The use of preserved equine renal capsule to repair lamellar corneal lesions in normal dogs

The purpose of this study was to evaluate the use of equine renal capsule preserved in 98% glycerine to repair lamellar corneal lesions in normal dogs. For this purpose, 12 dogs, divided into six groups (n = 2), were used to evaluate the 1st to 7th day, 15th day and 30th to 60th postoperative day. In order to perform the histologic study, the clinical procedures were analyzed, while the recipient's corneas were collected. The photophobia and blepharospasm also were more intense in the 1st to 7th postoperative day, and regressed in the 15th postoperative day. Therefore, the edema and the vascular events were both more frequent in the intermediary phases and regressed in the late periods. On the other hand, the morphological evaluation demonstrated an inflamatory exudate, also in the intermediary and late periods. These results suggested that the equine renal preserved capsule could be a useful alternative tissue to repair lamellar corneal lesions in dogs.

Temporal variation in egg-capsule deposition by Nassarius vibex (Gastropoda: Nassariidae)

The morphology and the deposition periods of egg capsules by the bruised nassa Nassarius vibex were investigated on two beaches located on the southeast coast of Brazil. The nassariids were associated with the charru mussel Mytella charruana, which forms beds on soft mud-bottoms. A total of 1558 capsules were collected, only from the fronds of the green alga Ulva lactuca, 859 for Camaroeiro Beach and 699 for Cidade Beach. The mean sizes of the egg capsules and numbers of eggs or larvae per capsule were similar on the two beaches, as were the periods of capsule deposition. At Camaroeiro Beach, capsules first appeared in May 2006, reached a peak in August 2006, and disappeared in December 2006. At Cidade Beach, the first capsules were recorded in July 2006, with a peak in August 2006. A second peak was also observed at this beach between January 2007 and April 2007. The two periods of deposition recorded at the latter beach may indicate two periods of recruitment in the same year for N. vibex. Regarding the influence of intertidal level on capsule deposition, there was a significant difference in the number of capsules between the levels at Camaroeiro Beach (F= 7.445, p<0.05), and for the second capsule-deposition peak at Cidade Beach (F= 6.382, p<0.05). This study revealed a selective pattern of capsule deposition, with individuals of N. vibex using only fronds of U. lactuca. This process was influenced by the morphodynamics of the two beaches, with the nassariids maximizing the survival of embryos by depositing more capsules and more eggs per capsule in better-protected parts of the mytilid beds.

Capsule Locus Polymorphism among Distinct Lineages of Enterococcus faecalis Isolated from Canals of Root-filled Teeth with Periapical Lesions

Introduction: Although Enterococcus faecalis is a member of the normal microbiota, it is also a major cause of nosocomial infections. Some strains of E. faecalis produce capsule, which contributes to pathogenesis through evasion of host defenses, and its production is dependent on the capsule (cps) operon polymorphism. This study investigated cps locus polymorphism in distinct lineages of E. faecalis isolated from canals of root-filled teeth with periapical lesions. Methods: Twenty-two E. faecalis isolates were evaluated regarding the cps operon polymorphism and genetic diversity. The 3 known CPS types were determined by polymerase chain reaction. This information was correlated with multilocus sequence typing data, which were used to define genetic lineages. Results: cpsA and cpsB were the only detected genes within the cps operon in 62.5% of E. faecalis strains (14/22), indicative of genotype CPS 1, which lacks capsule expression. The essential genes in the cps operon for capsule production were detected in the remaining strains, whereas 3 belonged to genotype CPS 5 and 5 strains to genotype CPS 2. A total of 14 sequence types (STs) were resolved in 22 E. faecalis isolates. Comparison with the E. faecalis international multilocus sequence typing database revealed that 9 STs were previously found, and that the 5 STs were novel. Conclusions: Certain E. faecalis genotypes from canals of root-filled teeth with periapical lesions belong to lineages associated with capsule expression and production of multiple virulence factors, which might account for their increased pathogenic potential. (J Endod 2012;38:58-61)

