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We generated SARS-CoV-2 variants resistant to three SARS-CoV-2 main protease (M pro ) inhibitors (nirmatrelvir, TKB245, and 5h), by propagating the ancestral SARS-CoV-2 WK521 WT in VeroE6 TMPRSS2 cells with increasing concentrations of each inhibitor and examined their structural and virologic profiles. A predominant E166V-carrying variant (SARS-CoV-2 WK521 E166V ), which emerged when passaged with nirmatrelvir and TKB245, proved to be resistant to the two inhibitors. A recombinant SARS-CoV-2 E166V was resistant to nirmatrelvir and TKB245, but sensitive to 5h. X-ray structural study showed that the dimerization of M pro was severely hindered by E166V substitution due to the disruption of the presumed dimerization-initiating Ser1'-Glu166 interactions. TKB245 stayed bound to M pro E166V , whereas nirmatrelvir failed. Native mass spectrometry confirmed that nirmatrelvir and TKB245 promoted the dimerization of M pro , and compromised the enzymatic activity; the Ki values of recombinant M pro E166V for nirmatrelvir and TKB245 were 117±3 and 17.1±1.9 µM, respectively, indicating that TKB245 has a greater (by a factor of 6.8) binding affinity to M pro E166V than nirmatrelvir. SARS-CoV-2 WK521 WT selected with 5h acquired A191T substitution in M pro (SARS-CoV-2 WK521 A191T in the absence of 5h, confirming that A191T confers enhanced viral fitness. The present data should shed light on the understanding of the mechanism of SARS-CoV-2's drug resistance acquisition and the development of resistance-repellant COVID-19 therapeutics.WK521 WT . However, no significant enzymatic or structural changes in M pro A191T were observed. The replicability of SARS-CoV-2 WK521 E166V proved to be compromised compared to SARS-CoV-2 WK521 WT but predominated over SARS-CoV-2 WK521 WT in the presence of nirmatrelvir. The replicability of SARS-CoV-2 WK521 A191T surpassed that of SARS-CoV-2 WK521 WT in the absence of 5h, confirming that A191T confers enhanced viral fitness. The present data should shed light on the understanding of the mechanism of SARS-CoV-2's drug resistance acquisition and the development of resistance-repellant COVID-19 therapeutics., Competing Interests: Competing interests statement:The authors declare no competing interest.

Competing Interests: Disclosures None.

Tigliane diterpenoids possess exceptionally complex structures comprising common 5/7/6/3-membered ABCD-rings and disparate oxygen functionalities. While tiglianes display a wide range of biological activities, compounds with HIV latency-reversing activity can eliminate viral reservoirs, thereby serving as promising leads for new anti-HIV agents. Herein, we report collective total syntheses of phorbol ( 13 ) and 11 tiglianes 14 - 24 with various acylation patterns and oxidation states, and their evaluation as HIV latency-reversing agents. The syntheses were strategically divided into five stages to increase the structural complexity. First, our previously established sequence enabled the expeditious preparation of ABC-tricycle 9 in 15 steps. Second, hydroxylation of 9 and ring-contractive D-ring formation furnished phorbol ( 13 ). Third, site-selective attachment of two acyl groups to 13 produced four phorbol diesters 14 - 17 . Fourth, the oxygen functionalities were regio- and stereoselectively installed to yield five tiglianes 18 - 22 . Fifth, further oxidation to the most densely oxygenated acerifolin A ( 23 ) and tigilanol tiglate ( 24 ) was realized through organizing a 3D shape of the B-ring. Assessment of the HIV latency-reversing activities of the 12 tiglianes revealed seven tiglianes ( 14 - 17 and 22 - 24 ) with 20- to 300-fold improved efficacy compared with prostratin ( 12 ), a representative latency-reversing agent. Therefore, the robust synthetic routes to a variety of tiglianes with promising activities devised in this study provide opportunities for advancing HIV eradication strategies.

Background: A loot box is a gaming term for an electronic lottery that randomly provides items that enhance the gaming experience. In recent years, loot boxes have been increasingly discussed as a risk factor of gaming disorder (GD). While they may be purchased for a few dollars at a time, the cumulative expenses resulting from their addictive use have become a social problem., Case Presentation: This paper presents a case of GD involving a substantial financial burden incurred through the use of a Japanese loot box called Gacha., Conclusion: The randomness in the selection of virtual items in loot boxes resembles gambling, triggering the reward system and contributing to an addiction to purchasing more loot boxes. For therapeutic purposes, understanding the motivations behind purchasing loot boxes and considering individual developmental characteristics are crucial to helping patients find satisfaction and a sense of achievement in activities besides gaming., Competing Interests: Takahiro Nemoto is an Editorial Board member of Psychiatry and Clinical Neurosciences Reports and a co‐author of this article. To minimize bias, he was excluded from all editorial decision‐making related to the acceptance of this article for publication., (© 2024 The Authors. Psychiatry and Clinical Neurosciences Reports published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Psychiatry and Neurology.)

