Vaginal ring acceptability: A systematic review and meta-analysis of vaginal ring experiences from around the world

OBJECTIVE

The vaginal ring (ring) is a female-initiated, long-acting drug delivery system for different indications, including HIV prevention. Our aim was to provide evidence for acceptability of the vaginal ring across indications to support dapivirine and multipurpose prevention technology ring introduction and roll out.

STUDY DESIGN

This systematic review and meta-analysis followed PRISMA guidelines. We searched PubMed, Web of Science, Embase, and grey literature for publications reporting favorable ring acceptability and secondary outcomes involving actual ring use (comfort, ease of ring use, ring comfort during sex, expulsions, and vaginal symptoms) or hypothetical acceptability for any indication published January 1, 1970-June 15, 2021. We estimated random-effects pooled prevalence, assessing between-study variation using meta-regression.

RESULTS

Of 2,234 records, we included 123 studies with 40,434 actual and hypothetical ring users. The primary outcome assessment included 50 studies with 60 ring subgroups totaling 19,271 ring users. The favorable acceptability pooled prevalence was 85.6% (95%CI 81.3, 89.0), while hypothetical acceptability among non-ring users was 27.6% (95%CI 17.5, 40.5). In meta-regression, acceptability was higher in menopause (95.4%; 95%CI 88.4, 98.2) compared to contraceptive rings (83.7%; 95%CI 75.6, 89.5). Acceptability was lower in pharmacokinetic studies (50%; 95%CI 22.1, 77.9) compared to RCTs (89.5%; 95%CI 85.8.92.4) and in studies assessing acceptability at ≥12 months (78.5%; 95%CI 66.5, 87.1) versus studies assessing acceptability at <3 months (91.9%; 95%CI 83.7, 96.1). European (90.6%; 95%CI 83.9, 94.7), Asian (97.1%; 95%CI 92.0, 99.0), and multi-region studies (93.5%; 95%CI 84.6, 97.4) reported more favorable acceptability compared to African studies (59.4%; 95%CI 38.3, 77.5). Secondary outcomes were similarly favorable, including ring comfort (92.9%; 95%CI 89.2, 95.4), ease of use (90.9%; 95%CI 86.5, 94.0), and comfort during sex (82.7%; 95%CI 76.4, 87.6). Limitations include inconsistent outcome definitions and unmeasured factors affecting acceptability.

CONCLUSIONS

Women who used vaginal rings reported they were acceptable across indications geographic regions and indications. Policy makers should consider the ring as an important option for pregnancy and HIV prevention drug development.

IMPLICATIONS

This review found favorable acceptability among vaginal ring users across indications and geographic areas, in contrast to low hypothetical acceptability among non-users. Vaginal rings are an important drug delivery system for pregnancy and HIV preventions, and scale-up should plan to address initial hesitancy among new users.

389. Demographic and Clinical Characteristics of Suspect SARS-CoV-2 Reinfection Cases in Los Angeles County from March 10 to June 1, 2021: A Cross-sectional Study of Case Interview Data

Background

Probable and suspect SARS-CoV-2 reinfection has been reported globally, with implications for risk assessment and pandemic control. Genomic sequencing and supporting data are frequently unavailable to confirm SARS-CoV-2 reinfection.

Methods

In March 2021, Los Angeles County Department of Public Health began interviewing suspect reinfection cases, defined as individuals with SARS-CoV-2 RNA detected ≥ 90 days after the first detection of SARS-CoV-2 RNA via molecular testing. We conducted a cross-sectional study of case interview data from March 10 to June 1, 2021 to estimate the prevalence of suspect reinfection cases; describe the interval between repeat positives ≥ 90 days; and, estimate bivariate prevalence odds ratios (OR) with 95% confidence intervals (95% CI) for suspect reinfections and age, sex, race/ethnicity, reason for testing, symptomology, and comorbidities.

Results

From March 10 to June 1, 2021, we attempted 29,983 case interviews, including 1,901 (6.3%) suspect reinfection cases and 28,082 (93.7%) initial cases. Among suspect reinfection cases, the median interval between repeat positive tests was 117 days (interquartile range: 102, 141). Suspect reinfection cases had decreased odds of completing case interviews (n=738; 38.8%) compared to initial cases (n=13,263; 47.2%) (OR: 0.71; 95% CI: 0.65, 0.78). Among completed case interviews, suspect reinfection cases had increased odds of being older (50-64 years OR: 1.63 [95% CI: 1.32, 2.01]; ≥ 65 years OR: 3.77 [95% CI: 3.00, 4.74]; ref. 30-49 years); Hispanic/Latino (OR: 2.64 [95% CI: 2.10, 3.33]; ref. White); female (OR: 1.21 [95% CI: 1.04, 1.41]); reporting screening as their testing reason (OR: 10.39; [95% CI: 7.45, 14.48]; ref. known exposure); and reporting underlying health conditions (OR: 2.64; 95%CI: 2.24, 3.10). Suspect reinfection cases had decreased odds of being symptomatic (OR 0.15; 95% CI: 0.13, 0.18).

