Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Women with a sonographic short cervix in the mid-trimester are at increased risk for preterm delivery. This study was undertaken to determine the efficacy and safety of using micronized vaginal progesterone gel to reduce the risk of preterm birth and associated neonatal complications in women with a sonographic short cervix.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled trial that enrolled asymptomatic women with a singleton pregnancy and a sonographic short cervix (10-20 mm) at 19 + 0 to 23 + 6 weeks of gestation. Women were allocated randomly to receive vaginal progesterone gel or placebo daily starting from 20 to 23 + 6 weeks until 36 + 6 weeks, rupture of membranes or delivery, whichever occurred first. Randomization sequence was stratified by center and history of a previous preterm birth. The primary endpoint was preterm birth before 33 weeks of gestation. Analysis was by intention to treat.

RESULTS

Of 465 women randomized, seven were lost to follow-up and 458 (vaginal progesterone gel, n=235; placebo, n=223) were included in the analysis. Women allocated to receive vaginal progesterone had a lower rate of preterm birth before 33 weeks than did those allocated to placebo (8.9% (n=21) vs 16.1% (n=36); relative risk (RR), 0.55; 95% CI, 0.33-0.92; P=0.02). The effect remained significant after adjustment for covariables (adjusted RR, 0.52; 95% CI, 0.31-0.91; P=0.02). Vaginal progesterone was also associated with a significant reduction in the rate of preterm birth before 28 weeks (5.1% vs 10.3%; RR, 0.50; 95% CI, 0.25-0.97; P=0.04) and 35 weeks (14.5% vs 23.3%; RR, 0.62; 95% CI, 0.42-0.92; P=0.02), respiratory distress syndrome (3.0% vs 7.6%; RR, 0.39; 95% CI, 0.17-0.92; P=0.03), any neonatal morbidity or mortality event (7.7% vs 13.5%; RR, 0.57; 95% CI, 0.33-0.99; P=0.04) and birth weight < 1500 g (6.4% (15/234) vs 13.6% (30/220); RR, 0.47; 95% CI, 0.26-0.85; P=0.01). There were no differences in the incidence of treatment-related adverse events between the groups.

CONCLUSIONS

The administration of vaginal progesterone gel to women with a sonographic short cervix in the mid-trimester is associated with a 45% reduction in the rate of preterm birth before 33 weeks of gestation and with improved neonatal outcome.

Productivity is a poor predictor of plant species richness

For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters(-2)) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity and richness.

An adaptation of the Framingham coronary heart disease risk function to European Mediterranean areas

AIM

To determine whether the Framingham function accurately predicts the 10 year risk of coronary disease and to adapt this predictive method to the characteristics of a Spanish population.

METHOD AND RESULTS

A Framingham function for predicting 10 year coronary deaths and non-fatal myocardial infarction was applied to the population of the province of Gerona, Spain, where the cumulated incidence rate of myocardial infarction has been determined since 1988 by a specific registry. The prevalence of cardiovascular risk factors in this region of Spain was established in 1995 by a cross sectional study on a representative sample of 1748 people. The number of cases estimated by the Framingham function for 10 year coronary deaths and non-fatal myocardial infarction was compared with that observed. The Framingham function estimated 2425 coronary heart disease cases in women and 1181 were observed. In men, 9919 were estimated and 3706 were observed. Recalibrating the Framingham equations to the event rate and the prevalence of the risk factors in Gerona led to estimates very close to the number of cases observed in Gerona men and women.

CONCLUSIONS

The Framingham function estimates more than doubled the actual risk of coronary disease observed in north east Spain. After calibration, the Framingham function became an effective method of estimating the risk in this region with low coronary heart disease incidence.

Effect of restricting dietary protein on the progression of renal failure in patients with insulin-dependent diabetes mellitus

BACKGROUND

Restriction of dietary protein may slow the progression of renal failure in diverse renal diseases, but the extent to which such a diet is beneficial in patients with diabetic nephropathy is uncertain.

