Fetal bradycardia in open versus fetoscopic prenatal repair of spina bifida.

OBJECTIVE: To compare the occurrence of fetal bradycardia in open versus fetoscopic fetal spina bifida surgery. METHODS: This is a single-institution retrospective cohort study of patients undergoing open (n = 25) or fetoscopic (n = 26) spina bifida repair between 2017 and 2022. From October 2017 to June 2020, spina bifida repairs were performed via an open classical hysterotomy, and from November 2020 to June 2022 fetoscopic repairs were performed following transition to this technique. Fetal heart rate (FHR) in beats per minute (bpm) was recorded via echocardiography every 15 min during the procedure. Cohort characteristics, fetal bradycardia and maternal physiologic parameters were compared between the groups. RESULTS: Fetuses undergoing an open repair more frequently developed bradycardia defined as <110 bpm (32% vs. 3.8%, p = 0.008), and a trend was observed for FHR decreases more than 25 bpm from baseline (20% vs. 3.8%, p = 0.073). Profound bradycardia less than 80 bpm was rare, occurring in only three operations (two in open, one in fetoscopic repair) with two fetuses (one in each group) requiring emergency cesarean delivery. CONCLUSION: When compared to open fetal surgery, fetal bradycardia occurred less frequently in fetoscopic surgery despite a significantly greater anesthetic exposure and the use of the intraamniotic carbon dioxide insufflation.

Needle Fetal Thoracoscopy: A Technique to Assist with Ultrasound-Guided Placement of Challenging Thoracoamniotic Shunts.

INTRODUCTION: Fetal thoracoamniotic shunts are common lifesaving interventions but frequently require replacement. Needle fetal thoracoscopy is a technique that uses standard thoracoamniotic shunt introducer sheaths to permit direct visualization and even instrument manipulation during shunt deployment to facilitate optimal positioning and primary shunt function in the most challenging cases. CASE PRESENTATION: In this study, 5 patients who underwent needle fetal thoracoscopy-assisted thoracoamniotic shunt placement were reviewed. Three patients with large, macrocystic congenital pulmonary airway malformations (CPAMs) with evidence of worsening mediastinal shift and/or hydrops and 2 patients with large chylothorax with fetal hydrops were treated. Four cases had previous shunts that failed due to poor sonographic visualization during initial placement, cyst septations, shunt obstruction, or dislodgment. Needle fetal thoracoscopy was used to disrupt cyst walls and septations, clear hematoma, and confirm the optimal initial position of the shunt. In this series, 1 severe CPAM patient with a short cervix developed preterm labor postoperatively resulting in neonatal demise. The remaining 4 patients experienced resolution of hydrops and progressed to successful delivery with excellent neonatal outcomes. CONCLUSION: Needle fetal thoracoscopy is a procedure that may be selectively deployed in challenging thoracoamniotic shunt cases impacted by recurrent failure, poor sonographic windows, and challenging fetal positioning.

Acculturative stress, collectivistic coping, and drinking in a predominantly Latino college sample.

OBJECTIVES: The present study explored the association of acculturative stress with alcohol consumption and problems, and whether these associations varied by collectivistic coping style in a predominantly Latino college sample. METHOD: Participants were 192 (58.9% female; Mage = 23.4 years, SD = 6.6; 89.6% Hispanic or Latino) undergraduate students from the University of Texas at El Paso that participated in a survey that assessed their acculturative stress, collectivistic coping styles, alcohol use, and associated problems. Hierarchical regression analyses were used to determine the potential moderating effect of collectivistic coping styles on the relationship between acculturative stress and drinking variables. RESULTS: Hierarchical regression analyses revealed a significant two-way interaction between acculturative stress and seeking social support in predicting monthly drinking frequency, heavy drinking frequency, peak number of drinks, and alcohol problems. They also revealed a significant two-way interaction between acculturative stress and forbearance in predicting heavy drinking frequency and peak number of drinks. The associations between acculturative stress and each of the outcomes were positive at low levels of collectivistic coping style. However, these relationships became increasingly negative as the collectivistic coping style increased. CONCLUSIONS: The present study extends the literature on collectivistic coping by exploring the protective effects of collectivistic coping styles against drinking among Latino college students. Based on current findings, it appears that among Latino students, seeking social support may serve as a protective factor against the effects of acculturative stress on alcohol use and problems and that forbearance may serve as a protective factor against the effects of acculturative stress on alcohol use. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Control of astrocytic Ca2+ signaling by nitric oxide-dependent S-nitrosylation of Ca2+ homeostasis modulator 1 channels.

