Transition transferases prime bacterial capsule polymerization.

Capsules are long-chain carbohydrate polymers that envelop the surfaces of many bacteria, protecting them from host immune responses. Capsule biosynthesis enzymes are potential drug targets and valuable biotechnological tools for generating vaccine antigens. Despite their importance, it remains unknown how structurally variable capsule polymers of Gram-negative pathogens are linked to the conserved glycolipid anchoring these virulence factors to the bacterial membrane. Using Actinobacillus pleuropneumoniae as an example, we demonstrate that CpsA and CpsC generate a poly(glycerol-3-phosphate) linker to connect the glycolipid with capsules containing poly(galactosylglycerol-phosphate) backbones. We reconstruct the entire capsule biosynthesis pathway in A. pleuropneumoniae serotypes 3 and 7, solve the X-ray crystal structure of the capsule polymerase CpsD, identify its tetratricopeptide repeat domain as essential for elongating poly(glycerol-3-phosphate) and show that CpsA and CpsC stimulate CpsD to produce longer polymers. We identify the CpsA and CpsC product as a wall teichoic acid homolog, demonstrating similarity between the biosynthesis of Gram-positive wall teichoic acid and Gram-negative capsules.

Factors influencing the outcomes of dermatoses during the COVID-19 outbreak in China: a retrospective study.

Background: The coronavirus disease 2019 (COVID-19) pandemic subverted people's lives and potentially affected the management and prognosis of pre-existing dermatoses. The study aims to identify factors influencing the outcomes of dermatoses during a rapid and widespread Omicron outbreak in China following the adjustment of the COVID-19 policy. Materials and methods: This retrospective observational study involved outpatients visiting the dermatology department at a tertiary referral hospital in Beijing, China between December 2022 and February 2023. Demographics, COVID-19 characteristics, treatment modalities, and dermatosis outcomes were subjected to statistical analysis. Results: The odds ratio (OR) for vitiligo aggravation during COVID-19 was 0.497 [95% confidence interval (CI): 0.254-0.973, p = 0.038] compared to total patients with various dermatoses. Psoriasis patients with a maximum body temperature (Tmax) over 38.6°C during COVID-19 were 2.833 times more likely to experience dermatosis aggravation (OR: 2.833 [1.029-7.803], p = 0.041). Moreover, autoimmune bullous disease (AIBD) patients receiving biologics treatment exhibited a reduced likelihood of aggravation during the COVID-19 outbreak (OR: 0 [0-0.531], p = 0.011). Conclusion: Vitiligo exhibits lower aggravation rates during COVID-19 than other dermatoses. A higher body temperature during COVID-19 infection can increase the risk of psoriasis aggravation. Biologics treatment reduces the risk of AIBD aggravation during the COVID-19 outbreak.

Structure and Ultrafast X-ray Diffraction of the Hydrated Metaphosphate.

We study the pathway of metaphosphate hydration when a metaphosphate anion is dissolved in liquid water with an explicit water model. For this purpose, we propose a sequential Monte Carlo algorithm incorporated with the ab initio quantum mechanics/molecular mechanics (QM/MM) method, which can reduce the amount of ab initio QM/MM sampling while retaining the accuracy of the simulation. We demonstrate the numerical calculation of the standard enthalpy change for the successive addition reaction PO3-·2H2O + H2O ⇌ PO3-·3H2O in the liquid phase, which helps to clarify the hydration pathway of the metaphosphate. With the obtained hydrated structure of the metaphosphate anion, we perform ab initio calculations for its relaxation dynamics upon vibrational excitation and characterize the energy transfer process in solution with simulated ultrafast X-ray diffraction signals, which can be experimentally implemented with X-ray free-electron lasers.

Promoting Photocatalytic Direct C-H Difluoromethylation of Heterocycles using Synergistic Dual-Active-Centered Covalent Organic Frameworks.