METHODS

We studied the effect of reduced intake of protein and phosphorus on the progression of renal disease in 35 patients with insulin-dependent (Type I) diabetes mellitus and clinically evident nephropathy. The low-protein, low-phosphorus diet contained 0.6 g of protein per kilogram of ideal body weight per day, 500 to 1000 mg of phosphorus, and 2000 mg of sodium. The control diet consisted of the patient's prestudy diet with the stipulation that it contain 2000 mg of sodium and at least 1 g of protein per kilogram per day and 1000 mg of phosphorus. Renal function was assessed by measurement of iothalamate and creatinine clearances at intervals of 3 to 6 months, and the patients were followed for a minimum of 12 months (mean, 34.7). The declines in mean glomerular filtration rates were compared between groups by linear-regression analysis of the glomerular filtration rate as a function of time.

RESULTS

The patients who followed the study diet for a mean of 37.1 months had declines in iothalamate clearance of 0.0043 ml per second per month and in creatinine clearance of 0.0055 ml per second per month. The comparable values in the control group were 0.0168 and 0.0135, respectively (P less than 0.05). Blood pressure was well controlled, and the degree of glycemic control was comparable in both groups.

CONCLUSION

Dietary restriction of protein and phosphorus can retard the progression of renal failure in patients with Type I diabetes mellitus who have nephropathy. We believe that wider use of this treatment is indicated.

Ubiquitous transgenic expression of the IL-23 subunit p19 induces multiorgan inflammation, runting, infertility, and premature death

p19, a molecule structurally related to IL-6, G-CSF, and the p35 subunit of IL-12, is a subunit of the recently discovered cytokine IL-23. Here we show that expression of p19 in multiple tissues of transgenic mice induced a striking phenotype characterized by runting, systemic inflammation, infertility, and death before 3 mo of age. Founder animals had infiltrates of lymphocytes and macrophages in skin, lung, liver, pancreas, and the digestive tract and were anemic. The serum concentrations of the proinflammatory cytokines TNF-alpha and IL-1 were elevated, and the number of circulating neutrophils was increased. In addition, ubiquitous expression of p19 resulted in constitutive expression of acute phase proteins in the liver. Surprisingly, liver-specific expression of p19 failed to reproduce any of these abnormalities, suggesting specific requirements for production of biologically active p19. Bone marrow transfer experiments showed that expression of p19 by hemopoietic cells alone recapitulated the phenotype induced by its widespread expression, pointing to hemopoietic cells as the source of biologically active p19. These findings indicate that p19 shares biological properties with IL-6, IL-12, and G-CSF and that cell-specific expression is required for its biological activity.

Single vs weekly courses of antenatal corticosteroids for women at risk of preterm delivery: A randomized controlled trial

CONTEXT

The practice of administering weekly courses of antenatal corticosteroids to pregnant women at risk of preterm delivery is widespread, but no randomized trial has established the efficacy or safety of this practice.

OBJECTIVES

To evaluate the efficacy of weekly administration of antenatal corticosteroids compared with a single course in reducing the incidence of neonatal morbidity and to evaluate potential complications of weekly treatment.

DESIGN AND SETTING

Randomized, double-blind, placebo-controlled intention-to-treat trial conducted in 13 academic centers in the United States from February 1996 through April 2000.

PARTICIPANTS

A total of 502 pregnant women between 24 and 32 completed weeks' gestation who were at high risk of preterm delivery.

INTERVENTION

All patients received a complete single course of antenatal corticosteroids (either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses, or dexamethasone, 6 mg intramuscularly repeated every 12 hours for 4 doses). Participants who had not delivered 1 week after receipt of the single course were randomly assigned to receive either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses every week until 34 weeks' gestation or delivery, whichever came first (n = 256), or a similarly administered placebo (n = 246).

MAIN OUTCOME MEASURE

Composite neonatal morbidity (including severe respiratory distress syndrome, bronchopulmonary dysplasia, severe intraventricular hemorrhage, periventricular leukomalacia, proven sepsis, necrotizing enterocolitis, or perinatal death).