BACKGROUND: Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthetizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. RESULTS: Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptor-dependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. CONCLUSIONS: Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.

Digital dermatitis-associated Treponema species detection and quantification in migratory tundra caribou (Rangifer tarandus).

Treponema spp. are associated with infectious lameness in livestock and wild ruminants. While extensive research has been conducted on cattle, investigations in wild ruminants are scarce. Hoof disease is common in caribou populations (Rangifer tarandus), but investigations are limited due to the remoteness of the Arctic. Our study aimed to assess the presence of Treponema spp. associated with bovine digital dermatitis in caribou. DNA was extracted from coronary band tissues from forty-eight caribou without visible hoof lesions and analyzed using two PCR methods (qPCR and nPCR). Treponema spp. were detected in low copy numbers/mg of tissue (3.6 to 6.6 × 101). T. phagedenis was the most prevalent and abundant species in 58% of samples by qPCR, followed by T. medium (44%), and T. pedis (10%). The qPCR and nPCR agreement ranged between 65% and 75% (Cohen's kappa 0.22-0.51). Sanger sequencing of thirteen nPCR products confirmed that treponemes in caribou are remarkably similar to those found in domestic ruminants and wild elk. Our study highlights the colonization of treponemes in healthy hooves of a wild ruminant in the Arctic, where there is no presence of livestock, and expands knowledge on the host range and distribution of treponemes. These findings also emphasize the need for further research into the multifactorial nature of treponema-associated hoof diseases and the putative role of treponemes in infectious lameness affecting caribou.

Exploring Pathways to Caregiver Health: The Roles of Caregiver Burden, Familism, and Ethnicity.

OBJECTIVES: This study examines the associations of ethnicity, caregiver burden, familism, and physical and mental health among Mexican Americans (MAs) and non-Hispanic Whites (NHWs). METHODS: We recruited adults 65+ years with possible cognitive impairment (using the Montreal Cognitive Assessment score<26), and their caregivers living in Nueces County, Texas. We used weighted path analysis to test effects of ethnicity, familism, and caregiver burden on caregiver's mental and physical health. RESULTS: 516 caregivers and care-receivers participated. MA caregivers were younger, more likely female, and less educated compared to NHWs. Increased caregiver burden was associated with worse mental (B = -0.53; p < .001) and physical health (B = -0.15; p = .002). Familism was associated with lower burden (B = -0.14; p = .001). MA caregivers had stronger familism scores (B = 0.49; p < .001). DISCUSSION: Increased burden is associated with worse caregiver mental and physical health. MA caregivers had stronger familism resulting in better health. Findings can contribute to early identification, intervention, and coordination of services to help reduce caregiver burden.

A Community-Based Study of Dementia in Mexican American and Non-Hispanic White Individuals.

