Probiotic treatment causes sex-specific neuroprotection after traumatic brain injury in mice

Background

Recent studies have shed light on the potential role of gut dysbiosis in shaping traumatic brain injury (TBI) outcomes. Changes in the levels and types of Lactobacillus bacteria present might impact the immune system disturbances, neuroinflammatory responses, anxiety and depressive-like behaviors, and compromised neuroprotection mechanisms triggered by TBI.

Objective

This study aimed to investigate the effects of a daily pan-probiotic (PP) mixture in drinking water containing strains of Lactobacillus plantarum, L. reuteri, L. helveticus, L. fermentum, L. rhamnosus, L. gasseri, and L. casei, administered for either two or seven weeks before inducing TBI on both male and female mice.

Methods

Mice were subjected to controlled cortical impact (CCI) injury. Short-chain fatty acids (SCFAs) analysis was performed for metabolite measurements. The taxonomic profiles of murine fecal samples were evaluated using 16S rRNA V1-V3 sequencing analysis. Histological analyses were used to assess neuroinflammation and gut changes post-TBI, while behavioral tests were conducted to evaluate sensorimotor and cognitive functions.

Results

Our findings suggest that PP administration modulates the diversity and composition of the microbiome and increases the levels of SCFAs in a sex-dependent manner. We also observed a reduction of lesion volume, cell death, and microglial and macrophage activation after PP treatment following TBI in male mice. Furthermore, PP-treated mice show motor function improvements and decreases in anxiety and depressive-like behaviors.

Conclusion

Our findings suggest that PP administration can mitigate neuroinflammation and ameliorate motor and anxiety and depressive-like behavior deficits following TBI. These results underscore the potential of probiotic interventions as a viable therapeutic strategy to address TBI-induced impairments, emphasizing the need for gender-specific treatment approaches.

Sex-dependent improvement in traumatic brain injury outcomes after liposomal delivery of dexamethasone in mice

Traumatic Brain Injury (TBI) can have long-lasting physical, emotional, and cognitive consequences due to the neurodegeneration caused by its robust inflammatory response. Despite advances in rehabilitation care, effective neuroprotective treatments for TBI patients are lacking. Furthermore, current drug delivery methods for TBI treatment are inefficient in targeting inflamed brain areas. To address this issue, we have developed a liposomal nanocarrier (Lipo) encapsulating dexamethasone (Dex), an agonist for the glucocorticoid receptor utilized to alleviate inflammation and swelling in various conditions. In vitro studies show that Lipo-Dex were well tolerated in human and murine neural cells. Lipo-Dex showed significant suppression of inflammatory cytokines, IL-6 and TNF-α, release after induction of neural inflammation with lipopolysaccharide. Further, the Lipo-Dex were administered to young adult male and female C57BL/6 mice immediately after a controlled cortical impact injury. Our findings demonstrate that Lipo-Dex can selectively target the injured brain, thereby reducing lesion volume, cell death, astrogliosis, the release of proinflammatory cytokines, and microglial activation compared to Lipo-treated mice in a sex-dependent manner, showing a major impact only in male mice. This highlights the importance of considering sex as a crucial variable in developing and evaluating new nano-therapies for brain injury. These results suggest that Lipo-Dex administration may effectively treat acute TBI.

pH Method for Determination of Cholinesterase in Whole Blood: Collaborative Study

A collaborative study of an indirect method for determination of cholinesterase activity was conducted with cattle blood. Ten collaborators analyzed 8 samples of varying degrees of cholinesterase inhibition. The sample is diluted with a buffer, and the pH change that results from the hydrolysis of acetylcholine is monitored. Repeatability relative standard deviations (RSDr) ranged from 6.6 to 8.6%, and reproducibility relative standard deviations (RSDR) ranged from 10.7 to 17.3% for mean activities of 0.60-0.40 ΔpH/h. All samples that were completely inhibited were detected. The method was adopted first action by AOAC International for determination of cholinesterase activity in whole bovine blood.

