Poor working conditions and work stress among Canadian sex workers.

BACKGROUND: While sex work is often considered the world's oldest profession, there remains a dearth of research on work stress among sex workers (SWs) in occupational health epidemiological literature. A better understanding of the drivers of work stress among SWs is needed to inform sex work policy, workplace models and standards. AIMS: To examine the factors that influence work stress among SWs in Metro Vancouver. METHODS: Analyses drew from a longitudinal cohort of SWs, known as An Evaluation of Sex Workers' Health Access (AESHA) (2010-14). A modified standardized 'work stress' scale, multivariable linear regression with generalized estimating equations was used to longitudinally examine the factors associated with work stress. RESULTS: In multivariable analysis, poor working conditions were associated with increased work stress and included workplace physical/sexual violence (ß = 0.18; 95% confidence interval (CI) 0.06, 0.29), displacement due to police (ß = 0.26; 95% CI 0.14, 0.38), working in public spaces (ß = 0.73; 95% CI 0.61, 0.84). Older (ß = -0.02; 95% CI -0.03, -0.01) and Indigenous SWs experienced lower work stress (ß = -0.25; 95% CI -0.43, -0.08), whereas non-injection (ß = 0.32; 95% CI 0.14, 0.49) and injection drug users (ß = 0.17; 95% CI 0.03, 0.31) had higher work stress. CONCLUSIONS: Vancouver-based SWs' work stress was largely shaped by poor work conditions, such as violence, policing, lack of safe workspaces. There is a need to move away from criminalized approaches which shape unsafe work conditions and increase work stress for SWs. Policies that promote SWs' access to the same occupational health, safety and human rights standards as workers in other labour sectors are also needed.

An unexpected counter-regulatory role of IL-10 in B-lymphocyte-mediated transplantation tolerance.

Monoclonal antibody against the CD45RB protein induces stable transplantation tolerance to multiple types of allograft. We have previously established that this tolerance protocol relies on the regulatory function of B lymphocytes for its effect. B lymphocytes have also been reported to participate in immune regulation in several other settings. In most of these systems, the regulatory function of B lymphocytes depends on the production of IL-10. Therefore, we investigated the role of IL-10 in the anti-CD45RB model of B-cell-mediated transplantation tolerance. Surprisingly, using antibody-mediated neutralization of IL-10, IL-10-deficient recipients and adoptive transfer of IL-10-deficient B lymphocytes, we found that IL-10 actually counter-regulates tolerance induced by anti-CD45RB. Furthermore, neutralization of IL-10 reduced the development of chronic allograft vasculopathy compared to anti-CD45RB alone and reduced the production of graft reactive alloantibodies. These data suggest that the participation of regulatory B lymphocytes in transplantation tolerance may be distinct from how they operate in other systems. Identifying the specific B lymphocytes that mediate transplantation tolerance and defining their mechanism of action may yield new insights into the complex cellular network through which antigen-specific tolerance is established and maintained.

Regulatory T-cell counter-regulation by innate immunity is a barrier to transplantation tolerance.

Innate immune signals foster adaptive immunity through activation of antigen-presenting cells. Recent in vitro evidence suggests that innate signaling may also contribute to immunity by countering the effects of regulatory T cells (T-regs), counter-regulation. We present in vivo evidence using a transgenic skin allograft model that the function of T-regs is lost in the setting of acute skin transplantation but remains intact when grafts were transplanted 1 month prior to allow surgery-induced inflammation to abate. Our findings identify T-reg counter-regulation as a naturally occurring process that accompanies transplantation and an important barrier to T-reg-mediated tolerance. Our finding further highlights the central role of regulatory cell deactivation in the initiation of the immune response.

Prevalence on beef carcasses of Mycobacterium avium subsp. paratuberculosis DNA.

Fifty samples were collected from each of skinned and dressed carcasses, from each of culled beef breeding cows and fed beef cattle <18 months old at two beef packing plants A and B, and from culled dairy cows at a packing plant C. The 450 samples were collected by swabbing an area of about 1000 cm2 in the anal region of each carcass. DNA extracted from each swab was tested for the IS900 and F57 sequences of the Mycobacterium avium subsp. paratuberculosis (MAP) genome by two stage, nested polymerase chain reaction (PCR) procedures. An internal amplification control (IAC) was detected in 45 or more of each group of 50 DNA preparations. IS900 and F57 were detected in some IAC-positive preparations from all and all but one of the groups of carcasses, respectively. Of the IAC-positive preparations in each group, between 6 and 54% were positive for IS900, and between 4 and 20% were positive for F57. When preparations were tested by single stage, quantitative PCR procedures, IS900 was detected in two samples but F57 was detected in none. The MAP DNA on carcasses was probably derived from small numbers of MAP from the environment that contaminated the animals' hides.

