Toward the Development of a Pan-Lyssavirus Vaccine.

In addition to the rabies virus (RABV), 16 more lyssavirus species have been identified worldwide, causing a disease similar to RABV. Non-rabies-related human deaths have been described, but the number of cases is unknown, and the potential of such lyssaviruses causing human disease is unpredictable. The current rabies vaccine does not protect against divergent lyssaviruses such as Mokola virus (MOKV) or Lagos bat virus (LBV). Thus, a more broad pan-lyssavirus vaccine is needed. Here, we evaluate a novel lyssavirus vaccine with an attenuated RABV vector harboring a chimeric RABV glycoprotein (G) in which the antigenic site I of MOKV replaces the authentic site of rabies virus (RABVG-cAS1). The recombinant vaccine was utilized to immunize mice and analyze the immune response compared to homologous vaccines. Our findings indicate that the vaccine RABVG-cAS1 was immunogenic and induced high antibody titers against both RABVG and MOKVG. Challenge studies with different lyssaviruses showed that replacing a single antigenic site of RABV G with the corresponding site of MOKV G provides a significant improvement over the homologous RABV vaccine and protects against RABV, Irkut virus (IRKV), and MOKV. This strategy of epitope chimerization paves the way towards a pan-lyssavirus vaccine to safely combat the diseases caused by these viruses.

Inhibition of nucleotide biosynthesis disrupts lipid accumulation and adipogenesis.

Energy balance and nutrient availability are key determinants of cellular decisions to remain quiescent, proliferate, or differentiate into a mature cell. After assessing its environmental state, the cell must rewire its metabolism to support distinct cellular outcomes. Mechanistically, how metabolites regulate cell fate decisions is poorly understood. We used adipogenesis as our model system to ascertain the role of metabolism in differentiation. We isolated adipose tissue stromal vascular fraction cells and profiled metabolites before and after adipogenic differentiation to identify metabolic signatures associated with these distinct cellular states. We found that differentiation alters nucleotide accumulation. Furthermore, inhibition of nucleotide biosynthesis prevented lipid storage within adipocytes and downregulated the expression of lipogenic factors. In contrast to proliferating cells, in which mechanistic target of rapamycin complex 1 is activated by purine accumulation, mechanistic target of rapamycin complex 1 signaling was unaffected by purine levels in differentiating adipocytes. Rather, our data indicated that purines regulate transcriptional activators of adipogenesis, peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein α, to promote differentiation. Although de novo nucleotide biosynthesis has mainly been studied in proliferation, our study points to its requirement in adipocyte differentiation.

Hip Abductor Power and Velocity: Reliability and Association With Physical Function.

ABSTRACT: Lanza, MB, Jin, KH, Karl, H, Myers, J, Ryan, E, and Gray, VL. Hip abductor power and velocity: reliability and association with physical function. J Strength Cond Res 37(2): 284-290, 2023-Muscle power, defined as the ability of the muscle to produce torque quickly, has received little attention and may be critical for understanding physical function and performance. Hip abductors' capacity to produce power through both torque and velocity is important for different human activities; hence, a reliable assessment of hip abduction is critical. The first aim of the study was to assess the intersession reliability of hip abductor muscles maximal torque and submaximal power and power during standing hip abduction in young adults using pneumatic resistance. A secondary aim was to investigate whether there was a relationship between hip abductor maximal torque and submaximal power and velocity with clinical assessments of strength and power in young adults. The subjects (n = 24; 26.0 ± 3.7 years) visited the laboratory 2 times. In the first visit, the subjects performed on a pneumatic resistance machine 1-repetition maximum (1RM) and submaximal tests (40, 60, and 70% of 1RM) of the hip abductors and clinical tests of lower-extremity strength and power (The 30-second chair stand test [30CST]; and stair climb power test). During the second visit, all tests were repeated except the clinical tests. One-repetition maximum torque and submaximal power and velocity (at all levels) had excellent reliability (intraclass correlation coefficient ≥ 0.943) with absolute reliability of 13.5% up to 28.3%. The agreement between days from Bland-Altman plots for power and velocity was near 0 for all levels. Hip abduction velocity had a significant positive correlation with 30CST at 60% (r = 0.416; p = 0.048) and 70% of 1RM (r = 0.442; p = 0.035). In conclusion, we showed an excellent intersession reliability of the hip abductor muscles 1RM torque and submaximal power and velocity using pneumatic resistance. Furthermore, we demonstrated that hip abduction velocity might be important for the performance of the 30CST.

