MiRNA throughout heart growth along with renewal
Spliceosomal introns interrupt nuclear genes and are removed from RNA transcripts ("spliced") by machinery called spliceosomes. Although the vast majority of spliceosomal introns are removed by the so-called major (or "U2") spliceosome, diverse eukaryotes also contain a rare second form, the minor ("U12") spliceosome, and associated ("U12-type") introns.1-3 In all characterized species, U12-type introns are distinguished by several features, including being rare in the genome (∼0.5% of all introns),4-6 containing extended evolutionarily conserved splicing motifs,4,5,7,8 being generally ancient,9,10 and being inefficiently spliced.11-13 Here, we report a remarkable exception in the slime mold Physarum polycephalum. The P. polycephalum genome contains >20,000 U12-type introns-25 times more than any other species-enriched in a diversity of non-canonical splice boundaries as well as transformed splicing signals that appear to have co-evolved with the spliceosome due to massive gain of efficiently spliced U12-type introns. These results reveal an unappreciated dynamism of minor spliceosomal introns and spliceosomal introns in general.DNA-induced liquid-liquid phase separation of cyclic GMP-AMP synthase (cGAS) triggers a potent response to detect pathogen infection and promote innate immune signaling. Whether and how pathogens manipulate cGAS-DNA condensation to mediate immune evasion is unknown. We report the identification of a structurally related viral tegument protein family, represented by ORF52 and VP22 from gamma- and alpha-herpesvirinae, respectively, that employs a conserved mechanism to restrict cGAS-DNA phase separation. ORF52/VP22 proteins accumulate into, and effectively disrupt, the pre-formed cGAS-DNA condensation both in vitro and in cells. The inhibition process is dependent on DNA-induced liquid-liquid phase separation of the viral protein rather than a direct interaction with cGAS. Moreover, highly abundant ORF52 proteins carried within viral particles are able to target cGAS-DNA phase separation in early infection stage. Our results define ORF52/VP22-type tegument proteins as a family of inhibitors targeting cGAS-DNA phase separation and demonstrate a mechanism for how viruses overcome innate immunity.Rationale Our current understanding of tuberculosis pathophysiology is limited by a reliance on animal models, the paucity of human tuberculosis lung tissue, and traditional histopathological analysis, a destructive two-dimensional approach that provides limited spatial insight. Determining the three-dimensional (3D) structure of the necrotic granuloma, a characteristic feature of tuberculosis, will more accurately inform preventative TB strategies. Objectives To ascertain the 3D shape of the human tuberculous granuloma and its spatial relationship with airways and vasculature within large lung tissues. Methods We characterized the 3D microanatomic environment of human tuberculous lungs using micro-computed tomography (µCT), histopathology and immunohistochemistry. Using 3D segmentation software, we accurately reconstructed TB granulomas, vasculature, and airways in 3D and confirmed our findings using histopathology and immunohistochemistry. Measurements and main results We observed marked heterogeneity in the morphology, volume, and number of TB granulomas in human lung sections. Unlike depictions of granulomas as simple spherical structures, human necrotic granulomas exhibit complex, cylindrical, branched morphologies which are connected to the airways and shaped by the bronchi. 3D imaging of human tuberculosis lung sections provides unanticipated insight into the spatial organization of tuberculosis granulomas in relation to airways and the vasculature. Conclusions Our findings highlight the likelihood that a single structurally complex lesion could be mistakenly viewed as multiple independent lesions when evaluated in 2D. Also, lack of vascularization within obstructed bronchi establishes a paradigm for antimycobacterial drug tolerance. Lastly, our results suggest that bronchogenic spread of Mycobacterium tuberculosis re-seeds the lung.
Recent imaging studies demonstrate that the anterolateral ligament (ALL) is frequently injured at the time of anterior cruciate ligament (ACL) rupture. The intrinsic healing potential of these injuries after ACL reconstruction (ACLR) has not been defined.
The primary objective was to evaluate the rate and duration of the healing process of injured ALLs after ACLR using serial 3-dimensional magnetic resonance imaging (3D-MRI). The secondary objective was to investigate whether any patient, injury, or surgical factors influenced the healing rate. The hypothesis was that serial imaging would demonstrate that the ALL has limited healing potential.
Case series; Level of evidence, 4.
Patients enrolled in the study underwent 3D-MRI (slice thickness 0.5 mm) preoperatively and at 1, 6, 12, and 24 months after ACLR. BB-2516 nmr Three observers determined the grade of ALL injury according to the Muramatsu classification. Inter- and intraobserver reliabilities were calculated. The rates of injury and time points for healing ictive of an increased risk of nonhealing.
ALL injuries occurred in the majority of ACL-injured knees. They had limited intrinsic healing potential, with only 30.3% healing by 12 months after ACLR. The process of healing took >6 months in half of the patients in whom it occurred. No new cases of full healing occurred beyond 12 months postoperatively. No significant risk factors for failure of full healing to occur were identified, but it is likely that this aspect of the study was underpowered.
6 months in half of the patients in whom it occurred. No new cases of full healing occurred beyond 12 months postoperatively. No significant risk factors for failure of full healing to occur were identified, but it is likely that this aspect of the study was underpowered.
Primary rotator cuff repairs in complex cases (older patient age, larger tear sizes, chronic tears) and revision repairs are at high risk for failure of healing.
To examine clinical outcomes and healing rates in complex and revision rotator cuff repairs with dermal allograft augmentation.
Case series; Level of evidence, 4.
A retrospective study was made of cases performed by 3 fellowship-trained surgeons via a uniform technique involving rotator cuff repairs with allograft augmentation. In all cases, a 1.5-mm, human, decellularized dermal graft was tied on top of the tendon at the medial row and compressed to the rotator cuff footprint using a double-row technique. Postoperative magnetic resonance imaging (MRI) was performed at a minimum of 6 months and American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and 12-Item Short Form Health Survey scores were collected at a minimum of 2 years postoperatively.
A total of 35 patients (23 revision repairs, 12 primary complex repairs) were included.