Second-generation aryl isonitrile compounds targeting multidrug-resistant Staphylococcus aureus

Antibiotic resistance remains a major global public health threat that requires sustained discovery of novel antibacterial agents with unexploited scaffolds. Structure-activity relationship of the first-generation aryl isonitrile compounds we synthesized led to an initial lead molecule that informed the synthesis of a second-generation of aryl isonitriles. From this new series of 20 compounds, three analogues inhibited growth of methicillin-resistant Staphylococcus aureus (MRSA) (from 1 to 4?µM) and were safe to human keratinocytes. Compound 19, with an additional isonitrile group exhibited improved activity against MRSA compared to the first-generation lead compound. This compound emerged as a candidate worthy of further investigation and further reinforced the importance of the isonitrile functionality in the compounds’ anti-MRSA activity. In a murine skin wound model, 19 significantly reduced the burden of MRSA, similar to the antibiotic fusidic acid. In summary, 19 was identified as a new lead aryl isonitrile compound effective against MRSA.     

Somatic TP53 Mutations Are Detectable in Circulating Tumor DNA from Children with Anaplastic Wilms Tumors

BACKGROUND: Diffuse anaplastic Wilms tumor (DAWT) is a rare, high-risk subtype that is often missed on diagnostic needle biopsy. Somatic mutations in TP53 are associated with the development of anaplasia and with poorer survival, particularly in advanced-stage disease. Early identification of DAWT harboring TP53 abnormalities could improve risk stratification of initial therapy and monitoring for recurrence. METHODS: Droplet digital polymerase chain reaction (ddPCR) was used to evaluate 21 samples from 4 patients with DAWT. For each patient, we assessed TP53 status in frozen tumor, matched germline DNA, and circulating tumor DNA (ctDNA) from plasma, serum, and urine collected throughout treatment. RESULTS: Mutant TP53 was detectable in ctDNA from plasma and serum in all patients. We did not detect variant TP53 in the same volume (200 μl) of urine. One patient displayed heterogeneity of TP53 in the tumor despite both histological sections displaying anaplasia. Concentration of ctDNA from plasma/serum taken prenephrectomy varied significantly between patients, ranging from 0.44 (0.05-0.90) to 125.25 (109.75-140.25) copies/μl. We observed variation in ctDNA throughout treatment, and in all but one patient, ctDNA levels fell significantly following nephrectomy. CONCLUSION: We demonstrate for the first time that ddPCR is an effective method for detection of mutant TP53 in ctDNA from children with DAWT even when there is intratumoral somatic heterogeneity. This should be further explored in a larger cohort of patients, as early detection of circulating variant TP53 may have significant clinical impact on future risk stratification and surveillance.     

Modular design: Implementing proven engineering principles in biotechnology

Modular design is at the foundation of contemporary engineering, enabling rapid, efficient, and reproducible construction and maintenance of complex systems across applications. Remarkably, modularity has recently been discovered as a governing principle in natural biological systems from genes to proteins to complex networks within a cell and organism communities. The convergent knowledge of natural and engineered modular systems provides a key to drive modern biotechnology to address emergent challenges associated with health, food, energy, and the environment. Here, we first present the theory and application of modular design in traditional engineering fields. We then discuss the significance and impact of modular architectures on systems biology and biotechnology. Next, we focus on the very recent theoretical and experimental advances in modular cell engineering that seeks to enable rapid and systematic development of microbial catalysts capable of efficiently synthesizing a large space of useful chemicals. We conclude with an outlook towards theoretical and practical opportunities for a more systematic and effective application of modular cell engineering in biotechnology.     

