Construction of porous carbon for the highly efficient visible light-driven degradation methyl violet

A series of nanoporous carbons (NPC) Fe-C/N-900 and C/N-900 have been synthesized from one-step carbonization of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin-Fe (Fe-TCPP) and TCPP, respectively and employed as photocatalyst for the degradation of organic dye methyl violet (MV) under UV irradiation. The optimized Fe-C/N-900 (carbonized at 900 oC for 2 h) exhibited an optimal performance in MV degradation. The photodegradation capacity of Fe-C/N-900 has been observed to be higher than that of C/N-900. The photodegradation ability of Fe-C/N-900 as a function of initial MV concentration, catalysis dosage, and pH has been also investigated. The Fe-C/N-900 material showed no apparent loss in MV degradation after four cycles. These features reveal that Fe-C/N-900 may be a promising degradant for dyes removal from water.                     KEY WORDS: Photocatalysis, Nanoporous carbons, Methyl violet, carbonization   Bull. Chem. Soc. Ethiop. 2020, 34(2), 277-284 DOI: https://dx.doi.org/10.4314/bcse.v34i2.6

[Assessment of schistosomiasis transmission risk in Nanjian County of Yunnan Province in 2019]

OBJECTIVE

To assess the schistosomiasis transmission risk in Nanjing County, so as to provide the scientific evidence for the development of the schistosomiasis control strategy and consolidation of the control achievements.

METHODS

On May 2019, the Deqiu Village in Deqiu Town and Baiyun Village in Nanjing Town of Yunnan Province, where schistosomiasis were historically relatively highly endemic, were selected to assess the risk of transmission of schistosomiasis by means of a retrospective review of the data pertaining to the historical endemic situation and schistosomiasis control, combined with a cross-sectional survey of snail and wild feces distribution.

RESULTS

During the period between 2017 and 2018, the mean sero-prevalence rates of Schistosoma japonicum infections were 6.76% (202/2 990) and 2.86% (142/4 971) in humans and 0 (0/1 160) and 10.65% (31/291) in bovines in Deqiu and Baiyun villages of Nanjian County, respectively; however, no egg-positives were identified; in addition, there were 21.06 hm² snail habitats found, but no S. japonicum infections were detected in snails. In 2019, there was 6.17 hm² snail habitats detected, with 2.17% (245/11 298) occurrence of frames with snails and a 0.06 snails/0.1 m² density of living snails; however, no positives for nucleic acid detection were seen in snails; among the 136 wild fecal samples captures from 23 settings, no S. japonicum infections were identified.

CONCLUSIONS

The risk of schistosomiasis transmission remains at a low level in Nanjian County; however, the factors affecting the transmission of schistosomiasis have not been completed eliminated. The integrated schistosomiasis control strategy with an emphasis on the control of the source of S. japonicum infections requires to be reinforced to consolidate the control achievements.

Nodal mitigates cerebral ischemia-reperfusion injury via inhibiting oxidative stress and inflammation

OBJECTIVE

Nodal is a member of the transforming growth factor β (TGF-β) family, which induces the activation of the cytoplasmic Smad2 and Smad3, both of which play a neuroprotective role against cerebral ischemia-reperfusion (I/R) injury. However, the  role of Nodal in cerebral I/R is unclear. Thus, the aim of the present study was to shed light on the function of Nodal in cerebral I/R injury.

MATERIALS AND METHODS

Cerebral I/R injury was induced in the Sprague Dawley (SD) rats by middle cerebral artery occlusion (MCAO) and reperfusion and in murine hippocampal neuronal cells (HT22) by oxygen-glucose deprivation/reperfusion (OGD/R) stimulation. The lentivirus vectors (Nodal overexpressing lentivirus vector [OE-Nodal] and the short hair RNA of Nodal [sh-Nodal]) were used to upregulate and downregulate Nodal in SD rats or cells.

RESULTS

Nodal expression increased in the cerebral I/R models and reached a peak after 12 h of reperfusion. OE-Nodal administration to the cerebral I/R rats significantly reduced the cerebral infarction volume and inhibited the brain cell apoptosis. It also increased the level of superoxide dismutase (SOD), an antioxidant enzyme, and decreased the levels of the lipid peroxides (malondialdehyde [MDA] and lactate dehydrogenase [LDH]), in addition to those of the proinflammatory factors. Consistently, the upregulation of Nodal in HT22 by OGD/R significantly increased the SOD level and decreased the levels of MDA, LDH, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α).

