Acute Hypoxia Activates an ENaC-like Channel in Rat Pheochromocytoma (PC12) Cells

Cells can resist and even recover from stress induced by acute hypoxia, whereas chronic hypoxia often leads to irreversible damage and eventually death. Although little is known about the response(s) to acute hypoxia in neuronal cells, alterations in ion channel activity could be preferential. This study aimed to elucidate which channel type is involved in the response to acute hypoxia in rat pheochromocytomal (PC12) cells as a neuronal cell model. Using perfusing solution saturated with 95% N₂ and 5% CO₂, induction of cell hypoxia was confirmed based on increased intracellular Ca²⁺ with diminished oxygen content in the perfusate. During acute hypoxia, one channel type with a conductance of about 30 pS (2.5 pA at -80 mV) was activated within the first 2~3 min following onset of hypoxia and was long-lived for more than 300 ms with high open probability (P_o, up to 0.8). This channel was permeable to Na⁺ ions, but not to K⁺, Ca⁺, and Cl^- ions, and was sensitively blocked by amiloride (200 nM). These characteristics and behaviors were quite similar to those of epithelial sodium channel (ENaC). RT-PCR and Western blot analyses confirmed that ENaC channel was endogenously expressed in PC12 cells. Taken together, a 30-pS ENaC-like channel was activated in response to acute hypoxia in PC12 cells. This is the first evidence of an acute hypoxia-activated Na⁺ channel that can contribute to depolarization of the cell.     

院前急救对急性出血性脑卒中患者的影响

目的:分析和探讨院前急救对急性出血性脑卒中患者预后及死亡率的影响。方法:选取急诊科150例急性出血性脑卒中患者,其中107例经院前急救给予心电监护、吸氧、镇静、脱水降颅压等初步处理后送往石景山医院急诊科就诊,43例自行来院(未经任何处理,由家属直接送入医院)。对两组患者进行分析比较。结果:107例患者经过院前急救,预后良好率37.4%,植物生存率9.3%,死亡率5.6%;而其余43例患者预后良好率11.6%,植物生存率32.6%,死亡率23.2%。院前急救在争取院内救治时间、降低病死率和神经系统并发症等方面均具有显著的作用和效果。结论:及时有效的院前救治大大降低了急性出血性脑卒中的植物生存率和病死率,对于进一步提高抢救成功率和预后生存质量起到了至关重要的作用。     

Torsemide Versus Furosemide After Continuous Renal Replacement Therapy Due to Acute Renal Failure in Cardiac Surgery Patients

Acute renal failure (ARF) usually develops in 5% to 30% of patients undergoing heart surgery and is associated with a more complicated clinical evolution course and with an excessive mortality of up to 80%. The objective of this study was to verify the frequency of ARF in postoperative coronary artery bypass surgery with and without cardiopulmonary bypass, by the evaluation of renal function markers' performance [ plasma creatinine, plasma urea, urinalysis, fractional excretion of sodium, creatinine clearance and Alpha‐glutathione S‐transferase (α‐GST)], besides to verify possible relations between clinical variables involved in postoperative heart surgery and the occurrence of renal insufficiency.     

新昌地区0～5岁儿童急性下呼吸道感染的病原菌及耐药性分析

目的 调查分析新昌地区0～5岁儿童急性下呼吸道感染的病原菌分布及耐药性,为临床抗菌药物使用提供依据.方法 对新昌地区2009年1月-2010年12月0～5岁住院儿童符合急性下呼吸道感染876例患儿进行痰液分离培养,做菌株鉴定和药敏试验.结果 共分离出病原菌303株,其中革兰阳性菌占49.2％,革兰阴性菌占40.2％,真菌占10.6％；革兰阳性菌中以肺炎链球菌和金黄色葡萄球菌为主,对青霉素耐药率均＞75.7％,肺炎链球菌对红霉素耐药率为90.5％；革兰阴性菌以大肠埃希菌、肺炎克雷伯菌及阴沟肠杆菌为主,对氨苄西林、哌拉西林耐药率＞80.0％,而β-内酰胺酶抑制剂复合剂则抗菌活性较好,敏感的抗菌药物为亚胺培南、氟喹诺酮类、氨基糖苷类.结论 由于儿科抗菌药物的广泛使用,使常见病原菌对抗菌药物的耐药性日趋严重,应加强对病原菌及耐药性的监测,促进抗菌药物的合理使用.     

