An investigation into the cytotoxic effects of microbubbles and their constituents on osteosarcoma and bone marrow stromal cells.

BACKGROUND: Ultrasound-responsive microbubbles offer a means of achieving minimally invasive, localised drug delivery in applications including regenerative medicine. To facilitate their use, however, it is important to determine any cytotoxic effects they or their constituents may have. The aim of this study was to test the hypothesis that phospholipid-shelled microbubbles are non-toxic to human bone-derived cells at biologically-relevant concentrations. METHODS: Microbubbles were fabricated using combinations of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), 1,2-dibehenoyl-sn-glycero-3-phosphocholine (DBPC), polyoxyethylene(40) stearate (PEG40S) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene-glycol)-2000] (DSPE-PEG2000). Microbubble size and concentration were measured as a function of time and temperature by optical microscopy. Effects on MG63 osteosarcoma and human bone marrow stromal cells (BMSCs) were measured for up to 72 h by assay for viability, metabolic activity and proliferation. RESULTS: DBPC:DSPE-PEG2000 microbubbles were significantly more stable than DSPC:PEG40S microbubbles under all conditions tested. Serum-containing medium had no detrimental effect on microbubble stability, but storage at 37 °C compared to at 4 °C reduced stability for both preparations, with almost complete dissolution of microbubbles at times ≥24 h. DSPC:PEG40S microbubbles had greater inhibitory effects on cell metabolism and growth than DBPC:DSPE-PEG2000 microbubbles, with PEG40S found to be the principle inhibitory component. These effects were only evident at high microbubble concentrations (≥20% (v/v)) or with prolonged culture (≥24 h). Increasing cell-microbubble contact by inversion culture in a custom-built device had no inhibitory effect on metabolism. CONCLUSIONS: These data indicate that, over a broad range of concentrations and incubation times, DBPC:DSPE-PEG2000 and DSPC:PEG40S microbubbles have little effect on osteoblastic cell viability and growth, and that PEG40S is the principle inhibitory component in the formulations investigated.

Risperidone versus clozapine in treatment-resistant chronic schizophrenia: a randomized double-blind study. The Risperidone Study Group.

OBJECTIVE: The purpose of this study was to compare the short-term efficacy and safety of risperidone and clozapine in treatment-resistant chronic schizophrenic patients. METHOD: In a controlled double-blind, multicenter study, 86 inpatients with chronic schizophrenia (DSM-III-R), who were resistant to or intolerant of conventional neuroleptics, were randomly assigned to receive risperidone or clozapine for 8 weeks after a 7-day washout period. After a 1-week dose-titration phase, doses were fixed at 6 mg/day of risperidone and 300 mg/day of clozapine for 1 week and then adjusted according to each patient's response. The final mean doses were 6.4 mg/day of risperidone and 291.2 mg/day of clozapine. Treatment efficacy and safety were evaluated with several well-known rating scales. RESULTS: Both risperidone and clozapine significantly reduced the severity of psychotic symptoms (scores on the Positive and Negative Syndrome Scale and the Clinical Global Impression scale) from baseline, with no significant between-group differences. At endpoint, 67% of the risperidone group and 65% of the clozapine group were clinically improved (reduction of 20% or more in total Positive and Negative Syndrome Scale score). Risperidone appeared to have a faster onset of action. In both groups extrapyramidal symptoms and other adverse events were few, and their severity was generally mild. Neither group showed evidence of a relation between drug plasma concentrations and clinical effectiveness. CONCLUSIONS: Risperidone was well tolerated and as effective as medium doses of clozapine in patients with chronic schizophrenia who had been resistant to or intolerant of conventional neuroleptics.

Mutagenesis of Streptococcus equi and Streptococcus suis by transposon Tn917.

