Ultrastructure of cecal endocrine cells in normal mice and mice with experimental escherichiosis

Laboratory of Infectious Pathology, Research Institute of Human Morphology, Russian Academy of Medical Sciences, Moscow. (Presented by Academician of the Russian Academy of Medical Sciences N. K. Permyakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 10, pp. 429–432, October, 1992.     

Morphologic and functional characteristics of the cecum in experimental influenza

Laboratory of Infectious Pathology, Research Institute of Human Morphology, Russian Academy of Medical Sciences, Moscow. (Presented by Academician of the Russian Academy of Medical Sciences N. K. Permyakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 10, pp. 416–419, October, 1992.     

Epithelial cell dynamics in rabbit cecum and proximal colon P1

The large intestine of mammals has long been viewed as an osmoregulatory organ, and evidence suggests that fluid and solute transport mechanisms within the intestine are heterogenous, varying depending on the particular segment involved. Variations in function are often matched by morphological correlates, but despite the widespread use of rabbit large intestine as an experimental model, there is a lack of knowledge about the cellular makeup and dynamics in the colonic mucosal epithelium. The presence of mitotic figures and immunohistochemical localization of proliferating cell nuclear antigen (PCNA) were used to identify the proliferative zone(s). Cellular migration patterns were determined through the use of the thymidine analog 5‐bromo‐2‐deoxyuridine (BrdU) over a 24‐, 48‐, and 72‐hr period. Apoptotic nuclei were identified utilizing terminal deoxynucleotidyl transferase d‐UTP nick‐end labeling (TUNEL). Both cecum and the initial portion of the proximal colon (P1) exhibited a proliferative zone at or near the crypt base, and migration proceeded upwards toward the surface epithelium lining the intestinal lumen, where apoptosis occurred Turnover time of crypt columnar cells was determined to be about 3 days; that of mucous cells was estimated to be about 5 weeks. Rabbit cecum and proximal colon P1 are similar in their cellular morphology and epithelial cell kinetics. In both, the major proliferative zone is located at or near the crypt base, from which crypt columnar cells migrate toward the lumenal surface epithelium over a period of 3 days. Goblet cell turnover rate is much slower than that of columnar cells. Anat Rec 264:427–437, 2001. © 2001 Wiley‐Liss, Inc.     

Heparin and mast cells in the course of experimental extrahepatic cholestasis

The blood heparin concentration and the number of mast cells in the tissues were studied in rats at various times after ligation of the common bile duct. The blood heparin level rose during cholestasis. The total number of mast cells was slightly reduced on the third day, increased on the seventh day, and back to normal on the 14th day. The ratio between granulated and degranulated forms of cells was sharply altered in favor of the latter. Changes in the number of mast cells and the increase in the number of degranulated forms are regarded as the result of irritation of mast cells by bile acids and pigments which accumulate in the body.Department of Pathological Physiology and Department of Pathological Anatomy, I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 4, pp. 407–409, April, 1976.     

Characteristics of the chicken proximal cecum hexose transport system

The properties of the sugar transport system present in chicken proximal cecum have been studied and compared to the jejunal transport system. Experiments were carried out in isolated enterocytes from 5- to 7-weak-old birds. Results show that: (1) Cecal cells are capable of high sugar transport rates by a phloridzin-sensitive mechanism. After 60 min incubation, the accumulation ratio (control/phloridzin-incubated cells) for 0.1 mmol/l -methyl-d-glucoside (-MG) was 43 and that of 3-oxy-methyl-d-glucose (3-OMG) was 25. In jejunal cells, ratios were 37 for -MG and 13 for 3-OMG. The differences found in cumulative capacity of 3-OMG between cecal and jejunal cells suggest that the sodium-independent pathway offers a very small contribution to sugar efflux in the steady-state in the former cells. (2) Lowering external Na⁺ concentration reduces the steady-state -MG accumulation in cecal cells (as in jejunal cells), indicating that the transport system is Na⁺-dependent. (3) The process depends on the electrochemical Na⁺ gradient across the cell membrane since both 2,4-dinitrophenol (0.2 mmol/l) and ouabain (0.25 mmol/l) abolish sugar accumulation. (4) Addition of 10 mmol/l 3-OMG to the incubation medium markedly reduces the uptake of -MG (concentration: 0.1 mmol/l), indicating that the cecal transport system can be inhibited by analogues of the transported substrate. (5) The specific sugar transport process is a saturable function of -MG concentration, the apparentK _m being 1.02 mmol/l andV _m 10.7 nmol/mg cell protein · min. Kinetic constants in jejunal enterocytes were 1.58 mmol/l (K _m) and 24.7 nmol/mg cell protein · min (V _m), respectively. In brief, the proximal cecal epithelium has a sugar transport system with properties similar to those of the jejunum which suggests a role of this epithelium in the absorption of hexoses of either ileal or cecal origin.     

Relation between α-methyl-D-glucoside influx and brush border surface area in enterocytes from chicken cecum and jejunum

We have investigated the possible relation between the phloridzin-sensitive influx of -methyl-D-glucoside (concentration 5 mmol/l) and the brush border surface area, in chicken isolated enterocytes. The intestinal regions studied were: jejunum and proximal cecum (both with high affinity sugar transport sites), medial cecum (with a low affinity transport system) and distal cecum (which lacks any transport ability). Cell apical surface measured by electron microscopy gave the following results; jejunal cells (0.41 m²) >proximal cecal cells (0.23 m²)>medial cecal cells (0.15 m²)=distal cecal cells (0.14 m²). This parameter is mainly determined by the length of microvilli. Sugar influx studies showed that the concentration of the substrate in cell water (in mmol/l) was jejunum (7.1)>proximal cecum (2.9) >medial cecum (1.7)>distal cecum (not different from zero). The decline in influx rate from proximal to distal cecum may be explained both by changes in surface and by the different carriers involved (differentK _m). Results of sugar concentration in the distal cecal cells do not correlate with the other segments studied since the substrate enters in these cells by a passive process. It is concluded that the degree of development of microvilli should be taken into account when estimating nutrient transport rates in different intestinal segments.     

Plasmablastic lymphoma of the cecum: Report of a case with cytologic findings

Plasmablastic lymphoma (PBL) is a rare lymphoma that is characterized by a diffuse proliferation of large neoplastic cells resembling B immunoblasts, but shows the immunophenotype of plasma cells. PBL is most commonly seen in the oral cavity of human immunodeficiency virus (HIV)‐positive patients. Epstein‐Barr virus (EBV) may be closely related the pathogenesis of PBL. We report a case of HIV‐negative PBL in a 75‐year‐old man without EBV infection. Histologic examination of the cecal tumor following right hemicolectomy and cytologic examination of ascitic fluid were performed. Cytologic specimens were hypercellular and composed of single cells and loosely formed clusters. Large tumor cells showed plasmacytoid features with basophilic cytoplasm, large nuclei, prominent nucleoli, and focal perinuclear halos. Abnormal mitotic figures were easily identified. On immnohistologic study, the tumor cells were positive for CD138 (plasma cell marker) and kappa, but negative for CD45, CD3, CD20, CD79a, CD56, and cyclin D1. The proliferation index (Ki‐67) was high. This is a very rare case of PBL without HIV and EBV infection, involving the cecum. Diagn. Cytopathol. 2011;39:297–300. © 2010 Wiley‐Liss, Inc.     

Mast cells and inflammatory mediators in chronic ulcerative colitis

Chronic ulcerative colitis (CUC) is an inflammatory destructive disease of the large intestine characterized by motility and secretion disorders. In the past decade, attention has been paid to the role of neuronal structures and mast cells in regulating inflammatory and immune responses in inflammatory bowel disease (IBD). The present study was performed to demonstrate neuronal fibres (NF) and cells containing substance P (SP), tryptase and serotonin (SER) in the colonic wall of patients with CUC in remission. Biopsy specimens of 6 patients with CUC were investigated with immunocytochemical methods. Normal colon tissue obtained from 6 patients with rectal carcinoma was used as a control. An increased number of SP- and SER-positive NF was found in all the layers of the intestinal wall. The number of SER-containing endocrine cells in the mucosal glands was also increased per crypt. Tryptase-, SP- and SER-immunopositive mast cells were found in higher amounts than in control specimens in close apposition to the basal lamina of the glands among the epithelial cells and in other layers of the gut wall. Two types of mast cells were found: mast cells containing both tryptase and SP, and mast cells containing tryptase only. It is concluded that interactions between neuronal elements and mast cells play a significant role in the progress and maintenance of inflammatory processes in CUC.     

用人盲肠未分化腺癌细胞系建立的裸鼠移植瘤模型及其生物学特性

作者用人盲肠未分化腺癌体外培养细胞系移植于裸小鼠皮下获得裸鼠可移植瘤模型,定名为NB-93。现已传至第26代。移植成功率为96.2%。裸鼠带瘤生存时间最长者为246天,中位数为108天。裸鼠移植瘤病理组织学的结构与原始人体肿瘤的形态相似。移植瘤具有分泌CEA的能力。染色体分析显示了人类恶性肿瘤染色体特征。移植瘤组织经液氮冻存再复苏后,可移植性不变。该移植瘤裸小鼠模型的建立,为进一步研究人盲肠未分化腺癌提供了有用的手段。     

Ultrastructure of the duodenal epithelial cells in the early stages of experimental colibacillosis

Laboratory of Infectious Pathology, Research Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. K. Permyakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 1, pp. 78–82, January, 1990.     

Correlation between mast-cell and leukocytic activity and permeability of mesenteric venules in rats with experimental peritonitis

Department of Electron Microscopy and the Microcirculation, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 5, pp. 544–547, May, 1991.