Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Insecticide resistance of Anopheles sinensis after elimination of malaria in Henan Province, China

BACKGROUND

Historically, malaria due to Plasmodium vivax has been epidemic in Henan Province, China, with Anopheles sinensis as the main vector. The most effective measures to prevent malaria transmission are based on vector control through the use of insecticides. However, insecticides exert a strong selective pressure on mosquito populations for insecticide resistance. The aim of this study was to investigate the susceptibility profile and population genetic characteristics of An. sinensis to provide basic data and scientific guidance for the study of resistance mechanisms and the control of An. sinensis in Henan Province.

METHODS

Adult Anopheles mosquitoes were collected at sites near local farmers' sheepfolds, pigsties and/or cowsheds located in Pingqiao, Xiangfu, Xiangcheng and Tanghe counties/districts of Henan Province during July-September 2021 for insecticide susceptibility testing. Molecular identification of collected mosquitoes as belonging to genus Anopheles was by PCR, and the frequencies of mutations in the knockdown resistance gene (kdr) and acetylcholinesterase-1 gene (ace-1) were detected using gene amplification. The mitochondrial DNA cytochrome oxidase subunit I (COI) gene was amplified in deltamethrin-resistant and deltamethrin-sensitive mosquitoes to analyze the genetic evolutionary relationship.

RESULTS

A total of 1409 Anopheles mosquitoes were identified by molecular identification, of which 1334 (94.68%) were An. sinensis, 28 (1.99%) were An. yatsushiroensis, 43 (3.05%) were An. anthropophagus and four (0.28%) were An. belenrae. The 24-h mortality rates of An. sinensis in Pingqiao, Tanghe, Xiangcheng and Xiangfu counties/districts exposed to deltamethrin were 85.85%, 25.38%, 29.73% and 7.66%, respectively; to beta-cyfluthrin, 36.24%, 70.91%, 34.33% and 3.28%, respectively; to propoxur, 68.39%, 80.60%, 37.62% and 9.29%, respectively; and to malathion, 97.43%, 97.67%, 99.21% and 64.23%, respectively. One mutation, G119S, was detected in the ace-1 gene. The frequencies of the main genotypes were 84.21% of specimens collected in Xiangfu (G/S), 90.63% of speciments collected in Xiangcheng (G/G) and 2.44% of speciments collected in Tanghe (S/S). Significantly higher G119S allele frequencies were observed in both propoxur- and malathion-resistant mosquitoes than in their sensitive counterparts in the Tanghe population (P < 0.05). Three mutations, L1014F (41.38%), L1014C (9.15%) and L1014W (0.12%), were detected in the kdr gene. The genotypes with the highest frequency in the populations of An. sinensis in Xiangfu and Tanghe were the mutant TTT (F/F) and wild-type TTG (L/L), at 67.86% (57/84) and 74.29% (52/70), respectively. In Pingqiao and Xiangfu, higher frequencies of the L1014F allele and lower frequencies of the L1014C allele were observed in mosquitoes resistant for beta-cyfluthrin than in those which were sensitive for this insecticide (P < 0.05). The results of Tajima's D and of Fu and Li's D and F were not significantly negative (P > 0.10), and each haplotype was interlaced and did not form two distinct branches.

CONCLUSIONS

High resistance to pyrethroids and propoxur was observed at four sites, but the resistance to malathion varied according to the location. Anopheles belenrae and the L1014W (TGG) mutation in An. sinensis were first discovered in Henan Province. The deltamethrin-resistant and deltamethrin-sensitive mosquito populations showed no genetic differentiation. The generation of resistance might be the result of the combination of multiple factors.

Genetic polymorphism of circumsporozoite protein of Plasmodium falciparum among Chinese migrant workers returning from Africa to Henan Province

BACKGROUND

Plasmodium falciparum malaria is recognized as a major global public health problem. The malaria vaccine was important because the case fatality rate of falciparum malaria was high. Plasmodium falciparum circumsporozoite protein (PfCSP) is one of the potential vaccine candidates, but the genetic polymorphism of PfCSP raises concerns regarding the efficacy of the vaccine. This study aimed to investigate the genetic polymorphism of PfCSP and provide data for the improvement of PfCSP-based vaccine (RTS,S malaria vaccine).

METHODS

Blood samples were collected from 287 Chinese migrant workers who were infected with P. falciparum and returning from Africa to Henan Province during 2016-2018. The Pfcsp genes were analysed to estimate the genetic diversity of this parasite.

RESULTS

The results showed that there were two mutations at the N-terminus of imported Pfcsp in Henan Province, including insertion amino acids (58.71%, 118/201) and A → G (38.81%, 78/201). The number of repeats of tetrapeptide motifs (NANP/NVDP/NPNP/NVDA) in the central repeat region ranged mainly from 39 to 42 (97.51%, 196/201). A total of 14 nonsynonymous amino acid changes were found at the C-terminus. The average nucleotide difference (K) of imported Pfcsp in Henan Province was 5.719, and the haplotype diversity (Hd) was 0.964 ± 0.004. The estimated value of dN-dS was 0.047, indicating that the region may be affected by positive natural selection. The minimum number of recombination events (Rm) of imported Pfcsp in Henan Province was close to that in Africa. The analysis of genetic differentiation showed that there may be moderate differentiation between East Africa and North Africa (Fst = 0.06484), and the levels of differentiation in the other regions were very small (Fst < 0.05).

CONCLUSIONS

The N-terminus of Pfcsp was relatively conserved, and the central repeat region and the Th2R and Th3R regions of the C-terminus were highly polymorphic. The gene polymorphism pattern among Chinese migrant workers returning from Africa to Henan Province was consistent with that in Africa. The geographical pattern of population differentiation and the evidence of natural selection and gene recombination suggested that the effect of polymorphism on the efficacy of PfCSP-based vaccines should be considered.

[Epidemiological investigation on a visceral leishmaniasis case in Zhengzhou City of Henan Province]

OBJECTIVE

To perform an epidemiological investigation on a case with visceral leishmaniasis in Zhengzhou City, Henan Province, and to identify the source of infection, so as to illustrate the transmission chain and assess the risk of local leishmaniasis transmission.

METHODS

The medical data were collected from a case with visceral leishmaniasis in Zhengzhou City, and the patient's bone marrow smears were detected by microscopy. Serum anti-Leishmania antibody test and PCR assay were performed among high-risk residents and all dogs in the village where the patient lived. Sandflies were captured using light traps and artificial traps, and the captured female Phlebotomus chinensis was subjected to PCR assay. The internal transcribed spacer 1 (ITS1) gene was amplified with a nested PCR assay using the genomic DNA extracted from visceral leishmaniasis patients, positive dogs and sandflies, and the sequences were aligned with those download from NCBI. In addition, a phylogenetic tree was created based on the ITS1 gene.

RESULTS

The visceral leishmaniasis patient had recurrent irregular fever, reduced complete blood counts, low hemoglobin, and a large number of Leishmania amastigotes in bone marrow smears, and was therefore diagnosed as visceral leishmaniasis. Both rk39 rapid diagnostic test and PCR assay tested negative among 324 residents living neighboring the patient's residence, while 21.39% (43/201) dogs were positive for rk39 rapid diagnostic test and 13.93% (28/201) positive for PCR assay. There were 17 female Ph. chinensis tested positive for Leishmania (0.82%) by PCR assay, and the ITS gene sequences from visceral leishmaniasis patients, positive dogs and sandflies shared a 100% homology with L. infantum. The Leishmania species was therefore characterized as L. infantum.

CONCLUSIONS

L. infantum infection occurs in visceral leishmaniasis patients, dogs and sandflies in Zhengzhou City, indicating a complete transmission chain and a high transmission risk of visceral leishmaniasis by L. infantum. Intensified control measures are required to prevent local transmission of leishmaniasis in Zhengzhou City.

One Health approach to improve the malaria elimination programme in Henan Province

One Health is a collaborative, multi-sectoral, trans-disciplinary approach with the goal of achieving optimal health outcomes by recognizing the interconnection between people, animals, plants, and the environment and determining how this relates to the control of infectious diseases such as malaria, schistosomiasis and so on. Malarias caused by Plasmodium that commonly infects female Anopheles mosquitoes, which feed on human blood and act as a disease vector. It has been a worldwide important public health problem from ancient times. Also, malaria is one of the infectious diseases with the longest epidemic time and the most serious harm in the history of Henan Province, China. During the past decades, the multi-sectoral, cross-regional, and multi-disciplinary One Health approach contributed to a significant reduction in malaria incidence, resulting in initiation of the Henan Malaria Elimination Action Plan. Herein, we reviewed the history of the fight against malaria in Henan Province. A full picture of malaria epidemics, prevention, and control strategies were showed, with the objective that it will help stakeholders, and policy-makers to take informed decisions on public health issues and intervention designs on malaria control towards elimination in the similar areas.

