An in vitro toxicological assessment of two electronic cigarettes: E-liquid to aerosolisation

Interest in the toxicological assessment of iterations of e-cigarette devices, e-liquid formulations and flavour use is increasing. Here, we describe a multiple test matrix and in vitro approach to assess the biological impact of differing e-cigarette activation mechanism (button vs. puff-activated) and heating technology (cotton vs. ceramic wick). The e-liquids selected for each device contained the same nicotine concentration and flavourings. We tested both e-liquid and aqueous extract of e-liquid aerosol using a high throughput cytotoxicity and genotoxicity screen. We also conducted whole aerosol assessment both in a reconstituted human airway lung tissue (MucilAir) with associated endpoint assessment (cytotoxicity, TEER, cilia beat frequency and active area) and an Ames whole aerosol assay with up to 900 consecutive undiluted puffs. Following this testing it is shown that the biological impact of these devices is similar, taking into consideration the limitations and capturing efficiencies of the different testing matrices. We have contextualised these responses against previous published reference cigarette data to establish the comparative reduction in response consistent with reduced risk potential of the e-cigarette products tested in this study as compared to conventional cigarettes.

A contextualised e-cigarette testing strategy shows flavourings do not impact lung toxicity in vitro

Vaping has the potential to reduce the individual health risks associated with smoking and e-cigarette flavours have been reported to help smokers' transition from cigarettes. In this manuscript, we provide evidence to support the reduced risk potential of e-cigarette aerosols and flavours by assessing commercially available e-liquids (Vuse ePod - Manufactured by British American Tobacco) in a 2D in vitro screening approach. We also analysed selected flavours using a more physiologically relevant 3D (MucilAir) whole aerosol exposure model, measuring toxicity and functional endpoints such as Trans Epithelial Electrical Resistance, Cilia Beat Frequency and Active Area. To contextualise responses, we have compared e-cigarette aerosol to cigarette smoke (1R6F research cigarette) and calculated the percentage reduction using a point of departure approach. We show that aerosolised flavoured e-liquids, (appropriately stewarded) do not increase the overall measured aerosol toxicity when compared to cigarette smoke. In fact, we demonstrate that the measured in vitro cellular toxicity of flavoured e-cigarette products remains >95% reduced when compared to cigarette smoke toxicity, using point of departure (IC₈₀) approach. These data indicate that the overall product toxicity is not increased in a flavour dependent manner and that flavoured e-cigarette products can potentially play a role in tobacco harm reduction.

A 3D in vitro comparison of two undiluted e-cigarette aerosol generating systems

In vitro studies play an important role in supporting the toxicological assessment of e-cigarettes, with many current methods reliant on sophisticated in vitro exposure systems designed for conventional cigarette testing. In this study, we have compared two distinct systems; the modified Vitrocell VC10 and Borgwaldt LM4E designed to deliver undiluted e-cigarette aerosol. We assessed the cytotoxicity response of 3D reconstituted lung tissue (MucilAir) exposed to undiluted aerosol from ePen3 (closed modular e-cigarette) using these two exposure systems. As the induced cytotoxicity profiles were comparable, we then compared these responses against historical eBox (open modular e-cigarette) and 3R4F reference cigarette data to show evolution of product technology. This latter approach was deemed possible by monitoring intrinsic donor-to-donor control variability over a three-year period, bridging between exposure systems and observed biological responses. Despite the differences in the technology, on a puff-by-puff basis these machines gave remarkably similar cytotoxicity profiles for ePen3, as determined by MTT, and consistency of pre-cytotoxicity markers: transepithelial electrical resistance (TEER), cilia beat frequency and cilia active area. When responses are compared as a function of exposed nicotine concentration, we see differences due to the dynamics of the exposure systems. The parity of responses between the systems in generated undiluted aerosol has allowed us to compare back to previously published eBox data, irrespective of aerosol generating system and MucilAir donor, showing how evolution from open systems to podmod e-cigarette design can make a step change in the cytotoxicity profile of the product.

