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1.
PLoS One ; 18(8): e0290065, 2023.
Article in English | MEDLINE | ID: mdl-37590251

ABSTRACT

Organizational climate is a key determinant of diverse aspects of success in work settings, including in academia. Power dynamics in higher education can result in inequitable experiences of workplace climate, potentially harming the well-being and productivity of employees. Quantifying experiences of climate across employment categories can help identify changes necessary to create a more equitable workplace for all. We developed and administered a climate survey within our academic workplace-the Department of Zoology and Physiology at the University of Wyoming-to evaluate experiences of climate across three employment categories: faculty, graduate students, and staff. Our survey included a combination of closed-response (e.g., Likert-scale) and open-ended questions. Most department members (82%) completed the survey, which was administered in fall 2021. Faculty generally reported more positive experiences than staff. Graduate students often fell between these two groups, though in some survey sections (e.g., mental health and well-being) students reported the most negative experiences of departmental climate. Three common themes emerged from the analysis of open-ended responses: equity, community, and accountability. We discuss how these themes correspond to concrete action items for improving our departmental climate, some of which have been implemented already, while others constitute future initiatives and/or require a collective push towards systemic change in academia. Finally, service work of this type often falls outside of job descriptions, requiring individuals to either work more or trade-off productivity in other areas that are formally evaluated. With the goal of minimizing this burden for others, we detail our process and provide the materials and framework necessary to streamline this process for other departments aiming to evaluate workplace climate as a key first step in building a positive work environment for all employees.


Subject(s)
Social Responsibility , Workplace , Humans , Climate , Drive , Faculty
2.
Ecol Evol ; 12(7): e9113, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35845385

ABSTRACT

Prior to the introduction of white-nose syndrome (WNS) to North America, temperate bats were thought to remain within hibernacula throughout most of the winter. However, recent research has shown that bats in the southeastern United States emerge regularly from hibernation and are active on the landscape, regardless of their WNS status. The relationship between winter activity and susceptibility to WNS has yet to be explored but warrants attention, as it may enable managers to implement targeted management for WNS-affected species. We investigated this relationship by implanting 1346 passive integrated transponder (PIT) tags in four species that vary in their susceptibility to WNS. Based on PIT-tag detections, three species entered hibernation from late October to early November. Bats were active at hibernacula entrances on days when midpoint temperatures ranged from -1.94 to 22.78°C (mean midpoint temperature = 8.70 ± 0.33°C). Eastern small-footed bats (Myotis leibii), a species with low susceptibility to WNS, were active throughout winter, with a significant decrease in activity in mid-hibernation (December 16 to February 15). Tricolored bats (Perimyotis subflavus), a species that is highly susceptible to WNS, exhibited an increase in activity beginning in mid-hibernation and extending through late hibernation (February 16 to March 31). Indiana bats (M. sodalis), a species determined to have a medium-high susceptibility to WNS, remained on the landscape into early hibernation (November 1 to December 15), after which we did not record any again until the latter portion of mid-hibernation. Finally, gray bats (M. grisescens), another species with low susceptibility to WNS, maintained low but regular levels of activity throughout winter. Given these results, we determined that emergence activity from hibernacula during winter is highly variable among bat species and our data will assist wildlife managers to make informed decisions regarding the timing of implementation of species-specific conservation actions.

3.
Sci Rep ; 12(1): 5688, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35383238

ABSTRACT

Studies examining the overwintering behaviors of North American hibernating bats are limited to a handful of species. We deployed temperature-sensitive transmitters on four species of bat that exhibit differences in their susceptibility to white nose syndrome (WNS; Myotis grisescens, M. leibii, M. sodalis, and Perimyotis subflavus) to determine if these differences are correlated with behavior exhibited during hibernation (i.e., torpor expression and arousal frequency). Mean torpor skin temperature (Tsk) and torpor bout duration varied significantly among species (P ≤ 0.024), but arousal Tsk and duration did not (P ≥ 0.057). One of the species with low susceptibility to WNS, M. leibii, had significantly shorter torpor bout durations (37.67 ± 26.89 h) than M. sodalis (260.67 ± 41.33 h), the species with medium susceptibility to WNS. Myotis leibii also had significantly higher torpor Tsk (18.57 °C ± 0.20) than M. grisescens (13.33 °C ± 0.60), a second species with low WNS susceptibility. The high susceptibility species, Perimyotis subflavus, exhibited low torpor Tsk (14.42 °C ± 0.36) but short torpor bouts (72.36 ± 32.16 h). We demonstrate that the four cavernicolous species examined exhibit a wide range in torpid skin temperature and torpor bout duration. Information from this study may improve WNS management in multispecies hibernacula or individual species management by providing insight into how some species may differ in their techniques for overwinter survival.


