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1.
Perspect Public Health ; : 17579139231170784, 2023 Jun 18.
Article in English | MEDLINE | ID: mdl-37332258

ABSTRACT

AIMS: To review the barriers and facilitators that cross-sector partners face in promoting physical activity. METHODS: We searched Medline, Embase, PsychINFO, ProQuest Central, SCOPUS and SPORTDiscus to identify published records dating from 1986 to August 2021. We searched for public health interventions drawn from partnerships, where the partners worked across sectors and their shared goal was to promote or increase physical activity through partnership approaches. We used the Critical Appraisal Skills Programme UK (CASP) checklist and Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tool to guide the critical appraisal of included records, and thematic analysis to summarise and synthesise the findings. RESULTS: Findings (n = 32 articles) described public health interventions (n = 19) aiming to promote physical activity through cross-sector collaboration and/or partnerships. We identified barriers, facilitators and recommendations in relation to four broad themes: approaching and selecting partners, funding, building capacity and taking joint action. CONCLUSION: Common challenges that partners face are related to allocating time and resources, and sustaining momentum. Identifying similarities and differences between partners early on and building good relationships, strong momentum and trust can take considerable time. However, these factors may be essential for fruitful collaboration. Boundary spanners in the physical activity system could help translate differences and consolidate common ground between cross-sector partners, accelerating joint leadership and introducing systems thinking. PROSPERO REGISTRATION NUMBER: CRD42020226207.

3.
Water Sci Technol ; 61(4): 885-90, 2010.
Article in English | MEDLINE | ID: mdl-20182066

ABSTRACT

Waste stabilisation ponds (WSP) are efficient, cost-effective methods of treating wastewater in rural and remote communities in Australia. It is recognised that sunlight plays a significant role in their disinfection, however, due to the poor penetration of light in turbid waters it has been hypothesised that other mechanisms may also contribute to disinfection in WSPs. To date, studies have reported various and conflicting results with regards to the relative contributions of UVA, UVB, PAR and environmental factors including pH, DO and photo-sensitisers on micro-organism disinfection. Initially we investigated the role of these environmental factors on the solar disinfection of enterococci in buffered distilled water to control for potential confounding factors within the wastewater. Die-off rate constants were measured, in sterile buffered distilled water at varying pH and dissolved oxygen concentrations, for enterococci irradiated with UVA and UVB. Enterococci were found to be predominantly inactivated by UVB (p<0.001), however, UVA was also observed to increase inactivation rates relative to the dark control (p<0.001). DO and pH were found to have no effect on inactivation rate when enterococci were irradiated with UVB (p>0.05), however, when irradiated with UVA, both DO and pH were observed to further increase inactivation rates (p<0.01).


Subject(s)
Enterococcus/metabolism , Sunlight , Water Microbiology , Water Pollutants/isolation & purification , Water Purification/methods , Humic Substances , Hydrogen-Ion Concentration , Light , Nephelometry and Turbidimetry , Oxygen/chemistry , Oxygen/metabolism , Photosensitizing Agents/pharmacology , Ultraviolet Rays , Waste Disposal, Fluid/methods , Water/chemistry
4.
J Appl Microbiol ; 109(1): 239-47, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20070443

ABSTRACT

AIMS: To investigate the role of heterotrophic bacteria in the corrosion of galvanized steel in the presence of water. METHODS AND RESULTS: Samples were taken from corroding galvanized steel pipes conveying water for specialist applications, and heterotrophic bacteria were isolated and cultured. The majority of bacteria were Gram-negative aerobes and included Pseudomonas sp., Bacillus pumilus, Afipia spp. and Blastobacter denitrificans/Bradyrhizobium japonicum. Zinc tolerance was assessed through growth and zinc disc diffusion experiments. In general, zinc negatively influenced growth rates. An unidentified yeast also isolated from the system demonstrated a high tolerance to zinc at concentrations up to 4 g l(-1) . Coupon experiments were performed to assess corrosion by the bacteria on galvanized steel and steel coupons. The majority of isolates as pure culture biofilms (69%) accelerated corrosion of galvanized coupons, assessed as zinc release, relative to sterile control coupons (P < 0·05). Pure culture biofilms did not increase the corrosion of steel, with four isolates demonstrating protective effects. CONCLUSIONS: Pure culture biofilms of heterotrophic bacteria isolated from a corroding galvanized pipe system were found to accelerate the corrosion of galvanized steel coupons. SIGNIFICANCE AND IMPACT OF THE STUDY: Microbially influenced corrosion is a potential contributor to sporadically occurring failures in galvanized steel systems containing water. Management strategies should consider microbial control as a means for corrosion prevention in these systems.