[The application value of plasma heterogeneous nuclear ribonucleoprotein A2/B1, Aβ42 and P-tau in the preoperative diagnosis of mild cognitive dysfunction]

Objective: To explore the application value of plasma heterogeneous nuclear ribonucleoprotein A2/B1(hnRNP A2B1), β-amyloid 42(Aβ₄₂) and phosphorylated tau protein(P-tau) levels in elderly patients in the preoperative diagnosis of mild cognitive impairment(MCI). Methods: A total of 200 patients who underwent elective surgery at Tianjin Third Central Hospital from June 2020 to March 2021were Enrolled, regardless of gender, age 65-80 years old. According to the international MCI working group standards and the European Alzheimer's Disease Federation working group standards, patients were divided into MCI group and control group. There were 58 males and 42 females in each group. The patient's plasma hnRNP A2/B1, Aβ₄₂ and P-tau levels were detected before operation. The sensitivity, specificity and accuracy of the diagnosis of MCI were calculated. The receiver operating characteristic curve were drew to evaluate the diagnostic value of each index. Results: The plasma levels of hnRNP A2/B1, Aβ₄₂ and P-tau in the MCI group were 310.0 (275.1, 344.2), 34.5 (24.9, 42.5), 190.4 (150.4, 301.7) ng/L, respectively, which were significantly higher than those of the control group [272.7 (239.6, 291.5), 18.7 (14.7, 26.6), 140.0 (101.8, 217.5) ng/L]. The differences were statistically significant (all P<0.05). Taking the international MCI working group standard as the gold standard, the sensitivity, specificity and area under the ROC curve (AUC) of plasma hnRNP A2/B1 for predicting MCI were 80%, 61%, and 0.781, respectively. The sensitivity, specificity and AUC of plasma Aβ₄₂ for predicting MCI were 78%, 73%, and 0.744. The sensitivity, specificity, and AUC of P-tau for predicting MCI were 51%, 79%, and 0.675, respectively. The sensitivity, specificity and AUC of hnRNP A2/B1 and Aβ₄₂ in predicting MCI were not statistically significant (all P>0.05), but the sensitivity of both were higher than P-tau (all P<0.001). Compared with P-tau, the AUC of plasma hnRNP A2/B1 was higher when predicting MCI (P<0.05). When the three indicators were combined, the sensitivity was 82%, and the AUC was 0.842, both of which were the highest, but the specificity reduced (71%) (all P<0.05). Conclusions: Plasma hnRNP A2/B1 combined with Aβ₄₂ and P-tau levels can improve the sensitivity and accuracy of MCI diagnosis in elderly MCI patients before surgery, and have the greatest diagnostic efficiency. It has certain application value.

[Clinical characteristics of human adenovirus infection in hospitalized children with acute respiratory infection in Beijing]

Objective: To compare the clinical characteristics of different types of human adenovirus (HAdV) infection in hospitalized children with acute respiratory infection in Beijing, and to clarify the clinical necessity of adenovirus typing. Methods: In a cross-sectional study, 9 022 respiratory tract specimens collected from hospitalized children with acute respiratory infection from November 2017 to October 2019 in Affiliated Children's Hospital, Capital Institute of Pediatrics were screened for HAdV by direct immunofluorescence (DFA) and (or) nucleic acid detection. Then the Penton base, Hexon and Fiber gene of HAdV were amplified from HAdV positive specimens to confirm their HAdV types by phylogenetic tree construction. Clinical data such as laboratory results and imaging data were analyzed for children with predominate type HAdV infection using t, U, or χ² test. Results: There were 392 cases (4.34%) positive for HAdV among 9 022 specimens from hospitalized children with acute respiratory infection. Among those 205 cases who were successfully typed, 131 were male and 74 were female, age of 22.6 (6.7, 52.5) months,102 cases (49.76%) were positive for HAdV-3 and 86 cases (41.95%), HAdV-7, respectively, while 17 cases were confirmed as HAdV-1, 2, 4, 6, 14 or 21. In comparison of clinical characteristics between the predominate HAdV type 7 and 3 infection, significant differences were shown in proportions of children with wheezing (10 cases (11.63%) vs. 25 cases (24.51%)), white blood cell count >15 ×10⁹/L (4 cases (4.65%) vs.14 cases (13.73%)), white blood cell count <5×10⁹/L (26 cases (30.23%) vs.11 cases (10.78%)), procalcitonin level>0.5 mg/L (43 cases (50.00%) vs. 29 cases (28.43%)), multilobar infiltration (45 cases (52.33%) vs.38 cases (37.25%)), pleural effusion (23 cases (26.74%) vs. 10 cases (9.80%)), and severe adenovirus pneumonia (7 cases (8.14%) vs. 2 cases (1.96%)) with χ²=5.11, 4.44, 11.16, 9.19, 4.30, 9.25, 3.91 and P=0.024, 0.035, 0.001, 0.002, 0.038, 0.002, 0.048, respectively, and also in length of hospital stay (11 (8, 15) vs. 7 (5, 13) d, Z=3.73, P<0.001). Conclusions: HAdV-3 and 7 were the predominate types of HAdV infection in hospitalized children with acute respiratory tract infection in Beijing. Compared with HAdV-3 infection, HAdV-7 infection caused more obvious inflammatory reaction, more severe pulmonary symptoms, longer length of hospital stay, suggesting the clinical necessity of further typing of HAdVs.

[Effectiveness of health education interventions targeting taeniasis and cysticercosis among primary school students in disease-elimination pilot areas of Henan Province]

OBJECTIVE

To compare the changes of knowledge, attitude and practice (KAP) related to taeniasis and cysticercosis among primary school students before and after health education interventions in disease-elimination pilot areas of Henan Province, so as to evaluate the effectiveness of health education interventions.

METHODS

A primary school was selected from each of Dushu, Bowang and Yangji townships, Fangcheng County, Henan Province from 2017 to 2019; then, 2 to 3 classes were randomly selected from grade 4 to 6 in each primary school, and finally, all students in these classes were enrolled as study subjects. A thematic health education lecture pertaining to taeniasis and cysticercosis was given once each year by means of "health education in class". The KAP towards taeniasis and cysticercosis was investigated among primary school students using selffilled structured questionnaires, and the changes of awareness of taeniasis and cysticercosis control knowledge and percentage of healthy behaviors formation were compared in primary school students among years and following various frequencies of health education interventions.

RESULTS

More than 10 thousand person-time primary school students received health education interventions during the period from 2017 to 2019, and a total of 1 223 person-time primary school students were investigated during the 3-year study period, including 633 person-time men and 590 person-time women and 88.55% of primary school students at ages of 10 to 12 years. The proportion of households raising pigs and using dry toiliets decreased from 5.30% (24/453) and 18.10% (82/453) in 2017 to 3.60% (13/361) and 11.08% (40/361) in 2019, respectively. The awareness rate of taeniasis and cysticercosis control knowledge increased significantly from 0.22% (1/453) in 2017 to 62.59% (256/409) in 2018 and 76.73% (277/361) in 2019 (χ² = 567.60, P < 0.001), and the awareness rate was 85.25% (104/122) among primary school students attending the thematic special health education courses for successive three times. The awareness rates of taeniasis and cysticercosis control knowledge were 0.44% (1/225), 58.00% (116/200) and 71.63% (149/208) among male students and 0 (0/338), 66.99% (140/209) and 83.66% (128/153) among female students from 2017 to 2019, and there was a significant difference in the awareness of taeniasis and cysticercosis control knowledge between male and female students in 2019 (χ² = 7.14, P = 0.01). On-site teaching by doctors was the students' favorite way to receive health education interventions (70.07%, 857/1 223), followed by watching health education videos (58.63%, 717/1 223) and seeing parasite specimens (48.9%, 598/1 223). The proportion of students' families who used cutting boards for raw and cooked food separately increased from 7.28% (33/453) in 2017 to 47.37% (171/361) in 2019, was 67.21% (82/122) among students attending the health education courses for successive three times. The proportion of students who frequently washed their hands before meals and after using toilet increased from 71.96% (324/453) in 2017 to 89.47% (319/361) in 2019 and was 95.90% (117/122) among students attending the health education courses for successive three times. In addition, the percentage of students washing hands frequently in families using dry toilets was significantly lower in those who did not use dry toilets (χ² = 9.21, P = 0.002), and the proportion of students with a habit of eating raw or undercooked meat decreased significantly from 35.76% (162/453) in 2017 to 6.65% (24/361) in 2019 (χ² = 69.11, P < 0.01).

