Low-sugar universal mRNA vaccine against coronavirus variants with deletion of glycosites in the S2 or stem of SARS-CoV-2 spike messenger RNA (mRNA).

Since the outbreak of Severe Acute Respiratory Syndrome Virus-2 (SARS-CoV-2) in 2019, more than 15 million spike protein sequences have been identified, raising a new challenge for the development of a broadly protective vaccine against the various emerging variants. We found that the virus, like most other human viruses, depends on host-made glycans to shield the conserved epitopes on spike protein from immune response and demonstrated that deletion of the glycan shields exposed highly conserved epitopes and elicited broadly protective immune responses. In this study, we identified 17 conserved epitopes from 14 million spike protein sequences and 11 of the conserved epitopes are in the S2 domain, including the six most conserved epitopes in the stem region. We also demonstrated that deletion of the glycosites in the spike messenger RNA (mRNA) S2 domain or the stem region exposed the highly conserved epitopes and elicited broadly protective immune responses, particularly CD-8+ T cell response against various SARS-CoV-2 variants, and other human coronaviruses including MERS, SARS viruses, and those causing common cold.

Safety and efficacy of radiotherapy combined with chemotherapy for recurrent metastatic renal pelvic and ureteral carcinoma.

PURPOSE: To retrospectively investigate the safety and efficacy of radiotherapy combined with chemotherapy for recurrent metastatic renal pelvic and ureteral carcinoma. METHODS: 109 patients were enrolled in this study, including 44 patients in the radiochemotherapy group and 65 patients in the chemotherapy group. Propensity score matching (PSM) was used to balance the baseline characteristics of the two groups by 1:1 matching. Kaplan-Meier method was used to calculate PFS and OS. Cox regression model was used for multivariate analysis. The side effects were evaluated by CTCAE v5.0 RESULTS: The median follow-up time was 14.5 months. Multivariate analysis showed that radiotherapy was a good independent prognostic factor for OS (HR: 0.327, 95% CI 0.157-0.680, P = 0.003). After matching, there were 40 patients in both groups, and the median PFS and OS in the radiochemotherapy group were longer than those in the chemotherapy group (PFS: 10.4 vs. 6.7 months, P = 0.035; OS: 43.5 vs. 18.8 months, P < 0.001). In addition, in the radiochemotherapy group, patients treated with radiotherapy before first-line chemotherapy failure had a longer PFS than those treated with radiotherapy after chemotherapy failure (median PFS: 15.7 vs. 6 months, P = 0.003). There was no significant difference in the incidence of grade 3-4 toxicities between the two groups (52.3% vs. 50.8%, P = 0.878). CONCLUSION: For patients with recurrent metastatic renal pelvic and ureteral carcinoma, radiotherapy combined with chemotherapy is well tolerable and expected to bring long-term survival benefits, and the benefits of early interventional radiotherapy may be more obvious.

Three stilbenes from pigeon pea with promising anti-methicillin-resistant Staphylococcus aureus biofilm formation activity.

Cajaninstilbene acid (CSA), longistylin A (LLA), and longistylin C (LLC) are three characteristic stilbenes isolated from pigeon pea. The objective of this study was to evaluate the antibacterial activity of these stilbenes against Staphylococcus aureus and even methicillin-resistant Staphylococcus aureus (MRSA) and test the possibility of inhibiting biofilm formation. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of these stilbenes were evaluated. And the results showed that LLA was most effective against tested strains with MIC and MBC values of 1.56 µg/mL followed by LLC with MIC and MBC values of 3.12 µg/mL and 6.25 µg/mL as well as CSA with MIC and MBC values of 6.25 µg/mL and 6.25-12.5 µg/mL. Through growth curve and cytotoxicity analysis, the concentrations of these stilbenes were determined to be set at their respective 1/4 MIC in the follow-up research. In an anti-biofilm formation assay, these stilbenes were found to be effectively inhibited bacterial proliferation, biofilm formation, and key gene expressions related to the adhesion and virulence of MRSA. It is the first time that the anti-S. aureus and MRSA activities of the three stilbenes have been systematically reported. Conclusively, these findings provide insight into the anti-MRSA mechanism of stilbenes from pigeon pea, indicating these compounds may be used as antimicrobial agents or additives for food with health functions, and contribute to the development as well as application of pigeon pea in food science.

