Anterior stromal puncture for recurrent erosion: further experience and new instrumentation

Anterior stromal puncture has recently been proposed as a new treatment for recalcitrant cases of recurrent corneal erosion. Concerns about the risks of corneal perforation and scarring, as well as doubts regarding its efficacy have prevented many patients from benefiting from this procedure. We introduce a new, inexpensive, commercially available instrument designed to standardize this technique, minimize scarring, and prevent corneal perforation. In a clinical trial involving 25 consecutive patients with recurrent erosions resistant to vigorous conservative treatment, the first 11 patients underwent stromal puncture in which a straight tuberculin needle was used; the following 14 were treated with a newly designed prototype needle. All patients in this series remained free of erosions after completion of stromal puncture, except for one woman with marked diffuse anterior basement membrane dystrophy, who went on to develop spontaneous bilateral erosions. Follow-up ranged from 2 months to 30 months (mean, 13 months). There were no complications of stromal puncture, and subjective and objective evaluations revealed no significant postoperative glare. Microscopic analysis of eye bank eyes subjected to anterior stromal puncture procedures demonstrated that the new prototype needle provided shallower penetration and thus less likelihood of perforation or excessive scarring than the straight needle. Also, postoperative discomfort and scarring appeared to be significantly less in patients treated with the prototype needle.     

Malignant melanoma associated with melanocytoma of the optic disc

A 61-year-old white man underwent enucleation because of progressive growth of a pigmented epipapillary tumor that was diagnosed 9 years earlier as an optic nerve and juxtapapillary melanocytoma. Histopathologic studies showed the tumor was a malignant melanoma of the optic disc and juxtapapillary retina and choroid. Foci of typical melanocytoma cells were within the tumor. The tumor produced segmental atrophy of the optic nerve. This is a rare example of a malignant melanoma developing in conjunction with a lesion that possessed typical clinical and histopathologic features of a melanocytoma of the optic disc.     

Effects of regional striatal lesions on motor, motivational, and executive aspects of progressive-ratio performance in rats.

The striatum is implicated in response selection and performance, the dorsal striatum in sensorimotor control and habit learning, and the ventral striatum in motivation and rewarded behaviors. Ventral striatal lesions produce performance changes on food-reinforced, progressive-ratio (PR) schedules, but the effects of dorsal striatal lesions on this task are not known. In this study, neither medial nor lateral dorsal striatal lesions produced deficits on the main motivational indices of PR performance. In contrast, significant impairments were observed in motoric or "executive" aspects of performance. Motivationally related manipulations of the task (food deprivation and reward magnitude) produced some subtle lesion-specific changes in behavior on these motoric or executive aspects of performance. Findings are discussed in relation to the roles of the dorsal and ventral striatum in reward-related behaviors.     

1141610241Altered expression of HuR, an mRNA stabilizing protein, mediates aberrant Placenta Growth Factor (PlGF) expression in preeclampsia

Background:  Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods:  Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results:  Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions:  HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects.