Mouse Models of Sepsis.

Human sepsis is a complex disease that manifests with a diverse range of phenotypes and inherent variability among individuals, making it hard to develop a comprehensive animal model. Despite this difficulty, numerous models have been developed that capture many key aspects of human sepsis. The robustness of these models is vital for conducting pre-clinical studies to test and develop potential therapeutics. In this article, we describe four different models of murine sepsis that can be used to address different scientific questions relevant to the pathology and immune response during and after a septic event. Basic Protocol 1 details a non-synchronous cecal ligation and puncture (CLP) model of sepsis, where mice are subjected to polymicrobial exposure through surgery at different time points within 2 weeks. This variation in sepsis onset establishes each mouse at a different state of inflammation and cytokine levels that mimics the variability observed in humans when they present in the clinic. This model is ideal for studying the long-term impact of sepsis on the host. Basic Protocol 2 is also a type of polymicrobial sepsis, where injection of a specific amount of cecal slurry from a donor mouse into the peritoneum of recipient mice establishes immediate inflammation and sepsis without any need for surgery. Basic Protocol 3 describes infecting mice with a defined gram-positive or -negative bacterial strain to model a subset of sepsis observed in humans infected with a single pathogen. Basic Protocol 4 describes administering LPS to induce sterile endotoxemia. This form of sepsis is observed in humans exposed to bacterial toxins from the environment. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Non-synchronous cecal ligation and puncture Basic Protocol 2: Cecal slurry model of murine sepsis Basic Protocol 3: Monomicrobial model of murine sepsis Basic Protocol 4: LPS model of murine sepsis.

Regenerating murine CD8+ lung tissue resident memory T cells after targeted radiation exposure.

Radiation exposure occurs during medical procedures, nuclear accidents, or spaceflight, making effective medical countermeasures a public health priority. Naïve T cells are highly sensitive to radiation-induced depletion, although their numbers recover with time. Circulating memory CD8+ T cells are also depleted by radiation; however, their numbers do not recover. Critically, the impact of radiation exposure on tissue-resident memory T cells (TRM) remains unknown. Here, we found that sublethal thorax-targeted radiation resulted in the rapid and prolonged numerical decline of influenza A virus (IAV)-specific lung TRM in mice, but no decline in antigen-matched circulating memory T cells. Prolonged loss of lung TRM was associated with decreased heterosubtypic immunity. Importantly, boosting with IAV-epitope expressing pathogens that replicate in the lungs or peripheral tissues or with a peripherally administered mRNA vaccine regenerated lung TRM that was derived largely from circulating memory CD8+ T cells. Designing effective vaccination strategies to regenerate TRM will be important in combating the immunological effects of radiation exposure.

Adverse outcomes and an immunosuppressed endotype in septic patients with reduced IFN-γ ELISpot.

BACKGROUNDSepsis remains a major clinical challenge for which successful treatment requires greater precision in identifying patients at increased risk of adverse outcomes requiring different therapeutic approaches. Predicting clinical outcomes and immunological endotyping of septic patients generally relies on using blood protein or mRNA biomarkers, or static cell phenotyping. Here, we sought to determine whether functional immune responsiveness would yield improved precision.METHODSAn ex vivo whole-blood enzyme-linked immunosorbent spot (ELISpot) assay for cellular production of interferon γ (IFN-γ) was evaluated in 107 septic and 68 nonseptic patients from 5 academic health centers using blood samples collected on days 1, 4, and 7 following ICU admission.RESULTSCompared with 46 healthy participants, unstimulated and stimulated whole-blood IFN-γ expression was either increased or unchanged, respectively, in septic and nonseptic ICU patients. However, in septic patients who did not survive 180 days, stimulated whole-blood IFN-γ expression was significantly reduced on ICU days 1, 4, and 7 (all P < 0.05), due to both significant reductions in total number of IFN-γ-producing cells and amount of IFN-γ produced per cell (all P < 0.05). Importantly, IFN-γ total expression on days 1 and 4 after admission could discriminate 180-day mortality better than absolute lymphocyte count (ALC), IL-6, and procalcitonin. Septic patients with low IFN-γ expression were older and had lower ALCs and higher soluble PD-L1 and IL-10 concentrations, consistent with an immunosuppressed endotype.CONCLUSIONSA whole-blood IFN-γ ELISpot assay can both identify septic patients at increased risk of late mortality and identify immunosuppressed septic patients.TRIAL REGISTRYN/A.FUNDINGThis prospective, observational, multicenter clinical study was directly supported by National Institute of General Medical Sciences grant R01 GM-139046, including a supplement (R01 GM-139046-03S1) from 2022 to 2024.

