A Brain-Controlled and User-Centered Intelligent Wheelchair: A Feasibility Study

Recently, due to physical aging, diseases, accidents, and other factors, the population with lower limb disabilities has been increasing, and there is consequently a growing demand for wheelchair products. Modern product design tends to be more intelligent and multi-functional than in the past, with the popularization of intelligent concepts. This supports the design of a new, fully functional, intelligent wheelchair that can assist people with lower limb disabilities in their day-to-day life. Based on the UCD (user-centered design) concept, this study focused on the needs of people with lower limb disabilities. Accordingly, the demand for different functions of intelligent wheelchair products was studied through a questionnaire survey, interview survey, literature review, expert consultation, etc., and the function and appearance of the intelligent wheelchair were then defined. A brain-machine interface system was developed for controlling the motion of the intelligent wheelchair, catering to the needs of disabled individuals. Furthermore, ergonomics theory was used as a guide to determine the size of the intelligent wheelchair seat, and eventually, a new intelligent wheelchair with the features of climbing stairs, posture adjustment, seat elevation, easy interaction, etc., was developed. This paper provides a reference for the design upgrade of the subsequently developed intelligent wheelchair products.

T-Cells Subsets in Castleman Disease: Analysis of 28 Cases Including Unicentric, Multicentric and HHV8-Related Clinical Forms

Castleman disease (CD) is a rare lymphoproliferative disorder that includes various clinico-pathological subtypes. According to clinical course, CD is divided into unicentric CD (UCD) and multicentric CD (MCD). MCD is further distinguished based on the etiological driver in herpes virus-8-related MCD (that can occur in the setting of HIV); in MCD associated with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes); and idiopathic MCD (iMCD). The latter can also be divided in iMCD-TAFRO (thrombocytopenia, anasarca, fever, myelofibrosis, organomegaly) and iMCD not otherwise specified. To date, CD pathogenesis is still uncertain, but CD may represent the histological and clinical result of heterogeneous pathomechanisms. Transcriptome investigations in CD lymph nodes have documented the expression and up-regulation of different cytokines; furthermore, few recent studies have shown alterations of different T-cell subsets in CD patients, suggesting a possible role of the nodal microenvironment in CD development. On this basis, our study aimed to investigate the distribution of T-cell subsets in the clinico-pathological spectrum of CD. We evaluated the CD4/CD8 ratio and the number of T-regulatory (T-reg) FOXP3+ cells in 28 CD cases. In total, 32% of cases showed a decreased CD4/CD8 ratio due to increased CD8+ T-cells, including both UCD, iMCD, and HHV8+ MCD cases. The T-reg subset analysis revealed a statistically significant (p < 0.0001) lower mean number of FOXP3+ T-reg cells in CD cases when compared with non-specific reactive lymph nodes. We did not find statistically significant differences in T-reg numbers between the different CD subtypes. These findings may suggest that alterations in T-cell subpopulations that can lead to disruption of immune system control may contribute to the numerous changes in different cellular compartments that characterize CD.

Survival of infants and children born with severe microcephaly, Texas, 1999-2015

BACKGROUND

Severe microcephaly is a brain reduction defect where the delivery head circumference is <3rd percentile for gestational age and sex with subsequent lifelong morbidities. Our objective was to evaluate survival among 2,704 Texas infants with severe microcephaly delivered 1999-2015.

METHODS

Infants with severe microcephaly from the Texas Birth Defects Registry were linked to death certificates and the national death index. Survival estimates, hazard ratios (HR) and confidence intervals (CI) were calculated using the Kaplan-Meier method and Cox proportional hazards models stratified by presence versus absence of co-occurring defects.

RESULTS

We identified 496 deaths by age 4 years; most (42.9%) occurred in the neonatal period, and another 39.9% died by 1 year of age. Overall infant survival was 84.8%. Lowest infant survival subgroups included those with chromosomal/syndromic conditions (66.1%), very preterm deliveries (63.9%), or co-occurring critical congenital heart defects (44.0%). Among infants with severe microcephaly and a chromosomal/syndromic co-occurring defect, the risk of death was nearly three-fold higher among those with: proportionate microcephaly (i.e., small baby overall), relative to non-proportionate (HR = 2.84, 95% CI = 2.17-3.71); low-birthweight relative to normal (HR = 2.72, 95% CI = 1.92-3.85); critical congenital heart defects (CCHD) relative to no CCHD (HR = 2.90, 95% CI = 2.20-3.80). Trisomies were a leading underlying cause of death (27.5%).

