Three-dimensional morphological analysis and clinical application of ankle joint in Chinese population based on CT reconstruction.

PURPOSE: To study the anatomical features of the ankle joint in Chinese northeast healthy adults and provide accurate data for the design of the total ankle arthroplasty (TAA) prosthesis. METHODS: Computer tomography (CT) images from 156 healthy subjects, 86 males and 70 females, were collected and reconstructed through Mimics software. The 3D morphology of the distal tibia/fibula section and the whole talar was analyzed by measuring 28 parameters including maximal tibial thickness (MTiTh), anterior-posterior inclination angle, trochlea tali width (TaW), distal tibial width (TiW) and trochlea tali arc chode length (TaAL) and calculating MTiTh/TiW, TaAL/TaW. Gender difference and accuracy of CT images were evaluated. The measurements were compared with previously reported data from Caucasian subjects and Asian subjects. Statistical analysis was conducted by independent-samples t test through SPSS software. RESULTS: (1) Twenty two out of the 28 parameters were found significantly different between males and females. Most of the parameters in males were found larger than that in females (p < 0.05). (2) The difference was found larger in comparison with the Caucasian subject groups than that with Asian subject groups. (3) All the selected 11 parameters measured by CT images were found to be smaller than those by X-ray images (p < 0.05). CONCLUSION: The morphological parameters were found different between the Caucasian and Chinese northeast populations. Precise data of the ankle joint morphology were provided for the design and clinical application of TAA in the Chinese population.

Synthesis of multi-substituted allenes from organoalane reagents and propargyl esters by using a nickel catalyst.

A highly efficient and simple route for the synthesis of multi-substituted allenes has been developed by a nickel catalyzed SN2' substitution reaction of propargyl esters with organic aluminium reagents under mild conditions, which gave the corresponding multi-substituted allenes in good to excellent yields (up to 92%) and high selectivities (up to 99%) at 60 °C for 6 h in THF. Aryls bearing electron-donating or electron-withdrawing groups in propargyl esters gave products in good yields. In addition, the multi-substituted allenes bearing a thienyl or a pyridyl group were obtained in 95-97% selectivities with isolated yields of 72-83%. Furthermore, the SN2' substitution reaction worked efficiently with propargyl carbonate compounds as well. On the basis of the experimental results, a possible catalytic cycle has been proposed.

Recent advances on the role of long non-coding RNA H19 in regulating mammalian muscle growth and development.

As one of the first identified long non-coding RNAs (lncRNAs), H19 plays a wide range of roles in vivo, including not only as a tumor suppressor and oncogene involved in disease process, but also as a regulator of growth and development of multiple tissues in mammalian embryos. The function of H19 in muscles (both skeletal and cardiac muscle) draws widespread attention due to the following two reasons. On one hand, H19 promotes myogenic differentiation and myogenesis of skeletal muscle satellite cells (SMSCs) via regulating Igf2 in cis. On the other hand, H19 also modulates the target genes in trans, including sponging let-7, miR-106 or miR-29 to mediate myocyte glucose uptake, cardiomyocyte proliferation and tendon repair, as well as promote embryonic development and muscle regeneration through binding to MBD1 as a chromatin modifier. In this review, we summarize the role of H19 in mammalian muscles, which will provide a reference for further research to unveil the molecular mechanism of muscle growth and development.

Nickel-catalyzed substitution reactions of propargyl halides with organotitanium reagents.

A simple and mild catalytic coupling reaction of propargyl halides with organotitanium reagents is reported. The reaction of propargyl bromide with organo-titanium reagents mediated by NiCl2 (2 mol%) and PCy3 (4 mol%) in CH2Cl2 afforded coupling product allenes in good to excellent yields (up to 95%) at room temperature. However, NiCl2(PPh3)2 was the best catalyst for substituted propargyl halides to yield allenes or alkynes preferentially. On the basis of the experimental results, a possible catalytic cycle has been proposed.

Laparoscopic liver resection under hemihepatic vascular inflow occlusion using the lowering of hilar plate approach.

