Comparative Analysis of Muscle Atrophy During Spaceflight, Nutritional Deficiency and Disuse in the Nematode Caenorhabditis elegans.

While spaceflight is becoming more common than before, the hazards spaceflight and space microgravity pose to the human body remain relatively unexplored. Astronauts experience muscle atrophy after spaceflight, but the exact reasons for this and solutions are unknown. Here, we take advantage of the nematode C. elegans to understand the effects of space microgravity on worm body wall muscle. We found that space microgravity induces muscle atrophy in C. elegans from two independent spaceflight missions. As a comparison to spaceflight-induced muscle atrophy, we assessed the effects of acute nutritional deprivation and muscle disuse on C. elegans muscle cells. We found that these two factors also induce muscle atrophy in the nematode. Finally, we identified clp-4, which encodes a calpain protease that promotes muscle atrophy. Mutants of clp-4 suppress starvation-induced muscle atrophy. Such comparative analyses of different factors causing muscle atrophy in C. elegans could provide a way to identify novel genetic factors regulating space microgravity-induced muscle atrophy.

Cytomegalovirus colitis induced segmental colonic hypoganglionosis in an immunocompetent patient: A case report.

BACKGROUND: Cytomegalovirus (CMV) colitis is usually seen in immunocompromised patients with risk factors such as human immunodeficiency virus infection, solid organ transplant, inflammatory bowel disease, or malignancy. Therefore, many clinicians usually do not consider the possibility of CMV colitis in immunocompetent patients. We reported a rare case of segmental colonic hypoganglionosis associated with CMV colitis in an immunocompetent patient. CASE SUMMARY: A 48-year-old woman with no underlying disease was admitted to our hospital for severe abdominal pain and constipation. Computed tomography of the abdomen showed diffuse dilatation of the small intestine and the entire colon. Initial sigmoidoscopic findings and result of polymerase chain reaction (PCR) for CMV revealed the compatible findings of CMV colitis, the patient was treated with intravenous ganciclovir. After treatment, sigmoidoscopic findings and CMV PCR results improved. However the patient continued to suffered from constipation. Eight months after the initial admission, patient visited the emergency department with severe abdominal pain and imaging revealed aggravation of fecal impaction and bowel dilatation. We performed subtotal colectomy to control patient's symptom. Histological examination of the resected specimen showed significantly reduced number of mature ganglion cells in the sigmoid colon compared to that in the proximal colon. CONCLUSION: Our case demonstrates that CMV colitis can develop even in patients with no other underlying disease, and that CMV colitis can be one of the causes for developing colonic hypoganglionosis.

Simple parameters predicting extrahepatic recurrence after curative hepatectomy for hepatocellular carcinoma.

Extrahepatic recurrence (EHR) after curative hepatectomy for hepatocellular carcinoma (HCC) is associated with a poor prognosis. We investigated the features of EHR and identified its predictive factors. This retrospective study included 398 treatment-naive patients who underwent curative hepatectomy for HCC at two tertiary hospitals. Multivariate Cox-regression analysis was performed to identify the variables associated with EHR. EHR was diagnosed in 94 patients (23.6%) over a median follow-up period of 5.92 years, most commonly in the lungs (42.6%). The 5-/10-year cumulative rates of HCC recurrence and EHR were 63.0%/75.6% and 18.1%/35.0%, respectively. The median time to EHR was 2.06 years. Intrahepatic HCC recurrence was not observed in 38.3% of patients on EHR diagnosis. On multivariate analysis, pathologic modified Union for International Cancer Control stage (III, IVa), surgical margin involvement, tumor necrosis, sum of tumor size > 7 cm, and macrovascular invasion were predictive factors of EHR. Four risk levels and their respective EHR rates were defined as follows: very low risk, 1-/5-year, 3.1%/11.6%; low risk, 1-/5-year, 12.0%/27.7%; intermediate risk, 1-/5-year, 36.3%/60.9%; and high risk, 1-year, 100.0%. Our predictive model clarifies the clinical course of EHR and could improve the follow-up strategy to improve outcomes.

Muscle and epidermal contributions of the structural protein ß-spectrin promote hypergravity-induced motor neuron axon defects in C. elegans.

Biology is adapted to Earth's gravity force, and the long-term effects of varying gravity on the development of animals is unclear. Previously, we reported that high gravity, called hypergravity, increases defects in the development of motor neuron axons in the nematode Caenorhabditis elegans. Here, we show that a mutation in the unc-70 gene that encodes the cytoskeletal ß-spectrin protein suppresses hypergravity-induced axon defects. UNC-70 expression is required in both muscle and epidermis to promote the axon defects in high gravity. We reveal that the location of axon defects is correlated to the size of the muscle cell that the axon traverses. We also show that mutations that compromise key proteins of hemidesmosomal structures suppress hypergravity-induced axon defects. These hemidesmosomal structures play a crucial role in coupling mechanical force between the muscle, epidermis and the external cuticle. We speculate a model in which the rigid organization of muscle, epidermal and cuticular layers under high gravity pressure compresses the narrow axon migration pathways in the extracellular matrix hindering proper axon pathfinding of motor neurons.

18F-FDG PET CT as a prognostic factor in hepatocellular carcinoma.

BACKGROUND/AIMS: To elucidate the role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) imaging as an independent prognostic factor in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A total of 104 patients with newly diagnosed HCC who underwent 18F-FDG-PET/CT imaging from 2009 to 2014 were reviewed retrospectively. The ratio of the maximal tumor standardized uptake value (SUV) to the mean mediastinum SUV (TSUVmax/MSUVmean) was evaluated as the predictive factor. RESULTS: A high TSUVmax/MSUVmean ratio (≥3.1) was significantly associated with tumor burden indices, including α-fetoprotein (p<0.001), amino transaminase (AST) (p=0.007), tumor size (p=0.043), Tumor, Node, and Metastasis (TNM) stage (p<0.001), and Barcelona Clinic Liver Cancer (BCLC) staging (p<0.001). The mortality rate was higher (48.1% vs. 23.1%, p<0.001) in patients with a high TSUVmax/MSUVmean ratio (≥3.1). Among the 47 patients who underwent transarterial chemoembolization (TACE), patients with a high TSUVmax/MSUVmean ratio (≥3.1) were more likely to have recurrence following TACE (18/19 vs. 18/28, p=0.016). CONCLUSION: A high TSUVmax/MSUVmean ratio on 18F-FDG-PET/CT imaging can serve as an independent prognostic factor in HCC and may predict tumor recurrence after TACE.

A case of ascending colonic xanthoma presenting as a lateral spreading tumor.

Gastrointestinal xanthomas are characterized by foamy cytoplasmic cells containing lipid in lamina propria, and occur almost in the gastric mucosa. Colonic xanthomas have been described in rare case. All reported colonic xanthomas were located in rectosigmoid. Rectosigmoid xanthomas have tended to exhibit small polypoid lesion, on the contrary flat in stomach. We report a case of xanthoma on ascending colon presenting as a laterally spreading tumor resected by endoscopic mucosal resection method.