Modular air-liquid interface aerosol exposure system (MALIES) to study toxicity of nanoparticle aerosols in 3D-cultured A549 cells in vitro.

We present a novel lung aerosol exposure system named MALIES (modular air-liquid interface exposure system), which allows three-dimensional cultivation of lung epithelial cells in alveolar-like scaffolds (MatriGrids®) and exposure to nanoparticle aerosols. MALIES consists of multiple modular units for aerosol generation, and can be rapidly assembled and commissioned. The MALIES system was proven for its ability to reliably produce a dose-dependent toxicity in A549 cells using CuSO4 aerosol. Cytotoxic effects of BaSO4- and TiO2-nanoparticles were investigated using MALIES with the human lung tumor cell line A549 cultured at the air-liquid interface. Experiments with concentrations of up to 5.93 × 105 (BaSO4) and 1.49 × 106 (TiO2) particles/cm3, resulting in deposited masses of up to 26.6 and 74.0 µg/cm2 were performed using two identical aerosol exposure systems in two different laboratories. LDH, resazurin reduction and total glutathione were measured. A549 cells grown on MatriGrids® form a ZO-1- and E-Cadherin-positive epithelial barrier and produce mucin and surfactant protein. BaSO4-NP in a deposited mass of up to 26.6 µg/cm2 resulted in mild, reversible damage (~ 10% decrease in viability) to lung epithelium 24 h after exposure. TiO2-NP in a deposited mass of up to 74.0 µg/cm2 did not induce any cytotoxicity in A549 cells 24 h and 72 h after exposure, with the exception of a 1.7 fold increase in the low exposure group in laboratory 1. These results are consistent with previous studies showing no significant damage to lung epithelium by short-term treatment with low concentrations of nanoscale BaSO4 and TiO2 in in vitro experiments.

Autoinfection as a cause of postpartum subdural empyema due to Mycoplasma hominis.

Mycoplasma hominis is a commensal of the genitourinary tract, which is infrequently associated with urogenital infections. Extra-urogenital infections due to M. hominis are rare. Here, we report an unusual case of M. hominis subdural empyema in a woman occurring shortly after delivery. The patient presented with symptoms suggestive of bacterial meningitis. Spinal imaging revealed a subdural empyema that required neurosurgical intervention. Cultures from intraoperatively obtained biopsies identified M. hominis as the causative pathogen. The patient was treated with oral moxifloxacin for 4 weeks resulting in the resolution of the spinal lesion. The subdural empyema was presumably caused by a contaminated epidural blood patch performed with the patient's own blood during an episode of transient M. hominis bacteremia after delivery. The blood patch was indicated for the treatment of cerebrospinal fluid leakage, which had occurred after epidural anesthesia. Our findings highlight the significance of transient M. hominis bacteremia after delivery and implicate that M. hominis should be considered as a causative agent of extra-genitourinary tract infections particularly during the postpartum period or after genitourinary manipulation.

Costs and resource utilization patterns in surgical site infections: a pre-COVID-19 perspective from France, Germany, Spain, and the UK.

BACKGROUND: Surgical site infections (SSIs), mainly caused by Staphylococcus aureus, pose a significant economic burden in Europe, leading to increased hospitalization duration, mortality, and treatment costs, particularly with drug-resistant strains such as meticillin-resistant S. aureus. AIM: To conduct a case-control study on the economic impact of S. aureus SSI in adult surgical patients across high-volume centres in France, Germany, Spain, and the UK, aiming to assess the overall and procedure-specific burden across Europe. METHODS: The SALT study is a multinational, retrospective cohort study with a nested case-control analysis focused on S. aureus SSI in Europe. The study included participants from France, Germany, Italy, Spain, and the UK who underwent invasive surgery in 2016 and employed a micro-costing approach to evaluate health economic factors, matching S. aureus SSI cases with controls. FINDINGS: In 2016, among 178,904 surgical patients in five European countries, 764 developed S. aureus SSI. Matching 744 cases to controls, the study revealed that S. aureus SSI cases incurred higher immediate hospitalization costs (€8,810), compared to controls (€6,032). Additionally, S. aureus SSI cases exhibited increased costs for readmissions within the first year post surgery (€7,961.6 versus €5,298.6), with significant differences observed. Factors associated with increased surgery-related costs included the cost of hospitalization immediately after surgery, first intensive care unit (ICU) admission within 12 months, and hospital readmission within 12 months, as identified through multivariable analysis. CONCLUSION: The higher rates of hospitalization, ICU admissions, and readmissions among S. aureus SSI cases highlight the severity of these infections and their impact on healthcare costs, emphasizing the potential benefits of evidence-based infection control measures and improved patient care to mitigate the economic burden.

