Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

BODIPY-Labeled Estrogens for Fluorescence Analysis of Environmental Microbial Degradation

Biodegradation of estrogen hormone micropollutants is a well-established approach toward their remediation. Fluorescently labeled substrates are used extensively for rapid, near-real-time analysis of biological processes and are a potential tool for studying biodegradation processes faster and more efficiently than conventional approaches. However, it is important to understand how the fluorescently tagged surrogates compare with the natural substrate in terms of chemical analysis and the intended application. We derivatized three natural estrogens with BODIPY fluorophores by azide-alkyne cycloaddition click reaction and developed an analytical workflow based on simple liquid-liquid extraction and HPLC-PDA analysis. The developed methods allow for concurrent analysis of both fluorescent and natural estrogens with comparable recovery, accuracy, and precision. We then evaluated the use of BODIPY-labeled estrogens as surrogate substrates for studying biodegradation using a model bacterium for estrogen metabolism. The developed analytical methods were successfully employed to compare the biological transformation of 17β-estradiol (E2), with and without the BODIPY fluorescent tag. Through measuring the complete degradation of E2 and the transformation of BODIPY-estradiol to BODIPY-estrone in the presence of a co-substrate, we found that BODIPY-labeled estrogens are biologically viable surrogates for investigating biodegradation in environmental bacteria.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Rapid, two-pot procedure for the synthesis of dihydropyridinones; total synthesis of aza-goniothalamin

A fast, protecting-group-free synthesis of dihydropyridinones has been developed. Starting from commercially available aldehydes, a novel one-pot amidoallylation gave access to diene compounds in good yields. Ring-closing metathesis conditions were then employed to produce the target dihydropyridinones efficiently and in high yields.

Mutations in the pantothenate kinase of Plasmodium falciparum confer diverse sensitivity profiles to antiplasmodial pantothenate analogues

The malaria-causing blood stage of Plasmodium falciparum requires extracellular pantothenate for proliferation. The parasite converts pantothenate into coenzyme A (CoA) via five enzymes, the first being a pantothenate kinase (PfPanK). Multiple antiplasmodial pantothenate analogues, including pantothenol and CJ-15,801, kill the parasite by targeting CoA biosynthesis/utilisation. Their mechanism of action, however, remains unknown. Here, we show that parasites pressured with pantothenol or CJ-15,801 become resistant to these analogues. Whole-genome sequencing revealed mutations in one of two putative PanK genes (Pfpank1) in each resistant line. These mutations significantly alter PfPanK activity, with two conferring a fitness cost, consistent with Pfpank1 coding for a functional PanK that is essential for normal growth. The mutants exhibit a different sensitivity profile to recently-described, potent, antiplasmodial pantothenate analogues, with one line being hypersensitive. We provide evidence consistent with different pantothenate analogue classes having different mechanisms of action: some inhibit CoA biosynthesis while others inhibit CoA-utilising enzymes.

The coenzyme A (CoA) biosynthetic pathway is under investigation as a target for the development of drugs aimed at several infectious agents, including malaria parasites. To synthesise CoA, the parasite scavenges the essential precursor pantothenate (vitamin B₅). Several pantothenate analogues possess potent (nM) activity against the parasite, but their exact mechanism of action is unknown. We have generated mutant parasites that are resistant or hypersensitive to various pantothenate analogues. These parasites harbour mutations in a gene we now show codes for the first enzyme in the CoA biosynthesis pathway. This enzyme is not the target of the analogues, but instead converts them into antimetabolites that, depending on the analogue, either inhibit a CoA biosynthesis enzyme or downstream CoA-utilising enzymes.