Conclusion

This analysis of case interview data indicates individuals who are older, Hispanic, female, and have underlying health conditions may be vulnerable populations for suspect reinfection. Limitations include unconfirmed reinfection and alternative explanations such as persistent positivity with decreased symptoms and infectivity over time.

Disclosures

All Authors: No reported disclosures

Vaginal ring acceptability and related preferences among women in low- and middle-income countries: A systematic review and narrative synthesis

The vaginal ring (VR) is a female-initiated drug-delivery platform used for different indications, including HIV pre-exposure prophylaxis (PrEP). We conducted a systematic review of VR acceptability, values and preferences among women in low- and middle-income countries (LMIC) to inform further investment and/or guidance on VR use for HIV prevention. Following PRISMA guidelines, we used structured methods to search, screen, and extract data from randomized controlled trials (RCTs) and observational studies reporting quantitative outcomes of acceptability of the VR for any indication published 1/1970-2/2019 (PROSPERO: CRD42019122220). Of 1,110 records identified, 68 met inclusion criteria. Studies included women 15-50+ years from 25 LMIC for indications including HIV prevention, contraception, abnormal bleeding, and menopause. Overall VR acceptability was high (71-98% across RCTs; 62-100% across observational studies), with 80-100% continuation rates in RCTs and favorable ease of insertion (greater than 85%) and removal 89-99%). Users reported concerns about the VR getting lost in the body (8-43%), although actual expulsions and adverse events were generally infrequent. Most women disclosed use to partners, with some worrying about partner anger/violence. The VR was not felt during intercourse by 70-92% of users and 48-97% of partners. Acceptability improved over time both within studies (as women gained VR experience and worries diminished), and over chronological time (as the device was popularized). Women expressed preferences for accessible, long-acting, partner-approved methods that prevent both HIV and pregnancy, can be used without partner knowledge, and have no impact on sex and few side effects. This review was limited by a lack of standardization of acceptability measures and study heterogeneity. This systematic review suggests that most LMIC women users have a positive view of the VR that increases with familiarity of use; and, that many would consider the VR an acceptable future delivery device for HIV prevention or other indications.

A Retrospective Cohort Study of Safety Outcomes in New Zealand Infants Exposed to Tdap Vaccine in Utero

We aimed to evaluate the safety of maternal Tdap; thus, we assessed health events by examining the difference in birth and hospital-related outcomes of infants with and without fetal exposure to Tdap. This was a retrospective cohort study using linked administrative datasets. The study population were all live-born infants in New Zealand (NZ) weighing at least 400 g at delivery and born to women who were eligible for the government funded, national-level vaccination program in 2013. Infants were followed from birth up to one year of age. There were a total of 69,389 eligible infants in the cohort. Of these, 8299 infants were born to 8178 mothers exposed to Tdap (12%), primarily between 28 and 38 weeks gestation as per the national schedule. Among the outcomes, we found a reduced risk for moderate to late preterm birth, low birth weight, small for gestational age, large for gestational age, respiratory distress syndrome, transient tachypnea of newborn, tachycardia or bradycardia, haemolytic diseases, other neonatal jaundice, anaemia, syndrome of infant of mother with gestational diabetes, and hypoglycemia in infants born to vaccinated mothers. There was no association between maternal Tdap, infant Apgar score at 5 min after birth, asphyxia, sepsis or infection, or hypoxic ischemic encephalopathy. Infant exposure to Tdap during pregnancy was associated with a higher mean birthweight (not clinically significant) and higher odds for ankyloglossia and neonatal erythema toxicum diagnoses. There were insufficient observations to allow examination of the effect of Tdap on extreme preterm and very preterm birth, and stillbirth, infant death, or microcephaly. Overall, we found no outcomes of concern associated with the administration of Tdap during pregnancy. NZ Health and Disability Ethics Committee Approval #14/N.T.A/169/AM05.

