Precise and Efficient Nucleotide Substitution Near Genomic Nick via Noncanonical Homology-Directed Repair

CRISPR/Cas9, which generates DNA double-strand breaks (DSBs) at target loci, is a powerful tool for editing genomes when codelivered with a donor DNA template. However, DSBs, which are the most deleterious type of DNA damage, often result in unintended nucleotide insertions/deletions (indels) via mutagenic nonhomologous end joining. We developed a strategy for precise gene editing that does not generate DSBs. We show that a combination of single nicks in the target gene and donor plasmid (SNGD) using Cas9D10A nickase promotes efficient nucleotide substitution by gene editing. Nicking the target gene alone did not facilitate efficient gene editing. However, an additional nick in the donor plasmid backbone markedly improved the gene-editing efficiency. SNGD-mediated gene editing led to a markedly lower indel frequency than that by the DSB-mediated approach. We also show that SNGD promotes gene editing at endogenous loci in human cells. Mechanistically, SNGD-mediated gene editing requires long-sequence homology between the target gene and repair template, but does not require CtIP, RAD51, or RAD52. Thus, it is considered that noncanonical homology-directed repair regulates the SNGD-mediated gene editing. In summary, SNGD promotes precise and efficient gene editing and may be a promising strategy for the development of a novel gene therapy approach

Prevalence and risk factors for low back pain among professional cooks working in school lunch services

<p>Abstract</p> <p>Background</p> <p>The prevalence of self-reported low back pain among professional cooks was estimated to examine the effects of daily life conditions, job-related factors, and psychological factors on this disorder.</p> <p>Methods</p> <p>Data was collected using a mailed self-administered questionnaire.</p> <p>Results</p> <p>Of 7100 cooks, 5835 (82%) replied to the questionnaire, including 1010 men and 4825 women. The mean age was 41.4 for men and 47.5 for women. The prevalence of low back pain during a 1-month period was 72.2% among men and 74.7% among women, with no significant differences between groups. By logistic regression analyses, factors significantly associated with the prevalence of low back pain in 1 month were female gender (prevalence ratio [PR] 1.32; 95% CI, 1.03–1.68), current smoking (PR 1.57; 95% CI, 1.24–1.98), and past smoking (PR 1.35; 95% CI, 1.01–1.79). As for job-related factors, the number of cooked lunches per person (PR 1.28; 95% CI, 1.05–1.56), breaks in the morning session (PR 1.33; 95% CI, 1.13–1.56), kitchen environment (PR 1.09; 95%, CI, 1.03–1.15), and height of cooking equipment (PR 1.13; 95% CI, 1.08–1.19) were associated with the prevalence of low back pain. As for psychological factors, job satisfaction (PR 1.22; 95% CI, 1.03–1.45), stress at work (PR 1.68; 95% CI, 1.42–1.99), financial constraints (PR 1.23; 95% CI, 1.03–1.47), health-related stress (PR 1.31; 95% CI, 1.08–1.59) and worries about the future (PR 1.24; 95% CI, 1.01–1.52) were similarly associated.</p> <p>Conclusion</p> <p>Daily life conditions, job-related factors, and psychological factors are associated with the occurrence of low back pain. It is important to take comprehensive preventive measures to address a range of work and life conditions that can be improved to decrease the incidence of low back pain for professional cooks.</p

TRPC6 regulates phenotypic switching of vascular smooth muscle cells through plasma membrane potential-dependent coupling with PTEN

Vascular smooth muscle cells (VSMCs) play critical roles in the stability and tonic regulation of vascular homeostasis. VSMCs can switch back and forth between highly proliferative synthetic and fully differentiated contractile phenotypes in response to changes in the vessel environment. Although abnormal phenotypic switching of VSMCs is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty, how control of VSMC phenotypic switching is dysregulated in pathologic conditions remains obscure. We found that inhibition of canonical transient receptor potential 6 (TRPC6) channels facilitated contractile differentiation of VSMCs through plasma membrane hyperpolarization. TRPC6-deficient VSMCs exhibited more polarized resting membrane potentials and higher protein kinase B (Akt) activity than wild-type VSMCs in response to TGF-β1 stimulation. Ischemic stress elicited by oxygen-glucose deprivation suppressed TGF-β1-induced hyperpolarization and VSMC differentiation, but this effect was abolished by TRPC6 deletion. TRPC6-mediated Ca2+ influx and depolarization coordinately promoted the interaction of TRPC6 with lipid phosphatase and tensin homolog deleted from chromosome 10 (PTEN), a negative regulator of Akt activation. Given the marked up-regulation of TRPC6 observed in vascular disorders, our findings suggest that attenuation of TRPC6 channel activity in pathologic VSMCs could be a rational strategy to maintain vascular quality control by fine-tuning of VSMC phenotypic switching.Fil: Numaga-Tomita, Takuro. No especifíca;Fil: Shimauchi, Tsukasa. Kyushu University; JapónFil: Oda, Sayaka. No especifíca;Fil: Tanaka, Tomohiro. No especifíca;Fil: Nishiyama, Kazuhiro. Kyushu University; JapónFil: Nishimura, Akiyuki. Kyushu University; JapónFil: Birnbaumer, Lutz. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Mori, Yasuo. No especifíca;Fil: Nishida, Motohiro. Kyushu University; Japó