CONCLUSIONS

The thematic health education activity of "health education in class" contributes greatly to the increase in the awareness of taeniasis and cysticercosis control knowledge and the rate of healthy behaviors formation among primary school students in diseaseelimination pilot areas of Henan Province.

[Clinical characteristics of children infected with different subtypes/genotypes of human respiratory syncytial virus in Beijing from 2009 to 2017]

Objective: To explore the different clinical characteristics of children infected with different subtype/genotype of human respiratory syncytial virus (HRSV) in Beijing. Methods: Respiratory specimens for positive HRSV were randomly collected from children with acute respiratory tract infection (ARTI) in the epidemic season of HRSV from November of each year to January of the next year during 2009 and 2017. G genes of HRSV were amplified and sequenced for subtyping and genotyping by bioinformatics analysis. Clinical data were collected and analyzed. Results: Out of 590 children, 376 (63.7%) with subtype A, and 214 (36.3) with subtype B. The annual dominant subtypes of HRSV from 2009 to 2017 were B-A-A-B-AB-A-A-B-A, respectively, whilst a total of 10 genotypes were detected with 95.8% assigned to genotype ON1 and NA1 of subtype A, and genotype BA9 of subtype B. Children infected with subtype B (96 cases, 44.9%) were more likely aged 0-3 month old than those with subtype A (118 cases, 31.4%) (P=0.001), and more likely to be admitted to Intensive Care Unit(ICU) ((124 cases, 57.9%) than those with subtype A (172 cases, 45.7%)) (P=0.005). Statistical significance were shown among children infected with genotype ON1, NA1 or BA9, in the possibility of infection in children aged 0-3 month (P=0.003), proportion of admission into ICU (P=0.007), length of stay in hospital (P=0.001), and clinical outcome (P=0.001), respectively. Conclusion: Children infected with different subtype or genotype of HRSV have different clinical characteristics, which stresses the important role of the monitoring HRSV subtypes and genotypes among children.

Relationship Between the Serotypes and Hemagglutinin Gene Sequences of Avibacterium paragallinarum

Avibacterium paragallinarum has been subtyped into three serogroups (A, B, and C) and nine serovars (A-1, A-2, A-3, A-4, B-1, C-1, C-2, C-3, and C-4) according to the Page and Kume schemes. Both schemes use the hemagglutination inhibition test for serotyping. However, the relationship between the hemagglutinin gene (HMTp210) sequences and serotypes of A. paragallinarum is still unclear. This problem is partly due to the lack of information on the complete HMTp210 sequence from the formal reference strain of Page serogroup B (strain 0222 or Spross). In this study, we determined the complete HMTp210 sequence of strain Spross. The sequence of Spross and those of other HMTp210 sequences retrieved from GenBank were used to conduct phylogenetic analyses to investigate the relationship between the serotypes and HMTp210 sequences of A. paragallinarum. Four phylogenetic clusters, designated clusters A-1, A-2, B, and C, were identified. Clustering based on complete HMTp210 sequences correlates with serotyping based on hemagglutination inhibition tests. Serovar A-2 was found to contain a chimeric HMTp210 gene that might have resulted from recombination between serovar A-1 and serovar C-1. In addition, phylogenetic analysis based on partial sequences (approximately nucleotides 1-1200) of HMTp210 was sufficient to discriminate between serogroups A, B, and C. These findings could be valuable for developing a molecular method for serotyping of A. paragallinarum.

[Susceptibility of Anopheles sinensis to insecticides in Puyang City, Henan Province]

OBJECTIVE

To investigate the susceptibility of Anopheles sinensis to malathion, deltamethrin and lambda-cyhalothrin in Puyang City, Henan Province, so as to provide the scientific basis for local malaria vector control.

METHODS

An. sinensis was captured from Puyang County, Puyang City of Henan Province in September 2018 and July 2020, and the susceptibility of field captured An. sinensis to malathion, deltamethrin and lambda-cyhalothrin was tested using the filter-paper bioassay recommended by WHO. The insecticide resistance level was assessed based on the WHO criteria.

RESULTS

In 2018 and 2010, the half knock-down times (KT₅₀) of malathion were 91.08 min and 40.95 min for An. sinensis, with knock-down rates of 37.50% and 60.87% 60 min post-exposure to malathion and 24-hour mortality rates of 90.91% and 100%, respectively, and the insecticide resistance levels were moderately resistant (M) and susceptible (S). The KT₅₀ of deltamethrin were 415.56 min and 341.19 min for An. sinensis in 2018 and 2020, with knock-down rates of 22.92% and 16.98% 60 min post-exposure to malathion and 24-hour mortality rates of 22.92% and 16.98%, and the insecticide resistance levels were all resistant (R). The KT₅₀ of lambda-cyhalothrin were 164.22 min and 236.22 min for An. sinensis in 2018 and 2020, with knock-down rates of 30.39% and 38.30% 60 min postexposure to malathion and 24 h mortality rates of 19.60% and 21.28%, respectively, and the insecticide resistance levels were all R.

CONCLUSIONS

An. sinensis is relatively susceptible to malathion but has developed high-level resistance to deltamethrin and lambda-cyhalothrin in Puyang City, Henan Province..

[Prevalence of intestinal protozoan infections among rural children in Henan Province from 2014 to 2015]

OBJECTIVE

To investigate the prevalence and influencing factors of intestinal protozoan infections among rural children in Henan Province.

METHODS

A total of 104 survey sites were sampled from 35 counties (cities) in Henan Province using the stratified cluster sampling method to investigate the prevalence of intestinal protozoan infections among rural children from 2014 to 2015. The trophozoites and cysts of intestinal protozoa were identified using the iodine staining method and the physiological saline direct smear method (one detection for one stool sample). The prevalence of intestinal protozoan infections was compared among rural children with different characteristics, and the factors affecting intestinal protozoan infections among rural children were identified.

RESULTS

The overall prevalence of intestinal protozoan infections was 0.60% (40/6 771) among rural children in Henan Province from 2014 to 2015. There were 7 species of intestinal protozoa identified, and there was no species-specific prevalence (χ² = 37.732, P = 0.000). No significant differences were found in prevalence of intestinal protozoan infections among rural children in terms of gender (χ² = 1.793, P = 0.181), age (χ² = 1.443, P = 0.486), occupation (χ² = 0.219, P = 0.896) or ecological region (χ² = 1.700, P = 0.637). In addition, terrain (χ² = 2.311, P = 0.510), economic level (χ² = 4.322, P = 0.229), source of drinking water (χ² = 0.731, P = 0.393), eating raw vegetables (χ² = 1.134, P = 0.287) and deworming (χ² = 1.089, P = 0.297) had no remarkable effects on the prevalence of intestinal protozoan infections among rural children in Henan Province; however, the prevalence of intestinal protozoan infections varied significantly among rural children living in regions with different coverage of non-harmless toilets (χ² = 10.050, P = 0.018).

CONCLUSIONS

The prevalence of intestinal protozoan infections is low among rural children in Henan Province.

Efficient Face Detection in the Fisheye Image Domain

Significant progress has been made for face detection from normal images in recent years; however, accurate and fast face detection from fisheye images remains a challenging issue because of serious fisheye distortion in the peripheral region of the image. To improve face detection accuracy, we propose a light-weight location-aware network to distinguish the peripheral region from the central region in the feature learning stage. To match the face detector, the shape and scale of the anchor (bounding box) is made location dependent. The overall face detection system performs directly in the fisheye image domain without rectification and calibration and hence is agnostic of the fisheye projection parameters. Experiments on Wider-360 and real-world fisheye images using a single CPU core indeed show that our method is superior to the state-of-the-art real-time face detector RFB Net.

Interleukin 13 (IL-13)-regulated expression of the chondroprotective metalloproteinase ADAM15 is reduced in aging cartilage

Objective

The adamalysin metalloproteinase 15 (ADAM15) has been shown to protect against development of osteoarthritis in mice. Here, we have investigated factors that control ADAM15 levels in cartilage.

Design

Secretomes from wild-type and Adam15^−/− chondrocytes were compared by label-free quantitative mass spectrometry. mRNA was isolated from murine knee joints, either with or without surgical induction of osteoarthritis on male C57BL/6 mice, and the expression of Adam15 and other related genes quantified by RT-qPCR. ADAM15 in human normal and osteoarthritic cartilage was investigated similarly and by fluorescent immunohistochemistry. Cultured HTB94 chondrosarcoma cells were treated with various anabolic and catabolic stimuli, and ADAM15 mRNA and protein levels evaluated.

