RESUMO
BACKGROUND: This study examined short-term efficacy, side effects and acceptability of a placebo treatment procedure designed to maintain children with attention deficit hyperactivity disorder (ADHD) on 50% of their usual stimulant dose. METHODS: An open-label prospective crossover trial was conducted in 26 children with ADHD, ages 7-15 years, stable on stimulant therapy, followed at a community-based developmental paediatrics ADHD clinic. Subjects were randomly assigned to one of two orders of experimental conditions: (1) baseline (100%) dose (1 week), then 50% dose (1 week), then 50% dose + placebo (1 week), or (2) baseline (100%), then 50% dose + placebo, then 50% dose. The inert nature of the placebo was fully disclosed to parent and child. Treatment was open-label for child, parents and physician, but single blind for teachers. Main outcome measures included weekly IOWA Conners parent and teacher rating scales, the Pittsburgh side effects rating scale (PSERS) and the Clinical Global Impressions (CGI) scale. RESULTS: Parent IOWA showed ADHD behaviour tended to remain the same when the dose of stimulant medication was reduced with placebo but to deteriorate when the dose was reduced without placebo. There were no significant differences between conditions on the Teacher IOWA. PSERS scores were higher at baseline than on 50% dose. On the CGI, there was a significant difference (P = 0.004) between the 50% dose and the 50% + placebo conditions. Individual subject analysis showed that eight subjects met criteria for responder. CONCLUSIONS: Results indicate that the open-label placebo treatment was acceptable and efficacious in the short term for some children.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Metilfenidato/uso terapêutico , Placebos/uso terapêutico , Adolescente , Criança , Estudos Cross-Over , Preparações de Ação Retardada/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Satisfação do Paciente , Projetos Piloto , Efeito Placebo , Estudos ProspectivosRESUMO
This statement reviews patterning as a treatment for children with neurologic impairments. This treatment is based on an outmoded and oversimplified theory of brain development. Current information does not support the claims of proponents that this treatment is efficacious, and its use continues to be unwarranted.
Assuntos
Terapia Comportamental , Lesão Encefálica Crônica/terapia , Deficiência Intelectual/terapia , Criança , HumanosRESUMO
Care coordination is a process that links children with special health care needs and their families to services and resources in a coordinated effort to maximize the potential of the children and provide them with optimal health care. Care coordination often is complicated because there is no single entry point to multiple systems of care, and complex criteria determine the availability of funding and services among public and private payers. Economic and sociocultural barriers to coordination of care exist and affect families and health care professionals. In their important role of providing a medical home for all children, primary care pediatricians have a vital role in the process of care coordination, in concert with the family.
Assuntos
Administração de Caso/organização & administração , Serviços de Saúde da Criança/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Pessoas com Deficiência , Pediatria , Criança , Humanos , Relações Profissional-Família , Encaminhamento e Consulta , Estados UnidosRESUMO
Acidification of the gastric cardia has been shown to increase lower esophageal sphincter pressure (LESP). The mechanism by which this phenomenon occurs remains unknown. This study was undertaken to examine the effect and mechanism of action of proximal gastric acidification on LESP in the dog model. In long-term studies, acidification resulted in a significant increase in mean LESP (23.2 cm H2O). Pretreatment with either topical lidocaine or subcutaneous atropine blocked the sphincteric response to acidification. Neither truncal vagotomy and pyloroplasty, proximal gastric vagotomy, antral vagotomy and pyloroplasty, nor circumferential gastric myotomy significantly altered the sphincteric response to acid. Pretreatment with 6-hydroxydopamine or somatostatin also failed to alter the increase in LESP in response to acid. In short-term studies, after gastric transection 5 cm distal to the gastroesophageal junction, acidification of a vagally innervated distal gastric pouch produced a slight decrease in LESP, whereas acidification of the proximal (orad) section of gastric mucosa still resulted in a significant increase in LESP. These studies suggest that the increase in LESP observed with acidification of the gastric cardia is a local mechanism mediated by an intrinsic neural pathway dependent on cholinergic neurotransmission. This phenomenon of local reflex excitation may be another contributing mechanism to the barrier against gastroesophageal reflux.