Novel compounds targeting the enterohemorrhagic Escherichia coli type three secretion system reveal insights into mechanisms of secretion inhibition

Anti‐virulence (AV) compounds are a promising alternative to traditional antibiotics for fighting bacterial infections. The Type Three Secretion System (T3SS) is a well‐studied and attractive AV target, given that it is widespread in more than 25 species of Gram‐negative bacteria, including enterohemorrhagic E. coli (EHEC), and as it is essential for host colonization by many pathogens. In this work, we designed, synthesized and tested a new series of compounds that block the functionality of the T3SS of EHEC. Affinity chromatography experiments identified the primary target of the compounds as the T3SS needle pore protein EspD, which is essential for effector protein translocation into host cells. These data were supported by mechanistic studies that determined the coiled‐coil domain 1 of EspD as a key compound‐binding site, thereby preventing correct assembly of the T3SS complex on the cell surface. However, binding of inhibitors to EspD or deletion of EspD itself did not result in transcriptional down‐regulation of effector proteins. Instead, we found the compounds to exhibit dual‐functionality by also down‐regulating transcription of the entire chromosomal locus encoding the T3SS, further demonstrating their desirability and effectiveness.

Advanced stage yolk sac ovarian tumour: clinical approach with cytoreductive surgery upfront

The authors report the case of a 21-year-old woman that presented a Pseudo Meigs' syndrome, secondary to a pure endodermal sinus tumour (yolk sac tumour). Fine needle aspiration biopsy was compatible with high-grade carcinoma and the alpha fetoprotein (αFP) was at 13,185 U/ml. Cytoreductive surgery was performed, followed by bleomycin, etoposide, and cisplatin (BEP) chemotherapy.

Flexible synthesis of polyfunctionalised 3-fluoropyrroles

Convergent synthesis of polyfunctionalised 3-fluoropyrroles.

Short and efficient synthesis of fluorinated δ-lactams

The diastereoselective synthesis of fluorinated δ-lactams.

Convergent approach to complex spirocyclic pyrans: practical synthesis of the oxa-pinnaic acid core

The enantioselective synthesis of the oxa-pinnaic acid framework has been achieved through internal asymmetric induction. The synthetic strategy pursued illustrates the adaptability of the Achmatowicz oxidative rearrangement for the synthesis of complex spirocyclic pyrans starting from tertiary alcohols.

Step-economic synthesis of (+)-crocacin C: a concise crotylboronation/[3,3]-sigmatropic rearrangement approach

The step-economic total synthesis of (+)-crocacin C has been achieved in 20% yield from commercially available starting materials. This approach requires the isolation of only 8 intermediates and can provide a reliable supply of (+)-crocacin C for the development of new antifungal and crop protection agents.

Fast and flexible synthesis of pantothenic acid and CJ-15,801

The fast and efficient syntheses of pantothenic acid and the antiparasitic agent CJ-15,801 have been achieved starting from a common imide unit through the selective manipulation of enamide intermediates.

Aberrant expression of extracellular signal-regulated kinase 5 in human prostate cancer

Abnormal intracellular signaling contributes to carcinogenesis and may represent novel therapeutic targets. mitogen/extracellular signal-regulated kinase kinase-5 (MEK5) overexpression is associated with aggressive prostate cancer. In this study, we examined the role of extracellular signal-regulated kinase (ERK5, an MAPK and specific substrate for MEK5) in prostate cancer. ERK5 immunoreactivity was significantly upregulated in high-grade prostate cancer when compared to benign prostatic hyperplasia (P<0.0001). Increased ERK5 cytoplasmic signals correlated closely with Gleason sum score (P<0.0001), bony metastases (P=0.0044) and locally advanced disease at diagnosis (P=0.0023), with a weak association with shorter disease-specific survival (P=0.036). A subgroup of patients showed strong nuclear ERK5 localization, which correlated with poor disease-specific survival and, on multivariant analysis, was an independent prognostic factor (P<0.0001). Analysis of ERK5 expression in matched tumor pairs (before and after hormone relapse, n=26) revealed ERK5 nuclear expression was significantly associated with hormone-insensitive disease (P=0.0078). Similarly, ERK5 protein expression was increased in an androgen-independent LNCaP subline. We obtained the following in vitro and in vivo evidence to support the above expression data: (1) cotransfection of ERK5wt and MEK5D constructs in PC3 cells results in predominant ERK5 nuclear localization, similar to that observed in aggressive clinical disease; (2) ERK5-overexpressing PC3 cells have enhanced proliferative, migrative and invasive capabilities in vitro (P<0.0001), and were dramatically more efficient in forming tumors, with a shorter mean time for tumors to reach a critical volume of 1000 mm(3), in vivo (P<0.0001); (3) the MEK1 inhibitor, PD184352, blocking ERK1/2 activation at low dose, did not suppress proliferation but did significantly decrease proliferation at a higher dose required to inhibit ERK5 activation. Taken together, our results establish the potential importance of ERK5 in aggressive prostate cancer.

