Pathogenic Aspergillus Strains Identification and Antifungal Susceptibility Analysis of 452 Cases with Otomycosis in Jingzhou, China

OBJECTIVE

To study the distribution of pathogenic Aspergillus strains of otomycosis in central China and the identification of their antifungal sensitivity.

METHODS

We collected external ear canal secretions clinically diagnosed as otomycosis from April 2020 to January 2023 from the Department of Otolaryngology-Head and Neck Surgery in central China. The pathogenic Aspergillus strains were identified through morphological examination and sequencing. The antifungal sensitivity was performed using the broth microdilution method described in the Clinical Laboratory Standard Institute document M38-A3.

RESULTS

In the 452 clinical strains isolated from the external ear canal, 284 were identified as Aspergillus terreus (62.83%), 92 as Aspergillus flavus (20.35%), 55 as Aspergillus niger (12.17%). In antifungal susceptibility tests the MIC of Aspergillus strains to bifonazole and clotrimazole was high,all the MIC90 is > 16 ug/mL. However, most Aspergillus isolates show moderate greatly against terbinafine, itraconazole and voriconazole.

CONCLUSION

A. terreus is the most common pathogenic Aspergillus strain in otomycosis in central China. The selected topical antifungal drugs were bifonazole and clotrimazole; the drug resistance rate was approximately 30%. If the infection is persistent and requires systemic treatment, terbinafine and itraconazole can be used. The resistance of Aspergillus in otomycosis to voriconazole should be screened to avoid the systemic spread of infection in immunocompromised people and poor compliance with treatment. However, the pan-azole-resistant strain of Aspergillus should be monitored, particularly in high-risk patients with otomycosis.

Patient-derived organoid culture of gastric cancer for disease modeling and drug sensitivity testing

BACKGROUND

Gastric cancer treatment is complicated by the molecular heterogeneity of human tumor cells, which limits the efficacy of standard therapy and necessitates the need for personalized treatment development. Patient-derived organoids (PDOs) are promising preclinical cancer models, exhibiting high clinical efficacy in predicting drug sensitivity, thus providing a new means for personalized precision medicine.

METHODS

PDOs were established from surgically resected gastric cancer tumor tissues. Molecular characterization of the tumor tissues and PDOs was performed using whole-exome sequencing analysis. Drug sensitivity tests were performed by treating the PDO cultures with 21 standard-of-care drugs corresponding to patient treatment. We evaluated whether the PDO drug phenotype reflects the corresponding patient's treatment response by comparing the drug sensitivity test results with clinical data.

RESULTS

Twelve PDOs that satisfied the drug sensitivity test criteria were successfully constructed. PDOs closely recapitulated the pathophysiology and genetic changes in the corresponding tumors, and exhibited different sensitivities to the tested drugs. In one clinical case study, the PDO accurately predicted the patient's sensitivity to capecitabine and oxaliplatin, and in a second case study the PDO successfully predicted the patient's insensitivity to S-1 chemotherapy. In summary, six of the eight cases exhibited consistency between PDO drug susceptibility test results and the clinical response of the matched patient.

CONCLUSIONS

PDO drug sensitivity tests can predict the clinical response of patients with gastric cancer to drugs, and PDOs can therefore be used as a preclinical platform to guide the development of personalized cancer treatment.

Pathogenicity and transcriptome analysis of a strain of Vibrio owensii in Fenneropenaeus merguiensis

