Comparing the performance of pediatric weight estimation methods.

BACKGROUND: Weight estimation is essential in the care of ill children when a weight cannot be obtained. This is particularly important for children with medical complexity, who are at higher risk for adverse drug events. Our objective was to compare the accuracy of different methods of weight estimation in children and stratify by the presence of medical complexity. METHODS: We performed a retrospective cross-sectional study of children (<18 years) seen in the emergency department (ED) or ambulatory clinic from January 1, 2013 to December 31, 2022 at a tertiary academic pediatric center. We compared the performance of nine age-based formulae and two length-based methods using metrics of mean average error (MAE), root mean square error (RMSE), and agreement within 10% and 20% of measured weight. We additionally evaluated the approaches stratified by body mass index (BMI) and the presence of medical complexity. RESULTS: Of 361,755 children (median age 8.2 years, IQR 2.5-14.2 years; 51.5% male), 59,283 (16.4%) were seen in the ED. Length was measured or available in 21,330 (36.0%) patients in the ED and 293,410 (97%) patients in clinics. The Broselow tape outperformed all methods, with 50.7% estimates within 10% of measured weight, 80.0% estimates within 20% of measured weight, the lowest MAE (2.5 kg), and lowest RMSE (4.5 kg). The Antevy formula was the most accurate age-based formula, with 49.2% estimates within 10% of measured weight, 80.1% estimates within 20% of measured weight, MAE of 2.8 kg, and RMSE of 4.7 kg. Estimates became less accurate as BMI and estimated weight increased for all methods. Among children with medical complexity (14.1%), the Broselow tape consistently outperformed age-based formulae, with 47.7% estimates within 10% of measured weight, 77.1% estimates within 20% of measured weight, MAE of 2.6 kg, and RMSE of 5.4 kg. The Antevy formula remained the most accurate age-based method among children with medical complexity. CONCLUSION: The Broselow tape predicted weight most accurately in this large sample of children, including among those with medical complexity. The Antevy formula is the most accurate age-based method for pediatric weight estimation.

Risk factors and mortality of SARS-CoV-2 reinfection during the Omicron era in Taiwan: A nationwide population-based cohort study.

BACKGROUND: Prior to 2022, Taiwan had effectively contained the domestic COVID-19 epidemic. However, during 2022, the country encountered multiple large outbreaks of COVID-19, with patients experiencing their first or second infection (reinfection) were both predominantly caused by the Omicron variant. Data are lacking on the risk factors and mortality of COVID-19 reinfection in Omicron era. METHODS: In this retrospective population-based cohort study, we recruited COVID-19 patients with their first episode confirmed between April 1, 2022 and June 11, 2022. A reinfection patient was defined as an individual who infected again by SARS-CoV-2 with an interval of more than 90 days. Demographic characteristics, severity of underlying diseases, and vaccination status were adjusted to identify risk factors for reinfection and to further evaluate the hazard of all-cause mortality within 30 days between reinfection and non-reinfection patients. RESULTS: There were 28,588 reinfection patients matched with 142,940 non-reinfection patients included in this study. We found that being female, younger in age, having more severe underlying diseases, and not being fully vaccinated against COVID-19 were risk factors for reinfection. After adjusting for confounding factors, reinfection patients were at a significantly higher risk of all-cause mortality within 30 days (aHR = 4.29, 95% CI: 3.00-6.12, p < 0.001) comparing with non-reinfection patients. CONCLUSION: During the SARS-CoV-2 Omicron era, reinfection patients were observed to have an increased risk of all-cause mortality. To reduce the disease burden and minimize the risk of reinfection, it is crucial for vulnerable patients to receive full vaccination and adhere to recommended precautions.

Impact of emergency department-based intensive care unit on outcomes of decompensating boarding emergency department patients.

