Adaptive capacity in ecosystems.

Understanding the adaptive capacity of ecosystems to cope with change is crucial to management. However, unclear and often confusing definitions of adaptive capacity make application of this concept difficult. In this paper, we revisit definitions of adaptive capacity and operationalize the concept. We define adaptive capacity as the latent potential of an ecosystem to alter resilience in response to change. We present testable hypotheses to evaluate complementary attributes of adaptive capacity that may help further clarify the components and relevance of the concept. Adaptive sampling, inference and modeling can reduce key uncertainties incrementally over time and increase learning about adaptive capacity. Such improvements are needed because uncertainty about global change and its effect on the capacity of ecosystems to adapt to social and ecological change is high.

Enhancing quantitative approaches for assessing community resilience.

Scholars from many different intellectual disciplines have attempted to measure, estimate, or quantify resilience. However, there is growing concern that lack of clarity on the operationalization of the concept will limit its application. In this paper, we discuss the theory, research development and quantitative approaches in ecological and community resilience. Upon noting the lack of methods that quantify the complexities of the linked human and natural aspects of community resilience, we identify several promising approaches within the ecological resilience tradition that may be useful in filling these gaps. Further, we discuss the challenges for consolidating these approaches into a more integrated perspective for managing social-ecological systems.

Long-term survival of Stanmore total hip replacements inserted with radiolucent bone cement.

Radio-opacifiers in bone cements are an accepted part of every-day practice. They have, however, been shown to be a potential cause of an increase in third body wear and to excite bone resorption in in vitro and in vivo studies. We reviewed the results of 228 consecutive Stanmore total hip replacements performed between 1981 and 1985 in 211 patients. All were inserted with radiolucent bone cement. Information regarding whether the prosthesis had been revised was available for all patients. Seventy-three patients (83 hips) were still alive and 41 patients (44 hips) were sufficiently healthy to attend clinic. Information regarding pain level was obtained from the remaining 32 patients. When revision of the implant was taken as the end-point, there was 95% ten-year survival, 91% fifteen-year survival and 75% eighteen-year survival. These long-term results of Stanmore THRs, performed in a district general hospital, with radiolucent bone cement, compare favourably with the other published series for this implant. We did not find the inability to see the bone cement a particular disadvantage when reviewing radiographs for signs of loosening. (Hip International 2002; 12: 274-80).

Vaginal creation for müllerian agenesis.

OBJECTIVE: The purpose of this study was to determine the effectiveness of passive vaginal dilation and McIndoe vaginoplasty in the creation of a neovagina for patients with müllerian agenesis. STUDY DESIGN: Fifty-one patients with Mayer-Rokitansky-Kuster-Hauser syndrome were treated for vaginal agenesis at either Johns Hopkins Hospital or Emory University. These historic prospective data were obtained by a review of medical records and a current office or telephone consultation. Initial office visits dated from November 18, 1983, through June 6, 1998. Their progress towards both anatomic and functional success was followed through August 1, 2000, which was a range of 2 to 16.8 years. One-way analysis of variance, Student t test, and logistic regression analysis were performed when appropriate. RESULTS: Four patients were lost to follow-up in various stages of the treatment. Ten patients refused vaginal dilation and proceeded to a successful modified McIndoe vaginoplasty. Of the 37 remaining patients, 91.9% anatomic and functional success was achieved from the Ingram method for vaginal dilation. Passive dilation failed in 8.1% of patients, who underwent a modified McIndoe vaginoplasty; all neovaginal creations were successful. All patients who underwent McIndoe vaginoplasty were compliant with postoperative vaginal form use. None of our patients lost vaginal space through contractions or loss of skin graft. Of those patients for whom dilation failed, only 1 patient discontinued the study because of bleeding and discomfort. In addition, only 1 patient from the 3 cases of failure had undergone a previous hymenotomy. Interestingly, 6 patients for whom dilation was successful (6/34 patients; 17.6%) had also undergone a previous hymenotomy. The mean follow-up time for all patients in this study was 111.1 +/- 7.2 months, with a range of 25 to 188 months. The mean follow-up time for those patients for whom dilation failed or who refused dilation was significantly lower at 64.5 +/- 9.5 and 65.3 +/- 18.5 months, respectively (P <.005). The mean time to successful dilation was 11.8 +/- 1.6 months with a range of 3 to 33 months. Although longer, no statistically significant difference was observed for dilation time in those patients for whom there was a failure to achieve anatomic or functional success (20.5 +/- 12.5 months; range, 8-33 months). CONCLUSION: These data reveal that passive dilation with the Ingram method is capable of creating an adequate vaginal canal in patients with vaginal agenesis, with respect to both function and anatomy even in those patients with a previous hymenotomy and resultant scar formation. Our modified McIndoe procedure has proved to be an excellent option for patients for whom conservative dilation techniques failed and who refuse to attempt any dilation. Interestingly, our data indicate that patients may now be trending toward immediate surgical correction rather than diligently using dilation techniques to create a vaginal space.