BACKGROUND: Little information is available on the prevalence of cognitive impairment in Mexican American persons. OBJECTIVE: To determine the prevalence of mild cognitive impairment (MCI) and dementia in those 65 years and older among Mexican American and non-Hispanic white individuals in a community. METHODS: This was a population-based cohort study in Nueces County, Texas, USA. Participants were recruited using a random housing sample. The Harmonized Cognitive Assessment (HCAP) participant and informant protocol was performed after Montreal Cognitive Assessment (MoCA) screening. An algorithm was used to sort participants into diagnostic categories: no cognitive impairment, MCI, or dementia. Logistic regression determined the association of ethnicity with MCI and dementia controlling for age, gender, and education. RESULTS: 1,901 participants completed the MoCA and 547 the HCAP. Mexican Americans were younger and had less educational attainment than non-Hispanic whites. Overall, dementia prevalence was 11.6% (95% CI 9.2-14.0) and MCI prevalence was 21.2% (95% CI 17.5-24.8). After adjusting for age, gender, and education level, there was no significant ethnic difference in the odds of dementia or MCI. Those with ≤11 compared with ≥16 years of education had much higher dementia [OR = 4.9 (95% CI 2.2-11.1)] and MCI risk [OR = 3.5 (95% CI 1.6-7.5)]. CONCLUSIONS: Dementia and MCI prevalence were high in both Mexican American and non-Hispanic white populations. Mexican American persons had double the odds of mild cognitive impairment and this was attenuated when age and educational attainment were considered. Educational attainment was a potent predictor of cognitive impairment.

Ex-Utero Intrapartum Treatment-to-Airway for Obstructing Fetal Neck Masses: A Singular Methodology for Monochorionic and Dichorionic Twin Pregnancies.

Fetal airway obstruction in one twin of a diamniotic pregnancy presents unique challenges. Very few cases of ex-utero-intrapartum-treatment (EXIT) procedures for twin pregnancy have been reported and only in dichorionic pregnancies. We report a singular methodology for EXIT-to-airway procedures in two pregnancies involving monochorionic and dichorionic twins. Two cases of EXIT-to-airway in twin pregnancies were performed in 2018 and 2019 at a regional fetal treatment center. Case 1 involved a giant cervical teratoma in a monochorionic-diamniotic twin pregnancy with preterm labor at 29 weeks. Case 2 involved a dichorionic-diamniotic pregnancy with a large cervical lymphatic malformation with preterm labor at 36 weeks. In each case, the polyhydramnios caused the affected twin's amniotic sac to be the presenting sac for the surgical approach. Bronchoscopy and successful intubation was completed after 22 and 10 minutes of uteroplacental bypass, respectively. The bystander twins were delivered second without intubation and resuscitated without perinatal distress. EXIT-to-airway appears to be a reasonable option for twins including monochorionic pregnancies, via delivery of the affected twin first followed by delivery of the bystander twin. Thoughtful preparation and counseling by an experienced multidisciplinary team permits an EXIT-to-airway approach for twin pregnancies even in an emergent setting.

A Community-Based Study of Cognitive Impairment Caregiving Outcomes Pre- and During the COVID-19 Pandemic.

The impact of the COVID-19 pandemic on informal caregiving was examined in a Mexican American (MA) and Non-Hispanic White (NHW) population-based cohort. 395 participants age > 65 years were recruited via door-to-door and phone recruitment as part of the Brain Attack Surveillance in Corpus Christi-Cognitive (BASIC-C) project. Both recipients and caregivers answered questions regarding the recipient's health and the COVID-19 pandemic. 15% of caregivers saw their caregiving recipient less than before the pandemic and 18% saw their recipient more than before. 55% of caregivers reported a slight to severe impact of the pandemic on their caregiving, and 45% reported no impact. For most caregivers, their caregiving role did not change markedly during the pandemic. MA and NHW caregivers had similar survey responses.

Genome sequences of six cluster CT and two cluster DJ bacteriophages that infect Gordonia rubripertincta.

We report the genome sequences of eight bacteriophages isolated using Gordonia rubripertincta NRRL B-16540-SEA. Based on gene content similarity to phages in the Actinobacteriophage database, six of the phages are assigned to phage cluster CT while two are assigned to cluster DJ.

Antithrombin concentrates may benefit cardiopulmonary bypass patients with suspected heparin resistance: A retrospective analysis of real-world data.