Effectiveness of a socioecological model-guided, smart device-based, self-management-oriented lifestyle intervention in community residents: protocol for a cluster-randomized controlled trial.

BACKGROUND: Healthy lifestyles are crucial for preventing chronic diseases. Nonetheless, approximately 90% of Chinese community residents regularly engage in at least one unhealthy lifestyle. Mobile smart devices-based health interventions (mHealth) that incorporate theoretical frameworks regarding behavioral change in interaction with the environment may provide an appealing and cost-effective approach for promoting sustainable adaptations of healthier lifestyles. We designed a randomized controlled trial (RCT) to evaluate the effectiveness of a socioecological model-guided, smart device-based, and self-management-oriented lifestyles (3SLIFE) intervention, to promote healthy lifestyles among Chinese community residents. METHODS: This two-arm, parallel, cluster-RCT with a 6-month intervention and 6-month follow-up period foresees to randomize a total of 20 communities/villages from 4 townships in a 1:1 ratio to either intervention or control. Within these communities, a total of at least 256 community residents will be enrolled. The experimental group will receive a multi-level intervention based on the socioecological model supplemented with a multi-dimensional empowerment approach. The control group will receive information only. The primary outcome is the reduction of modifiable unhealthy lifestyles at six months, including smoking, excess alcohol consumption, physical inactivity, unbalanced diet, and overweight/obesity. A reduction by one unhealthy behavior measured with the Healthy Lifestyle Index Score (HLIS) will be considered favorable. Secondary outcomes include reduction of specific unhealthy lifestyles at 3 months, 9 months, and 12 months, and mental health outcomes such as depression measured with PHQ-9, social outcomes such as social support measured with the modified Multidimensional Scale of Perceived Social Support, clinical outcomes such as obesity, and biomedical outcomes such as the development of gut microbiota. Data will be analyzed with mixed effects generalized linear models with family and link function determined by outcome distribution and accounting for clustering of participants in communities. DISCUSSION: This study will provide evidence concerning the effect of a mHealth intervention that incorporates a behavioral change theoretical framework on cultivating and maintaining healthy lifestyles in community residents. The study will provide insights into research on and application of similar mHealth intervention strategies to promote healthy lifestyles in community populations and settings. TRIAL REGISTRATION NUMBER: ChiCTR2300070575. Date of registration: April 17, 2023. https://www.chictr.org.cn/index.aspx .

Tunable mode convertor based on fiber Bragg grating inscribed in graded-index nine-mode fiber.

A tunable mode convertor is experimentally demonstrated based on a fiber Bragg grating (FBG), which is fabricated in a graded-index nine-mode fiber by using a femtosecond laser. Nine linearly polarized (LP) modes were excited and the coupling efficiency of them can reach 90%. By adjusting the polarization controller, the ±1st-, ±2nd-, ±3rd-, and ±4th-order orbital angular momentum (OAM) modes were excited, which means the OAM tuning of 0-±1ℏ, 0-±2ℏ, 0-±3ℏ, and 0-±4ℏ were achieved. LP21/LP02, LP31/LP12, LP41/LP22/LP03 modes were successfully tuned at 1556.00 nm, 1555.10 nm, and 1554.25 nm by twisting the FBG, respectively. Moreover, combined with polarization and torsion control, the tuning between 0th- and -2nd-order OAM has been realized, which is converted from the tuning between LP02 and LP21. By using this method, the OAM tuning of ±1-±3ℏ and ±4-0-±2ℏ may be further realized theoretically.

Euryachincoside, a Novel Phenolic Glycoside with Anti-Hepatic Fibrosis Activity from Eurya chinensis.

Eurya chinensis has been recorded as a folk medicine traditionally used for treatment of a variety of symptoms. However, the phytochemical and pharmacological investigations of this plant are still scarce. A novel phenolic glycoside named Euryachincoside (ECS) was isolated by chromatographic separation from E. chinensis, and its chemical structure was identified by analysis of HRMS and NMR data. Its anti-hepatic fibrosis effects were evaluated in both HSC-T6 (rat hepatic stellate cells) and carbon tetrachloride (CCl4)-induced mice with Silybin (SLB) as the positive control. In an in vitro study, ECS showed little cytotoxicity and inhibited transforming growth factor-beta (TGF-ß)-induced Collagen I (Col1) along with alpha-smooth muscle actin (α-SMA) expressions in HSC-T6. An in vivo study suggested ECS significantly ameliorated hepatic injury, secretions of inflammatory cytokines, and collagen depositions. Moreover, ECS markedly mediated Smad2/3, nuclear factor kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways both in vitro and vivo. These present findings confirmed that ECS is a novel phenolic glycoside from E. chinensis with promising curative effects on hepatic fibrosis, and its mechanisms may include decreasing extracellular matrix accumulation, reducing inflammation and attenuating free radicals via Smad2/3, NF-κB and Nrf2 signaling pathways, which may shed light on the exploration of more effective phenolic glycoside-based anti-fibrotic agents.

