Biomedical subjects
Publications and source records attributed to K M Das.
Four patients with retrogastric pancreatic pseudocysts were successfully treated by the combined placement of a transgastric external drain and a cystogastric stent. We describe the advantages of using external transgastric drainage along with the cystogastric stent.
Ultrasound-guided fine needle aspiration cytology (FNAC) of carcinoma of the intra-abdominal oesophagus was attempted on 21 patients with a 21 G spinal needle using a percutaneous anterior epigastric approach. The results were compared with those of endoscopic biopsy and brush cytology. The ultrasound-guided FNAC had a positive yield in 20/21 (95.2%) compared with 18/21 (85.7%) for endoscopic biopsy and 18/21 (85.7%) for brush cytology (P greater than 0.59). The combination of US-guided FNAC with endoscopic biopsy and the brush cytology achieved a positive yield in 21/21 (100%) whereas combining endoscopic biopsy and brush cytology produced a positive yield of 19/21 (90.5%). Two patients developed temporary epigastric pain. We recommend US-guided FNAC as a safe and effective technique that can be used alone or as an adjunct to endoscopic procedures for the diagnosis of carcinoma of the intra-abdominal oesophagus.
A sonographically guided anterior approach to block the coeliac plexus with local anaesthetic was attempted on supine patients before hepatobiliary interventional procedures. A satisfactory block was achieved in 8/9 patients and the minor complication of transient hypotension was encountered in two which were managed conservatively. Comparison with controls showed the coeliac block patients to require significantly less intravenous sedation and analgesia to control pain during these procedures.
The tissue distribution of a previously identified M(r) 40 K epithelial autoantigen in ulcerative colitis was examined in situ in the fetal tissue by immunocytochemical method, using an immunoglobulin M (IgM) monoclonal antibody (7E12H12). Fetal-autopsy tissue from 9 to 19 weeks of development (11-21 gestational weeks) gestations, including specimens of colon (20 specimens), skin (19), small intestine (12), gallbladder (15), liver (20), spleen (20), kidney (3), urinary bladder (3), and umbilical cord/placenta (25) were examined. 7E12H12 reactive epitope appeared first in a few colonic epithelial cells at 10 weeks of gestation. By 11 weeks, 7E12H12 reactivity was clearly evident in most of the colonic epithelial cells. Goblet-cell reactivity was evident from 15 weeks of gestation. Enterocytes lining the small intestine from all the specimens were negative. In the skin, earliest immunoreactivity was evident in the basal layer of epidermis at 10 weeks of development, and by 11 weeks, the staining was intense and localized exclusively to squamous epithelial cells of the epidermis. The immunoreactivity in the fetal gallbladder mucosa was also evident earliest at 11 weeks of development. The staining was distinct in the mucosal epithelial cells, and localized along the periphery of the cells and in the apical areas. None of the other tissue specimens reacted with 7E12H12. These results demonstrate that the 7E12H12 reactive epitope is novel, is shared by colon, skin, and biliary epithelium, and appears more or less simultaneously in the three organs at 10 to 11 weeks of development of the fetus. A possible link of this crossreactive protein or proteins in the immunopathogenesis of ulcerative colitis, sclerosing cholangitis, and pyoderma gangrenosum is discussed.
We recently reported the presence of an organ-specific 40 kD colonic protein which acts as an autoantigen(s) in patients with ulcerative colitis. Using a specific monoclonal antibody directed against 40 kD protein (7E12H12, IgM isotype), in conjunction with immunocytochemistry and flow cytometry, we examined the presence of the 40 kD protein on human colon cancer cells, DLD-1, and also characterized the ability of cytokines, IFN-gamma and tumour necrosis factor, to modulate the expression of this protein on these tumour cells. The presence of the 40 kD protein was localized to the plasma membrane; less was present within the cytoplasm. Following exposure to IFN-gamma (10-1000 U/ml), DLD-1 colon tumour cells showed a dose- and time-dependent increase in 7E12H12 antibody associated immunofluorescence, with the maximum 7E12H12 antibody binding observed with 100 U/ml IFN-gamma at 48 h. In contrast, tumour necrosis factor did not alter the levels of anti-40 kD antibody binding over that of control cells. Since IFN-gamma is also known to induce class II major histocompatibility antigens, we examined the possibility of cross-reactivity of HLA class II antigens and Mr 40 kD epitope. Neither pre-incubation of DLD-1 colon tumour cells with anti-HLA class II antibodies followed by 7E12H12 nor co-incubation of both antibodies altered the amount of 7E12H12 antibody binding. Using a direct ELISA, a highly enriched preparation of Mr 40 kD protein reactive to anti-40 kD antibody did not react with HLA class II antibodies. The present results suggest that 40 kD protein is present on DLD-1 human colon tumour cells and that although the 40 kD protein epitope expression is increased by the lymphocyte-derived cytokine, IFN-gamma, the epitope is separate and distinct from the class II HLA antigens. Further studies on the 40 KD protein may elucidate its autoantigenic role in the pathogenesis of inflammatory bowel disease.
