Calcium Activation of the Androgen Receptor in Prostate Cells.

Background: Although prostate cancer patients initially respond to androgen deprivation therapy, most patients progress to a resistant phenotype. Castration resistance is due, in part, to intratumoral and/or adrenal synthesis of androgens, overexpression or mutation of the androgen receptor (AR), stabilization of AR by chaperones, and ligand-independent activation of AR. Increasing evidence also links disruption of calcium homeostasis to progression of prostate cancer. Our previous study shows that heavy metal cadmium activates the AR through a ligand-independent mechanism. Cadmium mimics calcium in biological systems due to their similar ionic charge and radius. This study determines whether calcium activates AR and whether first- and second-generation antiandrogens block the ability of calcium to activate the receptor. Methods: The expression of androgen-responsive genes and calcium channels was measured in prostate cells using a quantitative real-time polymerase chain reaction assay. Cell growth was measured. Results: To ask whether calcium activates AR, prostate cells were treated with calcium in the absence and presence of the first-generation antiandrogens hydroxyflutamide and bicalutamide and the second-generation antiandrogen enzalutamide, and the expression of androgen-responsive genes and cell growth was measured. In the normal PWR-1E cells and HEK293T cells transiently expressing AR, treatment with calcium increased the expression of androgen-responsive genes by approximately 3-fold. The increase was blocked by enzalutamide but was not consistently blocked by the first-generation antiandrogens. In LNCaP cells which contain a mutant AR, treatment with calcium also increased the expression of androgen-responsive genes by approximately 3-fold, and the increase was more effectively blocked by enzalutamide than by hydroxyflutamide or bicalutamide. Treatment with calcium also increased cell growth that was blocked by enzalutamide. To ask whether dysregulation of calcium channels is associated with castration resistance, calcium channels were measured in the normal PWR-1E prostate cells, the hormone-responsive LNCaP cells, and the castration-resistant VCaP and 22RV1 cells. Compared to normal prostate cells, the hormone-responsive and hormone-resistant cells overexpressed several calcium channels. Conclusions: The results of this study show that calcium activates AR and increases cell growth and that calcium channels are overexpressed in hormone-responsive and hormone-resistant prostate cancer cells. Taken together, the results suggest a novel role of calcium in the castration-resistant phenotype.

Clinical efficacy and safety of tigecycline based on therapeutic drug monitoring for carbapenem-resistant Gram-negative bacterium pneumonia in intensive care units.

BACKGROUND: We investigated the associations between the different doses of tigecycline, its efficacy and safety, and the role of tigecycline therapeutic drug monitoring for patients in the intensive care unit. METHODS: This study was a single-center cohort including patients infected with multidrug-resistant Acinetobacter baumannii (MDR-AB) and multidrug-resistant Klebsiella pneumoniae (MDR-KP) causing pulmonary infections. The steady-state plasma concentration after tigecycline administration was determined by High-Performance Liquid Chromatography (HPLC) in patients admitted to the ICU between October 2020 and December 2021. Multivariate analyses of tigecycline's clinical efficacy and safety were performed to control confounding factors. RESULTS: For this study, we included 45 patients and 45 blood samples to determine steady-state trough concentrations of tigecycline. All patients were divided into the High Dose (HD) and Standard Dose (SD) groups. The median trough concentration of tigecycline was 0.56 µg/mL in the HD group, which was higher than in the SD group (0,21 µg/mL), p = 0.000. There was no significant difference between the two groups of patients in terms of bacterial eradication rate, mortality rate, and clinical efficacy. Multiple regression analysis showed that the ICU days were correlated with mortality OR 1.030(1.005-1.056), p = 0.017. APACHE II was significantly associated with clinical efficacy OR 0.870(0.755-1.002), p = 0.045. The level of fibrinogen decline in the HD group was significantly higher than in the SD group (-3.05 ± 1.67 vs -1.75 ± 1.90), p = 0.038. We identified that age and tigecycline treatment duration influenced fibrinogen decline. CONCLUSIONS: Tigecycline plasma concentrations are significantly increased when using a high dose. However, the plasma concentration of tigecycline is not correlated with clinical efficacy and adverse reactions. Fibrinogen decline appears to be related to the patient's age and days of tigecycline. Large sample data are still needed to confirm the clinical guidance significance of tigecycline TDM.