Cadmium facilitates the formation of large lipid droplets via PLCß2-DAG-DGKε-PA signal pathway in Leydig cells.

Cadmium (Cd) exposure damages the reproductive system. Lipid droplets (LDs) play an important role in steroid-producing cells to provide raw material for steroid hormone. We have found that the LDs of Leydig cells exposed to Cd are bigger than those of normal cells, but the effects on steroidogenesis and its underlying mechanism remains unclear. Using Isobaric tag for relative and absolute quantitation (iTARQ) proteomics, phosphodiesterase beta-2 (PLCß2) was identified as the most significantly up-regulated protein in immature Leydig cells (ILCs) and adult Leydig cells (ALCs) derived from male rats exposed to maternal Cd. Consistent with high expression of PLCß2, the size of LDs was increased in Leydig cells exposed to Cd, accompanied by reduction in cholesterol and progesterone (P4) levels. However, the high PLCß2 did not result in high diacylglycerol (DAG) level, because Cd exposure up-regulated diacylglycerol kinases ε (DGKε) to promote the conversion from DAG to phosphatidic acid (PA). Exogenous PA, which was consistent with the intracellular PA concentration induced by Cd, facilitated the formation of large LDs in R2C cells, followed by reduced P4 level in the culture medium. When PLCß2 expression was knocked down, the increased DGKε caused by Cd was reversed, and then the PA level was decreased to normal. As results, large LDs returned to normal size, and the level of total cholesterol was improved to restore steroidogenesis. The accumulation of PA regulated by PLCß2-DAG-DGKε signal pathway is responsible for the formation of large LDs and insufficient steroid hormone synthesis in Leydig cells exposed to Cd. These data highlight that LD is an important target organelle for Cd-induced steroid hormone deficiency in males.

Two new withanolides from the whole plants of Physalis peruviana.

Two new withaphysalin-type withanolides (18-O-ethylwithaphysalin R and 5-O-ethylphysaminimin C, 1 and 2), along with twelve known withanolides (3-14), were purified and identified from Physalis peruviana L. The chemical structures of these new isolates were elucidated through analyzing spectroscopic and HRESIMS data. All the obtained metabolites were appraised for their potential antiproliferative activity against the human breast cancer cell line MCF-7. Compound 7 was discovered to exhibit potent activity with an IC50 value of 3.51 µM and compounds 2, 6 and 14 showed weak cytotoxic effect.

[Dosimetric Impact of Titanium Alloy Implant in Spinal IMRT Plan].

The purpose of this study is to establish and apply a correction method for titanium alloy implant in spinal IMRT plan, a corrected CT-density table was revised from normal CT-density table to include the density of titanium alloy implant. Dose distribution after and before correction were calculated and compared to evaluate the dose deviation. Plans were also copied to a spinal cancer simulation phantom. A titanium alloy fixation system for spine was implanted in this phantom. Plans were recalculated and compared with the measurement result. The result of this study shows that the max dose of spinal cord showed significant difference after correction, and the deviation between calculation results and measurement results was reduced after correction. The method for expanding the range CT-density table, which means that the density of titanium alloy was included, can reduce the error in calculation.

Identification of ZBTB9 as a potential therapeutic target against dysregulation of tumor cells proliferation and a novel biomarker in Liver Hepatocellular Carcinoma.

