In contrast to ventricular myocytes, the structural and functional importance of atrial transverse tubules (T-tubules) is not fully understood. Therefore, we investigated the ultrastructure of T-tubules of living rat atrial myocytes in comparison with ventricular myocytes. Nanoscale cell surface imaging by scanning ion conductance microscopy (SICM) was accompanied by confocal imaging of intracellular T-tubule network, and the effect of removal of T-tubules on atrial excitation-contraction coupling (EC-coupling) was observed. By SICM imaging, we classified atrial cell surface into 4 subtypes. About 38% of atrial myocytes had smooth cell surface with no clear T-tubule openings and intracellular T-tubules (smooth-type). In 33% of cells, we found a novel membrane nanostructure running in the direction of cell length and named it 'longitudinal fissures' (LFs-type). Interestingly, T-tubule openings were often found inside the LFs. About 17% of atrial cells resembled ventricular myocytes, but they had smaller T-tubule openings and a lower Z-groove ratio than the ventricle (ventricular-type). The remaining 12% of cells showed a mixed structure of each subtype (mixed-type). The LFs-, ventricular-, and mixed-type had an appreciable amount of reticular form of intracellular T-tubules. Formamide-induced detubulation effectively removed atrial T-tubules, which was confirmed by both confocal images and decreased cell capacitance. However, the LFs remained intact after detubulation. Detubulation reduced action potential duration and L-type Ca2+ channel (LTCC) density, and prolonged relaxation time of the myocytes. Taken together, we observed heterogeneity of rat atrial T-tubules and membranous ultrastructure, and the alteration of atrial EC-coupling by disruption of T-tubules.

In contrast to ventricular myocytes, the structural and functional importance of atrial transverse tubules (T-tubules) is not fully understood. Therefore, we investigated the ultrastructure of T-tubules of living rat atrial myocytes in comparison with ventricular myocytes. Nanoscale cell surface imaging by scanning ion conductance microscopy (SICM) was accompanied by confocal imaging of intracellular T-tubule network, and the effect of removal of T-tubules on atrial excitation-contraction coupling (EC-coupling) was observed. By SICM imaging, we classified atrial cell surface into 4 subtypes. About 38% of atrial myocytes had smooth cell surface with no clear T-tubule openings and intracellular T-tubules (smooth-type). In 33% of cells, we found a novel membrane nanostructure running in the direction of cell length and named it 'longitudinal fissures' (LFs-type). Interestingly, T-tubule openings were often found inside the LFs. About 17% of atrial cells resembled ventricular myocytes, but they had smaller T-tubule openings and a lower Z-groove ratio than the ventricle (ventricular-type). The remaining 12% of cells showed a mixed structure of each subtype (mixed-type). The LFs-, ventricular-, and mixed-type had an appreciable amount of reticular form of intracellular T-tubules. Formamide-induced detubulation effectively removed atrial T-tubules, which was confirmed by both confocal images and decreased cell capacitance. However, the LFs remained intact after detubulation. Detubulation reduced action potential duration and L-type Ca2+ channel (LTCC) density, and prolonged relaxation time of the myocytes. Taken together, we observed heterogeneity of rat atrial T-tubules and membranous ultrastructure, and the alteration of atrial EC-coupling by disruption of T-tubules.

Anoctamin 5 (ANO5)/TMEM16E belongs to a member of the ANO/TMEM16 family member of anion channels. However, it is a matter of debate whether ANO5 functions as a genuine plasma membrane chloride channel. It has been recognized that mutations in the ANO5 gene cause many skeletal muscle diseases such as limb girdle muscular dystrophy type 2L (LGMD2L) and Miyoshi muscular dystrophy type 3 (MMD3) in human. However, the molecular mechanisms of the skeletal myopathies caused by ANO5 defects are poorly understood. To understand the role of ANO5 in skeletal muscle development and function, we silenced the ANO5 gene in C2C12 myoblasts and evaluated whether it impairs myogenesis and myotube function. ANO5 knockdown (ANO5-KD) by shRNA resulted in clustered or aggregated nuclei at the body of myotubes without affecting differentiation or myotube formation. Nuclear positioning defect of ANO5-KD myotubes was accompanied with reduced expression of Kif5b protein, a kinesin-related motor protein that controls nuclear transport during myogenesis. ANO5-KD impaired depolarization-induced [Ca²⁺]i transient and reduced sarcoplasmic reticulum (SR) Ca²⁺ storage. ANO5-KD resulted in reduced protein expression of the dihydropyridine receptor (DHPR) and SR Ca²⁺-ATPase subtype 1. In addition, ANO5-KD compromised co-localization between DHPR and ryanodine receptor subtype 1. It is concluded that ANO5-KD causes nuclear positioning defect by reduction of Kif5b expression, and compromises Ca²⁺ signaling by downregulating the expression of DHPR and SERCA proteins.
Active Transport, Cell Nucleus ; Calcium Channels, L-Type ; Cell Membrane ; Chloride Channels ; Humans ; Muscle Development ; Muscle Fibers, Skeletal ; Muscle, Skeletal ; Muscular Diseases ; Muscular Dystrophies ; Muscular Dystrophies, Limb-Girdle ; Myoblasts ; RNA, Small Interfering ; Ryanodine Receptor Calcium Release Channel ; Sarcoplasmic Reticulum