Evaluating WHO-Recommended Interventions for Preterm Birth: A Mathematical Model of the Potential Reduction of Preterm Mortality in Sub-Saharan Africa

BACKGROUND

Preterm birth, a leading cause of neonatal mortality, has the highest burden in low-income countries. In 2015, the World Health Organization (WHO) published recommendations for interventions to improve preterm outcomes. Our analysis uses the Maternal and Neonatal Directed Assessment of Technology (MANDATE) model to evaluate the potential effects that WHO-recommended interventions could have had on preterm mortality in sub-Saharan Africa in 2015.

METHODS

We modeled preterm birth subconditions causing mortality (respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, sepsis, birth asphyxia, and low birth weight). For each subcondition, models were populated with estimates of WHO-recommended intervention prevalence, case fatality, coverage, and efficacy. Various scenarios modeled improved coverage of single and combined interventions compared with baseline.

RESULTS

In 2015, approximately 500,000 neonatal deaths due to preterm birth occurred in sub-Saharan Africa. Single interventions with the greatest impact on preterm mortality included oxygen/continuous positive airway pressure (44,000 lives saved), cord care (38,500 lives saved), and breastfeeding (30,200 lives saved). Combined with improved diagnosis/transfer to a hospital, the impact of interventions showed greater reductions in mortality (oxygen/continuous positive airway pressure, 134,100 lives saved; antibiotics, 28,600 lives saved). Combined interventions had the greatest impact. Together, hospital delivery with comprehensive care for respiratory distress syndrome saved 190,600 lives, and comprehensive thermal care, breastfeeding, and prevention/treatment for sepsis saved 94,400 lives.

CONCLUSION

In 2015, WHO-recommended interventions could have saved the lives of nearly 300,000 infants born preterm in sub-Saharan Africa. Combined interventions are necessary to maximize impact. Mathematical models such as MANDATE can estimate effects on health outcomes to allow health officials to prioritize implementation strategies.

Estimation of Gestational Age via Image Analysis of Anterior Lens Capsule Vascularity in Preterm Infants: A Pilot Study

Introduction: Anterior lens capsule vascularity (ALCV) is resorbed in the developing fetus from 27 to 35 weeks gestation. In this pilot study, we evaluated the feasibility and validity of combining smartphone ophthalmoscope videos of ALCV and image analysis for gestational age estimation. Methods: ALCV videos were captured longitudinally in preterm neonates from delivery using a PanOptic® Ophthalmoscope with an iExaminer® adapter (Welch-Allyn). ALCV video frames were manually selected and quantified using semi-automatic image analysis. A predictive model based on ALCV features was compared to gold-standard ultrasound gestational age estimates. Results: A total of 64 image-capture sessions were carried out in 24 neonates. Ultrasound-estimated gestational age and ALCV-predicted gestational age estimates indicate that the two methods are similar (r = 0.78, p < 0.0001). ALCV estimates of gestational age were within 0.11 ± 1.3 weeks of ultrasound estimates. In the final model, gestational age was predicted within ± 1 week for 54% and within ± 2 weeks for 86% of the measures. Conclusions: This novel application of smartphone ophthalmoscopy and ALCV image analysis may provide a safe, accurate and non-invasive technology to estimate postnatal gestational age, especially in low income countries where gestational age may not be known at birth.

Open-source, machine and deep learning-based automated algorithm for gestational age estimation through smartphone lens imaging

Gestational age estimation at time of birth is critical for determining the degree of prematurity of the infant and for administering appropriate postnatal treatment. We present a fully automated algorithm for estimating gestational age of premature infants through smartphone lens imaging of the anterior lens capsule vasculature (ALCV). Our algorithm uses a fully convolutional network and blind image quality analyzers to segment usable anterior capsule regions. Then, it extracts ALCV features using a residual neural network architecture and trains on these features using a support vector machine-based classifier. The classification algorithm is validated using leave-one-out cross-validation on videos captured from 124 neonates. The algorithm is expected to be an influential tool for remote and point-of-care gestational age estimation of premature neonates in low-income countries. To this end, we have made the software open source.

Pertussis Immunisation in Pregnancy Safety (PIPS) Study: A retrospective cohort study of safety outcomes in pregnant women vaccinated with Tdap vaccine

BACKGROUND

New Zealand has funded the administration of tetanus, diphtheria and acellular pertussis (Tdap) vaccine during pregnancy to prevent infant pertussis since 2013. The aim of this study was to assess the safety of Tdap vaccine administered to pregnant women as part of a national maternal immunisation programme.