Adverse Long-Term Outcomes and an Immune Suppressed Endotype in Sepsis Patients with Reduced Interferon-γELISpot: A Multicenter, Prospective Observational Study.

BACKGROUND: Sepsis remains a major clinical challenge for which successful treatment requires greater precision in identifying patients at increased risk of adverse outcomes requiring different therapeutic approaches. Predicting clinical outcomes and immunological endotyping of septic patients has generally relied on using blood protein or mRNA biomarkers, or static cell phenotyping. Here, we sought to determine whether functional immune responsiveness would yield improved precision. METHODS: An ex vivo whole blood enzyme-linked immunosorbent (ELISpot) assay for cellular production of interferon-γ (IFN-γ) was evaluated in 107 septic and 68 non-septic patients from five academic health centers using blood samples collected on days 1, 4 and 7 following ICU admission. RESULTS: Compared with 46 healthy subjects, unstimulated and stimulated whole blood IFNγ expression were either increased or unchanged, respectively, in septic and nonseptic ICU patients. However, in septic patients who did not survive 180 days, stimulated whole blood IFNγ expression was significantly reduced on ICU days 1, 4 and 7 (all p<0.05), due to both significant reductions in total number of IFNγ producing cells and amount of IFNγ produced per cell (all p<0.05). Importantly, IFNγ total expression on day 1 and 4 after admission could discriminate 180-day mortality better than absolute lymphocyte count (ALC), IL-6 and procalcitonin. Septic patients with low IFNγ expression were older and had lower ALC and higher sPD-L1 and IL-10 concentrations, consistent with an immune suppressed endotype. CONCLUSIONS: A whole blood IFNγ ELISpot assay can both identify septic patients at increased risk of late mortality, and identify immune-suppressed, sepsis patients.

Serum level of vitamin A in febrile children with and without seizure: A comparative study.

Objective: The role of vitamins and antioxidants in the febrile seizure (FS) has recently become of interest. The role of Vitamin A in seizure is remained controversial. It may suppress or provoke the seizure. In present study, the serum vitamin A level in febrile patients was compared with febrile seizure children for the first time. Method: In a cross-sectional study, eighty children aged 6-60 months including 40 febrile children and 40 children with FS were included. Blood samples were obtained, and the serum level of vitamin A and other blood parameters were measured. Results: Patients were similar in demographic characteristics (p = 0.06 for age and p = 0.41 for sex). The serum vitamin A level was 0.19 (0.12, 0.25) and 0.22 (0.17, 0.29) milligram per liter (mg/L) in febrile and FS group respectively (p = 0.33). In children aged less than 24 months the serum vitamin A level in FS and febrile group was 0.22 ± 0.07 and 0.24 ± 0.12 mg/L respectively (p = 0.56). In children aged more than 24 months the serum vitamin A level in FS group was higher significantly in comparison with febrile group (0.25 ± 0.11 and 0.16 ± 0.07 mg/L respectively, p = 0.01). Conclusion: Serum vitamin A level was not different in febrile children with and without seizure. Surprisingly in children aged more than 24 months, the serum level of vitamin A was higher in FS group than in the febrile children. More studies are needed to confirm the present observation.

Sublethal whole-body irradiation induces permanent loss and dysfunction in pathogen-specific circulating memory CD8 T cell populations.

