Global, Regional, and National Burden of Spine Pain, 1990-2019: A Systematic Analysis of the Global Burden of Disease Study 2019.

OBJECTIVE: To describe the global, regional, national, and temporal trends in neck pain (NP) and low back pain (LBP) from 1990 to 2019 and analyze associations with age, sex, and sociodemographic index (SDI). DESIGN: Temporal trends analyses of the Global Burden of Disease 2019 data for global, regional, and national prevalence, incidence, and years lived with disabilities (YLDs) of NP and LBP from 1990 to 2019. SETTING: Not applicable. PARTICIPANTS: Not applicable. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): The temporal trends in prevalence, incidence, and YLDs of NP and LBP, and associations with age, sex, and SDI. RESULTS: Globally, the prevalence, incidence, and YLDs of NP and LBP significantly increased; however, the age-standardized rates of NP showed a stable trend, and those of LBP slightly decreased from 1990 to 2019. The burden of NP and LBP was higher in women than in men. Both NP and LBP exhibited similar age-related trends, with the total numbers and rates increasing with age and reaching their highest points in the middle- and old-aged groups, respectively, in 2019. Overall, the prevalence, incidence, and YLDs of NP and LBP were higher in regions with higher SDI over the 3 decades. CONCLUSIONS: NP and LBP impose significant major public health burden globally. Although both conditions are more frequent in women and middle-aged groups and tend to be prevalent in countries with high SDI, they have distinct temporal and regional patterns. By comprehending temporospatial trends in the disease burden of NP and LBP, policymakers and health care professionals can make future interventions and policies to effectively manage these conditions worldwide as well as to achieve equity in prevention, diagnosis, and treatment.

A Combined In Vitro and In Vivo Assessment of the Safety of the Yeast Strains Kluyveromyces marxianus A4 and A5 Isolated from Korean Kefir.

Kefir is a traditional fermented milk containing beneficial bacteria and yeasts. Despite Kluyveromyces marxianus, isolated from kefir, gaining increasing attention as a potential probiotic yeast owing to its biological function, Saccharomyces boulardii is the only species considered as a probiotic yeast. We evaluated the safety of K. marxianus strains A4 and A5, isolated from Korean kefir, in comparison with that of S. boulardii. Virulence attributes were preliminarily assessed in vitro including their ability of gelatin hydrolysis, pseudohyphae formation, and hemolysis. To evaluate in vivo safety, the strains were challenged in a healthy animal model, four-week-old female BALB/c mice. Mice were orally administered 0.2 mL of 0.9% sterilized saline (NC_S; n = 6), S. boulardii ATCC MYA-796 (high concentration, S.b_H; low concentration, S.b_L; n = 6 for each), K. marxianus A4 (high concentration, A4_H; low concentration, A4_L; n = 6 for each), or K. marxianus A5 (high concentration, A5_H; low concentration, A5_L; n = 6 for each) for 2 weeks. At study end, body weight, spleen and liver weights, and blood parameters were assessed. K. marxianus A4 and A5 were tested negative for gelatinase and hemolysis. Overall, hematological, plasma biochemical, and cytokine (interleukin-1ß and tumor necrosis factor-α) parameters were comparable between the experimental and negative control (NC) groups. Notably, the interleukin-6 level of the A5_H group was significantly lower than that of the NC group (p < 0.05), suggesting anti-inflammatory potential of K. marxianus A5.

Assessment of Cre-lox and CRISPR-Cas9 as tools for recycling of multiple-integrated selection markers in Saccharomyces cerevisiae.

We evaluated the Cre-lox and CRISPR-Cas9 systems as marker-recycling tools in Saccharomyces cerevisiae recombinants containing multiple-integrated expression cassettes. As an initial trial, we constructed rDNA-nontranscribed spacer- or Ty4-based multiple integration vectors containing the URA3 marker flanked by the loxP sequence. Integrants harboring multiple copies of tHMG1 and NNV-CP expression cassettes were obtained and subsequently transformed with the Cre plasmid. However, the simultaneous pop-out of the expression cassettes along with the URA3 marker hampered the use of Cre-lox as a marker-recycling tool in multiple integrants. As an alternative, we constructed a set of CRISPR-Cas9-gRNA vectors containing gRNA targeted to auxotrophic marker genes. Transformation of multiple integrants of tHMG1 and NNV-CP cassettes by the Cas9-gRNA vector in the presence of the URA3 (stop) donor DNA fragments generated the Ura- transformants retaining multiple copies of the expression cassettes. CRISPR-Cas9-based inactivation led to the recycling of the other markers, HIS3, LEU2, and TRP1, without loss of expression cassettes in the recombinants containing multiple copies of tHMG1, NNV-CP, and SfBGL1 cassettes, respectively. Reuse of the same selection marker in marker-inactivated S. cerevisiae was validated by multiple integrations of the TrEGL2 cassette into the S. cerevisiae strain expressing SfBGL1. These results demonstrate that introducing stop codons into selection marker genes using the CRISPR-Cas9 system with donor DNA fragments is an efficient strategy for markerrecycling in multiple integrants. In particular, the continual reuse of auxotrophic markers would facilitate the construction of a yeast cell factory containing multiple copies of expression cassettes without antibiotic resistance genes.