Deficiency of primate-specific SSX1 induced asthenoteratozoospermia in infertile men and cynomolgus monkey and tree shrew models.

Primate-specific genes (PSGs) tend to be expressed in the brain and testis. This phenomenon is consistent with brain evolution in primates but is seemingly contradictory to the similarity of spermatogenesis among mammals. Here, using whole-exome sequencing, we identified deleterious variants of X-linked SSX1 in six unrelated men with asthenoteratozoospermia. SSX1 is a PSG expressed predominantly in the testis, and the SSX family evolutionarily expanded independently in rodents and primates. As the mouse model could not be used for studying SSX1, we used a non-human primate model and tree shrews, which are phylogenetically similar to primates, to knock down (KD) Ssx1 expression in the testes. Consistent with the phenotype observed in humans, both Ssx1-KD models exhibited a reduced sperm motility and abnormal sperm morphology. Further, RNA sequencing indicated that Ssx1 deficiency influenced multiple biological processes during spermatogenesis. Collectively, our experimental observations in humans and cynomolgus monkey and tree shrew models highlight the crucial role of SSX1 in spermatogenesis. Notably, three of the five couples who underwent intra-cytoplasmic sperm injection treatment achieved a successful pregnancy. This study provides important guidance for genetic counseling and clinical diagnosis and, significantly, describes the approaches for elucidating the functions of testis-enriched PSGs in spermatogenesis.

CuInS2/Red Phosphorus Nanosheet Interleaved Heterostructures with Improved Interfacial Charge Transfer for Photoelectrochemical Aptasensing.

Accelerating the migration of interfacial carriers in heterojunctions is crucial for achieving highly sensitive photoelectrochemical (PEC) sensing. In this study, we developed three-dimensional (3D)/two-dimensional (2D) CuInS2/red phosphorus nanosheet (CuInS2/RP NS) n-n heterojunction functional materials with enhanced interfacial charge transfer capabilities for PEC sensing. The 3D CuInS2 serves as a conductive layer, providing excellent electronic conductivity and superior electron absorption and transport properties. In contrast, the ultrathin RP NS acts as a transport layer that enhances carrier mobility. The 3D/2D heterojunction ensures a large interface contact surface, shortening the carrier transport distance. A well-aligned band position generates a substantial built-in electric field, providing a significant driving force for efficient carrier separation and migration, thereby improving response sensitivity. A PEC aptamer sensor was constructed based on the synthesized heterostructure for ciprofloxacin detection. The detection limit of the CuInS2/RP NS aptamer sensor for ciprofloxacin is 2.03 × 10-15 mg·mL-1, with a linear range from 1.0 × 10-14 to 1.0 × 10-5 mg·mL-1. This work presents a strategy for enhancing the photoelectric response by modulating the interface structure of heterojunctions, thereby opening new prospects for the application of highly sensitive PEC sensors in antibiotic detection.

Deciphering the In Situ Reconstruction of Metal Phosphide/Nitride Dual Heterostructures for Robust Alkaline Hydrogen Evolution Above 3 A cm-2.

Hydrogen evolution reaction (HER) in neutral or alkaline electrolytes is appealing for sustainable hydrogen production driven by water splitting, but generally suffers from unsatisfied catalytic activities at high current densities owing to extra kinetic energy barriers required to generate protons through water dissociation. In response, here, a competitive Ni3 N/Co3 N/CoP electrocatalyst with multifunctional interfacial sites and multilevel interfaces, in which Ni3 N/CoP performs as active sites to boost initial water dissociation and Co3 N/CoP accelerates subsequent hydrogen adsorption process as confirmed by density functional theory calculations and in situ X-ray photoelectron spectroscopy analysis, is reported. This hybrid catalyst possesses extraordinary HER activity in base, featured by extremely low overpotentials of 115 and 142 mV to afford 500 and 1000 mA cm-2 , respectively, outperforming most ever-reported metal phosphides-based catalysts. This catalyst presents an ultrahigh current density of 3545 mA cm-2 by a factor of 4.96 relative to noble Pt/C catalysts (715 mA cm-2 ) at 0.2 V. Assembled with Fe(PO3 )2 /Ni2 P anode, industrial-level current densities of 500/1000 mA cm-2 at ultralow cell voltages of 1.62/1.66 V for overall water electrolysis with outstanding long-term stability are actualized. More interestingly, this hybrid catalyst also performs well in acidic, neutral freshwater, and seawater requiring relatively low overpotentials of 140, 290, and 331 mV to reach 500 mA cm-2 . Particularly, this catalyst can withstand electrochemical corrosion without obvious activity decay at the industrial-level current densities for over 100 h in base. This work provides a cornerstone for the construction of advanced catalysts operated in different pH environments.