Viruses require host cells to replicate and proliferate, which indicates that viruses hijack the cellular machinery. Human immunodeficiency virus type 1 (HIV-1) primarily infects CD4-positive T cells, and efficiently uses cellular proteins to replicate. Cells already have proteins that inhibit the replication of the foreign HIV-1, but their function is suppressed by viral proteins. Intriguingly, HIV-1 infection also changes the cellular metabolism to aerobic glycolysis. This phenomenon has been interpreted as a cellular response to maintain homeostasis during viral infection, yet HIV-1 efficiently replicates even in this environment. In this review, we discuss the regulatory role of glycolytic enzymes in viral replication and the impact of aerobic glycolysis on viral infection by introducing various host proteins involved in viral replication. Furthermore, we would like to propose a "glyceraldehyde-3-phosphate dehydrogenase-induced shock (G-shock) and kill strategy" that maximizes the antiviral effect of the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH) to eliminate latently HIV-1-infected cells.

The human immunodeficiency virus type 1 (HIV-1) Gag protein is responsible for facilitating HIV-1 virion assembly and budding. Our study demonstrates that cardiolipin (CL), a component found in the inner mitochondrial membrane, exhibits the highest binding affinity to the N-terminal MA domain of the HIV-1 Gag protein within the lipid group of host cells. To assess this binding interaction, we synthesized short acyl chain derivatives of CL and employed surface plasmon resonance (SPR) analysis to determine the dissociation constants (Kd) for CL and the MA domain. Simultaneously, we examined the Kd of D-myo-phosphatidylinositol 4,5-bisphosphate (PI(4,5)P 2 ) derivatives, known to play a crucial role in virion formation. Among all the derivatives, Tetra-C 7 -CL exhibited the lowest Kd value (Kd = 30.8 ± 6.9 μM) for MA binding on the CL analog-immobilized sensorchip, indicating a higher affinity. Similarly, the Kd value of Di-C 7 -PIP2 (Kd = 36.6 ± 4.7 μM) was the lowest on the PI(4,5)P 2 analog-immobilized sensorchip. Thus, Tetra-C 7 -CL binds to the MA domain using a distinct binding mode while displaying a comparable binding affinity to Di-C 7 -PIP2. This discovery holds significant implications for comprehending the virological importance of CL-MA domain binding, such as its subcellular distribution, including mitochondrial translocation, and involvement in viral particle formation in concert with PI(4,5)P 2 . Furthermore, this study has the potential to contribute to the development of drugs in the future., (© 2023 John Wiley & Sons Ltd.)

High-attenuation pulmonary abnormalities are commonly seen on CT. These findings are increasingly encountered with the growing number of CT examinations and the wide availability of thin-slice images. The abnormalities include benign lesions, such as infectious granulomatous diseases and metabolic diseases, and malignant tumors, such as lung cancers and metastatic tumors. Due to the wide spectrum of diseases, the proper diagnosis of high-attenuation abnormalities can be challenging. The assessment of these abnormal findings requires scrutiny, and the treatment is imperative. Our proposed stepwise diagnostic algorithm consists of five steps. Step 1: Establish the presence or absence of metallic artifacts. Step 2: Identify associated nodular or mass-like soft tissue components. Step 3: Establish the presence of solitary or multiple lesions if identified in Step 2. Step 4: Ascertain the predominant distribution in the upper or lower lungs if not identified in Step 2. Step 5: Identify the morphological pattern, such as linear, consolidation, nodular, or micronodular if not identified in Step 4. These five steps to diagnosing high-attenuation abnormalities subdivide the lesions into nine categories. This stepwise radiologic diagnostic approach could help to narrow the differential diagnosis for various pulmonary high-attenuation abnormalities and to achieve a precise diagnosis.Critical relevance statement Our proposed stepwise diagnostic algorithm for high-attenuation pulmonary abnormalities may help to recognize a variety of those high-attenuation findings, to determine whether the associated diseases require further investigation, and to guide appropriate patient management. Key points • To provide a stepwise diagnostic approach to high-attenuation pulmonary abnormalities.• To familiarize radiologists with the varying cause of high-attenuation pulmonary abnormalities.• To recognize which high-attenuation abnormalities require scrutiny and prompt treatment., (© 2023. European Society of Radiology (ESR).)

