Impact of intraoperative hypotension and blood pressure fluctuations on early postoperative delirium after non-cardiac surgery.

INTRODUCTION: Postoperative delirium is common in older patients. Despite its prognostic significance, the pathophysiology is incompletely understood. Although many risk factors have been identified, no reversible factors, particularly ones potentially modifiable by anaesthetic management, have been identified. The goal of this prospective cohort study was to investigate whether intraoperative hypotension was associated with postoperative delirium in older patients undergoing major non-cardiac surgery. METHODS: Study subjects were patients >65 years of age, undergoing major non-cardiac surgery, who were enrolled in an ongoing prospective observational study of the pathophysiology of postoperative delirium. Intraoperative blood pressure was measured and predefined criteria were used to define hypotension. Delirium was measured by the Confusion Assessment Method on the first two postoperative days. Data were analysed using t-tests, two-sample proportion tests and ordered logistic regression multivariable models, including correction for multiple comparisons. RESULTS: Data from 594 patients with a mean age of 73.6 years (sd 6.2) were studied. Of these 178 (30%) developed delirium on day 1 and 176 (30%) on day 2. Patients developing delirium were older, more often female, had lower preoperative cognitive scores, and underwent longer operations. Relative hypotension (decreases by 20, 30, or 40%) or absolute hypotension [mean arterial pressure (MAP)<50 mm Hg] were not significantly associated with postoperative delirium, nor was the duration of hypotension (MAP<50 mm Hg). Conversely, intraoperative blood pressure variance was significantly associated with postoperative delirium. DISCUSSION: These results showed that increased blood pressure fluctuation, not absolute or relative hypotension, was predictive of postoperative delirium.

Acute aortic dissection: perspectives from the International Registry of Acute Aortic Dissection (IRAD).

Acute aortic dissection is a rare but deadly disease first described over 200 years ago by the physician to the late King George II on necropsy. Over the ensuing 2 centuries, the understanding of the pathophysiology, presentation, diagnosis, treatment and follow-up has matured. In an effort to understand the contemporary treatment of this disease, the International Registry of Acute Aortic Dissection (IRAD) has enrolled over 2000 patients over the past 12 years. In this article we summarize the key lessons learned from this multi-national registry of patients presenting with acute aortic dissection.

Application of surfactant enhanced permanganate oxidation and bidegradation of trichloroethylene in groundwater.

The industrial solvent trichloroethylene (TCE) is among the most ubiquitous chlorinated solvents found in groundwater contamination. The main objectives of this study were to evaluate the feasibility of using non-ionic surfactant Simple Green (SG) to enhance the oxidative dechlorination of TCE by potassium permanganate (KMnO4) employing a continuous stir batch reactor system (CSBR) and column experiments. The effect of using surfactant SG to enhance the biodegradation of TCE via aerobic cometabolism was also examined. Results from CSBR experiments revealed that combination of KMnO4 with surfactant SG significantly enhanced contaminant removal, particularly when the surfactant SG concentrated at its CMC. TCE degradation rates ranged from 74.1% to 85.7% without addition of surfactant SG while TCE degradation rates increased to ranging from 83.8% to 96.3% with presence of 0.1wt% SG. Furthermore, results from column experiments showed that TCE was degraded from 38.1microM to 6.2microM in equivalent to 83.7% of TCE oxidation during first 560min reaction. This study has also demonstrated that the addition of surfactant SG is a feasible method to enhance bioremediation efficiency for TCE contaminated groundwater. The complete TCE degradation was detected after 75 days of incubation with both 0.01 and 0.1wt% of surfactant SG addition. Results revealed that surfactant enhanced chemical oxidation and bioremediation technology is one of feasible approaches to clean up TCE contaminated groundwater.

Presence of serum anti-p53 antibodies is associated with pleural effusion and poor prognosis in lung cancer patients.