Prognostic nomograms for breast cancer with lung metastasis: a SEER-based population study.

BACKGROUND: Lung metastasis is a significant adverse predictor of prognosis in patients with breast cancer. Accurate estimation for the prognosis of patients with lung metastasis and population-based validation for the models are lacking. In the present study, we aimed to establish the nomogram to identify prognostic factors correlated with lung metastases and evaluate individualized survival in patients with lung metastasis based on SEER (Surveillance, Epidemiology, and End Results) database. METHODS: We selected 1197 patients diagnosed with breast cancer with lung metastasis (BCLM) from the SEER database and randomly assigned them to the training group (n = 837) and the testing group (n = 360). Based on univariate and multivariate Cox regression analysis, we evaluated the effects of multiple variables on survival in the training group and constructed a nomogram to predict the 1-, 2-, and 3-year survival probability of patients. The nomogram were verified internally and externally by Concordance index (C-index), Net Reclassification (NRI), Integrated Discrimination Improvement (IDI), Decision Curve Analysis (DCA), and calibration plots. RESULTS: According to the results of multi-factor Cox regression analysis, age, histopathology, grade, marital status, bone metastasis, brain metastasis, liver metastasis, human epidermal growth factor receptor 2 (HER2), estrogen receptor (ER), progesterone receptor (PR), surgery, neoadjuvant therapy and chemotherapy were considered as independent prognostic factors for patients with BCLM. The C-index in the training group was 0.719 and the testing group was 0.695, respectively. The AUC values of the 1-, 2-, and 3-year prognostic nomogram in the training group were 0.798, 0.790 and 0.793, and the corresponding AUC values in the testing group were 0.765, 0.761 and 0.722. The calculation results of IDI and NRI were shown. The nomograms significantly improved the risk reclassification for 1-, 2-, and 3-year overall mortality prediction compared with the AJCC 7th staging system. According to the calibration plot, nomograms showed good consistency between predicted and actual overall survival (OS) values for the patients with BCLM. DCA showed that nomograms had better net benefits at different threshold probabilities at different time points compared with the AJCC 7th staging system. CONCLUSIONS: Nomograms that predicted 1-, 2-, and 3-year OS for patients with BCLM were successfully constructed and validated to help physicians in evaluating the high risk of mortality in breast cancer patients.

Association between annual changes and visit-to-visit variability of serum uric acid and the kidney outcome in a general population.

BACKGROUND: To determine whether variability of serum uric acid (UA) is associated with risk of chronic kidney disease (CKD) in a healthy population. METHODS: Retrospective, longitudinal cohort study was conducted at a health examination center in China. The study enrolled subjects who had a minimum of three visits between 2011 and 2018. We assessed UA change and visit-to-visit UA variability including standard deviation (SD), coefficient of variation (CV), variability independent of the mean (VIM), and average real variability (ARV). Rapid estimated glomerular filtration rate (eGFR) decline was defined by annual eGFR change < -4 mL/min/1.73 m2/year. We conducted a multivariable-adjusted logistic regression analysis. RESULTS: Ten thousand seven hundred and thirty-eight participants were included. During 4.43 ± 1.31 years follow-up, there were 535 cases with rapid eGFR decline and 240 cases developed CKD. Compared to the non-rapid eGFR decline group and non-CKD group, the UA annual changes and variability were higher in the rapid eGFR decline group and CKD group. The highest quartile of UA annual changes and variability showed a higher incident rate of rapid eGFR decline and that of CKD. After adjusting for covariates, OR for eGFR rapid decline in UA variability were 1.69 [1.53, 1.86] for annual changes of UA, 1.17 [1.08, 1.27] for SD of UA, 1.16 [1.06, 1.25] for CV of UA, 1.16 [1.07, 1.25] for VIM of UA, and 1.10 [1.02, 1.19] for ARV of UA. Consistent results were observed when CKD is used as the outcome. CONCLUSIONS: Higher variability of serum UA was independently associated with the risk of kidney impairment.