Stabilization of Cyclic C4 by Four Donor Ligands: A Theoretical Study of (L)4C4 (L = Carbene).

Quantum chemical studies using density functional theory were carried out for the (L)4C4 complexes with L = cAAC, DAC, NHC, SNHC, MIC1, and MIC2. The results show that the title complexes are highly stable with respect to dissociation, (L)4C4 → C4 + 4L. However, their stability with respect to (L)4C4 → 2(L)2C2 is crucial for the assessment of their experimental viability. The (L)4C4 complexes with L = cAAC and DAC dissociate exergonically at room temperature into two (L)2C2 units. In contrast, the other (L)4C4 complexes with L = NHC, SNHC, MIC1, and MIC2 are thermochemically stable with respect to dissociation, (L)4C4 → 2(L)2C2. The computed adiabatic ionization potentials of (L)4C4 complexes with L = NHC, MIC1, and MIC2 are lower than those for the cesium atom. Particularly, (MIC1)4C4 and (MIC2)4C4 will very easily lose electrons to form cationic complexes. The SNHC ligand is the best for the experimental realization of (L)4C4 complexes, followed by NHC. The bonding analysis using charge and energy decomposition methods suggests that the (L)3C4-CL bond can be best described as a typical electron-sharing double bond with a strong σ-bond and a weaker π-bond. Therefore, the core bonding pictures in the title complexes resemble a [4]radialene. Larger substituents at the carbene ligands enhance the stability of the complexes (L)4C4 against dissociation.

Mimicking the C2 molecule: M2B2 and M3B2+ clusters (M = Li, Na) and the reactivity of the N-heterocyclic carbene bound Li2B2 complex.

C2 has attracted considerable attention from the scientific community for its debatable bonding situation. Herein, we show that the global minima of M2B2 and M3B2+ (M = Li, Na) possess similar covalent bonding patterns to C2. Because of strong charge transfer from M2/M3 to B2 dimer, they can be better described as [M2]2+[B2]2- and [M3]3+[B2]2- salt complexes with the B22- core surrounded perpendicularly by two and three M+ atoms, respectively. The energy decomposition analyses in combination with the natural orbital for chemical valence theory give four bonding components in C2, M2B2, and M3B2+ clusters. However, the fourth component does not arise from a bonding interaction but from polarization/hybridization. Considering the effect of Pauli repulsion in σ-space, the attractive covalent interaction in these molecules mainly comes from the two π-bonds. We further presented stable N-heterocyclic carbene (NHC) and triphenylphosphine (PPh3) ligands bound Li2B2(NHC)2 and Li2B2(PPh3)2 complexes. A comparative study of reactivity towards L = CO2, CO, and N2 between Li2B2(NHC)2 and B2(NHC)2 is also performed. L-Li2B2(NHC)2 is highly stable against L dissociation at room temperature for L = CO2 and CO, and the stability is markedly higher than that in L-B2(NHC)2. The larger B2→L π-backdonation in L-Li2B2(NHC)2 also makes L more activated than in L-B2(NHC)2.

Planar pentacoordinate s-block metals.

The presence of a delocalized π-bond is often considered an essential criterion for achieving planar hypercoordination. Herein, we show that σ-delocalization could be sufficient to make the planar configuration the most stable isomer in a series of planar pentacoordinate s-block metals. High-level ab initio computations reveal that the global minimum of a series of interalkali and interalkali-alkaline earth clusters (LiNa5, Li5Mg+, Na5Mg+, K5Ca+, CaRb5+, Rb5Sr+, and SrCs5+) adopts a singlet D5h structure with a planar pentacoordinate lithium or alkaline earth metal (AE = Mg, Ca, Sr). These clusters are unusual combinations to stabilize a planar pentacoordinate atom, as all their constituents are electropositive. Despite the absence of π-electrons, Hückel's rule is fulfilled by the six σ-electrons. Furthermore, the systems exhibit a diatropic ring current in response to an external magnetic field and a strong magnetic shielding, so they might be classified as σ-aromatic. Therefore, multicenter σ-bonds and the resulting σ-delocalization stabilize these clusters, even though they lack π-aromaticity.

Clusters and bulky Lewis acid protected complexes with planar hexacoordinate beryllium and magnesium.

Planar hexacoordination (ph) is only rarely reported in the literature. So far, only a few neutral and cationic molecules possessing phE (E = C, Si, B, Al, Ga) in the most stable isomer are predicted theoretically. Present electronic structure calculations report hitherto unknown anionic planar hexcoordinate beryllium and magnesium, phBe/Mg, as the most stable isomer. Global minimum searches show that the lowest energy structure of BeC6M3- (M = Al, Ga) and MgC6M3- (M = Ga, In, Tl) is the D3h symmetric phBe/Mg clusters, where beryllium/magnesium is covalently bonded with six carbon centers and M is located in a bridging position between two carbon centers. These global minimum phBe/Mg clusters are highly kinetically stable against isomerization, facilitating the experimental confirmation by photoelectron spectroscopy. Noteworthy is the fact that the phBe/Mg center is linked with carbon centers through three 7c-2e delocalized σ bonds and three 7c-2e π bonds, making the cluster double aromatic (σ + π) in nature. The bonding between the Be/Mg and outer ring moiety can be best expressed as an electron-sharing σ-bond between the s orbital of Be+/Mg+ and C6M32- followed by three dative interactions involving empty pπ and two in-plane p orbitals of Be/Mg. Furthermore, Lewis basic M centers of the title clusters can be passivated through the complexation with bulky Lewis acid, 9-boratriptycene, lowering the overall reactivity of the cluster, which can eventually open up the possibility of their large-scale syntheses.

Unraveling genomic regions and candidate genes for multiple disease resistance in upland cotton using meta-QTL analysis.

Verticillium wilt (VW), Fusarium wilt (FW) and Root-knot nematode (RKN) are the main diseases affecting cotton production. However, many reported quantitative trait loci (QTLs) for cotton resistance have not been used for agricultural practices because of inconsistencies in the cotton genetic background. The integration of existing cotton genetic resources can facilitate the discovery of important genomic regions and candidate genes involved in disease resistance. Here, an improved and comprehensive meta-QTL analysis was conducted on 487 disease resistant QTLs from 31 studies in the last two decades. A consensus linkage map with genetic overall length of 3006.59 cM containing 8650 markers was constructed. A total of 28 Meta-QTLs (MQTLs) were discovered, among which nine MQTLs were identified as related to resistance to multiple diseases. Candidate genes were predicted based on public transcriptome data and enriched in pathways related to disease resistance. This study used a method based on the integration of Meta-QTL, known genes and transcriptomics to reveal major genomic regions and putative candidate genes for resistance to multiple diseases, providing a new basis for marker-assisted selection of high disease resistance in cotton breeding.

GhSINA1, a SEVEN in ABSENTIA ubiquitin ligase, negatively regulates fiber development in Upland cotton.

Protein ubiquitination is essential for plant growth and responses to the environment. The SEVEN IN ABSENTIA (SINA) ubiquitin ligases have been extensively studied in plants, but information on their roles in fiber development is limited. Here, we identified GhSINA1 in Upland cotton (Gossypium hirsutum), which has a conserved RING finger domain and SINA domain. Quantitative real-time PCR (qRT-PCR) analysis showed that GhSINA1 was preferentially expressed during fiber initiation and elongation, especially during initiation in the fuzzless-lintless cotton mutant. Subcellular localization experiments indicated that GhSINA1 localized to the nucleus. In vitro ubiquitination analysis revealed that GhSINA1 has E3 ubiquitin ligase activity. Ectopic overexpression of GhSINA1 in Arabidopsis thaliana reduced the number and length of root hairs and trichomes. Yeast two-hybrid (Y2H), firefly luciferase complementation imaging (LCI), and bimolecular fluorescence complementation (BiFC) assays demonstrated that the GhSINA1 proteins could interact with each other to form homodimers and heterodimers. Overall, these results suggest that GhSINA1 may act as a negative regulator in cotton fiber development through homodimerization and heterodimerization.