Biomimetic reconstruction of the hematopoietic stem cell niche for in vitro amplification of human hematopoietic stem cells.

Hematopoietic stem cell transplantation is successfully applied since the late 1950s; however, its efficacy still needs to be increased. A promising strategy is to transplant high numbers of pluripotent hematopoietic stem cells (HSCs). Therefore, an improved ex vivo culture system that supports proliferation and maintains HSC pluripotency would override possible limitations in cell numbers gained from donors. To model the natural HSC niche in vitro, we optimized the HSC medium composition with a panel of cytokines and valproic acid and used an artificial 3D bone marrow-like scaffold made of polydimethylsiloxane (PDMS). This 3D scaffold offered a suitable platform to amplify human HSCs in vitro and, simultaneously, to support their viability, multipotency and ability for self-renewal. Silicon oxide-covering of PDMS structures further improved amplification of CD34+ cells, although the conservation of naïve HSCs was better on non-covered 3D PDMS. Finally, we found that HSC cultivated on non-covered 3D PDMS generated most pluripotent colonies within colony forming unit assays. In conclusion, by combining biological and biotechnological approaches, we optimized in vitro HSCs culture conditions, resulting in improved amplification, multipotency maintenance and vitality of HSCs.

A population of murine gammadelta T cells that recognize an inducible MHC class Ib molecule.

Although gammadelta T cells are implicated in regulating immune responses, gammadelta T cell-ligand pairs that could mediate such regulatory functions have not been identified. Here, the expression of the major histocompatibility complex (MHC) class Ib T22 and the closely related T10 molecules is shown to be activation-induced, and they confer specificity to about 0.4% of the gammadelta T cells in normal mice. Thus, the increased expression of T22 and/or T10 might trigger immunoregulatory gammadelta T cells during immune responses. Furthermore, the fast on-rates and slow off-rates that characterize this receptor/ligand interaction would compensate for the low ligand stability and suggest a high threshold for gammadelta T cell activation.

Treatment strategies of space-occupying intradural metastases of the cauda equina of nonneurogenic origin.

BACKGROUND: Compressive intradural metastases of the cauda equina are a rare site of metastatic spread in systemic cancer. So far, only few reports have been published with conflicting statements concerning a surgical versus nonsurgical approach. METHOD: Five patients with symptomatic space-occupying intradural metastases of the cauda equina were analyzed retrospectively, focusing on the influence of surgical intervention on pain relief, neurological outcome and thus the patients' quality of life. FINDINGS: At the time of diagnosis, all patients were in an advanced metastatic state. Surgical resection was the primary treatment in four patients and radiotherapy in one. Despite infiltration of the cauda rootlets, gross total tumour resection could be achieved in two of the four patients treated surgically. Functional outcome was beneficial in these patients with marked and immediate relief of pain and improvement of motor function even following incomplete tumour resection. CONCLUSIONS: Surgical treatment of compressive intradural metastases of the cauda equina seems to be feasible with low operative risk and with the potential benefit of an immediate relief of pain and improvement in motor function and thus an increase in quality of life.

Nutritional and socioeconomic factors in relation to prostate cancer mortality: a cross-national study.