Characteristics of inhibitory active substances produced by Pseudoalteromonas SW-1.

To confirm the antagonistic activity characterization of the strain Pseudoalteromonas SW-1 (P. SW-1), its cell-free supernatant (CFS) was studied against a clam pathogenic strain of Vibrio Alginolyticu MP-1 (V.MP-1). The CFS of P. SW-1 exhibited evident antagonistic activities against the pathogens, and the absorbance value (600 nm) of V. MP-1 remained at a lower level at 24 h when compared with the control. The results showed that the inhibitory activities of strain P. SW-1 CFS showed differences after treatment with heat, acid and alkali, and proteinase K. The CFS of P. SW-1 inhibitory activities decreased after treatment with heat, but the inhibitory activities of strain P. SW-1 CFS were still effective after treatment with proteinase K for 24 h. The acid and alkali treatments could increase the inhibitory activities of strain P. SW-1 CFS. Therefore, the ammonium sulfate precipitation test also indicated that P. SW-1 could produce some active protein compounds to antagonize pathogenic V. MP-1.

Correction: Wang et al. Visible Light Motivated the Photocatalytic Degradation of P-Nitrophenol by Ca2+-Doped AgInS2. Molecules 2024, 29, 361.

In the original publication [...].

Visible Light Motivated the Photocatalytic Degradation of P-Nitrophenol by Ca2+-Doped AgInS2.

4-Nitrophenol (4-NP) is considered a priority organic pollutant with high toxicity. Many authors have been committed to developing efficient, green, and environmentally friendly technological processes to treat wastewater containing 4-NP. Here, we investigated how the addition of Ca2+ affects the catalytic degradation of 4-NP with AgInS2 when exposed to light. We synthesized AgInS2 (AIS) and Ca2+-doped AgInS2 (Ca-AIS) with varying amounts of Ca2+ using a low-temperature liquid phase method. The SEM, XRD, XPS, HRTEM, BET, PL, and UV-Vis DRS characteristics were employed to analyze the structure, morphology, and optical properties of the materials. The effects of different amounts of Ca2+ on the photocatalytic degradation of 4-NP were investigated. Under visible light illumination for a duration of 120 min, a degradation rate of 63.2% for 4-Nitrophenol (4-NP) was achieved. The results showed that doping with an appropriate amount of Ca2+ could improve the visible light catalytic activity of AIS. This work provides an idea for finding suitable cheap alkaline earth metal doping agents to replace precious metals for the improvement of photocatalytic activities.

Janus kinase inhibitor Tofacitinib alleviated acute hepatitis induced by lipopolysaccharide/D-galactosamine in mice.

BACKGROUND: The Janus kinase (JAK) is a crucial intracellular signaling hub for numerous cytokines, which is extensively involved in the activation of inflammatory cascade and the induction of inflammatory injury. JAK inhibition provides protective effects in several inflammation-based disorders, but the potential effects of JAK inhibitor in inflammation-based acute hepatitis remain to be investigated. METHODS AND RESULTS: Acute hepatitis is induced by Lipopolysaccharide/D-galactosamine (LPS/D-Gal) in mice with or without the JAK inhibitor Tofacitinib administration. The degree of liver injury, the production of pro-inflammatory cytokines and induction of hepatocytes apoptosis were determined. The results indicated that treatment with Tofacitinib decreased the levels of aminotransferases, attenuated the histological abnormalities in liver and decreased the plasma levels of TNF-α and IL-6 in LPS/D-Gal-insulted mice. In addition, Tofacitinib suppressed the activation of the caspase cascade, decreased the level of cleaved caspase-3, and reduced the count of TUNEL-positive cells. CONCLUSION: Treatment with Tofacitinib alleviated LPS/D-Gal-induced acute hepatitis. JAK maybe become a promising target for the control of inflammation-based liver disorders.