Mechanism of crosstalk inhibition of IL-6 signaling in response to LPS and TNFalpha

Negative regulation of cytokine signaling is critical for the generation of the appropriate cellular outcome in response to signals, and can be modulated by other concomitant extracellular stimuli ("crosstalk"). Using both genetic and pharmacological manipulations we have investigated the mechanisms by which the pro-inflammatory stimuli, lipopolysaccharide (LPS) and Tumor necrosis factor alpha (TNFalpha), negatively regulate interleukin-6 (IL-6) signaling in primary mouse macrophages. Analysis of suppressor of cytokine signalling 3 (SOCS3)-deficient macrophages reveal that SOCS3 is necessary but surprisingly, not sufficient for the complete crosstalk inhibition of IL-6 signaling induced by LPS and TNFalpha. Analysis of macrophages from gp130 (Y757F) mutant mice suggest that SH2 domain-containing tyrosine phosphatase (SHP2) activity does not explain the residual inhibitory effect of these pro-inflammatory stimuli. In addition, p38 mitogen-activated protein kinase (p38) activation also negatively regulates IL-6 signaling independent of its parallel and necessary action to induce SOCS3 expression. Finally, we have identified an additional, novel mechanism of crosstalk inhibition: a reduction in total cellular levels of gp130 following stimulation with LPS and TNFalpha.

VX-680 inhibits Aurora A and Aurora B kinase activity in human cells

VX-680, also known as MK-0457, is a member of a diverse group of small molecules that inhibit the Aurora kinases, and has shown significant potential as an anti-cancer agent. In keeping with many protein kinase inhibitors, this compound is not a monospecific agent, and its cellular specificity remains largely unknown. In cells, VX-680 blocks mitotic Histone H3 phosphorylation and induces polyploidy and apoptosis, consistent with inhibition of the mitotic protein kinase Aurora B. In this study, we have investigated the effects of VX-680 in proliferating human cancer cells, and demonstrate that it blocks the phosphorylation and activation of both Aurora A and B. Additionally, VX-680 suppresses the phosphorylation of specific substrates of each enzyme, including the Aurora A target TACC3 on Ser558. Exposure to VX-680 induces a monopolar spindle phenotype, delays mitotic progression and rapidly overrides the spindle assembly checkpoint in the presence of spindle poisons. VX-680 also exhibits potent cytotoxicity when compared to the well documented Aurora B inhibitor ZM447439. Taken together, these data identify Aurora A and Aurora B as dual intracellular targets of VX-680.

An efficient approach to the stereocontrolled synthesis of enamides

[reaction: see text] A fast, flexible, and efficient approach for the stereocontrolled synthesis of enamides has been developed starting from lactams and amides through the use of imides. This new approach provides access to enamide systems not easily or currently accessible through other approaches.

Enantioselective synthesis of C3 fluoro-MEP

The first enantioselective synthesis of C(3) fluoro-MEP is herein reported. The synthetic pathway developed takes advantage of a selective hydrofluorination of a 2,3-epoxy-1-alcohol to introduce the required tertiary fluoride unit.

