Toughening of epoxy thermosets by self-assembled nanostructures of amphiphilic comb-like random copolymers.

Amphiphilic comb-like random copolymers synthesized from poly(ethylene glycol) methyl ether methacrylate (PEGMMA) and stearyl methacrylate (SMA) with PEGMMA contents ranging between 30 wt% and 25 wt% were demonstrated to self-assemble into various well-defined nanostructures, including spherical micelles, wormlike micelles, and vesicle-like nanodomains, in anhydride-cured epoxy thermosets. In addition, the polymer blends of the comb-like random copolymer and poly(stearyl methacrylate) were prepared and incorporated into epoxy thermosets to form irregularly shaped nanodomains. Our research findings indicate that both the comb-like random copolymers and polymer blends are suitable as toughening modifiers for epoxy. When added at a concentration of 5 wt%, both types of modifiers lead to substantial improvements in the tensile toughness (>289%) and fracture toughness of epoxy thermosets, with minor reductions in their elastic modulus (<16%) and glass transition temperature (<6.1 °C). The fracture toughness evaluated in terms of the critical stress intensity factor (KIC) and the strain energy release rate (GIC) increased by more than 67% and 131% for the modified epoxy thermosets containing comb-like random copolymers.

The correlates and reference values for the 6-minute walk distance in Taiwanese adults with schizophrenia.

PURPOSE: The study aimed to identify the factors associated with the 6-min walk distance (6MWD) and to provide reference values for the 6MWD in individuals with schizophrenia (SCZ) in Taiwan. METHODS: A proportional stratified sampling method was utilized based on distribution of gender, age and body mass index (BMI) at the study hospital. The 6-minute walk test was conducted according to the American Thoracic Society protocol. RESULTS: A total of 237 patients with SCZ completed the 6-minute walk test. The 6MWD was significantly associated with age, height, weight, and length of the onset of SCZ. Stepwise linear regression revealed that height and age were significant determinants of 6MWD. The reference values for males and females at different age groups were determined. Notably, females over 60 walked substantially shorter than the age younger than 60. CONCLUSIONS: Height and age were the main predictors for 6MWD among people with SCZ in Taiwan. The established reference values can be used to identify those at risk of poor cardiorespiratory fitness and as a target outcome during exercise programs in psychiatric rehabilitation. Our results highlight that older females with SCZ may be a priority group to target with exercise interventions to mitigate the faster decline in cardiorespiratory fitness.IMPLICATIONS FOR REHABILITATIONHeight and age were predictors of 6-min walk distance (6MWD) in schizophrenia (SCZ).The established age- and gender reference values for the 6MWD can be used to identify those at risk of poor cardiorespiratory fitness.Females with SCZ over age 60 may be a priority group to target with exercise interventions to mitigate the faster decline in cardiorespiratory fitness.

Evaluating the autonomic nervous system in patients with laryngopharyngeal reflux.

OBJECTIVES: The pathogenesis of laryngopharyngeal reflux (LPR) remains unclear. It is linked to but distinct from gastroesophageal reflux disease (GERD), which has been shown to be related to disturbed autonomic regulation. The aim of this study is to investigate whether autonomic dysfunction also plays a role in the pathogenesis of LPR. STUDY DESIGN: Case-control study. SETTING: Tertiary care center. SUBJECTS AND METHODS: Seventeen patients with LPR and 19 healthy controls, aged between 19 and 50 years, were enrolled in the study. The patients were diagnosed with LPR if they had a reflux symptom index (RSI) ≥ 13 and a reflux finding score (RFS) ≥ 7. Spectral analysis of heart rate variability (HRV) analysis was used to assess autonomic function. Anxiety and depression levels measured by the Beck Anxiety Inventory (BAI) and Beck Depression Inventory II (BDI-II) were also conducted. RESULTS: In HRV analysis, high frequency (HF) represents the parasympathetic activity of the autonomic nervous system, whereas low frequency (LF) represents the total autonomic activity. There were no significant differences in the LF power and HF power between the 2 groups. However, significantly lower HF% (P = .003) and a higher LF/HF ratio (P = .012) were found in patients with LPR, who demonstrated poor autonomic modulation and higher sympathetic activity. Anxiety was also frequently observed in the patient group. CONCLUSION: The study suggests that autonomic dysfunction seems to be involved in the pathogenesis of LPR. The potential beneficial effect of autonomic nervous system modulation as a therapeutic modality for LPR merits further investigation.

Decision making in the choice of surgical management for preauricular sinuses with different severities.

OBJECTIVES: The preauricular sinus is a common congenital abnormality of the preauricular soft tissues. Here, we demonstrate the decision making in the choice of surgical management of preauricular sinuses based on disease severity. In addition, a method termed figure 8 incision with extended fistulectomy is introduced. STUDY DESIGN: Case series with chart review. SETTING: Tertiary care center. SUBJECTS: Between January 2003 and February 2010, a total of 90 patients (109 ears) underwent surgery for preauricular sinuses in our hospital. METHODS: After controlling the infection, the patients received definite surgery. They were classified into 3 groups according to the operative methods. We recorded the clinical conditions and any recurrences during the follow-up period. RESULTS: Group I patients (48 ears) had a trace inflammatory condition and underwent a simple sinusectomy. The recurrence rate was 2.08%. Group II (31 ears) and group III (30 ears) patients had more highly inflamed tissue and underwent a local wide excision and a figure 8 incision with extended fistulectomy, respectively. The recurrence rate in group II was 22.58%. Meanwhile, none of the group III cases showed a recurrence. In our study, there were 8 recurrent cases in 109 ears, yielding a recurrence rate of 7.34%. CONCLUSION: Simple sinusectomy is an adequate surgical technique for preauricular sinuses with a mild inflammatory condition. For more severe cases, the figure 8 incision with extended fistulectomy can achieve adequate wound exposure for radical excision of the inflamed tissue and a satisfactory surgical outcome.

Differential expression of LvHSP60 in shrimp in response to environmental stress.

Previous studies showed that heat-shock protein 60 (HSP60) was known to function as a molecular chaperone and is an important factor in the innate immune system in mammals. However, little was known about the physiological relevance of HSP60 in marine invertebrates. This study focuses on long-term monitoring of the differential expression of LvHSP60 in shrimp Litopenaeus vannamei in response to environmental stress. The thermal aggregation assay elucidated that LvHSP60 was an effective chaperone. It also suggested that LvHSP60 may employ the cell's intrinsic mechanism to start the immunizing process. Using quantitative real-time PCR to monitor gene expression showed that LvHSP60 was variable under different stresses including environmental stress and pathogenic infection. LvHSP60 was speculated to regulate the adaptive responses to overcome environmental stresses. In conclusion, our study proved that LvHSP60 plays an important role in the intrinsic immune system and stress responses of shrimp.