ASA-BiSeNet: improved real-time approach for road lane semantic segmentation of low-light autonomous driving road scenes.

The solution to the problem of road environmental perception is one of the essential prerequisites to realizing the autonomous driving of intelligent vehicles, and road lane detection plays a crucial role in road environmental perception. However, road lane detection in complex road scenes is challenging due to poor illumination conditions, the occlusion of other objects, and the influence of unrelated road markings. It also hinders the commercial application of autonomous driving technology in various road scenes. In order to minimize the impact of illumination factors on road lane detection tasks, researchers use deep learning (DL) technology to enhance low-light images. In this study, road lane detection is regarded as an image segmentation problem, and road lane detection is studied based on the DL approach to meet the challenge of rapid environmental changes during driving. First, the Zero-DCE++ approach is used to enhance the video frame of the road scene under low-light conditions. Then, based on the bilateral segmentation network (BiSeNet) approach, the approach of associate self-attention with BiSeNet (ASA-BiSeNet) integrating two attention mechanisms is designed to improve the road lane detection ability. Finally, the ASA-BiSeNet approach is trained based on the self-made road lane dataset for the road lane detection task. At the same time, the approach based on the BiSeNet approach is compared with the ASA-BiSeNet approach. The experimental results show that the frames per second (FPS) of the ASA-BiSeNet approach is about 152.5 FPS, and its mean intersection over union is 71.39%, which can meet the requirements of real-time autonomous driving.

Effects of intraoperative esketamine addition on gastrointestinal function after benign gynaecological laparoscopic surgery: a double-blind, randomized controlled study.

BACKGROUND: Gastrointestinal hypokinesis can occur transiently after benign gynecologic surgery. Opioids cause the side effect of postoperative gastrointestinal hypokinesis, but an opioid-sparing anaesthetic protocol based on esketamine reduces intraoperative opioid consumption. Therefore, this study hypothesised that an opioid-sparing anaesthetic protocol based on esketamine would shorten the gastrointestinal function recovery time after benign gynaecological laparoscopic surgery. METHODS: This was a prospective randomized controlled double-blind study conducted in a single centre. All patients scheduled for elective benign laparoscopic gynaecological surgery at Xing'an Meng People's Hospital, Inner Mongolia Autonomous Region, from November 2021 to April 2022 were consecutively enrolled and randomly divided into the opioid-sparing anaesthesia group (Group OS) and the conventional anaesthesia group (Group C). Postoperative first exhaust time, feeding time and postoperative nausea and/or vomiting (PONV) were analyzed in both groups. RESULTS: A total of 71 patients were enrolled in this study, including 35 in Group OS and 36 in Group C. The general condition, operative time, type of surgery, intraoperative bleeding, intraoperative fluid volume and intraoperative urine volume were not statistically different between the two groups. Compared with Group C, significantly shorter first postoperative flatus time (11 [8, 14] h vs. 14 [11, 18], p = 0.003) and anaesthesia resuscitation time (7 [6, 9] h vs. 9 [7, 11] h, p = 0.013)were observed in the OS group. The incidence of PONV in Group OS was significantly lower compared with Group C (11.4% vs. 41.7%, p = 0.007). CONCLUSION: The esketamine-based opioid-sparing anaesthetic protocol can shorten the postoperative first flatus time after benign laparoscopic surgery in gynaecology, and reduce the incidence of PONV. In addition, the application of esketamine may reduce the postoperative opioid dose requirement of patients. TRIAL REGISTRATION: This study was registered with the China Clinical Trials Registry (registration number: ChiCTR2100052528, 30/10/2021).

