Tickling the heart: integrating social emotional learning into medical education to cultivate empathetic, resilient, and holistically developed physicians

Objectives

Advancements in technology have improved healthcare quality but shifted the focus to efficiency, negatively impacting patient- doctor relationships. This study proposes integrating social-emotional learning (SEL) into medical education to address this issue.

Key arguments

Social-emotional learning (SEL) is based on social learning theory and has a focus on emotion management, stress management, empathy, and social skills. Through SEL, students can develop social and emotional skills by observing, interacting with, and imitating others. Incorporating SEL into medical education would ensure that physicians develop the social and emotional skills necessary to form positive relationships with patients and to cope with the emotional demands of medical work. SEL comprises six domains, namely, the cognitive, emotion, social, values, perspective, and identity domains. These six domains are closely related to the six core competencies the Accreditation Council for Graduate Medical Education (ACGME) indicated every doctor should possess, which indicates that the domains of SEL are highly relevant within the context of medical education. Furthermore, SEL can lead to the development of empathy, which can improve physicians' ability to understand patients' perspectives and emotions, and resilience, which can enable physicians to more effectively cope with the demands of their work, and it can lead to holistic development, with doctors gaining an understanding of both the technical and humanistic aspects of their work.

Conclusion

Incorporating SEL in medical education would enable doctors to develop key social and emotional skills that would improve their ability to provide holistic medical services and therefore would improve overall medical systems.

Application of project-based service-learning courses in medical education: trials of curriculum designs during the pandemic

BACKGROUND

Due to COVID-19, face-to-face service activities in service-learning courses have become unfeasible. To address this challenge, this study aims to integrate project-based learning into medical education's service-learning curriculum. This study also seeks to evaluate the effectiveness of this instructional approach and identify factors that influence its success.

METHODS

A total of 135 first-year medical students enrolled in a mandatory 1-credit service-learning course were recruited. The course involved various service activities aligned with the needs of the local community. The students were organized into 12 groups, each working on different service-learning projects, such as raising health awareness or educating the public about specific diseases. Following the completion of the course, a questionnaire was distributed among the students to gather feedback on the course, and 122 (valid responses were collected, representing a response rate of 90.3%).

RESULTS

The results indicated that the project-based service-learning course significantly improved students' "interpersonal communication skills," their ability to "learn and grow from work," and their sense of "professionalism" (all p ≤ 0.037). Among the various aspects of service learning, the highest agreement was observed for "executing the project," followed by "group discussions and project formulation," "overall course review," "review of project outcomes," "outcome presentations," "teaching proposal writing and project brainstorming," "sharing of service-learning experiences by teachers," and "sharing of service-learning experiences by teaching assistants." Students also found certain factors to be beneficial in enhancing the learning effectiveness of service-learning courses, including "prize money for service-learning outcomes," "funding for service-learning activities," and "consultations from medical personnel" (all p ≤ 0.01). However, "course credit" and "photography software" did not show significant effects (both p > 0.05). The most preferred resources or activities for future service-learning courses were "course credit" and "face-to-face service-learning activities."

CONCLUSIONS

The project-based learning method improved the learning effectiveness in service-learning courses. Students perceived that the number of course credits reflects the course value and plays a pivotal role in enhancing the learning effectiveness in service-learning courses. During the epidemic, students still expect to have face-to-face service activities in service-learning courses. Therefore, without the impact of the epidemic, service learning courses should return to face-to-face service activities.

Calycosin inhibits gemcitabine-resistant lung cancer cells proliferation through modulation of the LDOC1/GNL3L/NFκB

Lung cancer is the most common malignant cancer worldwide. Combination therapies are urgently needed to increase patient survival. Calycosin is a phytoestrogen isoflavone that has been reported previously to inhibit tumor cell growth, although its effects on lung cancer remain unclear. The aim of this study was to investigate the effects of calycosin on cell proliferation and apoptosis of gemcitabine-resistant lung cancer cells. Using calycosin to treat human lung cancer cells (CL1-0) and gemcitabine-resistant lung cancer cells (CL1-0 GEMR) and examine the effects on the cells. Cultured human lung cancer cells (CL1-0) and gemcitabine-resistant lung cancer cells (CL1-0 GEMR) were treated with increasing concentrations of calycosin. Cell viability and apoptosis were studied by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide, flow cytometry, and TUNEL assays. Western blots were used to measure the expression levels of proliferation-related proteins and cancer stem cell proteins in CL1-0 GEMR cells. The results showed that calycosin treatment inhibited cell proliferation, decreased cell migration ability, and suppressed cancer stem cell properties in CL1-0 GEMR cells. Interestingly, in CL1-0 GEMR cells, calycosin treatment not only increased LDOC1 but also decreased GNL3L/NFκB protein levels and mRNA levels, in concentration-dependent manners. We speculate that calycosin inhibited cell proliferation of the gemcitabine-resistant cell line through regulating the LDOC1/GNL3L/NFκB pathway.

Diosgenin Attenuates Myocardial Cell Apoptosis Triggered by Oxidative Stress through Estrogen Receptor to Activate the PI3K/Akt and ERK Axes

Cardiovascular diseases in post-menopausal women are on a rise. Oxidative stress is the main contributing factor to the etiology and pathogenesis of cardiovascular diseases. Diosgenin, a member of steroidal sapogenin, is structurally similar to estrogen and has been shown to have antioxidant effects. Therefore, we aimed to investigate the effects of diosgenin in preventing oxidation-induced cardiomyocyte apoptosis and assessed its potential as a substitute substance for estrogen in post-menopausal women. Apoptotic pathways and mitochondrial membrane potential were measured in H9c2 cardiomyoblast cells and neonatal cardiomyocytes treated with diosgenin for 1[Formula: see text]h prior to hydrogen peroxide (H₂O₂) stimulation. H₂O₂-stimulated H9c2 cardiomyoblast cells displayed cytotoxicity and apoptosis via the activation of both Fas-dependent and mitochondria-dependent pathways. Additionally, it led to the instability of the mitochondrial membrane potential. However, the H₂O₂-induced H9c2 cell apoptosis was rescued by diosgenin through IGF1 survival pathway activation. This led to the recovery of the mitochondrial membrane potential by suppressing the Fas-dependent and mitochondria-dependent apoptosis. Diosgenin also inhibited H₂O₂-induced cytotoxicity and apoptosis through the estrogen receptor interaction with PI3K/Akt and extracellular regulated protein kinases 1/2 activation in myocardial cells. In this study, we confirmed that diosgenin attenuated H₂O₂-induced cytotoxicity and apoptosis through estrogen receptors-activated phosphorylation of PI3K/Akt and ERK signaling pathways in myocardial cells via estrogen receptor interaction. All results suggest that H₂O₂-induced myocardial damage is reduced by diosgenin due to its interaction with estrogen receptors to decrease the damage. Herein, we conclude that diosgenin might be a potential substitute substance for estrogen in post-menopausal women to prevent heart diseases.