CONCLUSIONS

Overall, infants with severe microcephaly had high 4-year survival rates which varied by the presence of co-occurring defects. Infants with co-occurring chromosomal/syndromic anomalies have a higher risk of death by age one than those without any co-occurring birth defects.

Human-Centered Design of Mobile Health Apps for Older Adults: Systematic Review and Narrative Synthesis

BACKGROUND

The world is aging. The number of older patients is on the rise, and along with it comes the burden of noncommunicable diseases, both clinical and economic. Attempts with mobile health (mHealth) have been made to remedy the situation with promising outcomes. Researchers have adopted human-centered design (HCD) in mHealth creation to ensure those promises become a reality.

OBJECTIVE

This systematic review aims to explore existing literature on relevant primary research and case studies to (1) illustrate how HCD can be used to create mHealth solutions for older adults and (2) summarize the overall process with recommendations specific to the older population.

METHODS

We conducted a systematic review to address the study objectives. IEEE Xplore, Medline via Ovid, PubMed, and Scopus were searched for HCD research of mHealth solutions for older adults. Two independent reviewers then included the papers if they (1) were written in English, (2) included participants equal to or older than 60 years old, (3) were primary research, and (4) reported about mHealth apps and their HCD developments from start to finish. The 2 reviewers continued to assess the included studies' qualities using the Mixed Methods Appraisal Tool (MMAT). A narrative synthesis was then carried out and completed.

RESULTS

Eight studies passed the eligibility criteria: 5 were mixed methods studies and 3 were case studies. Some studies were about the same mHealth projects with a total of 5 mHealth apps. The included studies differed in HCD goals, target groups, and details of their HCD methodologies. The HCD process was explored through narrative synthesis in 4 steps according to the International Standardization Organization (ISO) standard 9241-210: (1) understand and specify the context of use, (2) specify the user requirements, (3) produce design solutions to meet these requirements, and (4) evaluate the designs against requirements. The overall process and recommendations unique to older adults are summarized logically with structural order and time order based on the Minto pyramid principle and ISO 9241-210.

CONCLUSIONS

Findings show that HCD can be used to create mHealth solutions for older adults with positive outcomes. This review has also summarized practical HCD steps and additional suggestions based on existing literature in the subfield. However, evidence-based results are still limited because most included studies lacked details about their sampling methods and did not set objective and quantifiable goals, leading to failure to draw significant conclusions. More studies of HCD application on mHealth for older adults with measurable design goals and rigorous research strategy are warranted.

Enhancing System Acceptance through User-Centred Design: Integrating Patient Generated Wellness Data

Gestational diabetes mellitus (GDM) is a condition that appears during pregnancy and is expected to be a temporary one. While patients are encouraged to manage it themselves, research findings indicate that GDM may negatively affect the foetus; in addition, there is an increased risk of women with GDM subsequently developing Type 2 diabetes. To alleviate the risks, women with GDM are advised to maintain a record of their diet and blood glucose levels and to attend regular clinical reviews. Rather than using a paper diary, women with GDM can maintain a record of their blood glucose level readings and other relevant data using a wellness mobile application (app). However, such apps are developed for general use and may not meet the specific needs of clinical staff (physicians, dietitians, obstetricians and midwives) involved in managing GDM; for example, an app may record glucose readings but not the details of a meal taken before or after the glucose reading. Second, the apps do not permanently store the data generated by the patient and do not support the transfer of these data to a clinical system or information portal. The mobile health (mHealth) system designed and developed in this research allows one to integrate different types of user generated wellness data into a centralised database. A user-centered design (UCD) approach informed by the technology acceptance model (TAM) was adopted. This paper investigates and evaluates the effectiveness of the approach with regard to facilitating system acceptance and future adoption through an early focus on enhancing system usefulness and ease of use. The functional system requirements of the proposed system were refined through a series of interviews with the perspective of clinical users; ease-of-use and usability issues were resolved through 'think aloud' sessions with clinicians and GDM patients.

