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PubMed1994

Reduction in perineural scar formation after laminectomy with Polyactive membrane sheets.

STUDY DESIGN: The effectiveness of Polyactive (Osteotech, Inc., Shrewsbury, NJ), an elastomeric segmental copolymer, as a barrier material for the prevention of perineural scar formation was evaluated in eight adult mongrel dogs. Two animals each were killed at 2, 4, 8, and 12 weeks postoperation. OBJECTIVE: This study determined the ability of a Polyactive membrane to prevent perineural scar and compared the results to those obtained using free fat graft and nonimplanted control subjects. SUMMARY OF BACKGROUND DATA: Perineural scar formation after laminectomy presents considerable morbidity in lumbar surgery. To date, a wide variety of materials has been evaluated to prevent scar formation including free fat grafts, mechanical barrier devices, hemostatic agents, and anti-inflammatory drugs. However, all studies indicate scar formation is present, and the search for an effective barrier continues. METHODS: Gross dissection, radiographic studies, including computed tomography and magnetic resonance imaging, and histologic sections were used to evaluate the presence and degree of perineural scarring. If scarring was evident in each of the evaluations, the degree was graded on a 0-3 scale where: 0 = no scarring; 1 = mild scarring; 2 = moderate scarring; and 3 = extensive scar formation. RESULTS: Polyactive membranes were an effective barrier with only minimal scar formation to the dura observed at any time period. Free fat graft was an effective barrier to scar formation at early time periods; however, progressive fat graft degradation with some increased scarring was observed at latter time periods. Nonimplanted control defect sites resulted in moderate to severe scar formation to the dura as early as 2 weeks postimplantation. CONCLUSIONS: The results indicate Polyactive is a reliable and effective means of reducing perineural scar formation. The effectiveness of the Polyactive membrane could be improved markedly if techniques or methods to ensure retention of the membrane in the proper position were developed.

Adipose Tissue↗
PubMed2005

Probing the barrier for CH2CHCO --> CH2CH + CO by the velocity map imaging method.

This work determines the dissociation barrier height for CH2CHCO --> CH2CH + CO using two-dimensional product velocity map imaging. The CH2CHCO radical is prepared under collision-free conditions from C-Cl bond fission in the photodissociation of acryloyl chloride at 235 nm. The nascent CH2CHCO radicals that do not dissociate to CH2CH + CO, about 73% of all the radicals produced, are detected using 157-nm photoionization. The Cl(2P(3/2)) and Cl(2P(1/2)) atomic fragments, momentum matched to both the stable and unstable radicals, are detected state selectively by resonance-enhanced multiphoton ionization at 235 nm. By comparing the total translational energy release distribution P(E(T)) derived from the measured recoil velocities of the Cl atoms with that derived from the momentum-matched radical cophotofragments which do not dissociate, the energy threshold at which the CH2CHCO radicals begin to dissociate is determined. Based on this energy threshold and conservation of energy, and using calculated C-Cl bond energies for the precursor to produce CH2CHC*O or C*H2CHCO, respectively, we have determined the forward dissociation barriers for the radical to dissociate to vinyl + CO. The experimentally determined barrier for CH2CHC*O --> CH2CH + CO is 21+/-2 kcal mol(-1), and the computed energy difference between the CH2CHC*O and the C*H2CHCO forms of the radical gives the corresponding barrier for C*H2CHCO --> CH2CH + CO to be 23+/-2 kcal mol(-1). This experimental determination is compared with predictions from electronic structure methods, including coupled-cluster, density-functional, and composite Gaussian-3-based methods. The comparison shows that density-functional theory predicts too low an energy for the C*H2CHCO radical, and thus too high a barrier energy, whereas both the Gaussian-3 and the coupled-cluster methods yield predictions in good agreement with experiment. The experiment also shows that acryloyl chloride can be used as a photolytic precursor at 235 nm of thermodynamically stable CH2CHC*O radicals, most with an internal energy distribution ranging from approximately 3 to approximately 21 kcal mol(-1). We discuss the results with respect to the prior work on the O(3P) + propargyl reaction and the analogous O(3P) + allyl system.

Journal Article↗
PubMed2006

A national survey of terrorism preparedness training among pediatric, family practice, and emergency medicine programs.

