Spectroscopic Evidence of Kondo-Induced Quasiquartet in CeRh_{2}As_{2}.

CeRh_{2}As_{2} is a new multiphase superconductor with strong suggestions for an additional itinerant multipolar ordered phase. The modeling of the low-temperature properties of this heavy-fermion compound requires a quartet Ce^{3+} crystal-field ground state. Here, we provide the evidence for the formation of such a quartet state using x-ray spectroscopy. Core-level photoelectron and x-ray absorption spectroscopy confirm the presence of Kondo hybridization in CeRh_{2}As_{2}. The temperature dependence of the linear dichroism unambiguously reveals the impact of Kondo physics for coupling the Kramer's doublets into an effective quasiquartet. Nonresonant inelastic x-ray scattering data find that the |Γ_{7}^{-}⟩ state with its lobes along the 110 direction of the tetragonal structure (xy orientation) contributes most to the multiorbital ground state of CeRh_{2}As_{2}.

Understanding clinical outcomes and factors influencing mortality in intensive care unit patients with COVID-19-associated candidemia.

BACKGROUND: During the COVID pandemic, research has shown an increase in candidemia cases following severe COVID infection and the identification of risk factors associated with candidemia. However, there is a lack of studies that specifically explore clinical outcomes and mortality rates related to candidemia after COVID infection. OBJECTIVES: The aim of this international study was to evaluate the clinical outcomes and identify factors influencing mortality in patients who developed candidemia during their COVID infection. PATIENTS/METHODS: This study included adult patients (18 years of age or older) admitted to the intensive care unit (ICU) and diagnosed with COVID-associated candidemia (CAC). The research was conducted through ID-IRI network and in collaboration with 34 medical centres across 18 countries retrospectively, spanning from the beginning of the COVID pandemic until December 2021. RESULTS: A total of 293 patients diagnosed with CAC were included. The median age of the patients was 67, and 63% of them were male. The most common Candida species detected was C. albicans. The crude 30-day mortality rate was recorded at 62.4%. The logistic regression analysis identified several factors significantly impacting mortality, including age (odds ratio [OR] 1.04, 95% confidence interval [CI] 1.02-1.07, p < .0005), SOFA score (OR 1.307, 95% CI 1.17-1.45, p < .0005), invasive mechanical ventilation (OR 7.95, 95% CI 1.44-43.83, p < .017) and duration of mechanical ventilation (OR 0.98, 95% CI 0.96-0.99, p < .020). CONCLUSIONS: By recognising these prognostic factors, medical professionals can customise their treatment approaches to offer more targeted care, leading to improved patient outcomes and higher survival rates for individuals with COVID-associated candidemia.

Navigating the Nexus: HIV and Breast Cancer-A Critical Review.

Despite significant advances in the management of antiretroviral therapy (ART), leading to improved life expectancy for people living with HIV (PLWH), the incidence of non-AIDS-defining cancers, including breast cancer, has emerged as a critical concern. This review synthesizes current evidence on the epidemiology of breast cancer among HIV-infected individuals, highlighting the potential for an altered risk profile, earlier onset, and more advanced disease at diagnosis. It delves into the molecular considerations underpinning the relationship between HIV and breast cancer, including the role of immunosuppression, chronic inflammation, and gene expression alterations. Additionally, it examines the complexities of managing breast cancer in the context of HIV, particularly the challenges posed by ART and anticancer agents' cross-toxicities and drug-drug interactions. The review also addresses survival disparities, underscoring the need for improved cancer care in this population. By identifying gaps in knowledge and areas requiring further research, this review aims to illuminate the complexities of HIV-associated breast cancer, fostering a deeper understanding of its epidemiology, molecular basis, and clinical management challenges, thereby contributing to better outcomes for individuals at the intersection of these two conditions. This narrative review systematically explores the intersection of HIV infection and breast cancer, focusing on the impact of HIV on breast cancer risk, outcomes, and treatment challenges.

Mortality Attributable to Bloodstream Infections Caused by Different Carbapenem-Resistant Gram-Negative Bacilli: Results From a Nationwide Study in Italy (ALARICO Network).