RESULTS

Composite morbidity occurred in 22.5% of the weekly-course group vs 28.0% of the single-course group (unadjusted relative risk, 0.80; 95% confidence interval, 0.59-1.10). Neither group assignment nor the number of treatment courses was associated with a reduction in composite morbidity.

CONCLUSIONS

Weekly courses of antenatal corticosteroids did not reduce composite neonatal morbidity compared with a single course of treatment. Weekly courses of antenatal corticosteroids should not be routinely prescribed for women at risk of preterm delivery.

Bovine tuberculosis in free-ranging white-tailed deer from Michigan

A 4.5 yr-old male white-tailed deer (Odocoileus virginianus) killed by a hunter during the 1994 firearm hunting season in northeastern Michigan (USA) had lesions suggestive of tuberculosis and was positive on culture for Mycobacterium bovis the causative agent for bovine tuberculosis. Subsequently, a survey of 354 hunter-harvested white-tailed deer for tuberculosis was conducted in this area from 15 November 1995 through 5 January 1996. Heads and/or lungs from deer were examined grossly and microscopically for lesions suggestive of bovine tuberculosis. Gross lesions suggestive of tuberculosis were seen in 15 deer. Tissues from 16 deer had acid-fast bacilli on histological examination and in 12 cases mycobacterial isolates from lymph nodes and/or lungs were identified as M. bovis. In addition, lymph nodes from 12 deer (11 females and 1 male) without gross or microscopic lesions were pooled into 1 sample from which M. bovis was cultured. Although more male (9) than female (3) deer had bovine tuberculosis infections, this difference was not statistically significant. Mycobacterium bovis culture positive deer ranged in age from 1.5 to 5.5 yr with a mean of 2.7 yr (median 2.5 yr) for males and 3.2 yr (median 3.5 yr) for females. This appears to be the first epidemic occurrence of M. bovis in free-ranging cervids in North America. A combination of environmental (high deer density and poor quality habit) and management-related factors (extensive supplemental feeding) may be responsible for this epizootic.

Effects of long-term physical training on body fat, metabolism, and blood pressure in obesity

Twenty-seven women with varying degrees of obesity were physically trained for 6 mo on an ad lib. diet. Body fat changes were positively correlated with the number of fat cells in adipose tissue. Obese women with fewer fat cells decreased in weight during training whereas women with severe obesity and an increased number of fat cells even gained weight. Blood pressure decreased consistently after training. Blood pressure elevation was not associated with body fat mass, nor was a decrease in blood pressure associated with a decrease in body fat or with pretraining blood pressure level. There were, instead, correlations between decreases in blood pressure on the one hand and initial concentrations and decreases in plasma insulin and triglycerides and blood glucose on the other. These results suggest an association between elevated blood pressure and metabolic variables. The possibility of treating and preventing early essential hypertension with methods that also correct the metabolic derangement, such as diet and exercise, should be given high priority in further research.

Trillion virion delay: time from testing positive for HIV to presentation for primary care

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals' initial presentation to medical care frequently occurs at a point of advanced immunosuppression.

OBJECTIVES

To investigate the time between HIV testing and presentation to primary care. Also to examine factors associated with delayed presentation.

METHODS

One hundred eighty-nine consecutive outpatients without prior primary care for HIV infection were assessed at 2 urban hospitals: Boston City Hospital, Boston, Mass, and Rhode Island Hospital, Providence. Sociodemographics, alcohol and drug use, social support, sexual beliefs and practices, and HIV testing issues were examined in bivariate and multivariate analyses for association with delay in presentation to primary care after positive test results for HIV.