This study was designed prospectively to evaluate the development of anti-p53 antibodies (Abs) in lung cancer patients in relation to their clinical outcome. Sera, derived from 125 lung cancer patients, consisting of 14 small cell lung cancers (SCLC) and 111 non-SCLCs (NSCLC), were surveyed. The p53-null human NSCLC cell line, NCI-H1299, transfected with a human mutant p53 gene was prepared as the source of p53 antigen for immunoblotting analyses to detect the presence of serum anti-p53 Abs. The control group included sera from 10 healthy adults and 14 patients with benign pulmonary diseases. Clinical data including staging and survival were recorded for statistical analyses. The anti-p53 Abs were found in 8% (10 of 125) of the lung cancer patients studied (8.1% of NSCLC versus 7.1% of SCLC patients), whereas none of the control sera had detectable anti-p53 Abs. The presence of anti-p53 Abs was closely associated with malignant pleural effusions (P = 0.001). The p53 Ab-positive patients had a worse prognosis than the p53 Ab-negative patients (P < 0.02; median survival, 20 versus 41 weeks). In both univariate and multivariate analyses, the tumor extension and probably the presence of anti-p53 Abs were significant predictors for cancer death. The development of anti-p53 Abs (n = 9) was also a predictor for poor survival in patients with malignant effusions (n = 51). In conclusion, the presence of serum anti-p53 Abs is closely associated with malignant pleural effusions in lung cancer patients. It may serve as a negative prognostic factor for survival independent of malignant pleural effusions and tumor staging.

Quality improvement initiative and its impact on the management of patients with acute myocardial infarction.

BACKGROUND: Wide variation exists in acute myocardial infarction (AMI) management, leading to differences in outcomes. OBJECTIVE: To assess the impact of the quality improvement initiative on appropriate management of AMI. DESIGN: Prospective patient identification, retrospective medical record review. PATIENTS: All patients with AMI discharged alive (N = 497) from our institution between April 1, 1995, and February 28, 1997. MAIN OUTCOME MEASURE: The effect of quality improvements directed at the patient, nurse, and physician on the adherence to key quality indicators. RESULTS: The quality improvement initiative correlated with more frequent use of reperfusion therapy (98%), and with aspirin use in the emergency department (95%), in ideal eligible patients. Similarly, adherence to discharge quality indicators, including use of aspirin (97%), beta-blockers (94%), angiotensin-converting enzyme inhibitors (90%), and lipid-lowering agents (67%); avoidance of calcium channel blockers (93%); a low-fat diet (96%); smoking cessation counseling (94%); and outpatient rehabilitation referral (70%) was higher, including in the very old (those aged >/=80 years) and in women. The use of a patient education tool was associated with a higher adherence to most quality indicators compared with patients in whom this was not used: discharge aspirin (99% vs 96%; P =.02), beta-blocker (98% vs 91%; P =.002), angiotensin-converting enzyme inhibitor (95% vs 86%; P =.01), and lipid-lowering agent (71% vs 62%; P =.04) use; outpatient rehabilitation (82% vs 63%; P=.001); and documentation of smoking cessation counseling (98% vs 87%; P =. 001). CONCLUSIONS: Implementation of a quality improvement program was associated with a high adherence to quality-of-care indicators for AMI. Patient-directed feedback before discharge improved adherence to key indicators for AMI beyond that achieved with tools only directed at caregivers.

Visual attention in Huntington's disease: the effect of cueing on saccade latencies and manual reaction times.

Studies of eye movements in patients with Huntington's disease (HD) have suggested that frontal lobe-basal ganglia structures are more involved in HD than the parietal lobes. To test this hypothesis further we compared the ability of HD patients and normal subjects to direct "covert" visual attention, using saccade latency and thumb press reaction time tasks that have been shown to be sensitive to parietal lobe dysfunction. Subjects were instructed to move their eyes or to press a button when a peripheral target was illuminated. The peripheral stimulus appeared at various intervals after the appearance of a central arrow(s) that pointed in the direction of the target (valid cue), in the opposite direction (invalid cue), or pointed simultaneously in both directions (neutral cue). For both saccade and thumb press paradigms, the difference in the latencies for trials with invalid and valid cues was the same in HD patients and normals. These findings suggest that the ability to direct visual attention is normal in HD and are compatible with the hypothesis that in HD, frontal-basal-ganglia circuits are more affected than parietal lobe pathways.

