Exposure of the grass shrimp, Palaemonetes pugio, to antimicrobial compounds affects associated Vibrio bacterial density and development of antibiotic resistance

Antimicrobial compounds are widespread, emerging contaminants in the aquatic environment and may threaten ecosystem and human health. This study characterized effects of antimicrobial compounds common to human and veterinary medicine, aquaculture, and consumer personal care products [erythromycin (ERY), sulfamethoxazole (SMX), oxytetracycline (OTC), and triclosan (TCS)] in the grass shrimp Palaemonetes pugio. The effects of antimicrobial treatments on grass shrimp mortality and lipid peroxidation activity were measured. The effects of antimicrobial treatments on the bacterial community of the shrimp were then assessed by measuring Vibrio density and testing bacterial isolates for antibiotic resistance. TCS (0.33 mg/L) increased shrimp mortality by 37% and increased lipid peroxidation activity by 63%. A mixture of 0.33 mg/L TCS and 60 mg/L SMX caused a 47% increase in shrimp mortality and an 88% increase in lipid peroxidation activity. Exposure to SMX (30 mg/L or 60 mg/L) alone and to a mixture of SMX/ERY/OTC did not significantly affect shrimp survival or lipid peroxidation activity. Shrimp exposure to 0.33 mg/L TCS increased Vibrio density 350% as compared to the control whereas SMX, the SMX/TCS mixture, and the mixture of SMX/ERY/OTC decreased Vibrio density 78-94%. Increased Vibrio antibiotic resistance was observed for all shrimp antimicrobial treatments except for the mixture of SMX/ERY/OTC. Approximately 87% of grass shrimp Vibrio isolates displayed resistance to TCS in the control treatment suggesting a high level of TCS resistance in environmental Vibrio populations. The presence of TCS in coastal waters may preferentially increase the resistance and abundance of pathogenic bacteria. These results indicate the need for further study into the potential interactions between antimicrobials, aquatic organisms, and associated bacterial communities.

Imaging heterogeneity of peptide delivery and binding in solid tumors using SPECT imaging and MRI

Background

As model system, a solid-tumor patient-derived xenograft (PDX) model characterized by high peptide receptor expression and histological tissue homogeneity was used to study radiopeptide targeting. In this solid-tumor model, high tumor uptake of targeting peptides was expected. However, in vivo SPECT images showed substantial heterogeneous radioactivity accumulation despite homogenous receptor distribution in the tumor xenografts as assessed by in vitro autoradiography. We hypothesized that delivery of peptide to the tumor cells is dictated by adequate local tumor perfusion. To study this relationship, sequential SPECT/CT and MRI were performed to assess the role of vascular functionality in radiopeptide accumulation.

Methods

High-resolution SPECT and dynamic contrast-enhanced (DCE)-MRI were acquired in six mice bearing PC295 PDX tumors expressing the gastrin-releasing peptide (GRP) receptor. Two hours prior to SPECT imaging, animals received 25 MBq ¹¹¹In(DOTA-(βAla)2-JMV594) (25 pmol). Images were acquired using multipinhole SPECT/CT. Directly after SPECT imaging, MR images were acquired on a 7.0-T dedicated animal scanner. DCE-MR images were quantified using semi-quantitative and quantitative models. The DCE-MR and SPECT images were spatially aligned to compute the correlations between radioactivity and DCE-MRI-derived parameters over the tumor.

Results

Whereas histology, in vitro autoradiography, and multiple-weighted MRI scans all showed homogenous tissue characteristics, both SPECT and DCE-MRI showed heterogeneous distribution patterns throughout the tumor. The average Spearman’s correlation coefficient between SPECT and DCE-MRI ranged from 0.57 to 0.63 for the “exchange-related” DCE-MRI perfusion parameters.

