Genome-scale exon perturbation screens uncover exons critical for cell fitness.

CRISPR-Cas technology has transformed functional genomics, yet understanding of how individual exons differentially shape cellular phenotypes remains limited. Here, we optimized and conducted massively parallel exon deletion and splice-site mutation screens in human cell lines to identify exons that regulate cellular fitness. Fitness-promoting exons are prevalent in essential and highly expressed genes and commonly overlap with protein domains and interaction interfaces. Conversely, fitness-suppressing exons are enriched in nonessential genes, exhibiting lower inclusion levels, and overlap with intrinsically disordered regions and disease-associated mutations. In-depth mechanistic investigation of the screen-hit TAF5 alternative exon-8 revealed that its inclusion is required for assembly of the TFIID general transcription initiation complex, thereby regulating global gene expression output. Collectively, our orthogonal exon perturbation screens established a comprehensive repository of phenotypically important exons and uncovered regulatory mechanisms governing cellular fitness and gene expression.

Cell type-specific role of CBX2 and its disordered region in spermatogenesis.

Polycomb group (PcG) proteins maintain the repressed state of lineage-inappropriate genes and are therefore essential for embryonic development and adult tissue homeostasis. One critical function of PcG complexes is modulating chromatin structure. Canonical Polycomb repressive complex 1 (cPRC1), particularly its component CBX2, can compact chromatin and phase-separate in vitro. These activities are hypothesized to be critical for forming a repressed physical environment in cells. While much has been learned by studying these PcG activities in cell culture models, it is largely unexplored how cPRC1 regulates adult stem cells and their subsequent differentiation in living animals. Here, we show in vivo evidence of a critical nonenzymatic repressive function of cPRC1 component CBX2 in the male germline. CBX2 is up-regulated as spermatogonial stem cells differentiate and is required to repress genes that were active in stem cells. CBX2 forms condensates (similar to previously described Polycomb bodies) that colocalize with target genes bound by CBX2 in differentiating spermatogonia. Single-cell analyses of mosaic Cbx2 mutant testes show that CBX2 is specifically required to produce differentiating A1 spermatogonia. Furthermore, the region of CBX2 responsible for compaction and phase separation is needed for the long-term maintenance of male germ cells in the animal. These results emphasize that the regulation of chromatin structure by CBX2 at a specific stage of spermatogenesis is critical, which distinguishes this from a mechanism that is reliant on histone modification.

An integrated space-to-ground quantum communication network over 4,600 kilometres.

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

The Integrator complex cleaves nascent mRNAs to attenuate transcription.

Cellular homeostasis requires transcriptional outputs to be coordinated, and many events post-transcription initiation can dictate the levels and functions of mature transcripts. To systematically identify regulators of inducible gene expression, we performed high-throughput RNAi screening of the Drosophila Metallothionein A (MtnA) promoter. This revealed that the Integrator complex, which has a well-established role in 3' end processing of small nuclear RNAs (snRNAs), attenuates MtnA transcription during copper stress. Integrator complex subunit 11 (IntS11) endonucleolytically cleaves MtnA transcripts, resulting in premature transcription termination and degradation of the nascent RNAs by the RNA exosome, a complex also identified in the screen. Using RNA-seq, we then identified >400 additional Drosophila protein-coding genes whose expression increases upon Integrator depletion. We focused on a subset of these genes and confirmed that Integrator is bound to their 5' ends and negatively regulates their transcription via IntS11 endonuclease activity. Many noncatalytic Integrator subunits, which are largely dispensable for snRNA processing, also have regulatory roles at these protein-coding genes, possibly by controlling Integrator recruitment or RNA polymerase II dynamics. Altogether, our results suggest that attenuation via Integrator cleavage limits production of many full-length mRNAs, allowing precise control of transcription outputs.

Comparative Effectiveness of Dupilumab and Omalizumab on Asthma Exacerbations and Systemic Corticosteroid Prescriptions: Real-World US ADVANTAGE Study.