CONCLUSIONS

This study revealed that Nodal exerted a protective role during cerebral I/R by inhibiting excessive oxidative stress and inflammation.

Downregulated LINC00460 inhibits cell proliferation and promotes cell apoptosis in prostate cancer

OBJECTIVE

LINC00460 has been confirmed to contribute to cancer development. However, the role and function of LINC00460 in prostate cancer is not identified. The purpose of this study was to evaluate the expression and effect of LINC00460 on prostate cancer cell malignant behaviors.

PATIENTS AND METHODS

The expression of LINC00460 in cancer tissues and cell lines were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay. The LINC00460 expression was downregulated by siRNA. The cell counting kit-8 (CCK-8) assay was used to detect cell proliferation. The cell migration and invasion were detected by migration and Matrigel invasion assays. The Western blot assay was used to detect the altered expression levels of Ki67, Cyclin D1, PI3K, p-AKT, T-AKT, Bcl2, and Bax.

RESULTS

LINC00460 was increased in human prostate cancer tissues and cell lines. LINC00460 high expression was related to Tumor Size (T1-T2/T3-T4; p=0.004), and high Gleason Score (≤8/>8, p=0.000). Downregulation of LINC00460 by siRNA could inhibit cancer cell proliferation and decreased Ki67 and Cyclin D1 expression. Meanwhile, downregulation of LINC00460 promoted apoptosis of cell lines and was related to PI3K/AKT pathway.

CONCLUSIONS

LINC00460 could regulate cell proliferation and cell apoptosis, which might be a novel marker in prostate cancer.

[Analysis of treatment response and prognostic factors of T-LBL patients treated with pediatric-like ALL therapy following HSCT]

目的

探讨经急性淋巴细胞白血病（ALL）儿童方案治疗达到完全缓解（CR）和部分缓解（PR）的T淋巴母细胞淋巴瘤（T-LBL）患者应用造血干细胞移植巩固治疗的疗效及预后因素。

方法

收集2013年1月至2017年1月于唐都医院血液病中心接受治疗的T-LBL患者的临床资料，将达到CR或PR的患者纳入研究，进行回顾性分析。

结果

①48例患者接受了ALL儿童方案治疗，经2个疗程的诱导化疗后39例达CR，9例达PR。其中接受自体造血干细胞移植（auto-HSCT）者14例，接受异基因造血干细胞移植（allo-HSCT）者7例，21例患者移植后造血功能均顺利重建。②中位随访时间31（9～16）个月。3年总生存（OS）率为61.0%（95% CI 53.7%～68.3%），3年无进展生存（PFS）率为54.8%（95% CI 47.1%～62.2%）。③移植组和未移植组3年OS率分别为84.7%和42.8%（P＝0.006），两组3年PFS率分别为75.4%和38.9%（P＝0.004）。④auto-HSCT组与allo-HSCT组患者的OS率、PFS率差异均无统计学意义（P值分别为0.320、0.597）。⑤骨髓侵犯、未接受造血干细胞移植是影响患者长期预后的独立危险因素［ HR＝5.804（95% CI 1.140～29.549），P＝0.034；HR＝5.871（95% CI 1.711～20.140），P＝0.005］。

结论

ALL儿童方案化疗序贯造血干细胞移植治疗T-LBL疗效确切，安全性好。auto-HSCT与allo-HSCT患者的OS率及PFS率差异均无统计学意义。骨髓侵犯、未接受造血干细胞移植是影响T-LBL患者长期预后的独立危险因素。

[Characteristic and clinical significance of microRNA expression between 144 Uygur and Han women with endometrial carcinoma]

OBJECTIVE

To compare the expression patterns of microRNA (miRNA) between 144 Uygur and Han women with endometrial carcinoma and to investigate their clinical significance.

METHODS

Taqman miRNA low-density array was used to compare miRNA profiles between Uygur and Han women with non-endometrioid endometrial carcinoma (NEEC). Five miRNAs were further analyzed in the 144 endometrial cancers including 62 Uygur and 82 Han samples via real-time PCR to determine their expression patterns.