METHODS

We conducted a national retrospective observational study using linked administrative New Zealand datasets. The study population consisted of pregnant women eligible to receive funded Tdap vaccination from 28 to 38 weeks gestation in 2013. Primary study outcomes were based on prioritised adverse events for the assessment of vaccine safety in pregnant women, as defined by WHO and Brighton Collaboration taskforces. We examined the effect of Tdap vaccination on prioritised maternal outcomes using Cox proportional hazard models. Adjusted hazard ratios controlled for key confounding variables.

RESULTS

In the cohort of 68,550 women eligible to receive funded antenatal Tdap vaccination during 2013, 8178 (11.9%) were vaccinated and 60,372 (88.1%) were unvaccinated. The use of Tdap in pregnancy was not associated with an increase in the rate of primary outcomes, including preterm labour; pre-eclampsia; pre-eclampsia with severe features; eclampsia; gestational hypertension; fetal growth restriction; or post-partum haemorrhage. Tdap also did not increase secondary outcomes, including gestational diabetes mellitus; antenatal bleeding; placental abruption; premature rupture of membranes; preterm delivery; fetal distress; chorioamnionitis; or, maternal fever during or after labour. Lactation disorders was the only secondary maternal outcome with a significantly increased hazard ratio. Tdap vaccine had a protective effect on pre-eclampsia with severe features, preterm labour, preterm delivery, and antenatal bleeding.

CONCLUSION

We did not detect any biologically plausible adverse maternal outcomes following Tdap vaccination during pregnancy. This study provides further assurance that Tdap administration during pregnancy is not associated with unexpected safety risks.

Clinical interventions to reduce stillbirths in sub-Saharan Africa: a mathematical model to estimate the potential reduction of stillbirths associated with specific obstetric conditions

OBJECTIVE

Stillbirths are among the most common adverse pregnancy outcomes, with 98% occurring in low-income countries. More than one-third occur in sub-Saharan Africa (SSA). However, the medical conditions causing stillbirths and interventions to reduce stillbirths from these conditions are not well documented. We estimated the reductions in stillbirths possible with combinations of interventions.

DESIGN

We developed a computerised model to estimate the impact of various interventions on stillbirths caused by the most common conditions. The model considered the location of obstetric care (home, clinic or hospital) and each intervention's efficacy, penetration and utilisation. Maternal transfers were also considered.

SETTING AND POPULATION

Pregnancies in SSA in 2012.

METHODS

For each condition, we created a series of scenarios involving different combinations of interventions and modelled their impact on stillbirth rates.

MAIN OUTCOME MEASURES

Stillbirths associated with various maternal and fetal conditions and the percentage reduction with various interventions.

RESULTS

Eight to ten maternal and fetal conditions were responsible for most stillbirths, but none for more than 15%. The most common conditions causing stillbirths in SSA include obstructed labour and uterine rupture, fetal distress and umbilical cord complications, fetal growth restriction, pre-eclampsia/eclampsia, and placental abruption/placenta praevia. Syphilis and malaria contribute smaller numbers. Reducing stillbirths requires appropriate diagnosis and management of each condition, usually including hospital care for monitoring and delivery, often by caesarean section. Maternal syphilis and malaria were the only conditions for which outpatient management alone reduced stillbirth.

CONCLUSIONS

Most stillbirths in low-income countries occur at term and during labour and therefore are preventable by appropriate obstetric care. Management focused on the maternal and fetal conditions that cause stillbirths is necessary to achieve stillbirth rates approaching those found in high-income countries.

TWEETABLE ABSTRACT

Reducing stillbirth incidence requires appropriate management of each causative condition and often caesarean delivery.

Interventions to reduce neonatal mortality: a mathematical model to evaluate impact of interventions in sub-Saharan Africa

AIM

To determine which interventions would have the greatest impact on reducing neonatal mortality in sub-Saharan Africa in 2012.

METHODS

We used MANDATE, a mathematical model, to evaluate scenarios for the impact of available interventions on neonatal deaths from primary causes, including: (i) for birth asphyxia - obstetric care preventing intrapartum asphyxia, newborn resuscitation and treatment of asphyxiated infants; (ii) for preterm birth - corticosteroids, oxygen, continuous positive air pressure and surfactant; and, (iii) for serious newborn infection - clean delivery, chlorhexidine cord care and antibiotics.