RNA-Sequencing Analysis of Messenger RNA/MicroRNA in a Rabbit Aneurysm Model Identifies Pathways and Genes of Interest

BACKGROUND AND PURPOSE

Rabbit aneurysm models are used for the testing of embolization devices and elucidating the mechanisms of human intracranial aneurysm growth and healing. We used RNA-sequencing technology to identify genes relevant to induced rabbit aneurysm biology and to identify genes and pathways of potential clinical interest. This process included sequencing microRNAs, which are important regulatory noncoding RNAs.

MATERIALS AND METHODS

Elastase-induced saccular aneurysms were created at the origin of the right common carotid artery in 6 rabbits. Messenger RNA and microRNA were isolated from the aneurysm and from the control left common carotid artery at 12 weeks and processed by using RNA-sequencing technology. The results from RNA sequencing were analyzed by using the Ingenuity Pathway Analysis tool.

RESULTS

A total of 9396 genes were analyzed by using RNA sequencing, 648 (6.9%) of which were found to be significantly differentially expressed between the aneurysms and control tissues (P < .05; false-discovery rate, <0.01; fold change, >2 or <.5). Of these genes, 614 were mapped successfully, 143 were down-regulated, and 471 were up-regulated in the aneurysms as compared with controls. Using the same criteria for significance, 3 microRNAs were identified as down-regulated and 5 were identified as up-regulated. Pathway analysis associated these genes with inflammatory response, cellular migration, and coagulation, among other functions and pathologies.

CONCLUSIONS

RNA-sequencing analysis of rabbit aneurysms revealed differential regulation of some key pathways, including inflammation and antigen presentation. ANKRD1 and TACR1 were identified as genes of interest in the regulation of matrix metalloproteinases.

Coral calcifying fluid pH dictates response to ocean acidification

Ocean acidification driven by rising levels of CO₂ impairs calcification, threatening coral reef growth. Predicting how corals respond to CO₂ requires a better understanding of how calcification is controlled. Here we show how spatial variations in the pH of the internal calcifying fluid (pH_cf) in coral (Stylophora pistillata) colonies correlates with differential sensitivity of calcification to acidification. Coral apexes had the highest pH_cf and experienced the smallest changes in pH_cf in response to acidification. Lateral growth was associated with lower pH_cf and greater changes with acidification. Calcification showed a pattern similar to pH_cf, with lateral growth being more strongly affected by acidification than apical. Regulation of pH_cf is therefore spatially variable within a coral and critical to determining the sensitivity of calcification to ocean acidification.

X-ray linear dichroism dependence on ferroelectric polarization

X-ray absorption spectroscopy and photoemission electron microscopy are techniques commonly used to determine the magnetic properties of thin films, crystals, and heterostructures. Recently, these methods have been used in the study of magnetoelectrics and multiferroics. The analysis of such materials has been compromised by the presence of multiple order parameters and the lack of information on how to separate these coupled properties. In this work, we shed light on the manifestation of dichroism from ferroelectric polarization and atomic structure using photoemission electron microscopy and x-ray absorption spectroscopy. Linear dichroism arising from the ferroelectric order in the PbZr0:2Ti0:8O3 thin films was studied as a function of incident x-ray polarization and geometry to unambiguously determine the angular dependence of the ferroelectric contribution to the dichroism. These measurements allow us to examine the contribution of surface charges and ferroelectric polarization as potential mechanisms for linear dichroism. The x-ray linear dichroism from ferroelectric order revealed an angular dependence based on the angle between the ferroelectric polarization direction and the x-ray polarization axis, allowing a formula for linear dichroism in ferroelectric samples to be defined.

Cognitive effects of memantine in postmenopausal women at risk of dementia: a pilot study

BACKGROUND

To determine the effects of memantine on cognition in a normal population of postmenopausal women with putative risk factors for Alzheimer's disease (AD) using a built-in control for the genetic risk factor for AD (apoE-epsilon4 status).

METHODS

A prospective, open-label, 6-month pilot medication trial with memantine and follow-up after discontinuance conducted at the Center for Neuroscience in Women's Health, Stanford University School of Medicine. Neuropsychological data were collected on 22 community-dwelling postmenopausal women (11 apoE-epsilon4 carriers and 11 apoE-epsilon4 non-carriers) with at least one putative risk factor for AD.

