The socioeconomic impact of the COVID-19 lockdown on families affected by childhood respiratory illnesses in Cape Town, South Africa

The COVID-19 pandemic impacted families globally, directly and indirectly. Children presenting with respiratory illnesses are affected by emerging health systems and socioeconomic changes in the COVID-19 era. We explored the socioeconomic impacts of the COVID-19 lockdown on families with a respiratory illness diagnosed in their child in Cape Town, South Africa. This study was nested in a prospective observational cohort of children presenting with respiratory symptoms presumptive of COVID-19. We conducted 21 semi-structured interviews to explore the socioeconomic impact of the COVID-19 pandemic on families with a child affected by respiratory illnesses. We used case descriptive analysis and thematically organised common and divergent experiences. We found that socioeconomic challenges in low-income communities were exacerbated: 1) loss of pre-COVID sources of income (loss of income, employment and working hours), 2) shrinking employment opportunities due to business closures and strict preventative measures, 3) family network dependence to cope with financial pressures, 4) impact on education, implicating additional pressures due to lack of resources for adequate home schooling and 5) caregivers' mental health and wellbeing being impacted, causing stress and anxiety due to loss of income. This study shows that the COVID-19 lockdown impacted the socioeconomic aspects of families caring for a child with a respiratory illness. Care became more complicated and adversely impacted the family's emotional well-being and health-seeking behaviour. These impacts should be more carefully considered in order to strengthen health services and global health messaging in future pandemics.

How does post COVID differ from other post-viral conditions in childhood and adolescence (0-20 years old)? A systematic review

Background

Post Coronavirus disease (COVID) and other post-viral infection syndromes present an overlap of pathogenesis, onset, progression, and symptom profile. We aimed to systematically describe studies on post-viral conditions and determine the entity of post COVID compared to other post-viral conditions in children.

Methods

We conducted a systematic search of the Embase, MEDLINE, Cochrane Library, and GoogleScholar databases (January 1946-3 November 2023), according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The main outcomes were differences in condition duration, symptom type, and development of chronic symptoms. This systematic review was registered on PROSPERO (CRD42023401789).

Findings

35/5051 studies were included, with 42,934 children, adolescents and young adults (0-20 years old) overall. Twenty-eight studies focused on post COVID symptoms, followed by five papers on Respiratory Syncytial Virus (RSV) and Rhinovirus, one study on Epstein-Barr Virus (EBV), and one on gastrointestinal viruses. Studies on post COVID mainly reported data on older children/adolescents, describing long-lasting symptoms, including fatigue, neurologic, cardiorespiratory, musculoskeletal, mental health, and gastrointestinal symptoms. The maximum described symptoms duration was eighteen months, with an average follow-up of seven months. The development of chronic symptoms was reported by 30 studies (93.8%) for 10,473/28,474 patients (36.8%). Recovery was achieved in 18,001/28,474 cases (63.2%). The study on EBV reported persistent fatigue in adolescents for a similar duration (6 months, 46% chronic). Studies on RSV and Rhinovirus were mainly done in children under three years, with development of recurrent wheezing (up to 3 years).

Interpretation

Post-viral fatigue was a shared feature between post COVID and post EBV conditions. A better understanding of post COVID as a unique condition, sharing features with other post-viral syndromes, is needed. The healthcare burden and socio-economic consequences for children and their families warrant further investigation and development of appropriate healthcare management plans. The foremost requirement is the establishment of consistent and shareable definitions, as well as a consensus on outcomes, to effectively evaluate follow-up and quantify the burden of different viral infections.

Funding

EU Horizon, EDCTP, NIH.