Why older community-dwelling adults do not discuss urinary incontinence with their primary care physicians.

OBJECTIVES: This study explored reasons why older adults with urinary incontinence (UI) do not initiate discussions with or seek treatment for UI from their primary care provider. DESIGN: A randomized, prospective controlled trial involving 41 primary care sites. SETTING: Primary care practice sites. PARTICIPANTS: 49 older adults age 60 and older not previously screened for UI by their primary care doctor. MEASUREMENTS: Demographic data, self-reported bladder-control information using questionnaires, and health status. RESULTS: Adults who did not discuss UI were older, had less-frequent leaking accidents and fewer nighttime voids and were less bothered by UI than those who did. The two main reasons why patients did not seek help were the perceptions that UI was not a big problem (45%) and was a normal part of aging (19%). CONCLUSIONS: Embarrassment or lack of awareness of treatment options were not significant barriers to discussing UI. Adults with a fairly high frequency of UI (average of 1.7 episodes per day) did not view UI as abnormal or a serious medical condition.

Dynamised cast management of Achilles tendon ruptures.

Non-operative treatment of closed ruptures of the Achilles tendon within 48 h of injury has been shown to produce results comparable with surgical treatment [1,2]. We report 49 patients treated using a dynamised cast, with a mean follow-up of 42 months, in which there has been only one case of re-rupture. A total of 33 patients were reviewed clinically and measurements revealed a mean calf circumference deficit of 1 cm and a mean functional range of ankle motion deficit of 3 degrees and plantar-flexion strength of 81-90%, when compared with the contra-lateral uninjured limb. Early mobilisation of the injured Achilles tendon using a dynamised cast has produced a re-rupture rate and functional recovery that compare favourably with previously published results for patients treated operatively. Non-operative management, in this way, is well tolerated by patients and is of low cost.

Endocrinopathies associated with recurrent pregnancy loss.

Repeated pregnancy wastage is defined as the loss of three consecutive pregnancies at less than 20 weeks of gestation andfetal weight less than 500 g. This article provides guidelines to evaluate endocrinopathies associated with recurrent abortions. Thyroid disorder, although usually obvious, has a high frequency in the female population and should be evaluated and treated, if revealed. Recent studies indicate that thyroid antibodies, even in the absence of abnormal thyroid function tests, may be related to pregnancy loss. Diabetes mellitus should be controlled. Luteal phase defects should be sought and, when consistently documented, treated with clomiphene citrate or progesterone supplementation. Bromocriptine may be added to the treatment of a patient with hyperprolactinemia prior to testing for luteal phase defect. An understanding of the stress and anxiety in these couples should always be considered and included in the treatment style of the physician.

Hysteroscopic metroplasty of the Class Va uterus with preservation of the cervical septum.

OBJECTIVE: To assess the safety and efficacy of hysteroscopic resection of the uterine septum in patients with a Class Va septate uterus. DESIGN: Retrospective clinical study. SETTING: University outpatient surgical center. PATIENT(S): Twenty-one patients with Class Va uterus treated between 1985-1998 in the senior author's academic practice. INTERVENTION(S): Hysteroscopic metroplasty with preservation of cervical septum. MAIN OUTCOME MEASURE(S): Intraoperative and postoperative complications; postoperative cumulative pregnancy and delivery rates. RESULT(S): No long-term complications were encountered. Fourteen of 15 women who attempted pregnancy postoperatively delivered viable neonates; the 15th is in an ongoing pregnancy. CONCLUSION(S): Surgical correction of the complete uterine septum with preservation of the cervical septum is associated with low morbidity and satisfactory postoperative obstetric outcome.

Regulation of monocyte to macrophage differentiation by antiglucocorticoids and antioxidants.