Soft tissue tuberculosis detected by next-generation sequencing: A case report and review of literature.

BACKGROUND: Soft tissue tuberculosis is rare and insidious, with most patients presenting with a localized enlarged mass or swelling, which may be factors associated with delayed diagnosis and treatment. In recent years, next-generation sequencing has rapidly evolved and has been successfully applied to numerous areas of basic and clinical research. A literature search revealed that the use of next-generation sequencing in the diagnosis of soft tissue tuberculosis has been rarely reported. CASE SUMMARY: A 44-year-old man presented with recurrent swelling and ulcers on the left thigh. Magnetic resonance imaging suggested a soft tissue abscess. The lesion was surgically removed and tissue biopsy and culture were performed; however, no organism growth was detected. Finally, Mycobacterium tuberculosis was confirmed as the pathogen responsible for infection through next-generation sequencing analysis of the surgical specimen. The patient received a standardized anti-tuberculosis treatment and showed clinical improvement. We also performed a literature review on soft tissue tuberculosis using studies published in the past 10 years. CONCLUSION: This case highlights the importance of next-generation sequencing for the early diagnosis of soft tissue tuberculosis, which can provide guidance for clinical treatment and improve prognosis.

Two-layer molecular rotors: A zinc dimer rotating over planar hypercoordinate motifs.

Multi-layer molecular rotors represent a class of unique combination of topology and bonding, featuring a barrier-free rotation of one layer with respect to other layers. This emerging fluxional behavior has been found in a few doped boron clusters. Herein, we strongly enrich this intriguing family followed by an effective design strategy, summarized as essential factors: i) considerable electrostatic interactions originated from a strong charge transfer between layers; ii) the absence of strong covalent bonds between layers; and iii) fully delocalized σ/π electrons from at least one layer. We found that planar hypercoordinate motifs consisting of monocyclic boron rings and metals with σ + π dual aromaticity can be regarded as one promising layer, which can support the suspended X2 (X = Zn, Cd, Hg) dimers. By detailed investigations of thermodynamic and kinetic stabilities of 60 species, eventually, MB7 X2 - and MB8 X2 (X = Zn, Cd; M = Be, Ru, Os; Be works only for Zn-based cases) clusters were verified to be the global-minimum two-layer molecular rotors. Especially, their electronic structure analyses vividly confirm the practicability of the electronic structure requirements mentioned above for designing multi-layer molecular rotors.

Influence of the Pre-shock State on the Prognosis of Medical Patients with Sepsis: A Retrospective Cohort Study / 生物医学与环境科学（英文）

OBJECTIVE@#To investigate the effects of the pre-shock state on the mortality of patients with sepsis.@*METHODS@#We enrolled patients with sepsis admitted to the medical intensive care unit of a tertiary care university hospital. These patients were then classified into three groups: sepsis, pre-shock state, and septic shock. The primary outcome was the 28-day mortality rate. The secondary outcomes were the 90-day, 180-day, and 1-year mortality rates.@*RESULTS@#A total of 303 patients (groups: sepsis 135 [44.6%]), pre-shock state (93 [30.7%]), and septic shock (75 [24.8%]) completed the 1-year follow-up. The mortality rates at 28 days, 90 days, and 180 days and 1 year were significantly higher in the pre-shock state group than those of the sepsis group, but significantly lower than those in the septic shock group, especially among older patients. When compared with the pre-shock state group, the sepsis group had significantly lower mortality risks at 28 days, 90 days, and 180 days and 1 year, whereas the sepsis shock group had higher mortality risks at these time points.@*CONCLUSION@#The mortality rates of patients in the pre-shock state were notably different from those of patients with sepsis or septic shock. The introduction of a modified sepsis severity classification, which includes sepsis, pre-shock state, and septic shock, could offer valuable additional prognostic information.