Physiological responses of date palm (Phoenix dactylifera) seedlings to seawater and flooding.

In their natural environment along coast lines, date palms are exposed to seawater inundation and, hence, combined stress by salinity and flooding. To elucidate the consequences of this combined stress on foliar gas exchange and metabolite abundances in leaves and roots, date palm seedlings were exposed to flooding with seawater and its major constituents under controlled conditions. Seawater flooding significantly reduced CO2 assimilation, transpiration and stomatal conductance, but did not affect isoprene emission. A similar effect was observed upon NaCl exposure. By contrast, flooding with distilled water or MgSO4 did not affect CO2 /H2 O gas exchange or stomatal conductance significantly, indicating that neither flooding itself, nor seawater sulfate, contributed greatly to stomatal closure. Seawater exposure increased Na and Cl contents in leaves and roots, but did not affect sulfate contents significantly. Metabolite analyses revealed reduced abundances of foliar compatible solutes, such as sugars and sugar alcohols, whereas nitrogen compounds accumulated in roots. Reduced transpiration upon seawater exposure may contribute to controlling the movement of toxic ions to leaves and, therefore, can be seen as a mechanism to cope with salinity. The present results indicate that date palm seedlings are tolerant towards seawater exposure to some extent, and highly tolerant to flooding.

A regulatory role for CD72 expression on B cells and increased soluble CD72 in primary Sjogren's syndrome.

BACKGROUND: CD72, a co-receptor of B cell receptor (BCR), has been reported to have both positive and negative effects on B cell functions in several immunological diseases. The B cell plays an important role in the pathogenesis of primary Sjogren's syndrome (pSS). However, whether CD72 is involved in the process remains unknown. This study aimed to observe the possible role of CD72 in the pathogenesis of pSS. RESULTS: A total of 60 cases who fulfilled the American-European Consensus Group (AECG) criteria for the diagnosis of pSS and 61 gender and age-matched healthy controls were recruited in this study. The percentage of CD72+ B cells was 85.31 ± 8.37% in pSS patients and 76.91 ± 8.50% in healthy controls(p < 0.001). The percentage of CD72+ B cells was correlated to serum IgG levels in patients [ß = 0.018(0.001-0.036), p = 0.034]. The level of serum soluble CD72 was significantly higher in pSS patients than the one in healthy controls (0.41 (0.29) vs 0.07 (0.08) ng/mL, p < 0.001). CONCLUSIONS: The percentage of CD72+ B cells was upregulated in pSS patients and was correlated to the serum IgG level, which revealed the hyperactivity of B cells in this disease. The serum soluble CD72 level was also increased in pSS patients. These results indicated a potential role of CD72 in the pathogenesis of pSS.

Complete genome sequence of a new member of the genus Badnavirus from red pitaya (Hylocereus polyrhizus).

Here, we report a circular double-stranded DNA virus from red pitaya (Hylocereus polyrhizus). The complete genome sequence is 7,837 nt in length and shares 98.7% nucleotide sequence identity with epiphyllum mottle-associated virus (EpMoaV) and 40.4-54.6% with other members of the genus Badnavirus. It has four open reading frames (ORFs), encoding putative proteins of 19.9, 14.8, 225.7 and 14.2 kDa, respectively. The reverse transcriptase (RT)-ribonuclease H (RNase H) region exhibits less than 70.5% nucleotide sequence identity to RT-RNase H of other badnaviruses, and 99.7% to that of EpMoaV. Phylogenetic analysis revealed that the virus from this study and EpMoaV form a single group. Consequently, we propose this virus as a new member of the genus Badnavirus in the family Caulimoviridae and have named it "pitaya badnavirus 1" (PiBV1). PiBV1 and EpMoaV should be considered two isolates of a badnavirus that infects members of the family Cactaceae.

Echinacoside prevents hypoxic pulmonary hypertension by regulating the pulmonary artery function.