OBJECTIVE: Our purpose was to examine RU 486 and related compounds on monocyte to macrophage differentiation through scavenger receptors and cellular adhesion. STUDY DESIGN: Human monocytes were isolated, cultured, and treated with dexamethasone, levonorgestrel, RU 486, and other structurally related compounds alone or in combination. Macrophage scavenger receptor activity, inhibited by glucocorticoids and associated in the current literature with macrophage cellular adhesion, was determined in this study by counting the number of adherent cells after treatment. In addition, fluorescent-labeled acetyl-low-density lipoprotein uptake was determined as a function of scavenger receptor biologic activity. RESULTS: Dexamethasone, levonorgestrel (antiglucocorticoid only) and RU 486 (antiglucocorticoid and antioxidant) all significantly decreased adherent macrophages (4%, 52%, and 74% of control). Levonorgestrel, however, demonstrated a marked uptake of fluorescent-labeled scavenger receptor ligand. RU 486 and dexamethasone were antagonistic when combined (P < .001); levonorgestrel was less antagonistic but, however, still significant (P < .05). Reduced RU 486 (antioxidant but loses antiglucocortioid activity) decreased cellular adhesion, yet scavenger receptor function was enhanced. Both probucol (extracellular mechanism of action) and probucol analog (intracellular action) markedly up-regulated scavenger function, but once again a separation of adhesion from scavenger activity was noted. Vitamin E (antioxidant) and onapristone (antioxidant and antiglucocorticoid) had virtually little to no effect on adhesion and scavenger receptor activity. Finally, pyrrolidine dithiocarbamate, a potent oxygen-free radical quencher, was toxic to all cells examined. CONCLUSIONS: RU 486 is a known antiglucocorticoid with novel antioxidant properties first demonstrated by our laboratories. Levonorgestrel has antiglucocorticoid but no antioxidant activity. RU 486 antagonized the inhibitory effect of dexamethasone on scavenger receptor development, whereas levonorgestrel was stimulatory. A separation of scavenger receptor-induced cellular adhesion and scavenger receptor internalized ligand was demonstrated by (1) reduced RU 486, which loses its antiglucocorticoid activity but retains its antioxidant activity, and (2) probucol analog, which is chemically altered to allow intracellular entry. Glucocorticoids decrease the development of scavenger receptors, whereas antioxidants regulate inflammatory cytokines by intracellular mechanisms. It is therapeutically important to up-regulate scavenger receptor activity by antiglucocorticoids in the peritoneal cavity of women with endometriosis. However, because these mechanisms also induce inflammatory cytokines, a balance of antioxidants and antiglucocorticoids such as those demonstrated in the above study may prove beneficial.

The effect of RU 486 and related compounds on cultured macrophage differentiation and function.

OBJECTIVE: Our purpose was to examine RU 486 and related compounds on macrophage scavenger receptors and cellular adhesion. STUDY DESIGN: THP-1 cells were activated with phorbol myristate acetate and treated with dexamethasone, levonorgestrel, and RU 486 alone or in combination. Scavenger receptor activity was determined by counting adhered cells. In addition, fluorescently labeled acetyl low density lipoprotein uptake was determined. RESULTS: Both dexamethasone and RU 486 significantly decreased activated macrophages (81% and 26% of control). Levonorgestrel stimulated adherent cells in activated monocytes (130% of control). RU 486 and dexamethasone were antagonistic when combined (p < 0.001). In contrast, dexamethasone could not overcome the stimulatory effect of levonorgestrel (p < 0.001). Fluorescent studies yielded similar results. CONCLUSIONS: RU 486 is a known antiglucocorticoid with novel antioxidant properties. Levonorgestrel has antiglucocorticoid but no antioxidant activity. Glucocorticoids decrease scavenger receptors and antioxidants regulate inflammatory cytokines. RU 486 antagonized the inhibitory effect of dexamethasone on scavenger receptors, whereas levonorgestrel was stimulatory. It is therapeutically important to up-regulate scavenger receptor activity by antiglucocorticoids in the peritoneal cavity of women with endometriosis. However, because these mechanisms also induce inflammatory cytokines, a balance of antioxidants and antiglucocorticoids may prove beneficial.

Effect of RU-486 and related compounds on the proliferation of cultured macrophages.

PROBLEM: Macrophages are implicated in the pathophysiology of endometriosis and are influenced by anti-inflammatory steroids as well as anti-oxidants. METHODS: We tested the effect of RU-486, an antiprogesterone, antiglucocorticoid and an antioxidant, on the proliferation of RAW macrophages. RESULTS: The incorporation of 3H-thymidine was significantly inhibited by both progesterone and RU-486. Progesterone and RU-486, in combination, synergistically inhibited macrophage growth. In contrast, dexamethasone-stimulated growth was antagonized by RU-486 in a dose dependent manner. ZK 112,993 which is structurally related to RU-486 but lacks antioxidant properties, also inhibited thymidine incorporation. The synergistic effect of RU-486 and ZK 112,993 with progesterone implicate a mechanism of action separate from receptor bound antagonists. A cell permeable antioxidant, pyrrolidine dithiocarbamate was very effective in inhibiting the incorporation of 3H-thymidine into cells. CONCLUSIONS: These results suggest novel therapeutic modalities in the management of endometriosis via antiglucocorticoid as well as antioxidant mechanisms.