Effect of cyclooxygenase inhibitors on the CRH-induced pituitary-adrenocortical activity during crowding stress. (25/286)

The aim of the present study was to determine the effect of social stress and significance of prostaglandins (PG) generated by constitutive and inducible cyclooxygenase (COX-1 and COX-2) in the stimulation of hypothalamic-pituitary-adrenal (HPA) axis by corticotropin releasing hormone (CRH) under basal and social crowding stress conditions. The stressed rats were crowded in groups of 24 to a cage for 3 or 7 days, whereas the control animals were haused in groups of 7 to a cage of the same size. The activity of HPA axis was determined by measuring plasma ACTH and serum corticosterone levels 1 h after i.p. CRH administration. Inhibitors of COX-1, piroxicam (0.2, 2.0, and 5.0 mg/kg), and COX-2, compound NS-398 (0.2 and 2.0 mg/kg), were administered i.p. 15 min prior to CRH (0.1 microg/kg i.p.) to control or crowded rats. The obtained results indicate that social stress for 3 and 7 days markedly intensifies the stimulatory action of CRH on ACTH secretion. Neither piroxicam nor NS-398 induce any significant effect on the CRH-elicited ACTH and corticosterone secretion in non-stressed or crowded rats. Therefore, PG generated by COX-1 or COX-2 do not participate to a significant extent in the stimulation of HPA axis by CRH under either basal conditions or during crowding stress. These results also indicate that the stimulatory action of CRH on ACTH secretion is not only completely resistant to desensitization but is sensitized during social crowding stress. The results contrast with a significant involvement of PG in the vasopressin-induced stimulation of HPA response during crowding stress.  (+info)

Severe endemic trachoma in Tunisia. (26/286)

In two villages in southern Tunisia where trachoma was endemic 7 per cent and 14 per cent of adults respectively had visual acuity of 20/400 or less. In both villages active trachoma affected most children under the age of two, reached a peak in two- to five-year-olds, then declined to age 15. The chronic inflammatory disease in childhood appeared to produce irreversible scarring of the eyelids, and loss of vision occurred in adult life due to corneal scarring caused by inturned eye lashes and loss of tears (dry-eyed syndrome). Economic development in one village was associated with a decline in active, infectious disease. In the second village, whose traditional economy was unchanged, there was the same prevalence of active disease over a three-year period. Unless economic development or public health control programmes reduce the prevalence of severe and moderate trachoma children now affected will develop the same blinding lesions as their parents. With the increasing numbers of children who survive there will probably be a dramatic increase in the numbers of the blind from trachoma in 10 to 20 years. Since active inflammatory trachoma in childhood responds to tetracyclines, erythromycin, and sulphonamides the disease should be attacked in those undeveloped rural areas where it continues to lead to blindness.  (+info)

Rethinking the socioeconomics and geography of tuberculosis among foreign-born residents of New Jersey, 1994-1999. (27/286)

OBJECTIVES: This study investigated the socioeconomic profile of foreign-born tuberculosis patients in New Jersey. METHODS: Foreign- and US-born tuberculosis patients in 1994-1999 were compared using various measures of socioeconomic status. RESULTS: Out of 4295 tuberculosis patients, 2005 (47%) were foreign-born. Foreign-born patients resided in more affluent, more educated, and less crowded areas than did US-born patients (P <.005). They were also more likely to have been employed during the 2 years before diagnosis (62% vs 41%, P <.001). Private physicians treated the majority of South Asian-born patients. CONCLUSIONS: Substantial numbers of employed foreign-born tuberculosis patients now reside in affluent New Jersey locations. Changes in tuberculosis control programs may be required when the socioeconomic status and place of residence of foreign-born populations diverge from traditional assumptions linking poverty with tuberculosis.  (+info)

Effect of cyclooxygenase inhibitors on the vasopressin induced ACTH and corticosterone response during crowding stress. (28/286)

The aim of the present study was to compare the effect of social stress on the corticotropin releasing hormone (CRH) and arginine vasopressin (AVP)-induced pituitary-adrenocortical activity. Also the significance of prostaglandins (PG) generated by constitutive and inducible cyclooxygenase (COX-1 and COX-2) in the stimulation of hypothalamic-pituitary-adrenal (HPA) axis by AVP under basal and crowding stress conditions was investigated. The control rats were housed 7 in a standard cage and stressed rats were crowded 24 in a cage of the same size during 7 days. The activity of HPA axis was determined by measuring plasma ACTH and serum corticosterone levels 1 h after i.p. AVP administration. Indomethacin (2.0 mg/kg i.p.), a non-selective COX inhibitor, piroxicam (0.2, 2.0, and 5.0 mg/kg), a more potent COX-1 than COX-2 inhibitor, and compound NS-398 (0.2 and 2.0 mg/kg) a selective COX-2 inhibitor, were administered i.p. 15 min prior to AVP (5.0 microg/kg i.p.) to control or crowded rats. The obtained results indicate that social stress for 7 days considerably inhibits the stimulatory action of AVP on ACTH secretion, while it intensifies the CRH-induced ACTH secretion. Indomethacin, piroxicam and NS-398 significantly diminished the AVP-elicited ACTH and corticosterone secretion in non-stressed rats. None of these COX antagonist induced any significant inhibition of the AVP-induced ACTH and corticosterone secretion in stressed rats. Therefore, PG generated by COX-1 or COX-2 do not participate to a significant extent in the HPA stimulation by AVP during crowding stress. These results suggest that social crowding stress desensitizes the PG stimulatory mechanism which considerably mediates the AVP-induced HPA stimulation under basal conditions. The results contrast with a lack of any involvement of PG in the CRH-induced stimulation of HPA response under basal or crowding stress conditions.  (+info)