RESULTS

Reductions in infection-related mortality have occurred. Between 80 and 90% of deaths currently occurring from infections and asphyxia can be averted from available interventions, as can 58% of mortality from preterm birth. More than 200 000 neonatal deaths can each be averted from asphyxia, preterm birth and infections. Using available interventions, more than 80% of the neonatal deaths occurring today could be prevented in sub-Saharan Africa.

CONCLUSION

Reducing neonatal deaths from asphyxia require improvements in infrastructure and obstetric care to manage maternal conditions such as obstructed labour and preeclampsia. Reducing deaths from preterm birth would also necessitate improved infrastructure and training for preterm infant care. Reducing infection-related mortality requires less infrastructure and lower-level providers.

Maternal Mortality from Obstructed Labor: A MANDATE Analysis of the Ability of Technology to Save Lives in Sub-Saharan Africa

Objective The aim of the study is to evaluate clinical interventions to significantly reduce maternal mortality from prolonged labor, obstructed labor, and prolonged obstructed labor (PL/OL/POL) in sub-Saharan Africa (SSA). Methods A mathematical model-Maternal and Neonatal Directed Assessment of Technology ("MANDATE")-was created for SSA with estimated prevalence for PL/OL/POL and case fatality rates from hemorrhage, infection, and uterine rupture. Based on a literature review and expert opinion, the model was populated with estimated likelihoods of the current healthcare system ability to diagnose, transfer, and treat women with these conditions. Impact on maternal mortality of improved diagnosis, transfer, and delivery to relieve PL/OL/POL was assessed. Results Without current technologies, the model estimated 8,464 maternal deaths annually in SSA from these conditions. Imputing current diagnosis, transfer, and treatment of PL/OL/POL, an estimated 7,033 maternal deaths occur annually from these complications. With improved PL/OL/POL diagnosis and improved transfer, 1,700 and 740 lives could be saved, respectively. Improved diagnosis, transfer, and treatment for PL/OL/POL reduce the mortality rate to 864 maternal deaths annually, saving 6,169 lives. If improved transfusion and antibiotic use were added, only 507 women per year would die from PL/OL/POL in SSA. Conclusion In SSA, increasing diagnostics, transfer to higher care, and operative delivery could substantially reduce maternal mortality from PL/OL/POL. Synopsis A computerized model of obstructed labor in SSA was created to explore the interventions necessary to reduce maternal mortality from this condition.

Diagnosis of placental malaria in poorly fixed and processed placental tissue

Background

Placental histopathology has been considered the gold standard for diagnosis of malaria during pregnancy. However, in under-resourced areas placental tissue is often improperly fixed and processed; the resulting formalin pigment is difficult to distinguish from malaria pigment. This study examines two alternative diagnostic methods: polymerase chain reaction (PCR) and a novel immunohistochemistry (IHC)-based method using an antibody against histidine-rich protein 2 (HRP2).

Methods

Placental histopathology from 151 pregnant women in Kinshasa was assessed by two blinded microscopists and compared with peripheral blood PCR and IHC for HRP2. The Cohen’s kappa coefficients were calculated to assess the test agreement. The sensitivity and specificity of individual tests were calculated using PCR or IHC as the reference standard as well as latent class analysis (LCA).

Results

PCR and IHC correlated fairly well. The correlation between the two blinded microscopists was poor, as there was widespread formalin pigment. Using LCA, all of the tests had high specificities. The most sensitive test was IHC (67.7 %), with PCR as second-best (56.1 %).

Conclusions

PCR and/or IHC are suitable diagnostics when the presence of formalin pigment substantially compromises placental histopathology.

Resuscitation and Obstetrical Care to Reduce Intrapartum-Related Neonatal Deaths: A MANDATE Study

To evaluate the impact of neonatal resuscitation and basic obstetric care on intrapartum-related neonatal mortality in low and middle-income countries, using the mathematical model, Maternal and Neonatal Directed Assessment of Technology (MANDATE). Using MANDATE, we evaluated the impact of interventions for intrapartum-related events causing birth asphyxia (basic neonatal resuscitation, advanced neonatal care, increasing facility birth, and emergency obstetric care) when implemented in home, clinic, and hospital settings of sub-Saharan African and India for 2008. Total intrapartum-related neonatal mortality (IRNM) was acute neonatal deaths from intrapartum-related events plus late neonatal deaths from ongoing intrapartum-related injury. Introducing basic neonatal resuscitation in all settings had a large impact on decreasing IRNM. Increasing facility births and scaling up emergency obstetric care in clinics and hospitals also had a large impact on decreasing IRNM. Increasing prevalence and utilization of advanced neonatal care in hospital settings had limited impact on IRNM. The greatest improvement in IRNM was seen with widespread advanced neonatal care and basic neonatal resuscitation, scaled-up emergency obstetric care in clinics and hospitals, and increased facility deliveries, resulting in an estimated decrease in IRNM to 2.0 per 1,000 live births in India and 2.5 per 1,000 live births in sub-Saharan Africa. With more deliveries occurring in clinics and hospitals, the scale-up of obstetric care can have a greater effect than if modeled individually. Use of MANDATE enables health leaders to direct resources towards interventions that could prevent intrapartum-related deaths. A lack of widespread implementation of basic neonatal resuscitation, increased facility births, and emergency obstetric care are missed opportunities to save newborn lives.