The increasing use of nuclear energy sources inevitably raises the risk of accidental or deliberate radiation exposure and associated immune dysfunction. However, the extent to which radiation exposure impacts memory CD8 T cells, potent mediators of immunity to recurring intracellular infections and malignancies, remains understudied. Using P14 CD8 T cell chimeric mice (P14 chimeras) with an lymphocytic choriomeningitis virus (LCMV) infection model, we observed that sublethal (5Gy) whole-body irradiation (WBI) induced a rapid decline in the number of naive (TN) and P14 circulating memory CD8 T cells (TCIRCM), with the former being more susceptible to radiation-induced numeric loss. While TN cell numbers rapidly recovered, as previously described, the number of P14 TCIRCM cells remained low at least 9 mo after radiation exposure. Additionally, the remaining P14 TCIRCM in irradiated hosts exhibited an inefficient transition to a central memory (CD62L+) phenotype compared to nonirradiated P14 chimeras. WBI also resulted in long-lasting T cell intrinsic deficits in memory CD8 T cells, including diminished cytokine and chemokine production along with impaired secondary expansion upon cognate Ag reencounter. Irradiated P14 chimeras displayed significantly higher bacterial burden after challenge with Listeria monocytogenes expressing the LCMV GP33-41 epitope relative to nonirradiated controls, likely due to radiation-induced numerical and functional impairments. Taken together, our findings suggest that sublethal radiation exposure caused a long-term numerical, impaired differentiation, and functional dysregulation in preexisting TCIRCM, rendering previously protected hosts susceptible to reinfection.

Sepsis-induced changes in differentiation, maintenance, and function of memory CD8 T cell subsets.

Formation of long-lasting memory lymphocytes is one of the foundational characteristics of adaptive immunity and the basis of many vaccination strategies. Following the rapid expansion and contraction of effector CD8 T cells, the surviving antigen (Ag)-specific cells give rise to the memory CD8 T cells that persist for a long time and are phenotypically and functionally distinct from their naïve counterparts. Significant heterogeneity exists within the memory CD8 T cell pool, as different subsets display distinct tissue localization preferences, cytotoxic ability, and proliferative capacity, but all memory CD8 T cells are equipped to mount an enhanced immune response upon Ag re-encounter. Memory CD8 T cells demonstrate numerical stability under homeostatic conditions, but sepsis causes a significant decline in the number of memory CD8 T cells and diminishes their Ag-dependent and -independent functions. Sepsis also rewires the transcriptional profile of memory CD8 T cells, which profoundly impacts memory CD8 T cell differentiation and, ultimately, the protective capacity of memory CD8 T cells upon subsequent stimulation. This review delves into different aspects of memory CD8 T cell subsets as well as the immediate and long-term impact of sepsis on memory CD8 T cell biology.

Carotid Intima-media Thickness in Hemodialysis Patients and Related Biochemical and Clinical Factors.

INTRODUCTION: Cardiovascular complications are the most frequent cause of death in chronic kidney disease that happens due to both general and uremic risk factors. Recently, the medical literature has declared the carotid artery intima-media thickness to be an indicator for predicting cardiovascular diseases. METHODS: This paper is an attempt to introduce an analytical cross-sectional study of 128 hemodialysis patients. The researchers collected the data by reviewing medical records, interviewing the patients, chemical analysis of the patient's serum and carotid artery Doppler ultrasound, and providing the relevant questionnaire. We performed descriptive statistics, bivariate correlation, and general linear model (GLM) analysis. And, the significance level of hypothesis tests was .05. RESULTS: Seventy-three patients (57%) were male, and 55 (43%) were female. The mean and standard deviation of the age was 58.66 ± 15.54 years. Nearly 42% of patients affected by diabetes, 95.3% were hypertensive and 28.1% had a history of cardiovascular disease. In the bivariate analysis, age, serum albumin, serum magnesium, hypertension, and history of cardiovascular disease showed a statistically significant relationship with carotid intima-media thickness (CIMT). In GLM, we observed a statistically significant relationship between CIMT, age and magnesium. CONCLUSION: Increased CIMT is observed in a considerable percentage of hemodialysis patients. Age and serum magnesium concentration demonstrate a statistically significant association with CIMT. We recommend more precise long-term longitudinal follow-up studies to investigate the relationship between biochemical risk factors and CIMT. Therefore, multivariate analysis is necessary to assess the simultaneous effects of independent variables and manage influences of confounding factors. We also recommend developing a practical guideline for periodic determination of CIMT in hemodialysis patients to implement convenient preventive or therapeutic measures.  DOI: 10.52547/ijkd.7303.

Evaluation the feasibility of using clinoptilolite as a gravel pack in water wells for removal of lead from contaminated groundwater.

The ability of clinoptilolite zeolite as a filter in water wells to remove lead from polluted groundwater was tested in batch and fixed-bed column experiments. XRF, XRD, SEM, and BET were used to characterize the zeolite. Because of the pH variation in groundwater, batch experiments were performed at pH = 6, 7, and 8, with the highest removal efficiency (84.2%) at pH = 6 and 298 K within 90 min. The Freundlich model accurately predicted metal ion adsorption behavior and indicated a multilayer adsorption of Pb(II) molecules on the inhomogeneous surface of clinoptilolite. The best-fitting kinetic model for clinoptilolite is the pseudo-second order equation, highlighting that the rate of adsorption is dependent on absorbent capacity. Next, the effect of flow rate, bed depth, and grain size of clinoptilolite on lead removal was investigated in column experiments at an initial concentration of 450 mg pb/L. The highest removal efficiency was achieved in column experiments with a flow rate of 1 mL/min, a bed height of 10 cm, and a grain size of 0.6 to 0.8 mm. Breakthrough curves were predicted by the Thomas and Yoon-Nelson models, with excellent agreement with the corresponding experimental data. This research will be used to develop a new in situ remedial approach for removing lead from polluted groundwater.

A Comparison Between Serum Selenium Level in Febrile Children with or Without Seizure.

The role of trace elements in febrile seizure (FS) was considered recently. The present study was performed evaluating the serum level of selenium in febrile children aged 6-60 months with and without seizure. A cross-sectional study was performed in Mashhad University of Medical Sciences, Mashhad, Iran. Sixty patients aged 6-60 months including 30 children with FS and 30 febrile children without seizure were included. Blood sample was taken, and the serum level of selenium was measured. Data was analyzed using SPSS software. Sixteen patients in FS group (53.3%) and 10 patients in febrile group (33.3%) were males with an average age of 25.21 ± 15.91 and 26.47 ± 17.61 months, respectively. There was no significant difference between groups in age and sex (p = 0.77 and p = 0.19, respectively). The serum level of selenium was 87.34 ± 8.23 and 89.63 ± 9.83 µg/L in FS and febrile groups, respectively. Difference was not significant (p = 0.33). In children aged less than 1 year, the serum level of selenium in FS and febrile group was 83.32 ± 6.2 µg/L and 82.55 ± 8.32 µg/L, respectively. Difference was not significant (p = 0.87). In children aged more than 1 year, the serum level of selenium in FS significantly was lower compared to febrile group (87.96 ± 8.42 µg/L and 93.17 ± 8.66 µg/L, respectively, p = 0.04). The serum level of selenium was lower in children aged more than 1 year with febrile seizure compared to febrile ones.

Serum Level of Vitamin D and Febrile Seizure? A Clinical Study.

OBJECTIVE: To evaluate the serum level of vitamin D in children aged six to 60 months with febrile seizure and febrile children without the seizure. MATERIALS & METHODS: Febrile children aged six to 60 months with or without seizure were studied. Demographic characteristics, serum level of vitamin D, and other laboratory findings were recorded. RESULTS: Among the 104 children, 51 patients had fever without a seizure and 53 patients had a febrile seizure. The mean subjects' age was significantly more in the febrile seizure group compared to the without seizure group (16.26 ± 11.87 versus 26.36 ± 14.11 months, p = 0.001). The mean serum level of vitamin D in the with and without seizure groups was 41.92 ± 22.42 and 48.41 ± 15.25 microgram per deciliter, respectively (p = 0.08). There was no significant correlation between serum level of vitamin D and seizure occurrence (p = 0.07). The mean serum sodium and potassium levels, and platelet count were significantly lower in the febrile seizure group compared to the without seizure group (p < 0.05). There were no significant differences between the two groups regarding hemoglobin, blood sugar, creatinine, blood urea nitrogen, calcium, alkaline phosphatase levels, and white blood cell count (p > 0.05). CONCLUSION: The serum level of vitamin D in febrile children with or without seizure was normal. The serum level of vitamin D was lower in patients with the seizure but not statistically significant. More clinical studies are needed to evaluate the relationship between febrile seizure and the serum level of vitamin D.

