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PubMed2004

Treatment of hypogonadism in men with chronic kidney disease.

Hypogonadism is common among men with chronic kidney disease, but few studies have directly assessed the effects of testosterone replacement in this population. Limited information suggests that androgen replacement may improve libido and sexual function among men who are frankly hypogonadal. However, the threshold for normal sexual function is in the lower end of the normal range. Increasing serum testosterone above this level does not appear to have beneficial effects on sexual functioning. On the other hand, at least among healthy men, the dose-response curve for anabolic effects of testosterone administration appears to extend to testosterone levels on the high end of the normal range or above. Small studies have suggested that androgen treatment has anabolic effects among end-stage renal disease patients, even in the absence of hypogonadism. Androgens have potential side effects, and some preinitiation and subsequent assessment and monitoring are recommended to minimize these adverse effects. Recommendations for healthy older men appear to be reasonable for patients with chronic kidney disease. More research is needed to measure the effects of androgen therapy on various symptoms of hypogonadism as well as on overall quality of life, physical functioning, and survival among patients with chronic kidney disease.

Androgens↗
PubMed1992

Patterns of demographic change in the Americas.

Considerable scholarly debate has focused on the nature of demographic change in the Americas before and after 1492. Recent research on human skeletal samples and related archeological materials suggests that morbidity and mortality were increasing throughout much of the Western Hemisphere before 1492 in response to increased population density, increased sedentism, and changing subsistence. The evidence suggests that after 1492 population reduction was caused not by continental pandemics but by localized or regional epidemics augmented by social and economic disruption. The twentieth century has witnessed remarkable Native American population recovery, fueled both by improvements in health care and changing definitions of "being Indian."

Disease Outbreaks↗
PubMed1990

[Surgery of endomyocardial fibrosis. Apropos of 32 cases].

From 1971 to 1984, 32 patients with endomyocardial fibrosis (EMF) were treated by endocardial resection (decortication) and valve replacement. The population consisted in 20 men and 12 women (age ranged from 8 to 64); 19 patients were european and 13 african. All were symptomatic, 78 p. 100 in stages III or IV of the NYHA. Hypereosinophilia was detected in 21 patients and its cause was determined in 11 cases. Cardiac involvement was biventricular in 22 patients and monoventricular in 10 patients. Six patients died in the immediate postoperative period and 6 late deaths were observed, owing to extracardiac causes in 4. There were no recurrence of EMF. Despite a high mortality rate, the authors suggest that all symptomatic EMF should benefit from endocardial resection.

Adolescent↗
PubMed1989

Balance in family planning.

Family planning has been so effective in Singapore that a risk exists of there being too few young people to sustain the country's economy in the twenty-first century. Relaxation of birth control policies and immigration laws offers hope that this problem will be averted.

Family Planning Services↗
PubMed1987

Hydroxyurea treatment of myeloproliferative disorders. Macro-megaloblastic blood and bone marrow changes.

Blood and bone marrow changes induced by continuous low-dose hydroxyurea treatment are described. A linear increase in mean red cell volume was observed after onset of therapy. The entire normocyte population was replaced by abnormally large erythrocytes within 150 days. The bone marrow morphology changed in megaloblastic direction. Bone marrow iron stores and number of sideroblasts increased, findings compatible with ineffective erythropoiesis. Serum folate and cobalamin levels remained normal. These morphologic changes might cause confusion when examining blood or bone marrow samples from patients treated with hydroxyurea.

Bone Marrow↗
PubMed1994

[Fluctuation of HCV quasi-species population during interferon therapy; analysis by single strand conformation polymorphism].

We investigated the fluctuation of hepatitis C virus (HCV) quasispecies during interferon therapy by single strand conformation polymorphism (SSCP) analysis. In 13 of 16 interferon ineffective patients, the predominant HCV population was replaced with other quasispecies during the treatment. Especially, in 9 patients, a part of the HCV quasispecies, pre-existing before interferon therapy, became predominant after the therapy. These results indicate that sensitivity to interferon differs among HCV quasispecies and that interferon selects resistant HCV strains. Existence of such HCV quasispecies seems to be associated with interferon treatment failure.

Base Sequence↗
PubMed1998

[Long-term survival rate of tibial osteotomies for valgus gonarthrosis].