Insulin-like growth factor II receptor alpha overexpression in heart aggravates hyperglycemia-induced cardiac inflammation and myocardial necrosis

Diabetes-induced cardiovascular complications are mainly associated with high morbidity and mortality in patients with diabetes. Insulin-like growth factor II receptor α (IGF-IIRα) is a cardiac risk factor. In this study, we hypothesized IGF-IIRα could also deteriorate diabetic heart injury. The results presented that both in vivo transgenic Sprague-Dawley rat model with specific IGF-IIRα overexpression in the heart and in vitro myocardium H9c2 cells were used to investigate the negative function of IGF-IIRα in diabetic hearts. The results showed that IGF-IIRα overexpression aided hyperglycemia in creating more myocardial injury. Pro-inflammatory factors, such as Tumor necrosis factor-alpha, Interleukin-6, Cyclooxygenase-2, Inducible nitric oxide synthase, and Nuclear factor-kappaB inflammatory cascade, are enhanced in the diabetic myocardium with cardiac-specific IGF-IIRα overexpression. Correspondingly, IGF-IIRα overexpression in the diabetic myocardium also reduced the PI3K-AKT survival axis and activated mitochondrial-dependent apoptosis. Finally, both ejection fraction and fractional shortening were be significantly decrease in diabetic rats with cardiac-specific IGF-IIRα overexpression. Overall, all results provid clear evidence that IGF-IIRα can enhance cardiac damage and is a harmful factor to the heart under high-blood glucose conditions. However, the pathophysiology of IGF-IIRα under different stresses and its downstream regulation in the heart still require further research.

Garcinol protects SH-SY5Y cells against MPP+-induced cell death by activating DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway in sequential stimulation of p-AMPK mediated autophagy

Parkinson's disease (PD), a chronic and progressive neurodegenerative disease, can reduce the population of dopaminergic neurons in the substantia nigra. The cause of this neuronal death remains unclear. 1-Methyl-4-phenylpyridinium ion (MPP+) is a potent neurotoxin that can destroy dopaminergic (DA) neurons and promote PD. Garcinol, a polyisoprenylated benzophenone derivative, was extracted from Garcinia indica and is an important active compound it has been used as an anticancer, antioxidant, and anti-inflammatory, agent and it can suppress reactive oxygen species (ROS) mediated cell death in a PD model. Human neuroblastoma (SH-SY5Y) cells (1 × 10⁵  cells) were treated with MPP+ (1 mM) for 24 h to induce cellular ROS production. The formation of ROS was suppressed by pretreatment with different concentrations of garcinol (0.5 and 1.0 μM) for 3 h in SH-SY5Y cells. The present study found that MPP+ treatment increased the formation of reactive oxygen species (ROS), and the increased ROS began to promote cell death in SH-SY5Y cells. However, our natural compound garcinol effectively blocked MPP+-mediated ROS formation by activating the DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway. Further findings indicate that the activated SIRT1 can also regulate p-AMPK-mediated autophagy to protect the neurons from the damage it concludes that garcinol sub-sequential regulates intracellular autophagy in this model, and the productive efficacy of garcinol was confirmed by western blot analysis and MitoSOX DCFDA and MTT assays. The results showed garcinol increased protection due to the prevention of MPP+-induced ROS and the promotion of cell survival.

Ginkgolide A improves the pleiotropic function and reinforces the neuroprotective effects by mesenchymal stem cell-derived exosomes in 6-OHDA-induced cell model of Parkinson's disease

Parkinson's disease (PD) is a common disorder attributed to the loss of midbrain dopamine (mDA) neurons and reduced dopamine secretion. Currently, the treatment regimes for PD comprise deep brain stimulations, however, it attenuates the PD progression marginally and does not improve neuronal cell death. We investigated the function of Ginkgolide A (GA) to reinforce Wharton's Jelly-derived mesenchymal stem cells (WJMSCs) for treating the in vitro model of PD. GA enhanced the self-renewal, proliferation, and cell homing function of WJMSCs as assessed by MTT and transwell co-culture assay with a neuroblastoma cell line. GA pre-treated WJMSCs can restore 6-hydroxydopamine (6-OHDA)-induced cell death in a co-culture assay. Furthermore, exosomes isolated from GA pre-treated WJMSCs significantly rescued 6-OHDA-induced cell death as determined by MTT assay, flow cytometry, and TUNEL assay. Western blotting showed that apoptosis-related proteins were decreased following GA-WJMSCs exosomal treatment which further improved mitochondrial dysfunction. We further demonstrated that exosomes isolated from GA-WJMSCs could restore autophagy using immunofluorescence staining and immunoblotting assay. Finally, we used the alpha-synuclein recombinant protein and found that exosomes derived from GA-WJMSCs led to the reduced aggregation of alpha-synuclein compared to that in control. Our results suggested that GA could be a potential candidate for strengthening stem cell and exosome therapy for PD.

Cryptotanshinone protects against oxidative stress in the paraquat-induced Parkinson's disease model

Parkinson's disease (PD) is a common neurodegenerative disorder associated with striatal dopaminergic neuronal loss in the Substantia nigra. Oxidative stress plays a significant role in several neurodegenerative diseases. Paraquat (PQ) is considered a potential neurotoxin that affects the brain leading to the death of dopaminergic neurons mimicking the PD phenotype. Various scientific reports have proven that cryptotanshinone possesses antioxidant and anti-inflammatory properties. We hypothesized that cryptotanshinone could extend its neuroprotective activity by exerting antioxidant effects. This study was designed to evaluate the effects of cryptotanshinone in both cellular and animal models of PQ-induced PD. Annexin V-PI double staining and immunoblotting were used to detect apoptosis and oxidative stress proteins, respectively. Reactive oxygen species kits were used to evaluate oxidative stress in cells. For in vivo studies, 18 B6 mice were divided into three groups. The rotarod data revealed the motor function and immunostaining showed the survival of TH+ neurons in SNpc region. Our study showed that cryptotanshinone attenuated paraquat-induced oxidative stress by upregulating anti-oxidant markers in vitro, and restored behavioral deficits and survival of dopaminergic neurons in vivo, demonstrating its therapeutic potential.

Effects of Swimming Pool Conditions and Floor Types on White Roman Geese's Physical Condition Scores and Behaviors in an Indoor Rearing System

Biosecurity problems, including the continual risk of avian influenza spread by wild birds, have severely affected traditional free-range waterfowl production systems. Regulations and techniques for indoor goose production require more considerations for animal welfare. This study investigated the effects of swimming pool conditions and different floor types on the physical condition scores and behaviors of indoor-reared White Roman geese. A total of 48 male and 48 female White Roman geese reared from the age of 15 to 84 days were randomly allocated to pens with or without a swimming pool and with either mud or perforated plastic floors. Providing a swimming pool improved geese's eye and feather cleanliness and breast blister scores at the age of 84 days. Compared with geese reared on a mud floor, those reared on a perforated plastic floor had better feather cleanliness and higher breast blister scores at the age of 56 and 84 days. Providing a swimming pool to indoor-reared geese may reduce the proportion of abnormal behaviors, such as injurious feather pecking, by increasing water-related behaviors. This study suggests a more appropriate environment design for better balancing commercial goose production with animal welfare in an indoor rearing system.