BACKGROUND: Large international variations in rates of prostate cancer incidence and mortality suggest that environmental factors have a strong influence on the development of this disease. The purpose of this study was to identify predictive variables for prostate cancer mortality in data from 59 countries. METHODS: Data on prostate cancer mortality, food consumption, tobacco use, socioeconomic factors, reproductive factors, and health indicators were obtained from United Nations sources. Linear regression models were fit to these data. The influence of each variable fit in the regression models was assessed by multiplying the regression coefficient b by the 75th (X75) and 25th (X25) percentile values of the variable. The difference, bX75 - bX25, is the estimated effect of the variable across its interquartile range on mortality rates measured as deaths per 100000 males aged 45-74 years. Reported P values are two-sided. RESULTS: Prostate cancer mortality was inversely associated with estimated consumption of cereals (bX75 - bX25 = -7.31 deaths; P = .001), nuts and oilseeds (bX75 - bX25 = -1.72 deaths; P = .003), and fish (bX75 - bX25 = -1.47 deaths; P = .001). In the 42 countries for which we had appropriate data, soy products were found to be significantly protective (P = .0001), with an effect size per kilocalorie at least four times as large as that of any other dietary factor. Besides variables related to diet, we observed an association between prostate cancer mortality rates and a composite of other health-related, sanitation, and economic variables (P = .003). CONCLUSIONS: The specific food-related results from this study are consistent with previous information and support the current dietary guidelines and hypothesis that grains, cereals, and nuts are protective against prostate cancer. The findings also provide a rationale for future study of soy products in prostate cancer prevention trials.

The putative tumor suppressor gene FHIT at 3p14.2 is rarely affected by loss of heterozygosity in primary human brain tumors.

To elucidate the role of the recently identified FHIT gene, located at 3p14.2 in human brain tumor carcinogenesis, a total of 259 tumors were analyzed for loss of heterozygosity (LOH) at microsatellite loci D3S1313, D3S1234, D3S1300, and D3S1481. In primary brain tumors, LOH was detected at a frequency of 8.4% (n = 214). Low-grade gliomas exhibited insignificantly lower LOH rates in comparison to high-grade gliomas (5.3%, n = 19, versus 11.1%, n = 90). Notably, no allelic loss was observed in 12 recurrent glioblastomas analyzed in comparison to their corresponding primary tumor lesions and in two astrocytomas with progression to higher grades of malignancy. Our data indicate that allelic loss of the FHIT gene is neither a critical event in carcinogenesis of primary brain tumors nor tumor grade-associated in astrocytic tumors. In contrast, observed LOH rate for brain metastases was as high as 54.5% (n = 45), in accordance with data thus far accumulated from analyses of corresponding primary tumors.

Loss of heterozygosity accumulation in primary breast carcinomas and additionally in corresponding distant metastases is associated with poor outcome.

The occurrence of distant metastases is the most feared manifestation of breast cancer, often occurring years after the primary surgery and associated with poor survival. The dominant metastatic clone is characterized by an accumulation of genetic alterations, but it is not actually known at what stage of the metastatic cascade these alterations have occurred. We investigated allelic losses during breast cancer progression in a series of 17 primary breast carcinomas and 22 corresponding brain, liver, lung, and bone metastases (mean metastasis-free interval, 31 months) by analyzing 19 microsatellite markers on seven breast cancer- or metastasis-related chromosomal regions and correlated the incidence of combined loss of heterozygosity (LOH) with metastasis-free and postmetastatic survival. We found that, in comparison with the corresponding primary tumor, additional LOH events are frequently found in metastases and that the incidence of combined LOH in the primary tumor, plus the occurrence of additional LOH events in the distant metastases, correlated significantly with decreased postmetastatic survival. Combined LOH of the three breast cancer-related chromosomal regions alone or in combination with allelic loss at the p53 gene region seems to have a specific influence on the aggressive behavior of metastases. We hypothesize that the occurrence of additional LOH events is either involved in termination of dormancy of micrometastatic tumor cells at distant organ sites or acquired during further progression of metastases.

The identification of a chlorinated MDMA.

