation and growth times. These experiments highlight the importance of understanding the solution chemistry on zabuyelite formation in order to predict the efficiency of extraction processes and the purity of the solids.

Correlative vibrational spectroscopy and 2D X-ray diffraction to probe the mineralization of bone in phosphate-deficient mice.

Bone crystallite chemistry and structure change during bone maturation. However, these properties of bone can also be affected by limited uptake of the chemical constituents of the mineral by the animal. This makes probing the effect of bone-mineralization-related diseases a complicated task. Here it is shown that the combination of vibrational spectroscopy with two-dimensional X-ray diffraction can provide unparalleled information on the changes in bone chemistry and structure associated with different bone pathologies (phosphate deficiency) and/or health conditions (pregnancy, lactation). Using a synergistic analytical approach, it was possible to trace the effect that changes in the remodelling regime have on the bone mineral chemistry and structure in normal and mineral-deficient (hypophosphatemic) mice. The results indicate that hypophosphatemic mice have increased bone remodelling, increased carbonate content and decreased crystallinity of the bone mineral, as well as increased misalignment of crystallites within the bone tissue. Pregnant and lactating mice that are normal and hypophosphatemic showed changes in the chemistry and misalignment of the apatite crystals that can be related to changes in remodelling rates associated with different calcium demand during pregnancy and lactation.

Dominant, Heritable Resistance to Stewart's Wilt in Maize Is Associated with an Enhanced Vascular Defense Response to Infection with Pantoea stewartii.

Vascular wilt bacteria such as Pantoea stewartii, the causal agent of Stewart's bacterial wilt of maize (SW), are destructive pathogens that are difficult to control. These bacteria colonize the xylem, where they form biofilms that block sap flow leading to characteristic wilting symptoms. Heritable forms of SW resistance exist and are used in maize breeding programs but the underlying genes and mechanisms are mostly unknown. Here, we show that seedlings of maize inbred lines with pan1 mutations are highly resistant to SW. However, current evidence suggests that other genes introgressed along with pan1 are responsible for resistance. Genomic analyses of pan1 lines were used to identify candidate resistance genes. In-depth comparison of P. stewartii interaction with susceptible and resistant maize lines revealed an enhanced vascular defense response in pan1 lines characterized by accumulation of electron-dense materials in xylem conduits visible by electron microscopy. We propose that this vascular defense response restricts P. stewartii spread through the vasculature, reducing both systemic bacterial colonization of the xylem network and consequent wilting. Though apparently unrelated to the resistance phenotype of pan1 lines, we also demonstrate that the effector WtsE is essential for P. stewartii xylem dissemination, show evidence for a nutritional immunity response to P. stewartii that alters xylem sap composition, and present the first analysis of maize transcriptional responses to P. stewartii infection.

3D Raman Spectroscopy of Large Zeolite ZSM-5 Crystals.

Hydrothermal treatment is a common method used to modify the physicochemical properties of zeolite-based catalyst materials. It alters the number and type of acid sites through dealumination and increases molecular diffusion by mesopore formation. Steaming also reduces the structural integrity of zeolite frameworks. In this study, Raman microscopy has been used to map large zeolite ZSM-5 crystals before and after steaming. 3D elemental maps of T-O (T: Al or Si) sites of the zeolite were obtained. The Raman active vibrational bands were determined, which are indicative of (non-) framework Al, as well as of structural integrity. Zeolite steaming caused the introduction of additional heterogeneities within the zeolite framework. Al migration and the formation of extra-framework Al species were observed. The described experiments demonstrate the capability of 3D Raman spectroscopy as a valuable tool to obtain information on the spatial distributions of framework elements as well as defects within a zeolite-based material.