Energy transfer properties of a single-phase Na3Gd(PO4)2:Eu2+,Mn2+ phosphor with excellent thermal stability for w-LEDs.

A high temperature solid state method was used to prepare Na3Gd(PO4)2:Eu2+,Mn2+ phosphors with good thermal stability. The phosphor shows a broadband excitation region of 250-430 nm, which can be matched with the emissions of ultraviolet (UV)/near-ultraviolet (NUV) LED chips for white light emitting diodes (w-LEDs). The energy transfer efficiency is 74.46% from the sensitizer Eu2+ ions to the activator Mn2+ ions, which enhances the intensities of the Na3Gd(PO4)2-based phosphor. In addition, by increasing the Mn2+ doping level in the phosphor, the Na3Gd(PO4)2:Eu2+,Mn2+ phosphor first shows blue light, then turns to white light, and finally emits red light under 365 nm excitation. Besides, the temperature-dependent photoluminescence measurements indicate that the prepared phosphors exhibit good thermal stability. W-LEDs fabricated by combining a 365 nm chip with the Na3Gd(PO4)2:Eu2+,Mn2+ phosphor exhibit bright white light, which has a high color rendering index (CRI) = 91.5, and a relatively low correlated color temperature (CCT) = 5198 K. Moreover, the CIE point is calculated to be at (0.3337, 0.3465), which is located in the white light region. These results indicate that the as-prepared phosphors can be considered as potential candidates for UV/NUV light-excited w-LED applications.

MOF-Derived Long Spindle-like Carbon-Coated Ternary Transition-Metal-Oxide Composite for Lithium Storage.

Fe3O4 is a promising alternative for next-generation lithium-ion batteries (LIBs). However, its poor cycle stability due to the large volume effect during cycling and poor conductivity hinders its application. Herein, we have successfully designed and prepared a carbon-coated ternary transition-metal-oxide composite (noted as (FeCoNi)3O4@C), which is derived from FeCoNi-MOF-74 (denoted as FeCoNi-211-24). (FeCoNi)3O4@C perfectly inherited the long spindle-shaped precursor structure, and (FeCoNi)3O4 particles grew in situ on the precursor surface. The ordered particles and the carbon-coated structure inhibited the agglomeration of particles, improving the material's cycle stability and conductivity. Therefore, the electrode exhibited excellent electrochemical performance. Specifically, (FeCoNi)3O4@C-700 presented excellent initial discharge capacity (763.1 mAh g-1 at 0.2 A g-1), high initial coulombic efficiency (73.8%), excellent rate capability, and cycle stability (634.6 mAh g-1 at 0.5 A g-1 after 505 cycles). This study provides a novel idea for developing anode materials for LIBs.

Distinct Response of Circulating microRNAs to the Treatment of Pancreatic Cancer Xenografts with FGFR and ALK Kinase Inhibitors.

Pancreatic adenocarcinoma is typically detected at a late stage and thus shows only limited sensitivity to treatment, making it one of the deadliest malignancies. In this study, we evaluate changes in microRNA (miR) patterns in peripheral blood as a potential readout of treatment responses of pancreatic cancer to inhibitors that target tumor-stroma interactions. Mice with pancreatic cancer cell (COLO357PL) xenografts were treated with inhibitors of either fibroblast growth factor receptor kinase (FGFR; PD173074) or anaplastic lymphoma kinase receptor (ALK; TAE684). While both treatments inhibited tumor angiogenesis, signal transduction, and mitogenesis to a similar extent, they resulted in distinct changes in circulating miR signatures. Comparison of the miR pattern in the tumor versus that in circulation showed that the inhibitors can be distinguished by their differential impact on tumor-derived miRs as well as host-derived circulating miRs. Distinct signatures that include circulating miR-1 and miR-22 are associated with the efficacy of ALK and FGFR inhibition, respectively. We propose that monitoring changes in circulating miR profiles can provide an early signature of treatment response or resistance to pathway-targeted drugs, and thus provide a non-invasive measurement to rapidly assess the efficacy of candidate therapies.