Feasibility and diagnostic effectiveness of new capsule endoscopy techniques

Since its approval by FDA in 2001, capsule endoscopy revolutionized the study of small bowel. One of the main limitations of its diffusion has been the high cost. More recently, a new videocapsule system (OMOM CE) has been developed in China and obtained the CE mark. Its cost is approximately half that of other capsule systems. However, there are few studies regarding the clinical experience with this new videocapsule system and none of them has been performed in the western world. Among the limitations of capsule endoscopy, there is also one linked to the diagnostic yield. The rapid transit of the device in the proximal segments implies a high risk of false negatives; an indirect confirmation of this limit is offered by the poor ability to identify the papilla of Vater. In addition, recent studies show that in patients with obscure gastrointestinal bleeding, the negative outcome of capsule endoscopy is correlated to a significant risk of recurrence of anemia in the short term, as well as the presence of small bowel lesions documented by a second capsule endoscopy. It was recently approved the use of a new device called "CapsoCam" (CapsoVision, Inc. Saratoga) characterized by four side cameras that offer a panoramic view of 360 degrees, instead of the front to 160°. Two recent pilot studies showed comparable safety profiles and diagnostic yield with the more standardized capsule. Namely, side vision has made possible a clear visualization of the papilla in 70% of cases. The aim of our study is to evaluate the feasibility and diagnostic yield of these two new devices, which first may allow a reduction in costs. Moreover, their complementary use could lead to a recovery diagnostic in patients with false negative results in an initial investigation.

Escherichia coli variants in periprosthetic joint infection: diagnostic challenges with sessile bacteria and sonication

The diagnostic yield of prosthetic joint-associated infection is hampered by the phenotypic change of bacteria into a sessile and resistant form, also called biofilm. With sonication, adherent bacteria can be dislodged from the prosthesis. Species identification may be difficult because of their variations in phenotypic appearance and biochemical reaction. We have studied the phenotypic, genotypic, and biochemical properties of Escherichia coli variants isolated from a periprosthetic joint infection. The strains were collected from synovial fluid, periprosthetic tissue, and fluid from the explanted and sonicated prosthesis. Isolates from synovial fluid revealed a normal phenotype, whereas a few variants from periprosthetic tissue and all isolates from sonication fluid showed different morphological features (including small-colony variants). All isolates from sonication fluid were beta-galactosidase negative and nonmotile; most were indole negative. Because of further variations in biochemical properties, species identification was false or not possible in 50% of the isolates included in this study. In contrast to normal phenotypes, variants were resistant to aminoglycosides. Typing of the isolates using pulsed-field gel electrophoresis yielded nonidentical banding patterns, but all strains were assigned to the same clonal origin when compared with 207 unrelated E. coli isolates. The bacteria were repeatedly passaged on culture media and reanalyzed. Thereafter, most variants reverted to normal phenotype and regained their motility and certain biochemical properties. In addition, some variants displayed aminoglycoside susceptibility after reversion. Sonication of an explanted prosthesis allows insight into the lifestyle of bacteria in biofilms. Since sonication fluid also reveals dislodged sessile forms, species identification of such variants may be misleading.

[Periprosthetic joint infections - a review for general practitioners]

The number of prosthetic joint implantation is continuously increasing. Periprosthetic joint infection is a rare but serious complication. The correct diagnosis is essential for successful treatment. It requires the close collaboration between general practitioners, orthopaedic surgeons and infectious disease specialists. A delayed diagnosis sets hurdles to the medical and surgical treatment. Also, antimicrobial treatment without proper microbiological sampling must be avoided. Swabs from wounds are not helpful, because the results represent the skin flora, but not the causative pathogen of infection. The general practitioner is the first physician that patients contact and has, therefore, a central role in diagnosing and managing periprosthetic joint infections. In this review, classification, diagnostic means and treatment concepts of periprosthetic joint infections are presented.

Hip capsule dimensions in patients with femoroacetabular impingement: a pilot study

Joint-preserving hip surgery, either arthroscopic or open, increasingly is used for the treatment of symptomatic femoroacetabular impingement (FAI). As a consequence of surgery, thickening of the joint capsule and intraarticular adhesions between the labrum and joint capsule and between the femoral neck and the joint capsule have been observed. These alterations are believed to cause persistent pain and reduced range of motion. Because the diagnosis is made with MR arthrography, knowledge of the normal capsular anatomy and thickness on MRI in patients is important. To date there is no such information available.