BACKGROUND: In the US, dupilumab is approved for moderate-to-severe eosinophilic or oral corticosteroid-dependent asthma, while omalizumab is approved for managing moderate-to-severe allergic asthma uncontrolled by inhaled corticosteroids. However, limited comparative effectiveness data exist for these biologics due to differing patient characteristics and treatment histories. OBJECTIVE: This analysis assessed the real-world effectiveness of dupilumab and omalizumab for asthma among patients in the US. METHODS: In this retrospective observational study, TriNetX Dataworks electronic medical record data were used to identify asthma patients (age: ≥12 years) who initiated (index) dupilumab or omalizumab between November 2018 and September 2020, and who had at least 12 months of pre- and post-index clinical information. Inverse probability of treatment weighting (IPTW) was applied to balance potential confounding in treatment groups. Asthma exacerbation rates and systemic corticosteroid (SCS) prescriptions were compared using a doubly robust negative binomial regression model, adjusting for baseline exacerbation/SCS rates and patient characteristics with ≥10% standardized differences after IPTW. RESULTS: Overall, 2,138 patients in dupilumab and 1,313 in omalizumab treatment groups met all inclusion and exclusion criteria. After weighting, the majority of baseline characteristics were balanced (standard difference <10%) between the two groups. Dupilumab was associated with a 44% lower asthma exacerbation rate (p<0.0001) than omalizumab. Additionally, dupilumab treatment significantly (p<0.05) reduced SCS prescriptions by 28% during the follow-up period compared to omalizumab treatment. CONCLUSION: The US ADVANTAGE real-world study demonstrated a significant reduction in severe asthma exacerbations and SCS prescriptions for patients prescribed dupilumab compared to those prescribed omalizumab during 12 months of follow-up.

Real-world effectiveness of dupilumab in patients with asthma: Findings from the US ADVANTAGE study.

BACKGROUND: Dupilumab is approved as an add-on maintenance therapy for patients (≥6 years) with moderate-to-severe asthma. Better understanding of real-world effectiveness is needed. OBJECTIVE: To characterize the real-world effectiveness of dupilumab in asthma management. METHODS: This retrospective study included patients (≥12 years of age) diagnosed with asthma, initiating dupilumab between November 2018 and September 2020. The study used a US electronic medical record database (TriNetX Dataworks, Cambridge, Massachusetts). Asthma exacerbation rates before and after the initiation of dupilumab were analyzed using generalized estimating equations models with Poisson probabilistic link to estimate incidence rate ratios (IRRs). Sensitivity analyses were conducted based on previous exacerbation data, eosinophil levels, history of atopic dermatitis or chronic rhinosinusitis with nasal polyps, previous use of biologics, and presence of SARS-CoV-2 (COVID-19). RESULTS: A total of 2400 patients initiating dupilumab met all study criteria. After initiation of dupilumab, risk of asthma exacerbation was reduced by 44% (IRR, 0.56; 95% CI, 0.47-0.57; P = <0.0001) and systemic corticosteroid prescriptions by 48% (IRR, 0.52; 95% CI, 0.48, 0.56; P = <0.0001) compared with those before initiation of dupilumab. Adjustment for COVID-19 showed a greater reduction in asthma exacerbations (IRR, 0.50; 95% CI, 0.45-0.55; P = <0.0001). CONCLUSION: Current real-world efficacy evidence indicates that dupilumab reduces asthma exacerbations and total systemic corticosteroid prescriptions in clinical practice. The effectiveness of dupilumab was observed independent of exacerbation history, eosinophil levels, or COVID-19 impact.

[Research progress in treatment of chronic prostatitis/chronic pelvic pain syndrome with traditional Chinese medicine].

Chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS) is a common urological disease with complex etiology. The treatment effect of western medicine is not satisfactory, and the course of the disease is protracted, which brings great trouble to patients. Traditional Chinese medicine(TCM) has a variety of treatment methods based on syndrome differentiation and treatment, including internal treatment with TCM, acupuncture and massage, and other external treatment methods for comprehensive treatment, with significant effect. This study summarized the etiology and pathogenesis of CP/CPPS and found that western medicine cannot fully explain the etiology and pathogenesis of CP/CPPS. It was believed that CP/CPPS was mainly related to many factors such as special pathogen infection, voiding dysfunction, mental and psychological abnormalities, neuroendocrine abnormalities, immune abnormalities, excessive oxidative stress, pelvic diseases, and heredity. TCM believed that CP/CPPS was caused by damp heat, blood stasis, Qi stagnation, and poisoning and was closely related to the organs of the liver, spleen, kidney, lung, stomach, bladder, and meridians of Chong and Ren channels and three yin channels of the foot. In the treatment of TCM, multiple comprehensive treatment plans are currently used, including internal treatment with TCM(decoction, proprietary Chinese medicine, and unique therapies of famous doctors), acupuncture and massage treatment, and other external treatment methods(rectal administration, topical application of TCM, and ear acupoint pressure). Comprehensive regulation has significant clinical efficacy and prominent characteristics of TCM, and it is worth clinical promotion. This study aims to provide a reference for clinical prevention and treatment of CP/CPPS and points out potential directions for future research in this field.

Field test of quantum key distribution over aerial fiber based on simple and stable modulation.

We have developed a simple time-bin phase encoding quantum key distribution system, using the optical injection locking technique. This setup incorporates both the merits of simplicity and stability in encoding, and immunity to channel disturbance. We have demonstrated the field implementation of quantum key distribution over long-distance deployed aerial fiber automatically. During the 70-day field test, we achieved approximately a 1.0 kbps secure key rate with stable performance. Our work takes an important step toward widespread implementation of QKD systems in diverse and complex real-life scenarios.

Time-bin phase-encoding quantum key distribution using Sagnac-based optics and compatible electronics.

In this work, we present a new time-bin phase-encoding quantum key distribution (QKD), where the transmitter utilizes an inherently stable Sagnac-type interferometer, and has comparable electrical requirements to existing polarization or phase encoding schemes. This approach does not require intensity calibration and is insensitive to environmental disturbances, making it both flexible and high-performing. We conducted experiments with a compact QKD system to demonstrate the stability and secure key rate performance of the presented scheme. The results show a typical secure key rate of 6.2 kbps@20 dB and 0.4 kbps@30 dB with channel loss emulated by variable optical attenuators. A continuous test of 120-km fiber spool shows a stable quantum bit error rate of the time-bin basis within 0.4%∼0.6% over a consecutive 9-day period without any adjustment. This intrinsically stable and compatible scheme of time-bin phase encoding is extensively applicable in various QKD experiments, including BB84 and measurement-device-independent QKD.

Symptom control in patients with asthma using inhaled corticosteroids/long-acting ß2-agonists (fluticasone furoate/vilanterol or budesonide/formoterol) in the US: a retrospective matched cohort study.

OBJECTIVE: Treatment with fluticasone furoate/vilanterol (FF/VI), an inhaled corticosteroid/long-acting ß2-agonist therapy, reduces the risk of severe asthma exacerbations and improves lung function and symptom control in patients with asthma. However, real-world data remain limited among asthma patients in the United States (US). METHODS: This retrospective cohort study propensity score (PS) matched adult asthma patients initiating once-daily FF/VI 100/25 mcg with patients initiating twice-daily budesonide/formoterol (B/F) 160/4.5 mcg using a US claims database (January 1, 2015-December 31, 2018). Asthma control was measured by the mean number of short-acting ß2-agonist (SABA) canisters dispensed per patient-year (PPY) during follow-up. Time to first, and rates of, overall and severe asthma exacerbations were also measured. RESULTS: After PS matching, 18,531 patients receiving FF/VI were matched to 18,531 patients receiving B/F. Mean SABA canisters dispensed PPY was significantly lower for FF/VI users compared with B/F users (FF/VI: 1.47, B/F: 1.64; p < 0.001). FF/VI use resulted in 13% significantly lower risk of having an overall asthma-related exacerbation and 22% lower risk of a severe exacerbation versus B/F use (overall exacerbation hazard ratio [HR] [95% confidence interval (CI)]: 0.87 [0.82-0.92], p < 0.001; severe exacerbation HR [95% CI]: 0.78 [0.63-0.97], p = 0.027). Asthma-related exacerbation rates per 100 patient-days were also significantly lower for the FF/VI group compared with the B/F group (overall: 0.0475 vs. 0.0558, p < 0.001; severe: 0.0026 vs. 0.0033, p = 0.020). CONCLUSIONS: In real-world practice, initiation of once-daily FF/VI 100/25 mcg in adults with asthma was associated with lower use of SABA and fewer asthma-related exacerbations, which may indicate better asthma control, when compared with use of twice-daily B/F 160/4.5 mcg.