Conclusions

A positive correlation was shown between exchange-related DCE-MRI perfusion parameters and the amount of radioactivity accumulated as measured by SPECT, demonstrating that vascular function was an important aspect of radiopeptide distribution in solid tumors. The combined use of SPECT and MRI added crucial information on the perfusion efficiency versus radiopeptide uptake in solid tumors and showed that functional tumor characteristics varied locally even when the tissue appeared homogenous on current standard assessment techniques.

Electronic supplementary material

The online version of this article (doi:10.1186/s13550-016-0160-4) contains supplementary material, which is available to authorized users.

Poly(ethylene) glycols and mechanochemistry for the preparation of bioactive 3,5-disubstituted hydantoins

Mechanochemistry was effective for the preparation of 3,5-disubstituted hydantoins from α-amino methyl esters, using either 1,1′-carbonyldiimidazole (CDI) or alkyl isocyanates.

Clinical Course of acute-on-chronic liver failure syndrome and effects on prognosis

Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation (AD) of cirrhosis, organ failure(s), and high 28-day mortality. We investigated whether assessments of patients at specific time points predicted their need for liver transplantation (LT) or the potential futility of their care. We assessed clinical courses of 388 patients who had ACLF at enrollment, from February through September 2011, or during early (28-day) follow-up of the prospective multicenter European Chronic Liver Failure (CLIF) ACLF in Cirrhosis study. We assessed ACLF grades at different time points to define disease resolution, improvement, worsening, or steady or fluctuating course. ACLF resolved or improved in 49.2%, had a steady or fluctuating course in 30.4%, and worsened in 20.4%. The 28-day transplant-free mortality was low-to-moderate (6%-18%) in patients with nonsevere early course (final no ACLF or ACLF-1) and high-to-very high (42%-92%) in those with severe early course (final ACLF-2 or -3) independently of initial grades. Independent predictors of course severity were CLIF Consortium ACLF score (CLIF-C ACLFs) and presence of liver failure (total bilirubin ≥12 mg/dL) at ACLF diagnosis. Eighty-one percent had their final ACLF grade at 1 week, resulting in accurate prediction of short- (28-day) and mid-term (90-day) mortality by ACLF grade at 3-7 days. Among patients that underwent early LT, 75% survived for at least 1 year. Among patients with ≥4 organ failures, or CLIF-C ACLFs >64 at days 3-7 days, and did not undergo LT, mortality was 100% by 28 days.

CONCLUSIONS

Assessment of ACLF patients at 3-7 days of the syndrome provides a tool to define the emergency of LT and a rational basis for intensive care discontinuation owing to futility.

The Big Impact of Small Groups on College Drinking

College drinking is a problem with severe academic, health, and safety consequences. The underlying social processes that lead to increased drinking activity are not well understood. Social Norms Theory is an approach to analysis and intervention based on the notion that students' misperceptions about the drinking culture on campus lead to increases in alcohol use. In this paper we develop an agent-based simulation model, implemented in MATLAB, to examine college drinking. Students' drinking behaviors are governed by their identity (and how others perceive it) as well as peer influences, as they interact in small groups over the course of a drinking event. Our simulation results provide some insight into the potential effectiveness of interventions such as social norms marketing campaigns.

Language Discordance and Patient- Centered Care in Occupational Therapy: A Case Study

The accumulative burden of a growing non-English speaking minority population and health disparities in the United States demonstrate the urgency of examining occupational therapy practices and defining care that is timely, effective, safe, and patient-centered. In this context, we investigate an occupational therapy episode of care from the perspectives of patient, caregiver, and primary occupational therapy care provider. Treatment sessions were observed and one-on-one semistructured interviews were conducted with the participants. Several themes describing areas of concern in communication and care delivery emerged, including expectations for care, the therapy relationship, professional identity, and pragmatic constraints. The use of untrained interpreters compromised treatment effectiveness and safety. This case highlights potential areas of concern in therapy when working with a diverse patient population. Abundant opportunities exist for occupational therapy to situate itself as an equitable, responsive, valuable, and essential service.