Qualitative study of the learning and studying process of resident physicians in China

BACKGROUND

Clinical medical education is essential in physician training. This study developed recommendations for medical residency course design on the basis of the perspectives of learners in China and how they interact with their environment. The central research topic was the professional development and learning process of residents, including the obstacles that hinder and factors that promote their learning, their views on existing teaching methods, interaction between teachers and medical teams, and suggestions for designing future residency training programs.

METHODS

This study had a qualitative research design. Interviews were conducted between July and October 2019 with 17 specialist residents and 12 assistant general practitioner residents from the department of education of the hospital. The participants were recruited from Qingyuan People's Hospital in Guangdong Province, China. The interview outlines focused on the following four themes: clinical learning experiences and reflections on learning, experience of interaction with patients, experience of working with other medical personnel, and future learning directions.

RESULTS

To overcome challenges in clinical learning, the residents mainly learned from their teachers and focused specifically on their own experiences. Regarding teaching methods and designs in clinical medicine, the residents preferred large-group, small-group, and bedside teaching and reported that bedside teaching enables the resolution of clinical problems, initiates self-learning, and improves diagnostic thinking. They disliked teachers with low teaching motivation or who were reluctant to interact with them and favored teachers who had strong teaching skills and respect for their students.

CONCLUSIONS

The residents suggested that clinical and active learning must be the main learning method for developing general medical competencies. Residency training must be conducted in an environment that facilitates residents' learning and meaningful learning activities. The interdependent symbiotic relationships in the education ecosystem can serve as a reference for designing residency courses.

Extensively Reducing Interfacial Resistance by the Ultrathin Pt Layer between the Garnet-Type Solid-State Electrolyte and Li-Metal Anode

All-solid-state Li-ion batteries (ASSLIBs), also known as next-generation batteries, have attracted much attention due to their high energy density and safety. The best advantage of ASSLIBs is the Li-metal anodes that could be used without safety issues. In this study, a highly conductive garnet solid electrolyte (Li_6.75La₃Zr_1.75Ta_0.25O₁₂, LLZTO) was used in the ASSLIB, and a Pt film was used to modify the surface of LLZTO to prove the solution of the Li-metal anode for LLZTO. Li-Pt alloy was synthesized to improve the wettability and contact of the interface. The interfacial resistance was reduced by 21 times, at only 9 Ω cm². The symmetric cell could stably cycle over 3500 h at a current density of 0.1 mA cm^-2. The full cell of Li|Li-Pt|LLZTO|LiFePO₄ and Li|Li-Pt|LLZTO|LiMn_0.8Fe_0.2PO₄ achieved high stability in terms of battery performance. Point-to-point contact transformed into homogeneous surface contact made the Li-ion flux faster and more stable. This surface modification method could provide researchers with a new choice for fixing interface issues and promoting the application of high-performance ASSLIBs in the future.

Leech extract: A candidate cardioprotective against hypertension-induced cardiac hypertrophy and fibrosis

ETHNOPHARMACOLOGICAL RELEVANCE

The prevalence of cardiovascular diseases (CVDs) has been increasing worldwide. Despite significant improvements in therapeutics and on-going developments of novel targeted-treatment regimens, cardiac diseases lack effective preventive and curative therapies with minimal side effects. Therefore, there is an urgent need to identify and propagate alternative and complementary therapies against cardiovascular diseases. Some traditional Chinese medicines can contribute to the prevention and treatment of CVDs and other chronic diseases, with few side effects. Hirudo, a medicinal leech, has been acclaimed for improving blood circulation and overcoming blood stagnation; however, the precise molecular mechanisms of leech extract treatment against pathological cardiac remodeling remain elusive. In this study, we aimed to delineate the molecular mechanisms of medicinal leech extract in the treatment of cardiac hypertrophy and fibrosis, using both in vitro and in vivo assessments.

MATERIALS AND METHODS

We conducted in vitro and in vivo animal experiments, including cell-viability assays, fluorescence microscopy, immunoblotting, immunohistochemistry, and Masson's trichrome staining.

RESULTS

Pre-treatment with leech extract conferred a survival benefit to spontaneously-hypertensive rats (SHRs) and significantly reduced angiotensin II (ANG II)-induced cardiac hypertrophy and fibrosis. ANG II-stimulated cardiac hypertrophy markers were attenuated by leech extract treatment, versus controls. Translational expression of stress-associated mitogen-activated protein kinases (MAPKs) was also repressed. In vivo, leech extract treatment significantly ameliorated the cardiac hypertrophy phenotype in SHRs and diminished interstitial fibrosis, accompanied with reduced fibrosis markers.

CONCLUSION

Leech extract treatment under a hypertensive condition exerted significant cardio-protective benefits by reducing the expression of cardiac hypertrophy-related transcription factors, stress-associated MAPKs, and fibrosis mediators. Our findings imply that medicinal leach extract may be effective against hypertension-induced cardiac hypertrophy and fibrosis.

Matchmaker of Marriage between a Li Metal Anode and NASICON-Structured Solid-State Electrolyte: Plastic Crystal Electrolyte and Three-Dimensional Host Structure

The marriage between a Li metal anode and the solid-state electrolyte is expected to limit the safety risk of secondary batteries. However, dendrites and interfacial stability hinder the combination of Li metal anode and solid-state electrolyte. Herein, a plastic crystal electrolyte (PCE) and three-dimensional (3D) host structure played the role of a matchmaker in combining the solid-state electrolyte and Li metal anode. Succinonitrile cooperated with Li salt and Li_6.4La₃Zr_1.4Ta_0.6O₁₂ nanosize powder and built a PCE interphase, which enhanced the interfacial stability between Li_1.5Al_0.5Ge_1.5(PO₄)₃ and Li metal anode. To protect the soft PCE from the dendrite penetration, commercially sold Super P, carbon nanotube, KS6, and Ketjen black were co-heated with the melted Li metal. However, only KS6 built a 3D host in Li metal successfully because of its high graphitization and layered structure. Benefitting from the matchmakers, the solid-state batteries exhibited enhanced cycling stability.

Patients with chronic urticaria have a higher risk of psychiatric disorders: a population-based study

BACKGROUND

The prevalence of psychiatric comorbidities in patients with chronic urticaria (CU) in a national population is largely unknown.

OBJECTIVES

To investigate the prevalence of psychiatric disorders and psychiatric medication use in patients with CU in Taiwan.

METHODS

Data were sourced from Taiwan's National Health Insurance Research Database for 2011. Patients who had a primary/secondary International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code of 708·1, 708·8 or 708·9 during 2011 with at least two outpatient visits and an antihistamine prescription were identified as CU cases. Patients with CU were classified into three disease severity groups according to their medication types. Psychiatric disorders were identified by patients having three outpatient visits with a primary or secondary diagnosis of a given psychiatric disease. Psychiatric medication use was defined by having at least four outpatient visits with prescriptions for anxiolytics, antidepressants or sleeping pills in 2010 or 2011.

RESULTS

Of the 167 132 patients with CU, 82·5% had mild CU, 17·0% had moderate CU and 0·4% had severe CU. Patients with CU had a higher prevalence of psychiatric disorders and psychiatric medication prescription than control groups. The relative risk (RR) of psychiatric disorders was 1·43 for patients with mild, 1·50 for patients with moderate and 2·32 for patients with severe CU vs. the controls (P < 0·001). For psychiatric medication prescription, the RRs were 1·95, 2·70 and 2·09, respectively, vs. controls (P < 0·001).