Subject(s)
Chiroptera , Hibernation , Torpor , Animals , Nose , Seasons
4.
Front Zool ; 18(1): 48, 2021 Sep 23.
Article in English | MEDLINE | ID: mdl-34556122

ABSTRACT

Temperate bat species use extended torpor to conserve energy when ambient temperatures are low and food resources are scarce. Previous research suggests that migratory bat species and species known to roost in thermally unstable locations, such as those that roost in trees, are more likely to remain active during winter. However, hibernating colonies of cave roosting bats in the southeastern United States may also be active and emerge from caves throughout the hibernation period. We report what bats are eating during these bouts of winter activity. We captured 2,044 bats of 10 species that emerged from six hibernacula over the course of 5 winters (October-April 2012/2013, 2013/2014, 2015/2016, 2016/2017, and 2017/2018). Using Next Generation sequencing of DNA from 284 fecal samples, we determined bats consumed at least 14 Orders of insect prey while active. Dietary composition did not vary among bat species; however, we did record variation in the dominant prey items represented in species' diets. We recorded Lepidoptera in the diet of 72.2% of individual Corynorhinus rafinesquii and 67.4% of individual Lasiurus borealis. Diptera were recorded in 32.4% of Myotis leibii, 37.4% of M. lucifugus, 35.5% of M. sodalis and 68.8% of Perimyotis subflavus. Our study is the first to use molecular genetic techniques to identify the winter diet of North American hibernating bats. The information from this study is integral to managing the landscape around bat hibernacula for insect prey, particularly in areas where hibernating bat populations are threatened by white-nose syndrome.

5.
Ecol Evol ; 7(5): 1487-1496, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28261459

ABSTRACT

Understanding the winter behavior of bats in temperate North America can provide insight into how bats react to perturbations caused by natural disturbances such as weather, human-induced disturbances, or the introduction of disease. This study measured the activity patterns of bats outside of their hibernaculum and asked how this winter activity varied by time, temperature, bat species, body condition, and WNS status. Over the course of three winters (2011-2013), we collected acoustic data and captured bats outside of five hibernacula in Tennessee, United States. During this time, Pseudogymnoascus destructans, the causative agent of white-nose syndrome, became established in hibernacula throughout the region, allowing us to track disease-related changes in the winter behavior of ten bat species. We determined that bats in the southeastern United States were active during winter regardless of disease. We recorded activity outside of hibernacula at temperatures as low as -13°C. Although bat activity was best determined by a combination of variables, the strongest factor was mean daily temperature (R2 = .2879, F1,1450 = 586.2, p < .0001). Bats that left the hibernacula earlier in evening had lower body condition than those that left 2-4 hr after sunset (F7,932 = 7.225, p < .0001, Tukey HSD, p < .05). The number of daytime emergences from hibernacula, as determined via acoustic detection, increased the longer a site was P. destructans positive (F3,17 808 = 124.48, p < .0001, Tukey HSD, p < .05). Through the use of passive acoustic monitoring and monthly captures, we determined that winter activity was driven by both ambient temperature and the presence of P. destructans.