Tranexamic acid to reduce postpartum hemorrhage: A MANDATE systematic review and analyses of impact on maternal mortality

OBJECTIVE

Postpartum hemorrhage (PPH) is a major cause of maternal mortality, with almost 300,000 cases and ~72,000 PPH deaths annually in sub-Saharan Africa. Novel prevention methods practical in community settings are required. Tranexamic acid, a drug to reduce bleeding during surgical cases including postpartum bleeding, is potentially suitable for community settings. Thus, we sought to determine the impact of tranexamic acid on PPH-related maternal mortality in sub-Saharan Africa.

STUDY DESIGN

We created a mathematical model to determine the impact of interventions on PPH-related maternal mortality. The model was populated with baseline birth rates and mortality estimates based on a review of current interventions for PPH in sub-Saharan Africa. Based on a systematic review of literature on tranexamic acid, we assumed 30% efficacy of tranexamic acid to reduce PPH; the model assessed prophylactic and treatment tranexamic acid use, for deliveries at homes, clinics, and hospitals.

RESULTS

With tranexamic acid only in the hospitals, less than 2% of the PPH mortality would be reduced. However, if tranexamic acid were available in the home and clinic settings for PPH prophylaxis and treatment, a nearly 30% reduction (nearly 22,000 deaths per year) in PPH mortality is possible.

CONCLUSION

These analyses point to the importance of preventive and treatment interventions compatible with home and clinic use, especially for sub-Saharan Africa, where the majority of births occur at home or community health clinics. Given its feasibility to be given in the home, tranexamic acid has potential to save many lives.

The MANDATE model for evaluating interventions to reduce postpartum hemorrhage

OBJECTIVE

To create a comprehensive model of the comparative impact of various interventions on maternal, fetal, and neonatal (MFN) mortality.

METHODS

The major conditions and sub-conditions contributing to MFN mortality in low-resource areas were identified, and the prevalence and case fatality rates documented. Available interventions were mapped to these conditions, and intervention coverage and efficacy were identified. Finally, a computer model developed by the Maternal and Neonatal Directed Assessment of Technology (MANDATE) initiative estimated the potential of current and new interventions to reduce mortality.

RESULTS

For PPH, the sub-causes, prevalence, and MFN case fatality rates were calculated. Available interventions were mapped to these sub-causes. Most available interventions did not prevent or treat the overall condition of PPH, but rather sub-conditions associated with hemorrhage and thus prevented only a fraction of the associated deaths.

CONCLUSION

The majority of current interventions address sub-conditions that cause death, rather than the overall condition; thus, the potential number of lives saved is likely to be overestimated. Additionally, the location at which mother and infant receive care affects intervention effectiveness and, therefore, the potential to save lives. A comprehensive view of MFN conditions is needed to understand the impact of any potential intervention.

Plasmodium falciparum parasitaemia in the first half of pregnancy, uterine and umbilical artery blood flow, and foetal growth: a longitudinal Doppler ultrasound study

BACKGROUND

During early pregnancy, the placenta develops to meet the metabolic demands of the foetus. The objective of this analysis was to examine the effect of malaria parasitaemia prior to 20 weeks' gestation on subsequent changes in uterine and umbilical artery blood flow and intrauterine growth restriction.

METHODS

Data were analysed from 548 antenatal visits after 20 weeks' gestation of 128 women, which included foetal biometric measures and interrogation of uterine and umbilical artery blood flow. Linear mixed effect models estimated the effect of early pregnancy malaria parasitaemia on uterine and umbilical artery resistance indices. Log-binomial models with generalized estimating equations estimated the effect of early pregnancy malaria parasitaemia on the risk of intrauterine growth restriction.

