Injection drug use among street-involved youth in a Canadian setting

Background  

Street-involved youth contend with an array of health and social challenges, including elevated rates of blood-borne infections and mortality. In addition, there has been growing concern regarding high-risk drug use among street-involved youth, in particular injection drug use. We undertook this study to examine the prevalence of injection drug use and associated risks among street-involved youth in Vancouver, Canada.     

Influence of clinical status on the association between plasma total and unbound bilirubin and death or adverse neurodevelopmental outcomes in extremely low birth weight infants

Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants.     

Impact of HIV-positive speakers in a multicomponent, school-based HIV/STD prevention program for inner-city adolescents.

Qualitative and quantitative data from Safer Choices, a school-based multicomponent HIV prevention program, were examined to determine the impact of HIV-positive speakers on inner-city adolescents' HIV risk perception and empathy for people with HIV or AIDS. Inductive analyses were used to assess student reactions to speakers. Multilevel regression modeling techniques were used to analyze student survey data (n = 1,491) to determine the effect of speakers alone, as well as in combination with the multicomponent intervention, and a knowledge-based curriculum (comparison condition). Results showed that speakers were highly popular with students and teachers, and had a positive short-term impact on students' attitudes. Although not statistically significant, the combination of intervention and speakers had the greatest impact on outcome variables. Integrating HIV-positive speakers into multicomponent programs may have a positive impact on inner-city youth. Utilizing speakers without other educational components may have minimal effects. Strategies for training and utilizing HIV-positive speakers in school settings are included.     

Immunohistochemistry of the blood group A,B,H isoantigens and Oxford Ca antigen as prognostic markers for stage IB squamous cell carcinoma of the cervix

Currently, there is lack of a histologic classification of squamous cell carcinoma of the cervix that correlates significantly with patient survival. This study investigated the survival predictive value of two immunohistochemical markers, the blood group A,B,H isoantigens and the Oxford Ca antigen, on conventional histologic sections of tumor tissues from 85 surgically treated patients with Stage IB squamous cell cervical cancer. The results indicated that the two antigens are two distinct markers, neither of which correlates with tumor grade. The expression of the A,B,H isoantigens is significantly related to patient survival after adjustment for the depth of stromal invasion of the tumor, whereas the Oxford Ca antigen has no survival predictive value.     

Granulocyte colony-stimulating factor crosses the placenta and stimulates fetal rat granulopoiesis

We studied the effect of recombinant human granulocyte colony- stimulating factor (rhG-CSF) administration to pregnant rats upon fetal and neonatal myelopoiesis. Pregnant rats were treated with rhG-CSF twice daily for 2, 4, and 6 days before parturition. rhG-CSF crossed the placenta and reached peak fetal serum concentrations 4 hours after administration. Peak fetal serum levels were 1,000-fold lower than levels detected in the dam. Hematopoietic effects of rhG-CSF were assessed by cytologic analysis of the newborn blood, spleen, bone marrow, thymus, and liver. White blood cell counts were increased twofold to fourfold in newborns. This increase was due to circulating numbers of polymorphonuclear cells (PMN). rhG-CSF induced a myeloid hyperplasia in the newborn marrow consisting of immature and mature myeloid cells in the day-2 and day-4 treated pups. Bone marrow of pups treated for 6 days contained mostly hyper-segmented PMN with little or no increase in myeloid precursors. An increase in the number of postmitotic (PMN, bands, and metamyelocytes) and mitotic (promyeloblasts, myeloblasts, and metamyeloblasts) myeloid cells in the spleen of neonates was observed. No change was detected in splenic lymphocytes or monocytes. No effect of rhG-CSF was noted in the newborn liver or thymus. These results demonstrate that maternally administered rhG-CSF crosses the placenta and specifically induces bone marrow and spleen myelopoiesis in the fetus and neonate. The significant myelopoietic effects of rhG-CSF at low concentrations in the fetus suggest an exquisite degree of developmental sensitivity to this cytokine and may provide enhanced defense mechanisms to the neonate.     

Health care reform as perceived by first year medical students

Our study objective was to evaluate the attitudes of first year medical students toward the health care system using a self administered questionnaire to all first year medical students at the medical schools in the University of California system. Of 631 students surveyed, 94% comleted the instrument. Students were asked about their attitudes toward and familiarity with concepts in health services, access to care, and managed care. Our findings indicated that most students were unfamiliar with concepts related to health services. Students were concerned about access to care; sixty-six percent of students favor a national health insurance plan. A majority of students supported allowing patients access to the current health care system regardless of the cost or utility of a medical test or procedure. Thirty-nine percent felt that rationing health care in any form (transplants, access to the intensive care unit, etc.) is contrary to the way medicine should be practiced. 72% felt that practicing physicians had a major responsibility to help reduce health care costs. When asked about specific changes intended to control health costs, students identified reform of medical malpractice system (63%) and increased spending on preventive health (60%) as the two proposals most likely to be effective. Students generally held negative attitudes toward managed care organizations; only 10% would chose to receive their care in HMOs. We conclude that first year medical students generally have little understanding of the health care system. Despite this, they hold strong opinions about access to care, managed care organizations and strategies intended to reduce health care spending. It is up to medical educators to find creative methods of introducing these content areas into an already bulging curriculum.Funds for this study were generously provided by the L.K. Whittier Foundation. Samuel A. Skootsky's salary was in part supported by Southern California Edison.     

Pressure dermatitis from an implanted pacemaker

In this eleventh report of dermatitis conforming to the outline of an underlying pacemaker, the authors suggest that most of these reactions are isomorphic responses to expansion of the subcutaneous tissues by the hard device. Allergic contact dermatitis has been documented in a few cases.     

Effects of baseline metabolic rate on pulmonary O2 uptake on-kinetics during heavy-intensity exercise in humans

We hypothesised that initiating heavy-intensity exercise from an elevated baseline metabolic rate would result in slower Phase II O2 uptake V(O2) kinetics and a greater overall 'gain' in V(O2) per unit increase in work rate. Seven healthy males performed a series of like-transitions on a cycle ergometer: (1) from light exercise to 'moderate' exercise (80% of the gas exchange threshold, GET; L-->M); (2) from light exercise to 'heavy' exercise (40% of the difference between GET and V(O2) peak; L-->H); (3) from moderate exercise to heavy exercise (M-->H). The Phase II time constant (tau) was significantly (P<0.01) greater in the M-->H condition (48+/-11 s) compared to the L-->M and L-->H conditions (26+/-6 s versus 27+/-4 s, respectively). Moreover, the end-exercise 'gain' values were significantly different between the three conditions (L-->M, 8.1+/-0.7 mL min-1 W-1; L-->H, 9.7+/-0.4 mL min-1 W-1; M-->H, 10.7+/-0.7 mL min-1 W-1; P<0.05). This 'non-linearity' in the pulmonary V(O2) response to exercise might be attributed, at least in part, to differences in the metabolic properties of the muscle fibres recruited in the abrupt transition from a lower to a higher work rate.