Corneal lamellar dissection by using suture threads in porcine eyes

PURPOSE: Lamellar dissection is one of the most delicate maneuvers in corneal surgery. We describe a new method that uses Ferrara ring instrumentation. METHODS: A 360 degrees tunnel is created at half of the stromal depth in porcine corneas. A suture (nylon 6-0 or Vicryl 6-0) was passed through the tunnel by using the Ferrara spatula. By means of alternate traction on the end of the suture thread, complete lamellar dissection was achieved. RESULTS: Light microscopy examination of the cornea confirmed that the dissection had a constant thickness and dissection depth. Scanning electron microscopy showed a homogeneous stromal surface without irregularities. CONCLUSIONS: This technique permits a homogeneous and safe lamellar dissection, which may prove useful in specific surgical procedures of the cornea.     

Activation of mesocorticolimbic reward circuits for assessment of relief of ongoing pain: A potential biomarker of efficacy

Preclinical assessment of pain has increasingly explored operant methods that may allow behavioral assessment of ongoing pain. In animals with incisional injury, peripheral nerve block produces conditioned place preference (CPP) and activates the mesolimbic dopaminergic reward pathway. We hypothesized that activation of this circuit could serve as a neurochemical output measure of relief of ongoing pain. Medications commonly used clinically, including gabapentin and nonsteroidal anti-inflammatory drugs (NSAIDs), were evaluated in models of post-surgical (1 day after incision) or neuropathic (14 days after spinal nerve ligation [SNL]) pain to determine whether the clinical efficacy profile of these drugs in these pain conditions was reflected by extracellular dopamine (DA) release in the nucleus accumbens (NAc) shell. Microdialysis was performed in awake rats. Basal DA levels were not significantly different between experimental groups, and no significant treatment effects were seen in sham-operated animals. Consistent with clinical observation, spinal clonidine produced CPP and produced a dose-related increase in net NAc DA release in SNL rats. Gabapentin, commonly used to treat neuropathic pain, produced increased NAc DA in rats with SNL but not in animals with incisional, injury. In contrast, ketorolac or naproxen produced increased NAc DA in animals with incisional but not neuropathic pain. Increased extracellular NAc DA release was consistent with CPP and was observed selectively with treatments commonly used clinically for post-surgical or neuropathic pain. Evaluation of NAc DA efflux in animal pain models may represent an objective neurochemical assay that may serve as a biomarker of efficacy for novel pain-relieving mechanisms.     

An annotated checklist of the horse flies (Diptera: Tabanidae) of the Sinai Peninsula Egypt with remarks on ecology and zoogeography

During a 20-year survey we routinely collected Tabanidae in the Sinai resulting in a checklist of 22 species. We recorded 2 species for the Levant (Tabanus mordax Austen, 1911 and Tabanus gratus Loew, 1858), 4 species for Egypt (Nemorius irritans (Ricardo, 1901), Chrysops flavipes Meigen, 1804, Haematopota coronata Austen, 1908 and Haematopota pallens Loew, 1871), 5 species for the Sinai (Atylotus farinosus (Szilády, 1915), Tabanus arenivagusAusten, 1920, Tabanus autumnalis Linnaeus, 1761, Haematopota minusculaAusten, 1920 and Dasyrhamphis nigritus Fabricius, 1794) for the first time and confirmed one doubtful record for the Sinai (Tabanus albifacies Loew, 1856). Furthermore we collected 10 more species that were previously known or could be presumed from the Sinai. The status of 4 species (Atylotus pallescens (Walker, 1871), Tabanus unifasciatus Loew, 1858, Tabanus politus (Walker, 1871) and Tabanus terminalis Walker, 1871) doubtfully recorded from the Sinai is discussed. For most of the 22 species, apart from zoogeographical notes, host and ecological observations are also given.