Clinical epidemiology and outcome of HIV-associated talaromycosis in Guangdong, China, during 2011-2017

OBJECTIVES

Talaromycosis is an invasive mycosis endemic to Southeast Asia. This study aimed to investigate the epidemiology, clinical features and prognostic factors of HIV-associated talaromycosis in Guangdong, China.

METHODS

We retrospectively evaluated HIV patients hospitalized with histopathology- or culture-confirmed talaromycosis between 2011 and 2017. Factors associated with poor prognosis were identified using logistic regression.

RESULTS

Overall, 1079 patients with HIV-associated talaromycosis were evaluated. Both the number and prevalence of talaromycosis among HIV admissions increased from 125 and 15.7% in 2011 to 253 and 18.8% in 2017, respectively, reflecting the increase in HIV admissions. Annual admissions peaked during the rainy season between March and August. Common clinical manifestations included fever (85.6%), peripheral lymphadenopathy (72.3%), respiratory symptoms (60.8%), weight loss (49.8%), skin lesions (44.5%) and gastrointestinal symptoms (44.3%). Common laboratory abnormalities were hypoalbuminaemia (98.6%), anaemia (95.6%), elevated aspartate aminotransferase level (AST) (76.9%), elevated alkaline phosphatase level (55.8%) and thrombocytopenia (53.7%). The median CD4 count was 9 cells/μL. Talaromyces marneffei was isolated from blood and bone marrow cultures of 66.6% and 74.5% of patients, respectively. The rate increased to 86.6% when both cultures were performed concurrently. At discharge, 14% of patients showed worsening conditions or died. Leucocytosis, thrombocytopenia, elevated AST, total bilirubin, creatinine and azole monotherapy independently predicted poor prognosis.

CONCLUSIONS

The incidence of HIV-associated talaromycosis has increased in Guangdong with the high HIV burden in China. Skin lesions were seen in less than half of patients. Induction therapy with azole alone is associated with higher mortality. Findings from this study should help to improve treatment of the disease.

[Textual research on the birthplace of Chen Xunzhai, a doctor of the Republic of China]

Chen Xunzhai was a famous Fujian traditional Chinese medicine expert in the period of the Republic of China. There are different records of his native place in the existing literature. By reviewing the published journals and books, interviewing Chen Xunzhai's scattered works and genealogy and visiting his descendants, this article conducted investigations and researches and confirmed that Chen Xunzhai, also named Guangcheng, was born in Shangyang Village, Gaopo Town in Yongding County of Fujian Province. He was the 22nd generation of descendants of Chen family in Shangyang Yingchuan County, not the descendant of the Chen family in Jiang Tian Nanyang of Chang Le City. Neither was he the seventh-generation grandson of Chen Xiuyuan. The findings of this paper will lay the foundation for the further researches on Chen Xunzhai.

[Real-world efficacy and safety of lopinavir/ritonavir and arbidol in treating with COVID-19 : an observational cohort study]

Objective: To evaluate the efficacy and safety of lopinavir/ritonavir (LPV/r) and arbidol in the treatment of COVID-19 in the real world. Methods: The clinical data of 178 patients diagnosed with COVID-19 admitted to Guangzhou Eighth People's Hospital were retrospectively analyzed from January 21 to February 9, 2020. According to the patient's antiviral treatment regimen, 178 patients were divided into 4 groups including LPV/r group (59 patients), arbidol group (36 patients), combination therapy with LPV/r plus arbidol group (25 patients) and the conventional treatment group without any antiviral drugs (58 patients). The main observation end points of the study was the negative conversion time of nucleic acid of the novel coronavirus (2019-nCoV) in pharyngeal swab. Results: The baseline of 4 groups before treatment was consistent and comparable. The negative conversion time of nucleic acid of the 2019-nCoV in pharyngeal swab was (10.20 ± 3.49), (10.11 ± 4.68), (10.86 ± 4.74), (8.44 ± 3.51) days separately in the LPV/r group, the arbidol group, the combination therapy group, and the conventional treatment group without significant difference (F = 2.556, P = 0.058). There was also no significant difference in the rate of negative conversion rate of 2019-nCoV nucleic acid, the improvement ration in clinical symptoms, and the improvement ration of pulmonary infection in the lung CT imaging (P> 0.05). However, a statistically significant difference was found in the proportion of deterioration changing from mild/moderate to severe/critical type at day 7 (χ(2) = 9.311, P = 0.017) as follows: the combination therapy group (24.0%, 6/25), the arbidol group ( 16.7%, 6/36), LPV/r group (5.4%, 3/56) and conventional treatment group (5.2%, 3/58). Moreover, the frequency of adverse reactions in the three groups receiving antiviral drugs was significantly higher than that in the conventional treatment group (χ(2) = 14.875, P = 0.002). Conclusions: No evidences could prove that LPV/r and arbidol could shorten the negative conversion time of novel coronavirus nucleic acid in pharyngeal swab nor improve the symptoms of patients. Furthermore, the combination usage of LPV/r and arbidol may not benefit for improving the disease. Noteworthy, the adverse reactions of the antiviral drugs should be paid careful attention during the treatment.

