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PubMed1998

Changes in the subcellular localization of the Brn4 gene product precede mesenchymal remodeling of the otic capsule.

To better understand the genetic mechanisms that regulate the formation of the temporal bone, we have characterized the developmental expression pattern of the mouse gene, Brn4/Pou3f4, which plays a central role in bony labyrinth formation. Expression of this gene is initially detected in the ventral aspect of the otic capsule at 10.5 days post coitus (dpc), and correlates with the onset of mesenchymal condensation in the otic capsule. As the otic capsule condenses further and surrounds the entire otic vesicle, the Brn4 gene product is detected throughout the inner ear in the mesenchyme of both the cochlear and vestibular aspects. Early in otic embryogenesis, the Brn4 gene product is localized to the nucleus of the vast majority of cells in which it is expressed. The Brn4 gene product remains nuclear in those regions of the otic capsule that eventually give rise to the mature bony labyrinth. However, the subcellular localization of the Brn4 gene product shifts from strictly nuclear to perinuclear in those regions of the otic capsule that will cavitate to form acellular regions in the temporal bone, such as the scala tympani, scala vestibuli, and the internal auditory meatus. These data provide a detailed analysis of the expression pattern of the Brn4 gene, and provide insight into the role of the Brn4 gene product and its regulation during otic capsule formation.

Animals↗
PubMed2004

Evaluation of mass-transfer characteristics in alginate-membrane liquid-core capsules prepared using polyethylene glycol.

An alginate-membrane liquid-core capsule prepared using polyethylene glycol as a thickener was produced and the intracapsular mass-transfer characteristics of glucose and proteins were investigated. The apparent effective diffusivity of glucose into the capsule was 7.9x10(-10) m(2)/s, which is larger than that into alginate beads (6.5x10(-10) m(2)/s) and in water (6.7x10(-10) m(2)/s). Moreover, an encapsulation of strawberry cells did not decrease the mass transfer performance of glucose, in contrast to the case of immobilization in alginate beads or capsules prepared using xanthan gum. On the other hand, the apparent effective diffusivities of proteins from the capsule were smaller than those in alginate beads. In addition, the apparent effective diffusivities from the capsule decreased with the increasing concentration and molecular weight of polyethylene glycol used as a thickener during capsule preparation.

Journal Article↗
PubMed1990

Pathology of the otic capsule.

The otic capsule is unique in retaining calcified cartilage, known as globuli interossei, throughout life and shows changes consequently, which are peculiar to it. In Paget's disease of bone, the otic capsule appears resistant to involvement and this occurs with extensive disease at a late stage. In contrast, otosclerosis is a new bone formation of unknown cause that is limited to the otic capsule. In osteogenesis imperfecta, the poor formation of collagen leads to abnormally thin bony trabeculae with a poorly formed otic capsule. In osteopetrosis, the otic capsule is greatly expanded by increased globuli interossei, as a result of defective osteoclast function. When fractured the middle layer of the otic capsule does not form callus, but heals by fibrosis.

Bone Diseases↗
PubMed1978

Ultrastructural immunocytochemical localization of two hydatid fluid antigens (antigen 5 and antigen B) in the brood capsules and protoscoleces of ovine and equine Echinococcus granulosus and E. multilocularis.

The unlabelled antibody method was used in the ultrastructural localization of two hydatid fluid antigens, antigen 5 and antigen B, in brood capsules and protoscoleces of Echinococcus granulosus and E. multilocularis. Antigen 5 was found in the parenchyma cells of the protoscolex and brood capsule wall and to a lesser extent in the walls of the flame cells and collecting ducts of the excretory system and in the surrounding interstitial material. It is suggested that, while some excretion of this antigen may occur from the protoscolex, it could also be liberated into the cystic cavity by degeneration of protoscoleces and parenchymal cells of the brood capsule wall. Antigen B was found mainly in the distal cytoplasm and perinuclear cytoplasm of the tegument anterior to the suckers. It is apparently secreted to the outside and was present in the brood capsule contents; it adheres to the anterior surface and the posterior periodic acid-Schiff (PAS)-positive glycocalyx of the protoscolex and to the inner surface of the brood capsule wall. The protoscolex tegument posterior to the suckers was negative. The parenchyma cells of the protoscolex and brood capsule wall were also positive although the intensity of the reaction product was variable.