PURPOSE: Tumor regression grade (TRG) is predictive of therapeutic response in rectal cancer patients after chemoradiotherapy (CRT) followed by curative resection. However, various TRG systems have been suggested, with subjective categorization, resulting in interobserver variability. This study compared the prognostic validity of four different TRG systems in order to identify the most ideal TRG system. MATERIALS AND METHODS: This study included 933 patients who underwent preoperative CRT and curative resection. Primary tumors alone were graded according to the American Joint Committee on Cancer (AJCC), Dworak, and Ryan TRG systems, and both primary tumors and regional lymph nodes were graded according to a modified Dworak TRG system. The ability of each TRG system to predict recurrence-free survival (RFS) and overall survival (OS) was analyzed using chi-square and C statistics. RESULTS: All four TRG systems were significantly predictive of both RFS and OS (p < 0.001 each), however none was a better predictor of prognosis than ypStage. Among the four TRGs, the mDworak TRG system was a better predictor of RFS and OS than the AJCC, Dworak, and Ryan TRG systems, and both the chi-square and C statistics were higher for the former, although the differences were not statistically significant. The combination of ypStage and the modified Dworak TRG better predicted RFS and OS than ypStage alone. CONCLUSION: The modified Dworak TRG system for evaluation of entire tumors including regional lymph nodes is a better predictor of survival than current TRG systems for evaluation of the primary tumor alone.
Chemoradiotherapy* ; Humans ; Joints ; Lymph Nodes ; Observer Variation ; Prognosis ; Rectal Neoplasms*

Colonoscopy is a widely used diagnostic and therapeutic intervention with an excellent safety profile. Although an intraperitoneal hemorrhage is a rare complication after colonoscopy, and usually associated with splenic injury or solid organ pathology, it is potentially serious and can be life-threatening. We report a rare case of spontaneous intraperitoneal hemorrhage after diagnostic colonoscopy without splenic injury or intra-abdominal abnormality, known as idiopathic spontaneous intraperitoneal hemorrhage. This case emphasizes that physicians should be aware of the emergence of acute abdomen after colonoscopy.
Abdomen ; Abdomen, Acute ; Colonoscopy ; Hemoperitoneum ; Hemorrhage ; Spleen

Although assisted reproductive technology is associated with higher rates of interstitial pregnancy and heterotopic pregnancy, heterotopic pregnancy after bilateral salpingectomy is still extremely rare. We report a case of heterotopic pregnancy after bilateral salpingectomy in an in vitro fertilization/embryo transfer patient, who underwent cornual resection by laparotomy due to ruptured cornual pregnancy. However, 3 days after surgery, the remaining intrauterine pregnancy miscarried, and a dilatation and curettage was performed.
Dilatation and Curettage ; Embryo Transfer ; Embryonic Structures ; Female ; Fertilization in Vitro ; Humans ; Laparotomy ; Pregnancy ; Pregnancy, Heterotopic ; Reproductive Techniques, Assisted ; Salpingectomy

Primary ovarian choriocarcinoma arising from a germ cell is an extremely rare occurrence, especially in postmenopausal women, and the prognosis is poor. Non-gestational choriocarcinoma of the ovary (NGCO) accounts for 0.6% or less of all ovarian neoplasms. It is important to distinguish gestational choriocarcinomas of the ovary (GCO) from other carcinomas because of the poor prognosis of NGCO. We describe a case of NGCO with lung metastasis in a 55 year old woman, which we present together with a brief review of the literature.
Choriocarcinoma ; Choriocarcinoma, Non-gestational ; Female ; Germ Cells ; Humans ; Lung ; Neoplasm Metastasis ; Ovarian Neoplasms ; Ovary ; Postmenopause ; Pregnancy ; Prognosis

