NOS and COX isoforms and abnormal microvessel responses to CO2 and H+ in hyperoxia-injured lungs

The aim of the present study was to compare microvessel responses to hypercapnic and isocapnic acidosis in hyperoxia-injured lungs and to assess the role of constitutive and inducible forms of nitric oxide synthase (NOS) and cyclo-oxygenase (COX). Real-time confocal luminescence microscopy was used to measure changes in the diameter of acinar arterioles, venules and capillaries in response to stimulation with hypercapnic and isocapnic acidosis in isolated rat lungs injured by 90% oxygen exposure for 48 h. Observations were made with and without inhibition of constitutive (endothelial constitutive NOS (ecNOS) and COX-1) and inducible isoforms (iNOS and COX-2) of NOS and COX. Upregulation of NOS was assessed by measuring enzyme levels in lung homogenates by Western blot analysis and enhancement of the COX-related pathway was judged from perfusate concentrations of 6-ketoprostaglandin F1alpha. ecNOS and COX-1, but not iNOS and COX-2, were upregulated in hyperoxia-injured lungs. The nitric oxide produced by ecNOS attenuated COX-1 activity in injured arterioles and venules, but carbon dioxide enhanced it, leading to paradoxical dilatation of these microvessels under hypercapnic conditions with ecNOS inhibition. Although a high hydrogen ion concentration was unnecessary for excitation of COX-1, venule constriction in response to H+ was enhanced by COX-1 inhibition. Constitutive, but not inducible, isoforms of cyclo-oxygenase and nitric oxide synthase play an important role in abnormal microvessel responses to carbon dioxide and hydrogen ions in hyperoxia-injured lungs.

Disorganization of honey-comb immunoreactive pattern of desmin and plectin in rat atrophic soleus muscle fiber induced by hindlimb suspension

Immunoreactivity for desmin, plectin and alpha-actinin was investigated in rat atrophic soleus muscle fibers induced by hindlimb suspension between 1 and 4 weeks (hindlimb suspension group, HSG), and compared with that of the control group (CG). Some of the HSG for 4 weeks were allowed unrestricted cage activity for 2 weeks as the recovery group (RG). In the cross-sectioned muscle fibers of the CG, desmin and plectin showed honey-comb immunoreactive patterns extending throughout the sarcoplasm. Superimposed images by double immunofluorescence labeling showed overlapping of both immunoreactivities. In the longitudinally sectioned profiles, superimposed images of alpha-actinin and desmin were overlapped at the level of Z-discs. The focal disorganization of the above honeycomb immunoreactive patterns, followed by the reduction of the cross-sectional area (CSA) of atrophic soleus muscle fibers and the appearance of Z-streaming, uniquely arose in the HSG from the first week and extended throughout the sarcoplasm in proportion to the suspension period. Such honey-comb patterns of both desmin and plectin were already restored in the RG at 2 weeks, followed by the disappearance of Z-streaming, prior to the recovery of the CSA. These findings indicate that the disorganization of topological and structural relationships of desmin and plectin with Z-discs surrounding individual myofibrils is primarily evoked, which leads to Z-streaming of atrophic soleus muscle fibers, and that the restoration of the muscle activity results in an early arrangement recovery of desmin and plectin around myofibrils.

Secretory carcinoma of the breast: a tumour analogous to salivary gland acinic cell carcinoma?

AIMS

Acinic cell-like breast carcinoma is a newly recognized entity, and few acinic cell-like breast carcinoma cases have been reported. All reported acinic cell-like breast carcinomas were counterparts of the solid type of acinic cell carcinoma of the salivary gland. We report here three cases of secretory breast carcinoma with acinic cell differentiation, and discuss the similarity between secretory breast carcinoma and acinic cell carcinoma of the salivary gland.

METHODS AND RESULTS

The cases were histologically identical to acinic cell carcinoma of the salivary gland: papillary-cystic type in case 1, a mixture of papillary-cystic, microcystic and follicular type in case 2, and microfollicular type in case 3. Immunohistochemically, the tumour cells were positive for salivary-type amylase, lysozyme, S100 protein and alpha 1-antitrypsin, and negative or less reactive for gross cystic disease fluid protein-15 and oestrogen receptor. All three cases did not reveal metastasis or recurrence.

CONCLUSIONS

These cases were typical of secretory breast carcinoma, and were clinically, histologically and immunohistochemically analogous to acinic cell carcinoma of the salivary gland. We emphasize that secretory breast carcinoma and acinic cell carcinoma of the salivary gland may be identical lesions.