Assuntos
Junção Esofagogástrica/fisiologia , Ácido Clorídrico/farmacologia , Animais , Fenômenos Biomecânicos , Denervação , Cães , Junção Esofagogástrica/efeitos dos fármacos , Antagonistas de Hormônios/farmacologia , Mucosa Intestinal/metabolismo , Sistema Nervoso Parassimpático , Pressão , Estômago/inervação , Estômago/fisiologia , Fatores de TempoRESUMO
BACKGROUND: An increase in esophageal mucosal blood flow (MBF) may be an important protective mechanism against mucosal injury from noxious agents that are ingested or refluxed. This study investigated the changes in MBF and the regulation thereof after intraluminal application of noxious chemical stimuli. The role, if any, of substance P (SP) and nitric oxide (NO), two potent vasodilatory substances, and the vascular distribution of SP in the distal esophagus were evaluated. METHODS: Esophageal MBF was measured in anesthetized dogs with a laser Doppler flow probe attached to manometry and pH probes. MBF was measured before and after topical application of HCl (2 ml; 1N) or capsaicin (2 ml; 0.5%) in the distal esophagus. The effects on MBF of intraarterial SP and bradykinin were also determined. Pharmacologic antagonists and denervation procedures were used to delineate the mechanisms that regulate MBF. RESULTS: Sequential luminal applications of hydrochloric acid (HCl) or a single application of capsaicin increased MBF (p < 0.01). Topical intraluminal lidocaine blocked the response to capsaicin (p > 0.2) but not to HCl (p < 0.05). Abrupt increases in MBF occurred with intraarterial SP or bradykinin (p < 0.01). Neither atropine nor truncal vagotomy blocked the increase in MBF from these peptides or noxious stimuli. The NO synthesis antagonist NG-nitro-L-arginine methyl ester (L-NAME) blocked the response to bradykinin and attenuated the response to HCl (p < 0.05). NG-nitro-L-arginine methyl ester did not affect the response to SP or capsaicin. A substance P antagonist blocked the effects of both capsaicin (p > 0.6) and SP (p > 0.1) but not that of HCl (p < 0.01) or bradykinin (p > 0.01). CONCLUSIONS: Intraluminal applications of HCl or capsaicin appear to stimulate increases in esophageal MBF by different mechanisms. HCl produces an adaptive response that appears dependent on the paracrine effect of NO. Capsaicin-sensitive neurons mediate vasodilation through SP neurotransmission, independent of extrinsic vagal or cholinergic innervation.
Assuntos
Esôfago/irrigação sanguínea , Óxido Nítrico/metabolismo , Substância P/fisiologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Cães , Ácido Clorídrico/farmacologia , Imuno-Histoquímica , Lidocaína/farmacologia , NG-Nitroarginina Metil Éster , Fluxo Sanguíneo Regional/efeitos dos fármacos , VagotomiaRESUMO
Lower esophageal sphincter (LES) effects produced by the mammalian tachykinins were evaluated in anesthetized dogs. The distribution and content of substance P (SP) and neurokinin A (NKA) in the region of the canine gastroesophageal junction was also studied. SP and NKA stimulated a linear dose-dependent contraction of the LES after intra-arterial administration. Neurokinin B (NKB) failed to stimulate an increase in LES pressure (LESP). SP was characterized by an immediate but short-lived contraction followed by a period of relaxation. NKA stimulated a potent LES contraction that was slow in onset but long-lasting. On an equimolar basis, both SP and NKA were approximately 100 times more potent LES stimulants than bethanechol or phenylephrine. Pretreatment with atropine (muscarinic blockade) or tetrodotoxin (neural blockade) inhibited the effect produced by SP. NKA appeared to stimulate LES contraction independent of neural or cholinergic mechanisms. Radioimmunoassay revealed a regional variation in tachykinin content in the gastroesophageal junction. Ganglia, cell bodies, nerve fascicles, and neurites stained specifically for both SP and NKA. The variable effects, potencies, and mechanisms of action observed in this study suggest the presence of specific tachykinin receptor subtypes in the gastroesophageal junction. Both SP and NKA were found to have a broad neural distribution in this region. These findings suggest that the tachykinins may play an important role in neuroregulation of LES smooth muscle.
