Masters of the manipulator: two new hypocrealean genera, Niveomyces (Cordycipitaceae) and Torrubiellomyces (Ophiocordycipitaceae), parasitic on the zombie ant fungus Ophiocordyceps camponoti-floridani.

During surveys in central Florida of the zombie-ant fungus Ophiocordyceps camponoti-floridani, which manipulates the behavior of the carpenter ant Camponotus floridanus, two distinct fungal morphotypes were discovered associated with and purportedly parasitic on O. camponoti-floridani. Based on a combination of unique morphology, ecology and phylogenetic placement, we discovered that these morphotypes comprise two novel lineages of fungi. Here, we propose two new genera, Niveomyces and Torrubiellomyces, each including a single species within the families Cordycipitaceae and Ophiocordycipitaceae, respectively. We generated de novo draft genomes for both new species and performed morphological and multi-loci phylogenetic analyses. The macromorphology and incidence of both new species, Niveomyces coronatus and Torrubiellomyces zombiae, suggest that these fungi are mycoparasites since their growth is observed exclusively on O. camponoti-floridani mycelium, stalks and ascomata, causing evident degradation of their fungal hosts. This work provides a starting point for more studies into fungal interactions between mycopathogens and entomopathogens, which have the potential to contribute towards efforts to battle the global rise of plant and animal mycoses. Citation: Araújo JPM, Lebert BM, Vermeulen S, et al. 2022. Masters of the manipulator: two new hypocrealean general, Niveomyces (Cordycipitaceae) and Torrubiellomyces (Ophiocordycipitaceae), parasitic on the zombie ant fungus Ophiocordyceps camponoti-floridani. Persoonia 49: 171-194. https://doi.org/10.3767/persoonia.2022.49.05.

Understanding workers' exposure: Systematic review and data-analysis of emission potential for NOAA.

Exposure assessment for nano-objects, and their aggregates and agglomerates (NOAA), has evolved from explorative research toward more comprehensive exposure assessment, providing data to further develop currently used conservative control banding (CB) tools for risk assessment. This study aims to provide an overview of current knowledge on emission potential of NOAA across the occupational life cycle stages by a systematic review and subsequently use the results in a data analysis. Relevant parameters that influence emission were collected from peer-reviewed literature with a focus on the four source domains (SD) in the source-receptor conceptual framework for NOAA. To make the reviewed exposure data comparable, we applied an approach to normalize for workplace circumstances and measurement location, resulting in comparable "surrogate" emission levels. Finally, descriptive statistics were performed. During the synthesis of nanoparticles (SD1), mechanical reduction and gas phase synthesis resulted in the highest emission compared to wet chemistry and chemical vapor condensation. For the handling and transfer of bulk manufactured nanomaterial powders (SD2) the emission could be differentiated for five activity classes: (1) harvesting; (2) dumping; (3); mixing; (4) cleaning of a reactor; and (5) transferring. Additionally, SD2 was subdivided by the handled amount with cleaning further subdivided by energy level. Harvesting and dumping resulted in the highest emissions. Regarding processes with liquids (SD3b), it was possible to distinguish emissions for spraying (propellant gas, (high) pressure and pump), sonication and brushing/rolling. The highest emissions observed in SD3b were for propellant gas spraying and pressure spraying. The highest emissions for the handling of nano-articles (SD4) were found to nano-sized particles (including NOAA) for grinding. This study provides a valuable overview of emission assessments performed in the workplace during the occupational handling of NOAA. Analyses were made per source domain to derive emission levels which can be used for models to quantitatively predict the exposure.

[Preventive dentistry 2. The force of habit and the change to -healthy oral behaviour]. / Preventieve tandheelkunde 2. De macht der gewoonte en de verandering naar gezond mondhygiënegedrag.

In a dental practice there are several situations where a change in behaviour of a patient is desirable or even necessary. It's not easy, however, to change someone's habits that they've had for many years, because these habits often give people a comfortable feeling. Change can lead to a decrease in self-confidence, which is why people are not always inclined to change. In order to realise a change in behaviour, there has to be an intrinsic motivation. An oral healthcare professional can increase the intrinsic motivation by using -Motivational Interviewing (MI). Communicating with compassion is the -basis for cooperation between a professional and his or her patient. -Motivating a patient takes less time and increases the chance of success.