Animals↗
PubMed2000

Five types of nuclei present in the capsule of Trichinella spiralis.

This study describes morphological changes during capsule formation of Trichinella spiralis with emphasis on nuclei within the capsule. The nuclei of the pre-existing muscle cell may become hypertrophied or degrade soon after the entrance of newborn larvae. Cytoplasm associated with these hypertrophied nuclei was basophilic in H&E staining and composed of mitochondria and rough endoplasmic reticulum. Satellite cells underwent cell division and joined to the nurse cell. These nuclei may also become hypertrophied or degrade. Cytoplasm associated with nuclei of satellite cell origin was eosinophilic in H&E staining and composed of mitochondria, polysomes, and smooth and rough endoplasmic reticulum. Eosinophilic cytoplasm (of satellite cell origin) became prevalent in the capsule as capsule formation proceeded. Infiltrated cells were observed within the capsule. Thus this study showed diversity of nuclei in the capsule of Trichinella.

Animals↗
PubMed2001

"Flexiball" toolkit: a modular approach to self-assembling capsules.

We report the synthesis and characterization of new, self-assembling molecular capsules. The modular strategy makes use of glycoluril building blocks available in multigram amounts combined with aromatic spacer elements. The lengthy syntheses encountered with earlier generations of capsules are avoided, and several capsules of nanometer dimensions are now accessible. Single bond attachments between spacers and glycoluril modules result in monomers as dimeric capsules that are less rigid than their earlier counterparts. The host-guest properties of the homo- and heterodimeric capsules were studied using a combination of NMR and ESI-mass spectrometry. They show a less pronounced selectivity for guests of different sizes, and their increased flexibility prevents self-assembly when no rigidifying elements are present on the central spacer unit. Some of the new capsules bear inwardly directed, secondary amide N-H protons. These can be further functionalized, as shown by their methylation to give tertiary analogues. The structures hold broader implications for the placement of functional groups on concave molecular surfaces.

Alkynes↗
PubMed2002

Chemical mediation of egg capsule deposition by mud snails.

Mud snails (Ilyanassa obsoleta = Nassarius obsoletus = Nassa obsoleta) deposit eggs in protective capsules on hard substrata in soft bottom environments. We studied sites of egg capsule deposition and snail movement responses to odors to determine if chemoreception plays a role in deposition site selection. From results of field surveys, laboratory experiments, and field experiments, we conclude that mud snails use chemoreception for capsule deposition. Attractive odors originate from mud snail and whelk egg capsules and from living bivalves. Evidence for attractive odors from conspecifics is equivocal. Capsules are deposited on living odor sources and nearby hard substrates. We hypothesize that deposition of capsules on living substrates increases the likelihood that embryos will survive by decreasing the chance of smothering of embryos by sediments.

Animals↗
PubMed1993

Chemistry of collagen cross-links: glucose-mediated covalent cross-linking of type-IV collagen in lens capsules.

The incubation of lens capsules with glucose in vitro resulted in changes in the mechanical and thermal properties of type-IV collagen consistent with increased cross-linking. Differential scanning calorimetry (d.s.c.) of fresh lens capsules showed two major peaks at melting temperatures Tm 1 and Tm 2 at approx. 54 degrees C and 90 degrees C, which can be attributed to the denaturation of the triple helix and 7S domains respectively. Glycosylation of lens capsules in vitro for 24 weeks caused an increase in Tm 1 from 54 degrees C to 61 degrees C, while non-glycosylated, control incubated capsules increased to a Tm 1 of 57 degrees C. The higher temperature required to denature the type-IV collagen after incubation in vitro suggested increased intermolecular cross-linking. Glycosylated lens capsules were more brittle than fresh samples, breaking at a maximum strain of 36.8 +/- 1.8% compared with 75.6 +/- 6.3% for the fresh samples. The stress at maximum strain (or 'strength') was dramatically reduced from 12.0 to 4.7 N.mm.mg-1 after glycosylation in vitro. The increased constraints within the system leading to loss of strength and increased brittleness suggested not only the presence of more cross-links but a difference in the location of these cross-links compared with the natural lysyl-aldehyde-derived cross-links. The chemical nature of the fluorescent glucose-derived cross-link following glycosylation was determined as pentosidine, at a concentration of 1 pentosidine molecule per 600 collagen molecules after 24 weeks incubation. Pentosidine was also determined in the lens capsules obtained from uncontrolled diabetics at a level of about 1 per 100 collagen molecules. The concentration of these pentosidine cross-links is far too small to account for the observed changes in the thermal and mechanical properties following incubation in vitro, clearly indicating that another as yet undefined, but apparently more important cross-linking mechanism mediated by glucose is taking place.