Assuntos
Junção Esofagogástrica/fisiologia , Taquicininas/fisiologia , Animais , Atropina/farmacologia , Cromatografia Líquida de Alta Pressão , Cães , Relação Dose-Resposta a Droga , Junção Esofagogástrica/efeitos dos fármacos , Junção Esofagogástrica/inervação , Junção Esofagogástrica/metabolismo , Esôfago/metabolismo , Mucosa Gástrica/metabolismo , Imuno-Histoquímica , Manometria , Contração Muscular/efeitos dos fármacos , Neurocinina A/metabolismo , Neurocinina A/farmacologia , Neurocinina A/fisiologia , Neurocinina B/metabolismo , Neurocinina B/farmacologia , Neurocinina B/fisiologia , Neurônios/metabolismo , Fentolamina/farmacologia , Radioimunoensaio , Substância P/metabolismo , Substância P/farmacologia , Substância P/fisiologia , Taquicininas/metabolismo , Tetrodotoxina/farmacologiaRESUMO
Distal esophageal sensory nerves were stimulated in 17 anesthetized dogs divided into three age groups to determine the laryngeal, cardiovascular, and respiratory effects. Group I puppies were 5 to 6 weeks of age, group II puppies were 8 to 19 weeks of age, and group III animals were adult dogs. Marked laryngeal adductor activity and laryngospasm were observed in group II puppies, while no or minimal laryngeal adduction was seen in younger puppies and adult dogs. Mean arterial pressure and heart rate increased significantly in groups II and III (P < .005) but remained unchanged in group I animals (P > .4). This response is distinctly different from the laryngeal chemoreflex because central apnea, hypotension, and bradycardia were absent. The afferent limb of the response is mediated by the vagus nerve as bilateral transthoracic truncal vagotomy eliminated the reflex. The laryngeal response observed following stimulation of distal esophageal afferent fibers may be important in the mechanism of apparent life-threatening events (ALTEs) and the sudden infant death syndrome (SIDS) associated with gastroesophageal reflux disease.
Assuntos
Envelhecimento/fisiologia , Esôfago/inervação , Laringismo/etiologia , Neurônios Aferentes/fisiologia , Reflexo/fisiologia , Vias Aferentes/fisiologia , Animais , Pressão Sanguínea/fisiologia , Capsaicina/farmacologia , Cães , Eletromiografia , Refluxo Gastroesofágico/complicações , Frequência Cardíaca/fisiologia , Humanos , Lactente , Laringismo/fisiopatologia , Neurônios Aferentes/efeitos dos fármacos , Estimulação Química , Morte Súbita do Lactente/etiologia , Vagotomia Troncular , Nervo Vago/fisiologiaRESUMO
The laryngeal chemoreflex (LCR) is characterized by mixed apnea and cardiovascular instability and is elicited by applying water to the laryngeal mucosa of developing animals. The LCR may be fatal in very young animals, and the reflex has been postulated as a possible mechanism of sudden infant death syndrome. Several antagonists have been found to alter the severity of the LCR, but the primary neurotransmitters involved in mediating the reflex response are not yet well understood. This study investigates the effect, on the LCR, of the pharmacologic antagonism of calcitonin gene-related peptide (alphaCGRP), a neurochemical found in abundance in the mammalian laryngeal mucosa and its innervating system. The LCR was elicited in 10 mixed breed piglets, 17.7 days of age (12 to 22 days), before and during infusion of alphaCGRP 8-37, a pharmacologic inhibitor of alphaCGRP, and cardiorespiratory and laryngeal responses were compared. The duration of obstructive apnea decreased from 17.9 to 9. 8 seconds (P < 0.03) in the presence of alphaCGRP 8-37. Mean central apnea did not change for the group (P > 0.05), although it was completely inhibited in 2 animals. Cardiovascular changes were not significantly altered by the alphaCGRP inhibitor. alphaCGRP appears to play a regulatory role in the apneic response of the LCR, particularly its obstructive component, but not the cardiovascular response.