BACKGROUND: Our aim was to analyze mortality attributable to carbapenem-resistant (CR) gram-negative bacilli (GNB) in patients with bloodstream infections (BSIs). METHODS: Prospective multicentric study including patients with GNB-BSI from 19 Italian hospitals (June 2018-January 2020). Patients were followed-up to 30 days. Primary outcomes were 30-day mortality and attributable mortality. Attributable mortality was calculated in the following groups: Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacterales, metallo-ß-lactamases (MBL)-producing Enterobacterales, CR-Pseudomonas aeruginosa (CRPA), CR-Acinetobacter baumannii (CRAB). A multivariable analysis with hospital fixed-effect was built to identify factors associated with 30-day mortality. Adjusted OR (aORs) were reported. Attributable mortality was calculated according to the DRIVE-AB Consortium. RESULTS: Overall, 1276 patients with monomicrobial GNB BSI were included: 723/1276 (56.7%) carbapenem-susceptible (CS)-GNB, 304/1276 (23.8%) KPC-, 77/1276 (6%) MBL-producing CRE, 61/1276 (4.8%) CRPA, and 111/1276 (8.7%) CRAB BSI. Thirty-day mortality in patients with CS-GNB BSI was 13.7% compared to 26.6%, 36.4%, 32.8% and 43.2% in patients with BSI by KPC-CRE, MBL-CRE, CRPA and CRAB, respectively (P < .001). On multivariable analysis, age, ward of hospitalization, SOFA score, and Charlson Index were factors associated with 30-day mortality, while urinary source of infection and early appropriate therapy resulted protective factors. Compared to CS-GNB, MBL-producing CRE (aOR 5.86, 95% CI 2.72-12.76), CRPA (aOR 1.99, 95% CI 1.48-5.95) and CRAB (aOR 2.65, 95% CI 1.52-4.61) were significantly associated with 30-day mortality. Attributable mortality rates were 5% for KPC-, 35% for MBL, 19% for CRPA, and 16% for CRAB. CONCLUSIONS: In patients with BSIs, carbapenem-resistance is associated with an excess of mortality, with MBL-producing CRE carrying the highest risk of death.

Classical fever of unknown origin in 21 countries with different economic development: an international ID-IRI study.

Fever of unknown origin (FUO) is a serious challenge for physicians. The aim of the present study was to consider epidemiology and dynamics of FUO in countries with different economic development. The data of FUO patients hospitalized/followed between 1st July 2016 and 1st July 2021 were collected retrospectively and submitted from referral centers in 21 countries through ID-IRI clinical research platform. The countries were categorized into developing (low-income (LI) and lower middle-income (LMI) economies) and developed countries (upper middle-income (UMI) and high-income (HI) economies). This research included 788 patients. FUO diagnoses were as follows: infections (51.6%; n = 407), neoplasms (11.4%, n = 90), collagen vascular disorders (9.3%, n = 73), undiagnosed (20.1%, n = 158), miscellaneous diseases (7.7%, n = 60). The most common infections were tuberculosis (n = 45, 5.7%), brucellosis (n = 39, 4.9%), rickettsiosis (n = 23, 2.9%), HIV infection (n = 20, 2.5%), and typhoid fever (n = 13, 1.6%). Cardiovascular infections (n = 56, 7.1%) were the most common infectious syndromes. Only collagen vascular disorders were reported significantly more from developed countries (RR = 2.00, 95% CI: 1.19-3.38). FUO had similar characteristics in LI/LMI and UMI/HI countries including the portion of undiagnosed cases (OR, 95% CI; 0.87 (0.65-1.15)), death attributed to FUO (RR = 0.87, 95% CI: 0.65-1.15, p-value = 0.3355), and the mean duration until diagnosis (p = 0.9663). Various aspects of FUO cannot be determined by the economic development solely. Other development indices can be considered in future analyses. Physicians in different countries should be equally prepared for FUO patients.

Clinicopathological profile of peritoneal tuberculosis and a new scoring model for predicting mortality: an international ID-IRI study.