RESULTS

Of 189 patients, 74 (39%) delayed seeking primary care for more than 1 year, 61 (32%) delayed for more than 2 years, and 35 (18%) for more than 5 years after an initial positive HIV serologic evaluation. The median CD4+ cell count of subjects was 0.28 x 10(9)/L (range, 0.001-1.71 x 10(9)/L). In multiple linear regression analysis the following characteristics were found to be associated with delayed presentation to primary care after HIV testing: history of injection drug use (P<.001); not having a living mother (P=.01); not having a spouse or partner (P=.08); not being aware of HIV risk before testing (P<.001); and being notified of HIV status by mail or telephone (P=.002). An interaction effect between sex and screening for alcohol abuse was significant (P=.03) and suggested longer delays for men with positive screening test results (CAGE [an alcoholism screening questionnaire containing 4 structured questions], 2+) compared with men without positive screening test results or women.

CONCLUSIONS

Patients with positive HIV test results often delay for more than a year before establishing primary medical care. Information readily available at the time of HIV testing concerning substance abuse, social support, and awareness of personal HIV risk status is useful in identifying patients who are at high risk of not linking with primary care. Patients who were notified of their HIV status by mail or telephone delayed considerably longer than those notified in person. Efforts to ensure primary care linkage at the time of notification of positive HIV serostatus are necessary to maximize benefits for both individual and public health and should be an explicit task of posttest counseling.

Pharmacology and toxicology of a liposomal formulation of amphotericin B (AmBisome) in rodents

AmBisome is a lyophilized preparation of liposomal amphotericin B. The acute intravenous toxicity of AmBisome was evaluated in mice and rats, and the LD50S were found to be greater than 175 and 50 mg/kg, respectively. The corresponding LD50S for conventional amphotericin B were approximately 2.3 and 1.6 mg/kg for mice and rats, respectively. The multiple dose toxicity test confirmed that AmBisome was well tolerated by both species. There were no deaths observed among mice receiving 25 or 50 mg/kg AmBisome for 14 days, and only two deaths among mice receiving 75 mg/kg AmBisome. One rat died in the group receiving 25 mg/kg AmBisome for 30 days. However, five of ten and nine of ten rats died in the groups treated with 50 and 75 mg/kg AmBisome, respectively. Hepatotoxicity was evident by elevation in serum liver enzyme levels for these groups. Initial pharmacokinetic evaluations demonstrated that peak plasma concentrations of 87 and 118 mg/kg, respectively, were attained in mice and rats after injection with 5 mg/kg AmBisome. Terminal plasma half-lives of 3.36 and 7.56 h were calculated for mice and rats, respectively. Tissue accumulations of amphotericin B resulting from multiple dose intravenous administration of either conventional amphotericin B or AmBisome were determined. At equivalent doses of 1 mg/kg, AmBisome treatment resulted in higher liver and spleen uptake of drug, but lower kidney and lung uptake than amphotericin B. At 5 mg/kg, AmBisome treatment resulted in concentrations of drug in the kidney and lungs that were comparable to corresponding tissue levels observed in the group treated with 1 mg/kg conventional amphotericin B.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of alkali burns : an 11-year retrospective review

OBJECTIVE

To review the spectrum of patients with alkali burns admitted over an 11-year period and to assess the clinical outcomes after the introduction of a standard alkali burn treatment protocol.

DESIGN

Retrospective nonrandomized comparative study.

PATIENTS AND INTERVENTIONS

A total of 121 patient records with alkali burns (n = 177 eyes) admitted to a tertiary hospital between 1987 and 1998 were reviewed. Eyes treated with a standard alkali burn treatment protocol, which included intensive topical steroids, ascorbate, citrate, and antibiotics, were compared with eyes treated by conservative management with antibiotics, and a short course of steroids.

MAIN OUTCOME MEASURES

Time to corneal reepithelialization, final best-corrected visual acuity, and time to visual recovery, length of hospital stay, and complications were analyzed.