Saguinus oedipus, Callithrix jacchus, and Saguinus fuscicollis are three species of New World monkeys which develop a form of colitis that is similar to human ulcerative colitis. Only S oedipus, however, develop colon cancer. We examined intestinal tissues from these animals for the presence of an antigen cross reacting to the Mr 40,000 human colonic epithelial protein that acts as an autoantigen in ulcerative colitis. Using an anti-Mr 40,000 monoclonal antibody (7E12H12, IgM isotype), by an immunoperoxidase assay we showed that all colon specimens from S oedipus reacted with 7E12H12; however, the colonic tissue from C jacchus and S fuscicollis did not. In immunotransblot analysis eluted IgG antibody bound to human ulcerative colitis colon (CCA-IgG) reacted with Mr 40,000 protein(s) present in the extracts of colon from S oedipus animals and humans. Small intestinal tissue reacted neither with 7E12H12 nor with CCA-IgG. In S oedipus, the Mr 40,000 protein was localised exclusively to colonic epithelial cells. Preincubation of seven S oedipus colon specimens with eight of 10 sera from animals with acute or chronic colitis and 0 of four sera from animals without colitis almost completely inhibited the binding of 7E12H12 to the colonic epithelium. Four of these 10 sera inhibited the binding of 7E12H12 to the autologous colon. These results show the presence of circulating autoantibodies in S oedipus with colitis against an epitope(s) on Mr 40,000 protein shared by human and S oedipus colon.
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Sonographically guided fine-needle aspiration cytology was performed in 19 patients suspected to have renal tuberculosis. This procedure enabled a diagnosis of renal tuberculosis to be made in six of seven patients with urine cultures consistently negative for acid-fast bacilli and confirmed the diagnosis in nine patients with focal renal lesions on sonography and urine cultures positive for acid-fast bacilli. The fine-needle aspiration cytologic samples were positive for acid-fast bacilli in seven (44%) of the 16 confirmed cases, and acid-fast bacilli were present in 80% of the samples containing necrotic material. Epithelioid granulomas were present in 15 (94%) of 16 patients diagnosed with renal tuberculosis. One patient had no evidence of acid-fast bacilli or epithelioid granulomas, but seminal fluid ultimately grew acid-fast bacilli. Two patients (13%) with evidence of tuberculosis had minor self-limiting complications from the fine-needle aspiration: one perirenal hematoma and one abdominal wall intramuscular hematoma. Sonographically guided fine-needle aspiration cytology is useful as a means of diagnosing renal tuberculosis in patients with urine cultures negative for acid-fast bacilli, and is of value in defining the granulomatous nature of sonographically visible lesions in patients with positive urine cultures.
Neuropeptides form a part of the brain-gut axis which may regulate gastrointestinal functions, including immune regulation. Various changes in the neuropeptides--most important, vasoactive intestinal peptide and substances P (VIP and SP)--have been described in inflammatory bowel disease. We employed a sensitive immunoperoxidase (avidin-biotin-peroxidase complex) technique, using anti-VIP and anti-SP antibodies to localize and compare the distribution of VIP and SP in the colon. Colon specimens from 19 normal subjects, eight patients with ulcerative colitis (UC), and eight with Crohn's disease (CD) were used. In the normal colon, VIP and SP immunoreactivity (IR) were localized in the muscularis mucosa, circular muscles, walls of blood vessels, nerve fibers, and some distinct cells, probably enterochromaffin cells. SP-IR was also present in the epithelial cells, mainly along the basolateral domain. VIP-IR was considerably diminished at all locations in patients with UC and CD. However, the SP-IR was increased in UC in the colonic epithelial cells along the basolateral areas. The SP-IR was intense in patients with CD, in the epithelium, the granulomas, cells lining the mucosal fissure, and in the muscle layers. In contrast to normals, SP-IR in patients with CD was observed both in the longitudinal and circular muscles. We conclude that VIP-IR and SP-IR are distributed widely in the mucosa, submucosa, and in the circular muscle in normal colon. VIP-IR is decreased in UC and CD, whereas SP-IR is increased in both, but more so in CD.