Chronic lung disease in children due to SARS-CoV-2 pneumonia: Case series

The reported prevalence of chronic lung disease (CLD) due to coronavirus 2 (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2)]) pneumonia with the severe acute respiratory syndrome in children is unknown and rarely reported in English literature. In contrast to most other respiratory viruses, children generally have less severe symptoms when infected with SARS-CoV-2. Although only a minority of children with SARS-CoV-2 infection require hospitalization, severe cases have been reported. More severe SARS-CoV-2 respiratory disease in infants has been reported in low- and middle-income countries (LMICs) compared to high-income countries (HICs). We describe our experience of five cases of CLD in children due to SARS-CoV-2 collected between April 2020 and August 2022. We included children who had a history of a positive SARS-CoV-2 polymerase chain reaction (PCR) or antigen test or a positive antibody test in the serum. Three patterns of CLD related to SARS-CoV-2 were identified: (1) CLD in infants postventilation for severe pneumonia (n = 3); (2) small airway disease with bronchiolitis obliterans picture (n = 1) and (3) adolescent with adult-like post-SARS-CoV-2 disease (n = 1). Chest computerized tomography scans showed airspace disease and ground-glass opacities involving both lungs with the development of coarse interstitial markings seen in four patients, reflecting the long-term fibrotic consequences of diffuse alveolar damage that occur in children post-SARS-CoV-2 infection. Children with SARS-CoV-2 infection mostly have mild symptoms with little to no long-term sequelae, but the severe long-term respiratory disease can develop.

AB1554-HPR DRUG-RELATED PROBLEMS EXPERIENCED BY PATIENTS WITH RHEUMATIC DISEASES: A LONGITUDINAL OBSERVATIONAL STUDY

Background

Patients with rheumatic diseases can experience multiple drug-related problems (DRPs) along their patient journey.1 Insight into patients’ experience of DRPs over time might aid in timely identifying and preventing DRPs.2,3

Objectives

To longitudinally identify DRPs experienced by patients with rheumatic diseases.

Methods

A prospective observational study was conducted in a Dutch outpatient pharmacy. Adult patients with rheumatic diseases that were prescribed medication by a rheumatologist were questioned about experienced DRPs by telephone 4 times in 8 weeks using a structured interview-guide. Unique DRPs (i.e. DRPs not reported in earlier interviews by individuals) were categorized using a classification for patient-reported DRPs and analysed descriptively.

Results

In total, 52 participants (median age 68 years (interquartile range (IQR) 62-74), 52% male) completed 192 interviews with 45 (87%) participants completing all 4 interviews. The majority of patients (65%) were diagnosed with rheumatoid arthritis. Patients reported a median number of 3 (IQR 2-5) unique DRPs during interview 1. In subsequent interviews, patients reported median numbers of 1 (IQR 0-2), 1 (IQR 0-2) and 0 (IQR 0-1) unique DRPs for interview 2 to 4 respectively. Participants reported a median number of 5 (IQR 3-9) unique DRPs over all completed interviews. Unique patient-reported DRPs were most frequently categorized into (suspected) side effects (28%), medication management (e.g. medication administering or adherence) (26%), medication concerns (e.g. concerns regarding long-term side-effects or effectiveness) (19%) and medication effectiveness (17%).

Conclusion

Patients with rheumatic diseases experience various DRPs over time. These patients might benefit from continuous support during their patient journey.

References

[1]Huiskes, V. J. B., Burger, D. M., Van Den Ende, C. H. M. & Van Den Bemt, B. J. F. Effectiveness of medication review: A systematic review and meta-analysis of randomized controlled trials. BMC Fam. Pract.18, (2017).

[2]Kari, H., Kortejärvi, H., Airaksinen, M. & Laaksonen, R. Patient involvement is essential in identifying drug-related problems. Br. J. Clin. Pharmacol.84, 2048–2058 (2018).

[3]Kwint, H. F., Faber, A., Gussekloo, J. & Bouvy, M. L. The contribution of patient interviews to the identification of drug-related problems in home medication review. J. Clin. Pharm. Ther.37, 674–680 (2012).

Acknowledgements

The authors wish to thank the patients that participated in this study and the pharmacy technicians that conducted the structured interviews.

Disclosure of Interests

None declared

POS1526-HPR WHICH FACTORS INFLUENCE PATIENTS’ PREFERENCES FOR TELEHEALTH APPLICATIONS IN RHEUMATIC DISEASES? A QUALITATIVE STUDY

Background

Telehealth has the potential to improve patients’ health outcomes and patient empowerment by increasing access to care and medical information.1,2 As patients with rheumatic diseases are known to experience drug-related problems at various moments along their patient journey,3 this population can benefit from more continuous information about their medication and healthcare provider support to manage drug-related problems. To most effectively employ telehealth for this purpose, it is important that offered technologies match with patients’ needs and preferences.