CONCLUSIONS

Patients with CU had a higher prevalence and risk of psychiatric disorders and psychiatric medication prescription than control groups. What's already known about this topic? Previous studies have shown a high prevalence of psychiatric comorbidities in patients with chronic urticaria (CU), with rates ranging from 35% to 60%. Anxiety, depression and somatoform disorders have been reported as the most prevalent mental disorders in patients with CU. What does this study add? Patients with CU had a higher prevalence of psychiatric disorders and psychiatric medication use than control groups in the general population. The relative risk (RR) of psychiatric disorders was 1·43 for those with mild CU, 1·50 for those with moderate CU and 2·32 for those with severe CU vs. controls. The RR for psychiatric medication use was 1·95 for those with mild CU, 2·70 for those with moderate CU and 2·09 for those with severe CU vs. controls. Mental health evaluations and management are important elements in CU management.

Ramipril and resveratrol co-treatment attenuates RhoA/ROCK pathway-regulated early-stage diabetic nephropathy-associated glomerulosclerosis in streptozotocin-induced diabetic rats

Clinical studies have shown that hyperglycemia can induce early-stage diabetic nephropathy (DN). Furthermore, oxidative stress, tubular epithelial-mesenchymal transition and extracellular matrix accumulation promote the progression of DN to chronic kidney disease and tubulointerstitial fibrosis. It is necessary to initiate treatment at the early stages of DN or even during the early stages of diabetes. In this work, rats with streptozotocin (STZ)-induced diabetes mellitus (DM) presented early DN symptoms within 45 days, and collagen accumulation in the glomerulus of the rats was primarily mediated through the RhoA/ROCK pathway instead of the TGF-β signaling pathway. Resveratrol (15 mg/kg/day) and ramipril (10 mg/kg/day) co-treatment of STZ-induced DN rats showed that glomerulosclerosis in early-stage DN was reversible (P < .05 compared with that in STZ-induced DM rats). The results of this study support early intervention in diabetes or DN as a more efficient therapeutic strategy.

Anti-Apoptosis and Anti-Fibrosis Effects of Eriobotrya Japonica in Spontaneously Hypertensive Rat Hearts

Myocardial apoptosis and fibrosis represent important contributing factors for development of hypertension-induced heart failure. The present study aims to investigate the potential effects of Eriobotrya japonica leaf extract (EJLE) against hypertension-induced cardiac apoptosis and fibrosis in spontaneously hypertensive rats (SHRs). Twelve-week-old male rats were randomly divided into four different groups; control Wistar Kyoto (WKY) rats, hypertensive SHR rats, SHR rats treated with a low dose (100 mg/kg body weight) of EJLE and SHR rats treated with a high dose (300 mg/kg body weight) of EJLE. Animals were acclimatized for 4 weeks and thereafter were gastric fed for 8 weeks with two doses of EJLE per week. The rats were then euthanized following cardiac functional analysis by echocardiography. The cardiac tissue sections were examined by Terminal Deoxynucleotidyl Transferase-Mediated Deoxyuridine Triphosphate (dUTP) Nick End-Labeling (TUNEL) assay, histological staining and Western blotting to assess the cardio-protective effects of EJ in SHR animals. Echocardiographic measurements provided convincing evidence to support the ability of EJ to ameliorate crucial cardiac functional characteristics. Furthermore, our results reveal that supplementation of EJLE effectively attenuated cardiac apoptosis and fibrosis and also enhanced cell survival in hypertensive SHR hearts. Thus, the present study concludes that EJLE potentially provides cardio-protective effects against hypertension-induced cardiac apoptosis and fibrosis in SHR animals.

Treatment with 17β-Estradiol Reduced Body Weight and the Risk of Cardiovascular Disease in a High-Fat Diet-Induced Animal Model of Obesity

Estrogen receptor α (ERα) and estrogen receptor β (ERβ) play important roles in cardiovascular disease (CVD) prevention. Recently, these estrogen receptors were reconsidered as an important treatment target of obesity leading to CVD. In this study, 17β-estradiol (17β-E) replacement therapy applied to high-fat diet-induced obese C57B male mice and ovariectomized (OVX) rats were evaluated, and the protective effects against high-fat diet-induced obesity were assessed in C57B mouse hearts. The results showed that 17β-E treatment activated both ERα and ERβ, and ERβ levels increased in a dose-dependent manner in high-fat diet C57B mouse cardiomyocytes following 17β-E treatment. Notably, an almost 16% reduction in body weight was observed in the 17β-E-treated (12 μg/kg/day for 60 days) high-fat diet-induced obese C57B male mice. These results suggested that 17β-E supplements may reduce CVD risk due to obesity.

Boosted photocatalytic efficiency through plasmonic field confinement with bowtie and diabolo nanostructures under LED irradiation

Photoresist and electron beam lithography techniques were used to fabricate embedded Ag bowtie and diabolo nanostructures with various apex angles on the surface of a TiO₂ film. The reinforced localized surface plasmon resonance (LSPR) and electric field generated at both the Ag/TiO₂ and air/TiO₂ interfaces enabled high light absorbance in the TiO₂ nanostructure. Results for both the bowtie and diabolo nanostructures showed that a reduction in the apex angle enhances both LSPR and Raman intensity. The maximum electric current density observed at the apex indicates that the strongest SPR confines at the tip gap of the bowtie and corners of the diabolo. In a long-wavelength region, as the apex angle increases, the resonant peak wavelength of the standing wave matches the increased length of the prism edges of the bowtie and diabolo to create a redshift. In a short-wavelength region, as the apex angle increases, the blueshift of the resonant peak wavelength is presumably attributable to the increase in the effective index of the local surface plasmon polariton standing wave mainly residing along both the bowtie and diabolo axes. The redshift and blueshift trend in the simulation results for the resonant peak wavelength agrees well with the experimental results. The fastest photocatalytic rate was obtained by placing the Ag/TiO₂ bowtie at an apex angle of 30° in the methylene blue solution, revealing that the plasmonic photocatalysis causes the highest degradation efficiency. This is because the Schottky junction and LSPR can stimulate many valid radicals for the environmental improvement.

Crystallographic origin of cycle decay of the high-voltage LiNi0.5Mn1.5O4 spinel lithium-ion battery electrode

Crystallographic structural study of the capacity decay of the LiNi_0.5Mn_1.5O₄||Li₄Ti₅O₁₂ 18650-type battery using operando neutron powder diffraction.

Conduction control at ferroic domain walls via external stimuli

Intriguing functionalities at nano-sized domain walls have recently spawned a new paradigm for developing novel nanoelectronics due to versatile characteristics. In this study, we explore a new scenario to modulate the local conduction of ferroic domain walls. Three controlling parameters, i.e., external electrical field, magnetic field and light, are introduced to the 90° domain walls (90° DWs) of BiFeO₃. Electrical modulation is realized by electrical transport, where the mobility of 90° DWs can be altered by gating voltage. We further use the ferromagnetic/antiferromagnetic coupling to reveal the inherent magnetism at the DWs. With an established magnetic nature, magnetotransport has been conducted to introduce magnetic controlling parameter, where a giant positive magnetoresistance change can be observed up to 200%. In addition, light modulated conduction, a core factor for multifunctional applications, is successfully demonstrated (current enhancement by a factor of 2 with 11 W white lamp). These results offer new insights to discover the tunability of domain wall nanoelectronics.