BACKGROUND: With advances in technology, laparoscopic liver resection is widely accepted. Laparoscopic liver resection under hemihepatic vascular inflow occlusion has advantages over the conventional total hepatic inflow occlusion using the Pringle's maneuver, especially in patients with cirrhosis. METHOD: From November 2011 to August 2012, eight consecutive patients underwent laparoscopic liver resection under hemihepatic vascular inflow occlusion using the lowering of hilar plate approach with biliary bougie assistance. RESULTS: The types of liver resection included right hepatectomy (n=1), right posterior sectionectomy (n=1), left hepatectomy and common bile duct exploration (n=1), segment 4b resection (n=1), left lateral sectionectomy (n=2), and wedge resection (n=2). Four patients underwent right and 4 left hemihepatic vascular inflow occlusion. Four patients had cirrhosis. The mean operation time was 176.3 minutes. The mean time taken to achieve hemihepatic vascular inflow occlusion was 24.3 minutes. The mean duration of vascular inflow occlusion was 54.5 minutes. The mean intraoperative blood loss was 361 mL. No patient required blood transfusion. Postoperatively, one patient developed bile leak which healed with conservative treatment. No postoperative liver failure and mortality occurred. The mean hospital stay of the patients was 7 days. CONCLUSION: Our technique of hemihepatic vascular inflow vascular occlusion using the lowering of hilar plate approach was safe, and it improved laparoscopic liver resection by minimizing blood loss during liver parenchymal transection.

Electrochemical desulfurative formation of C-N bonds through selective activation of inert C(sp3)-S bonds.

In this study, we introduce an efficient, metal-free electrocatalytic desulfurative protocol for forming C-N bonds by selectively activating inert C(sp3)-S bonds of alkyl thioethers. This method offers a straightforward and environmentally friendly approach for modification of heterocyclic compounds from readily accessible thioethers. Preliminary mechanistic investigations suggest that the reaction proceeds via a carbocation intermediate. Furthermore, successful synthesis on a 10-gram scale was achieved in a continuous flow electrochemical reactor.

Multiple enzyme-mimic polypeptide based carbon nanoparticles by ROP and Fe coordination for ROS regulation and photo-thermal therapy against bacterial infection.

Novel strategy is urgently needed to overcome the bacterial infection all over the world due to unreasonable use of biotics. In recent years, nanozymes have attracted great interests of researchers for their high catalytic efficiency and biocompatibility. In this study, a novel multiple enzyme-mimic polypeptide-based carbon nanoparticle was synthesized by N-carboxyanhydride mediated ring opening polymerization (ROP) and Fe coordination for actualizing ROS regulation and photo-thermal therapy. The multiple enzyme-mimic activities of the nanozyme, such as peroxidase, oxidase, catalase, and glutathione peroxidase, were detailly explored in ROS regulation for potential utilization in bacterial inhibition. The photo-thermal effect of the nanozyme was investigated under 808 nm NIR irradiation. Enhanced inhibition rate of the as prepared nanozyme was observed against Gram-negative Escherichia coli (99.03 %) and Gram positive Staphylococcus aureus (99.78 %) planktonic bacteria. Methicillin-resistant Staphylococcus aureus (MRSA) was chosen as the drug resistant bacteria model to evaluate the efficiency in bacterial biofilm disruption. Improved healing efficacy of 99.05 % against MRSA wound infection and excellent biosafety were observed in mice model experiments for the as prepared nanozyme. In conclusion, the as synthesized nanozyme with ROS regulation, enhanced bacteria inhibition, and excellent biocompatibility could be potentially applied in clinic against bacterial infection.

Poly-l-lysine modified MOF nanoparticles with pH/ROS sensitive CIP release and CUR triggered photodynamic therapy against drug-resistant bacterial infection.

The challenge of drug resistance in bacteria caused by the over use of biotics is increasing during the therapy process, which has attracted great attentions of the clinicians and scientists around the world. Recently, photodynamic therapy (PDT) triggered by photosensitizer (PS) has become a promising treatment method because of its high efficacy, easy operation, and low side effect. Herein, the poly-l-lysine (PLL) modified metal-organic framework (MOF) nanoparticles, ZIF/PLL-CIP/CUR, were synthesized to allow both reactive oxygen species (ROS) responsive drug release and photodynamic effect for synergistic therapy against drug resistant bacterial infections. The PLL was modified on the shell of the zeolite imidazole framework (ZIF) by the ROS-responsive thioketal linker for controllable CIP release. CUR were encapsulated in ZIF as the photosensitizer for blue light mediated photodynamic effect to produce singlet oxygen (1O2) and superoxide anion radical (O2-) for efficient inhibition towards methicillin-resistant Staphylococcus aureus (MRSA). The charge conversion from negative charge (-4.6 mV) to positive charge (2.6 mV) was observed at pH 7.4 and pH 5.5, and 70.9 % CIP was found released at pH 5.5 in the presence of H2O2, which suggests the good biosafety at physiological pH and ROS-responsive drug release of the as-prepared nanoparticle in the bacterial microenvironment. The as-prepared nanoparticles could effectively kill MRSA and disrupt bacterial biofilm by combination of chemo- and photodynamic therapy. In mice model, the as-prepared nanoparticles exhibited excellent biosafety and synergistic effect with 98.81 % healing rate in treatment of MRSA infection, which is considered as a promising candidate in combating drug resistant bacterial infection.