Difluoromethylation reactions are increasingly important for the creation of fluorine-containing heterocycles, which are core groups in a diverse range of biologically and pharmacologically active ingredients. Ideally, this typically challenging reaction could be performed photocatalytically under mild conditions. To achieve this separation of redox processes would be required for the efficient generation of difluoromethyl radicals and the reduction of oxygen. A covalent organic framework photocatalytic material was, therefore, designed with dual reactive centers. Here, anthracene was used as a reduction site and benzothiadiazole was used as an oxidation site, distributed in a tristyryl triazine framework. Efficient charge separation was ensured by the superior electron-donating and -accepting abilities of the dual centers, creating long-lived photogenerated electron-hole pairs. Photocatalytic difluoromethylation of 16 compounds with high yields and remarkable functional group tolerance was demonstrated; compounds included bioactive molecules such as xanthine and uracil. The structure-function relationship of the dual-active-center photocatalyst was investigated through electron spin resonance, femtosecond transient absorption spectroscopy, and density functional theory calculations.

Triazine Frameworks for the Photocatalytic Selective Oxidation of Toluene.

Investigations into the selective oxidation of inert sp3 C-H bonds using polymer photocatalysts under mild conditions have been limited. Additionally, the structure-activity relationship of photocatalysts often remains insufficiently explored. Here, a series of thiophene-based covalent triazine frameworks (CTFs) are used for the efficient and selective oxidation of hydrocarbons to aldehydes or ketones under ambient aerobic conditions. Spectroscopic methods conducted in situ and density functional theory (DFT) calculations revealed that the sulfur atoms within the thiophene units play a pivotal role as oxidation sites due to the generation of photogenerated holes. The effect of photogenerated holes on photocatalytic toluene oxidation was investigated by varying the length of the spacer in a CTF donor-acceptor based photocatalyst. Furthermore, the manipulation of reactive oxygen species was employed to enhance selectivity by weakening the peroxidative capacity. As an illustrative example, this study successfully demonstrated the synthesis of a precursor of the neurological drug AMG-579 using a photocatalytic protocol.

Comparison of gut microbiota dysbiosis between pemphigus vulgaris and bullous pemphigoid.

OBJECTIVE: Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are two prevalent bullous diseases. Previous studies found that the antibodies of BP could be expressed in the intestinal epithelium and BP was tightly related to inflammatory bowel disease. Therefore, gut microbiota might also play an important role in bullous disease. However, the specific relationship between gut microbiota and bullous diseases remains unknown. Our study aimed to investigate the potential role of gut microbiota in the development and progression of different bullous diseases. METHODS: We conducted a prospective and observational cohort study at Peking Union Medical College Hospital. Untreated BP and PV patients were recruited, along with healthy controls (HC) who were spouses or caregivers of these patients. Fecal samples were collected, followed by 16S rRNA gene sequencing. Bioinformatics analyses were performed to assess the composition and function of gut microbiota. RESULTS: A total of 38 HC, 32 BP, and 19 PV patients were enrolled in this study. Compared to HC, BP, and PV exhibited a distinct gut microbiota composition, especially BP. The gut microbiota changes were mainly observed in the phylum Bacteroidetes, Firmicutes, and Proteobacteria. The ratio of Faecalibacterium to Escherichia-Shigella (F/E ratio) had a considerable predictive value (AUC: 0.705) for recognizing BP from PV. The levels of Faecalibacterium and Enterobacter were correlated to the anti-BP 180 and anti-desmoglein 3. Microbial functional prediction revealed elevated activity in pathways related to gut microbiota translocation significantly increased in BP patients, indicating a potential pathogenetic role in BP. CONCLUSIONS: Our study suggests that the composition of gut microbiota is specific in different bullous diseases and the role of gut microbiota differs. Gut microbiota could help distinguish BP and PV, and might play a role in the pathogenesis of different bullous diseases.

A highly conserved ligand-binding site for AccA transporters of antibiotic and quorum-sensing regulator in Agrobacterium leads to a different specificity.