Clinical spectrum of disease and outcomes in children with Omicron SARS-COV-2 infection in Cape Town, South Africa.

INTRODUCTION: Children with underlying comorbidities and infants are most severely affected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, including in low- and middle-income countries with a high prevalence of HIV and TB. We describe the clinical presentation of SARS-CoV-2 infection in children during the Omicron wave, in Cape Town, South Africa. METHODS: We analysed routine care data from a prospective cohort of children aged 0-13 years, with a positive SARS-CoV-2 real-time reverse-transcription polymerase chain reaction (rRT-PCR) or SARS-CoV-2 antigen test, admitted to Tygerberg Hospital between 1 November 2021 until 1 March 2022. Risk factors for severity of disease were assessed. RESULTS: Ninety-five children tested positive for SARS-CoV-2, of whom 87 (91.6%) were symptomatic. Clinical data were available for 86 children. The median age was 11 months (IQR 3.0-60.0), 37 (43.0%) were females, 21 (24.7%) were HIV-exposed and 7 (8.1%) were living with HIV (CLHIV). In total, 44 (51.2%) children had at least one underlying comorbidity. TB co-infection was seen in 11 children, 6 children were newly diagnosed and 5 children were already on TB treatment at the time of admission. CONCLUSION: There was no evidence of more severe disease in children living with HIV or TB.

INTRODUCTION: Les enfants et les nourrissons présentant des comorbidités sous-jacentes sont les plus gravement touchés par l'infection par le coronavirus-2 du syndrome respiratoire aigu sévère (SARS-CoV-2), y compris dans les pays à revenu faible ou intermédiaire où la prévalence du VIH et de la TB est élevée. Nous décrivons la présentation clinique de l'infection par le SARS-CoV-2 chez les enfants pendant la vague Omicron, au Cap, en Afrique du Sud. MÉTHODES: Nous avons analysé les données de soins de routine d'une cohorte prospective d'enfants âgés de 0 à 13 ans, avec un test positif de réaction en chaîne de la polymérase de transcription inverse en temps réel (rRT-PCR) ou d'antigène du SARS-CoV-2, admis à l'hôpital Tygerberg entre le 1er novembre 2021 et le 1er mars 2022. Les facteurs de risque de gravité de la maladie ont été évalués. RÉSULTATS: Quatre-vingt-quinze enfants ont été testés positifs au SARS-CoV-2, dont 87 (91,6%) étaient symptomatiques. Des données cliniques étaient disponibles pour 86 enfants. L'âge médian était de 11 mois (IQR 3,0­60,0), 37 (43,0%) étaient des filles, 21 (24,7%) étaient exposés au VIH et 7 (8,1%) vivaient avec le VIH (CLHIV). Au total, 44 (51,2%) enfants présentaient au moins une comorbidité sous-jacente. La co-infection par la TB a été observée chez 11 enfants, 6 enfants ont été nouvellement diagnostiqués et 5 enfants étaient déjà sous traitement antituberculeux au moment de l'admission. CONCLUSION: Il n'y a pas de preuve d'une maladie plus grave chez les enfants vivant avec le VIH ou la TB.

Heterogeneity in liquid shaken cultures of Aspergillus niger inoculated with melanised conidia or conidia of pigmentation mutants.

Black pigmented conidia of Aspergillus niger give rise to micro-colonies when incubated in liquid shaken medium. These micro-colonies are heterogeneous with respect to gene expression and size. We here studied the biophysical properties of the conidia of a control strain and of strains in which the fwnA, olvA or brnA gene is inactivated. These strains form fawn-, olive-, and brown-coloured conidia, respectively. The ΔolvA strain produced larger conidia (3.8 µm) when compared to the other strains (3.2-3.3 µm). Moreover, the conidia of the ΔolvA strain were highly hydrophilic, whereas those of the other strains were hydrophobic. The zeta potential of the ΔolvA conidia in medium was also more negative when compared to the control strain. This was accompanied by the near absence of a rodlet layer of hydrophobins. Using the Complex Object Parametric Analyzer and Sorter it was shown that the ratio of individual hyphae and micro-colonies in liquid shaken cultures of the deletion strains was lower when compared to the control strain. The average size of the micro-colonies of the control strain was also smaller (628 µm) than that of the deletion strains (790-858 µm). The size distribution of the micro-colonies of the ΔfwnA strain was normally distributed, while that of the other strains could be explained by assuming a population of small and a population of large micro-colonies. In the last set of experiments it was shown that relative expression levels of gpdA, and AmyR and XlnR regulated genes correlate in individual hyphae at the periphery of micro-colonies. This indicates the existence of transcriptionally and translationally highly active and lowly active hyphae as was previously shown in macro-colonies. However, the existence of distinct populations of hyphae with high and low transcriptional and translational activity seems to be less robust when compared to macro-colonies grown on solid medium.