Objectives

Identify factors influencing the preference of patients with rheumatic diseases regarding telehealth applications.

Methods

A qualitative descriptive study was performed in the Netherlands between May and June 2021. Using a semi-structured interview guide, patients with a rheumatic disease were interviewed face-to-face. First, patients were presented four telehealth applications (frequently asked questions page, digital human, and chatting and video calling with healthcare providers). Second, patients were asked to use each application to answer one medication-related question predefined by the research team. During the process of finding an answer to the question, patients were asked to think aloud and were questioned on which factors influenced their experience and preference for each application. Third, patients were given additional hypothetical questions after which they were asked to explain their preferred application for answering the question, to elicit additional factors influencing preference. Interviews were audio recorded, transcribed verbatim and analysed thematically.

Results

Fifteen patients (aged 19 – 73 years, 53% female) participated. Three domains influenced patients’ preference for telehealth applications. First, preference for telehealth applications was influenced by factors related to individual patients such as medication-related information needs, literacy, and skills with digital applications. Second, preference was influenced by factors related to the specific applications such as speed of answer, level of interaction, extent of privacy, the perceived usefulness of an application, and usability of the application. Third, preference was influenced by factors related to the context in which telehealth applications are offered, such as the support from healthcare providers in using telehealth applications, reliability of information source, and potential of telehealth to save time for healthcare providers.

Conclusion

Patients’ preference for telehealth applications is influenced by patient-related, application-related and context-related factors. To effectively support patients with rheumatic diseases, telehealth applications should match with these patients’ preferences. Furthermore, it is important to offer a variety of telehealth applications as preferences differ among patients and circumstances.

References

[1]Wootton, R. Twenty years of telemedicine in chronic disease management-an evidence synthesis. J. Telemed. Telecare18, 211–220 (2012).

[2]Barbosa, W., Zhou, K., Waddell, E., Myers, T. & Dorsey, E. R. Improving Access to Care: Telemedicine across Medical Domains. in Annual Review of Public Health vol. 42 463–481 (Annual Reviews, 2020).

[3]Haegens, L. L., Huiskes, V. J. B., Smale, E. M., Bekker, C. L. & van den Bemt, B. J. F. Drug-related problems experienced by patients with rheumatic diseases: A longitudinal observational study. Unpublished manuscript. (2021).

Disclosure of Interests

None declared

OP0118-HPR GAMING FOR ADHERENCE TO MEDICATION USING E-HEALTH IN RHEUMATOID ARTHRITIS (GAMER) STUDY – A RANDOMISED CLINICAL TRIAL

Background

Effectiveness of pharmacological therapy in rheumatoid arthritis (RA) is limited by inadequate medication adherence. Medication adherence can be influenced by implicit attitudes of personal medication needs and concerns about adverse consequences. We targeted these implicit attitudes using a serious puzzle game.

Objectives

To assess the effectiveness of a serious game compared to usual care to improve adherence to disease modifying anti-rheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA).

Methods

A multicentre randomised clinical trial was performed with a 3 month follow-up period.[1] Inclusion criteria were adulthood, RA diagnosis, use of DMARDs and possession of a smartphone/tablet. All participants received usual care. In addition, intervention participants were invited to play the serious puzzle game at will. The game was designed to influence players’ attitudes toward medication.[2] Collected data consisted of serious game play data, Compliance Questionnaire in Rheumatology (CQR), Beliefs about Medication Questionnaire (BMQ), Health Assessment Questionnaire (HAQ) and Rheumatoid Arthritis Disease Activity Index (RADAI).

Primary outcome was DMARD implementation adherence at three months assessed as the difference in proportion of non-adherent patients (<80% taking adherence) between intervention and control group using the discriminant function of the CQR using the Chi-squared test.

Two sample t-tests and Wilcoxon rank-sum test were performed to test for differences on secondary outcomes between study groups where appropriate.