Objectives: Emergency department (ED) boarding, or remaining in the ED after admission before transfer to an inpatient bed, is prevalent. Boarding patients may decompensate before inpatient transfer, necessitating escalation to the intensive care unit (ICU). We evaluated the impact of an ED-ICU on decompensating boarding ED patients. Methods: This is a retrospective single-center observational study. We identified decompensated boarding ED patients necessitating critical care before departure from the ED from October 2012 to December 2021. An automated query and manual chart review extracted data. Three cohorts were defined: pre-ED-ICU implementation (Group 1), post-ED-ICU implementation with ED-ICU care (Group 2), and post-ED-ICU implementation with inpatient ICU admission without ED-ICU care (Group 3). Primary outcome was ICU length of stay (LOS). Secondary outcomes included hospital LOS, in-hospital mortality, and ICU admissions with ICU LOS <24 hours. Between-groups comparisons used multiple regression analysis for continuous variables, χ2 tests and multivariable logistic regression analysis for binary variables, and follow-up contrasts for statistically significant omnibus tests. Results: A total of 1123 visits met inclusion criteria: 225 in Group 1, 780 in Group 2, and 118 in Group 3. Mean ICU LOS was shorter for Group 2 than Group 1 or 3 (47.4 vs 92.3 vs 103.9 hours, P < 0.001). Mean hospital LOS was shorter for Group 2 than Group 1 or 3 (185.1 vs 246.8 vs 257.3 hours, P < 0.01). In-hospital mortality was similar between groups. The proportion of ICU LOS <24 hours was lower for Group 2 than Group 1 or 3 (16.5 vs 27.1 vs 32.2%, P < 0.01). Conclusion: For decompensating boarding ED patients, ED-ICU care was associated with decreased ICU and hospital LOS, similar mortality, and fewer short-stay ICU admissions, suggesting ED-ICU care is associated with downstream resource preservation.

Epidemiological characteristics of the three waves of COVID-19 epidemic in Taiwan during April 2022 to March 2023.

BACKGROUND: Taiwan experienced a relatively low incidence of COVID-19 before 2022. However, from April 2022 to March 2023, the country was struck by a nationwide outbreak that occurred in three waves. Despite the considerable magnitude of the epidemic, the epidemiological characteristics of this outbreak have yet to be clearly understood. METHODS: This was a nationwide, population-based, retrospective cohort study. We recruited patients who had been confirmed as domestically-acquired COVID-19 patients from April 17, 2022, to March 19, 2023. The three epidemic waves were analyzed in terms of numbers of cases, cumulative incidence, numbers of COVID-19-related deaths, mortality, gender, age, residence, SARS-CoV-2 variant sub-lineages, and reinfection status. RESULTS: The numbers of COVID-19 patients (cumulative incidence per million population) were 4,819,625 (207,165.3) in the first wave, 3,587,558 (154,206.5) in the second wave, and 1,746,698 (75,079.5) in the third wave, showing a progressive decline. The numbers of COVID-19-related deaths and mortalities also decreased throughout the three waves. The coverage of vaccination was observed to increase over time. CONCLUSION: During the three waves of COVID-19 epidemic, the numbers of cases and deaths gradually declined, while the vaccine coverage increased. It may be appropriate to consider easing restrictions and returning to normality. However, continued monitoring of the epidemiological situation and tracking the emergence of new variants are crucial to prevent the possibility of another epidemic.

The secular trend of enterovirus A71 after the implementation of preventive measures in Taiwan.

BACKGROUND: Enterovirus A71 (EV A71) is one of the most important enteroviruses related to morbidity and mortality in children worldwide. This study aimed to analyse the secular trend of EV A71 in Taiwan from 1998 to 2020 and to evaluate the effectiveness of infection control measures. METHODS: We collected the epidemiological data of EV A71 from disease surveillance systems in Taiwan. We analysed the association between the secular trend of EV A71 and preventive measures such as hand washing, case isolation, and suspension of classes. RESULTS: The incidence of enterovirus infections with severe complications (EVSC) decreased from 16.25 per 100,000 children under six in 1998 to less than 9.73 per 100,000 children under six after 2012 (P = 0.0022). The mortality rate also decreased significantly, from 3.52 per 100,000 children under six in 1998 to 0 per 100,000 children under six in 2020 (P < 0.0001). The numbers of EVSC and fatalities were significantly higher in the years when EV A71 accounted for more than 10% of the annual predominant serotypes (p < 0.05). After the implementation of many non-pharmaceutical interventions in 2012, the incidence of EVSC and mortality rate decreased significantly (p < 0.001). CONCLUSIONS: After implementing active enterovirus surveillance and preventive measures, we found that the incidence of EVSC and fatalities due to EV A71 in Taiwan decreased significantly from 1998 to 2020. Continuous surveillance and strengthened infection control policies are still needed in the future.

Initiation of a Lung Protective Ventilation Strategy in the Emergency Department: Does an Emergency Department-Based ICU Make a Difference?

BACKGROUND: Lung protective ventilation (LPV) is a key component in the management of acute respiratory distress syndrome and other acute respiratory pathology. Initiation of LPV in the emergency department (ED) is associated with improved patient-centered and system outcomes, but adherence to LPV among ED patients is low. The impact of an ED-based ICU (ED-ICU) on LPV adherence is not known. METHODS: This single-center, retrospective, cohort study analyzed rates of adherence to a multifaceted LPV strategy pre- and post-implementation of an ED-ICU. LPV strategy components included low tidal volume ventilation, avoidance of severe hyperoxia and high plateau pressures, and positive end-expiratory pressure settings in alignment with best-evidence recommendations. The primary outcome was adherence to the LPV strategy at time of ED departure. RESULTS AND CONCLUSIONS: A total of 561 ED visits were included in the analysis, of which 60.0% received some portion of their emergency care in the ED-ICU. Adherence to the LPV strategy was statistically significantly higher in the ED-ICU cohort compared with the pre-ED-ICU cohort (65.8% vs 41.4%; p < 0.001) and non-ED-ICU cohort (65.8% vs 43.1%; p < 0.001). Among the ED-ICU cohort, 92.8% of patients received low tidal volume ventilation. Care in the ED-ICU was also associated with shorter ICU and hospital length of stay. These findings suggest improved patient and resource utilization outcomes for mechanically ventilated ED patients receiving care in an ED-ICU.

Developing an electronic health record-derived health equity dashboard to improve learner access to data and metrics.

OBJECTIVES: It is essential to engage learners in efforts aimed at dismantling racism and other contributors to health care disparities. Barriers to their involvement include limited access to data. The objective of our study was to create a data dashboard using an existing quality improvement (QI) infrastructure and provide resident access to data to facilitate exploratory analysis on disparities in emergency department (ED) patient care. METHODS: Focusing on patient populations that have previously been shown in the literature to suffer significant disparities in the ED, we extracted outcomes across a variety of metrics already collected as part of routine ED operations. Using data visualization software, we developed an interactive dashboard for visual exploratory analyses. RESULTS: We designed a dashboard for our resident learners with views that are flexible and allow user selected filters to view clinical outcomes by patient age, treatment area, and chief complaint. Learners were also allowed to select grouping and outcomes of interest to investigate questions and form new hypotheses of their choosing. Available dashboard views included summary counts view to assess ED visits over time by selectable group, a rooming and triage acuity view, time-to-event survival curve view, histogram and box plot views for continuous variables, a view to assess outcome variables by time of day of ED arrival, customizable contingency table views, and correspondence analysis. CONCLUSIONS: Utilizing an existing QI infrastructure, we developed a dashboard that provides a new perspective into commonly collected ED operations data to allow for the exploration of disparities in ED care that is accessible to learners. Future directions include using these data to refine hypotheses on ED disparities, understand root causes, develop interventions, and measure their impact.

Taiwan's COVID-19 response: Timely case detection and quarantine, January to June 2020.