Effect of cryopreservation on the presence of endothelial cells on human valve allografts.

Cryopreserved human allograft valves are useful in a variety of cardiac operations. The presence or absence of endothelial cells on allografts may be important in determining immunogenicity and ultimate graft longevity. The purpose of this study was to determine whether endothelial cells are present on cryopreserved human allografts. Portions of cryopreserved allografts (35 valve leaflets, 96 pieces of arterial wall) not used at operation were studied. For comparison, untreated tissues (44 valve leaflets, 46 pieces of arterial wall) were obtained from structurally normal hearts and lungs removed or inserted at the time of transplantation and from pathologic tissues obtained during operations for congenital heart defects. A monolayer of cells from the luminal surface of each specimen was harvested by means of a Hautchen preparation. The monolayer was stained with fluorescein isothiocyanate-labeled Ulex europaeus I, a lectin with strong affinity for human endothelium. Positive staining with fluorescein was considered to be evidence for the presence of human endothelium. Endothelial cells were observed on 21 of 131 (16%) cryopreserved allograft specimens and on 70 of 90 (78%) untreated tissues (p < 0.001). These results show that cryopreservation typically results in the loss of endothelium from aortic and pulmonary valve allografts. These findings may have important implications for the immunologic response of the host to allograft implantation.

Foreign body aspiration into the lower airway in Chinese adults.

OBJECTIVES: Foreign body aspiration into the lower airway in adults is uncommon. We designed this study to investigate the clinical presentations, precipitating factors, management choice, and complications of foreign body aspiration in Chinese adults. PATIENTS AND METHODS: We analyzed 43 consecutive adult patients with foreign body aspiration between February 1980 and December 1995 from the medical record registry and cross index system of a tertiary medical center. RESULTS: The most common symptoms are chronic cough, hemoptsis, fever, and dyspnea. Only three patients (7%) presented with choking. Chest radiograph demonstrated the foreign body in nine cases (21%). The most common foreign body was bone fragments (21/43, 49%). Lodgment is more common in the right, especially the right intermediate bronchus and basal bronchus. Three patients were also diagnosed as having lung cancers. Precipitating factors include CNS dysfunction, facial trauma, intubation, dental procedure, and underlying pulmonary diseases. Flexible fiberoptic bronchoscopy removed the foreign body in 25 cases (58%) during the first attempt and 32 cases (74%) in total. Complications include obstructive pneumonitis (including one case of actinomycosis infection), atelectasis, bronchiectasis, lung abscess, and lung torsion (two cases). CONCLUSION: The nature of foreign body in Chinese adults was different from the Western adults. The initial clues to foreign body aspiration in adults are usually obscure or indirect. We suggest flexible fiberoptic bronchoscopy as the first-line approach. Follow-up bronchoscopy and chest radiograph are recommended to detect chronic complications or coexisting lung cancer.

Effects of preservation techniques on in vivo expression of adhesion molecules by aortic valve allografts.

Methods of sterilization and preservation of aortic valve allografts influence graft longevity. The effect of storage techniques on valve durability may be mediated by alterations in the immunologic properties of the allograft, which are reflected by expression of leukocyte adhesion molecules. Rat aortic valve grafts were transplanted in the fresh state, after cryopreservation (-196 degrees C), or after storage at 4 degrees C for 1 to 21 days. Syngeneic and strongly allogeneic valves were transplanted for 4 hours to 21 days and were retrieved for immunohistochemical staining for expression of leukocyte adhesion molecules. Unimplanted valves and transplanted syngeneic valves, regardless of storage methods, exhibited little or no expression of leukocyte adhesion molecules. Fresh allogeneic valves expressed all molecules, indicating up-regulation, at all time intervals studied. Cryopreserved allogeneic valves demonstrated no leukocyte adhesion molecules at 4 hours or 2 days and weak reactivity at 10 and 21 days. Allogeneic valves stored at 4 degrees C, regardless of the duration of storage, demonstrated weak expression of all molecules at 10 days and strong expression at 21 days. Expression of leukocyte adhesion molecules requires an allogeneic environment and may precede immune-mediated injury. Reduced expression of leukocyte adhesion molecules resulting from storage may predict a diminished immunologic response. Cryopreservation (-196 degrees C) causes the greatest delay and diminution of expression of leukocyte adhesion molecules.