Assuntos
Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Laringe/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Reflexo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Infusões Intravenosas , Laringe/fisiologia , Síndromes da Apneia do Sono/fisiopatologia , SuínosRESUMO
A comprehensive sexuality questionnaire was administered to 37 females, ages 13 through 16 years, who attended clinics for routine health care. Subjects completed standardized scales of self-concept, locus of control, and future orientation. They also were given a short battery of standardized cognitive tests. Three groups were identified: Group 1 was sexually active and using contraception reliably, Group 2 was not using contraception reliably, and Group 3 had not been sexually active. Group 1 adolescents had higher scores on the vocabulary subtest of the WISC-R (F = 3.4, p less than .05) than did Group 2 adolescents, over and above the effect of socioeconomic status (SES). Group 1 subjects had higher scores on knowledge of sex and contraception than did Group 2 (F = 3.3, p less than .05). Group 1 had more internal locus of control (F = 7.0, p less than .005) than did Group 2 over and above the effect of SES. Mean scores for Group 3 adolescents were intermediate and not significantly different. The findings suggest that cognitive factors may influence contraceptive behavior in adolescent females.
PIP: Comprehensive sexuality questionnaires were given to 37 adolescent females to identify cognitive and personality factors potentially influencing decision making about sexual activity and contraceptive use. Subjects were aged 13-16 years, attending clinics for routine health care, and of primarily low socioeconomic status (SES). 54% of the sample was White, 41% Black, and 5% Hispanic, with 81% residing in urban or suburban settings. The sample was divided into 3 groups on the basis of respondent information obtained in standardized scales of self-concept, locus of control, future orientation, and cognitive tests. 13 were in group 1, 12 in group 2, and 12 in group 3. Adolescents in group 1 were sexually active and using contraception reliably, group 2 was sexually active and not using contraception reliably, and group 3 had not been sexually active. Group 1 scored higher than group 2 on knowledge of sex and contraception, on the vocabulary subtest of Wechsler Intelligence Scales for Children, and had more internal locus of control. The latter two effects were independent of SES. These results, therefore, suggest that cognitive factors may influence contraceptive behavior in adolescent females.
Assuntos
Tomada de Decisões , Conhecimentos, Atitudes e Prática em Saúde , Gravidez na Adolescência/psicologia , Resolução de Problemas , Comportamento Sexual , Adolescente , Feminino , Humanos , Inteligência , Gravidez , Meio SocialRESUMO
This study investigated patterns of neurodevelopmental dysfunction in children with writing disorders (WD). Records of children, ages 9 to 15 years, referred to a school problems clinic were examined. Using teacher questionnaire information, including ratings of writing legibility, mechanics, rate, linguistic sophistication, and spelling, 99 cases of WD were found. Sixty-three children without WD served as clinic controls. A cluster analysis revealed four discrete subtypes of WD and two non-WD control clusters. The four WD clusters were found to have different patterns of writing and reading characteristics. Neurodevelopmental tests discriminated among the clusters (F = 2.8, p less than .0001), and an examination of neurodevelopmental performance characteristics among the clusters showed different patterns of strengths and weaknesses. An empirically derived subtyping of WD is proposed: WD with fine motor and linguistic deficits, WD with visual-spatial deficits, WD with attention and memory deficits, and WD with sequencing deficits. This subtyping, if confirmed in a population study, may have important diagnostic and therapeutic implications.
