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1.
Arch Pediatr Adolesc Med ; 154(10): 1049-54, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11030858

RESUMO

OBJECTIVE: To evaluate the effectiveness of an educational intervention on pediatric residents' resuscitation fund of knowledge, technical skills, confidence, and overall performance. DESIGN: Prospective, nonconcurrent, controlled interventional trial. SETTING: Urban pediatric tertiary care hospital. PARTICIPANTS: An intervention group (IG) of 28 pediatric residents graduating in 1997, and a control group (CG) of 30 pediatric residents graduating in 1996. INTERVENTIONS: Resuscitation course with didactic lectures and skills practice stations, as well as a minimum of 3 practice mock resuscitations with immediate feedback throughout postgraduate year 3. MAIN OUTCOME MEASURES: Fund of knowledge, using the Pediatric Advanced Life Support test and short answer test; technical skills, using the Airway and Vascular Access Skills Assessment; experience and confidence, using an anonymous survey; and overall performance, evaluated using a videotaped mock resuscitation test. RESULTS: The IG scored better on the short answer test (P<.001). A larger number of IG residents were successful in the completion of ancillary airway maneuvers and femoral vascular access (P =.02), as well as endotracheal intubation (P =.004) and intraosseous access (P =.002). The IG was more confident in their leadership role (P =.0001) and technical skills (P =.05). Trends toward improved overall performance were noted for the IG mock resuscitations. Residents in the IG were more likely to assess the airway in fewer than 2 minutes (P =.02), recognize the threat to life in fewer than 5 minutes (P =.02), and complete the primary survey in a timely fashion (P =.05). They required fewer prompts (P =.04) and made fewer mistakes (P =.07). CONCLUSIONS: A structured, formal curriculum can improve the necessary fund of knowledge, skills, confidence, and leadership required for resuscitation.


Assuntos
Educação de Pós-Graduação em Medicina/métodos , Internato e Residência/métodos , Corpo Clínico Hospitalar/educação , Pediatria/educação , Ressuscitação/educação , Ensino/métodos , Competência Clínica/normas , Currículo , Humanos , Avaliação de Resultados em Cuidados de Saúde , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Fatores de Tempo , Gravação de Videoteipe
2.
Pediatrics ; 106(1 Pt 1): 100-4, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10878156

RESUMO

OBJECTIVE: The American Academy of Pediatrics recommends forensic evidence collection when sexual abuse has occurred within 72 hours, or when there is bleeding or acute injury. It is not known whether these recommendations are appropriate for prepubertal children, because few data exist regarding the utility of forensic evidence collection in cases of child sexual assault. This study describes the epidemiology of forensic evidence findings in prepubertal victims of sexual assault. METHODS: The medical records of 273 children <10 years old who were evaluated in hospital emergency departments in Philadelphia, Pennsylvania, and had forensic evidence processed by the Philadelphia Police Criminalistics Laboratory were retrospectively reviewed for history, physical examination findings, forensic evidence collection, and forensic results. RESULTS: Some form of forensic evidence was identified in 24.9% of children, all of whom were examined within 44 hours of their assault. Over 90% of children with positive forensic evidence findings were seen within 24 hours of their assault. The majority of forensic evidence (64%) was found on clothing and linens, yet only 35% of children had clothing collected for analysis. After 24 hours, all evidence, with the exception of 1 pubic hair, was recovered from clothing or linens. No swabs taken from the child's body were positive for blood after 13 hours or sperm/semen after 9 hours. A minority of children (23%) had genital injuries. Genital injury and a history of ejaculation provided by the child were associated with an increased likelihood of identifying forensic evidence, but several children had forensic evidence found that was unanticipated by the child's history. CONCLUSIONS: The general guidelines for forensic evidence collection in cases of acute sexual assault are not well-suited for prepubertal victims. The decision to collect evidence is best made by the timing of the examination. Swabbing the child's body for evidence is unnecessary after 24 hours. Clothing and linens yield the majority of evidence and should be pursued vigorously for analysis.