Vibrio is an important conditional pathogen in shrimp aquaculture. This research reported a dominant bacteria strain E1 isolated from a shrimp tank with the method of biofloc culture, which was further identified as Vibrio owensii. To understand the interaction between V. owensii and the host shrimp, we studied the pathogenicity of the V. owensii and the molecular mechanisms of the Fenneropenaeus merguiensis immunity during the Vibrio invasion. Drug susceptibility tests showed that V. owensii was resistant to antibiotics streptomycin oxacillin, tetracycline, minocycline, and aztreonam, but highly sensitive to cefazolin, cefotaxime, and ciprofloxacin, and moderately sensitive to cefotaxime, ampicillin, and piperacillin. Lethal concentration 50 (LC₅₀) test was performed to evaluate the toxicity of V. owensii to F. merguiensis. The LC₅₀ of V. owensii infected F. merguiensis after 24, 48, 72, 96, 120, 144 and 168 h were 1.21 × 10⁷, 1.68 × 10⁶, 6.36 × 10⁵, 2.15 × 10⁵, 7.58 × 10⁴, 5.55 × 10⁴ and 4.33 × 10⁴ CFU/mL. In order to explore the molecular response mechanism of F. merguiensis infected with V. owensii, the hepatopancreas of F. merguiensis were sequenced at 24 hpi and 48 hpi, and a total 40,181 of unigenes were obtained. Through comparative transcriptomic analysis, 86 differentially expressed genes (DEGs) (including 38 up-regulated DEGs, and 48 down-regulated DEGs) and 305 DEGs (including 150 up-regulated DEGs, and 155 down-regulated DEGs) were identified at 24 hpi and 48 hpi, respectively. Annotation and classification analysis of these 391 DEGs showed that most of the DEGs were annotated to metableolic and immune pathways, which indicated that F. merguiensis responded to the invasion through the regulation of material metableolism and immune system genes during V. owensii infection. In the KEGG enrichment analysis, some pathways related to immune response were significantly influenced by V. owensii infection, including phagosome, MAPK signalling pathway and PI3K-Akt signalling pathway. In addition, some pathways related to the warburg effect were also significantly enriched after V. owensii infection, including pyruvate metableolism, glycolysis/gluconeogenesis, and citrate cycle (TAC cycle). Further analysis showed that C-type lectins and ficolin were also play important roles in the immune response of F. merguiensis against V. owensii infection. The current research preliminarily revealed the immune response of F. merguiensis to V. owensii infection at the molecular level, which provided valuable information to further understand the disease control and the interaction between shrimp and Vibrio.

Prevalence and molecular characteristics of drug-resistant Mycobacterium tuberculosis in Hainan, China: from 2014 to 2019

Background

The emergence of antimicrobial resistance against Mycobacterium tuberculosis (M. tuberculosis) has become the major concern in global tuberculosis control due to its limited therapy options and high mortality. However, the clinical and molecular characteristics of drug-resistant strains vary in different geographical areas. Hainan Island located in southern China, is a high drug-resistant tuberculosis burden area. This study aimed to determine the dynamic changes of drug-resistance patterns and drug-related gene mutation types of M. tuberculosis in Hainan from 2014 to 2019.

Results

A total of 1484 culture-confirmed M. tuberculosis were included in this study. It was found that the proportions of drug resistance to isoniazid and rifampin were 31.3 and 31.1% respectively. Overall the proportion of multidrug resistant M. tuberculosis was 24.9%. Multivariate logistic regression analysis showed that age and the treatment history were independent influencing factors of drug resistant tuberculosis. The proportions of drug-resistant tuberculosis in retreatment patients were considerably higher than those in new patients. The most common mutation types of isoniazid were Ser315 → Thr (66.3%), and the most common mutation types of rifampin were Ser531 → Leu (41.5%).

Conclusions

Our data suggests that the prevalence of drug resistant TB remains high in Hainan, and the risks for developing drug resistance with diversified mutation types increased significantly in retreatment patients. These results contribute to the knowledge of the prevalence of drug resistance in Hainan Province and expand the molecular characteristics of drug resistance in China simultaneously.

