Risky behavior in teens with cystic fibrosis or sickle cell disease: a multicenter study

OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens.     

Maternal predictors of early breast milk output

Previous attempts to show a quantitative relationship between maternal hormone levels and early milk output have used small sample sizes and simple correlations. Women of mixed parity and similar socio-economic status and education were recruited to a study using multivariate analysis to look for these associations. Hormone levels (oestradiol, progesterone, prolactin and thyrotropin (TSH)) were determined for 91 mothers at four time points (ante- and postnatally) from finger-prick blood spots by fluoro-immunoassay. Milk output at 1 and 4 weeks was determined from 24-h test weighings. Parity was found to be the most significant factor affecting breast milk volume at 1 wk postpartum (multiparous women delivered 142 ml more milk in 24 h than primiparous women). Total time spent feeding had a strong association with breast milk volume, with increasing time having a negative effect. Multiple regression analysis, controlling for parity and time spent feeding, showed a positive association of milk output at 1 wk with antenatal progesterone and antenatal prolactin levels. At 4 wk, higher postpartum oestradiol levels had a negative association and antenatal progesterone levels a positive association with milk output. This study demonstrates that there are quantitative associations between antenatal maternal hormone levels and breast milk output in the early postnatal period.     

Expression of adhesion molecules on CD34+ cells: CD34+ L-selectin+ cells predict a rapid platelet recovery after peripheral blood stem cell transplantation

Adhesion molecules play a role in the migration of hematopoietic progenitor cells and regulation of hematopoiesis. To study whether the mobilization process is associated with changes in expression of adhesion molecules, the expression of CD31, CD44, L-selectin, sialyl Lewisx, beta 1 integrins very late antigen 4 (VLA-4) and VLA-5, and beta 2 integrins lymphocyte function-associated 1 and Mac-1 was measured on either bone marrow (BM) CD34+ cells or on peripheral blood CD34+ cells mobilized with a combination of granulocyte colony- stimulating factor (G-CSF) and chemotherapy. beta 1 integrin VLA-4 was expressed at a significantly lower concentration on peripheral blood progenitor cells than on BM CD34+ cells, procured either during steady- state hematopoiesis or at the time of leukocytapheresis. No differences in the level of expression were found for the other adhesion molecules. To obtain insight in which adhesion molecules may participate in the homing of peripheral blood stem cells (PBSCs), the number of CD34+ cells expressing these adhesion molecules present in leukocytapheresis material was quantified and correlated with hematopoietic recovery after intensive chemotherapy in 27 patients. The number of CD34+ cells in the subset defined by L-selectin expression correlated significantly better with time to platelet recovery after PBSC transplantation (r = - .86) than did the total number of CD34+ cells (r = -.55). Statistical analysis of the relationship between the number of CD34+L-selectin+ cells and platelet recovery resulted in a threshold value for rapid platelet recovery of 2.1 x 10(6) CD34+ L-selectin+ cells/kg. A rapid platelet recovery (< or = 14 days) was observed in 13 of 15 patients who received > or = 2.1 x 10(6) CD34+ L-selectin+ cells/kg (median, 11 days; range, 7 to 16 days), whereas 10 of 12 patients who received less double positive cells had a relative slow platelet recovery (median, 20 days; range, 13 to 37 days). The L-selectin+ subpopulation of CD34+ cells also correlated better with time to neutrophil recovery (r = - .70) than did the total number of reinfused CD34+ cells (r = -.51). However, this latter difference failed to reach statistical significance. This study suggests that L-selectin is involved in the homing of CD34+ cells after PBSC transplantation.     

Behavior of plasminogen at the luminal surface of the normal and deendothelialized rabbit aorta in vivo and in vitro