Heterogeneity in the mycelium: implications for the use of fungi as cell factories.

Fungi are widely used as cell factories for the production of pharmaceutical compounds, enzymes and metabolites. Fungi form colonies that consist of a network of hyphae. During the last two decades it has become clear that fungal colonies within a liquid culture are heterogeneous in size and gene expression. Heterogeneity in growth, secretion, and RNA composition can even be found between and within zones of colonies. These findings imply that productivity in a bioreactor may be increased by reducing the heterogeneity within the culture. The results also imply that molecular mechanisms underlying productivity of fungi in bioreactors should not be studied at the culture level but at the level of micro-colony populations or even at zonal or hyphal level.

Multiomic interpretation of fungus-infected ant metabolomes during manipulated summit disease.

Camponotus floridanus ants show altered behaviors followed by a fatal summiting phenotype when infected with manipulating Ophiocordyceps camponoti-floridani fungi. Host summiting as a strategy to increase transmission is also observed with parasite taxa beyond fungi, including aquatic and terrestrial helminths and baculoviruses. The drastic phenotypic changes can sometimes reflect significant molecular changes in gene expression and metabolite concentrations measured in manipulated hosts. Nevertheless, the underlying mechanisms still need to be fully characterized. To investigate the small molecules producing summiting behavior, we infected C. floridanus ants with O. camponoti-floridani and sampled their heads for LC-MS/MS when we observed the characteristic summiting phenotype. We link this metabolomic data with our previous genomic and transcriptomic data to propose mechanisms that underlie manipulated summiting behavior in "zombie ants." This "multiomic" evidence points toward the dysregulation of neurotransmitter levels and neuronal signaling. We propose that these processes are altered during infection and manipulation based on (1) differential expression of neurotransmitter synthesis and receptor genes, (2) altered abundance of metabolites and neurotransmitters (or their precursors) with known behavioral effects in ants and other insects, and (3) possible suppression of a connected immunity pathway. We additionally report signals for metabolic activity during manipulation related to primary metabolism, detoxification, and anti-stress protectants. Taken together, these findings suggest that host manipulation is likely a multi-faceted phenomenon, with key processes changing at multiple levels of molecular organization.

Key factors underlying the willingness of patients with cancer to participate in medication redispensing.

BACKGROUND: Redispensing medication unused by patients to other patients could reduce the environmental burden of medication waste. Simultaneously, associated financial loss could be reduced, particularly for expensive medication such as oral anticancer drugs. An important determinant for successful medication redispensing is patient participation. OBJECTIVE(S): To identify key factors underlying the willingness of patients with cancer to participate in the redispensing of unused oral anticancer drugs. METHODS: Semi-structured interviews via telephone or video call were conducted with adult patients diagnosed with cancer from two Dutch hospitals. The interview guide was framed using the COM-B model for behavioural change, to elicit patients' capability, opportunity and motivation to participate in medication redispensing. Questions were related to patients' willingness to accept redispensed medication, reasons thereof, perceived concerns and needs. Inductive thematic analysis was applied. RESULTS: Seventeen patients (aged 38-82 years, 71% female), with nine different types of cancer participated. The majority of participants supported medication redispensing. Four categories of key factors underlying the willingness of patients with cancer to participate in medication redispensing were identified. First, the driver for participation was having positive societal impact, relating to affordability and sustainability of healthcare. Second, having trust in product quality was a requirement, influenced by preconceived beliefs, quality assurance and patients' knowledge of this process. Third, a facilitator for participating in medication redispensing was adequate provision of information. This concerned awareness of medication waste, information about medication redispensing, support from healthcare providers and other patients, and insight into medication dispensing history. Last, a convenient process for returning unused medication to pharmacies would facilitate participation in medication redispensing. CONCLUSIONS: The willingness of patients with cancer to participate in medication redispensing relates to a drive for achieving positive societal impact, provided that medication is of high quality, there is adequate information provision and a convenient process.

