Airborne particles containing elemental carbon (EC) are currently at the forefront of scientific and regulatory scrutiny, including black carbon, carbon black, and engineered carbon-based ...nanomaterials, e.g., carbon nanotubes, fullerenes, and graphene. Scientists and regulators sometimes group these EC-containing particles together, for example, interchangeably using the terms carbon black and black carbon despite one being a manufactured product with well-controlled properties and the other being an undesired, incomplete-combustion byproduct with diverse properties. In this critical review, we synthesize information on the contrasting properties of EC-containing particles in order to highlight significant differences that can affect hazard potential. We demonstrate why carbon black should not be considered a model particle representative of either combustion soots or engineered carbon-based nanomaterials. Overall, scientific studies need to distinguish these highly different EC-containing particles with care and precision so as to forestall unwarranted extrapolation of properties, hazard potential, and study conclusions from one material to another.
•Major classes of elemental carbon-containing particles have distinct properties.•Despite similar names, carbon black should not be confused with black carbon.•Carbon black is distinguished by a high EC content and well-controlled properties.•Black carbon particles are characterized by their heterogenous properties.•Carbon black is not a model particle representative of engineered nanomaterials.
This review demonstrates the significant physical and chemical distinctions between elemental carbon-containing particles e.g., carbon black, black carbon, and engineered nanomaterials.
Hepatocellular carcinoma (HCC) cells are metabolically distinct from normal hepatocytes by expressing the high-affinity hexokinase (HK2) and suppressing glucokinase (GCK). This is exploited to ...selectively target HCC. Hepatic HK2 deletion inhibits tumor incidence in a mouse model of hepatocarcinogenesis. Silencing HK2 in human HCC cells inhibits tumorigenesis and increases cell death, which cannot be restored by GCK or mitochondrial binding deficient HK2. Upon HK2 silencing, glucose flux to pyruvate and lactate is inhibited, but TCA fluxes are maintained. Serine uptake and glycine secretion are elevated suggesting increased requirement for one-carbon contribution. Consistently, vulnerability to serine depletion increases. The decrease in glycolysis is coupled to elevated oxidative phosphorylation, which is diminished by metformin, further increasing cell death and inhibiting tumor growth. Neither HK2 silencing nor metformin alone inhibits mTORC1, but their combination inhibits mTORC1 in an AMPK-independent and REDD1-dependent mechanism. Finally, HK2 silencing synergizes with sorafenib to inhibit tumor growth.
Understanding and minimizing coronavirus disease 2019 (COVID‐19) vaccine hesitancy is critical to population health and minimizing health inequities, which continue to be brought into stark relief by ...the pandemic. We investigate questions regarding vaccine hesitancy in a sample (n = 1205) of Arkansas adults surveyed online in July/August of 2020. We examine relationships among sociodemographics, COVID‐19 health literacy, fear of COVID‐19 infection, general trust in vaccines, and COVID‐19 vaccine hesitancy using bivariate analysis and a full information maximum likelihood (FIML) logistic regression model. One in five people (21,21.86%) reported hesitancy to take a COVID‐19 vaccine. Prevalence of COVID‐19 vaccine hesitancy was highest among Black/African Americans (50.00%), respondents with household income less than $25K (30.68%), some college (32.17%), little to no fear of infection from COVID‐19 (62.50%), and low trust in vaccines in general (55.84%). Odds of COVID‐19 vaccine hesitancy were 2.42 greater for Black/African American respondents compared to White respondents (p < 0.001), 1.67 greater for respondents with some college/technical degree compared to respondents with a 4‐year degree (p < 0.05), 5.48 greater for respondents with no fear of COVID‐19 infection compared to those who fear infection to a great extent (p < 0.001), and 11.32 greater for respondents with low trust in vaccines (p < 0.001). Sociodemographic differences in COVID‐19 vaccine hesitancy raise concerns about the potential of vaccine implementation to widen existing health disparities in COVID‐19 related infections, particularly among Black/African Americans. Fear of infection and general mistrust in vaccines are significantly associated with vaccine hesitancy.
