Neural dysregulation during a working memory task in human immunodeficiency virus-seropositive and hepatitis C coinfected individuals.

Cognitive and functional neural correlates of human immunodeficiency virus (HIV) are only partially understood at present. Variability in neural response, which has been noted in the literature, may relate to clinical factors associated with HIV, including time since HIV diagnosis, CD4 count and nadir, HIV viral load, and comorbid infectious processes, especially hepatitis C. The present investigation evaluated working memory-related functional neural activation in 26 HIV+ participants, 28 demographically matched HIV-seronegative individuals, and 8 HIV+ individuals with hepatitis C coinfection. Analyses examined impact of HIV infection duration, CD4 count and nadir, HIV viral load, and hepatitis C serostatus. Results showed that HIV-seronegative participants had fastest reaction times, and during the working memory task, HIV+ participants with hepatitis C coinfection showed strongest bias toward commission errors; however, signal detection (i.e., overall task performance) was equivalent across groups. Functional magnetic resonance imaging (fMRI) results showed HIV-related greater activation to an easier vigilance task and HIV-related lower activation to a more difficult working memory task, consistent with reduced cognitive reserve. Hepatitis C coinfection related to diffuse neural dysregulation. Correlational analyses suggested relationships of increasingly severe disease with poorer functioning in brain regions linked to error monitoring and attention regulation.

Technology Complements Physical Examination and Facilitates Skills Development among Health Sciences Clerkship Students: An Integrative Literature Review.

Background: Technology is increasingly present in the clinical environment. There is a dearth of investigation of the relationship between technology and touch concerning student learning of physical examination practices. Method: Integrative review methods were used to synthesise empirical literature to provide a comprehensive understanding of the relationship between physical examination, learning and technology in the context of health professional student clerkships. Results: Three databases including MEDLINE, CINAHL and Eric were searched for all articles published from 2014 to 2021 using terms relating to (i) physical examination, (ii) technology, and (iii) student clerkships. Thirty-three studies met the inclusion criteria. From the analysis, it is evident that technologies that intersect with learning of physical examination may broadly be apportioned into two categories: 1) technologies that mediate physical examination practices; and 2) technologies that mediate the learning of physical examination. Conclusions: This review indicates that technologies may have multiple roles in the student learning of physical examination, including technology mediating increased diagnostic accuracy and access to supplementary learning material relating to physical examination that is integrated for the clinical clerkship environment. It highlights a need to further understand the touch versus technology relationship and explore the dynamic intersection.

Acute Respiratory Infection Incidence and Outpatient Antibiotic Prescription Patterns in People With or Without Human Immunodeficiency Virus Infection: A Virtual Cohort Study.

Background: Inappropriate antibiotic use in acute respiratory infections (ARIs) is a major public health concern; however, data for people with human immunodeficiency virus (PWH) are limited. Methods: The HIV Virtual Cohort Study is a retrospective cohort of adult Department of Defense beneficiaries. Male PWH cases (n = 2413) were matched 1:2 to controls without HIV (n = 4826) by age, gender, race/ethnicity, and beneficiary status. Acute respiratory infection encounters between 2016 and 2020 and corresponding antibiotic prescriptions were characterized as always, sometimes, or never appropriate based on International Classification of Diseases, Tenth Revision coding. Incidence of ARI encounters and antibiotic appropriateness were compared between PWH and controls. Subgroup analyses were assessed by CD4 count and viral load suppression on antiretroviral therapy. Results: Mean rates of ARI encounters were similar for PWH (1066 per 1000 person-years) and controls (1010 per 1000 person-years); however, the rate was double among PWH without viral load (VL) suppression (2018 per 1000 person-years). Antibiotics were prescribed in 26% of encounters among PWH compared to 34% for controls (P ≤ .01); antibiotic use was "never" appropriate in 38% of encounters with PWH and 36% in controls. Compared to controls, PWH received more sulfonamides (5.5% vs 2.7%; P = .001), and variation existed among HIV subgroups in the prescription of sulfonamides, fluoroquinolones, and ß-lactams. Discussion: Acute respiratory infection encounters were similar for PWH and those without HIV; however, PWH with lower CD4 counts and/or nonsuppressed VL had more frequent ARI visits. Inappropriate antibiotic use for ARIs was high in both populations, and focused interventions to improve antibiotic appropriateness for prescribers caring for PWH should be pursued.

Are medical students influenced by preceptors in making career choices, and if so how? A systematic review.