6.
Vector Borne Zoonotic Dis ; 17(4): 243-246, 2017 04.
Article in English | MEDLINE | ID: mdl-28165925

ABSTRACT

Candidatus Bartonella mayotimonensis was detected in 2010 from an aortic valve sample of a patient with endocarditis from Iowa, the United States of America. The environmental source of the potentially new endocarditis-causing Bartonella remained elusive. We set out to study the prevalence and diversity of bat-associated Bartonella in North America. During 2015, mist nets and harp traps were used to capture 92 bats belonging to two species: little brown myotis (Myotis lucifugus Le Conte 1831, n = 73) and the gray myotis (M. grisescens A.H. Howell 1909, n = 19) in Kentucky, Michigan, Pennsylvania, and Tennessee. DNA preparations of peripheral blood samples from bats were subjected to a three-marker (gltA, rpoB, and intergenic spacer region [ISR]) multilocus sequence analysis. Sequence-verified gltA-positive PCR amplicons were obtained from nine samples. Three sequences were 99.7-100% identical with the gltA sequence of the Iowa endocarditis patient strain. Analysis of rpoB and ISR sequences demonstrated that one little brown myotis sample from the Upper Peninsula of Michigan contained Bartonella DNA, with 100% sequence identity with the Iowa endocarditis patient strain DNA. It appears possible that bats are a reservoir of Candidatus Bartonella mayotimonensis in North America.


Subject(s)
Bartonella Infections/veterinary , Bartonella/isolation & purification , Chiroptera/microbiology , Animals , Bartonella Infections/epidemiology , Bartonella Infections/microbiology , DNA, Bacterial/genetics , Prevalence , United States/epidemiology
7.
J Wildl Dis ; 52(4): 922-926, 2016 10.
Article in English | MEDLINE | ID: mdl-27434413

ABSTRACT

Pseudogymnoascus destructans, the causal agent of white-nose syndrome (WNS), is commonly found on bats captured both inside and outside caves during hibernation, a time when bats are most vulnerable to infection. It has not been documented in the southeast US on bats captured outside caves or on the landscape in summer. We collected 136 skin swabs from 10 species of bats captured at 20 sites on the Tennessee side of Great Smoky Mountains National Park, 12 May-16 August 2015. Three swabs were found positive for P. destructans, one from a male tricolored bat ( Perimyotis subflavus ) and two from male big brown bats ( Eptesicus fuscus ). This detection of P. destructans on free-flying male bats in the southeast US during summer has potential repercussions for the spread of the fungus to novel bat species and environments. Our finding emphasizes the need to maintain rigorous year-round decontamination of field clothing and equipment until more is understood about the viability of P. destructans found on bats captured outside hibernacula during summer, about the potential for males to act as reservoirs of the fungus, and the risk of fungal transmission and spread.


Subject(s)
Ascomycota/isolation & purification , Chiroptera/microbiology , Mycoses/veterinary , Animals , Ascomycota/pathogenicity , Hibernation , Male , Seasons , Tennessee
8.
J Chromatogr A ; 1418: 210-217, 2015 Oct 30.
Article in English | MEDLINE | ID: mdl-26422305

ABSTRACT

Method development for normal phase flash liquid chromatography traditionally employs preliminary screening using thin layer chromatography (TLC) with conventional solvents on bare silica. Extension to green flash chromatography via correlation of TLC migration results, with conventional polar/nonpolar liquid mixtures, and packed column supercritical fluid chromatography (SFC) retention times, via gradient elution on bare silica with a suite of carbon dioxide mobile phase modifiers, is reported. Feasibility of TLC/SFC correlation is individually described for eight ternary mixtures for a total of 24 neutral analytes. The experimental criteria for TLC/SFC correlation was assumed to be as follows: SFC/UV/MS retention (tR) increases among each of the three resolved mixture components; while, TLC migration (Rf) decreases among the same resolved mixture components. Successful correlation of TLC to SFC was observed for most of the polar organic solvents tested, with the best results observed via SFC on bare silica with methanol as the CO2 modifier and TLC on bare silica with a methanol/dichloromethane mixture.


Subject(s)
Chromatography, Supercritical Fluid/methods , Chromatography, Thin Layer/methods , Organic Chemicals/analysis , Carbon Dioxide/chemistry , Chromatography, Liquid , Feasibility Studies , Methanol/chemistry , Silicon Dioxide/chemistry , Solvents/chemistry
9.
J Wildl Dis ; 51(2): 519-22, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25647588

ABSTRACT

Pseudogymnoascus destructans, the causal agent of white-nose syndrome (WNS), is responsible for widespread mortality of hibernating bats across eastern North America. To document P. destructans exposure and infections on bats active during winter in the southeastern US, we collected epidermal swabs from bats captured during winters 2012-13 and 2013-14 in mist nets set outside of hibernacula in Tennessee. Epidermal swab samples were collected from eight Rafinesque's big-eared bats (Corynorhinus rafinesquii), six eastern red bats (Lasiurus borealis), and three silver-hair bats (Lasionycteris noctivagans). Using real-time PCR methods, we identified DNA sequences of P. destructans from skin swabs of two Rafinesque's big-eared bats, two eastern red bats, and one silver-haired bat. This is the first detection of the WNS fungus on Rafinesque's big-eared bats and eastern red bats and the second record of the presence of the fungus on silver-haired bats.