Results

229 participants were randomised and 186 participants completed the study. Of the 85 intervention participants, 70 (82%) played the serious game for at least one hour. The serious game was played a median of 36 sessions with an average playtime of 25 minutes leading to a median overall playtime of 9.7 hours. A total of 59 (69%) intervention participants showed at least 40 days of gaming activity. Control group adherence (54%) and intervention group adherence (63%) based on the dichotomised CQR-score did not differ at three months (p = 0.26) (see Table 1). Neither was there a significant difference in CQR continuous score (p = 0.20), beliefs about medication differential score (p = 0.43) or clinical outcomes (HAQ: p = 0.97; RADAI: p = 0.90) (see Table 1).

Table 1.

Study outcomes at end-point (3 months)

Control group (n=101)Intervention group (n=85)p-valuePrimary outcomeAdherent no. (%)*55 (54)52 (63)0.26Secondary medication outcomesCQR continuous mean ± SD75 ± 1273 ± 110.20BMQ-Specific NCD score mean ± SD4.8 ± 4.25.3 ± 4.70.43Secondary clinical outcomesRADAI score median [IQR]2.5 [1.2 – 4.0]2.5 [1.5 – 4.2]0.90HAQ score median [IQR]0.8 [0.3 – 1.4]0.6 [0.3 – 1.4]0.97

Abbreviations: no. – number; SD – standard deviation; CQR – Compliance Questionnaire on Rheumatology; BMQ – Beliefs about Medication questionnaire; IQR – interquartile range

* Percentage of the total number of participants excluding missing data.

Conclusion

This multicentre randomised clinical trial showed that a serious puzzle game aimed at reinforcing a positive attitude towards DMARDs was frequently played during three months. Playing the game did not improve medication adherence nor influenced beliefs about medication or clinical outcomes in RA patients.

References

[1]https://www.trialregister.nl/trial/7217

[2]Pouls B, Bekker CL, van Dulmen S, Vriezekolk JE, van den Bemt BJF. A serious puzzle game to enhance adherence to anti-rheumatic drugs in rheumatoid arthritis patients: systematic development using Intervention Mapping. JMIR Serious Games. 06/11/2021:31570 (forthcoming/in press)

Disclosure of Interests

Bart Pouls: None declared, Charlotte Bekker: None declared, Johanna E. Vriezekolk: None declared, Sandra van Dulmen: None declared, Bart van den Bemt Speakers bureau: UCB, Pfizer, Sanofi-Aventis, Galapagos, Amgen en Eli Lilly

THU0447 HOME-MONITORING GOUT FLARES WITH A SMARTPHONE APP – RESULTS OF A FEASIBILITY STUDY

Background:

Gout flares are considered a key clinical and research outcome in gout. Early treatment of gout flares increases patient well-being and warrants timely notification of the treating clinician.

Objectives:

To test the feasibility of a smartphone app to home-monitor gout flares real-time for both patients with a suspicion of and established gout.

Methods:

Thirty patients were recruited during their visit at the outpatient rheumatology clinic. Inclusion criteria were age ≥ 18 years, smartphone possession, established gout (crystal proven) or a clinical suspicion of gout and at least one flare reported in the last three months.

A straight-forward query app was used to incorporate an adapted version of the 2017 four-criteria gout flare definition.[1] For 90 consecutive days the app asked patients to report their current pain score on an 11-points scale as screening question. Scoring pain below 4 terminated the query, otherwise the app posed the remaining criteria: does the patient experience warm and/or swollen joints and are symptoms regarded as a gout flare. Responses were transmitted in real-time to the dashboard and the clinician was alerted via email if predefined conditions were met. End of study evaluation consisted of the number of generated alerts, duration of (possible) flares and actions taken. Patient feasibility was assessed by measuring app attrition and using a questionnaire based on the Technology Acceptance Model. [2] All constructs were analysed using descriptive statistics.

Results:

All 30 recruited patients finished the trial. Three minor, resolvable technical issues were reported. Seventeen participants never missed a question. In total 110 responses (4.1%) were missed with three participants responsible for 66 missings. 90% of the participants rated app usability good to excellent and 70% would recommend the app to other patients.

Twelve out of thirty patients generated a total amount of 174 alerts where four patients with a suspicion of gout were responsible for 148 alerts (85%). These patients scored three out of four criteria as they had warm, swollen and painful joints but, after consultation with the clinician, their symptoms were not regarded as a gout flare.