[Impact of water body environments on the microbial community of Oncomelania hupensis snails in marshlands around the eastern Dongting Lake]

OBJECTIVE

To evaluate the effects of water body environments on the microbial community of Oncomelania hupensis snails in marshlands of the eastern Dongting Lake where natural extinction of O. hupensis snails are found, so as to explore the correlation between the natural extinction of O. hupensis snails and the microbial community in snails.

METHODS

Snails were caged water bodies in the Qianliang Lake marshland (Qianliang Lake regions) where natural extinction of snails was found and in the Junshan Park marshland (Junshan Park regions) in the eastern Dongting Lake for 30 days, and then all snails were collected and identified for survival or death. DNA sequencing of the fungi and bacteria was performed in snails before and after immersion in waters, and the biodiversity and abundance were analyzed.

RESULTS

The survival rates of O. hupensis snails were 28.0% (70/250) and 64.8% (162/250) in Qianliang Lake regions and Junshan Park regions 30 days after immersion in waters, respectively (χ² = 81.365, P < 0.01). The number of the fungal community and the biodiversity of the bacterial community were both greater in snails caged in Qianliang Lake regions post-immersion than pre-immersion, and there was a significant difference in the structure of the fungal and bacterial communities. The microbial community with a significant difference included Flavobacteriaceae,which was harmful to O. hupensis snails.

CONCLUSIONS

The water body environment affects the composition of the microbial community in O. hupensis snails in marshlands with natural snail distinction around the eastern Dongting Lake; however, further studies are required to investigate whether the natural distinction of snails is caused by water body environments-induced changes of the microbial spectrum in O. hupensis snails.

Terahertz photonic integrated circuit for frequency tuning and power modulation

The quantum cascade laser is a powerful solid-state source of terahertz-frequency radiation. However, integrating multiple photonic functions into a monolithic platform in this frequency range is non-trivial due to the scaling of photonic structures for the long terahertz wavelengths and the low frequency tuning coefficients of the quantum cascade lasers. Here, we have designed a simple terahertz-frequency photonic integrated circuit by coupling a racetrack resonator with a ridge laser in the longitudinal direction to design a notch filter. The transmission properties of this filter structure are dependent on the phase matching and losses in the coupled racetrack and results in a comb of stopband frequencies. We have optimized the comb separation by carefully selecting the cavity dimensions of the racetrack resonator to suppress longitudinal modes in the ridge laser enabling single-mode emission. The emission frequencies and output power from laser are controlled through appropriate control of drive currents to the ridge and the racetrack resonator. The emission frequency is electrically tuned over ∼81 GHz exploiting Stark shift of the gain as a function of drive current at the ridge laser, coinciding with an output power variation of ∼27% of the peak power (at a heat sink temperature of 50 K). The output power from the ridge also varied by ∼30% and the frequency was tuned by a further 10 GHz when the driving conditions at the ridge laser are invariant and the current at the racetrack resonator was varied. To our best knowledge, this is the first report of a frequency engineering, tuning and power modulation of terahertz-frequency quantum cascade lasers using a photonic integrated circuit.

Detection of novel piroplasmid species and Babesia microti and Theileria orientalis genotypes in hard ticks from Tengchong County, Southwest China

To reveal the genetic diversity of Babesia microti and Theileria orientalis in Southwest China, we conducted a molecular survey of piroplasms in hard ticks in a China-Myanmar border county. Host infesting and questing ticks were collected from Tengchong County in 2013 and 2014. Piroplasm infection in ticks was detected by PCR, and then, phylogenetic analysis was conducted to study the genetic diversity of the pathogens identified in ticks. All in all, six piroplasm species comprising of B. microti; B. orientalis; a novel Babesia species designated Babesia sp. Tengchong, China; T. orientalis; T. luwenshuni; and an as yet undescribed piroplasmid species referred to as Piroplasmid sp. Tengchong, China, have been identified after screening goat- and cattle-attached ticks. In addition, B. bigemina has been identified by screening questing ticks. Phylogenetic analysis based on the 18S rRNA and partial β-tubulin gene revealed two novel potentially zoonotic genotypes designated B. microti Tengchong-Type A and B. The T. orientalis genotypes identified in the present study represent the seven known genotypes 1-5, 7, and N3 as revealed by phylogenetic analysis of 18S rRNA and MPSP genes. Importantly, an additional genotype designated N4 has also been identified in this study, which brings the number of recognized T. orientalis genotypes to a total of twelve. Thus, besides the two novel species, Babesia sp. Tengchong, China, closely related to Babesia species isolated from yak and Piroplasmid sp. Tengchong, China, our study demonstrates that additional novel B. microti and T. orientalis genotypes exist in Southwest China.

Spatial structure of the microbiome in the gut of Pomacea canaliculata

Background

Gut microbes can contribute to their hosts in food digestion, nutrient absorption, and inhibiting the growth of pathogens. However, only limited studies have focused on the gut microbiota of freshwater snails. Pomacea canaliculata is considered one of the worst invasive alien species in the world. Elucidating the diversity and composition of the microbiota in the gut of P. canaliculata snails may be helpful for better understanding the widespread invasion of this snail species. In this study, the buccal masses, stomachs, and intestines were isolated from seven P. canaliculata snails. The diversity and composition of the microbiota in the three gut sections were then investigated based on high-throughput Illumina sequencing targeting the V3-V4 regions of the 16S rRNA gene.

