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Biomedical subjects

L Quan

Publications and source records attributed to L Quan.

At least 55 records · Page 3Linked to original sources
PubMed1999

Trends in unintentional drowning: the role of alcohol and medical care.

CONTEXT: During the last few decades, mortality from drowning has decreased in the United States for unknown reasons. It has been hypothesized that this decline may be due to decreased use of alcohol in and around water or improved medical treatment after a submersion. OBJECTIVES: To estimate changes in unintentional mortality due to submersion, estimate trends in drownings attributable to alcohol use, and assess the role of medical care in these mortality trends. DESIGN: A 21-year longitudinal study of case findings, from January 1, 1975, through December 31,1995. SETTING AND PARTICIPANTS: All residents of King County, Washington, who died unintentionally from submersion and 284 persons hospitalized for submersion who survived. MAIN OUTCOME MEASURES: Changes in submersion-related mortality incidence over time, proportion of this mortality that could be attributed to alcohol use, changes over time in the case-fatality rate of treated patients, and estimate of deaths prevented in 1995 compared with projected estimates had there been no change in incidence since 1975. RESULTS: There were 539 deaths due to drowning in King County during 21 years. Mortality rates during this period declined by 59% (95% confidence interval [CI], -70% to -46%). The incidence of death attributable to alcohol use decreased by 81% (95% CI, -91% to -57%); this could account for 51% of deaths prevented in 1995. Among 249 comatose patients who received prehospital care, 205 died; the odds of survival decreased 40% over 21 years (P = .40). Among 101 comatose patients who were hospitalized, 63 died; the odds of survival decreased 29% (P = .75). The incidence of survival of comatose hospital patients decreased by 29% from 1975 to 1995 (95% CI, -78% to +125%). We found no evidence that trends in medical treatment prevented any deaths due to drowning in 1995. CONCLUSIONS: Drowning incidence in King County, Washington, declined because of a decrease in severe submersion episodes rather than an increase in success of medical interventions. Our data support the theory that less use of alcohol around water prevents some deaths. About half of the decrease was unexplained.

Alcoholic Intoxication↗
PubMed1999

Factors influencing the potential use of Aliquat 336 for the in situ extraction of carboxylic acids from cultures of Pseudomonas putida.

The use of extraction techniques to alleviate product inhibition in bioprocesses is one of a number of potential separation methods. However, the intimate contact of an organic phase with the broth implies that the organic components of this phase may be present in the aqueous phase at saturation levels. The quaternary amine Aliquat 336 (trioctyl/decylmethylammonium entity), dissolved in octan-1-ol showed no inhibition on the growth of Pseudomonas putida, at least with respect to molecular toxicity. Nevertheless, it is important to point out two main effects of Aliquat 336 associated with its ion exchange properties. It is able (1) to complex hydroxyl ions and therefore drastically lower the pH of the broth and (2) release its counter ion through these exchanges. Therefore, a strict control of the pH of the cultivation must be conducted, with the constraint that Ps. putida has an optimal pH growth of 7.4-7.5. The pH range tolerated by this strain is, however, between 5.0 and 9.0. In addition, the counter ion of Aliquat 336 needs to be carefully chosen and HSO4- should be preferred to Cl-.

Biotechnology↗
PubMed1999

Pulmonary embolism: a case of sudden unexpected death in a psychiatric hospital.

We report a case of suspected fatal physical abuse in which the cause of death was proved to be pulmonary embolism. A patient with mental retardation presenting aggressive behavior was admitted to a psychiatric hospital and was treated with major tranquilizers. She suddenly died subsequent to an angina-like attack. For several days before her death, she had been confined to her bed because of very low physical and mental activity. Bruises and abrasions were observed on the extremities, suggesting the recent restraints. There was no positive evidence of physical abuse. At autopsy, the cause of death was elucidated to be pulmonary embolism originating from thrombi in the left popliteal vein. This case indicates the risk of pulmonary embolism in immobilized patients in psychiatric hospitals.

Journal Article↗
PubMed1999

A sudden death due to cardiac conduction system injury from a blunt chest impact.

We report a case of sudden death due to cardiac conduction system injury from a blunt chest impact. A 20 year old male, kicked in the precordial region, lost consciousness, and was confirmed dead on arrival at a hospital emergency care unit. According to his friends, they played a golf competition accompanied with a physical punishment. The victim, losing the game, allowed the winner to give him several kicks in the chest. Although well prepared against each kick, he fell down instantaneously after the final impact, and death was confirmed at a hospital. There was no apparent sign of injury on the body surface. At autopsy, there was no evident subcutaneous or intramuscular hemorrhages, rib or sternum fracture. Subendocardial hemorrhage in the region of the atrioventricular node and a contusion extending from the posterior wall of the left ventricle to the upper ventricular septum were observed. Histological examination revealed injury of atrioventricular node and His' bundle. Although the cardiac injury including contusion of the myocardium itself was not so extensive, it was considered that arrhythmia was induced by the cardiac conduction system failure, which was considered to be the cause of death.