Hypoxic pulmonary hypertension (HPH) is a progressive and irreversible disease that reduces survival. Echinacoside is a phenylethanoid glycoside from Tibetan herbs known for its vasorelaxant effect and for inhibiting the proliferation of rat pulmonary arterial smooth muscle cells. This study aimed to investigate the effect of echinacoside on HPH. Sprague Dawley rats were housed in a hypobaric hypoxia chamber (4500 m) for 28 days to obtain the HPH model. Echinacoside (3.75, 7.5, 15, 30 and 40 mg/kg) was administered by intraperitoneal injection from the 1st to the 28th day. The mean pulmonary artery pressure (mPAP), right ventricular hypertrophy index, hemoglobin, hematocrit, red blood cell concentration and morphological change of pulmonary arteries were evaluated. Vascular perfusion assay was used to assess the pulmonary artery function. Echinacoside reduced mPAP, hemoglobin, hematocrit, right ventricular hypertrophy index and mean wall thickness% of pulmonary arteries in HPH rats. It significantly increased maximum vasoconstriction percentage of pulmonary arteries induced by noradrenaline in a dose-dependent manner. In addition, it improved the responsiveness of pulmonary arteries to acetylcholine and sodium nitroprusside. Therefore, Echinacoside might be an effective treatment against HPH, since it regulated pulmonary artery endothelium and smooth muscle layer function and improved the remodeling of pulmonary artery.

Metformin scavenges formaldehyde and attenuates formaldehyde-induced bovine serum albumin crosslinking and cellular DNA damage.

Formaldehyde (FA) can be produced in the environment and by cell metabolism and has been classified as a carcinogen in animals and humans. Metformin is the most commonly used drug for the treatment of type 2 diabetes. Metformin also has potential benefit in cancer prevention and treatment. The aim of this study was to determine whether metformin can directly react with FA and attenuate its toxicity in vitro. Metformin was incubated at pH 7.4 and 37°C in the presence of FA, and the reaction mixture was analyzed by UV spectrophotometry, high-performance liquid chromatography (HPLC), and mass spectrometry. Fluorescence spectrophotometry, immunofluorescence, and western blot were used to measure FA-induced bovine serum albumin (BSA) crosslinking and DNA damage in HepG2 cells treated with or without metformin. According to the HPLC and mass spectrometry data, we speculate that the reaction of metformin with FA (1:1) initially results in the formation of a conjugated intermediate followed by the subsequent generation of a stable six-membered ring structure. Correspondingly, metformin attenuated FA-induced fluorescence in BSA as well as the aggregation of γH2AX in HepG2 cells. These results suggest that metformin can protect protein and DNA damage induced by FA at least partly through a direct reaction process.

Preparative separation of isoquinoline alkaloids from Corydalis impatiens using a middle-pressure chromatogram isolated gel column coupled with two-dimensional liquid chromatography.

We established a two-dimensional strong cation exchange/reversed-phase liquid chromatography protocol to isolate and purify isoquinoline alkaloids from Corydalis impatiens. Isoquinoline alkaloids were first enriched from a C. impatiens extract in which liposoluble components were removed using a medium-pressure chromatographic tower containing middle chromatogram isolated gel. A strong cation exchange column was employed to separate and obtain 30 fractions. We chose fractions 22-29 for reversed-phase liquid chromatography purification using characteristic isoquinoline alkaloid ultraviolet absorption spectra. Several isoquinoline alkaloid fractions (22-29) were further separated, and those of low resolution were isolated via two-dimensional liquid chromatography in the orthogonal plane. A total of eight novel isoquinoline alkaloids with characteristic ultraviolet spectra were obtained from C. impatiens. We thus demonstrate the benefits of off-line two-dimensional strong cation exchange/reversed-phase liquid chromatography to isolate isoquinoline alkaloids from C. impatiens.

Morphological Observation and Comparative Transcriptomic Analysis of Clostridium perfringens Biofilm and Planktonic Cells.