BACKGROUND: Zinc finger and bric-a-brac/tramtrack/broad (ZBTB) domain-containing proteins have been reported to be associated with many tumors' development. However, in tumor initiation and progression, the role of ZBTB9, one of the protein family, and its prognostic value were yet to be elucidated in Liver Hepatocellular Carcinoma (LIHC). METHODS: We used R software and online bioinformatics analysis tools such as GEPIA2, cBioPortal, TIMER2, Metascape, UALCAN, STRING, TISIDB, and COSMIC to investigate ZBTB9's characteristics and function in LIHC, including abnormal expression, carcinogenic role, related signaling pathways and prognostic value. Furthermore, cell experiments (such as formation, wound healing, and transwell assays) and analyses based on clinical samples (such as immunohistochemistry (IHC) and promoter methylation analysis) were conducted to verify pivotal conclusions. RESULTS: ZBTB9 was overexpressed in LIHC samples compared to adjacent normal tissues. Through the analysis of genomic alteration and promoter hypomethylation, the clinical value and etiology of abnormal expression of ZBTB9 were preliminarily exlpored. Subsequent evidence showed that it could result in tumor progression and poor prognosis via activating cell cycle, DNA repair, MYC, and KRAS-associated signaling pathways as well as rendering immune dysregulation. After the knockdown of ZBTB9, evidently inhibited capacities of tumor cells proliferation and migration were observed. These results together indicated that ZBTB9 could be a promising prognostic biomarker and had the potential value to offer novel therapeutic targets for LIHC treatment. CONCLUSIONS: ZBTB9 was identified as a novel biomarker to predict the prognosis and tumor progression in LIHC, and a promising therapeutic target to invert tumor development.

Femtosecond laser inscribed helical long period fiber grating for exciting orbital angular momentum.

A method employing femtosecond lasers to inscribe helical long period fiber grating (HLPFG) for exciting orbital angular momentum (OAM) of light is experimentally demonstrated. In this method, the refractive index modulation (RIM) of HLPFG is realized by three-dimensional translation of a fiber without rotation, indicating better stability, repeatability and flexibility. The coupling efficiency can be customized by varying the radius of the helical RIM, except laser energy. The characteristics of phase and polarization purity of the coupled modes in HLPFGs are studied. Results show that HLPFGs can directly excite OAM modes, the polarization state and helical phase of the mode can be adjusted independently, and the purity is the highest at resonant wavelength, over 91%.

Direct generation of orbital angular momentum in orthogonal fiber Bragg grating.

We experimentally demonstrated an all-fiber reflective orbital angular momentum (OAM) generator based on orthogonal fiber Bragg grating (OFBG). The OFBG is formed by using a femtosecond laser to prepare two fiber Bragg gratings with a certain spacing in orthogonal planes. The ±1st- and ±2nd-order OAM modes were directly excited in this OFBG, and the chirality of the OAM modes depends on the relative positions of the two FBGs. The mode coupling properties and effects of center-to-center distance on OAM modes were investigated as well.

Drug-induced liver injury following the use of tocilizumab or sarilumab in patients with coronavirus disease 2019.

BACKGROUNDS: Interleukin-6 (IL-6) blockers including tocilizumab and sarilumab were approved by the U.S. Food and Drug Administration (FDA) in June 2021 for the treatment of patients with moderate to severe COVID-19. The use of sarilumab or tocilizumab in COVID-19 patients has been related to a reduction in mortality compared to standard care. Recent evidence has emerged concerning drug-induced liver injury (DILI) after sarilumab or tocilizumab applications in COVID-19 patients. AIMS: The study aimed to estimate DILI associated with sarilumab or tocilizumab in treating moderate to severe patients infected with SARS-Cov-2. METHODS: We conducted a retrospective pharmacovigilance study by data mining of the FDA's adverse event reporting systems (FAERS) database from the first quarter of 2004 to the fourth quarter of 2021 in confirmed COVID-19 patients. We analyzed DILI cases associated with tocilizumab or sarilumab in treating COVID-19 patients from the FAERS during this period. Disproportionality analysis and Bayesian analysis of COVID-19 patients were utilized for case analysis, and we also next compared the onset time and fatality rates of DILI following tocilizumab or sarilumab. RESULTS: A total of 275 cases of TCZ or SAR-related DILI reports were extracted. A total of 192 AEs cases were related to tocilizumab (TCZ), and 83 were related to sarilumab (SAR). In patients treated with TCZ, most were < 75 years old (51.57%), with more male than female (46.35% vs. 13.02%). The correlation between IL-6 receptor antagonists and DILI was stronger in SAR (ROR = 12.94; 95%CI 9.6-17.44) than in TCZ (ROR = 1.33; 95%CI 1.14-1.55). The onset time of DILI was different between TCZ and SAR, and a significant difference was observed in TCZ than SAR (P < 0.0001). A significant difference was observed in the mortality rate of TCZ and SAR (P = 0.0009). DILI associated with COVID-19 patients treated with TCZ appeared to have earlier onset-time (1(0-46) day) VS. SAR (3.5(0-27) day). CONCLUSION: This study shows strict monitor ought to be paid for TCZ or SAR when used for COVID-19 patients with poor liver function.