Animals↗
PubMed2000

Bismuth-based quadruple therapy for Helicobacter pylori - a single triple capsule plus lansoprazole.

BACKGROUND: Recently a new 'all in one' single capsule with the three components of bismuth-based triple therapy became available in trials for treating Helicobacter pylori. AIM: To investigate the efficacy and tolerability of this new capsule when combined with lansoprazole. METHODS: A total of 66 consecutive infected patients from a single centre received two single triple capsules four times daily and lansoprazole 30 mg b.d. for 7 days. Each capsule contained 60 mg of bismuth subcitrate, 125 mg of tetracycline and 125 mg of metronidazole. Endoscopy with biopsies for CLO-test, histology and culture from antrum and corpus was performed before and at least 5 weeks after treatment. RESULTS: The per protocol cure rate was 56/64 (88%, 95% CI: 79-95%); by intention-to-treat 56/65 (86%, 95% CI: 78-95%). The per protocol cure rate in metronidazole sensitive strains was 40/43 (93%, 95% CI: 85-100%); in resistant strains 5/9 (56%, 95% CI: 23-88%). There was one drop-out due to adverse events. CONCLUSIONS: It is possible to combine the components of bismuth-based triple therapy into a single capsule. Based on the results it can be assumed that the capsule releases its content in the stomach. When combined with lansoprazole it reaches high cure rates, especially in metronidazole sensitive strains. This new approach simplifies bismuth-based anti-Helicobacter therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2005

Sensitivity and specificity of the suspected blood identification system in video capsule enteroscopy.

BACKGROUND AND STUDY AIMS: Capsule enteroscopy has become a standard tool for the evaluation of obscure gastrointestinal bleeding. Reviewing the video recordings of capsule examinations is time-consuming and requires prolonged attention. Recently, software that can recognize the frames containing "red spots", the Suspected Blood Identification system (SBIS), has been developed with the aim of assisting in the analysis of video recordings. We assessed the sensitivity and specificity of the SBIS in patients undergoing capsule enteroscopy. PATIENTS AND METHODS: 100 consecutive patients underwent capsule enteroscopy at our tertiary referral center, for the following indications: obscure gastrointestinal bleeding (75 patients), metastatic carcinoid (7 patients) known or suspected Crohn's disease (5 patients), miscellaneous (13 patients). Capsule endoscopy was carried out by the standard method. Four gastroenterologists, experienced in capsule endoscopy, reviewed the recordings. RESULTS: Small-bowel visualization was obtained in 95 cases. The physicians identified 209 "red spots", 54 of which (25.8%) were also identified by the SBIS. The overall sensitivity, specificity, and positive and negative predictive values of the SBIS, calculated on the number of true-positive, true-negative, false-positive and false-negative results, were 40.9%, 70.7%, 69.2% and 42.6%, respectively. Sensitivity was higher for the identification of red blood (60.9%) than for nonbleeding "red" lesions such as arteriovenous malformations (25.8%). CONCLUSIONS: The SBIS has low sensitivity and specificity. It can be used as a complementary and rapid screening tool, but complete review of the recordings is still necessary.

Adult↗
PubMed2006

Use of anticoagulation during wireless capsule endoscopy for the investigation of recurrent obscure gastrointestinal bleeding.