OBJECTIVES: Domestic terrorism is a real threat focusing on a need to engage in effective emergency preparedness planning and training. Front-line physicians are an important component of any emergency preparedness plan. Potential victims of an attack include children who have unique physiologic and psychological vulnerabilities in disasters. Front-line providers need to have adequate training to effectively participate in local planning initiatives and to recognize and treat casualties including children. The goal of the survey was to assess the current state of terrorism preparedness training, including child victims, by emergency medicine, family practice, and pediatric residency programs in the United States and to assess methods of training and barriers to establishing effective training. METHODS: A survey was e-mailed to a comprehensive list of all US pediatric, family practice, and emergency medicine residency programs 3 times between September 2003 and January 2004. The survey measured the perceived risk of terrorist attack, level of training by type of attack, level of training regarding children, method of training, and barriers to training. RESULTS: Overall, 21% of programs responded (46 of 182 pediatric, 75 of 400 family practice, and 29 of 125 emergency medicine programs). Across all of the event types, emergency medicine programs were more likely to report adequate/comprehensive training. However, < 50% of emergency medicine programs report adequate training for children. Didactic classroom-based lectures were the most commonly used method of training. Emergency medicine programs were more likely to use scenario-based exercises. Among programs that use scenario exercises, 93% report that they never (40%) or only sometimes (53%) incorporate child victims into the scenarios. Time, funding, access to subject matter experts, and availability of training material are the most important barriers to effective training. CONCLUSIONS: Children are a precious national resource and a vulnerable population in disasters. Despite the availability of terrorism preparedness funding, these data suggest that we are failing to provide adequate training to front-line providers who may care for children in a catastrophic domestic terrorist event.

Child↗
PubMed1993

Sex and the nation's health.

The Government's 'Health of the Nation', influenced by the WHO's 'Global Strategy for Health for All by the Year 2000', pledges a reduction in sexually transmitted diseases in general and AIDS in particular. The recommendations are clearly sensible but how do you persuade people to believe and comply with the 'sensible' advice? Failure to consider public health measures involving sexual behaviour without considering how different cultures respond and interpret the advice given is bound to fail. People are individuals and there is a danger in assuming that our values and beliefs are shared by people globally. For a message to succeed it needs to be simple and direct, and portrayed in its cultural context through an appropriate medium. An appreciation that the message however sensible may clash with individual needs (eg the economics of prostitution) and research into these aspects of sexual behaviour will ensure that the message remains effective. Changing the slogans and methods of conveying the message regularly will help to reinforce key points and reduce apathy.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Attitudes of males on contraception: a KAPE survey.

Acceptance of Family Planning services has been at a very slow pace in Africa. It was generally believed that the African male, due to his conservatism, was an obstacle to the acceptance of contraception by the African female. The study however showed that this was not true. The attitude of the African male towards contraception has changed drastically during the last thirty years, from ultra-conservatism during the 60s to very liberal in the 80s and 90s. Further it can be said that the African male is as well informed and has the same degree of Family Planning and child spacing acceptance-level as his counterpart in the developed world. However the African male does not accompany his partner for Family Planning Counselling. The study showed that most African men associate Family Planning with the use of condoms and not other methods such as the pill or the intrauterine devices.

Botswana↗
PubMed2000

Tolerance induction for solid organ grafts with donor-derived hematopoietic reconstitution.

Tolerance of transplanted tissue has been a focus of immunologists for decades. Indeed, to some the birth of immunology and the search for tolerance of the non-self are synonymous. One of the most powerful and reproducible methods of tolerance induction to allogeneic tissue has involved infusion of donor-specific hematopoietic cells. Under certain conditions, such infusion can result in hematopoietic reconstitution that can be experimentally accomplished at a variety of different time-points in the life of an organism from the in utero period through adulthood, reconstitution at each time-point involving consideration of a different set of immunological and physiological parameters. When high levels of donor-derived hematopoietic reconstitution are achieved, tolerance induction to donor-specific antigens is reproducible and long-lasting. Unfortunately, however, clinical efforts to achieve such high levels of hematopoietic reconstitution have historically been unsuccessful or fraught with complications. Transplantation efforts have been plagued by failure of engraftment, graft-vs-host disease (GVHD), or severe immunoincompetence of the recipient. Laboratory and clinical efforts during the last decade have resulted in a variety of developments that may overcome these barriers: (1) methods have been devised in which cells that cause GVHD can be depleted from the hematopoietic graft while hematopoietic reconstitution potential is preserved, (2) methods of harvesting large numbers of cells with multilineage reconstitution potential have been devised (an accomplishment that seems to allow the immunological barrier to be overwhelmed), and (3) capitalizing on the above two principles, minimally toxic preconditioning regimens have been designed that allow allogeneic engraftment. This review will focus on some of the experimental and clinical data of the past and the experimental and clinical issues that loom ahead.