Biopsy pathology predicts patients with ulcerative colitis subsequently requiring surgery

BACKGROUND

The clinical course of patients with ulcerative colitis (UC) is unpredictable, and 17%-38% ultimately require surgery. We hypothesized that mucosal histology may differ between patients requiring surgery and those receiving medication alone. The aim of this study was to elucidate comprehensive criteria consisting of specific histologic features enabling the prediction of failure to medical treatment.

METHODS

We studied colorectal biopsy specimens from 67 patients ultimately requiring surgery (UC-S) and 90 receiving medication alone for more than 3 years (UC-M), and conducted multiple logistic regression analysis on 70 histologic features together with endoscopic disease extent and patient age. The analysis constructed an equation finding probability of UC-S (P(UC-S)). Based on a receiver-operating characteristic curve, we selected four cut-off values of P(UC-S), and determined criteria of five categories: highest-risk, higher-risk, unpredictable, lower-risk and lowest-risk of surgery. Sensitivity and specificity of criteria were evaluated in a 2 x 5 table.

RESULTS

Statistically significant features predicting UC-S were deep ulceration (X1), frequent crypt abscesses (X2), focal and segmental mononuclear cell infiltration (X3 and X4), paucity of eosinophils (X5: eosinophil infiltration) and wide extent of the disease (X6). The regression equation was as follows: logitP(UC-S) = -16.26 + 3.20X1 + 4.83X2 + 11.65X3 + 5. 10X4 - 5.59X5 + 5.53X6. Higher-risk and lower-risk showed sensitivity exceeding 91.0% and specificity exceeding 98.5% in predicting the outcome.

CONCLUSIONS

Our criteria incorporating specific histologic features and endoscopic disease extent reliably predict eventual clinical outcome, and are expected to prove useful in determining the necessity of surgery.

Enhanced expression of endothelin-1 and endothelin-converting enzyme-1 in acute hypoxic rat aorta

Deeply anesthetized male Wistar rats were perfused by Hanks' balanced salt solution bubbled with either 95%air and 5%CO2 (normoxic group) or 95%N2 and 5%CO2 (hypoxic group) from the thoracic aorta for 30 min, and the isolated abdominal aortae from both groups were used for electron microscopy, immunocytochemistry of endothelin (ET)-1 and ET-converting enzyme (ECE)-1, and in situ hybridization of preproET-1 mRNA. A remarkable increase in the number of Weibel-Palade (WP) bodies, storage sites of ET-1 and ECE-1, occurred in the hypoxic group when compared to the normoxic group. Immunoreactivities for ET-1 and ECE-1, and signals for preproET-1 mRNA were seen along the endothelia of both groups, but the intensities were significantly elevated in the hypoxic group. The increase in the number of ECE-1 immunoreactive gold particles was noticed especially in WP bodies in the hypoxic group. These findings indicate the enhancement of preproET-1 synthesis in the aortic endothelial cells as well as the acceleration of ET-1 processing in increased WP bodies in such cells in an experimentally hypoxic condition of the rat aortae.

Observer variation of diagnoses based on simple biopsy criteria differentiating among Crohn's disease, ulcerative colitis, and other forms of colitis

BACKGROUND AND AIM

Simple mucosal biopsy criteria proposed by authors reliably differentiate idiopathic inflammatory bowel disease (IBD) from other forms of colitis (non-IBD) and Crohn's disease involving the colon (CD) from ulcerative colitis (UC). The aim of this study is to investigate the reproducibility of these criteria.

METHODS

Three established pathologists and two medical students blindly examined 20 sets of multiple biopsy slides from patients with CD, 20 from those with UC, and 20 from those with non-IBD. The students had been given instructions on histological definitions using another 15 sets previously. Each observer evaluated 10 histological items required in the criteria and determined categorical diagnoses such as definite IBD and probable UC. Interobserver agreement for the individual histological items was measured by using kappa analysis and Pearson's correlation, while it was measured for categorical diagnoses with the use of Spearman's rank correlation.

RESULTS

All of the individual histological items expressed excellent or fair-to-good agreement among the five observers, although two items associated with the criteria for CD and UC had poor agreements among the students. With regard to categorical diagnoses based on the criteria for IBD and non-IBD, and those for CD and UC, coefficients for Spearman's rank correlation exceeded 0.92 and 0.86 among the pathologists, and 0.76 and 0.74 among the students, respectively; all of the coefficients were statistically significant (P < 0.05).