RESULTS

The standard protocol tended to delay corneal reepithelialization by one day (P: = not significant) in eyes with grade 1 burns (n = 76) and by 2 days (P: = 0.04) in grade 2 burns (n = 52), with no difference in final visual outcome. There were 37 eyes with grade 3 burns. Those treated with the standard protocol showed a trend toward more rapid corneal reepithelialization. Twenty-seven of 29 (93%) eyes with grade 3 injuries achieved a final best-corrected visual acuity of 20/40 or better compared with 3 of 6 (50%) eyes not treated according to the standard protocol (P: = 0.02). Eyes with grade 4 burns (n = 12), whether treated with the standard protocol or not, required 10 to 12 weeks for corneal reepithelialization. There was no statistically significant difference in final visual acuity.

CONCLUSIONS

On the basis of our findings, a number of recommendations can be made for the management of alkali injuries. Patients with a grade 1 or 2 injury do not require routine admission and do not benefit from the use of intensive treatment with ascorbate and citrate. A trend toward more rapid healing and a better final visual outcome were apparent in grade 3 burns, but our standard protocol made no difference in grade 4 burns.

Long-term adjustment of early-stage ovarian cancer survivors

The objectives of this study were to describe the quality of life (QOL), consequences of treatment, complementary therapy use, and factors correlating with psychologic state in 58 survivors of early-stage ovarian cancer since little is known about the QOL of early-stage ovarian cancer survivors. Survivors were interviewed using standardized measures to assess physical, psychologic, social, and sexual functioning; impact of cancer on socioeconomic status; and complementary therapy use. Survivors reported good physical QOL scores and few unmet needs. However, menopausal symptoms and negative impact on sexuality were reported. Less than 10% of survivors reported either an interest in sex or were sexually active. Psychologic assessment yielded a subset of 26% of patients with scores suggestive of posttraumatic stress disorder (PTSD) and 40% of survivors scored below the norm on the Mental Health Inventory-17 Survey. One third of patients required treatment for family/personal problems and took antianxiety medications. About 56% of survivors reported fear of cancer recurrence and 59% reported anxiety when their CA125 is tested. Better mental health was significantly related to less fatigue (Functional Assessment of Cancer Therapy [FACT]-fatigue, r = 0.61, P < 0.0001), less pain (European Organisation for Research and Treatment of Cancer [EORTC], r =-0.54, P < 0.0001), fewer stressful life events (Life Event Scale, r =-0.44, P > 0.001), and greater social support (MOS Social Support Survey, r = 0.41, P < 0.01). Early-stage ovarian cancer survivors had few physical complaints and unmet needs, but psychologic distress was evident in a subset of survivors; the majority of survivors reported sexual dysfunction. These results indicate the need for intervention and improved distress screening in the early-stage ovarian cancer population.

Small cell carcinoma of the bladder: long term outcome with integrated chemoradiation

BACKGROUND

Small cell carcinoma of the bladder (SCCB) is an uncommon tumor with approximately 8% 5-year survival reported in the literature for patients with disease confined to the pelvis. It exhibits biologic behavior similar to that of small cell carcinoma of the lung (SCLC). The authors sought to determine whether etoposide and cisplatin chemotherapy integrated with local irradiation is associated with improved survival in SCCB, as has been shown in SCLC.

METHODS

The authors performed a retrospective analysis of stage, treatment, disease free survival (DFS), and overall survival (OS) among 14 British Columbia Cancer Agency (BCCA) patients treated between 1985 and 1996 for SCCB.

RESULTS

When multiagent chemotherapy was combined with local irradiation, the authors observed a 70% 2-year and 44% 5-year actuarial OS among 10 patients without contraindications to systemic chemotherapy. Actuarial DFS was 70% at 2 and 5 years. The mean survival was 47 months (95% confidence interval, 18.5-76.1 months) and the median survival was 41 months. Nine of these patients had disease confined to the pelvis, and one had metastases to retroperitoneal lymph nodes. Five patients were alive and disease free an average of 82 months following diagnosis. Two patients had died of other causes without evidence of disease at 34 and 48 months following diagnosis. The incidence of second primary transitional cell bladder neoplasms following successful treatment was 60% at 2 years (3 of 5 long term survivors).

CONCLUSIONS

Integrated chemoradiation for patients with limited stage SCCB generates a realistic expectation of long term survival. Prospective trials to confirm these findings are warranted.