Assuntos
Abuso Sexual na Infância/diagnóstico , Medicina Legal , Criança , Pré-Escolar , Feminino , Medicina Legal/métodos , Humanos , Lactente , Masculino , Exame Físico , Estudos Retrospectivos
3.
Pediatr Emerg Care ; 16(2): 73-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10784204

RESUMO

OBJECTIVE: To describe pediatric housestaff knowledge, experience, confidence in pediatric resuscitations and their ability to perform important resuscitation procedures during the usual training experience. DESIGN AND PARTICIPANTS: Cohort study of PGY-3 level residents in a ACGME accredited pediatric residency training program at a large, tertiary care children's hospital. METHODS: Fund of knowledge was assessed by administering the standardized test from the Pediatric Advanced Life Support (PALS) Course in addition to a supplemental short answer test requiring clinical problem-solving skills. Procedural skills were evaluated through observation of the resident performing four procedures during a skills workshop using a weighted step-wise grading sheet. Resident experience and confidence was quantified using an anonymous survey. RESULTS: Ninety-seven percent of residents participated. Residents achieved high scores on the standardized PALS test (93.2%+/-5.5), but performed less well when answering more complicated questions (60.0%+/-9.9) on the short answer test. No resident was able to successfully perform both basic and advanced airway skills, and only 11% successfully completed both vascular skills. Although residents were overall confident in their resuscitation skills, performance in the skill workshop revealed significant deficits. For example, only 18% performed ancillary airway maneuvers properly. None of the residents performed all four skills correctly. Experience in both real and mock resuscitations was infrequent. Residents reported receiving feedback on their performance less than half of the time. Over 89% of them felt that resuscitation knowledge and skill were important for their future chosen career. CONCLUSION: Pediatric residents infrequently lead or participate in real or mock resuscitations. Although confident in performing many of the necessary resuscitation skills, few residents performed critical components of these skills correctly. Current pediatric residency training may not provide sufficient experience to develop adequate skills, fund of knowledge, or confidence needed for resuscitation.


Assuntos
Internato e Residência , Pediatria/educação , Ressuscitação/educação , Atitude do Pessoal de Saúde , Competência Clínica , Estudos de Coortes , Hospitais Pediátricos , Humanos , Manequins , Philadelphia , Resolução de Problemas
4.
Clin Pediatr (Phila) ; 38(7): 401-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10416096

RESUMO

The purpose of this study was to identify the causes and epidemiology of back pain in children who present to the emergency department. All children who presented to an urban pediatric emergency department (ED) during a 1-year period with the chief complaint of back pain were examined and evaluated with a uniform questionnaire. This was completed at the time of the ED visit in 48%, and within 48 hours in 52%. During a 1-year period, 225 children with a complaint of back pain were evaluated. The mean age was 11.9 +/- 4 years and 60% were female. Onset was acute (< or = 2 days) in 59%, and chronic (> or = 4 weeks) in only 11.6%. Pain awakened children from sleep in 47%, and caused 52% to miss school or work. The most common diagnoses were direct trauma (25%), muscle strain (24%), sickle cell crises (13%), idiopathic (13%), urinary tract infection (5%), and viral syndrome (4%). Radiographs of the back were rarely helpful. About 5% required hospital admission; one half of these were attributed to sickle cell crises. We conclude that back pain is an uncommon reason for children to present to an emergency department. When present, pediatric back pain is most often musculoskeletal, associated with an acute infectious illness or a traumatic event. Although the etiology is rarely serious, back pain often affects the daily activities of symptomatic children.