Results

The diversity of the microbiota was highest in the intestine but lowest in the buccal mass. A total of 29 phyla and 111 genera of bacteria were identified in all of the samples. In general, Ochrobactrum, a genus of putative cellulose-degrading bacteria, was the most abundant (overall relative abundance: 13.6%), followed by Sediminibacterium (9.7%), Desulfovibrio (7.8%), an unclassified genus in the family Aeromonadaceae (5.4%), and Cloacibacterium (5.4%). The composition of the microbiota was diverse among the different gut sections. Ochrobactrum (relative abundance: 23.15% ± 7.92%) and Sediminibacterium (16.95 ± 5.70%) were most abundant in the stomach, an unclassified genus in the family Porphyromonadaceae (14.28 ± 7.29%) and Leptotrichia (8.70 ± 4.46%) were highest in the buccal mass, and two genera in the families Aeromonadaceae (7.55 ± 4.53%) and Mollicutes (13.47 ± 13.03%) were highest in the intestine.

Conclusions

The diversity and composition of the microbiome vary among different gut sections of P. canaliculata snails. Putative cellulose-degrading bacteria are enriched in the gut of P. canaliculata.

Tunable broadband terahertz polarizer using graphene-metal hybrid metasurface

We demonstrate an electrically tunable polarizer for terahertz (THz) frequency electromagnetic waves formed from a hybrid graphene-metal metasurface. Broadband (>3 THz) polarization-dependent modulation of THz transmission is demonstrated as a function of the graphene conductivity for various wire grid geometries, each tuned by gating using an overlaid ion gel. We show a strong enhancement of modulation (up to ∼17 times) compared to graphene wire grids in the frequency range of 0.2-2.5 THz upon introduction of the metallic elements. Theoretical calculations, considering both plasmonic coupling and Drude absorption, are in good agreement with our experimental findings.

Increasing the sensitivity of terahertz split ring resonator metamaterials for dielectric sensing by localized substrate etching

We demonstrate a significant enhancement in the sensitivity of split ring resonator terahertz metamaterial dielectric sensors by the introduction of etched trenches into their inductive-capacitive gap area, both through finite element simulations and in experiments performed using terahertz time-domain spectroscopy. The enhanced sensitivity is demonstrated by observation of an increased frequency shift in response to overlaid dielectric material of thicknesses up to 18 µm deposited on to the sensor surface. We show that sensitivity to the dielectric is enhanced by a factor of up to ∼2.7 times by the incorporation of locally etched trenches with a depth of ∼3.4 µm, for example, and discuss the effect of the etching on the electrical properties of the sensors. Our experimental findings are in good agreement with simulations of the sensors obtained using finite element methods.

Detection sensitivity of laser feedback interferometry using a terahertz quantum cascade laser

We report on the high detection sensitivity of a laser feedback interferometry scheme based on a terahertz frequency quantum cascade laser (QCL). We show that variations on the laser voltage induced by optical feedback to the laser can be resolved with the reinjection of powers as low as ∼-125  dB of the emitted power. Our measurements demonstrate a noise equivalent power of ∼1.4  pW/√Hz, although, after accounting for the reinjection losses, we estimate that this corresponds to only ∼1  fW/√Hz being coupled to the QCL active region.

[Research on the causes of death associated with combined effects of HBV and HCV infection in patients with acquired immunodeficiency syndrome]

Objective: To investigate the combined effects of hepatitis B virus and hepatitis C virus (HBV/HCV) infection on the cause of death in patients with acquired immunodeficiency syndrome (AIDS). Methods: The causes of death of 111 cases of AIDS with HBV/HCV (combined infection group) and 210 AIDS patients (single infection group) admitted to our hospital from 2012 to 2016 data were compared using chi-square test. Results: There was no statistically significant difference in gender composition and age in the combined infection groups (P > 0.05). The main causes of death in the combined infection group were severe pneumonia (44.1%), end-stage liver disease (18.9%), and central nervous system infection (14.4%). The main causes of death in the single infection group were severe pneumonia (47.6%) and central nervous system infection (14.3%) and tumor (13.3%). There was no case of end-stage liver disease. The ratio of end-stage liver disease in the former group was significantly higher than that in the latter group (χ(2) = 42.511, P < 0.001). The main cause of death in 12 HIV/HBV/HCV triple-infected patients was end-stage liver disease, accounting for 41.7%, which was significantly higher than 18.9% of end-stage liver disease in HIV/HBV or HIV/HCV dual infection (99 cases). And the difference was statistically significant (χ(2) = 4.539, P = 0.033); however, the ratio of end-stage liver disease in 50 HIV/HBV co-infected patients and 49 HIV/HCV co-infected patients was 16.0% vs. 16.3%, respectively, and the difference was not statistically significant (χ(2) = 0.002, P = 0.965). In the co-infected group, 36 patients had CD4(+) cell counts >100/μl, the primary cause of death was end-stage liver disease, accounting for 38.2%. 75 patients with CD4(+) ≤ 100/μl died due to end-stage liver disease, accounting for 9.3% and the difference was statistically significant (χ(2) = 13.852, P < 0.05). Conclusion: End-stage liver disease is the main cause of death in patients with AIDS combined with HBV or HCV, especially triplet infection and CD4(+) cell count > 100/μl. An early diagnosis and treatment of HBV or HCV infection should commence as soon as possible.