Balanced engagement of activating and inhibitory receptors mitigates human NK cell exhaustion.

NK cell exhaustion is caused by chronic exposure to activating stimuli during viral infection, tumorigenesis, and prolonged cytokine treatment. Evidence suggests that exhaustion may play a role in disease progression. However, relative to T cell exhaustion, the mechanisms underlying NK cell exhaustion and methods of reversing it are poorly understood. Here, we describe a potentially novel in vitro model of exhaustion that uses plate-bound agonists of the NK cell activating receptors NKp46 and NKG2D to induce canonical exhaustion phenotypes. In this model, prolonged activation resulted in downregulation of activating receptors, upregulation of checkpoint markers, decreased cytokine production and cytotoxicity in vitro, weakened glycolytic capacity, and decreased persistence, function, and tumor control in vivo. Furthermore, we discovered a beneficial effect of NK cell inhibitory receptor signaling during exhaustion. By simultaneously engaging the inhibitory receptor NKG2A during activation in our model, cytokine production and cytotoxicity defects were mitigated, suggesting that balancing positive and negative signals integrated by effector NK cells can be beneficial for antitumor immunity. Together, these data uncover some of the mechanisms underlying NK cell exhaustion in humans and establish our in vitro model as a valuable tool for studying the processes regulating exhaustion.

Current vaccine strategies against SARS-CoV-2: Promises and challenges.

In the years since the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic began and spread across the globe, lessons have been learned about the challenges and opportunities that a pandemic brings to humankind. Researchers have produced many vaccines at unprecedented speed to protect people, but they have also been cognizant of the challenges presented by a new and unexpected infectious disease. The scope of this review is to examine the path of vaccine discovery so far and identify potential targets. Here, we provide insight into the leading vaccines and their advantages and challenges. We discuss the emerging mutations within the SARS-CoV-2 spike protein and other issues that need to be addressed to overcome coronavirus disease 2019 (COVID-19) completely. Future research is needed to develop a cheap, temperature-stable vaccine providing long-term immunity that protects the upper respiratory tract.

Arsenic Toxicity on Metabolism and Autophagy in Adipose and Muscle Tissues.

Arsenic, a naturally occurring metalloid derived from the environment, has been studied worldwide for its causative effects in various cancers. However, the effects of arsenic toxicity on the development and progression of metabolic syndrome, including obesity and diabetes, has received less attention. Many studies suggest that metabolic dysfunction and autophagy dysregulation of adipose and muscle tissues are closely related to the development of metabolic disease. In the USA, arsenic contamination has been reported in some ground water, soil and grain samples in major agricultural regions, but the effects on adipose and muscle tissue metabolism and autophagy have not been investigated much. Here, we highlight arsenic toxicity according to the species, dose and exposure time and the effects on adipose and muscle tissue metabolism and autophagy. Historically, arsenic was used as both a poison and medicine, depending on the dose and treatment time. In the modern era, arsenic intoxication has significantly increased due to exposure from water, soil and food, which could be a contributing factor in the development and progression of metabolic disease. From this review, a better understanding of the pathogenic mechanisms by which arsenic alters metabolism and autophagy regulation could become a cornerstone leading to the development of therapeutic strategies against arsenic-induced toxicity and metabolic disease.

Limited-Montage EEG as a Tool for the Detection of Nonconvulsive Seizures.