Background: Heparin resistance is a common complication of surgical patients requiring anticoagulation, such as those undergoing cardiopulmonary bypass (CPB). Treatments to address heparin resistance include supplementation of antithrombin (AT) or fresh frozen plasma (FFP). This retrospective database analysis compared key outcomes in suspected heparin-resistant patients undergoing CPB treated with AT or FFP. Methods: De-identified United States electronic health records (Cerner Health Facts®) were queried. International Classification of Diseases (ICD-9/10) codes were used to determine CPB procedures and FFP administration. AT administration was identified using medication data, while a combination of lab and medication data examining activated clotting times detected heparin resistance in FFP patients. Adult inpatients (≥18 years old) seen between 2001 and 2018 were included. Differences in mortality, intensive care unit (ICU) length of stay (LOS), and hospital-free days (using a 30-day post-discharge period) were assessed with univariate models as well as adjusted logistic regression models controlling for patient characteristics and Charlson Comorbidity Index (CCI) scores. Results: Of the 502 patients identified, 247 received AT and 255 received FFP. The FFP cohort was associated with a higher CCI compared to the AT cohort (3.3 ± 2.4 vs. 2.3 ± 2.0, P < .001). The AT cohort was associated with a 71% (Odds Ratio [OR]: 0.29, 95% Confidence Interval [CI]: P = .003) and 66% (OR: 0.34, 95% CI: P = .01) reduction in mortality when compared to FFP using univariate and adjusted logistic regression models, respectively. Similarly, use of AT also showed a 22% shorter ICU LOS (P = .02) and 10% more hospital-free days in the 30 days following discharge (P = .004) according to the univariate models, though statistical significance was absent within adjusted models in both ICU LOS (P = .08) and hospital-free days (P = .53). Conclusions: Compared to FFP, AT use suggests a reduction in the odds of mortality in suspected heparin-resistant patients undergoing CPB, though larger prospective studies are necessary to elucidate potential differences in hospital-free days or ICU LOS across treatment modalities.

Opening of Cx43-formed hemichannels mediates the Ca2+ signaling associated with endothelial cell migration.

Endothelial cell migration is a key process in angiogenesis. Progress of endothelial cell migration is orchestrated by coordinated generation of Ca2+ signals through a mechanism organized in caveolar microdomains. Connexins (Cx) play a central role in coordination of endothelial cell function, directly by cell-to-cell communication via gap junction and, indirectly, by the release of autocrine/paracrine signals through Cx-formed hemichannels. However, Cx hemichannels are also permeable to Ca2+ and Cx43 can be associated with caveolin-1, a structural protein of caveolae. We proposed that endothelial cell migration relies on Cx43 hemichannel opening. Here we show a novel mechanism of Ca2+ signaling in endothelial cell migration. The Ca2+ signaling that mediates endothelial cell migration and the subsequent tubular structure formation depended on Cx43 hemichannel opening and is associated with the translocation of Cx43 with caveolae to the rear part of the cells. These findings indicate that Cx43 hemichannels play a central role in endothelial cell migration and provide new therapeutic targets for the control of deregulated angiogenesis in pathological conditions such as cancer.

Driving predictors in a cohort of cognitively impaired Mexican American and non-Hispanic White individuals.

BACKGROUND: Individuals with Alzheimer's disease and Alzheimer's disease-related dementias may lose the ability to drive safely as their disease progresses. Little is known about driving prevalence in older Latinx and non-Hispanic White (NHW) individuals. We investigated the prevalence of driving status among individuals with cognitive impairment in a population-based cohort. METHODS: This was a cross-sectional analysis of the cohort BASIC-Cognitive study in a community of Mexican American (MA) and NHW individuals in South Texas. Participants scored ≤25 on the Montreal Cognitive Assessment (MoCA), indicating a likelihood of cognitive impairment. Current driving status was assessed by the Harmonized Cognitive Assessment Protocol informant interview. Logistic regression was used to assess driving versus non-driving adjusted for pre-specified covariates. Chi-square and Mann-Whitney U tests were used to compare NHW and MA differences in driving outcomes from the American Academy of Neurology (AAN) questions for evaluating driving risk in dementia. RESULTS: There were 635 participants, 77.0 mean age, 62.4% women, and 17.3 mean MoCA. Of these, 360 (61.4%) were current drivers with 250 of 411 (60.8%) MA participants driving, and 121 of 190 (63.70%) NHW participants driving (p = 0.50). In fully adjusted models age, sex, cognitive impairment, language preference, and Activities of Daily Living scores were significant predictors for the likelihood of driving (p < 0.0001). Severity of cognitive impairment was inversely associated with odds of driving, but this relationship was not found in those preferring Spanish language for interviews. Around one-third of all caregivers had concerns about their care-recipient driving. There were no significant differences in MA and NHW driving habits and outcomes from the AAN questionnaire. CONCLUSIONS: The majority of participants with cognitive impairment were currently driving. This is a cause for concern for many caregivers. There were no significant ethnic driving differences. Associations with current driving in cognitively impaired persons require further research.

Connexin 40-Mediated Regulation of Systemic Circulation and Arterial Blood Pressure.

Vascular system is a complex network in which different cell types and vascular segments must work in concert to regulate blood flow distribution and arterial blood pressure. Although paracrine/autocrine signaling is involved in the regulation of vasomotor tone, direct intercellular communication via gap junctions plays a central role in the control and coordination of vascular function in the microvascular network. Gap junctions are made up by connexin (Cx) proteins, and among the four Cxs expressed in the cardiovascular system (Cx37, Cx40, Cx43, and Cx45), Cx40 has emerged as a critical signaling pathway in the vessel wall. This Cx is predominantly found in the endothelium, but it is involved in the development of the cardiovascular system and in the coordination of endothelial and smooth muscle cell function along the length of the vessels. In addition, Cx40 participates in the control of vasomotor tone through the transmission of electrical signals from the endothelium to the underlying smooth muscle and in the regulation of arterial blood pressure by renin-angiotensin system in afferent arterioles. In this review, we discuss the participation of Cx40-formed channels in the development of cardiovascular system, control and coordination of vascular function, and regulation of arterial blood pressure.

Psychosocial and Psychodynamic Considerations Informing Factitious Disorder.

Factitious disorder is a condition in which patients deceitfully present themselves as injured or ill in the absence of obvious external reward. It is difficult to diagnose and treat, and little rigorous evidence exists in the literature. While larger studies have revealed some clinical and sociodemographic patterns, there is a lack of consensus on psychosocial factors and mechanisms contributing to factitious disorder. This in turn has led to conflicting recommendations on management. In this article, we review major psychopathological theories of factitious disorder, including the role of early trauma and subsequent development of interpersonal dysfunction, as well as maladaptive gratification obtained from assuming the sick role. Common themes of interpersonal disruptions in this patient population include a pathologic need for attention and care, as well as aggression and desire for dominance. In addition to psychodynamic and psychosocial etiologic models of factitious disorder, we also review associated treatment approaches. Finally, we offer clinical implications, including countertransference considerations, as well as directions for future research.

Differential Apoptotic Effects of Bee Product Mixtures on Normal and Cancer Hepatic Cells.

Most effective anticancer drugs normally generate considerable cytotoxicity in normal cells; therefore, the preferential activation of apoptosis in cancer cells and the reduction of toxicity in normal cells is a great challenge in cancer research. Natural products with selective anticancer properties used as complementary medicine can help to achieve this goal. The aim of the present study was to analyze the effect of the addition of bee products [propolis (PR) or royal jelly (RJ) or propolis and royal jelly (PR+RJ), 2-10%] to thyme (TH) and chestnut honeys (CH) on the differential anticancer properties, mainly the cytotoxic and pro-apoptotic effects, in normal and cancer hepatic cells. The cytotoxic effects of samples were analyzed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay (0-250 mg/mL) and the effects on apoptosis were analyzed using cell cycle analysis, TdT-dUTP terminal nick-end labeling (TUNEL) assay, DR5 (Death Receptor 5) and BAX (BCL-2-Associated X) activation, and caspases 8, 9, and 3 activities. Both honey samples alone and honey mixtures had no or very little apoptotic effect on normal cells. Antioxidant honey mixtures enhanced the apoptotic capacity of the corresponding honey alone via both extrinsic and intrinsic pathways. Of all the samples, chestnut honey enriched with 10% royal jelly and 10% propolis (sample 14, CH+10RJ+10PR) showed the highest apoptotic effect on tumor liver cells. The enrichment of monofloral honey with bee products could be used together with conventional anticancer treatments as a dietary supplement without side effects. On the other hand, it could be included in the diet as a natural sweetener with high added value.