Spectacle lenses with slightly aspherical lenslets for myopia control: clinical trial design and baseline data.

OBJECTIVES: Myopia is a major public health problem and it is essential to find safe and effective means to control its progression. The study design and baseline data are presented for a one-year prospective, double-masked, crossover, randomized clinical trial evaluating the efficacy of single vision spectacle lenses with concentric rings of slightly aspherical contiguous lenslets technology (SAL) on myopia control. METHODS: One hundred 8- to 13-year old Chinese children with a refractive error of -0.75 D to -4.75 D were assigned to two groups. In Group 1, SAL and single vision lenses were each worn for 6 months, and Group 2 wore the lenses in the reversed order. Primary outcomes are axial length and spherical equivalent of cycloplegic refractive error. Secondary outcomes included corneal thickness, anterior chamber depth, lens thickness, visual acuity, and lens adaptation. RESULTS: No significant differences in baseline parameters (cycloplegic spherical equivalent, axial length, age) were found between groups (0.49 < p < 0.94). All children adapted well to the test lenses and there was no significant difference in visual acuity between the SAL and single vision lenses (p = 0.27). CONCLUSIONS: The children in the two well balanced groups had comparable visual acuity and adapted well to the test lenses. These results imply that visual acuity can be well improved by SAL lenses. Clear visual acuity provides the assurance for good compliance in this longitudinal study.

Obstacles to access to community care in urban senior-only households: a qualitative study.

BACKGROUND: The increased number of older adults living alone has created a substantial care need. However, the utilization rate of services and facilities to meet these needs are surprisingly low. Many of older adults experience difficulties accessing these services, although it remains unclear how these obstacles impede access to services. This study explored the obstacles and difficulties experienced by urban older adults in seeking community care. METHODS: A phenomenological study was carried out and participatory observation and in-depth interviews were employed to investigate the process of seeking care of older adults in urban communities. A total of 18 urban community-dwelling older adults aged 75 years and over were included. Data collected were analysed by content analysis. RESULTS: We identified the pathways by which senior-only households sought community care and encountered obstacles. (1) lack of community care information: older adults did not know where and how to get services, even though the care institutions scattered throughout the community; (2) limited mobility: older adults often suffered from various chronic diseases, which physically hindered their access to care resources; (3) complex process of achieving care: the functional fragmentation and geographical dispersion of care institutions made the care-seeking process challenging and confusing for older adults; (4) incomprehension of needs expression: limited interaction time and communication barriers between staff of institutions and the older adults were the final obstacle. Only by surmounting these obstacles one by one can older adults access the care resources effectively. CONCLUSIONS: When older adults in the community initiated calls for help, they encountered several obstacles. Their physiological and social disadvantages limited their ability to seek care physically. Lack of integration and clear guidance in the process of providing community care exacerbated these difficulties. Reform of care services should focus on the visibility and accessibility of services for older adults.

K-Means Clustering and Bidirectional Long- and Short-Term Neural Networks for Predicting Performance Degradation Trends of Built-In Relays in Meters.

The built-in relay in a meter is a key control component of a smart meter, and its reliability determines whether the user can use electricity safely and smoothly. In this paper, the degradation characteristics of the arc-burning energy are enhanced by the method of K-means clustering to replace degradation data, such as the overtravel time, release time, and other data. In existing methods, the meter needs to be disassembled to describe the degradation trend of the meter relay. The proposed method is combined with a bidirectional long short-term memory (Bi-LSTM) neural network to predict the degradation trend of the relay's performance. In this paper, K-means clustering is used to enhance the extraction of arc energy data features, and then the arc energy data obtained from the reliability lifetime test is assessed to predict the degradation trend of the meter relay by means of a bidirectional LSTM.

Orbital Angular Momentum Mode Sensing Technology Based on Intensity Interrogation.

