Immunofluorescence Visualization of Polycyclic Aromatic Hydrocarbon Mixtures in the Eastern Oyster Crassostrea virginica.

Bivalve mollusks including oysters have low metabolic potential and are therefore susceptible to accumulating high levels of lipophilic organic contaminants such as polycyclic aromatic hydrocarbons (PAHs). Human exposure to PAHs via consumption of this important commercial shellfish can be a serious public health concern in areas where high PAH contamination exists. Previous PAH immunohistochemical studies have been limited to laboratory-based exposures focusing on one or a few individual PAH compounds. To date, such studies have yet to explore PAH accumulation in oysters, known to have some of the highest levels of PAHs across different food products. Using a monoclonal antibody selective for a range of three- to five-ring PAHs, we present a method to detect and localize complex mixtures of PAHs in oyster tissues via fluorescent immunohistochemistry. Observed immunofluorescence intensity followed a similar trend as measured levels of PAHs in oyster interstitial fluid from PAH-contaminated sites and oysters exposed to the water accommodated fraction of crude oil. This method will be valuable in understanding internal partitioning mechanisms of PAH-exposed oysters and will have important applications in studies on PAH distribution in the tissues of additional organisms for environmental, medical, or veterinary purposes. Environ Toxicol Chem 2023;42:475-480. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Focused ultrasound radiosensitizes human cancer cells by enhancement of DNA damage.

PURPOSE: High-intensity focused ultrasound (HIFU/FUS) has expanded as a noninvasive quantifiable option for hyperthermia (HT). HT in a temperature range of 40-47 °C (thermal dose CEM43 ≥ 25) could work as a sensitizer to radiation therapy (RT). Here, we attempted to understand the tumor radiosensitization effect at the cellular level after a combination treatment of FUS+RT. METHODS: An in vitro FUS system was developed to induce HT at frequencies of 1.147 and 1.467 MHz. Human head and neck cancer (FaDU), glioblastoma (T98G), and prostate cancer (PC-3) cells were exposed to FUS in ultrasound-penetrable 96-well plates followed by single-dose X­ray irradiation (10 Gy). Radiosensitizing effects of FUS were investigated by cell metabolic activity (WST­1 assay), apoptosis (annexin V assay, sub-G1 assay), cell cycle phases (propidium iodide staining), and DNA double-strand breaks (γH2A.X assay). RESULTS: The FUS intensities of 213 (1.147 MHz) and 225 W/cm2 (1.467 MHz) induced HT for 30 min at mean temperatures of 45.20 ± 2.29 °C (CEM43 = 436 ± 88) and 45.59 ± 1.65 °C (CEM43 = 447 ± 79), respectively. FUS improves the effect of RT significantly by reducing metabolic activity in T98G cells 48 h (RT: 96.47 ± 8.29%; FUS+RT: 79.38 ± 14.93%; p = 0.012) and in PC-3 cells 72 h (54.20 ± 10.85%; 41.01 ± 11.17%; p = 0.016) after therapy, but not in FaDu cells. Mechanistically, FUS+RT leads to increased apoptosis and enhancement of DNA double-strand breaks compared to RT alone in T98G and PC-3 cells. CONCLUSION: Our in vitro findings demonstrate that FUS has good potential to sensitize glioblastoma and prostate cancer cells to RT by mainly enhancing DNA damage.

Focused Ultrasound-Induced Cavitation Sensitizes Cancer Cells to Radiation Therapy and Hyperthermia.

Focused ultrasound (FUS) has become an important non-invasive therapy for solid tumor ablation via thermal effects. The cavitation effect induced by FUS is thereby avoided but applied for lithotripsy, support drug delivery and the induction of blood vessel destruction for cancer therapy. In this study, head and neck cancer (FaDu), glioblastoma (T98G), and prostate cancer (PC-3) cells were exposed to FUS by using an in vitro FUS system followed by single-dose X-ray radiation therapy (RT) or water bath hyperthermia (HT). Sensitization effects of short FUS shots with cavitation (FUS-Cav) or without cavitation (FUS) to RT or HT (45 °C, 30 min) were evaluated. FUS-Cav significantly increases the sensitivity of cancer cells to RT and HT by reducing long-term clonogenic survival, short-term cell metabolic activity, cell invasion, and induction of sonoporation. Our results demonstrated that short FUS treatment with cavitation has good potential to sensitize cancer cells to RT and HT non-invasively.

Acute and long-term manganese exposure and subsequent accumulation in relation to idiopathic blindness in the American lobster, Homarus americanus.

Manganese (Mn) is a hypoxic reactive metal commonly found in marine sediments. Under hypoxic conditions the metal becomes fully reduced to Mn2+ and is biologically available to the benthic community for uptake. Mn is also a potent neurotoxin and it may play a role in the etiology of idiopathic blindness that has been observed in American lobsters. An acute exposure study was designed to expose American lobster, Homarus americanus, to 0, 20, 80, 150, and 300 mg L-1 (ppm) for 96 hs to explore disparities in Mn accumulation among several tissues: optic nerve, brain, hepatopancreas, muscle, hemolymph, gill, and exoskeleton. These concentrations were based on realistic pore-water concentrations (20 mg L-1), high sediment concentrations (80 mg L-1), and unrealistically high concentrations to determine lethality (150 and 300 mg L-1). A positive correlation between Mn accumulation and exposure concentration was observed in all tissues examined. In the internal tissues, manganese concentrations showed a high affinity towards brain, optic nerve, and hemolymph. In the exoskeleton and gills, Mn concentrations were also high, possibly because of internal uptake as well as external adsorption. Concentrations of Mn in tissues from the acute exposure study followed the accumulation pattern: hemolymph > gill > exoskeleton > optic nerve > brain > hepatopancreas = muscle. A long-term exposure study lasting seven weeks was designed to investigate the potential link between high Mn exposure and idiopathic blindness, a condition that affects an estimated 50 % of the adult American lobster population off Southern New England (SNE), USA. A comparison of these exposure studies showed evidence of time-dependent Mn accumulation in brain, muscle, exoskeleton, and gill tissue. Although the relationship between Mn exposure and blindness was not apparent, there was a modest trend in the development of blindness (Chi-square, p = 0.102) in animals exposed to a high concentration (150 mg L-1) of the metal. With no mortalities occurring in the acute study and only one mortality in the long-term study, it is highly unlikely that Mn is acutely toxic to American lobsters at environmentally relevant concentrations. Its potential role in idiopathic blindness remains to be determined.