Subject(s)
Bacteria/isolation & purification , Biofilms , Steel , Water Microbiology , Water Supply , Bacteria/genetics , Bacteria/growth & development , Corrosion , Heterotrophic Processes , RNA, Ribosomal, 16S/genetics , Steel/chemistry , Zinc/chemistry
5.
Int J STD AIDS ; 19(3): 168-71, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18397556

ABSTRACT

The aim of this study was to investigate the incidence of reinfection with sexually transmitted infection (STI) and its possible predicting factors among patients reattending a department of genitourinary (GU) medicine. The method included a retrospective study on consecutive patients re-screened for STI in a busy department of GU medicine between January 1996 and April 2005. Cox regression model was used to investigate the association of age, gender, sex group, previous STI, counselling for an STI on the last attendance, number of sexual partners in the previous attendance episode, condom use and the number for partners with whom they had unprotected sex, with STI at current screening. The results show that 302 consecutive patients with more than two attendance episodes were included in the study. Patients were mostly women (92%), younger than 35 years (80%) and heterosexual (98%). At baseline, 70 (23%) patients had STI. The incidence density of STI at the end of follow-up period was 15.69/100 person-years. Testing positive for an STI was associated with age younger than 25 years (hazard ratio 2.70 [95% confidence interval 1.70-4.57]; P = 0.000). In conclusion, our study confirmed the improvement in access to GU medicine services, encouragement of patients with an STI for re-screening on regular basis and use of novel STI counselling strategies, especially for younger patients may reduce the incidence of subsequent STI.


Subject(s)
Ambulatory Care/statistics & numerical data , Counseling , Sexually Transmitted Diseases/epidemiology , Sexually Transmitted Diseases/prevention & control , Adult , Ambulatory Care Facilities/statistics & numerical data , Demography , Female , Humans , Incidence , Male , Proportional Hazards Models , Recurrence , Risk Factors , Sexually Transmitted Diseases/diagnosis , Urogenital System
6.
Am J Ophthalmol ; 129(5): 599-607, 2000 May.
Article in English | MEDLINE | ID: mdl-10844050

ABSTRACT

PURPOSE: To measure peripapillary retinal nerve fiber layer volume in normal subjects and patients with ocular hypertension, primary open-angle glaucoma, and low-tension glaucoma. METHODS: Sixty-five subjects were classified into four groups of normal subjects and subjects with ocular hypertension, primary open-angle glaucoma, and low-tension glaucoma on the basis of intraocular pressure measurements, visual field loss, and optic disk appearance. Groups were matched for sex, age, and optic disk area. Peripapillary retinal nerve fiber layer volume measurements were made with a modification of software version 1.11 of the Heidelberg Retina Tomograph confocal scanning laser ophthalmoscope. Retinal nerve fiber layer volume measurements were taken at 0.1-mm increments from the disk margin for a global 360-degree assessment and at four predefined segments using two different reference planes. Statistical analysis was carried out using analysis of variance with Bonferroni correction. RESULTS: Retinal nerve fiber layer volume measurements showed a gradation from normal to ocular hypertension and from ocular hypertension to glaucoma groups. Mean group measurements showed statistically significant differences (P <.05) in peripapillary retinal nerve fiber layer volume for most segmental measures between the groups. Measurements with the default reference plane in the 0.0-mm to 0.1-mm and 0.1-mm to 0.2-mm increments for the superotemporal segment showed the greatest differences between groups (P <.00005). CONCLUSION: Peripapillary retinal nerve fiber layer volume measurements differ between groups of normal subjects and patients with ocular hypertension, primary open-angle glaucoma, and low-tension glaucoma. This measure offers a further method of assessment of retinal nerve fiber layer in patients with glaucoma and glaucoma suspects.


