[First report of invasive Pomacea snails in Shandong Province]

OBJECTIVE

To characterize the species of invasive Pomacea snails that were discovered for the first time in Shandong Province.

METHODS

Pomacea snails samples were collected in the field of Jining City, Shandong Province on October 2021 for morphological identification. Pomacea snails were randomly sampled and genomic DNA was extracted from foot muscle tissues of Pomacea snails for multiplex PCR amplification. The PCR amplification product was sequenced. Then, the sequence was aligned and a phylogenetic tree was created using the software MegAlign 7.1.0. In addition, Angiostongylus cantonensis infection was detected in Pomacea snails with the lung microscopy.

RESULTS

A total of 104 living Pomacea snails were collected, and all were characterized as Pomacea spp. based on morphological features. Of 12 randomly selected adult Pomacea snails, multiplex PCR assay and sequencing identified eleven snails as P. canaliculata and one as P. maculata. No A. cantonensis infection was detected in 104 Pomacea snails.

CONCLUSIONS

This is the first report of invasive Pomacea snails in Shandong Province, where P. canaliculata and P. maculata are found.

[Clinical and imaging features of Chlamydia psittaci pneumonia: an analysis of 48 cases in China]

Objective: To explore the clinical characteristics, imaging findings, laboratory tests and treatment strategies for Chlamydia psittaci pneumonia. Methods: From January 1, 2019 to January 20, 2021, 48 cases of Psittacosis from 11 hospitals in China were diagnosed via metagenomic next-generation sequencing(mNGS). The data of all patients on occupational history, clinical manifestations, laboratory tests, chest computed tomography(CT)findings, treatment outcomes and prognosis were retrospectively analyzed. Results: Among the 48 patients, there were 29 males and 19 females, with a mean age of (57.1±10.3) years. Thirty patients had a confirmed history of exposure to poultry. The onset to admission interval was (6.5±3.2) days, and hospital stay was (12.4±4.8) days. Clinical manifestations included fever (100%, 48/48), relative bradycardia (71%, 34/48), cough (54.2%, 26/48), sputum (27.1%, 13/48), fatigue (16.7%, 8/48), headache and delirium (20.8%, 9/48), and gastrointestinal symptoms (16.7%, 8/48). Laboratory data showed that white blood cells were (8.0±3.8)×10⁹/L, and the proportion of neutrophils increased in 44 patients. The level of C-reactive protein was (155.3±74.1)mg/L, and that of procalcitonin (PCT)in 59.5% of patients was more than 0.5 μg/L. Percentages of patients with increased lactate dehydrogenase and creatine kinase were 82.9% and 45.2%, respectively. Chest CT scans showed unilateral lung involvement in 34 cases(70.8%) and single lobe involvement in 27 cases(56.3%).The most common imaging change was consolidation, with 38 cases (79.2%) showing lobar consolidation. In terms of treatment, 25 patients were treated with fluoroquinolones alone, 6 patients with doxycycline alone, and 13 patients with combined treatment. The combined-treatment group and the doxycycline alone group were similar in the course of defervescence. The combined treatment group and the doxycycline alone group were both superior to the fluoroquinolones alone group. However, 11 patients were admitted to ICU, all of them received artificial ventilation, and 5 cases developed shock, and one died. Conclusions: Chlamydia psittaci pneumonia is an animal-derived infectious disease with unique features in clinical symptoms, laboratory tests and chest imaging. Appropriate treatment is able to significantly shorten the course of disease and improve the prognosis.

[Surveillance of Enterobius vermicularis infections among children in Shandong Province from 2016 to 2020]

OBJECTIVE

To investigate the prevalence and changing trend of Enterobius vermicularis infections among children in Shandong Province, so as to provide the scientific evidence for the adjustment and development of the enterobiasis control strategy.

METHODS

Soil-borne nematodiasis surveillance sites were assigned in 51 counties (districts, cities) in Shandong Province from 2016 to 2020, and the E. vermicularis infections were detected using a modified Kato-Katz technique and the cellophane tape method among children at ages of 3 to 9 years living in these surveillance sites. The epidemiological profiles of E. vermicularis-infected children were descriptively analyzed.