CONCLUSIONS

The simple criteria were sufficiently reproducible and would help most pathologists to make an automated and objective diagnosis.

Spatial distribution and histogenesis of colorectal Paneth cell metaplasia in idiopathic inflammatory bowel disease

BACKGROUND AND AIM

Colorectal Paneth cell metaplasia (PCM) is known to be a sign of idiopathic inflammatory bowel disease (IBD), although its distribution and histogenesis are not fully understood. Objectives of this research were to investigate the spatial distribution of PCM in IBD and other forms of colitis (non-IBD), and to find stimuli causing PCM.

METHODS

We studied multiple biopsy specimens from 181 patients with ulcerative colitis (UC), 159 with Crohn's disease (CD), 448 with non-IBD, and 78 normal controls. Paneth cell metaplasia frequency, at each colorectal site, was evaluated to find possible differences among diseases, phases of activity, and extents of disease.

RESULTS

In non-IBD and controls, PCM was rarely (0-1.9%) seen at distal sites, but frequently (up to 48.7%) found at the ascending colon and cecum (P < 0.001). Paneth cell metaplasia frequency was significantly higher in IBD than in non-IBD patients and controls at distal sites (P < 0.001), but did not differ significantly between UC and CD, or among active, resolving, and quiescent phases. In UC, proctitis and left-sided colitis rarely displayed PCM at unaffected sites. Multiple logistic regression analysis revealed that PCM was positively associated with crypt distortion and mononuclear cell infiltration (P < 0.005), but negatively or not significantly associated with crypt atrophy, mucin depletion, acute inflammation, or phase of activity.

CONCLUSIONS

Paneth cell metaplasia is a non-specific phenomenon in the proximal colon, but distal PCM, which occurs exclusively in affected mucosa, is a useful marker indicating IBD, even in the inactive phase. Regression analysis suggests that repair and regeneration may be the most potent stimuli causing PCM.

Rebinning-based algorithms for helical cone-beam CT

Several image reconstruction algorithms based on rebinning have been proposed recently for helical cone-beam CT. These algorithms separate the 3D reconstruction into a set of independent 2D reconstructions for a set of surfaces: planar or non-planar surfaces are defined and then reconstructed using 2D filtered backprojection from a 2D fan-beam or parallel-beam set of data estimated from the cone-beam (CB) measurements. The first part of this paper presents a unified derivation of rebinning algorithms for planar and non-planar surfaces. An integral equation is derived for the surface allowing the best rebinning and an iterative algorithm converging to the solution of that equation is given. The second part presents an efficient method to correct the residual reconstruction artefacts observed with rebinning algorithms when the cone-angle is too large for the required accuracy. This correction algorithm involves a CB backprojection and the reconstruction time is slightly longer than for the zero-boundary (ZB) method.

Kudo total elbow arthroplasty in patients with rheumatoid arthritis: a long-term follow-up study

BACKGROUND

Improvements in the design of total elbow prostheses over the last two decades have led to better and more consistent results. The type-3 Kudo total elbow prosthesis was developed in 1980. The long-term results of use of this implant have not been reported. Because it is an unlinked prosthesis, it is not known whether preservation of the anterior oblique component of the ulnar collateral ligament at the time of implantation is important.

METHODS

A type-3 Kudo total elbow arthroplasty with cement was performed in forty-seven patients (fifty elbows) with rheumatoid arthritis. Revision rates, clinical symptoms, postoperative complications, and radiographic changes were assessed eleven to sixteen years (mean, thirteen years) postoperatively.

RESULTS

The overall survival rate of the prosthesis was 90% at sixteen years. The mean Mayo elbow performance scores were all poor (mean overall score, 43 points) initially. The overall score was substantially improved at both the intermediate follow-up examination (four to six years after the operation) and the late follow-up examination (eleven to sixteen years after the operation), to 81 and 77 points, respectively. The overall rate of radiolucency about the humeral component was 45% at the intermediate follow-up examination and 100% at the long-term follow-up examination. The rate of radiolucency about the ulnar component at the intermediate and late follow-up examinations was 4.3% and 8.9%, respectively. No great differences in results were found with preservation of the anterior oblique component of the ulnar collateral ligament.

CONCLUSIONS

This long-term follow-up study showed acceptable results of the type-3 Kudo total elbow arthroplasty in patients with rheumatoid arthritis. Preservation of the ulnar collateral ligament does not seem to be necessary when performing this procedure.

