Lack of effect of a topical regenerative agent on re-epithelialization rate of canine spontaneous chronic corneal epithelial defects: A randomized, double-masked, placebo-controlled study.

Spontaneous chronic corneal epithelial defects (SCCEDs) are characteristic ulcers in dogs that are refractory to healing. The aim of the study was to evaluate the use of a topical regenerative agent to promote healing of SCCEDs. Nineteen dogs (20 eyes) were randomized to receive either regenerative agent (10 eyes) or placebo (10 eyes) every 48h following corneal debridement, which was repeated 1 week later if the SCCED had not yet healed. The mean±standard deviation time to re-epithelialization was 17.3±12.8 days for the group treated with a topical regenerative agent and 19.3±11.7 days for the group treated with a placebo; the cumulative healing rates were not statistically different (P>0.650). A positive association was found between the initial size of the ulcer and the time to re-epithelialization (r=0.555, P=0.011). Although well tolerated by dogs, there was no therapeutic advantage in using a topical regenerative agent for re-epithelialization of SCCEDs.

Parallel evolution of larval morphology and habitat in the snail-killing fly genus Tetanocera.

In this study, we sequenced one nuclear and three mitochondrial DNA loci to construct a robust estimate of phylogeny for all available species of Tetanocera. Character optimizations suggested that aquatic habitat was the ancestral condition for Tetanocera larvae, and that there were at least three parallel transitions to terrestrial habitat, with one reversal. Maximum likelihood analyses of character state transformations showed significant correlations between habitat transitions and changes in four larval morphological characteristics (cuticular pigmentation and three characters associated with the posterior spiracular disc). We provide evidence that phylogenetic niche conservatism has been responsible for the maintenance of aquatic-associated larval morphological character states, and that concerted convergence and/or gene linkage was responsible for parallel morphological changes that were derived in conjunction with habitat transitions. These habitat-morphology associations were consistent with the action of natural selection in facilitating the morphological changes that occurred during parallel aquatic to terrestrial habitat transitions in Tetanocera.

Acute posterior vitreous detachment: the predictive value of vitreous pigment and symptomatology.

AIM: To establish whether the presence of a retinal break can be predicted either by the presence of a positive Shafer's sign (pigment granules in the anterior vitreous) or symptomatology in patients presenting with an acute posterior vitreous detachment (PVD). METHODS: 200 eyes of 200 phakic patients with a symptomatic PVD of less than 1 month's duration underwent documentation of symptomatology and examination of the anterior vitreous for the presence of pigment granules. Indentation ophthalmoscopy was then carried out by an experienced vitreoretinal surgeon with no knowledge of the symptomatology or anterior vitreous gel examination findings. A second prospective group of 115 consecutive patients were assessed in a similar manner before primary rhegmatogenous retinal detachment repair. RESULTS: In 200 eyes presenting with an acute PVD, 25 were found to have an associated retinal break, 23 of which were also Shafer positive. In 115 eyes presenting for retinal detachment repair, 111 had an associated PVD and were found to be Shafer positive. Symptomatology was not predictive of an associated retinal break in the PVD group or in those presenting with a retinal detachment. CONCLUSION: The increased use of Shafer's sign is recommended as a valuable aid in determining which patients require urgent referral for an expert retinal examination. It is not possible to predict those patients with a retinal break secondary to PVD on the basis of symptomatology alone.

Dissociative identity disorder and pseudo-hysteria.

The diagnostic validity of dissociative identity disorder (DID) continues to inspire controversy, with some commentators claiming that DID is a modern variant of "hysteria"; that is, attention-seeking behavior. The author asserts that DID is indeed a valid psychiatric disorder, and believes that this skeptical reaction can largely be attributed to a specific set of transference/countertransference interactions that these patients tend to inspire. The paper delineates several clinical features of DID that can easily be mistaken for hysterical phenomena, and attempts to find the roots of this confusion in the DID patients' experience of interpersonal powerlessness, which leads them to present their symptoms in an unconvincing, "hysterical" manner. Confusion between the vertical split seen in the dissociative disorders and the horizontal split characteristic of the classic hysterical personality is discussed, as is the powerful effect of observer bias in creating hysterical-appearing phenomena. The term "pseudo-hysteria" is used to denote a situation in which a genuine psychiatric disorder, DID, is perceived as an hysterical production.

Data and simulation modeling to determine the estimated number of primary care beds in Oklahoma.

Growth in managed care has resulted in an increased need for studies in health care planning. The article focuses on the estimated number of primary care beds needed in the state to provide quality services to all Oklahoma residents. Based on the 1996 population estimations for Oklahoma and its distribution to the 77 counties, a space-filling approach is used to determine 46 service areas, each of which will provide primary care service to its area population. Service areas are constructed such that residents of an area are within an acceptable distance to a primary care provider in the area. A simulation model is developed to determine the number of primary care beds needed in each service area. Statistical analysis on actual hospital data is used to determine the distributions of inpatient flow and length of stay. The simulation model is validated for acute care hospitals before application to the service areas. Sensitivity analysis on model input parameter values is performed to determine their effect on primary care bed calculations. The effect of age distribution on the bed requirement is also studied. The results of this study will assist the Oklahoma Health Care Authority in the development of sound health care policy decisions.

Posttraumatic stress disorder in hospitalized adolescents: psychiatric comorbidity and clinical correlates.

