Legionella longbeachae pneumonia: A case report and literature review in Japan

Herein, we report the case of a 74-year-old man diagnosed with Legionella pneumonia detected by Loop-Mediated Isothermal Amplification (LAMP) method, which was suspected to have been transmitted from the potting soil. Legionella longbeachae was identified in the sputum culture. The patient was intubated and maintained on mechanical ventilation. Antimicrobial therapy with azithromycin was also administered. His symptoms were resolved and he was discharged after 26 days of hospitalization. Legionella longbeachae pneumonia rarely occurs in Japan, and published literature of Legionella longbeachae pneumonia cases in Japan was reviewed. Patients with severe pneumonia exposed to potting soils, but with negative urinary antigen test results, should be examined by LAMP method.     

E and ID proteins regulate cell chirality and left–right asymmetric development in Drosophila

How left–right (LR) asymmetric forms in the animal body is a fundamental problem in Developmental Biology. Although the mechanisms for LR asymmetry are well studied in some species, they are still poorly understood in invertebrates. We previously showed that the intrinsic LR asymmetry of cells (designated as cell chirality) drives LR asymmetric development in the Drosophila embryonic hindgut, although the machinery of the cell chirality formation remains elusive. Here, we found that the Drosophila homologue of the Id gene, extra macrochaetae (emc), is required for the normal LR asymmetric morphogenesis of this organ. Id proteins, including Emc, are known to interact with and inhibit E‐box‐binding proteins (E proteins), such as Drosophila Daughterless (Da). We found that the suppression of da by wild‐type emc was essential for cell chirality formation and for normal LR asymmetric development of the embryonic hindgut. Myosin ID (MyoID), which encodes the Drosophila Myosin ID protein, is known to regulate cell chirality. We further showed that Emc‐Da regulates cell chirality formation, in which Emc functions upstream of or parallel to MyoID. Abnormal Id‐E protein regulation is involved in various human diseases. Our results suggest that defects in cell shape may contribute to the pathogenesis of such diseases.     

The JAK2/STAT3 signaling pathway is required for growth of CD44⁺CD24⁻ stem cell-like breast cancer cells in human tumors

Intratumor heterogeneity is a major clinical problem because tumor cell subtypes display variable sensitivity to therapeutics and may play different roles in progression. We previously characterized 2 cell populations in human breast tumors with distinct properties: CD44+CD24- cells that have stem cell-like characteristics, and CD44-CD24+ cells that resemble more differentiated breast cancer cells. Here we identified 15 genes required for cell growth or proliferation in CD44+CD24- human breast cancer cells in a large-scale loss-of-function screen and found that inhibition of several of these (IL6, PTGIS, HAS1, CXCL3, and PFKFB3) reduced Stat3 activation. We found that the IL-6/JAK2/Stat3 pathway was preferentially active in CD44+CD24- breast cancer cells compared with other tumor cell types, and inhibition of JAK2 decreased their number and blocked growth of xenografts. Our results highlight the differences between distinct breast cancer cell types and identify targets such as JAK2 and Stat3 that may lead to more specific and effective breast cancer therapies.     

Association of Fusobacterium nucleatum with clinical and molecular features in colorectal serrated pathway

Human gut microbiota is being increasingly recognized as a player in colorectal cancers (CRCs). Evidence suggests that Fusobacterium nucleatum (F. nucleatum) may contribute to disease progression and is associated with CpG island methylator phenotype (CIMP) and microsatellite instability (MSI) in CRCs; however, to date, there are no reports about the relationship between F. nucleatum and molecular features in the early stage of colorectal tumorigenesis. Therefore, we investigated the presence of F. nucleatum in premalignant colorectal lesions. In total, 465 premalignant lesions (343 serrated lesions and 122 non‐serrated adenomas) and 511 CRCs were studied. We determined the presence of F. nucleatum and analyzed its association with molecular features including CIMP, MSI and microRNA‐31 status. F. nucleatum was detected in 24% of hyperplastic polyps, 35% of sessile serrated adenomas (SSAs), 30% of traditional serrated adenomas (TSAs) and 33% of non‐serrated adenomas. F. nucleatum was more frequently detected in CIMP‐high premalignant lesions than in CIMP‐low/zero lesions (p = 0.0023). In SSAs, F. nucleatum positivity increased gradually from sigmoid colon to cecum (p = 0.042). F. nucleatum positivity was significantly higher in CRCs (56%) than in premalignant lesions of any histological type (p < 0.0001). In conclusion, F. nucleatum was identified in premalignant colorectal lesions regardless of histopathology but was more frequently associated with CIMP‐high lesions. Moreover, F. nucleatum positivity increased according to histological grade, suggesting that it may contribute to the progression of colorectal neoplasia. Our data also indicate that F. nucleatum positivity in SSAs may support the “colorectal continuum” concept.     

Independent Risk Factors for Positive and Negative Symptoms in Patients with Diabetic Polyneuropathy

Patients with diabetes occasionally develop diabetic polyneuropathy (DPN), which is characterized by both positive symptoms such as pain and negative symptoms such as numbness/dysesthesia. However, these symptoms have always been collectively analyzed to determine their risk factors. This study aimed to independently analyze the risk factors for neuropathic pain and numbness/dysesthesia in DPN patients. In total, 298 patients with diabetes (age: 61.1 ± 10.4 years; 176 male) were included. The relationships among the incidence of DPN and its clinical parameters were determined using logistic regression models. Then, the statistical model was applied in two groups of DPN patients: those with pain only or both pain and the negative symptoms (pain group; n = 25) and those with the negative symptoms only or both pain and the negative symptoms (numbness/dysesthesia group; n = 60). All logistic regression models were adjusted for the duration of diabetes, glycosylated hemoglobin levels, and age. The depression score was higher for patients with DPN than for those without, although it did not reach an abnormal level. An abnormal Achilles tendon reflex (ATR) and insulin treatment, but not smoking, hypertension, hyperlipidemia, and diabetic retinopathy, were associated with DPN. Furthermore, female sex and an abnormal ATR and insulin treatment were significant clinical features in the pain and numbness/numbness groups, respectively. Overweight and obesity were the common clinical features in both groups. We conclude that the positive and negative symptoms of DPN possibly have independent risk factors, suggesting different underlying mechanisms and the need for separate diagnosis and treatment.     

Detection of sub-centimeter lesions using digital TOF-PET/CT system combined with Bayesian penalized likelihood reconstruction algorithm

Annals of Nuclear Medicine - Many advances in PET/CT technology can potentially improve image quality and the ability to detect small lesions. A new digital TOF-PET/CT scanner based on silicon...