Assuntos
Dor nas Costas/etiologia , Doença Aguda , Dor nas Costas/diagnóstico por imagem , Dor nas Costas/psicologia , Criança , Pré-Escolar , Doença Crônica , Serviço Hospitalar de Emergência , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/diagnóstico por imagem , Humanos , Lactente , Masculino , Grupos Raciais , Radiografia , Escoliose/complicações , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem
5.
Arch Pediatr Adolesc Med ; 152(12): 1220-4, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9856433

RESUMO

OBJECTIVE: To determine if trauma center protocols affect the number of tests and consultations performed and the length of time spent in the emergency department or hospital. DESIGN: A retrospective review and comparison of treatment for children with isolated head injury admitted to the emergency department before trauma center designation (group 1, 1985), and 5 years after implementation of trauma center protocols (group 2, 1991). SETTING: Urban children's hospital, level I trauma center. RESULTS: One hundred sixty-five children met the enrollment criteria in 1985 and 162 met the criteria in 1991. Falls were the predominant mechanism of injury (55%) for both years. For patients with moderate injury (Glasgow Coma Scale score, 9-12) or severe injury (Glasgow Coma Scale score, <9), there was no difference in radiographic or laboratory evaluation. For patients with minimal head injury (Glasgow Coma Scale score, 15, no loss of consciousness, amnesia, seizure, focal neurologic findings, or persistent symptoms) and minor head injury (Glasgow Coma Scale score, >12, and loss of consciousness or amnesia), more radiologic and laboratory studies were done in 1991 that showed no clinically significant abnormalities. Patients with minimal head injury in group 2 were 14 times more likely to have cranial computed tomographic scans performed (95% confidence interval [CI], 3.4-67); 11 times more likely to have cervical spine radiographs (95% CI, 2.2-76.6); and 23 times more likely to have hepatic enzymes obtained (95% CI, 3-491). These differences persisted when analyzed by both the age of the patient and mechanism of injury. CONCLUSIONS: Application of trauma system protocols to isolated head injury patient evaluation results in increased use of laboratory and radiologic services. These practices have the potential to increase the cost of medical care without significantly improving outcome.


Assuntos
Protocolos Clínicos , Traumatismos Craniocerebrais/diagnóstico , Diagnóstico por Imagem/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Centros de Traumatologia/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/etiologia , Diagnóstico Diferencial , Hospitais Pediátricos , Humanos , Prontuários Médicos , Razão de Chances , Philadelphia , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Saúde da População Urbana
6.
Ann Emerg Med ; 32(6): 698-702, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9832667

RESUMO

STUDY OBJECTIVE: To design and implement a plan for emergency department staffing and additional space to reduce waiting time and the rate of patients leaving without being seen during the viral epidemic season. METHODS: The study was conducted in the ED of a tertiary care children's hospital. We compared 24,657 children who presented for care between November 1996 and March 1997 (VESAS plan enacted) with 24,012 children who presented for care during the same period in the preceding year. VESAS (Viral Epidemic Supplemental Attending and Staff), an additional team of personnel, was on call for the viral epidemic season and was called to work if the hourly ED census that day was 25% or more of the past year's average hourly patient volume. Extra examination rooms were made available in space contiguous to the ED. Interval data, "left without being seen" rates, and ED census were monitored and compared with the previous year's data. RESULTS: The VESAS team was used for 32% of the days during the 4-month intervention period. The left-without-being-seen rate was reduced by 37% (95% confidence interval, 33% to 41%). The average time from arrival to consultation with a physician was decreased by 15 minutes (95% confidence interval, -10 to -20) for all patients. Waiting times were most markedly reduced for less acutely ill or injured patients, although a modest decrease was also observed in patients with more severe illnesses or injuries (-10 minutes). The percentage of lesser-severity patients seen in an urgent care area was increased from 35% to 51%. CONCLUSION: VESAS, a plan for providing space and personnel to handle an increased volume of patients that can be activated on the basis of hourly census data, was successful as judged by waiting times and percentage of patients who left without being seen.