Breast cancer organoids from malignant pleural effusion-derived tumor cells as an individualized medicine platform

Malignant pleural effusion (MPE) presents a severe medical condition in patients with advanced breast cancer (BC). We applied organoid culture technology to culture preoperative puncture specimen and corresponding surgical specimen-derived tumor cells from early BC patients and pleural effusion-derived tumor cells from advanced BC patients with MPE to study whether in vitro models could predict therapies of clinical patients. We successfully expanded pleural effusion-derived tumor organoids from 1 advanced triple-negative breast cancer (TNBC) patient with MPE which had been continuously propagated for more than 3 months. The organoids matched the histological characteristics of primary BC and metastatic supraclavicular lymph nodes by H&E staining and retained negative expression of TNBC biomarkers: estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and positive expression of antigen Ki-67. Multiple mutations were detected from this advanced TNBC patient with MPE by high-throughput sequencing of metastatic supraclavicular lymph node and the plasma sample. We performed the 3D drug screening tests combined with the clinical medication situation of this patient. The pleural effusion-derived tumor organoids were sensitive to capecitabine (IC₅₀ 1.580 μmol) and everolimus (IC₅₀ 4.008 μmol) single-agent treatments. The sensitivity to capecitabine was consistent with the clinical treatment response of this patient for capecitabine and with the sequencing results that reported MTHFR gene polymorphism mutation and TYMS -6bp/-6bp polymorphism mutation indicating effectiveness to fluorouracil. Our results suggested that an effective platform for ex vivo pleural effusion-derived tumor organoids from advanced TNBC patients with MPE could be used to identify treatment options and explore the clinicopathological characteristics of these patients.

Of tuberculosis and non-tuberculous mycobacterial infections - a comparative analysis of epidemiology, diagnosis and treatment

Pulmonary diseases due to mycobacteria cause significant morbidity and mortality to human health. In addition to tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), recent epidemiological studies have shown the emergence of non-tuberculous mycobacteria (NTM) species in causing lung diseases in humans. Although more than 170 NTM species are present in various environmental niches, only a handful, primarily Mycobacterium avium complex and M. abscessus, have been implicated in pulmonary disease. While TB is transmitted through inhalation of aerosol droplets containing Mtb, generated by patients with symptomatic disease, NTM disease is mostly disseminated through aerosols originated from the environment. However, following inhalation, both Mtb and NTM are phagocytosed by alveolar macrophages in the lungs. Subsequently, various immune cells are recruited from the circulation to the site of infection, which leads to granuloma formation. Although the pathophysiology of TB and NTM diseases share several fundamental cellular and molecular events, the host-susceptibility to Mtb and NTM infections are different. Striking differences also exist in the disease presentation between TB and NTM cases. While NTM disease is primarily associated with bronchiectasis, this condition is rarely a predisposing factor for TB. Similarly, in Human Immunodeficiency Virus (HIV)-infected individuals, NTM disease presents as disseminated, extrapulmonary form rather than as a miliary, pulmonary disease, which is seen in Mtb infection. The diagnostic modalities for TB, including molecular diagnosis and drug-susceptibility testing (DST), are more advanced and possess a higher rate of sensitivity and specificity, compared to the tools available for NTM infections. In general, drug-sensitive TB is effectively treated with a standard multi-drug regimen containing well-defined first- and second-line antibiotics. However, the treatment of drug-resistant TB requires the additional, newer class of antibiotics in combination with or without the first and second-line drugs. In contrast, the NTM species display significant heterogeneity in their susceptibility to standard anti-TB drugs. Thus, the treatment for NTM diseases usually involves the use of macrolides and injectable aminoglycosides. Although well-established international guidelines are available, treatment of NTM disease is mostly empirical and not entirely successful. In general, the treatment duration is much longer for NTM diseases, compared to TB, and resection surgery of affected organ(s) is part of treatment for patients with NTM diseases that do not respond to the antibiotics treatment. Here, we discuss the epidemiology, diagnosis, and treatment modalities available for TB and NTM diseases of humans.