Endothelial cell replication in an in vivo model of aortic allografts.

Previous studies of aortic valve allograft viability have used in vitro assessments that may not reflect in vivo properties. This study evaluated in vivo endothelial cell replication in experimental valved aortic grafts and examined the consequences of histoincompatibility and cryopreservation. Valved aortic conduits were heterotopically transplanted into syngeneic or allogeneic rats. Tritiated thymidine was administered to graft recipients and control rats. After 72 hours, monolayers from the native aortas and the aortic portion of the grafts were prepared for autoradiography, with six or more silver grains per nucleus considered evidence of replication. Percentages of replicating cells in native aortas ranged from 0.3% to 2.3% (p = not significant). Percentages of replicating cells in the fresh isografts (12.4%) and allografts (12.2%) were not significantly different from each other, although each was significantly greater than the percentage in its native aorta (p < 0.04). Cryopreserved allografts and isografts displayed a few endothelial cells, none of which was replicating. Immunologic differences do not affect endothelial cell replication in this early period after fresh graft transplantation. Cryopreservation, however, results in the absence of replicating endothelium.

Analysis of volition latency on antisaccadic eye movements.

The antisaccadic paradigm can be applied to test the suppression of reflexive saccades and the activation of volitional saccades simultaneously. The impaired frontal cortex has been shown to have difficulty in suppressing reflexive saccade (prosaccade) to make a successful antisaccade. Degraded antisaccade performance can also be observed in patients with Parkinson's disease (PD). The studies of PD based on the prosaccadic and antisaccadic paradigms have shown controversial findings; the latency between patients and age-matched controls could be either with or without significant difference. Even with this inconsistency, our previous study and recent analysis have supported that the latency of both prosaccade and antisaccade increases significantly for patients with PD. The objective of this study is to investigate whether prolonged antisaccade latency is caused by the affected volitional decision process (volition latency) or simply by the delayed initiation of saccade with direction opposite to the cue, by measuring prosaccade and antisaccade latency from the intermingled paradigms. Eleven mildly affected patients with idiopathic PD and eight age-matched normal subjects were tested in this study. As compared to the age-matched control, the results showed that prosaccade, antisaccadic, and volition latency of the patients was significantly elevated (P<0.01). We conclude that antisaccade performance for the PD patients was degraded for both the volition decision process and the initiation of saccade with direction opposite to the cue. Also, volition latency analysis is a more objective method than prosaccade and antisaccade latency analysis, which can be compared among results obtained from different analysis methodologies.

Sarcoidosis among Chinese in Taiwan.

Sarcoidosis is a multisystem disorder of unknown causes, characterized by widespread noncaseating epithelioid cell granuloma in more than one organ. It is rare among Chinese people. In recent years, a rapidly increasing incidence among inpatients of the Veterans General Hospital-Taipei has been noted. We retrospectively reviewed the records at our hospital from January 1960 through December 1995. We found 38 cases of sarcoidosis with biopsy-proven involvement of at least one organ system, in addition to either a typical clinical manifestation or chest radiograph. The disease-specific rate per thousand admissions increased from 0.0025 in the 1960s to 0.004 in the 1980s: for 1990 to 1995, it jumped to 0.027. Two possible explanations for the increasing incidence are greater awareness and recognition of this disease among physicians and pathologists, and advances in invasive diagnostic techniques and histopathology. Compared with patients in Western countries, sarcoidosis among Chinese patients in Taiwan had the following characteristics: 1) a higher frequency of patients (97%) had intrathoracic involvement, 2) there was a low incidence of hypercalcemia and hyperglobulinemia, and 3) there was an inclination toward older age at presentation. In conclusion, the incidence of sarcoidosis among Chinese in Taiwan has increased in the past 3 decades. The clinical presentations of patients differed from those reported from Western countries.

Portable and programmable clinical EOG diagnostic system.