PURPOSE OF THE STUDY: High tibial osteotomy (HTO) is a routine procedure for medial gonarthrosis. Mid-term results are known to be satisfactory, but they deteriorate with longer follow-up. The authors present a long term survival analysis of 109 out of 111 consecutive HTO with a minimal potential follow-up of ten years. MATERIAL AND METHODS: 111 patients were consecutively operated on for isolated primary varus gonarthrosis between 1977 and 1985: 57 men and 54 women, with a mean age of 53 years (range, 27 to 79 years). X-ray measurements were done on stance, hip-ankle view. Global axial deformation was defined as the angle between mechanical axes of femur and tibia. The respective part of congenital and degenerative tibial deformation was assessed according to Dejour. The angle between femoral and tibial bicondylar lines, representing lateral instability, was added to the tibial degenerative deformation to represent the total degenerative deformation. The goal of correction was a 3 to 7 degree mechanical valgus angulation. At the time of bone healing, 82 patients (74 per cent) had an optimal correction. Two patients were excluded from the follow-up study because of a severe complication (1 bacterial arthritis and 1 tibia non union) which could interfere with the long term result. The 109 remaining patients were followed for a minimal period of 1 year (mean: 8.4 years). GUEPAR pain grading and the occurrence of a revision were prospectively analyzed. 57 non reoperated patients could be re-examined at a mean maximal follow-up of 13.5 years (range, 10 to 18 years). Failure was defined as either the occurrence of a grade 2 or 3. GUEPAR pain during the whole follow-up, or a clinical or functional Knee Society score < 80 points at final follow-up, or revision. Failure and revision rates were calculated according to Kaplan and Meier. RESULTS: 11 patients were reoperated on before final examination (10 per cent): 2 medial unicondylar and 9 total knee prostheses. At final follow-up, the mean clinical and functional scores were respectively 87.0 points (range, 24 to 100 points) and 86.3 (range, 45 to 100 points). The cumulative failure rate was 33 per cent after 10 years and 54 per cent after 15 years; the respective revision rates were 9 per cent and 19 per cent. A pre-operative total degenerative deformation superior to 3 degrees led to a 3.5 fold increased failure rate (p < 0.000,1). A pre-operative medial joint space narrowing over the half of the normal, lateral one led to a 2.2 fold increased failure rate (p = 0.014). An optimal post-operative correction led to a 3.2 fold decreased failure rate (p = 0.000,1). For a given total degenerative deformation, patients with a congenital deformation superior to 5 degrees had a significant lower failure rate (p < 0.000,1). No factor significantly influenced the revision rate. DISCUSSION: Ideal patients for HTO, with an expected survival rate of 100 per cent after 13 years, have moderate degenerative changes and a congenital deformation superior to 5 degrees. Patients with advanced degenerative changes and no congenital deformation experienced a 35 per cent failure rate after 10 years. In this population, unicondylar replacement should be considered as a valuable alternative.

Adult↗
PubMed1998

[Treatment of knee osteoarthritis].

Osteoarthritis of the knee is not a well defined illness, but is a result of different causes that may lead to joint failure due to chondral damage, synovial inflammation, subchondral bone formation, and the formation of osteophytes along the joint lines. The pathogenesis is unclear. We still lack treatment to cure the early process of chondral degeneration. The treatment of choice in early and moderate osteoarthritis of the knee is limited to counselling, physiotherapy, analgesics, and surgical correction of malalignment. Documentation is still lacking on chondral debridement and transplantation of the degenerated cartilage by cultured chondrocytes, periosteum or perichondrium. An effective and well documented treatment of end-stage osteoarthritis of the knee in the older population is replacement of the joint by a knee prosthesis.

Analgesics↗
PubMed2001

In vivo modulation of the splenocyte yield and composition by female sex steroid hormones.

The study was designed to shed more light on the controversial role of the two main ovarian steroid hormones (i.e. estradiol and progesterone) in shaping the size and phenotypic characteristics of the splenic lymphocyte pool. For this purpose ovariectomized adult rats (OVX) were treated for 14 subsequent days with either estradiol or progesterone (to attain physiological concentrations of the hormones). Afterwards, the splenocyte yield, and overall number of splenocytes bearing TCR alpha beta receptor, CD4 and CD8 coreceptor were evaluated. Fourteen-day-long ovarian hormone deprivation produced an increase in the splenic weight and splenocyte yield (on the account of a rise in the number of TCR alpha beta- cells), although the number of TCR alpha beta+ cells was reduced as a result of a decrease in the size of the CD4+ cell subpopulation. Replacement of either estradiol or progesterone prevented the increase in splenic weight and reduced the splenocyte yield to values significantly lower than that in sham-OVX rats. Both the treatments completely abolished the effect of ovariectomy on the size of TCR alpha beta- cell population, but had differential effects on that of TCR alpha beta+ cell population; estradiol did not affect its size, while progesterone caused a reduction on the account of a decrease in the numbers of both CD4+ and CD8+ cells. The results suggest that: a) estradiol and progesterone have similar effects on the size of the splenic B cell population and that replacement of either estradiol or progesterone can prevent the effects of ovariectomy on the size of this population and b) estradiol does not affect while progesterone reduces the size of splenic T cell population. Thus, replacement of none of them is able to compensate the removal of gonads.