INTRODUCTION: Increasingly medical students undertake clinical training in distributed learning environments. The driving factor for this is predominantly to address medical workforce shortages. In these environments students are often taught by private practitioners, residents, house staff and registrars, as well as faculty. Through a mix of short- and long-term preceptorships, clerkships and rotations, medical students are exposed to a wider range of preceptors, mentors and role models than has traditionally been the case. The aim of this systematic review was to understand if and how medical students' career choices are influenced by their interactions with preceptors. METHOD: A search of Ovid Medline, Scopus, ISI Web of Science, PubMed, Eric and CIHNAL was undertaken. The search was structured around the key terms: Medical Student, Career Choice and Preceptor, and variants of these terms. Search limits were set to English-language publications between 1995 and 2010. RESULTS: A total of 36 articles met the selection criteria from the 533 citations sourced from the search. Required preceptorships as short as 3 weeks' duration influence the career choice of students when they rate the preceptor as a high quality teacher. Preceptors who are judged (by students) as high quality teachers have the greatest influence on student career choice by up to four-fold. When students judged a preceptor as being a negative role model, a poor teacher or lacking discipline specific knowledge they will turn away from that field. The positive influence of relationships between preceptors and students on career choice is strongest where there is continuity of preceptors, continuity of care, and continuity of patient interactions. The longer the duration of the preceptorship the greater the influence on student career choice, particularly in primary cares environments. CONCLUSION: This review adds to the literature by identifying how differing components and combinations of components of a preceptorship influence medical student career choices. Multiple components of the preceptorship combined have a greater influence. In free choice, longitudinal integrated clerkships' duration of placement and continuity relationships with preceptors have the greatest influence on medical students in pursuing a primary care career. This information informs medical schools, curriculum designers and policy-makers in reforming medical education to address workforce shortages.

Development of a tool to measure holistic reflection in midwifery students and midwives.

BACKGROUND: Holistic reflection encompasses reflection as a continuum, incorporating critical reflection, reflexivity, critical thinking and a whole-of-person approach. The development of holistic reflection in midwifery students and midwives is rarely measured in a standardised way. AIM: To develop and test a tool to measure holistic reflection in midwifery students and midwives, for use in pre-registration and post-graduate education, and research. DESIGN: The eight-step approach to tool development by DeVellis was followed with psychometric testing of data from a cross-sectional survey. PARTICIPANTS: Midwifery students (pre-registration and postgraduate), and midwifery alumni of an Australian university. METHODS: Draft items (n = 84) were generated from review of the literature, qualitative research, and a theoretical model. An expert panel (n = 19) reviewed draft items resulting in 39 items. The survey included demographic details, the draft Holistic Reflection Assessment Tool, emotional intelligence subscale, and a social desirability scale. Participants repeated the online survey at two weeks to confirm test-retest reliability. RESULTS: The 187 responses were received. Exploratory factor analysis with varimax rotation revealed three factors accounting for 49% of variance. Internal consistency of the tool was high (α = .91) and test-retest reliability at two weeks (α = .93) demonstrated stability. There were low correlations between social desirability (r = .22, p < .001) and emotional intelligence (r = .21, p < .001) with the new holistic reflection scale. CONCLUSIONS: The Holistic Reflection Assessment Tool is the first for midwifery. The tool was reliable, stable, and valid. Further research is warranted for criterion validity.

Geographical variations in the prevalence of atopic sensitization in six study sites across Canada.

BACKGROUND: Geographical variations in atopic sensitization in Canada have not been described previously. This study used the standardized protocol of the European Community Respiratory Health Survey-1 (ECRHS-1) to investigate the distribution and predictors of atopic sensitization in six sites across Canada and to compare the results with some ECRHS-1 centers. METHODS: Adults aged 20-44 years in six study sites across Canada underwent allergy skin testing using 14 allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) cat, cockroach, grasses (Timothy grass, Kentucky grass), molds (Cladosporium herbarium, Alternaria alternata, Aspergillus fumigatus, Penicillium), trees (tree mix, birch, Olea europea), and common ragweed. RESULTS: The overall prevalence of atopy (skin test over 0 mm to any allergen) was 62.7%. There was significant geographical variation in the prevalence of atopy in the six study sites (lowest 55.6% [95% C.I.51.3-59.9] in Prince Edward Island, highest 66.0 [61.7-70.3] in Montreal) and of sensitization to each of the allergens tested even after adjustment for confounders. When the first eight of the nine allergens in the ECRHS were used to estimate the prevalence of atopic sensitization, the prevalence of atopy in Canada was 57% compared with 35.2% overall for centers in the ECRHS. The prevalence of atopy in Vancouver (57% [52.3-61.8]) was close to that of Portland, Oregon (52.1% [46.2-58.0]). CONCLUSION: There was a significant variation in atopic sensitization among different study sites across Canada. The prevalence of atopic sensitization is relatively high in Canada compared with sites in the ECRHS and this may, in part, account for the high prevalence of asthma and asthma symptoms in Canada.