Multiple granulomatous lung lesions in a patient with Epstein-Barr-virus-induced mononucleosis and new-onset systemic lupus erythematosus: a case report

INTRODUCTION: Granulomatous lesions are commonly encountered abnormalities in pulmonary pathology, and often pose a diagnostic challenge. We report an unusual case of granulomatous lung disease with uncommon characteristics, which developed following Epstein-Barr-virus-induced mononucleosis and new-onset systemic lupus erythematosus. We aim to highlight a diagnostic approach for the condition and to raise awareness of the possibility of it being related to the immunological reaction caused by Epstein-Barr virus infection. CASE PRESENTATION: A 36-year-old Japanese man, who had been diagnosed with Epstein-Barr-virus-induced infectious mononucleosis, new-onset systemic lupus erythematosus, and secondary Sjögren’s syndrome three weeks previously, presented to our facility with fever and diffuse pulmonary infiltrates. A computed tomography scan of the chest revealed multiple small nodules in both lungs. Fiberoptic bronchoscopy with bronchoalveolar lavage revealed lymphocytosis with predominance of T lymphocytes. A histological examination of a lung biopsy taken during video-assisted thoracic surgery showed randomly distributed tiny granulomatous lesions with infiltration of eosinophils. The differential diagnoses included hypersensitivity pneumonitis, sarcoidosis, and pulmonary involvement of Crohn’s disease, systemic lupus erythematosus, and Sjögren’s syndrome, but the clinical and pathological findings were not consistent with any of these. Our patient’s condition did not improve; therefore, prednisolone therapy was started because of the possibility of specific immunological reactions associated with Epstein-Barr virus infection. After steroid treatment, our patient showed radiological and clinical improvement. CONCLUSIONS: To the best of our knowledge, this is the first case of a patient developing randomly distributed multiple granulomatous lung lesions with eosinophilic infiltrates after Epstein-Barr virus infection and systemic lupus erythematosus. On the basis of our data, we hypothesize that Epstein-Barr virus infection altered the immune response of our predisposed patient and contributed to the pathogenesis of the lung lesions. Our patient’s clinical response to steroid treatment was excellent

STAT6 expression in T cells, alveolar macrophages and bronchial biopsies of normal and asthmatic subjects

<p>Abstract</p> <p>Background</p> <p>Asthma is characterised by increased numbers of Th2-like cells in the airways and IgE secretion. Generation of Th2 cells requires interleukin (IL)-4 and IL-13 acting through their specific receptors and activating the transcription factor, signal transducer and activator of transcription 6 (STAT6). STAT6 knockout mice fail to produce IgE, airway hyperresponsiveness and bronchoalveolar lavage eosinophilia after allergen sensitisation, suggesting a critical role for STAT6 in allergic responses.</p> <p>Methods</p> <p>We have investigated the expression of STAT6 in peripheral blood T-lymphocytes, alveolar macrophages and bronchial biopsies from 17 normal subjects and 18 mild-moderate steroid-naïve stable asthmatic patients.</p> <p>Results</p> <p>STAT6 expression was variable and was detected in T-lymphocytes, macrophages and bronchial epithelial cells from all subjects with no difference between normal and stable asthmatic subjects.</p> <p>Conclusions</p> <p>STAT6 expression in different cells suggests that it may be important in regulating the expression of not only Th2-like cytokines in T cells of man, but may also regulate STAT-inducible genes in alveolar macrophages and airway epithelial cells.</p

Spontaneous Remission of Solitary-Type Infantile Myofibromatosis

Infantile myofibromatosis is a rare fibrous tumor of infancy. The cutaneous solitary type has typically an excellent prognosis. However, histologically, it is important to rule out leiomyosarcoma, which has a poor prognosis. The low frequency of mitosis was definitive for a diagnosis of infantile myofibromatosis. We present a cutaneous solitary-type case of infantile myofibromatosis. Following incisional biopsy, the tumor remitted spontaneously

Comparison of muscle quality and functional capacity between Japanese and Brazilian older individuals