Bacterial biofilms can enhance survival in adverse environments and promote infection. However, little is known about biofilm formation by Clostridium perfringens. To better characterize this process, we used SEM to observe the surfaces of C. perfringens biofilms after 12, 24, 48, and 72 h of incubation. Biofilm cells appeared to be encased in a dense matrix material, and the total biomass of the biofilm increased with incubation time. To gain insight into the differentially expressed genes (DEGs) between biofilm and planktonic cells, we carried out comparative transcriptomic analysis using RNA sequencing. In total, 91 genes were significantly differentially expressed, with 40 being up-regulated and 51 down-regulated. In particular, genes encoding sortase, ribosomal proteins, and ATP synthase were up-regulated in biofilms, while genes coding for clostripain and phospholipase C were down-regulated. To validate the RNA sequencing results, qRT-PCR analysis was performed using five randomly selected DEGs. Results showed that all five genes were up-regulated, which was in accordance with the RNA sequencing results. To examine the functional differences, the DEGs were characterized by GO and KEGG pathway enrichment analyses. Results showed that the up-regulated genes were divided into 32 significantly enriched GO terms, with "macromolecular complex" being the most common. Oxidative phosphorylation was the only significantly enriched pathway, suggesting that ATP is required for biofilm stability. This study provides valuable insights into the morphology and transcriptional regulation of C. perfringens during biofilm formation, and will be useful for understanding and developing biofilm-based processes.

Largely different contents of terpenoids in beef red-flesh tangerine and its wild type.

BACKGROUND: Niurouhong (Citrus reticulata Blanco. Niurouhong) (NRH) is a spontaneous beef-red flesh mutant with distinctive flavor compared with its wild type orange-red flesh Zhuhongju (ZHJ). To illustrate the biochemical mechanism of its special flesh color and flavor, fruits at commercial mature stage were used to profile the volatiles in the flavedo and determine the levels of carotenoids, limonoid aglycones and phytohormones in the juice sacs in two seasons. RESULTS: Our results showed the content of total volatile terpenoids in NRH was 1.27-fold that in ZHJ. The components of volatiles were found to be common between the two tangerines. This result indicates that the distinctive flavor of NRH might not be derived from the presence/absence of specific volatiles; instead, it was derived from the altered concentrations or balance of α-citral, ß-citral, 2-cyclohexen-1-one, (S)-3-methyl-6-(1-methylethenyl) and n-hexadecanoic acid. Analyses of the contents of total and specific carotenoids indicated that the beef-red color of NRH flesh might be largely attributed to the over accumulation of ß-cryptoxanthin and ß-carotene. However, lower ABA level was found in NRH than in ZHJ, reflecting a possible feedback regulation of ABA biosynthesis on carotenogenesis and the balance in the metabolism among terpenoids. CONCLUSIONS: Collectively, our study suggested that the MEP pathway was enhanced in NRH tangerine. However, a certain unknown co-regulatory mechanism might be present in the metabolism pathway of secondary metabolites (especially terpenoids) in beef-red flesh mutant. Our study provides new insights into the regulatory network of terpenoid metabolism and mutation mechanism of red-fleshed citrus.

In vivo fate of lipid-silybin conjugate nanoparticles: Implications on enhanced oral bioavailability.

Lipid-drug conjugates (LDCs) of a poorly soluble and poorly permeable drug silybin (SB) and lipids with different chain lengths (6C, 12C, 18C) are synthesized and formulated into solid lipid nanoparticles (SLNs). The in vivo fate of LDCs as well as SLNs is investigated by tracking either SB or LDCs or SLNs. LDCs are prone to be hydrolyzed by lipases either in simulated gastrointestinal media or in Caco-2 cell lines in a lipid chain length-dependent mode. The oral bioavailability of SB is enhanced by 5-7-fold in comparison with a fast-release formulation. No integral LDCs are detected in plasma confirms the readily degradable nature of LDCs. The absorption of LDCs by enteric epithelia and subsequent transportation into circulation might play a leading role in absorption enhancement, whereas the contribution of then M-cell pathway is not as remarkable. A shorter lipid chain favors earlier lipolysis and faster absorption along the intestine-to-circulation path.