Assuntos
Agrafia/diagnóstico , Escrita Manual , Deficiências da Aprendizagem/diagnóstico , Logro , Adolescente , Agrafia/psicologia , Agrafia/reabilitação , Apraxias/diagnóstico , Apraxias/psicologia , Apraxias/reabilitação , Atenção , Criança , Feminino , Humanos , Inteligência , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/psicologia , Transtornos do Desenvolvimento da Linguagem/reabilitação , Deficiências da Aprendizagem/psicologia , Deficiências da Aprendizagem/reabilitação , Masculino , Rememoração Mental , Destreza Motora , Testes Neuropsicológicos , Desempenho PsicomotorRESUMO
The usual treatment for biliary atresia is a Kasai procedure followed by liver transplantation when indicated. Although primary transplantation for biliary atresia without a previous Kasai procedure is occasionally advocated, it is rarely performed. This review was undertaken to evaluate the impact of a Kasai procedure on the morbidity and mortality of patients who went on to need a liver transplant. Sixty-three patients with biliary atresia were included in this review. Fifty seven patients underwent transplantation: eight patients had a liver transplant only (group 1), and 49 patients underwent a Kasai procedure before transplantation (group 2). Six patients died before receiving a transplant. Time spent on the waiting list for liver transplant was longer in group 2 than in group 1 (170.3 +/- 24.6 days versus 63.3 +/- 7.1 days, P < .05). The patients in group 1 were younger (0.7 +/- 0.2 versus 2.3 +/- 0.4 years) and smaller (6.9 +/- 0.4 kg versus 11.6 +/- 1.2 kg) than the patients in group 2 (P = .07). There was no difference in pretransplant urgency status between the two groups. The mean duration of the transplant operation was shorter in group 1 patients (476.8 +/- 53.3 minutes) compared with group 2 (593.9 +/- 29.3 minutes, P = .06). Group 1 patients received 199.8 +/- 46.2 mL/kg blood transfusion intraoperatively, and group 2 patients had twice that amount, 466 +/- 122.5 mL/kg. No patients in group 1 experienced postoperative bowel perforations or required reoperation for bleeding. In group 2 however, 11 of 49 (22.4%) experienced bowel perforations and 7 of 49 (14.2%) required reoperation for bleeding. There was no difference in nonsurgical complications between the two groups. Long-term survival was equal in the 2 groups: six of eight patients (75%) in group 1 and 36 of 49 (74%) in group 2. The marked increase in complications noted in group 2 patients did not reach statistical significance because of the much smaller number of patients in group 1. These results suggest that patients with biliary atresia have fewer complications after transplantation if a Kasai procedure is not performed before the transplant, and that a more careful selection of surgical options available in treating patients with biliary atresia is required.
Assuntos
Atresia Biliar/cirurgia , Transplante de Fígado , Portoenterostomia Hepática/efeitos adversos , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Lactente , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Seleção de Pacientes , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
PURPOSE: The management of noncorrectable extra hepatic biliary atresia includes portoenterostomy, although the results of the surgery are variable. This study was done to develop criteria that could successfully predict the outcome of surgery based on preoperative data, including percutaneous liver biopsy, allowing a more selective approach to the care of these babies. METHODS: The charts and biopsy results of 31 patients who underwent a Kasai procedure for biliary atresia between 1984 and 1994 were reviewed. Values for preoperative albumin, bilirubin, age of patient at Kasai, and lowest postoperative bilirubin were recorded. Surgical success was defined as postoperative bilirubin that returned to normal. A pathologist blinded to the child's eventual outcome graded the pre-Kasai needle liver biopsy results according to duct proliferation, ductal plate lesion, bile in ducts, lobular inflammation, giant cells, syncitial giant cells, focal necrosis, bridging necrosis, hepatocyte ballooning, bile in zone 1, 2, and 3, cholangitis, and end-stage cirrhosis. Clinical outcome was then predicted. RESULTS: Success after portoenterostomy could not reliably be predicted based on gender, age at Kasai, preoperative bilirubin or albumin levels. Histological criteria, however, predicted outcome in 27 of 31 patients (P < .01). Fifteen of 17 clinical successes were correctly predicted; as were 12 of 14 clinical failures (sensitivity, 86%; specificity, 88%). Individually, the presence of syncitial giant cells, lobular inflammation, focal necrosis, bridging necrosis, and cholangitis, were each associated with failure of the portoenterostomy (P < .05). Bile in zone 1 was associated with clinical success of the procedure (P < .05). CONCLUSIONS: Based on the predictive information available in a liver biopsy, we conclude that those patients who will not benefit from a Kasai procedure can be identified preoperatively, and channeled immediately to transplantation.
Assuntos
Atresia Biliar/cirurgia , Fígado/patologia , Portoenterostomia Hepática , Atresia Biliar/patologia , Biópsia por Agulha , Feminino , Humanos , Lactente , Inflamação/patologia , Masculino , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Respiratory manifestations of gastroesophageal reflux disease (GERD) are being recognized with increasing frequency. We present the evaluation and management of four infants and children with unusual respiratory symptoms attributed to GERD. The advantages and disadvantages of diagnostic studies of GERD are discussed, and an evaluation and treatment protocol is presented. Treatment must be tailored to the nature and severity of the patient's presenting symptoms and includes conservative, pharmacologic, and/or surgical management.