Photonic integrated circuits provide a compact and stable platform for quantum photonics. Here we demonstrate a silicon photonics quantum key distribution (QKD) encoder in the first high-speed ...polarization-based QKD field tests. The systems reach composable secret key rates of 1.039 Mbps in a local test (on a 103.6-m fiber with a total emulated loss of 9.2 dB) and 157 kbps in an intercity metropolitan test (on a 43-km fiber with 16.4 dB loss). Our results represent the highest secret key generation rate for polarization-based QKD experiments at a standard telecom wavelength and demonstrate photonic integrated circuits as a promising, scalable resource for future formation of metropolitan quantum-secure communications networks.
There are currently no functional neuromuscular junction (hNMJ) systems composed of human cells that could be used for drug evaluations or toxicity testing in vitro. These systems are needed to ...evaluate NMJs for diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy or other neurodegenerative diseases or injury states. There are certainly no model systems, animal or human, that allows for isolated treatment of motoneurons or muscle capable of generating dose response curves to evaluate pharmacological activity of these highly specialized functional units. A system was developed in which human myotubes and motoneurons derived from stem cells were cultured in a serum-free medium in a BioMEMS construct. The system is composed of two chambers linked by microtunnels to enable axonal outgrowth to the muscle chamber that allows separate stimulation of each component and physiological NMJ function and MN stimulated tetanus. The muscle's contractions, induced by motoneuron activation or direct electrical stimulation, were monitored by image subtraction video recording for both frequency and amplitude. Bungarotoxin, BOTOX® and curare dose response curves were generated to demonstrate pharmacological relevance of the phenotypic screening device. This quantifiable functional hNMJ system establishes a platform for generating patient-specific NMJ models by including patient-derived iPSCs.
•A system in which stem cell derived human myotubes and MNs were cultured in a serum-free medium in a BioMEMS construct.•Directed axonal outgrowth links muscle and MN chambers to allow for physiological NMJ function and MN stimulated tetanus.•The muscle’s contractions were monitored by image subtraction video recording for both frequency and amplitude.•Bungarotoxin, BOTOX® and curare dose response curves were generated for pharmacological relevance of the phenotypic screen.•This hNMJ system establishes a platform for generating patient-specific models using iPSCs for personalized medicine.
Objectives
To present current literature on the topic of odontogenic sinusitis.
Data Source
PubMed literature search for odontogenic sinusitis.
Results
Odontogenic sinusitis is an inflammatory ...condition of the paranasal sinuses that is the result of dental pathology, most often resulting from prior dentoalveolar procedures, infections of maxillary dentition, or maxillary dental trauma. Infections are often polymicrobial with an anaerobe‐predominant microbiome requiring special considerations for antimicrobial therapy. Medical management and treatment of the underlying dental pathology remains a critical initial step in the treatment of odontogenic sinusitis, however recent literature suggests that a significant portion of patients may require endoscopic sinus surgery for successful disease resolution.
Conclusions
This review describes the essential epidemiological and etiological factors, relevant clinical findings and diagnostic modalities, microbiologic and antimicrobial considerations, as well as the medical and surgical treatment approaches commonly utilized for the management of odontogenic sinusitis.
Level of Evidence
NA.
The cochlear implant is one of the most successful medical prostheses, allowing deaf and severely hearing-impaired persons to hear again by electrically stimulating the auditory nerve. A trained ...audiologist adjusts the stimulation settings for good speech understanding, known as "fitting" the implant. This process is based on subjective feedback from the user, making it time-consuming and challenging, especially in paediatric or communication-impaired populations. Furthermore, fittings only happen during infrequent sessions at a clinic, and therefore cannot take into account variable factors that affect the user's hearing, such as physiological changes and different listening environments. Objective audiometry, in which brain responses evoked by auditory stimulation are collected and analysed, removes the need for active patient participation. However, recording of brain responses still requires expensive equipment that is cumbersome to use. An elegant solution is to record the neural signals using the implant itself. We demonstrate for the first time the recording of continuous electroencephalographic (EEG) signals from the implanted intracochlear electrode array in human subjects, using auditory evoked potentials originating from different brain regions. This was done using a temporary recording set-up with a percutaneous connector used for research purposes. Furthermore, we show that the response morphologies and amplitudes depend crucially on the recording electrode configuration. The integration of an EEG system into cochlear implants paves the way towards chronic neuro-monitoring of hearing-impaired patients in their everyday environment, and neuro-steered hearing prostheses, which can autonomously adjust their output based on neural feedback.
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