Detecting the source of obscure gastrointestinal bleeding can be difficult. Capsule endoscopy is a promising diagnostic tool for investigating patients with this condition, although identifying the source of intermittent or low-grade bleeding remains a diagnostic challenge. We present case reports of two patients with obscure gastrointestinal bleeding, in whom the source of recurrent bleeding episodes was diagnosed by capsule endoscopy while they were on anticoagulation therapy. The first patient, an 81-year-old white woman, was on long-term oral anticoagulation because she had chronic atrial fibrillation. Capsule endoscopy demonstrated a bleeding tumor in the region of the terminal ileum. The second patient, a 59-year-old white man, underwent an initial capsule endoscopy, which was negative. After initiation of anticoagulation with heparin, a second capsule endoscopy procedure in this patient revealed several small bleeding lesions in the proximal small bowel. In both cases a gastrointestinal stromal tumor was identified as the bleeding source and was resected. These two cases demonstrate that provocation of bleeding during capsule endoscopy may increase its sensitivity.

Aged, 80 and over↗
PubMed2001

CpsB is a modulator of capsule-associated tyrosine kinase activity in Streptococcus pneumoniae.

Tyrosine phosphorylation is associated with polysaccharide synthesis in a number of Gram-positive and Gram-negative bacteria. In Streptococcus pneumoniae, CpsB, CpsC, and CpsD affect tyrosine phosphorylation and are critical for the production of a mature capsule in vitro. To characterize the interactions between these proteins and the phosphorylation event they modulate, cps2B, cps2C, and cps2D from the capsule type 2 S. pneumoniae D39 were cloned and expressed both individually and in combination in Escherichia coli. Cps2D purified from E. coli was not phosphorylated unless it was co-expressed with its cognate transmembrane domain, Cps2C. Purified phosphorylated Cps2D had tyrosine kinase activity and could phosphorylate both dephosphorylated Cps2D and an exogenous substrate (poly-Glu-Tyr) in the absence of ATP. Cps2B exhibited phosphatase activity against both purified phosphorylated Cps2D and p-nitrophenyl phosphate. An additional role for Cps2B as an inhibitor of Cps2D phosphorylation was demonstrated in both co-expression experiments in E. coli and in vitro experiments where it blocked the transphosphorylation of Cps2D even in the presence of the phosphatase inhibitor sodium orthovanadate. cps2C and cps2D deletion mutants in S. pneumoniae produced no detectable mature capsule during laboratory culture. Both were avirulent in systemic mouse infections and were unable to colonize the nasopharynx, suggesting that the failure to produce capsule was not dependent on the environment. Based on these results, we propose a model for capsule regulation where CpsB, CpsC, CpsD, and ATP form a stable complex that enhances capsule synthesis.

Animals↗
PubMedDate not supplied

The effect of seprafilm and interceed on capsule formation around silicone discs in a rat model.

The insertion of a foreign substance, such as a breast implant into mammalian soft tissues, evokes a wound healing response that culminates in a dense connective-tissue envelope or capsule surrounding the implant. Several biodegradable products, such as Seprafilm (carboxymethylcellulose and hyaluronic acid) and Interceed (oxidized regenerated cellulose), have been demonstrated to inhibit adhesions in abdominal and gynecologic surgery. The ability of these cellulose compounds to inhibit capsule formation was addressed in this investigation. Twenty-eight rats were implanted intermuscularly with either plain silicone discs (10 animals), discs wrapped in Seprafilm (10 animals), or discs covered with Interceed (8 animals). Additional control animals (6 animals) consisted of two that had sham operations, two animals implanted with Seprafilm only, and two more implanted with Interceed only. Animals were sacrificed in pairs at varying time intervals after implantation (2, 4, 8, 12, and 16 wk), and the tissues around the silicone discs were analyzed with light microscopy. Control animals were sacrificed at 8 wk. Both Interceed and Seprafilm slowed the formation of a capsule around the implanted silicone discs as both products were degraded. Evidence of residual material, presumably Seprafilm and Interceed, was seen intracellularly in animals 3 to 4 mo, respectively, after implantation. However, neither material prevented the eventual formation of a fibrous capsule around the silicone discs. The results of this study suggest that encapsulating foreign substances with these types of biodegradable materials will not significantly hinder capsule formation. A more direct attack on the wound healing mechanism may provide a definitive solution for capsule problems with implanted materials.