Combined Modelling of Triply Paired Electronic States of HO2 + ion with 3 Symmetry using Coupled Eigen Model.

The multi state triply paired coupled adiabatic electronic states of X 3 A ' ' ${X\,^3 A^{\prime \prime } }$ 1 3 A ' ' ${1\,^3 A^{\prime \prime } }$ , 2 3 A ' ' ${2\,^3 A^{\prime \prime } }$ symmetries for the title ion have been modelled using the triply paired coupled eigen valued functions with the principal aim of getting a set of well optimized triply paired coupled functions, capable of explaining all the microscopic topograhical features present in the chosen coupled electronic states. The high quality size truncated dynamically correlated points at the limit of complete basis set (CBS) were utilized for this purpose. The proposed model function are presented in an "easy to understand" linear form with respect to the pre-defined variables which are directly dependent on the diabatic potentials and coupling strengths found in the diabatic matrix. Its most important feature (an essential criterion to be selected for modelling the triply degenerate seam pathway) is the ability to predict the existence of an uniquely defined triply degenerate iso-energetic geometry among the chosen coupled states in addition to the prediction of the existence of many doubly degenerate iso-energetic geometries in those states and hence can be adaptable to any general molecular system where such triply or doubly degenerate geometries are believed to occur. The title ion is one among them where many doubly iso-energetic geometries were located but not the triply degenerate one as it is a three atomic system unlike the polyatomic case where the triply degenerate geometry will most likely to be found. To do this work, one requires the knowledge of four asymptotic diatomic curves upon atom+diatom dissociation whose correct correlated spectroscopic states are O2 + ( X 2 Π g ) ${(X\,^2 {\rm{\Pi }}_g )}$ , O2 ( X 3 Σ g - ) ${(X\,^3 {\rm{\Sigma }}_g^ - )}$ , O2 + ( a 4 Π u ) ${(a\,^4 {\rm{\Pi }}_u )}$ , OH+ ( X 3 Σ - ) ${(X\,^3 {\rm{\Sigma }}^ - )}$ . The quality and the characteristics of analytical surface of the ion is discussed well in detail.

Formation of Listeria monocytogenes persister cells in the produce-processing environment.

Persisters are a subpopulation of growth-arrested cells that possess transient tolerance to lethal doses of antibiotics and can revert to an active state under the right conditions. Persister cells are considered as a public health concern. This study examined the formation of persisters by Listeria monocytogenes (LM) in an environment simulating a processing plant for leafy green production. Three LM strains isolated from California produce-processing plants and packinghouses with the strongest adherence abilities were used for this study. The impact of the cells' physiological status, density, and nutrient availability on the formation of persisters was also determined. Gentamicin at a dose of 100 mg/L was used for the isolation and screening of LM persisters. Results showed that the physiological status differences brought by culture preparation methods (plate-grown vs. broth-grown) did not impact persister formation (P > 0.05). Instead, higher persister ratios were found when cell density increased (P < 0.05). The formation of LM persister cells under simulated packinghouse conditions was tested by artificially inoculating stainless steel coupons with LM suspending in media with decreasing nutrient levels: brain heart infusion broth (1366 mg/L O2), produce-washing water with various organic loads (1332 mg/L O2 and 652 mg/L O2, respectively), as well as sterile Milli-Q water. LM survived in all suspensions at 4 °C with 85 % relative humidity for 7 days, with strain 483 producing the most persister cells (4.36 ± 0.294 Log CFU/coupon) on average. Although persister cell levels of LM 480 and 485 were reasonably steady in nutrient-rich media (i.e., BHI and HCOD), they declined in nutrient-poor media (i.e., LCOD and sterile Milli-Q water) over time. Persister populations decreased along with total viable cells, demonstrating the impact of available nutrients on the formation of persisters. The chlorine sensitivity of LM persister cells was evaluated and compared with regular LM cells. Results showed that, despite their increased tolerance to the antibiotic gentamicin, LM persisters were more susceptible to chlorine treatments (100 mg/L for 2 min) than regular cells.