Subject(s)
Glaucoma, Open-Angle/diagnosis , Nerve Fibers/pathology , Ocular Hypertension/diagnosis , Ocular Hypotension/diagnosis , Optic Disk/pathology , Retinal Ganglion Cells/pathology , Aged , Female , Humans , Intraocular Pressure , Male , Middle Aged , Ophthalmoscopy , Tomography/methods , Visual Fields
7.
J Glaucoma ; 5(4): 241-5, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8795768

ABSTRACT

PURPOSE: The cup-to-disc ratio is a widely used clinical measure of optic nerve damage in the management of glaucoma patients and those suspected of having glaucoma. Knowledge of the optic disc size allows for a better assessment of the clinical significance of the cup-to-disc ratio. In this study, two optical methods-slit-lamp biomicroscopy and confocal scanning laser ophthalmoscopy-were used to measure the vertical disc diameter as an indirect measure of optic disc size. The aim was to provide a simple and clinically useful examination technique in the management of glaucoma. METHODS: The vertical optic disc diameter was measured with aspheric lenses (Volk 60, 78, and 90 D, and Nikon 60 and 90 D) using slit-lamp biomicroscopy in 25 emmetropic normal volunteers. The average of three readings was determined for each of the lenses and the measurements were correlated with the magnification-corrected diameter measured with the Heidelberg Retina Tomograph. RESULTS: The mean vertical disc diameter of the group, as measured with the Heidelberg Retina Tomograph, was 1.81 +/- 0.18 mm. Results obtained with the lower-power lenses correlated best with the Heidelberg Retina Tomograph measurements (for example, Volk 60 D: r = 0.80, p = 0.0001, 95% confidence interval 1.76-1.85 mm), whereas the 90-D correlation was the weakest (for example, Volk 90 D: r = 0.59. p = 0.002, 95% confidence interval 1.75-1.87 mm). With the Volk 60-D lens, the "best fit" equation for estimating disc diameter, in millimetres, is Y = 0.85X + 0.06, where Y is the Heidelberg Retina Tomograph value and X is the slit-lamp biomicroscopy measurement. CONCLUSION: Using these formulae, the clinician is able to estimate the optic disc diameter with sufficient accuracy to allow clinical decisions to be made in the evaluation of patients with glaucoma, without recourse to expensive technology.


Subject(s)
Glaucoma/pathology , Optic Disk/pathology , Adult , Glaucoma/diagnosis , Humans , Microscopy, Confocal , Middle Aged , Ophthalmology/methods , Tomography
8.
J Rural Stud ; 6(1): 29-43, 1990.
Article in English | MEDLINE | ID: mdl-12282965

ABSTRACT

The change from depopulation to population increase in the more remote rural areas of England is analyzed using data from a survey of 300 households in North Devon. The heterogeneous nature of the migrants and their reasons for migration are stressed. "The reasons for leaving the former area of residence tended to relate to lifestyle, personal or environmental factors whereas the reasons for choosing North Devon were more often about jobs and house prices. This complexity and diversity clearly makes difficult the quest for a single theory of the repopulation process."


Subject(s)
Emigration and Immigration , Motivation , Population Dynamics , Population Growth , Rural Population , Transients and Migrants , Behavior , Demography , Developed Countries , England , Europe , Population , Population Characteristics , Psychology , United Kingdom
9.
Acta Vet Scand ; 31(4): 459-69, 1990.
Article in English | MEDLINE | ID: mdl-2099624

ABSTRACT

Changes in consecutive estimates of milk progesterone concentrations and serum steroid hormone and sex hormone-binding globulin (SHBG) concentrations in the postpartum period were examined in Finnish Ayrshire and Friesian dairy cows which were divided according to feeding into a hay group and a silage group. Milk progesterone concentrations rose above 10 nmol/l, indicating the start of ovarian luteal activity, slightly earlier in the silage group (28.4 +/- 8.7 (S.D.) days, n = 19) than in the hay group (33.4 +/- 10.3, n = 28) after calving. Likewise, the first normal oestrous cycles began slightly earlier in cows fed with silage. On the other hand, no differences in the beginning of ovarian luteal activity were observed between the breeds. Serum oestradiol-17 beta, oestrone, testosterone, 5 alpha-dihydrotestosterone (5 alpha-DHT), pregnenolone and progesterone concentrations were fairly unchanged during postpartum anoestrus after uterine involution and before ovarian cyclic activity. After first ovulation, considerable increases in milk and serum progesterone concentrations were observed. The increase was accompanied by elevations in serum pregnenolone and 5 alpha-DHT concentrations. In the late luteal phase, progesterone, 5 alpha-DHT and pregnenolone concentrations rapidly declined, leading to low hormone levels in pro-oestrus. Thereafter, serum pregnenolone and 5 alpha-DHT concentrations slightly increased during the follicular phase. On the other hand, oestradiol-17 beta concentrations were elevated in pro-oestrus and decreased after that, being lowest at met-oestrous. Serum testosterone concentrations appeared to be unchanged during postpartum anoestrus and over the oestrous cycle. Serum SHBG concentrations were unchanged during postpartum anoestrus and over the oestrous cycle, as well as in pregnant animals. The serum SHBG concentrations were about double those found in women with normal menstrual cycles, whereas oestradiol concentrations were much lower. At present, it cannot be explained how the biological effects of oestradiol become evident under such conditions.


