Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma.

AIM: To assess the performance of macular ganglion cell-inner plexiform layer thickness (mGCIPLT) and 10-2 visual field (VF) parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma. METHODS: Totally 127 eyes from 89 participants (36 eyes of 19 healthy participants, 45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients) were included. The relationships between the optical coherence tomography (OCT)-derived parameters and VF sensitivity were determined. Patients with early glaucoma were divided into eyes with or without central 10° of the VF damages (CVFDs), and the diagnostic performances of OCT-derived parameters were assessed. RESULTS: In early glaucoma, the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation (PSD; with average mGCIPLT: ß=-0.046, 95%CI, -0.067 to -0.024, P<0.001). In advanced glaucoma, the mGCIPLT was related to the 24-2 VF mean deviation (MD; with average mGCIPLT: ß=0.397, 95%CI, 0.199 to 0.595, P<0.001), 10-2 VF MD (with average mGCIPLT: ß=0.762, 95%CI, 0.485 to 1.038, P<0.001) and 24-2 VF PSD (with average mGCIPLT: ß=0.244, 95%CI, 0.124 to 0.364, P<0.001). Except for the minimum and superotemporal mGCIPLT, the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs. The area under the curve (AUC) of the average mGCIPLT (AUC=0.949, 95%CI, 0.868 to 0.982) was greater than that of the average circumpapillary retinal nerve fiber layer thickness (cpRNFLT; AUC=0.827, 95%CI, 0.674 to 0.918) and rim area (AUC=0.799, 95%CI, 0.610 to 0.907) in early glaucomatous eyes with CVFDs versus normal eyes. CONCLUSION: The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF, cpRNFLT and ONH parameters, especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

Embosphere microspheres size for bronchial artery embolization in patients with hemoptysis caused by bronchiectasis: a retrospective comparative analysis of 500-750 versus 700-900 µm microspheres.

BACKGROUND: Bronchial arterial embolization (BAE) has been accepted as an effective treatment for bronchiectasis-related hemoptysis. However, rare clinical trials compare different sizes of specific embolic agents. This study aims to evaluate whether different Embosphere microsphere sizes change the outcome of BAE. METHODS: A retrospective review was conducted on consecutive patients with bronchiectatic hemoptysis who were scheduled to undergo BAE treatment during a period from January 2018 to December 2022. The patients received BAE using microspheres of different sizes: group A patients were treated with 500-750 µm microspheres, and group B patients were treated with 700-900 µm microspheres. The cost of embolic microspheres (Chinese Yuan, CNY), duration of hospitalization, complications, and hemoptysis-free survival were compared between patients in group A and those in group B. A Cox proportional hazards regression model was used to identify predictors of recurrent hemoptysis. RESULTS: Median follow-up was 30.2 months (range, 20.3-56.5 months). The final analysis included a total of 112 patients (49-77 years of age; 45 men). The patients were divided into two groups: group A (N = 68), which received 500-750 µm Embosphere microspheres, and group B (N = 44), which received 700-900 µm Embosphere microspheres. Except for the cost of embolic microspheres(group A,5314.8 + 1301.5 CNY; group B, 3644.5 + 1192.3 CNY; p = 0.042), there were no statistically significant differences in duration of hospitalization (group A,7.2 + 1.4 days; group B, 8 + 2.4days; p = 0.550), hemoptysis-free survival (group A, 1-year, 2-year, 3-year, 85.9%, 75.8%, 62.9%; group B, 1-year, 2-year, 3-year, 88.4%, 81.2%,59.4%;P = 0.060), and complications(group A,26.5%; group B, 38.6%; p = 0.175) between the two groups. No major complications were observed. The multivariate analysis results revealed that the presence of cystic bronchiectasis (OR 1.61, 95% CI 1.12-2.83; P = 0.001) and systemic arterial-pulmonary shunts (SPSs) (OR 1.52, 95% CI 1.10-2.72; P = 0.028) were independent risk factors for recurrent bleeding. CONCLUSIONS: For the treatment of BAE in patients with bronchiectasis-related hemoptysis, 500-750 µm diameter Embosphere microspheres have a similar efficacy and safety profile compared to 700-900 µm diameter Embosphere microspheres, especially for those without SPSs or cystic bronchiectasis. Furthermore, the utilization of large-sized (700-900 µm) Embosphere microspheres is associated with the reduced cost of an embolic agent.