Plants genetically modified by the pathogenic Agrobacterium strain C58 synthesize agrocinopines A and B, whereas those modified by the pathogenic strain Bo542 produce agrocinopines C and D. The four agrocinopines (A, B, C and D) serve as nutrients by agrobacteria and signaling molecule for the dissemination of virulence genes. They share the uncommon pyranose-2-phosphate motif, represented by the l-arabinopyranose moiety in agrocinopines A/B and the d-glucopyranose moiety in agrocinopines C/D, also found in the antibiotic agrocin 84. They are imported into agrobacterial cytoplasm via the Acc transport system, including the solute-binding protein AccA coupled to an ABC transporter. We have previously shown that unexpectedly, AccA from strain C58 (AccAC58) recognizes the pyranose-2-phosphate motif present in all four agrocinopines and agrocin 84, meaning that strain C58 is able to import agrocinopines C/D, originating from the competitor strain Bo542. Here, using agrocinopine derivatives and combining crystallography, affinity and stability measurements, modeling, molecular dynamics, in vitro and vivo assays, we show that AccABo542 and AccAC58 behave differently despite 75% sequence identity and a nearly identical ligand binding site. Indeed, strain Bo542 imports only compounds containing the d-glucopyranose-2-phosphate moiety, and with a lower affinity compared with strain C58. This difference in import efficiency makes C58 more competitive than Bo542 in culture media. We can now explain why Agrobacterium/Allorhizobium vitis strain S4 is insensitive to agrocin 84, although its genome contains a conserved Acc transport system. Overall, our work highlights AccA proteins as a case study, for which stability and dynamics drive specificity.

Identification of gut microbiota dysbiosis in bullous pemphigoid under different disease activity.

Bullous pemphigoid (BP) is a severe autoimmune blistering disease affecting patients' quality of life. Gut microbiota (GM) dysbiosis have been investigated to be associated with multiple autoimmune diseases. However, the relationship between GM and BP onset and remission remains to be established by a systematic study. We conducted a study that enrolled 24 patients with BP onset (BP group), 24 patients under remission stage (BP-R group) and 24 healthy controls (HC group). We applied 16S rRNA sequencing on faecal samples and revealed a separation of the microbiota structure. At the family level, Lachnospiraceae, Prevotellaceae and Veillonellaceae were more abundant in the HC and BP-R groups, while Bacteroidaceae, Ruminococcaceae and Enterobacteriaceae were more abundant in the BP group. Bugbase analysis revealed the potentially pathogenic bacteria had an increasing trend in the BP group compared with the HC group and this variation vanished in the BP-R group. At the amplicon sequence variants (ASV) level, Bacteroides ovatus (ASV40) and Veillonella dispar (ASV140) significantly decreased, while Prevotella copri (ASV54) increased in the BP group compared to the HC and BP-R groups. The HC group and BP-R group shared similar abundance. Furthermore, by correlation analysis, we investigated key ASVs correlated with clinical parameters and found some discriminate biomarkers between the BP and BP-R groups. Our study established a dynamic GM profile in BP patients under different disease activity, providing a new direction to understand the role of GM in BP pathogenesis and therapeutic effects.

Anti-interleukin 4 receptor α antibody for the treatment of Chinese bullous pemphigoid patients with diverse comorbidities and a 1-year follow-up: a monocentric real-world study.