The limb-girdle muscular dystrophy type 2A (LGMD2A) is a recessively inherited disease caused by a mutation of the calpain 3 gene (CAPN3), and is considered one of the most prevalent subtypes of limb-girdle muscular dystrophy (LGMD). In this study, we aimed to identify CAPN3 mutations and to characterize the phenotype of Korean patients with LGMD2A. Among 35 patients with LGMD, four patients, who showed calpain 3 deficiency on western blot analysis, were analyzed in this study. Total RNA extracted from frozen muscle tissue was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using six primer pairs covering all coding sequences of CAPN3, and direct sequencing was performed. Clinical and pathological features of the patients were also reviewed. We found four different mutations in five alleles from three patients. Of the pathogenic mutations identified, two were novel (c.2125T>C and c.2355-2357delTTC), and the others had been reported elsewhere (c.440G>C, c.1076C>T). All patients showed a high CK level with predominant proximal leg weakness, and the onset was in their childhood except for one patient. Among two novel CAPN3 mutations, one was a missense mutation (c.2125T>C [p.709Ser>Pro]), and the other was a small in-frame deletion causing omission of a single amino acid (c.2355-2357delTTC [p.786delPhe]). The clinical features of our patients were generally compatible with the characteristics of LGMD2A patients described in the previous studies.
Adolescent ; Adult ; Amino Acid Sequence ; Base Sequence ; Calpain/*genetics ; DNA Primers/chemistry ; Female ; Humans ; Korea ; Male ; Middle Aged ; Molecular Sequence Data ; Muscle Proteins/*genetics ; Muscular Dystrophies, Limb-Girdle/*genetics ; *Mutation ; Sequence Homology, Amino Acid

BACKGROUND: The monoclonal antibody M30 recognizes a neoepitope of cytokeratin 18 that's produced during the process of apoptosis, and it is reactive in formalin-fixed, paraffin-embedded tissue. The detailed nature of apoptosis in colorectal cancer is unclear, especially in regard to the MSI status and the clinicopathologic factors. The purpose of this study was to elucidate the apoptosis assessed by M30 immunoreactivity in colorectal cancer and its relationship with the MSI status and the various clinicopathologic factors of colorectal cancers. METHODS: 101 colorectal cancers were classified according to levels of MSI as 12 MSI-H, 4 MSI-L and 85 MSS. Apoptosis was quantified by immunohistochemistry with using M30 CytoDEATH anti-body. RESULTS: The apoptotic index assessed by M30 was significantly increased in the MSI-H and MSI-L colorectal cancer compared to that in the MSS colorectal cancer. Right sided colon cancer showed a significant higher apoptotic index than did the left sided colon cancer. There was also a tendency for decreased apoptosis in metastatic colorectal cancers (Duke's stage D). There was somewhat of an increase of apoptosis in colorectal cancers with mucinous carcinoma and medullary carcinoma, and also in the colorectal cancers with an increased TIL count, but this was not statistically significant. CONCLUSION: M30 immunoreactivity is a valuable method to detect apoptosis in formalin-fixed, paraffin-embedded tissue and it might explain that MSI-H colorectal cancer shows better clinical behavior than MSS colorectal cancer in regard to the increased apoptosis.
Adenocarcinoma, Mucinous ; Apoptosis* ; Carcinoma, Medullary ; Colonic Neoplasms ; Colorectal Neoplasms* ; Immunohistochemistry ; Keratin-18 ; Microsatellite Instability

PURPOSE: We wanted to measure the vascular pedicle width (VPW) in normal Korean adults and correlate the VPW with the body physique and we also wanted to establish the index for normal VPWs, which could be utilized in reading chest PAs. MATERIALS AND METHODS: The VPW was measured on the posteroanterior (PA) chest radiographs of 262 normal Korean adults (134 men and 128 women, age range: 22-88 years, mean age: 45.2 years), who visited the hospital for a general health examination. The relationship between the VPW and the height and the Body Mass Index (BMI) was evaluated. Correlations between height and the thoracic spine length (TSL) and between the BMI and the lateral chest wall thickness (CWT) were analyzed as well. RESULTS: The mean VPW was 47.4 (+/-6.4) mm. The VPW was positively correlated with the height (p<0.01) and the BMI (p<0.01) of the subject. The patient's height was well correlated with the TSL, and the BMI was correlated with the CWT (r=0.75, r=0.76). The table for the normal VPWs according to patient's TSL and CWT was established. CONCLUSION: By measuring the TSL and the CWT on chest PA, which reflect the height and BMI, respectively, and by utilizing the provided table for the normal VPW, we can determine the normality of a patient's VPW.
Adult* ; Blood Vessels ; Body Mass Index ; Female ; Humans ; Male ; Radiography, Thoracic ; Spine ; Thoracic Wall ; Thorax*