Basilic vein variation encountered during surgery for arm vein port: A case report.

BACKGROUND: Venous variations are uncommon and usually hard to identify, and basilic vein variation is particularly rare. Basilic vein variation usually presents without any clinical symptoms and is often regarded as a benign alteration. This case was a patient with congenital basilic vein variation encountered during surgery for an infusion port. CASE SUMMARY: We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port insertion. This peculiarity has hitherto remained undescribed in the literature. We offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its occurrence. We conducted a comprehensive review of analogous cases in the literature, offering pertinent therapeutic recommendations and solutions, with the aim of enhancing the efficacy and safety of future arm port implantations. CONCLUSION: Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy, so as not to affect subsequent treatment.

A pedigree with retinitis pigmentosa and its concomitant ophthalmic diseases.

AIM: To characterize the ophthalmic clinical phenotype of a family with retinitis pigmentosa (RP) and closed-angle glaucoma and to detect pathogenic genes and mutation sites causing RP in this family. METHODS: Ophthalmic clinic performance was examined in detail in 8 enrolled family members. Genomic DNA was extracted from the peripheral blood of 4 family members for whole-exome sequencing (WES) to select potential genetic mutations whose structures were identified by bioinformatics analysis. Then, Sanger sequencing was used in 12 family members and control group members to validate and confirm the disease-causing mutation loci, and we analyzed the genotype-phenotype relationships. RESULTS: The known c.512C>T (p.P171L) mutation in the rhodopsin (RHO) gene was only found in afflicted family members and was confirmed by WES and Sanger sequencing as the pathogenic mutation in this family. In addition to being diagnosed with RP, family member III:4 was found to have bilateral closed-angle glaucoma, high myopia, and concurrent cataracts, and family members II:2 and II:4 had pathological changes of anterior chamber angle narrowing. Family members IV:3 and IV:4 were found to have retinoschisis. CONCLUSION: Glaucoma and related pathological changes, such as retinoschisis, in family members are preliminarily considered RP complications caused by RHO mutation.

Wnt/ß-catenin signalling pathway in breast cancer cells and its effect on reversing tumour drug resistance by alkaloids extracted from traditional Chinese medicine.

Breast cancer is a high-risk disease with a high mortality rate among women. Chemotherapy plays an important role in the treatment of breast cancer. However, chemotherapy eventually results in tumours that are resistant to drugs. In recent years, many studies have revealed that the activation of Wnt/ß-catenin signalling is crucial for the emergence and growth of breast tumours as well as the development of drug resistance. Additionally, drugs that target this pathway can reverse drug resistance in breast cancer therapy. Traditional Chinese medicine has the properties of multi-target and tenderness. Therefore, integrating traditional Chinese medicine and modern medicine into chemotherapy provides a new strategy for reversing the drug resistance of breast tumours. This paper mainly reviews the possible mechanism of Wnt/ß-catenin in promoting the process of breast tumour drug resistance, and the progress of alkaloids extracted from traditional Chinese medicine in the targeting of this pathway in order to reverse the drug resistance of breast cancer.