[Discussion on optimal duration of pegylated interferon α combined with ribavirin for chronic hepatitis C in HIV-infected patients]

Objective: To investigate the optimal duration of pegylated-alpha interferon (Peg-INFα) combined with ribavirin (RBV) in treating chronic hepatitis C infection in human immunodeficiency virus (HIV)-infected patients. Methods: A multicenter prospective study was conducted. The study subjects were divided into two groups; HIV/HCV co-infections (Group A, n = 158) and control with HCV-monoinfections (Group B, n = 60). All recruited patients received standard Peg-INFα plus RBV therapy. Group A was divided into 3 subgroups according to CD4(+) cell counts: A1 subgroup, 79 cases, CD4(+) counts > 350 cells /μl, who received anti-HCV before combination antiretroviral therapy(cART); A2 subgroup, 45 cases, CD4(+) counts between 200 and 350 cells/μl, who did not start anti-HCV until they could tolerate cART well; A3 subgroup, 34 cases, CD4(+) counts < 200 cells /μl, cART was administered first, and anti-HCV therapy was started when CD4(+) counts > 200 cells/μl. The anti-HCV efficacy of two groups and 3 subgroups were compared. Statistical analysis for normal distribution and homogeneity of variance data was calculated by t-test and the counting data was analyzed by χ (2) test. The Mann-Whitney U test was used for non-normal data. A one-way analysis of variance (ANOVA) was used for the comparison of multiple groups, followed by SNK method. Multiple independent samples were used for non-parametric tests. Results: There was no significant difference in age and baseline HCV RNA levels between groups and subgroups (P > 0.05). By an intent-to-treat (ITT) analysis, in Group A, the ratio of complete early virological response (cEVR) rate was 75.3% (119/158), the ratio of end of treatment virological response (eTVR) rate was 68.4% (108/158), and the ratio of sustained virological response (SVR) rate was 48.7% (77/158); in Group B, the ratio of cEVR rate was 93.3% (56/60), the ratio of eTVR rate was 90.0% (54/60), and the ratio of SVR rate was 71.7% (43/60); The therapeutic index of Group A were lower than those of Group B (P≤0.05). By per-protocol (PP) analysis, the ratio of cEVR rate in Group A [75.2% (88/112)] was still lower than that in Group B [93.3% (56/60)], but no significant differences were found in the ratio of eTVR rate and SVR rate between 2 groups (P > 0.05). Comparing the efficacy of subgroups (A1, A2 and A3) by ITT analysis, the ratios of cEVR rate were respectively 78.5% (62/79), 75.6% (34/45) and 67.6% (23/34); the ratios of eTVR rate were respectively 68.4%(54/79), 80.0%(36/45)and 52.9%(18/34); and the ratios of SVR rate were respectively 41.8%(33/79), 64.4%(29/45)and 44.1%(15/34). The ratio of eTVR in subgroup A2 was obviously higher than that in subgroup A3 and the ratio of SVR in subgroup A2 was statistically higher than that of subgroup A1(P≤0.05). However, by PP analysis, no significant differences of the therapeutic indexes were found among the respective subgroups (P > 0.05). Conclusion: HIV-HCV co-infected patients would have better anti-HCV efficacy with Peg-INFα-2a plus RBV than HCV- monoinfected patients. The best time for initiating anti-HCV therapy in HIV-HCV co-infected patients is when CD4(+) counts 200 cells/ μl.

Expression of Mucin 1 in salivary gland tumors and its correlation with clinicopathological factors

This study aimed to detect the expression of Mucin 1 (MUC1) in acinic cell carcinoma (AciCC) of salivary gland and to explore the relationship between MUC1 and clinicopathological factors of AciCC of salivary gland. Patients with salivary gland tumors who were treated at our hospital were enrolled in this study. The pathological sections collected from all subjects were classified by histological examinations. In addition, 40 cases of primary salivary gland AciCC tissues were selected and classified into experimental group, whereas 40 cases of normal salivary gland (NSG) tissues were selected and classified into control group. MUC1 positive cells in both experimental and control groups were detected by immunohistochemistry assays, while all clinical data were analyzed statistically. The results showed that MUC1 was only expressed in the ductal epithelium of NSG and distributed at the apical side of the cell membrane. In primary salivary gland AciCC tissues, scattered expressions of MUC1 were found both on the cell membrane and in the cytoplasm of tumor cells, and sometimes even in the cell nuclei, thus completely eliminating the polarized distribution of MUC1 expressions. The percentage of MUC1 positive cells in experimental group was significantly higher than that in control group (P < 0.05). In addition, the expression of MUC1 in salivary gland AciCC was correlated with gender, age, histological type, lesion location, cervical lymph node metastasis, local recurrence, and distant metastasis. In conclusion, MUC1 is related to the occurrence and development of salivary gland AciCC. Therefore, MUC1 may be used as a novel tumor marker in the clinical diagnosis and treatment of salivary gland AciCC.