Results

There were no significant differences in the secretomes of chondrocytes from WT and Adam15^−/− cartilage. Expression of ADAM15 was not altered in either human or murine osteoarthritic cartilage relative to disease-free controls. However, expression of ADAM15 was markedly reduced upon aging in both species, to the extent that expression in joints of 18-month-old mice was 45-fold lower than in that 4.5-month-old animals. IL-13 increased expression of ADAM15 in HTB94 ​cells by 2.5-fold, while modulators of senescence and autophagy pathways had no effect. Expression of Il13 in the joint was reduced with aging, suggesting this cytokine may control ADAM15 levels in the joint.

Conclusion

Expression of the chondroprotective metalloproteinase ADAM15 is reduced in aging human and murine joints, possibly due to a concomitant reduction in IL-13 expression. We thus propose IL-13 as a novel factor contributing to increased osteoarthritis risk upon aging.

[Epidemiological characteristics of malaria in Henan Province from 1950 to 2019]

OBJECTIVE

To analyze the epidemiological characteristics of malaria in Henan Province from 1950 to 2019, so as to provide the scientific evidence for consolidating malaria elimination achievements in the province.

METHODS

The epidemiological situation of malaria and demographic data in Henan Province from 1950 to 2019 were collected, and the statistical analyses were performed using a descriptive epidemiological method. The spatial temporal distribution of malaria cases was identified using the software ArcGIS version 10.3.

RESULTS

During the period from 1950 through 2019, the progress of malaria elimination was divided into 4 stages in Henan Province, including the baseline-survey and key-control stage, morbidity-control and incidence-reduction stage, basic-eradication and achievement-consolidation stage and elimination stage. The spatial distribution of malaria cases shifted from south of the Huai River and the plain regions between the Yellow River and Taihang Mountain to the Huang-Huai-Hai Plain and Nanyang Basin, then was concentrated in eastern part of southern Huai River where Anopheles anthropophagus was distributed, and finally was gradually under control following malaria outbreak in Eastern Henan Plain. In addition, the species of Plasmodium changed from P. vivax, P. falciparum and P. malariae co-endemics to a single P. vivax infection, and the current co-endemics of 5 invasive malaria parasites, and the malaria vectors shifted from co-existence of Anopheles sinensis and An. anthropophagus to An. sinensis alone.

CONCLUSIONS

There has been a large change in the epidemiological characteristics of malaria in Henan Province from 1950 to 2019. Although malaria has been eliminated in Henan Province, the consolidation of the malaria elimination achievements remain a great challenge due to overseas imported malaria.

[Diagnosis of imported malaria cases in Henan Province from 2015 to 2019]

OBJECTIVE

To analyze the diagnosis of imported malaria cases in Henan Province from 2015 to 2019, so as to provide the evidence for malaria surveillance during the post-elimination stage.

METHODS

The data pertaining to malaria cases in Henan Province from 2015 to 2019 were extracted via the web-based Chinese Information System for Infectious Diseases Control and Prevention and the Parasitic Diseases Information Reporting Management System (PDIRMS) of Chinese Center for Disease Control and Prevention, and the diagnostic methods, diagnostic institutions and diagnostic time of imported malaria cases were analyzed.

RESULTS

A total of 952 imported malaria cases were reported in Henan Province during the period from 2015 through 2019, and all cases were laboratory-confirmed. The positive rate of malaria rapid diagnostic tests (RDTs) was 98.61% (779/790), which was significantly greater than that (94.22%, 897/952) of microscopic examinations (χ² = 22.773, P < 0.05). The proportion of imported malaria cases diagnosed in medical institutions increased from 65.22% (120/184) in 2015 to 81.50% (185/227) in 2019. Among the 238 imported malaria cases diagnosed in centers for disease control and prevention (CDC), 71.01% (169/238) were diagnosed in county-level CDC, and among the 704 cases diagnosed in medical institutions, only 8.38% (59/704) were diagnosed at county-level medical institutions. The median time from onset to definitive diagnosis of malaria was 3 days, and the median duration between onset and initial diagnosis of malaria was 1 day. The duration between initial diagnosis and definitive diagnosis of malaria varied significantly among years (χ² = 24.956, P < 0.05), and the interquartile range from initial diagnosis to definitive diagnosis reduced from 4 days in 2016 to 2 days in 2019. In addition, the median time from initial diagnosis to definitive diagnosis was significantly longer in severe falciparum malaria cases than in non-severe falciparum malaria cases (2 days vs. 1 day; Z = 7.557, P < 0.05).

CONCLUSIONS

Medical institutions play a more and more important role in the identification and surveillance of malaria cases; however, the diagnostic capability of malaria remains low in county-level medical institutions. The diagnostic awareness and capability of county-level medical institutions requires to be improved, in order to play their roles as sentinel hospitals in the malaria surveillance during the post-elimination stage.

[Epidemic status of malaria and progress of malaria elimination in Henan Province, 2018]

OBJECTIVE

To understand the epidemic status of malaria and progress of malaria elimination in Henan Province in 2018, so as to provide the scientific evidence for formulating the control strategy of malaria.

METHODS

All data pertaining to the epidemic status of malaria and malaria case were captured from Henan Province in 2018, and the epidemic status of malaria and the diagnosis and treatment of malaria cases were analyzed using a descriptive epidemiological method.

RESULTS

A total of 174 malaria cases were reported in Henan Province in 2018, with a male-to-female ratio of 33.8∶1. The cases were predominantly found at 30- and 40- years, and farmer was the highest-risk population. All cases were imported for overseas countries and 96.55% (168/174) were from Africa. The cases were reported across 17 cities of the province, and 63.22% (110 cases) were detected in 4 cities of Zhengzhou, Luoyang, Xuchang and Puyang. Both the median duration from onset to initial admission and the median time from the initial admission to definitive diagnosis were 1 d. There were 6 cases (3.45%) with more than 7 days to visit a doctor, and there were 13 cases (7.47%) with definitive diagnosis of over 7 days (delay in definitive diagnosis). All malaria cases were reported within 24 h, and 98.28% (171/174) completed case investigations within 3 d. All 18 cities had achieved malaria elimination by December 2018.

CONCLUSIONS

All malaria cases reported in Henan Province in 2018 are imported from overseas countries. Intensifying malaria surveillance among returnees from Africa and Southeast Asia and timely identification and treatment of imported malaria cases are required to prevent the development of secondary malaria cases, so as to ensure the achievement of malaria elimination in Henan Province on schedule.

[Prevalence and influencing factors of intestinal parasitic diseases among rural children in Henan Province]

OBJECTIVE

To understand the epidemic status and influencing factors of intestinal parasitic diseases among rural children in Henan Province.

METHODS

According to the Scheme for The National Survey on Current Status of Major Human Parasitic Diseases in China, the survey counties were selected based on the ecological zones and economic levels in Henan Province between 2014 and 2015. Then, the included counties were stratified according to the topography and economic levels. A township was randomly sampled from each stratum, and a village was randomly sampled from each township as the study site. Finally, a total of 104 study sites from 35 counties were enrolled for the survey of intestinal parasitic diseases in children. At least 250 fresh stool samples were collected from each study site for detection of intestinal helminth eggs with the Kato-Katz technique, for the identification of Necator americanus and Ancylostoma duodenale with the fecal culture method, and for the detection of intestinal protozoa trophozoite and cyst with the physiological saline smear and iodine staining techniques. In addition, the Enterobius vermicularis and tapeworm eggs were detected in children aged 3 to 6 years using the adhesive cellophane-tape perianal swab method.

RESULTS

The overall prevalence of intestinal parasitic infections was 3.21% (214/6 671) among rural children in Henan Province, and the prevalence of intestinal helminthes (2.62%, 175/6 671) was higher than that of intestinal protozoa (0.60%, 40/6 671). A total of 12 species of intestinal parasites were found, including 4 nematodes species, one trematode species, and 7 protozoa species, and the highest infection was seen in E. vermicularis (2.47%, 161/6 671). Among the four ecological zones in Henan Province, the greatest prevalence of intestinal parasitic infections was detected among children in the Qinba Mountain Ecological Zone (5.85%, 90/1 538). There was no gender-specific difference in the prevalence of intestinal parasitic infections in children (P > 0.05); however, there were age- (χ² = 32.762, P < 0.05) and education level-specific differences in the prevalence of intestinal parasitic infections in children (χ² = 67.507, P < 0.05), with the greatest prevalence of E. vermicularis infection seen in all species of intestinal parasites in children at all age groups. Multivariate non-conditional logistic regression analysis showed that high education level, high coverage of harmless toilets, drinking tap water and deworming were protective factors for intestinal parasitic infections in children in Henan Province. The overall prevalence of intestinal parasitic infections appeared a tendency towards a gradual decline among children in Henan Province as compared to the previous two surveys.

CONCLUSIONS

The overall prevalence of intestinal parasitic infections shows a tendency towards a remarkable decline among children in Henan Province. E. vermicularis infection should be given a priority for future parasitic disease control activities among rural children in Henan Province.