RESULTS

A total of 5 060 children at ages of 3 to 9 years were detected in 51 soil-borne nematodiasis surveillance sites in Shandong Province from 2016 to 2020, and the overall prevalence of E. vermicularis infections was 2.23%. The annual prevalence of E. vermicularis infections was 3.99% (26/651), 1.70% (14/824), 0.96% (8/837), 2.90% (45/1 552) and 1.67% (20/1 196) from 2016 to 2020, respectively, with a significant difference detected among years (χ² = 21.455, P < 0.01). The prevalence of E. vermicularis infections was 1.25% (15/1 198), 1.85% (14/755), 3.18% (84/2 640) and 0 (0/467) among children from central, eastern, southern and northern Shandong Province (χ² = 27.326, P < 0.01). In addition, there was no significant difference in the prevalence of E. vermicularis infections between male (1.98%, 56/2 831) and female children (2.56%, 57/2 229) (χ² = 1.916, P > 0.05); however, there was age-specific prevalence of E. vermicularis infections among children (χ² = 16.448, P < 0.05), with the greatest prevalence detected among children at ages of 6 years (3.18%, 25/786), and the lowest prevalence seen among children at ages of 3 years (0.75%, 6/800).

CONCLUSIONS

The prevalence of E. vermicularis infections remained at a medium level among children at ages of 3 to 9 years in Shandong Province from 2016 to 2020, with region-specific prevalence found across the province. An integrated strategy is required for enterobiasis control.

[Epidemiological characteristics of imported malaria in Shandong province, 2017-2018]

Objective: To understand epidemiological characteristics of imported cases of malaria in Shandong province and provide scientific basis for timely adjustment of prevention and control measures. Methods: The incidence data of malaria, case investigation data and case review data by Shandong Provincial Reference Laboratory for Malaria Diagnosis from 2017 to 2018 were collected. Software SPSS 18.0 was used for statistical analysis and software QGIS 2.18 was used for mapping. Results: A total of 442 imported cases of malaria were reported in Shandong from 2017 to 2018, and the main infection source was in Africa (97.96%, 433/442). All the 17 prefectures in Shandong reported imported malaria cases, mainly in Jining (88 cases), Yantai (65 cases), Weihai (46 cases), Qingdao (44 cases) and Dezhou (42 cases), accounting for 64.48% (285/442). The cases were distributed in 77.37%(106/137) of counties of the province. The cases were reported in every month without seasonal characteristics. The median (M) of time interval between onset and the first medical care seeking was 2 days, and the interquartile range (IQR) was 3 days. The M of time interval between the first medical care seeking and final diagnosis was 0 day, and the IQR was 3 days. The proportion of medical care seeking on onset day was only 27.83% (123/442). Only 69.68% (308/442) of cases were diagnosed with malaria in the first medical care seeking, and the diagnostic accuracy of medical institutions below the county level was lower than other medical institutions (all P<0.01). Only 51.13% (226/442) of cases were diagnosed with malaria in the first medical care seeking, the differences in the rates among medical institutions at different levels were not significant (P>0.05). Conclusions: The imported malaria in Shandong was characterized by a large number of cases, multiple infection sources and wide area distribution during 2017-2018. The awareness of timely medical care seeking in the cases was low, meanwhile the awareness and ability of malaria diagnosis and treatment in primary medical institutions were still inadequate. It is necessary to adjust the prevention and control measures accordingly.

[Analysis of drug - resistant gene polymorphisms in Plasmodium falciparum imported from Equatorial Guinea to Shandong Province in 2015 and 2016]

OBJECTIVE

To investigate the drug-resistant gene polymorphisms in Plasmodium falciparum imported from Equatorial Guinea to Shandong Province.

METHODS

From 2015 to 2016, blood samples were collected from imported P. falciparum malaria patients returning from Equatorial Guinea to Shandong Province, and genome DNA of the malaria parasite was extracted. The drug-resistant Pfcrt, Pfmdr1, Pfdhfr, Pfdhps, and K13 genes of P. falciparum were amplified using a PCR assay, followed by DNA sequencing, and the sequences were aligned.

RESULTS

The target fragments of all 5 drug-resistant genes of P. falciparum were successfully amplified and sequenced. There were 72.8%, 18.6%, and 8.6% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfcrt gene, respectively, and all mutant haplotypes were CVIET (the underline indicates the mutation site). There were 20.0%, 61.4% and 18.6% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfmdr1 gene, respectively, and the mutant haplotypes mainly included YF and NF (the underlines indicate the mutation sites). There were 1.4%, 98.6%, and 0 of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfdhfr gene, respectively, and AIRNI was the predominant mutant haplotype (the underline indicates the mutation site). There were 1.4%, 94.3%, and 4.3% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfdhps gene, respectively, and SGKAA was the predominant mutant haplotype (the underline indicates the mutation site). The complete drug-resistant IRNGE genotype consisted of 8.6% of the Pfdhfr and Pfdhps genes, and the K13 gene A578S mutation occurred in 1.4% of the parasite samples.

CONCLUSIONS

There are mutations in the Pfcrt, Pfmdr1, Pfdhfr, Pfdhps, and K13 genes of P. falciparum imported from Equatorial Guinea to Shandong Province, with a low frequency in the Pfcrt gene mutation and a high frequency in the Pfmdr1, Pfdhfr, and Pfdhps gene mutations, and the K13 gene A578S mutation is detected in the parasite samples.

Radiofrequency ablation for hepatic hemangiomas: A consensus from a Chinese panel of experts

Recent studies have shown that radiofrequency (RF) ablation therapy is a safe, feasible, and effective procedure for hepatic hemangiomas, even huge hepatic hemangiomas. RF ablation has the following advantages in the treatment of hepatic hemangiomas: minimal invasiveness, definite efficacy, high safety, fast recovery, relatively simple operation, and wide applicability. It is necessary to formulate a widely accepted consensus among the experts in China who have extensive expertise and experience in the treatment of hepatic hemangiomas using RF ablation, which is important to standardize the application of RF ablation for the management of hepatic hemangiomas, regarding the selection of patients with suitable indications to receive RF ablation treatment, the technical details of the techniques, therapeutic effect evaluations, management of complications, etc. A final consensus by a Chinese panel of experts who have the expertise of using RF ablation to treat hepatic hemangiomas was reached by means of literature review, comprehensive discussion, and draft approval.

Polymorphic microsatellite loci isolated from the yellowbelly threadfin bream, Nemipterus bathybius

Twenty-two polymorphic microsatellite loci were isolated and characterized from a (GT)13-enriched Nemipterus bathybius genomic library. The number of alleles per locus ranged from 4 to 13, with an average of 7.86. The observed and expected heterozygosity was 0.167-0.889 and 0.278-0.904, respectively, with averages of 0.590 and 0.690. Three loci deviated from Hardy-Weinberg proportions, and 2 loci showed evidence of null alleles. No significant linkage disequilibrium was detected in the pairwise comparisons among the 22 loci. These markers are expected to be useful for the population genetic analysis of N. bathybius.

Recovering Ga(III) from coordination complexes using pyridine 2,6-dicarboxylic acid chelation ion chromatography

Ion exchange chelation chromatography is an effective means to extract metals from coordination complexes and biological samples; however there is a lack of data to verify the nature of metal complexes that can be successfully analysed using such a procedure. The aim of this study was to assess the capability of pyridine 2,6-dicarboxylic acid (PDCA) to extract and quantify Ga(III) from a range of environments using standard liquid chromatography apparatus. The PDCA chelation method generated a single Ga(III) peak with a retention time of 2.55 +/- 0.02 min, a precision of <2% and a limit of detection of 110 microM. Ga(III) hydroxide complexes (highest stability constant 15.66) were used to successfully cross-validate the chelation method with inductively coupled plasma mass spectrometry. The PDCA assay extracted 96.9 +/- 1.2% of the spiked Ga(III) from porcine mucus and 100.7 +/- 2.7% from a citrate complex (stability constant 10.02), but only ca 50% from an EDTA complex (stability constant 22.01). These data suggest that PDCA chelation can be considered a suitable alternative to inductively coupled plasma mass spectrometry for Ga(III) quantification from all but the most strongly bound coordinated complexes i.e. a stability constant of <15.

High-Affinity Capture of Proteins by Diamond Nanoparticles for Mass Spectrometric Analysis

Carboxylated/oxidized diamond nanoparticles (nominal size 100 nm) exhibit exceptionally high affinity for proteins through both hydrophilic and hydrophobic forces. The affinity is so high that proteins in dilute solution can be easily captured by diamonds, simply separated by centrifugation, and directly analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). No preseparation of the adsorbed molecules from diamonds is required for the mass spectrometric analysis. Compared to conventional MALDI-TOF-MS, an enhancement in detection sensitivity by more than 2 orders of magnitude is achieved for dilute solution containing cytochrome c, myoglobin, and albumin because of preconcentration of the probed molecules. The lowest concentration detectable is 100 pM for a 1-mL solution. Aside from the enhanced sensitivity, the overall performance of this technique does not show any sign of deterioration for highly contaminated protein solutions, and furthermore, no significant peak broadening and band shift were observed in the mass spectra. The promise of this new method for clinical proteomics research is demonstrated with an application to human blood serum.