Animals↗
PubMed2002

Hormone replacement therapy use over a decade in an Australian population.

OBJECTIVES: To describe the prevalence of hormone replacement therapy (HRT) during the 1990s in an Australian population and the length of time this therapy has been used. Design Data were obtained from five biennial representative population face-to-face interview surveys of the South Australian population from 1991 to 2000, and an additional telephone survey in 2001. The main surveys used consistent methods and quality control procedures. PARTICIPANTS: Over 3000 South Australian adults were interviewed in their own homes by trained health interviewers in each of the biennial surveys. RESULTS: In 2000, 28% of women aged over 50 were currently using HRT, and ever-use of HRT was 43%. Highest use of HRT was in the 55-59-year age group, where current use was 47% and ever-use was 70%. Among women 55 years and older there was a statistically significant increase in the prevalence of HRT use between 1991 and 2000. Mean length of use in women aged over 55 years increased from 5.4 years in 1991 to 9.6 years in 2000. CONCLUSIONS: Consistent surveillance of the population has shown that HRT use has not increased before age 55, but has greatly increased thereafter. Long-term effects may now be occurring, and further results of current long-term randomized trials are awaited to confirm the overall risk/benefit ratio suggested by observational studies and early results from long-term trials.

Adult↗
PubMed2001

Association between hospital and surgeon procedure volume and outcomes of total hip replacement in the United States medicare population.

BACKGROUND: The mortality and complication rates of many surgical procedures are inversely related to hospital procedure volume. The objective of this study was to determine whether the volumes of primary and revision total hip replacements performed at hospitals and by surgeons are associated with rates of mortality and complications. METHODS: We analyzed claims data of Medicare recipients who underwent elective primary total hip replacement (58,521 procedures) or revision total hip replacement (12,956 procedures) between July 1995 and June 1996. We assessed the relationship between surgeon and hospital procedure volume and mortality, dislocation, deep infection, and pulmonary embolus in the first ninety days postoperatively. Analyses were adjusted for age, gender, arthritis diagnosis, comorbid conditions, and income. Analyses of hospital volume were adjusted for surgeon volume, and analyses of surgeon volume were adjusted for hospital volume. RESULTS: Twelve percent of all primary total hip replacements and 49% of all revisions were performed in centers in which ten or fewer of these procedures were carried out in the Medicare population annually. In addition, 52% of the primary total hip replacements and 77% of the revisions were performed by surgeons who carried out ten or fewer of these procedures annually. Patients treated with primary total hip replacement in hospitals in which more than 100 of the procedures were performed per year had a lower risk of death than those treated with primary replacement in hospitals in which ten or fewer procedures were performed per year (mortality rate, 0.7% compared with 1.3%; adjusted odds ratio, 0.58; 95% confidence interval, 0.38, 0.89). Patients treated with primary total hip replacement by surgeons who performed more than fifty of those procedures in Medicare beneficiaries per year had a lower risk of dislocation than those who were treated by surgeons who performed five or fewer of the procedures per year (dislocation rate, 1.5% compared with 4.2%; adjusted odds ratio, 0.49; 95% confidence interval, 0.34, 0.69). Patients who had revision total hip replacement done by surgeons who performed more than ten such procedures per year had a lower rate of mortality than patients who were treated by surgeons who performed three or fewer of the procedures per year (mortality rate, 1.5% compared with 3.1%; adjusted odds ratio, 0.65; 95% confidence interval, 0.44, 0.96). CONCLUSIONS: Patients treated at hospitals and by surgeons with higher annual caseloads of primary and revision total hip replacement had lower rates of mortality and of selected complications. These analyses of Medicare claims are limited by a lack of key clinical information such as operative details and preoperative functional status.