[Clinical analysis of seven cases of rare hemolytic disease of the newborn]

Objective: To summarize the clinical features of 7 rare cases of hemolytic disease of newborn (HDN), and to improve the understanding of rare HDN. Methods: Data of clinical information, laboratory findings, treatments and outcomes were collected and analyzed for four cases with HDN due to anti-M, two cases due to anti-Kidd, and one case due to anti-Duffy. All of them were admitted to the Department of Neonatology, Beijing Children's Hospital Affiliated to Capital Medial University from July 2007 to June 2017. Results: Among the four MN hemolytic babies, two were males and two were females. Jaundice was found in three cases. Two cases had hyperbilirubinemia, one of them had severe hyperbilirubinemia. All the four cases developed anemia, including severe anemia in three cases. Two cases of Kidd hemolytic disease and 1 case of Duffy hemolytic disease had jaundice and anemia, but did not reach the level of severe hyperbilirubinemia and severe anemia. MN hemolytic disease babies got negative results in direct antiglobulin test, whereas the Kidd and Duffy hemolytic disease babies had positive findings in direct antiglobulin test. None of the babies had blood transfusion, and they were discharged from the hospital. Conclusions: Without maternal and fetal blood group incompatibility (ABO or Rh blood-group system), for early onset of jaundice, severe jaundice or anemia, antiglobulin test to mother and child earlier should be administered, and MN, Kidd, Duffy and other rare hemolytic disease of the newborn should be pay attention to.

Homogeneity of Different Functional mRNA Indicators for Wound Age Estimation

OBJECTIVES

To explore the homogeneity level of four different functional mRNA （PUM2, TAB2, Cx45 and CHRNA1） expressions in rats with skeletal muscle contusion.

METHODS

The relative expressions of PUM2, TAB2, Cx45 and CHRNA1 mRNAs were detected by quantitative real-time reverse transcription-polymerase chain reaction （RT-qPCR）. The coefficient of variation （CV） of the relative expressions for different individuals in each injury group was calculated. The extreme value of CV, cumulative variability, and CV_CV were compared.

RESULTS

A high CV of PUM2 and TAB2 mRNAs appeared on several different time points. However, the CV of Cx45 and CHRNA1 mRNAs was relatively low. The cumulative variability from high to low was PUM2, CHRNA1, TAB2 and Cx45 mRNAs. The relative expression of PUM2 mRNA was significantly higher than that of TAB2, Cx45 and CHRNA1 mRNAs （ P<0.05）. There was no statistical significance （P>0.05） in the CV_CV of the relative expression of TAB2, CHRNA1 and Cx45 mRNAs.

CONCLUSIONS

As the mRNAs involving in biological process regulation, PUM2 and CHRNA1 mRNAs show a lowest individual homogeneity of the relative expression followed by TAB2 mRNA. As the mRNAs participating in the composition of cellular structure, Cx45 and CHRNA1 mRNAs show a high individual homogeneity of the relative expressions. The functional classification should be considered for the screening of the mRNA indicators used for wound age estimation.

[Secretory carcinoma of the breast: clinical histopathologic and biological behaviors]

Objective: To investigate the clinicopathological and immunohistochemistrical features of secretory carcinoma of the breast (SCB), as well as its diagnosis and prognosis. Methods: Five cases of SCB were collected and specimens were fully drawn. Microscopic pathology examinations and immunohistochemistry(SP method)were performed. Results: Five cases were all female patients aged from 31 to 54 years old (with an average age of 38 years), and all patients initially presented with the painless breast lump, often near the areola. Macroscopically, all the tumors were relatively circumscribed, with a mean diameter of 2.1 cm(1.2-3.0 cm). Histologically, the tumors revealed different patterns (microcystic, solid, ductal, and so forth) and appeared large amounts of intracellular and extracellular eosinophilic PAS- and AB-PAS- positive secretory materials, as well as the granular eosinophilic cytoplasm. Immunohistochemistrically, the tumor cells were strongly positive for epithelial membrane antigen (EMA) and S-100. Three cases had negative expression for estrogen receptor (ER) and progesterone (PR), and two cases had weakly focal expression. Human epidermal growth factor receptor 2 (HER2) and P53 were negative, while only one case had weakly focal expression. The tumors were positive for CK7, CK5/6, CD10, but they were negative for CEA, smooth muscle actin (SMA) and P63 . The proliferation index of Ki-67 was 5%-8%. There was no patient with metastasis of the tumor in axillary lymph node. Except 1 case lost follow-up, and the rest had no recurrence or distant metastasis. Conclusions: SCB is very rare, with low malignancy, and has better prognosis, but it is usually classified as triple-negative breast cancer because of the immune phenotype. The correct diagnosis of this lesion depends on clinical characteristics, morphology and immunohistochemistry.

DS1/OsEMF1 interacts with OsARF11 to control rice architecture by regulation of brassinosteroid signaling

BACKGROUND

Plant height and leaf angle are important determinants of yield in rice (Oryza sativa L.). Genes involved in regulating plant height and leaf angle were identified in previous studies; however, there are many remaining unknown factors that affect rice architecture.

RESULTS

In this study, we characterized a dwarf mutant named ds1 with small grain size and decreased leaf angle,selected from an irradiated population of ssp. japonica variety Nanjing35. The ds1 mutant also showed abnormal floral organs. ds1 plants were insensitive to BL treatment and expression of genes related to BR signaling was changed. An F₂ population from a cross between ds1 and indica cultivar 93-11 was used to fine map DS1 and to map-based clone the DS1 allele, which encoded an EMF1-like protein that acted as a transcriptional regulator. DS1 was constitutively expressed in various tissues, and especially highly expressed in young leaves, panicles and seeds. We showed that the DS1 protein interacted with auxin response factor 11 (OsARF11), a major transcriptional regulator of plant height and leaf angle, to co-regulate D61/OsBRI1 expression. These findings provide novel insights into understanding the molecular mechanisms by which DS1 integrates auxin and brassinosteroid signaling in rice.

CONCLUSION

The DS1 gene encoded an EMF1-like protein in rice. The ds1 mutation altered the expression of genes related to BR signaling, and ds1 was insensitive to BL treatment. DS1 interacts with OsARF11 to co-regulate OsBRI1 expression.

Cultivation of auricular chondrocytes in poly(ethylene glycol)/poly(ε-caprolactone) hydrogel for tracheal cartilage tissue engineering in a rabbit model

Tissue engineering has the potential to overcome the limitations of tracheal reconstruction. To tissue-engineer a tracheal cartilage, auricular chondrocytes were encapsulated in a photocurable poly(ethylene glycol)/poly(ε-caprolactone) (PEG/PCL) hydrogel. Chondrogenic genes, including Sox9, Acan and Col2a1, were up-regulated in auricular chondrocytes after 2 weeks of in vitro cultivation in the PEG/PCL hydrogel. Co-cultivation of 70 % auricular chondrocytes and 30 % bone marrow mesenchymal stem cells (BMSCs) accelerated the chondrogenic genes' expression in the PEG/PCL hydrogel. Cartilaginous matrix markers, including proteoglycans and collagen type II, were detected in the chondrocytes-encapsulated PEG/PCL hydrogel after 4 weeks of in vitro cultivation. The higher expression level of cartilaginous matrix markers was observed in the PEG/PCL hydrogel with co-cultivation of 70 % chondrocytes and 30 % BMSCs. After 4 weeks of ectopic cultivation in rabbits, the cylindrical PEG/PCL structure was sustained with the use of a luminal silicon stent. However, without the stent, the construct collapsed under a compression force. No fibrosis or vessel ingrowth were found in the PEG/PCL hydrogel after 4 weeks of ectopic cultivation, whereas the auricular chondrocytes showed proteoglycans' accumulation and collagen type II production. Rabbit auricular chondrocytes could survive and retain chondrogenic ability in the PEG/PCL hydrogel under both in vitro and in vivo conditions. While the PEG/PCL hydrogel did not show sufficient mechanical properties for supporting the cylindrical shape of the construct, the high chondrogenesis level of chondrocytes in the PEG/PCL hydrogel displayed the potential of this material for tracheal tissue engineering.