Comparison of the stability of different concentrations of fluorescein sodium on the detection of tear film rupture time / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the stability of different concentrations of fluorescein sodium solution on the detection of tear break-up time(TBUT).METHODS:A retrospective study. A total of 150 cases(150 eyes)who came to our dry eye clinic with good cooperation from August 2019 to September 2021 were selected for the study, and the subjects were randomly divided into five groups, which were fluorescein sodium(FLS, 0.5%), FLS(1.0%), FLS(1.5%), FLS(2.0%)and fluorescein sodium parallel(FLSP), with 30 patients in each group(all the right eyes were the subject eyes). Each group was dripped with the corresponding fluorescein sodium. The FLSP group was the fluorescent test strip detection group. The slit lamp image scores of different concentration groups were compared, the survival time of sodium fluorescein at the instant, 2, 5, 10, 15 and 30min points was observed in each group, and the mean value of TBUT in each group was recorded.RESULTS: The image score of FLS(0.5%)group was significantly higher than that of the other four groups(t=7.746, 21.483, 116.190, 38.730, all P&#x003C;0.01). The image score of FLS(1.0%)group was significantly higher than that of FLS(1.5%)and FLS(2.0%)group(t=10.742, 15.492, all P&#x003C;0.01). The survival time of fluorescein in FLS(0.5%)group was significantly shorter than that of the other four groups(t=8.226, 7.458, 9.159, 12.347, all P&#x003C;0.01). The survival time of fluorescein in FLS(1.5%)group was significantly longer than that of FLS(1.0%)and FLS(2.0%)group(t=15.428, 13.274, all P&#x003C;0.05). TBUT in FLS(0.5%)group was significantly higher than that of the other four groups at 2min(t=22.767, 22.345, 15.494, 17.213, all P&#x003C;0.01), and was significantly lower than that of the other four groups at 10min(t=23.266, 25.353, 10.183, 22.025, all P&#x003C;0.01). The mean first TBUT of FLS(1.5%)group was significantly shorter than that of the other four groups(t=25.236, 21.374, 19.658, 72.341, all P&#x003C;0.01), and the mean first TBUT of FLSP group was significantly longer than that of the other four groups(t=22.487, 30.267, 60.247, 40.857, all P&#x003C;0.01). There was no significant correlation between TBUT and ocular surface disease index(OSDI)and tear river height(rs=-0.072, 0.219, P=0.689, 0.112). TBUT was positively correlated with tear secretion(rs=0.674, P&#x003C;0.01).CONCLUSION: FLS(0.5%)had higher image quality but it was only suitable for observing staining within 5min, and the FLSP group was more suitable for clinical observation of corneal fluorescence staining for a longer period; FLS(1.5%)was the most stable and reliable concentration and dose for the detection of TBUT.

Microfluid-based soft metasurface for tunable optical activity in THz wave.

Metasurfaces are usually planar structures and do not possess intrinsic chirality and therefore hardly generate optical activity. Here we realized a tunable optical activity in a terahertz wave through a microfluid-based soft metasurface. The meta-atom is a chiral structured microchannel made of soft polydimethylsiloxane and injected with the liquid metal Galinstan. A microfluid pressure system is bonded to the metasurface to reconfigure all meta-atoms simultaneously. By pumping glycerol liquid into the pressure system, the metasurface is deformed from a planar structure to a three dimensional one, which manifests intrinsic chirality for optical activity realization. By controlling the injected glycerol volume, a polarization rotation from 0°to 14° at 0.19 THz is demonstrated. The soft metasurface with tunable optical activity can be flexibly applied in various applications such as polarization microscopy, bio-detection and material analysis, etc.

Synthetic Studies toward Parvistemoline Using Asymmetric Ir/Amine-Catalyzed Allylation.

The common, key tricyclic core of stemona alkaloids parvistemonine (1) and parvistemoline (2), whose synthetic efforts have not reported yet, was constructed through a new strategy in which three contiguous stereogenic centers were set by using Carreira's asymmetric Ir/amine-catalyzed allylation of aldehyde with α-vinylfurfuryl alcohol and Ellman's sulfinamide chiral auxiliary, respectively. The furan ring was especially designed to act as the precursor of the butyrolactone while establishing the significant chirality.

Clinical Effectiveness of Intravenous Peramivir Compared With Oseltamivir in Patients With Severe Influenza A With Primary Viral Pneumonia: A Randomized Controlled Study.

