Xenograft transplantation

Interest in xenotransplantation has increased because conventional organ transplantation has been limited by a shortage of human organs. Although xenotransplantation could alleviate the existing and anticipated need for tissues and organs, the application is hindered by various biologic obstacles. This article reviews the basis for the demand for xenotransplantation, the obstacles to clinical application, and potential approaches to overcoming those obstacles.     

Congenital esophageal stenosis

Congenital esophageal stenosis CES is an uncommon anomaly that rarely goes undiagnosed until adulthood. We report 2 cases of CES. The first was a one-month-old baby boy who was referred for work up of swallowing disorder and recurrent pneumonias. The diagnosis was confirmed by a continuous fluoroscopic esophagogram, and endoscopic exploration. Simple dilatation resolved his symptoms completely. The second was an 18-month-old boy, who was referred with a feeding gastrostomy due to complete esophageal obstruction. Resection and end-to-end anastomosis was performed with uneventful postoperative course.     

Characterization of a cytosolic inhibitor of calf estrogen receptor binding to nuclei

An inhibitory component that diminishes estrogen receptor (ER) binding to nuclei in vitro is present in cytosol prepared from calf uterus. The inhibitor is heat stable and resistant to enzymatic treatment with trypsin, chymotrypsin, proteinase K, deoxyribonuclease I, or ribonucleases A, T1, and U2. Results of chromatography on DEAE-cellulose and Sephadex G-150 indicate that the factor is a negatively charged macromolecule. Inhibitory activity is sensitive to sequential digestion with chondroitinase ABC, hyaluronidase, and heparinase. Approximately 70% of the inhibitory activity is destroyed by treatment with heparinase alone. Heparitinase destroys only 30% of this activity. Furthermore, the addition of pure hyaluronic acid or chondroitin sulfate to the ER-nuclei binding assay results in little inhibition, whereas addition of heparin inhibits 75% of receptor binding. Overall, these results indicate that glycosaminoglycans, present in bovine uterine cytosol, are capable of inhibiting ER-nuclei interactions. The most potent inhibitory glycosaminoglycan displays heparin-like characteristics.     

Passage of tube per rectum: an unusual complication of a ventriculoperitoneal shunt

A very rare complication of a ventriculoperitoneal (VP) shunt is reported. The peritoneal catheter perforated the colon of a two-year-old child, causing diarrhoea which was misdiagnosed as gastroenteritis. The diagnosis became obvious when the catheter was extruded from the child's anus.     

Basement membrane and the SIKVAV laminin-derived peptide promote tumor growth and metastases

Summary Laminin, the major glycoprotein component of basement membrane, promotes the malignant phenotype. Cells which are adherent to laminin are more malignant than the non-adherent cells and in certain tumor cells, the number of laminin receptors is positively correlated with malignancy. Laminin also increases collagenase IV activity, an enzyme demonstrated to be critical for tumor spread. A site on laminin, containing the amino acid sequence SIKVAV, has been identified which when injected intravenously with B16F10 melanoma cells, causes an increase in the number of colonies on the surface of the lungs. This peptide does not affect tumor cell arrest in the vasculature or the immune system. It does promote angiogenesis in various in vitro and in vivo models, thereby facilitating tumor cell survival.When a complex mixture of laminin-enriched basement membrane components (Matrigel) is coinjected with tumor cells subcutaneously, tumor incidence and growth increases. Various tumor cell lines and primary isolates, which previously could not form tumors in mice, can be induced to grow rapidly in the presence of Matrigel. Slowly growing tumors or arrested tumors can also be induced to grow more quickly with additional injections of Matrigel. When an SIKVAV-containing synthetic peptide is coinjected with B16F10 tumor cells and Matrigel subcutaneously in mice, larger tumors are formed than that observed with either Matrigel or cells alone. Such studies define the role of laminin in tumor growth and spread and generate new models for studying therapeutic agents. Of particular interest is the ability to grow primary isolates which generally do not grow in mice.     

Three-dimensional assessment of the asymptomatic and post-stroke shoulder: intra-rater test–retest reliability and within-subject repeatability of the palpation and digitization approach

Purpose: Altered three-dimensional (3D) joint kinematics can contribute to shoulder pathology, including post-stroke shoulder pain. Reliable assessment methods enable comparative studies between asymptomatic shoulders of healthy subjects and painful shoulders of post-stroke subjects, and could inform treatment planning for post-stroke shoulder pain. The study purpose was to establish intra-rater test–retest reliability and within-subject repeatability of a palpation/digitization protocol, which assesses 3D clavicular/scapular/humeral rotations, in asymptomatic and painful post-stroke shoulders.

Methods: Repeated measurements of 3D clavicular/scapular/humeral joint/segment rotations were obtained using palpation/digitization in 32 asymptomatic and six painful post-stroke shoulders during four reaching postures (rest/flexion/abduction/external rotation). Intra-class correlation coefficients (ICCs), standard error of the measurement and 95% confidence intervals were calculated.

Results: All ICC values indicated high to very high test–retest reliability (≥0.70), with lower reliability for scapular anterior/posterior tilt during external rotation in asymptomatic subjects, and scapular medial/lateral rotation, humeral horizontal abduction/adduction and axial rotation during abduction in post-stroke subjects. All standard error of measurement values demonstrated within-subject repeatability error ≤5° for all clavicular/scapular/humeral joint/segment rotations (asymptomatic ≤3.75°; post-stroke ≤5.0°), except for humeral axial rotation (asymptomatic ≤5°; post-stroke ≤15°).

Conclusions: This noninvasive, clinically feasible palpation/digitization protocol was reliable and repeatable in asymptomatic shoulders, and in a smaller sample of painful post-stroke shoulders.

• Implications for Rehabilitation

• In the clinical setting, a reliable and repeatable noninvasive method for assessment of three-dimensional (3D) clavicular/scapular/humeral joint orientation and range of motion (ROM) is currently required.

• The established reliability and repeatability of this proposed palpation/digitization protocol will enable comparative 3D ROM studies between asymptomatic and post-stroke shoulders, which will further inform treatment planning.

• Intra-rater test–retest repeatability, which is measured by the standard error of the measure, indicates the range of error associated with a single test measure. Therefore, clinicians can use the standard error of the measure to determine the “true” differences between pre-treatment and post-treatment test scores.

     

Best evidence topic report. Ultrasound in the diagnosis of testicular torsion

A short cut review was carried out to establish whether colour Doppler ultrasound is more sensitive than clinical examination in ruling out testicular torsion. A total of 284 papers were found using the reported search, of which seven presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. A clinical bottom line is stated.