A novel orthotopic model of breast cancer metastasis to bone

Breast cancer affects approximately one woman in twelve and kills more women than any other cancer. If detected early, patients have a five year survival rate of 66%, but once metastatic disease has developed, there is no effective treatment. About 70% of patients with metastatic disease have bone involvement, while lungs and liver are the other common targets. Bone metastases cause severe pain, pathological fractures and hypercalcaemia and thus are a significant clinical problem. The development of new therapies for metastatic breast carcinoma depends on a better understanding of the mechanism of homing of the tumour cells to bone, liver and lungs and the factors required for their growth in these organs. Research on mechanisms of breast cancer metastasis, particularly to bone, has relied on in vitro studies or on tumour models in which the inoculation route is designed to promote delivery of tumour cells to a specific organ. Metastases in bone are achieved by inoculation into the right ventricle of the heart. To our knowledge there has been no report of a model of metastatic spread from the mammary gland to distant sites which reliably includes bone. In this paper, we describe our recent development of a novel murine model of metastatic breast carcinoma. The new model is unique in that the pattern of metastatic spread closely resembles that observed in human breast cancer. In particular, these murine breast tumours metastasise to bone from the primary breast site and cause hypercalcaemia, characteristics not normally found in murine tumours, but common in human disease. Furthermore, in a preliminary characterisation of this model, we show that secretion of parathyroid hormone-related protein, a role for which has been implicated in breast cancer spread to bone, correlates with metastasis to bone. This model therefore provides an excellent experimental system in which to investigate the factors that control metastatic spread of breast cancer to specific sites, particularly bone. The special advantage of this system is that it involves the whole metastasis process, beginning from the primary site. Existing models consider mechanisms that pertain to growth of tumour once the site has been reached. An understanding of the regulation of these factors by potential therapeutic agents could lead to improvement in therapies designed to combat metastatic disease. For the first time, this development will allow exploration of the molecular basis of site-specific metastasis of breast cancer to bone in a clinically relevant model.

Brief behavioural skills building intervention for female controlled methods of STD-HIV prevention: outcomes of a randomized clinical field trial

The need for female controlled methods for preventing HIV infection is well recognized and women have been found to accept the female condom for these purposes. Women (n = 105) were randomly assigned to receive either (a) a 3-h behavioural skills building intervention that concentrated on educating women about the female condom, motivating female condom use, and building behavioural skills relevant to using the female condom, or (b) a time-matched broadly defined women's health education intervention. Women who received the female controlled skills building intervention used the female condom to a greater extent than did women in the health education condition. Importantly, the effects of the behavioural skills intervention were most pronounced for women who reported only one male sex partner in the previous 6 months compared to women with multiple sex partners. However, female condom use was modest, with only one in 5 vaginal intercourse acts being protected by female condoms among women with one partner who received skills training. Interventions are needed to further enhance use of the female condom and new female controlled methods are needed for the majority of women at risk who did not adopt the female condom.

Possible mechanisms of salt-induced hypertension in Dahl salt-sensitive rats

Genetic factors, diet, and salt sensitivity have all been implicated in hypertension. To further understand the mechanisms involved in salt-induced hypertension, cardiovascular, hemodynamics, and biochemical parameters in Dahl salt-sensitive rats were evaluated in animals on high- and low-sodium diets. During a 4-week treatment period, blood pressure was significantly elevated in the high (8.0%) salt group compared to the low (0.3%) salt group (p< or =0.05 for weeks 2 and 4, respectively). No significant changes were observed in heart rate. The increase in blood pressure was associated with significant increases in lower abdominal aortic and renal vascular resistance, along with a reduction in blood flow. A fourfold increase in arginine vasopressin was observed in animals on the high-salt diet. In contrast, there was no effect on plasma sodium, potassium, or aldosterone levels during the treatment period. As measured in isolated aortic rings, the high-salt diet also caused a significant elevation in stimulated norepinephrine release and a reduction in cyclic GMP levels. These data suggest that salt-induced elevation in blood pressure is due to activation of both the sympathetic and arginine vasopressin systems via mechanisms involving decreased cyclic GMP generation in vascular smooth muscle.