Animals↗
PubMed1997

Epitope location in the Cryptococcus neoformans capsule is a determinant of antibody efficacy.

Monoclonal antibodies (mAbs) to the polysaccharide capsule of Cryptococcus neoformans can prolong survival in mice. However, the properties of antibodies that mediate protection are not fully understood. The IgM mAbs 12A1 and 13F1 originated from the same B cell and differ only by somatic mutations in their variable regions; yet mAb 12A1 protects against serotype D infection, while mAb 13F1 does not. Phage peptide display libraries were used to analyze the fine specificity of these two mAbs. The selection of distinct peptide motifs from identical libraries confirmed that mAbs 12A1 and 13F1 bound to two distinct epitopes. Immunofluorescence and immunoelectron microscopy studies revealed differences in antibody localization within the capsule of serotype D strain; mAb 12A1 bound to the outer rim of the capsule resulting in an annular pattern, whereas mAb 13F1 bound throughout the capsule and had a punctate appearance. The difference in the binding pattern of mAb 12A1 and 13F1 was not observed on serotype A organisms, where both mAbs bound to the capsule with an annular fluorescence pattern. The fluorescence pattern of binding correlated with protective efficacy; mAb 13F1 prolonged survival of mice infected with the J11 serotype A strain (annular fluorescence), but not serotype D strains (punctate pattern). Annular binding, but not punctate binding, was associated with increased opsonic efficacy for phagocytosis of C. neoformans by J774.16 macrophage-like cells. The correlation between capsular binding pattern, opsonic activity, and ability to prolong survival suggests that the efficacy of anticryptococcal antibodies is dependent upon where they bind in the polysaccharide capsule.

Animals↗
PubMed2003

Effects of in vitro production on horse embryo morphology, cytoskeletal characteristics, and blastocyst capsule formation.

Blastocyst formation rates during horse embryo in vitro production (IVP) are disappointing, and embryos that blastulate in culture fail to produce the characteristic and vital glycoprotein capsule. The aim of this study was to evaluate the impact of IVP on horse embryo development and capsule formation. IVP embryos were produced by intracytoplasmic sperm injection of in vitro matured oocytes and either culture in synthetic oviduct fluid (SOF) or temporary transfer to the oviduct of a ewe. Control embryos were flushed from the uterus of mares 6-9 days after ovulation. Embryo morphology was evaluated with light microscopy, and multiphoton scanning confocal microscopy was used to examine the distribution of microfilaments (AlexaFluor-Phalloidin stained) and the rate of apoptosis (cells with fragmented or terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling-positive nuclei). To examine the influence of culture on capsule formation, conceptuses were stained with a monoclonal antibody specific for capsular glycoproteins (OC-1). The blastocyst rate was higher for zygotes transferred to a sheep's oviduct (16%) than for those cultured in SOF (6.3%). Day 7 IVP embryos were small and compact with relatively few cells, little or no blastocoele, and an indistinct inner cell mass. IVP embryos had high percentages of apoptotic cells (10% versus 0.3% for in vivo embryos) and irregularly distributed microfilaments. Although they secreted capsular glycoproteins, the latter did not form a normal capsule but instead permeated into the zona pellucida or remained in patches on the trophectodermal surface. These results demonstrate that the initial layer of capsule is composed of OC-1-reactive glycoproteins and that embryo development ex vivo is retarded and aberrant, with capsule formation failing as a result of failed glycoprotein aggregation.

Actin Cytoskeleton↗
PubMed1995

Complications related to retained breast implant capsules.

Citing evidence that breast implant-related capsules resolve uneventfully, surgeons have elected to leave the capsules in place when implants are removed because capsulectomy adds both morbidity and expense to the procedure. However, recent clinical and histopathologic evidence suggests that uneventful resolution is not always the case, and several potential problems may arise from retained capsules after removal of the implant. Retained implant capsules may result in a spiculated mass suspicious for carcinoma, dense calcifications that obscure neighboring breast tissue on subsequent imaging studies, and cystic masses due to persistent serous effusion, expansile hematoma, or encapsulated silicone filled cysts. Furthermore, retained capsules are a reservoir of implant-related foreign material in the case of silicone gel-filled implants and textured implants promoting tissue ingrowth. To avoid complications from retained capsules, total capsulectomy or postoperative surveillance should be offered to patients.