RESULTS

ApoE-epsilon4 status was not a significant predictor of change in neuropsychological performance. Changes associated with memantine treatment for entire sample included significant declines in some variables associated with verbal learning and memory that improved upon medication withdrawal. A positive medication effect was noted with executive functions and possibly category fluency. Trend-level improvements were seen in motor dexterity of the non-dominant hand and maintained even after drug discontinuance.

CONCLUSIONS

Treatment with memantine appeared to have differential effects on cognitive performance in a population of women with putative risk factors for AD. ApoE-epsilon4 carrier status did not account for observed changes in cognition.

Telemedicine and telepresence for trauma and emergency care management

The use of telemedicine is long-standing, but only in recent years has it been applied to the specialities of trauma, emergency care, and surgery. Despite being relatively new, the concept of teletrauma, telepresence, and telesurgery is evolving and is being integrated into modern care of trauma and surgical patients. This paper will address the current applications of telemedicine and telepresence to trauma and emergency care as the new frontiers of telemedicine application. The University Medical Center and the Arizona Telemedicine Program (ATP) in Tucson, Arizona have two functional teletrauma and emergency telemedicine programs and one ad-hoc program, the mobile telemedicine program. The Southern Arizona Telemedicine and Telepresence (SATT) program is an inter-hospital telemedicine program, while the Tucson ER-link is a link between prehospital and emergency room system, and both are built upon a successful existing award winning ATP and the technical infrastructure of the city of Tucson. These two programs represent examples of integrated and collaborative community approaches to solving the lack of trauma and emergency care issue in the region. These networks will not only be used by trauma, but also by all other medical disciplines, and as such have become an example of innovation and dedication to trauma care. The first case of trauma managed over the telemedicine trauma program or "teletrauma" was that of an 18-month-old girl who was the only survival of a car crash with three fatalities. The success of this case and the pilot project of SATT that ensued led to the development of a regional teletrauma program serving close to 1.5 million people. The telepresence of the trauma surgeon, through teletrauma, has infused confidence among local doctors and communities and is being used to identify knowledge gaps of rural health care providers and the needs for instituting new outreach educational programs.

Oxygen consumption in unfertilized salmonid eggs: an indicator of egg quality?

A negative correlation between oxygen consumption and fertility was observed in both steelhead and chinook salmon eggs. However, this relationship was attributed to bacterial growth. Elimination of samples with bacterial growth resulted in no significant relationship between the rate of oxygen consumption (VO2) and fertility. VO2 of unfertilized eggs of both steelhead and chinook salmon was measured over a storage period of up to 24 days (d). Despite declines in fertility during storage, VO2 did not significantly change throughout storage. The average respiration rate for steelhead eggs was 3.4 nmol O2 per egg per h, and was 4.3 nmol O2 per egg per h for chinook salmon eggs. Treatment of chinook salmon eggs with uncouplers of mitochondrial respiration, 2,4-dinitrophenol (2,4-DNP) and carbonyl cyanide 4-trifluoro-methoxyphenylhydrazone (FCCP), resulted in an increase in VO2 to 12.9 and 11.5 nmol O2 per egg per h, respectively. Treatment with the putative uncoupler, clove oil, resulted in no change in VO2, while KCN, an inhibitor of oxidative phosphorylation, reduced oxygen consumption to zero. Copper caused an increase in oxygen consumption, even in the absence of eggs, suggesting a need for caution in interpreting changes in respiration rates as a result of metal exposure. Thus, unfertilized salmonid eggs demonstrated submaximal VO2, which was not correlated with fertility.