Genetic tools for studying streptococci are much less sophisticated than those that are available for many other bacterial genera. In this paper, we describe the development of a transposon mutagenesis system that we have used to mutate two important veterinary streptococci, Streptococcus equi and Streptococcus suis. The system uses a temperature-sensitive suicide vector to deliver Tn917 via electroporation, transposing Tn917 into the chromosomal DNA of the two streptococci. The transposon insertions can be rescued from the streptococcal chromosomes by plasmid rescue and selection in E. coli, with subsequent insertion site analysis by DNA sequencing. Transposition appeared to have occurred in an essentially random fashion when chromosomal DNA of S. suis and S. equi mutants was analysed by Southern blotting. However, when analysis of 60 S. equi mutants was carried out using the S. equi genome sequence database, 60% of transposon insertions had occurred within a 15 kb region of the genome whereas the other insertions appeared to have occurred essentially randomly. This finding suggests that Southern blot analysis for assessing the randomness of transposon libraries may need to be interpreted with caution. However, this observation notwithstanding, the Tn917 based system described in this paper will facilitate the study of S. suis and S. equi.

Prior nonfatal firearm injuries in detainees of a large urban jail.

Detainees of large urban jails have may health risks including injuries related to violence and firearms. A survey of 582 randomly selected detainees entering the Cook County Department of Corrections during the summer of 1994 found that 51 percent had previously entered hospitals for violence-related injuries, and 26 percent survived prior gunshot wounds. Patterns of firearm injuries were different from patterns of violence affecting the general population. Factors common to those with prior firearm injuries included witnessing a shooting at an early age, tattoos, previous sexually transmitted diseases, easy access to a semiautomatic weapon, and prior incarceration. Implications and prevention strategies are discussed.

[The level of glycohaemoglobin (Hb A1c) in connection with diabetes and pregnancy (author's transl)]. / Dosage de l'hémoglobine glycosylée (Hb A1c) dans l'association "diabète et grossesse".

The authors worked out a normal curve using 379 levels obtained over 9 months in 180 normal pregnancies. 6% (with a confidence level between 4.4% and 7.6%) was usual for haemoglobin A1c. Then they compared 42 levels of glycohaemoglobin obtained from 14 pregnant diabetic patients where the mean value was 8.34%. Glycohaemoglobin A1c therefore is a good indicator or the level of stabilisation in diabetic pregnancies in the two months before the estimation is taken. It is therefore possible to think that it does indicate chronic hyperglycaemia and does seem to have a future in screening diabetic pregnancies. On the other hand it does not seem to be of any supplementary value in monitoring the fetus of the diabetic mother in the third trimester of pregnancy because of the small variations in the levels that are obtained as compared with the suddenness of fetal complications.

[The value of estimating the levels of amniotic insulin which come from the fetus in looking after diabetic pregnancies in the last trimester (author's transl)]. / Intérêt du dosage de l'insuline amniotique d'origine foetale dans la surveillance des grossesses de diabétique au dernier trimestre.

The authors carried out 49 estimations of amniotic fluid levels of insulin in 41 patients. 25 of these patients were non-diabetic and they were a control group, and 16 patients were diabetic (24 estimations). The liquor was collected by amniocentesis between the 32nd and the 42nd week of amenorrhoea. The mean of the control levels was 3.17 micro-units per ml. The mean of the values in diabetic pregnancies was 9.97 micro-units per ml. The difference between the two groups is statistically significant. We have studied this insulinaemia in relationship to the duration of the diabetes, the maternal weight increase, the levels of insulin used therapeutically, the blood glucose level, the rise in arterial blood pressure, the weight of the infant, the date of delivery, the presence of fetal distress and the control of blood sugar. There is a statistically significant difference between the insulinaemia of patients in whom the diabetes is well controlled (mean level of 7.08 micro-units per ml) and the patients in whom the diabetes is badly controlled (31.7 micro-units per ml). This new parameter for supervision of the third trimester of pregnancy in diabetics gives rise to the possibilities of a better approach to materno-fetal blood sugar regulation and to an adjustment of the therapeutic doses of insulin that are given which will result in lengthening of the duration of pregnancy, with the aim of achieving a spontaneous vaginal delivery at term.

When criminals are shot: A survey of Washington, DC, jail detainees.