The abuse of the designer amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA) is increasing throughout the world. They have become popular drugs at all night techno dance parties, and their detection is an important issue. The objective of the presented study was to identify an unknown compound detected by thin-layer chromatography (TLC) in the urine of an illicit drug abuser. The compound was isolated by TLC and analyzed by gas chromatography-mass spectrometry (GC-MS) in electron ionization (EI) and positive ion chemical ionization (PICI) mode to elucidate its chemical structure. Based on EI-MS and PICI-MS mass spectral data, the unknown compound was indicated to be a structure similar to MDMA, substituted by a single chlorine atom-a chlorinated MDMA (Cl-MDMA). To confirm the Cl-MDMA structure, the unknown compound was silylated, trifluoroacetylated, acetylated, heptafluorobutyrylated, and analyzed by GC-MS. The position of the chlorine atom cannot be assigned exactly from the mass spectral data presented here; however, we believe that the unknown compound could be 6-Cl-MDMA.

Presentation of insulin and insulin A chain peptides to mouse T cells: involvement of cysteine residues.

The requirements for insulin presentation and recognition by A alpha b A beta b- and A alpha b A beta k-restricted mouse T cells were studied using a variety of derivatives of the insulin A chain. It was found that A chain peptides with irreversibly blocked Cys residues are non-stimulatory for the T cells. This suggests that at least one of the Cys residues is essential for recognition. On the other hand, all A chain peptides containing Cys residues modified in a way reversible by reaction with thiols are stimulatory yet differ in antigenic potency. All these A chain derivatives including a 14 amino acid fragment require uptake by antigen presenting cells (APC) for efficient presentation. Differences in stimulatory potency between the A chain peptides derived from the same insulin appear to be mainly due to the efficiency of uptake and/or processing by APC. Based on these findings we propose that processing in the case of insulin and its A chain derivatives involves the reductive deblocking of Cys residues or the rearrangement of disulfide bonds apart from a possible proteolytic cleavage. The same may apply to other proteins if Cys residues in the presented peptides are important for the interaction with Ia or the T cell receptor.

Antioxidant intakes and smoking status: data from the continuing survey of food intakes by individuals 1994-1996.

BACKGROUND: Cigarette smoking is a major risk factor for several chronic oxidative diseases that can be ameliorated by antioxidants. OBJECTIVES: This study identified the typical dietary intakes and the major food group contributors of the antioxidants beta-carotene, vitamin C, and vitamin E by smoking status. DESIGN: The 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII) provided the current sample (n = 6749), who were categorized as non- (n = 3231), former (n = 1684), and current (n = 1834) smokers. In the CSFII, individuals' food intakes were estimated with two 24-h dietary recalls. Data were analyzed by using a chi-square test with a simultaneous Fisher's z test, analysis of variance with Scheffe's test, multivariate analysis of covariance, and analysis of covariance with Bonferroni adjustment for multiple comparisons. RESULTS: The sample consisted of 3707 men and 3042 women. Current smokers tended to be younger with less education and lower incomes than nonsmokers and former smokers. The average body mass index (in kg/m(2)) of current smokers was 25.8, the lowest of the 3 groups. Current smokers had the lowest dietary antioxidant intake. Fatty foods such as luncheon meats, condiments and salad dressings, and ground beef contributed more to the antioxidant intakes of current smokers than to those of the other 2 groups, whereas fruit and vegetables contributed less. Current smokers consumed the fewest numbers of servings of all nutrient-bearing groups in the food guide pyramid, except the meat group. CONCLUSION: Future interventions should target the clustering of cigarette smoking and other unhealthy lifestyle habits, eg, an imprudent diet.

Cigarette use during adolescence: effects on nutritional status.

Despite numerous anti-tobacco campaigns, smoking among adolescents continues to be a predominant public health issue. This report details the interrelationships between adolescence, smoking, and nutrition and health. Current data indicate that most smokers become nicotine-dependent as adolescents, which places them at risk for chronic diseases associated with continuous oxidative damage. Additionally, nicotine has antidepressant and hypermetabolic effects, which may be of particular importance during adolescence because nicotine use leads to increased dependence on tobacco, contributes to difficulty in smoking cessation, and promotes weight gain following smoking cessation.

Breastfeeding-related onset, flare, and relapse of rheumatoid arthritis.

The beneficial effects of pregnancy on rheumatoid arthritis have been known for decades. Only recently, however, have lactation and prolactin been targeted as predictors of onset, flare, or relapse of arthritis. Among genetically susceptible women, breastfeeding is associated with an increased risk of rheumatoid arthritis, particularly after the first pregnancy. Dietary interventions may reduce symptoms experienced by arthritic women.