Monitoring eye movements is clinically important in diagnosis of diseases of the central nervous system. Electrooculography (EOG) is one method of obtaining such records which uses skin electrodes, and utilizes the anterior posterior polarization of the eye. A new EOG diagnostic system has been developed that utilizes two off-the-shelf portable notebook computers, one projector and simple electronic hardware. It can be operated under Windows 95, 98, NT, and has significant advantages over any other similar equipment, including programmability, portability, improved safety and low cost. Especially, portability of the instrument is extremely important for acutely ill or handicapped patients. The purpose of this paper is to introduce the techniques of computer animation, data acquisition, real time analysis of measured data, and database management to implement a portable, programmable and inexpensive contacting EOG instrument. It is very convenient to replace the present expensive, inflexible and large-sized commercially available EOG instruments. A lot of interesting stimulation patterns for clinical application can be created easily in different shape, time sequence, and colour by programming in Delphi language. With the help of Winstar (a software package that is used to control I/O and interrupt functions of the computer under Windows 95, 98, NT), the I/O communication between two notebook computers and A/D interface module can be effectively programmed. In addition, the new EOG diagnostic system is battery operated and it has the advantages of low noise as well as isolation from electricity. Two kinds of EOG tests, pursuit and saccade, were performed on 20 normal subjects with this new portable and programmable instrument. Based on the test result, the performance of the new instrument is superior to the other commercially available instruments. In conclusion, we hope that it will be more convenient for doctors and researchers to do the clinical EOG diagnosis and basic medical science research by using this new creation.

Application of polycolloid-releasing substrate to remediate trichloroethylene-contaminated groundwater: a pilot-scale study.

The objectives of this pilot-scale study were to (1) evaluate the effectiveness of bioremediation of trichloroethylene (TCE)-contaminated groundwater with the supplement of slow polycolloid-releasing substrate (SPRS) (contained vegetable oil, cane molasses, surfactants) under reductive dechlorinating conditions, (2) apply gene analyses to confirm the existence of TCE-dechlorinating genes, and (3) apply the real-time polymerase chain reaction (PCR) to evaluate the variations in TCE-dechlorinating bacteria (Dehalococcoides spp.). Approximately 350L of SPRS solution was supplied into an injection well (IW) and groundwater samples were collected and analyzed from IW and monitor wells periodically. Results show that the SPRS caused a rapid increase of the total organic carbon concentration (up to 5794mg/L), and reductive dechlorination of TCE was significantly enhanced. TCE dechlorination byproducts were observed and up to 99% of TCE removal (initial TCE concentration=1872µg/L) was observed after 50 days of operation. The population of Dehalococcoides spp. increased from 4.6×10(1) to 3.41×10(7)cells/L after 20 days of operation. DNA sequencing results show that there were 31 bacterial species verified, which might be related to TCE biodegradation. Results demonstrate that the microbial analysis and real-time PCR are useful tools to evaluate the effectiveness of TCE reductive dechlorination.

Influence of clinical presentation on the outcome of acute B aortic dissection: evidences from IRAD.

AIM: In-hospital outcome of acute type B dissection (ABAD) is strongly related to preoperative aortic conditions. In order to clarify the influence of the clinical presentation on the outcome, we analyzed the patients of the International Registry of Acute Aortic Dissection (IRAD). All patients affected by complicated ABAD, enrolled in the IRAD from 1996-2004, were included. Complications were defined as the presence of shock, periaortic hematoma, spinal cord ischemia, preoperative mesenteric ischemia/infarction, acute renal failure, limb ischemia, recurrent pain, refractory pain or refractory hypertension (group I). All other patients were categorized as uncomplicated (group II). A comprehensive analysis was performed of all clinical variables in relation to in-hospital outcome. RESULTS: The overall in-hospital mortality among 550 patients was 12.4%. Mortality in group I (250 patients) was 20.0 %, compared to 6.1% in group II (300 patients) (P<0.001). Univariate predictors of ABAD complications were Marfan syndrome, abrupt onset of pain, migrating pain, any focal neurological deficits, need for higher number of diagnostic examinations and use of magnetic resonance and/or aortogram, abdominal vessels involvement at aortogram, larger descending aortic diameter, especially >6 cm, pleural effusion, and widened mediastinum on chest X-ray. Univariate predictors of a non complicated status were normal chest X-ray and medical management. In group I, in-hospital mortality following surgical and endovascular intervention were 28.6% and 10.1% (P=0.006), respectively. Independent predictors of overall in-hospital mortality included age >70 years, female gender, ECG showing ischemia, preoperative acute renal failure, preoperative limb ischemia, periaortic hematoma, and surgical management. The only independent variable protective for mortality was magnetic resonance as diagnostic test. CONCLUSION: ABAD is a heterogeneous disease that produces dissimilar clinical subsets, each of which can have specific clinical signs, management and in-hospital results. In IRAD ABAD uncomplicated patients, medical therapy was associated with best hospital outcome, while endovascular interventions were associated with better results than surgery when invasive treatments were required. Although selection bias may be possible, and irrespective of treatments, knowledge of significant risk factors for mortality may contribute to a better management and a more defined risk-assessment in patients affected by ABAD.