[Spatial and Temporal Evolution Characteristics of Carbon Emission from Land Use and Influencing Factors in Gansu Province].

Land ecosystems are the largest carbon sink in the world, and land use change is one of the main factors leading to regional carbon emissions. By studying the spatiotemporal evolution characteristics and influencing factors of land use carbon emissions in Gansu Province from 2000 to 2020, this research aimed to provide a scientific basis and reference for promoting low-carbon land use and low-carbon economic development in Gansu Province. Using land use data and the greenhouse gas emission coefficient method, the study analyzed the growth trend of land use carbon emissions at the city-regional scale in Gansu Province, and the spatiotemporal evolution characteristics at the provincial scale, and identified the controlling factors through principal component analysis. The results showed that： ① From 2000 to 2020, land use carbon emissions in Gansu Province showed an overall increasing trend, from 24.289 3 million tons to 57.739 6 million tons. The first stage from 2000 to 2014 was a significant increase period, whereas the second stage from 2014 to 2020 was a stable and slightly decreasing period. Construction land was the main carbon source, and the carbon intensity continued to increase. ② Spatially, there was an "east high, west low" pattern, with carbon emissions in the eastern part of the province significantly higher than those in the western part. ③ Based on emission characteristics, Gansu Province could be divided into five types of carbon emission zones： slow growth, relatively slow growth, moderate growth, relatively fast growth, and rapid growth. ④ The main reasons for the continuous increase in land use carbon emissions in Gansu Province were economic development level, degree of land use, and energy consumption.

Levels of circulating Th17 cells and regulatory T cells in ankylosing spondylitis patients with an inadequate response to anti-TNF-α therapy.

PURPOSE: To investigate the effects of TNF-α blockage on levels of circulating Th17, Treg and their related cytokines in ankylosing spondylitis (AS) patients with different response to anti-TNF-α therapy. METHODS: The frequencies of circulating Th17 and Treg and serum levels of related cytokines were determined using flow cytometry analysis and ELISA, respectively, in 222 AS patients both before (baseline) and 6 months after anti-TNF-α therapy. Therapeutic response was defined according to ASAS (Assessment in Spondyloarthritis International Society) response criteria. RESULTS: Significantly higher baseline circulating Th17 and serum TNF-α, IL-6, IL-17, IL-23 were observed in active AS patients than in healthy controls. After anti-TNF-α therapy, 168 patients (75.7 %) were responders and 54 (24.3 %) were non-responders. Frequencies of Th17 significantly decreased in responders, but significantly increased in non-responders. Treg increased significantly in responders but decreased significantly in non-responders. Levels of TNF-α, IL-6, IL-17, and IL-23 were significantly decreased in responders. In contrast, IL-17 and IL-23 significantly increased in non-responders. TGF-ß were significantly increased only in responders, whereas no significant changes were seen in IL-10 in either responders or non-responders. Spearman correlation analysis showed that frequencies of Th17 and levels of TNF-α, IL-6, IL-17, and IL-23 were positively correlated with BASDAI score. They were also positively correlated with BASFI score except for IL-6. Treg were found to be negatively correlated with BASDAI score. CONCLUSIONS: The beneficial effect of anti-TNF-α therapy in AS might not only neutralize the effects of TNF-α but also down-regulate Th17 and Th17-related cytokines accompanied by up-regulating the Treg/TGF-ß axis in responders.

Yields, phenolic profiles and antioxidant activities of Ziziphus jujube Mill. in response to different fertilization treatments.