Salubrinal enhances eIF2α phosphorylation and improves fertility in a mouse model of Classic Galactosemia

Loss of galactose-1 phosphate uridylyltransferase (GALT) activity in humans results in Classic Galactosemia, and the GalT-deficient (GalT^?/?) mouse mimics the patient condition. GalT^?/? ovaries display elevated endoplasmic reticulum (ER) stress marker, BiP, and downregulated canonical phosphatidylinositol 3-kinase (Pi3k)/protein kinase B (Akt) growth/pro-survival signaling. Numbers of primordial follicles are reduced in the mutants, recapitulating the accelerated ovarian aging seen in human patients. We previously found that oral administration of the compound Salubrinal (an eIF2α phosphatase inhibitor), resulted in reduction of ovarian BiP expression, rescued Pi3k/Akt signaling, and a doubling of primordial follicles in GalT^?/? adults. Here, we further characterized galactosemic stress in GalT^?/? mice versus wild-type (WT) controls, and examined whether Salubrinal treatment improved broader reproductive parameters. We assessed the expression levels of factors of the unfolded protein response (UPR), and found that BiP, phospho-Perk, and phospho-eIF2α were all elevated in GalT^?/? ovaries. However, neither IKK activation (NFκB pathway) nor alternative Xbp1 splicing downstream of ER membrane protein Ire1α activation was induced, suggesting an Xbp1-independent UPR in galactosemic stress. Moreover, Salubrinal treatment significantly increased the number of ovulated eggs in mutant animals after gonadotrophic superovulation. Salubrinal treatment also normalized estrus cycle stage lengths and resulted in significantly larger litter sizes than vehicle-treated mutants. Overall, we show that Salubrinal protects against galactosemia-induced primordial follicle loss in a fashion that includes suppressing the de-phosphorylation of eIF2α, and that intervention in this way significantly improves and extends ovarian function, fertility, and fecundity.     

Molecular and cellular bases of diabetes: Focus on type 2 diabetes mouse model-TallyHo

Diabetes is a chronic lifestyle disorder that affects millions of people worldwide. Diabetes is a condition where the body does not produce sufficient insulin or does not use it efficiently. Insulin resistance in diabetes or obesity causes the pancreatic β-cells to increase the insulin output. Diabetes occurs in multiple forms, including type 1, type 2, type 3 and gestational. Type 2 diabetes accounts for ～90–95% of total affected population and is associated with both impaired insulin production by the β-cells of the pancreas and impaired insulin release in response to high blood glucose levels. Diabetes is tightly linked with genetic mutations and genetic and lifestyle activities, including diet and exercise. Recent epidemiological studies established a close link between the diabetes and progression to Alzheimer's disease. This article summarizes various molecular mechanisms involved in the developments of diabetes, including biochemical characteristics, genetic and molecular links with Alzheimer's disease, β-cell function, and factors associated with diabetes. This will help us in the development of novel therapeutic strategies targeting AD in future.     

Distribution and Broadscale Habitat Relations of the Wolverine in the Contiguous United States

ABSTRACT Conservation of the wolverine (Gulo gulo) at the southern extent of its North American range requires reliable understandings of past and present distribution patterns and broad-scale habitat relations. We compiled 820 verifiable and documented records of wolverine occurrence (specimens, DNA detections, photos, and accounts of wolverines being killed or captured) in the contiguous United States from museums, the literature, and institutional archives. We spatially referenced 729 records with areal precision ≤1 township (93.2 km²) and temporal precision ≤10 years. Historical records (1827–1960) were located primarily in the western mountains and Great Lakes region. However, our data suggest that the historical distribution of wolverines in the Cascade Range and Sierra Nevada was disjunct, contradicting previous interpretations. Our results indicate that wolverine range in the contiguous United States had contracted substantially by the mid-1900s. Current records (1995–2005) are limited to north-central Washington, northern and central Idaho, western Montana, and northwestern Wyoming. We investigated potential relations between wolverines and alpine vegetation, cold temperatures, and spring snow cover by comparing the distribution of historical wolverine records with Kuchler's potential natural vegetation types, Holdridge's climatic life zones, and EASE snow-cover maps during the latter portion of the wolverine denning period (15 Apr-14 May). In the western mountains, historical wolverine records generally occurred in or near alpine vegetation and climatic conditions, especially at the limits of their distribution in the Cascade Range, Sierra Nevada, and southern Rocky Mountains. However, the only habitat layer that fully accounted for historical distribution patterns was spring snow cover. Causal factors for the extirpation of wolverines from the southern portions of their range in the contiguous United States are unknown, but are likely related to high levels of human-caused mortality and low to nonexistent immigration rates.     