The acute effects of azithromycin use on cardiovascular mortality as compared with amoxicillin-clavulanate in US Veterans.

PURPOSE: Azithromycin is a common first-line antibiotic for respiratory infection; however, there is conflicting evidence regarding risk of cardiovascular death. We assessed cardiovascular and noncardiovascular mortality associated with azithromycin versus amoxicillin-clavulanate among US Veterans treated for nonear-nose-throat respiratory infection ("respiratory") or ear-nose-throat infection indication. METHODS: Electronic health record data from the US Veterans Health Administration database were used to identify Veterans (30-74 years) with outpatient dispensings of oral azithromycin versus amoxicillin-clavulanate for respiratory or ear-nose-throat infection (January 01, 2000-December 31, 2014). Outcomes assessed were risk of cardiovascular death and noncardiovascular death within 1-5 and 6-10 days postdispensing. Inverse probability of treatment-weighted proportional hazards models and binomial regression models were used to estimate hazard ratios (HRs) and compute risk differences (RD) per million courses of therapy. Cardiac death (subset of cardiovascular death) was assessed in sensitivity analyses. RESULTS: There were 629 345 azithromycin and 168 429 amoxicillin-clavulanate dispensings for respiratory indications, 143 783 azithromycin, and 203 142 amoxicillin-clavulanate dispensings for ear-nose-throat indications. For respiratory indications, azithromycin was not associated with a significantly different risk of cardiovascular death versus amoxicillin-clavulanate within 1-5 days postdispensing (HR [95% confidence interval (CI)]: 1.12 [0.63, 2.00]; RD [95% CI]: 11 [-43, 64] deaths/million courses of therapy). No elevated risk for azithromycin was found for ear-nose-throat indications. Pooled results for both indications via meta-analysis showed no association between antibiotics and cardiovascular mortality. There was no significant difference in risk of noncardiovascular or cardiac death between antibiotics postdispensing. CONCLUSION: Azithromycin was not associated with elevated risk of cardiovascular or noncardiovascular death versus amoxicillin-clavulanate among US Veterans.

Clinical and humanistic burden among pediatric patients with neurofibromatosis type 1 and plexiform neurofibroma in the USA.

PURPOSE: To assess clinical and humanistic burden among pediatric patients with neurofibromatosis type 1 (NF1) and plexiform neurofibroma (PN) in the USA. METHODS: NF1-PN patients aged 8-18 years (treatment-naïve or ≤ 1 month of selumetinib treatment) and their caregivers and caregivers of similar patients aged 2-7 years were recruited through the Children's Tumor Foundation to participate in an online cross-sectional survey (December 2020-January 2021). Caregivers provided data on patients' demographic and clinical characteristics and burden of debulking surgeries. Patients and caregivers provided self-reported or proxy responses to health-related quality of life (HRQoL) questions using validated instruments. RESULTS: Sixty-one patients and 82 caregivers responded to the survey. Median (range) age of patients was 11.5 (3-18) years, and 53.7% were female. Most were treatment-naïve (97.6%), with NF1-PN diagnosis for > 5 years (68.3%). Most patients (59.8%) had > 1 PN and 11.0% reporting > 5 PNs. Common NF1-PN symptoms included pain (64.6%), disfigurement (32.9%), and motor dysfunction (28.0%). Patients and caregiver proxies reported low overall HRQoL and reduced physical, emotional, social, and school functioning. Patients also reported considerable pain severity, interference, daily activity impairments, and movement difficulty. Few patients had received complete resections of their tumors (12.2%). 39.0% reported ≥ 1 debulking surgery, among whom, 15.6% had complications, and debulking surgery-related hospitalizations were common (53.1%). CONCLUSIONS: The clinical and humanistic burden among pediatric NF1-PN patients is substantial. While debulking surgeries are used for symptom management, they are associated with considerable clinical sequelae. Results highlight a need for improved disease management strategies.

Real-world outcomes of patients with locally advanced or metastatic epithelioid sarcoma.

BACKGROUND: Limited data are available on the real-world effectiveness and safety of systemic therapies for advanced (surgically unresectable and/or metastatic) epithelioid sarcoma (ES). METHODS: A retrospective medical records review was conducted in patients with advanced ES who were initiating first-line or ≥2 lines of systemic therapy (2000-2017) at 5 US cancer centers. The real-world overall response rate (rwORR), the duration of response (rwDOR), the disease control rate (rwDCR) (defined as stable disease for ≥32 weeks or any duration of response), and progression-free survival (rwPFS) were assessed by radiology reports. Overall survival (OS), rwDOR, and rwPFS were estimated from the time therapy was initiated using the Kaplan-Meier method. Serious adverse events were assessed. RESULTS: Of 74 patients (median age at diagnosis, 33 years; range, 10.6-76.3 years), 72% were male, and 85% had metastatic disease. The median number of lines of therapy was 2 (range, 1-7 lines of therapy), and 46 patients (62%) received ≥2 lines of systemic therapy. First-line regimens were usually anthracycline-based (54%) or gemcitabine-based (24%). For patients receiving first-line systemic therapy, the rwORR was 15%, the rwDCR was 20%, the median rwDOR was 3.3 months (95% CI, 2.1-5.2 months), the median rwPFS was 2.5 months (95% CI, 1.7, 6.9 months), and the median OS was 15.2 months (95% CI, 11.4-21.7 months). For those who received ≥2 lines of systemic therapy, the rwORR was 9%, the rwDCR was 20%, the median rwDOR was 4.5 months (95% CI, 0.7-5.6 months), and the median rwPFS was 6.0 months (95% CI, 3.2-7.4 months). Over one-half of patients (51.4%) experienced an adverse event, most frequently febrile neutropenia (14%), pain (10%), anemia, dyspnea, fever, thrombocytopenia, or transaminitis (5% each). CONCLUSIONS: Systemic therapies demonstrate limited efficacy in patients with advanced ES and have associated toxicities.

Real-World Characteristics, Treatment Patterns, Health Care Resource Use, and Costs of Patients with Diffuse Large B-Cell Lymphoma in the U.S.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) represents the most common subtype of non-Hodgkin lymphoma in the U.S., but current real-world data are limited. This study was conducted to describe real-world characteristics, treatment patterns, health care resource utilization (HRU), and health care costs of patients with treated DLBCL in the U.S. MATERIALS AND METHODS: A retrospective study was conducted using the Optum Clinformatics Data Mart database (January 2013 to March 2018). Patients with an International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis for DLBCL after October 2015 and no prior International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis for unspecified DLBCL or primary mediastinal large B-cell lymphoma were classified as incident; those with such codes were classified as prevalent. An adapted algorithm identified lines of therapy (e.g., first line [1L]). All-cause HRU and costs were calculated per-patient-per-year (PPPY) among patients with a ≥1L. RESULTS: Among 1,877 incident and 651 prevalent patients with ≥1L, median age was 72 years and 46% were female. Among incident patients, 22.6% had at least two lines (2L), whereas 38.4% of prevalent patients had ≥2L. The most frequent 1L therapy was rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Incident patients had 1.3 inpatient and 42.0 outpatient (OP) visits PPPY, whereas prevalent patients had 0.8 and 31.3 visits PPPY, respectively. Total costs were $137,156 and $81,669 PPPY for incident and prevalent patients, respectively. OP costs were the main driver of total costs at $88,202 PPPY, which were higher within the first year. CONCLUSION: This study showed that a large portion of patients require additional therapy after 1L treatment to manage DLBCL and highlighted the substantial economic burden of patients with DLBCL, particularly within the first year following diagnosis. IMPLICATIONS FOR PRACTICE: Patients diagnosed with diffuse large B-cell lymphoma (DLBCL) carry a substantial clinical and economic burden. A large portion of these patients require additional therapy beyond first-line treatment. There is significant unmet need among patients with DLBCL who require additional therapy beyond first-line treatment. Patients who do not respond to first-line therapy and are not eligible for transplants have very high health care resource utilization and costs, especially in the first 12 months following initiation of treatment.