Two distinct enzymes contribute to biphasic S6 phosphorylation in serum-stimulated chicken embryo fibroblasts.

Serum stimulation of quiescent chicken embryo fibroblasts resulted in a time-dependent, biphasic activation of S6 kinase activity. Chromatographic fractionation of serum-stimulated cell lysates resolved two distinct S6 kinase activities. Anti-Xenopus S6 kinase II antiserum immunoprecipitated a 90,000-Mr S6 kinase but did not cross-react with a smaller, 65,000-Mr S6 kinase. Phosphopeptide analysis confirmed that the 90,000- and 65,000-Mr proteins were structurally unrelated and established that the 65,000-Mr protein isolated by the current protocol was the same serum-stimulated chicken embryo fibroblast S6 kinase as that previously characterized (J. Blenis, C. J. Kuo, and R. L. Erikson, J. Biol. Chem. 262:14373-14376, 1987). These results demonstrate the contribution of two distinct S6 kinases to total serum-stimulated ribosomal protein S6 phosphorylation.

Sequence and expression of chicken and mouse rsk: homologs of Xenopus laevis ribosomal S6 kinase.

We have previously reported the isolation of cDNAs encoding two closely related Xenopus ribosomal S6 kinases, S6KII alpha and -beta (S. W. Jones, E. Erikson, J. Blenis, J. L. Maller, and R. L. Erikson, Proc. Natl. Acad. Sci. USA 85:3377-3381, 1988). We report here the molecular cloning of one chicken and two mouse homologs of the Xenopus laevis cDNAs. As described for the Xenopus proteins, these cDNAs were found to predict polypeptides that contain two distinct kinase domains, of which one is most closely related to the catalytic subunit of cyclic AMP-dependent protein kinase and the other is most closely related to the catalytic subunit of phosphorylase b kinase. The three predicted proteins were more than 79% identical to the Xenopus S6KII alpha protein. The chicken and one of the mouse cDNAs were, respectively, 3.7 and 3.1 kilobase pairs in length, predicted proteins of 752 and 724 amino acids with molecular weights of 84.4 and 81.6 kilodaltons, and hybridized to mRNAs in fibroblasts and tissues of approximately 3.6 and 3.4 kilobases (kb). The second mouse cDNA was approximately 6.1 kilobase pairs and was not full length but predicted the C-terminal 633 amino acids of a protein that is similar to the C-terminal portion of Xenopus S6KII alpha. This clone hybridized to mRNA transcripts of 7.6 and 3.4 kb. In vitro transcription and translation of the chicken and the mouse cDNAs that predict complete proteins produced major products with apparent molecular weights of 96 and 84 kilodaltons. Analysis of mRNA levels in chicken tissues showed significant quantities of the 3.6-kb transcript in small and large intestine, spleen, and bursa. Both mouse cDNA were similarly expressed at significant levels in intestine, thymus, and lung; however, the 7.6-kb mRNA was differentially and more highly expressed in heart and brain. The two mouse cDNAs represent two different S6 kinase genes, as shown by comparison of their protein sequences, mRNA transcript sizes, genomic organizations, and nucleic acid sequences. We propose that this family of genes be named rsk, for ribosomal S6 kinase.

Identification of mitogen-responsive ribosomal protein S6 kinase pp90rsk, a homolog of Xenopus S6 kinase II, in chicken embryo fibroblasts.

Antiserum raised against recombinant Xenopus ribosomal protein S6 kinase (rsk) was used to identify a 90,000-Mr ribosomal S6 kinase, pp90rsk, in chicken embryo fibroblasts. Adding serum to cells stimulated the phosphorylation of pp90rsk on serine and threonine residues and increased the activity of S6 kinase measured in immune complex assays. Xenopus S6 kinase II and chicken embryo fibroblast pp90rsk had nearly identical phosphopeptide maps.

3D-printed poly(vinylidene fluoride)/carbon nanotube composites as a tunable, low-cost chemical vapour sensing platform.