Animals↗
PubMed2001

Reliability of adolescents' self-reported sexual behavior: a comparison of two diary methodologies.

PURPOSE: To evaluate techniques for measuring high-risk sexual behaviors by comparing the reliability and acceptability of two daily sexual behavior diary modes: a written calendar and an automated telephone interview. METHODS: This randomized controlled study included 105 sexually active female adolescents aged 15-19 years recruited from among teens seeking reproductive health care services at a family planning clinic in the San Francisco Bay Area. Participants completed a standardized sexual behavior questionnaire each day for 4 weeks. Contraceptive use by method type was recorded. Reporting differences between the two diary modes were assessed using generalized estimating equations, concordance of diary and retrospective interview responses was evaluated using kappa statistics, and contingency table analysis and Poisson regression models were constructed to examine mode acceptability. RESULTS: Respondents randomized to the telephone diary cohort reported less frequent use of barrier contraceptive methods, specifically less spermicide use (odds ratio 0.27, 95% confidence interval 0.08, 0.95), and decreasing male condom use over time, whereas reports of male condom use increased for written diary respondents (p = .007). Participant characteristics associated with diary acceptability, defined as the frequency of diary completion, were assessed and teens classified as higher risk provided fewer diary reports (p < .01). Regardless of mode completed, 65% of respondents believed the telephone diary would be preferable to the written diary for most teens. CONCLUSIONS: The automated telephone diary offered an acceptable, even preferred, methodologic alternative to the written diary calendar and elicited more accurate reporting of selected contraceptive behavior.

Adolescent↗
PubMed1999

Women's satisfaction with birth control: a population survey of physical and psychological effects of oral contraceptives, intrauterine devices, condoms, natural family planning, and sterilization among 1466 women.

User satisfaction and the physical and psychological effects of five commonly used contraceptive methods were investigated in a population survey among 1466 West German women. The focus was on effects attributed by current and past users to these methods, rather than objectively assessed effects, to shed further light on personal experiences that are highly relevant to the user but often remain unknown to prescribers and unreported in the medical literature. Within the overall sample, 1303 women were surveyed concerning their current or past use of oral contraceptives (OC), 996 regarding condoms, 342 with respect to intrauterine devices (IUD), 428 in regard to natural family planning (NFP), and 139 in relation to sterilization (respondents completed questions about each method used). It emerged that satisfaction was greatest with sterilization (92% of users), followed by OC (68% of ever users), IUD (59%), NFP (43%), and condoms (30%). Almost one in three NFP users had experienced an unwanted pregnancy during use of this method, as compared with one in 20 OC and condom users. The majority of users reported no mood changes during use of the methods studied. The percentages reporting negative mood changes (various items were scored) were up to 16% among OC users, 23% among condom users, and 30% among NFP users. The latter observations suggested that subjective side effects of a contraceptive agent on mood generally reflected, at least in part, the user's sense of confidence in the method concerned (notably, with regard to efficacy and safety). Oral contraceptives, IUD, and sterilization had a broadly positive impact on sex life, whereas that of condoms was often negative. Whereas OC users often reported less heavy and painful menstruation (in up to 56% of cases), IUD were associated with heavier, prolonged, and more painful menstruation (in up to 65% of cases), as also was sterilization, although to a lesser extent (in up to 32% of cases). Overall, the study findings indicated that OC and sterilization had less negative impact on physical and psychological functioning than the other methods studied, in contrast to what the general public often believes.

Adult↗
PubMedDate not supplied

Does the timing of the first family planning visit still matter?