Carbon dioxide and pH affect sperm motility of white sturgeon(Acipenser transmontanus)

Maintenance of sperm at pH values less than approximately 7.5 inhibited the onset of motility when sperm were subsequently diluted with water; maintenance at pH values above approximately 8.2 was associated with maximal motility upon dilution with water. Within 5∼min of exposure to low pH buffer (pH 6.9),there was a 50% decline in sperm motility upon dilution with water suggesting that exposure to low pH interferes with motility within a time frame that may affect fertilization. In most instances, maintenance of sperm under CO2 at a pressure of 4-5 kPa almost completely blocked their capacity for motility. Furthermore, exposing semen to increasing partial pressures of CO2 up to about 1 kPa resulted in a marked decrease in semen pH. These observations are consistent with the findings that the buffering capacity of semen is particularly low at physiological pH, and that this low buffering capacity corresponds to the highest pH sensitivity of the capacity for sperm motility. The low seminal buffering capacity may represent a physiological adaptation in the control of sperm function. It may also represent a vulnerability to environmental hypercapnia or metabolic acidosis.

Sample preparation for the analysis of flavors and off-flavors in foods

Off-flavors in foods may originate from environmental pollutants, the growth of microorganisms, oxidation of lipids, or endogenous enzymatic decomposition in the foods. The chromatographic analysis of flavors and off-flavors in foods usually requires that the samples first be processed to remove as many interfering compounds as possible. For analysis of foods by gas chromatography (GC), sample preparation may include mincing, homogenation, centrifugation, distillation, simple solvent extraction, supercritical fluid extraction, pressurized-fluid extraction, microwave-assisted extraction, Soxhlet extraction, or methylation. For high-performance liquid chromatography of amines in fish, cheese, sausage and olive oil or aldehydes in fruit juice, sample preparation may include solvent extraction and derivatization. Headspace GC analysis of orange juice, fish, dehydrated potatoes, and milk requires almost no sample preparation. Purge-and-trap GC analysis of dairy products, seafoods, and garlic may require heating, microwave-mediated distillation, purging the sample with inert gases and trapping the analytes with Tenax or C18, thermal desorption, cryofocusing, or elution with ethyl acetate. Solid-phase microextraction GC analysis of spices, milk and fish can involve microwave-mediated distillation, and usually requires adsorption on poly(dimethyl)siloxane or electrodeposition on fibers followed by thermal desorption. For short-path thermal desorption GC analysis of spices, herbs, coffee, peanuts, candy, mushrooms, beverages, olive oil, honey, and milk, samples are placed in a glass-lined stainless steel thermal desorption tube, which is purged with helium and then heated gradually to desorb the volatiles for analysis. Few of the methods that are available for analysis of food flavors and off-flavors can be described simultaneously as cheap, easy and good.

Patterns of use and satisfaction with a university-based teleradiology system

The Radiology Department at the University of Arizona has been operating a teleradiology program for almost 2 years. The goal of this project was to characterize the types of cases reviewed, to assess radiologists' satisfaction with the program, and to examine case turnaround times. On average, about 50 teleradiology cases are interpreted each month. Computed tomography (CT) cases are the most common type of case, constituting 65% of the total case volume. Average turnaround time (to generate a "wet read" once a case is received) is about 1.3 hours. Image quality was rated as generally good to excellent, and the user interface as generally good. Radiologists' confidence in their diagnostic decisions is about the same as reading films in the clinical environment. The most common reason for not being able to read teleradiology images is poor image quality, followed by lack of clinical history and not enough images.

Analysis of fumonisin B1 in rodent feed by CE with fluorescence detection of the FMOC derivative

A fast, simple, and environmentally friendly method has been developed for the analysis of fumonisin B1 (FB1) in rodent feed using CE. FB1 is the major fumonisin metabolite produced by the fungus Fusarium moniliforme and has been implicated in human and animal diseases. FB1 was extracted from rodent feed with acetonitrile/water (50/50) (vol/vol) and cleaned up with a C18 Sep-Pak Vac cartridge (Waters Corp., Milford, MA, U.S.A.). FB1 was quantitated after elution from the column using capillary electrophoresis with a 25-mM sodium borate buffer (pH 9.0) containing 10% acetonitrile and fluorescence detection of the (9-fluorenylmethyl) chloroformate (FMOC) derivative. The minimum detectable amount in rodent feed was 0.5 pmm. Recovery values in spiked rodent feed averaged more than 87% over the 2-20 ppm range.

