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Diaphragm disease after use of nonsteroidal anti-inflammatory agents: first report of diagnosis with capsule endoscopy.

Diaphragm disease of the small intestine is part of the spectrum of diseases associated with injury to the gastrointestinal tract induced by nonsteroidal anti-inflammatory drugs. Standard endoscopy or contrast studies of the small intestine rarely identify these lesions. The diagnosis usually is established at the time of surgery. We report the case of a 72-year-old woman with obscure gastrointestinal bleeding and intermittent obstruction of the small intestine who had had multiple hospitalizations and extensive testing. The patient had been treated with nonsteroidal anti-inflammatory drugs for osteoarthritis. A radiograph of the small intestine with barium contrast revealed no abnormalities, so capsule endoscopy was performed. Capsule endoscopy showed multiple small intestinal strictures beyond which the capsule could not pass. After the patient experienced continued symptoms suggestive of intermittent partial obstruction of the small intestine, computed tomography showed the capsule within a dilated loop of intestine adjacent to a stricture. After 9 days of conservative medical therapy and worsening symptoms, the patient required an exploratory laparotomy. The capsule was located in a 12-cm segment of intestine with 4 diaphragm-like lesions. Pathologic study found submucosal lesions with features identical to those of neuromuscular and vascular hamartoma (eg, mature, reactive tissue elements of smooth muscle, dense fibrous tissue, and nerve tissue bundles with scattered ganglion cells and vessels). No manifestations of Crohn disease were evident. This case represents the first diagnosis with capsule endoscopy of diaphragm disease of the small intestine with pathologic features of neuromuscular and vascular hamartoma.

Aged↗

Osteoprotegerin in the inner ear may inhibit bone remodeling in the otic capsule.

OBJECTIVES: To elucidate factors that may be responsible for the inhibition of remodeling of bone within the otic capsule. METHODS: Expression of osteoprotegerin (OPG), receptor activator of nuclear factor kappa B (RANK), and RANK ligand (RANKL) were assayed in samples of bone obtained from the otic capsule, calvarium, and femur, and from the soft tissue within the cochlea using semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) in mice. Immunostaining was used for histologic localization of the gene products. An enzyme-linked immunosorbent assay (ELISA) was used to quantify the amount of OPG within perilymph, serum, and cerebrospinal fluid. The micro-anatomy of the interface between the otic capsule and the fluid spaces of the cochlea was investigated by brightfield and phase-contrast microscopy and by three-dimensional reconstruction in the mouse and human. RESULTS: OPG, a powerful inhibitor of bone remodeling, was expressed at extremely high levels within the soft tissue of the cochlea and was present in the perilymph at very high concentrations. The OPG produced within the inner ear may diffuse into the surrounding otic capsule, where it may be responsible for inhibition of bone turnover. Our anatomic studies revealed an extensive system of interconnected canaliculi within the otic capsule that had direct openings into the fluid spaces of the inner ear, thus providing a possible anatomic route for the diffusion of OPG from the inner ear into the surrounding bone. CONCLUSION: OPG, a potent inhibitor of osteoclast formation and function, is expressed at high levels within the inner ear and is secreted into the perilymph and the surrounding bone and may serve to inhibit active bone remodeling within the otic capsule, especially immediately adjacent to the cochlea. By this means, the cochlear soft tissue may control the nature of the surrounding petrous bone.

Animals↗

Osteoprotegrin knockout mice demonstrate abnormal remodeling of the otic capsule and progressive hearing loss.