Gas spectroscopy through multimode self-mixing in a double-metal terahertz quantum cascade laser

A multimode self-mixing terahertz-frequency gas absorption spectroscopy is demonstrated based on a quantum cascade laser. A double-metal device configuration is used to expand the laser's frequency tuning range, and a precision-micromachined external waveguide module is used to enhance the optical feedback. Methanol spectra are measured using two laser modes at 3.362 and 3.428 THz, simultaneously, with more than eight absorption peaks resolved over a 17 GHz bandwidth, which provide the noise-equivalent absorption sensitivity of 1.20×10^-3  cm^-1 Hz^-1/2 and 2.08×10^-3  cm^-1 Hz^-1/2, respectively. In contrast to all previous self-mixing spectroscopy, our multimode technique expands the sensing bandwidth and duty cycle significantly.

[Effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury]

Objective: To investigate the effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury. Methods: Forty-two rabbits were randomly divided into 7 groups (n=6 each), group A (saline control group), group B (penicillin group), group C (low dose erythromycin group), group D (low dose erythromycin and penicillin group), group E (budesonide group), group F (low dose erythromycin and budesonide group), group G (low dose erythromycin, penicillin and budesonide group). All rabbits received tracheotomy, and the tracheal mucosa was scraped with a nylon brush 20 times for tracheal stenosis model. Rabbits were treated with corresponding drugs from a week before operation to 9 days after operation. The serum concentrations of transforming growth factor - beta 1 (TGF-β(1)), vascular endothelial growth factor (VEGF), interleukin (IL) -6, IL-8 were determined and the tracheal specimens were harvested for measuring degree of stenosis on the 10th day after operation. Results: Serum concentrations of TGF-β(1) in group A, B, C, D, E, F and G were (17.6±1.3), (18.2±3.1), (13.0±1.1), (14.0±1.0), (21.0±6.1), (13.6± 3.5), (8.2±1.3) ng/L; VEGF were (88.1±4.1), (85.8±4.3), (58.1±6.3), (56.5±2.4), (87.8±2.8), (57.0±3.7), (34.3±6.7) ng/L; IL-6 were (67.8±4.0), (66.1±3.5), (54.1±4.8), (52.1±3.2), (64.6±4.9), (49.4±4.2), (35.9±3.7) ng/L; IL-8 were (112.8±5.2), (116.6±4.1), (88.0±6.2), (85.5±3.5), (114.4±4.6), (82.6±3.8), (55.9±6.0) ng/L, respectively. The serum concentrations of TGF-β(1), VEGF, IL-6 and IL-8 in group C, D, F and G were significantly lower than those in group A, B and E (all P<0.05). Compared with the other groups, the serum concentrations in group G were the lowest (all P<0.05). All 42 rabbits had tracheal stenosis with different degrees of proliferation of granulation tissue. The degree of tracheal stenosis in Group A, B, C, D, E, F and G were (53.3±4.4)%, (48.2±5.0)%, (24.3±4.4)%, (29.5±3.2)%, (47.8±6.5)%, (27.9±3.1)%, (15.6±2.0)%, respectively. The degree of tracheal stenosis in group C, D, F and G was significantly lower than that in group A, B and E, which had statistical differences (all P<0.05). Compared with the other groups, the degree of tracheal stenosis in group G was the lowest (all P<0.05). Conclusions: Low dose of erythromycin can effectively inhibit the proliferation of granulation tissue after tracheal injury in rabbits. And it has better effectiveness when combined with other antibiotics and hormone.

Endosymbionts Alter Larva-to-Nymph Transstadial Transmission of Babesia microti in Rhipicephalus haemaphysaloides Ticks

Maternally inherited endosymbionts inhabit a variety of arthropods. Some of them can protect the arthropod host against a wide range of pathogens. However, very little is known about the association between endosymbionts and pathogen susceptibility in ticks. The present study investigated the effect of endosymbionts on larva-to-nymph transstadial transmission of Babesia microti by Rhipicephalus haemaphysaloides ticks. Engorged female ticks were injected with PBS, ciprofloxacin or kanamycin. The offspring larvae were used to infest B. microti-positive mice. Prevalence of B. microti among the nymphs in different treatment groups and its association with endosymbiont density in the larvae were analyzed. The results showed that the prevalence of B. microti in the kanamycin-treated group (63.9%, 95% confidence interval (CI): 52.8–75.0%) was higher than that in the PBS (23.6%, 95% CI: 13.8–33.4%) or ciprofloxacin-treated (25.0%, 95% CI: 15.0–35.0%) groups. This increased prevalence was associated with reduced density of Coxiella-like endosymbiont but was not related to the density of Rickettsia-like endosymbiont. No direct evidence has previously been reported about the impact of Coxiella-like endosymbiont on pathogen susceptibility in ticks. This study reveals that endosymbionts are potentially important defensive symbionts of R. haemaphysaloides which may influence the colonization or susceptibility of B. microti in the tick host.