We report the production of flexible, highly-conductive poly(vinylidene fluoride) (PVDF) and multi-walled carbon nanotube (MWCNT) composites as filament feedstock for 3D printing. This account further describes, for the first time, fused deposition modelling (FDM) derived 3D-printed objects with chemiresistive properties in response to volatile organic compounds. The typically prohibitive thermal expansion and die swell characteristics of PVDF were minimized by the presence of MWCNTs in the composites enabling straightforward processing and printing. The nanotubes form a dispersed network as characterized by helium ion microscopy, contributing to excellent conductivity (∼3 × 10-2 S cm-1). The printed composites contain little residual metal particulate relative to parts from commercial PLA-nanocomposite material visualized by micro-X-ray computed tomography (µ-CT) and corroborated with thermogravimetric analysis. Printed sensing strips, with MWCNT loadings up to 15% mass, function as reversible vapour sensors with the strongest responses arising with organic compounds capable of readily intercalating and subsequently swelling the PVDF matrix (acetone and ethyl acetate). A direct correlation between MWCNT concentration and resistance change was also observed, with larger responses (up to 161% after 3 minutes) being generated with decreased MWCNT loadings. These findings highlight the utility of FDM printing in generating low-cost sensors that respond strongly and reproducibly to target vapours. Furthermore, the sensors can be easily printed in different geometries, expanding their utility to wearable form factors. The proposed formulation strategy may be tailored to sense diverse sets of vapour classes through structural modification of the polymer backbone and/or functionalization of the nanotubes within the composite.

Partial sleep deprivation impacts impulsive action but not impulsive decision-making.

Sleep deprivation may lead to increased impulsivity, however, previous literature has focused on examining effects of total sleep deprivation (TSD) rather than the more common condition, partial sleep deprivation (PSD) or 'short sleep'. Moreover, it has been unclear whether PSD impacts impulse-related cognitive processes, and specifically if it differentially affects impulsive action versus impulsive decision-making. We sought to determine if short compared to long sleep (6 vs. 9h/night) impacts impulsive action via behavioral inhibition (Go/No-Go), and/or impulsive decision-making processes of risk taking (Balloon Analogue Risk Task [BART]) and preferences for immediate over delayed rewards (Delay Discounting). In a within-subject design, 34 participants (71% female, mean age=37.0years, SD=10.54) were assigned to four consecutive nights of 6h/night (short sleep) and 9h/night (long sleep) in their own home in random counterbalanced order. Sleep was measured via wrist-worn actigraphs to confirm adherence to the sleep schedules (mean short sleep=5.9h, SD=0.3; mean long sleep=8.6h, SD=0.3, p<0.001). The Go/No-Go, BART, and Delay Discounting tasks were completed following both sleep conditions. Participants had more inhibition errors on the Go/No-Go task after short (mean false alarms=19.79%, SD=14.51) versus long sleep (mean=15.97%, SD=9.51, p=0.039). This effect was strongest in participants reporting longer habitual time in bed (p=0.04). There were no differences in performance following long- versus short-sleep for either delay discounting or the BART (p's>0.4). Overall, these results indicate that four days of PSD diminishes behavioral inhibition abilities, but may not alter impulsive decision-making. These findings contribute to the emerging understanding of how partial sleep deprivation, currently an epidemic, impacts cognitive ability. Future research should continue to explore the connection between PSD and cognitive functions, and ways to minimize the occurrence and negative consequences of short sleep.

Transgenic mice deficient in the LAR protein-tyrosine phosphatase exhibit profound defects in glucose homeostasis.

Protein-tyrosine phosphatases (PTPases) play an integral role in the regulation of cellular insulin action. LAR, a transmembrane PTPase expressed in insulin-sensitive tissues, acts as a negative regulator of insulin signaling in intact cell models. The physiological role of LAR was studied in mice in which LAR expression was eradicated by insertional mutagenesis. In the fasting state, adult male homozygous LAR (-/-) mice had significantly lower plasma levels of insulin and glucose, as well as a reduced rate of hepatic glucose production compared with wild-type controls, suggesting a heightened level of insulin sensitivity. In euglycemic clamp studies, the LAR (-/-) mice exhibited a significant resistance to insulin-stimulated glucose disposal and suppression of hepatic glucose output. Examination of hepatic insulin action demonstrated that the major alteration involved a 47% reduction in insulin-stimulated phosphatidylinositol 3'-kinase (PI 3-kinase) activity in the knockout mice, indicating a post-receptor signaling defect. Taken together with previous work on the cellular effects of LAR, the present results are consistent with a physiological role for LAR in the negative regulation of insulin action, with secondary abnormalities that contribute to the resistance to insulin-stimulated signaling in the knockout mice. Overall, these data provide further evidence for an important role for LAR in the regulation of insulin action and glucose homeostasis in intact animals.