Trifluridine/Tipiracil and Regorafenib in Patients with Metastatic Colorectal Cancer: A Retrospective Study at a Tertiary Oncology Center.

BACKGROUND: Trifluridine/tipiracil (FTD/TPI) and regorafenib prolong survival for patients with refractory metastatic colorectal cancer (mCRC); limited comparative effectiveness data exist. MATERIALS AND METHODS: A retrospective, longitudinal cohort study of patients with mCRC who initiated FTD/TPI or regorafenib (index therapy) between 2012 and 2017 at a U.S. tertiary oncology center, Dana-Farber Cancer Institute, was conducted. Using best tumor response assessments, real-world overall response rates (rwORR) and disease control rates (rwDCR) were described and analyzed using logistic regression. Survival rate was examined for each month after index therapy using Kaplan-Meier. Overall survival (OS) was assessed using Cox proportional hazards models. Subgroup analyses among patients with index therapy as second- or third-line were performed. RESULTS: One hundred twenty-six and 95 patients were treated with FTD/TPI or regorafenib as index therapy, respectively. Patients treated with FTD/TPI versus regorafenib had a better response (rwORR 52.5% vs. 34.2%; adjusted odds ratio [OR] = 2.6; all p value <.05; rwDCR 64.2% vs. 46.1%; adjusted OR = 2.5; all p value <.05). Similar findings were observed for FTD/TPI versus regorafenib as second- or third-line therapy (rwORR 54.8% vs. 25.9%; adjusted OR = 4.1; all p value <.05; rwDCR 69.0% vs. 37.0%; adjusted OR = 4.9; all p value <.05). A greater proportion of patients treated with FTD/TPI versus regorafenib survived at 3 months (86.2% vs. 73.4%; p value = .016) and 4 months (79.6% vs. 65.8%; p value = .017). Adjusted OS hazard ratio for FTD/TPI versus regorafenib was 0.80, p value = .157. CONCLUSION: Patients treated with FTD/TPI had better tumor response and disease control than patients treated with regorafenib. Subgroup analysis in second- or third-line suggests that early use of FTD/TPI may have clinical benefits. IMPLICATIONS FOR PRACTICE: In this retrospective cohort study, patients with refractory metastatic colorectal cancer treated with trifluridine/tipiracil (FTD/TPI) were significantly less likely than those treated with regorafenib to have dose modifications and more likely to have higher real-world objective response rate (rwORR) and real-world disease control rate (rwDCR) while treated. Patients treated with FTD/TPI versus regorafenib had significantly higher odds of having rwORR or rwDCR in adjusted analyses. Monthly survival rates were higher overall in patients treated with FTD/TPI versus regorafenib in the first 6 months of follow-up, particularly at months 3 and 4. This study offers insight into patients' treatment experience in real-world clinical settings.

Rabbit umbilical cord mesenchymal stem cells: A new option for tissue engineering.