CONTEXT: The timing of a first family planning visit relative to first intercourse can affect the likelihood of an early unintended pregnancy. METHODS: Nationally representative data from the 1982, 1988 and 1995 cycles of the National Survey of Family Growth were used to examine changes in the timing of first family planning visits and to explore the degree to which young women are now more likely than in the past to practice contraception independently of making a visit to a provider. Cox proportional hazards models were used to estimate how background variables, visit status and the initiation of contraceptive use affected risks of unintended pregnancy in the four years preceding each survey. RESULTS: The proportion of women who waited a month or more after their first intercourse to see a provider grew slightly between 1978 and 1995, from 76% to 79%; women waited a median of 22 months after first intercourse in 1991-1995. Any contraceptive use at first intercourse increased among both women who delayed a first visit (from 51% to 75%) and among those whose first visit occurred before their first intercourse or within the same month (from 61% to 91%). Cox proportional hazards analysis suggests that the protective effect of a first family planning visit decreased over the period studied, due in part to the increase in early contraceptive use. CONCLUSIONS: The importance of the first family planning visit appears to be declining, as sexually active young women who delay their first visit increasingly do so because they are already using a provider-independent method (primarily the condom). Thus, a multifaceted approach to providing family planning may now be needed, in which independent method use and visits to providers both play a role.

Adolescent↗
PubMed1985

Contraceptive method switching among American female adolescents, 1979.

Better knowledge about contraceptive use in adolescents is needed if pregnancy prevention is to be improved. Data from the 1979 National Survey of Young Women were used to examine method switching once contraceptive use had begun among 449 never-pregnant young women who reported premarital intercourse more than once. Bivariate chi2 tests and multivariate logit regression were used to examine factors related to switching in four analyses: overall switching; switching among those with one intercourse partner; and switching from nonmedical and medical methods separately. Frequency of intercourse and type of first method had an interactive effect on switching; length of exposure to switching, type of relationship, and reason for choosing the first method were also significant. These results suggest that providers and educators should consider the circumstances under which contraceptive methods are chosen and used by young women when counseling them as to what method may be best for them.

Adolescent↗
PubMed1991

Trends in contraception and sterilization in Australia.

Life-history data collected in a national survey of women in 1986 are used to derive the first national estimates of trends in contraception and sterilization in Australia over the last 30 years. The pill rapidly became the method of choice after its release in 1961. The intrauterine device, the other truly modern method, has never attained the same popularity. The move toward sterilization dates from the early 1970s and has been so complete that women of 35 or older are now more likely to be protected by a ligation or laparoscopic sterilization than by the pill or, indeed, by all other methods combined. Unmarried women are now indistinguishable from married women on the basis of their use of contraception, and childless married women are now more likely to be using a reversible method than married women with children.

Adolescent↗
PubMedDate not supplied

Determinants of trends in condom use in the United States, 1988-1995.

CONTEXT: Although overall condom use has increased substantially over the past decade, information is needed on whether dual method use has also become more common. In addition, there is little information on which characteristics of women influence condom use and dual method use, and on whether these characteristics have changed over time. METHODS: Data from the 1988 and 1995 National Surveys of Family Growth are examined to evaluate trends in condom use--either use alone or use with another highly effective method (dual method use). Logistic and multinomial regression analyses are presented to analyze the influence of women's characteristics on condom use. RESULTS: Current condom use rose significantly between 1988 and 1995, from 13% to 19% of all women who had had sex in the past three months. Dual method use increased from 1% in 1988 to 3% in 1995, still a very low level. In both years, current condom use was higher among women younger than 20 (32-34% in 1995) than among those aged 30 or older (less than 20% in 1995). Likewise, current condom use was most common among never-married women who were not cohabiting in both 1988 (20%) and in 1995 (34%). Multivariate analyses showed that women in the early stage of a relationship (six months or less in duration) were much more likely than those in a long-standing relationship (five years or more in length) to use the condom (odds ratio, 1.5). In both 1988 and 1995, younger women and better educated women were more likely to be currently using the condom than were older or less-educated women. For example, in 1995, women younger than 18 were 1.8 times as likely as 40-44-year-olds to be using condoms, and college graduates were 1.5 times as likely as high school graduates to do so. Further, women who were not in a union and either had never been married or were formerly married were more likely to be current condom users in 1995 than were married women (odds ratios, 1.5-1.9). Poor women were less likely than higher income women to be condom users in 1995 (odds ratios, 0.7-0.8), but poverty had made little difference in 1988. Groups likely to be dual method users were those also likely to be at greater risk of sexually transmitted disease: women in a union of less than six months duration (2.8), women younger than 20 (4.6-6.8), unmarried women (2.8-7.5) and women with two or more partners in the past three months (1.7). CONCLUSIONS: While the increase in condom use, especially among unmarried and adolescent women, is encouraging, condom use overall is substantially less than that needed to protect women and men against sexually transmitted diseases (including HIV). Moreover, steps need to be taken to understand why levels of dual method use are low and how they may be increased.