Subject(s)
Estrus/blood , Gonadal Steroid Hormones/blood , Postpartum Period/blood , Sex Hormone-Binding Globulin/analysis , Anestrus/blood , Animals , Female
10.
Clin Endocrinol (Oxf) ; 31(2): 201-7, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2605795

ABSTRACT

The concentrations of sex hormone-binding globulin (SHBG) and testosterone (T) were measured in the cord blood of full-term newborns (14 boys, 15 girls) and pre-term newborns (10 boys, 5 girls), and in the venous circulation of 100 full-term infants aged 1-204 days. The ratio of T to SHBG (the 'free androgen index', FAI) was calculated to reflect the level of unbound T (the free, biologically active fraction). In boys' umbilical cord sera, T concentrations were significantly greater in arterial than in venous sera, while there was no such difference in the concentration of SHBG. Levels of SHBG in cord sera were considerably lower than those seen in the maternal circulation at term, but they were significantly greater in boys' than in girls' cord sera. Levels of T, and the FAI, were significantly greater in boys' arterial cord sera than in girls'. In early infancy, SHBG concentrations rose in both sexes, the highest values being seen in girls. In infant girls, levels of T and the FAI were constantly low. In infant boys, the expected peak in serum T concentrations was observed at 1-3 months the values approaching those seen in men. In contrast, values of the FAI at this age were relatively low, similar to those seen in women. This suggests that the elevation of male serum T during the first months of life lacks biological significance. However, it is important to realise that the FAI in male infants is about one order of magnitude larger than that in female infants at this time.


Subject(s)
Infant, Newborn/blood , Sex Hormone-Binding Globulin/analysis , Testosterone/blood , Androgens/metabolism , Female , Humans , Infant , Male
12.
Clin Chem ; 34(1): 63-6, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3338188

ABSTRACT

A time-resolved immunofluorometric assay (trlFMA) for human sex-hormone binding globulin (SHBG) is described in which antibody-coated tubes or microliter strip-wells and a europium (Eu) chelate-labeled monoclonal antibody are used. The trlFMA sensitivity is similar to that of other SHBG immunoassays, and other analytical variables compare favorably with an SHBG immunoradiometric assay (IRMA) kit and a steroid binding capacity assay: the interassay coefficient of variation (CV) is less than 8% and the intra-assay CV is less than 6% for concentrations between 6 and 200 nmol/L. The reference intervals (means +/- SD) for SHBG concentrations (nmol/L) in serum from 10 men, 10 women, and 10 pregnant women were 23 +/- 12, 65 +/- 39, and 439 +/- 122, respectively. In 14 hirsute women the mean +/- SD serum SHBG concentration (37 +/- 21 nmol/L) was significantly lower (P less than 0.01) than the mean for an age-matched, nonhirsute female comparison group. The trlFMA is technically simple, requires no centrifugation or separation reagent, and takes a counting time of only 1 s. In addition, the Eu-label is nontoxic, presents no waste-disposal problems, and has a long shelf life.


Subject(s)
Europium , Immunoassay , Sex Hormone-Binding Globulin/analysis , Adult , Female , Fluorescent Dyes , Fluorometry , Hemolysis , Humans , Hyperlipidemias , Male , Pregnancy , Quality Control , Reference Values
13.
Prostate ; 9(2): 159-67, 1986.
Article in English | MEDLINE | ID: mdl-2428021