Challenges in qualitative social pharmacy research: Reflections based on a conference workshop.

A methodological debate within social pharmacy is ongoing regarding how to apply a qualitative approach. This paper emanates from a workshop at the Nordic Social Pharmacy Conference in 2019, named 'How do we know it's good? A workshop on quality criteria in qualitative social and clinical pharmacy research', that addressed this debate. The aim of this paper is twofold (1) to present the main key points raised during the workshop and (2) based on these inputs to contribute to the ongoing discussion on qualitative methodology within social pharmacy research. This paper starts with what was discussed at the workshop and further elaborated are some of the challenges with conducting qualitative research within social pharmacy. These include methodological and disciplinary competence and insecurity, reflections on the consequences of that many social pharmacy researchers come from a natural science background and how this (possibly) shapes the practice of qualitative research within the field. For example, how concepts like transparency and saturation, together with checklists and quality criteria are understood and used. Finally, we make suggestions for the next step for qualitative research in social pharmacy.

Effect of medication reconciliation on patient reported potential adverse events after hospital discharge.

BACKGROUND: Although medication reconciliation (MedRec) is effective in decreasing medication discrepancies, the effectiveness on Adverse Events (AEs) is very scarce. The objective of this study was to assess the effect of MedRec by a pharmacy team on patient-reported, potential AEs post-discharge. METHODS: This was a multicenter prospective intervention study with before-after design at two Dutch hospitals. Participants were patients aged ≥18 years admitted for more than 48 h using three or more prescription medications upon discharge. Patients in the control group received usual care. In the intervention period, a trained team of pharmacy staff executed medication reconciliation consisting of patient education upon admission and discharge, review of prescribed medication to identify errors, and information transfer to primary care. To address the primary outcome, the difference in proportion of patients with one or more potential AEs was measured by a structured telephone interview, two weeks after discharge between usual care and intervention group. To address the second outcome, the difference in median number of potential AEs per patient was calculated. Other outcomes assessed included the association between the intervention and patient characteristics. RESULTS: In total, 221 (138 usual care and 83 intervention) patients were included. The proportion of control and intervention patients with AEs was 88.4% and 86.7% respectively (p > 0.05). The median number of potential AEs per patient was lower in the intervention group compared with usual care (1.1 vs. 2.1, p < 0.0001). Being in the intervention arm was associated with less potential AEs (RR 0.5, 95% CI [0.4-0.6]), whereas being previously admitted was associated with a higher number of potential AEs (RR 1.3, 95% CI [1.1-1.5]). The effect of the intervention on the number of potential AE was stronger among women compared with men (p = 0.04). CONCLUSION: Although the intervention did not decrease the proportion of patients with AEs, a significant reduction in the median number of potential AEs after hospital discharge between the intervention and usual care group was observed.

Medication management during transitions from hospital to home: a focus group study with hospital and primary healthcare providers in the Netherlands.

Background Medication management is jeopardized during a patient's transition from hospital to home. Insight is required from both hospital and primary healthcare providers on how care should be organised to achieve continuity of medication management. Objective This study aimed to identify perspectives of hospital and primary healthcare providers on barriers to the continuity of medication management during a patient's transition from hospital to home and facilitators to overcome these. Setting A qualitative descriptive study was conducted within hospital and primary healthcare settings in the Netherlands. Method Two focus groups were performed with two community care registered nurses, two community pharmacists, four general practitioners, two hospital nurses, two hospital pharmacists, four outpatient pharmacists, two pharmacy technicians, and one physician. A semi-structured interview guide was used to identify perspectives of participants on barriers to continuity of medication management and facilitators to overcome these. Data were analysed following thematic content analysis. Main outcome measure Barriers to the continuity of medication management during a patient's transition from hospital to home would be enumerated, along with facilitators to overcome these barriers. Results Three main themes of barriers and facilitators were identified: (1) healthcare provider collaboration, including the transfer of medication information and effective collaboration; (2) patient's medication use, including information about medication, personalised care, and supervision after discharge; and (3) organisation of healthcare, including the connection between information systems and the supply of medication. Conclusion Barriers and facilitators to continuity of medication management during the transition from hospital to home occur at the provider, patient, and healthcare-system levels. Future interventions should focus on all levels through interprofessional healthcare teams, tailoring care to patient needs, and on the use of a uniform, nationwide patient electronic health record.