Subject(s)
Ascomycota/isolation & purification , Chiroptera , Dermatomycoses/veterinary , Animal Migration , Animals , Dermatomycoses/epidemiology , Dermatomycoses/microbiology , Female , Male , Species Specificity , Tennessee/epidemiology , Time Factors
10.
J Chromatogr A ; 1370: 240-5, 2014 Nov 28.
Article in English | MEDLINE | ID: mdl-25454148

ABSTRACT

Near baseline separation of ten sulfated sodium salts of various structurally related estrogens employing a variety of bonded stationary phase packed columns was obtained using a conventional supercritical fluid chromatograph coupled with UV detection. Critical pairs 2/3 (8,9-dehydroestrone/17ß-dihydroequilin) and 6/7 (17α-estradiol or 17α-dihydroequilin/estrone), however, failed to baseline separate. In all preliminary separations, 10mM ammonium acetate and variable percentages of H2O were initially used as co-additives in conjunction with methanol as a modifier. Different modifier programs and temperatures were employed to optimize the separation in a timely manner. A 2-ethylpyridine column provided the best separation compared to bare silica, diol, and cyano-based bonded phase columns. The employment of both salt and water as additives to the methanol-modified CO2 mobile phase suggested a mixed mode separation mechanism involving both ion pairing of each anionic sulfated estrogen with ammonium ion and hydrophilic interaction facilitated by partitioning of analyte between the aqueous solvated stationary phase and the aqueous component of the mobile phase. Upon more extensive study with either iso-propylamine or formic acid-ammonium formate buffer, the critical anionic pairs were 95% baseline resolved.


Subject(s)
Chromatography, Supercritical Fluid/methods , Estrogens/isolation & purification , Anions/chemistry , Chromatography, Supercritical Fluid/instrumentation , Estrogens/chemistry , Hydrophobic and Hydrophilic Interactions , Particle Size , Solubility , Sulfates/chemistry , Water/chemistry
11.
Med Teach ; 35(10): 815-9, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23758181

ABSTRACT

BACKGROUND: In the United States (U.S.), international medical graduates (IMGs) and American medical graduates (AMGs) confront work-related and adjustment challenges during post-graduate year one (PGY-1) of residency. AIM: To understand the challenges that IMGs and AMGs confronted during PGY-1 of a U.S. pediatric residency program from the perspective of the residents themselves. METHODS: A purposive sample of PGY-1, PGY-2, and PGY-3 residents participated in three semi-structured focus groups (N = 18). The data were analyzed inductively using a grounded theory approach to identify and verify emergent themes. RESULTS: IMGs confronted work-related and adjustment challenges during PGY-1 that included practicing medicine in the U.S., communicating with medical supervisors and nursing staff, communicating with patients, and relocating to the U.S. AMGs confronted work-related challenges that included medical decision-making and medical licensing. CONCLUSION: The work-related and adjustment challenges that IMGs and AMGs confronted during PGY-1 suggest that the culture of residency socializes IMGs and AMGs regarding professional expectations and responsibilities. Increased awareness of this socialization process among residency program directors, and interventions based on concrete recommendations, can help enhance PGY-1 for IMGs and AMGs across the medical specialties.