The 174 alerts belonged to 23 (possible) flares with a median duration of 5 days [IQR 3,5 – 7,5]. Twenty-one pro-active telephone calls were made which resulted in four visits to the clinic within 48 hours. Clinical guidance over the phone consisted of checking in on patient’s symptoms, giving advice and ten medication adjustments.

Conclusion:

This prospective study shows feasibility of a smartphone app for home-monitoring gout flares for patients because of high usability scores and low attrition rates. The app has added value for gout care because it enables clinicians to act on flares as they occur. The next step is to further implement the app whilst perpetuating investigation into the added value for patients and clinical practice alike.

References:

[1]Gaffo AL, Dalbeth N, Saag KG, et al. Brief Report: Validation of a Definition of Flare in Patients With Established Gout. Arthritis Rheumatol. 2018;70(3):462-467.

[2]Davis Jr. FD. A Technology Acceptance Model for empirically testing new end-user information systems: theory and results. MIT PhD thesis. 1985

[3]Stoyanov SR, Hides L, Kavanagh DJ, Wilson H. Development and Validation of the User Version of the Mobile Application Rating Scale (uMARS). JMIR Mhealth Uhealth. 2016;4(2):e72.

Acknowledgements:

This study was funded by AbbVie and Menarini.

Disclosure of Interests: :

Bart Pouls: None declared, Charlotte Bekker: None declared, Bart van den Bemt Grant/research support from: UCB, Pfizer and Abbvie, Consultant of: Delivered consultancy work for UCB, Novartis and Pfizer, Speakers bureau: Pfizer, AbbVie, UCB, Biogen and Sandoz., Angelo Gaffo Grant/research support from: Received a research grant from AMGEN, Marcel Flendrie Grant/research support from: M. Flendrie has received grants from Menarini and Grunenthal.

, Consultant of: M. Flendrie has received consultancy fees from Menarini and Grunenthal.

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.

Eradication of Helicobacter pylori compared with long-term acid suppression in duodenal ulcer disease. A randomized trial with 2-year follow-up. The Danish Ulcer Study Group

BACKGROUND

Trials evaluating long-term management of duodenal ulcer disease have mainly been focused on recurrence of ulcers, disregarding effects on dyspeptic and reflux symptoms. Profound acid inhibition with a proton pump inhibitor is the gold standard therapy in acid-related diseases. We aimed to compare the symptomatic effects of eradication therapy with those of long-term omeprazole treatment in a design with periods both with and without acid inhibition.

METHODS

Patients with active duodenal ulcer were randomized either to omeprazole, 20 mg twice daily until healing, followed by omeprazole, 20 mg/ day for 1 year, or to eradication therapy (metronidazole, amoxicillin, and omeprazole for 2 weeks) followed by placebo for 1 year. All patients were followed up passively for an additional year. Clinical controls were performed every 2 months the 1st year (maintenance phase) and every 6 months during the passive follow-up phase. The study was multicentric and double-blind. The primary end-point was discontinuation of treatment, irrespective of reason.

RESULTS

Two hundred and seventy-six patients were randomized (139 in the eradication treatment group). In the maintenance phase there were no differences in the reporting of dyspeptic symptoms or in premature withdrawal. In the passive follow-up phase only five patients in the eradication therapy group discontinued owing to relapse of dyspeptic symptoms or ulcer, compared with 51 patients initially randomized to long-term omeprazole. There were no differences in reflux symptoms or in the development of reflux oesophagitis.

CONCLUSIONS

Eradication therapy and long-term omeprazole are equally effective in controlling dyspeptic symptoms and reflux in duodenal ulcer patients with healed ulcers. One-quarter of the duodenal ulcer patients who start eradication therapy continue to be symptomatic or fail therapy for other reasons over a 2-year period. Eradication therapy does not increase the risk of reflux in ulcer patients.

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.

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.

Sequence-specific oligonucleotide typing in Shona patients with rheumatoid arthritis and healthy controls from Zimbabwe

Seventy-two patients with rheumatoid arthritis (RA) and 82 controls have been typed with the XI Histocompatibility Workshop DRB1 and DQB1 sequence-specific oligonucleotide probes. The increase of DRB1*04 corresponds to an increase of the serologically defined DR4, previously found in a small group of Zimbabwean RA patients and we now show that this increase is due to the subtype DRB1*0405 in association with DQB1*0302. In addition there is a clearcut increase of DRB1*1001 equivalent to the serologically defined DR10. There was no increase amongst RA patients of DRB1*0102 which was the predominant DR1 sub-type amongst controls. In the course of our investigation, we observed a DRB1*04 variant which corresponds to DRB1*0412, newly defined in the XIth Histocompatibility Workshop.

