Hemispheric lateralization of memory stages for discriminated avoidance learning in the chick

Memory formation following the one trial discriminated bead task in the chick falls into three stages (short-term, intermediate and long-term memory) that are defined by susceptibility to different classes of drugs. The stages show sharply timed offsets of sensitivity and loss at specific times after inhibition. Recall of the memory in the chick shows cyclical changes that differ in period between left and right hemispheres, and is marked by a series of brief windows of enhanced recall that recur with periods of about 16 and 25 min in the left and right hemispheres respectively. The timing of these 'retrieval events' corresponds, to a large extent, with the timing of the memory stages seen in the visual discrimination task. Here we examine the effects of left or right hemisphere injection of the main agents (glutamate, ouabain and anisomycin) that have been used to characterize the three stages of memory. We show that memory in the left hemisphere is largely responsible for performance at test and that processes involved in its consolidation generate the phases of memory.     

Recent trends in elderly suicide rates in a multi-ethnic Asian city

BACKGROUND: There are a few reports on the trends of elderly suicide rates in western countries but none from Asian countries. OBJECTIVES: To describe the trends of elderly suicide rates of Chinese, Malays and Indians in Singapore from 1991 to 2000. DESIGN: Data obtained from the National Department of Statistics were used in the analysis of sex- and age-standardized suicide rates and relative risks. RESULTS: Overall, the suicide rates for the elderly showed a decline from 40.1 per 100,000 in 1990 to 17.8 per 100,000 in 2000, with the most pronounced decline occurring from 1995 to 2000. The suicide rate for elderly Chinese was at a peak of 52 per 100,000 in 1995 and declined to 20 per 100,000 in 2000. The rates for elderly Malays were consistently low at 2.2 per 100,000 for the 10 years; for elderly Indians the rates were between the other two ethnic groups. CONCLUSION: In the 10-year period, the elderly suicide rates in Singapore declined markedly, especially for elderly Chinese.     

Autograft Ossiculoplasty in Cholesteatoma Surgery: Is It Feasible?

OBJECTIVE: To investigate whether autologous ossicles can be safely used in ossicular reconstruction in cholesteatoma surgery after attempting cholesteatoma removal under the operating microscope. STUDY DESIGN: A prospective fine-section histological study of formalin-stored ossicles, harvested from cholesteatomatous ears, to evaluate for existence of residual cholesteatoma after surface disease clearance under the operating microscope. METHODS: One hundred four ossicles were harvested from 76 patients with cholesteatoma for the study. These malleus heads and includes were categorized into three groups: group 1, ossicles with retained shape and useful bulk, treated by microscopic stripping alone; group 2, ossicles with retained shape and useful bulk, treated by microscopic stripping and drilling; and group 3, badly eroded ossicles, treated by microscopic stripping alone. These treated ossicles were then subjected to 4 microm histopathological study. RESULTS: Residual disease was identified in 6 of the 104 ossicles. Residual disease was found only in badly eroded ossicles that are not suitable for reconstruction. All the usable ossicles were free of disease. CONCLUSIONS: Autologous ossicles that have retained body and bulk are safe to use for reconstruction after surface stripping under the operating microscope. Additional burring probably adds a further margin of safety.     

Renal angiomyolipoma with lymph node involvement: a case report and literature review

Renal angiomyolipomas (AMLs) are relatively common tumors containing fatty tissue, blood vessels, and muscular cells in various proportions. Typical AMLs can be diagnosed without histological confirmation by a combination of ultrasound and computed tomography imaging in up to 95% of cases. In contrast, simultaneous involvement of the kidney, renal vein, or lymph nodes is uncommon and might be confused with a metastasizing malignant tumor. We present a pathologically proven case of the very uncommon simultaneous involvement of the kidney and the lymph nodes in AML.     

Safety and patient experience with transtympanic electrocochleography

OBJECTIVES/HYPOTHESIS: Transtympanic electrocochleography (t-ECOG) is a sensitive diagnostic instrument used for Meniere's disease. It is sensitive by virtue of the recording electrode's position on the promontory of the cochlea where the signals are generated. There is concern about the invasive nature of t-ECOG in comparison to extratympanic recording techniques. The purpose of this study was to examine the safety issues, complications, and patient experience with t-ECOG. STUDY DESIGN: Observational study utilizing retrospective chart review and patient survey. METHODS: The medical records of 205 patients who underwent t-ECOG were reviewed for complications. Complications included persistent tympanic membrane perforation, hearing loss, otitis media, otitis externa, ear canal injury, hemotympanum, and pain. An additional 36 patients undergoing t-ECOG were surveyed on subjective measures such as pain during topical anesthesia of the tympanic membrane, during transtympanic placement of the needle electrode, and during the test procedure and overall experience with t-ECOG. RESULTS: There was one case of a nonhealed, persistent perforation in the setting of acute otitis media directly as a result of t-ECOG. Two patients developed otitis media, and three patients had ear pain for up to 5 days. All 36 patients felt the procedure to be tolerable with minimal discomfort. CONCLUSIONS: Transtympanic electrocochleography may be performed with good patient acceptance and infrequent complications.     

Macular translocation: unifying concepts, terminology, and classification

PURPOSE: To describe some unifying concepts, terminology, and classification of macular translocation so as to facilitate communication within the scientific community. METHODS: A panel of ophthalmologists with expertise in macular translocation reviewed available data and developed some unifying concepts, terminology, and classification of macular translocation. RESULTS: Macular translocation may be defined as any surgery that has a primary goal of relocating the central neurosensory retina or fovea intraoperatively or postoperatively specifically for the management of macular disease. It may be classified according to the size of the retinotomy and, where applicable, the technique of chorioscleral shortening used. The direction of macular translocation is denoted by the movement of the neurosensory macula relative to the underlying tissues. Effective macular translocation may be defined as successful intraoperative or postoperative relocation of the fovea overlying a subfoveal lesion to an area outside the border of the lesion. The concepts of minimum desired translocation and median postoperative foveal displacement can give some useful idea of the likelihood of effective macular translocation before surgery. CONCLUSIONS: Use of a common standardized terminology for macular translocation will facilitate communication within the scientific community and enhance further research in this area. However, the definitions, terms, classification, and concepts concerning macular translocation are likely to continue to evolve as macular translocation undergoes further modifications and refinements.     

The dental implications of chronic use of acidic medicines in medically compromised children

Objective: Liquid oral medicines form a significant proportion (11%) of the medicines used by the population as a whole, either prescribed or over the counter. The active agent, as well as some of the other ingredients, can pose a threat to oral health. Method: Eight liquid oral medicines and two effervescent preparations routinely prescribed for longterm use by paediatric renal patients were assessed for titratable acidity and pH values. Results: All of the medicines tested were acidic and the majority were well below the critical pH of 5.5 at which enamel demineralisation takes place. The titratable acidity values, at a pH of 6.7, ranged between 0.01 and 1.54 for the liquid preparations but were 8.4 and 10.6 for the two effervescent tablets tested. Conclusion: Surplus acid in effervescent preparations while ensuring palatability of medicines and thus compliance, may produce unwanted dental side effects in children who are already medically compromised.     

Circumdatin G, a new alkaloid from the fungus Aspergillus ochraceus

The crude extract of the broth of Aspergillus ochraceus was found to inhibit the final stage of polyprotein processing during hepatitis C virus replication. Bioassay-guided fractionation led to the isolation of the known compound mellein as the active component of the extract. Also isolated were circumdatin F and a new alkaloid, circumdatin G. The structure of circumdatin G was determined by spectroscopic analysis.