Remediation of TCE-contaminated groundwater using acid/BOF slag enhanced chemical oxidation.

The objective of this study was to evaluate the potential of applying acid/H(2)O(2)/basic oxygen furnace slag (BOF slag) and acid/S(2)O(8)(2-)/BOF slag systems to enhance the chemical oxidation of trichloroethylene (TCE)-contaminated groundwater. Results from the bench-scale study indicate that TCE oxidation via the Fenton-like oxidation process can be enhanced with the addition of BOF slag at low pH (pH=2-5.2) and neutral (pH=7.1) conditions. Because the BOF slag has iron abundant properties (14% of FeO and 6% of Fe(2)O(3)), it can be sustainably reused for the supplement of iron minerals during the Fenton-like or persulfate oxidation processes. Results indicate that higher TCE removal efficiency (84%) was obtained with the addition of inorganic acid for the activation of Fenton-like reaction compared with the experiments with organic acids addition (with efficiency of 10-15% lower) (BOF slag=10gL(-1); initial pH=5.2). This could be due to the fact that organic acids would compete with TCE for available oxidants. Results also indicate that the pH value had a linear correlation with the observed first-order decay constant of TCE, and thus, lower pH caused a higher TCE oxidation rate.

Treatment of petroleum-hydrocarbon contaminated soils using hydrogen peroxide oxidation catalyzed by waste basic oxygen furnace slag.

The contamination of subsurface soils with petroleum hydrocarbons is a widespread environmental problem. The objective of this study was to evaluate the potential of applying waste basic oxygen furnace slag (BOF slag) as the catalyst to enhance the Fenton-like oxidation to remediate fuel oil or diesel contaminated soils. The studied controlling factors that affect the removal efficiency of petroleum hydrocarbons included concentrations of H(2)O(2), BOF slag dosages, types of petroleum hydrocarbons (e.g., fuel oil and diesel), and types of iron mineral. Experimental results indicate that oxidation of petroleum hydrocarbon via the Fenton-like process can be enhanced with the addition of BOF slag. Results from the X-ray powder diffraction analysis reveal that the major iron type of BOF slag/sandy loam system was iron mineral (e.g., alpha-Fe(2)O(3) and alpha-FeOOH). Approximately 76% and 96% of fuel oil and diesel removal were observed (initial total petroleum hydrocarbon (TPH) concentration=10,000 mg kg(-1)), respectively, with the addition of 15% of H(2)O(2) and 100 g kg(-1) of BOF slag after 40 h of reaction. Because BOF slag contains extractable irons such as amorphous iron and soluble iron, it can act as an iron sink to supply iron continuously for Fenton-like oxidation. Results demonstrate that Fenton-like oxidation catalyzed by BOF slag is a potential method to be able to remediate petroleum-hydrocarbon contaminated soils efficiently and effectively.

Treatment of tetrachloroethylene-contaminated groundwater by surfactant-enhanced persulfate/BOF slag oxidation--a laboratory feasibility study.