OBJECTIVES: The otic capsule, when compared with other bones in the body, is unique in that it undergoes no significant remodeling of bone after development. We previously demonstrated that osteoprotegerin (OPG), which inhibits formation and function of osteoclasts, is produced at high levels in the inner ear of normal mice and secreted into the perilymph from where it diffuses into the surrounding otic capsule bone through a lacunocanalicular system. To test our hypothesis that the high level of OPG may be important in the inhibition of otic capsule remodeling, we studied the light microscopic histology of the otic capsule in OPG knockout mice for evidence of abnormal remodeling of bone. We also tested the hearing in OPG knockout mice to determine whether OPG and its influence on surrounding bone is important for auditory function. METHODS: Temporal bone histopathology and pathophysiology were compared in homozygous OPG knockout mice and C57BL/6 (B6) mice, the background strain for the knockouts. Auditory function in age-matched animals from each group was evaluated at approximately 4-week intervals from 8 to 21 weeks using frequency-specific auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE). After each of the last three evaluations, the cochleae from one mouse of each group were harvested, processed, and examined by light microscopy. RESULTS: Osteoprotegerin knockout mice demonstrated abnormal remodeling of bone within the otic capsule with multiple foci showing osteoclastic bone resorption and formation of new bone. Such changes were not seen in the age-matched B6 controls. The active bone remodeling process in the knockout animals showed many similarities to otosclerosis seen in human temporal bones. Over the time period that we monitored, auditory function was significantly and progressively compromised in the knockout animals relative to B6 controls. At the earliest age of test (8 wk), the loss was apparent as a mild, high-frequency reduction in sensitivity by ABR. In contrast, DPOAE losses in the knockouts were substantial even at 8 weeks, and by 21 weeks, these losses exceeded our equipment limits. Results of ABR testing showed hearing sensitivity changes in the animals of the background strain were confined largely to the high frequencies, whereas OPG knockouts demonstrated substantial low-frequency shifts in addition to those at high frequencies. CONCLUSIONS: The histopathological and pathophysiological findings in OPG knockout mice support the hypothesis that OPG is important in the inhibition of bone remodeling within the otic capsule and the maintenance of normal auditory function. This mouse may provide a valuable animal model of human otosclerosis.

Acoustic Stimulation↗

Video capsule endoscopy of the small bowel (PillCam SB).

PURPOSE OF REVIEW: It is 4 years since capsule endoscopy was first introduced. This disposable 27 mm x 11 mm video capsule containing its own optical dome, light source, batteries, transmitter and antenna is swallowed with water after a 12 h fast. The capsule is propelled via peristalsis through the gastrointestinal tract, capturing about 60 000 digital images and is excreted naturally. In a relatively short period, capsule endoscopy has become an important investigative tool in patients with occult gastrointestinal bleeding, suspected small bowel tumors and other abnormalities. The aim of this review is to update the reader with the main indications, performance and complications of the technique. RECENT FINDINGS: There are some clear indications for capsule endoscopy: occult gastrointestinal bleeding, suspected small bowel tumor, suspected Crohn's disease, surveillance of inherited polyposis syndromes, drug-induced small bowel injury or any abnormal small bowel imaging. Problematic areas include defining what are normal findings and the inability to take biopsies and thus differentiate between entities. SUMMARY: Capsule endoscopy has become a first-line tool to detect abnormalities in the small bowel, and is superior to all other imaging technologies. Its interplay with the new technique of double balloon enteroscopy enables the small bowel to receive proper attention, similar to other gastrointestinal organs.

Endoscopes, Gastrointestinal↗

Spontaneous sequence duplications within capsule genes cap8E and tts control phase variation in Streptococcus pneumoniae serotypes 8 and 37.

Capsule phase variants were isolated from serotype 8 and serotype 37 pneumococcal sorbarods. Sequence duplications within the essential capsule genes - cap8E (type 8) and tts (type 37) - were found to introduce frameshifts and generate acapsular phenotypes. Capsular revertants possessed wild-type cap8E and tts genes, indicating the precise excision of these duplications. Reversion frequencies (OFF-ON) fit a linear relationship between log(frequency of reversion) and log(length of duplication), previously found for serotype three pneumococci [Waite, R. D., Struthers, J. K. & Dowson, C. G. (2001). Mol Microbiol 42, 1223-1232]. This study provides evidence that capsule phase variation can occur in pneumococcal serotypes with either simple (one to three genes) or complex capsule-encoding loci (12 genes). Given the key role of CapE (the first monosaccharide transferase) in other clinically important pneumococci, such as serotypes 14 and 19F with complex capsular loci, the observed duplication within cap8E suggests that capsule phase variation could be controlled by tandem sequence duplication in capE homologues in other pneumococcal serotypes that construct their capsules through polymerization of lipid-linked intermediates.

Bacterial Proteins↗

Generation of isogenic K54 capsule-deficient Escherichia coli strains through TnphoA-mediated gene disruption.