ABSTRACT

Twenty-one samples of surgically removed benign prostatic hypertrophy (BPH) were brought to the laboratory either in an insulated container (ambient temperature) or on ice. They were cleaned and roughly minced at room temperature. In 18 cases, samples of up to 1 g were kept at various temperatures (4 degrees C, c. 20 degrees C, and 37 degrees C) for up to 77 h; some were taken for storage (-70 degrees C) at the beginning and others at various times within this period. In three cases, portions of tissue were incubated in liquid medium in the absence and presence of testosterone. The concentrations of six androgens (testosterone, 5 alpha-dihydrotestosterone (5 alpha-DHT), 5 alpha-androstane-3 alpha, 17 beta-diol, androstenedione, 5 alpha-androstanedione, and androsterone) were measured by radioimmunoassays. The results indicated that in conditions resembling those after death, the BPH tissue content of 5 alpha-DHT falls to a variable degree, while concentrations of 5 alpha-androstane-3 alpha, 17 beta-diol, 5 alpha-androstanedione, and androsterone increase. After 2 to 3 days, the 5 alpha-DHT concentrations remained greater than those reported previously from this laboratory (and others) in normal prostate tissue removed at autopsy.


Subject(s)
Androgens/analysis , Prostate/analysis , Prostatic Hyperplasia/metabolism , Aged , Humans , Male , Middle Aged , Specimen Handling , Temperature , Time Factors
14.
J Steroid Biochem ; 23(1): 33-8, 1985 Jul.
Article in English | MEDLINE | ID: mdl-3160892

ABSTRACT

The influence of high doses of testosterone and anabolic steroids on testicular endocrine function and on circulating steroid binding proteins, sex hormone binding globulin (SHBG) and cortisol binding globulin (CBG), were investigated in power athletes for 26 weeks of steroid self-administration and for the following 16 weeks after drug withdrawal. Serum testosterone and androstenedione concentrations increased (P less than 0.05) but pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone, 5-androstene-3 beta, 17 beta-diol, progesterone and 17-hydroxyprogesterone concentrations strongly decreased (P less than 0.001) during steroid administration. Serum pregnenolone, 17-hydroxypregnenolone and dehydroepiandrosterone sulphate concentrations followed the changes of the corresponding unconjugated steroids but 5-androstene-3 beta, 17 beta-diol and testosterone sulphate concentrations remained unchanged during the follow-up time. During drug administration SHBG concentrations decreased by about 80 to 90% and remained low even for the 16 weeks following steroid withdrawal. Steroid administration had no influence on serum CBG concentrations. In conclusion, self-administration of testosterone and anabolic steroids soon led to impairment of testicular endocrine function which was characterized by low concentrations of testosterone precursors, high ratios of testosterone to its precursor steroids and low SHBG concentrations. Decreased concentrations of SHBG and testicular steroids were still partly evident during the 16 weeks after drug withdrawal. The depressed circulating levels of dehydroepiandrosterone and its sulphate may indicate that the androgenic-anabolic steroids also suppress adrenal androgen production.


Subject(s)
Anabolic Agents/pharmacology , Androgens/blood , Carrier Proteins/metabolism , Sex Hormone-Binding Globulin/metabolism , Testosterone/pharmacology , 17-alpha-Hydroxypregnenolone/blood , Anabolic Agents/administration & dosage , Androstenediol/blood , Androstenedione/blood , Dehydroepiandrosterone/analogs & derivatives , Dehydroepiandrosterone/blood , Dehydroepiandrosterone Sulfate , Humans , Kinetics , Male , Pregnenolone/blood , Progesterone/blood , Sports , Testosterone/administration & dosage , Testosterone/blood
15.
J Steroid Biochem ; 22(4): 481-5, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3999743

ABSTRACT

Small pieces (10-20 mg) of human testis tissue were incubated for 4 h in the presence or absence of hCG and 8-bromo-cAMP and the concentrations of testosterone, some of its steroidal precursors, and their sulphates were measured by radioimmunoassays. The results showed, we believe for the first time, that the production of steroid sulphates as well as of unconjugated steroids can be stimulated in human testis tissue in vitro and they confirm earlier observations in vivo which suggested that testicular production of steroid sulphates can be stimulated by hCG.


Subject(s)
8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Chorionic Gonadotropin/pharmacology , Steroids/biosynthesis , Testis/drug effects , Aged , Humans , Male , Middle Aged , Radioimmunoassay , Sulfates , Testis/metabolism , Time Factors
16.
Prostate ; 6(4): 417-22, 1985.
Article in English | MEDLINE | ID: mdl-3937150