Effects of antibiotic treatment on the fecundity of Rhipicephalus haemaphysaloides ticks

BACKGROUND

Endosymbiotic bacteria inhabit a variety of arthropods including ticks and may have multiple effects on the host's survival, reproduction or pathogen acquisition and transmission. Rhipicephalus haemaphysaloides is one of the most widely distributed tick species in China. The symbiotic bacteria composition and their impacts to R. haemaphysaloides ticks have not been studied. The present study investigated the composition of microbial community in R. haemaphysaloides ticks and then assessed the effects of endosymbionts on the host's fecundity by antibiotic treatment experiments.

METHODS

The microbial population of female and male R. haemaphysaloides ticks was analyzed using Illumina Miseq sequencing of 16S rRNA gene. Thirty engorged female ticks were then randomly divided into five groups and injected with ampicillin, ciprofloxacin, kanamycin, tetracycline, or phosphate-buffered solution (PBS), respectively. Effects of antibiotic treatments on maternal oviposition, egg hatching and density of endosymbionts were evaluated.

RESULTS

Illumina Miseq sequencing showed that Coxiella and Rickettsia were the predominant bacterial genera inhabiting R. haemaphysaloides ticks. Antibiotic treatment experiments found that kanamycin reduced the density of Coxiella-like endosymbiont (Coxiella-LE hereafter) in eggs, ciprofloxacin reduced the density of Rickettsia-like endosymbiont (Rickettsia-LE), and tetracycline had effect on both endosymbionts, while ampicillin affected neither. Meanwhile hatching rates of eggs were observed to decrease greatly in the kanamycin or tetracycline-treated group but maintained in the ampicillin or ciprofloxacin-treated group. Furthermore, the reduced hatching rates were found to be associated with density of Coxiella-LE in eggs.

CONCLUSIONS

The findings indicate that Coxiella-LE is essential for the reproduction of R. haemaphysaloides ticks, and that kanamycin can be used to study the role of Coxiella-LE on ticks.

[Association between serum Nε-carboxymethyl-lysine level and anterior tibial arterial plaque calcification in patients with diabetic foot post foot amputation]

Objective: To observe the correlation between Nε-carboxymethyl-Lysine (CML), the main component of advanced glycation end products and the calcification of the anterior tibial artery plaque in patients with diabetic foot post foot amputation. Methods: Sixty patients hospitalized for foot amputation operation due to diabetic foot from June 2012 to June 2016 in the Department of Orthopedics, Affiliated Hospital of Jiangsu University were prospectively recruited.The patients were categorized into mild stenosis (0<stenosis<50%, n=20), moderate stenosis (50%≤stenosis<70%, n=20) and severe stenosis (70%≤stenosis≤100%, n=20) based on the color Doppler ultrasound assessed severity of anterior tibial artery stenosis.The baseline clinical data of patients were collected and anterior tibial artery was isolated.Then, HE staining, O-Cresolphthalein Complexone method, enzymic method and ELASA analysis were then performed to detect the evolution of calcification, arterial calcium content, alkaline phosphatase activity and serum CML concentration, respectively. Results: The results from both color Doppler ultrasound scan before amputation and HE staining after amputation showed that echo intensity as well as spotty blue calcium particles of anterior tibial artery plaque increased significantly in proportion to degree of stenosis and destructed elastic plate of the arterial wall was evidenced in patients with severest stenosis.The content of calcium ((2.3±0.9), (3.9±1.3), (6.6±1.7) μmol/mg, respectively, P<0.001), ALP activity ((102.4±39.4), (202.3±73.4), (483.7±117.9) U/mg, respectively, P<0.001) and serum CML level ((28.9±4.4), (37.9±5.3), (57.3±7.1)μg/L, respectively, P<0.001) increased significantly in proportion to stenosis severity.Pearson correlation analysis showed that serum CML level was positively correlated with the content of calcium (r=0.749, P<0.001) and ALP activity (r=0.923, P<0.001), respectively. Conclusions: Serum CML level is positively correlated with the calcification of anterior tibial arterial plaque in patients with diabetic foot and could be used to evaluate the calcification of anterior tibial arterial plaque and stenosis degree of anterior tibial arterial in these patients.

Second-harmonic imaging microscopy for identifying colorectal intraepithelial neoplasia

In this study, second-harmonic imaging microscopy was used to monitor precancerous colorectal lesions at different stages. It was found that the morphology of glands and lamina propria in mucosa changes with the progression of colorectal diseases from normal to low-grade intraepithelial neoplasia to high-grade intraepithelial neoplasia and this microscopy has the ability of direct visualization of these warning symptoms. Furthermore, two morphologic variables were quantified to determine the changes of glands and collagen in lamina propria during the development of colorectal intraepithelial neoplasia. These results suggest that second-harmonic imaging microscopy has the potential in label-freely and effectively distinguishing between normal and precancerous colorectal tissues, and will be helpful for early diagnosis and treatment of colorectal diseases.