The effect of polyamines of DNA synthesis in vitro.

Nuclei and DNA-dependent polymerases alpha and beta were isolated from exponentially growing baby hamster kidney 21/C13 cells and were used to study the effects of polyamines on DNA synthesis in vitro. The greatest effect was observed with spermine, which inhibited both nuclear DNA synthesis and the activity of partially purified DNA polymerase alpha. At 2.5 mM spermine, the maximum concentration used, we observed 58 and 68% inhibition of DNA synthesis by isolated nuclei and polymerase alpha, respectively. In contrast, spermidine caused a small increase in nuclear DNA synthesis at low concentrations (0.5 mM) and inhibition at higher concentrations (2.5 mM); it had no significant effect on the partially purified polymerase alpha. Neither polyamine had any appreciable effect on polymerase beta activity. The results are consistent with the concept that DNA polymerase alpha catalyses the observed DNA synthesis in isolated nuclei.

Double Bond Position Plays an Important Role in Delta-9 Desaturation and Lipogenic Properties of Trans 18:1 Isomers in Mouse Adipocytes.

The objective of this research was to study the delta-9 desaturation of individual trans (t) fatty acids that can be found in ruminant fat or partially hydrogenated vegetable oils (PHVO) and determine their effects on lipogenic gene expression in adipocytes. It was hypothesized that delta-9 desaturation and lipogenic properties of t-18:1 isomers depend on the position of double bond. Differentiated 3T3-L1 adipocytes were treated with 200 µM of t6-18:1, t9-18:1, t11-18:1, t13-18:1 or t16-18:1, cis (c)-9 18:1 or bovine serum albumin (BSA) vehicle control for 48 h. Cells were then harvested for fatty acid and gene expression analyses using gas chromatography and quantitative PCR respectively. Among t-18:1 isomers, t13-18:1 and t11-8:1 had the greatest percent delta-9 desaturation (44 and 41 % respectively) followed by t16-18:1 and t6-18:1 (32 and 17 % respectively), while c9-18:1 and t9-18:1 did not undergo delta-9 desaturation. Trans9-18:1 up-regulated (P < 0.05) the expression of lipogenic genes including fatty acid synthase and stearoyl-CoA desaturase-1 (P < 0.05), whereas the expression of these genes were not affected with other t-18:1 isomers (P > 0.05). Consistent with gene expression results, t9-18:1 increased the de novo lipogenic index (16:0/18:2n-6) compared with control cells and increased delta-9 desaturation index (c9-16:1/18:0) compared to other t-18:1 isomers (P < 0.05). The current study provides further evidence that the predominant trans fatty acid in PHVO (t9-18:1) has isomer specific lipogenic properties.

Individual trans 18:1 isomers are metabolised differently and have distinct effects on lipogenesis in 3T3-L1 adipocytes.

The objective of this research was to study the metabolism of individual trans fatty acids (FAs) that can be found in ruminant fat or partially hydrogenated vegetable oils (PHVO) and determine their effects on FA composition and lipogenic gene expression in adipocytes. Differentiated 3T3-L1 adipocytes were treated with 200 µM of either trans-9-18:1, trans-11-18:1, trans-13-18:1, cis-9-18:1 or BSA vehicle control for 120 h. Trans-9-18:1 increased total cell FA content (µmole/well) compared to other FA treatments, which was mainly related to the accumulation of trans-9-18:1 in the cells. Adipocytes were able to desaturate a significant proportion of absorbed trans-11-18:1 and trans-13-18:1 (~20 and 30% respectively) to cis-9,trans-11-18:2 and cis-9,trans-13-18:2, whereas trans-9-18:1 was mostly incorporated intact resulting in a greater lipophilic index (i.e. decreased mean FA fluidity) of adipocytes. Trans-9-18:1 up-regulated (P < 0.05) the expression of lipogenic genes including acetyl-CoA carboxylase (1.65 fold), FA synthase (1.45 fold), FA elongase-5 (1.52 fold) and stearoyl-CoA desaturase-1 (1.49 fold), compared to the control, whereas trans-11-18:1 and trans-13-18:1 did not affect the expression of these genes compared to control. Our results suggest that the metabolism and lipogenic properties of trans-11-18:1 and trans-13-18:1, typically the most abundant trans FA in beef from cattle fed forage-based diets, are similar and are different from those of trans-9-18:1, the predominant trans FA in PHVO.

