• International Journal of Industrial Entomology and Biomaterials
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• v.16 no.1
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• pp.29-35
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• 2008

The midgut epithelium of Indian honey bee Apis cerana indica is consist of digestive cells and small regenerative cells. The regenerative cells are placed in the nests scattered among the digestive cells. During metamorphosis the midgut of Apis cerana indica is remodeled. The larval midgut epithelium and muscular sheath digested partially at the end of larval period and thrown out in the form of debris in the lumen. The new epithelium is formed by the proliferation of the regenerative cells and during pupation reorganization of midgut layer occurs. The ultrastuctural studies shows that the regenerative cells are in contact with degenerative cells by the cytoplasmic extension which have many septed and gap junctions in the fifth instar larvae. In developing pupae reorganization of the midgut epithelium is continued whereas in the pharate adult the midgut wall shows, characteristic of adult midgut epithelium with pycnotic nuclei in some cells.

• Molecules and Cells
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• v.39 no.4
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• pp.358-366
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• 2016

The digestive system is gaining interest as a major regulator of various functions including immune defense, nutrient accumulation, and regulation of feeding behavior, aside from its conventional function as a digestive organ. The Drosophila midgut epithelium is completely renewed every 1-2 weeks due to differentiation of pluripotent intestinal stem cells in the midgut. Intestinal stem cells constantly divide and differentiate into enterocytes that secrete digestive enzymes and absorb nutrients, or enteroendocrine cells that secrete regulatory peptides. Regulatory peptides have important roles in development and metabolism, but study has mainly focused on expression and functions in the nervous system, and not much is known about the roles in endocrine functions of enteroendocrine cells. We systemically examined the expression of 45 regulatory peptide genes in the Drosophila midgut, and verified that at least 10 genes are expressed in the midgut enteroendocrine cells through RT-PCR, in situ hybridization, antisera, and 25 regulatory peptide-GAL transgenes. The Drosophila midgut is highly compartmentalized, and individual peptides in enteroendocrine cells were observed to express in specific regions of the midgut. We also confirmed that some peptides expressed in the same region of the midgut are expressed in mutually exclusive enteroendocrine cells. These results indicate that the midgut enteroendocrine cells are functionally differentiated into different subgroups. Through this study, we have established a basis to study regulatory peptide functions in enteroendocrine cells as well as the complex organization of enteroendocrine cells in the Drosophila midgut.

• Advances in pediatric surgery
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• v.10 no.2
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• pp.112-116
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• 2004

Midgut volvulus secondary to intestinal malrotation usually presents within the first month of life. Diagnostic delay may result in midgut infarction and mortality. In this retrospective study, we review seventeen cases of midgut volvulus to assess the importance of early recognition for midgut volvulus in pediatric patients of any age.. These patients were diagnosed as having a midgut volvulus by operation at Ewha Womans University Hospital. Eleven patients (64.7 %) were less than 1 month of age, and fifteen were boys (88.2 %). The mean gestational age was 38.3 weeks and the birth weight was 3.1 kg. Eight patients (47.1 %) had one or more combined anomalies such as heart malformation, brain ischemia, Down's syndrome or duodenal atresia. Vomiting was the most common symptom. Only thirteen patients underwent preoperative diagnostic procedures; 13 abdominal sonography demonstrated the whirlpool sign in 8 patients, upper gastrointestinal tract roentgenography showed a cork-screw pattern in 7 patients, and barium enema or small bowel series demonstrated positive findings in 7 patients. A Ladd's procedure was was formed on all patients.. There was no mortality or severe morbidity such as short bowel syndrome. Midgut volvulus should be included in the differential diagnosis in any infant or child who presents with the symptoms of acute abdomen, especially with vomiting.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.30-36
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• 2007

Intestinal malrotation is usually asymptomatic and most often is found during abdominal exploration for other surgical diseases. However, a serious complication of intestinal malrotation, midgut volvulus is a true surgical emergency of childhood. The clinical findings, diagnostic procedures, treatment, and prognosis of midgut volvulus were reviewed by a retrospective study. Between 1980 and 2005, 29 patients with midgut volvulus ranging in age from 1 day and 15 years were treated at HanYang University Hospital. Seventy-nine percent of the patients presented before 1 month of age. Midgut volvulus occurred 2 times more frequently in male. The clinical findings were bilious vomiting (96.6 %), irritability (34.5 %), abdominal distention (13.8 %), abdominal pain (10.3 %), and palpable abdominal mass (6.9 %). The diagnosis was made by abdominal simple x-ray (17.2 %), upper gastro-intestinal contrast study (37.9 %), abdominal sonogram (20.7 %), abdominal CT (3.4 %), and abdominal exploration (20.7 %). Among the 29 patients, 5 patients developed gangrene of small intestine due to strangulation and underwent resection of bowel. Two patients died due to sepsis.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.1 no.1
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• pp.133-137
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• 1998

Although midgut volvulus is clinically characterized by bilous vomiting and abdominal distention, plain abdominal X-ray is usually non-specific and therefore it can be misdiagnosed to other diseases. Upper gastrointestinal contrast study and computed tomography have been used as a routine diagnostic tool but it takes cost and time. Abdominal ultrasonography is a relatively good alternatives in diagnosing midgut volvulus and it relatively saves cost and time. But case presentation of midgut volvulus diagnosed with abdominal ultrasonography are rarely found in literature. We experienced a 6 month old girl who had come to our hospital with bilous vomiting and was diagnosed as midgut volvulus with ultrasonography. Thus we report this case with the presentation of typical ultrasonographic findings of midgut volvulus.