RESULTS

There were differential effects of early pregnancy malaria parasitaemia on uterine artery resistance by nutritional status, with decreased uterine artery resistance among nourished women with early pregnancy malaria and increased uterine artery resistance among undernourished women with early pregnancy malaria. Among primigravidae, early pregnancy malaria parasitaemia decreased umbilical artery resistance in the late third trimester, likely reflecting adaptive villous angiogenesis. In fully adjusted models, primigravidae with early pregnancy malaria parasitaemia had 3.6 times the risk of subsequent intrauterine growth restriction (95% CI: 2.1, 6.2) compared to the referent group of multigravidae with no early pregnancy malaria parasitaemia.

CONCLUSIONS

Early pregnancy malaria parasitaemia affects uterine and umbilical artery blood flow, possibly due to alterations in placentation and angiogenesis, respectively. Among primigravidae, early pregnancy malaria parasitaemia increases the risk of intrauterine growth restriction. The findings support the initiation of malaria parasitaemia prevention and control efforts earlier in pregnancy.

Biotinylation of histones in human cells. Effects of cell proliferation

An enzymatic mechanism has been proposed by which biotinidase may catalyze biotinylation of histones. Here, human cells were found to covalently bind biotin to histones H1, H2A, H2B, H3, and H4. Cells respond to proliferation with increased biotinylation of histones; biotinylation increases early in the cell cycle and remains increased during the cycle. Notwithstanding the catalytic role of biotinidase in biotinylation of histones, mRNA encoding biotinidase and biotinidase activity did not parallel the increased biotinylation of histones in proliferating cells. Biotinylation of histones might be regulated by enzymes other than biotinidase or by the rate of histone debiotinylation.

Sensory nerve evoked responses in spinal cord injury

Previous studies have documented the presence of fibrillations, positive waves, and decreased motor evoked response amplitudes in spinal cord injury (SCI) subjects. The purpose of this study was to further evaluate sensory nerve status in this population. Twenty-eight subjects with SCI for at least five months and evidence of spasticity were included. Sural sensory and tibial motor evoked response amplitudes were measured. The mean sural sensory amplitude was 8.0 +/- 5.9 microV (normal = 15.0 +/- 5.3 microV). The mean tibial motor amplitude was 5.1 +/- 4.3 mV (normal = 11.7 +/- 3.8 mV). In six subjects with significantly reduced sural sensory amplitudes, more extensive electrodiagnostic testing was performed. These studies showed diffusely decreased lower extremity sensory and motor evoked response amplitudes and diffuse positive waves and fibrillations in no particular distribution. Thus, subjects with SCI may have sensory as well as motor nerve abnormalities. An intact connection between the second order and primary sensory neuron may be necessary for maintenance of axonal integrity of the primary neuron.

Internal vessel occlusion: an improved technique for small vessel anastomosis

During infragenicular bypass, internal occlusion of the distal vessel avoids unnecessary dissection and potentially damaging use of external clamps or vessel loops while improving exposure and patency. This technique is especially useful in patients with small or calcific vessels in whom distal reconstruction is necessary for limb salvage.

Subcutaneous endometriosis diagnosed by fine needle aspiration cytology

The fine needle aspiration cytology (FNAC) of two patients manifesting cutaneous/subcutaneous endometriosis is presented. Endometrial tissue sampled by the aspiration technique manifested different cytologic characteristics as compared to those of endometrial tissue obtained by standard exfoliative methods. A primary difference was the appearance of the endometrial cells in syncytial clusters in the aspirate, in contrast to the three-dimensional clusters seen in exfoliated material. These cases emphasize the need to include endometriosis in the differential diagnosis of palpable lesions of the abdominal wall, especially in women with healed surgical scars, and the role of FNAC in diagnosing such lesions.

Studies of phosphorus metabolism by isolated nuclei. XII. Some fundamental properties of the incorporation of 32Pi into polyphosphate by rat liver nuclei

Rat liver nuclei incubated in vitro catalyze a sustained incorporation of 32Pi into polyphosphate. A preliminary estimate indicates a minimal rate of 10 moles of Pi incorporation into polyphosphates/h/mg protein. Polyphosphate is the predominant acid-insoluble product of nuclear phosphorylation; its formation is dependent on the presence of a divalent cation and is catalyzed by a system or systems as yet uncharacterized.

Pheochromocytoma in pregnancy: diagnosis and collaborative management

Antenatal diagnosis and appropriate management of pheochromocytoma complicating pregnancy offers a reduction in mortality for both mother and fetus. We have presented the successful management of such a case, emphasizing the close collaboration between obstetricians, pediatricians, anesthesiologists, surgeons, and internists that is mandatory for a successful outcome.