Subject(s)
Child Psychiatry/education , Foreign Medical Graduates , Internship and Residency/organization & administration , Organizational Culture , Socialization , Alabama , Communication , Decision Making , Evaluation Studies as Topic , Focus Groups , Humans , United States
12.
J Chromatogr A ; 1233: 85-90, 2012 Apr 13.
Article in English | MEDLINE | ID: mdl-22386258

ABSTRACT

Both analytical scale and preparative scale packed column supercritical fluid chromatography (SFC) have found widespread applicability for chiral separations of multiple polar pharmaceutical candidates. However, SFC is rapidly becoming an achiral technique. More specifically, ion pair SFC is finding greater utility for separation of ionic analytes such as amine salts and organic sulfonates. The key to this success is, in part, the incorporation of additives such as trifluoroacetic acid and ammonium acetate into the mobile phase in association with a wide variety of both bonded silica stationary phases and high purity bare silica. Ion pairing SFC coupled with evaporative light scattering detection and mass spectrometric detection is presented here for the separation of water soluble, uncapped, isomeric peptide pairs that differ in amino acid arrangement. The separation is best achieved on either diol-bonded silica or bare silica with 1-5% (w/w) water as a significant ingredient in the mobile phase. Nitrogenous stationary phases such as 2-ethylpyridine, which had been very successful for the separation of capped peptides failed to yield the desired separation regardless of the mobile phase composition. A HILIC type retention mechanism is postulated for the separation of both isomeric uncapped peptide pairs.


Subject(s)
Chromatography, Supercritical Fluid/methods , Peptides/isolation & purification , Amino Acid Sequence , Isomerism , Peptides/chemistry , Solubility , Water
13.
Biotech Histochem ; 87(4): 303-11, 2012 May.
Article in English | MEDLINE | ID: mdl-22250760

ABSTRACT

Adult adipose-derived mesenchymal stem cells (AD-MSC) are very interesting to our research group because they are easy to harvest, they are abundant in humans, and they have potential clinical applications in autologous cell therapy for disc degeneration. We examined these cells through sequential serial passages to assess osteogenic and chondrogenic capabilities, mean doubling time and cell senescence. Osteogenic and chondrogenic potencies were maintained through 13 passages. Mean passage doubling time increased significantly with increasing passage number. When donor age was evaluated, passages 1-4 from older donors had significantly longer doubling times compared to cells from younger donors. Passages 5-11 showed similar findings when analyzed by donor age. The mean percent senescence increased significantly with cell passaging, rising from 0% at passage 1 to 3.4% at passage 13. These novel data suggest that caution should be exercised when using AD-MSC with long passage times.


Subject(s)
Adipose Tissue/cytology , Mesenchymal Stem Cells/cytology , Adipose Tissue/chemistry , Adult , Aged , Cell Differentiation , Cellular Senescence , Chondrogenesis , Female , Humans , Middle Aged , Osteogenesis
14.
J Chromatogr A ; 1218(18): 2593-7, 2011 May 06.
Article in English | MEDLINE | ID: mdl-21439574

ABSTRACT

The characterization and determination of peptides is of great importance in the pharmaceutical industry as is the ability to rapidly perform targeted determinations of bioactive peptides in complex matrices. The purpose of the presented work is to assess the feasibility of packed column supercritical fluid chromatography (SFC) for the separation of two-pairs of water soluble peptides of identical mass, composition and charge that differ only in amino acid sequence. Upon evaluating a variety of conditions, trifluoroacetic acid (HTFA) in conjunction with methanol as the modifier proved to be, in general, the most successful mobile phase additive for elution of the two isomeric peptide pairs from all nitrogenous stationary phases. In contrast, water and ammonium acetate gave distorted peak shapes and therefore proved to be less satisfactory as neutral additives. The basic additive, iso-propylamine (IPAm), coupled with HA-Pyridine yielded the highest resolution factor for the complete study. Aminopropyl and HA-Pyridine columns with 5 µm particle size and 60 Å pore size were found to be best for resolution of each peptide pair. Bare silica and phenyl-hexyl stationary phases did not afford any separation. The primary roles of the carbon dioxide and methanol modifier are believed to provide (a) stationary phase solvation and (b) peptide solubility and transport; while, HTFA is postulated to fully protonate each peptide and form ion pairs between its conjugate base and cationic peptide analyte. The separation process, therefore, is best viewed as ion pair supercritical fluid chromatography (IP-SFC). For the case where IPAm gave good resolution on the HA-Pyridine column, the peptides are probably in the neutral state.