The coronavirus disease 2019 (COVID-19) pandemic has become severe threats to economic, societal, and healthcare systems. To analyze the epidemiological characteristics of the COVID-19 outbreak in Taiwan and evaluate the key interventions, we conducted a retrospective cohort study during January 17-June 30, 2020. As of June 30, the COVID-19 outbreak, including 447 laboratory-confirmed cases, was eliminated by mixed approaches: border control, enhanced surveillance, case detection with contact tracing, quarantine, and population-based interventions like face mask use. The improvement of median time from disease onset to notification (5 days [range -3 to 27] before March 1 to 1 day [range -8 to 22] after March 1) suggested the timeliness and comprehensiveness of surveillance and contact tracing. Travel restrictions with quarantine, resulting in fewer clusters, were also complementary to minimize disease spread. Under combined interventions, Taiwan successfully contained the COVID-19 spread within the country and minimized its impact on the society.

Applying Machine Learning Models with An Ensemble Approach for Accurate Real-Time Influenza Forecasting in Taiwan: Development and Validation Study.

BACKGROUND: Changeful seasonal influenza activity in subtropical areas such as Taiwan causes problems in epidemic preparedness. The Taiwan Centers for Disease Control has maintained real-time national influenza surveillance systems since 2004. Except for timely monitoring, epidemic forecasting using the national influenza surveillance data can provide pivotal information for public health response. OBJECTIVE: We aimed to develop predictive models using machine learning to provide real-time influenza-like illness forecasts. METHODS: Using surveillance data of influenza-like illness visits from emergency departments (from the Real-Time Outbreak and Disease Surveillance System), outpatient departments (from the National Health Insurance database), and the records of patients with severe influenza with complications (from the National Notifiable Disease Surveillance System), we developed 4 machine learning models (autoregressive integrated moving average, random forest, support vector regression, and extreme gradient boosting) to produce weekly influenza-like illness predictions for a given week and 3 subsequent weeks. We established a framework of the machine learning models and used an ensemble approach called stacking to integrate these predictions. We trained the models using historical data from 2008-2014. We evaluated their predictive ability during 2015-2017 for each of the 4-week time periods using Pearson correlation, mean absolute percentage error (MAPE), and hit rate of trend prediction. A dashboard website was built to visualize the forecasts, and the results of real-world implementation of this forecasting framework in 2018 were evaluated using the same metrics. RESULTS: All models could accurately predict the timing and magnitudes of the seasonal peaks in the then-current week (nowcast) (ρ=0.802-0.965; MAPE: 5.2%-9.2%; hit rate: 0.577-0.756), 1-week (ρ=0.803-0.918; MAPE: 8.3%-11.8%; hit rate: 0.643-0.747), 2-week (ρ=0.783-0.867; MAPE: 10.1%-15.3%; hit rate: 0.669-0.734), and 3-week forecasts (ρ=0.676-0.801; MAPE: 12.0%-18.9%; hit rate: 0.643-0.786), especially the ensemble model. In real-world implementation in 2018, the forecasting performance was still accurate in nowcasts (ρ=0.875-0.969; MAPE: 5.3%-8.0%; hit rate: 0.582-0.782) and remained satisfactory in 3-week forecasts (ρ=0.721-0.908; MAPE: 7.6%-13.5%; hit rate: 0.596-0.904). CONCLUSIONS: This machine learning and ensemble approach can make accurate, real-time influenza-like illness forecasts for a 4-week period, and thus, facilitate decision making.

Real-Time Surveillance of Infectious Diseases: Taiwan's Experience.

