A histopathologic study of macular cysts and holes

Forty-four eyes from 39 patients with either lamellar macular holes (17 eyes), full-thickness macular holes (18 eyes), and/or macular cysts (9 eyes) were studied histopathologically. Lamellar and full-thickness holes were frequently found in eyes with a history of trauma or ocular surgery. Diabetes mellitus was the most common condition associated with macular cysts. Four lamellar holes and four full-thickness holes occurred in eyes with senile macular degeneration. Six lamellar holes, eight full-thickness holes, and one macular cyst developed on an idiopathic basis. Residual cystoid macular edema was the most prevalent accompanying pathologic feature. Cystoid macular edema was also noted in the opposite eye in seven cases of lamellar and full-thickness holes. A preretinal glial membrane, thought to be a secondary change, was found at or near the edges of the lamellar or full-thickness holes or over the macular cyst in the majority of cases. Wrinkling of the internal limiting membrane (ILM) was present in five cases. Vitreous traction, with or without an operculum, was infrequently associated with these entities.     

GTP cyclohydrolase deficiency; intrafamilial variation in clinical phenotype, including levodopa responsiveness

Traditional Chinese drugs (TCDs) have played a key role for Chinese people in the treatment of diseases since ancient times. The use of TCDs has generated a great amount of information in the past thousand years about the relationship between natural products and the human body. However, up to now, our understanding on the mode of action of the TCD is still limited. Considering that the basic mechanism of all drug function involves the interaction between the drug and biological receptors at the molecular level, we propose to connect TCDs with modern medicine theory through molecular structures. We propose to explain functions of TCDs by using the knowledge developed in modern molecular biology, pharmacology, computer chemistry, and biochemistry. We are working on a computer-aided Chinese drug study that is discussed in this paper. A short introduction on the progress of our research is also given.     

Modification of a receptor-binding surface of epidermal growth factor (EGF): analogs with enhanced receptor affinity at low pH or at neutrality

Six mutants of human epidermal growth factor (EGF), which carry single point substitutions within a surface patch proposed to juxtapose the bound receptor, were prepared and characterized for receptor affinity and mitogenicity. Receptor affinities relative to EGF are G12Q > H16D > Y13W > Q43A approximately = H16A approximately = EGF >> L15A. Notably, the reduced receptor affinity of mutant L15A indicates that Leu15 probably contributes substantially to receptor binding whereas unaltered receptor affinities observed for analogs H16A and Q43A indicate that neither His16 nor Gln43 contributes significantly to this interaction. On the other hand, the observed enhanced receptor affinities of analogs G12Q, Y13W and H16D highlight surface loci where additional productive receptor-binding contacts can be introduced. Interestingly, at acidic pH analog H16A reveals substantially greater receptor affinity than that of EGF, a property which may offer enhanced therapeutic utility in acidic environments in vivo.      

Indications and outcomes of strabismus repair in visually mature patients

OBJECTIVE: To identify and examine the indications, outcomes and potential risks of strabismus surgery in visually mature patients. DESIGN: Case series. SETTING: University-based referral practice in Edmonton. PATIENTS: A total of 222 patients (115 females and 107 males) aged 9 to 69 (mean 29) years who underwent strabismus surgery for various types of strabismus (as grouped by original diagnosis). All patients were followed for at least 6 weeks postoperatively. OUTCOME MEASURES: Previous surgery and deviation in prism dioptres (delta) (distance and near), sensory status (measured by the Titmus stereotest at near) and the presence of symptoms (diplopia, abnormal head posture or asthenopia), recorded preoperatively, 6 weeks postoperatively and at the last postoperative visit. RESULTS: The patients were followed for an average of 14 months postoperatively. At the last postoperative visit 187 patients (84%) were aligned to within 15 delta of orthotropia. Overall, 116 patients (52%) demonstrated some degree of stereopsis postoperatively, compared with 78 (35%) preoperatively. A total of 116 patients (52%) had symptoms preoperatively, including diplopia, abnormal head posture or asthenopia; 88 (76%) of the 116 had complete resolution of their symptoms. Six patients (4%) without diplopia preoperatively were found to have this symptom postoperatively. CONCLUSIONS: The findings suggest that most visually mature patients under-going strabismus surgery can expect functional benefits, including improvement of alignment, preservation and occasionally restoration of sensory fusion, and elimination of diplopia, abnormal head posture and asthenopia.     

Chemically dependent doctors

Overcoming denial and admitting to having a chemical dependency problem is a hurdle that is extraordinarily difficult for anyone to handle without professional assistance. Addicted health care professionals often become even more deeply enmeshed in denial of their problem. They refuse help because they see themselves as educated beyond the level of those who are attempting to help them, and because they fear professional humiliation. Dental professionals who become aware of a colleague's chemical dependence, have an ethical duty to intervene in a constructive way. Reporting to a dental society wellness committee will accomplish this goal while protecting patients, the profession, the addicted provider, and the provider's family. Nonetheless, assisting chemically dependent colleagues to seek treatment can be an enormous burden. Thus, the dental hygienist in the case presented has few choices. She clearly has sufficient evidence of the dentist's chemical dependency problem and, ethically, she must act to prevent harm to patients. If a wellness program is available, it will help her. However, she should not expect gratitude from the dentist at the time of her intervention. Addicted persons rarely thank those who try to help them until much later and whistle-blowers are rarely appreciated. As is often the case, doing the right thing may be a challenge that risks losing a relationship or, as in the case presented, a job.