Use of scanning electron microscopy to investigate the prophylactic efficacy of rifampin-impregnated CSF shunt catheters.

Infection continues to be one of the major complications of cerebrospinal fluid (CSF) shunting procedures, and is caused mainly by skin-derived bacteria. Production of an extracellular biofilm plays an important role in the pathogenesis of shunt-associated infections by protecting bacteria from immune mechanisms and antibiotics. So far, removal of the original shunt and implantation of a new shunting device has been the only successful treatment for most patients. As an alternative strategy to prevent CSF infections, a rifampin-impregnated silicone catheter was designed to provide high initial and long-lasting (>60 days) release of bactericidal drug. To investigate the pathophysiological mechanism of its function, this new device was investigated both in vitro and in a rodent model of CSF infection by scanning electron microscopy (SEM) and bacterial culture. Staphylococcus epidermidis (10(8) cfu/ml) and S. aureus (10(4) cfu/ml) served as test strains. SEM demonstrated that, in contrast to the unloaded catheters, initial bacterial adherence on the catheter surface could be reduced to a few single cells, which did not show visible signs of proliferation. Bacterial cultures obtained simultaneously were all sterile, showing that adherent bacteria were killed immediately by the rifampin released from the catheter. Although rifampin incorporation into silicone polymers was not able to prevent initial bacterial adhesion completely, subsequent colonisation could be prevented.

Loss of BRCA2 correlates with reduced long-term survival of sporadic breast cancer patients.

BACKGROUND: The present study was undertaken to analyze the prognostic value of loss of heterozygosity (LOH) at 13q12-13, 17q21 and 17p13, harboring BRCA2, BRCA1 and p53 to predict the clinical course of sporadic breast cancer patients. MATERIALS AND METHODS: LOH analysis was performed by PCR amplification of genomic DNA using nine microsatellite markers. Fifty-three sporadic breast cancer patients were followed clinically for a median of 55 months. Disease-free and overall survival was documented as the endpoint for statistical evaluation. RESULTS: Patients presenting with LOH in their tumor samples at at least one of the loci examined were found to have a reduced overall survival time compared to those retaining heterozygosity (61% versus 48%). Focusing on the three target regions, patients with LOH at the BRCA2 locus died earlier compared to patients retaining heterozygosity (69% versus 50%) and, in addition, BRCA2 LOH-positive patients showed a shorter metastasis-free interval (30 versus 37 months). In a multivariate analysis, LOH at the 13q12-13 locus was found to be a significant predictor for reduced long-term survival (risk ratio 2.33, 95% C.I., 1.0-5.3; p<0.05) and earlier metastases manifestation (risk ratio 2.32, 95% C.I., 1.0-5.3, p<0.05). CONCLUSION: Allelic loss at the BRCA2 locus may be of use as a negative predictor for metastases-free and overall survival.

Comparisons of dietary intake and sources of fat in low- and high-fat diets of 18- to 24-year-olds.

OBJECTIVE: To determine the sources of fat in the diets of 18- to 24-year-olds and to identify the food group choices of those consuming 30% of energy or less from fat. DESIGN: This study compared the fat intake, nutrient intake, and food group choices of young men and women consuming 30% or less or more than 30% of energy from fat. SUBJECTS: The 1989-1991 Continuing Survey of Food Intakes by individuals (CSFII) provided the study sample of 1,062 (436 men and 626 women) 18- to 24-year-olds residing in the 48 coterminous states who completed one 24-hour food recall and two 1-day food records. MAIN OUTCOME MEASURES: Dietary fat, vitamin, mineral, and food group intakes were determined by analysis of the 24-hour food recalls and the 1-day food records. STATISTICAL ANALYSIS PERFORMED: Tests were used to detect differences in nutrient and food group intakes between the two groups for both men and women. RESULTS: More than 75% of the sample consumed more than 30% of energy from fat. The men and women who consumed low-fat diets did so by choosing more low-fat dairy products, fruits, and grains. Men who consumed low-fat diets consumed significantly more alcohol than other men; women who consumed low-fat diets showed a similar trend although the difference was not statistically significant. Although men and women who consumed a high-fat diet did consume significantly greater amounts of fat and cholesterol, they also fared better in vitamin and mineral intake. CONCLUSIONS: A minority of young adults consumed 30% or less of energy from fat. Compared with those who consumed more than 30% of energy from fat, men consumed significantly greater mean amounts of vitamin C and folate, and women consumed significantly greater mean amounts of vitamin A and folate. Young adults who consumed more than 30% of energy from fat exceeded current recommendations for dietary fat intake; however, the men were less likely to be at risk for calcium deficiency and the women were less likely to be at risk for vitamin E and zinc deficiencies. Because excess dietary fat and alcohol can lead to chronic disease, dietitians should continue to educate people about the relationship between nutrition and health.