Background: Bullous pemphigoid (BP) is a common subepidermal bullous disorder that lacks adequate treatment alternatives. Dupilumab, an anti-interleukin (IL) 4 receptor α antibody blocking Th2 molecules IL-4 and 13, has been used off-label and shown to be effective in refractory BP cases. Methods: BP patients with various disease severities and comorbidities were included in this case series. All patients received dupilumab alone or in combination with immunosuppressants in a real-world setting. Complete remission (CR) was defined as the absence of pruritus symptoms and previous BP eruptions, with only hyperpigmentation patches and without newly occurring lesions for at least 4 weeks. Disease relapse was classified as the appearance of three or more new lesions within 1 month or at least one large urticarial or eczematous lesion that did not resolve within a week. Findings: Ten individuals were enrolled in this case series. Pruritus symptoms and BP eruptions improved significantly in nine patients (90%). Seven patients (70%) attained CR, including all mild-to-moderate (100%) cases and three of six (50%) severe BP cases. At the dupilumab monotherapy stage, eosinophilia was observed in two severe cases. One patient out of seven (14.3%) relapsed after 1 year of follow-up after CR. Conclusion: Treatment of BP with diverse comorbidities with anti-IL-4 receptor α antibody provides further credentials to a prospective randomized study. More impressive efficacy and safety profiles were observed in patients with mild-to-moderate disease after 1 year of follow-up. Eosinophilia may occur in patients receiving dupilumab monotherapy.

Severe acute respiratory syndrome coronavirus 2 infection in patients with autoimmune bullous diseases in China.

Patients with autoimmune bullous diseases (AIBDs) are considered to be immunocompromised and, consequently, they may be more susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and have poorer outcomes. However, the risk and repercussions of SARS-CoV-2 infection in patients with AIBDs have not been fully understood. Therefore, we aimed to investigate the risk factors of SARS-CoV-2 infection and the impact of SARS-CoV-2 on patients with AIBDs. From December 2022 to January 2023, all patients with AIBDs who visited our clinic were enrolled in this study. Meanwhile, web-based questionnaires and telesurveys were used as supplements. Information about patients' demographics, comorbidities, SARS-CoV-2 infection, and vaccination, as well as AIBD status and treatments were collected and analyzed. The diagnosis of SARS-CoV-2 infection was based on a positive polymerase chain reaction test, and/or an antigen test, or the presence of typical symptoms in conjunction with an epidemiological history. Finally, 95 patients with AIBDs were enrolled, including 47 cases of pemphigus and 48 cases of pemphigoid cases, and 73 had symptoms consistent with coronavirus disease 2019. Common symptoms after SARS-CoV-2 infection were fever (80.8%), fatigue (75.0%), cough (71.2%), muscle/joint pain (49.3%), and sore throat (45.2%). No significant differences were found between SARS-CoV-2-infected and asymptomatic patients. Patients who had hypertension (p = 0.034), hyperlipidemia (p = 0.017), or more than two comorbidities (p = 0.011) were more likely to develop pneumonia after infection. Patients with pemphigus who did not achieve disease control (p = 0.045) or had an oral corticosteroid dose ≥15 mg/day (p = 0.024) and patients with pemphigoid with a disease duration ≥2 years (p = 0.037) were more prone to AIBDs aggravation. In conclusion, patients with AIBDs are generally susceptible to SARS-CoV-2 infection. Individuals with newly diagnosed AIBDs, uncontrolled disease, and a higher corticosteroid dose are more susceptible to disease exacerbation.

Selecting resonances in molecular scattering by anti-Zeno effect.

Utilizing the anti-Zeno effect, we demonstrate that the resonances of ultracold molecular interactions can be selectively controlled by modulating the energy levels of molecules with a dynamic magnetic field. We show numerically that the inelastic scattering cross section of the selected isotopic molecules in the mixed isotopic molecular gas can be boosted for 2-3 orders of magnitude by modulation of Zeeman splittings. The mechanism of the resonant anti-Zeno effect in the ultracold scattering is based on matching the spectral modulation function of the magnetic field with the Floquet-engineered resonance of the molecular collision. The resulting insight provides a recipe to implement resonant anti-Zeno effect in control of molecular interactions, such as the selection of reaction channels between molecules involving shape and Feshbach resonances, and external field-assisted separation of isotopes.

Dual Molecular Oxygen Activation Sites on Conjugated Microporous Polymers for Enhanced Photocatalytic Formation of Benzothiazoles.