Can we improve the uptake of gastroscopy in the population at risk for gastric cancer? The effect of home letter information

The poor outlook for gastric cancer in Britain is largely due to late diagnosis. Earlier diagnosis will require both easy access to endoscopy and increased public awareness of dyspeptic symptoms. We used information by personal letter to encourage reporting of potentially significant symptoms in patients over 40 years of age. The aim of this study was to measure the acceptability and effect on gastroscopy rates of home letter information. Patients over 40 registered with 12 general practices were used in the study (practice population 80,000). Patients over 40 from another nine practices (practice population 46,500) acted as controls. A letter encouraging consultation for new dyspeptic symptoms was sent to all study subjects. Gastroscopy rates were compared in both study and control populations. Questionnaires on symptoms were sent to 500 study subjects. The principal outcome measure was the gastroscopy rate in people over 40 in both populations, before and during the intervention. The gastroscopy rate was 23% higher in the study than in the control population during the study (3.32 vs. 2.7%, P = 0.00016, chi 2 = 14.25). Gastroscopy uptake increased by 85% from 1991/2 to 1993/4 in the study group and by 34% in the control group (chi 2 = 14.02, P = 0.00018). Thirty-one per cent of questionnaire respondents had dyspeptic symptoms; only 3% had 'significant' symptoms of between 2 and 52 weeks duration. Home letters are an acceptable and efficient method of increasing gastroscopy uptake in dyspeptic patients over 40.

Assisted conception in HIV discordant couples: evaluation of semen processing techniques in reducing HIV viral load

Artificial insemination with motile spermatozoa prepared from HIV-infected men using standard procedures has been employed with many HIV-discordant couples. We have demonstrated that processing semen from HIV positive men can reduce HIV levels, measured as HIV1 RNA copies/ml using nucleic acid based sequence amplification (NASBA), to undetectable levels (less than 400 copies/ml) but not in all samples. We believe that all processed samples should be tested prior to insemination.

Screening and brief intervention for high-risk college student drinkers: results from a 2-year follow-up assessment

This randomized controlled trial evaluated the efficacy of a brief intervention designed to reduce the harmful consequences of heavy drinking among high-risk college students. Students screened for risk while in their senior year of high school (188 women and 160 men) were randomly assigned to receive an individualized motivational brief intervention in their freshman year of college or to a no-treatment control condition. A normative group selected from the entire screening pool provided a natural history comparison. Follow-up assessments over a 2-year period showed significant reductions in both drinking rates and harmful consequences, favoring students receiving the intervention. Although high-risk students continued to experience more alcohol problems than the natural history comparison group over the 2-year period, most showed a decline in problems over time, suggesting a developmental maturational effect.

AIDS treatment advances and behavioral prevention setbacks: preliminary assessment of reduced perceived threat of HIV-AIDS

Recent advances in AIDS treatment have brought renewed optimism for prolonging the lives of those infected with HIV. This article examined beliefs about how new treatments may reduce HIV transmission risk among 298 HIV-negative gay and bisexual men attending a gay pride festival. Results from an anonymous survey showed that men who practiced unprotected anal intercourse as the receptive partner (UAR intercourse) were younger, less well educated, and more likely to believe that it is safe to have UAR intercourse with an HIV-positive man who has an undetectable viral load and that new treatments for HIV relieve their worries about unsafe sex. As HIV treatments continue to advance, new challenges for HIV prevention will likely emerge.

Is HIV/STD control in Jamaica making a difference?

OBJECTIVE

To assess the impact of the comprehensive HIV/STD Control Program established in Jamaica since the late 1980s on the HIV/AIDS epidemic.

METHODS

AIDS case reports, HIV testing of blood donors, antenatal clinic attenders (ANC), food service workers, sexually transmitted disease (STD) clinic attenders, female prostitutes, homosexuals and other groups were used to monitor the HIV/AIDS epidemic. Primary and secondary syphilis and cases of congenital syphilis were also monitored. National knowledge, attitude and practice (KAP) surveys were conducted in 1988, 1989, 1992, 1994 and 1996.

RESULTS

The annual AIDS incidence rate in Jamaica increased only marginally in the past three years from 18.5 per 100000 population to 21.4 in 1997. HIV prevalence in the general population groups tested has been about 1% or less. Among those at high risk, HIV prevalence rates have risen to 6.3% (95% confidence interval 5.0-8.0) in STD clinic attenders, around 10% and 21% in female prostitutes in Kingston and Montego Bay respectively and approximately 30% among homosexuals. Syphilis rates and congenital syphilis cases have declined. The proportion of men aged 15-49 years reporting sex with a non-regular partner declined from 35% in 1994 to 26% in 1996 (P< 0.001). Women ever having used condoms increased from 51% in 1988 to 62.5% in 1992 and 73% in 1994 and 1996 (P< 0.001), while condom use with a non-regular partner increased from 37% in 1992 to 73% in 1996 (P= 0.006). Condom use among men was high over the period: around 81% had ever used condoms and 77% used them with non-regular partners. Gay men, inner-city adults and adolescents aged 12-14 years all reported increases in condom use while condom sales and distribution increased from around 2 million in 1985 to 10 million in 1995.