Interleukin-5 modulates eosinophil accumulation in allergic guinea pig lung

Based on its involvement in eosinophil biology, interleukin 5 (IL-5) may play a role in the pulmonary eosinophilia associated with allergic reactions. We have examined that hypothesis using a neutralizing antibody to IL-5 in ovalbumin-sensitized guinea pigs challenged with aerosolized antigen. The extent of eosinophilia has been quantitated in bronchoalveolar lavage (BAL) and by histologic evaluation of lung tissue sections. Acute intraperitoneal administration of a rat IgG, monoclonal antibody to murine IL-5 derived from TRFK-5 cells prevented lung and BAL eosinophilia in a dose-dependent fashion at and above 10 micrograms per guinea pig. Treatment with either an experimentally irrelevant, isotype-matched antibody from GL113 cells or with heat-denatured IL-5 antibody was without effect. These studies demonstrate the importance of IL-5 to pulmonary eosinophilia in challenged, allergic guinea pigs.

Substitution treatment of injecting opioid users for prevention of HIV infection

BACKGROUND

Injecting drug users are vulnerable to infection with HIV and other blood borne viruses as a result of collective use of injecting equipment as well as sexual behaviour.

OBJECTIVES

To assess the effect of oral substitution treatment for opioid dependent injecting drug users on rates of HIV infections, and high risk behaviours.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and PsycINFO to March 2007. We also searched reference lists of articles, reviews and conference abstracts

SELECTION CRITERIA

Studies were required to consider the incidence of risk behaviours, or the incidence of HIV infection related to substitution treatment of opioid dependence. All types of original studies were considered. Two reviewers independently assessed studies for inclusion.

DATA COLLECTION AND ANALYSIS

One reviewer extracted data from included studies, assessed quality and confirmed decisions by consulting with all other reviewers.

MAIN RESULTS

Thirty-three studies, involving 10,400 participants, were included. The majority were not randomised controlled studies and there were problems of confounding and bias. The studies varied in several aspects limiting the extent of quantitative analysis. Studies consistently show that oral substitution treatment for opioid-dependent injecting drug users is associated with statistically significant reductions in illicit opioid use, injecting use and sharing of injecting equipment. It is also associated with reductions in the proportion of injecting drug users reporting multiple sex partners or exchanges of sex for drugs or money, but has little effect on condom use. It appears that the reductions in risk behaviours related to drug use do translate into reductions in cases of HIV infection.

AUTHORS' CONCLUSIONS

Oral substitution treatment for injecting opioid users reduces drug-related behaviours with a high risk of HIV transmission, but has less effect on sex-related risk behaviours. The lack of data from randomised controlled studies limits the strength of the evidence presented in this review.

Effect of a prior-authorization requirement on the use of nonsteroidal antiinflammatory drugs by Medicaid patients

BACKGROUND

Prior authorization--mandatory advance approval for the use of expensive medications--is now the primary method by which Medicaid programs control expenditures for drugs. However, whether this policy reduces expenditures for specific drugs without causing the unwanted substitution of other drugs or medical services has been largely unstudied. We evaluated the effects of a prior-authorization policy involving nongeneric nonsteroidal antiinflammatory drugs (NSAIDs) in the Medicaid program in Tennessee.

METHODS

We compared monthly Medicaid expenditures that were potentially affected by the policy change during the year before and the two years after its implementation. We studied prescriptions for NSAIDs, other analgesic or antiinflammatory drugs, and psychotropic drugs, as well as outpatient services and inpatient admissions for the management of pain or inflammation.

RESULTS

At the midpoint of the base-line year, 495,821 people were enrolled in Medicaid. During that year, mean annualized Medicaid expenditures for NSAID prescriptions amounted to $22.41. Expenditures decreased by 53 percent (95 percent confidence interval, 48 to 57 percent) during the next two years, for an estimated savings of $12.8 million. The reduction in expenditures resulted from the increased use of generic NSAIDs, as well as from a 19 percent decrease in overall NSAID use (95 percent confidence interval, 13 to 25 percent). There was no concomitant increase in Medicaid expenditures for other medical care. Regular users of nongeneric NSAIDs, those most affected by the policy change, had similar reductions in NSAID expenditures and use, with no increase in expenditures for other medical care.