Existing literature about peritoneal tuberculosis (TBP) is relatively insufficient. The majority of reports are from a single center and do not assess predictive factors for mortality. In this international study, we investigated the clinicopathological characteristics of a large series of patients with TBP and determined the key features associated with mortality. TBP patients detected between 2010 and 2022 in 38 medical centers in 13 countries were included in this retrospective cohort. Participating physicians filled out an online questionnaire to report study data. In this study, 208 patients with TBP were included. Mean age of TBP cases was 41.4 ± 17.5 years. One hundred six patients (50.9%) were females. Nineteen patients (9.1%) had HIV infection, 45 (21.6%) had diabetes mellitus, 30 (14.4%) had chronic renal failure, 12 (5.7%) had cirrhosis, 7 (3.3%) had malignancy, and 21 (10.1%) had a history of immunosuppressive medication use. A total of 34 (16.3%) patients died and death was attributable to TBP in all cases. A pioneer mortality predicting model was established and HIV positivity, cirrhosis, abdominal pain, weakness, nausea and vomiting, ascites, isolation of Mycobacterium tuberculosis in peritoneal biopsy samples, TB relapse, advanced age, high serum creatinine and ALT levels, and decreased duration of isoniazid use were significantly related with mortality (p < 0.05). This is the first international study on TBP and is the largest case series to date. We suggest that using the mortality predicting model will allow early identification of high-risk patients likely to die of TBP.

From antiferromagnetic and hidden order to Pauli paramagnetism in UM 2Si2 compounds with 5f electron duality.

Using inelastic X-ray scattering beyond the dipole limit and hard X-ray photoelectron spectroscopy we establish the dual nature of the U [Formula: see text] electrons in U[Formula: see text] (M = Pd, Ni, Ru, Fe), regardless of their degree of delocalization. We have observed that the compounds have in common a local atomic-like state that is well described by the U [Formula: see text] configuration with the [Formula: see text] and [Formula: see text] quasi-doublet symmetry. The amount of the U 5[Formula: see text] configuration, however, varies considerably across the U[Formula: see text] series, indicating an increase of U 5f itineracy in going from M = Pd to Ni to Ru and to the Fe compound. The identified electronic states explain the formation of the very large ordered magnetic moments in [Formula: see text] and [Formula: see text], the availability of orbital degrees of freedom needed for the hidden order in [Formula: see text] to occur, as well as the appearance of Pauli paramagnetism in [Formula: see text] A unified and systematic picture of the U[Formula: see text] compounds may now be drawn, thereby providing suggestions for additional experiments to induce hidden order and/or superconductivity in U compounds with the tetragonal body-centered [Formula: see text] structure.

Updates in central nervous system malaria: literature review and considerations.

PURPOSE OF REVIEW: Cerebral malaria (CM) represents one of the most common and severe complications of Plasmodium falciparum infection, leading to high morbidity and mortality along with challenging sequelae, especially in children. RECENT FINDINGS: Although CM pathogenesis remains unclear due to the few studies made and the difficulty to analyze affected patients, there are valid theories involving P. falciparum endothelium interactions, and clinical manifestations have been better investigated and differentiated between adults and children. SUMMARY: At the time of writing, diagnostic management is based on fast severe malaria identification by blood smear (thin and thick). However, newer techniques involving molecular testing (such as PCR or LAMP) and biomarkers identification are now available. It is also important to check patients' cerebral functions. As regards therapeutic management, although we could rely on several options, artesunate represents the gold standard treatment. Cerebral complications such as seizures and coma need to be managed as well.

Profiles of multidrug-resistant organisms among patients with bacteremia in intensive care units: an international ID-IRI survey.

