Envenoming by a number of species of snake may affect the myocardium or cause electrocardiographic changes; several different mechanisms have been proposed. In a prospective study of snake bite in Papua New Guinea, electrocardiographic changes were observed in 36 of 69 patients (52%) envenomed by the taipan (Oxyuranus scutellatus), 2 of 6 (33%) envenomed by death adders (Acanthophis sp.) and one envenomed by the brown snake (Pseudonaja textilis). Septal T wave inversion and bradycardias, including atrioventricular block, were the commonest abnormalities. There was no haemodynamic deterioration. The cause of these changes is uncertain; only 2 of 24 patients (8.3%) with electrocardiographic changes had markedly elevated plasma concentrations of cardiac troponin T, a sensitive and specific marker of myocardial damage. This suggests that myocardial damage is uncommon following bites by these species. Electrocardiographic abnormalities are most likely to have been caused by a direct toxic effect of a venom component upon cardiac myocyte function; in taipan bites, taicatoxin, a calcium channel blocker, might be responsible.

Animals↗

PubMedDate not supplied

Characterization of murine autologous salivary gland graft cells: a model for use with an artificial salivary gland.

The purpose of this study was to examine the growth and key functional abilities of primary cultures of salivary epithelial cells toward developing an artificial salivary gland. Cultures of epithelial cells originating from submandibular glands of BALB/c mice were established. Parenchymal cells were isolated by a Percoll gradient technique and thereafter seeded on irradiated NIH 3T3 fibroblasts serving as a feeder layer. The isolated cells were termed autologous salivary gland epithelial (ASGE) cells and could be cultivated for at least five passages (time limit of experiments). ASGE cells presented the typical organizational behavior of epithelial cells and electron microscopy, as well as immunostaining for cytokeratins, confirmed their epithelial origin. Furthermore, measurements of transepithelial resistance and water permeability indicated the ability of the ASGE cells to form a functional epithelial barrier. This study suggests that primary salivary epithelial cells can be obtained that exhibit critical characteristics needed for use with an artificial secretory device.

Animals↗

PubMedDate not supplied

Cushing's syndrome in infancy: difficulties in diagnosis and adrenal autotransplantation after therapeutic adrenalectomy.

A two-month-old female with clinical manifestations of Cushing's syndrome including mild virilization exhibited an unusual steroid pattern illustrating difficulties in diagnosis of this disorder in infancy. Unequivocal abnormalities were limited to serial elevations of serum cortisol concentration, hyperresponsiveness to ACTH, resistance of serum cortisol to dexamethasone suppression, and elevation of testosterone and dehydroepiandrosterone sulfate concentration. On the other hand, twenty-four hour urinary 17-hydroxysteroid, 17-ketosteroid, free cortisol, and 6B-hydroxycortisol excretion were normal for the age. At laparotomy the adrenals were only minimally enlarged, and their architecture was normal by light microscopy. Following total adrenalectomy, adrenal slices were transplanted into the rectus abdominis muscles. Progressive hypertension developed three weeks later, suggesting adrenal regeneration. The infant then developed acute Salmonella enteritis and expired. At autopsy, the adrenal transplant showed outer cortical preservation, inner zone degeneration, and some growth into the surrounding tissue. The unfavorable outcome notwithstanding, this study adds to existing data in the adult that adrenal autotransplantation may have significant therapeutic value in Cushing's syndrome treated by bilateral adrenalectomy.

17-Hydroxycorticosteroids↗

PubMedDate not supplied

Brimonidine (Alphagan): a clinical profile four years after launch.