New tumor markers: CA125 and beyond

A variety of biomarkers have been developed to monitor growth of ovarian cancer and to detect disease at an early interval. CA125 (MUC16) has provided a useful serum tumor marker for monitoring response to chemotherapy, detecting disease recurrence, distinguishing malignant from benign pelvic masses, and potentially improving clinical trial design. A rapid fall in CA125 during chemotherapy predicts a favorable prognosis and could be used to redistribute patients on multiarmed randomized clinical trials. Several studies now document that CA125 can serve as a surrogate marker for response in phase II trials. Serial measurement of CA125 might also provide a useful marker for monitoring stabilization of disease with cytostatic targeted therapeutic agents. The greatest potential for serum markers may be in detecting ovarian cancer at an early stage. A rising CA125 can be used to trigger transvaginal sonography (TVS) in a small fraction of patients. An algorithm has been developed that calculates risk of ovarian cancer based on serial CA125 values and refers patients at highest risk for TVS. Use of the algorithm is currently being evaluated in a trial with 200,000 women in the UK that will test critically the ability of a two-stage screening strategy to improve survival in ovarian cancer. Whatever the outcome, as 20% of ovarian cancers have little or no expression of CA125, additional serum markers will be required to detect all patients in an initial phase of screening. More than 30 serum markers have been evaluated alone and in combination with CA125 by different investigators. Some of the most promising include: HE4, mesothelin, M-CSF, osteopontin, kallikrein(s), and soluble EGF receptor. Two proteomic approaches have been used: one examines the pattern of peaks on mass spectroscopy and the other uses proteomic analysis to identify a limited number of critical markers that can be assayed by more conventional methods. Both approaches are promising and require further development. Several groups are placing markers on multiplex platforms to permit simultaneous assay of multiple markers with very small volumes of serum. Mathematical techniques are being developed to analyze combinations of marker levels to improve sensitivity and specificity. In the future, serum markers should improve the sensitivity of detecting recurrent disease as well as facilitate earlier detection of ovarian cancer.

Stereocontrolled synthesis of highly functionalised spirocyclic pyrans

Highly functionalized spirocyclic pyrans can be obtained through the Achmatowicz rearrangement of furyl carbinols by taking advantage of the different rates of reaction for epoxidation and nucleophilic addition. Through this methodology, spirocyclic units of various ring sizes can be selectively generated with complete stereocontrol.

New tumor markers: CA125 and beyond

A variety of biomarkers have been developed to monitor growth of ovarian cancer and to detect disease at an early interval. CA125 (MUC16) has provided a useful serum tumor marker for monitoring response to chemotherapy, detecting disease recurrence, distinguishing malignant from benign pelvic masses, and potentially improving clinical trial design. A rapid fall in CA125 during chemotherapy predicts a favorable prognosis and could be used to redistribute patients on multiarmed randomized clinical trials. Several studies now document that CA125 can serve as a surrogate marker for response in phase II trials. Serial measurement of CA125 might also provide a useful marker for monitoring stabilization of disease with cytostatic targeted therapeutic agents. The greatest potential for serum markers may be in detecting ovarian cancer at an early stage. A rising CA125 can be used to trigger transvaginal sonography (TVS) in a small fraction of patients. An algorithm has been developed that calculates risk of ovarian cancer based on serial CA125 values and refers patients at highest risk for TVS. Use of the algorithm is currently being evaluated in a trial with 200,000 women in the UK that will test critically the ability of a two-stage screening strategy to improve survival in ovarian cancer. Whatever the outcome, as 20% of ovarian cancers have little or no expression of CA125, additional serum markers will be required to detect all patients in an initial phase of screening. More than 30 serum markers have been evaluated alone and in combination with CA125 by different investigators. Some of the most promising include: HE4, mesothelin, M-CSF, osteopontin, kallikrein(s), and soluble EGF receptor. Two proteomic approaches have been used: one examines the pattern of peaks on mass spectroscopy and the other uses proteomic analysis to identify a limited number of critical markers that can be assayed by more conventional methods. Both approaches are promising and require further development. Several groups are placing markers on multiplex platforms to permit simultaneous assay of multiple markers with very small volumes of serum. Mathematical techniques are being developed to analyze combinations of marker levels to improve sensitivity and specificity. In the future, serum markers should improve the sensitivity of detecting recurrent disease as well as facilitate earlier detection of ovarian cancer.