Amamine (1), a new isoquinoline alkaloid, was isolated from the culture extract of an actinomycete Kitasatospora sp. HGTA304. The structure of 1 was determined by NMR and MS analyses in combination with UV data. Compound 1 displayed α-glucosidase inhibitory potential (IC 50 value of 56 μM) compared with acarbose (IC 50 value of 549 μM) as standard., (© 2023. The Author(s), under exclusive licence to the Japan Antibiotics Research Association.)

Structurally simplified analogues of ansellone A, in which the decalin skeleton is replaced with a lipophilic chain, were prepared and their HIV latency-reversing activities biologically evaluated. In particular, two analogues bearing ether and alkenyl side chains, respectively, showed comparable activities to that of ansellone A. Each of the simplified compounds was easily synthesized using Prins cyclisation chemistry., (© 2023 Wiley-VCH GmbH.)

Nuclear localization signal (NLS) of HIV-1 integrase (IN) is implicated in nuclear import of HIV-1 preintegration complex (PIC). Here, we established a multiclass drug-resistant HIV-1 variant (HIV KGD ) by consecutively exposing an HIV-1 variant to various antiretroviral agents including IN strand transfer inhibitors (INSTIs). HIV KGD was extremely susceptible to a previously reported HIV-1 protease inhibitor, GRL-142, with IC 50 of 130 femtomolar. When cells were exposed to HIV KGD IN-containing recombinant HIV in the presence of GRL-142, significant decrease of unintegrated 2-LTR circular cDNA was observed, suggesting that nuclear import of PIC was severely compromised by GRL-142. X-ray crystallographic analyses revealed that GRL-142 interacts with NLS's putative sequence (DQAEHLK) and sterically blocks the nuclear transport of GRL-142-bound HIV KGD 's PIC. Highly INSTI-resistant HIV-1 variants isolated from heavily INSTI-experienced patients proved to be susceptible to GRL-142, suggesting that NLS-targeting agents would serve as salvage therapy agents for highly INSTI-resistant variant-harboring individuals. The data should offer a new modality to block HIV-1 infectivity and replication and shed light on developing NLS inhibitors for AIDS therapy.

COVID-19 caused by SARS-CoV-2 has continually been serious threat to public health worldwide. While a few anti-SARS-CoV-2 therapeutics are currently available, their antiviral potency is not sufficient. Here, we identify two orally available 4-fluoro-benzothiazole-containing small molecules, TKB245 and TKB248, which specifically inhibit the enzymatic activity of main protease (M pro ) of SARS-CoV-2 and significantly more potently block the infectivity and replication of various SARS-CoV-2 strains than nirmatrelvir, molnupiravir, and ensitrelvir in cell-based assays employing various target cells. Both compounds also block the replication of Delta and Omicron variants in human-ACE2-knocked-in mice. Native mass spectrometric analysis reveals that both compounds bind to dimer M pro , apparently promoting M pro dimerization. X-ray crystallographic analysis shows that both compounds bind to M pro 's active-site cavity, forming a covalent bond with the catalytic amino acid Cys-145 with the 4-fluorine of the benzothiazole moiety pointed to solvent. The data suggest that TKB245 and TKB248 might serve as potential therapeutics for COVID-19 and shed light upon further optimization to develop more potent and safer anti-SARS-CoV-2 therapeutics., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Supramolecular drug carriers are a promising approach for delivering anticancer drugs with high blood retention after administration. We previously synthesized folic acid-modified methyl-β-cyclodextrin (FA-MβCD) as an anticancer drug. FA-MβCD has a selective autophagy-mediated antitumor effect on folic acid receptor (FR)-expressing cancer cells. Here, we enhanced the antitumor effect and safety of FA-MβCD by preparing a supramolecular nanoparticle formulation of FA-MβCD via host-guest interactions using an adamantane conjugate with human serum albumin (Ad-HSA). The Ad-HSA/FA-MβCD supramolecular complex prolonged the blood retention of FA-MβCD and improved its antitumor effect and safety after intravenous administration in tumor-bearing mice xenografted with FR-expressing cancer cells. These results suggest that the supramolecular technique using Ad-HSA is a promising approach for the delivery of CD-based anticancer drugs., (© 2022 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

The first total synthesis of marine sesterterpenoid ansellone G ( 2 ) was accomplished. This strategy utilizes the Prins cyclization reaction of a chloro-substituted homoallyl alcohol to synthesize the hydrobenzopyran skeleton. The preintroduction of the chloro groups facilitated the functional group transformation for 2 after constructing the carbon framework. Furthermore, we also successfully synthesized phorbadione ( 3 ) by dehydrating the tertiary alcohol. The HIV latency-reversing activity of the synthesized 2 , 3 , and deacetylated 2 was also evaluated.