Silver-based surface plasmon waveguide for terahertz quantum cascade lasers

Terahertz-frequency quantum cascade lasers (THz QCLs) based on ridge waveguides incorporating silver waveguide layers have been investigated theoretically and experimentally, and compared with traditional gold-based devices. The threshold gain associated with silver-, gold- and copper-based devices, and the effects of titanium adhesion layers and top contact layers, in both surface-plasmon and double-metal waveguide geometries, have been analysed. Our simulations show that silver-based waveguides yield lower losses for THz QCLs across all practical operating temperatures and frequencies. Experimentally, QCLs with silver-based surface-plasmon waveguides were found to exhibit higher operating temperatures and higher output powers compared to those with identical but gold-based waveguides. Specifically, for a three-well resonant phonon active region with a scaled oscillator strength of 0.43 and doping density of 6.83 × 10¹⁵ cm^-3, an increase of 5 K in the maximum operating temperature and 40% increase in the output power were demonstrated. These effects were found to be dependent on the active region design, and greater improvements were observed for QCLs with a larger radiative diagonality. Our results indicate that silver-based waveguide structures could potentially enable THz QCLs to operate at high temperatures.

Electrical and Optical Properties of In₂O₃ Thin Films Deposited on Sapphire Substrate

In2O3 thin films were prepared on c-plane sapphire substrates using laser molecular beam epitaxy technique. The X-ray diffraction (XRD) patterns revealed that the In2O3 thin films were highly oriented along the (111) direction. The intensity of (222) diffraction peaks mainly depend on growth temperature, and the crystallite sizes mainly depend on oxygen pressure. The carrier concentrations exhibit a decrease with increasing growth temperature and oxygen pressure, meantime, the resistivity increase. The red shift of In2O3 thin films respect to that of bulk In2O3 can be explained by defect energy levels formation, the blue shift of In2O3 thin films depends on carrier concentration, can be explained by Burstein-Moss band-filling effect.

[Relationship between large artery elasticity function and coronary heart disease, lower extremity arterial disease in patients with carotid plaque]

OBJECTIVE

To evaluate the relationship between large artery elastic function and coronary heart disease (CHD) or lower extremity arterial disease (LEAD) in patients with carotid plaque.

METHODS

A total of 491 patients with carotid plaque were enrolled into the study with complete data of arterial stiffness detection and blood test [male: 208 and female: 283, and mean age: (61.66±11.60) years]. All the subjects were divided into 2 groups according to CHD or LEAD, namely non-CHD&LEAD group (neither CHD nor LEAD) and CHD/LEAD group (either CHD or LEAD). Accor-ding to the mean age level (age<61.66 years or age>61.66 years), the independent association was analyzed between higher large arterial stiffness (carotid-femoral pulse wave velocity, CF-PWV, CF-PWV>9 m/s) and CHD/LEAD.

RESULTS

In the present research population, the mean level of arterial stiff-ness was high (the mean CF-PWV was 10.71 m/s), and 76.6% of them had arteriosclerosis, and 36.9% CHD/LEAD. The age, male and smoking proportion, systolic blood pressure (SBP), glycosylated hemoglobin (HbA1c), homocysteine (Hcy), creatinine (Cr), CF-PWV, prevalence rate of hypertension and diabetes mellitus, medication on hypertension, diabetes and hyperlipidemia were higher in CHD/LEAD group, and total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) were lower in CHD/LEAD group than in non-CHD&LEAD group (all P<0.05).In multivariate Logistic regression analysis, the results showed that in the patients with age below 61.66 years, large artery stiffness (CF-PWV>9 m/s) was an independent risk factor of CHD/LEAD (OR=3.229, 95%CI 1.156-9.022, P<0.05); In the patients with age above 61.66 years, there was no independent association between large artery stiffness and CHD/LEAD (P>0.05).

CONCLUSION

The large artery elasticity function in the patients with carotid plaque was poor. In the patients with carotid plaque and higher large artery stiffness below 61.66 years, the risk of the prevalence of CHD/LEAD was increased significantly than with normal arterial stiffness. In the patients with carotid plaque below or above 61.66 years, the independent influencing factors on the prevalence of CHD/LEAD were different.

[Clinical efficacy of pegylated interferon in patients co-infected with HIV and HCV who failed standard interferon therapy]

OBJECTIVE

To investigate the efficacy and safety of pegylated interferon-alpha (PEG-INF-α) combined with ribavirin in patients co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) who failed prior standard interferon therapy.

METHODS

A prospective study was performed to analyze HCV RNA load, liver function, and CD4+ count at weeks 0 (baseline), 12, 24, and 48 of treatment and at 24 weeks after drug discontinuation in 20 patients co-infected with HIV and HCV who failed standard interferon therapy and were then treated with PEG-INF-αand ribavirin.