Larval species composition and genetic structures of Carposina sasakii, Grapholita dimorpha, and Grapholita molesta from Korea

Rapid determination of the larval species composition and understanding of their genetic structure is important to establish the appropriate management system for multiple species infesting in fruits. We established accurate and rapid diagnostic methods based on multiplex polymerase chain reaction (PCR) diagnostic techniques to discriminate the three major lepidopteran species in orchard, Carposina sasakii, Grapholita dimorpha, and Grapholita molesta. Each species was identified by amplifying species-specific PCR products (375 bp for C. sasakii, 125 and 234 bp for G. dimorpha, and 125 bp for G. molesta). Based on species composition analysis from six types of infested fruits, G. dimorpha constituted the highest proportion (47.8%), followed by 35.2 and 13.5% for G. molesta and C. sasakii, respectively. Interestingly, high prevalence was found in G. dimorpha and G. molesta for plum and peach, respectively. Based on genetic diversity analysis, the three insect species exhibited moderate or high haplotype diversity and low nucleotide diversity, ranging from 0.319 to 0.699 and 0.0006 to 0.0045, respectively. Demographic expansion was not detected according to either a neutrality test or mismatch distribution analysis. Moreover, no significant genetic structure corresponding to province, host plant, fruit type, or collection period was observed. These results suggest that the population of each species would have high dispersal ability following fruit-generating periods via intrinsic host adaptation ability regardless of the spatial and temporal conditions. Determination of larval composition on fruit is valuable for establishing appropriate management systems that take the species into consideration; additionally, population genetic approaches can be utilized to understand the effects of environmental factors (province, host fruit, fruit type, etc.) on population structures.

[Stratified sampling survey of major human parasitic diseases in Henan province]

Objective: To understand the prevalence of major human parasitic diseases and related factors in Henan province. Methods: This stratified sampling survey was carried out according to the requirement of national survey protocol of major human parasitic diseases, 2014-2015. The prevalence of soil-transmitted helminths infection, taeniasis and intestinal protozoiasis were surveyed in 104 sites selected from 35 counties (districts) and the prevalence of clonorchiasis was surveyed in 62 sites selected from 37 townships. In each survey spot, 250 persons were surveyed. A total of 26 866 persons and 15 893 persons were surveyed. Modified Kato-Katz thick smear was used to detect the eggs of intestinal helminthes. Tube fecal culture was used to identify the species of hookworm. The Enterobius eggs were detected in children aged 3 to 6 years by using adhesive tape. The cyst and trophozoite of intestinal protozoa were examined with physiological saline direct smear method and iodine stain method. Results: The overall infestation rate of intestinal parasites was2.02% in Henan, and the worm infection rate was higher than protozoa infection rate. Fourteen kinds of intestinal parasites were found, including nematode (5 species), trematode (2 species), and protozoan (7 species). The infection rate of Enterobius vermicularis was highest, and Qinba Mountain ecological area had the highest infestation rate of intestinal parasites in 4 ecological areas of Henan. There was no significant difference in intestinal parasite infection rate between males and females (χ(2)=3.630, P=0.057), and the differences in intestinal parasite infection rate among different age groups had significance (χ(2)=124.783, P=0.000 1). The infection rate reached the peak in age group ≤9 years and the major parasite was Enterobius vermicularis. Furthermore the overall human infection rate of parasite showed a downward trend with the increase of educational level of the people (χ(2)=70.969, P=0.000 1), the differences had significance (χ(2)=120.118, P=0.000 1). For different populations, the infection rate of intestinal parasites was highest among preschool children. The infection of intestinal helminth was mainly mild, only 2 severe cases were detected. The infection rate of Clonorchis sinensis in urban residents was only 0.006%. Logistic regression analysis showed that being preschool children (χ(2)=15.765, P=0.000 1) and drinking well water (χ(2)=45.589, P=0.000 1) were the risk factors for intestinal parasite infection, and annual income per capita of farmers was the protective factor against intestinal parasite infection. The infection rates of protozoa and intestinal parasites decreased sharply compared with the results of previous two surveys, and the rate of intestinal helminth infection also dropped sharply compared with the second survey. The numbers of protozoa, helminth and intestinal parasites detected in this survey were all less than the numbers found in the previous two surveys. Conclusions: Compared the results of three surveys in Henan, the infection rate of protozoa and intestinal parasites showed a downward trend. The prevention and treatment of Enterobius vermicularis infection in children should be the key point of parasitic disease control in the future.

Prolonged parasite clearance in a Chinese splenectomized patient with falciparum malaria imported from Nigeria

Background

The spleen plays a pivotal role in the rapid clearance of parasitized red blood cells in patients with falciparum malaria after artemisinin treatment. Prolonged parasite clearance can be found in patients who have had a splenectomy, or those with hemoglobin abnormalities and/or reduced immunity, which are all distinguishable from artemisinin resistance. This paper reports on a case of prolonged parasite clearance in a Chinese splenectomized patient with falciparum malaria imported from Nigeria.

Case presentation

A 35-year-old Chinese male suffered 2 days of febrile illness after returning to Zhumadian city of Henan province from Nigeria on October 1, 2014. The main symptoms were febrile, including the highest axillary temperature of 40 °C, headache, and chills. A peripheral blood smear showed parasitemia (53 913 asexual parasites/μl) of Plasmodium falciparum. The patient had not used any chemoprophylaxis against malaria in Nigeria when he worked there as a construction worker between 2009 and 2014. The patient had three episodes of malaria in Nigeria and had a splenectomy due to a traffic accident 8 years ago from the time he was admitted to hospital. The patient was orally administrated a total of 320 mg/2.56 g dihydroartemisinin-piperaquine for 2 days and intravenously administrated a total of 3 000 mg artesunate for 18 days. The axillary temperature of the patient ranged between 37.0 and 37.7 °C from Day 0 to Day 3, and blood microscopy revealed falciparum malaria parasitemia (26 674 asexual parasites/μl) on Day 3. The patient was afebrile on Day 4, falciparum malaria parasitemia was continuously present and then gradually decreased on the next days, and was negative on Day 21. The patient was cured and left hospital on Day 24 after no plasmodium falciparum was found in the blood on Day 21 to Day 23. No mutation was found in the K13 propeller gene when compared with the PF3D7_1343700 K13 propeller gene reference sequence.

Conclusions

This is the first reported case in China of prolonged parasite clearance in a splenectomized patient with imported falciparum malaria. Artemisinin resistance should be distinguished when prolonged parasite clearance is found in a malaria patient who has had splenectomy.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0259-5) contains supplementary material, which is available to authorized users.

Characterization and Antibacterial Activity of Oil-In-Water Nano-Emulsion Formulation Against Candidatus Liberibacter asiaticus

Nano-emulsion is a promising delivery system for increasing pesticide use and enhancing the therapeutic efficiency against pathogens. The pathogen Candidatus Liberibacter asiaticus (Las) that causes destructive citrus huanglongbing (HLB) resides in citrus phloem, which makes it difficult to treat with chemicals. Based on various physiochemical characteristics of oils, surfactants, and organic solvents, an oil-in-water (O/W) nano-emulsion formulation was developed and optimized to combat citrus HLB. The nano-emulsion was formulated through a spontaneous emulsification method for efficient delivery of ampicillin into the citrus phloem using bark application. The nano-emulsion that was prepared from Cremophor EL (viscous oil), acetone (water miscibility organic solvent), and Span 80/Tween 80 (surfactant) formed a small droplet size (17.33 ± 0.52 nm) and exhibited an improved absorption rate. Peak concentration was detected at 2 days posttreatment and the maximum concentration (C_max) and relative bioavailability (RBA) of ampicillin in HLB-affected citrus were 71.86 ± 35.38 ng/g and 267.25% ± 44.1%, respectively. The peak concentration of Amp appeared at 6 days posttreatment in the citrus trees that were treated with Amp alone and their C_max and RBA were 56.44 ± 32.59 ng/g and 100%, respectively. The same nano-emulsion was used to deliver five different antimicrobials to control citrus HLB through bark application. We found that the droplet size of the antimicrobials in the nano-emulsion was significantly reduced and the nano-emulsion also enhanced the therapeutic efficiency of validoxylamine A alone and in combination with actidione as well as sulfadimoethoxine sodium against Las. Therefore, this study provides an efficient bark application nano-emulsion formulation for citrus HLB control.

Molecular mutation profile of pfcrt in Plasmodium falciparum isolates imported from Africa in Henan province

Background

Anti-malarial drug resistance is a primary public health problem. Haplotypes of pfcrt gene have been implicated to be molecular markers of chloroquine (CQ) resistance. This study aims to explore the prevalence of polymorphisms in pfcrt in Plasmodium falciparum-infected patients imported from Africa in Henan province.

Methods

Blood samples were collected from 502 patients who were infected with P. falciparum returning from Africa in Henan province during 2012–2015. The single nucleotide polymorphisms in pfcrt (codons 72–76) were assessed by nested PCR with DNA sequencing and restriction digestion, the haplotype prevalences were also determined.