Simultaneous Spectral Tuning and Thermal Stability Adjustment in Ca8ZnGa(1-x)Lax(PO4)7:Eu2+ Phosphors.

The modifications of local structure in solid solution are a crucial step to regulate the photoluminescence properties of rare-earth ion-based phosphors. However, the structural diversity of host matrices and the uncertain occupation of activators make it challenging to obtain phosphors with both high stability and tailored emission. Herein, We synthesized a series of ß-Ca3(PO4)2-type Ca8ZnGa(1-x)Lax(PO4)7:Eu2+ solid solution phosphors by design. By modifying the Ga/La ratio, controllable regulation of the emission spectrum and thermal stability of the phosphors can be achieved at the same time. The introduction of La3+ can regulate the crystal field splitting strength of the Eu2+ activators, causing redshifts in the emission spectrum while increasing Ga3+ content will lead to enhanced energy transfer between the oxygen vacancy and Eu2+, as well as improved thermal stability. Through local structure modification, the spectrum and thermal stability of phosphors can be facilely tuned. The results indicate that this series of phosphors have versatile potentials in various applications.

Polydopamine Nanocluster Embedded Nanofibrous Membrane via Blow Spinning for Separation of Oil/Water Emulsions.

Developing a porous separation membrane that can efficiently separate oil-water emulsions still represents a challenge. In this study, nanofiber membranes with polydopamine clusters polymerized and embedded on the surface were successfully constructed using a solution blow-spinning process. The hierarchical surface structure enhanced the selective wettability, superhydrophilicity in air (≈0°), and underwater oleophobicity (≈160.2°) of the membrane. This membrane can effectively separate oil-water emulsions, achieving an excellent permeation flux (1552 Lm-2 h-1) and high separation efficiency (~99.86%) while operating only under the force of gravity. When the external driving pressure was increased to 20 kPa, the separation efficiency hardly changed (99.81%). However, the permeation flux significantly increased to 5894 Lm-2 h-1. These results show that the as-prepared polydopamine nanocluster-embedded nanofiber membrane has an excellent potential for oily wastewater treatment applications.

Untreated Prior Pulmonary Tuberculosis Adversely Affects Pregnancy Outcomes in Infertile Women Undergoing / 生物医学与环境科学（英文）

Objective@#Prior pulmonary tuberculosis (PTB) on chest X-ray (CXR) was commonly found in infertile patients receiving examinations before @*Method@#We conducted a retrospective cohort study of 14,254 infertile patients who had received IVF-ET at Peking University Third Hospital in 2017. Prior PTB was defined as the presence of signs suggestive of old or inactive PTB on CXR, with or without a clinical TB history. Patients who had prior PTB on CXR but had not received a clinical diagnosis and anti-TB therapy were included for analysis. Live birth, clinical pregnancy, and miscarriage rates were compared between the untreated PTB and non-PTB groups.@*Results@#The untreated PTB group had significantly lower clinical pregnancy (31.7% @*Conclusions@#Untreated PTB was associated with adverse pregnancy outcomes after IVF-ET, especially in patients with unexplained infertility, highlighting the clinical significance of PTB in this specific patient population.

[Cross-resistance and the underlying mechanisms of clothianidin resistant population of Frankliniella occidentalis to insecticides]. / 西花蓟马抗噻虫胺种群对杀虫剂的交互抗性及机制.