Ranitidine and high-dose antacid in reflux oesophagitis. A randomized, placebo-controlled trial

The liquid antacid Novaluzid (10 ml seven times daily) was compared with ranitidine (150 mg twice daily) and with placebo in 57 patients with symptoms and endoscopic signs of oesophagitis and gastro-oesophageal reflux. A randomized three-period change-over design with the double-dummy technique was used. Each treatment period lasted 6 weeks. Only 37 patients (64.9%) completed the entire trial. In retrospect, five patients receiving placebo were withdrawn because of insufficient effect, six patients because of side effects while taking Novaluzid and two while taking ranitidine. The remaining seven dropouts/withdrawals were for reasons without evident relationship to the treatment given. Statistical analyses based both on the 37 completers and on the 43 patients who had at least two treatment periods showed that ranitidine and Novaluzid were superior to placebo with regard to pain score (p less than 0.005) but not with regard to regurgitation, dysphagia, histology, and appearance on endoscopy (p greater than 0.05). It was impossible to distinguish statistically between ranitidine and Novaluzid. In conclusion, ranitidine and high-dose antacids are of equal effectiveness in the short-term treatment of reflux oesophagitis, and both are superior to placebo with regard to symptomatic relief.

Comparison of ranitidine and high-dose antacid in the treatment of prepyloric or duodenal ulcer. A double-blind controlled trial

One hundred and nineteen patients with endoscopically confirmed prepyloric (n = 59) or duodenal (n = 60) ulcer were stratified for ulcer location before entering a randomized double-blind trial comparing ranitidine (150 mg twice daily) and a potent liquid antacid (Novaluzid; 10 ml seven times daily, with a neutralizing capacity of 600 mmol H+). Fifty-four patients with prepyloric (26 receiving ranitidine) and 53 patients with duodenal ulcer (28 receiving ranitidine) completed the trial in accordance with the protocol. The 4 and 6 weeks' healing rates for prepyloric ulcers were 54%, 68%, and 61%, versus 69%, 79%, and 74% for the ranitidine, the antacid, and whole groups, respectively. For duodenal ulcers these figures were 89%, 84%, and 87%, versus 100%, 96%, and 98% for the ranitidine, antacid, and whole groups, respectively. Differences in healing rates between treatments were statistically insignificant within strata for ulcer type, but healing rates for prepyloric ulcers were significantly lower than for duodenal ulcers (p less than 0.002). A significant early pain relief was found in all groups, and side effects, including diarrhoea, were rare. In conclusion, these two ulcer treatment modalities appear to be equally effective in the short term. In addition, the data emphasize the need for proper stratification of prepyloric and duodenal ulcers in clinical trials of ulcer healing.

Kinetics and in vivo distribution of 111-In-labelled autologous platelets in chronic hepatic disease: mechanisms of thrombocytopenia

The kinetics and distribution in vivo of autologous 111-In-labelled platelets were studied in 20 patients with chronic hepatic disease. The patients, 16 of whom were thrombocytopenic, exhibited a shortened platelet mean life time, a reduced platelet recovery and a normal platelet turnover, the latter 2 of which were positively correlated to the platelet count. Platelet in vivo recovery was negatively correlated to the spleen volume. In accordance with this, scintigraphic studies revealed that the spleen was the major organ of platelet sequestration and destruction, the role of the liver being almost negligible. Signs of platelet destruction in the bone marrow were also found. Our results indicate that splenic platelet pooling and accelerated platelet destruction, accompanied by inability of the bone marrow to compensate for the thrombocytopenia are the main causes of the thrombocytopenia accompanying chronic hepatic disease.