Transfer of functional insulin receptors to receptor-deficient target cells.

Purified human insulin receptors incorporated into phospholipid vesicles have previously been shown to retain insulin binding as well as insulin-stimulated beta-subunit autophosphorylating activity. These vesicles were used as a vehicle to transfer receptors to the insulin receptor-deficient Madin-Darby canine kidney (MDCK) cell line. Fusion of control [14C] dioleoylphosphatidylcholine-labeled phospholipid vesicles with MDCK cells was found to be dependent on both the amount of time and the concentration of polyethylene glycol used for fusion. Optimal insulin receptor transfer, as determined by recovery of [125I]insulin binding, occurred when MDCK cells were incubated for 45 min at 37 C in the presence of 15% polyethylene glycol plus receptor-containing vesicles. Scatchard analyses for insulin receptor binding before and after vesicle fusion demonstrated no postfusion alteration in insulin receptor affinity and a 10-fold increase in the number of insulin receptors present in the MDCK cells. Fusion transfer of insulin receptors to MDCK cells rendered the cells sensitive to insulin (10-100 nM) for stimulation of glycogen synthesis. Chloroquine (0.1 mM) was found to block endosomal processing of receptor-bound [125I] insulin within 1 h. These findings indicate that insulin receptors function as dissociable units which can be inserted into target plasma membranes with resultant recoupling to cellular systems.

The membrane-associated 40 KD fatty acid binding protein (Berk's protein), a putative fatty acid transporter is present in human skeletal muscle.

Muscle tissue (1.1 +/- 0.1 grams) was obtained from seven healthy individuals (3 males, 4 females) using an open incision approach before and after ingestion of either 75 grams of dextrose (N=5) or water (N=2). Purified sarcolemmal membranes from the muscle were prepared using a sucrose step gradient. A polyclonal antibody raised against the purified (99%) rat hepatocyte 40 KD membrane fatty acid binding protein (mFABP-L) was used to probe for this putative transporter in the muscle membranes using Western blot. A single band at the 40 KD MW band was identified which reacted antigenically with the protein purified from rat livers. These response of Berk's protein 60-75 minutes after dextrose ingestion (or water) was erratic and no specific trend could be identified. Our data demonstrate that the 40 KD mFABP-L originally isolated from rat liver is also present in human skeletal muscle membrane. This protein may be involved in transport of fatty acids across the membrane of skeletal muscle, however its physiological role in human fatty acid metabolism remains to be established.

Emotional and personality changes following cingulotomy.

The effects of bilateral anterior cingulate cortex (ACC) lesions on emotional and personality functioning were studied. Patients undergoing cingulotomy for chronic intractable pain were assessed on the Minnesota Multiphasic Personality Inventory (MMPI), the Profile of Mood States (POMS), cognitive tests, and pain ratings, pre- and postsurgically. Patients with intractable pain, not treated with cingulotomy, served as controls. Cingulotomy patients experienced reductions in POMS-Tension, POMS-Anger, and MMPI Scale 7 (Psychasthenia) compared with baseline and the controls. POMS-Tension was significantly correlated with attention-intention performance. The results indicate that the ACC modulates emotional experience, related to self-perceived tension, and that there is relationship between the emotional and the attentional effects of cingulotomy.

Dissociation of affect recognition and mood state from blunting in patients with schizophrenia.

The present study was designed to investigate the relationships between expression, perception, and experience of emotion in schizophrenic patients with and without affective blunting. Cognitive processing speed, emotional perception, and emotional experience were assessed in 25 schizophrenic patients grouped according to scores on a measure of overt emotional expression (Rating Scale for Emotional Blunting). Results showed dissociation of emotional expression from emotional perception and emotional experience. Blunted schizophrenic patients were no more impaired in the perception of emotion (Profile of Nonverbal Sensitivity) than non-blunted schizophrenic patients. In addition, groups did not differ in intensity of emotional experience as quantified on the self-report of arousal state (Positive and Negative Affect Scales). Accuracy of perception and reported experience of emotion did not differ between groups as a function of emotional valence. Cognitive processing speed (Symbol Digit Modalities Test; SDMT) was related to blunting score and to perception accuracy, although the SDMT did not differ between groups. Results are discussed in terms of a neuropathological basis for impairment of emotional expression.