Arthroplasty, Replacement, Hip↗
PubMed2004

Spatially structured population dynamics in feral oilseed rape.

We studied the population dynamics of feral oilseed rape (Brassica napus) for 10 years (1993-2002) in 3658 adjacent permanent 100 m quadrats in the verges of the M25 motorway around London, UK. The aim was to determine the relative importance of different factors affecting the observed temporal patterns of population dynamics and their spatial correlations. A wide range of population dynamics was observed (downward or upward trends, cycles, local extinctions and recolonizations), but overall the populations were not self-replacing (lambda < 1). Many quadrats remained unoccupied throughout the study period, but a few were occupied at high densities for all 10 years. Most quadrats showed transient oilseed rape populations, lasting 1-4 years. There were strong spatial patterns in mean population density, associated with soil conditions and the successional age of the plant community dominating the verge, and these large-scale spatial patterns were highly consistent from year to year. The importance of seed spilled from trucks in transit to the processing plant at Erith in Kent was confirmed: rape populations were significantly higher on the 'to Erith' verge than the 'from Erith' verge (overall mean 2.83-fold greater stem density). Quadrats in which lambda > 1 were much more frequent in the 'to Erith' verge, indicating that seed immigration can give the spurious impression of self-replacing population dynamics in time-series analysis. There was little evidence of a pervasive Moran effect, and climatic forcing did not produce widespread large-scale synchrony in population dynamics for the motorway as a whole; just 23% of quadrats had significant rank correlations with the mean time-series. There was, however, significant local spatial synchrony of population dynamics, apparently associated with soil disturbance and seed input. This study draws attention to the possibility that different processes may impose population synchrony at different scales. We hypothesize that synchrony in this system is driven by at least three processes: small-scale, local forcing caused by soil disturbance, intermediate-scale forcing as a result of seed input, and large-scale climatic forcing (e.g. winter rainfall) that affects the motorway as a whole.

Brassica napus↗
PubMed1997

Hormone replacement therapy and risk of venous thromboembolism: population based case-control study.

OBJECTIVE: To evaluate the association between use of hormone replacement therapy and the risk of idiopathic venous thromboembolism. DESIGN: Population based case-control study. SETTING: Population enrolled in the General Practice Research Database, United Kingdom. SUBJECTS: A cohort of 347,253 women aged 50 to 79 without major risk factors for venous thromboembolism was identified. Cases were 292 women admitted to hospital for a first episode of pulmonary embolism or deep venous thrombosis; 10,000 controls were randomly selected from the source cohort. MAIN OUTCOME MEASURES: Adjusted relative risks estimated from unconditional logistic regression. RESULTS: The adjusted odds ratio of venous thromboembolism for current use of hormone replacement therapy compared with non-users was 2.1 (95% confidence interval 1.4 to 3.2). This increased risk was restricted to first year users, with odds ratios of 4.6 (2.5 to 8.4) during the first six months and 3.0 (1.4 to 6.5) 6-12 months after starting treatment. No major risk differences were observed between users of low and high doses of oestrogens, unopposed and opposed treatment, and oral and transdermal preparations. The risk of idiopathic venous thromboembolism among non-users of replacement therapy was estimated to be 1.3 per 10,000 women per year. Among current users, idiopathic venous thromboembolism occurs at two to three times the rate in non-users, resulting in one to two additional cases per 10,000 women per year. CONCLUSIONS: Current use of hormone replacement therapy was associated with a higher risk of venous thromboembolism, although the risk seemed to be restricted to the first year of use.

Aged↗
PubMed1989

[Perioperative risks and problems in total hip joint replacement].

In a population of 689 patients with primary total hip arthroplasties, perioperative problems and complications were investigated. A preoperative cardiovascular disease was found in 32%, obesity in 18% of the patients. The death-rate was 0.43% in a population of patients, two thirds of whom was older than 60 years, one third even older than 70 years. The importance in preoperative evaluation of health and in treatment of various diseases is emphasized. Postoperative management is crucial to reduce thromboembolisms, urinary retention and infections.

Aged↗
PubMed2000

Field tests of environmentally friendly malathion replacements to suppress wild Mediterranean fruit fly (Diptera: Tephritidae) populations.