Fumonisin B1 analysis with capillary electrophoresis-electrospray ionization mass spectrometry

Fumonisin B1, a mycotoxin produced by a common fungal contaminant of corn, Fusarium moniliforme, was analyzed by capillary electrophoresis-electrospray ionization mass spectrometry. System performance was maximal with uncoated columns. System efficiencies of approximately 44,000 plates/m and reproducible analysis times of about 13 min were obtained. System efficiency with methyl-coated columns was approximately 24,000 plates/m. Reproducible analysis times of about 3.5 min were obtained with these columns. With uncoated columns, the concentration limit of detection was 156 ppb with a s/n ratio of approximately 10. The estimated injected mass at 156 ppb was 1.1 pg. Repeated injections of extracts containing constant fumonisin B1 concentrations showed that peak areas were slightly inconsistent, although generally similar to variations encountered with liquid chromatography-electrospray ionization mass spectrometry. The source of this inconsistency was traced to sample solubility, errors inherent in electrophoresis injections, and electrospray instability. Minimizing these problem areas will produce a technique with peak area reproducibilities comparable to liquid chromatography-electrospray ionization mass spectrometry, but with potentially greater resolving power.

Inhibition of 7,12-dimethylbenzanthracene-induced rat mammary tumor growth by 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds inhibit diverse estrogen-induced responses in the rodent uterus and human breast cancer cells. The effects of a single non-toxic dose of TCDD (10 micrograms/kg) on the development of mammary tumors was investigated in female Sprague-Dawley rats treated with an oral dose of 7,12-dimethylbenzanthracene (DMBA) (20 mg). In rats which developed mammary tumors, subsequent treatment with corn oil (vehicle) resulted in a 3.9-fold increase in mammary tumor volume after 21 days. In contrast, a second group of rats with mammary tumors were treated with a non-toxic dose of TCDD (10 micrograms/kg) and after 21 days, the mean tumor volumes decreased from 89.7 +/- 53 mm3 to 24.9 +/- 28.5 mm3. Moreover, these results demonstrate the antitumorigenic activity of TCDD in female Sprague-Dawley rats.

Determination of aflatoxins in food products by chromatography

Several chromatographic methods for the determination of aflatoxins in agricultural and food products are reviewed. During the past two decades, identification and determination of aflatoxins were done by thin-layer chromatography (TLC) because it was easy, fast and inexpensive. However, high-performance liquid chromatography (HPLC) using fluorescence detection is now the method of choice for determining aflatoxins and is also growing in popularity for their identification. The reasons for selecting HPLC over TLC can be summarized as the ability to analyze for a wide variety of compounds, including compounds that are easily degraded by heat, light or air, the ease of adaptation to confirmatory procedures, the potential for automation and the dramatic improvement in instrumentation, including the development of increasingly sensitive fluorescence and electrochemical detectors and short, high-resolution, reversed-phase columns.

Characterization of iodine derivatives of aflatoxin B1 and G1 by thermospray mass spectrometry

Thermospray mass spectrometry (TSMS) was used to identify the derivatives formed when iodine is reacted with aflatoxins B1 and G1 at approximately 70 degrees C to enhance fluorescence. It was found that stable derivatives were formed by addition of an iodine atom and a methoxy group across the double bond located on the furan ring of the aflatoxin B1 and G1 molecules. TSMS and TSMS/MS daughter spectra of the reaction products of aflatoxin B1 and G1 with iodine provide evidence of the addition of each moiety to produce the iodo-methoxy derivative. The addition of an iodine atom to one carbon and a methoxy group to the other carbon of the furan ring provided molecular weights of 470 and 486 for the products of aflatoxin B1 and G1, respectively.

Effect of electrocautery on wound healing in midline laparotomy incisions

The effect of electrocautery on midline fascial wound healing was studied in 108 Sprague-Dawley rats. Midline wound tensile strength was significantly reduced in fascia incised with the coagulation current compared with the cutting current or scalpel. In addition, tissue necrosis and inflammation as well as adhesion formation between the incision and abdominal viscera were more extensive in animals with incisions made using coagulation current. The results of the study indicate that the use of electrocautery coagulation current is associated with increased tissue damage and a significant reduction in the tensile strength of healing wounds. The contribution of electrocautery to wound complications in patients needs further evaluation.