Decreased DNA repair in familial Alzheimer's disease.

Alterations in the capacity of a cell to repair DNA lesions play an important role in a number of human diseases. We and others have demonstrated defective DNA repair of alkylation damage in cells from patients with Alzheimer's disease. It has been hypothesized that this defect is related to the cause of Alzheimer's disease and results in the accumulation of lesions in the central nervous system neurons. One prediction of this hypothesis is that in dominantly inherited Alzheimer's disease, the repair defect will be present in half of the offspring of affected patients long before they develop symptoms of the disease. In order to test the hypothesis that decreased DNA repair is responsible for familial Alzheimer's disease and their at-risk offspring we have studied DNA repair in these individuals after exposure of lymphoblasts to alkylating agents. Our results indicate that cell lines from affected patients repair significantly less damage in 3 h than cell lines from healthy controls. A small number of at-risk individuals were also studied and some of these had lower levels of repair, although more cell lines from individuals in this group must be studied. These findings provide further support for defective DNA repair playing a role in the pathogenesis of Alzheimer's disease.

Acute and chronic life cycle toxicity of acenaphthene and 2,4,6-trichlorophenol to the midge Paratanytarsus parthenogeneticus (Diptera: Chironomidae).

The acute and life cycle toxicities of acenaphthene and 2,4,6-trichlorophenol (2,4,6-TCP) were evaluated using the parthenogenic dipteran larva, Paratanytarsus parthenogeneticus, of the family Chironomidae. Static 48 h acute toxicity tests employed third instar larvae, and the flow-through 20-day life cycle tests were initiated with eggs. No acute lethal effect was observed in the saturated concentration (2.1 mg/l) of acenaphthene in water, and the median lethal concentration of 2,4,6-TCP was approximately 40 mg/l. In the life cycle toxicity test with acenaphthene, hatchability of the midge was affected by 50% at an exposure concentration of approximately 0.17 mg/l. The median effective concentration for larval, pupal and adult development was found between 0.06 and 0.07 mg/l, respectively, and these were significantly lower than the effective concentration for hatching success. With regard to 2,4,6-TCP toxicity, the median effective concentration for midge hatchability was 4.23 mg/l. The larval development, pupal formation and adult emergence, however were impeded at 1.60, 1.46 and 1.33 mg/l, respectively. Each level was noticeably lower than the median effective concentration for hatchability. The concentrations for each compound that interfered with the development to fourth instar, pupa and adult were not significantly different. These results indicate that larval developments after hatching were the most sensitive stages and affected the success of midge growth.

Hepatitis C in Prince Edward Island: a descriptive review of reported cases, 1990-1995.

INTRODUCTION: The prevalence of hepatitis C in Canada is not known. There is limited information on most small area populations such as Prince Edward Island. METHODS: A retrospective approach was used to obtain detailed information on all cases of hepatitis C identified in Prince Edward Island from December 1990 to September 1995. Cases were reviewed for demographic, clinical and risk factor information, including blood donation and transfusion histories. RESULTS: There were 54 RIBA confirmed cases of hepatitis C infection included in the Prince Edward Island Hepatitis C Database, of which 38 (70%) were males. Age ranged from 18 to 76 years, with a mean age of 38 years. Twenty-eight (52%) of the cases had a history of injection drug use, and 24 (44%) had received blood or blood products in the past. There were five cases with neither of these risk factors identified. DISCUSSION: The results suggest that, in this small, primarily rural population, injection drug use is the most common means of hepatitis C transmission, followed by receipt of blood or blood products.

Hepatitis B prenatal screening survey, Nova Scotia, 1990-1991.

We conducted a study in which 5,754 pregnant women who delivered at the Grace Maternity Hospital in Halifax were screened for HBsAg. There were five who were found to be seropositive for the first time (a screening yield for seropositivity of 8.7/10,000). Overall six were seropositive for a prevalence rate of 10.4/10,000. These rates are above the 6.0/10,000 level at which routine prenatal screening is considered to be cost-effective. Screening based upon risk factors would have identified only two of the five women who were found for the first time to be HBsAg seropositive. Based upon the results of this study, we recommend that routine screening for HBsAg be performed on all prenatal women in Nova Scotia.