INTRODUCTION: Criminals are at high risk of being victims of violence, but little is known about their victimization. METHODS: A screen of Washington, DC, detainees found that 1 in 4 had been wounded in events that appear unrelated to their incarceration. Extensive interviews were conducted with 79 men entering the city jail from March through June 1997; the men reported 93 prior events in which they had been shot within the past 5 years. RESULTS: Eighty-three percent had personally witnessed someone being shot, and 46% had a family member killed with a gun. In the incidents in which they were shot, most were victims of robberies, assaults, and crossfires. The shootings were serious -- 35% were hit by more than 1 bullet, more than 90% went to the hospital, and 40% still had some disability from the wounds. These detainees report being shot by other criminals rather than by law-abiding citizens. Ninety percent would prefer to live in a world without easy access to firearms. CONCLUSION: These young men live in a violent world of gunplay. The overwhelming majority would prefer that firearms were not so readily available.

In a randomized, double-blinded, placebo-controlled trial, the single oral dose typhoid vaccine, M01ZH09, is safe and immunogenic at doses up to 1.7 x 10(10) colony-forming units.

M01ZH09, S. Typhi (Ty2 Delta aroC Delta ssaV) ZH9, is a single oral dose typhoid vaccine with independently attenuating deletions. A phase II randomized, double-blind, placebo-controlled, dose-escalating trial evaluated the safety and immunogenicity of M01ZH09 to 1.7 x 10(10) colony-forming units (CFU). 187 Healthy adults received vaccine or placebo in four cohorts. Serologic responses and IgA ELISPOT were measured. At all doses, the vaccine was well tolerated and without bacteremias. One subject had a transient low-grade fever. 62.2-86.1% of subjects seroconverted S. Typhi-specific LPS IgG and 83.3-97.4% IgA; 92.1% had a positive S. Typhi LPS ELISPOT. M01ZH09 is safe and immunogenic up to 1.7 x 10(10)CFU. Efficacy testing of this single-dose oral typhoid vaccine is needed.

A role for the primary care physician in counseling young African-American men about homicide prevention.

Homicide is the leading cause of death in African-American men aged 15-34 years, yet physicians rarely discuss homicide prevention with patients. The authors propose that physicians have a role in preventing homicide similar to their role in other preventive medicine issues. This study evaluated patients' responsiveness to a physician's counseling about firearms and homicide. While being treated for unrelated problems at a walk-in ambulatory clinic, 53 African-American men patients received brief counseling by the physician about six preventive medicine topics, including firearms. A postvisit interview demonstrated that the discussion of firearms was well received and recalled more than any other preventive medicine issue discussed.

Do criminals go to the hospital when they are shot?

OBJECTIVES: To determine whether criminals go to the hospital when they are shot. Such information is needed to check on the accuracy of using hospital emergency room data to estimate non-fatal gunshot wounds. SETTING: Five jails across the US. METHODS: A survey of inmates being booked into jail, administered by in-house health care staff. RESULTS: Over 90% of over 300 criminals who had been wounded sometime before their incarceration reported going to a hospital for treatment after being shot. These results are consistent with previous findings from one jail. CONCLUSIONS: Jail inmates who had previously been shot were likely to have been treated in a hospital. This limited finding is consistent with the proposition that hospital/emergency department data may miss only a small percentage of gunshot wounds to criminals.

Medical care solicitation by criminals with gunshot wound injuries: a survey of Washington, DC, jail detainees.

BACKGROUND: The best estimates of nonfatal gunshot wounds in the United States come from hospital emergency room data and may miss, among other things, wounded individuals who do not seek medical treatment. Criminals may be those least likely to rely on professional care for their wounds. This study provides evidence of whether medical care is solicited by criminals after gunshot wounds. In addition, the circumstances of the injury events are described. METHODS: A case series of 79 detainees at a Washington, DC, jail who had previously been shot in 93 separate incidents were interviewed using a standardized questionnaire. Data were obtained concerning the age and race of the victim, the location of the wound, and the length of hospital stay. RESULTS: In 92% of the incidents, respondents reported going to the hospital; one-third of those shot were hospitalized for more than 1 week. More than half (54%) had been hit in the head or torso, and 40% had a current disability attributable to the wound. CONCLUSION: Among these "criminals," the vast majority reported that they obtained professional care for their gunshot wounds. Such evidence suggests that individuals previously thought unlikely to enter the medical care system after a firearm injury usually do so. Statistics on medically treated nonfatal gunshot wounds probably do not substantially underestimate the actual number of nonfatal shootings.