Microwave-ultrasound simultaneous irradiation: a hybrid technology applied to ring closing metathesis

Glycerol micelles were suitable nanoreactors for ring-closing metathesis reaction activated by a hybrid microwave-ultrasound reactor. Nine different Ru-catalysts were investigated.

Impact of fatigue on outcome of selective serotonin reuptake inhibitor treatment: secondary analysis of STAR*D

OBJECTIVE

To explore relationships between baseline and changes in fatigue during treatment with outcomes in patients with major depressive disorder (MDD) receiving citalopram monotherapy.

RESEARCH DESIGN AND METHODS

Secondary analyses of data from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) Level 1 treatment phase (≤14 weeks citalopram monotherapy). Fatigue was assessed with item 14 on energy level from the 16-item Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR16; scored 0-3: 0 = no fatigue, 3 = maximal fatigue); prospective fatigue: assessment of fatigue at Level 1 entry and exit (no fatigue, treatment-emergent fatigue, remitted fatigue, or residual fatigue).

CLINICAL TRIAL REGISTRATION

Http://clinicaltrials.gov, NCT00021528.

MAIN OUTCOME MEASURES

Remission of depressive symptoms (17-item Hamilton Rating Scale for Depression ≤7 or QIDS-SR16 ≤5); Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form; Short-Form Health Survey Mental and Physical subscales; and Work and Social Adjustment Scale (WSAS).

RESULTS

At baseline, of 2868 patients included in the analyses, 5.5% had a QIDS-SR16 item 14 score of 0; 22.9%, a score of 1; 53.6%, a score of 2; and 18.0%, a score of 3. During Level 1 treatment, 3.5% of patients had no prospective fatigue, 2.1% had treatment-emergent fatigue, 33.6% had fatigue remitting during treatment, and 60.8% had residual fatigue. Female gender, unemployment, fewer years of education, and lower monthly income were significantly associated with higher rates of baseline fatigue (all P < 0.0001). Higher levels of baseline or prospective fatigue were associated with reduced likelihood of remission, decreased overall satisfaction (P < 0.0001), and reduced mental and physical function at outcome (P ≤ 0.05). Patients with higher baseline or prospective fatigue reported higher WSAS total scores (P < 0.0001), indicative of more severe functional impairment.

CONCLUSIONS

Lower baseline fatigue and remission of fatigue during antidepressant treatment in patients with MDD are associated with higher rates of remission of depressive symptoms and better function and quality of life. Study limitations include use of the STAR*D Level 1 sample (citalopram as only antidepressant), use of a proxy measure of energy/fatigue (item 14 from the QIDS-SR16), and the secondary post-hoc analysis design.

Triazole GHS-R1a antagonists JMV4208 and JMV3002 attenuate food intake, body weight, and adipose tissue mass in mice

The only peripherally released orexigenic hormone, ghrelin, plays a key role in food intake and body weight regulation. Antagonizing the ghrelin receptor, GHS-R1a, represents a promising approach for anti-obesity therapy. In our study, two novel GHS-R1a antagonists JMV4208 and JMV3002, which are trisubstituted 1,2,4-triazoles, decreased food intake in fasted lean mice in a dose-dependent manner, with ED50 values of 5.25 and 2.05 mg/kg, respectively. Both compounds were stable in mouse blood, with half-lives of 90 min (JMV4208) and 60 min (JMV3002), and disappeared from the blood 8h after administration. Fourteen days of treatment with the ghrelin antagonists (20 mg/kg twice a day) decreased food intake, body weight and adipose tissue mass in mice with diet-induced obesity (DIO). These results are likely attributable to an impact on food intake reduction and an attenuated expression of the lipogenesis-promoting enzymes (acetyl-CoA carboxylase 1 in subcutaneous fat and fatty acid synthase in subcutaneous and intraperitoneal fat). The decrease in fat mass negatively impacted circulating leptin levels. These data suggest that JMV4208 and JMV3002 could be useful therapeutic agents for the treatment of obesity.