Adolescent↗
PubMed1980

[Is today's condom better than its reputation?].

In a statistical sample of 500 unwanted pregnancies surprisingly the share of women whose partners used a condom was not higher than the share of IUP-users (considering the relative frequency of use of both methods). This result was the motivation to investigate once more the use of the condom. After a short description of the history, the production, and the testing methods a discussion follows of the frequency of its use. In many countries the frequency of using the condom lies between that of hormonal oral contraceptives and the IUP. Today the reliability of the condom is higher than described in medical textbooks. In statistics of the seventies the failure rate is no more than 3 unwanted pregnancies in 100 years of usage. Harmful side effects or contraindications are not known. Therefore in cases of incompatibility or refusion of hormonal oral contraceptives reflections of the doctor on useful alternative methods of contraception should include the recommendation of the condom.

Contraceptive Devices, Male↗
PubMedDate not supplied

[Significance of bromide levels in evaluation of the hemato-encephalic barrier during acute viral meningitis].

INTRODUCTION: Inflammatory diseases of the CNS are associated with increased permeability of blood-brain barrier due to vasculitis of cerebral blood vessels leading to regional ischaemia and necrosis. Many substances pass easily from the serum into the CSF through inflamed and damaged blood-brain barrier. Bromide partition test is one of the parameters for evaluation of the blood-brain barrier integrity during CNS inflammatory diseases. As early as 1929 Walter published a monograph on blood-brain barrier accentuating the value of bromide partition test for evaluation of the functional status of blood-brain barrier. In healthy individuals bromide partition test usually ranges from 2.9-3.5. In most patients with TB meningitis bromide partition test remains below 1.6 while it is usually higher in patients with serous meningitis of other aetiologies. However, the low bromide partition test may associate also some other viral and other serous meningitides accompanied with severe lesions of the blood-brain barrier, resulting in increased passage of sodium bromide from the serum into the CSF, so that the serum/CSF ratio is lower. The aim of th study was to calculate and analyze the results of bromide partition test in patients with acute viral meningitis and hyperproteinorachia above 0.70 g/l and to calculate and analyze the results of bromide partition test in patients with TB and parasitic meningitis. The results of bromide patirion tests were compared with results of other parameters for evaluation of the blood-brain barrier function. METHOD: Titration method was used to determine the serum sodium bromide and CSF ratio. Sodium bromide oxidation into sodium bromate was the principle, where addition of potassium iodide is followed by release of equivalent amount of elementary iodide. Iodide is titrimetrically evidenced with thyosulphate, with starch as an indicator. In addition to bromide partition test functional condition of blood-brain barrier was also evaluated by albumin coefficients, albuminorachia and total proteinorachia. RESULTS: In 6 of 30 patients (20%) with acute viral meningitis the bromide partition ratio was below 1.6, suggesting severe damage of blood-brain barrier in these patients: albumin coefficients exceeded 16.7 (mean = 24.7), albuminorachia was over 0.90 (mean = 1.38 g/l), and total proteinorachia over 3.0 g (mean = 3.1 g/l). The aetiology was confirmed in all patients: lymphocyte choriomeningitis virus in 5, COX B1 in one. Values of bromide partition test were higher on follow-up examination, and values of other parameters decreased, suggesting restitution of blood-brain barrier. The results are given in Table 1. Most severe damage of blood-brain barrier was evidenced in patients with lymphocyte choriomeningitis. Parameters for evaluation of functional condition of blood-brain barrier in patients with lymphocyte choriomeningitis and TB meningitis with most severe damage of the barrier, were compared. The results are given in Table 2. No differences between the compared parameters were found, i.e. no difference in the severity of blood-brain damage. Bromide patition test values were below 1.6 in all patients with TB meningitis and in 3 of 5 patients with parasitic meningitis. DISCUSSION: Numerous studies have shown that bromide patition test value during TB meningitis was usually below 1.6. This is probably due to hypersensitivity reaction of the meninges to tuberculin which is located intrathecally and leads to blood-brain barrier damage. Use of antituberculous drugs does not affect the bromide partition test values in early stages of the disease. In all of our 15 patients with TB meningitis the bromide partition test values were below 1.6, coinciding with reference reports. However, we also measured bromide partition test values below 1.6 in 6 (20%) of 30 patients with acute viral meningitis with proteinorachia above 0,70 g/l (ABSTRACT TRUNCATED).

Acute Disease↗