Oxidative formation of high value compounds involving active oxygen species using heterogeneous polymeric photocatalysts has become a useful tool in catalysis. Controlling the interaction between the active sites on polymer photocatalysts and oxygen molecules is still challenging due to the rather large polymer backbone structure. Here, we design a triazine-containing donor acceptor-type conjugated microporous polymer (CMP) containing dual major active sites at F and N atoms for molecular oxygen activation. Introducing fluorine atoms on the CMP backbone led to a combined effect of enhanced adsorption and electron transfer of oxygen. Time-resolved photoluminescence, electronic paramagnetic resonance spectra, and DFT calculation revealed favorable absorption energy and electron transfer kinetics between the CMP and oxygen molecules, thus efficiently generating superoxide radicals (O2•-) and singlet oxygen (1O2) as main active oxygen species. The photocatalytic activity, selectivity, and reusability of the CMP was demonstrated by the photocatalytic formation of a variety of benzothiazoles.

Expression of Thymic Stromal Lymphopoietin in Immune-Related Dermatoses.

Thymic stromal lymphopoietin (TSLP), long known to be involved in Th2 response, is also implicated in multiple inflammatory dermatoses and cancers. The purpose of this study was to improve our understanding of the expression of TSLP in the skin of those dermatoses. Lesional specimens of representative immune-related dermatoses, including lichen planus (LP), discoid lupus erythematosus (DLE), eczema, bullous pemphigoid (BP), psoriasis vulgaris (PsV), sarcoidosis, and mycosis fungoides (MF), were retrospectively collected and analyzed by immunohistochemistry. Morphologically, TSLP was extensively expressed in the epidermis of each dermatosis, but the expression was weak in specimens of DLE. In a semiquantitative analysis, TSLP was significantly expressed in the epidermis in LP, BP, eczema, PsV, sarcoidosis, and MF. TSLP expression was higher in the stratum spinosum in LP, eczema, BP, PsV, and MF and higher in the stratum basale in sarcoidosis and PsV. Moreover, we found positive TSLP staining in the dermal infiltrating inflammatory cells of BP, PsV, and sarcoidosis. Our observation of TSLP in different inflammatory dermatoses might provide a novel understanding of TSLP in the mechanism of diseases with distinctly different immune response patterns and suggest a potential novel therapeutic target of those diseases.

Tunable Approach to C-Linked Analogs of Glycosamines.

The synthesis of (1R)-2-amino-2-deoxy-ß-l-gulopyranosyl benzene and the α and ß forms of 2-amino-2-deoxy-l-idopyranosyl benzene derivatives was accomplished through stereospecific addition of tributylstannyllithium to readily available (SR)- or (SS)-N-tert-butanesulfinyl-arabinofuranosylamine building blocks, followed by stereoretentive Pd-catalyzed Migita-Kosugi-Stille cross-coupling, stereoselective reduction, and an activation-cyclization strategy. Application of this methodology paves the way to new three-dimensional chemical space and preparation of unknown (non-natural) and complex 2-amino-2-deoxy sugars of biological interest.

Micron channel length ZnO thin film transistors using bilayer electrodes.

Micro light-emitting diodes (Micro-LEDs) are currently attracting more and more attention. Thin film transistors (TFTs) with micron channel lengths can be used to drive Micro-LEDs. The key parameters of TFTs, such as mobility, ION/IOFF and threshold voltage, still need to be improved. In this study, we propose and experimentally demonstrate ZnO TFTs using bilayer electrodes to overcome the short channel effects when the channel length is scaled down to 3 µm. Ti, Mo and Sn interlayers not only serve as diffusion barriers to prohibit migration of Cu atoms from the top electrodes, but also enhance adhesive energy of the metal electrodes on ZnO channel layers. ZnO TFTs using Cu/Ti bilayer electrodes exhibit the best performance, e.g., a high mobility of 45.3 cm2V-1s-1, a high ION/IOFF ratio of 4.28 × 109, a low subthreshold of 0.24 V/dec and a proper threshold voltage of 1.13 V. The high mobility can be attributed to a significant decrease of the barrier height and a slight narrowing of the space charge layer, and the high ratio of ION/IOFF is concerned with the high electron concentration under an ON-state condition. Thus, ZnO TFTs using Cu/Ti bilayer electrodes can be used in next-generation displays.