We studied the M. paratuberculosis-induced proliferation and suppressor cell generation by peripheral blood lymphocytes from patients with inflammatory bowel disease. Peripheral blood lymphocytes were separated from 33 patients with Crohn's disease, 18 with ulcerative colitis, nine with other intestinal diseases, and five with autoimmune disorders. Proliferation of peripheral blood lymphocytes from normal individuals in response to 10 micrograms/ml of M. paratuberculosis antigen was reduced by depletion of CD4+ T cells. The ability of M. paratuberculosis antigen to suppress concanavalin A-induced proliferation (expressed as a percentage suppression) was reduced by depletion of CD8+ T cells. This suppression was the same whether peripheral blood lymphocytes were from normal individuals, patients with intestinal diseases other than inflammatory bowel disease, or patients with autoimmune disorders (47 +/- 14%, 44 +/- 24%, and 30 +/- 26%, respectively). In contrast, the suppression induced by M. paratuberculosis for patients with Crohn's disease and ulcerative colitis (66 +/- 22% and 67 +/- 22%) was much greater than that for normal individuals (P less than 0.001). In particular, lymphocytes from patients with active Crohn's disease demonstrated little proliferation in response to this antigen but marked suppressor activity (79 +/- 13%). How the immunomodulatory effects of this antigen relate to the pathogenesis of the inflammatory bowel diseases remains to be determined.
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In patients with ulcerative colitis a colon tissue bound IgG and serum antibodies against an Mr 40,000 colonic protein(s) has been identified. Using an anti-Mr 40,000 protein monoclonal antibody, 7E12H12, by an immunocytochemical method, the protein was localised in human tissue exclusively to colonic epithelial cells. In this study the presence of the Mr 40,000 protein was assessed in experimental animals by the direct and inhibition enzyme linked immunosorbent assays (ELISAs) using the anti-Mr 40,000 protein monoclonal antibody, 7E12H12 (IgM isotype). In addition, a total of 129 specimens including colon, small intestine, gall bladder, biliary tract, and kidney from nine strains of rats and mice, and from human tissue were studied by the immunocytochemical method using 7E12H12. All colon specimens from both humans and animals reacted with 7E12H12 in the immunocytochemical and ELISA assays. None of the non-colonic organs reacted with 7E12H12. While in human colon 7E12H12 recognised the absorptive epithelial cells, in all the animals it recognised mainly the colonic goblet cells. Extracts of animal colon but not of small intestine inhibited the binding of 7E12H12 to the human colon extract. This study shows the presence of an organ specific Mr 40,000 colonic epithelial protein(s) in humans and experimental animals. A differing cellular localisation of the Mr 40,000 protein(s) in human v animal tissue was also shown. Further characterisation of the Mr 40,000 protein(s) may provide important clues regarding the autoimmune mechanisms in ulcerative colitis.
Twenty-five patients of obstructive jaundice due to choledocholithiasis, were prospectively evaluated by ultrasonography and cholangiography. Ultrasound could demonstrate choledocholithiasis in 10 patients (40%). Choledocholithiasis in non-dilated ducts could be demonstrated only in one patient. All cases were diagnosed by cholangiography. Ultrasound, though an accepted modality of choice for diagnosing cholelithiasis, has a limited role in the diagnosis of choledocholithiasis. Ultrasonography (USG) is the screening modality of choice to distinguish obstructive from non-obstructive jaundice. It is highly accurate in the diagnosis of cholelithiasis but its role in detection of choledocholithiasis is less clear. Choledocholithiasis complicates 10% of all cases of cholecystitis and occurs in 2-4% of postcholecystectomy patients. The present study deals with the diagnostic value of USG in cases of choledocholithiasis subjected to USG prior to cholangiography and surgery.