Synthesis of calcitonin gene-related peptide (CGRP) by rat arterial endothelial cells

We investigated the protein and mRNA expression of calcitonin gene-related peptide (CGRP) in endothelial cells of the rat thoracic aorta and femoral artery. Light microscopic immunocytochemistry revealed that immunoreactivity for CGRP was preferentially located in the endothelium of both vessels. Immunoelectron microscopy showed that CGRP-immunoreactive gold particles were preferentially localized on cisterns of the rough endoplasmic reticulum and on the Weibel-Palade (WP) bodies in the endothelial cells. Prepro CGRP mRNA signals were also detected on the endothelium. Our results are the first to demonstrate that endothelial cells of both elastic and large muscular arteries synthesize CGRP and store it, in part, in WP bodies, implying that CGRP may act as an endothelium-derived relaxing factor in these vessels.

[A case of chronic erosive polyarthritis which developed 14 years after an intestinal bypass operation with subsequent remission by intestinal revision]

A 38-year-old female patient developed the symptoms and signs of arthritis in the right tarsal joint for the first time after 14 asymptomatic years following an ileo-colic intestinal bypass operation which had been performed as an emergency procedure for acute ileus due to intestinal adhesions caused by the previous abdominal surgery. Her arthritis took a progressively severe course thereafter, primarily involving the joints of both lower extremities, and 13 years after the onset of symptoms she still continued to have active polyarthritis. However, no concomitant skin lesions of any form had been recognized throughout the course of the arthritis. On the articular radiographs erosive changes were evident in the right tarsal joints and also in the MTP joints of both big toes. Laboratory examinations of the serum revealed negative results for rheumatoid factor, circulating immune-complexes, anti-nuclear antibodies, and anti-DNA antibodies, while the serum level of CRP as well as the erythrocyte sedimentation rate were elevated. Other routine laboratory tests were all unremarkable, and neither HLA-B 27 nor HLA-DR 4 were positive. Therapeutic drug regimens consisting of NSAIDs, oral as well as intraarticular steroids, DMARDs, methotrexate, and combinations of these drugs were unsuccessful in controlling the severe symptoms of the arthritis. In view of this, a revision operation of intestinal bypass was performed 13 years after the onset of the arthritis. After the revision the severe pain of the arthritis began to subside gradually, and 1 year and 6 months later the patient achieved complete remission of the arthritis, and her CRP and ESR values returned to normal.

Splenomegaly induced by recombinant human granulocyte-colony stimulating factor in rats

Spontaneous ruptures of the spleen have been observed in donors and patients with malignancy during mobilization of peripheral blood stem cells. Thus, we investigated the morphological and histological alteration of the spleen, and mRNA expression levels and activities of the DNA-synthesizing enzymes thymidylate synthase (TS) and thymidine kinase (TK) in the splenic cells, of rats treated with recombinant human granulocyte-colony stimulating factor (rhG-CSF). Daily injections of rhG-CSF for 5 or 7 days slightly enhanced the splenic weight. Single or 3-day treatment with rhG-CSF markedly enhanced the number of granulocytes in peripheral blood. Expression levels of TS and TK mRNA in the splenic cells were significantly increased 6 hours after rhG-CSF treatment. Early expression of TS and TK mRNA in the splenic cells may indicate a reseeding of hematopoietic cells from the bone marrow. Daily injections with rhG-CSF enhanced the TS and TK activities in the splenic cells. As continuous elevations of DNA-synthesizing enzyme activity and spleno-megaly are suggestive of a possible splenic rupture, the monitoring of peripheral granulocytes and splenic size is necessary during the rhG-CSF treatment.

Non-neoplastic glandular structures in a benign peripheral nerve sheath tumor

It is a recognized fact that glandular structures sometimes occur in peripheral nerve sheath tumors (PNST). Reports indicate that epithelial potential could be expressed in malignant PNST, while the glands in most benign PNST could be trapped skin adnexa. We present a case of spindle cell tumor with glandular structures. The patient was a 55-year-old man who had a subcutaneous tumor excised. The spindle cell tumor had histological characteristics of neurofibroma. The glandular structures had a pattern of immunohistochemical staining that was similar to that of the secretory coils and excretory ducts of normal eccrine glands. Therefore, the glands were thought to be naturally existing eccrine glands. The glands were completely enclosed within the tumor and not connected to one another; a cluster formation was not observed. The upper portion of tumor included some glands of skin adnexa. The spindle cell tumor may have originated from the nerves distributed around the skin adnexa, and grown to the subcutaneous tissue. The glands may have been left behind rather than have been trapped in the tumor.