Journal Article↗
PubMed1999

Evaluation of a drowning prevention campaign in King County, Washington.

OBJECTIVES: A three year drowning prevention campaign focused on increasing the use of life vests among children 1-14 years old. An evaluation was conducted to determine campaign awareness, change in ownership and use of life vests by children, and predictors of life vest use. SETTING: King County, Washington. METHODS: Four telephone surveys were conducted with parents before, during, and after the campaign. RESULTS: The campaign was recalled by 50% of families surveyed. From before to after the campaign, reported life vest use by children on docks, beaches, or at pools increased from 20% to 29% (p < 0.01) and life vest ownership for children increased from 69% to 75% (p = 0.06). Among parents aware of the campaign, reported child life vest use increased from 20% to 34% (p < 0.001) and ownership increased from 69% to 80% (p < 0.01). Among families unaware of the campaign, neither life vest use nor ownership changed significantly. Children were more often reported to wear life vests if a parent knew of the campaign, was confident fitting the vest, was younger than 40 years, felt the child could not swim well, and owned a life vest for the child. CONCLUSIONS: A community-wide drowning prevention campaign resulted in a significant, although modest, increase in reported life vest use and ownership among children.

Accident Prevention↗
PubMed1999

Impaired cerebral vasodilator responses to NO and PDE V inhibition after subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is associated with impaired nitric oxide (NO)-mediated cerebral vasodilatation. We tested the hypothesis that SAH causes alterations in the production of, hydrolysis of, or responsiveness to cGMP in the rat basilar artery in vivo. Rats were injected with saline or autologous blood into the cisterna magna. Two days later, effects of vasoactive drugs on basilar artery diameter were examined using a cranial window preparation. Vasodilator responses to ACh, sodium nitroprusside (SNP), and low concentrations (</=10(-5) M) of zaprinast, an inhibitor of phosphodiesterase V (PDE V), were impaired in SAH rats (P < 0.05). In contrast, vasodilator responses to adenosine and 8-BrcGMP were similar in control and SAH rats. Vasoconstrictor responses to 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one, an inhibitor of soluble guanylate cyclase, were unaffected by SAH. In the presence of zaprinast (10(-5)-10(-4) M), responses to ACh and SNP were equivalent in control and SAH rats. Thus an increased rate of cGMP hydrolysis by PDE V may be a major factor contributing to the impairment of NO-mediated cerebral vasodilatation after SAH.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1999

Near-drowning.

Explore the source record for details and available documents.

Adolescent↗
PubMed1999

[Effects of space flight on medicinal plant Agastache rugosa (Fisch. et Mey.) O. Ktze].

OBJECTIVE: To substantiate the effect of space conditions on medicinal plants. METHODS: The seeds of Agastache rugosa were set up in retrievable satellites. After returning to earth, the changes of isozymes of peroxidases, esterase and soluble proteins were studied. RESULTS: The peroxidase activity and protein content of the weightless group were a little lower than those of the earth controlled group, while these two items of the hit group were higher than those of the earth controlled group. The electrophoresis patterns of isoperoxidases and isoeasterase of these three groups, as well as the protein patterns of the weightless group and the earth controlled group were found alike. But the protein patterns of the hit group were different from those of the other two groups. CONCLUSION: The effect of weightlessness is smaller than that of the high energy heavy ions on Agastache rugosa. Different plants have different susceptibility to space conditions.

China↗
PubMed1999

[Ultrastructural changes after space flight in Platycodon grandiflorum (Jacq.) DC].

OBJECTIVE: To substantiate the effect of space conditions on medicinal plants. METHOD: The seeds of platycodon grandiflorumg were set up in retrievable satellites. After returning to earth, the ultrastructural changes of leaves were studied. RESULT: Under light microscope, the leaf tissue structure of the flight group and the earth controlled group were alike and under electron microscope, some differences could be found in the nucleus and choloroplasts between the two groups. CONCLUSION: Space environment has some effect on Platycodon grandiflorum, and the effect needs to be further explored.

Cell Nucleus↗
PubMed1999

[Studies on the effects of space flight on Carthamus tinctorius L].

OBJECTIVE: To substantiate the effects of space condition of medicinal plants. METHODS: The seeds of Carthamus tinctorius were sent to space in retrievable satellites. After returning to earth, the seeds were stored at 0-4 degrees C, and cultured in the test field in the spring of next year. The peroxidases, soluble proteins and ultrastructure of leaves were studied in flowering stage. RESULTS: The peroxidase activity of the flight group was lower than that of the earth controlled group, and the protein content of the flight group was higher than that of the earth controlled group. The main bands in electrophoresis patterns of peroxidases and proteins were alike, and some bands were different. Some changes could be observed in the ultrastructure of chloroplast between the flight group and the earth controlled group. CONCLUSION: Space environments have some effect on Carthamus tinctorius. The results of this experiment are consistent with those of the previous experiment.