CONCLUSIONS

Prior-authorization requirements may be highly cost effective with regard to expenditures for NSAIDs, drugs that have very similar efficacy and safety but substantial variation in cost.

Plant species' origin predicts dominance and response to nutrient enrichment and herbivores in global grasslands

Exotic species dominate many communities; however the functional significance of species' biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant species at 64 grasslands in 13 countries, and at a subset of the sites we experimentally tested native and exotic species responses to two fundamental drivers of invasion, mineral nutrient supplies and vertebrate herbivory. Exotic species are six times more likely to dominate communities than native species. Furthermore, while experimental nutrient addition increases the cover and richness of exotic species, nutrients decrease native diversity and cover. Native and exotic species also differ in their response to vertebrate consumer exclusion. These results suggest that species origin has functional significance, and that eutrophication will lead to increased exotic dominance in grasslands.

It remains unclear whether exotic and native species are functionally different. Using a global grassland experiment, Seabloom et al. show that native and exotic species respond differently to two globally pervasive environmental changes, addition of mineral nutrients and alteration of herbivore density.

Clean intermittent catheterization in spinal cord injury patients: long-term followup of a hydrophilic low friction technique

Clean intermittent self-catheterization is an established option in bladder management of spinal cord injury patients. Several early and a small number of long-term studies have reported good preventive or therapeutic effects on hydronephrosis, vesicourethral reflux, urinary tract infection and incontinence. Most reports describe the use of small catheters and liberal use of jelly but urethral complications, such as strictures and false passages, seem to increase with the length of followup. All 30 spinal cord injury patients in this retrospective study had used disposable hydrophilic, low friction catheters from the early shock phase to a median of 7 years (range 5 to 9). There were 26 upper motor neuron and 4 lower motor neuron lesions. After tap water soaking, the surface layer of the catheter coating has a friction constant more than 10 times lower than that for a regular plastic catheter (Nélaton) with chlorhexidine jelly. There was no hydronephrosis, pyelonephritis or renal scarring. In 3 patients who had decreased the clean intermittent self-catheterization regimen, signs of upper tract dilatation developed but the excretory urogram returned to normal after correction of the regimen. Of 30 patients 12 (40%) maintained sterile urine, while 4 of the remaining 18 with bacteriuria had episodes of urinary sepsis and chronic infections. Two patients had epididymitis. Of 6 men with occasional insertion difficulties when the clean intermittent self-catheterization regimen started after the indwelling catheter had been removed 4 showed yielding signs of strictures during the subsequent clean intermittent self-catheterization regimen. In 1 patient 2 dilation attempts had failed but the patient can perform the clean intermittent self-catheterization regimen. One patient with Crohn's disease had advanced urethral changes in the acute phase but could perform clean intermittent self-catheterization with a small catheter. One patient has had recurrent modifications of the urethral wall but no development of a false passage. The study indicates that patients who use hydrophilic low friction low friction catheters do as well as or better than patients using conventional catheters. Above all, there is no increase in severe urethral complications with time after injury. Progression towards strictures after early urethral trauma seems to be preventable by the use of this catheter.