RESULTS

Among the 20 patients, 14 were infected with HCV genotype 1b, 3 with HCV genotype 2a, and 3 failed sequencing. At baseline, the mean CD4(+)count, mean CD8(+)count, and mean CD4(+)/CD8(+)ratio were 406.45 ± 210.83 cells/ml, 1 076.45 ± 716.18 cells /ml, and 0.43 ± 0.17, respectively; the mean HCV RNA load was 6.01 ± 1.13 log10IU/ml; 12 patients (60%) had abnormal liver function. A total of 14 patients (70%) achieved complete early virologic response, 15 (75%) achieved end-of-treatment virologic response, 7 (35%) achieved sustained virologic response (SVR), and 8 (40%) experienced recurrence. The incidence rate of drug-related adverse events during the treatment was 50% (10/20); no serious adverse events occurred, and no patient withdrew from the treatment due to adverse events. At week 48, both CD4(+)and CD8(+)counts of all patients declined significantly compared with the baseline values (P= 0.001 and 0.001), but the CD4(+)/CD8(+)ratio increased significantly (P= 0.032). The SVR group had a significantly lower mean baseline HCV RNA load than the non-SVR group (4.95 ± 1.18 log10IU/ml vs 6.59 ± 0.53 log10IU/ml,t= 3.49,P= 0.009).

CONCLUSION

In the patients co-infected with HIV and HCV who failed standard interferon therapy, PEG-INF-αcombined with ribavirin has good efficacy and safety, and the patients with a low baseline HCV RNA load are more likely to achieve SVR.

[Diagnostic value of quantitative pharmacokinetic parameters and relative quantitative pharmacokinetic parameters in breast lesions with dynamic contrast-enhanced MRI]

Objective: To explore the differential between the value of dynamic contrast-enhanced MRI quantitative pharmacokinetic parameters and relative pharmacokinetic quantitative parameters in breast lesions. Methods: Retrospective analysis of 255 patients(262 breast lesions) who was obtained by clinical palpation , ultrasound or full-field digital mammography , and then all lessions were pathologically confirmed in Zhongda Hospital, Southeast University from May 2012 to May 2016. A 3.0 T MRI scanner was used to obtain the quantitative MR pharmacokinetic parameters: volume transfer constant (K(trans)), exchange rate constant (k(ep))and extravascular extracellular volume fraction (V(e)). And measured the quantitative pharmacokinetic parameters of normal glands tissues which on the same side of the same level of the lesions; and then calculated the value of relative pharmacokinetic parameters: rK(rans)、rk(ep) and rV(e).To explore the diagnostic value of two pharmacokinetic parameters in differential diagnosis of benign and malignant breast lesions using receiver operating curves and model of logistic regression. Results: (1)There were significant differences between benign lesions and malignant lesions in K(trans) and k(ep) (t=15.489, 15.022, respectively, P<0.05), there were no significant differences between benign lesions and malignant lesions in V(e)(t=-2.346, P>0.05). The areas under the ROC curve(AUC)of K(trans), k(ep) and V(e) between malignant and benign lesions were 0.933, 0.948 and 0.387, the sensitivity of K(trans), k(ep) and V(e) were 77.1%, 85.0%, 51.0% , and the specificity of K(trans), k(ep) and V(e) were 96.3%, 93.6%, 60.8% for the differential diagnosis of breast lesions if taken the maximum Youden's index as cut-off. (2)There were significant differences between benign lesions and malignant lesions in rK(trans), rk(ep) and rV(e) (t=14.177, 11.726, 2.477, respectively, P<0.05). The AUC of rK(trans), rk(ep) and rV(e) between malignant and benign lesions were 0.963, 0.903 and 0.575, the sensitivity of rK(trans), rk(ep) and rV(e) were 85.6%, 71.9%, 52.9% , and the specificity of rK(trans), rk(ep) and rV(e) were 94.5%, 92.7%, 60.6% for the differential diagnosis of breast lesions.(3)There was no significant difference in the area under the ROC curve between the predictive probability of quantitative pharmacokinetic parameters and the prediction probability of relative quantitative pharmacokinetic parameters(Z=0.867, P=0.195). Conclusion: There was no significant difference between the quantitative parameter values (K(trans,) k(ep)) and the relative quantitative parameter values (rK(trans,) rk(ep)) in diagnosis of breast lesions, which were important parameters in differential diagnosis of benign and malignant breast lesions.

[The value of lung ultrasound score for therapeutic effect assessment of ventilator-associated pneumonia]

To study the value of lung ultrasound score (LUS) in assessing the clinical outcome of patients with ventilator-associated pneumonia(VAP). A total of 99 VAP patients were enrolled in a prospective study. All patients met the diagnostic criterion of VAP based on the 2013 guidelines and admitted into our ICU from Jun 2013 to Jun 2015. All parameters were recorded on the diagnostic day (day 1) and day 5, including LUS, clinical pulmonary infection score (CPIS), chest X ray (CXR), Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Sequential Organ Failure Assessment(SOFA) score, etc. According to the CPIS, patients were divided into 2 groups(CPIS less than 6 and more or equal to 6). CPIS and LUS were similar on day 1 between two groups (P>0.05). However, on day 5, significant differences of CPIS and LUS were found between groups with CPIS<6 and CPIS≥6 (P=0.019 and P<0.001 respectively). LUS decreased on day 5 in CPIS<6 group and increased in CPIS≥6 group. In CPIS<6 group, there was a positive correlation between LUS and CPIS on day 1(r=0.375, P=0.003) and day 5 (r=0.590, P<0.001). CPIS≥6 groupshowed the same trend on day 1 (r=0.484, P=0.002) and day 5 (r=0.407, P=0.011). LUS can be used to dynamically evaluate the clinical outcome of VAP.