Capsule type of Streptococcus pneumoniae determines growth phenotype

The polysaccharide capsule of Streptococcus pneumoniae defines over ninety serotypes, which differ in their carriage prevalence and invasiveness for poorly understood reasons. Recently, an inverse correlation between carriage prevalence and oligosaccharide structure of a given capsule has been described. Our previous work suggested a link between serotype and growth in vitro. Here we investigate whether capsule production interferes with growth in vitro and whether this predicts carriage prevalence in vivo. Eighty-one capsule switch mutants were constructed representing nine different serotypes, five of low (4, 7F, 14, 15, 18C) and four of high carriage prevalence (6B, 9V, 19F, 23F). Growth (length of lag phase, maximum optical density) of wildtype strains, nontypeable mutants and capsule switch mutants was studied in nutrient-restricted Lacks medium (MLM) and in rich undefined brain heart infusion broth supplemented with 5% foetal calf serum (BHI+FCS). In MLM growth phenotype depended on, and was transferred with, capsule operon type. Colonization efficiency of mouse nasopharynx also depended on, and was transferred with, capsule operon type. Capsule production interfered with growth, which correlated inversely with serotype-specific carriage prevalence. Serotypes with better growth and higher carriage prevalence produced thicker capsules (by electron microscopy, FITC-dextran exclusion assays and HPLC) than serotypes with delayed growth and low carriage prevalence. However, expression of cpsA, the first capsule gene, (by quantitative RT-PCR) correlated inversely with capsule thickness. Energy spent for capsule production (incorporation of H3-glucose) relative to amount of capsule produced was higher for serotypes with low carriage prevalence. Experiments in BHI+FCS showed overall better bacterial growth and more capsule production than growth in MLM and differences between serotypes were no longer apparent. Production of polysaccharide capsule in S. pneumoniae interferes with growth in nutrient-limiting conditions probably by competition for energy against the central metabolism. Serotype-specific nasopharyngeal carriage prevalence in vivo is predicted by the growth phenotype.

Diagnosis of periprosthetic joint infections in clinical practice

The diagnosis of a periprosthetic joint infection (PJI) can be challenging, either because of the variable clinical presentation or because of previous antimicrobial treatment interfering with the detection of the pathogen. In recent years, various means to diagnose PJI have been analyzed. These include invasive and non-invasive laboratory tests, imaging procedures, and novel techniques such as sonication of implants and the use of molecular microbiology. In this review, both established and novel diagnostic procedures are presented. An algorithm for detecting PJI in patients with acute and chronic symptoms is proposed.

Risk factors for periprosthetic ankle joint infection: a case-control study

Periprosthetic ankle joint infection is a feared complication of total ankle arthroplasty because the implant fails in the majority of cases. However, risk factors for developing these infections are unknown.

In vitro expression of the first capsule gene of Streptococcus pneumoniae, cpsA, is associated with serotype-specific colonization prevalence and invasiveness

The polysaccharide capsule protects Streptococcus pneumoniae from phagocytosis during invasive infection, but inhibits adherence. Serotypes vary in their tendency to colonize the nasopharynx or cause invasive infection, and differences in capsule expression may play a role. Expression of the first gene of the capsule operon, cpsA, during in vitro growth of 43 clinical isolates representing 14 common pneumococcal serotypes was compared using quantitative RT-PCR. Serotypes associated with invasive infection (1, 4, 5, 7F, 8 and 14) expressed an average of twofold (P=0.0003) more cpsA than serotypes associated with nasopharyngeal colonization (6A, 6B, 9V, 15, 18C, 19F, 23F and 33). There was no difference in cpsA expression in response to growth under environmental oxygen or anaerobic conditions between the invasive and colonizing transparent strains tested: oxygen concentration did not affect cpsA expression in either the invasive or the colonizing transparent strains. Expression of cpsA at OD(600) 0.6 tended to be greater in strains with a longer lag phase during in vitro growth (P=0.07). Therefore, cpsA expression under ambient oxygen concentrations correlates with serotype-specific invasiveness and is inversely associated with the prevalence of serotype-specific carriage.

Capsule genes of Streptococcus pneumoniae influence growth in vitro

Recently, we showed that the in vitro lag phase correlates with the pneumococcal serotype. This study investigated the role of capsule genes in bacterial growth using strain D39. Deletion of the entire capsule operon induced a significantly prolonged lag phase in Todd Hewitt broth (P=0.0002). However, partial deletions showed a different influence on the lag phase. Supplementation of media with 5% fetal bovine serum restored normal growth, at least partially, in mutants with a prolonged lag phase. Therefore, pneumococcal capsule gene products influence bacterial growth in vitro in strain D39.