Potent and biostable inhibitors of the main protease (M pro ) of SARS-CoV-2 were designed and synthesized based on an active hit compound 5h ( 2 ). Our strategy was based not only on the introduction of fluorine atoms into the inhibitor molecule for an increase of binding affinity for the pocket of M pro and cell membrane permeability but also on the replacement of the digestible amide bond by a surrogate structure to increase the biostability of the compounds. Compound 3 is highly potent and blocks SARS-CoV-2 infection in vitro without a viral breakthrough. The derivatives, which contain a thioamide surrogate in the P2-P1 amide bond of these compounds ( 2 and 3 ), showed remarkably preferable pharmacokinetics in mice compared with the corresponding parent compounds. These data show that compounds 3 and its biostable derivative 4 are potential drugs for treating COVID-19 and that replacement of the digestible amide bond by its thioamide surrogate structure is an effective method., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)

Background: A single reverse-transcription polymerase chain reaction (RT-PCR) test is not sufficient to exclude COVID-19 in hospital pre-admission screening. However, repeated RT-PCR tests are time-consuming. This study investigates the utility of chest computed tomography (CT) for COVID-19 screening in asymptomatic patients., Methods: Between April 2020 and March 2021, RT-PCR testing and chest CT were performed to screen COVID-19 in 10 823 asymptomatic patients prior to admission. Chest CT findings were retrospectively evaluated using the reporting system of the Radiological Society of North America. Using RT-PCR results as a reference, we assessed the diagnostic efficacy of chest CT during both the low- and high-prevalence periods of the COVID-19 pandemic., Results: Following a positive RT-PCR test, 20 asymptomatic patients (0.18%) were diagnosed with COVID-19; in the low-prevalence period, 5 of 6556 patients (0.076%) were positive; and in the high-prevalence period, 15 of 4267 patients (0.35%) were positive. Of the 20 asymptomatic COVID-19 positive patients, chest CT results were positive for COVID-19 pneumonia in 8 patients. Chest CT results were false-positive in 185 patients (1.7% false-positive rate, and 60% false-negative rate). Pneumonia that was classified as a "typical appearance" of COVID-19 reported as false-positives in 36 of 39 patients (92.3%). Across the study period, the diagnostic efficacy of "typical appearance" on chest CT were characterized by a sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of 15%, 99.7%, 99.7%, 7.7%, and 99.8%; 20%, 99.6%, 99.6%, 4%, and 99.9%; and 13.3%, 99.7%, 99.7%, 14.3%, and 99.7%, in the entire study, low-, and high-prevalence periods, respectively., Conclusions: Addition of chest CT to RT-PCR testing provides no benefit to the detection of COVID-19 in asymptomatic patients., Competing Interests: Conflict of Interest The authors have no conflicts of interest., (Copyright © 2022 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.)

Niemann-Pick disease type C (NPC) is characterized by the accumulation of glycolipids such as free cholesterol, sphingomyelin, and gangliosides in late endosomes/lysosomes (endolysosomes) due to abnormalities in the membrane proteins NPC1 or NPC2. The main symptoms of NPC caused by free cholesterol accumulation in various tissues vary depending on the time of onset, but hepatosplenomegaly and neurological symptoms accompanied by decreased motor, cognitive, and mental functions are observed in all age groups. However, the efficacy of NPC treatment remains limited. Herein, we have fabricated lactose-appended hydroxypropyl-β-cyclodextrin (Lac-HPβCD) and evaluated its lowering effects on cholesterol accumulation in NPC model mice. We reveal that Lac-HPβCD lowers cholesterol accumulation in the liver and spleen by reducing the amount of free cholesterol. Moreover, Lac-HPβCD reduces the amount of free cholesterol in the cerebrum and slightly alleviates motor dysfunction. These results suggest that Lac-HPβCD has potential for the treatment of NPC.

Three new diterpenes, stellejasmins A ( 1 ) and B ( 2 ) and 12- O -benzoylphorbol-13-heptanoate ( 3 ), were isolated from the roots of Stellera chamaejasme L. The structures of 1 - 3 were elucidated by extensive NMR and mass spectroscopic analyses. Compounds 1 and 2 are the first derivatives containing a hydroxy group at C-2 in the family of daphnane and tigliane diterpenes. The presence of a chlorine atom in 1 is unique in the plant metabolite. Compound 3 has an odd-number acyl group, which is biosynthetically notable. Human immunodeficiency virus (HIV) LTR-driven transcription activity was tested with 1 - 3 and 17 known diterpenes isolated from S. chamaejasme L. and Wikstroemia retusa A.Gray. Among these, gnidimacrin ( 4 ), stelleralide A ( 5 ), and wikstroelide A ( 20 ) were highly potent, with EC 50 values of 0.14, 0.33, and 0.39 nM, respectively. The structure-activity relationship (SAR) was investigated using 20 natural and eight synthetic diterpenes. This is the first SAR study on natural daphnane and tigliane diterpenes.