BACKGROUND: High-quality evidence confirms that the clinical efficacy of peramivir in severe influenza patients with primary viral pneumonia is lacking. To optimize clinical medication, we evaluate the different efficacy between peramivir and oseltamivir in the treatment of severe influenza A with primary viral pneumonia. METHODS: A single-center, randomized, controlled trial was conducted during the Chinese influenza season from December 2018 to April 2019 in patients with severe influenza A with primary viral pneumonia. A total of 40 inpatients were enrolled and treated with either intravenous peramivir (300 mg, once daily for 5 days) or oral oseltamivir (75 mg, twice daily for 5 days). RESULTS: The duration of influenza virus nucleic acid positivity in the oseltamivir group and the peramivir group was 2.95 days and 2.80 days, respectively. The remission times of clinical symptoms in the oseltamivir group and the peramivir group were 3.90 days and 3.25 days, respectively. In addition, the remission time of cough symptoms in the peramivir group (63.89 hours) was shorter than that in the oseltamivir group (75.53 hours). There was no significant difference between these values (P > .05). The remission time of fever symptoms in the oseltamivir group was 23.67 hours, which was significantly longer than that in the peramivir group (12.32 hours) (P = .034). CONCLUSIONS: Peramivir is no less effective than oseltamivir in the treatment of severe influenza A with primary viral pneumonia, and patients treated with peramivir had significantly shorter remission times of fever symptoms than those treated with oseltamivir.

Disassembly sequence planning of waste auto parts.

The disassembly of used products is a critical procedure in remanufacturing, and different disassembly strategies are often obtained from different perspectives. To describe the disassembly process more accurately, the uncertainty of the information in the disassembly process should be considered. Therefore, random variables are introduced for disassembly time, cost, and effort. Based on the extended stochastic Petri net modeling method and stochastic programming theory, a stochastic optimization algorithm combined with artificial intelligence technology and a multiobjective genetic algorithm are designed, and a multiobjective optimization model for the disassembly sequence of used car parts under uncertain conditions is successfully constructed. This model considers the viewpoint of the decision maker. Moreover, the Monte Carlo method is applied to solve the multiobjective optimization model, and the validity and practicability of the model are verified by an example of an automotive transmission.Implications: With the rapid development of the economy and the shortening of the product life cycle, the rate of product renewal is getting faster and faster, which also leads to the production of a large number of waste products. According to the forecast of the relevant departments, it is estimated that, in 2020, there will be about 35 million used televisions, 15 million used refrigerators, 13 million used washing machines, 12 million used air conditioners, 57 million used computers, and 8.3 million scrapped cars. Waste products contain a lot of renewable resources. If they cannot be effectively recycled, it will be a great waste of resources, and unreasonable disposal of waste products may have a negative impact on the environment. Therefore, due to environmental pressure and economic drive, product recycling and remanufacturing activities have caused widespread concern in society. Disassembly is defined as the operation or activity of disassembling an assembly such as a product, assembly, or component, and is the result of multiple removal operations of the product. It is a prerequisite for the efficient recycling of products and the first link in remanufacturing, that is, disassembly as a new production activity, which can provide raw materials for the smooth progress of the remanufacturing production plan, namely, old rough or used parts. Efficient dismantling not only saves natural resources and energy, but also effectively reduces environmental pollution. It is also an important guarantee for promoting the healthy development of the circular economy and achieving sustainable industrial development. The length of time required for the dismantling process, the level of costs, and the amount of profits obtained will directly affect the economic benefits of the recycling of end-of-life products. Therefore, the evaluation and optimization of the dismantling process of waste products have become one of the current hot issues. The research on the dismantling of waste products is conducive to speeding up the recycling process of waste, to a greater extent, the rapid and full recovery of resources, and to a certain extent, it will provide value basis and theoretical significance for subsequent research.

Synthesis and biological evaluation of novel isothiazoloquinoline quinone analogues.

Natural quinones and their analogues have attracted growing attention because of their novel anticancer activities. A series of novel isothiazoloquinoline quinone analogues were synthesized and evaluated for antitumor activities against four different kind of cancer cells. Among them, isothiazoloquinolinoquinones inhibited cancer cells proliferation effectively with IC50 values in the nanomolar range, and isothiazoloquinolinoquinone 13a induced the cell apoptosis. Further exploration of possible mechanism of action indicates that 13a not only activates ROS production through NQO1-directed redox cycling but also inhibits the phosphorylation of STAT3. These findings indicate that 13a has potential use for the development of new skeleton drug candidate as an efficient substrate of NQO1 and STAT3 inhibitor.

Percutaneous stent placement for malignant hilar biliary obstruction: side-by-side versus stent-in-stent technique.

BACKGROUND: Currently, side-by-side (SBS) and stent-in-stent (SIS) are the two main techniques for stent deployment to treat hilar biliary obstructions. Previous studies comparing these two techniques are very limited, and thus, no consensus has been reached on which technique is better. The purpose of this study is to compare the clinical efficacy and safety of SBS and SIS deployment via a percutaneous approach for malignant hilar biliary obstruction. METHODS: From July 2012 to April 2019, 65 patients with malignant hilar biliary obstruction who underwent bilateral stenting using either the SBS or SIS techniques were included in this study. Among them, 27 patients underwent SIS stent insertion (SIS group), and the remaining 38 patients underwent SBS stent insertion (SBS group). Technical success, improvement of jaundice, complications, duration of stent patency, and overall survival were evaluated. RESULTS: Technical success was achieved in all patients in the two groups. The serum bilirubin level decreased more rapidly 1 week after the procedures in the SBS group than in the SIS group (P = 0.02). Although the total complication rate did not differ between the two groups, cholangitis was found to be more frequent in the SIS group (P = 0.04). The median stent patency was significantly longer in the SBS group (149 days) than in the SIS group (75 days; P = 0.02). The median overall survival did not significantly differ between the two groups (SBS vs. SIS, 155 days vs. 143 days; P > 0.05). CONCLUSIONS: Percutaneous transhepatic bilateral stenting using either the SBS or SIS technique is safe and effective in the management of malignant hilar biliary obstruction. However, SBS offers a quicker improvement of jaundice, a lower incidence of cholangitis after the procedure, and a longer stent patency period than SIS.

Asymmetric Total Syntheses of (-)-Fennebricin A, (-)-Renieramycin J, (-)-Renieramycin G, (-)-Renieramycin M, and (-)- Jorunnamycin A via C-H Activation.

Collective total synthesis of five tetrahydroisoquinoline alkaloids including the first total synthesis of (-)-fennebricin A and (-)-renieramycin J has been accomplished. The synthesis features employing a single common amino acid to symmetrically construct the pentacycle of title alkaloids. The palladium-catalyzed arylation of alanine-derived amide developed by Yu was tactically utilized to afford unnatural amino acid building block rapidly and practically. The structure of synthetic (-)-renieramycin M has been confirmed by single crystal X-ray analysis for the first time.

A Retrospective Analysis of Three Antiviral Regimens of Peramivir in the Treatment of Severe Influenza A with Primary Viral Pneumonia.

Objective: To evaluate the difference of clinical efficacy of peramivir alone and peramivir combined with immunomodulators (either ribonucleic acid or thymopetidum) in the treatment of severe influenza A with primary viral pneumonia. Methods: A retrospective analysis was applied to 45 patients who were diagnosed with severe influenza A with primary viral pneumonia in our hospital from December 2017 to March 2018. The cases were divided into three groups: the peramivir group, the peramivir combined with ribonucleic acid group, and the peramivir combined with thymopetidum group. Results: The duration of viral nucleic acid positivity in the peramivir group, the peramivir combined with ribonucleic acid group, and the peramivir combined with thymopetidum group was 6.13 ± 2.06, 6.53 ± 2.72, and 6.10 ± 1.37 days, respectively. The remission time of the clinical symptoms of the peramivir group, the peramivir combined with ribonucleic acid group, and the peramivir combined with thymopetidum group was 8.06 ± 2.73, 7.94 ± 2.89, and 7.67 ± 1.58 days, respectively. Comparisons between the peramivir group and the peramivir combined with ribonucleic acid group or the peramivir combined with thymopetidum group revealed no significant differences in the duration of virus nucleic acid positivity, remission time of clinical symptoms, time to fever alleviation, and time to cough alleviation. Conclusions: There is no observed benefit in the addition of ribonucleic acid or thymopetidum when peramivir sodium chloride injection is used in the treatment of severe influenza A with primary viral pneumonia. This trial is registered with ChiCTR1800019417.

Cost-effectiveness analysis of apatinib treatment for chemotherapy-refractory advanced gastric cancer.