Near real-time, on-site, quantitative analysis of PAHs in the aqueous environment using an antibody-based biosensor.

Rapid, on-site, quantitative assessments of dissolved polycyclic aromatic hydrocarbons (PAHs) were demonstrated for two field applications. The platform, a KinExA Inline Sensor (Sapidyne Instruments), employed the monoclonal anti-PAH antibody, 7B2.3, which has specificity for 3- to 5-ring PAHs. A spatial study was conducted near a dredging site where contaminated sediments were being removed, and a temporal study was performed during a rainfall event. Most importantly, the generation of near real-time data guided management decisions in the field and determined proper sampling protocols for conventional analyses. The method was able to determine PAH concentrations as low as 0.3 µg/L, within 10 min of sample acquisition, and to assess 80+ samples (not including standards and blanks) in less than 3 d. These results were compared with a laboratory-based gas chromatography-mass spectrometry method in which a wide array of PAHs, including alkylated homologs, were examined. This system shows great promise as a field instrument for the rapid monitoring of PAH pollution.

Comparing cancer patients who enroll in a smoking cessation program at a comprehensive cancer center with those who decline enrollment.

BACKGROUND: Despite the availability of smoking interventions for cancer patients, many eligible patients decline enrollment into such programs. We examined reasons patients provide for declining smoking treatment and compared treatment decliners to enrollees. METHODS: Eligible cancer patients (N = 231) were offered smoking cessation treatment. During recruitment, demographic, medical (eg, cancer stage), and smoking-related behavioral (eg, readiness to quit) data were collected, and decliners stated a reason for refusal. Patients who enrolled in the cessation program (N = 109) were compared with those who declined (N = 122) in terms of recruitment data, and reasons for declining were compiled. RESULTS: Decliners were significantly more likely to: (1) have head and neck cancer (vs lung cancer); (2) exhibit fewer physical symptoms (eg, shortness of breath); (3) report a lower readiness to quit smoking; (4) indicate no intention to quit smoking; and (5) smoke fewer cigarettes. A preference to quit without professional assistance was the most common reason for declining treatment. CONCLUSIONS: Our findings highlight important differences between patients who enroll in a smoking cessation program and those who decline and underscore the need for motivational interventions to facilitate enrollment into smoking interventions for cancer patients.

Endobronchial therapy of neoplasms.

The techniques and modalities provided by interventional pulmonology play a major role in the management of patients with symptomatic airways obstruction. The majority of these obstructions are part of pulmonary involvement by primary lung neoplasms or metastatic lesions from other organs. Benign lesions, although capable of producing similar symptoms, are more rare. Performance of successful interventional pulmonology is dependent on the skill and dexterity of the operator paired with a highly trained and dedicated ancillary team of nurses, anesthetists, and respiratory therapists. Successful endobronchial management of airway obstruction not only provides significant improvement in patients' quality of life, it also adds to their survival time. Both results fulfill the stated goals of appropriate and desired palliative therapy. Interventional pulmonology also contributes to research of the process of lung carcinogenesis and the introduction of targeted therapy for early minimally invasive cancer and the potential chemotherapy of premalignant lesions.

Processes of change related to smoking behavior among cancer patients.

PURPOSE: The purpose of this study was to examine the degree to which transtheoretical model processes of change (methods and strategies for cessation) were associated with smoking status and quitting behavior (ie, intentions and attempts to quit) among patients with head and neck or lung cancer. The relationship between medical variables and processes of change was also explored. DESCRIPTION OF STUDY: Twenty-nine smokers and 45 abstainers who were recruited from treatment clinics within a comprehensive cancer center completed a brief survey. Multivariate analysis of variance and Pearson correlation procedures were used to evaluate hypothesized relationships. RESULTS: As hypothesized, quitters used behavioral processes such as counter-conditioning and reinforcement management significantly more than smokers and used self-reevaluation, an experiential process, significantly less than smokers. Contrary to the hypothesis, however, quit attempts and intentions were associated with both experiential (ie, consciousness raising and self-reevaluation) and behavioral (ie, reinforcement management and self-liberation) processes of change. Use of the processes of change was not influenced by medical variables, including cancer type, illness phase, disease stage, type of current medical treatment, and duration of illness. CLINICAL IMPLICATIONS: These findings suggest that behavioral counseling to promote smoking cessation for patients with cancer should involve assisting the patient to do the following: develop an awareness of the health risks related to continued smoking; devise and use alternative behaviors; implement the use of reinforcement strategies for cessation successes; and develop a sense of confidence and commitment about quitting as well as healthy lifestyle values. These strategies are discussed within the context of models and guidelines for smoking cessation in clinical practice.