Coexistence of Anti-p200 Pemphigoid and Psoriasis: A Systematic Review.

Background: A close association between psoriasis and anti-p200 pemphigoid has been demonstrated by numerous studies. However, the clinical characteristics of patients suffering from these two entities have not yet been well-elucidated. Objective: This study aimed to review the case reports and case series, summarizing clinical features and therapeutic strategies in patients suffering from anti-p200 pemphigoid and psoriasis. Methods: A systematic review was conducted by searching PubMed, EMBASE, and Web of Science databases for studies published in English involving patients with psoriasis and anti-p200 pemphigoid on 6 September 2021. All case reports and case series reporting patients diagnosed with anti-p200 pemphigoid and psoriasis were included in this systematic review. Results: A total of 21 eligible studies comprising 26 anti-p200 pemphigoid patients with preceding psoriasis were included in the qualitative synthesis. The average age at blisters eruption was 62.5 years, and the mean duration between the two entities was 15.6 years. Twenty-four percent of patients developed bullous lesions during UV therapy. Clinical manifestation of bullae and/or vesicles was recorded in all patients, and the trunk (94.7%) was most frequently involved, with only 15.8% reporting mucosal involvement. Epitope spreading was detected by immunoblotting in 33.3% of patients. All the patients reached completed remission during the course of disease, with 36.8% experiencing at least one relapse. Monotherapy of prednisolone was the leading therapeutic approach (n=6, 31.6%) required for disease control, but 5 (83.3%) of them suffered from blister recurrence after tapering or ceasing corticosteroid. Conclusion: Most of the clinical aspects of patients with anti-p200 pemphigoid and psoriasis were similar to what was demonstrated in previous articles on anti-p200 pemphigoid. Nevertheless, compared with other anti-p200 pemphigoid cases without psoriasis, a clinical manifestation pattern with more frequent involvement of the trunk and less mucosal involvement was illustrated in those with psoriasis. Generally, monotherapy is sufficient for a complete remission for such patients. However, one or more relapses have been recorded in a considerable portion of patients, especially those prescribed with prednisolone. It reminded us to be more cautious during a tapering of medication.

Efficacy and safety of tetracyclines for pemphigoid: a systematic review and meta-analysis.

The aim of this review was to evaluate the efficacy and safety of tetracyclines for treatment of pemphigoid. We searched PubMed, EMBASE, Ovid, Web of Science, and the Cochrane Library for studies involving pemphigoid patients treated with tetracyclines published in English before 29 February 2020. References of included studies were also screened to widen the scope of the literature search. Data regarding predefined clinical outcomes of 341 patients from 77 studies were extracted and analyzed. A meta-analysis was conducted on the basis of 4 studies including 2 randomized controlled trials and 2 comparative studies. The patients had a mean age of 74.60 ± 13.18 years, 45.4% were males, and 54.6% were females. There were 185 patients with mild-to-moderate and 143 patients with severe disease. The average initial doses were 1.62 ± 0.39 g/day for tetracycline, 0.20 ± 0.01 g/day for doxycycline, and 0.11 ± 0.05 g/day for minocycline. The average time on tetracyclines was 3.74 ± 5.99 months, and 261 (81.3%) patients reported partial or complete remission. Relapses occurred in 72 (28.3%) cases. Adverse effects were experienced by 130 (41.9%) patients. The pooled ORs for short-term effectiveness, relapse, adverse effects, and 1-year survival in patients treated with oral tetracyclines vs. systemic corticosteroids were 0.40 (95% CI, 0.22-0.76), 0.69 (95% CI, 0.44-1.10), 0.47 (95% CI, 0.27-0.82) and 2.02 (95% CI, 1.16-3.50), respectively. Compared to doxycycline and minocycline, tetracycline was significantly associated with better treatment outcomes and fewer adverse effects (p < 0.05). This review revealed tetracyclines' efficacy and safety in pemphigoid treatment and may offer support for clinical use of tetracyclines in pemphigoid.