Integration of multiple surveillance systems advances early warning and supports better decision making during infectious disease events. Taiwan has a comprehensive network of laboratory, epidemiologic, and early warning surveillance systems with nationwide representation. Hospitals and clinical laboratories have deployed automatic reporting mechanisms since 2014 and have effectively improved timeliness of infectious disease and laboratory data reporting. In June 2016, the capacity of real-time surveillance in Taiwan was externally assessed and was found to have a demonstrated and sustainable capability. We describe Taiwan's disease surveillance system and use surveillance efforts for influenza and Zika virus as examples of surveillance capability. Timely and integrated influenza information showed a higher level and extended pattern of influenza activity during the 2015-16 season, which ensured prompt information dissemination and the coordination of response operations. Taiwan also has well-developed disease detection systems and was the first country to report imported cases of Zika virus from Miami Beach and Singapore. This illustrates a high level of awareness and willingness among health workers to report emerging infectious diseases, and highlights the robust and sensitive nature of Taiwan's surveillance system. These 2 examples demonstrate the flexibility of the surveillance systems in Taiwan to adapt to emerging infectious diseases and major communicable diseases. Through participation in the GHSA, Taiwan can more actively collaborate with national counterparts and use its expertise to strengthen global and regional surveillance capacity in the Asia Pacific and in Southeast Asia, in order to advance a world safe and secure from infectious disease.

Low estimated glomerular filtration rate is associated with poor outcomes in patients who suffered a large artery atherosclerosis stroke.

OBJECTIVES: The relationship between low estimated glomerular filtration rate (eGFR) and the outcome of ischemic stroke remains controversial, despite the close association between kidney dysfunction and atherosclerosis. METHODS: This study conducted subgroup analysis using data from the prospective Taiwan Stroke Registry to investigate the relationship between eGFR at the time of admission and 6-month functional outcomes in patients with the large artery atherosclerotic (LAA) subtype of acute ischemic stroke. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and outcomes were defined as modified Rankin Scale and mortality status at 6 months post stroke. RESULTS: Of the 8052 patients with the LAA subtype of acute ischemic stroke in this study, 3312 (41.1%) had eGFR <60 mL/min/1.73 m(2). The adjusted odds ratios of worse functional outcomes following a stroke were 1.10 (95% confidence interval [CI], 0.95-1.28), 1.60 (95% CI, 1.22-2.11) and 1.60 (95% CI, 1.10-2.33) in patients with eGFR 30-59, 15-29, and <15 as compared with those with eGFR 60-119 mL/min/1.73 m(2), respectively. Increased risk of mortality was closely and independently related to high NIHSS scores and low eGFR levels. Stroke severity and eGFR were also synergistically related to 6-month mortality, with an adjusted hazard ratio of 21.19 (95% CI, 9.69-46.35) in patients with NIHSS >15 and eGFR <15 mL/min/1.73 m(2), compared with those with NIHSS 0-5 and eGFR 60-119 mL/min/1.73 m(2). CONCLUSIONS: Low eGFR was significantly and independently associated with 6-month functional outcomes and mortality in patients with the LAA subtype of acute ischemic stroke. The deleterious relationship between low eGFR levels and mortality following stroke was exacerbated by its synergistic association with stroke severity.

Evaluation on the Pharmacological Effect of Traditional Chinese Medicine SiJunZiTang on Stress-Induced Peptic Ulcers.

Purpose. To explore the effects of SiJunZiTang (SJZT) on central neurotransmitters and the inhibition of HCl hypersecretion, along with the role of the vagus nerve. From this, the effects of SJZT and its constituent ingredients on inhibiting stress-induced peptic ulcers will be determined. Methods. Methods used to determine SJZT's effectiveness included (1) measuring the antipeptic ulcer effects of varying combinations of the constituents of SJZT; (2) evaluations of monoamine (MA) level in the brain; and (3) measuring the effects of longer-term SJZT treatment. Results. Comparing the control and experimental groups where the rats' vagus nerves were not cut after taking SJZT orally (500 mg/kg and 1000 mg/kg), the volume of enterogastric juice, free HCl and total acidity all reduce dose-dependently. The group administered SJZT at 1000 mg/kg showed significant reductions (P < 0.05). For the experimental groups where the vagus nerves were cut, a comparison with the control group suggests that the group receiving SJZT (500 mg/kg) orally for 21 days demonstrated a cure rate of 34.53%. Conclusion. The results display a correlation between the therapeutic effects of SJZT on stress-induced peptic ulcers and central neurotransmitter levels. Further to this, SJZT can inhibit the hypersecretion of HCl in the stomach, thus inhibiting stress-induced peptic ulcers.