Protective Effect of Thyme and Chestnut Honeys Enriched with Bee Products against Benzo(a)pyrene-Induced DNA Damage.

The aim of the present study was to validate the cytotoxicity, genotoxicity, and preventive potential against benzo(a)pyrene (BaP)-induced DNA damage of nine samples of thyme and chestnut honeys enriched with bee products (royal jelly and propolis, 2-10%). Cell viability was determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (0-250 mg/mL) to select nontoxic concentrations, and DNA damage (0.1-10 µg/mL) was evaluated by the alkaline single-cell gel electrophoresis or comet assay. Treatment with honey samples or royal jelly and propolis did not affect the viability of HepG2 cells up to 100 and 50 mg/mL, respectively. Treatment with 100 µM BaP significantly increased (p ≤ 0.001) the levels of the DNA strand breaks. None of the tested concentrations (0.1-10 µg/mL) of the honey samples (thyme and chestnut), royal jelly, and propolis caused DNA damage per se. All tested samples at all the concentrations used decreased the genotoxic effect of BaP. In addition, all mixtures of thyme or chestnut honeys with royal jelly or propolis showed a greater protective effect against BaP than the samples alone, being the thyme and chestnut honey samples enriched with 10% royal jelly and 10% propolis the most effective (70.4% and 69.4%, respectively). The observed protective effect may be associated with the phenolic content and antioxidant capacity of the studied samples. In conclusion, the thyme and chestnut honey samples enriched with bee products present potential as natural chemoprotective agents against the chemical carcinogen BaP.

Enhancement of the Antioxidant Capacity of Thyme and Chestnut Honey by Addition of Bee Products.

Honey consumption and imports have increased in recent years, and it is considered by consumers to be a healthy alternative to more commonly used sweeteners. Honey contains a mixture of polyphenols and antioxidant compounds, and the botanical origin and geographical area of collection play an important role on its chemical composition. The present study investigated the physicochemical properties, total phenolic content and antioxidant capacity of Spanish thyme honey and chestnut honey, and their mixtures with royal jelly (2% and 10%) and propolis (2% and 10%). The analysis of the physicochemical parameters of both honey samples showed values within the established limits. Propolis showed the highest value of total phenolic content (17.21-266.83 mg GAE/100 g) and antioxidant capacity (DPPH, ORAC and ABTS assays; 0.63-24.10 µg eq. Tx/g, 1.61-40.82 µg eq. Tx/g and 1.89-68.54 µg eq. Tx/g, respectively), and significantly reduced ROS production in human hepatoma cells. In addition, mixtures of honey with 10% of propolis improved the results obtained with natural honey, increasing the value of total phenolic content and antioxidant capacity. A significant positive correlation was observed between total phenolic compounds and antioxidant capacity. Therefore, the antioxidant capacity could be attributed to the phenolic compounds present in the samples, at least partially. In conclusion, our results indicated that thyme and chestnut honey supplemented with propolis can be an excellent natural source of antioxidants and could be incorporated as a potential food ingredient with biological properties of technological interest, added as a preservative. Moreover, these mixtures could be used as natural sweeteners enriched in antioxidants and other bioactive compounds.