Subject(s)
Chromatography, Supercritical Fluid/methods , Peptides/isolation & purification , Chromatography, Supercritical Fluid/instrumentation , Isomerism , Particle Size , Peptides/chemistry , Porosity , Protein Multimerization , Pyridines/chemistry
15.
Arch Pediatr Adolesc Med ; 165(2): 126-33, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21300652

ABSTRACT

OBJECTIVE: To establish the limit between beneficial and futile management in the extremely preterm infant, born at the limit of viability, at 22 to 26 weeks of gestational age (GA). DESIGN: Retrospective study (11-year study period). SETTING: A tertiary regional neonatal unit. PARTICIPANTS: Inborn infants (n = 841) with a birth weight of 1000 g or less and GA 2207 through 2667 weeks. INTERVENTION: We compared mortality and neurodevelopmental outcome between 2 periods, epoch 1 (January 1998 to June 2003) and epoch 2 (July 2003 to December 2008). For neurodevelopmental data, epoch 2 extended only to December 2006. MAIN OUTCOME MEASURES: We reviewed survival rates and adverse neurodevelopmental outcome rates at 18 to 24 months' corrected age. RESULTS: In the past decade, survival rates continued to increase while neurodevelopmental impairment rates in the extremely preterm infant decreased. From epoch 1 to epoch 2, the increase in survival rate occurred in infants born at 22 weeks' estimated GA, from 20% to 40%, while the decrease in neurodevelopmental impairment (54% to 28%) and severe neurodevelopmental impairment (35% to 8%) occurred in infants born at 23 to 24 weeks' estimated GA. CONCLUSIONS: Novel and aggressive neonatal therapies continue to affect neonatal outcome, mainly in infants born at the limit of viability. Our data suggest that each center offer prospective parents an assessment of the limits of viability based on their updated outcome results.


Subject(s)
Developmental Disabilities/epidemiology , Gestational Age , Infant, Premature , Infant, Very Low Birth Weight , Intensive Care, Neonatal/standards , Female , Humans , Infant Mortality , Infant, Newborn , Male , Poisson Distribution , Retrospective Studies , Risk Factors , Survival Rate
16.
Phys Rev Lett ; 104(14): 142502, 2010 Apr 09.
Article in English | MEDLINE | ID: mdl-20481935

ABSTRACT

The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes (293)117 and (294)117 were produced in fusion reactions between (48)Ca and (249)Bk. Decay chains involving 11 new nuclei were identified by means of the Dubna gas-filled recoil separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z > or = 111, validating the concept of the long sought island of enhanced stability for superheavy nuclei.

17.
Pers Soc Psychol Bull ; 34(7): 1004-17, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18436654

ABSTRACT

This article demonstrates the validity and utility of conceptualizing narcissistic personality in terms of relative approach-avoidance motivation. Across three studies (N = 1,319), narcissism predicted high approach and low avoidance motivation. That is, narcissists reported being strongly motivated to approach desirable outcomes but only weakly motivated to avoid negative outcomes. Relative approach-avoidance motivation was shown to be useful in terms of explaining behavioral tendencies associated with narcissism (i.e., functional and dysfunctional impulsivity) and distinguishing different "flavors" of narcissism (i.e., overt and covert narcissism). Discussion focuses on how approach-avoidance motivation may be used to explain prior findings in the narcissism literature and generate novel future hypotheses.


Subject(s)
Avoidance Learning , Motivation , Narcissism , Adult , Female , Humans , Impulsive Behavior/psychology , Interpersonal Relations , Male , Personality Inventory , Social Behavior , Social Desirability
18.
Br J Ophthalmol ; 89(7): 841-6, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15965163