Since its introduction, prenatal diagnosis of chromosomal and metabolic disorder by midtrimester amniocentesis has relied upon the use of a mixture of fetal cells obtained from amniotic fluid. Little knowledge has been gained in the sorting of these cells for diagnosis of tissue-specific disorders. In an attempt to determine the contribution of fetal colonic mucosal cells to the overall amniocyte population, we used the colonic epithelial-specific monoclonal antibody (MC-Ab) 7E12H12, IgM isotype. Specimens of the small intestine, colon, buccal mucosa, kidney, urinary bladder, and umbilical cord were obtained from electively aborted normal fetuses of 12-28 weeks' gestation. All of these specimens were examined with 7E12H12 by the immunoperoxidase technique. The MC-Ab reacted with the colonic epithelial cells but not with any of the other tissues. In addition, 40 amniotic fluid samples obtained from women between 16 and 18 weeks of gestation, who underwent amniocentesis because of advanced maternal age, were tested using a fluorescent activated cell sorter. Among the amniotic fluid specimens examined, 18.4 +/- 10.3 per cent cells reacted with 7E12H12. Double immunofluorescence studies revealed that all Mc-Ab-stained cells contained secretory component, confirming that they were epithelial in origin. All fetuses whose amniotic fluid was analysed had normal karyotypes and amniotic fluid alpha-fetoprotein levels that were also normal. This study demonstrates that cell-specific Mc-Ab can be used to detect colon cells in the amniotic fluid and that colon cells contribute significant numbers in the mixture of amniotic fluid cells.(ABSTRACT TRUNCATED AT 250 WORDS)
We describe a modified ultrasound-guided transgastric drainage technique for pancreatic pseudocysts. Using a water-filled stomach to improve visualization, we have successfully drained pseudocysts in ten patients. This report also describes the use of a stiffening cannula to assist transgastric catheter placement. We emphasize the value of constant real-time tracking of the dilator and guidewire to ensure correct positioning of the drainage catheter.
An immune-complex-mediated inflammation has been suggested in the pathogenesis of skin and biliary complications in ulcerative colitis, although specific antigen-antibody complexes have not been found. We recently identified an Mr 40,000 colonic protein that reacts with tissue-bound immunoglobulin G eluted from colon specimens of patients with ulcerative colitis and not with immunoglobulin G eluted from colon specimens of patients with other diseases (J Clin Invest 1985;7:311). Murine monoclonal antibodies to the purified Mr 40,000 colonic protein are developed. The presence of the Mr 40,000 protein was examined with a monoclonal antibody (7E12H12, immunoglobulin M isotype) by an immunoperoxidase assay against various human epithelial tissues (74 specimens) including colon, ileum, jejunum, duodenum, stomach, esophagus, pancreaas, liver, respiratory, urinary, and genital tracts. In addition, gall bladder, bile duct, hepatic ducts, skin, synovial membrane, and eye tissue were also examined for any cross-reactivity with 7E12H12 and another anti-Mr 40,000 monoclonal antibody (7E6A5, immunoglobulin G1 isotype). 7E12H12 reacted only with colonic-epithelial cells mainly along the basolateral domains of plasma membrane and apical areas. The reactivity was present in both adult and fetal colon including the appendix. Among all the noncolonic tissue specimens, 7E12H12 reacted only with the gall bladder, the bile duct, the hepatic ducts, and the skin. All other epithelial tissues from 15 different organs, including the small intestine, synovium, and eye tissue, did not react. In the skin and biliary tract the immunoreactivity was exclusively present in the epidermal epithelial cells and mucosal epithelium respectively. 7E6A5 stained colonic mucosal cells but did not react with skin, biliary epithelium, synoyium and eye tissue. These results indicate the presence of a unique epitope or epitopes on Mr 40,000 colonic epithelial protein that is shared by the skin and biliary tract epithelial cells. Future studies of this shared epitope or epitopes and its immune recognition may provide further understanding in the pathogenesis of extraintestinal complications involving these organs in patients with ulcerative colitis.
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We have previously described a 40 kDa colonic protein(s) which is specifically recognised by tissue-bound immunoglobulin G obtained from the colon of patients with ulcerative colitis. We now report the presence of circulating antibodies against this antigen using an enzyme-linked immunosorbent assay with a highly enriched preparation of the 40 kDa protein from normal colon extracts. Serum was collected from 79 patients with ulcerative colitis, 36 with Crohn's disease, 16 with specific diarrhoeal syndromes, and from 19 normal subjects. Twenty nine of 79 patients with ulcerative colitis, 21 of 36 with Crohn's disease, and all patients with diarrhoea were symptomatic during the collection of sera. The difference in optical density values between patients with symptomatic ulcerative colitis and each of the other groups, including patients with ulcerative colitis in remission, was highly significant (p less than 0.01). Seventy nine per cent of patients with symptomatic ulcerative colitis had optical density values above the means for all other groups. Fifty five per cent of sera from patients with symptomatic ulcerative colitis had optical densities beyond two SDs of the values for all other groups and only two of 71 sera from non-ulcerative colitis patients (one Crohn's disease and one normal subject) had values in this range. These results show the presence of anti-colon antibodies against the 40 kDa protein(s) in the sera of many patients with symptomatic ulcerative colitis.