RESULTS

MiRNA expression profiles revealed that many miRNAs overexpressed or downregula-ted in one ethnic group, but did not express or changed slightly in the other ethnic group. Further detection in the 144 endometrial cancers showed that miR-141, miR-200a, and miR-205 overexpressed in both ethnic groups. In Uygur endometrioid endometrial carcinoma (EEC), tumors with miR-141/200a overexpression tended to be more aggressive in behavior, whereas in the Han group, EEC with miR-200a overexpression was relative mild. However, the NEEC with miR-200a overexpression also had aggressive clinicopathologic features in the Han women. MiR-145 and miR-143 expressed differentially between Uygur and Han groups, they overexpressed in the former and decreased in the latter (P<0.05). In the Uygur women miR-145/143 increased significantly in NEEC and there was a trend that NEEC exhibiting favorable clinicopathologic factors had higher miR-145 expression, and was statistically significant in tumors with myometrial invasion less than 1/2 thickness (P=0.042). By contrary, miR-145/143 decreased in Han group and EEC with worse clinicopathologic variables had lower expression although without statistical significance. NEEC in Han group had no such tendency.

CONCLUSION

Uygur and Han women might have different miRNA expression profiles. MiR-141/200a/205 overexpressed in endometrial carcinomas and miR-141/200a might behave differently between these two ethnic groups as well as in EEC and in NEEC. Although miR-145/143 showed inverse expression patterns between Uygur and Han women with endometrial cancer, they all exerted tumor suppression effect on endometrial cancer.

Inhibition of autophagy by 3-MA promotes hypoxia-induced apoptosis in human colorectal cancer cells

OBJECTIVE

Cell autophagy reduces the sensitivity of cancer cells to therapeutic reagents in various types of human cancer. Therefore, the aim of our study was to use human colorectal cancer HCT116 cells to explore whether inhibition of autophagy by 3-Methyladenine (3-MA, an autophagy inhibitor) is able to enhance hypoxia-induced apoptosis in vitro.

MATERIALS AND METHODS

HCT116 cells were treated with 3-MA, hypoxia, or 3-MA plus hypoxia, and the autophagy, apoptosis and proliferation of the HCT116 cells were investigated. Western blot analysis was used to detect autophagy specificity protein microtubule-associated protein light chain 3 (LC3) expression. Effects on apoptosis were evaluated by using flow cytometry (JC-1 staining to measure mitochondrial membrane potential) and annexin V-propidium iodide (PI) staining.

RESULTS

The results showed that the treatment of HCT116 cells in vitro with hypoxia alone increased autophagy as well as apoptosis, whereas combination treatment with 3-MA and hypoxia markedly inhibited hypoxia-induced autophagy, but increased hypoxia-induced cell apoptosis.

CONCLUSIONS

Autophagy might play a role as a self-defense mechanism in hypoxia-treated colon cancer cells, and its inhibition could be a promising strategy for the adjuvant chemotherapy of colon cancer.

Plasma exosomal miR-125a-5p and miR-141-5p as non-invasive biomarkers for prostate cancer

Predictive biomarkers for early diagnosis of prostate cancer are important for its treatment. The functional microRNAs in the exosomes of plasma and serum samples are of interest as stable and non-invasive biomarkers for recurrence in cancer patients. The present study aimed to clarify the value of plasma exosomal miRNA-125a-5p and miR-141-5p as biomarkers for the diagnosis of prostate cancer. The study included 19 healthy individuals and 31 prostate cancer patients. In comparison to the levels in healthy controls, exosomal miR-141-5p levels showed a slight increase in prostate cancer patients (p=0.085), and miR-125a-5p levels that showed a significant decrease in patients with prostate cancer than in healthy controls (p=0.032). As a derived parameter, the miR-125a-5p/miR-141-5p ratio was significantly higher in patients with prostate cancer than in healthy controls (p<0.001). We found that exosomal miR-141-5p in plasma showed a promise in distinguishing prostate cancer patients with the AUC of 0.652, and for miR-125a-5p, the AUC was 0.691. For the miR-125a-5p/miR-141-5p ratio, the AUC value was 0.793. We found that miR-125a-5p has a weak positive correlation with PSA (correlation coefficient = 0.3413). Moreover, miR-141-5p has been found to hold a negatively no-significant correlation with PSA, with the correlation coefficient is -0.1102. We speculate that, as diagnostic markers for prostate cancer, miR-125-5p and miR-141-5p might be independent of the PSA. In summary, the results of this study suggest that high plasma exosomal expression of miR-141-3p and low expression of miR-125a-5p in plasma exosomes from prostate cancer patients might be useful markers of specific tumor traits associated with prostate cancer. Moreover, the miR-125a-5p/miR-141-5p ratio seems to perform better than either of the single values alone.