Evaluating alcoholism and drug abuse knowledge in medical education: a collaborative project

A series of six modular examinations, each representing a substance abuse problem, were developed by a National Institute on Drug Abuse task force working with consultants from the National Board of Medical Examiners (NBME). Each examination contained a patient management problem and multiple-choice questions. The examinations were administered to 629 third- and fourth-year U.S. medical students, and the results indicated that students performed less well in this area than on the traditional content of the NBME examinations. Students performed better on items related to pharmacologic effects of drugs of abuse, Alcoholics Anonymous, and the treatment of delirium tremens. Students did less well on items related to metabolic and biochemical areas; emergency room treatment of drug-overdosed, comatose patients; and legal issues in substance abuse. As a result of these data, a syllabus explaining each item in the available modules was developed, score-reporting to participating schools was modified, and the modules were shortened. Implications for medical education in substance abuse are discussed.

The calcar femorale redefined

The calcar femorale is a spur of thickened bone that lies deep to the lesser trochanter but posterior to the neutral axis of the femoral neck. The calcar is thickest medially where it joins the compression buttress of the neck and gradually thins as it passes laterally. X-ray films taken at right angles to the neutral axis of the femoral neck best portray the calcar femorale, which stands out like a solid bone spur as if viewing along the line of a picket fence. The presence of the calcar femorale affects the configuration of peritrochanteric fractures. It should not be confused with the primary medial compression buttress of the femoral neck.

Tissue distribution of primaquine in the rat

The distribution of primaquine was measured in seven rat tissues at 15-180 min after the intraperitoneal injection of the antimalarial 8-aminoquinoline. The half-life of unmetabolized primaquine was 4.0 h in lung, 1.7-1.9 h in blood, spleen, kidney and heart, and 1.2 h in liver. At each interval, the concentrations of unmetabolized primaquine were (in order): lung greater than liver, kidney, spleen greater than heart greater than brain greater than or equal to blood. At 3 h after the injection of [6-O-methyl-3H]primaquine, unmetabolized primaquine constituted 10% of the total 3H in blood and 40-60% of the total 3H in liver, brain, heart and kidney.

Traumatic posterior fracture-dislocation of the lumbosacral joint

An unusual case of traumatic posterior fracture-dislocation of the lumbosacral joint is presented. Spontaneous fusion occurred without attempted reduction. Osteomyelitis and paraplegia were associated with the injury.

Rumination in a 7-year-old child

Regurgitation of food by rumination has rarely been reported in latency-age children. A 7-year-old boy had symptoms of rumination, gagging, bruxism, and enuresis. During the oppositional stage of development many unresolved conflicts had developed between the patient and his parents. Short-term psychotherapy which focused on resolution of the power struggles produced rapid remission of the symptoms. A two-year follow-up showed no recurrence of difficulty.

Obsidian Sources Characterized by Neutron-Activation Analysis

Concentrations of elements such as manganese, scandium, lanthanum, rubidium, samarium, barium, and zirconium in obsidian samples from different flows show ranges of 1000 percent or more, whereas the variation in element content in obsidian samples from a single flow appears to be less than 40 percent. Neutron-activation analysis of these elements, as well as of sodium and iron, provides a means of identifying the geologic source of an archeological artifact of obsidian.

Eastern North American Archaeology: A Summary

The initial occupation of Eastern North America was by small bands of people who gained their livelihood by hunting and gathering. As time passed, the occupants of different regions be came increasingly familiar with the available natural resources. The de velopment or introduction of new tools and devices enabled the people to ex ploit their environments more effective ly, until, by Late Archaic times, popu lation size had increased, in terms both of density within a given area and num ber of people in individual social units. The initial agricultural productivity aided the culmination of the long cul tural traditions in the remarkable pro ductions and practices of the Hope wellian complexes of Middle Woodland times. The major Hopewellian centers reflect the marked change in societal organization and patterns. The costumes of the dead and the manner of their burial clearly reflect individual status differentiations, while artistic creativity is probably to be equated with incipient specialization of labor. Many of the Mississippian societies reached an even more advanced plateau of cultural de velopment, with fortified towns, an or ganized priesthood, dominant hereditary chiefs, political and military alliances, and a well-developed class system. The details of the cultural develop ment in Eastern North America are unique, but the general trend may be regarded as a common one in human society, and the patterns of behavior, as analogous to those developed by other peoples in other areas of the Old World and the New.