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids.

Rational design of disordered molecular aggregates and solids for optoelectronic applications relies on our ability to predict the properties of such materials using theoretical and computational methods. However, large molecular systems where disorder is too significant to be considered in the perturbative limit cannot be described using either first principles quantum chemistry or band theory. Multiscale modeling is a promising approach to understanding and optimizing the optoelectronic properties of such systems. It uses first-principles quantum chemical methods to calculate the properties of individual molecules, then constructs model Hamiltonians of molecular aggregates or bulk materials based on these calculations. In this paper, we present a protocol for constructing a tight-binding Hamiltonian that represents the excited states of a molecular material in the basis of Frenckel excitons: electron-hole pairs that are localized on individual molecules that make up the material. The Hamiltonian parametrization proposed here accounts for excitonic couplings between molecules, as well as for electrostatic polarization of the electron density on a molecule by the charge distribution on surrounding molecules. Such model Hamiltonians can be used to calculate optical absorption spectra and other optoelectronic properties of molecular aggregates and solids.

Gastroenteritis Related Seizure with or without Fever: Comparison Clinical Features and Serum Sodium Level.

OBJECTIVE: This study investigated the clinical characteristics and serum sodium level in children with gastroenteritis related seizure with or without fever. MATERIALS & METHODS: This clinical study was performed in Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran from 2007 to 2014. Overall, 165 patients aged 6-60 months with gastroenteritis related seizure were studied. Demographic, seizure and gastroenteritis characteristics and laboratory findings were recorded. RESULTS: Among the 165 children 47.3% were female. Vomiting was 2.7±2.6 and 3.9±1.9 times in febrile and afebrile group. Duration of diarrhea was 1.8±1.8 days and 2.1±1.3 days in febrile and afebrile groups (p=0.014). 36% in febrile group and 6.4% in afebrile group experienced seizure within the first 24 h of gastroenteritis (P<0.001). Seizure in 99.1% in febrile and 93.6% in afebrile group was generalized (P>0.05). Seizure was more than 5 min in 51.4% in febrile and 57.4% in afebrile groups (P>0.05). Drowsiness after seizure was seen in 72.9% and 60% in febrile and afebrile group respectively (P>0.05). The serum level of sodium was 137.6±3.98 mEq/L and 138.5±3.78 mEq/L in febrile and afebrile groups (P>0.05). 26.3% in febrile group and 8.5% in afebrile group had hyponatremia (P=0.012). There was no difference in seizure duration between hyponatremic patients and others (P>0.05). CONCLUSION: Type, duration of seizure and drowsiness after seizure had not any difference in febrile and afebrile cases. Vomiting and duration of diarrhea before admission was lower in febrile group. Seizure within the first 24 h of gastroenteritis was higher in febrile group. Mild hyponatremia in febrile group was higher than afebrile group. No difference in duration of seizure was detected between hyponatremic patients and others.

Metal-Ligand Multiple Bonding in Thorium Phosphorus and Thorium Arsenic Complexes.

The complexes (C5 Me5 )2 Th(EHTipp)2 , (E=P or As; Tipp=2,4,6-triisopropylphenyl), provide a ligand framework that results in facile access to rare Th-E multiple bonds. The reaction of (C5 Me5 )2 Th(EHTipp)2 with KN(SiMe3 )2 , proceeds cleanly to the desired bridging phosphinidiide or arsinidiide complex, [{(C5 Me5 )2 Th(µ2 -ETipp)(µ2 -EHTipp)}K]2 under ambient conditions. In the absence of a chelating agent, the potassium cation of one monomeric unit interacts with the aryl ring of a second monomer to form a bridged dimer. In the presence of 2,2,2-cryptand, the terminal phosphinidene complex, [(C5 Me5 )2 Th=PTipp(PHTipp)][K(2,2,2-cryptand)] is isolated. Using X-ray crystallographic analysis, we have determined these complexes display the shortest Th-P and Th-As bond lengths reported.