BACKGROUND: The source and availability of cells for tissue engineering in large scale research or clinical trials requires special attention. We propose the idea of applying rabbit umbilical cord mesenchymal stem cells for this purpose. METHODS: Here, the structure of the rabbit umbilical cord was analyzed and compared to that of human umbilical cord, both macroscopically and histologically. Next, we isolated, cultured and identified the proliferative activity and immunological characteristics of rabbit umbilical cord mesenchymal stem cells in vitro using mixed lymphocyte reaction, flow cytometry and an enzyme-linked immunosorbent assay. Furthermore, we evaluated the effects of biphasic calcium phosphate ceramic scaffolds seeded with rabbit umbilical cord mesenchymal stem cells in rat cranial defect models using multiple techniques, including radiological, histological and immunohistochemistry. RESULTS: In vitro studies demonstated a high level of proliferation and multi-lineage differentiation potential in rabbit umbilical cord mesenchymal stem cells. Rabbit umbilical cord mesenchymal stem cells exibited low immunogenicity properties and immune suppression capability with respect to both the allogeneic and xenogeneic immune response. The results of the in vivo study showed that rabbit umbilical cord mesenchymal stem cells could promote osteogenesis in heterogeneous hosts. CONCLUSIONS: The rabbit umbilical cord mesenchymal stem cells may be a new source for tissue engineering.

Beneficial Effect of Consecutive Screening Mammography Examinations on Mortality from Breast Cancer: A Prospective Study.

Background Previously, the risk of death from breast cancer was analyzed for women participating versus those not participating in the last screening examination before breast cancer diagnosis. Consecutive attendance patterns may further refine estimates. Purpose To estimate the effect of participation in successive mammographic screening examinations on breast cancer mortality. Materials and Methods Participation data for Swedish women eligible for screening mammography in nine counties from 1992 to 2016 were linked with data from registries and regional cancer centers for breast cancer diagnosis, cause, and date of death (Uppsala University ethics committee registration number: 2017/147). Incidence-based breast cancer mortality was calculated by whether the women had participated in the most recent screening examination prior to diagnosis only (intermittent participants), the penultimate screening examination only (lapsed participants), both examinations (serial participants), or neither examination (serial nonparticipants). Rates were analyzed with Poisson regression. We also analyzed incidence of breast cancers proving fatal within 10 years. Results Data were available for a total average population of 549 091 women (average age, 58.9 years ± 6.7 [standard deviation]). The numbers of participants in the four groups were as follows: serial participants, 392 135; intermittent participants, 41 746; lapsed participants, 30 945; and serial nonparticipants, 84 265. Serial participants had a 49% lower risk of breast cancer mortality (relative risk [RR], 0.51; 95% CI: 0.48, 0.55; P < .001) and a 50% lower risk of death from breast cancer within 10 years of diagnosis (RR, 0.50; 95% CI: 0.46, 0.55; P < .001) than serial nonparticipants. Lapsed and intermittent participants had a smaller reduction. Serial participants had significantly lower risk of both outcomes than lapsed or intermittent participants. Analyses correcting for potential biases made little difference to the results. Conclusion Women participating in the last two breast cancer screening examinations prior to breast cancer diagnosis had the largest reduction in breast cancer death. Missing either one of the last two examinations conferred a significantly higher risk. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Stephen A. Feig in this issue.

Association of Ambient Fine Particulate Matter (PM2.5) with Elevated Fecal Hemoglobin Concentration and Colorectal Carcinogenesis: A Population-Based Retrospective Cohort Study.