Effectiveness of workplace wellness programmes for dietary habits, overweight, and cardiometabolic health: a systematic review and meta-analysis

Background

The workplace offers a unique opportunity for effective health promotion. We aimed to comprehensively study the effectiveness of multicomponent worksite wellness programmes for improving diet and cardiometabolic risk factors.

Methods

We did a systematic literature review and meta-analysis, following PRISMA guidelines. We searched PubMed-MEDLINE, Embase, the Cochrane Library, Web of Science, and Education Resources Information Center, from Jan 1, 1990, to June 30, 2020, for studies with controlled evaluation designs that assessed multicomponent workplace wellness programmes. Investigators independently appraised the evidence and extracted the data. Outcomes were dietary factors, anthropometric measures, and cardiometabolic risk factors. Pooled effects were calculated by inverse-variance random-effects meta-analysis. Potential sources of heterogeneity and study biases were evaluated.

Findings

From 10 169 abstracts reviewed, 121 studies (82 [68%] randomised controlled trials and 39 [32%] quasi-experimental interventions) met the eligibility criteria. Most studies were done in North America (57 [47%]), and Europe, Australia, or New Zealand (36 [30%]). The median number of participants was 413·0 (IQR 124·0–904·0), and median duration of intervention was 9·0 months (4·5–18·0). Workplace wellness programmes improved fruit and vegetable consumption (0·27 servings per day [95% CI 0·16 to 0·37]), fruit consumption (0·20 servings per day [0·11 to 0·28]), body-mass index (−0·22 kg/m² [−0·28 to −0·17]), waist circumference (−1·47 cm [−1·96 to −0·98]), systolic blood pressure (−2·03 mm Hg [−3·16 to −0·89]), and LDL cholesterol (−5·18 mg/dL [−7·83 to −2·53]), and to a lesser extent improved total fat intake (−1·18% of daily energy intake [−1·78 to −0·58]), saturated fat intake (−0·70% of daily energy [−1·22 to −0·18]), bodyweight (−0·92 kg [−1·11 to −0·72]), diastolic blood pressure (−1·11 mm Hg [−1·78 to −0·44]), fasting blood glucose (−1·81 mg/dL [−3·33 to −0·28]), HDL cholesterol (1·11 mg/dL [0·48 to 1·74]), and triglycerides (−5·38 mg/dL [−9·18 to −1·59]). No significant benefits were observed for intake of vegetables (0·03 servings per day [95% CI −0·04 to 0·10]), fibre (0·26 g per day [−0·15 to 0·67]), polyunsaturated fat (−0·23% of daily energy [−0·59 to 0·13]), or for body fat (−0·80% [−1·80 to 0·21]), waist-to-hip ratio (−0·00 ratio [−0·01 to 0·00]), or lean mass (1·01 kg [−0·82 to 2·83]). Heterogeneity values ranged from 46·9% to 91·5%. Between-study differences in outcomes were not significantly explained by study design, location, population, or similar factors in heterogeneity analyses.

Interpretation

Workplace wellness programmes are associated with improvements in specific dietary, anthropometric, and cardiometabolic risk indicators. The heterogeneity identified in study designs and results should be considered when using these programmes as strategies to improve cardiometabolic health.

A screening approach for the evaluation of tobacco-free 'modern oral' nicotine products using Real Time Cell Analysis

In many regulated industries there is an increasing pressure to provide timely and robust risk assessment data to support product launches. Real-time cell analysis (RTCA) is a tool that allows for the fast and relatively labour-free cytotoxic assessment of test compounds, compared to traditional methods. Here, we propose an application for the RTCA platform to provide a screening approach, to evaluate the cytotoxic potential of tobacco-free nicotine pouches, also termed modern oral product (MOP), to determine the contribution of differing nicotine strengths (4-11 mg) and a range of available flavour types from multiple markets, on overall product toxicity. Aqueous extracts were prepared for all products using 1 pouch in 20 mL cell culture media and applied to the cell system for 24 h. Test extract nicotine concentrations reflected the increases in product nicotine strength; however, these changes were not present in the same magnitude in the cytotoxicity data obtained from both primary human gingival fibroblasts (HGF) and an NCI-H292 human bronchial epithelial continuous cell line. Furthermore, across the range of flavours and product nicotine strengths tested, H292 cells whilst not the target organ for oral product use, accurately predicted the results seen in HGFs and could be considered a useful surrogate for fast screening studies. H292 cells are more easily cultured and for longer periods, offering a more compatible test system. In conclusion, the data demonstrate the utility of the RTCA platform for the quick assessment of a large range of product variants. Furthermore, for a cytotoxicity measure with this test product, the simple H292 cell line can predict outcomes in the more complex HGF and provide useful pre-clinical cytotoxicity screening data to inform the risk assessment of MOPs and the relative contribution of flavourings, nicotine and other components.