Antidepressant-associated mania: soon after switch from fluoxetine to mirtazapine in an elderly woman with mixed depressive features

Mirtazapine augmentation to a serotonin-reuptake inhibitor has been proposed to boost antidepressant effects and more likely to induce manic switch. Such a combined antidepressant therapy strategy should be used carefully if the patient's refractoriness is attributable to mixed depressive features. Mixed depression is more difficult to be treated by antidepressant monotherapy and related to higher risk of manic switch during treatment. We report a case with no previous history of bipolar disorder, whereas developed full-blown psychotic manic symptoms soon after switch from fluoxetine to mirtazapine. The patient's premorbid characters and clinical presentations suggested an implicit bipolarity that predisposed her to a manic switch. Her manic switch was likely to be triggered by a simulated combined effect because of complex drug interactions during shifting from fluoxetine to mirtazapine. For patients in mixed depressive states, mood stabilizers are preferable to antidepressants.

A highly stable nonbiofouling surface with well-packed grafted zwitterionic polysulfobetaine for plasma protein repulsion

An ideal nonbiofouling surface for biomedical applications requires both high-efficient antifouling characteristics in relation to biological components and long-term material stability from biological systems. In this study we demonstrate the performance and stability of an antifouling surface with grafted zwitterionic sulfobetaine methacrylate (SBMA). The SBMA was grafted from a bromide-covered gold surface via surface-initiated atom transfer radical polymerization to form well-packed polymer brushes. Plasma protein adsorption on poly(sulfobetaine methacrylate) (polySBMA) grafted surfaces was measured with a surface plasmon resonance sensor. It is revealed that an excellent stable nonbiofouling surface with grafted polySBMA can be performed with a cycling test of the adsorption of three model proteins in a wide range of various salt types, buffer compositions, solution pH levels, and temperatures. This work also demonstrates the adsorption of plasma proteins and the adhesion of platelets from human blood plasma on the polySBMA grafted surface. It was found that the polySBMA grafted surface effectively reduces the plasma protein adsorption from platelet-poor plasma solution to a level superior to that of adsorption on a surface terminated with tetra(ethylene glycol). The adhesion and activation of platelets from platelet-rich plasma solution were not observed on the polySBMA grafted surface. This work further concludes that a surface with good hemocompatibility can be achieved by the well-packed surface-grafted polySBMA brushes.

A missing data treatment for data mining applications in medical information systems

To apply user-friendly, easily operated and accessible tools to handle missing data resulting from an auto-stored medical information system, these tools are applied to satisfy general users from different disciplines (i.e. statistics and machine-learning), followed by medical information system development. This study attempts to develop a new logic separation inference method applied to a database with a format like most real-world medical records containing many missing data and miscellaneous variables. It is expected that this method should have better performance than currently accessible methods. The newly developed logic separation inference method shows a classification power of 0.997 (elimination method is 1), which is better than the simple replacing method (replaced by mode shows 0.974). Both inference methods (mode and mean) have superior classification power to the simple replacing method. The missing data treatment processes introduced in this study can be completed on a MS Excel spreadsheet without any complicated calculation; therefore, they can satisfy general users. This new missing data treatment method is only applied up to 60% of the missing data (missing at random). However, when there is large amount of data, it is expected that this method also can be applied to a database missing more than 60%.

Data mining techniques applied to medical information

Knowledge discovery from the dramatically increased data of an auto-stored medical information system is still in its infancy. The purpose of this study is to use widely available and easily operated techniques that can satisfy general users in extracting specific knowledge to make the medical information system more functional. Data mining techniques, including data visualisation, correlation analysis, discriminant analysis, and neural networks supervised classification, were applied to heart disease databases. These techniques can help to identify high risk patients, define the most important factors (variables) in heart disease, and build a multivariate relationship model to show the relationship between any two variables in a way that such relationships are easy to view. Simple visualization techniques were utilised to construct this model, which corresponds with current medical knowledge. Two nonparametric (distribution assumption free) classification tools were employed to identify high risk heart disease patients. Both the neural networks supervised classification methods and the discriminant analysis method produced reliable classification rates for heart disease patients. However, neural networks yielded a higher percentage of correct classifications (averaging 89%) than discriminant analysis (79%). Data visualisation and correlation analysis resulted in similar conclusions regarding the most important factors in heart disease. These data mining tools provide simple and effective methods of extracting knowledge from general medical information. The treatment of missing data is also discussed.

Low dose desferrioxamine can improve erythropoiesis in iron-overload hemodialysis patients without side effects

OBJECTIVE

Multiple blood transfusions were often required to treat anemia in uremia patients before the era of recombinant human erythropoietin (r-HuEPO). Iron overload thus frequently occurred in chronic hemodialysis patients. Desferrioxamine (DFO) is an effective chelating agent, which can remove excessive iron and can enhance erythropoiesis. Large dose DFO treatment is a therapy associated with the development of severe complications. In this study, a low dose DFO regime was used to treat iron overloaded hemodialysis patients. The efficacy and side effects of this regiment were evaluated.

MATERIALS AND METHODS

Eight iron overloaded chronic hemodialysis patients were enrolled in this study. All patients received DFO 500 mg intravenously twice-a-week for eight months. Serum aluminum, transferrin saturation (TFS) and r-HuEPO requirement were recorded before and after DFO treatment. Serum ferritin and hematocrit (Hct) were measured before, during, and after the DFO withdrawal period. All patients were evaluated and followed closely during treatment.

RESULTS

Changes in aluminum, TFS and r-HuEPO dosage were unremarkable (p > 0.05). Hct increased significantly after eight months of DFO treatment (from 25.3% to 27.0%, p < 0.05). Ferritin level was reduced by 43.2% at the end of treatment and an evident decline of ferritin was achieved after four months of treatment (2102 ng/mL to 1166 ng/mL, p < 0.05). All patients tolerated the treatment well and no complications were found.

CONCLUSION

Low dose DFO can chelate iron effectively in chronic hemodialysis patients. This treatment can enhance erythropoiesis without adverse effects.

The significance of syphilis serology tests on long-term hemodialysis patients

BACKGROUND

Syphilis is a sexually transmitted disease. Blood transfusion and blood contact are also routes of infection. Patients on long-term hemodialysis are at risk during their therapy. The aim of this study is to investigate the incidence of syphilis in hemodialysis patients, possible nosocomial infection and methods of treatment.

MATERIALS AND METHODS

A total of 556 uremic patients on maintenance hemodialysis at our hospital on June 1996 were enrolled in the study. They all received syphilis screening tests. The rapid plasma reagin (RPR) test was used as the primary screening tests and Treponema pallidum hemagglutination assay (TPHA) test as the confirmation test. According to the test results, patients were classified into false and true-positive groups. The titer of both tests were recorded. The patients in the true-positive group were further divided into the untreated and treated group depending on whether they had already received treatment. The serial change of RPR test titer of the treated group was reviewed.

RESULTS

Thirty-one patients (5.6%) had positive RPR test results and 10 patients (1.8%) had false-positive results. The titers of both RPR and TPHA tests were rather low in the positive groups. Most of the confirmed syphilis patients were asymptomatic and diagnosed serologically. In the treated group, the RPR test titer did not show significant decline and no seroconversion was noted after treatment.

CONCLUSION

We observed that infectious syphilis patients exist in our hemodialysis unit and survey for this disease is necessary. The titers of both positive RPR and TPHA tests are low. Most diagnosed patients had latent syphilis, and serologic response to treatment is probably the same as in general population.

Spontaneous cellulitis in adults with idiopathic nephrotic syndrome

BACKGROUND

Susceptibility to infection is a common problem in a patient with nephrotic syndrome. The spontaneous cellulitis is not uncommon in pediatric patients with nephrotic syndrome, whereas there have been few cases reported in adults. In order to clarify the clinical course of this complication, we present 17 adult idiopathic nephrotic patients with spontaneous cellulitis.

MATERIALS AND METHODS

A series of 17 adult idiopathic nephrotic patients with spontaneous cellulitis were retrospectively reviewed in Chang Gung Memorial Hospital, Kaohsiung from 1986 through 1996. We analyzed their physical conditions, clinical manifestations, and outcome. All patients received renal biopsies and had pathologic diagnoses.

RESULTS

The medical records of 17 patients were collected, 12 men and 5 women, with ages ranging from 16 to 63 years (mean 29.5 years). The pathologic diagnoses of renal biopsies included minimal change disease (13/17), membranous glomerulonephritis (2/17), mesangioproliferative glomerulonephritis (1/17) and focal/segmental glomerulosclerosis (1/17). All patients had generalized edematous state. The clinical presentations of these patients were variable. The mean serum albumin and daily urinary protein excretion were 1.28+/-0.64 g/dl and 8.75+/-5.16 g, respectively. The results of blood cultures were E. coli (3/17), Gram-negative bacilli (1/17), Streptococcus viridans (1/17), Streptococcus pneumoniae (1/17) and no growth (11/17). All patients responded to antibiotic treatment except one patient who died due to overwhelming sepsis.

CONCLUSION

The related factors of spontaneous cellulitis in patients with nephrotic syndrome are edematous skin, hypoalbuminemia, immunosuppressive drugs and defective immunity. Our patients had accordant conditions. The prognosis was good if diagnosis and treatment are made early.

Real-time frequency domain temperature and oxygen sensor with a single optical fiber

The combined excited-state phosphorescence life-times of an alexandrite crystal and platinum tetraphenylporphyrin Pt(TPP) in a single-fiber sensor are used to monitor temperature and oxygen concentration in the physiological range from 15-45 degrees C and 0-50% O2 with precision of 0.24 degree C and 0.15% O2 and accuracy of 0.28 degree C and 0.2% O2. A 500-micron cubic alexandrite crystal bound to the distal end of a 750-micron-diameter optical fiber core and the Pt(TPP) coated circumferentially with a length of 1 cm from the end of the same fiber are excited with pulsed super-bright blue LED light. This apparatus uses a 125-kHz sampler for data acquisition and frequency domain methods for signal processing. The instrument amplifies both the dc and ac components of the photomultiplier output and band limits the signal to 20 kHz. The fundamental frequency of the excitation is set to 488.3 Hz and the highest harmonic used is the 35th. This bandlimited signal is sampled and averaged over a few hundred cycles in the time domain. The frequency domain representation of the data is obtained by employing fast Fourier transform algorithms. The phase delay and the modulation ratio of each sampled harmonic are then computed. At least four log-spaced harmonic phases or modulations are averaged before decoding the two lifetimes of temperature and oxygen phosphorescent sensors. A component of zero lifetime is introduced to account for the excitation backscatter leakage through optical interference filters seen by the photodetector. Linear and second-order empirical polynomials are employed to compute the temperatures and oxygen concentrations from the inverse lifetimes. In the situation of constant oxygen concentration, the lifetime of Pt(TPP) changes with temperature but can be compensated using the measured temperature lifetime. The system drift is 0.24 degree C for the temperature measurement and 0.59% for the oxygen concentration measurement over 30 h of continuous operation. The instrumentation and methods allow for 6-s update times and 90-s full-response times.

[Clinical experience of automated double filtration plasmapheresis]

Double filtration plasmapheresis, one kind of fractionation plasmapheresis, was developed from membrane type plasmapheresis to remove only the pathogen and return the normal protein back to the patient. We started our automated double filtration plasmapheresis since December 1993. There were 13 patients who received one hundred treatments totally during one year period. And they are myasthenia gravis (8 patients); acute inflammatory demyelinating polyneuropathy (1 patient), multiple myeloma (1 patient); acquired factor VIII inhibitor (1 patient); autoimmune hemolytic anemia (1 patient); systemic lupus erythematous (1 patient). Technically double filtration plasmapheresis is easy to perform and time-saving. It also makes necessity of replacement fluid less frequent. Incidence of complication is rare, and this includes hypotension 2%, palpitation 1%, headache 1%, hemolysis 4%, air emboli 1%, high secondary pressure 2%, and no motality during our treatment. Clinical response is documented in cases of myasthenia gravis; acute inflammatory demyelinating polyneuropathy and acquired factor VIII inhibitor in our study. In conclusion, double filtration plasmapheresis is a time-saving, convenient, and safe therapeutic modality with rare complication. Because its effectiveness on limited kinds of diseases and costs relatively high price, thus plasmapheresis should be used in selected cases and treat aggressively if indicated.

Tetrodotoxin poisoning in Taiwan: an analysis of poison center data

Tetrodotoxin (TTX) poisonings are not infrequently seen in Taiwan, and several outbreaks have been recorded by the Poison Control Center (PCC)-Taiwan during 1988-1995. However, their demographic data, clinical features, and medical outcome have not been reported. A retrospective study analyzed the PCC data of TTX poisonings. All patients reported to the PCC-Taiwan as TTX poisoning from July 1988 through December 1995 were included. Excluding 2 incidents, the diagnosis of TTX poisoning was documented by identification of puffer fish and/or by the analysis of TTX in it. Patient age, sex, season of poisoning, substances ingested, incubation period, presenting symptoms, recovery time, and clinical outcome were analyzed. A total of 20 incidents involved 52 patients. Males outnumbered females (52% vs 41%) with sex undetermined in 4 patients. Most incidents occurred in the spawning seasons of puffer fish, eg March to May. Puffer fish ingestion accounted for 18 incidents; ingestion of gastropod mollusks and Gobius criniger were responsible for the other 2 incidents. Following ingestion of puffer fish and other poisonous marine animals, most symptoms developed within 6 h with complete recovery usually in 24 h. Symptoms of TTX poisoning were similar as those previously reported; however, unusual features, such as hypertension (24%), pinpoint pupils (4%), bronchorrhea and facial flush (2%), were also seen. The mortality rate was 13.5%. The violent neurotoxin is present in puffer fish and occurs in other marine animals. Without adequate therapy, patients may have serious morbidity or even succumb. Careful identification of puffer fish and other poisonous marine animals, as well as proper treatment of TTX poisoning patients, are mandatory to successfully handle cases of TTX poisoning.