[Reducing medication waste; a challenge for care providers and society]. / Geneesmiddelverspilling verminderen.

Annually, in the Netherlands, at least 100 million euro is wasted on unused medication. This waste not only has considerable economic implications, but is also associated with an unnecessary burden on the environment and suboptimal care due to nonadherence to therapy. The reasons for medication wastage can be found throughout the entire pharmaceutical supply and use chain, which includes manufacturers, distributors/wholesalers, prescribers, pharmacists and patients, both in the community and hospital setting. A number of strategies are needed to minimize the waste of medication, one of which should be a preventative approach. Involvement of all stakeholders in the supply chain is a prerequisite for a successful outcome. It is important that prescribers are aware of the extent and consequences of wastage, and of the possible ways to reduce it.

Quantity and economic value of unused oral anti-cancer and biological disease-modifying anti-rheumatic drugs among outpatient pharmacy patients who discontinue therapy.

BACKGROUND: Patients sometimes discontinue the use of expensive oral anti-cancer drug (OACD) or biological disease-modifying anti-rheumatic drug (bDMARD) therapies early, leading to medication waste if the patient has not used all dispensed medication. OBJECTIVE: To determine the proportion of patients who have unused OACDs or bDMARDs after therapy discontinuation, and the quantity and economic value of these unused medications. Furthermore, patients' reasons for therapy discontinuation and their disposal method for unused medications were determined. METHODS: In a retrospective follow-up study using a Dutch outpatient pharmacy database, patients (≥18 years) who did not refill an OACD or bDMARD prescription, dispensed between November 2015 and February 2016, within two weeks of the prescription end date were contacted by phone and asked about their unused medication and reasons thereof. The economic value was calculated using Dutch medication prices. Data were descriptively analyzed in STATA13. RESULTS: The database included 1173 patients, of whom 159 likely had discontinued therapy and were contacted. Of these, 88 patients were excluded (39 refilled, 47 missing, and 2 other). Of the 71 patients who had discontinued therapy, 39 (54.9%) had unused medications, comprising 22 OACD users (mean age 63.0 (SD ±â€¯15.9) years, 50.0% female) and 17 bDMARD users (mean age 50.7 (SD ±â€¯13.5) years, 47.1% female). A total of 59 packages were unused, with a total value of €60,341. Unused OACD packages and bDMARD packages had median values of €179 (IQR €24-2487) and €992 (IQR €681-1093), respectively. Patients primarily discontinued therapy due to adverse or insufficient effects. CONCLUSIONS: This study illustrates that more than half of patients discontinuing OACD or bDMARD therapies have unused medication. This emphasizes the need for waste-reducing interventions.

Host cell-specific protein expression in vitro in Ehrlichia ruminantium.

Ehrlichia ruminantium, a tick-transmitted pathogen, is the causative agent of heartwater in ruminants. In this study, a proteomic approach was used to identify host cell-specific E. ruminantium proteins encoded by the map1 multigene family, expressed in vitro in bovine endothelial and tick cell cultures. Two-dimensional gel electrophoresis combined with mass spectrometry analysis was used to establish the identities of immunodominant proteins. Proteins extracted from E. ruminantium-infected endothelial cells were shown to be products of the map1 gene, whereas tick cell-derived E. ruminantium proteins were products of a different gene, map1-1. The expressed proteins were found to be glycosylated. Differential expression of MAP1 family proteins in vitro in mammalian and tick cell cultures indicates that the map1 multigene family might be involved in the adaptation of E. ruminantium to the mammalian host and vector tick.

[Satisfaction about physical appearance and teeth. Results of a nationwide study]. / Tevredenheid over lichaam en gebit. Resultaten van een landelijk onderzoek.