Designing a Solution to Manage Electronic Consent for Children

Electronic systems for managing consent do exist but are generally only able to record consent from the research subject directly. Consent for research is also challenging to integrate into many electronic patient record systems. The Born In Bradford study is a large, from birth cohort study in the North of England which requires consent to be recorded by the pregnant mother of a child who will be included in the study from birth. This creates a complex challenge for consent management that has previously been achieved through paper-based processes. As the study begins a new phase with the objective of inviting all new parents within the Bradford region to participate in the study the solution also needs to work with existing maternity systems. This paper considers the specific challenges of converting the often grey rules around consent of children into an electronic system that is transparent and supports the trust of both the family and the clinical and care teams recruiting research subjects into a large cohort study, and describes the user centred design and technical approach taken to resolve it.

A Persuasive mHealth Behavioral Change Intervention for Promoting Physical Activity in the Workplace: Feasibility Randomized Controlled Trial

Background

Employees in an office setting are more likely to remain physically inactive. Physical inactivity has become one of the major barriers to overcoming the risk factors for anxiety, depression, coronary heart disease, certain cancers, and type 2 diabetes. Currently, there is a gap in mobile health (mHealth) apps to promote physical activity (PA) for workers in the workplace. Studies on behavior change theories have concluded that health apps generally lack the use of theoretical constructs.

Objective

The objective of this study was to study the feasibility of a persuasive app aimed at encouraging PA among employees and to understand the motivational aspects behind the implementation of mHealth apps among office workers.

Methods

A 4-week study using a mixed methods (quantitative and qualitative) design was conducted with office-based employees in cities in 4 countries: Oulu, Finland; Carlow, Ireland; London, United Kingdom; and Dhaka, Bangladesh. Of the 220 invited participants (experimental group, n=115; control group, n=105), 84 participated (experimental group, n=56; control group, n=28), consisting of working-age volunteers working in an office setting. Participants used 2 different interventions: The experimental group used an mHealth app for PA motivation, and the control group used a paper diary. The purpose was to motivate employees to engage in healthier behavior regarding the promotion of PA in the workplace. A user-centered design process was followed to design, develop, and evaluate the mHealth app, incorporating self-determination theory (SDT) and using game elements. The paper diary had no specific theory-driven approach, design technique, nor game elements.

Results

Compliance with app usage remained relatively low, with 27 participants (experimental group, n=20; control group, n=7) completing the study. The results support the original hypothesis that the mHealth app would help increase PA (ie, promoting daily walking in the workplace) in comparison to a paper diary (P=.033). The mHealth app supported 2 of the basic SDT psychological needs, namely autonomy (P=.004) and competence (P=.014), but not the needs of relatedness (P=.535).

Conclusions

The SDT-based mHealth application motivated employees to increase their PA in the workplace. However, compliance with app usage remained low. Future research should further develop the app based on user feedback and test it in a larger sample.

Suggested guidelines for the diagnosis and management of urea cycle disorders: First revision

In 2012, we published guidelines summarizing and evaluating late 2011 evidence for diagnosis and therapy of urea cycle disorders (UCDs). With 1:35 000 estimated incidence, UCDs cause hyperammonemia of neonatal (~50%) or late onset that can lead to intellectual disability or death, even while effective therapies do exist. In the 7 years that have elapsed since the first guideline was published, abundant novel information has accumulated, experience on newborn screening for some UCDs has widened, a novel hyperammonemia-causing genetic disorder has been reported, glycerol phenylbutyrate has been introduced as a treatment, and novel promising therapeutic avenues (including gene therapy) have been opened. Several factors including the impact of the first edition of these guidelines (frequently read and quoted) may have increased awareness among health professionals and patient families. However, under-recognition and delayed diagnosis of UCDs still appear widespread. It was therefore necessary to revise the original guidelines to ensure an up-to-date frame of reference for professionals and patients as well as for awareness campaigns. This was accomplished by keeping the original spirit of providing a trans-European consensus based on robust evidence (scored with GRADE methodology), involving professionals on UCDs from nine countries in preparing this consensus. We believe this revised guideline, which has been reviewed by several societies that are involved in the management of UCDs, will have a positive impact on the outcomes of patients by establishing common standards, and spreading and harmonizing good practices. It may also promote the identification of knowledge voids to be filled by future research.