Effects of hypercapnia and hypocapnia on [Ca2+]i mobilization in human pulmonary artery endothelial cells

The hydrogen ion is an important factor in the alteration of vascular tone in pulmonary circulation. Endothelial cells modulate vascular tone by producing vasoactive substances such as prostacyclin (PGI2) through a process depending on intracellular Ca2+ concentration ([Ca2+]i). We studied the influence of CO2-related pH changes on [Ca2+]i and PGI2 production in human pulmonary artery endothelial cells (HPAECs). Hypercapnic acidosis appreciably increased [Ca2+]i from 112 +/- 24 to 157 +/- 38 nmol/l. Intracellular acidification at a normal extracellular pH increased [Ca2+]i comparable to that observed during hypercapnic acidosis. The hypercapnia-induced increase in [Ca2+]i was unchanged by the removal of Ca2+ from the extracellular medium or by the depletion of thapsigargin-sensitive intracellular Ca2+ stores. Hypercapnic acidosis may thus release Ca2+ from pH-sensitive but thapsigargin-insensitive intracellular Ca2+ stores. Hypocapnic alkalosis caused a fivefold increase in [Ca2+]i compared with hypercapnic acidosis. Intracellular alkalinization at a normal extracellular pH did not affect [Ca2+]i. The hypocapnia-evoked increase in [Ca2+]i was decreased from 242 +/- 56 to 50 +/- 32 nmol/l by the removal of extracellular Ca2+. The main mechanism affecting the hypocapnia-dependent [Ca2+]i increase was thought to be the augmented influx of extracellular Ca2+ mediated by extracellular alkalosis. Hypercapnic acidosis caused little change in PGI2 production, but hypocapnic alkalosis increased it markedly. In conclusion, both hypercapnic acidosis and hypocapnic alkalosis increase [Ca2+]i in HPAECs, but the mechanisms and pathophysiological significance of these increases may differ qualitatively.

A murine osteosarcoma cell line with a potential to develop ossification upon transplantation

An osteosarcoma cell line has been established from a soft tissue tumor that occurred spontaneously in a BALB / c mouse. This cell line showed ossification when transplanted into syngeneic mice. To examine the mechanism of bone formation, the expression of mRNAs for osteoblastic and chondroblastic markers and factors associated with ossification has been investigated. In culture, the cells exhibited a spindle shape in the growth phase, but had a polygonal shape in the stationary phase. Reverse transcription-polymerase chain reaction analysis showed that the cells expressed mRNAs for pro-alpha1(I) chain of type I collagen, alkaline phosphatase, osteopontin, osteocalcin, and core binding factor alpha1, suggesting differentiation into the stage of osteoblasts during the stationary phase. After transplantation, histological examination revealed small foci of pale blue material and basophilic networks that were scattered in the tumor tissues at one week. The former stained positive with alcian blue, suggesting a chondroid matrix. Pro-alpha1(II) chain of type II collagen mRNA was expressed at one week. A large part of tumors at two and three weeks consisted of basophilic networks, which stained positive via von Kossa's method, indicating a calcified woven bone. In situ hybridization analysis showed strong expression of osteopontin and osteocalcin mRNAs in tumor cells surrounding the bone matrix. Bone morphogenetic protein-6 and -7 mRNAs were detected in transplanted tumors, but not in cultured cells. These results suggest that the cell line has the properties of an osteoblastic lineage when cultured in vitro and has an ossifying ability through endochondral bone formation processes when transplanted in vivo.

Colonic intra-epithelial carcinoma occurring in a hyperplastic polyp via a serrated adenoma

We present a case of intra-epithelial carcinoma occurring in a serrated adenoma of the colon. The pedunculated polyp, which measured 12 x 10 x 6 mm, was endoscopically removed from the ascending colon of a 78-year-old woman. Histologically, the polyp mainly consisted of serrated adenomatous glands, and had foci of intra-epithelial carcinoma at the top. Hyperplastic (metaplastic) areas were also present in both borders between the serrated adenomatous area and the surrounding normal mucosa. A sequential increase in the degree of dysplasia, and in the number of nuclei positively reactive for Ki-67 and p53 was evident from the hyperplastic areas toward the foci of carcinoma. The polyp described here may represent a carcinogenic potential of hyperplastic polyp via serrated adenoma.