In a study involving a group of 907 randomly selected Dutch individuals, satisfaction about one's physical appearance and satisfaction about the appearance of one's teeth were assessed. Furthermore, the relationship between body esteem and happiness was explored. Three quarters of the respondents were satisfied about their physical appearance, while 70% was satisfied about the appearance of their teeth. Women and people with a non-Dutch background were significantly less likely to be satisfied about their physical appearance than men and those with a Dutch background. Individuals 30 years old and younger were more likely to be satisfied about their teeth than those who were older. Almost two third of the respondents (64%) reported that the appearance of their teeth contributed positively to their happiness. Women and people with a non-Dutch background were most likely to indicate that the appearance of their teeth contributed to their happiness. Satisfaction about general physical appearance and appearance of the teeth were significantly associated with happiness. Prospective studies are needed to examine to what extent esthetically motivated dental treatments make people happy and enhance their general well-being.

Patient and medication factors associated with preventable medication waste and possibilities for redispensing.

Background Knowledge on factors related to preventable medication waste and waste-reducing interventions, including redispensing unused medications, is needed to maximise effectiveness. Objective To assess patient and medication factors associated with preventable medication waste and possibilities for redispensing unused medications. Setting Dutch community pharmacies. Methods In this cross-sectional study, pharmacy-staff registered patient and medication characteristics of prescription medications returned to 41 Dutch community pharmacies during 1 week in 2014. Medications were classified as preventable waste if the remaining amount could have been prevented and as theoretically eligible for redispensing if the package was unopened, undamaged and ≥ 6 months until the expiry date. Associations were analysed using multivariate logistic regression. Main outcome measures Proportion of medications classified as preventable waste and as eligible for redispensing, including factors associated with these medications. Results Overall, 279 persons returned 759 (low-cost) medications, and 39.3% was classified as preventable waste. These medications were more frequently used by men than women (OR; 1.7[1.2-2.3]) and by older (> 65 years) than younger patients (OR; 1.4[1.0-2.0]). Medications dispensed for longer periods were more often unnecessary wasted (1-3 months OR; 1.8[1.1-3.0], > 3 months 3.2[1.5-6.9]). Of all returned medications, 19.1% was eligible for redispensing. These medications were more frequently used by men than women (OR; 1.9[1.3-2.9]). Medications chronically used were more frequently eligible for redispensing than acute use (OR; 2.1[1.0-4.3]), and used for longer periods (1-3 months OR; 4.6[2.3-8.9], > 3 months 7.8[3.3-18.5]). Conclusions Over one-third of waste due to medications returned to community pharmacies can be prevented. One-fifth of returned medications can be redispensed, but this seems less interesting from an economic viewpoint.

From So Simple a Beginning: The Evolution of Behavioral Manipulation by Fungi.

Parasites can manipulate the behavior of their hosts in ways that increase either their direct fitness or transmission to new hosts. The Kingdom Fungi have evolved a diverse array of strategies to manipulate arthropod behavior resulting in some of the most complex and impressive examples of behavioral manipulation by parasites. Here we provide an overview of these different interactions and discuss them from an evolutionary perspective. We discuss parasite manipulation within the context of Niko Tinbergen's four questions (function, phylogeny, causation, and ontogeny) before detailing the proximate mechanisms by which fungi control arthropod behavior and the evolutionary pathways to such adaptations. We focus on some systems for which we have recently acquired new knowledge (such as the zombie ant fungus, Ophiocordyceps unilateralis s.l.), but a major goal is also to highlight how many interesting examples remain to be discovered and investigated. With this in mind, we also discuss likely examples of manipulated spiders that are largely unexplored ("zombie spiders"). Armed with advanced tools in evolutionary biology (from serial block face SEM to RNAseq) we can discover how the fungi, a group of microbes capable of coordinated activity, have evolved the ability to direct animal behavior. In short, we have the ability to understand how the organism without the brain controls the one with the brain. We hope such a goal, coupled with the knowledge that many diverse examples of control exist, will inspire other organismal biologists to study the complex adaptations that have arisen from "so simple a beginning."

Histological comparison of corneal ablation with Er:YAG laser, Nd:YAG optical parametric oscillator, and excimer laser.