Urea cycle disorders in India: clinical course, biochemical and genetic investigations, and prenatal testing

Background

Urea cycle disorders (UCDs) are inherited metabolic disorders that present with hyperammonemia, and cause significant mortality and morbidity in infants and children. These disorders are not well reported in the Indian population, due to lack of a thorough study of the clinical and molecular profile.

Results

We present data from two major metabolic centres in India, including 123 cases of various UCDs. The majority of them (72/123, 58%) presented in the neonatal period (before 30 days of age) with 88% on or before day 7 of life (classical presentation), and had a high mortality (64/72, 88%). Citrullinemia type 1 was the most common UCD, observed in 61/123 patients. Ornithine transcarbamylase (OTC) deficiency was the next most common, seen in 24 cases. Argininosuccinic aciduria was diagnosed in 20 cases. Deficiencies of arginase, N-acetylglutamate synthase, carbamoyl phosphate synthetase, citrin, and lysinuric protein intolerance were also observed.

Molecular genetic analysis revealed two common ASS1 mutations: c.470G > A (p.Arg157His) and c.1168G > A (p.Gly390Arg) (36 of 55 tested patients). In addition, few recurrent point mutations in ASL gene, and a deletion of the whole OTC gene were also noted. A total of 24 novel mutations were observed in the various genes studied. We observed a poor clinical outcome with an overall all time mortality of 63% (70/110 cases with a known follow-up), and disability in 70% (28/40) among the survivors. Prenatal diagnosis was performed in 30 pregnancies in 25 families, including one pre-implantation genetic diagnosis.

Conclusions

We report the occurrence of UCDs in India and the spectrum that may be different from the rest of the world. Citrullinemia type 1 was the most common UCD observed in the cohort. Increasing awareness amongst clinicians will improve outcomes through early diagnosis and timely treatment. Genetic diagnosis in the proband will enable prenatal/pre-implantation diagnosis in subsequent pregnancies.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0908-1) contains supplementary material, which is available to authorized users.

Late onset hyperornithinemia-hyperammonemia-homocitrullinuria syndrome - how web searching by the family solved unexplained unconsciousness: a case report

Background

Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome, a rare inherited urea cycle disorder, can remain undiagnosed for decades and suddenly turn into an acute life-threatening state. Adult presentation of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome has rarely been described, but is potentially underdiagnosed in the emergency room. In the case of acute hyperammonemia, prompt diagnosis is essential to minimize the risk of brain damage and death.

Case presentation

We present the diagnostics, clinical course, and treatment of a 48-year-old Caucasian man presenting with unexplained unconsciousness in the emergency room. A web search by a family member led to the suspicion of urea cycle disorder. Subsequent analysis of plasma ammonia and amino acids in plasma and urine demonstrated a pattern typical for hyperornithinemia-hyperammonemia-homocitrullinuria syndrome. The diagnosis was confirmed by genetic analysis which revealed two heterozygous mutations in the SLC25A15 gene. The cause of the hyperammonemia crisis was acute upper gastrointestinal hemorrhage, leading to protein overload and subsequent cerebral edema. Continuous renal replacement therapy, scavenger treatment, and tightly controlled nutrition were useful in preventing hyperammonemia and recurrence of cerebral edema.

Conclusions

The case emphasizes the importance of taking rare metabolic genetic disorders into consideration in patients with prolonged unexplained unconsciousness.

In vivo monitoring of urea cycle activity with (13)C-acetate as a tracer of ureagenesis

BACKGROUND

The hepatic urea cycle is the main metabolic pathway for detoxification of ammonia. Inborn errors of urea cycle function present with severe hyperammonemia and a high case fatality rate. Long-term prognosis depends on the residual activity of the defective enzyme. A reliable method to estimate urea cycle activity in-vivo does not exist yet. The aim of this study was to evaluate a practical method to quantify (13)C-urea production as a marker for urea cycle function in healthy subjects, patients with confirmed urea cycle defect (UCD) and asymptomatic carriers of UCD mutations.