PURPOSE: Prefabricated arrays with a limited number of electrodes offer an opportunity to hasten the diagnosis of seizures; however, their accuracy to detect seizures is unknown. We examined the utility of two limited-montage EEG setups for the detection of nonconvulsive seizures. METHODS: Thirty previously interpreted EEG segments with nonconvulsive seizures from 30 patients and 60 segments with background slowing or normal EEG from 60 patients were rendered in a bipolar "double banana" montage, a double distance "neonatal" montage, and a circumferential "hatband" montage. Experts reviewed 60 to 180 seconds long segments to determine whether seizures were present and if the EEG data provided were sufficient to make a decision on escalation of clinical care by ordering an additional EEG or prescribing anticonvulsants. The periodic patterns on the ictal-interictal continuum were specifically excluded for this analysis to keep the focus on definite electrographic seizures. RESULTS: The sensitivities for seizure of the neonatal and hatband montages were 0.96 and 0.84, respectively, when compared with full montage EEG, whereas the specificities were 0.94 and 0.98, respectively. Appropriate escalation of care was suggested for 96% and 92% of occurrences of seizure patterns in neonatal and hatband montages, respectively. When compared with clinical EEG, the sensitivities of the neonatal and hatband montages for seizure diagnosis were 0.85 and 0.69, respectively. CONCLUSIONS: Nonconvulsive seizures were detected with high accuracy using the limited electrode array configuration in the neonatal and hatband montages. The sensitivity of the neonatal montage EEG in detecting seizures was superior to that of a hatband montage. These findings suggest that in some patients with nonconvulsive seizures, limited-montage EEG may allow to differentiate ictal and slow patterns.

Exploring the NK cell platform for cancer immunotherapy.

Natural killer (NK) cells are cytotoxic lymphocytes of the innate immune system that are capable of killing virally infected and/or cancerous cells. Nearly 20 years ago, NK cell-mediated immunotherapy emerged as a safe and effective treatment approach for patients with advanced-stage leukaemia. Subsequently, the field of NK cell-based cancer therapy has grown exponentially and currently constitutes a major area of immunotherapy innovation. In general, the development of NK cell-directed therapies has two main focal points: optimizing the source of therapeutic NK cells for adoptive transfer and enhancing NK cell cytotoxicity and persistence in vivo. A wide variety of sources of therapeutic NK cells are currently being tested clinically, including haploidentical NK cells, umbilical cord blood NK cells, stem cell-derived NK cells, NK cell lines, adaptive NK cells, cytokine-induced memory-like NK cells and chimeric antigen receptor NK cells. A plethora of methods to augment the cytotoxicity and longevity of NK cells are also under clinical investigation, including cytokine-based agents, NK cell-engager molecules and immune-checkpoint inhibitors. In this Review, we highlight the variety of ways in which diverse NK cell products and their auxiliary therapeutics are being leveraged to target human cancers. We also identify future avenues for NK cell therapy research.

Sestrin2 Phosphorylation by ULK1 Induces Autophagic Degradation of Mitochondria Damaged by Copper-Induced Oxidative Stress.

Selective autolysosomal degradation of damaged mitochondria, also called mitophagy, is an indispensable process for maintaining integrity and homeostasis of mitochondria. One well-established mechanism mediating selective removal of mitochondria under relatively mild mitochondria-depolarizing stress is PINK1-Parkin-mediated or ubiquitin-dependent mitophagy. However, additional mechanisms such as LC3-mediated or ubiquitin-independent mitophagy induction by heavy environmental stress exist and remain poorly understood. The present study unravels a novel role of stress-inducible protein Sestrin2 in degradation of mitochondria damaged by transition metal stress. By utilizing proteomic methods and studies in cell culture and rodent models, we identify autophagy kinase ULK1-mediated phosphorylation sites of Sestrin2 and demonstrate Sestrin2 association with mitochondria adaptor proteins in HEK293 cells. We show that Ser-73 and Ser-254 residues of Sestrin2 are phosphorylated by ULK1, and a pool of Sestrin2 is strongly associated with mitochondrial ATP5A in response to Cu-induced oxidative stress. Subsequently, this interaction promotes association with LC3-coated autolysosomes to induce degradation of mitochondria damaged by Cu-induced ROS. Treatment of cells with antioxidants or a Cu chelator significantly reduces Sestrin2 association with mitochondria. These results highlight the ULK1-Sestrin2 pathway as a novel stress-sensing mechanism that can rapidly induce autophagic degradation of mitochondria under severe heavy metal stress.

Tetracyclines Modify Translation by Targeting Key Human rRNA Substructures.