Emergency department overcrowding in the United States: an emerging threat to patient safety and public health. (29/286)

Numerous reports have questioned the ability of United States emergency departments to handle the increasing demand for emergency services. Emergency department (ED) overcrowding is widespread in US cities and has reportedly reached crisis proportions. The purpose of this review is to describe how ED overcrowding threatens patient safety and public health, and to explore the complex causes and potential solutions for the overcrowding crisis. A review of the literature from 1990 to 2002 identified by a search of the Medline database was performed. Additional sources were selected from the references of the articles identified. There were four key findings. (1) The ED is a vital component of America's health care "safety net". (2) Overcrowding in ED treatment areas threatens public health by compromising patient safety and jeopardising the reliability of the entire US emergency care system. (3) Although the causes of ED overcrowding are complex, the main cause is inadequate inpatient capacity for a patient population with an increasing severity of illness. (4) Potential solutions for ED overcrowding will require multidisciplinary system-wide support.  (+info)

Appropriateness of emergency department visits in a Turkish university hospital. (30/286)

AIM: To determine the patterns and appropriateness of patients' use of a university hospital emergency department. METHODS: During a 14-day period in November 1998, we collected demographic and socio-economic data, reasons for preferring emergency department care, and patient visit data from consecutive patients visiting our tertiary-care university hospital emergency department. The principle investigator reviewed the study information forms and classified visits according to the classification of Afilalo into three categories: category I--emergent emergency department visits; category II--needing evaluation within 6 hours, either in emergency department or elsewhere; or category III--needing evaluation after more than 6 hours. Three emergency medicine residency-trained physicians determined the appropriateness of emergency department evaluation. Patients in the categories II and III were retrospectively reclassified as appropriate or inappropriate, according to availability of care at the outpatient facility at the hour of initial emergency department presentation. RESULTS: Complete data were collected from 1,155 (96.2%) of 1,201 patients visiting our emergency department during the study period. There were 69% (n=795) appropriate of visits. The mean stay at emergency department of inappropriate users lasted 66 min. The main reasons of inappropriate users to prefer emergency department care were its proximity, satisfaction with care, worsening symptoms, and unavailability of care in a regular clinic. CONCLUSION: Although inappropriate emergency department usage was high, these patients had relatively short emergency department stays. The impact on emergency department resource utilization and "over-crowding" by these patients may not be as great as commonly perceived.  (+info)

Repeated handling, restraint, or chronic crowding impair the hypothalamic-pituitary-adrenocortical response to acute restraint stress. (31/286)

The purpose of the present study was to assess whether, and to what extent prior handling, restraint or social crowding stress during 3-10 days affects the hypothalamic-pituitary-adrenocortical (HPA) response to an acute short-lasting restraint stress. Also the effect of a feedback inhibitory mechanism of corticosterone in the impairment of HPA axis by these stressors was investigated. Male Wistar rats were pretreated with handling 1 min/day for 3-10 days, restraint 2 times daily for 3-7 days and crowding stress for 7 days before exposure to acute restraint stress in metal tubes for 10 min. Some group of rats received exogenous s.c. corticosterone either once 25 mg/kg or 2 times daily 10 mg/kg for 3-10 days before restraint stress. After the last restraint the rats were decapitated and their trunk blood was collected for the measurement of plasma ACTH and serum corticosterone levels. Handling for 3-7 days, restraint for 3-7 days, and crowding for 7 days and a single pretreatment with corticosterone--all significantly and to a similar extent inhibited the restraint stress-induced increase in ACTH and corticosterone secretion. Chronic pretreatment with corticosterone blunted the restraint stress-induced increase in HPA axis activity. These results indicate that repeated short-lasting stress induced by handling, restraint, or crowding potently attenuates the acute restraint stress-induced stimulatory action of the HPA axis. They also indicate adaptive action of moderate stress on the HPA axis response to acute stress. The results also suggest that a short-lasting hypersecretion of corticosterone during psychological stress may induce a prolonged feedback inhibition of the HPA axis activity. The attenuation of HPA axis response by prior handling has also obvious methodological implications.  (+info)

Do risk factors for childhood infections and malnutrition protect against asthma? A study of Brazilian male adolescents. (32/286)

OBJECTIVES: We studied the association between early life conditions and asthma in adolescence. METHODS: We conducted a population-based birth cohort study involving 2250 male 18-year-olds residing in Brazil. RESULTS: Approximately 18% of the adolescents reported having asthma. Several childhood factors were found to be significantly associated with increased asthma risk: being of high socioeconomic status, living in an uncrowded household, and children being breastfed for 9 months or longer. CONCLUSIONS: The present results are consistent with the "hygiene hypothesis," according to which early exposure to infections provides protection against asthma. The policy implications of our findings are unclear given that risk factors for asthma protect against serious childhood diseases in developing countries.  (+info)