[Analysis on drug sensitivity spectrum of 167 multidrug-resistant Mycobacterium tuberculosis in China]

Objective: To investigate the drugs-sensitivity spectrum of multidrug-resistant tuberculosis (MDR-TB) in China and provide a scientific evidence for the drug selection in clinical therapy and the control of MDR-TB. Methods: A total of 167 strains of MDR-TB were included in this study. Every strain was genotyped by lysX gene sequencing and their sensitivity to 13 different anti-TB drugs was tested by using MicroDST(TM) and BACTEC(TM) MGIT 960(TM) liquid-culturing method. The association between drug resistance and genotypes as well as cross drug resistance was also analyzed. The results were analyzed by means of the comparison of enumeration data between two groups with χ(2) test. Results: The overall resistance rate of 167 MDR-TB strains to 11 anti-TB drugs, except isoniazide and rifampicin, was 95.81%, the rates of pre-extensive drug-resistance (pre-XDR) and extensive drug-resistance were 31.14%(52/167) and 6.59% (11/167), respectively. The streptomycin resistance rate of Beijing genotypes was significantly higher than that of the non-Beijing genotypes ( χ(2)=30.682, P<0.05), while the pre-XDR proportion in Beijing genotypes was lower than that in non-Beijing genotypes (χ(2)=5.332, P<0.05). The resistance rates of Ofloxacin and Pyrazinamide in the modern Beijing genotype were significantly higher than those in classical ones (χ(2)=4.105 and χ(2)=3.912, P<0.05). In addition, the cross-resistance rate to rifampicin and rifabutin was 86.23%. A significant difference in drug-resistance rate to rifabutin was seen among groups with different levels of rifampicin resistance (χ(2)=45.912, P<0.05). There was positive correlation not only between ofloxac resistance and moxifloxac resistance, but also between amikacin resistance and kanamycin resistance, with the coefficient of 0.87 and 0.91, respectively. Conclusions: In this study, we observed that there were high incidences of the resistance to 11 anti-TB drugs in 167 clinical MDR-TB strains and the cross resistance phenomena between drugs of the same type were quite serious. The majority of MDR-TB strains belonged to Beijing genotype, which was highly associated with streptomycin resistance.

Breast cancer organoids from a patient with giant papillary carcinoma as a high-fidelity model

Background

Papillary carcinoma is an uncommon type of breast cancer. Additionally, patients with huge breast papillary carcinoma are extremely rare in clinical practice. To improve therapeutic effect on such patients, it is urgent to explore biologically and clinically relevant models of the disease to discover effective drugs.

Methods

We collected surgical tumor specimens from a 63-year-old Chinese woman who has been diagnosed breast papillary carcinoma. The tumor was more than 15 cm in diameter, and applied to establish patient-derived papillary carcinoma organoids that could continuously propagate for more than 6 months.

Results

The papillary carcinoma organoids matched the histological characteristics of orginal tumor by H&E staining identification, and maintained the expression of the breast cancer biomarkers by IHC, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER2) and antigen Ki-67 (Ki67). In addition, we performed a 3-D drug screening to examine the effects of endocrine drugs (Fulvestrant, Tamoxifen) and targeted therapy drugs (Palbociclib, Everolimus, BKM120) on breast papillary carcinoma in the mimic in vivo environment. The drug sensitivities of our breast papillary carcinoma organoids were investigated as follows, Fulvestrant (IC₅₀ 0.275 μmol), Palbociclib (IC₅₀ 2.21 μmol), BKM120 (IC₅₀ 3.81 μmol), Everolimus (IC₅₀ 4.45 μmol), Tamoxifen (IC₅₀ 19.13 μmol).

Conclusions

These results showed that an effective organoid platform for 3-D in vitro culture of breast cancer organoids from patients with breast papillary carcinoma could be used to identify possible treatments, and might be commonly applied to explore clinicopathological characteristics of breast papillary carcinoma.

Timing, distribution, and microbiology of infectious complications after necrotizing pancreatitis

BACKGROUND

Acute pancreatitis (AP) is a common acute abdominal disease worldwide, and its incidence rate has increased annually. Approximately 20% of AP patients develop into necrotizing pancreatitis (NP), and 40% to 70% of NP patients have infectious complications, which usually indicate a worse prognosis. Infection is an important sign of complications in NP patients.

AIM

To investigate the difference in infection time, infection site, and infectious strain in NP patients with infectious complications.

METHODS

The clinical data of AP patients visiting the Department of General Surgery of Xuanwu Hospital of Capital Medical University from January 1, 2014 to December 31, 2018 were collected retrospectively. Enhanced computerized tomography or magnetic resonance imaging findings in patients with NP were included in the study. Statistical analysis of infectious bacteria, infection site, and infection time in NP patients with infectious complications was performed, because knowledge about pathogens and their antibiotic susceptibility patterns is essential for selecting an appropriate antibiotic. In addition, the factors that might influence the prognosis of patients were analyzed.

RESULTS

In this study, 539 strains of pathogenic bacteria were isolated from 162 patients with NP infection, including 212 strains from pancreatic infections and 327 strains from extrapancreatic infections. Gram-negative bacteria were the main infectious species, the most common of which were Escherichia coli and Pseudomonas aeruginosa. The extrapancreatic infection time (9.1 ± 8.8 d) was earlier than the pancreatic infection time (13.9 ± 12.3 d). Among NP patients with early extrapancreatic infection (< 14 d), bacteremia (25.12%) and respiratory tract infection (21.26%) were predominant. Among NP patients with late extrapancreatic infection (> 14 d), bacteremia (15.94%), respiratory tract infection (7.74%), and urinary tract infection (7.71%) were predominant. Drug sensitivity analysis showed that P. aeruginosa was sensitive to enzymatic penicillins, third- and fourth-generation cephalosporins, and carbapenems. Acinetobacter baumannii and Klebsiella pneumoniae were sensitive only to tigecycline; Staphylococcus epidermidis and Enterococcus faecium were highly sensitive to linezolid, tigecycline, and vancomycin.

CONCLUSION

In this study, we identified the timing, the common species, and site of infection in patients with NP.

Collagen gel droplet-embedded culture drug sensitivity test for adjuvant chemotherapy after complete resection of non-small-cell lung cancer. Surg Today. 2018;48:380-387. [PMID: 28993901 DOI: 10.1007/s00595-017-1594-7]

PURPOSE

We conducted a prospective clinical study to individualize adjuvant chemotherapy after complete resection of non-small-cell lung cancer (NSCLC), based on the drug sensitivity test.

METHODS

Patients with resectable c-stage IB-IIIA NSCLC were registered between 2005 and 2010. We performed the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) on a fresh surgical specimen to assess in vitro chemosensitivity and evaluated the prognostic outcome after adjuvant chemotherapy with carboplatin/paclitaxel based on the CD-DST.

RESULTS

Among 92 registered patients, 87 were eligible for inclusion in the analysis. The success rate of CD-DST was 86% and chemosensitivity to carboplatin and/or paclitaxel was evident in 57 (76%) of the 75 patients. Adjuvant chemotherapy was completed in 22 (73%) of 30 patients. The 5-year overall survival rates were 71, 73, and 75% for all, CD-DST success, and chemosensitive patients, respectively. The 5-year disease-free survival and overall survival rates of the chemosensitive patients who completed adjuvant chemotherapy using carboplatin/paclitaxel were 68 and 82%, respectively. The 5-year disease-free survival and overall survival rates of the patients with stage II-IIIA chemosensitive NSCLC were 58 and 75%, respectively. Comparative analyses of the chemosensitive and non-chemosensitive/CD-DST failure groups showed no significant survival difference.

CONCLUSIONS

CD-DST can be used to evaluate chemosensitivity after lung cancer surgery; however, its clinical efficacy for assessing individualized treatment remains uncertain.