Aged↗
PubMed2002

Successful transplantation of three tissue-engineered cell types using capsule induction technique and fibrin glue as a delivery vehicle.

Recent advances in cell biology and tissue engineering have used various delivery vehicles for transplanting varying cell cultures with limited success. These techniques are frequently complicated by tissue necrosis, infection, and resorption. The purpose of this study was to investigate whether urothelium cells, tracheal epithelial cells, and preadipocytes cultured in vitro could be successfully transplanted onto a prefabricated capsule surface by using fibrin glue as a delivery vehicle, with the ultimate goal for use in reconstruction. In the first step of the animal study, tissue specimens (bladder urothelium, tracheal epithelial cells, epididymal fat pad) were harvested for in vitro cell culturing, and a silicone block was implanted subcutaneously or within the anterior rectus sheath to induce capsule formation. After 6 to 10 days, when primary cultures were confluent, the animals were re-anesthetized, the newly formed capsule pouches were incised, and the suspensions of cultured urothelia cells (n = 40), tracheal epithelial cells (n = 32), and preadipocytes (n = 40) were implanted onto the capsule surface in two groups, one using standard culture medium as a delivery vehicle and the second using fibrin glue. Histologic sections were taken, and different histomorphologic studies were performed according to tissue type. Consistently in all animals, a highly vascularized capsule was induced by the silicon material. In all animals in which the authors used fibrin glue as a delivery vehicle, they could demonstrate a successful reimplantation of cultured urothelium cells, tracheal epithelial cells, or preadipocytes. Their animal studies showed that capsule induction in combination with fibrin glue as a delivery vehicle is a successful model for transplantation of different in vivo cultured tissue types.

Adipocytes↗
PubMed2005

Incision of the intervertebral disc induces disintegration and increases permeability of the dorsal root ganglion capsule.

STUDY DESIGN: The origin and the barrier properties of the characteristic reaction at the surface of the dorsal root ganglion (DRG) exposed to the nucleus pulposus was studied using Alcian-Blue staining, van Gieson staining, and the application of Evans Blue Albumin (EBA) complex in rats. OBJECTIVE: To study the origin and the barrier properties of the capsule, including the characteristic reaction, at the surface of the DRG exposed to the nucleus pulposus. SUMMARY OF BACKGROUND DATA: Local application of nucleus pulposus may induce a characteristic reaction at the surface of the DRG. This reaction histologically resembles an acute inflammatory reaction. However, it is not evident if this is a swelling of the DRG capsule, if it is located between the capsule and neurons of the DRG, or if it is only an attached nucleus pulposus. METHODS: Nucleus pulposus from the discs was obtained. The nucleus pulposus was smeared on glass slides. Alcian-Blue with hematoxylin and eosin staining was performed for each smear. Herniation of the nucleus pulposus was made in the L4-L5 disc in rats. The L4 DRGs were resected 3, 24, and 72 hours after surgery, and sectioned. The sections were processed for Alcian-Blue staining, van Gieson staining, and EBA complex infiltration. The sections were observed using light or fluorescent microscopy. RESULTS: Smear of nucleus pulposus was stained bright blue indicating mucins. A characteristic reaction, "inflammatory crescent," was confirmed at the surface of the DRG exposed to the nucleus pulposus. No mucins were observed in the crescent using Alcian-Blue. The results of van Gieson staining showed that the reaction started both inside and outside the elastic fiber layer, the DRG capsule, within 3 hours. The EBA complex was capable of infiltrating into the DRG capsule 24 hours after disc incision. CONCLUSIONS: The disintegrated capsule showed an increased permeability even for a large molecule as albumin, which indicates a possible entrance route for various substances induced by locally applied nucleus pulposus.

Animals↗