Carthamus tinctorius↗
PubMed1999

[Effect of space flight on ultrastructure in medicinal plant Datura innoxia Mill].

OBJECTIVE: To substantiate the effect of space environment on medicinal plants. METHOD: The seeds of Datura innoxia were set up in retrievable satellites. After returning to earth, the ultrastructural changes were observed by means of electron microscope. RESULTS: In cells of weightless group and hit group, some changes were found in chloroplast grana, starch grains and vesicles in chloroplasts. No obvious changes were observed in nuclei. CONCLUSION: Space environment has some effect on the ultrastructure in D. innoxia, and chloroplast is more sensitive to space environment than other organs.

Chloroplasts↗
PubMed1998

Performance of advanced resuscitation skills by pediatric housestaff.

OBJECTIVE: To describe pediatric housestaff resuscitation experience and their ability to perform key resuscitation skills. DESIGN: Cohort study of 63 pediatric residents in a university-based training program. PARTICIPANTS AND METHODS: Investigators observed, scored, and timed resident performance on 4 key resuscitation skills. Cognitive ability was tested with 4 written scenarios. Housestaff provided self-reports of the number of months since their last American Heart Association Pediatric Advanced Life Support course, number of mock and actual codes attended, number of times skills were performed, and self-confidence with respect to resuscitation. RESULTS: A total of 45 pediatric residents (71%) participated. Median cognitive score was 5 (range, 1-5). Of all residents, 44 (97%) successfully bag mask-ventilated the mannequin; 24 (53%) and 36 (80%) used the correct bag and mask size, respectively. Thirty-nine residents (87%) placed a tube in the mannequin trachea, 12 (27%) checked that suction was working prior to intubation, and 30 (67%) chose the correct endotracheal tube size. Forty residents (89%) discharged the defibrillator, and 25 (56%) and 32 (71%) correctly chose asynchronous mode and infant paddles, respectively. Thirty-eight residents (84%) inserted an intraosseous line; 35 (78%) had correct placement. Median times for successful skill completion were 83 seconds for bag mask ventilation, 136 seconds for intubation, 149 seconds for defibrillation, and 68 seconds for intraosseous line placement. CONCLUSION: Pediatric housestaff previously trained in pediatric advanced life support were generally able to reach the end point of 4 key resuscitation skills but less frequently performed the specific subcomponents of each skill. This poor performance and the prolonged time to skill completion suggest the need for greater attention to detail during training.

Adult↗
PubMed1998

Pediatric wilderness recreational deaths in western Washington State.

STUDY OBJECTIVE: To determine the causes and characteristics of pediatric recreational wilderness deaths. METHODS: All deaths of children between 12 months and 20 years of age involving a wilderness recreational activity in 5 western Washington counties between 1987 and 1996 were identified by medical examiners' logs. Univariate analysis was used to examine variables such as age, gender, activity, mechanism of injury, adult presence, blood alcohol level, safety equipment, and mode of evacuation. RESULTS: Of 40 cases meeting inclusion criteria, 90% involved male subjects and 83% of victims were 13 to 19 years old. Hiking (33%), swimming (20%), and river rafting (10%) were the most common activities. Death was most often by drowning (55%) or closed head injury (26%). No victim was alone. All children younger than 10 years of age were accompanied by an adult, in contrast to only 26% of individuals 10 years or older. Only 4 victims had drugs or alcohol in their system. No victim wore a personal flotation device or helmet, and only 5% had foul weather gear. Although nearly one third of victims were transported by airlift, more than half of the victims were dead at the scene. CONCLUSION: Males and teenagers were the 2 major risk groups for recreational wilderness deaths. Traditional activities such as hiking and swimming were the most common causes of death. Children younger than 10 years died despite the presence of an adult, whereas teenagers were usually with groups of peers. The majority of victims were not prepared for adverse events with basic safety equipment.

Adolescent↗
PubMed1998

Are life vests worn? A multiregional observational study of personal flotation device use in small boats.

OBJECTIVE: Although life vest use is thought to prevent drowning, their use by boaters has not been described. This study sought to determine the use of personal flotation devices (PFDs) in small boats. METHODS: Boaters were observed between April and June 1995 in Washington and Oregon and classified by their age, gender, PFD use, and boat type. RESULTS: Among 4181 boaters, 25% wore a PFD. Use was highest in < 5 year olds (91%) and lowest in those over 14 years (13%). Those in kayaks were most likely (78%) and those in motor boats (19%) were least likely to wear a PFD. Females were more likely to wear a PFD than males (relative prevalence 1.5, 95% confidence interval 1.3 to 1.6). When a child less than 15 years was in a boat with an adult, PFD use was 65% if no adult wore a PFD and 95% if at least one accompanying adult wore a PFD (p = 0.001). CONCLUSIONS: Generally, PFD use by boaters was low in the Northwestern US. Efforts to increase PFD use should target adolescents, adults and specific boating populations, especially those in motor boats.

Adolescent↗