ABSTRACT

Six patients with advanced prostatic carcinoma were treated with tamoxifen (2 X 20 mg daily) for up to 3 months before orchiectomy. Blood samples for gonadotropin, sex steroid, and prostate-specific acid phosphatase (PAP) determinations were taken before tamoxifen treatment, daily for 1 week, and at monthly intervals. Steroid concentrations in the testis tissue and spermatic vein blood were assayed from samples taken at orchiectomy. No consistent changes were observed during tamoxifen treatment, although there was a transient drop in the mean concentrations of LH on days 3 and 4 of treatment. The circulating concentrations of estradiol tended to be increased at 1, 2, and 3 months of treatment. The spermatic vein concentrations of testosterone and its precursors tended to be higher than those in nontreated prostatic carcinoma patients previously reported from this laboratory, indicating slight stimulation of testicular steroidogenesis. There were no changes in circulating levels of PAP and no improvement in clinical condition, indicating that long-term tamoxifen administration is not effective in the treatment of prostate carcinoma.


Subject(s)
Gonadal Steroid Hormones/blood , Prostatic Neoplasms/drug therapy , Tamoxifen/administration & dosage , Aged , Follicle Stimulating Hormone/blood , Humans , Luteinizing Hormone/blood , Male , Middle Aged , Progestins/blood , Prostatic Neoplasms/blood , Tamoxifen/therapeutic use , Testis/metabolism
17.
Acta Endocrinol (Copenh) ; 107(3): 413-9, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6391059

ABSTRACT

Serum sex hormone binding globulin (SHBG) concentrations were measured by an immunoradiometric assay, as part of a longitudinal study of puberty in girls, and were related to age, pubertal stage, age at menarche, weight, nature of the menstrual cycle and serum concentrations of sex steroids. A slow but very significant decrease was seen in SHBG from 77 nmol/l at 8-10 years of age to about 50 nmol/l after 15 years of age. Serum SHBG concentrations showed weak negative correlations with those of androstenedione and testosterone during puberty. The closest associations found between SHBG and the parameters measured were negative correlations with weight and body fat percentage in both pre-menarcheal and post-menarcheal girls, even after the effect of age was accounted for by calculating partial correlation coefficients. Girls who experienced early menarche (before 13.0 years) had lower SHBG but higher oestradiol serum concentrations at 10.0-15.9 years of age compared to girls with later menarche. In ovulatory menstrual cycles, a significant increase in SHBG was found from the early to the late part of the cycle, whereas no changes took place in anovulatory cycles. Serum concentrations of SHBG showed positive correlations with those of oestradiol and progesterone in specimens taken in the late part of the cycle. In view of the weak relationships between serum SHBG and sex steroid concentrations, and the strong relationships between SHBG, weight and body fat percentage, factors other than steroids have to be considered in the regulation of SHBG levels during puberty.


Subject(s)
Menstrual Cycle , Puberty , Sex Hormone-Binding Globulin/metabolism , Adolescent , Age Factors , Body Weight , Child , Estradiol/blood , Female , Humans , Immunologic Techniques , Longitudinal Studies , Menarche , Ovulation , Radiometry
18.
Kidney Int ; 26(3): 308-18, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6542606

ABSTRACT

Aztreonam, a new monobactam, will be widely used because of its broad aerobic gram-negative bacterial coverage and its apparent low risk of allergic phenomena in penicillin/cephalosporin-sensitive patients. We examined aztreonam kinetics in patients during hemodialysis and in the interdialytic period and in patients on continuous ambulatory peritoneal dialysis (CAPD), and related aztreonam to urea clearance (CL). In hemodialysis patients, aztreonam serum half-life was 7.9 hr between and 2.7 hr during dialysis sessions. CLserum, CLrenal, and CLother were 24.4, 0.5, and 23.9 ml/min, respectively, during the interdialytic period. Four hours of dialysis removed 38.2% (range, 27 to 58%) of antibiotic. CL of aztreonam by hemodialysis was 36.6 to 43.2 ml/min, 50 to 77% greater than interdialytic CL. CL of urea by hemodialysis was 112.4 to 115.6 ml/min; CLaztreonam/CLurea ratio was 0.28 to 0.33 during the hemodialysis sessions. During CAPD, aztreonam serum half-life after intravenous dosing was 7.1 hr; dialysate recovery, 9.7% of the dose; CLserum, CLrenal, CLperitoneal dialysis, and CLother were 23.8, 0.5, 2.1, and 21.3 ml/min, respectively. CLurea by CAPD was 6.5 ml/min. Thus, CLaztreonam during CAPD was 32% of CLurea. Aztreonam was detectable in dialysate at 48 hr (eight exchanges) after peritoneal administration in the first exchange. Hemodialysis and CAPD patients given aztreonam treatment should receive the standard dose of aztreonam as a loading dose, followed by one-fourth the loading dose at standard dose intervals. Hemodialysis patients should receive a supplemental dose equal to half their usual maintenance dose immediately after each dialysis session. For CAPD patients with peritonitis due to susceptible organisms, a 1-g i.v. loading dose followed by a 0.5-g i.p. dose every 6 hr is suggested. In any individual patient undergoing hemodialysis or CAPD, the relationship between CLurea and CLaztreonam should allow appropriate antibiotic dose adjustment.