Evaluating a community-based stroke nursing education and rehabilitation programme for patients with mild stroke.

This study evaluated whether mild stroke patients who received a community-based stroke nursing intervention had better stroke knowledge, behaviour and self-efficacy than those who were exposed to traditional education programmes. The intervention group consisted of sixty five stroke patients randomly selected from seven communities who received three 2-hour stroke interventions per week for 8 weeks. The normal care group consisted of sixty two stroke patients randomly selected from a medical centre who received a general stroke education programme. The stroke patients in two groups were assessed at baseline, after intervention and at the 6-month follow-up. At the 6-month follow-up, the intervention group demonstrated an improvement in the knowledge of stroke risk factors compared with the normal care group. Three months after education, the intervention group exhibited changes in the knowledge of stroke, social participation and self-efficacy compared with those at baseline. Also, self-efficacy was correlated with the knowledge of stroke risk factors after intervention and at the 6-month follow-up; self-efficacy was correlated with social participation after the 6-month follow-up. A community-based stroke nursing intervention might have effects on changes in the knowledge of stroke risk factors, social participation and self-efficacy.

Complicated acute motor axonal neuropathy with delayed acute respiratory distress syndrome and rapidly progressive glomerulonephritis: a case report.

PURPOSE: Acute motor axonal neuropathy (AMAN), a variant of Guillain Barre syndrome (GBS), is frequently induced by the antecedent infection of some atypical pathogen, such as Campylobacter jejuni, Mycoplasma pneumonia and some virus. It is generally accepted that corticosteroids and immunosuppressants are not recommended in patients with GBS including AMAN. However, if systemic autoimmune reaction developed, the principle of management might be changed. CASE REPORT: We report a young man who rapidly developed acute motor axonal neuropathy. Although plasma exchange had been given, the violent immunological reaction was unable to be controlled, prolonged leukemoid reaction and high level of autoimmunological titers, including C-reactive protein (CRP), rheumatoid factor (Rf), and antineutrophil cytoplasmic autoantibody (ANCA) persisted. Consequently, two months later, this patient developed acute respiratory distress syndrome (ARDS) and type 3 of rapidly progressive glomerulonephritis (RPGN) with rapid decline of renal function until immunosuppressants were given. CONCLUSION: AMAN combined with the violent systemic autoimmune reaction strongly indicated an uneven disease course and implied that only standard plasmapheresis is not sufficient and corticosteroids with immunosuppressant should be added in early stage.

Examining factors associated with pre-admission to discharge of stroke patients.

Stroke is the second leading cause of death and a major cause of adult disability in Taiwan. This research established correlations between pre-admission and discharge data in stroke patients to promote education of the general public, prevention, treatment and high standards of chronic care. A total of 790 stroke patients at Chung Shan Medical University Hospital from 2007 to 2009 contained in the Taiwan Stroke Registry were included in this study. The patients were classified into two major categories: ischemic and hemorrhagic. Thirteen variables, including time series variables, were explored. Our results showed that age, education, hours from symptom onset to the emergency department (ED) arrival, and length of stay in hospital were significantly associated with stroke incidence. These findings show the present situation and medical quality of medical care for stroke patients in Taiwan. The factors association model may assist in developing a set of improvement plans for the coming year.

Concurrent Guillain-Barré syndrome and myasthenia gravis: the first case in Taiwan.

The concurrent development of Guillain-Barré syndrome (GBS) and myasthenia gravis (MG) is rare. It has been associated with molecular mimicry between infectious agents and self-antigens. Such antibodies may show cross-reactions against both myelin proteins of peripheral nerves and acetylcholine receptors of neuromuscular junctions. Thymoma-associated multi-organ autoimmunity may also play a role in initiating autoimmune process. We present such a case with the concurrent development of GBS and MG.