This article reports a large-scale field test of two environmentally friendly malathion replacements on wild populations of the Mediterranean fruit fly, Ceratatis capitata (Wiedemann): spinosad, a bacteria-derived toxin, and phloxine B, a red dye with phototoxic properties. The comparison test was conducted on 11 coffee fields infested with wild populations of Mediterranean fruit fly on the Hawaiian island of Kauai with 8-wk protein bait sprays with and without toxicants. To assess effectiveness, adults were trapped and larval infestation levels were evaluated with fruit collections. Malathion was found to be the most effective treatment. However, the two replacements gave significant levels of control, and because they are environmentally safer, should be considered for eradicating incipient populations of this invasive species of fruit fly. Cage tests were also conducted to ensure that the wild flies consumed the bait and to assess how long the bait-toxicant combination remained effective in the field. Although spinosad and phloxine B were found to be effective up to 1 wk, malathion remained effective at least 2 wk.

Animals↗
PubMed2001

Has oral fluid the potential to replace serum for the evaluation of population immunity levels? A study of measles, rubella and hepatitis B in rural Ethiopia.

OBJECTIVE: To assess the suitability of using oral-fluid samples for determining the prevalence of immunity to vaccine-preventable infections. METHODS: Paired blood and oral-fluid samples were obtained from 853 individuals of all ages from a rural Ethiopian community. Oral fluid around the gums was screened for measles- and rubella-specific antibodies using enhanced IgG antibody capture (GAC) enzyme-linked immunosorbent assays (ELISAs), and for anti-HBc antibodies using a prototype GACELISA. IgG antibodies in serum to measles, rubella and HBc were determined using commercial ELISAs. FINDINGS: Relative to serum, oral fluid assay sensitivity and specificity were as follows: 98% and 87% for measles, 79% and 90% for rubella, and 43% and 87% for anti-HBc. These assay characteristics yielded population prevalence estimates from oral fluid with a precision equal to that of serum for measles (all ages) and rubella (ages < 20 years). CONCLUSION: Our results suggest that oral fluid could have the potential to replace serum in IgG antibody prevalence surveys. Further progress requires assessment of variation in assay performance between populations as well as the availability of standardized, easy to use assays.

Adolescent↗
PubMed1993

[Attitudes toward estrogen replacement therapy. Study conducted on a sample population of women attending an ambulatory care center for the treatment of menopause].

Hormonal Replacement Therapy (HRT) is the most effective treatment of menopausal disturbances and has an established role in reducing the cardiovascular risk and in preventing the postmenopausal osteoporosis. Nevertheless several reports have evidenced that compliance with hormonal replacement therapy was not as good as expected, and that physician's and women's opinions can strongly influence the HRT choice, and the continuation of HRT use. The aim of this study was to assess the opinions and the expectations of menopausal women toward HRT. PATIENT AND METHODS. We utilized a questionnaire exploring social and affective conditions, and in particular women's opinions and experiences on menopause, hormonal therapy, the possibility of information, the reasons for accepting or refusing hormonal therapy. The questionnaires were administered to 226 menopausal clinic patients (Menopausal age: 2-10 years) in spontaneous menopause. RESULTS. 28% of the women were taking HRT at the time of the survey. Worries about menopause were reported by 27.4% of the group; this percentage was similar in both user and non-user groups. 70% received information on HRT from family doctors, and 63% from mass-media or conversations. 70% believes that the main problem of menopause is osteoporosis, and its prevention represents the most frequent aim that patients feel can be achieved by HRT. 67.5% of the group is afraid that long term treatment can be dangerous, however only 57% asked for detailed information to the doctor. To the question "Are you informed that HRT can reinduce menstrual bleeding?", 57.5% of the patients answered yes; 30% considered it to be a problem. CONCLUSIONS. Our study was carried out in a menopausal clinic and this can influence the answers of the respondents. Most women received some information on HRT, but their knowledge was only partial and did not eliminate the unrational fear of hormone therapy. Although long term use of HRT is to prevent CVD and menopausal osteoporosis, many of our patients specifically asked for treatment to be as short as possible. Women expectations's towards HRT are mainly referred to osteoporosis prevention and treatment: this may be explained by the high frequency of osteoarticular pain found in our patients; nevertheless it is possible that the more rational fear of osteoporosis hides the unconscious fear of a dramatic physical breakdown caused by the menopause. Detailed information to family doctors, to specialists, and to patients along with a further improvement of therapeutic regimens will allow a greater diffusion of HRT, bringing its short and long term benefits to an increasing number of women.

Estrogen Replacement Therapy↗