Phenology and production of Hassaoui grapevines as affected by climate anomalies in Al Ahsa region

Climate change is a dramatic crisis that has left severe impacts on viticulture. Phenological events over 41 years and annual climatic anomalies’ data over these years in Al Ahsa region were procured. Annual temperature and wind speed anomalies had the strongest influence on all phenological events of the varieties White and Red Hassaoui, starting from the beginning of budburst until harvest. Moreover, the average yield of both varieties decreased significantly by 319.4 and 317 kg ha^?1 respectively between 1997 and 2019 in comparison with the interval of years 1979–1996. Earlier phenological events were positively correlated with annual temperature anomaly and negatively correlated with annual wind speed anomaly. The latter shortened the dates of occurrence of beginning and full veraison. Yield decreased with higher annual temperature, wind speed and total cloud cover anomalies, and lower annual total precipitation anomaly. Higher annual temperature and wind speed anomalies were correlated with a shorter period between beginning of budburst to beginning of veraison (P3). Shorter periods between beginning and full veraison (P6) and beginning of veraison and harvest (P7) of Red Hassaoui were positively correlated with annual precipitable water anomaly. Results suggest a high level of adaptation of both tested varieties to changing climate conditions in Al Ahsa, though irrigating vines after harvest on a weekly basis would help overcoming the minimal reduction in yield which was caused by the shortage in precipitation.     

“Lycostrobus” chinleana,an equisetalean cone from the Upper Triassic of the southwestern United States and its phylogenetic implications

Detailed study of the cone Lycostrobus chinleana Daugherty shows that the fossil was incorrectly attributed to the Lycopodiales by the author and to the quillworts by Retallack and that it actually should be assigned to the Equisetales. The cone, which occurs in the Upper Triassic Chinle Formation at several localities in the southwestern United States, is ∼2.5 cm wide and nearly 6 cm long and consists of a stout axis bearing whorls of peltate sporangiophores. Each sporangiophore is composed of a slender stalk and a hexagonal disk, which typically bears a single, generally long, lanceolate, forward-directed leaf-like umbo tip on the outer surface and several recurrent sporangia on the inner surface. Small round to oval trilete spores occur in the sporangia. Since the leaf-like umbo tip is similar to the sterile leaves found in certain calamite cones and the recurrent sporangia are equisetalean-like, it appears that the cone may represent a intermediate stage between Calamites and modern Equisetum. According to this hypothesis, the nonbracteate Equisetum cone could have developed from a bracteate calamite cone, through reduction and fusion of the bracts and the sporangiophores, rather than by the loss of whorls of bracts of the Calamites cone as suggested earlier by others. As a result of this study the cone is assigned to the new Equisetalean genus Equicalastrobus and redescribed under the name E. chinleana (Daugherty) Grauvogel-Stamm and Ash, n. comb.     

A Relational Analysis of American Kinship Terminology

As an alternative to traditional semantic analysis using class-product logic ("Componential analysis"), it is proposed that the possibilities of analysis in terms of relative products be explored in appropriate lexical-taxonomic domains, particularly kinship. In such analyses the order of components is intrinsic to meaning. The process is illustrated by an analysis of American kinship terminology.     

Trends in the perception of ecological problems in the United Nations general debates

To what extent have recent warnings of deepening ecological problems become topics of discussion among international political elites? To address this question a content analysis was undertaken of the speeches comprising the general debates of the 1968, 1972, and 1976 sessions of the UN General Assembly to identify all instances in which ecological issues were mentioned. Despite other indications of an increase in environmental consciousness in the international community, it was found that ecological problems have not been discussed very extensively in the general debates and are far less salient than several other agenda items for which data were also collected. Moreover, the environment peaked as an issue in the 1972 session and declined in prominence in 1976. It was also found that the more developed a country is, the greater the tendency for its delegates to mention environmental problems in their speeches. The lack of prominence of ecological issues is interpreted on the basis of two alternative assumptions: first, that the degree of international awareness of environmental problems is not adequately represented in the general debates and, second, that the findings accurately reflect what is generally a low level of environmental concern in international circles.