Assuntos
Refluxo Gastroesofágico/complicações , Doenças Respiratórias/etiologia , Obstrução das Vias Respiratórias/etiologia , Apneia/etiologia , Bradicardia/etiologia , Tosse/etiologia , Feminino , Refluxo Gastroesofágico/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Pneumonia/etiologia , Insuficiência Respiratória/etiologiaRESUMO
Substance P (SP), a putative sensory neurotransmitter, mediates reflex laryngeal adductor activity in developing dogs. Such reflex activity includes life-threatening laryngospasm induced by stimulation of distal esophageal afferent nerves. The site of SP's activity is unknown. This research was undertaken to determine whether injection of SP into the nucleus tractus solitarius (NTS) of developing beagles alters laryngeal adductor motor activity. Six animals, 57 to 78 days of age, underwent stereotactic injection of 5 to 10 microL of SP into the region of the NTS, identified by electrical stimulation of the ipsilateral superior laryngeal nerve. In 8 additional studies, SP was injected into the cerebellum (2) or brain stem (6) distant from the NTS. Cardiovascular and electromyographic (EMG) responses of the diaphragm and the cricothyroid (CT) and/or thyroarytenoid (TA) muscles were recorded in all 6 animals. Injection of SP into the region of the NTS induced a decrease in blood pressure in all animals and an increase in either ipsilateral CT or TA activity. Three of these animals experienced mixed apnea characterized by sustained EMG activity (spasm) of the ipsilateral CT or TA muscles and an absence of diaphragm EMG activity. The apnea event was fatal in 1 of these animals. In the 6 animals who underwent injections in the brain stem but outside the region of the NTS, diaphragm and laryngeal EMG activity generally did not change after injection of SP, with the exception of 1 animal who experienced a mild, short-lived increase in ipsilateral CT activity. A brief phasic increase in ipsilateral CT activity was seen in both animals who underwent injection of SP into the cerebellum. A putative sensory neurotransmitter, SP evokes ipsilateral CT and/or TA EMG activity when injected into the region of the NTS in developing beagle dogs. This research suggests that SP in the NTS may play a role in mediating life-threatening laryngeal adductor reflexes in developing mammals and may provide important information regarding therapeutic intervention.
Assuntos
Músculos Laríngeos/efeitos dos fármacos , Músculos Laríngeos/crescimento & desenvolvimento , Laringismo/induzido quimicamente , Desenvolvimento Muscular , Núcleo Solitário/efeitos dos fármacos , Técnicas Estereotáxicas , Substância P/efeitos adversos , Substância P/fisiologia , Fatores Etários , Animais , Modelos Animais de Doenças , Cães , Eletromiografia , Humanos , Recém-Nascido , Laringismo/diagnóstico , Laringismo/fisiopatologia , Atividade Motora/efeitos dos fármacos , Técnicas Estereotáxicas/instrumentação , Substância P/administração & dosagem , Morte Súbita do Lactente/etiologiaRESUMO
Reflex laryngeal adduction is a component of both the laryngeal chemoreflex and the esophagolaryngeal adductor reflex, two life-threatening reflexes that occur in immature animals. These two reflex responses are also thought to exist in infants and may play a role in causing life-threatening laryngospastic events and perhaps sudden infant death syndrome. Identifying neurotransmitters that mediate laryngeal adduction is important to understanding the mechanism of reflex laryngeal responses and to identifying potential means of pharmacologic prevention. Substance P (SP), a tachykinin, putatively functions as a sensory neurotransmitter and may play a role in mediating laryngeal reflexes. Substance P-immunoreactive-like fibers and receptors are present in the subepithelial tissues of the larynx, the vagus nerves, the nodose and jugular ganglia, and the vagal brain stem nuclei. In this investigation, the effect of SP infusion on laryngeal motor activity in an in vivo model is reported. Substance P was infused intravenously into 8 puppies (20 to 133 days of age, mean 81.2), on a mean of 3.0 occasions (range 1 to 6). Cardiovascular, respiratory, arterial blood gas, and cricothyroid (CT), thyroarytenoid (TA), and genioglossus electromyographic (EMG) responses to infusion of the tachykinin were recorded and subsequently analyzed. The SP infusion induced a marked increase in CT or TA EMG activity in 23 of 24 studies, and the increase was typically apparent within 60 seconds of the infusion. An increase in genioglossus EMG activity did not occur. An immediate, profound decrease in mean arterial pressure and an increase in respiratory rate and depth of chest wall excursion accompanied the laryngeal response. Arterial blood gas values remained unchanged (p > .05). The laryngeal adductor response to SP infusion was blocked when animals were pretreated with a systemic SP antagonist (Pfizer CP-96,345). This study demonstrates that peripheral infusion of the tachykinin SP induces a marked increase in laryngeal adductor activity. The response may be blocked by pretreatment of animals with a systemic SP antagonist. Because SP is thought to act primarily as a sensory neurotransmitter, these findings may be important in understanding the mechanism of reflex laryngeal adductor responses.