Increasing demand for more jujube (Ziziphus jujube Mill.) production requires understanding the specific fertilization needs of jujube trees. This study was conducted to compare fruit yields, phenolic profiles and antioxidant activity of jujube in response to different fertilizers. Application of organic fertilizer appeared to enhance the phenolics and antioxidant activity accumulation of jujubes, compared to conventional fertilized jujubes. Amongst inorganic fertilizers, supplemental potassium as an individual nutrient improved the accumulation of phenolics in jujubes. Our results demonstrate that phenolics levels and antioxidant activity of jujube can be manipulated through fertilizer management and tracked by following proanthocyanidin concentrations. In a practical production context, the combination of organic fertilizers and inorganic fertilizers such as more supplemental individual potassium, and less supplemental individual nitrogen and phosphorus, might be the best management combination for achieving higher phenolic concentration, stronger antioxidant activity and a good harvest.

Metal-free photoinduced C(sp3)-H/C(sp3)-H cross-coupling to access α­tertiary amino acid derivatives.

The cross-dehydrogenative coupling (CDC) reaction is the most direct and efficient method for constructing α-tertiary amino acids (ATAAs), which avoids the pre-activation of C(sp3)-H substrates. However, the use of transition metals and harsh reaction conditions are still significant challenges for these reactions that urgently require solutions. This paper presents a mild, metal-free CDC reaction for the construction of ATAAs, which is compatible with various benzyl C-H substrates, functionalized C-H substrates, and alkyl substrates, with good regioselectivity. Notably, our method exhibits excellent functional group tolerance and late-stage applicability. According to mechanistic studies, the one-step synthesized and bench-stable N-alkoxyphtalimide generates a highly electrophilic trifluoro ethoxy radical that serves as a key intermediate in the reaction process and acts as a hydrogen atom transfer reagent. Therefore, our metal-free and additive-free method offers a promising strategy for the synthesis of ATAAs under mild conditions.

Magnetic ion-imprinted polyacrylonitrile-chitosan electro-spun nanofibrous membrane as recyclable adsorbent with selective heavy metal removal and antibacterial fouling in water treatment.

Water pollution has become one of the most concerned environmental issues on the worldwide scale. Due to the harmfulness of the heavy metal ions and microorganisms in wastewater, novel filtration membranes for water treatment are expected to simultaneously clear these pollutants. Herein, the electro-spun polyacrylonitrile (PAN) based magnetic ion-imprinted membrane (MIIM) were fabricated to achieve both selective removal of Pb(II) ions and excellent antibacterial efficiency. The competitive removal experiments showed that the MIIM displayed efficiently selective removal of Pb(II) (45.4 mg·g-1). Pseudo-second-order mode and Langmuir isotherm equation is well matched with the equilibrium adsorption. The MIIM showed sustained removal performance (~79.0 %) against Pb(II) ions after 7 adsorption-desorption cycles with negligible Fe ions loss of 7.3 %. Moreover, the MIIM exhibited excellent antibacterial properties that >90 % of E. coli and S. aureus were killed by the MIIM. In conclusion, the MIIM provides a novel technological platform for integration of multi-function with selective metal ions removal, excellent cycling reusability, and enhanced antibacterial fouling property, which can be potentially utilized as a promising adsorbent in actual treatment of polluted water.

Phase-change composite filled natural nanotubes in hydrogel promote wound healing under photothermally triggered drug release.

It is of great importance to treat a bacterial-infected wound by a smart dressing capable of delivering antibiotics in a smart manner without causing drug resistance. The construction of smart release nanocontainers responsive to near-infrared (NIR) laser irradiation in an on-demand and stepwise way is a promising strategy for avoiding the emergence of multidrug-resistant bacteria. Here, we develop a hydrogel composite made of alginate and nanotubes with an efficient NIR-triggered release of rifampicin and outstanding antibacterial ability. This composite hydrogel is prepared through co-encapsulating antibacterial drug (rifampicin), NIR-absorbing dye (indocyanine green), and phase-change materials (a eutectic mixture of fatty acids) into halloysite nanotubes, followed by incorporation into alginate hydrogels, allowing the in-situ gelation at room temperature and maintaining the integrity of drug-loaded nanotubes. Among them, the eutectic mixture with a melting point of 39 °C serves as the biocompatible phase-change material to facilitate the NIR-triggered drug release. The resultant phase-change material gated-nanotubes exhibit a prominent photothermal efficiency with multistep drug release under laser irradiation. In an in vitro assay, composite hydrogel provides good antibacterial potency against Staphylococcus aureus, one of the most prevalent microorganisms of dangerous gas gangrene. A bacterial-infected rat full-thickness wound model demonstrates that the NIR-responsive composite hydrogel inhibits the bacteria colonization and suppresses the inflammatory response caused by bacteria, promoting angiogenesis and collagen deposition to accelerate wound regeneration. The NIR-responsive composite hydrogel has a great potential as an antibacterial wound dressing functionalized with controlled multistep treatment of the infected sites.