Sequencing analysis of cDNA clones encoding the American cockroach Cr-PI allergens. Homology with insect hemolymph proteins

A previous article described the isolation of several lambdagt22A cDNA clones expressing the American cockroach (Periplaneta americana) Cr-PI allergens recognized by both human atopic IgE antibodies and anti-Cr-PI monoclonal antibodies (Wu, C. H., Lee, M. F., and Liao, S. C.(1995) J. Allergy Clin. Immunol. 96, 352-359). This article presents the nucleotide and deduced amino acid sequences of two cDNA clones encoding major allergens of P. americana. Clones C12 and C20 encode proteins of 685 and 631 amino acids with two potential N-glycosylation sites each. The predicted molecular weights for C12 and C20 cloned proteins are 79,300 and 75, 500 with isoelectric point values of 6.26 and 6.63, which are compatible with the determined sizes (Mr 78,000 and 72,000) and isoelectric point value (6.2) of the Cr-PI allergens of P. americana. A high degree of identity (69.1%), including several overlapped predicted central antigenic determinant residues, was found between two allergens. The anti-fusion protein antibody-based enzyme-linked immunosorbent assay was able to detect crude American cockroach extract, Cr-PI, recombinant proteins, and commercial cockroach extracts, which provides further evidence that two allergens share common antigen determinants. Recombinant allergens of clones C12 and C20 both showed 47.4% skin reactivities on 19 cockroach-sensitive asthmatic patients. Unexpectedly, although no sequence similarity was found to other known allergens, two aromatic amino acid-rich allergens were found to have a striking sequence identity to insect storage proteins (20.1-33.9%), insect juvenile hormone-suppressible proteins (30.9-36.4%), and arthropod hemocyanins (29.7-34.6%). Results suggested that two prominent allergens of P. americana are ancestrally related to these insect hemolymph proteins and represent a new group of proteins in the hemocyanin superfamily. These data will now facilitate epitope-mapping studies, and the recombinant allergens may be valuable for diagnostic and therapeutic purposes.

Real time frequency domain fibreoptic temperature sensor using ruby crystals

The excited state phosphorescence lifetime of ruby crystals is used to monitor temperature in the physiological range from 15 degrees to 45 degrees C with precision and accuracy less than 1 degree C, in real time. Precision of 0.1 degree C is attained with 3 min integration times. A 500 micron cubic ruby crystal bounded to the distal end of an optical fibre of similar core dimensions is excited with pulsed Ne-He laser light of about 9 microW average power. The instrument uses a sampler for data acquisition, and frequency domain methods for data fitting. The instrument amplifies the a.c. components of the detector output and band limits the signal to 800 Hz. The fundamental frequency of the excitation is set to 24.41 Hz to obtain 32 or less harmonics. This band-limited signal is sampled and averaged between 20 and 100 cycles to obtain temperature measurements in real time. The frequency domain representation of the data is obtained by employing fast Fourier transform algorithms. The phase delay and the modulation ratio, of each sampled harmonic, is then computed. Five to 32 values of the phase and modulation are averaged before computing the sensor lifetime. The technique is capable of measuring precise and accurate excited state lifetimes from subpicowatt luminescent signals in plastic optical fibres. A least squares fit yields the lifetimes of single exponentials. A component of zero lifetime is introduced to account for the backscatter excitation seen by the photodetector leaking through optical interference filters. The phosphorescence lifetimes measured reproducibly to about six parts in 1000, with a 2 s integration time, are used to monitor physiological temperature. Temperatures are computed employing empirical polynomials. The system drift is 3% over 5 h of continuous operation. The instrumentation and methods allow 2.7 s update times and 50 s full response times.

Evaluating lead bioavailability data by means of a physiologically based lead kinetic model

A method of bioavailability estimation is presented in which a physiologically based kinetic model of lead kinetics is fit simultaneously to blood and bone lead concentrations after a period of exposure to dietary lead. Optimization of the simultaneous fit, varying only fractional absorption, gives the best estimate of fractional bioavailability for each treatment group. The analysis was applied to data from three separate studies in which rats were fed for 30 consecutive days purified diets containing lead added as lead acetate, mine waste-contaminated test soils, or mine waste itself. Fractional absorption decreased as lead intake increased, regardless of the source of the lead; but the magnitude of this dose dependence was lead source-dependent. There were no differences in lead absorption by male and female rats when lead intake was expressed per unit body weight. Fractional absorption varied from 4 to 5%, at low exposure rates (1-2 mg lead/kg/day) when lead acetate was added to the diet, to 0.24% at a high exposure rate (24 mg/kg/day) when a mine waste-contaminated test soil was added to the diet. Comparison of the results of this analysis with the results of a more conventional analysis, in which the bone and blood lead concentrations were separately compared with bone and blood lead concentrations in rats given daily injections of lead acetate intravenously for 29 consecutive days, demonstrated that the standard analysis failed to reveal the dose dependence of fractional absorption.

Bioavailability of arsenic in soil and house dust impacted by smelter activities following oral administration in cynomolgus monkeys

This study was conducted to determine the extent of arsenic (As) absorption from soil and house dust impacted by smelter activities near Anaconda, Montana. Female cynomolgus monkeys were given a single oral administration via gelatin capsules of soil (0.62 mg As/kg body wt) or house dust (0.26 mg As/kg body wt), or soluble sodium arsenate by the gavage or intravenous route of administration (0.62 mg As/kg body wt) in a crossover design with a minimum washout period of 14 days. Urine, feces, and cage rinse were collected at 24-hr intervals for 168 hr. Blood was collected at specified time points and area under the curves (AUCs) was determined. Arsenic concentrations for the first 120 hr, representing elimination of greater than 94% of the total administered dose for the three oral treatment groups, were < 0.021 to 4.68 micrograms/ml for the urine and < 0.24 to 31.1 micrograms/g for the feces. In general, peak concentrations of As in the urine and feces were obtained during the collection intervals of 0-24 and 24-72 hr, respectively. The main pathway for excretion of As for the intravenous and gavage groups was in the urine, whereas for the soil and dust groups, it was in the feces. Mean absolute percentage bioavailability values based on urinary excretion data were 68, 19, and 14% for the gavage, house dust, and soil treatments, respectively, after normalization of the intravenous As recovery data to 100%. Corresponding absolute bioavailability values based on blood were 91, 10, and 11%. The bioavailability of soil and house dust As relative to soluble As (by gavage) was between 10 and 30%, depending upon whether urinary or blood values were used. These findings suggest that risks associated with the ingestion of As in soil or dust will be reduced compared to ingestion of comparable quantities of As in drinking water.