Results

Four haplotypes coding 72–76 of pfcrt were found including CVMNK (wild type), CVIET (mutation type), CVIEK (mutation type), and CV M/I N/E/D/K K/T (mixed type), with 61.95 % (311/502), 33.07 % (166/502), 0.20 % (1/502), and 4.78 % (24/502) prevalence, respectively. Except mixed type, CVIET and CVIEK were the largest proportion of the mutant type in West Africa, accounting for 44.83 % (91/203), followed by East Africa (8/21, 38.10 %), North Africa (4/11, 36.36 %), Central Africa (36/135, 26.67 %), and South Africa (28/132, 21.21 %). There was significant difference among the groups (χ² = 23.78, P < 0.05). Mixed type was the largest proportion in North Africa (9.09 %), followed by Central Africa (6.67 %), East Africa (4.76 %), South Africa (4.55 %), and West Africa (3.45 %). There was no significant difference among the groups (χ² = 2.31, P > 0.05). The position 72 and 73 of pfcrt showed predominance for the wild type with rates of 100 % (502/502).

Conclusions

This study identified four haplotypes of pfcrt in P. falciparum-infected patients imported from Africa in Henan province. The prevalence of mutations in the pfcrt was dropped comparing with other people’s researches. It establishes fundamental data for detection of P. falciparum CQR with molecular markers for the imported P. falciparum in China, and it also provides complementary information of CQR for the malaria endemic countries and assesses the evolution of anti-malarial drug resistance.

Zinc treatment increases the titre of 'Candidatus Liberibacter asiaticus' in huanglongbing-affected citrus plants while affecting the bacterial microbiomes

AIMS

Huanglongbing (HLB)-affected citrus often display zinc deficiency symptoms. In this study, supplemental zinc was applied to citrus to determine its effect on Candidatus Liberibacter asiaticus (Las) titre, HLB symptoms, and leaf microbiome.

METHODS AND RESULTS

HLB-affected citrus were treated with various amounts of zinc. The treatments promoted Las growth and affected microbiomes in citrus leaves. Phylochip(™) -based results indicated that 5475 of over 50 000 known Operational Taxonomic Units (OTUs) in 52 phyla were detected in the midribs of HLB-affected citrus, of which Proteobacteria was the most abundant, followed by Firmicutes and Actinobacteria. In comparison, the microbiomes of zinc-treated diseased plants had overall more OTUs with higher amounts of Proteobacteria, but decreased percentages of Firmicutes and Actinobacteria. In addition, more OTUs of siderophore-producing bacteria were present. Only zinc-sensitive Staphylococcaceae had higher OTU's in the diseased plants without zinc treatments.

CONCLUSIONS

Although HLB-affected citrus appear zinc deficient, zinc amendments increased the pathogen levels and shifted the microbiome.

SIGNIFICANCE AND IMPACT OF THE STUDY

HLB is currently the most devastating disease of citrus worldwide. Zinc is often applied to HLB-affected citrus due to zinc deficiency symptoms. This study provided new insights into the potential effects of zinc on HLB and the microbial ecology of citrus.

Brassinosteroid (BR) biosynthetic gene lhdd10 controls late heading and plant height in rice (Oryza sativa L.)

A Brd2 allele suppresses heading date by altering the expression of heading date regulators such as OsMADS50 , and also negatively regulates chlorophyll biosynthesis. Heading date and plant height are important determinants of yield in rice (Oryza sativa L.). In this study, we characterized a late heading, dwarf mutant known as lhdd10 selected following ethyl methane sulfonate (EMS)-treatment of ssp. indica cultivar 93-11. lhdd10 showed late heading, dwarfness and slightly darker-green leaves than wild-type 93-11 under long-day and short-day conditions. We isolated lhdd10 by map-based cloning; it encoded a putative FAD-linked oxidoreductase protein (a brassinosteroid biosynthetic gene) that localized to the nucleus. LHDD10 was constitutively expressed in various tissues, but more so in shoot apices and panicles. Our data showed that lhdd10 influences heading date by controlling the expression of heading date regulators, such as OsMADS50 in both LD and SD conditions. lhdd10 also negatively regulated expression of chlorophyll biosynthetic genes to reduce the chlorophyll content. Our data indicated that BRs play important roles in regulating heading date and chlorophyll biosynthesis. This work provides material that will allow study of how BRs regulate heading date in rice.

Correlation of serum albumin with the clinical features and prognosis of preterm neonates in the neonatal intensive care unit

OBJECTIVE

To evaluate the clinical significance of serum albumin (ALB) levels in the early evaluation and prognosis of preterm infants in the neonatal intensive care units (NICUs).

MATERIALS AND METHODS

The authors collected and retrospectively analyzed complete clinical records of preterm infants admitted to the NICU from July 2012 to March 2013. The cases were divided into three groups according to their ALB levels: ≥ 30 g/L, 25-30 g/L, and ≤ 25 g/L.

RESULTS

The mean gestational age in the ≤ 25 g/L ALB group was significantly higher than that in the ≥ 30 g/L ALB group [(33.41 ± 2.15) weeks] (p < 0.05). The prealbumin, blood platelet, and blood urea nitrogen in the ≤ 25 g/L ALB group were significantly lower than those in the ≥ 30 g/L ALB group (p < 0.05). In addition, serum lactate in the ≤ 25 g/L ALB group was significantly higher than that in the ≥ 30 g/L ALB group (p < 0.05).

CONCLUSION

Serum ALB level increased with increasing gestational age. Lower ALB levels were associated with more perinatal complications, damage to multiple organs, more severe cases, and mechanical ventilation, which resulted in longer hospital stays and poorer prognoses.

Plumbagin shows anti-cancer activity in human breast cancer cells by the upregulation of p53 and p21 and suppression of G1 cell cycle regulators

PURPOSE

Plumbagin, a naphthoquinone constituent of Plumbago zeylanica L. (Plumbaginaceae), is known to exhibit proapoptotic, antiangiogenic and antimetastatic effects in cancer cells. However, the effect of Plumbagin on breast cancer cells and the underlying molecular mechanism has not yet been elucidated.

MATERIALS AND METHODS

MCF-7 (a human breast cancer cell line) was exposed different concentrations of Plumbagin (PG), and the anti-proliferative activity was evaluated by the MTT assay. The mechanism of action for the growth inhibitory activity of Plumbagin on MCF-7 cancer cells was evaluated using flow cytometry for cell cycle distribution, and western blot for assessment of expression of potential target proteins.

RESULTS

Plumbagin exhibited a significant anti-proliferative activity against human breast cancer cells. Flow cytometric analysis revealed that Plumbagin caused cell cycle arrest at G1 phase. The cell cycle arrest was well correlated with the inhibition of cyclin D1, cyclin E, and upregulation of tumor suppressor protein p53. It further inhibited the expression of anti-apoptotic Bcl-2 family members such as Bcl-xL and Bcl-2, and activated pro-apoptotic proteins like Bax and Bak.

CONCLUSION

These findings suggest that the anti-proliferative effect of Plumbagin is due to upregulation of p53 and p21 and suppression of G1 cell cycle regulators.

Diffraction model for thermoreflectance data

Thermoreflectance imaging provides the capability to map temperature spatially on the submicrometer scale by using a light source and CCD camera for data acquisition. The ability to achieve such spatial resolution and observe detailed features is influenced by optical diffraction. By combining diffraction from both the sample and substrate, a model is developed to determine the intensity of the thermoreflectance signal. This model takes into account the effective optical distance, sample width, wavelength, signal phase shift, and reflectance intensity, while showing qualitative and quantitative agreement with experimental thermoreflectance images from 1 and 10 μm wide gold lines at two wavelengths.

Fabrication of 3D photonic components on bulk crystalline silicon

We have fabricated three dimensional photonic components such as waveguides and beam splitters from crystalline silicon using a process based on one or more ion irradiation steps with different energies and fluences, followed by electrochemical anodization and thermal annealing. We first demonstrate the fabrication of multilevel silicon waveguides and then extend this process to make multilevel beam splitters, in which three output waveguides are distributed over two depths. The dimensions of the waveguides can be defined within a range from 0.5 μm to several micrometers simply by varying the ion beam fluence.

Isolated familial pneumothorax in a Taiwanese family with Birt-Hogg-Dubé syndrome

Primary spontaneous pneumothorax usually occurs as a sporadic event, but may be clustered in certain families with an underlying inherited disorder. Birt-Hogg-Dubι (BHD) syndrome is a rare autosomal dominant disease accounting for familial pneumothorax. BHD syndrome, caused by mutation of the folliculin gene, is characterized by skin fibrofolliculoma, pulmonary cysts, pneumothorax, and renal cancer. We describe a BHD-affected Taiwanese family with clinical and genetic study. A rare mutation of the folliculin gene was detected in the patient and members with pulmonary cysts or pneumothorax, but no skin or renal lesions were found. This mutation was reported in a Taiwanese family and might indicate a pneumothorax-predominant phenotype. Isolated pneumothorax is an uncommon initial presentation of BHD syndrome. Family history should be carefully reviewed when managing a patient with pneumothorax.