Muscle quality is well-known to decrease with aging and is a risk factor for metabolic abnormalities. However, there is a lack of information on race-associated differences in muscle quality and other neuromuscular features related to functional performance. This study aimed to compare muscle quality, function, and morphological characteristics in Japanese and Brazilian older individuals. Eighty-four participants aged 65–87 years were enrolled in the study (42 Japanese: 23 men, 19 women, mean age 70.4 years; 42 Brazilians: 23 men, 19 women, mean age 70.8 years). Echo intensity (EI) and muscle thickness (MT) of the quadriceps femoris were measured using B-mode ultrasonography. A stepwise multiple linear regression analysis with EI as a dependent variable revealed that MT was a significant variable for Japanese participants (R2 = 0.424, P = 0.001), while MT and subcutaneous adipose tissue (SCAT) thickness were significant variables for Brazilian participants (R2 = 0.490, P = 0.001). A second stepwise multiple linear regression analysis was performed after excluding MT and SCAT thickness from the independent variables. Sex and age for Japanese participants (R2 = 0.381, P = 0.001) and lean body mass and body mass index for Brazilian participants (R2 = 0.385, P = 0.001) were identified as significant independent variables. The present results suggest that MT is closely correlated with muscle quality in Japanese and Brazilian older individuals. Increases in muscle size may induce decreases in intramuscular adipose tissue and/or connective tissues, which are beneficial for reducing the risks of metabolic impairments in Japanese and Brazilian older individuals

Dynamics of rheumatoid joint

In the present communication the recent works done by the Rheumatism Research Group of Department of Orthopedic Surgery, Okayama University, are described. The principal findings may briefly be summarized as follows. 1. Pathohistological pictures of the synovial membrane are classified into six types. Among them, Fibrinoid type and Follicular-Fibrosis type are the representative ones of chronic rheumatoid arthritis. 2. For the evaluation of the systemic as well as the local activities in rheumatoid arthritis and for judging the therapeutic effect, some indices have been established. 3. Injection of steroid hormones into the local joints fails to give satisfactory results in advanced, chronic rheumatoid arthritis. In such instances the flushing of the joint with physiological saline solution is effective. 4. In the case of chronic rheumatoid arthritis where the inflammation of hand and phalangeal joints is marked, RA-test gives rapid and more intense reaction, and most of such cases are of Follicular-Fibrosis type. 5. When lymph follicles appearing in the synovial membrane are stained when methyl green pyronine, the arrangement of lymphoid cells and plasma cells becomes distinctly clear. By micro-autoradiographic observations it can be seen that ³H-thymindine injected into the joint cavity is mostly ingested by the lymphoid cells in lymph follicles. 6. In the observation by the fluorescent antibody method multinuclear leucocytes found in the joint fluid and in the peripheral blood react with 19S and 7S-gamma-globulins. 7. When the serum and the joint fluid of the patient with rheumatoid arthritis are fractionated, they separate into three peaks at 19S, 7S, and 4S. Both S. S. C. A.-test and L. F. T. tests reveal the peak at 19S. The serum of chronic hepatitis positive to RA-test and the serum of rheumatoid arthritis are found to react immunologically the same to anti-&#946;2 M globulin sheep serum. 8. When the reticulo-endothelial system of rat is blocked by 900,000 molecules of poly-vinyl-pyrroridon, the ability of antibody production is diminished. 9. Chemical synovectomy of injecting osmic acid is effective to FibrinoidCoating type. Its action mechanism lies in the complete cleaning of the surface of synovial membrane. 10. By radiating synovectomy with 193Au a fairly good result can be expected. 198Au is ingested by those cells in the surface layer of the synovial membrane and also by histiocytes in the synovial membrane. When 5 mc of 198Au are injected into the knee joint, a marked necrosis of the synovial membrane occurs. When 198Au is added to the ascites cells of rabbit during the tissue culture, in the concentration of over 14 &#956;C degeneration of these cells can be recognized. 11. From the examination results of prognosis on those 25 cases with 41 rheumatoid knee joints after surgical synovectomy, it is considered that this method is indicated for Follicular-Fibrosis type. Ones with rheumatoid knee joint of Fibrinoid-Coating type gold sol treatment should be resorted to. In the cases of hand joints, surgical synovectemy is to be recommended at a relatively early stage.</p

Developmental genetic bases behind the independent origin of the tympanic membrane in mammals and diapsids

International audienceThe amniote middle ear is a classical example of the evolutionary novelty. Although paleontological evidence supports the view that mammals and diapsids (modern reptiles and birds) independently acquired the middle ear after divergence from their common ancestor, the developmental bases of these transformations remain unknown. Here we show that lower-to-upper jaw transformation induced by inactivation of the Endothelin1-Dlx5/6 cascade involving Goosecoid results in loss of the tympanic membrane in mouse, but causes duplication of the tympanic membrane in chicken. Detailed anatomical analysis indicates that the relative positions of the primary jaw joint and first pharyngeal pouch led to the coupling of tympanic membrane formation with the lower jaw in mammals, but with the upper jaw in diapsids. We propose that differences in connection and release by various pharyngeal skeletal elements resulted in structural diversity, leading to the acquisition of the tympanic membrane in two distinct manners during amniote evolution