[Curcumin targeting miR-155-5p/TP53INP1 axis induced oxidative stress to regulate salivary gland tumor cell proliferation and apoptosis].

PURPOSE: To investigate the mechanism of curcumin targeting miR-155-5p/TP53INP1 axis to induce oxidative stress to regulate salivary gland tumor cell proliferation and apoptosis. METHODS: A253 cells were cultured by adding curcumin and transfected with miR-155-5p mimic and/or pcDNA3.1-TP53INP1. Cell proliferation was detected by CCK-8 assay cell apoptosis was detected by flow cytometry, cell migration ability was detected by scratch test. The targeting relationship between miR-155-5p and TP53INP1 was verified by dual luciferase reporter assay. miR-155-5p, TP53INP1 mRNA expression was detected by qRT-PCR. Western blot was performed to detect expression of TP53INP1, Caspase8, Caspase3, Bcl-2, Bax protein; and ELISA was used to determine SOD, Gpx, and MDA content. Statistical analysis was performed using SPSS 22.0 software package. RESULTS: Dual luciferase reporter assay confirmed that TP53INP1 was a downstream target regulatory molecule of miR-155-5p. Compared with DMSO group, cell apoptosis, Caspase8, Caspase3, Bax protein expression and TP53INP1 expression were significantly increased in curcumin group, while Bcl-2 protein expression, miR-155-5p mRNA and number of cell migration were significantly decreased(P<0.05). Compared with curcumin + miR-155-5p mimic group, cell apoptosis, Caspase8, Caspase3, Bax protein expression was significantly increased in curcumin + pcDNA3.1-TP53INP1 group and curcumin + miR-155-5p mimic + pcDNA3.1-TP53INP1 group; Bcl-2 protein expression was significantly increased(P<0.05), SOD, GSH-PX activities and number of cell migration were significantly decreased and MDA content was significantly increased in curcumin+pcDNA3.1-TP53INP1 group (P<0.05). CONCLUSIONS: Curcumin inhibited A253 cell proliferation and promoted A253 cell apoptosis. The mechanism may be related to targeting miR-155-5p/TP53INP1 axis to induce oxidative stress regulation.

Cs2CO3 catalyzed direct aza-Michael addition of azoles to α,ß-unsaturated malonates.

A highly efficient method for the synthesis of azole derivatives via a direct aza-Michael addition of azoles to α,ß-unsaturated malonates using Cs2CO3 as a catalyst, has been successfully developed. A series of azole derivatives have been obtained in up to 94% yield and the reaction could be amplified to gram scale in excellent yield in the presence of 10 mol% of Cs2CO3.

Highly selective cross-coupling reactions of 1,1-dibromoethylenes with alkynylaluminums for the synthesis of aryl substituted conjugated enediynes and unsymmetrical 1,3-diynes.

A highly efficient method for the synthesis of aryl substituted conjugated enediynes and unsymmetrical 1,3-diynes via selective cross-coupling reactions of 1,1-dibromoethylenes with alkynylaluminums using the Pd(OAc)2-DPPE and Pd2(dba)3-TFP complexes as catalysts, respectively, has been successfully developed. Though the alkyl substituted conjugated enediynes and unsymmetrical 1,3-diynes were not obtained, this case is also remarkable as the same starting materials could selectively produce either aryl substituted conjugated enediynes or unsymmetrical 1,3-diynes in moderate to excellent yields (up to 99%) in the different Pd-phosphine catalytic systems.

Surface charge switchable nano-micelle for pH/redox-triggered and endosomal escape mediated co-delivery of doxorubicin and paclitaxel in treatment of lung adenocarcinoma.