CONCLUSION

HIV/STD control measures appear to have slowed the HIV/AIDS epidemic in Jamaica, however a significant minority of persons continue to have unprotected sex in high risk situations.

Smoking and pursuit of thinness in schoolgirls in London and Ottawa

It has been proposed that teenage girls often smoke cigarettes to protect themselves from the impulse to binge eat, with its feared weight-gain consequences, particularly when other measures such as greater dietary restraint have failed. The present study looked at the relationship between body mass index and standardised questionnaire responses concerning smoking, alcohol consumption, moods, weight changes, attitudes to body weight and shape, dietary patterns and menstruation in 1936 British (London) and 832 Canadian (Ottawa) schoolgirls. Data analysis revealed links between cigarette smoking and body weight/shape concerns, and awareness by subjects of these links; there was also a tendency for smokers in these two populations to be overweight but not grossly obese. Smoking was also related at all ages to being postmenarchal. The London population in particular revealed an association between smoking and a weight loss of 7 kg or more at some stage since puberty. Smoking was also linked, in a minority, with regular vomiting undertaken as a further defence against weight gain when overeating had occurred. These associations existed alongside the major and predictable association found between alcohol consumption and smoking. Similarities between the British and Canadian schoolgirls were striking in respect of rank order of reasons given for smoking and consequences of giving it up. Since smoking amongst older women is reportedly associated with below-average body weight it may indeed be effective in helping to curb weight gain. Our study provided little evidence of association between smoking and generalised anxiety or social anxiety (in either population), or depression (in the British cohort). We suggest that any preventive psychological approach to teenage female smoking should include attention to weight gain anxiety and consequent pursuit of thinness.

Screening and brief intervention for high-risk college student drinkers: results from a 2-year follow-up assessment

This randomized controlled trial evaluated the efficacy of a brief intervention designed to reduce the harmful consequences of heavy drinking among high-risk college students. Students screened for risk while in their senior year of high school (188 women and 160 men) were randomly assigned to receive an individualized motivational brief intervention in their freshman year of college or to a no-treatment control condition. A normative group selected from the entire screening pool provided a natural history comparison. Follow-up assessments over a 2-year period showed significant reductions in both drinking rates and harmful consequences, favoring students receiving the intervention. Although high-risk students continued to experience more alcohol problems than the natural history comparison group over the 2-year period, most showed a decline in problems over time, suggesting a developmental maturational effect.

Development of a pediatric liver transplantation program in Argentina

This article describes the preliminary experimental steps and clinical implementation of a purely pediatric liver transplantation (LT) program in a large public children's hospital in Buenos Aires, Argentina, a city with well over 10 million inhabitants and a referral population of over 30 million. Between 1993 and 1997, 84 LTs were performed in 81 patients, of which one-fourth weighed below 10 kg. The main indications were biliary atresia (n = 25, 30%) and fulminant liver failure (n = 23, 27%), followed by autoimmune cirrhosis (n = 14, 16%) and other liver diseases. Shortage of organs due to local conditions led to the use of liver-reduction techniques in 48 cases (57%), split liver in 2, and living-related donor (LRD) in 2. Retransplantation was necessary in 3 instances. Seventy-eight percent of the recipients survived for more than 1 year and 71% were alive after 4 years. The authors comment on the need for adaptation to local conditioning factors when developing a pediatric LT program in any country in which demographics and economic, medical, and sociological environments have a decisive influence on organ procurement, the actual performance of the operation, and the lifelong postoperative medication. In Buenos Aires, where the hospital setting is well-developed, the indications are in part determined by the high incidence of hepatitis A. Organ shortages in our area led to liberal use of liver reduction, split-liver, and LRD techniques. The overall results of the first years of such a program were largely satisfactory.

A multicenter, randomized, blind comparison of amrinone with milrinone after elective cardiac surgery

Amrinone and milrinone are phosphodiesterase inhibitors with positive inotropic effects useful for the treatment of ventricular dysfunction after cardiac surgery. Forty-four patients undergoing elective cardiac surgery at four centers received either amrinone (n = 22) or milrinone (n = 22) in a randomized, blind fashion. Immediately after separation from cardiopulmonary bypass (CPB), two bolus doses of either amrinone 0.75 mg/kg or milrinone 25 microg/kg were administered over 30 s, separated by 5 min. Hemodynamic measurements were recorded before each dose and at the end of the 10-min study. Both amrinone and milrinone increased the cardiac index (48% vs 52%, P = not significant [NS] for amrinone and milrinone, respectively). There was a small increase in mean arterial pressure (MAP) after amrinone administration (from 68 +/- 3 to 72 +/- 3 mm Hg at 10 min, P < 0.05) with no significant change in MAP after milrinone administration. Central venous pressure was significantly higher in the amrinone group at baseline and 5 min (12 vs 10 mm Hg and 11 vs 10 mm Hg, respectively; P < 0.05). Systemic and pulmonary vascular resistances decreased significantly and to a similar extent after either amrinone or milrinone administration. Phenylephrine was required in 11 of 22 patients receiving amrinone and in 11 of 22 patients receiving milrinone to maintain arterial blood pressure. The proportion of patients requiring an intravascular volume infusion (15 of 22 vs 17 of 22, P = NS) and the total fluid volume infused were similar (402 +/- 57 vs 350 +/- 49 mL, P = NS for amrinone and milrinone, respectively). Amrinone and milrinone seem to have similar hemodynamic effects after CPB, with the exception of blood pressure, although the need for vasopressor support of blood pressure did not differ. Selection between these two drugs may include nonhemodynamic considerations such as cost.

IMPLICATIONS

Amrinone and milrinone are drugs that improve cardiac contraction. Their effects have never been directly compared in patients. We found that amrinone and milrinone produced similar hemodynamic effects in adult patients undergoing cardiac surgery. Choice between the two drugs can be based on nonhemodynamic considerations such as cost.

The four community dimensions of primary care practice

BACKGROUND

Despite the growing belief that "the community" should play a larger role in the work of physicians, there is no clear understanding of exactly how physicians should participate in their communities. The primary goals of this study were to propose and test an organizing framework that identified four distinct categories of activities whereby physicians can interact with their communities: (1) identifying and intervening in the community's health problems; (2) responding to the particular health issues of local cultural groups when caring for patients; (3) coordinating local community health resources in the care of patients; and (4) assimilating into the community and its organizations. Other goals were to characterize physicians' level of involvement in each of these four types of community activities, and to identify the correlates of greater and lesser involvement.

METHODS

A questionnaire was mailed to a random sample of 500 young primary care physicians in the United States. The response rate was 66.6%. Physicians reported how confident they were in performing each of 15 specific community-relevant activities. Confidence ratings were factor-analyzed to test the hypothesis that physician involvement in community activities can be organized into the four proposed categories. Physicians also self-rated their involvement in various community activities within each of these four categories, and predictors of involvement were identified through ordinary least-squares regression models.

RESULTS

Using factor analysis, the community activities sorted cleanly into the four postulated community dimensions of medical practice, providing a measure of validation for the distinctiveness of the four dimensions. Physicians reported active involvement in some activities (eg, speaking to community groups and gaining acceptance in their communities) and little involvement in other activities (eg, working with community groups to address local health problems, familiarity with local women's shelters). Contrary to expectations, physicians who worked with minority and poorer patient populations and counties generally reported less community involvement. Physicians caring for more patients covered by HMO or capitated health insurance plans also reported lower participation in their communities.

CONCLUSIONS

This study provides support for the hypothesis that the community plays a role in the work of physicians that can be categorized into four types of activities. This framework may help physicians and practices recognize the breadth of ways they can meet the growing demand that they approach their work with a community perspective.

Retrospective analysis of Silastic implant arthroplasty of the first metatarsophalangeal joint

The purpose of this study was to evaluate the outcome of implant arthroplasty according to subjective, biomechanic, and radiographic parameters over a long period of time. Implants in 40 feet (27 patients) were analyzed at an average follow-up time of 8.25 years and a mean patient age of 63. The results were consistent with the subjective findings of previous studies that demonstrated that most patients were satisfied with the procedure. Ninety-six percent of the patients in this study confirmed they would undergo the procedure a second time. The radiographic results did not demonstrate a high incidence of implant fracture as previously reported. This review suggests that implants can be effective when used with patients who are carefully selected according to age, activity level, and diagnosis.

Angiomyofibroblastoma--a rare but distinct entity

A case of angiomyofibroblastoma of the vulva in a 23-year-old woman is presented. Clinical, histological and immunohistochemical features as well as the differential diagnosis and prognosis of this rare but distinct entity are discussed. Only about 65 cases are documented in the literature and to our knowledge this is the first case to be reported from the Caribbean.