Assuntos
Ocupação de Leitos/tendências , Serviço Hospitalar de Emergência/estatística & dados numéricos , Admissão e Escalonamento de Pessoal/organização & administração , Recursos Humanos em Hospital/provisão & distribuição , Estações do Ano , Viroses/terapia , Criança , Hospitais Pediátricos , Hospitais Urbanos , Humanos , Philadelphia/epidemiologia , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Gerenciamento do Tempo , Viroses/epidemiologia , Listas de Espera , Recursos Humanos
7.
Arch Pediatr Adolesc Med ; 151(8): 840-4, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9265889

RESUMO

OBJECTIVE: To develop a structured process to gain resident input into the improvement of their educational experience by (1) taking a small amount of resident time and effort, (2) fostering the generation of new ideas, (3) allowing the prioritization of ideas, (4) generating implementation plans for the ideas, and (5) offering the participants relative anonymity. DESIGN: Cross-sectional survey and group sessions. SETTING: Urban, university-based children's hospital. PARTICIPANTS: Members of the pediatric residency program in the 1993-1994 academic year. INTERVENTIONS AND RESULTS: The process was piloted for an emergency department rotation and borrows aspects of the Delphi Technique, Nominal Group Technique, and focus group methods. A survey regarding an emergency department rotation was distributed to all pediatric residents, and the 10 most commonly noted problems were compiled. These problems were brought to group sessions held for each level of training. Problems not listed were added if they were mentioned during the session; however, no problem was removed from the list. The sessions, designed to offer relative anonymity to the residents, included an initial clarification period, a round-robin prioritization of ideas, and an open discussion designed to generate solutions. Resident-generated solutions resulting from the group sessions were reviewed by the attending staff, and changes were implemented during the next year. CONCLUSION: The technique that we developed is a practical and time-efficient method of incorporating resident perspectives into the improvement of a rotation.


Assuntos
Atitude do Pessoal de Saúde , Medicina de Emergência/educação , Grupos Focais/normas , Internato e Residência/organização & administração , Corpo Clínico Hospitalar/psicologia , Pediatria/educação , Inquéritos e Questionários/normas , Estudos Transversais , Técnica Delphi , Humanos , Descrição de Cargo , Inovação Organizacional , Projetos Piloto , Carga de Trabalho
8.
Acad Emerg Med ; 4(3): 202-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9063547

RESUMO

OBJECTIVE: To assess the utility of serum and cerebrospinal fluid (CSF) prolactin levels for identifying children who have experienced seizures. METHODS: A prospective cohort study was performed in a pediatric ED at an urban children's hospital. A convenience sample of children underwent blood and CSF analyses in the ED over a 2-year period. RESULTS: Thirty-five children (aged 3 months-15 years) with generalized tonic-clonic seizures and 48 ill control patients were studied. Both groups included febrile and afebrile patients. The patient characteristics in the seizure and control groups were similar with respect to age, fever, current medications, and blood, urine, and CSF cultures. When serum prolactin levels were assigned age-adjusted dichotomous values of "elevated" or "normal," the rates of elevation between the seizure and control patients were different (p < 0.001). The positive and negative predictive values of these age-adjusted levels were 68% (95% CI 47-85%) and 76% (95% CI 61-87%), respectively. The mean CSF prolactin levels of the seizure and control groups were not significantly different. In addition, there was no single threshold CSF prolactin level that could delineate seizure patients from control patients. CONCLUSIONS: Age-adjusted serum prolactin levels are useful only as an adjunct in the prospective evaluation of the individual pediatric patient for epileptic seizure activity. CSF prolactin levels are not useful in the diagnosis of generalized seizures in children in the acute care setting.