OBJECTIVE: To describe the diagnostic comorbidity and clinical correlates of posttraumatic stress disorder (PTSD) in adolescent psychiatric inpatients. METHOD: Seventy-four adolescent inpatients were given a structured diagnostic interview, the revised version of the Diagnostic Interview for Children and Adolescents, and a battery of standard self-report measures to assess general trauma exposure, posttraumatic stress symptoms, suicidal behavior, dissociation, and depression. RESULTS: Ninety-three percent of subjects reported exposure to at least one traumatic event such as being a witness/victim of community violence, witnessing family violence, or being the victim of physical/sexual abuse. Thirty-two percent of subjects met diagnostic criteria for current PTSD, with sexual abuse cited as the most common traumatic stressor in 69% of PTSD cases. Girls were significantly more likely to develop PTSD than boys, although the total number of types of trauma did not differ by gender. Compared with psychiatric controls, male youngsters with PTSD were significantly more likely to have comorbid diagnoses of eating disorders, other anxiety disorders, and somatization disorder. Furthermore, male and female youngsters with PTSD were significantly more likely to have attempted suicide and report greater depressive and dissociative symptoms. CONCLUSION: In clinical populations of hospitalized adolescents exposed to multiple forms of trauma, PTSD is a common, but highly comorbid disorder. Specific multimodal assessments and treatments targeted to both PTSD and its comorbidity profile are warranted.

Dissociative symptomatology and aggressive behavior.

The present study examined the relationship between dissociative symptomatology and a range of aggressive behavior in a general psychiatric outpatient population. Of the total sample (n = 122), 29% scored above 25 on the Dissociative Experiences Scale (DES). Patients with high DES scores (> 25) were significantly more likely than patients with lower DES scores (< 25) to report a history of childhood sexual abuse, to have attempted suicide, and to report more assaultive behavior, irritability, and negativism. There were no differences between the patients with high versus low DES scores on homicidal behavior. To better manage and treat outpatients with dissociative symptomatology, it is important to clarify the association between outwardly aggressive behavior and dissociative experiences.

Midge larvae (Diptera: Chironomidae) as indicators of postmortem submersion interval of carcasses in a woodland stream: a preliminary report.

Data on colonization of rat carcasses by aquatic insects in riffle and pool areas of a small woodland stream were obtained to elucidate patterns potentially useful for determining the postmortem submersion interval of corpses in flowing water habitats. After 39 days, the carcasses had no visual signs of deterioration in the absence of large scavenging animals. Midge larvae (Diptera: Chironomidae) were the dominant insects colonizing the carcasses. No patterns in numbers of larvae over time were evident, but the diversity of genera increased after 29 days in the riffle. Also, Orthocladius larvae did not begin to colonize the carcasses until after 13 days of submersion in the riffle and after 20 days of submersion in the pool. Although separated only by 20 m, the riffle and pool rats had dissimilar faunal assemblages. This suggests that different indices for determining the postmortem submersion interval of corpses based on midge larvae colonization should be developed for these two habitats. This investigation does not provide replicated data, but does shed light on what may happen to mammalian carcasses placed in a stream at a particular time of the year.

Interferon alfa-associated retinopathy.

Interferon alfa and its related compounds have been used for more than 10 years in the treatment of a number of conditions including viral illnesses, childhood hemangiomas, various cancers, and leukemia. The potential applications for this class of medication continue to grow. The use of interferon alfa in experimental protocols has also increased, thus making it more likely that new indications will be discovered. It is probable that primary care physicians will be called on to initiate therapy or will see patients being treated with interferon in their practice. We report the development of interferon-related retinopathy in a 43-year-old man while he was receiving experimental treatment with interferon alfa for hepatitis B virus and hepatitis C virus infection. The vision loss was acute and only partially reversible. Interferon, its mechanism of action, and the past literature are briefly discussed.

'Spontaneous' hypertensive episodes with monoamine oxidase inhibitors.

Hypertensive reactions occurred without obvious cause in two patients receiving monoamine oxidase inhibitors (MAOIs) while being monitored in a hospital. These patients appear to have experienced "spontaneous" hypertensive episodes temporally related to the ingestion of the MAOIs. Similar occurrences in outpatients reported in the literature are reviewed.

PEARL II: portable laboratory computer system for psychophysiological assessment using event related brain potentials.

The PEARL II portable laboratory computer integrates hardware and software to serve as an on-line, realtime, experimental control and data acquisition system. Although the system can be used in many areas of research, PEARL II development has emphasized investigation of physiological responses from human subjects performing complex experimental tasks. PEARL functions as a "turn-key" system which performs standard neurological tests that would be employed, for example in neurotoxicological assessment. The PEARL system also includes several psychophysiological tests used in human engineering research on performance workload assessment. PEARL can also serve as a tool in basic research on human psychophysiology. The special feature of the PEARL test battery is its suitability for the measurements of event-related brain potentials (ERPs) in these tasks, although other physiological indices such as heart rate may be monitored. In addition, the PEARL system includes a versatile library of laboratory control subroutines that can be used to develop new applications.

Calcareous septa formed in snail shells by larvae of snail-killing flies.

Larvae of 13 species of Pherbellia and Colobaea that feed in exposed aquatic snails uitilize a product of the Malpighian tubules before they pupate to form a plate-like structure within the shell or to reinforce the anterior end of the puparium. The substance is partly calcium carbonate, and carbonic anhydrase may be involved in its production.