Assuntos
Músculos Laríngeos/efeitos dos fármacos , Reflexo/efeitos dos fármacos , Substância P/farmacologia , Animais , Compostos de Bifenilo/farmacologia , Cães , Eletromiografia , Infusões Intravenosas , Músculos Laríngeos/fisiologia , Laringismo/fisiopatologia , Pré-Medicação , Substância P/administração & dosagem , Substância P/antagonistas & inibidores , Fatores de TempoRESUMO
The laryngeal chemoreflex (LCR) is a potentially life-threatening reflex that is elicited in immature animals by the topical application of water to the laryngeal mucosa. The reflex response is characterized by immediate apnea and laryngeal adduction and delayed cardiovascular instability. The cardiorespiratory changes of the LCR may be life-threatening, particularly in very immature animals such as piglets under 2 weeks of age. The afferent and efferent limbs of the LCR are mediated through the vagus nerve, but the neuromediators responsible for the reflex changes have not yet been clearly elucidated. Previous agonist and antagonist studies in immature dogs demonstrated that substance P, a sensory tachykinin, mediates the life-threatening esophagolaryngeal adductor reflex elicited by distal esophageal sensory nerve stimulation. This study was conducted to determine if substance P also plays a role in mediating the LCR. The LCR response was compared before and after treatment with intravenous substance P antagonist (Pfizer CP-96,345-1) in eight piglets (mean 27.7 days of age). The laryngeal and cardiovascular responses of the animals following intravenous administration of the tachykinins substance P, neurokinin A, and neurokinin B were also assessed. Pretreatment with substance P antagonist did not alter the LCR's duration of apnea (p > .10), laryngeal adductor response, or early change in mean arterial pressure (p > .10), although the early maximal heart rate response was significantly altered (p < .01). Intravenous substance P, neurokinin A, and neurokinin B did not reproduce the laryngeal respiratory response of the LCR. We conclude that substance P, neurokinin A, and neurokinin B are not key neurotransmitters of the LCR.
Assuntos
Células Quimiorreceptoras/efeitos dos fármacos , Laringe/efeitos dos fármacos , Reflexo/fisiologia , Substância P/efeitos adversos , Animais , Apneia/induzido quimicamente , Frequência Cardíaca/efeitos dos fármacos , SuínosRESUMO
Extended pH probe testing is often performed in patients believed to have extraesophageal symptoms of gastroesophageal reflux disease (GERD), although for this indication its diagnostic value is not well established. A retrospective review of all patients who underwent pH probe testing between 1994 and 1998 was conducted to determine the outcome of antireflux therapy in the subgroup with probable extraesophageal symptoms of GERD. Sixty-eight patients underwent antireflux therapy and had adequate follow-up after pH probe testing to be included in the study. Fifty-eight patients (85%) responded to antireflux therapy (improved, 44%; cured, 41%). The positive predictive value of distal pH probe testing was greater than 90%, but the negative predictive value was less than 50%. The reproducibility of pH probe testing on different study days was poor, but pH probe testing was helpful in assessing the adequacy of antireflux therapy. The presence of gastrointestinal symptoms did not correlate with the response of extraesophageal symptoms to antireflux therapy. Thirteen patients underwent double-probe pH studies. The mean percent time the pH was less than 4 in the upper esophagus was 2.6% (range, 1% to 9.6%). Twelve of these patients were improved or cured with antireflux therapy. Distal pH probe testing is of limited benefit in predicting whether patients with extraesophageal symptoms of GERD will respond to antireflux therapy. If extraesophageal symptoms of GERD are suspected, patients should undergo an empiric trial of antireflux therapy. Distal pH probe testing should be reserved for assessing the adequacy of antireflux therapy if symptoms persist. A prospective, randomized, controlled study will aid in determining the predictive value of double-probe pH studies in pediatric patients with probable extraesophageal symptoms of GERD.