A novel optical fiber sensing technology based on intensity distribution change in orbital angular momentum (OAM) mode is proposed and implemented herein. The technology utilizes a chiral long-period fiber grating (CLPFG) to directly excite the 1st-order OAM (OAM1) mode. The intensity changes in the coherent superposition state between the fundamental mode and the OAM1 mode at the non-resonant wavelength of the CLPFG is tracked in order to sense the external parameters applied to the grating area. Applying this technology to temperature measurement, the intensity distribution change has a good linear relationship with respect to temperature in the range of 30 °C to 100 °C. When the intensity was denoted by the number of pixels with a gray value of one after binarization of collected images, the sensitivity was 103 px/°C and the corresponding resolution was 0.0097 °C. Meanwhile, theoretical and experimental results show that the sensitivity and resolution can be further improved via changing the area of the collected image. Compared with sensing methods based on spiral interference pattern rotation in previous work, this sensing technology has the advantage of exquisite structure, easy realization, and good stability, thus making it a potential application in practices.

Design, Synthesis and Antifungal Evaluation of Novel Pyrylium Salt In Vitro and In Vivo.

Nowadays, discovering new skeleton antifungal drugs is the direct way to address clinical fungal infections. Pyrylium salt SM21 was screened from a library containing 50,240 small molecules. Several studies about the antifungal activity and mechanism of SM21 have been reported, but the structure-activity relationship of pyrylium salts was not clear. To explore the chemical space of antifungal pyrylium salt SM21, a series of pyrylium salt derivatives were designed and synthesized. Their antifungal activity and structure-activity relationships (SAR) were investigated. Compared with SM21, most of the synthesized compounds exhibited equivalent or improved antifungal activities against Candida albicans in vitro. The synthesized compounds, such as XY10, XY13, XY14, XY16 and XY17 exhibited comparable antifungal activities against C. albicans with MIC values ranging from 0.47 to 1.0 µM. Fortunately, a compound numbered XY12 showed stronger antifungal activities and lower cytotoxicity was obtained. The MIC of compound XY12 against C. albicans was 0.24 µM, and the cytotoxicity decreased 20-fold as compared to SM21. In addition, XY12 was effective against fluconazole-resistant C. albicans and other pathogenic Candida species. More importantly, XY12 could significantly increase the survival rate of mice with a systemic C. albicans infection, which suggested the good antifungal activities of XY12 in vitro and in vivo. Our results indicated that structural modification of pyrylium salts could lead to the discovery of new antifungal drugs.

Synthesis of Single-Layer Two-Dimensional Metal-Organic Frameworks M3 (HAT)2 (M=Ni, Fe, Co, HAT=1,4,5,8,9,12-hexaazatriphenylene) Using an On-Surface Reaction.

1,4,5,8,9,12-Hexaazatriphenylene (HAT) is one of the smallest polyheterocyclic aromatic building blocks for forming conjugated metal-organic frameworks (cMOFs). However, the strong inter-molecular steric hindrance impedes the growth of HAT-based cMOFs. Here we employ on-surface synthesis to grow single-layer two-dimensional cMOFs of M3 (HAT)2 (M=Ni, Fe, Co). Using scanning tunnelling microscopy and density-functional theory (DFT) analysis, we resolve that the frameworks comprise a hexagonal lattice of HAT molecules and a Kagome lattice of metal atoms. The DFT analysis indicates that Ni, Co and Fe carry a magnetic moment of 1.1, 2.5, and 3.7 µB, respectively. We anticipate that the small π-conjugated core of HAT and strong bidentate chelating coordination give rise to appealing electronic and magnetic properties.

Ultra-dense perfect optical orbital angular momentum multiplexed holography.

Optical orbital angular momentum (OAM) has been recently implemented in holography technologies as an independent degree of freedom for boosting information capacity. However, the holography capacity and fidelity suffer from the limited space-bandwidth product (SBP) and the channel crosstalk, albeit the OAM mode set exploited as multiplexing channels is theoretically unbounded. Here, we propose the ultra-dense perfect OAM holography, in which the OAM modes are discriminated both radially and angularly. As such, the perfect OAM mode set constructs the two-dimensional spatial division multiplexed holography (conventional OAM holography is 1D). The extending degree of freedom enhances the holography capacity and fidelity. We have demonstrated an ultra-fine fractional OAM holography with the topological charge resolution of 0.01. A 20-digit OAM-encoded holography encryption has also been exhibited. It harnesses only five angular OAM topological charges ranging from -16 to +16. The SBP efficiency is about 20 times larger than the conventional phase-only OAM holography. This work paves the way to compact, high-security and high-capacity holography.