METHODS

(13)C-labeled sodium acetate was applied orally in a single dose to 47 subjects (10 healthy subjects, 28 symptomatic patients, 9 asymptomatic carriers).

RESULTS

The oral (13)C-ureagenesis assay is a safe method. While healthy subjects and asymptomatic carriers did not differ with regards to kinetic variables for urea cycle flux, symptomatic patients had lower (13)C-plasma urea levels. Although the (13)C-ureagenesis assay revealed no significant differences between individual urea cycle enzyme defects, it reflected the heterogeneity between different clinical subgroups, including male neonatal onset ornithine carbamoyltransferase deficiency. Applying the (13)C-urea area under the curve can differentiate between severe from more mildly affected neonates. Late onset patients differ significantly from neonates, carriers and healthy subjects.

CONCLUSION

This study evaluated the oral (13)C-ureagenesis assay as a sensitive in-vivo measure for ureagenesis capacity. The assay has the potential to become a reliable tool to differentiate UCD patient subgroups, follow changes in ureagenesis capacity and could be helpful in monitoring novel therapies of UCD.

Infectious precipitants of acute hyperammonemia are associated with indicators of increased morbidity in patients with urea cycle disorders

OBJECTIVE

To prospectively characterize acute hyperammonemic episodes in patients with urea cycle disorders (UCDs) in terms of precipitating factors, treatments, and use of medical resources.

STUDY DESIGN

This was a prospective, longitudinal observational study of hyperammonemic episodes in patients with UCD enrolled in the National Institutes of Health-sponsored Urea Cycle Disorders Consortium Longitudinal Study. An acute hyperammonemic event was defined as plasma ammonia level >100 μmol/L. Physician-reported data regarding the precipitating event and laboratory and clinical variables were recorded in a central database.

RESULTS

In our study population, 128 patients with UCD experienced a total of 413 hyperammonemia events. Most patients experienced between 1 and 3 (65%) or between 4 and 6 (23%) hyperammonemia events since study inception, averaging fewer than 1 event/year. The most common identifiable precipitant was infection (33%), 24% of which were upper/lower respiratory tract infections. Indicators of increased morbidity were seen with infection, including increased hospitalization rates (P = .02), longer hospital stays (+2.0 days; P = .003), and increased use of intravenous ammonia scavengers (+45%-52%; P = .003-.03).

CONCLUSION

Infection is the most common precipitant of acute hyperammonemia in patients with UCD and is associated with indicators of increased morbidity (ie, hospitalization rate, length of stay, and use of intravenous ammonia scavengers). These findings suggest that the catabolic and immune effects of infection may be a target for clinical intervention in inborn errors of metabolism.

Elevated phenylacetic acid levels do not correlate with adverse events in patients with urea cycle disorders or hepatic encephalopathy and can be predicted based on the plasma PAA to PAGN ratio

BACKGROUND

Phenylacetic acid (PAA) is the active moiety in sodium phenylbutyrate (NaPBA) and glycerol phenylbutyrate (GPB, HPN-100). Both are approved for treatment of urea cycle disorders (UCDs) - rare genetic disorders characterized by hyperammonemia. PAA is conjugated with glutamine in the liver to form phenylacetyleglutamine (PAGN), which is excreted in urine. PAA plasma levels ≥ 500 μg/dL have been reported to be associated with reversible neurological adverse events (AEs) in cancer patients receiving PAA intravenously. Therefore, we have investigated the relationship between PAA levels and neurological AEs in patients treated with these PAA pro-drugs as well as approaches to identifying patients most likely to experience high PAA levels.

METHODS

The relationship between nervous system AEs, PAA levels and the ratio of plasma PAA to PAGN were examined in 4683 blood samples taken serially from: [1] healthy adults [2], UCD patients of ≥ 2 months of age, and [3] patients with cirrhosis and hepatic encephalopathy (HE). The plasma ratio of PAA to PAGN was analyzed with respect to its utility in identifying patients at risk of high PAA values.