BACKGROUND: Apatinib, a third-line or later treatment for advanced gastric cancer (aGC), was shown to improve overall survival and progression-free survival (PFS) compared with placebo in the phase III trial. Given the modest benefit with high costs, we further evaluated the cost-effectiveness of apatinib for patients with chemotherapy-refractory aGC. METHODS: A Markov model was developed to simulate the disease process of aGC (PFS, progressive disease, and death) and estimate the incremental cost-effectiveness ratio (ICER) of apatinib to placebo. The health outcomes and utility scores were derived from the phase III trial and previously published sources, respectively. Total costs were calculated from the perspective of the Chinese health-care payer. Sensitivity analysis was used to explore model uncertainties. RESULTS: Treatment with apatinib was estimated to provide an incremental 0.09 quality-adjusted life years (QALYs) at an incremental cost of $8113.86 compared with placebo, which resulted in an ICER of $90,154.00 per QALY. Sensitivity analysis showed that across the wide variation of parameters, the ICER exceeded the willingness-to-pay threshold of $23,700.00 per QALY which was three times the Gross Domestic Product per Capita in China. CONCLUSIONS: Apatinib is not a cost-effective option for patients with aGC who experienced failure of at least two lines chemotherapy in China. However, for its positive clinical value and subliminal demand, apatinib can provide a new therapeutic option.

FkbN and Tcs7 are pathway-specific regulators of the FK506 biosynthetic gene cluster in Streptomyces tsukubaensis L19.

FK506 (tacrolimus), which is produced by many Streptomyces strains, is clinically used as an immunosuppressive agent and for treatment of inflammatory skin diseases. Here, we identified that the FK506 biosynthetic gene cluster in an industrial FK506-producing strain Streptomyces tsukubaensis L19 is organized as eight transcription units. Two pathway-specific regulators, FkbN and Tcs7, involved in FK506 biosynthesis from S. tsukubaensis L19 were characterized in vivo and in vitro. FkbN activates the transcription of six transcription units in FK506 biosynthetic gene cluster, and Tcs7 activates the transcription of fkbN. In addition, the DNA-binding specificity of FkbN was determined. Finally, a high FK506-producing strain was constructed by overexpression of both fkbN and tcs7 in S. tsukubaensis L19, which improved FK506 production by 89 % compared to the parental strain.

Functions of Type II Thioesterases in Bacterial Polyketide Biosynthesis.

Many polyketides show biological activities and have thus been applied in clinics, as food additives, and in agriculture. Type II thioesterases (TEIIs) play an important role in polyketide biosynthesis. Most TEIIs belong to α/ß-hydrolase family and usually contain a catalytic triad Ser-His-Asp. In polyketide biosynthesis, TEIIs can play an editing role by removal of aberrant non-extendable acyl units in elongation steps, a starter unit selection role by removal of unfavored starter acyl units in initiation steps, and a releasing role by removal of final product in termination steps. Complementation of TEIIs has been observed and applied.

Characterization of Discrete Phosphopantetheinyl Transferases in Streptomyces tsukubaensis L19 Unveils a Complicate Phosphopantetheinylation Network.

Phosphopantetheinyl transferases (PPTases) play essential roles in both primary metabolisms and secondary metabolisms via post-translational modification of acyl carrier proteins (ACPs) and peptidyl carrier proteins (PCPs). In this study, an industrial FK506 producing strain Streptomyces tsukubaensis L19, together with Streptomyces avermitilis, was identified to contain the highest number (five) of discrete PPTases known among any species thus far examined. Characterization of the five PPTases in S. tsukubaensis L19 unveiled that stw ACP, an ACP in a type II PKS, was phosphopantetheinylated by three PPTases FKPPT1, FKPPT3, and FKACPS; sts FAS ACP, the ACP in fatty acid synthase (FAS), was phosphopantetheinylated by three PPTases FKPPT2, FKPPT3, and FKACPS; TcsA-ACP, an ACP involved in FK506 biosynthesis, was phosphopantetheinylated by two PPTases FKPPT3 and FKACPS; FkbP-PCP, an PCP involved in FK506 biosynthesis, was phosphopantetheinylated by all of these five PPTases FKPPT1-4 and FKACPS. Our results here indicate that the functions of these PPTases complement each other for ACPs/PCPs substrates, suggesting a complicate phosphopantetheinylation network in S. tsukubaensis L19. Engineering of these PPTases in S. tsukubaensis L19 resulted in a mutant strain that can improve FK506 production.