Subject(s)
Anti-Bacterial Agents/metabolism , Kidney Failure, Chronic/metabolism , Peritoneal Dialysis, Continuous Ambulatory , Peritoneal Dialysis , Renal Dialysis , Adult , Anti-Bacterial Agents/blood , Aztreonam , Biological Availability , Female , Humans , Kinetics , Male , Mathematics , Metabolic Clearance Rate , Middle Aged , Time Factors , Urea/metabolism
19.
J Endocrinol ; 99(3): 409-14, 1983 Dec.
Article in English | MEDLINE | ID: mdl-6196427

ABSTRACT

Prostate tissues removed from patients with benign prostatic hypertrophy were separated into epithelial and stromal components and nuclei purified from these. The concentrations of testosterone, 5 alpha-dihydrotestosterone, 5 alpha-androstane-3 alpha,17 beta-diol, 4-androstene-3,17-dione, 5 alpha-androstanedione and androsterone in pooled preparations of the purified nuclei were determined by radioimmunoassays after the purification of solvent steroid extracts by Lipidex-5000 column chromatography. The most abundant androgen measured was 5 alpha-dihydrotestosterone and it was significantly (P less than 0.05) more concentrated in the stromal nuclei than in the epithelial nuclei. The mean concentration of androsterone was also significantly (P less than 0.05) greater in the stromal nuclei whereas that of testosterone was equal in the two nuclear types. The concentrations of 5 alpha-androstane-3 alpha,17 beta-diol, 4-androstene-3,17-dione and 5 alpha-androstanedione were below the sensitivity limits of the assays in the majority of cases, but the results indicated that when detectable the first two were more concentrated in the stromal than the epithelial nuclei. The results emphasize the importance of the prostatic stroma in androgen metabolism, and the relative concentrations of 5 alpha-dihydrotestosterone and testosterone indicated identical 5 alpha-reductase activities in the nuclei in comparison with respective whole cell epithelial and stromal preparations. 5 alpha-Dihydrotestosterone concentrations were clearly higher than the nuclear androgen receptor levels previously reported from this laboratory.


Subject(s)
Androgens/analysis , Prostate/analysis , Prostatic Hyperplasia/metabolism , Cell Nucleus/analysis , Dihydrotestosterone/analysis , Epithelium/analysis , Epithelium/ultrastructure , Humans , Male , Prostate/ultrastructure , Prostatic Hyperplasia/pathology , Testosterone/analysis
20.
J Steroid Biochem ; 19(2): 1147-51, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6224978

ABSTRACT

The responses of peripheral serum steroids to a single injection of hCG (80 IU/kg b wt) were compared in adult male rats and humans. Before hCG, the quantitatively dominating steroids were dehydroepiandrosterone, testosterone and 17-hydroxypregnenolone in the men, and testosterone and progesterone in the rats. One hour after hCG the concentrations of testosterone and all its precursors measured except for pregnenolone were significantly elevated in the rat serum, whereas a clear rapid response was not observed in the men. Transient blockade of C21 steroid side-chain cleavage was seen in both species at about 24-36 h after hCG, which occurred at the same time as the maximum concentration of estradiol in the men. No changes in rat serum estradiol concentrations were observed. Both species showed a secondary stimulation of testosterone and androstenedione formation at around 3 days. Our findings are compatible with the concept that the main difference in the gonadotropin-stimulated steroidogenesis in man and rat is the magnitude of the rapid steroidogenic response to hCG, which is very small in man and indicates smaller supply or lesser metabolism of mitochondrial cholesterol in human testis.


Subject(s)
17-alpha-Hydroxypregnenolone/blood , Androgens/blood , Chorionic Gonadotropin/pharmacology , Progesterone/blood , Adult , Animals , Dehydroepiandrosterone/blood , Humans , Kinetics , Male , Rats , Rats, Inbred Strains , Species Specificity , Testosterone/blood
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