RESULTS

Only 0.2% (11) of 4683 samples exceeded 500 μg/ml. There was no relationship between neurological AEs and PAA levels in UCD or HE patients, but transient AEs including headache and nausea that correlated with PAA levels were observed in healthy adults. Irrespective of population, a curvilinear relationship was observed between PAA levels and the plasma PAA:PAGN ratio, and a ratio>2.5 (both in μg/mL) in a random blood draw identified patients at risk for PAA levels>500 μg/ml.

CONCLUSIONS

The presence of a relationship between PAA levels and reversible AEs in healthy adults but not in UCD or HE patients may reflect intrinsic differences among the populations and/or metabolic adaptation with continued dosing. The plasma PAA:PAGN ratio is a functional measure of the rate of PAA metabolism and represents a useful dosing biomarker.

Improving surveillance for hyperammonemia in the newborn

OBJECTIVE

Prompt ascertainment is crucial for the management of hyperammonemic infants. Because these patients are rare and recognition of hyperammonemia is often delayed, we designed and implemented an electronic medical record (EMR)-based tool to assist physicians in the detection of hyperammonemia.

METHODS

We retrospectively evaluated the hospitalizations of prior hyperammonemic infants to identify codable elements that could trigger an EMR-based warning. An alert was designed and implemented and its utilization was prospectively analyzed.

RESULTS

Blood gas studies were obtained universally and early in the retrospectively evaluated infants (x¯=26h before ammonia level). Prompting physicians to evaluate ammonia after ordering blood gas studies would have accelerated the initial ammonia order in 89% of retrospective cases. The alert has activated 184 times over the first six months of operation leading to 63 laboratory evaluations and detection of one hyperammonemic infant.

CONCLUSION

Implementation of an EMR-based warning system can improve surveillance for hyperammonemia in a susceptible population.

Feasibility of adjunct therapeutic hypothermia treatment for hyperammonemia and encephalopathy due to urea cycle disorders and organic acidemias

BACKGROUND

Children with urea cycle disorders (UCDs) or organic acidemias (OAs) and acute hyperammonemia and encephalopathy are at great risk for neurological injury, developmental delay, intellectual disability, and death. Nutritional support, intravenous alternative pathway therapy, and dialysis are used to treat severe hyperammonemia associated with UCDs and nutritional support and dialysis are used to treat severe hyperammonemia in OAs. Brain protective treatment while therapy is initiated may improve neurological and cognitive function for the lifetime of the child. Animal experiments and small clinical trials in hepatic encephalopathy caused by acute liver failure suggest that therapeutic hypothermia provides neuroprotection in hyperammonemia associated encephalopathy. We report results of an ongoing pilot study that assesses if whole body cooling during rescue treatment of neonates with acute hyperammonemia and encephalopathy is feasible and can be conducted safely.

METHODS

Adjunct whole body therapeutic hypothermia was conducted in addition to standard treatment in acutely encephalopathic, hyperammonemic neonates with UCDs and OAs requiring dialysis. Therapeutic hypothermia was initiated using cooling blankets as preparations for dialysis were underway. Similar to standard therapeutic hypothermia treatment for neonatal hypoxic ischemic encephalopathy, patients were maintained at 33.5°C±1°C for 72h, they were then slowly rewarmed by 0.5°C every 3h over 18h. In addition data of age-matched historic controls were collected for comparison.

RESULTS

Seven patients were cooled using the pilot study protocol and data of seven historic controls were reviewed. All seven patients survived the initial rescue and cooling treatment, 6 patients were discharged home 2-4weeks after hospitalization, five of them feeding orally. The main complication observed in a majority of patients was hypotension.

CONCLUSION

Adjunct therapeutic hypothermia for neonates with UCDs and OAs receiving standard treatment was feasible and could be conducted safely in pediatric and neonatal intensive care units experienced in the application of therapeutic hypothermia in critically ill neonates. However, including adjunct therapeutic hypothermia in the already involved treatment regimen of critically ill patients with hyperammonemia and encephalopathy adds to the complexity of care and should not be done unless it is proven efficacious in a randomized clinical trial.