Antibiotic irrigation and the formation of intraabdominal adhesions

The efficacy of antibiotic peritoneal lavage in the prevention of postoperative infection is controversial. The role of intraperitoneally administered cefazolin and tetracycline in the formation of adhesions was studied in the rodent model. Thirty-two rats were divided into 3 groups. Group 1 underwent midline laparotomy with instillation of 10 ml of normal saline solution. Group 2 and Group 3 underwent the same procedure with instillation of 0.2 percent saline solutions of cefazolin or tetracycline, respectively. Animals were sacrificed after 2 weeks. Intraabdominal adhesions were graded and samples of parietal peritoneum were processed for histologic data. Group 2 and Group 3 had significantly higher adhesion scores compared with Group 1 (p less than 0.001). Histologic appearance of both antibiotic-irrigated groups showed mesothelial thickening with presence of fibroblasts and collagen. Cefazolin and tetracycline irrigation of the abdominal cavity contributes to the formation of peritoneal adhesions in the rat model.

Development and validation of in vitro induction assays for toxic halogenated aromatic mixtures: a review

Halogenated aromatic industrial compounds, typified by the polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) have been identified as residues in almost every component of the global ecosystem. Risk assessment of the complex mixtures of halogenated aromatics found in environmental samples is complicated by analytical problems and the lack of toxicological information on individual compounds and mixtures. Research in our laboratory has focused on the development and vadidation of the in vitro aryl hydrocarbon hydroxylase (AHH) induction assay in rat hepatoma H-4-II E cells in culture for quantitating individual toxic halogenated aryl hydrocarbons and their mixtures. For several PCB, PCDD, PCDF congeners, their mixed bromo/chloro analogs and reconstituted mixtures there was an excellent linear correlation between their -log ED50 values for AHH induction in rat hepatoma cells and their -log ED50 values for in vivo hepatic microsomal AHH induction, inhibition of body weight gain and thymic atrophy in the rat. It has also been shown for selected compounds that there was a good correlation between their in vitro AHH induction potencies and their effects in guinea pigs (AHH induction, inhibition of body weight gain) and mice (immunotoxicity). This assay system has been utilized to quantitative the "2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents" present in extracts from diverse sources including fly ash from a municipal incinerator and pyrolyzed brominated flame retardants which contain a complex mixture of halogenated dibenzo-p-dioxins and dibenzofurans.

Biologic and toxic effects of polychlorinated dibenzo-p-dioxin and dibenzofuran congeners in the guinea pig. Quantitative structure-activity relationships

The dose-response effects of 2,3,7,8-tetrachorodibenzo-p-dioxin, 1,3,7,8-tetrachlorodibenzo-p-dioxin, 1,2,4,7,8-pentachlorodibenzo-p-dioxin, 2,3,4,7,8-, 1,2,3,7,9-, and 2,3,4,7,9-pentachlorodibenzofuran on body weight loss and hepatic microsomal aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) induction were determined in the immature male guinea pig. The ED50 values for each compound were measured for the three in vivo responses. The quantitative structure-activity relationships clearly illustrated that the most toxic congeners were substituted in the lateral 2, 3, 7 and 8 positions, and removal of a lateral chlorine group substantially reduced the potency of the resulting compound. The most toxic congener in this series was 2,3,7,8-tetrachlorodibenzo-p-dioxin in which the in vivo ED50 values for AHH and EROD induction and body weight loss were 2.8 X 10(-10), 9.3 X 10(-11) and 5.6 X 10(-9) mol/kg. The structure-activity relationships observed in this study were comparable to those previously reported in rats and rat hepatoma H-4-II E cells in culture. Moreover, there was an excellent linear correlation between in vivo -log ED50 values for body weight loss, AHH and EROD induction and the corresponding in vitro -log EC50 data for AHH induction in rat hepatoma cells [S. Safe, Chemosphere 16, 791 (1987)].