Assuntos
Prolactina/sangue , Prolactina/líquido cefalorraquidiano , Convulsões/diagnóstico , Adolescente , Envelhecimento/sangue , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Humanos , Lactente , Estudos Prospectivos , Valores de Referência , Convulsões/sangue , Convulsões/líquido cefalorraquidiano
9.
Compr Ther ; 21(12): 711-18, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8789135

RESUMO

Children account for 30% of visits to emergency departments, and approximately 5% of these children have serious illness requiring immediate intervention. Over the past decades, as medical knowledge and application have eradicated many illness and rendered others curable, trauma has emerged as the leading cause of morbidity and mortality after the first year of life. However, all children remain vulnerable to infection and its consequences in the first year and beyond the first year. Additionally, over this time span, there are more children with chronic complicated health problems who survive yet remain dependent on sophisticated medical care. Intuitively, prompt recognition of the very ill child and the execution of the immediate and necessary interventions may be life saving. The ability to accomplish this requires a knowledge of the common culprits resulting in serious illness, an understanding of how they manifest in the physical examination, and an array of technical skills utilizing appropriate specially sized equipment. Furthermore, an understanding of child development and the ability to interpret the physical examination of the children of different ages is essential. This article will attempt to simplify this seemingly overwhelming task by considering a common thread in all critical illness.


Assuntos
Estado Terminal , Pediatria/métodos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/terapia , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/terapia , Criança , Humanos , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/terapia
10.
Ann Emerg Med ; 25(3): 344-8, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7864474

RESUMO

STUDY OBJECTIVE: To evaluate the risk factors associated with bathtub submersion injury and their relationship to child abuse and neglect. DESIGN: Retrospective chart review. SETTING: An urban children's hospital. PARTICIPANTS: Any child sustaining a bathtub near-drowning over the 10-year period from 1982 to 1992. INTERVENTIONS: None. RESULTS: Twenty-one patients were treated for bathtub near-drownings during the 10-year period, accounting for 24% of all submersion injuries. A significant number (67%) had historic and/or physical findings suspicious for abuse or neglect, including incompatible history for the injury, other physical injuries, previous child abuse reports, psychiatric history of the caretaker, and/or psychosocial concerns noted in the chart. The mortality rate of 42% was significant. No demographic characteristics identified the children at risk. CONCLUSION: Many children who are injured in the bathtub suffer from abuse or neglect. Medical evaluation should include social work consultation and a search for other accompanying injuries.


Assuntos
Maus-Tratos Infantis/diagnóstico , Afogamento Iminente/etiologia , Criança , Pré-Escolar , Feminino , Hospitais Urbanos , Humanos , Lactente , Masculino , Pennsylvania , Estudos Retrospectivos , Fatores de Risco
11.
Mutat Res ; 308(1): 33-42, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7516484

RESUMO

The mutagenic effects of azide (N3-) anion in bacterial test systems require the formation of the novel mutagenic metabolite, 3-azido-L-alanine (AZAL). Although the mechanism of AZAL-induced mutagenicity is unknown, subsequent bioactivation of this metabolite appears likely. Earlier studies have shown that other azide-containing amino acids are mutagenic as well. In fact, the mutagenic potency of the synthetic AZAL homologue, L-2-amino-4-azidobutanoic acid (HomoAZAL), was several times that of AZAL. To gain insight into the biochemical processing and mutagenicity of azido amino acids in Salmonella typhimurium, several specifically deuterium-labeled azido amino acids have been prepared and tested for mutagenic potency. In addition, the effect of (aminooxy)acetic acid (AOA) (a potent inhibitor of pyridoxal-dependent processes) on AZAL-induced mutagenesis was examined. The results showed that 2-deuterium substitution of AZAL resulted in a slight increase in mutagenic potency, while AOA treatment resulted in no change in AZAL potency. Taken together these findings did not support the involvement of pyridoxal-dependent processes in AZAL bioactivation. In contrast, deuterium substitution adjacent to the azide group in HomoAZAL and 5-azido-L-norvaline (N3-Norval) resulted in a large decrease in mutagenic potency when compared to the non-deuterium labeled compounds. These observations are consistent with a bioactivation mechanism involving rate-limiting C-H bond cleavage in the formation of the ultimate mutagen. Moreover, this effect of deuterium labeling points to processing of the azide-containing side chain as a key feature in the mutagenic activation mechanism.


Assuntos
Alanina/análogos & derivados , Azidas/farmacologia , Alanina/farmacologia , Biotransformação , Deutério , Marcação por Isótopo , Testes de Mutagenicidade , Mutagênicos , Salmonella typhi/efeitos dos fármacos , Salmonella typhi/genética
12.
Crit Care Med ; 21(3): 368-73, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8440106

RESUMO

OBJECTIVES: a) To report the neurologic outcome of a series of near-drowning victims treated with supportive management without aggressive cerebral resuscitation; and b) to identify patient characteristics that indicate prognosis and guide therapy at the scene, the Emergency Department, and in the intensive care unit (ICU). DESIGN: Retrospective review of all near-drowning patients requiring admission to the ICU over a 6-yr period (1/1/82 to 12/31/88). Hospital records were examined for the circumstances of submersion and rescue, patient condition on arrival in the Emergency Department and ICU, treatments, hospital course, and ultimate outcome. SETTING: Emergency departments of the referring hospital and ICU of Children's Hospital. PATIENTS: Forty-four pediatric submersion victims were treated with therapy limited to the support of vital functions. Three patients who met cold-water drowning criteria were excluded from the analysis for predictors of neurologic outcome. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In our warm-water near-drowning patients, 56% survived neurologically intact, 32% survived in a persistent vegetative state, and the remaining 32% died. Unreactive pupils in the Emergency Department and a Glasgow Coma Score of < or = 5 on arrival to the ICU were the best independent predictors of poor neurologic outcome (odds ratio and 95% confidence intervals 374 [17 to 16,000] and 51 [5 to 2,200], respectively). However, no predictor was absolute and two nonhypothermic patients who arrived to the Emergency Department without vital signs, requiring cardiopulmonary resuscitation and cardiotonic medications, had full neurologic recovery. CONCLUSIONS: Our results cast further doubt on the utility of aggressive forms of cerebral monitoring and resuscitation and emphasize the need for initial full resuscitation in the Emergency Department.


Assuntos
Serviço Hospitalar de Emergência , Unidades de Terapia Intensiva , Afogamento Iminente/terapia , Ressuscitação , Adolescente , Reanimação Cardiopulmonar , Criança , Pré-Escolar , Coma/etiologia , Feminino , Humanos , Lactente , Pressão Intracraniana , Masculino , Monitorização Fisiológica , Afogamento Iminente/complicações , Afogamento Iminente/mortalidade , Prognóstico , Estudos Retrospectivos , Fatores de Risco
13.
J Appl Behav Anal ; 25(4): 885-92, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1478911

RESUMO

The Colorado Occupant Protection Project (COPP) intervention provided police with brief instruction concerning the importance of citations for drivers' failure to use child safety seats and special coupons to accompany citations. Coupons were exchangeable by drivers for a safety seat and brief training in its use, plus a waiver of the $50 citation fine. Over 4.5 years of archival records were employed, using an ABA design and a comparison community to evaluate the program. Few tickets were issued for nonuse of safety seats during the 3-year baseline in either community. Citations for nonuse of safety seats increased to over 50 per month during the intervention period at the test site, whereas rates remained essentially zero at the comparison site. After the COPP intervention was removed at the intervention site, citation rates for nonuse of safety seats decreased to about 15 per month. Differences between intervention conditions and settings were statistically significant. During the intervention, officers were 44 times more likely to write citations than were controls. Results suggested that a behavioral program can increase police citation writing for child protection purposes.