Recently, the stimulus-sensitive drug co-delivery system has gained increasing attentions in the clinic and exhibits improved efficiency rather than the mono-chemotherapy in anti-tumor therapy. Herein, the smart charge switchable nano-micelles (NMs) were fabricated for the endosomal escape mediated co-delivery of doxorubicin (DOX) and paclitaxel (PTX) in treatment of lung adenocarcinoma. The disulfide bonds were facilitated as the linker of the polymer backbone to achieve the redox-sensitive degradation by high intracellular GSH, and acid-liable DMMA was grafted onto DOX molecules for pH-triggered drug release under acidic tumoral microenvironment. Folic acid (FA) was utilized as targeting molecule for facilitating entry of the as prepared NMs into cancer cells. Remarkably, the as fabricated NMs exhibited surface charge-switch from negative to positive during transmitting from physiological pH to the tumor extracellular pH, which can improve the cellular internalization towards cancer cell. Subsequently, the "proton-sponge" effect mediated endosome escape of the NMs was facilitated in the acidic endo/lysosome environment. By the cell assay, the NMs possessed good biocompatibility, excellent cellular uptake, and improved inhibition rate against cancer cell. Moreover, the co-delivery of DOX/PTX exhibited synergistic and enhanced solid tumor inhibition efficiency comparing to mono-chemotherapy in A-549 tumor bearing mice model. Based on above experimental results, the as prepared drug co-delivery system showed promising biosafety and potentials for efficient lung adenocarcinoma treatment in clinic.

Lycium barbarum Polysaccharides Promotes Mitochondrial Biogenesis and Energy Balance in a NAFLD Cell Model.

OBJECTIVE: To explore the protective effect and underlying mechanism of Lycium barbarum polysaccharides (LBP) in a non-alcoholic fatty liver disease (NAFLD) cell model. METHODS: Normal human hepatocyte LO2 cells were treated with 1 mmol/L free fatty acids (FFA) mixture for 24 h to induce NAFLD cell model. Cells were divided into 5 groups, including control, model, low-, medium- and high dose LBP (30,100 and 300 µg/mL) groups. The monosaccharide components of LBP were analyzed with high performance liquid chromatography. Effects of LBP on cell viability and intracellular lipid accumulation were assessed by cell counting Kit-8 assay and oil red O staining, respectively. Triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), adenosine triphosphate (ATP) and oxidative stress indicators were evaluated. Energy balance and mitochondrial biogenesis related mRNA and proteins were determined by quantitative real-time polymerase chain reaction and Western blot, respectively. RESULTS: Heteropolysaccharides with mannose and glucose are the main components of LBP. LBP treatment significantly decreased intracellular lipid accumulation as well as TG, ALT, AST and malondialdehyde levels (P<0.05 or P<0.01), increased the levels of superoxide dismutase, phospholipid hydroperoxide glutathione peroxidase, catalase, and ATP in NAFLD cell model (P<0.05). Meanwhile, the expression of uncoupling protein 2 was down-regulated and peroxisome proliferator-activated receptor gamma coactivator-1α/nuclear respiratory factor 1/mitochondrial transcription factor A pathway was up-regulated (P<0.05). CONCLUSION: LBP promotes mitochondrial biogenesis and improves energy balance in NAFLD cell model.

Dietary ß-carotene and vitamin A and risk of Parkinson disease: A protocol for systematic review and meta-analysis.

BACKGROUND: The beneficial effects of dietary ß-carotene and vitamin A on Parkinson disease (PD) have been confirmed, but some studies have yielded questionable results. Therefore, this meta-analysis investigated the effect of dietary ß-carotene and vitamin A on the risk of PD. METHODS: The following databases were searched for relevant paper: PubMed, Embase, Medline, Scopus, Cochrane Library, CNKI, Wanfang Med online, and Weipu databases for the relevant paper from 1990 to March 28, 2022. The studies included were as follows: ß-carotene and vitamin A intake was measured using scientifically recognized approaches, such as food frequency questionnaire (FFQ); evaluation of odds ratios using OR, RR, or HR; ß-carotene and vitamin A intake for three or more quantitative categories; and PD diagnosed by a neurologist or hospital records. RESULTS: This study included 11 studies (four cohort studies, six case-control studies, and one cross-sectional study). The high ß-carotene intake was associated with a significantly lower chance of developing PD than low ß-carotene intake (pooled OR = 0.83, 95%CI = 0.74-0.94). Whereas the risk of advancement of PD was not significantly distinctive among the highest and lowest vitamin A intake (pooled OR = 1.08, 95%CI = 0.91-1.29). CONCLUSIONS: Dietary ß-carotene intake may have a protective effect against PD, whereas dietary vitamin A does not appear to have the same effect. More relevant studies are needed to include into meta-analysis in the further, as the recall bias and selection bias in retrospective and cross-sectional studies cause misclassifications in the assessment of nutrient intake.