Dichotic listening and tactual mental rotation in females as a function of familial sinistrality and strength of handedness

In this study the effects of familial sinistrality and strength of handedness on dichotic listening and tactual mental rotation were investigated. Nonfamilial left-handers were inferior to familial left-handers, particularly in right-ear performance. The decrement in right-ear performance is interpreted as indicative of a pathologically functioning left hemisphere in nonfamilial left-handers. The direction of ear asymmetry tends to be more predictable in strong left-handers than in weak left-handers, with nonfamilial strong left-handers showing a significant left-ear superiority and familial strong left-handers a nonsignificant right-ear superiority. In the tactual mental rotation task, the results suggest a preference of left-handers for a verbal encoding strategy, especially in the right hemisphere. This preferential strategy is particularly manifest in familial weak left-handers and nonfamilial strong left-handers. The results are discussed in terms of their implications for underlying patterns of cerebral organization in the left-handers.

Effect of carbenoxolone on gastric prostaglandin E2 levels in patients with peptic ulcer disease following vagal and pentagastrin stimulation

The influence of oral carbenoxolone sodium (50 mg X 3 daily) on prostaglandin E2 release into gastric juice has been examined in nine peptic ulcer patients (duodenal ulcer, n = 6; prepyloric ulcer, n = 1; gastric ulcer, n = 2) during modified sham feeding and following bolus stimulation of acid secretion by pentagastrin (6 micrograms/kg). Carbenoxolone increased the overall mean of prostaglandin E2 concentrations in gastric juice following modified sham feeding by 32 +/- 9% (mean +/- SEM; P less than 0.02) and decreased the acidity slightly but significantly (P less than 0.05). A marked rise in prostaglandin E2 levels (46 +/- 11%; n = 5; P less than 0.02) was observed in for duodenal ulcer patients and the patient with a prepyloric ulcer responding to therapy (i.e., pain relief and ulcer healing within 4 weeks of treatment). A significant peak (P less than 0.05) related to modified sham feeding was observed only during medication, while a late gradual increase in prostaglandin E2 levels--not associated with vagal stimulation--occurred both in control and carbenoxolone experiments. No significant differences were observed following pentagastrin stimulation. The initial peak in prostaglandin E2 levels observed during medication favours the notion that the mechanism of drug action relies on inhibition of enzymatic degradation while the late increase in prostaglandin E2 levels may be explained by artificial prostaglandin formation during the aspiration procedure.

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.

Influence of beta blockade on gastric acid secretion and changes in gastric mucosal blood flow before and after parietal cell vagotomy in dogs and man

The aim of the present study was, in paired experiments in dogs, to examine the effect of beta-receptor blockade on gastric acid secretion and mucosal blood flow before and after parietal cell vagotomy (PCV). The secretory response to pentagastrin was reduced after vagotomy. beta-Adrenergic blockade had no effect on pentagastrin-stimulated gastric acid secretion before PCV, but after PCV beta blockade caused a modest increase in acid secretion, mediated mainly by the beta 2 receptors. A similar trend was seen in man. A marked increase in mucosal blood flow occurred 30 min after propranolol and was followed by a late decrease. One may conclude that a modest beta-adrenergic tone, which reduces secretion, becomes manifest after vagal denervation and that an increase in the ratio between mucosal blood flow and acid secretion was induced by the PCV. This increase cannot be explained as a beta-receptor-mediated effect.

Gastric acid response to sham feeding and pentagastrin before and after parietal cell vagotomy in patients with duodenal ulcer

The influence of sham feeding (PAOSh) preceding pentagastrin-stimulated gastric acid secretion (PAOPg) was investigated in 28 patients with duodenal ulcer (DU) before vagotomy and in 36 after parietal cell vagotomy (PCV). Sham feeding had little influence on PAOPg, and it is concluded that the two secretion tests may be combined. The ratio PAOSh/PAOPg was significantly reduced by PCV. Fourty-four patients with DU were studied for 1 year after PCV, and their PAOPg was measured preoperatively and their PAOPg and PAOSh postoperatively. Seven of the 44 patients had recurrent ulcer within 1 year. PAOPg had no predictive value pre- and post-operatively, but postoperative PAOSh and PAOSh/PAOPg were both significantly higher in patients with recurrent ulcer. It is concluded that PAOSh and PAOSh/PAOPg after PCV may assess completeness of vagotomy, but the relationship between PAOSh and risk of recurrent ulcer may be stronger than that between PAOSh/PAOPg and recurrence.