The Mnks are novel components in the control of TNF alpha biosynthesis and phosphorylate and regulate hnRNP A1

Posttranscriptional regulatory mechanisms control TNFalpha expression through AU-rich elements in the 3'UTR of its mRNA. This is mediated through Erk and p38 MAP kinase signaling, although the mechanisms involved remain poorly understood. Here, we show that the MAP kinase signal-integrating kinases (Mnks), which are activated by both these pathways, regulate TNFalpha expression in T cells via the 3'UTR. A selective Mnk inhibitor or siRNA-mediated knockdown of Mnk1 inhibits TNFalpha production in T cells, whereas Mnk1 overexpression enhances expression of a reporter construct containing the TNFalpha 3'UTR. We identify ARE binding proteins that are Mnk substrates, such as hnRNP A1, which they phosphorylate at two sites in vitro. hnRNP A1 is phosphorylated in response to T cell activation, and this is blocked by Mnk inhibition. Moreover, Mnk-mediated phosphorylation decreases binding of hnRNP A1 to TNFalpha-ARE in vitro or TNFalpha-mRNA in vivo. Therefore, Mnks are novel players in cytokine regulation and potential new targets for anti-inflammatory therapy.

Synthesis of an IGD peptidomimetic with motogenic activity

Rational design and synthesis of an IGD peptidomimetic substrate with significant motogenic activity.

BCR kinase phosphorylates 14-3-3 Tau on residue 233

The breakpoint cluster region protein, BCR, has protein kinase activity that can auto- and trans-phosphorylate serine, threonine and tyrosine residues. BCR has been implicated in chronic myelogenous leukaemia as well as important signalling pathways, and as such its interaction with 14-3-3 is of major interest. 14-3-3tau and zeta isoforms have been shown previously to be phosphorylated in vitro and in vivo by BCR kinase on serine and threonine residue(s) but site(s) were not determined. Phosphorylation of 14-3-3 isoforms at distinct sites is an important mode of regulation that negatively affects interaction with Raf kinase and Bax, and potentially influences the dimerization of 14-3-3. In this study we have further characterized the BCR-14-3-3 interaction and have identified the site phosphorylated by BCR. We show here that BCR interacts with at least five isoforms of 14-3-3 in vivo and phosphorylates 14-3-3tau on Ser233 and to a lesser extent 14-3-3zeta on Thr233. We have previously shown that these two isoforms are also phosphorylated at this site by casein kinase 1, which, in contrast to BCR, preferentially phosphorylates 14-3-3zeta.

Role that phosphorylation of GSK3 plays in insulin and Wnt signalling defined by knockin analysis

The inactivation of glycogen synthase kinase (GSK)3 has been proposed to play important roles in insulin and Wnt signalling. To define the role that inactivation of GSK3 plays, we generated homozygous knockin mice in which the protein kinase B phosphorylation sites on GSK3alpha (Ser21) and GSK3beta (Ser9) were changed to Ala. The knockin mice were viable and were not diabetic. Using these mice we show that inactivation of GSK3beta rather than GSK3alpha is the major route by which insulin activates muscle glycogen synthase. In contrast, we demonstrate that the activation of muscle glycogen synthase by contraction, the stimulation of muscle glucose uptake by insulin, or the activation of hepatic glycogen synthase by glucose do not require GSK3 phosphorylation on Ser21/Ser9. GSK3 also becomes inhibited in the Wnt-signalling pathway, by a poorly defined mechanism. In GSK3alpha/GSK3beta homozygous knockin cells, Wnt3a induces normal inactivation of GSK3, as judged by the stabilisation of beta-catenin and stimulation of Wnt-dependent transcription. These results establish the function of Ser21/Ser9 phosphorylation in several processes in which GSK3 inactivation has previously been implicated.

Stereocontrolled total synthesis of (-)-callipeltoside A

[structure: see text] A highly stereocontrolled total synthesis of the cytotoxic macrolide (-)-callipeltoside A has been achieved in 23 steps (4.8% overall). Notable features include a novel asymmetric vinylogous aldol reaction to install the C13 stereocenter and (E)-trisubstituted alkene, an anti-selective aldol addition, a Sonogashira coupling, and, last, a Schmidt-type glycosylation to attach the sugar unit.