PURPOSE: To use histological techniques to assess and compare the ablation depth, local damage, and surface quality of corneal ablations by a Q-switched Er:YAG laser, an optical parametric oscillator laser at 2.94 microm, a long pulse Er:YAG laser, and a 193-nm excimer laser. METHODS: Human cadaver eyes and in vivo cat eyes were treated with a 6.0-mm diameter, 30-microm-deep phototherapeutic keratectomy ablation and a 6.0-mm diameter, -5.00-D photorefractive keratectomy ablation. Human cadaver eyes were also treated with a 5.0-mm diameter, -5.00-D laser in situ keratomileusis (LASIK) ablation. Fluences and pulse widths used were 200 mJ/cm2 and 70 ns for the Q-switched Er:YAG, 150 mJ/cm2 and 7 ns for the optical parametric oscillator laser (OPO), 500 mJ/cm2 and 50 microseconds for the long pulse Er:YAG, and 160 mj/cm2 and 20 ns for the excimer laser. In the ablation rate study, 12 porcine eyes were ablated by the OPO laser with a range of layers and at different fluences ranging from 60 to 150 mJ/cm2, all using a 1.5-mm spot on the eye. The ablation depth of these acute ablations was evaluated by light microscopy examination. RESULTS: In the acute damage study, light microscopy showed a thin surface layer in all samples with minimal thermal damage except on the long pulse Er:YAG corneas. Transmission electron microscopy revealed less than 0.3-microm surface damage for all specimens of both the optical parametric oscillator and the excimer laser samples with no evidence of collagen shrinkage. Transmission electron microscopy showed damage layers of 0.5 to 3 microm for Q-switched Er:YAG and 3 to 10 microm for long pulse Er:YAG. Scanning electron microscopy showed smooth surfaces in all eyes, although the excimer was the roughest. In the porcine eye study, ablations were produced in both PTK and PRK modes with the ablation rate per layer increasing with the fluence. At 120 mJ/cm2, the average ablation rate was 1.9 microm per layer. CONCLUSIONS: The histology from the short pulse mid-infrared optical parametric oscillator laser at 2.94 microm was comparable to the 193-nm excimer with a smooth, damage-free, ablation zone when performing PRK and LASIK.

Healing after photorefractive keratectomy in cat eyes with a scanning mid-infrared Nd:YAG pumped optical parametric oscillator laser.

PURPOSE: To evaluate the healing characteristics of cat corneas treated with a new scanning mid-infrared laser system. METHODS: Six adult cats were treated with 6-mm diameter photorefractive keratectomy (PRK) corrections. One eye in each animal was untreated as a control and the other was treated with either a -3.00 or -6.00 diopter ablation. The laser was a new Nd:YAG pumped optical parametric oscillator laser at 2.94 microm with a new scanning delivery system. The pulse width was 7 nanoseconds, the repetition rate was 10 Hz, the size of the laser spot on the eye was 1.0 mm, and the fluence was 150 mJ/cm2. Healing of the cat corneas was followed for 4 months. Slit-lamp and corneal topography evaluations were done at each follow-up examination. Histology was performed at the end of the study. RESULTS: The corneal epithelium healed within 1 week. There was no stromal haze in any eye after the epithelium healed. After the first 2 weeks, slit-lamp examination could not identify which eye was treated. Corneal topography showed corneal flattening. Light microscopy at 4 months revealed normal epithelium and increased keratocyte density in the anterior third of the cornea. Electron microscopy showed discontinuities in the basement membrane and hemidesmosomes. The deep stroma and endothelium were normal. CONCLUSIONS: Cat corneas treated with the new optical parametric oscillator laser healed normally with no adverse effects. Increased keratocyte activity in the anterior stroma was the only noticeable response besides the flattening shown by topography.

Plasma catecholamine and serum gastrin concentrations during sham feeding.

Plasma adrenaline, plasma noradrenaline and serum gastrin concentrations were measured before and after sham feeding in eight patients with duodenal ulcer and in four normal subjects. No significant change in the concentrations was observed after sham feeding. In three patients with duodenal ulcer an insulin test resulted in a 25-fold rise in plasma adrenaline. The ulcer patients showed significantly higher levels of plasma adrenaline and plasma noradrenaline than the normal subjects both before and after sham feeding, and this difference was probably not caused only by age difference in the two groups. It is concluded that sympathetic nervous activity and serum gastrin concentrations are not influenced by sham feeding in contrast to the influence of insulin hypoglycemia.