[Molecular identification of Tricula spp. and the parasitized trematode cercariae in schistosomiasis-endemic areas of Yunnan Province]

OBJECTIVE

To characterize a species of the genus Tricula and parasitized trematodes in schistosomiasis-endemic areas of Yunnan Province using a molecular analysis, so as to understand their taxonomic positions.

METHODS

Tricula spp. and Oncomelania snails were collected from Xiangyun County, Yunnan Province, and cercaria parasitizing snails were observed using crushing followed by microscopy. Cercaria parasitizing Tricula snails at various morphologies were sampled using a shedding method. Genomic DNA was extracted from snail soft tissues and cercariae, and the 16S rRNA, COI, 28S rDNA genes in snails and the ND1 and 28S rDNA genes in cercariae were amplified using a PCR assay and sequenced. The species of Tricula snails and their parasitized trematodes was characterized using sequence alignment and phylogenetic analysis.

RESULTS

Among 382 Tricula snails detected, there were three types of trematode cercariae found, including the non-forked (20.94%, 80/382), double-forked (3.40%, 13/382) and swallow shapes (7.07%, 27/382). Sequence and phylogenetic analyses showed that the 16S rRNA, COI and 28S rDNA gene sequences of this species of Tricula had high homology to those in Delavaya dianchiensis, and were clustered in a branch. Sequencing analysis of the ND1 and 28S rDNA genes revealed that the non-forked cercariae belonged to the family Pleu- rogenidae, the swallow-shaped cercariae belonged to the family Opecoelidae, and the double-forked cercariae belonged to another species of the genus Schistosoma that was different from S. sinensium and S. ovuncatum.

CONCLUSIONS

The species and taxonomy of Triculla spp. and their parasitized trematodes are preliminarily determined in schistosomiasis-endemic areas of Yunnan Province; however, further studies are required to investigate the more definite taxonomy and pathogenicity.

[Recommendations of diagnosis and treatment of primary Sjögren's syndrome in China]

Sjögren's syndrome is a chronic systemic autoimmune disease characterized by lymphocyte proliferation and progressive exocrine gland damage. In China, standardized diagnosis and treatment for Sjögren's syndrome lags behind other common rheumatic diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Based on the evidence and guidelines from China and other countries, Chinese Sjögren's Syndrome Collaborative Research Group together with stomatologist and ophthalmologist developed Standardization of diagnosis and treatment of primary Sjögren's syndrome. The purposes are: (1) to standardize the detection and interpretation of key indicators for the diagnosis of Sjögren's syndrome, including serum anti SSA antibody and labial gland pathology; (2) to suggest using widely accepted disease activity index in evaluation of the disease; (3) to standardize rational management for Sjögren's syndrome patients with topical and systemic diseases.

Bandgap tuning of two-dimensional materials by sphere diameter engineering

Developing a precise and reproducible bandgap tuning method that enables tailored design of materials is of crucial importance for optoelectronic devices. Towards this end, we report a sphere diameter engineering (SDE) technique to manipulate the bandgap of two-dimensional (2D) materials. A one-to-one correspondence with an ideal linear working curve is established between the bandgap of MoS₂ and the sphere diameter in a continuous range as large as 360 meV. Fully uniform bandgap tuning of all the as-grown MoS₂ crystals is realized due to the isotropic characteristic of the sphere. More intriguingly, both a decrease and an increase of the bandgap can be achieved by constructing a positive or negative curvature. By fusing individual spheres in the melted state, post-synthesis bandgap adjustment of the supported 2D materials can be realized. This SDE technique, showing good precision, uniformity and reproducibility with high efficiency, may further accelerate the potential applications of 2D materials.

