Biofilm Formation on Dental Implant Biomaterials by Staphylococcus aureus Strains Isolated from Patients with Cystic Fibrosis

Implants made of ceramic and metallic elements, which are used in dentistry, may either promote or hinder the colonization and adhesion of bacteria to the surface of the biomaterial to varying degrees. The increased interest in the use of dental implants, especially in patients with chronic systemic diseases such as cystic fibrosis (CF), is caused by an increase in disease complications. In this study, we evaluated the differences in the in vitro biofilm formation on the surface of biomaterials commonly used in dentistry (Ti-6Al-4V, cobalt-chromium alloy (CoCr), and zirconia) by Staphylococcus aureus isolated from patients with CF. We demonstrated that S. aureus adherence and growth depends on the type of material used and its surface topography. Weaker bacterial biofilm formation was observed on zirconia surfaces compared to titanium and cobalt-chromium alloy surfaces. Moreover, scanning electron microscopy showed clear differences in bacterial aggregation, depending on the type of biomaterial used. Over the past several decades, S. aureus strains have developed several mechanisms of resistance, especially in patients on chronic antibiotic treatment such as CF. Therefore, the selection of an appropriate implant biomaterial with limited microorganism adhesion characteristics can affect the occurrence and progression of oral cavity infections, particularly in patients with chronic systemic diseases.     

Birth Control Sabotage as a Correlate of Women's Sexual Health Risk: An Exploratory Study

IntroductionTo explore associations between birth control sabotage, a form of reproductive coercion, and women's sexual risk among women attending family planning health centers. Data were collected from a 2017 cross-sectional online survey of 675 women who attended Connecticut Planned Parenthood centers. Participants reported birth control sabotage; sexual risk (i.e., inconsistent condom use during vaginal and anal sex in the past 6 months, lifetime sexually transmitted infection diagnosis, lifetime exchange sex [trading sex for money, drugs, or other goods], and multiple sexual partners in the past 6 months); and sociodemographics. Bivariate and multivariable logistic regression models were used to examine associations between birth control sabotage and women's sexual risk.ResultsOne in six women (16.4%; n = 111) reported experiencing birth control sabotage. Women who reported birth control sabotage had a greater odds of ever having an sexually transmitted infection (adjusted odds ratio, 2.18; 95% confidence interval, 1.31–3.60; p = .003), ever engaging in exchange sex (adjusted odds ratio, 2.77; 95% confidence interval, 1.17–6.53; p = .020), and having multiple sexual partners in the past 6 months (adjusted odds ratio, 1.96; 95% confidence interval, 1.21–3.18; p = .006).ConclusionsOur findings demonstrate increased engagement in sexual risk taking among women who reported birth control sabotage compared with women did not.     

Health Beliefs and Preventive Behaviors Among Adults During the Early COVID-19 Pandemic in the United States: a Latent Class Analysis

Prevention Science - The objectives of this study are to (1) characterize patterns of preventive behaviors 3 months after the COVID-19 pandemic was declared a national emergency in the USA...     

Estradiol metabolism by complementary deoxyribonucleic acid-expressed human cytochrome P450s

Twelve forms of human cytochrome P450 were synthesized in human hepatoma Hep G2 cells by means of cDNA-directed expression using vaccinia virus. The cDNA-expressed enzymes were tested for their ability to oxidize estradiol. Incubation of [14C]estradiol with cell lysates containing P450 IA2 resulted in the production of 2-hydroxy and 4-hydroxy metabolites with substrate turnovers of 2.74 and 0.27 min-1, respectively. P450s IIIA3 and IIIA4 yielded the same metabolites at about one third the rate of P450 IA2. Low levels of estradiol hydroxylation were also catalyzed by P450s IIC9, IIIA5, and IVB1. Six other P450 forms yielded no detectable metabolism. The roles of P450s IA2, IIA3, and IIIA4 were further established by immunoinhibition using antirat P450 antibodies. Antibody that specifically binds to P450 IIIA3 and IIIA4 inhibited 60-70% of estradiol hydroxylation, and antibody against P450 IA2 inhibited 20-40% of the estradiol hydroxylase activity in microsomes from two human liver specimens, suggesting that these enzymes constitute the major forms catalyzing estradiol oxidation in human liver. Immunoinhibition results also suggest that 2-hydroxy- and/or 4-hydroxycatechol estrogens are further metabolized to other yet uncharacterized metabolites by P450s IIIA3 and IIIA4.     

Involvement of p53 in insulin-like growth factor binding protein-3 regulation in the breast cancer cell response to DNA damage

Chemotherapy drugs that induce apoptosis by causing DNA double-strand breaks, upregulate the tumor suppressor p53. This study investigated the regulation of the growth-regulatory protein insulin-like growth factor binding protein-3 (IGFBP-3), a p53 target, by DNA-damaging agents in breast cancer cells. IGFBP-3 was upregulated 1.4- to 13-fold in response to doxorubicin and etoposide in MCF-10A, Hs578T, MCF-7 and T47D cells, which express low to moderate basal levels of IGFBP-3. In contrast, IGFBP-3 was strongly downregulated by these agents in cells with high basal levels of IGFBP-3 (MDA-MB-231, MDA-MB-436 and MDA-MB-468). In MDA-MB-468 cells containing the R273H p53 mutation, reported to display gain-of-function properties, chemotherapy-induced suppression of IGFBP-3 was not reversed by the p53 reactivating drug, PRIMA-1, or by p53 silencing, suggesting that the decrease in IGFBP-3 following DNA damage is not a mutant p53 gain-of-function response. SiRNA-mediated downregulation of endogenous IGFBP-3 modestly attenuated doxorubicin-induced apoptosis in MDA-MB-468 and Hs578T cells. IGFBP-3 downregulation in some breast cancer cell lines in response to DNA-damaging chemotherapy may have clinical implications because suppression of IGFBP-3 may modulate the apoptotic response. These observations provide further evidence that endogenous IGFBP-3 plays a role in breast cancer cell responsiveness to DNA damaging therapy.     

Ecology of sand flies in a low-density residential rural area,with mixed forest/agricultural exploitation,in north-eastern Brazil

Cutaneous leishmaniasis caused by Leishmania braziliensis is endemic in Brazil, where Lutzomyia whitmani is the most important vector involved in the transmission to humans, particularly in the peridomestic environment. Herein, we assessed the ecology of sand flies, including Lu. whitmani, in a low-density residential rural area with mixed forest/agricultural exploitation in north-eastern Brazil, where cutaneous leishmaniasis is endemic. Particularly, we hypothesized that sand fly abundance was correlated with climatic variables. Sand fly collections were carried out monthly from August 2013 to August 2014, using seven CDC light traps, for three consecutive nights, in three kinds of environments: indoor, peridomicile and forest. Collected sand flies were identified based on morphology and females of Lu. whitmani (n = 169), Lu. amazonensis (n = 134) and Lu. complexa (n = 21) were selected and tested by PCR for Leishmania (Viannia) spp. In total, 5167 sand flies belonging to 19 species were identified, being that Lu. choti (43.2%) was the most frequent species, followed by Lu. amazonensis (16.6%), Lu. whitmani (15.8%), Lu. sordellii (10.7%) and Lu. quinquefer (5.8%), which together represented over 90% of the collected sand flies. All females tested by PCR were negative. The number of sand flies collected daily was positively correlated with temperature and negatively correlated with rainfall and relative humidity. Furthermore, there was a positive correlation between daily number of sand flies and daily average saturation deficit. This study points out that the number of sand flies captured daily is correlated to climatic variables, including saturation deficit, which may represent a useful parameter for monitoring sand fly populations in leishmaniasis-endemic areas.     

Occupational asthma follow-up — which markers are elevated in exhaled breath condensate and plasma?

Objectives

To search for optimal markers in the exhaled breath condensate (EBC), plasma and urine that would reflect the activity/severity of occupational asthma (OA) after the withdrawal from the exposure to the allergen.

Material and Methods

Markers of oxidative stress: 8-iso-prostaglandin {ie206-1} (8-isoprostane, 8-ISO), malondialdehyde (MDA), 4-hydroxy-trans-2-nonenale (HNE), cysteinyl leukotrienes (LT) and LTB₄ were determined using liquid chromatography and mass spectrometry in 43 subjects with immunological OA (49.3±11.8 years), removed from the exposure to the sensitizing agent 10.5±6.5 years ago; and in 20 healthy subjects (49.0±14.9 years). EBC was harvested both before and after the methacholine challenge test. In parallel, identical markers were collected in plasma and urine. The results were analyzed together with forced expiratory volume in one second (FEV₁), blood eosinophils, immunoglobulin E (IgE) and eosinophilic cationic protein (ECP) and statistically evaluated (Spearman rank correlation r_S, two- or one-sample t tests and alternatively Kruskal Wallis or pair Wilcoxon tests).

Results

Several parameters of lung functions were lower in the patients (FEV1% predicted, MEF25% and MEF50%, Rtot%, p < 0.001). Shorter time interval since the removal from the allergen exposure correlated with higher ECP (r_S = 0.375) and lower FEV₁%, MEF25% and MEF50% after methacholine challenge (r_S = ?0.404, ?0.425 and ?0.532, respectively). In the patients, IgE (p < 0.001) and ECP (p = 0.009) was increased compared to controls. In EBC, 8-ISO and cysteinyl LTs were elevated in the asthmatics initially and after the challenge. Initial 8-ISO in plasma correlated negatively with FEV₁ (r_S = ?0.409) and with methacholine PD₂₀ (r_S = ?0.474). 8-ISO in plasma after the challenge correlated with IgE (r_S = 0.396).

Conclusions

The improvement in OA is very slow and objective impairments persist years after removal from the exposure. Cysteinyl LTs and 8-ISO in EBC and 8-ISO in plasma might enrich the spectrum of useful objective tests for the follow-up of OA.