ABSTRACT

AIMS: To examine histopathological and immunohistochemical changes in lenticules and host of corneal buttons from patients who previously underwent epikeratoplasty for keratoconus. METHODS: 12 penetrating keratoplasty specimens from patients with keratoconus who had previously undergone epikeratoplasty, eight keratoconus, and seven normal corneas were examined. Immunostaining for Sp1, alpha1-proteinase inhibitor (alpha1-PI), and alpha2-macroglobulin (alpha2M) were performed. RESULTS: In nine of the 12 lenticules, the keratoconus-like disruptions were found in Bowman's layer. Peripheral and posterior keratocyte repopulation of the lenticules was observed in all cases. Keratocyte repopulation in the anterior and mid-stromal regions of the lenticules appeared related to the time since epikeratoplasty. Sp1 nuclear staining of the basal and wing epithelial cells was more intense in lenticules and keratoconus corneas than in normal corneas. Lenticular, host, and keratoconus keratocytes showed positive Sp1 staining, whereas staining was absent in normal corneas. Compared to normal corneas, alpha1-PI and alpha2M immunostaining was lower in the lenticules, host, and keratoconus specimens. CONCLUSIONS: The epithelial cells and keratocytes repopulated in the lenticules retain keratoconus-like biochemical abnormalities such as upregulation of Sp1 and downregulation of alpha1-PI and alpha2M. The authors speculate that both keratocytes and the corneal epithelium may participate in the development of keratoconus.


Subject(s)
Cornea/pathology , Corneal Transplantation/methods , Keratoconus/pathology , Adolescent , Adult , Cornea/immunology , Corneal Stroma/pathology , Epikeratophakia , Epithelial Cells/pathology , Epithelium, Corneal/pathology , Female , Humans , Immunohistochemistry , Keratoconus/immunology , Keratoconus/surgery , Male , Middle Aged , Sp1 Transcription Factor/analysis , alpha 1-Antitrypsin/analysis , alpha-Macroglobulins/analysis
19.
Cornea ; 20(5): 543-6, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11413416

ABSTRACT

PURPOSE: We report clinical and histopathologic findings of a conjunctival lesion associated with xeroderma pigmentosum. METHODS: A Saudi girl with known xeroderma pigmentosum presented with pain and photophobia of the right eye and an elevated temporally located perilimbal mass. RESULTS: The mass was resected successfully and has not recurred during 1-year follow-up. Histopathologic examination of the tissue showed a necrobiotic granuloma with associated histiocytic infiltration. The patient had no systemic disease, lipid was not detected in the histiocytic lesion, no Touton giant cells were present, and there was no evidence of elastolysis. CONCLUSION: Ocular malignancies occur in association with xeroderma pigmentosum, but benign lesions that mimic a malignancy may occur.


Subject(s)
Conjunctival Diseases/etiology , Granuloma/etiology , Necrobiotic Disorders/etiology , Xeroderma Pigmentosum/complications , Adolescent , Conjunctival Diseases/pathology , Conjunctival Diseases/surgery , Female , Granuloma/pathology , Granuloma/surgery , Histiocytosis/pathology , Humans , Necrobiotic Disorders/pathology , Necrobiotic Disorders/surgery , Xeroderma Pigmentosum/pathology , Xeroderma Pigmentosum/surgery
20.
Ophthalmology ; 108(3): 553-8, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11237910

ABSTRACT

OBJECTIVE: To describe three cases of squamous cell carcinoma of the conjunctiva presenting with corneal and scleral inflammation, thinning, and perforation without any tumor formation. DESIGN: Three case reports. PARTICIPANTS: Three male subjects aged 76, 66, and 61 years. INTERVENTION: The subjects had symptoms of external ocular inflammation with focal corneal or scleral thinning and inflammation, as well as interstitial keratitis in two cases. Initial diagnosis of sclerokeratitis with limbal thinning was made in all three in addition to a pterygium in case 2. MAIN OUTCOME MEASURES: Diagnosis of the carcinoma was delayed for 2 to 24 months in two cases, whereas case 2 was diagnosed on excision of a pterygium from the involved area. RESULTS: All subjects developed intraocular extension after further scleral thinning and perforation without tumefaction. CONCLUSIONS: Squamous cell carcinoma of the conjunctiva may be seen without a distinct mass and can masquerade as sclerokeratitis, scleromalacia, or interstitial keratitis. It seems that diffuse growth with inflammation leads to thinning, necrosis, and perforation of the ocular wall with resultant intraocular spread. Squamous cell carcinoma should be considered in the differential diagnosis of corneal and scleral thinning, perforation, and inflammation of unknown cause, especially in the older male subject.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , Conjunctival Neoplasms/diagnosis , Keratitis/diagnosis , Scleritis/diagnosis , Aged , Humans , Male , Middle Aged , Pterygium/diagnosis , Rupture, Spontaneous/diagnosis
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