Adipose-only sentinel lymph nodes: a finding during the adaptation of a sentinel lymph node mapping algorithm with indocyanine green in women with endometrial cancer

Objective

To identify factors that affect successful adaptation of sentinel lymph node mapping and those that lead to unintended adipose-only sentinel lymph node identification.

Methods

Surgical and pathological data were prospectively collected on patients with endometrial cancer who underwent sentinel lymph node mapping with indocyanine green with or without pelvic and/or para-aortic lymph node dissection between November 2013 and April 2017. All mapping cases were performed with the robotic system. Adipose-only specimens were defined as a sentinel lymph node without a pathologically identified lymph node after ultrastaging.

Results

A total of 202 patients were included: 83% had endometrioid pathology, 12% serous, 3% carcinosarcoma, and 2% clear cell, with mixed pathology noted in 2%. The bilateral sentinel lymph node detection rate was 66%, and the rate of mapping at least a unilateral sentinel lymph node was 86%. Neither the bilateral nor the unilateral sentinel lymph node mapping rate changed with increased surgeon experience. The rate of adipose-only sentinel lymph node identification was more frequent when comparing the first 10 cases (37%), cases 11 – 30 (28%), and > 30 cases (9%) (P = 0.006). Body mass index > 30 kg/m2, uterine fibroids, The International Federation of Gynecology and Obstetrics (FIGO) grade, and histology were not found to have a statistically significant impact on either sentinel lymph node identification or adipose-only sentinel lymph node identification. Adipose-only sentinel lymph nodes were more likely with increased time from cervical injection to identification of the sentinel lymph node in the right hemipelvis. The median range was 28 min (14–73) for true sentinel lymph node identification vs 33 min (23–74) for adipose-only sentinel lymph node identification (P = 0.02).

Conclusion

Patient and surgeon factors did not impact the identification of sentinel lymph nodes over time. Adipose-only sentinel lymph nodes were more frequently identified in the initial cases and represent a potential complication to adapting sentinel lymph node biopsy without lymphadenectomy. The increase in adipose-only sentinel lymph node identification that was associated with time from cervical injection may represent delayed or disrupted uptake of indocyanine green.

Seven factors predict a delayed diagnosis of cardiac amyloidosis

INTRODUCTION

Diagnostic delay of cardiac amyloidosis (CAm) continues to challenge clinicians. We investigated features associated with delay and ascertained if a diagnostic delay had negative implications for the patient.

METHODS

We performed a retrospective chart review identifying 82 subjects with biopsy-proven and mass-spectrometry-identified CAm with clinical and epidemiologic data including first potential symptom of amyloidosis. Pathology slides were scored for extent of amyloid. Robust statistical analyses including generalized linear and ordered logistic regression analysis were performed.

RESULTS

There was a 22 month (median) delay in diagnosis, more pronounced (34 months) in subjects with transthyretin (ATTR) amyloidosis. Seven factors predict a delayed diagnosis including ATTR amyloid type (ratio =2.17, 95% CI 1.31-3.59), having carpal tunnel syndrome (2.13, CI 1.49-3.03) and age <70 at first symptom (1.85, CI 1.30-2.61). Individuals with delays of 1+ years had higher levels of NT proBNP (4451 vs. 2559 pg/mL, p = .016) and longer PR intervals (225 vs. 162 ms, p < .001) at the time of diagnosis.

CONCLUSIONS

Diagnostic delays negatively affect cardiac function. Of the predictive clinical features, carpal tunnel syndrome was frequent and its presence should lead to a more aggressive analysis for CAm in the appropriate clinical settings.

Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT & process evaluation of contingency management

There are approximately 256,000 heroin and other opiate users in England of whom 155,000 are in treatment for heroin (or opiate) addiction. The majority of people in treatment receive opiate substitution treatment (OST) (methadone and buprenorphine). However, OST suffers from high attrition and persistent heroin use even whilst in treatment. Contingency management (CM) is a psychological intervention based on the principles of operant conditioning. It is delivered as an adjunct to existing evidence based treatments to amplify patient benefit and involves the systematic application of positive reinforcement (financial or material incentives) to promote behaviours consistent with treatment goals. With an international evidence base for CM, NICE recommended that CM be implemented in UK drug treatment settings alongside OST to target attendance and the reduction of illicit drug use. While there was a growing evidence base for CM, there had been no examination of its delivery in UK NHS addiction services. The PRAISe trial evaluates the feasibility, acceptability, clinical and cost effectiveness of CM in UK addiction services. It is a cluster randomised controlled effectiveness trial of CM (praise and financial incentives) targeted at either abstinence from opiates or attendance at treatment sessions versus no CM among individuals receiving OST. The trial includes an economic evaluation which explores the relative costs and cost effectiveness of the two CM intervention strategies compared to TAU and an embedded process evaluation to identify contextual factors and causal mechanisms associated with variations in outcome. This study will inform UK drug treatment policy and practice. Trial registration ISRCTN 01591254.

African born women living with HIV in the United States: unmet needs and opportunities for intervention

Africa born (immigrant) women comprise a disproportionate number of Black women living with HIV in the United States. Though they are at risk for mental health disorders, including psychological distress and depression, little is known about their experience with these important predictors of quality of life, retention in care and adherence to antiretroviral therapy. In this qualitative study, we used constructivist grounded theory to explore the psychosocial and mental health challenges of African born women living with HIV in Boston and New York City. We conducted one-on-one semi-structured interviews with 45 women. Major themes contributing to psychological distress and depressive symptoms included (1) pre-immigration HIV-related stigma; (2) persistent HIV-related stigma post-immigration, (3) undocumented immigration status, (4) economic insecurity, and (5) intimate partner violence (IPV). Many participants described ongoing depressive symptoms or histories of depressive episodes. Yet, most had not been formally diagnosed or treated for depression. Prayer, consultation with faith leadership, and support groups were described most frequently as useful interventions. Future research should explore these thematic areas among a larger, more representative sample of African born women living with HIV to determine differences by country of origin across thematic areas. These data would be useful to inform development of innovative and culturally appropriate interventions.

Validity of a condition specific outcome measure for fragile X syndrome: the Aberrant Behaviour Checklist-utility index

BACKGROUND

The purpose of this study was to assess the construct validity of the Aberrant Behaviour Checklist-utility index (ABC-UI) by examining the relationship between healthcare resource utilisation by patients with fragile X syndrome (FXS) as well as burden experienced by their caregivers.

METHOD

In 2011, a total of 350 US caregivers of individuals with FXS completed a questionnaire that captured information on FXS-related burden as well as the ABC-Community. Using the ABC-UI, a condition-specific outcome measure derived from the ABC-Community, five utility index categories were created: very low (0.00-0.33); low (0.34-0.66); moderate (0.67-0.77); high (0.78-0.89); and very high (0.90-1.00). Multivariable regression models examined the association between the utility value and nine burden-related outcomes.

RESULTS

Approximately 2% of individuals with FXS were in the very low utility index category, 31% low, 27% moderate, 38% high and 3% very high. The median utility value was 0.74. Women with FXS and adults 18 years and older had higher values. Regression results indicate that individuals with higher utility values were more likely to have fewer specialist visits, use fewer prescription medications, need fewer hours of unpaid caregiving, inflict fewer caregiver injuries and have caregivers with fewer mental health provider visits.

CONCLUSIONS

The ABC-UI appears to function well as condition-specific outcome measure, and as an indicator of health-related quality-of-life and economic burden in individuals with FXS. Among patients with FXS in the US and their caregivers, significant differences in health care resource utilisation and burden exist across health state utility categories.

Aggression in fragile X syndrome

BACKGROUND

Individuals with fragile X syndrome (FXS), especially men, have long been described as presenting with significant behavioural challenges. Despite this known aspect of the phenotype, there has been little research exploring the prevalence, frequency, nature or consequences of aggressive behaviour in FXS.

METHODS

This study used survey methodology to gather caregiver reports on the types, frequency and severity of aggressive behaviour in 774 individuals with FXS.

RESULTS

Based on caregiver report, nearly all (>90%) male and female individuals were reported to have engaged in some aggression over the previous 12 months, with a third of male cases and slightly fewer than 20% of female cases being described as engaging in moderate to severe aggression or being diagnosed or treated for aggression. Further, aggressive behaviours in male individuals were serious enough that 30% had caused injuries to caregivers and 22% had caused injuries to peers or friends. Sensory issues and hyperactivity were significant predictors of the frequency of aggressive acts, while sensory issues and anxiety were predictive of the severity of aggression. Traditional behaviour management techniques as well as medication was described as the most common and successful treatment options.

CONCLUSIONS

Aggressive behaviours are a significant concern for a subsample of both male and female individuals with FXS. Given that sensory concerns were predictive of both the frequency and the severity of aggression suggests these behaviours may be a reactive means of escaping uncomfortable situations.

Detection of Foot-and-mouth Disease Virus RNA and Capsid Protein in Lymphoid Tissues of Convalescent Pigs Does Not Indicate Existence of a Carrier State

A systematic study was performed to investigate the potential of pigs to establish and maintain persistent foot-and-mouth disease virus (FMDV) infection. Infectious virus could not be recovered from sera, oral, nasal or oropharyngeal fluids obtained after resolution of clinical infection with any of five FMDV strains within serotypes A, O and Asia-1. Furthermore, there was no isolation of live virus from tissue samples harvested at 28-100 days post-infection from convalescent pigs recovered from clinical or subclinical FMD. Despite lack of detection of infectious FMDV, there was a high prevalence of FMDV RNA detection in lymph nodes draining lesion sites harvested at 35 days post-infection, with the most frequent detection recorded in popliteal lymph nodes (positive detection in 88% of samples obtained from non-vaccinated pigs). Likewise, at 35 dpi, FMDV capsid antigen was localized within follicles of draining lymph nodes, but without concurrent detection of FMDV non-structural protein. There was a marked decline in the detection of FMDV RNA and antigen in tissue samples by 60 dpi, and no antigen or viral RNA could be detected in samples obtained at 100 dpi. The data presented herein provide the most extensive investigation of FMDV persistence in pigs. The overall conclusion is that domestic pigs are unlikely to be competent long-term carriers of infectious FMDV; however, transient persistence of FMDV protein and RNA in lymphoid tissues is common following clinical or subclinical infection.

Cigarette smoke condensate affects monocyte interaction with endothelium

OBJECTIVE

Circulating monocytes adhere to the endothelium and migrate into the intima contributing to atherosclerotic plaque growth. Cigarette smoke is a risk factor for atherosclerosis, but it is not completely known how it affects monocyte behavior in atherogenesis.

METHODS

We studied the effects of cigarette smoke condensate (CSC) on human monocytes (HM) chemotaxis and transmigration through an endothelial cell (EC) monolayer.

RESULTS

Pre-treatment with CSC caused a decrease in HM chemotaxis and transmigration (-55% and -18% vs control, p < 0.05, respectively), paralleled by a reduced expression of Rac 1 GTPase. On the contrary, direct exposure of both HM and EC to CSC increased (+23% vs control, p < 0.05) HM transmigration, paralleled by a strong stimulation of VCAM1 and ICAM1 expression by ECs, and by a slight increase in monocyte integrin expression. An enhancement of monocyte transmigration was obtained after the exposure of both HM and EC to medium conditioned by HM previously incubated with CSC (+265% vs control, p < 0.001). CSC showed a stimulatory effect on the expression by HM of TLR4, MCP1, IL8, IL1beta, and TNFalfa, which was ablated by pre treatment with PDTC. Incubation with neutralizing antibodies against both MCP1 or IL8 completely abolished the CSC-conditioned medium induced HM transmigration.

CONCLUSIONS

CSC induces HM to release chemotactic factor(s), which amplify the recruitment and transmigration of inflammatory cells through EC, but CSC may also reduce HM migratory capacity. Therefore, exposure to CSC affects monocyte behavior and interaction with the endothelium, thus potentially facilitating and/or further aggravating the atherogenic process.

Therapy service use among individuals with fragile X syndrome: findings from a US parent survey

BACKGROUND

Fragile X syndrome (FXS) is known to be associated with a range of developmental challenges, yet the occurrence and intensity of therapy services along with associated factors have not been determined.

METHOD

In a US national survey, caregivers provided information regarding the therapy services received by their sons (n = 1013) and daughters (n = 283) with FXS (from birth to 63 years; mean = 15.6 years, SD = 10.6). Caregivers reported (1) type, (2) amount, (3) location, and (4) overall satisfaction with services. Associations with other child variables and family income were also examined.

RESULTS

Key findings included that 72% of males and 47% of females were currently receiving at least one type of therapy service; the most common services for both males and females were speech-language therapy (ST) and occupational therapy (OT). Overall, males were more likely to receive therapy services as well as a greater number of services than females. Autism status was significantly associated with both males and females receiving ST and males receiving OT and behaviour management therapy. Therapies were provided in a variety of locations, and parents were generally satisfied with the amount and quality of therapy services. Age-related declines were evident in the use of services for both males and females, with very few individuals receiving any therapy services after 20 years of age.

CONCLUSIONS

This study provides a baseline description of the current state of therapy services for children with FXS, laying a foundation for future research and recommendations for service provision and policy.

Automated erythrocytapheresis in the treatment of severe falciparum malaria

Removal of parasitized erythrocytes is generally considered to be of value as adjunctive therapy in severe falciparum malaria with high parasitaemia. This is commonly achieved by exchange transfusion. We describe three cases of severe falciparum malaria treated by automated erythrocytapheresis (red cell exchange) in addition to quinine and conventional supportive therapy. Erythrocytapheresis consists of removal of the red-cell fraction by apheresis. Plasma, leukocyte and platelet fractions are returned to the patient. In all cases, dramatic reduction in parasitaemia was achieved within 2 h with subsequent complete clinical recovery. Erythrocytapheresis has significant advantages over exchange transfusion in terms of speed, efficiency, haemodynamic stability and retention of plasma components such as clotting factors and may thus represent an improvement in adjunctive therapy for severe malaria.

Automated red cell exchange in sickle cell disease

Red cell exchange is important in the care of acutely ill sickle-cell patients, and may be life-saving. An automated red cell exchange technique has been developed using a Baxter blood cell separator, enabling an isovolaemic exchange to be performed within 2.5 h. A total of 20 procedures have been performed in 15 patients, including one woman in the third trimester of pregnancy, with a mean decrease of 72% in the circulating sickle haemoglobin (HbS) level. This method enables almost all adult patients with sickle cell anaemia to have their HbS reduced to safe levels by only one procedure. The procedure was well tolerated by all patients, including those who were acutely ill. This technique provides an effective procedure for reducing the percentage of circulating HbS rapidly in acutely ill patients with complications of sickle cell anaemia.

Adaptation of latex-enhanced assay for percent glycohemoglobin to a Dade Dimension analyzer

At present no method for glycohemoglobin (%HbA1c) is automated on a main-line analyzer to allow joint measurement with other indicators of diabetic control such as glucose and cholesterol. We describe an adaptation of a latex-enhanced competitive immunoassay for quantifying %HbA1c to the Dade International Dimension analyzer. After a manual hemolysis step, HbA1c and total hemoglobin (Hb) are determined separately. The concentration of glycated beta-subunit is obtained from the immunoassay, whereas Hb is assessed colorimetrically from a derivatized form. Both reactions were fully optimized for accuracy, precision, and specificity on the Dimension; stabilities of reagents and calibration were established; and potential interferences were assessed. The analyzer gave reliable results over the required clinical range of 1-15% HbA1c. Within-run and total assay variation were within 5% of the target CV limits, as determined by ANOVA with three representative sample pools across 20 days. Close agreement with an established HPLC procedure and a commercially available enzyme immunoassay was observed for 140 samples from clinically defined patient groups. Additional samples from patients with hemoglobinopathies (n = 20) demonstrated a more complex relationship between methods. We conclude that adaptation of the method for use with the Dimension analyzer is a valid method for quantifying %HbA1c.

N-methyl-2-pyrrolidone as a cosolvent: relationship of cosolvent effect with solute polarity and the presence of proton-donating groups on model drug compounds

N-Methyl-2-pyrrolidone (methylpyrrolidone), a cosolvent which has been used in veterinary medicine and in transdermal delivery devices, was investigated as a cosolvent for model drug compounds of widely varying polarity. These compounds were digoxin, sulfamethoxazole, hydrocortisone acetate, theophylline, phenytoin, and reserpine. Methylpyrrolidone was found to be an extremely efficient cosolvent for low solubility polar drugs such as digoxin or drugs containing multiple proton-donating groups such as phenytoin. The increase in solubility observed in aqueous solutions of digoxin and phenytoin to which 0.2 volume fraction of methylpyrrolidone was added was 500x and 65x, respectively. Significant deviations from log-linear solubilization were observed with digoxin, sulfamethoxazole, phenytoin, and reserpine, indicating significant water-solute-cosolvent interactions.

Mechanistic study and kinetic determination of vitamin C

A simple specific method for the determination of vitamin C has been investigated by elucidating the reaction mechanism of its oxidation with cerium(IV) in sulphuric acid media. The reaction kinetics and rate measurements which form the basis of this method were determined by following the decrease of the intense yellow colour of cerium(IV) at 405 nm. The fixed-time and fixed-concentration methods were investigated. The former was found to be more precise and was consequently used for the determination. Advantages of this method over the B.P. and other methods are discussed.

Prospective study of perinatal transmission of Chlamydia trachomatis

During a five-year period, 262 (4.7%) of 5,531 pregnant women had positive cervical cultures for Chlamydia trachomatis, and 131 of their infants were followed up prospectively to ascertain the outcome of chlamydial exposure during the birth process. Culture-confirmed inclusion conjunctivitis of the newborn was seen in 23 (18%) of the infants. Chlamydial pneumonia was diagnosed in 21 (16%) of the infants at risk. Chlamydia trachomatis was recovered from 47 of the infants (36%), while 79 (60%) showed serologic evidence of infection. Subclinical rectal and vaginal infections were detected in 14% of infants at risk. In our population, 2.8% of newborn infants show serologic evidence of perinatal chlamydial infection and 1.4% develop either chlamydial pneumonia or conjunctivitis. Incidence rates of this magnitude indicate the need for programs aimed at preventing perinatal transmission of C trachomatis.

Experience with the routine use of erythromycin for chlamydial infections in pregnancy

In an effort to prevent perinatal acquisition of Chlamydia trachomatis, we offered treatment with erythromycin ethylsuccinate (400 mg four times a day for seven days, given at 36 weeks' gestation) to 184 pregnant women with cervical chlamydial infections. Thirty-two women refused treatment; 24 of their infants were followed and served as the controls. Therapy was discontinued by 5 of 10 women who had gastrointestinal disturbances. Forty-seven women who completed therapy refused infant follow-up; in four (9 percent) of these women, therapy had failed to eradicate the infection. Sixty women and 59 infants completed the entire protocol; 55 (92 percent) of the women had negative cultures for chlamydia at follow-up. Chlamydial infection developed in 4 (7 percent) of the 59 infants of treated mothers, as compared with 12 (50 percent) of the 24 infants of untreated mothers; this difference was significant (P less than 0.001). With a success rate of 92 percent (98 of 107 patients) in treating maternal infection and with a relatively low intolerance rate (3 percent; 5 of 152), this regimen appears to be an effective, although not ideal, therapy for chlamydial infection in pregnant women. We conclude that in settings in which the prevalence of chlamydia infection is high, a routine program of screening pregnant women for cervical C. trachomatis, followed by treatment of those infected, would be cost effective and would reduce infant morbidity.