GPR39 Overexpression in OSCC Promotes YAP-Sustained Malignant Progression

The clinical outcome of oral squamous cell carcinoma (OSCC) has not improved in recent years, mainly due to the limited effective targeted therapy that has been applied. Recently, a transcriptional coactivator, YAP, has been shown to have a key regulatory role in malignant progression in multiple cancers, including OSCC. But pharmacologically targeting YAP or the Hippo pathway, which is the main signaling pathway regulating YAP, has been proven to be challenging. Therefore, uncovering YAP upstream regulators in cancer would identify novel therapeutic targets for treatment of YAP-sustained cancers. Here, we showed that YAP was overactivated in OSCC and that high YAP activity in patients with OSCC was associated with malignant progression and poor survival. We uncovered that GPR39 (a G protein-coupled receptor) was overexpressed in OSCC, that the expression level of GPR39 was correlated with the activity level of YAP, and that the high GPR39 expression was associated with malignant progression and poor survival in patients with OSCC. Moreover, we found that GPR39 regulated YAP through a Gαq/11-RhoA-dependent signaling pathway. Importantly, inhibition of GPR39 resulted in YAP-sustained OSCC growth inhibition. Our findings suggest that GPR39 is a potential therapeutic target for OSCC treatment with itself as a biomarker.

Correlation-driven eightfold magnetic anisotropy in a two-dimensional oxide monolayer

Engineering magnetic anisotropy in two-dimensional systems has enormous scientific and technological implications. The uniaxial anisotropy universally exhibited by two-dimensional magnets has only two stable spin directions, demanding 180° spin switching between states. We demonstrate a previously unobserved eightfold anisotropy in magnetic SrRuO3 monolayers by inducing a spin reorientation in (SrRuO3)1/(SrTiO3) N superlattices, in which the magnetic easy axis of Ru spins is transformed from uniaxial 〈001〉 direction (N < 3) to eightfold 〈111〉 directions (N ≥ 3). This eightfold anisotropy enables 71° and 109° spin switching in SrRuO3 monolayers, analogous to 71° and 109° polarization switching in ferroelectric BiFeO3. First-principle calculations reveal that increasing the SrTiO3 layer thickness induces an emergent correlation-driven orbital ordering, tuning spin-orbit interactions and reorienting the SrRuO3 monolayer easy axis. Our work demonstrates that correlation effects can be exploited to substantially change spin-orbit interactions, stabilizing unprecedented properties in two-dimensional magnets and opening rich opportunities for low-power, multistate device applications.

[Survival analysis of laboratory - bred smooth - shelled Oncomelania snails in Yunnan Province]

OBJECTIVE

To investigate the survival period of Yunnan Province-derived smooth-shelled Oncomelania snails bred in laboratory.

METHODS

Oncomelania snails were sampled from Heqing and Yongsheng counties where schistosomiasis is endemic, and uninfected adult snails were collected and bred in laboratory. The survival period of snails sampled from these two counties was compared.

RESULTS

The 1-, 2-, 3- and 4-year survival rates of laboratory-bred smooth-shelled snails sampled from Yunnan Province were 72.36%, 29.11%, 13.08% and 0.21%, respectively, and were 74.66%, 38.91%, 19.46% and 0.45% for snails derived from Heqing County, and 70.36%, 20.55%, 7.51% and 0 for snails sampled from Yongsheng County, respectively. The mean and median survival period of Yunnan Province-derived adult snails was 20.90 and 20.67 months, and there were significant differences between the snails sampled from Heqing and Yongsheng counties in terms of the mean (22.94 vs. 19.13 months, P < 0.05) and median survival period (21.63 vs. 19.81 months, P < 0.05).

CONCLUSIONS

The mean survival period of Yunnan Province-derived smooth-shelled adult snails is approximately 20 months in laboratory, and the survival varies in geographical areas.