Regional sympathetic function in high spinal cord injury during mental stress and autonomic dysreflexia

Centrally mediated sympathetic stimulation of subjects who have suffered a spinal cord injury (SCI) does not activate the decentralized part of the body below the level of the lesion, whereas experimental data indicate an exaggerated response above the level of the lesion. SCI subjects may exhibit an autonomic dysreflexia reaction following afferent stimulation below the level of the lesion. In order to investigate the function of the sympathetic nervous system above and below the level of the lesion, regional noradrenaline spillover was measured by means of steady-state isotope dilution technique above (forearm) and below (leg) the level of the lesion at baseline, during mental stress and following bladder stimulation in nine SCI subjects (mean age 41 years; level of injury C7-T4; mean duration of injury 13.8 years). The results from the SCI subjects were also compared with those from 10 weight- and age-matched control subjects, both at rest and during mental stress. Body composition was determined by dual energy X-ray absorptiometry scanning and arm/leg blood flow by occlusion plethysmography. At baseline, total and regional noradrenaline spillover did not differ between the groups. Mental stress increased mean arterial pressure in both groups. Heart rate (76 versus 64 beats/min; P < 0.05) and arm noradrenaline spillover (2.73 versus 1.71 pmol/min/100 g; P < 0.05) increased more in spinal cord injury subjects than in control subjects, whereas total body (2826 versus 3783 pmol/min; P < 0.01) and leg noradrenaline spillover (0.23 versus 0.41 pmol/min/100 g; P < 0.05) increased only in the control group. During bladder stimulation, SCI subjects reacted with a marked increase in mean arterial pressure and leg noradrenaline spillover (from 0.06 to 0.91 pmol/min/100 g; P < 0.05) and their leg blood flow decreased. Regional and total noradrenaline clearance were similar in the two groups. In conclusion, peripheral afferent stimulation below the level of the lesion in spinal cord injury subjects gives rise to a marked noradrenaline spillover from the decentralized part of the sympathetic nervous system suggesting a remaining, but qualitatively altered, neuronal function. Centrally mediated stimulation induced an exaggerated response above the level of the lesion.

Integrating the underlying structure of stochasticity into community ecology

Stochasticity is a core component of ecology, as it underlies key processes that structure and create variability in nature. Despite its fundamental importance in ecological systems, the concept is often treated as synonymous with unpredictability in community ecology, and studies tend to focus on single forms of stochasticity rather than taking a more holistic view. This has led to multiple narratives for how stochasticity mediates community dynamics. Here, we present a framework that describes how different forms of stochasticity (notably demographic and environmental stochasticity) combine to provide underlying and predictable structure in diverse communities. This framework builds on the deep ecological understanding of stochastic processes acting at individual and population levels and in modules of a few interacting species. We support our framework with a mathematical model that we use to synthesize key literature, demonstrating that stochasticity is more than simple uncertainty. Rather, stochasticity has profound and predictable effects on community dynamics that are critical for understanding how diversity is maintained. We propose next steps that ecologists might use to explore the role of stochasticity for structuring communities in theoretical and empirical systems, and thereby enhance our understanding of community dynamics.

Physical and sexual abuse in women infected with the human immunodeficiency virus: increased illness and health care utilization

BACKGROUND

A history of physical or sexual abuse is associated with increased health care utilization and possibly an increase in illness based largely on self-reported data.

OBJECTIVE

To examine whether victimization experience is associated with increases in documented medical disease and health care utilization among women infected with the human immunodeficiency virus (HIV).

METHODS

We interviewed and reviewed medical record data of 50 women seeking initial primary care for HIV infection at 2 urban hospitals. Women with and without a history of physical and sexual abuse were compared. Using multiple regression analysis, 2 periods were examined: entire life before study entry and the subsequent 2 years. The characteristics examined included episodic disease, chronic disease, sexually transmitted disease, chronic pain syndrome, opportunistic infections, obstetrical history, and number of injuries, surgical procedures, hospitalizations, ambulatory care visits, and emergency department visits.

RESULTS

Evidence of physical or sexual abuse was found in 34 (68%) of the 50 women, of whom 16 (32%) did not disclose during the interview that they were abused. At entry, the rates of episodic disease, chronic pain syndrome, and sexually transmitted disease were greater among those women with histories of abuse. At 2 years, episodic disease, chronic disease, injuries, emergency department visits, and hospitalizations were all more likely in abused women.

CONCLUSION

Physical and sexual abuse are common and associated with increased medical disease and health care utilization among HIV-infected women.