Assuntos
Determinação da Acidez Gástrica/instrumentação , Refluxo Gastroesofágico/diagnóstico , Monitorização Ambulatorial/instrumentação , Otorrinolaringopatias/diagnóstico , Adolescente , Antiulcerosos/uso terapêutico , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Humanos , Lactente , Recém-Nascido , Masculino , Otorrinolaringopatias/tratamento farmacológico , Otorrinolaringopatias/etiologia , Inibidores da Bomba de Prótons , Resultado do TratamentoRESUMO
This paper describes an itinerant medical evaluation (IME) project and reports on the outcome of 108 consecutive referrals made in the first year. Subjects were of ages 5 to 17 years. Most students had been evaluated by the schools but were not receiving special education or related services. IME led to clinical diagnosis of ADHD in 70% of the sample, and specific learning disabilities were diagnosed in 26%. Several other clinically significant and educationally relevant diagnoses were made. As a result of the IME, many students were placed in special education and/or began to receive related services. At three-month follow-up, classroom accommodations were being made for 97% of the students. Teachers reported they felt more capable of teaching challenging students as a result of the IME. Significant improvements occurred in hyperactivity, conduct problems, and inattention, and grades improved in 31% of the sample. Reasons for the project's success are discussed.
Assuntos
Relações Interinstitucionais , Deficiências da Aprendizagem/reabilitação , Equipe de Assistência ao Paciente , Encaminhamento e Consulta/estatística & dados numéricos , Serviços de Saúde Escolar/organização & administração , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/reabilitação , Criança , Pré-Escolar , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Deficiências da Aprendizagem/diagnóstico , Masculino , Modelos Organizacionais , North Carolina , Projetos Piloto , Avaliação de Programas e Projetos de SaúdeRESUMO
30 normally achieving and 24 high school students with learning disabilities from one public high school were enrolled in an exploratory study of adolescents' perceptions of their learning difficulties. Adolescents completed a structured interview based on metacognitive and information-processing theories. Items on which subjects reported the most substantial problems related mainly to attention and organization. Comparison of the frequencies of endorsement of items for each group showed adolescents with learning disabilities most commonly reported problems with use of strategies, retrieval memory, and rapid processing. Current assessment methods and instructional approaches often ignore these crucial aspects of learning and productivity by high school students.
Assuntos
Escolaridade , Deficiências da Aprendizagem/psicologia , Autoimagem , Adaptação Psicológica , Adolescente , Feminino , Humanos , Inteligência , Masculino , Determinação da PersonalidadeRESUMO
The relationships between attention deficits, hyperactivity, neurodevelopmental performance, and problematic peer relationships were examined in 99 consecutive children (ages 9 to 11 years) referred for school problems to a clinic. Using a teachers' rating scale, 32 children with cognitive inattention and a comparison group of 67 children without cognitive inattention were identified. The former group comprised children who met criteria for Attention Deficit-Hyperactivity Disorder (ADHD). The latter group comprised children with learning disorders and school problems, 42 of whom did not meet criteria for ADHD. Analysis indicated that the study group had greater peer problems, as estimated by teachers' ratings, than the comparison group. Cognitive inattention was related to peer problems over and above the effects of hyperactivity. Neurodevelopmental predictors of peer problems were different among children with ADHD and those without ADHD. Among children with ADHD, proficiency in tasks of verbal fluency was significantly predictive of peer problems. These preliminary findings suggest that children showing teacher-rated cognitive inattention also manifest significant peer problems and that the presence of strong verbal fluency may make these children prone to inappropriate excessive talking and, subsequently, to alienation of peers.