The early information on the clinical efficacy, safety, and tolerability of brimonidine 0.2% were obtained from studies that compared brimonidine monotherapy with timolol and betaxolol. These studies showed its intra-ocular pressure lowering efficacy to be comparable with timolol and superior to betaxolol. The data from the timolol studies showed consistent results after four years. These findings have been confirmed by additional studies in the clinical setting. More recently, several clinical trials have been completed investigating the role of brimonidine as adjunctive medication to beta-blockers and as replacement therapy to other intraocular pressure lowering compounds. When added to beta-blockers, brimonidine is superior to dorzolamide, similar in efficacy but better tolerated than pilocarpine, and more predictable than latanoprost. Data from replacement studies have indicated that there may be advantages in replacing rather than adding medications in the treatment of glaucoma.

Adrenergic alpha-2 Receptor Agonists↗

PubMedDate not supplied

The fate of eyes with anterior chamber intra-ocular lenses.

A total of 143 anterior chamber (AC) intra-ocular lenses (IOL) of various designs were implanted in a five-year period and followed for 18 to 76 months. The lenses were inserted as a secondary implant after extracapsular cataract extraction (ECCE) complicated by vitrectomy, or after primary intra-capsular extraction. The complications (corneal edema, uveitis/glaucoma, extrusion/imbedding, cystoid macular edema), the final visual acuity and the need for removal of the IOL were analyzed. Only small differences were found between the different lenses but some association was found between complicated surgery (ECCE + vitrectomy) and a higher rate of complication, poorer visual outcome and more frequent need for IOL removal. Cystoid macular edema was encountered only in cases with complicated ECCE. A high percentage of other ocular pathologies was found among the cases, possibly implying that diseased eyes are more prone to surgical complications. An alternative to the AC-IOL in cases with a ruptured posterior capsule is the suture-supported posterior chamber IOL, but the flexible-loop AC-IOL may not yet be obsolete.

Anterior Chamber↗

PubMedDate not supplied

Hypertension and virilization caused by a unique desoxycorticosterone- and androgen-secreting adrenal adenoma.

We describe a rare androgen and desoxycorticosterone (DOC)-secreting adrenal tumor in a non-Cushingoid 14 year-old Haitian girl with secondary amenorrhea, hypertension and virilization. Her steroid pattern simulated an 11 beta-hydroxylation defect with notable elevation of adrenal androgens, 11-desoxycortisol (S), DOC, 17 alpha-hydroxyprogesterone and pregnenelone. Exogenous ACTH stimulated steroidogenesis. A CAT scan unfortunately failed to delineate an adrenal mass. Dexamethasone (DEX) was administered, therefore, which partially suppressed androgen levels, reduced DOC and S by 80% and 82% respectively, and normalized blood pressure. Nevertheless, the response to glucocorticoid was incomplete and an MRI was obtained, which revealed a right adrenal tumor. Post surgery, the patient promptly resumed menses and became normotensive. This case illustrates that ACTH and DEX cannot reliably differentiate tumor from hyperplasia, whereas the simultaneous increase of delta 4 and delta 5 steroids, present here, may favor a tumor. This case also allows speculation that the hypersecretion of DOC may result from inhibition of 11 beta-hydroxylase activity by excess androgens. The importance of appropriate imaging for diagnosis is underscored.

Adenoma↗

PubMedDate not supplied

Screening for refractive errors, strabismus and other ocular anomalies from ages 6 months to 3 years.

There were 3,375 children between the ages of 6 months and 3 years screened for refractive errors and strabismus. In 363 children (10.7%) some kind of pathology was detected. We suggest that continued efforts should be made to lower the age of detection of defects in vision.

Child, Preschool↗

PubMedDate not supplied

Medial rectus re-recession in undercorrected esotropia.

Conventional surgical management of surgically undercorrected esotropia includes bilateral lateral rectus resection, marginal myotomy, and Faden operation. During a 3-year period, 10 patients with surgically undercorrected esotropia had medial rectus re-recession 13.5 mm from the limbus. Successful binocular realignment (to 10 prism diopters or less residual binocular misalignment) was achieved in 9 of the 10 cases for both near and distance measurements.

Adolescent↗

PubMedDate not supplied