Isolation of α-linolenic acid biohydrogenation products by combined silver ion solid phase extraction and semi-preparative high performance liquid chromatography.

Polyunsaturated fatty acids typically found in cattle feed include linoleic (LA) and α-linolenic acid (ALA). In the rumen, microbes metabolize these resulting in the formation of biohydrogenation products (BHP), which can be incorporated into meat and milk. Bioactivities of LA-BHP, including conjugated linoleic acid (cis (c) 9,trans (t) 11-18:2 and t10,c12-18:2) and trans fatty acid isomers (t9-, t10- and t11-18:1) have been investigated, but effects of several BHP unique to ALA have not been extensively studied, and most ALA-BHP are not commercially available. The objective of the present research was to develop methods to purify and collect ALA-BHP using silver ion (Ag(+)) chromatography in sufficient quantities to allow for convenient bioactivity testing in cell culture. Fatty acid methyl esters (FAME) were prepared from perirenal adipose tissue from a cow enriched with ALA-BHP by feeding flaxseed. These were applied to Ag(+)-solid phase extraction, and eluted with hexane with increasing quantities of acetone (1, 2, 10, 20%) or acetonitrile (2%) to pre-fractionate FAME based on degree of unsaturation and double bond configuration. Fractions were collected, concentrated and applied to semi-preparative Ag(+)-high performance liquid chromatography (HPLC) for the isolation and collection of purified isomers, which was accomplished using isocratic elutions with hexane containing differing amounts of acetonitrile (from 0.015 to 0.075%). Purified trans-18:1 isomers collected ranged in purity from 88 to 99%. Purity of the ALA-BHP dienes collected, including c9,t13-18:2, t11,c15-18:2 and t10,c15-18:2, exceeded 90%, while purification of other dienes may require the use of other complementary procedures (e.g. reverse phase HPLC).

[[omega-(Heterocyclylamino)alkoxy]benzyl]-2,4-thiazolidinediones as potent antihyperglycemic agents.

A series of [(ureidoethoxy)benzyl]-2,4-thiazolidinediones and [[(heterocyclylamino)alkoxy]-benzyl]-2,4-thiazolidinediones was synthesized from the corresponding aldehydes. Compounds from the urea series, exemplified by 16, showed antihyperglycemic potency comparable with known agents of the type such as pioglitazone and troglitazone (CS-045). The benzoxazole 49, a cyclic analogue of 16, was a very potent enhancer of insulin sensitivity, and by modification of the aromatic heterocycle, an aminopyridine, 37, was identified as a lead compound from SAR studies. Evaluation of antihyperglycemic activity together with effects on blood hemoglobin content, to determine the therapeutic index, was performed in 8-day repeat administration studies in genetically obese C57 Bl/6 ob/ob mice. From these studies, BRL 49653 (37) has been selected, on the basis of antihyperglycemic potency combined with enhanced selectivity against reductions in blood hemoglobin content, for further evaluation.

Decompression illness in sports divers detected with technetium-99m-HMPAO SPECT and texture analysis.

UNLABELLED: Diving for sport and recreation has increased in recent years, resulting in more incidences of diving illness. Therefore, we studied potential use of regional cerebral blood flow SPECT imaging with 99mTc-HMPAO in the management of divers who have experienced decompression illness (DCI). METHODS: A group of ten sports divers who had no experience of DCI were compared with ten sports divers who had experienced at least one episode of DCI. Transaxial SPECT images were first compared objectively using a first-order texture measure and then subjectively using a receiver operator characteristic (ROC) experiment. Experienced observers were asked to rate images subjectively in terms of the images' textural appearance. RESULTS: Both these techniques showed that there is a statistically significant difference between the two groups and the images produced by the DCI divers were generally more coarsely patchy when compared to the non DCI divers. The quantitative texture technique proved significantly better in identifying divers with DCI than the visual analysis by observers using ROC curves. CONCLUSION: Differences between the cerebral blood flow patterns of sports divers who have experienced DCI and sports divers who have no experience of DCI can be detected using 99mTc-HMPAO SPECT and a texture analysis technique.

Localized amniotic fluid embolism presenting as ovarian vein thrombosis and refractory postoperative fever.

Amniotic fluid embolism is a rare, usually fatal obstetric emergency. This is a case of a documented puerperal embolization presenting as an isolated thrombosis of the right ovarian vein. Neither the classic cardiopulmonary decompensation nor the defibrinogenation syndrome developed in our subject. To our knowledge, this is the first reported case of an isolated amniotic fluid embolism precipitating ovarian vein thrombosis. Differentiation from septic pelvic thrombophlebitis without histologic examination of an excised surgical specimen is impossible. Whereas surgical intervention is usually not required in most cases of septic pelvic vein thrombophlebitis, ovarian vein resection and unilateral adnexectomy were necessary in our patient.