• Applied Microscopy
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• v.26 no.4
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• pp.421-430
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• 1996

The endocrine cells in the midgut epithelium of the Japanese cockroach, Periplaneta japonica were observed by the light and electron microscopy. The midgut epithelium of the last instar larva and adult cockroach consisted of principal columnar cells, regenerative cells, and secretory granular cells. Midgut endocrine cells were positioned basally as a cone-shaped single cell in the epithelium or underneath the regenerative crypt cells. When midgut epithelium grows and the cell composing it transforms, between the endocrine cells and regenerative cells were made desmosome type junction and large vesicular shaped stretches of loose contact. The endocrine cells were characterized by a clear cytoplasm with abundant Golgi complex and numerous secretory granules. The secretory granules in the cell were spherical and electron dense with their diameter of $200{\sim}400nm$. The secretory granules have been observed as discharged by exocytosis on the basal and lateral side of the cell.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.117-125
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• 2010

The tropical tasar silkworms, Antheraea mylitta (D) produce famous silk 'Kosa' in central part of India. Due to outdoor rearing it became susceptible to viral infection including cytoplasmic polyhedrosis virus (CPV). The common mode of entry of cytoplasmic polyhedrosis virus is per os and cause gresserie disease to the larvae. Histopathological studies elucidated the insect CPV virus produces infective polyhedral inclusion bodies (PIBs) in the midgut cell cytoplasm of virus infected fifth instar larvae. The PIBs multiply enormously in the cytoplasm without invading the nucleus. Ultrastructural studies confirmed the pathological effects of CPV on in midgut cell cytoplasm. The multiplication of polyhedral inclusion bodies took place into the vacuoles and form virogenic stromata in the cytoplasm of cells. However, the encapsulations of polyhedral inclusion bodies into the polyhedrin protein occurred and polyhedra were released into the lumen. At the late stage of infection, cells showed the regressed cytoplasmic organelles with large vacuoles and elongated mitochondria. Hence, the horizontal transmission of CPV causing the midgut cells disintegration in the tasar silkworm, Antheraea mylitta (D) confirmed during infection.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.95-99
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• 1995

Acid phosphatase(AP) of he aphid, Megoura crassicauda and the major component of the lady beetle's artificial diet, fresh chicken liver, was adapted as a model protein to study the digestion of diet proteins in the midgut of Harmonia axyridis. The lady beetle did not secrete its own AP into the lumen of the midgut. The aphid and the live chicken liver had AP which was still alive in enzymatic activity from the extract of the lumen of the midgut of the lady beetle. The digestive ability of the lady beetle on proteins turned out to be different depending on food sources. In the lumen of the midgut of the lady beetle, though most of AP of live chicken liver lost its activity withtin 12 hours, that of M. cassicauda kept strong enzymatic activity up to 24 hours.

• Journal of Sericultural and Entomological Science
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• v.26 no.1
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• pp.30-34
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• 1984

In order to investigate an endocrinological effect on metamorposis of the midgut in silkworm, Bombyx mori, 20-hydroxyecdysone and rude extract of brain (PTTH) were injected into pupal isolated abdomens, devoid of prothoracic glands and also in the brainless diapausing pupae with the prothoracic glands (so-called dauer pupae). When ecdysone was assayed abdomens, drastic morphological changes occurred in the midgut. The wet weights of midguts were found decrease as like the normal pupae at metamorphosis. Proteineous changes in epithelial midgut were also observed; pupal specific proteins (PSP) vanished while the adult proteins were newly synthesized. Similar results were also found in the changes of protein in the midgut of dauer pupae by injecting ecdysone and PTTH.

• The Korean Journal of Zoology
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• v.25 no.2
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• pp.63-70
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• 1982

The activity, properties, and distribution of midgut protease during metamorphosis in Pieris rapae L. are determined using spectrophotometer, ultracentrifuge and agar gel electrophoresis. Proteolytic activity of midgut reaches the peak just before ecdysis in 5th instar and prepupal stages each but 1 day after ecdysis in pupal stage. Also, optimum pH of midgut protease is pH 8.0 in 5th instar stage, pH 6.5 in prepupal stage, and pH 8.5 immediately before emergence respectively. Protease is found mostly in midght tissue in 5th instar stage but thereafter until just before emergence the enzyme only in lumen contents, suggesting that protease is synthesized in midgut tissue during larval stage and then released into lumen during pupation period.