Case report: Successful treatment of non-bullous lichen planus pemphigoides with dupilumab.

Lichen planus pemphigoides (LPP) is a rare autoimmune bullous disease, characterized by the coexistence of lichen planus and subepidermal bullae. However, the minority of LPP patients present with papules rather than vesicles or blisters, which is defined as non-bullous LPP. The diagnosis of LPP relies on manifestations, histopathology, serological assay, and direct immunofluorescence of linear disposition of IgG and/or C3 at the basement membrane zone. Up to now, no standard therapeutic strategies have been proposed for the treatment of LPP. Herein, we describe an uncommon non-bullous LPP patient with widespread papules and erythema, probably induced by vaccination. During hospitalization, he had a poor response to the conventional treatment of topical and systemic corticosteroids, and his condition was finally alleviated by the addition of dupilumab. For LPP patients with a traditional medication failure, or who were not suitable for a higher dose of corticosteroids, a combination with dupilumab could be an alternative option.

Heterocyclic Chemistry Applied to the Design of N-Acyl Homoserine Lactone Analogues as Bacterial Quorum Sensing Signals Mimics.

N-acyl homoserine lactones (AHLs) are small signaling molecules used by many Gram-negative bacteria for coordinating their behavior as a function of their population density. This process, based on the biosynthesis and the sensing of such molecular signals, and referred to as Quorum Sensing (QS), regulates various gene expressions, including growth, virulence, biofilms formation, and toxin production. Considering the role of QS in bacterial pathogenicity, its modulation appears as a possible complementary approach in antibacterial strategies. Analogues and mimics of AHLs are therefore biologically relevant targets, including several families in which heterocyclic chemistry provides a strategic contribution in the molecular design and the synthetic approach. AHLs consist of three main sections, the homoserine lactone ring, the central amide group, and the side chain, which can vary in length and level of oxygenation. The purpose of this review is to summarize the contribution of heterocyclic chemistry in the design of AHLs analogues, insisting on the way heterocyclic building blocks can serve as replacements of the lactone moiety, as a bioisostere for the amide group, or as an additional pattern appended to the side chain. A few non-AHL-related heterocyclic compounds with AHL-like QS activity are also mentioned.

[Programmed Death-1 Inhibitors-induced Bullous Pemphigoid in 21 Cases].

Objective To investigate the clinical features and treatments of programmed death-1(PD-1)inhibitors-induced bullous pemphigoid(BP).Methods The clinicopathological and immunohistological data of patients with PD-1 inhibitors-induced BP from Peking Union Medical Collage Hospital and reported in the literature were retrospectively analyzed.Results Totally 21 cases(15 males and 6 females)were enrolled.The average age was(70.9±9.7)years(56-86 years).The most common primary malignancies were melanoma(38.10%)and lung cancer(33.33%).The average duration from onset of PD-1 inhibitors treatment to diagnosis of BP was(49.1±23.7)weeks.Typical dermatopathological features were sub-epidermal blisters(76.19%)with infiltration of eosinophils(88.24%).Direct immunofluorescence features were linear deposition of complement C3(95%)and IgG(75%)in the basement membrane zone.Anti-BP180-NC16A antibodies were positive in most cases(84.21%).Patients were mainly treated with systemic corticosteroids,whereas biologics such as rituximab and omazumab were also effective.Conclusions The risk of PD-1 inhibitors-induced BP should be recognized by dermatologists and oncologists.Early diagnosis and timely treatment of BP induced by PD-1 inhibitors are important to improve the prognosis.