Diagnosis and management of face presentation.

Face presentation is an unusual complication of pregnancy; it occurs once in every 500 to 600 deliveries. Prematurity, fetal macrosomia, anencephaly, and cephalopelvic disproportion (CPD) are the major obstetric factors that predispose the fetus to face presentation. Although the mechanisms of labor in face presentation are different from those of simple vertex presentation, there is no consistent alteration in the duration of labor in the absence of underlying CPD. When disproportion does not exist and gross anomalies are not present, the prognosis for spontaneous vaginal delivery is excellent. The majority of perinatal losses reported in face presentation have resulted from traumatic operative vaginal deliveries, specifically version and extraction and midforceps rotations. Recent experience at this institution with a limited series of face presentations demonstrates that, with careful intrapartum surveillance, delivery can be accomplished with no increase in risk to either mother or fetus.

Mondor disease in pregnancy.

Mondor disease, or superficial thrombophlebitis of the breast, is an uncommon disorder that occurs only rarely in pregnant women. One such case is presented here followed by a review of the clinicopathologic features of the disease. Accurate diagnosis of Mondor disease is based almost entirely on careful physical examination of the breast, and no specific treatment is required. Its major clinical significance lies in the need to distinguish it from malignancy of the breast.

Pathophysiology and management of postcesarean endomyometritis.

Endomyometritis is the most common complication associated with cesarean delivery. The incidence varies from 5 to 85%, depending upon the patient population surveyed. The major risk factors for postcesarean endomyometritis are young age, low socioeconomic status, and extended duration of labor and ruptured membranes. The principal microorganisms responsible for infection are group B streptococci, aerobic gram-negative bacilli, anaerobic gram-positive cocci, and anaerobic gram-negative bacilli. The mean incidence of bacteremia in patients with endomyometritis is 10%. Less than 2% of infected patients develop life-threatening complications such as septic shock, pelvic abscess, or septic pelvic thrombophlebitis. Antibiotics of proved value in treatment of postcesarean endomyometritis include the newer broad-spectrum cephalosporins and ureidopenicillins and the combination regimen of clindamycin plus aminoglycoside.

An orientation program for new residents in obstetrics and gynecology.

OBJECTIVE: To describe a comprehensive orientation program for new medical school graduates beginning residency training in obstetrics and gynecology. METHODS: A three-phase orientation program was developed and administered over 5 days before the start of formal residency training. The first phase provided instruction in basic cardiac life support and neonatal resuscitation. In the second phase, a mini-core curriculum was presented through interactive small-group seminars. Seminar topics included prenatal care, fetal heart rate monitoring, labor and vaginal delivery, cesarean delivery, intrapartum and puerperal infection, antibiotic selection, ectopic pregnancy, and pelvic inflammatory disease. In the final phase of the program, the new graduates participated in five practical exercises designed to teach basic examination and surgical techniques. RESULTS: Two groups of five new graduates completed the orientation program. All rated the program as excellent and recommended that it be made a permanent part of the curriculum. The overall cost of the program was less than $300 per trainee. CONCLUSION: A comprehensive orientation program emphasizing acquisition of practical clinical and surgical skills was successful in facilitating the transition from medical school to residency training in obstetrics and gynecology.

Development of a guidebook for senior students applying for residency training in obstetrics and gynecology.

This article describes a detailed residency guidebook that I developed over the course of 4 years based on interaction with 42 student advisees. Questions most frequently asked by the students were recorded, and comprehensive written responses were prepared that addressed their specific concerns. The completed guidebook contains several major sections. The introductory portion provides a general description of the discipline of obstetrics and gynecology, outlines the format of residency training programs, and assesses the competitiveness of residencies in obstetrics and gynecology compared with other disciplines. The second section lists deadlines for completing various tasks, such as selecting an adviser, planning the senior curriculum, requesting and submitting applications, preparing the curriculum vitae and personal statement, and soliciting letters of recommendation. The next section of the guidebook provides suggestions for the senior curriculum and specifically addresses the issue of "audition electives" in obstetrics and gynecology. The next two sections present formats for the student's personal statement and curriculum vitae. Next, guidelines for requesting letters of recommendation are presented. Thereafter, information is provided to help students determine the number of applications they should submit, and training programs targeted by the student are classified by size, type, and competitiveness. Finally, the guidebook addresses questions related to scheduling and preparing for interviews.

Antibiotic prophylaxis for abdominal hysterectomy.

