Timing mechanism and effective activation energy concerned with aging and lifespan in the long-lived and thermosensory mutants of Caenorhabditis elegans

The lifespans of many poikilothermic animals, including the nematode Caenorhabditis elegans, depend significantly on environmental temperature. Using long-living, thermosensory mutants of C. elegans, we tested whether the temperature dependency of the mean lifespan is compatible with the Arrhenius equation, which typically represents one of the chemical reaction rate theories. The temperature dependency of C. elegans was the Arrhenius type or normal, but daf-2(e1370) mutants were quite different from the others. However, taking into account the effect of the thermal denaturation of DAF-2 with the temperature, we showed that our analyzed results are compatible with previous ones. We investigated the timing mechanism of one parameter (the onset of biodemographic aging (t₀)) in the lifespan equation by applying the RNAi feeding method to daf-2 mutants in order to suppress daf-16 activity at different times during the life cycle. In summary, we further deepened the biological role of two elements, t₀ and z (the inverse of the aging rate), in the lifespan equation and mean lifespan formulated by our diffusion model z² = 4Dt₀, where z is composed of t₀ and D (the diffusion constant).     

Pemphigus with thymoma improved by thymectomy: report of a case

A 53-year-old female with pemphigus vulgaris received treatment with prednisolone for 3 years. On chest computed tomography performed at follow-up, an anterior–mediastinal tumor (4 cm × 3 cm) was detected and diagnosed as a thymoma. Although amyosthenia was absent, the patient’s anti-acetylcholine-receptor antibody level was high, and she was positive for anti-desmoglein 3 antibodies. She underwent extended thymectomy in the same year, following which both the anti-acetylcholine receptor antibody and the anti-desmoglein 3 antibody levels were normalized. The patient’s skin symptoms improved, and the steroid dose was gradually lowered and finally discontinued 4 years postoperatively. Extended thymectomy may be an effective therapy for treating patients with pemphigus.     

Hairy polyp can be lethal even when small in size

A case of sudden cardiopulmonary arrest in a 3‐month‐old girl is presented. The patient had barely recovered from hypoxic encephalopathy when she presented with repeated respiratory distress. Computed tomography and endoscopic analysis revealed a shiny polyp in the lateral wall of the nasopharynx, and this polyp was suspected to be the main cause of respiratory distress. After referral to our hospital, surgical removal was performed, and the histopathological diagnosis was hairy polyp. Hairy polyp is a rare congenital benign tumor that sometimes induces respiratory distress. This polyp can potentially induce a life‐threatening event. In a systematic review of 40 reported cases, polyps of ≤3.0 cm in diameter have a higher risk of respiratory distress than do those >3.0 cm in diameter (P = 0.01). Small hairy polyps may be lethal because of delayed diagnosis. To locate small hairy polyps, physicians should not hesitate to perform further examination because there is the possibility of oversight with only physical examination.     

First Japanese case of atypical progeroid syndrome/atypical Werner syndrome with heterozygous LMNA mutation

Atypical progeroid syndrome (APS), including atypical Werner syndrome (AWS), is a progeroid syndrome involving heterozygous mutations in the LMNA gene encoding the nuclear protein lamin A/C. We report the first Japanese case of APS/AWS with a LMNA mutation (p.D300N). A 53‐year‐old Japanese man had a history of recurrent severe cardiovascular diseases as well as brain infarction and hemorrhages. Although our APS/AWS patient had overlapping features with Werner syndrome (WS), such as high‐pitched voice, scleroderma, lipoatrophy and atherosclerosis, several cardinal features of WS, including short stature, premature graying/alopecia, cataract, bird‐like face, flat feet, hyperkeratosis on the soles and diabetes mellitus, were absent. In immunofluorescence staining and electron microscopic analyses of the patient's cultured fibroblasts, abnormal nuclear morphology, an increase in small aggregation of heterochromatin and a decrease in interchromatin granules in nuclei of fibroblasts were observed, suggesting that abnormal nuclear morphology and chromatin disorganization may be associated with the pathogenesis of APS/AWS.     

Endoscopically proven case of rapid esophagogastric variceal progression and rupture as a result of portal hypertension with liver sarcoidosis

Sarcoidosis is a multi‐systemic disease of unknown etiology that results in the development of non‐caseating epithelioid granulomas. The liver is the third most frequently involved organ after the lymph nodes and the lungs. Most cases of liver sarcoidosis do not present with symptoms and involve minimal liver dysfunction, but some cases display progression to portal hypertension and liver cirrhosis, and finally to liver failure. The mechanism and the risk of progression in liver sarcoidosis are still unknown because of the diagnostic difficulty associated with this condition, and because follow‐up examinations can only be done in an invasive manner. Here, we present an informative case of liver sarcoidosis with rapid progression of esophagogastric varices. Four months prior to the definitive diagnosis, no signs of varices were observed on endoscopy, and developmentof esophagogastric varices, rapid progression, and eventual rupture occurred in a short period of time. A liver biopsy, carried out after endoscopic sclerotherapy, revealed that granulomas primarily affected the portal area without fibrotic and cirrhotic changes, which is considered a primary cause of portal hypertension and esophagogastric varices. Following the liver biopsy, the patient was given systemic steroids and is currently receiving outpatient care. Thus, we should consider the possibility that liver sarcoidosis, even in the absence of cirrhotic changes, can cause serious events such as esophagogastric variceal rupture following rapid progression as a result of portal hypertension.