Assuntos
Proteção da Criança/legislação & jurisprudência , Educação em Saúde/legislação & jurisprudência , Cintos de Segurança/legislação & jurisprudência , Controle Social Formal , Ferimentos e Lesões/prevenção & controle , Terapia Comportamental , Criança , Pré-Escolar , Colorado , Humanos , Lactente
14.
Br J Surg ; 78(12): 1452-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1773324

RESUMO

The purpose of this prospective study was to determine the clinicopathological significance of necrotic areas demonstrated by rapid-bolus contrast-enhanced computed tomography (CT) in patients with biochemically predicted severe pancreatitis. Although CT necrosis occurred significantly more frequently in patients with clinically severe (ten of 12) compared with mild (seven of 20) pancreatitis (P less than 0.025), seven of 17 (41 per cent) patients with CT necrosis developed clinically mild pancreatitis and six of ten (60 per cent) patients with clinically severe pancreatitis and CT necrosis recovered with conservative management. The site and extent of CT necrosis did not correlate with disease severity. Fine-needle aspiration cytology, operative and post-mortem findings and endoscopic retrograde cholangiopancreatography examinations all strongly suggested that CT necrosis represents true pancreatic necrosis. We conclude that the finding of CT necrosis is not in itself an indication for operative intervention, but that rapid-bolus contrast-enhanced dynamic CT greatly facilitates the planning and execution of surgical therapy.


Assuntos
Pancreatite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Meios de Contraste , Humanos , Pessoa de Meia-Idade , Necrose , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pancreatite/patologia , Pancreatite/cirurgia , Estudos Prospectivos
15.
Eur J Radiol ; 13(1): 37-42, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1889427

RESUMO

Three dynamic computed tomographic methods used for staging of renal carcinoma in 70 patients are described and compared. Twenty-eight patients were examined using incremental dynamic scanning across the kidneys whilst infusing contrast via an arm vein (technique 1). Eighteen patients were staged using a single location dynamic scan sequence at the level of the renal hilum followed by an incremental sequence during an infusion of contrast into the femoral vein (technique 2). Twenty-four patients were examined using a single location sequence at the level of the renal veins and a rapid bolus incremental dynamic technique (technique 3). Technique 1 correctly staged 20 patients (72%) with 4 patients (14%) understaged and 4 (14%) overstaged, technique 2 correctly staged 11 (61%) patients with 3 (17%) overstaged and 4 (22%) understaged and technique 3 staged 17 (71%) correctly with 3 (13%) understaged and 4 (17%) overstaged. The techniques using single location scanning were more accurate in demonstrating tumour involvement of the renal vein and inferior vena cava but were less accurate in assessing extracapsular spread. Technique 3 was the most accurate in the diagnosis of lymph-node involvement. As accurate pre-operative knowledge of vascular involvement by tumour is more important to the surgeon than the presence of extracapsular spread, the combined single location and incremental scan technique is advocated.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X/métodos , Carcinoma de Células Renais/diagnóstico por imagem , Humanos , Iopamidol , Córtex Renal/diagnóstico por imagem , Córtex Renal/patologia , Medula Renal/diagnóstico por imagem , Medula Renal/patologia , Neoplasias Renais/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos , Veias Renais/diagnóstico por imagem , Veias Renais/patologia , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/patologia
16.
Environ Health Perspect ; 92: 127-30, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1935841

RESUMO

Heavy metals that contaminate soils and water usually exist in various oxidation states and form a number of compounds with different physical and chemical characteristics. These differences are often reflected in dramatic variation in toxicokinetic and biologic properties. Such variation in properties, critical in determining intrinsic toxicity, often causes a great deal of uncertainty in analyses of public health risks at sites where metal exposure is evaluated. In the Superfund program, such uncertainties may substantially undermine attempts to characterize potential impacts to populations exposed to metals from improperly disposed waste. In the case of chromium, risk assessment uncertainties can be considerable and fall generally into two categories. First, there is almost no information on potential health effects due to chronic oral exposure to chromium-containing compounds, and a nonquantifiable and probably large uncertainty exists in establishing no-effect levels. In fact, reference doses (RfDs) for CrIII and CrVI are based on chronic studies in which no adverse effects were seen even at the highest dose. Considerations of bioavailability, deduced from site characterization data, and acute toxicity indicate that general application of these RfDs may lead to highly inaccurate estimations of risk. Second, because of the ready reduction of CrVI in biological systems, it has not been possible to separate effects of CrVI from those of CrIII. Thus, data on the relative toxicity and carcinogenicity of these two species is sparse and difficult to interpret. Moreover, kinetic considerations make it difficult to determine the site and rates of reduction of CrVI. This makes prediction of target site concentrations of the two species difficult.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Carcinógenos Ambientais/efeitos adversos , Cromo/efeitos adversos , Resíduos Perigosos/economia , Administração Oral , Animais , Cromo/administração & dosagem , Cromo/farmacocinética , Humanos , Fatores de Risco , Solubilidade
18.
Mutat Res ; 216(1): 27-33, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2645513