Evaluating trends in antibiotic resistance is a requisite. The study aimed to analyze the profile of multidrug-resistant organisms (MDROs) among hospitalized patients with bacteremia in intensive care units (ICUs) in a large geographical area. This is a 1-month cross-sectional survey for blood-borne pathogens in 57 ICUs from 24 countries with different income levels: lower-middle-income (LMI), upper-middle-income (UMI), and high-income (HI) countries. Multidrug-resistant (MDR), extensively drug-resistant (XDR), or pan-drug-resistant isolates were searched. Logistic regression analysis determined resistance predictors among MDROs. Community-acquired infections were comparable to hospital-acquired infections particularly in LMI (94/202; 46.5% vs 108/202; 53.5%). Although MDR (65.1%; 502/771) and XDR (4.9%; 38/771) were common, no pan-drug-resistant isolate was recovered. In total, 32.1% of MDR were Klebsiella pneumoniae, and 55.3% of XDR were Acinetobacter baumannii. The highest MDR and XDR rates were in UMI and LMI, respectively, with no XDR revealed from HI. Predictors of MDR acquisition were male gender (OR, 12.11; 95% CI, 3.025-15.585) and the hospital-acquired origin of bacteremia (OR, 2.643; 95%CI, 1.462-3.894), and XDR acquisition was due to bacteremia in UMI (OR, 3.344; 95%CI, 1.189-5.626) and admission to medical-surgical ICUs (OR, 1.481; 95% CI, 1.076-2.037). We confirm the urgent need to expand stewardship activities to community settings especially in LMI, with more paid attention to the drugs with a higher potential for resistance. Empowering microbiology laboratories and reports to direct prescribing decisions should be prioritized. Supporting stewardship in ICUs, the mixed medical-surgical ones in particular, is warranted.

Malignant melanoma in HIV: Epidemiology, pathogenesis, and management.

People affected by immunodeficiency, and especially those infected by HIV, are burdened by a higher risk of developing malignancies. It has been estimated that the incidence of melanoma in HIV-infected people is 2.6-fold higher than in uninfected ones. In this group of patients, melanoma shows a more aggressive phenotype and poorer survival rates compared to HIV-negative people. Standard guidelines of diagnosis and care do not exist yet. Studies suggest high index of suspicion and a low threshold for biopsy in HIV-positive patients regardless of their CD4+ count and the use of standard surgical margins for re-excision procedures. In case of diagnosis of melanoma in HIV-positive patients, a thorough search for metastatic disease is recommended because of the more aggressive course of this cancer in HIV-positive patients. Moreover, to rapidly find out any recurrence or metastatic disease after treatment, these patients need a close follow-up, every 3 months, for the first 2 years and at least twice yearly thereafter. Although surgery remains the main therapeutic option, application of immune checkpoint-based immunotherapy is being studied and seems to be promising. The aim of this review is to present the current knowledge and future options for melanoma diagnosis and treatment in people living with HIV.

Rapid emergence of cryptococcal fungemia, Mycobacterium chelonae vertebral osteomyelitis and gastro intestinal stromal tumor in a young HIV late presenter: a case report.

BACKGROUND: Highly active antiretroviral therapy has significantly changed the natural history of HIV infection, leading to a dramatic reduction of HIV-related morbidity and mortality. Late Presenters, Very Late Presenters and AIDS presenters still represent, also in Europe, including Italy, a huge challenge in terms of diagnostic and therapeutic management. CASE PRESENTATION: A 35-year-old male with a history of fever and back pain. HIV test resulted positive with a high HIV Viral Load and a very low T-CD4 number of cells (5 cells/mm3). Imaging investigations revealed multiple vertebral and pulmonary lesions together with abdominal and thoracic lymphadenopathy. Blood cultures were positive for Cryptococcus neoformans and for Staphylococcus haemolyticus. Lymphnode biopsy resulted positive in PCR for Non-Tuberculosis Mycobacteria (Mycobacterium chelonae). A gastric biopsy also revealed a GIST. The patient also had CMV DNA positive. Although we performed antiretroviral therapy and specific-therapies for each disease, he was transferred to intensive care unit where he died due to an Acute Respiratory Distress Syndrome. CONCLUSION: The reported case is unusual due to the relevant number of opportunistic diseases (both infectious and tumoral) emerging not long after the HIV infection had been diagnosed. Late presenters HIV patients and AIDS presenters still represent a challenge, which is often too complex for clinicians to deal with. In spite of proper management, the risk of suboptimal results cannot be excluded.

Impact of liver fat on the differential partitioning of hepatic triacylglycerol into VLDL subclasses on high and low sugar diets.