Growth of High-Quality Superconducting FeSe0.5Te0.5 Films on Pb(Mg1/3Nb2/3)0.7Ti0.3O3 and Electric-Field Modulation of Superconductivity

Heterostructures composed of superconductor and ferroelectrics (SC/FE) are very important for manipulating the superconducting property and applications. However, growth of high-quality superconducting iron chalcogenide films is challenging because of their volatility and FE substrate with rough surface and large lattice mismatch. Here, we report a two-step growth approach to get high-quality FeSe_0.5Te_0.5 (FST) films on FE Pb(Mg_1/3Nb_2/3)_0.7Ti_0.3O₃ with large lattice mismatch, which show superconductivity at only around 10 nm. Through a systematic study of structural and electric transport properties of samples with different thicknesses, a mechanism to grow high-quality FST is discovered. Moreover, electric-field-induced remarkable change of T_c (superconducting transition temperature) is demonstrated in a 20 nm FST film. This work paves the way to grow high-quality films which contain volatile element and have large lattice mismatch with the substrate. It is also helpful for manipulating the superconducting property in SC/FE heterostructures.

[Effect of different support angles on the fitness of removable partial denture framework fabricated using selective laser melting technique]

Objective: To evaluate the fitness of bilateral free-end dentition defect removable partial denture framework fabricated by selective laser melting (SLM) technique with different support angles. Methods: After the control group has been set to eliminate the system error, and according to the standard model of bilateral mandibular posterior teeth loss, eighteen titanium alloy removable partial denture frameworks fabricated by SLM technology were divided into 3 groups with support angles of 0° (horizontal group), 45°(45° group) and 90° (vertical group). Plaster cast with duplicated structure of tissue surface of the removable partial denture (RPD) framework was obtained. A three-dimensional scanner was used to scan original and duplicated plaster casts. The gaps between framework and the model in different parts were analyzed using Geomagic Qualify software to evaluate the fitness of the framework with visual method. Results: The framework fits on the plaster model completely, and its tissue surface fitted on the plaster model well. The deviation between frameworks and plaster casts was calculated as follow: the total deviations of the horizontal, 45°, and vertical group were (0.146±0.017), (0.182±0.015) and (0.185±0.022) mm respectively. The mean deviation of the horizontal group was significantly less than those of the 45° group and the vertical group (P<0.05). Moreover, there was no significant difference in the total deviation between the 45° group and the vertical group. The total deviation of occlusal rest of the horizontal group was significantly less than that of the 45° group (P<0.05). However, no significant difference was detected in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group (P>0.05). There was no significant difference in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group. The deviation of clasp of the horizontal group was significantly smaller than those of the 45° group and the vertical group (P<0.05). Whereas, there was no significant difference in the deviation of clasp between the 45° group and the 90° group (P>0.05). No significant difference was found in the deviation of lingual bar among the three groups (P>0.05). Conclusions: Among the three kinds of bilateral free-end dentition defect RPD framework fabricated by SLM in different support angles, horizontal printing was proved to reach the minimal deviation, even though the fitness of all three kinds of frameworks can fullfil clinical requirements according to previous studies.

Risk assessment of mycotoxins in stored maize: case study of Shandong, China

Risk characterisation of dietary exposure of aflatoxins (AFs), fumonisins (FBs), deoxynivalenol (DON), zearalenone (ZEA) in maize from Shandong Province was conducted in this study. A total of 520 maize samples were collected after harvesting in 2014 and 2015 from 26 selected villages in Shandong Province, China. A deterministic approach was used in the current study. The dietary intake data of maize was obtained from ‘Shandong Statistical Yearbook 2018’. The risk characterisation of FBs, DON, and ZEA was evaluated in 4 population groups (2 to 6-year-old children, standard adults, city adults and village adults) based on probable intake. 2 to 6-year-old children and adults were exposed to FBs (0.42 and 0.20 μg/kg body weight (bw)/day), DON (0.04 and 0.019 μg/kg bw/day), and ZEA (0.0024 and 0.0011 μg/kg bw/day) through mean maize consumption in diets, which was lower than the provisional maximum tolerable daily intake of each mycotoxin established by JECFA. Risk assessments showed a low risk for liver cancer due to consumption of aflatoxin B1 (0.027-0.21 cases per 100,000 persons per year) contaminated maize compared with China’s current liver cancer incidence of 24.6 cases per 100,000 persons per year.

Maternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin suppresses male reproductive functions in their adulthood

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a ubiquitous environmental contaminant in the environment. The developmental period is more sensitive to TCDD and there is a possibility that maternal exposure to TCDD may affect in adulthood. Adult female Wistar rats were exposed to 0.5, 1.0, and 2.0 µg/kg TCDD during the critical stage of organogenesis, that is, on GD15. The results revealed a significant decrease in indices of reproductive organ weight in adult male rats exposed to prenatal TCDD, and dose-dependent reduction in epididymal sperm reserves, percent motile, and viable sperm with an increase in percent morphological abnormal sperm. Polymerase chain reaction analysis revealed downregulated expression levels of steroidogenic markers such as steroidogenic acute regulatory, cholesterol side-chain cleavage, and 3β- and 17β-hydroxysteroid dehydrogenase (HSDs) in experimental rats. Immunofluorescence sections portrayed reduced distribution of 3β- and 17β-HSD proteins in testes of experimental rats. Furthermore, spermatogenic markers (acid phosphatase, alkaline phosphatase, lactate dehydrogenase, and sorbitol dehydrogenase) were significantly altered in the testes. Serum levels of testosterone, follicle stimulating hormones, and luteinizing hormone were significantly decreased. Testicular levels of hydrogen peroxide and lipid peroxidation were significantly elevated with a decline in superoxide dismutase, catalase, glutathione peroxidase activities, and total thiol levels. Moreover, histological and morphometric examination of testicular cross-sections depicted degenerative changes. Male fertility assessment in adult rats revealed a significant decrease in mating index, fertility index, and mean number of pre- and postimplantations with an increase in pre- and postimplantation losses in rats cohabited with in utero TCDD-exposed adult males. In conclusion, the findings of this study provided clear evidence that maternal exposure to TCDD during the critical stage of development results in suppressed reproductive health in adulthood.

Tailoring spontaneous infrared emission of HgTe quantum dots with laser-printed plasmonic arrays

Chemically synthesized near-infrared to mid-infrared (IR) colloidal quantum dots (QDs) offer a promising platform for the realization of devices including emitters, detectors, security, and sensor systems. However, at longer wavelengths, the quantum yield of such QDs decreases as the radiative emission rate drops following Fermi's golden rule, while non-radiative recombination channels compete with light emission. Control over the radiative and non-radiative channels of the IR-emitting QDs is crucially important to improve the performance of IR-range devices. Here, we demonstrate strong enhancement of the spontaneous emission rate of near- to mid-IR HgTe QDs coupled to periodically arranged plasmonic nanoantennas, in the form of nanobumps, produced on the surface of glass-supported Au films via ablation-free direct femtosecond laser printing. The enhancement is achieved by simultaneous radiative coupling of the emission that spectrally matches the first-order lattice resonance of the arrays, as well as more efficient photoluminescence excitation provided by coupling of the pump radiation to the local surface plasmon resonances of the isolated nanoantennas. Moreover, coupling of the HgTe QDs to the lattice plasmons reduces the influence of non-radiative decay losses mediated by the formation of polarons formed between QD surface-trapped carriers and the IR absorption bands of dodecanethiol used as a ligand on the QDs, allowing us to improve the shape of the emission spectrum through a reduction in the spectral dip related to this ligand coupling. Considering the ease of the chemical synthesis and processing of the HgTe QDs combined with the scalability of the direct laser fabrication of nanoantennas with tailored plasmonic responses, our results provide an important step towards the design of IR-range devices for various applications.

Reversible manipulation of the magnetic state in SrRuO3 through electric-field controlled proton evolution

Ionic substitution forms an essential pathway to manipulate the structural phase, carrier density and crystalline symmetry of materials via ion-electron-lattice coupling, leading to a rich spectrum of electronic states in strongly correlated systems. Using the ferromagnetic metal SrRuO3 as a model system, we demonstrate an efficient and reversible control of both structural and electronic phase transformations through the electric-field controlled proton evolution with ionic liquid gating. The insertion of protons results in a large structural expansion and increased carrier density, leading to an exotic ferromagnetic to paramagnetic phase transition. Importantly, we reveal a novel protonated compound of HSrRuO3 with paramagnetic metallic as ground state. We observe a topological Hall effect at the boundary of the phase transition due to the proton concentration gradient across the film-depth. We envision that electric-field controlled protonation opens up a pathway to explore novel electronic states and material functionalities in protonated material systems.