The roles of ambient fine particulate matter (PM2.5) in the prevention of colorectal cancer (CRC) have been scarcely highlighted as there is short of empirical evidence regarding the influences of PM2.5 on multistep carcinogenic processes of CRC. A retrospective cohort design with multistate outcomes was envisaged by linking monthly average PM2.5 concentrations at 22 city/county level with large-scale cohorts of cancer-screened population to study the influences of PM2.5 on short-term inflammatory process and multistep carcinogenic processes of CRC. Our study included a nationwide CRC screening cohort of 4,628,995 aged 50-69 years who attended first screen between 2004 and 2009 and continued periodical screens until 2016. We aimed to illustrate the carcinogenesis of PM2.5 related to CRC by applying both hierarchical logistical and multistate Markov regression models to estimate the effects of air pollution on fecal immunochemical test (FIT) positive (a proxy of inflammatory marker) and pre-clinical and clinical states of CRC in the nationwide cohort. We found a significant association of high PM2.5 exposure and FIT-positive by an increased risk of 11% [95% confidence interval (CI), 10-12]. PM2.5 enhanced the risk of being preclinical state by 14% (95% CI, 10-18) and that of subsequent progression from pre-clinical to clinical state by 21% (95% CI, 14-28). Furthermore, the elevated risks for CRC carcinogenesis were significantly higher for people living in high PM2.5 pollution areas in terms of yearly averages and the number days above 35 µg/m3 than those living in low PM2.5 pollution areas. We concluded that both short-term and long-term PM2.5 exposure were associated with multistep progression of CRC, which were useful to design precision primary and secondary prevention strategies of CRC for people who are exposed to high PM2.5 pollution.

New progresses of circular RNA biology: from nuclear export to degradation.

Circular RNA, typically generated from backsplicing reaction, is a class of single-stranded and covalently linked RNA. Although most circular RNAs are lowly expressed, some of them are able to accumulate to high levels and even exceed their cognate mRNAs due to their longer half-lives. Once produced in the nucleus, the majority of circular RNAs are exported to the cytoplasm for their proper functions or degradation. In this review, we will summarize the biogenesis and classification of circular RNAs and highlight the recent advances in our understanding of circular RNA nuclear export and degradation.

Real-world impact of antiepileptic drug combinations with versus without perampanel on healthcare resource utilization in patients with epilepsy in the United States.

OBJECTIVES: Combination regimens of antiepileptic drugs (AEDs) with various mechanisms of action (MOA) are commonly used in patients with refractory epilepsy. However, outcomes related to combination AEDs with novel MOA, such as perampanel (PER), are not well described. This study compared healthcare resource utilization (HRU) among recipients of PER-based combinations versus recipients of other non-PER-based combinations. METHODS: This retrospective study used claims data from the Symphony Health's IDV® (Integrated Dataverse) database (August 2012 to July 2018). Patients were aged ≥12 years with epilepsy or non-febrile convulsions, were treated with AED combinations, and had ≥12 and ≥6 months pre- and post-index date, respectively (date of initiation of the second AED in the combination). AEDs were categorized based on MOA: selective non-competitive antagonist of AMPA receptors (i.e., PER), sodium channel blocker (SC), synaptic vesicle protein 2A binding (SV2), and gamma-aminobutyric acid analog (G). Patients were then classified into MOA-based cohorts: PER + SC, PER + SV2, PER + G, SC + SC, SC + SV2, SC + G, SV2 + G, and G + G. HRU outcomes were evaluated during follow-up and compared between PER-based cohorts and non-PER-based cohorts. RESULTS: On average, patients in the PER + SC (N = 3,592), PER + SV2 (N = 2,200), and PER + G (N = 1,313) cohorts were younger and had a lower Quan-Charlson comorbidity index than those in non-PER-based cohorts. PER + SC and PER + SV2 users had significantly fewer all-cause hospitalizations than non-PER-based users (adjusted RR range: 0.66-0.89, all P < 0.05), while PER + G recipients had fewer all-cause hospitalizations than recipients of SV2 + G and G + G (adjusted RR range: 0.92-0.94). Similar trends were observed for epilepsy-related hospitalizations. Across all comparisons, PER-based combinations were associated with significantly lower rates of all-cause clinic/office/outpatient visits relative to non-PER-based combinations (adjusted RR range: 0.69-0.86, all P < 0.05). SIGNIFICANCE: Results showed that patients treated with PER-based combinations had fewer all-cause and epilepsy-related hospitalizations, and fewer all-cause clinic/office/outpatient visits compared with patients treated with most other non-PER-based combinations.