Clothianidin, belonging to neonicotinoid insecticide with systemic and contact mechanisms, is used to control the invasive pest Frankliniella occidentalis. To identify the resistance risk, we examined the cross-resistance to multiple insecticides and mechanisms of clothianidin resistant population of F. occidentalis. The results showed that F. occidentalis developed a high level of resis-tance to clothianidin (56.8-fold) after selecting for 45 generations. The resistant population of F. occidentalis had medium level of cross-resistance to thiamethoxam, imidacloprid, chlorpyrifos, cyhalothrin and emamectin benzoate (18.6>RR50>11.3), and the low level of cross-resistance to phoxim and methomyl, but no cross-resistance to chlorfenapyr and spinosad. The synergists piperonyl butoxide (PBO) and triphenyl phosphate (TPP) had significant synergistic effects on clothianidin in killing the resistant population (CL), Yunnan wild population (YN) and susceptible population (S). Compared with the sensitive population, the CL populations had significantly increased activities of mixed-functional oxidases P450(3.6-fold), b5(2.9-fold) and O-demethylase (4.9-fold), and carboxylesterase (2.5-fold), with no significant difference in the activities of glutathione S-transferases among CL and S populations. The results highlight the role of increasing mixed-functional oxidases and carboxylesterase in the resistance of F. occidentalis to clothianidin.

[Resistance risk and resistance stability of Frankliniella occidentalis to nitenpyram, clothianidin and thiamethoxam]. / 西花蓟马对烯啶虫胺、噻虫胺和噻虫嗪的抗性风险和抗性稳定性.

To effectively control the damage of Frankliniella occidentalis (Pergande), we evalutated the resistance risk and resistance stability of F. occidentalis to nitenpyram, clothianidin and thiamethoxam. With the method of dipping Phaseolus vuglaris, we selected the resistance populations from the susceptible population with nitenpyram, clothianidin and thiamethoxam, respectively. Both the resistance inheritance and resistance risk were analyzed with the resistance reality hereditary. After 30 generations' selections, the selected-populations showed high level of insecticide resistance to nitenpyram, clothianidin and thiamethoxam, with a resistance ratio of 44.7-fold, 45.5-fold, and 32.7-fold, respectively. The development rate of resistance to clothianidin, nitenpyram, and thiamethoxam reduced in turn, with a resistance reality heritability of 0.1503, 0.1336 and 0.1258, respectively. Stopping selection for 10 continuously generations, the resistance levels of selection resis-tance populations declined slowly, but could not regain the original susceptibility to nitenpyram, clothianidin and thiamethoxam. After resistance selection, the sensitivity of F. occidentalis nymphs to clothianidin, nitenpyram, and thiamethoxam was significantly higher than that of adults. F. occidentalis had the great potential to gain high level resistance to nitenpyram, clothianidin and thiamethoxam. Compared with other two insecticides, the resistance of F. occidentalis to thiamethoxam increased slower and decreased faster. Therefore, using thiamethoxam in nymph stage might be beneficial to effectively control F. occidentalis.

Genetic structure, gene flow pattern, and association analysis of superior germplasm resources in domesticated upland cotton (Gossypium hirsutum L.).

Gene flow patterns and the genetic structure of domesticated crops like cotton are not well understood. Furthermore, marker-assisted breeding of cotton has lagged far behind that of other major crops because the loci associated with cotton traits such as fiber yield and quality have scarcely been identified. In this study, we used 19 microsatellites to first determine the population genetic structure and patterns of gene flow of superior germplasm resources in upland cotton. We then used association analysis to identify which markers were associated with 15 agronomic traits (including ten yield and five fiber quality traits). The results showed that the upland cotton accessions have low levels of genetic diversity (polymorphism information content = 0.427), although extensive gene flow occurred among different ecological and geographic regions. Bayesian clustering analysis indicated that the cotton resources used in this study did not belong to obvious geographic populations, which may be the consequence of a single source of domestication followed by frequent genetic introgression mediated by human transference. A total of 82 maker-trait associations were examined in association analysis and the related ratios for phenotypic variations ranged from 3.04% to 47.14%. Interestingly, nine SSR markers were detected in more than one environmental condition. In addition, 14 SSR markers were co-associated with two or more different traits. It was noteworthy that NAU4860 and NAU5077 markers detected at least in two environments were simultaneously associated with three fiber quality traits (uniformity index, specific breaking strength and micronaire value). In conclusion, these findings provide new insights into the population structure and genetic exchange pattern of cultivated cotton accessions. The quantitative trait loci of domesticated cotton identified will also be very useful for improvement of yield and fiber quality of cotton in molecular breeding programs.