Impairment of cerebral hemodynamic response to the cold pressor test in patients with Parkinson's disease.

BACKGROUND AND PURPOSE: Disturbance of the autonomic nervous system (ANS) is frequently encountered in Parkinson's disease (PD). In this study, we examined changes in systemic and cerebral hemodynamics during the cold pressor test (CPT) to determine whether cerebrovascular reactivity, controlled by the sympathetic nervous system, is intact or impaired in patients with PD. METHODS: Forty-nine patients with PD and 49 sex- and age-matched non-PD subjects were evaluated. Measurements were performed in the resting state and over a period of 1min of CPT. The cerebral blood flow velocity (CBFV) and pulsatility index (PI) of the middle cerebral artery (MCA) were recorded by transcranial color-coded Doppler ultrasonography (TCCS). Mean arterial blood pressure (MAP), heart rate (HR), and end-tidal CO(2) (Et-CO(2)) were investigated simultaneously. The resistance of the cerebrovascular bed (CVR) was calculated as the ratio of mean arterial blood pressure to mean cerebral blood flow velocity (Vm). Changes of Vm, PI and CVR in response to the cold pressor test were evaluated. RESULTS: Baseline values for control and PD subjects showed no statistical difference. CPT induced a significant increase in MAP, HR, and Vm in both groups. Pulsatility index (PI) and CVR were decreased in both groups during CPT. Percent increases of Vm (P<0.001) and MAP (P=0.011) were significantly higher while the percent decreases of PI (P=0.002) and CVR (P=0.007) were significantly decreased more in the non-PD group. CONCLUSIONS: This study indirectly shows that ANS-mediated cerebrovascular reactivity is impaired in patients with PD. Further investigations are needed to confirm the hypothesis that using the cold pressor test to evaluate cerebrovascular reactivity might be beneficial in early diagnosis of impairment of ANS-mediated cerebrovascular autoregulation in patients with PD.

Antioxidative and anti-inflammatory effects of four cysteine-containing agents in striatum of MPTP-treated mice.

OBJECTIVES: Mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used to examine the neuroprotective effects of n-acetyl cysteine (NAC), s-ethyl cysteine (SEC), s-methyl cysteine (SMC), and s-propyl cysteine (SPC). METHODS: Each agent at 1 g/L was directly added to the drinking water for 3 wk. Mice were treated by subcutaneous injection of MPTP (24 mg/kg body weight) for 6 consecutive days. The brain from each mouse was quickly removed and the striatum was collected for analyses. RESULTS: The MPTP treatment significantly depleted striatal glutathione content, reduced the activity of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase, increased malondialdehyde level, and elevated interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) levels in striatum (P < 0.05). The pre-intake of NAC, SEC, SMC, and SPC significantly attenuated MPTP-induced glutathione loss, retained the activity of GPX and SOD, diminished oxidative stress, and suppressed MPTP-induced elevation of IL-6 and TNF-alpha (P < 0.05). MPTP treatment significantly suppressed GPX mRNA expression and enhanced TNF-alpha mRNA expression (P < 0.05). Compared with MPTP treatment alone, the pre-intake of NAC, SEC, SMC, and SPC significantly elevated GPX mRNA expression and diminished TNF-alpha mRNA expression (P < 0.05), in which SPC showed the greatest suppressive effect against MPTP-induced TNF-alpha mRNA expression (P < 0.05). Dopamine and 3,4-dihydroxyphenylacetic acid contents in the striatum were significantly decreased by MPTP treatment (P < 0.05). The pre-intake of four test agents significantly improved MPTP-induced dopamine depletion and increased dopamine/3,4-dihydroxyphenylacetic acid content (P < 0.05). CONCLUSION: These results suggest that these cysteine-containing compounds could provide antioxidative and anti-inflammatory protection for the striatum against the development of Parkinson's disease.