Transposon mutagenesis, using IS50L::phoA(Tn-phoA), was performed in a K54/O4/H5 blood isolate of Escherichia coli (CP9), to generate a library of random mutants. Five hundred and twenty-six independent CP9 TnphoA mutants were isolated with active gene fusions to alkaline phosphatase. From this mutant library, eight capsule-deficient strains were detected and were found to have a single copy of TnphoA. Sixteen additional capsule deficient mutants with TnphoA inserts were subsequently obtained that did not possess active PhoA fusions. In conjunction with the initial eight capsule-deficient isolates we have defined genes on three different XbaI fragments as being involved in capsule production. Generalized transduction with the bacteriophage T4 established that these insertions were responsible for the loss of capsule and that they are linked. These capsule-deficient strains can be used to assess the pathogenic role of the K54 capsular polysaccharide.

Alkaline Phosphatase↗

Wireless capsule endoscopy: experience in a tropical country.

BACKGROUND AND AIM: Capsule endoscopy is fast becoming the procedure of choice for small bowel imaging, especially to investigate the cause of unexplained gastrointestinal (GI) bleeding. We report our experience with capsule endoscopy in 24 cases with various indications. METHODS: In patients with unexplained GI bleeding or chronic anemia, the cause could be established in nine of 12 cases (75%), which included angioectasiae, leiomyomata and parasitic infestation. RESULTS: The yield of capsule endoscopy was highest in patients presenting with chronic diarrhea and suspicion of small bowel mucosal disease, where Crohn's disease and tuberculosis could be diagnosed. However, in patients with unexplained abdominal pain, capsule endoscopy was found to be least useful because 5/7 patients in the study were normal, emphasizing the importance of case selection. Overall, capsule endoscopy yielded a positive diagnosis in 16 of the 24 cases (66.6%). CONCLUSIONS: The experience of capsule endoscopy in a tropical clinical setting is no different from elsewhere, although certain conditions like worm infestation are more likely to be detected in this environment.

Adolescent↗

Solitary fibrous tumor of the kidney originating from the renal capsule and fed by the renal capsular artery.

Solitary fibrous tumors (SFT) are relatively rare spindle cell neoplasms that typically arise in the pleura. Recently, extrathoracic SFT that have arisen in various anatomic sites have been recognized. The histogenesis and prognosis of SFT of the kidney are not well understood because only 11 cases have been reported. We report a case of SFT of the left kidney arising from the renal capsule. The tumor was merged with the upper pole of the left renal capsule. The angiography revealed that the renal capsule artery fed the tumor. The tumor was a well-circumscribed, solid mass attached to the renal capsule without necrosis or hemorrhage. Microscopically the bland spindle cells proliferated and were accompanied by hyalinized collagenous tissue showing patternless or hemangiopericytomatous patterns. Some glomeluri and renal tubules were entrapped by the tumor cells. There were no mitotic figures. Immunohistochemically the tumor cells were diffusely positive for CD34, CD99 and bcl-2. There was no evidence of recurrence after a 4 year follow-up visit. The origin of SFT of the kidney remains uncertain. The tumor in this case merged with the renal capsule and was fed by the renal capsular artery, which suggests that some SFT of the kidney originate from the renal capsule.

12E7 Antigen↗

Endoscopic retrieval of a capsule endoscope from a Zenker's diverticulum.

We report a case of a capsule endoscope lodged within a Zenker's diverticulum. The capsule was safely removed endoscopically. Safe re-insertion of the capsule was achieved using an overtube placed with a Savary dilator. While capsule endoscopy should be avoided in patients with large esophageal diverticula or dysphagia, this method may be used to deliver the capsule beyond the esophagus, allowing completion of the capsule endoscopy study.

Aged↗

Alteration of the Trifoliin A-Binding Capsule of Rhizobium trifolii 0403 by Enzymes Released from Clover Roots.