Apart from their antimicrobial properties, tetracyclines demonstrate clinically validated effects in the amelioration of pathological inflammation and human cancer. Delineation of the target(s) and mechanism(s) responsible for these effects, however, has remained elusive. Here, employing quantitative mass spectrometry-based proteomics, we identified human 80S ribosomes as targets of the tetracyclines Col-3 and doxycycline. We then developed in-cell click selective crosslinking with RNA sequence profiling (icCL-seq) to map binding sites for these tetracyclines on key human rRNA substructures at nucleotide resolution. Importantly, we found that structurally and phenotypically variant tetracycline analogs could chemically discriminate these rRNA binding sites. We also found that tetracyclines both subtly modify human ribosomal translation and selectively activate the cellular integrated stress response (ISR). Together, the data reveal that targeting of specific rRNA substructures, activation of the ISR, and inhibition of translation are correlated with the anti-proliferative properties of tetracyclines in human cancer cell lines.

(1E,2E)-1,2-Bis[(1-benzyloxymethyl-1H-indol-3-yl)methylidene]hydrazine.

The title compound, C(34)H(30)N(4)O(2), lies on an inversion center and consists of two 3-substituted-1H-indole units linked by a 1,2-dimethyl-enehydrazine bridge. It is one of numerous examples in which two aromatic ring systems are joined by this 4-atom bridge. The geometry of the centrosymmetric bridge is: C(arom)-C = 1.444 (3), C=N = 1.284 (3), N-N = 1.414 (4) Å, C(arom)-C=N = 122.6 (2) and C=N-N = 111.9 (2)°. The nine non-H atoms of the indole unit lie in a plane (δ(r.m.s.) = 0.0089 Å) which is twisted 6.0 (2)° with respect to the hydrazine bridge plane. The benzyl-oxymethyl substituents do not lie in the plane of the rest of the mol-ecule and are in a folded rather than an extended conformation. This is described by the three torsion angles in the middle of the C=N-C-O-C(Bz) group, viz. 98.5 (3), -62.1 (3), and -66.3 (2)°.

Effect of inclining strain on the crystal lattice along an extended series of lanthanide hydroxysulfates Ln(OH)SO4 (Ln = Pr-Yb, except Pm).

A series of trivalent lanthanide hydroxysulfates, Ln(OH)SO(4), (Ln = Pr through Yb, except radioactive Pm) has been synthesized via hydrothermal methods from Ln(2)(SO(4))(3)·8H(2)O by reaction with aqueous NaOH at 170 °C in Teflon lined Parr steel autoclaves, and were characterized by single crystal X-ray diffraction and FT-IR spectroscopy. Two types of arrangements were found in the solid state. The lighter (Ln = Pr-Nd, Sm-Gd) and heavier lanthanide(III) hydroxysulfates (Tb-Yb) are each isostructural. Both structure types exhibit the monoclinic space group P2(1)/n, but the unit cell content is doubled with two crystallographically distinct LnO(8) polyhedra for the heavier lanthanide compounds. The lighter complexes maintain the coordination number 9, forming a three-dimensional extended lattice. The heavier counterparts exhibit the coordination number 8, and arrange as infinite columns of two crystallographically different LnO(8) polyhedra, while extending along the "c" axis. These columns of LnO(8) polyhedra are surrounded and separated by six columns of sulfate ions, also elongating in the "c" direction. The rigid sulfate entities seem to obstruct the closing in of the lighter LnO(9) polyhedra, and show an inclining degree of torsion into the "ac" layers. The crystal lattice of the lighter 4f complexes can sufficiently withstand the tension buildup, caused by the decreasing Ln(3+) radius, up to Gd(OH)SO(4). The energy profile of this structural arrangement then seems to exceed levels at which this structure type is favorable. The lattice arrangement of the heavier Ln-analogues seems to offer a lower energy profile. This appears to be the preferred arrangement for the heavier lanthanide hydroxysulfates, whose crystal lattice exhibits more flexibility, as the coordination sphere of these analogues is less crowded. The IR absorbance frequencies of the hydroxide ligands correlate as a function of the Ln(3+) ionic radius. This corresponds well with the X-ray single crystal analysis data.