The 'age+5' rule: comparisons of dietary fiber intake among 4- to 10-year-old children.

OBJECTIVE: To determine children's sources of dietary fiber and to identify the food group choices made by those who met the "age+5" rule, which recommends that children daily consume an amount of fiber that is equal to their age plus an additional 5 g fiber. DESIGN: This study used 24-hour dietary recalls and 1-day food records to assess the nutrient intake and food group choices of children who did and did not meet the recommendations of the age+5 rule. SUBJECTS: The 1989-1991 US Department of Agriculture Continuing Survey of Food Intakes by Individuals provided the study sample of 603 children between the ages of 4 and 6 years and 782 children between the ages of 7 and 10 years. STATISTICAL ANALYSES: Differences in nutrient and food group intakes between age categories were determined by t tests. RESULTS: Only 45% of 4- to 6-year-olds and 32% of 7- to 10-year-olds consumed adequate fiber to meet the age+5 rule. Those who met the age+5 rule did so by consuming significantly more high- and low-fiber breads and cereals, fruits, vegetables, legumes, nuts, and seeds. Children with low fiber intakes had significantly higher energy-adjusted intakes of fat and cholesterol, whereas those who met the age+5 rule had significantly higher energy-adjusted intakes of dietary fiber, vitamins A and E, folate, magnesium, and iron. APPLICATIONS: The majority of the children had low intakes of dietary fiber, suggesting that they are at risk for future chronic disease. Parents and school foodservice personnel should strive to offer fiber-rich foods to children so their acceptance and consumption of them will be increased.

Using standardized patients to train and evaluate dietetics students.

Faced with a dwindling number of clinical sites for training dietetics students, we incorporated a standardized patient scenario of a 17-year-old pregnant woman into a nutrition counseling course. A young woman was hired to be the patient and was trained extensively. Each student signed up for a 20-minute block of time to assess her and provide nutrition instruction, after which the standardized patient and course instructor provided individualized feedback to each student. Students then completed a brief questionnaire related to the standardized patient session. Overall, student response to the standardized patient session was positive, and students believed standardized patients should be included formally in undergraduate training. The students noted that the standardized patient session allowed them to be trained and evaluated objectively. Because of their ease in building rapport with the standardized patient, students reported that they were able to provide more in-depth education. They also appreciated the immediate and detailed performance review provided by the standardized patient and the instructor. We conclude that standardized patient sessions provide a great service to dietetics students, and plans to develop another standardized patient scenario that students can follow up throughout the continuum of care are underway.

Nutrient Intake Report: a coordination of patient dietary assessment between physicians and registered dietitians.

The Nutrient Intake Report (NIR) is based on a 7-day dietary recall questionnaire used previously in research for dietary assessment and adapted for clinical use. Used to provide information and counseling as part of total patient care, the NIR acts as a cornerstone for dietary education and interaction between physician, registered dietitian, and patient. The NIR is ordered by physicians or registered dietitians, scanned and assessed by a registered dietitian, and incorporated into the laboratory section of the medical record. It documents the patient's dietary intake in the context of his or her diagnosis and general health status. The NIR also opens a dialogue between physicians and registered dietitians. Incorporation of the NIR into the medical record makes the work of the registered dietitian available to other health practitioners, which is welcome in an era when licensing and reimbursement are contingent on systematic documentation of dietary assessment and its role in patient care.