Light transmittance as an index of cell volume in hippocampal slices: optical differences of interfaced and submerged positions

Light transmittance (T) in the CA1 region of hippocampal slices was measured during exposure to media of various osmolarities to determine the utility of optical measurements as an index of changes in cell volume. In slices positioned at the gas-liquid interface, hypo-osmotic medium consistently produced a decrease in T and hyperosmotic medium produced an increase in T. The magnitude of deltaT was graded as a function of the strength of osmotic change. All changes in T were reversible upon return to isosmotic medium. In contrast, osmotically induced changes in T in submerged slices were consistently opposite in direction to those observed in slices at the interface. The magnitude and direction of deltaT could be altered by systematic variation of the level of the bathing medium within the same chamber, indicating that both extrinsic optical properties of various interfaces, such as refraction and reflection, and intrinsic optical properties of the tissue contribute to the observed T. Spectral measurements eliminated the possibility that osmotically induced deltaT was the result of changes in light absorbance by intrinsic chromophores such as cytochromes or hemoglobin. The results show that measurements of deltaT can be a useful index of changes in cell volume in brain slices, provided that the level of the bath remains constant.

Isolation and preliminary characterization of cDNA encoding American cockroach allergens

BACKGROUND

Two prominent proteins of 78 and 72 kd in Cr-PI have been found to be the major allergens of American cockroach (Periplaneta americana).

METHODS

A lambda gt22A cDNA library generated from messenger RNA of American cockroach was packaged into Escherichia coli Y1090(r-) and initially screened with rabbit polyclonal antiserum raised to crude extract of American cockroach (CRa-A).

RESULTS

Twenty-nine anti-CRa-A-positive clones were isolated, and 11 clones were recognized by rabbit anti-Cr-PI and reactive with IgE antibodies of atopic serum pool. Among these 11 clones, eight were recognized by murine anti-Cr-PI monoclonal antibodies. Four clones (C7, C8, C12, and C29) were found to contain inserts of 2.6 kilobases (kb), and clones C5 and C20 were found to contain inserts of 2.4 kb. The remaining clones (C13, C23, C25, C28, and C35) were found to contain inserts of 1.8, 1.6, 2.5, 1.7, and 0.9 kb, respectively. Clones C12, C20, C13, and C28 were selected, subcloned into the expression pET vectors, and used to transform, E. coli BL21(DE3). Immunoblot analyses of clones C12, C20, C13, and C28 with anti-Cr-PI monoclonal antibodies revealed fusion proteins with molecular weights of 78 and 50 kd, and 43 kd, 54 kd, and 46 kd, respectively. However, among those fusion proteins only those with molecular weights of 78, 72, 54, and 46 kd were able to bind human specific IgE antibodies.

CONCLUSIONS

The cDNA clones are expected to code for the major and principal allergens of American cockroach, and recombinant allergens may therefore be valuable for diagnostic and therapeutic purposes.

Fabry's disease: clinical, pathologic and biochemical manifestations in two Chinese males

Fabry's disease is a rare hereditary disease transmitted as an X-linked recessive trait with the primary metabolic defect of an enzyme alpha-galactosidase A, resulting in deposition of glycolipids (ceramide trihexoside) in various tissues, including the kidneys. Two sibling cases of Chinese adult male patients in a family with Fabry's disease were completely evaluated including the clinical, pathologic and biochemical studies. Both of the patients had the similar clinical manifestations such as telangiectases, proteinuria, acral pains, corneal opacities, tortuous renal vessels and recurrent fever. Chronic renal insufficiency was noted in Case 1, whereas Case 2 had normal renal function. Microscopic hematuria was noted in Case 1. In renal biopsy, LM showed foamy vacuolation of the glomerular visceral epithelial cells and EM showed widespread myelin bodies (Zebra bodies) in kidney tissues, most numerous in visceral epithelia in both cases. Those findings are diagnostic for Fabry's disease. The plasma activity of alpha-galactosidase of Case 1 was 0.8 and that of Case 2 was 1.0 (normal reference range: 8.5-18.5 nmol/hr/min). The plasma activity of alpha-galactosidase A of Case 1 was 0.4 and that of Case 2 was 0.8 (normal reference range: 7.9-16.9 nmol/hr/min). All the enzyme activities in both cases were much lower than those of normal subjects. In addition to clinical presentations, pathologic study and biochemical study with assays of plasma or serum activities of alpha-galactosidase and alpha-galactosidase A are important steps in the diagnosis of Fabry's disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Absolute bioavailability of lead acetate and mining waste lead in rats

The primary purpose of this study was to generate data that could be used to determine the absolute bioavailability of lead using data from a previous study in which soil containing lead from mining waste was mixed with feed. Young male and female Sprague-Dawley rats (7-8 weeks of age, five/sex/group) were given either soluble lead acetate mixed in a purified diet (AIN-76) at three different dose levels (1, 25, and 250 ppm Pb for 30 consecutive days) or intravenously at doses of 0.02, 0.20, and 2.0 mg Pb/kg BW for 29 days. A control group (purified diet only) was also included. The intravenous groups were used to provide maximal absorption (lead presumed to be 100% bioavailable) and accumulation data for lead in blood, bone, and liver. The lead acetate groups were used to evaluate the comparability of the present study with a previous study that compared bioavailable lead from ingested soil and lead acetate. Group mean whole blood, bone and liver lead concentration values increased with increasing dose levels for all treatment groups. A linear relationship was observed between blood lead concentration and dose following intravenous administration of lead and this provided empirical support for using blood lead concentrations at supposed steady state (approximately 30 days) to compute the bioavailability of lead administered by different routes and from different sources. The absolute bioavailability values of mining waste lead in soil were low based on the results for all tissue types. Absolute bioavailability values for lead acetate in dosed feed for blood, bone, and liver were approximately 6-, 19-, and 20-fold greater, respectively, than mining waste lead. Based on the current design and test system used, the absolute bioavailability of mining waste lead in soil administered in feed was approximately 3% based on blood data and less than 1% based on bone and liver data. These data are consistent with the low solubility of the constituent lead mineral phases in Butte soils.

Bioavailability of arsenic in soil impacted by smelter activities following oral administration in rabbits

This study determined the extent of arsenic (As) absorption from soil from Anaconda, Montana. Prepubescent male and female SPF New Zealand White rabbits (5/sex/group) were given a single oral (capsule) administration of soil (3900 ppm As) at three different dose levels (0.2, 0.5, and 1.0 g of soil/kg, corresponding to 0.78, 1.95, and 3.9 mg As/kg, respectively). Standard groups included untreated controls, an intravenous sodium arsenate group (1.95 mg As/kg), and a gavage sodium arsenate group (1.95 mg As/kg). Urine, cage rinse, and feces were collected at 24-hr intervals for 5 days and were analyzed for total As concentration. Clinical signs, body weights, and food consumption for treated animals were similar to controls. Maximum As concentrations were obtained over the initial 24-hr collection interval. A dose-dependent delay in urinary As excretion, the major elimination pathway, was observed in the oral soil group compared to that in the gavage group. For the animals in the soil groups, approximately 80% of the administered As dose was eliminated in the feces compared to approximately 10 and 50% for the intravenous and oral gavage groups, respectively. The relative oral bioavailabilities (+/- SD) of As in the gavage and test soil groups based on comparison with excreta data from the intravenous group were approximately 50 +/- 5.7 and 24 +/- 3.2%, respectively (after normalization of intravenous group's As recovery data to 100%). These results indicated that As in the soil was probably in a less soluble and therefore a less absorbable form than sodium arsenate.