The effect of white clover root exudate on capsules of Rhizobium trifolii 0403 was examined. The clover lectin trifoliin A was detected in root exudate of two clover varieties by indirect immunofluorescence with antibody against this lectin purified from clover seed. Trifoliin A bound uniformly to encapsulated, heat-fixed cells during 1 h of incubation with root exudate. After 4 to 8 h of incubation, trifoliin A was only bound to one pole of the cells. Transmission electron microscopy showed that the capsule itself was altered. The disorganization of the acidic polymers of the capsule began in the equatorial center of the rod-shaped cell and then progressed toward the poles at unequal rates. Trifoliin A could no longer be detected on heat-fixed cells after 12 h of incubation with root exudate. However, trifoliin A was detected in situ on one pole of cells grown for 4 days in the clover root environment of Fahraeus slide cultures. Inhibition studies with the hapten 2-deoxy-d-glucose showed that trifoliin A in root exudate had a higher affinity for one of the cell poles. Immunoelectrophoresis was used to monitor the alteration of the extracellular polysaccharides from R. trifolii 0403 by concentrated root exudate. These polysaccharides were converted into products which eventually lost their ability to immunoprecipitate with homologous antibody. This progressive loss of antigenic reactivity proceeded more rapidly with root exudate from seedlings grown under nitrogen-free conditions than with root exudate from plants grown with 15 mM KNO(3). The root exudate, depleted of trifoliin A by immunoaffinity chromatography, was still able to alter the capsule of R. trifolii 0403. Reconstitution experiments showed that the substance(s) in root exudate which induced this alteration of the capsule was of a high molecular weight, heat labile, trypsin sensitive, and antigenically unrelated to trifoliin A. A variety of glycosidase activities were also detected in the fraction depleted of trifoliin A. These results suggest that enzymes in clover root exudate alter the trifoliin A-binding capsule in a way which would favor polar attachment of R. trifolii to clover root hairs.

Journal Article↗

Morphological evidence for penetration of anti-O antibody through the capsule of Klebsiella pneumoniae.

The role of the capsule in the reaction with anti-O or anti-K serum was examined morphologically by the techniques of freeze-substitution and immunoelectron microscopy in two strains of Klebsiella pneumoniae differing in virulence for mice. Strain Chedid (O1:K2), an encapsulated virulent strain, has a thicker capsule (150 nm) than the encapsulated avirulent strain 277 (O1:K2) (60 nm). Two morphologically recognizable domains in the capsule created by the arrangement of the capsular filaments were clearly seen in strain Chedid but were less evident in strain 277. Anti-O antibody could penetrate through the capsular layer of both strains. The capsule has no function as a barrier for the penetration of the antibody. Anti-K antibody reacted only on the surface of the capsule and induced swelling of the capsule.

Antibodies, Bacterial↗

Virulence of Staphylococcus aureus mutants altered in type 5 capsule production.

Most clinical isolates of Staphylococcus aureus produce microcapsules (uronic acid-containing extracellular polysaccharides) that are detectable by serologic methods but are not visible by negative staining. Among the 11 reported serotypes, capsule types 5 and 8 comprise approximately 75% of all isolates. Transposon mutagenesis was performed on S. aureus to create mutants altered in capsule expression. Tn918 was introduced into the capsule type 5 strain Reynolds by filter mating, and a capsule-deficient transconjugate, JL236, was isolated. The wild-type strain was transformed with JL236 chromosomal DNA to confirm that transfer of the appropriate-size chromosomal fragment containing Tn918 generated a capsule-deficient transformant. Strain Reynolds was mutagenized with ethyl methanesulfonate to obtain a capsule-negative mutant (strain JL240). Capsular phenotypes were determined by colony immunoblots, antibody adsorption experiments, and transmission electron microscopy. The virulences of the parental and mutant strains in mice were compared. The 50% lethal doses for strains Reynolds, JL236, and JL240 were similar (10(8.59), 10(8.98), and 10(8.93) CFU, respectively). Animals injected intraperitoneally with either wild-type or mutant strains had comparable levels of bacteremia at 3 and 24 h after challenge. Quantitative cultures of blood and kidneys from animals challenged intravenously with sublethal doses of the S. aureus strains also showed no differences in bacterial clearance or renal abscess formation. These studies indicate that the type 5 S. aureus microcapsule does not promote bacterial virulence in the animal models tested.

Animals↗

Protein synthesis is required for in vivo activation of polysialic acid capsule synthesis in Escherichia coli K1.