Cryomyolysis, a new procedure for the conservative treatment of uterine fibroids

Conservative surgical options for uterine myomata traditionally were abdominal myomectomy, laparoscopic myomectomy, and, more recently, myolysis. Each of these procedures has distinct advantages, but also apparent disadvantages. We attempted to introduce an additional option for conservative surgical treatment of fibroids by freezing the structures, a procedure termed cryomyolysis. In this pilot study, 14 women were pretreated with a gonadotropin-releasing hormone (GnRH) agonist for a minimum of 2 months preoperatively to minimize uterine and myoma size. Cryomyolysis was performed and the GnRH agonist was discontinued. Magnetic resonance imaging scans were performed in 10 of the 14 women after GnRH agonist treatment but before surgery, and 4 months postoperatively. Total uterine volume ranged from 41.3 to 1134.8 ml preoperatively, and 49.5 to 1320 ml postoperatively (mean increase 22% after discontinuation of GnRH agonist). Normal uterine volume ranged from 35.6 to 548.7 ml preoperatively and 45.1 to 729.6 ml postoperatively (mean increase 40%); however, myoma volume showed a mean decrease of 6% (range -87-28%). Analysis of only frozen myomata revealed a mean volume decrease of 10%. Cryomyolysis maintains at or slightly reduces these lesions to post-GnRH agonist size, and all other uterine tissue returns to pretreatment size. We believe cryomyolysis may be an effective conservative surgical approach to uterine fibroids.

Streptomyces thermocarboxydovorans sp. nov. and Streptomyces thermocarboxydus sp. nov., two moderately thermophilic carboxydotrophic species from soil

Four moderately thermophilic, carboxydotrophic streptomycetes were the subject of a comparative taxonomic investigation designed to establish their taxonomic relationships. Almost complete sequences of the 16S rRNA genes of the test strains were determined following the isolation and direct sequencing of the amplified genes. The resultant nucleotide sequences were aligned with the sequences of previously studied streptomycetes, and phylogenetic trees generated by using the neighbour-joining, Fitch-Margoliash, maximum-likelihood and maximum-parsimony methods. It was evident from the phylogenetic analyses that strains AT50, AT51 and AT52 were most closely related to Streptomyces thermodiastaticus DSM 40573T and strain AT37 to Streptomyces glaucescens DSM 40716 and Streptomyces pseudogriseolus NRRL 3985. Random DNA amplification profiles clearly distinguished strains AT50, AT51 and AT52 from Streptomyces thermodiastaticus and from strain AT37. The molecular systematic evidence, together with phenotypic data derived from this and previous studies, indicate that the test strains merit species status within the genus Streptomyces. The name Streptomyces thermocarboxydovorans sp. nov. is proposed for strains AT50, AT51 and AT52 (type strain) and Streptomyces thermocarboxydus sp. nov. for strain AT37.

Physician job satisfaction: developing a model using qualitative data. SGIM Career Satisfaction Study Group

The purpose of this study was to develop a current and comprehensive model of physician job satisfaction. Information was gathered by (1) analysis of open-ended responses from a large group practice physician survey in 1988, and (2) analysis of focus group data of diverse physician subgroups from 1995. Participants were 302 physicians from large-group practices and 26 participants in six focus groups of HMO, women, minority, and inner-city physicians. Data were used to develop a comprehensive model of physician job satisfaction. The large group practice survey data supported the key importance of day-to-day practice environment and relationships with patients and physician peers. Future concerns focused on the effect of managed care on the physician-patient relationship and the ability of physicians to provide quality care. Focus groups provided contemporary data on physician job satisfaction, reinforcing the centrality of relationships as well as special issues for diverse physician subgroups of practicing physicians. New variables that relate to physician job satisfaction have emerged from economic and organizational changes in medicine and from increasing heterogeneity of physicians with respect to gender, ethnicity, and type of practice. A more comprehensive model of physician job satisfaction may enable individual physicians and health care organizations to better understand and improve physician work life.

The family with AIDS: multiple challenges for caregivers

Acquired Immune Deficiency Syndrome (AIDS) continues to increase in the United States, especially among minority groups. The disease is impacting not only individuals, but entire families through multiple infections of family members. This results in simultaneous illness and multiple loss within the family system. Delivery and management of quality care for the family is often made difficult by the lack of resources experienced by families with limited income and the multiplicity of problems associated with poverty in the US. This presents numerous challenges to health care providers. Utilizing a case study, this article presents a model demonstrating the coordination of services among several providers as a means of meeting a variety of family needs and providing quality, cost-effective care.