Training effects of a 12-week walking program on Parkinson disease patients and community-dwelling older adults

BACKGROUND

Introducing evidence-based exercise guidelines of Parkinson's disease (PD) into clinical practice and community settings has been highlighted.

AIM

This study tested the feasibility and compared the weekly effects of a 12-week walking training program on PD patients and community-dwelling seniors.

DESIGN

A prospective quasi-experimental design was used. PD patients in Hoehn and Yahr Stage I through III (PG) and community-dwelling adults older than 65 were recruited (CG).

METHODS

In the outpatient department of a hospital, the information of personal data, coordination test, and walking ability of participants were collected first. They then participated in a 36-session, 12-week treadmill walking training program.

RESULTS

Weekly data of step length and velocity in PG and CG were collected. The walking training program achieved significant velocity (χ² = 126.38, p < 0.001) and step length (χ² = 27.27, p = 0.001) improvements in PG. Differences in improvement between PG and CG in terms of velocity (χ² = 7.089, df = 1, p = 0.008) and step length (χ² = 7.718, df = 1, p = 0.005) were also identified.

CONCLUSION

The applicability of this 12-week walking program both for PD patients and community-dwelling older adults was identified. Conducting the economic evaluation and neurology studies of the 12-week walking program and test the effects of five-week walking program are suggested.

[Assessment of malaria knowledge and capability on Plasmodium detection among professionals from class III malaria-endemic counties of Henan Province in 2012]

OBJECTIVE

To evaluate the capability of malaria parasite detection among professionals from Class III malaria endemic counties of Henan Province in 2012. METHEDS: The capacity assessment of professionals from the Centres for Disease Control and the medical institutions was done in September to December 2012. The content of the assessment included malaria knowledge (including malaria etiology, clinical manifestation, diagnosis, treatment and epidemiology and so on, 100 scores as full marks and 60 as passing score), making blood slides of Plasmodium (4 slides in 1 hour, including Giemsa staining, 40 scores as full marks and 24 as passing score) and identification of species with microscopy (6 slides, 8 min per slide 60 scores as full marks and 36 as passing score). All the participanats were grouped by gender, age, professional title, level and type of institution. Their scores were statistically analyzed by SSPS 17.0 software.

RESULTS

The average total score in 891 participants was 162.1, the highest was 200 (full markers), and the lowest was 96, and 871 (97.8%) participants passed the test (> or = 120 scores). There were no significant differences for the scores of blood slide making among gender, age, professional title and level of institution (P > 0.05). No significant differences in the scores of malaria knowledge and blood slide reading among gender female participants (162.97 +/- 17.64) was higher than that of males (159.01 +/- 20.33) (P < 0.05). The film-reading and total scores of 50-plus age group (34.62 +/- 14.82, 144.62 +/- 20.33) was significantly lower than the other three groups (under age 30 group: 45.75 +/- 13.58 and 162.50 +/- 18.90, age 31-40 group: 46.53 +/- 12.72 and 163.51 +/- 17.77, age 41-50 group: 46.22 +/- 13.38 and 159.80 +/- 17.32) (P < 0.05). The scores of malaria knowledge in 50-plus age group (84.38 +/- 9.41) was lower than that of under age 30 group (89.91 +/- 7.81), age 31-40 group (89.96 +/- 7.74) (P < 0.05). The scores of malaria knowledge (88.33 +/- 8.23, 90.00 +/- 7.76, 92.37 +/- 7.29), film-reading (44.88 +/- 13.62, 46.59 +/- 12.88, 49.57 +/- 11.98) and total scores (159.61 +/- 18.37, 163.81 +/- 18.03, 169.15 +/- 16.38) of primary, intermediate and senior groups was proportional to the level of the titles, and the difference between the groups was statistically significant (P< 0.05). The theory (88.28 +/- 8.30, 90.84 +/- 7.32, 93.54 +/- 6.10), film-reading (44.54 +/- 13.14, 47.69 +/- 13.40, 52.62 +/- 11.04) and total scores (159.48 +/- 18.33, 165.92 +/- 17.31, 171.97 +/- 15.53) of the three institution level groups (township, county and province) were proportional to their level, and the difference between the groups was statistically significant (P < 0.05). There was no significant differences for the scores between the CDCs and hospitals (P < 0.05).

CONCLUSION

The capabilities of malaria parasite detection in Class III malaria endemic counties of Henan Province is balanced. It needs to strengthen the skills training for the professionals of the junior, intermediate and primary care units.

Cryopreservation of germinal vesicle stage porcine oocytes based on intracellular ice formation assessment

This study aimed at evaluating the feasibility of slow freezing for cryopreservation of germinal vesicle (GV) stage porcine oocytes. In this study, intracellular ice formation (IIF) characteristics of GV porcine oocytes were investigated by using a thermoelectric cooling (TEC) cryomicroscope system. This cryomicroscope system used a thermoelectric cooling (TEC) chip in its cold stage as a heat sink and employed a PID control algorithm to achieve accurate temperature control. The temperature was controlled to a range between 70 degree C and -55 degree C with an accuracy of +/- 0.5 degree C. Five constant cooling rates of 24, 12, 6, 3 and 1.5 degree C/min were tested in experiments in freezing GV porcine oocytes from 20 degree C to -50 degree C in an NCSU-23 medium plus 2.0 M DMSO. The IIF temperature of each individual oocyte was recorded and cumulative IIF probabilities were calculated for each cooling rate. The total cumulative probabilities of IIF temperature distribution were 100 percent, 100 percent, 50.0 percent, 54.3 percent and 58.6 percent at cooling rates of 24, 12, 6, 3 and 1.5 degree C/min, respectively. A Weibull distribution model was found to adequately describe the distribution of IIF temperatures of GV porcine oocytes for the cooling rates tested (R2 = 0.858 +/- 0.09). The IIF experimental results indicate that cooling rates of 6, 3 and 1.5°C/min could be considered as possible cryopreservation protocols. Further experiments were performed to examine the feasibility of using these protocols to cryopreserve GV porcine oocytes. After 44 h of in-vitro maturation in NCSU-23, the survival of thawed oocytes was checked. Porcine oocytes developed from the GV stage to the MII stage by using Hoechst 33258 staining, followed by Lacmoid staining as a secondary check. Normalized survival rates of 37.7 +/- 4.6 percent, 45.0 4.4 percent and 45.4 +/- 5.9 percent were obtained for GV oocytes frozen at 1.5, 3 and 6 degree C/min, respectively. The experimental results indicate that slow freezing is a feasible approach for cryopreservation of GV porcine oocytes when cooling rate is properly selected. This study also demonstrated an efficient approach for investigating optimal cooling rates by assessing the IIF characteristics of GV porcine COCs.

Cloning and sequencing of the rDNA gene family of the water buffalo (Bubalus bubalis)

The rDNA genes coding for ribosomal RNA in animals are complicated repeat sequences with high GC content. We amplified water buffalo rDNA gene sequences with the long and accurate (LA) PCR method, using LA Taq DNA polymerase and GC buffer, based on bioinformatic analysis of related organisms. The rDNA genes were found to consist of 9016 nucleotides, including three rRNA genes and two internal transcribed spacers (ITS), which we named 18S rRNA, ITS1, 5.8S rRNA, ITS2 and 28S rRNA. We tested and optimized conditions for cloning these complicated rDNA sequences, including specific rules of primer design, improvements in the reaction system, and selection of the DNA polymerase.

An inter-subspecies cloned buffalo (Bubalus bubalis) obtained by transferring of cryopreserved embryos via somatic cell nuclear transfer

The aim of this study was to explore the feasibility of cryopreservation of inter-subspecies cloned embryos in buffalo. In our experiment, river buffalo ear fibroblast nucleus was fused into swamp buffalo oocyte cytoplasm. The blastocyst formation rate for nuclear transfer of freshly thawed cells was not different from those of growing cells, confluent or serum-starved cells. A total of 122 cloned blastocysts derived from cryopreserved fibroblasts were cryopreserved and thawed, 37 were survived, the cryosurvival rate was 30.3%. The survived blastocysts were transferred into 15 recipient buffalos. Five of the recipients established pregnancy, but four of them aborted on day 53, 59, 145 and 179 of gestation respectively. One cross-bred buffalo (Murrah × Swamp buffalo (2n = 49) received three embryos delivered a 40.5 kg female calf by natural delivery on day 320 of gestation. Up to now (13-month old), the cloned calf has been growing well with no abnormity observed. These results demonstrated that cryopreservation of inter-subspecies cloned embryos is feasible to produce buffalo offspring.