The main objective of this study was to evaluate the feasibility of remediating tetrachloroethylene (PCE)-contaminated groundwater (with initial PCE concentration of approximately 20 mg L(-1)) via persulfate oxidation activated by basic oxygen furnace slag (S(2)O(8)(2-)/BOF slag) with the addition of biodegradable surfactant (Tween 80). Results indicate that only 15% of PCE can be removed in experiment with the addition of S(2)O(8)(2-) only (S(2)O(8)(2-)/PCE=30/1). PCE removal can be increased to 31% while both S(2)O(8)(2-) and BOF slag (10 g L(-1)) were added. This indicates that BOF slag was able to activate the persulfate oxidation mechanism, and cause the decrease in PCE concentration via oxidation process. Results also reveal that PCE degradation rates increased to 92% with the presence of Tween 80 (S(2)O(8)(2-)/Tween 80/PCE=30/2/1). In the presence of 10 g L(-1) BOF slag, the reaction rate constant (k(obs)) values were found to be 3.1 x 10(-3), 8.7 x 10(-3), 1.6 x 10(-2), and 5.8 x 10(-2)h(-1), as the S(2)O(8)(2-)/Tween 80/PCE molar ratios were 30/0/1, 30/0.5/1, 30/1/1, and 30/2/1, respectively. The reaction rate constant increased as the Tween 80 concentration increased. The significantly increased k(obs) could be caused by the enhanced solubilization of PCE by Tween 80. The increase in initial surfactant concentration would cause the increase in the solubilization of PCE, and thus, enhance the oxidation rate. This was confirmed by the total amount of chloride ions produced after the reaction. Results from this study indicate that BOF slag-activated persulfate oxidation enhanced by surfactant addition is a potential method to efficiently and effectively remediate chlorinated solvents contaminated groundwater.

[Clinical and immunological observations in myotonia].

Nine patients of myotonia, 5 being myotonia dystrophica and others being myotonia congenita, were studied for their clinical manifestations and immunological function. In the cases of myotonia dystrophica, they were inherited as autosomal dominant trait; the mean age onset was 17 years. Myotonia dystrophica was a diffuse systemic disorder. In addition to myotonia, there were muscle wasting, hatchet face, frontal baldness, pseudohypertrophy, etc. In the cases of myotonia congenita, none of the parents of the patients has clinical symptoms. The mean age onset was 8 years. The disease involved mainly the skeletal muscle. The immunological functions were studied in 7 patients, including 5 myotonia dystrophica and 2 myotonia congenita. In either myotonia dystrophica or myotonia congenita, the immunological functions were impaired widely, both humoral and cellular immunity. The level of serum IgG was lowered in both diseases.

[Prognosis of comatose patients on ventilator: a prospective study of brain death].

The concept of brain death is widely accepted in most countries. However, there are differences in the criteria for the diagnosis of brain death. In Taiwan, the diagnostic criteria of brain death has just been established. These criteria require strict preconditions to be fulfilled, necessary exclusions to be made, and adequate time of observation to ensure the irremediability of the disease. Tests of brainstem reflexes and apnea are then performed and should be repeated at an interval of at least 4 hours to establish the diagnosis. This prospective study was undertaken in order to examine the reliability of the present criteria. A total of 79 comatose patients (57 males and 22 females) on the ventilator were collected. Their ages ranged from 2.3 to 89 years, with a mean of 46.3 +/- 20.3 years. The preconditions or exclusions were not fulfilled in 5 patients (3 with drug intoxication, 1 with septicemia, and 1 due to an unknown cause). Among them, 1 with alcohol intoxication recovered well. Of 16 patients with hypoxic/ischemic brain damage, brain death was diagnosed in only 2; in the remaining 14 patients, 6 became vegetative and 8 died from cardiac arrest. Fifty-eight patients sustained structural brain damage, and brain death was diagnosed in 50 of these patients. The most frequent cause of brain death was head injury (31 cases), followed by intracerebral hemorrhage (11 cases). Of the 52 patients fulfilling the criteria of brain death, all sustained cardiac asystole in a limited interval of time (96% in 7 days).(ABSTRACT TRUNCATED AT 250 WORDS)