Health and Ecological Effects of Adiponitrile

Adiponitrile (ADN) has moderate acute toxicity with an oral LD₅₀ in rats of 100 to 500 mg/kg and a 4‐hr LC₅₀ in rats of 1.71 mg/L (vapor plus aerosol). ADN produced slight eye but no skin irritation in rabbits. Repeated exposures by inhalation produced changes in the hematologic profile with effects seen at 100 or 300 mg/m³. The hematologic changes were reversible upon cessation of further inhalation exposures. Dogs fed up to 500 ppm (equivalent to 12–15 mg/kg) showed no effects but 1,000 ppm produced vomiting and nausea which limited further testing at that concentration. ADN was not a genetic toxin, developmental toxin, reproductive toxin nor did it produce an increase in tumors in a 2‐yr drinking water study in rats. Human experience reports are limited to one accidental poisoning case and a few skin exposures resulting in transient irritation and inflammation. ADN is rapidly absorbed and excreted by mammals, and is metabolized to some extent although unchanged ADN is readily detected in urine, and does not bioaccumulate.     

The acute effects of waterpipe smoking on lung function and exercise capacity in a pilot study of healthy participants

Abstract

Context: Waterpipe tobacco smoking (WTS) has gained popularity, but its physiologic effects have not been extensively studied: rather, studies have focused on WTS’s chronic effects or have evaluated limited respiratory/cardiac parameters.

Objective: We sought to characterize in a more detailed manner the acute effects of WTS on lung function and exercise capacity.

Method: We recruited 24 healthy WTS males. We used a pilot single-group pre-test (abstained from WTS for ≥48?h) post-test (within 0.5?h of a 45-min WTS session) design. We performed spirometry, diffusing lung capacity and time-limited CPE testing (CPET; cycloergometer; 2-min 20-Watt warm-up and 25-Watt increase every 2-min for 10?min).

Results: Mean age was 20.4 years; Post-WTS, the following significant changes were observed: CO level increased from 3.7?ppm to 24.4; oxygen consumption decreased (from 1.86?L/min to 1.7); baseline respiratory rate increased (from 17.7 breath/min to 19.7); forced expiratory flow over the middle half of the forced vital capacity decreased (from 5.51?L to 5.29); and perceived exertion (measured by Borg scale) at mid and peak exercise increased. Baseline resting systolic blood pressure, pulse pressure, and pulse pressure product increased post-WTS (from 118.9?mmHg to 129.2; from 45.3?mmHg to 55.6; and from 9.9?mmHg/min to 11.1 post-WTS, respectively). During exercise, a decrease in oxygen pulse was observed post-WTS (from 10.89?ml/beat to 9.97), while the heart rate-oxygen consumption relationship increased post-WTS (from 3.52 beats/ml/kg to 3.91).

Conclusion: Acute WTS appears to induce impairment in lung function and exercise capacity. Larger studies are warranted to further characterize the nature and extent of such impairment.     

Influence of cognition and symptoms of schizophrenia on IADL performance

Abstract

People with schizophrenia experience difficulties with instrumental activities of daily living (IADL), which are required for independent living. Yet, factors that influence IADL performance are still poorly understood. Identification of such factors will contribute to the rehabilitation process and recovery. The present study aimed to examine the influence of cognitive abilities, schizophrenia symptoms, and demographic variables on IADL functioning during acute hospital admission. The participants were 81 adults with DSM-IV chronic schizophrenia. They were assessed on the Revised Observed Tasks of Daily Living (OTDL-R), the Positive and Negative Syndrome Scale (PANSS), the Neurobehavioral Cognitive Status Examination (Cognistat), and the Kitchen Task Assessment (KTA) at acute hospitalization. The prediction model of IADL performance at this time consists of executive functioning (explained 21% of variance), memory and abstract thinking (explained 13.5%), negative symptoms (explained 13%), age of illness onset and years of education (explained 8%). The total explained variance is 53.5%. These results provide evidence-based guidelines for the evaluation process in inpatient settings. Such guidelines are important since planning of intervention processes and appropriate community integration programs often occurs during acute hospitalization, while the structured nature of inpatient settings limits natural variability in occupational performance.     

Atypical respiratory complications of dengue fever

In last decade, dengue has emerged as one of the most important vector born disease. With increasing cases, uncommon presentations and complications are now commonly recognized. Here, we report two cases of rare pattern of respiratory involvement in dengue: acute respiratory distress syndrome and bronchiolitis with respiratory failure.