The behavior of purified rabbit plasminogen at the luminal surface of the uninjured and deendothelialized rabbit aorta has been studied in vivo and in vitro. After intravenous injection, 125I-plasminogen associated rapidly with the endothelium (approximately 0.1 pmol/cm2 at saturation) and passed through to accumulate in the subendothelium. At two to 15 hours after injection, 11 to 15 times more radioactivity was associated with the subendothelium than with the endothelium. Removal of the endothelium by balloon catheter led to a rapid adsorption of 125I-plasminogen by the luminal surface of the vessel; saturation (9.1 pmol/cm2) was attained at ten to 20 minutes after deendothelialization. Of the adsorbed plasminogen (radioactivity), only 2% to 4% was associated with the adherent platelet monolayer. Uptake of 125I- plasminogen by the deendothelialized vessel was not significantly inhibited by epsilon-aminohexanoic acid whether injected before or after the 125I-plasminogen. No evidence of plasmin activity at the aorta surface was found from either transmission electron microscopy studies or from amidolytic assays of plasminogen-saturated deendothelialized aorta samples before or after urokinase treatment. Balloon catheter treatment in vivo, however, generated significant antiplasmin activity of the deendothelialized aorta surface. We conclude that plasmin formed in vivo is probably inactivated by the antiplasmin activity that is associated with the subendothelium.     

Planning for children whose parents are dying of HIV/AIDS. American Academy of Pediatrics. Committee on Pediatric AIDS, 1998-1999

Although the character of acquired immunodeficiency syndrome is changing into a chronic illness, it is estimated that by the end of this century, 80 000 children and adolescents in the United States will be orphaned by parental death caused by human immunodeficiency virus infection. Plans for these children need to be made to ensure not only a stable, consistent environment that provides love and nurturing, but also the medical and social interventions necessary to cope with the tragic loss. Pediatricians should become aware of local laws and community resources and initiate discussion early in the course of parental illness to facilitate planning for the future care and custody of the children. States need to adopt laws and regulations that provide flexible approaches to guardianship and placement of children orphaned by acquired immunodeficiency syndrome.     

Transverse cerebellar diameter on cranial ultrasound scan in preterm neonates in an Australian population

OBJECTIVE: Fetal measurement of transverse cerebellar diameter (TCD) has been shown to correlate well with gestational age (GA), even in the presence of growth retardation. The aim of this study was to define the normal range of TCD in preterm neonates in an Australian population between 23 and 32 weeks GA. METHODOLOGY: Infants admitted to the Royal Women's Hospital, Melbourne, having routine cranial ultrasound scans (< 1500 g and/or of gestational age 相似文献   

A novel system for providing compatible blood to patients during surgery: "self-service" electronic blood banking by nursing staff

BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up.     

Evaluation of factor VIII-rich cryoprecipitate and the plasma fibronectin-rich, heparin-precipitable fraction prepared from single- donor plasma units

A plasma fibronectin-rich component was prepared by heparin-induced 4 degrees C precipitation of fresh or stored (21 days at 4 degrees C), single-donor plasma. The recovery of plasma fibronectin was 45 percent at a concentration of 0.05 mg heparin per ml (7.5 units/ml) and 75 percent at 0.1 mg per ml (15 units/ml). The biologic activity of plasma fibronectin, as assessed by the spreading of Chinese hamster ovary cells or attachment of monocytes to gelatin-coated surfaces, was similar to that of plasma fibronectin concentrates made from fresh or stored plasma. Only 20 to 30 percent of the factor VIII activity in fresh plasma was recovered in cryoprecipitate produced after the heparin-induced precipitate containing fibronectin was removed. Cryoprecipitate prepared from the supernatant plasma that remains after heparin-induced cold precipitation in the presence of CaCl2 (5 mM) contained approximately 50 percent less factor VIII. The relatively low recovery of factor VIII in cryoprecipitate prepared from fibronectin-depleted plasma makes cryoprecipitation an unsuitable method of producing fibronectin-rich and factor VIII-rich components effectively from a single unit of fresh plasma. However, heparin-induced cold precipitation provides an efficient method for preparing plasma fibronectin concentrates from small plasma pools or single units of stored or fresh plasma.     

Low tuberculosis notification in mountainous Vietnam is not due to low case detection: a cross-sectional survey

Background  

Studies show that tuberculosis notification declines with increasing altitude. This can be due to declining incidence or declining case detection. In Vietnam notification rates of new smear-positive tuberculosis in the central mountainous provinces (26/100,000 population) are considerably lower than in Vietnam in general (69/100,000 population). In order to clarify whether this is explained by low incidence or low case detection, we aimed to assess the prevalence of new smear-positive tuberculosis among adults with prolonged cough in three mountainous provinces in central Vietnam.     

Kaposi's sarcoma (KS)-associated herpesvirus-like DNA sequences in peripheral blood mononuclear cells: association with KS and persistence in patients receiving anti-herpesvirus drugs

Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed.