ABSTRACT
Tooth replacement rates of polyphyodont cartilaginous and bony fishes are hard to determine because of a lack of obvious patterning and maintaining specimens long enough to observe replacement. Pulse-chase is a fluorescent technique that differentially colours developing mineralized tissue. We present in situ tooth replacement rate and position data for the oral and pharyngeal detentions of Ophiodon elongatus (Pacific lingcod). We assessed over 10 000 teeth, in 20 fish, and found a daily replacement rate of about two teeth (3.6% of the dentition). The average tooth is in the dental battery for 27 days. The replacement was higher in the lower pharyngeal jaw (LPJ). We found no difference between replacement rates of feeding and non-feeding fish, suggesting feeding was not a driver of tooth replacement. Lingcod teeth have both a size and location fate; smaller teeth at one spot will not grow into larger teeth, even if a large tooth nearby is lost. We also found increased rates of replacement at the posterior of the LPJ relative to the anterior. We propose that lingcod teeth do not migrate in the jaw as they develop; their teeth are fated in size and location, erupting in their functional position.
Subject(s)
Perciformes , Tooth , Animals , Dentition , Jaw , OdontogenesisABSTRACT
Scabies is a common infestation for patients of all ages throughout the world. One of the standard therapies for scabies is 1% lindane lotion. Lindane has been associated with neurotoxic reactions, specifically seizures. We describe a case of a middle-aged adult man with human immunodeficiency virus (HIV) infection who was found to have typical scabies and was treated with a single topical application of lindane. Two hours after the application, the patient experienced a new-onset generalized seizure. We believe that the triad of HIV infection, medications that reduce seizure thresholds, and percutaneous absorption factors, in the aggregate, induced the seizure. We believe that lindane should not be prescribed for patients with HIV infection.
Subject(s)
HIV Seropositivity/complications , Hexachlorocyclohexane/adverse effects , Scabies/drug therapy , Seizures/chemically induced , Administration, Topical , Adult , Animals , Chlorpromazine/metabolism , Chlorpromazine/pharmacology , Dogs , Drug Interactions , Hexachlorocyclohexane/metabolism , Hexachlorocyclohexane/therapeutic use , Humans , Male , Scabies/complications , Seizures/etiology , Skin AbsorptionABSTRACT
Four black children with Spitz nevi are presented. The initial clinical diagnosis was pyogenic granuloma for three patients. One child had two Spitz nevi. Histologic examination revealed melanocytic dendritic hyperplasia in all cases.