The kinetics of in vivo expression of the polysialosyl (K1) capsular antigen in Escherichia coli has been studied. Growth of E. coli K1 strains at 15 degrees C prevents K1 polysaccharide synthesis (F. A. Troy and M. A. McCloskey, J. Biol. Chem. 254:7377-7387, 1979). Synthesis is reactivated in cells grown at 15 degrees C after upshift to 37 degrees C. The early expression and resultant morphology of K1 capsular antigen was monitored in temperature upshift experiments by using electron microscopy. Morphological stabilization of the capsule was achieved by treatment of cells with an antiserum specific for the alpha, 2-8-linked polysialosyl antigen. The kinetics of K1 capsule expression in growing cells was measured by bacteriophage adsorption with phage K1F, which required the K1 capsule for binding. The results of temperature upshift experiments showed that capsule first appeared on the cell surface after 10 min. Subsequent bacteriophage binding increased linearly with time until a fully encapsulated state was reached 45 min after upshift. The initiation of K1 capsule appearance was dependent on protein synthesis and the addition of chloramphenicol before temperature upshift prevented any expression of the K1 antigen. Chloramphenicol reduced the rate of K1 synthesis when added after temperature upshift. We conclude from these results that protein synthesis is a prerequisite for activation of capsule expression in vivo, but not for subsequent elongation of polysialosyl chains.

Antibodies↗

Complementation of a capsule-deficient mutation of Cryptococcus neoformans restores its virulence.

Capsule formation plays a significant role in the pathogenicity of Cryptococcus neoformans. To study the molecular basis of capsule synthesis, the capsule-deficient phenotype of a mutant strain was complemented by transformation. A plasmid rescued from the resulting Cap+ transformant complemented a cap59 mutation which was mapped previously by classical recombination analysis. Gene deletion by homologous integration resulted in an acapsular phenotype, indicating that we have identified the CAP59 gene. The CAP59 gene was assigned to chromosome I by Southern blot analysis of contour-clamped homogeneous electric field gel electrophoresis-resolved chromosomes of C. neoformans var. neoformans. Sequence comparison of genomic and cDNA clones indicated the presence of six introns. CAP59 encoded a 1.9-kb transcript and a deduced protein of 458 amino acids. Analysis of the nucleotide sequence revealed little similarity to existing sequences in the data bank. When the capsule-deficient phenotype was complemented, the originally avirulent C. neoformans strain became virulent for mice. In addition, the acapsular strain created by gene deletion of CAP59 lost its virulence. This work demonstrates the molecular basis for capsule-related virulence and that the CAP59 gene is required for capsule formation.

Amino Acid Sequence↗

Diagnosing small bowel Crohn's disease with wireless capsule endoscopy.

BACKGROUND: The small bowel is the most commonly affected site of Crohn's disease (CD) although it may involve any part of the gastrointestinal tract. The current methodologies for examining the small bowel are x ray and endoscopy. AIMS: To evaluate, for the first time, the effectiveness of wireless capsule endoscopy in patients with suspected CD of the small bowel undetected by conventional modalities, and to determine the diagnostic yield of the M2A Given Capsule. PATIENTS: Seventeen patients (eight males, mean age 40 (15) years) with suspected CD fulfilled study entry criteria: nine had iron deficiency anaemia (mean haemoglobin 10.5 (SD 1.8) g%), eight had abdominal pain, seven had diarrhoea, and three had weight loss. Small bowel x ray and upper and lower gastrointestinal endoscopic findings were normal. Mean duration of symptoms before diagnosis was 6.3 (SD 2.2) years. METHODS: Each subject swallowed an M2A Given Capsule containing a miniature video camera, batteries, a transmitter, and an antenna. Recording time was approximately eight hours. The capsule was excreted naturally in the patient's bowel movement, and the data it contained were retrieved and interpreted the next day. RESULTS: Of the 17 study participants, 12 (70.6%, six males, mean age 34.5 (12) years) were diagnosed as having CD of the small bowel according to the findings of the M2A Given Capsule. CONCLUSIONS: Wireless capsule endoscopy diagnosed CD of the small bowel (diagnostic yield of 71%). It was demonstrated as being an effective modality for diagnosing patients with suspected CD undetected by conventional diagnostic methodologies.

Adult↗

High molecular weight caldesmon positive stromal cells in the capsule of thyroid follicular tumours and tumour-like lesions.

AIMS: To investigate the smooth muscle nature of the spindle stromal cells in the capsule of thyroid tumours and tumour-like lesions. METHODS: Immunostaining for high molecular weight caldesmon (HCD), a highly specific marker for smooth muscle differentiation, was performed in 70 primary thyroid tumours and tumour-like lesions (21 hyperplastic nodules, 29 follicular adenomas, five minimally invasive follicular carcinomas, six widely invasive follicular carcinomas, and nine encapsulated papillary carcinomas). RESULTS: HCD positive stromal cells (HCD+ cells) were detected in the capsule of 20 of the 21 hyperplastic nodules, and all of the 29 follicular adenomas and five minimally invasive follicular carcinomas, whereas HCD+ cells were seen in the capsule of only four of the six widely invasive follicular carcinomas and no HCD+ cells were seen in the capsule of the nine encapsulated papillary carcinomas examined. CONCLUSIONS: The presence of HCD+ cells in the capsule is characteristic of thyroid follicular tumours and tumour-like lesions. The stromal cells in the capsule of thyroid follicular tumours and tumour-like lesions are different from those of encapsulated papillary carcinoma.

Adenocarcinoma, Follicular↗

Subsieve-size agarose capsules enclosing ifosfamide-activating cells: a strategy toward chemotherapeutic targeting to tumors.

Localized activation of the prodrug ifosfamide in or close to tumors by implanting encapsulated ifosfamide-activating cells is an efficacious strategy for tumor therapy. The aim of this study was to evaluate the feasibility of subsieve-size agarose capsules for enclosing the cells in this application. Compared with many conventional microcapsules, subsieve-size agarose capsules are about one-tenth the size and have both higher mechanical stability and allow better molecular exchangeability than other systems. Cells that have been genetically modified to express cytochrome P450 2B1 enzyme were encapsulated in subsieve-size agarose capsules of approximately 90 microm in diameter and implanted into preformed tumors in nude mice. Living cells were detected for >1 month after encapsulation in vitro and showed enzymatic activity (i.e., they were able to activate ifosfamide). More significant regression of preformed tumors was observed in the recipients implanted with cell-enclosing capsules compared with those implanted with empty capsules. These results suggest that the strategy of using subsieve-size agarose capsules enclosing cytochrome P450 2B1-expressing cells is feasible for tumor therapy by chemotherapeutic targeting in combination with ifosfamide administration.

Animals↗

Plasma testosterone levels in adult and neonatal female rats bearing testosterone propionate-filled silicone elastomer capsules for varying periods of time.

Testosterone propionate (TP) was administered, by means of subcutaneous implanted silicone elastomer capsules, into adult and neonatal (aged 3 days) female rats. In the adult rats a dose-dependent increase in plasma testosterone was measured for capsules of three different sizes (5, 10 and 20 mm crystal length). Testosterone levels reached a peak 4-8 h after insertion (5 mm, 24.6 +/- 1.4 (S.E.M.) nmol/l; 10 mm, 34.0 +/- 3.8; 20 mm, 44.4 +/- 3.1) and returned to control levels within 4 h after removal: the calculated half-life of testosterone was 1 h for all sizes of capsule. In neonates, a capsule of 2.5 mm crystal length was removed after 4 h subcutaneous implantation (at day 3 of age) and produced peak testosterone levels of 126.2 +/- 11.8 nmol/l: the calculated half-life was 8.6 h which compared with a half-life of 48 h after a subcutaneous injection of 312 mumol TP (in 0.05 ml arachis oil) which produced peak levels of testosterone in 4-8 h of 84.6 +/- 11.8 nmol/l. Chronic implants of TP-filled capsules (2.5 mm crystal length) at 3 days of age and left in situ for 15 weeks gave a half-life of 69 h. Removable silicone elastomer capsules were found to be a versatile vehicle for the administration of TP to rats of all ages where precise hormone treatment for a known period or prolonged administration is required. The duration and magnitude of plasma hormone levels should be established by assay in an in-vivo situation.

Age Factors↗