Ninety-one patients were enrolled in a prospective randomized double-blind study evaluating the efficacy of systemic antibiotic prophylaxis in reducing the incidence of operative site infection after abdominal hysterectomy. Forty-five patients received a 2-dose course of cefoxitin; 46 patients received a placebo. Although patients in the antibiotic group had a lower fever index, there were no statistically significant differences between groups with respect to incidence of pelvic cellulitis, urinary tract infection, wound infection, need for therapeutic antibiotics, or duration of hospitalization. It is concluded that, in this patient population, the theoretic risks of widespread use of systemic antibiotics for prophylaxis outweigh the observed benefits.

Statistics for the Residency Review Committee: a clear windows approach.

Because the reporting requirements imposed by the Residency Review Committee (RRC) for Obstetrics and Gynecology have become more extensive, we sought to develop a Microsoft Windows 3.1 (Microsoft Corp., Redmond, WA)-based computer program for maintaining an on-line record of resident surgical experience. Data input for our program occurs in two stages. All residents are responsible for maintaining separate obstetrics and gynecology-primary care statistical booklets. Each booklet consists of individual perforated data sheets. The front of the obstetrics data sheets is a replica of the bottom portion of RRC S Form Obstetrics. The reverse side is a replica of the top half of S Form Obstetrics, listing all "accountable" obstetric procedures, coded by level of operator responsibility. The front of the gynecology data sheet replicates the S Form Primary and Preventive Ambulatory Medicine. The reverse of this sheet is a replica of S Form Gynecology and lists all "accountable" gynecologic procedures, again coded by level of operator responsibility. Residents submit data sheets on a daily basis to the residency program coordinator, who then enters each patient encounter into a user-friendly data base program. Data entry screens are essentially identical to the individual encounter forms, and input requires fewer than 30 seconds per form. Once the individual patient's data is entered on the screen, the computer program automatically updates the resident's cumulative surgical experience and stratifies experience by year of training. At any time, program administrators have on-line access to a comprehensive record of an individual resident's or group of residents' clinical experience.

Hepatitis A vaccine: ready for prime time.

Two new inactivated hepatitis A vaccines are available that confer long-term protection against infection. They are indicated for pre-exposure prophylaxis in persons older than 2 years of age. For one vaccine preparation, Vaqta (Merck and Co., West Point, PA), the recommended schedule for adults is a 1.0-mL (50 U of hepatitis A viral antigen) intramuscular dose initially, followed by a booster dose 6-12 months later. Children 2-17 years of age should receive 0.5 mL (25 U of hepatitis A viral antigen) initially, followed by a booster dose 6-18 months later. The adult dosage schedule for Havrix (SmithKline Beecham, Philadelphia, PA) is a 1.0-mL (1440 enzyme-linked immunosorbent assay [ELISA] units) intramuscular dose initially, followed by a 1.0-mL booster dose 6-12 months later. Patients 2-18 years of age should receive doses of 0.5 mL (720 ELISA units). Primary candidates for vaccination are travelers to regions of endemic disease, children living in high-prevalence areas, homosexual males, users of illicit intravenous drugs, persons working directly with nonhuman primates or hepatitis A virus, patients older than 30 years of age with chronic liver disease, and persons who have received a liver transplant or are awaiting one. Seroconversion rates in healthy children and adults exceed 95%. Both vaccines are safe for use in pregnancy. The cost of the vaccine for adult patients is approximately $50 to $60.

Antibiotic prophylaxis for cesarean delivery: is an extended-spectrum agent necessary?

The purpose of this investigation was to determine whether an extended-spectrum antibiotic with a long duration of action was more effective for prophylaxis for cesarean delivery than a limited-spectrum agent with a shorter duration of action. Patients were eligible for the study if they were in labor or had ruptured membranes at the time of surgery. In a randomized, double-blind manner, 377 women were assigned to receive 2 g of cefazolin (192) or 2 g of cefotetan (185) intravenously immediately after the infant's umbilical cord was clamped. There were no significant differences between groups with respect to the frequency of febrile morbidity (22.4 versus 21.6%), the mean fever index (15.8 versus 14.9 degree-hours), the frequency of endometritis (19.3 versus 21.1%), or the mean duration of postoperative hospitalization (3.8 versus 3.9 days). Among patients who became infected despite prophylaxis, enterococcus was isolated with disproportionate frequency. This organism was responsible for 89% of the postoperative urinary tract infections and all three cases of bacteremia. It was also the second most common isolate in women with endometritis. A single dose of cefazolin is comparable in effectiveness to cefotetan. In view of the cost difference between the two antibiotics, there is no justification for use of the more expensive, extended-spectrum agent.