Dietary sugars are linked to the development of non-alcoholic fatty liver disease (NAFLD) and dyslipidaemia, but it is unknown if NAFLD itself influences the effects of sugars on plasma lipoproteins. To study this further, men with NAFLD (n = 11) and low liver fat 'controls' (n = 14) were fed two iso-energetic diets, high or low in sugars (26% or 6% total energy) for 12 weeks, in a randomised, cross-over design. Fasting plasma lipid and lipoprotein kinetics were measured after each diet by stable isotope trace-labelling.There were significant differences in the production and catabolic rates of VLDL subclasses between men with NAFLD and controls, in response to the high and low sugar diets. Men with NAFLD had higher plasma concentrations of VLDL1-triacylglycerol (TAG) after the high (P<0.02) and low sugar (P<0.0002) diets, a lower VLDL1-TAG fractional catabolic rate after the high sugar diet (P<0.01), and a higher VLDL1-TAG production rate after the low sugar diet (P<0.01), relative to controls. An effect of the high sugar diet, was to channel hepatic TAG into a higher production of VLDL1-TAG (P<0.02) in the controls, but in contrast, a higher production of VLDL2-TAG (P<0.05) in NAFLD. These dietary effects on VLDL subclass kinetics could be explained, in part, by differences in the contribution of fatty acids from intra-hepatic stores, and de novo lipogenesis. The present study provides new evidence that liver fat accumulation leads to a differential partitioning of hepatic TAG into large and small VLDL subclasses, in response to high and low intakes of sugars.

Telling metabolic stories to explore metabolomics data: a case study on the yeast response to cadmium exposure.

MOTIVATION: The increasing availability of metabolomics data enables to better understand the metabolic processes involved in the immediate response of an organism to environmental changes and stress. The data usually come in the form of a list of metabolites whose concentrations significantly changed under some conditions, and are thus not easy to interpret without being able to precisely visualize how such metabolites are interconnected. RESULTS: We present a method that enables to organize the data from any metabolomics experiment into metabolic stories. Each story corresponds to a possible scenario explaining the flow of matter between the metabolites of interest. These scenarios may then be ranked in different ways depending on which interpretation one wishes to emphasize for the causal link between two affected metabolites: enzyme activation, enzyme inhibition or domino effect on the concentration changes of substrates and products. Equally probable stories under any selected ranking scheme can be further grouped into a single anthology that summarizes, in a unique subnetwork, all equivalently plausible alternative stories. An anthology is simply a union of such stories. We detail an application of the method to the response of yeast to cadmium exposure. We use this system as a proof of concept for our method, and we show that we are able to find a story that reproduces very well the current knowledge about the yeast response to cadmium. We further show that this response is mostly based on enzyme activation. We also provide a framework for exploring the alternative pathways or side effects this local response is expected to have in the rest of the network. We discuss several interpretations for the changes we see, and we suggest hypotheses that could in principle be experimentally tested. Noticeably, our method requires simple input data and could be used in a wide variety of applications. AVAILABILITY AND IMPLEMENTATION: The code for the method presented in this article is available at http://gobbolino.gforge.inria.fr.

Ecological drivers of guanaco recruitment: variable carrying capacity and density dependence.

Ungulates living in predator-free reserves offer the opportunity to study the influence of food limitation on population dynamics without the potentially confounding effects of top-down regulation or livestock competition. We assessed the influence of relative forage availability and population density on guanaco recruitment in two predator-free reserves in eastern Patagonia, with contrasting scenarios of population density. We also explored the relative contribution of the observed recruitment to population growth using a deterministic linear model to test the assumption that the studied populations were closed units. The observed densities increased twice as fast as our theoretical populations, indicating that marked immigration has taken place during the recovery phase experienced by both populations, thus we rejected the closed-population assumption. Regarding the factors driving variation in recruitment, in the low- to medium-density setting, we found a positive linear relationship between recruitment and surrogates of annual primary production, whereas no density dependence was detected. In contrast, in the high-density scenario, both annual primary production and population density showed marked effects, indicating a positive relationship between recruitment and per capita food availability above a food-limitation threshold. Our results support the idea that environmental carrying capacity fluctuates in response to climatic variation, and that these fluctuations have relevant consequences for herbivore dynamics, such as amplifying density dependence in drier years. We conclude that including the coupling between environmental variability in resources and density dependence is crucial to model ungulate population dynamics; to overlook temporal changes in carrying capacity may even mask density dependence as well as other important processes.