RESUMO

Azide mutagenicity in susceptible non-mammalian systems involves the requisite formation of L-azidoalanine, a novel mutagenic amino acid. The biochemical mechanism(s) of azidoalanine-induced mutagenesis, however, is not known. Previous studies of the structural requirements for azidoalanine mutagenicity suggested the importance of free L-amino acid character, and that bioactivation of azidoalanine to the ultimate mutagenic species is required. To gain more insight into possible enzymatic processing, the alpha-methyl analogue, alpha-methyl-azidoalanine, and the homologue, 2-amino-4-azidobutanoic acid, were synthesized and tested for mutagenic potency in Salmonella typhimurium strain TA1530. In addition, azidoacetic acid, a possible azidoalanine metabolite, was prepared and tested. The results show that alpha-methyl substitution effectively blocks the mutagenic effects of azidoalanine with alpha-methyl-azidoalanine being nearly devoid of mutagenic activity. In contrast, homologation of azidoalanine to yield 2-amino-4-azidobutanoic acid produces a marked increase in molar mutagenic potency. As with azidoalanine, the mutagenic activity of this homologue is associated with the L-isomer. Azidoacetic acid, however, was only very weakly mutagenic when tested as either the free acid or ethyl ester. This low mutagenic potency may indicate that bioactivation does not involve the entry of azide-containing azidoalanine catabolite into the Kreb's cycle. The high potency of 2-amino-4-azidobutanoic acid may be indicative of more efficient bioactivation and/or greater intrinsic activity. Importantly, the latter finding clearly shows that potent azido-amino acid mutagenicity is not limited to azidoalanine alone.


Assuntos
Alanina/análogos & derivados , Azidas/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Acetatos/toxicidade , Alanina/toxicidade , Fenômenos Químicos , Química , Ciclo do Ácido Cítrico , Cisteína/farmacologia , Metilação , Testes de Mutagenicidade , Relação Estrutura-Atividade
20.
Mutat Res ; 177(1): 27-33, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3547101

RESUMO

Azide is metabolized to the proximate mutagen, L-azidoalanine in bacterial systems. While this novel mutagenic metabolite plays a key role in azide mutagenesis, the biochemistry of this role is unknown. The chemical synthesis of authentic racemic azidoalanine and several derivatives thereof allowed the exploration of structure-activity relationships with this unique mutagen. We found that whereas azide, azidoalanine and azidoalanine tert.-butyl ester were of comparable mutagenic potency, derivatives which lack the free amino group, such as azidopropionic acid and amino-blocked azidoalanine, were orders of magnitude less active. These findings demonstrate that the free amino group is essential for significant activity, while the carboxyl group may be less important. This conclusion together with the finding that DL-azidoalanine is a less potent mutagen than azide itself, suggests that the metabolite, while necessary for azide mutagenicity, may not be the ultimate mutagenic species. Instead, the data are consistent with the hypothesis that azidoalanine requires further bioactivation.


Assuntos
Alanina/análogos & derivados , Azidas/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Alanina/síntese química , Alanina/farmacologia , Azidas/síntese química , Testes de Mutagenicidade , Azida Sódica , Estereoisomerismo , Relação Estrutura-Atividade
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