The role of ligand-field states in the ultrafast photophysical cycle of the prototypical iron(II) spin-crossover compound [Fe(ptz)(6)](BF(4))(2).

Light-induced excited spin-state trapping (LIESST) in iron(II) spin-crossover compounds, that is, the light-induced population of the high-spin (S=2) state below the thermal transition temperature, was discovered thirty years ago. For irradiation into metal-ligand charge transfer (MLCT) bands of the low-spin (S=0) species the acknowledged sequence takes the system from the initially excited (1) MLCT to the high-spin state via the (3) MLCT state within ca. 150 fs, thereby bypassing low-lying ligand-field (LF) states. Nevertheless, these play a role, as borne out by the observation of LIESST and reverse-LIESST on irradiation directly into the LF bands for systems with only high-energy MLCT states. Herein we elucidate the ultrafast reverse-LIESST pathway by identifying the lowest energy S=1 LF state as an intermediate state with a lifetime of 39 ps for the light-induced high-spin to low-spin conversion on irradiation into the spin-allowed LF transition of the high-spin species in the NIR.

Ultrafast photoswitching in a copper-nitroxide-based molecular magnet.

Molecular compounds with photoswitchable magnetic properties have been intensively investigated over the last decades due to their prospective applications in nanoelectronics, sensing and magnetic data storage. The family of copper-nitroxide-based molecular magnets represents a new promising type of photoswitchable compounds. We report the first study of these appealing systems using femtosecond optical spectroscopy. We unveil the mechanism of ultrafast (<50 fs) spin state photoswitching and establish its principal differences compared to other photoswitchable magnets. On this basis, we propose potential advantages of copper-nitroxide-based molecular magnets for the future design of ultrafast magnetic materials.

Role of transcriptomic and genomic analyses in improving the comprehension of cefiderocol activity in Acinetobacter baumannii.

The mechanisms of action and resistance of cefiderocol (FDC) in Acinetobacter baumannii are still not fully elucidated, but iron transport systems have been evoked in its entry into the cell to reach the penicillin-binding proteins (PBPs). To capture the dynamics of gene expression related to FDC action in various conditions, we report on the genomic and transcriptomic features of seven A. baumannii strains with different FDC susceptibility, focusing on the variants in genes associated with ß-lactam resistance and the expression of the siderophore biosynthesis and transport systems acinetobactin and baumannoferrin. We also investigated the expression of the TonB energy transduction system (ETS) and siderophore receptors piuA and pirA. The four clinical samples belonged to the same clonal complex (CC2), and the two strains with the highest FDC MICs showed peculiar variants in PBP2 and ampC. Similarly, the two clinical strains with the lowest MICs shared variants in an outer membrane protein as well as ampC. Gene expression analyses highlighted the up-regulation of the acinetobactin and baumannoferrin genes in response to iron depletion and a down-regulation in the presence of high iron concentrations. In response to FDC, gene expression seemed strain-dependent, probably due to the different metabolic features of each strain. Overall, FDC activates the ETS, confirming the active import of the drug; baumannoferrin, more than acinetobactin, appeared stimulated by FDC in an iron-depleted medium. In conclusion, iron transport systems play a clear role in the FDC uptake, and their expression likely contributes to MIC variation together with ß-lactam resistance determinants.IMPORTANCEAcinetobacter baumannii poses a threat to healthcare due to its ability to give difficult-to-treat infections as a consequence of our shortage of antibiotic molecules active on this multidrug-resistant bacterium. Cefiderocol (FDC) represents one of the few drugs active on A. baumannii, and to preserve its activity, this study explored the transcriptomic and genomic features of seven strains with varying susceptibility to FDC. Transcriptomic analyses revealed the different effects of FDC on iron transport systems, promoting mainly baumannoferrin expression-thus more likely related to FDC entry-and the energy transduction systems. These findings suggest that not all iron transport systems are equally involved in FDC entry into A. baumannii cells. Finally, mutations in PBPs and ß-lactamases may contribute to the resistance onset. Overall, the study sheds light on the importance of iron availability and metabolic differences in FDC resistance, offering insights into understanding the evolution of resistance in A. baumannii strains.